Volume Vol 1 Issue # 2

Transformation from Growth to Aging in Human Astrocytes Cell Cultures: The Role of NADH-Glutamate Dehydrgenase Isoenzyme.

Remigius N. Okea†, Godson O. Osuji‡
Date Received November 7. 2024
Date Accepted December 2. 2024

Abstract

Human astrocyte cultures have primarily been observed up to the confluence stage, a pivotal moment when cellular proliferation equates to programmed cell death, thus stabilizing cell populations. Traditionally, research has largely overlooked the subsequent attrition (aging) stage when cell dynamics undergo substantial transformations. This study illuminated this critical phase by contrasting human astrocyte cell culture characteristics at confluency (day 9) and, at post-confluency (day 11). At day 9, when control A cells were harvested, the total human astrocyte cell count increased to an impressive 8.71 million cells from initial 0.375 million cells. In stark contrast, at day 11 (2 days after confluency), when control B (aging cells) were harvested, the total human astrocyte cells had markedly declined to 6.79 million cells despite keeping the culture conditions identical. This represented a cell attrition rate of 0.96 million cells per day with a calculated human astrocyte mean lifetime of 9.07 days (218 hours), indicating a shift to survival metabolism, meaning a shift in aging cell molecular-chemistry. Whereas cell count was rapidly declining at this aging stage, cell viability, ironically, improved tremendously from 97.9% to 99.3%; an indication that the more viable the cells are the more likely they survive. These findings underscored marked variations in cell characteristics, including population density, cellular dimensions, morphological profiles, growth kinetics, attrition rates, and biochemical metabolism between human astrocytes in these two states. Utilizing a comprehensive analysis of Glutamate dehydrogenase (GDH) isoenzyme pattern fingerprint, results unveiled profound differences in metabolic processes between the confluency group (control A), with 13 isoenzymes, and cells culled at two days post-confluency (control B), with 18 isoenzymes. The data conclusively illustrated that as astrocytes transition from confluency to attrition (aging), they undergo a major metabolic shift that is correlated to NADH-GDH hexameric isoenzyme activity. This study expands the understanding of astrocytic molecular biology and physiology by highlighting the importance of the post-confluency stage, suggesting that cellular aging, characteristics and functionality is driven by molecular changes in NADH-GDH hexameric isoenzyme complex that endows cells the capacity to respond to their internal and external environment irrespective of genes. These results conjures a tectonic shift on approaches to disease diagnosis and treatment, potentially offering new ways to diagnose and cure Alzheimer’s disease, ALS, sickle cell, cancer, diabetes, drug addiction and aging.

 

Corresponding author email: admin@aapcr.org American Academy of Primary Care research (AAPCR), San Antonio, Texas.

American Academy of Primary Care research (AAPCR), San Antonio, Texas. (Formerly at Prairie View A&M University, Prairie View, Texas).

1.0 INTRODUCTION

The study of human astrocyte cell lines is a vital part of the exploration of the human brain [1, 2, 3], spanning the fields of neurobiology, neuroscience, and medicine. These glial cells, vital for neural support, synaptic connection, and homeostasis, undergo a significant metamorphosis as they age, transitioning from growth to maturity [4, 5, 6, 7, 8].

Astrocytes—once deemed mere bystanders in the complex neural tapestry—now unveil themselves as dynamic players in brain function [9]. Their evolution from youthful precursors to post-confluent aging cells encapsulates a cycle that is intrinsically linked to not just the health of the brain but also its decline [4, 5, 6, 7, 8.]. The transition from vitality to senescence is a nuanced narrative, rich with biochemical interactions and molecular cues that orchestrate cellular behavior over time [1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11.]. Yet, the precise timing, nature, and mechanisms governing this transformation have long marveled research scientists, eluding a clear understanding.

To crack this cerebral code, research embarked on an innovative journey with cultured human astrocyte cell lines. By nurturing precursor astrocyte cells to confluence, this research created an environment conducive to maturation—a critical stage where the cells fully express their potential and functionalities. Two days later, like clockwork, transformation began to unfold as the astrocytes entered a post-confluency state reminiscent of aging process [4, 5, 6, 7.]. This pivotal shift heralds a cascade of changes: alterations in morphology, redefinitions of cell signaling pathways, and a reshaping of interactions with neighboring neuronal counterparts [4, 5, 6.].

Harnessing advanced imaging techniques and biochemical assays, [1, 12] research meticulously observed this transformation, mapping the cellular landscape as it peeled back layers of mystery laden within those elongated processes and altered gene expressions [1, 4, 5, 6, 12]. Each day revealed new discoveries—data points connecting the dots of aging with exacerbations in neurodegenerative conditions, [6, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25] unveiling opportunities to develop therapeutics aimed at preserving these brain cells from the merciless passage of time.

As research delve deeper into the aging dynamics of astrocytes through cultured models, this study inch closer to answering the monumental questions around aging of cells that have captivated scientists for generations. Research is now closer than ever before to unveil the molecular secretes governing the aging and functional decline of astrocyte cells [4, 5, 6, 7, 12.]. The peeling of the exoskeleton of age, could open bare the mechanisms that translates into interventions that could rejuvenate not only astrocytes but the very fabric of the human neural network. Inside the walls of research laboratories, the growth story of astrocytes morphs from one of mere observation to one of strategic exploration—one that holds promise for not only understanding but potentially reversing the age-old mystery, astrocyte cell aging and transformations.

1.1 Astrocytes: Playing a critical role in the central nervous system, astrocytes form a substantial part of the brain and spinal cord's cellular landscape. These star-shaped glial cells not only account for up to 50% of the cellular volume in certain regions [12, 26]  but also revel in their abundance, outnumbering neurons by an impressive five to one [27, 28] in some parts of the brain. Varying in shape and function, astrocytes are more than just structural elements; they are dynamic participants in the intricate symphony of neural signaling, playing vital roles in synaptic transmission [29] and maintaining the delicate balance of the central nervous system (CNS) [1, 2, 3, 4, 5, 6, 7, 12].

Each of the two recognized subtypes—protoplasmic and fibrous astrocytes—contributes to the brain's ecosystem in unique ways. [28, 29] Protoplasmic astrocytes are known for their extensive processes that engage closely with neurons, influencing synapse formation and modulation. Fibrous astrocytes, on the other hand, can primarily be found in the white matter, responsible for supporting myelinated axons and ensuring efficient signal transmission [6, 12, 28, 29, 30.].

Beyond their structural support and involvement in synaptic function, astrocytes also regulate blood flow to the CNS, acting as key orchestrators in neurovascular coupling. They respond to neuronal activity, ensuring that energy demands are met not just through direct provision of nutrients, but also through complex signaling interactions that are still being unraveled [29, 30, 31.].

In health and disease alike, astrocytes are at the forefront. They tirelessly secrete a myriad of substances, functioning as reactive agents during injuries and actively participating in the brain’s recovery processes [1, 4, 5, 6, 12, 13.]. Their role expands further when considering neurological diseases, as alterations in astrocytic function have been implicated in various disorders, making them a focal point of research for understanding brain pathologies [28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40.].

However, many mysteries still shroud their full range of functions and the substances they produce. As the scientific community continues to peel back the layers of these remarkable cells, we stand on the brink of discoveries that could redefine our approach to treating neurological diseases, with astrocytes revealed not just as support cells, but as essential players in the complex narrative of brain health and disease. Understanding these intricate dualities will be crucial for paving paths toward innovative therapeutic strategies in the realm of neurology.

1.2 Astrocyte Biology and Pathology: Astrocytes, the remarkable star-shaped glial cells of the central nervous system (CNS), form an intricate tapestry seamlessly woven throughout the neural landscape. These cells are not mere passive bystanders; rather, they play a pivotal role in maintaining homeostasis and providing critical support to neurons. However, when the CNS is confronted with various insults—be it trauma, injury, or disease—astrocytes spring into action in a phenomenon known as reactive astrogliosis [28, 41.]. This adaptive response, while essential for repair, has emerged as a hallmark of CNS pathology, indicating a deeper entanglement of astrocytes in both health and disease.

Recent advancements in neuroscience are shedding light on this intricate process. Research scientists are unraveling the complex functions and mechanisms behind reactive astrogliosis, revealing that it is far from simplistic. It is a graded continuum that hinges not only on the nature of the insult but also on contextual signals that dictate the astrocytic response. No longer considered merely a pathological remnant, reactive astrocytes showcase a versatile molecular arsenal that equips them to either restore homeostasis or contribute to system failures within the CNS [28, 29, 30, 41, 42.].

Through innovative transgenic mouse models, scientists are meticulously dissecting individual features of astrogliosis and the enigmatic process of glial scar formation. This model-driven exploration is illuminating the intricate roles astrocytes play in specific clinical and pathological contexts, reshaping our understanding of their functional dynamics. Rather than a static or uniform response, the range of changes orchestrated by reactive astrogliosis can transition from reversible adaptations, such as upregulating protective gene expressions and modest cellular hypertrophy while preserving tissue architecture, to enduring transformations that involve permanent scarring and the reorganization of tissue structures [28, 29, 30, 41, 42.].

Recent research has illuminated critical insights into the intricate process of astrocyte maturation within the cerebral cortex, as often observed in studies involving mice and rodent models. While these findings are tailored to specific species, they shed light on the universal principles governing astrocyte development across mammals [43]. During this esoteric journey of differentiation, various neuroligins—specifically neuroligin 1 (NL1), neuroligin 2 (NL2), and neuroligin 3 (NL3)—have been implicated in orchestrating both astrocyte morphogenesis and synaptogenesis. These proteins serve as vital components, facilitating the connection between astrocytes and neurons, thereby influencing the architecture and functionality of the synaptic landscape [44, 45, 46.].

Compelling evidence is emerging, emphasizing the dual nature of reactive astrogliosis—it can both thwart and exacerbate CNS disorders. The balance between the loss of essential astrocyte functions and the gain of pathological attributes is a delicate balance underlying many neurological conditions. Research scientists now face the pivotal challenge of fully deciphering this complex interplay within the context of various CNS disorders, paving the way for targeted therapies that could manipulate astrocyte responses for therapeutic gain. The journey to understanding astrocytes, their protective roles, and their detrimental consequences continues to unfold, revealing a world of intricate cellular interactions at the heart of the CNS.

Moreover, the understanding of astrogliogenesis extends further when considering the dynamic modifications that astrocytes undergo in response to injury and inflammation. Recent studies have documented a multitude of morphological transformations accompanied by molecular shifts, intricately linked to these external stimuli. Central to this process are an array of transcription factors and signaling proteins, which collectively drive the adaptive responses of astrocytes, enabling them to rearrange their cellular structures and functions in accordance with the demands of their microenvironment [43, 44, 45, 46.].

Thus, the exploration of astrocyte maturation highlights not only the transformative potential of these glial cells but also underscores the relevance of molecular interactions in mediating their roles during critical periods of neural activity and pathophysiological states. With ongoing advances in our understanding of astrocytic function, future endeavors may unlock new therapeutic avenues through which to harness these versatile cells in the face of neurological injury and disease.

To date, however, a concrete mechanism elucidating the transition of astrocytes from a confluency to a post-confluency state during growth remains elusive. While extensive studies in mice and rodent models have provided invaluable insights, they inevitably hit a wall when it comes to direct relevance to humans. Evolution has finely tuned human astrocytes, placing them light years ahead of murine species in complexity and functional capacity.

The complex interplay of molecular factors in astrocyte morphogenesis highlights the intricate narrative unfolding at the cellular level. Key players such as glial fibrillary acidic protein (GFAP), Zinc finger and BTB domain-containing 20 (ZBTB20), Sox9, and NFIA intricately orchestrate the transformation of astrocytes, these pivotal support cells in the central nervous system. Each of these proteins contributes in unique ways, some acting through the repression of the mouse brain-2 (Brn-2) gene to facilitate this metamorphosis [46].

Because of this, research scientists are met with the challenge of reconciling these findings from animal models with the more sophisticated human system. Understanding the precise pathway of astrocyte morphogenesis in humans is paramount as it could hold the key to unlocking therapies for a range of neurological disorders. As science vigorously paves the way through these mysteries, the intricate labyrinth of astrocyte development remains a tantalizing frontier waiting to be explored further.

1.3 Human Astrocytes differs from Rat and Rodent Astrocytes: The landscape of experimental neurology has long relied on the cellular models derived from rats and other rodents [33, 34, 35, 36, 37, 47.].This foundational approach has led to significant insights into neuronal and glial functions. However, as advanced research methods and a deeper understanding of evolution surface, the stark differences between these models and human biology come to light. The human lineage diverged substantially from rodents and primates, ushering in unique brain functionalities that cannot be adequately reflected through these earlier model organisms.

Emerging studies illuminate the intricate architecture of human astrocytes. These glial cells, crucial for maintaining homeostasis and supporting neuronal function, are notably larger in size and more complex than those of rats and rodents [39, 40.]. Research led by Oberheim NA, et al (2006) [39, 40] emphasized that human astrocytes not only surpass rodents in size but also exhibit a remarkable polarization of Glial Fibrillary Acidic Protein (GFAP+) [11]. This unique feature allows for processes and intercellular communications that may extend exponentially, up to tenfold in capacity compared to their non-human counterparts. [38, 39, 47]

Such findings point to a pressing need for scientists to reassess the reliance on traditional animal models for research into human neural diseases and pathogenesis. While rodent studies have afforded profound insights, the gap in evolutionary biology makes extrapolations of such findings riddle with huge errors [38, 39, 40.]. In light of this mounting evidence, it becomes increasingly essential that future research embraces cellular models that are identical in complexity to human astrocytes. As research continues to peel back the layers of human neurobiology, this study stands on the brink of more precise and relevant medical breakthroughs that honor the uniqueness of human astrocytes.

1.4 GDH Responsible for Cell Metabolic Reprograming: In the intricate world of cellular biology, the ability of cells to regenerate and adapt is not just fascinating, it is essential for understanding various physiological processes and the underlying mechanisms of aging. Among the molecular juggernauts that play a pivotal role in cellular reprogramming, NADH-dependent glutamate dehydrogenase (GDH) stands out [48]. This hexameric enzyme complex emerges as the ultimate gatekeeper of cellular function, deftly regulating biomolecular and physical changes within cells, particularly impacting astrocyte growth and maturation as highlighted by Godson Osuji and Okea (2024) [48].

Research has taken a closer look at the remarkable evolution of GDH isoenzymes within human astrocyte cells as they transition from state to state, namely from mature entities to those increasingly marked by the signatures of aging. By isolating and characterizing the distinct alterations in these NADH-GDH isoenzymes, and illustrating the nuanced interplay between enzymatic activity and cellular morphology—a narrative of congruency revealing how changes in biochemical pathways mirror observable shifts in cell structure can become visible, even to the naked eye, after western blot [48, 49, 50, 51, 52, 53.].

Examining human astrocyte cells (HACs) provides a robust platform for understanding these processes, allowing results to resonate with real-life implications. As research further delves into the variations of GDH hexameric isoenzyme patterns, it seeks to elucidate how these transitions underpin the physical metamorphosis of astrocytes. By recognizing the relationship between GDH enzyme dynamics and astrocyte morphology, research aims to pave the way for novel insights into cellular aging mechanisms—potentially unlocking new avenues for therapeutic interventions in neurological conditions. This exploration is more than a simple observation; it showcases the intricate relationship between molecular regulation and cellular identity, illuminating the paths that lead from youthful vitality to the complexities of aged cellular landscapes.

Using astrocyte cells as the subject, and the hexameric isoenzymes of NADH-GDH as the pivot enzyme, a comparison-based research approach hereunder provided evidence that transitioning astrocyte cells from growth, at confluency, to aging cells, at post confluency, correlated to the transitioning of  NADH-GDH isoenzymes from a simple binomial to a highly complex distribution pattern that could unveil novel technologies for not only in pharmacological diagnoses and prevention but also potentially lead to novel drugs and therapies that can cure most inexplicable neurological disorders and most primary clinical infirmities.

 

2.0 MATERIALS AND METHODS

2.1 American Academy of Primary Care (AAPCR) Phase 1 Astrocyte Project: A Groundbreaking Study on Human Astrocyte Cell Culture

Human astrocyte progenitor lines were acquired from iXcell Biotech, and their protocols were used by Southwest Research Institute (SwRI) to grow the cultures [54, 55].The experimental phase extended up to 11 days, with conscientious monitoring of cellular developments during this crucial period. Notably cultures were in duplicates, creating Control A and Control B, both seeded with identical cell numbers from the same astrocyte progenitor cells (Fig. 1)

Control A was meticulously harvested at day 9, precisely at the point of confluency. On the other hand, Control B was harvested at day 11, 2 days post-confluency.

Fig. 1. Diagram Showing the Experimental Design for Cell Culture Comparison                                     

 

CONTROL A DAY 1

 

CONTROL B DAY 1
 

 

CONTROL A DAY 2

 

CONTROL B DAY 2
 

 

CONTROL A DAY 3

 

CONTROL B DAY 3

                  

 

CONTROL A DAY 4

 

CONTROL B DAY 4
 

 

CONTROL A DAY 5

 

CONTROL B DAY 5
 

 

CONTROL A DAY 6

 

CONTROL B DAY 6
 

 

CONTROL A DAY 7

 

CONTROL B DAY 7
 

 

CONTROL A DAY 8

 

CONTROL B DAY 8
 

 

CONTROL A DAY 9

 

CONTROL B DAY 9
 

 

 

 

CONTROL B DAY 10
 
  CONTROL B DAY 11

 

Legend to Figure 1: Diagram showing experimental design for cell culture comparison. Astrocyte cell cultures were performed in T-75 flasks under identical environmental conditions for control A and control B. Control A and control B were both cultured to day 9 at which time control A was harvested. Control B continued receiving same experimental condition until day 11 when it was harvested. The experimental design here shows how these 2 sets of controls are compared on a day to day basis until day 9, and how it enabled to compare control A (day 9) and control B (day 11). This design also created internal controls for the experiment such that on a day to day T-75 flasks culture contents served as cross-controls for both control A and control B. Using this method experimental errors and wide variabilities seen by observation, images and markers can be spotted during experimentation and corrected. No such errors were encountered in this experiment due to meticulous adherence to culture protocols. 

 

2.2 Human Astrocyte Cell (HAC) Culture Protocol:

Culture protocols from the American Type Culture Collection (ATCC) [56, 57, 58.], were utilized. Upon receipt of the frozen human astrocytes (HA) cells, they were allowed to acclimate in vapor phase of liquid nitrogen for a period of 24 hours. [20, 21].

Media Preparation: Astrocyte Medium was prepared according to the following protocol provided by iXcell1 . Fetal Bovine Serum (FBS), Growth Supplement, and Antibiotic-Antimycotic (Anti-Anti) were thawed in a 37°C water bath. To ensure complete mixing of the contents, the tubes were gently tilted multiple times before adding them to the medium. The remainder of the process was carried out under aseptic conditions in a Biological Safety Cabinet (BSC). The 50mL of FBS, 1mL of Growth Supplement, and 5mL of Antibiotic-Antimycotic were added to the 500mL iXCell HA medium in the BSC and thoroughly mixed. The final concentrations of components in Media are 10% FBS, 0.2% Astrocyte Supplement, and 1% Anti-Anti. The Astrocyte Medium was then aliquoted into 50mL conical tubes, with each tube containing 30mL of the medium. The reconstituted medium remains stable for one month when stored at 4°C, with minimal exposure to light.

2.3 Thawing and Seeding of HACs: Thawing of frozen HA cells was performed following the described protocol [56, 57, 58.]. The cells were thawed by placing the vial in a 37°C water bath with gentle agitation for approximately 1 minute, ensuring the cap remained outside the water to minimize contamination risks. Subsequently, the cells were carefully pipetted into a 15mL conical tube containing 5mL of fresh, warm Astrocyte Medium. Centrifugation at 1000 rpm (~220 g) for 5 minutes at room temperature followed, which allowed for the separation of cells from cryopreservation media. The supernatant was then removed, and the cells were re-suspended in 1mL of medium. To assess cell viability and quantity, a 20uL sample of the cell solution was diluted with 180uL of fresh medium and gently agitated to ensure thorough mixing. The diluted sample was analyzed using an NC200 cell counter, and values including cell passage, number of cells, viability, and diameter were recorded. The cells were cultured at a concentration of 5000 cells/cm2 into a T-75 flask, using 10mL of medium volume. It was ensured that the conical tube was thoroughly washed to ensure all cells were successfully seeded. A total of 375,000 cells were seeded per flask to initiate the culture process.

2.4 Daily Media Changes: The process of changing the media for the cultures was performed according to the following protocol. First, media was warmed at 37°C for 20 minutes while ensuring proper mixing. The flasks were removed from the incubator and placed in the biological safety cabinet (BSC), and using a serological pipette, the old media was carefully removed from the flask and collected in labeled containers accordingly, this way preserving the spent media. The labeled spent media were preserved in a freezer (-20°C). At this point, 10 mls of fresh Astrocyte media were pipetted into the flasks, each time, using a new pipet to avoid contamination and to maintain the exact aliquots. This process was repeated over and over until all the media was changed in all the flasks. Astrocyte culture media was changed this way daily.

2.5 Procedure for Harvesting Astrocytes: The harvesting of astrocytes was meticulously executed following a detailed and methodical approach, as outlined in previous studies. [59, 60, 61] The process was divided into two distinct phases, which were critical to understanding cell behavior under varying growth conditions.

In the initial phase, two conditions were established for culturing the cells: Condition A—where cells were allowed to grow to confluency, and Condition B—where cells were permitted to continue growth up to two days past confluency. Control charts presented in Figure 1 served as benchmarks to monitor the growth stages of experimental groups A and B. The cells from both groups were harvested upon reaching their designated growth status.

For Control A: Confluency Harvesting Process is as follows:

  1. The cell medium was carefully aspirated and discarded.
  2. A rapid wash was conducted with 5 mL of sterile phosphate-buffered saline (PBS) to remove residual medium.
  3. Following this wash, 4 mL of Trypsin/EDTA was added to the cells, and incubation at 37°C for 2 minutes facilitated detachment.
  4. Once detached, the enzyme action was neutralized by adding 10 mL of complete cell culture medium.
  5. The cells were gently centrifuged at 220 g for 5 minutes to sediment the cell pellet.
  6. The resultant pellet was re-suspended in 1 mL of fetal bovine serum (FBS)  for further analysis.

A thorough cell count was then performed to assess key parameters, including passage number, total cell count, percentage viability, and diameter of the cells. For long-term storage, the harvested cells were cryopreserved in a solution consisting of 10% dimethyl sulfoxide (DMSO) mixed with culture medium [55, 56, 57].

For Control B: Post-Confluency Harvesting Process was exactly like described for control A above.

The methodologies employed throughout the astrocyte cell culture and harvesting process are in concordance with the recognized standards set forth by institutions like the American Type Culture Collection (ATCC) and numerous esteemed research centers and universities. This rigorous protocol not only ensures reproducibility but also enhances the reliability and efficacy of this research outcomes in the field of cellular neuroscience. [59, 60, 61]

 

2.6 Purification of the NADH-Glutamate dehydrogenase hexameric isoenzymes of human astrocyte cells

2.61 Free Solution Isoelectric Focusing: The Control A human astrocyte cell culture (120,000 cells) harvested on day 9 at cell confluency, and the Control B (120,000 cells) harvested on day 11 at post-confluency were applied for the purification according to the methods of Osuji et al (2021) without any modification. [62 ] Essentially the pellet of the 120,000 cells was homogenized in 80 mL of 15 mM Tris-HCl buffer solution, pH 7.5, containing 20 µL β-mercaptoethanol, 2 Units of DNase 1, and 1 Unit of RNase A for 1 min at maximum speed. The homogenate was left to stand at room temperature for 30 min for DNA and RNA to be degraded. Protein precipitated by solid (NH4)2SO4 between 20% and 55% saturation of the homogenate was collected by centrifugation (10,000 x g, 30 min, 5˚C). The pellet was resuspended in minimum volume of 15 mM Tris-HCl pH 7.5 buffer solution, and dialyzed in 5 L of 15 mM Tris-HCl buffer solution pH 8.5; with three changes of the buffer solution over a period of 36 h.

The dialyzed extract was made up to 50 mL with 10 mM Tris-HCl buffer pH 7.5, and subjected to Rotofor (Bio-Rad, Hercules, CA) isoelectric focusing fractionation. Rotofor fractions were dialyzed in 5 L of 10 mM Tris-HCl buffer solution pH 8.5 also at 5˚C; with three changes of the buffer over a period of 36 h to remove the ampholyte and urea.

2.62 Polyacrylamide Gel Electrophoresis: Aliquots (250 µL) of the dialyzed Rotofor fractions were subjected to Laemmli SDS 12% polyacrylamide gel electrophoresis (PAGE) (100 V, 14 h, 4˚C) to remove other proteins and nucleic acids. Protean II xi electrophoresis cell (Bio-Rad, Hercules, CA) was used. The electrophoresed gels were washed three times with 0.15 mM Tris base at 5˚C to remove the SDS. Gel was thereafter stained with L-glutamate-NAD+-phenazine methosulfate-tetrazolium blue reagent at room temperature. The GDH hexameric redox cycle isoenzyme distribution pattern was photo-documented. Rotofor purification was repeated two or three times to assure reproducibility of the GDH isoenzyme pattern per experimental astrocyte cultured cells. [62, 63, 64]

 

3.0 RESULTS 

3.1 Astrocyte Growth Expectation

Fig. 2. Showing Expected Human Astrocyte Cell Culture Growth Model from iXCells Biotech

 

https://what-when-how.com/wp-content/uploads/2011/05/tmp23265_thumb1.jpg

 

 

Legend to Figure 2: Showing Expected Human Astrocyte Cell Culture Growth Model from iXCells Biotech. The graph show the typical growth expectation of Astrocyte cells as presented in a standard cell culture. Notice the lag phase, the growth phase and the plateau phase; achieving confluency around 8 to 9 days (compare with figure 3).

 

 

3.2 Cell Indices: In the comparative study of astrocyte cell growth, research focused on the development of two separate cell cultures: control A and control B. Both groups started with an equal cell count of 375,000, ensuring a fair baseline for growth assessment. As the culture progressed, the data collected over the course of 11 days revealed significant insights into the proliferation patterns observed in human astrocytes in this experiment.

By the end of day 9, when the harvesting of control A cells were done, the total cell count had surged, exponentially, to an impressive 8.71 million (8,710,000) cells. In stark contrast, by day 11, the analysis of control B cells indicated a significant decay to 6.79 million (6,790,000) cells, a result indicative of a net 1.92 million (1,920,000) cell atoptosis within two days. These results highlight a pivotal shift that occurred shortly after the similarities in growth patterns observed in the first nine days. Fig. 3

Figure 3

 

 

Legend to Figure 3: Astrocyte Cell Growth Curve Comparing Control A and Control B. To assess cell viability and count, a 20uL sample of the cell solution was diluted with 180uL of fresh medium and gently agitated to ensure thorough mixing. The diluted sample was analyzed using an NC200 cell counter, and values including cell passage, number of cells, viability, and diameter were recorded. Direct cell count was performed on days 1 and 9 for control A; and on days 1 and 11 for control B. Using a calculated doubling time (DT) of 1.98 days – see table 4 – the estimated cell numbers for the rest of the days were derived for control A and control B up to day 9 (at confluency). For control B cell count for day 10 was determined using the decay equation – see table 5 – indicating a cell loss of 960,000 cells per day.

 

Table 1

Showing Human Astrocyte Cell Diameter and Culture Days

 

Control

Day 9             Day 11

   

 

 

Cell Diameter

(microns)        

14.8

15.7               15.8

 

               

                      

_______________________________________________

 

 

Legend to Table 1: Cell Diameter Table. To assess cell viability, diameter and count, a 20uL sample of the cell solution was diluted with 180uL of fresh medium and gently agitated to ensure thorough mixing. The diluted sample was analyzed using an NC200 cell counter. This table clearly shows that the cell diameter increases as the cells grow and age. On day 1 diameter was 14.8 microns, then grew to 15.7 micron by day 9, and grew further to 15.8 microns on day 11.

 

 

Table 2

Showing Human Astrocyte Cell Viability and Culture Days

 

Control

Day 9                       Day 11

   

 

 

Cell Viability %        

98.3

97.9                            99.3

 

                 

 

________________________________________________

 

 

Legend to Table 2: To assess cell viability, diameter and count, a 20uL sample of the cell solution was diluted with 180uL of fresh medium and gently agitated to ensure thorough mixing. The diluted sample was analyzed using an NC200 cell counter. This table demonstrates, ironically, that the percent cell viability increases as the culture aged; with a 97.9 % viability at day 9 to a 99.3% viability on day 11. This may represent a process of biochemical selection such that the less biochemically efficient cells undergoing rapid apoptosis in order to conserve total culture biochemical energy; a process pioneered by GDH isoenzymes. This may be liken to what happens in astrogliosis in the human brain.

 

 

Table 3

Showing Estimates of Human Astrocyte Cell Count for Control A and Control B

 

Control A

Control B

Time (Days)

 

 

 

 

 

D0

3.75E+05

3.75E+05

D1

5.32E+05

5.32E+05

D2

7.54E+05

7.54E+05

D3

1.07E+06

1.07E+06

D4

1.52E+06

1.52E+06

D5

2.15E+06

2.15E+06

D6

3.05E+06

3.05E+06

D7

4.33E+06

4.33E+06

D8

6.14E+06

6.14E+06

D9

8.71E+06

8.71E+06

D10

 

7.75E+06

D11

 

6.79E+06

 

 

Legend to Table 3: Control A and control B started with 0.375 million (375,000) cells at the start of the culture. By the end of day 9, when the harvesting of control A cells were done, the total cell count had surged, exponentially, to an impressive 8.71 million (8,710,000) cells. In stark contrast, by day 11, the analysis of control B cells indicated a significant decay to 6.79 million (6,790,000) cells, a result indicative of a net 1.92 million (1,920,000) cell atoptosis within two days. Note that cell counts for the rest of the days were estimated with the calculated doubling time (DT) and the decay constant (see table 4 and 5).

 

 

Table 4.

Table showing Calculation of the Doubling Time (DT) from Study Raw Data using the formula

(DT) = T Ln2 / Ln (N9/N1) *

Control (Day One to Confluency)

 

T (duration)

9

Ln 2

0.693

N1

375000

N9

8710000

N1/N9

23.22667

Ln(N1/N9)

3.145301

T*Ln2

6.237

DT

1.982958

 

 

 

Legend to Table 4: Doubling time (DT) calculation based on the equation DT = T * Ln 2 / Ln (N9/N1). Here T stands for the time duration of the culture to confluence (9 days in this case); Ln 2 represent the natural log of number 2 (which is constant = 0.693). The cell counts on day 1 (N1) and day 9 (N9) are measured from the culture. The calculated DT for Astrocytes in this study was 1.98 days.

 

 

Table 5.

Table showing Calculation of the Mean Lifetime of Human Astrocyte Cells After the cells attained Confluency.

 

Control B

 

Nc

8.71E+06

Nf

6.79E+06

Nf - Nc

-1.92E+06

dt (HR)

48

1/Nc

1.15E-07

1/Nf

1.47E-07

(Nf - Nc) / dt

-4.00E+04

?

-4.59E-03

Mean Lifetime in HR

-2.18E+02

Mean Lifetime in Days

-9.07E+00

 
 
 

 

Legend to Table 5: The mean lifetime (r) is calculation based on the decay equation   
.

Here Nc stands for the number of cells at confluency and Nf (stands for the number of cells at a time after confluency (for control B, it is day 11). Here dN = (Nc – Nf), that is, the change in the cell number from day 9 and day 11; while is the change in time, in this case 9 minus 11 (= -2). The decay constant  is calculated and then used to estimate the mean lifetime (r) of the astrocyte cells (r = 1/. The final calculated mean lifetime (r) of the Astrocytes was 218 hours.

 

Throughout the initial nine days of cultivation, growth dynamics for both control A and control B were notably identical. The graph depicted in Figure 3 illustrates this parallel; both cultures exhibited consistent growth trajectories reflected in identical doubling times of approximately 1.98 days, or 47.52 hours. This uniformity underscores the robustness of the astrocyte cultures prior to the divergence observed in control B. However, by day 11, a salient transformation took place within control B cells. Following a brief period, post-confluence, control B began to undergo morphological changes indicative of maturation, evolving into aging cells. This pivotal metamorphosis marks a significant transition in their lifecycle, contrasting their growth dynamics prior to confluency.

While both sets of astrocyte cells exhibited similar growth rates from the onset of the culture until day 9, ( Fig. 3) the stark differences observed thereafter challenge conventional notions of cell maturity and viability, suggesting that environmental or physiological factors inherent to control B may have prompted this shift. Further exploration into these dynamics will be crucial for advancing our understanding of astrocytic behavior and their implications in neurobiology.

Between day 9 and day 11, astrocytes embarked on a profound transformation, signaling the evolution from their mature state to aging cells. This transition was underscored by a notable decrease in cell population, indicative of extensive cell attrition brought on by net apoptosis—a stark reminder of the relentless march of aging.

Accompanying these changes was a striking shift in cellular morphology: these astrocytes increased in size, reflecting the typical hallmarks of aging as illustrated in Table 1.The once-vibrant niches of these supportive cells appeared more nebulous and scanty, an observation strikingly captured in Figure 4 (day 10 and day 11), which depicted the aging astrocytes as ethereal specters washed in a cloudy haze. This visual transformation offered a poignant glimpse into the senescence process, emphasizing the loss of cellular density and vitality. Observers could almost feel the weight of time in each image, where bustling cellular networks had begun to yield to the silent echoes of decline, manifesting the quintessential characteristics of aging.

Figure 4

Legend to Figure 4: Real-time Phase Contrast Electron Micrographs of the Human Astrocyte Cultures for Control A and Control B on Days 1 to 11 of the Study. The experimental condition for control A and control B were kept identical throughout the study. Each day real-time electron micrograph images of the culture in T-75 flasks were taken for control A (day1 to 9) and for control B (day 1 to 11), and these images are displayed side-by-side here at x 10 magnification on the slides. A total of 375,000 human Astrocyte cells per T-75 flask (representing 5000 cells/cm2 density) were seeded on day 1 for control A and control B. Notice how for control A, the culture appeared consistently denser from visual trends for days 1 through 9. The same is the case for control B, the culture appeared denser from day 1 through 9; but for days 10 and 11 (control B) the image density as visualized appear more scanty and the slides demonstrate some vacuoles (empty spaces). These images also provides the opportunity to compare the trends between control A and control B on a day-by-day basis during the experiment, showing they are identical up to day 9.

 

Together, these changes unveil the intricate saga of astrocyte aging—a story woven with loss, transformation, and the quiet realities of cellular life. The intricate metamorphosis of human astrocytes takes center stage after day 9, when a cascade of biochemical events culminates in a striking revelation: the cells, once teeming with life and vitality, now find themselves on a relentless trajectory towards apoptosis. Through rigorous calculation using the decay equation (as detailed in Table 5), research deciphered the somber narrative written in their lifespans. After reaching confluency, the mean lifetime (MLT) of these invaluable neural support cells stands resilient at 218 hours, equating to a succinct 9.07 days. With a staggering rate of approximately 960,000 cells succumbing each day, the evidence is irrefutable: the vitality of human astrocytes wanes exponentially post-day 9.

This data encapsulates more than just a numerical outcome; it portrays the profound fragility of cellular life. The stark reality emerges that, should the culture continue past day 11 current state, complete apoptosis of the human astrocyte population is poised to unfold within a calculated span of 218 hours. Such dramatic shifts invite further exploration into the underlying mechanisms, potentially allowing for innovative avenues to prolong life or mitigate the effects of cellular senescence in a controlled environment. Thus, the battle against time unfurls before us—a compelling invitation for research scientists to investigate the pathways leading to this inevitable decline.

Throughout the duration of this study, the cells exhibited remarkable  level of viability, as outlined in Table 2. A noteworthy observation emerged on day 11, where the viability of the astrocytes peaked at 99.3%. This was a significant improvement over day 9, which recorded a viability rate of 97.9%, and surpassed the initial measurement on day 1, where the viability was at 98.3%. These findings offer intriguing insights into cellular development. It appears that as astrocytes mature, the process of biomolecular selection, that may not be natural afterall, becomes evident. The less viable, potentially defective cells, seem to be resorbed and eliminated over time, allowing the healthier, more robust cells to thrive. This dynamic process underscores a fascinating paradox: the aging cells, which have navigated through adversities to endure, emerge as more viable over time. In essence, it is as if the surviving cells have undergone a rigorous selection, resulting in a population that is not only resilient but also ideally suited for the demands of their environment. This phenomenon raises thought-provoking questions about the relationship between age, viability, and the natural mechanisms of cellular competition and survival.

Table 1 illustrates the progressive increase in cell diameter as the astrocytes continued to grow and age throughout the study. This relationship between cell size and age has been well-documented in various cell culture investigations. [5, 6, 7] Astrocyte cell diameter increased from 14.8 microns on day one to 15. 7 microns on day nine, and to 15.8 microns on day eleven, a showing of consistent trend towards cell size enlargement. Also notably, the cell diameter for control B on day 11 (15.8 microns), compared to the cell diameter for control A on day 9 (15.7 microns), though subtle yet important and underscores the ongoing biological processes and morphological changes that astrocytes undergo even after reaching confluency, suggesting that their aging is an intrinsic factor that continues to influence their growth and structural properties beyond the immediate cellular density phase. Such findings reinforce the idea that cellular maturation encompasses more than mere proliferation, extending into dynamic alterations of cell morphology that are crucial for understanding astrocyte functionality over time.

3.2 Cell Electron Microscope Images: The investigation of cellular growth patterns with phase-contrast electron microscopy has proven to be an invaluable tool, offering stunning insights into the dynamics of experimental cultures. The images captured (figure 4) revealed strikingly identical growth image patterns for both control A and control B, allowing for insightful side-by-side comparison across culture flasks. This meticulous approach not only strengthened our results but also ensured both internal and external consistency in our findings.

Anomalies observed within these cultures should prompt a thorough internal review of the procedural methodology and the various environmental factors that interactively influence cell proliferation. In this context, any aberration, deviation, or unexpected shift in flask conditions calls for a comprehensive audit to uphold the reliability of the results. No such anormalies were observed during this experiment an indication of meticulous methodology. 

Remarkably, the morphological details established through these observations confirmed that control A and control B exhibited an identical conformation from day 1 until day 9, as illustrated in Figure 4. However, the narrative shifted when we turned the attention to control B on days 10 and 11, precisely two days following confluence. Here, the images presented an astonishing glimpse of transformation, signifying a pivotal moment that could hold keys to understanding growth regulation. (Refer to Fig. 4). This transformation heralds the potential for new hypotheses regarding downstream effects in cellular behavior, opening pathways for further exploration in future studies.

In the snapshots of cellular life captured from early stages of development, vivid imagery reveals the fascinating architecture of astrocytes. As early as day 2, these cells exhibit a remarkable star-like shape, their long, delicate connecting fibers reaching out like the arms of celestial bodies in a cosmic dance. Each branch intertwines to establish networks essential for communication and support, emphasizing the intricate design behind the ordinary yet extraordinary world of neurons.

Fast forward to days 4 and 5, where the narrative takes a vibrant turn – the astrocytes adopt a granule-like appearance. Within these cells, a flurry of activity awakens, hinting at an underlying physiological shift. These granules remain an enigma, cloaked in biological mystery, yet they could represent an era of heightened metabolism, a preparatory surge readying the astrocytes for subsequent exponential growth. Like seeds poised to burst forth from the earth, the granules may be indicators of an impending flourish, a precursor to a complex symphony of cellular and molecular syntheses. As this journey through cellular evolution unfolds, one cannot help but marvel at the parallelism of life – the microcosmic struggles and triumphs akin to those in the vast universe beyond. Whether in stillness or dynamic change, the story of these astrocytes resonates deeply, a reminder of the relentless energy driving life forward, both within and around astrocytes.

On days 7 and 8, our exploration revealed an intricate sea of cellular activity within the culture flasks, highlighted by the lush cell cytoplasm and notable signs of growth and maturation. The cells showcased significant granulation and interconnections that hinted at a transformative phase in their development. As we advanced to day 9, the human astrocytes manifested an intriguing abundance of fibrillary content, their appearance punctuated by delicate, whitish appendages—often linear—that cast a fascinating silhouette against the vibrant intercellular landscape. These linear extensions appear to signal a critical aspect of astrocyte matrix organization, reflective of their evolving complexity and maturity. The morphology observed allows research scientists to postulate a deeper understanding of the astrocytic roles in neural environments. This research engaged in a nuanced discussion about the precise timing of confluence; while the vibrant images and slides suggest an ongoing transition, pre-culture investigations strongly indicate day 9 as the definitive confluence point. Herein lies the confluence of observation and interpretation, weaving together the narrative of cellular evolution as we stand at the cusp of understanding the rich tapestry of neuroglial biology. Each day—a story revealed, underscoring the dynamic interplay of maturation, complexity, and the organization that defines the life of astrocytes in culture.

In examining the series of microscopic images captured over the course of eleven days, a remarkable transformation in the cellular landscape becomes evident—particularly on day 10. The appearance of numerous vesicles contrasts sharply with the scant presence noted in the early images, spanning days 1 through 9. These vesicles, typically indicative of cellular processes associated with communication and transport, signal a shift in the state of the cells under observation. Moreover, the image on day 10 exhibits pronounced turbidity and subtle discoloration in the slides, characteristics traditionally associated with the aging process. This alteration could suggest a decline in cellular integrity or an accumulation of metabolic byproducts, both of which serve as robust markers of waning cellular health.

The insights take a more dramatic turn on day 11. Here, the microscopic realm reveals an even further advancement in these traits: vacuoles emerge alongside conspicuous empty spaces within the culture area, echoing conditions akin to astrogliosis witnessed in brain tissues under stress. The presence of vacuoles commonly indicates intracellular changes as the cells arguably react to injury or metabolic disturbance. These findings compel further scrutiny and underscore the importance of real-time monitoring in understanding the evolution of cellular architecture over time, particularly in the context of neurodegenerative diseases or age-related declines. The images serve as a compelling visual narrative, cataloging the intricate and often unraveling stories etched within each cell as they navigate the currents of aging challenges.

3.3 GDH Isoenzymes and Cell Images: This study observed a distinct variation in the isoenzyme patterns of Glutamate dehydrogenase (GDH) between two control groups, underscored in Figure 5. Control A, evaluated at day 9, displayed a unique GDH isoenzyme profile that markedly contrasts with the pattern recorded for Control B at day 11. This visual representation not only highlights the differences in isoenzyme distribution between the two controls but also integrates accompanying cell images. For Control A at day 9, the cell imagery reveals a robust cellular landscape, resonating with the prominent GDH activity, while Control B at day 11 presents a different cellular architecture, correlating with its altered GDH isoenzyme expression. The juxtaposition of isoenzyme patterns alongside visual cellular context allows for a comprehensive understanding of the metabolic variations at play. Ultimately, Figure 5 serves as a critical point of reference in elucidating the biochemical dynamics emerging from the experimental controls on specific developmental timelines.

Figure 5

 

Legend to Figure 5: Image comparing the GDH Isoenzyme Fingerprint for Control A (at Confluency) and Control B (at 2 days post Confluency). This unique unprecedented 4 image comparison pattern presented here are the hallmark of the correlation between change in GDH fingerprint and Astrocyte cellular morphologic changes.  The first roll shows the GDH hexameric redox cycle isoenzyme distribution pattern as photo-documented for control A (day 9) and for control B (day 11) after dialyzed Rotofor fractions were subjected to Laemmli SDS 12% polyacrylamide gel electrophoresis (PAGE) (100 V, 14 h, 4˚C) to remove other proteins and nucleic acids. Notice the difference in the GDH isoenzyme fingerprint pattern The second roll shows the electron micrographs for control A (day 9) and control B (day 11) side-by-side. Notice the difference in the micrograph on day 9 showing mature health Astrocyte culture and the micrograph on day 11 showing older and degenerating Astrocyte culture. The post confluency astrocyte cells were more complicated phenotypically than the cells at confluency. Also, the GDH hexameric isoenzyme distribution pattern was more complicated in the post confluency astrocyte cells (Control B) than in the cells at confluency (Control A).

 

3.4 GDH Isoenzyme Pattern Results: Whereas the electron micrographic images of the human astrocyte cells at confluency (Control A, day 9) and at post-confluency (Control B, day 11) were the real life snap shots of the otherwise transient imperceptible morphological transition from one stage of growth to the next; the GDH hexameric isoenzyme distribution patterns provided the unequivocal peep into the behind-the-scene biochemical changes that triggered the morphological transitions. The post confluency astrocyte cells were more complicated phenotypically than the cells at confluency. Also, the GDH hexameric isoenzyme distribution pattern was more complicated in the post confluency astrocyte cells (Control B) than in the cells at confluency (Control A). There were merely two rows of the hexameric isoenzymes at the confluency growth stage, but there were three rows of the hexameric isoenzymes at the post confluency growth step. It is generally difficult to demonstrate independent visual lines of corroborative evidence in support of biological phenomena, but here the hexameric isoenzymes of GDH have converged with the human astrocyte morphological transition to reveal the function of the enzyme at the molecular level [65, 66].

 

4.0 Reliability and Reproducibility Experimental Design: The purpose of an experimental design is to improve reproducibility, minimize variability between observers, and generate valid results through the systematic application of interventions while keeping other variables constant in the control group. [67, 68, 69] It is not sufficient for experiments to be designed solely to fulfill statistical requirements by creating triplicates to demonstrate measures of central tendency such as means, standard deviations, and more for a set of data, without addressing the scientific question for which the experiment was designed [70]. Unfortunately, this is often the case with many biological culture experiments. As a result, the use of triplicates in cell culture protocols is now being questioned. Singer, J.M., et al [67] have demonstrated that when the intraclass correlation coefficient (cf) exceeds 75% (0.75), there is no added benefit to conducting triplicate observations. [67, 68, 69] In this study, the correlation coefficient of >0.99, disfavors the use of triplicates. A preliminary study can be conducted to determine whether it is appropriate to omit triplicate designs when a strong correlation is expected, as done in this study.

In cellular biology, the significance of reproducible outcomes cannot be overstated. When examining the replication of cell cultures from the same or closely related cell lines, especially under rigorously controlled growth protocols, research scientists can anticipate a strong correlation coefficient that reflects the reliability of their experimental setup. This study meticulously crafted to highlight this premise reveals that Human Astrocyte Cultures (HAC) derived from iXcells adhere consistently to a markedly predictable growth trajectory. This observation holds true across the board provided the culture conditions remain identical and the methodological protocols are uniformly applied.

In this experiments, the protocol meticulously controlled factors such as nutrient supply, environmental conditions, and passage rates to establish a robust framework. The results not only illustrate the stability and repeatability of HAC growth patterns but also supports the dependability of the study design  [68. 69]. Enhanced understanding of these predictable behaviors opens avenues for further exploration into the biological processes at play, and can push the boundaries of what we know about cell growth dynamics. The demonstrated correlation corroborates previous research and serves as a powerful reminder of the importance of standardized methodology in cellular experiments [68, 69]. The findings fortify the notion that reproducibility in human astrocyte cell research is not merely an aspiration but an achievable standard that leads to credible scientific discourse and progress.

The reliability and reproducibility of this study are robustly underpinned by design of meticulous observational framework which involved a comparative analysis of the progress and physical characteristics of cultures in Group A and Group B. Everyday phase-contrast electron micrographs images of the cells captures the growth stages, providing a wealth of visual data for rigorous comparison between the groups, and between observations from the preceding days (Fig.3).

This process of regular documentation was not merely procedural; it was essential in revealing emerging trends in growth dynamics. By systematically tracking the evolution of the cultures through both qualitative and quantitative means, this helped to discern patterns that might otherwise have gone unnoticed. The consistent application of this observational strategy highlighted differences and similarities in cell morphology and development rates between the two groups, thus enriching our understanding of the underlying biological phenomena. These insights will not only bolster the credibility of the findings but also pave the way for future research aimed at exploring the intricacies of cellular growth and differentiation within similar experimental contexts. [68, 69, 70] The robustness of these findings, provide a solid foundation for future research in this research domain. The meticulous design of our experiment, incorporating both intra-experiment controls and references to well established standards reveals a commitment to rigorous scientific methodology. the consistency observed across different experimental conditions not only corroborates previously published results but also elevates the reliability of current data. Figures sift through the experimental periods like reliable narratives, each depicting growth trajectory that align closely with the normative benchmarks set forth by iXcells Biotech (fig. 2, fig. 3). This harmonious synergy between the findings here and external standards serves to enhance the credibility of current approach and outcomes. Moreover, the sophisticated interplay of concurrent controls allowed us to identify subtle nuances in cell behavior, fostering a deeper understanding of the underlying biological mechanisms. Each harvested data point emerged as a testament to the rigor of this research design, compelling us to affirm that the laboratory methodologies here adhered to the highest standards of scientific protocols. With these encouraging results, research aims to pave new pathways for exploratory studies, offering fertile ground for investigating innovative therapeutic avenues and interventions.

The outcomes delineated in this study not only reinforce established hypotheses within the field but also invite future research scientists to delve further into the intricacies of human astrocyte biology, emboldened by a framework that values reproducibility and discovery rather than one that dwels on statistical figures. The journey from hypotheses to problem solving has only just begun, and expectations are poised to soar higher than ever before in the pursuit of knowledge. In practical terms, this means that each phase of experiment is interconnected, enabling real-time monitoring and quick adjustments to protocols as needed. With meticulously tracked responses and validated outcomes against established benchmarks, the data’s accuracy is assured. Through rigorous standardization of procedures and comprehensive data analysis practices, we create a strategic environment that bolsters the scientific credibility of experimental investigations. As we move forward, this innovative approach will serve as a cornerstone for future research endeavors, paving the way for breakthrough discoveries and a deeper understanding of cellular behaviors in response to different pharmacological agents. In essence, this current design not only addresses immediate experimental needs but also enhances the foundational principles of scientific inquiry, echoing through future studies and fostering a culture of precision and accountability within the field.

As the scientific community grapples with the complex issue of improving reproducibility in in vitro studies, this thorough and innovative approach stands as a promising solution. This began with a clearly articulated experimental design that prioritized the inclusion of robust internal controls and the utilization of comparable external choices. In tandem, we engaged in daily microscopic imaging, allowing for direct visual observations that brought an additional layer of scrutiny to the experimental data collection process. Thus results from this experiments speak volumes, with a striking correlation coefficient exceeding 0.99—indicative of the robust reliability and reproducibility. [68,69,70] While we acknowledge the valuable recommendations posited by scholars such as Niepel, M. et al., and Hirsh, C. & Schildknecht, S., [68,69] this current contribution is not merely complementary, but this methodology offers necessary advancements that simplify procedural designs, addressing the very heart of reproducibility without undermining existing protocols.

One of the key dividends of this approach is the significant reduction of costs associated with unnecessary biological and technical replicates. Traditionally, the focus on creating multiple iterations of experiments has often become an exercise in measuring central tendencies, yielding little more than data redundancy that teaches us little about the underlying phenomena at hand. By streamlining these elements, scientists can redirect their focus towards pivotal research objectives, fostering both efficiency and clarity in the quest for meaningful scientific inquiry. In doing so, we strive to bolster the collective endeavor towards enhanced reproducibility in cellular research, advocating for practices that not only comply with accepted standards but strive to elevate them. As the future turns, the hope is to inspire other research scientist to adopt similarly rigorous yet simplified strategies to advance the field with findings that can be trust and reproducible like this..

The distinction between technical replicates and biological replicates is of paramount importance and can significantly impact the validity of experimental conclusions. Oftentimes, studies claim to utilize triplicate designs; however, these frequently do not fulfill the true criteria for biological replicates. To accurately reflect biological variability, researchers ideally should employ cells from different progenitor cell lines within the same experiment. Unfortunately, this ideal is not realized in practice. [69,70,71] To illustrate, consider a hypothetical experiment claiming to assess cellular responses using a triplicate design deploying the same cell line across 96 wells. While this setup may yield consistent readings, it will fail to capture the biological diversity that arises from different progenitors, which may lead to conclusions that lack broader applicability. When the biological landscape under investigation does not encapsulate the array of related cell types, extrapolating results to imply comprehensive insights across similar cell lines becomes inherently flawed.

Recognizing these limitations, we focused this experiment on leveraging a single, consistent cell line—the A-172 Astrocyte cell line [27, 28, 30, 31, 32]. By maintaining a homogeneous source in our study as referenced in benchmarks [27, 28, 30, 31, 32], we ensured a controlled environment where cellular variability attributable to differing progenitors is mitigated. While this approach limits the representation of biological diversity, it allows us to confidently address the specific question of cell line behavior with a high degree of consistency. Thus, this choice facilitates a clearer, more reliable understanding of the underlying cellular mechanisms and avoiding confounding influences of unrelated progenitor variations. This strategic decision ultimately serves to enhance the rigor and precision of the findings, allowing scientists to draw more confident conclusions within the confines of biological culture in general and human astrocyte experiments in particular. In cellular research, consistency is the bedrock upon which robust conclusions are built. This study adopted a prudent approach by employing cells exclusively derived from the A-172 astrocyte cell line, ensuring that all experimental variants stemmed from the same progenitor source. Using a homogenous cell culture provided a platform for more reliable data interpretation, laying to rest the questions surrounding inconsistencies that can arise when different cell lines are utilized. By focusing on the A-172 astrocytes across multiple assessments, we aimed to isolate the findings from the misleading intricacies of cellular heterogeneity. The exclusive conclusion from the A-172 human Astrocyte cell lineage [27, 28, 30, 31, 32], offered a clearer lens through which to examine the key hypotheses of this study. 

4.1 Generalizability of Results: When conducting scientific research, the significance of a sample's generalizability cannot be overstated. The conclusions drawn from an experiment can only be confidently applied to a broader context when the sample accurately represents the targeted population. In this study, the samples were carefully selected from the Human Astrocyte Cell (HAC) line, ensuring that the findings are highly relevant and applicable within this specific experimental framework. Central to this investigation were high-quality primary human astrocyte cell lines sourced from iXcells Biotechnologies. These vital cell line originated from the cerebral cortex of the human brain and were meticulously isolated before being cryopreserved at passage 2 (P2), offering the ideal balance of viability and authenticity necessary for robust experimentation [31, 72].

This methodological rigor, combined with strong internal consistency observed throughout the experiments, fortifies the applicability of the results to follow-up studies involving digits from other HAC line experiments. As we navigate the intricate landscape of cellular behavior and responses, it is this foundation of reliability that allows us to explore broader implications and delve deeper into the neuronal intricacies of human health and disease. The alignment of our sample with the real anatomical and biochemical landscape of the brain accentuates the importance of the findings, signaling a step forward in the understanding of astrocytic function in various neurobiological contexts.

The A-172 Astrocyte cell line emerges as a notable subject due to its distinct expression of Glial Fibrillary Acidic Protein (GFAP). This hallmark characteristic not only affirm the identity of the A-172 cells but also sets a benchmark for comparative studies. [31, 33, 37] In contrast, the murky waters of malignant astrocytoma introduce the U-87MG cell line, [33] clinched from grade III tumors, which serves as the alternate primary astrocyte model predominantly featurs in cancer research. The U-87MG cells underscore the formidable nature of aggressive astrocytic tumors and their implications in therapeutic investigations [31]. These U-87MG cells were not used in this study.

Thus, this study sample was derived from the A-172 primary astrocyte cell line, a pivotal choice for exploring the complexities of human astrocyte culture. This cell line served as a representative model, allowing scientists to delve deeper into the physiological and pathological roles of astrocytes in the human brain. Consequently, the findings can be effectively generalized to experiments utilizing this specific cell line, fostering a better understanding of how astrocytes contribute to both normal brain function and various neurological disorders. With the nuanced insights gained from this current research, research aims to illuminate the critical interplay between astrocytes and neurons, paving the way for innovative therapeutic strategies aimed at addressing brain-related ailments. In the delicate dance of cellular life, the A-172 human astrocytes illustrate an enigmatic journey governed by both invisible threads of genetic coding and the palpable forces of their environment. When research meticulously control conditions—ensuring a harmonious balance of temperature, humidity, nutrient media, and pH—these astrocytes flourish, following an almost preordained rhythm. They grow, they mature, and then, like a once-vibrant autumn, they eventually succumb to the inevitabilities of aging and death. Yet, this dance is choreographed by more than just the sequence of genetic information. As we delve into the intricate tapestry of astrocyte life cycles, research unearths a compelling narrative—one that suggests environmental determinants play a pivotal role alongside genetic programming. The assumption that genetics alone dictates growth trajectories appears simplistically reductive in light of the evidence suggesting that environmental signals can either amplify or suppress the vibrancy of these cells [48]. Indeed, under less than ideal conditions, the anticipated vivacity of growth stumbles, demonstrating that genetics alone cannot be the commander of this orchestra. Optimal environmental cues seem to unlock genetic expressions, illuminating a path for growth that remains hidden in their absence. Thus, science finds itself at the crossroads of biology’s great mystery—forever seeking clarity on the entwined fates of astrocyte growth, maturity, aging, and death, mechanisms shaped by an ongoing dialogue between genetic predisposition and environmental resilience. This revelation not only challenges existing paradigms but also invites us into a universe of unexplored potentials—a canvas where the art of life is painted with both genetic and environmental strokes, the outcome a beautiful synthesis of resilience, adaptation, and precedence. Environmental signaling is an intricate phenomenon between cells and their surroundings, an essential mechanism that transcends the confines of genetic blueprints. As detailed by Osuji and Okea (2024), [48] it plays a crucial role in the arduous journey of growth, preservation, and ultimately, the life cycle of organisms. The scientific community continues to unravel the complexities of how these signals influence cellular behavior, triggering pivotal processes from maturation to programmed cell death.

In this quest for understanding, one fascination shines through: GDH (Glutamate Dehydrogenase) hexameric isozymes. These remarkable enzymes not only reprogram cell metabolism in harmony with environmental cues but also display the extraordinary capability of synthesizing RNA independent of genetic code. Such dual functionality opens a window into cellular adaptability, heralding a new era of research into how organisms navigate the often-turbulent waters of their ecosystems. The discovery of GDH's mechanisms. reveals that environmental modulation is not merely an abstract idea but a concrete biological reality. [48,62,53]  The hexameric structure of GDH is suggestive of its complex interaction with metabolic pathways, responding astutely to varying conditions by adjusting the flow of resources to meet cellular demands. Furthermore, its ability to synthesize RNA highlights an intriguing layer of autonomy, suggesting that cells possess an intrinsic capability for self-regulatory feedback mediated by external factors. This insight offers profound implications for our understanding of metabolism, growth control, and longevity.

As we continue to explore these mechanisms, the intersection of GDH activity and environmental signaling promises to illuminate the pathways that sustain life. Bridging molecular biology with ecological strategy, science inch closer to deciphering how life flourishes amid the constant ebb and flow of its environment. The continuing research led by scientists like Osuji GO and Okea RN (2024) [48] and points towards a future rich with discovery, as science grasp at the threads connecting genetic expression, cellular responses, and the ever-dynamic confluence of life's myriad signals. This intricate non-genetic controls of life unfolds at the microscopic level, particularly within the human astrocyte cell lines under study. Though these human astrocyte cells serve as laboratory protagonists, the narrative transcends them, encapsulating a broader theme of metamorphosis — the remarkable transformations that all cells experience throughout maturity and as the sands of time trickle away. What truly captivates the attention here are the empirical revelations concerning the hexameric isoenzyme pattern of Glutamate Dehydrogenase (GHD), a molecular architect that orchestrates this metamorphosis. Imagine GHD functioning as both a gatekeeper and a guide, regulating the symphony of cell transformations, mechanisms of aging, and the metabolism that fuels cellular vitality. This complex interplay hints at something profound: the ability to reprogram cellular function is not shackled to the blueprint of genetics or genomics but is rather pliant, responsive to the whispers of environmental signals. As observed in the research led by Osuji and Okea (2024), the role of GDH becomes unmistakably pivotal in the biochemical landscape of cell metabolism. Its presence, ubiquitous across all animal cells, reinforced the notion that this enzyme wheeled more than mere metabolic duties; it navigated the pathways of change, orchestrating harmony amid the chaos of cellular evolution.

From this perspective, we discern a fundamental truth: that cells are not mere vessels bound by genetic fate; they are dynamic entities, responsive to their surroundings, capable of growth, renewal, and adaptation. In essence, GDH stands as a beacon of cellular potential, illuminating the epic journey through which cells can metamorphosize and thrive, charting a course crafted by circumstance rather than just the confines of inherited DNA. Thus, as trsearch delves deeper into this minuscule yet grand voyage of cellular transformation, we uncover layers upon layers of complexity, beckoning further exploration and illuminating the awe-inspiring potential woven into the fabric of life itself. Nature has intricately woven enzymes that serve not merely as catalysts, but as vital messengers of metabolic equilibrium. Among these, Glutamate Dehydrogenase (GDH) stands out as a quintessential player, reflecting the dynamic and often tumultuous landscapes of cellular life. [53, 73, 74, 75, 76, 77, 78, 79.].

The chemistry surrounding the GDH isoenzyme complex presents a fascinating paradigm of precision. It is not merely a product of simple chemical interactions, but an exact science that speaks to the fundamental processes of life. As cells undergo transitions—whether gracefully maturing or inevitably aging—the GDH isoenzyme pattern reveals a responsive narrative of change. Each shift is a testament to the cell's adaptation to its environment, echoing across species and cultures, highlighting a universal phenomenon in cellular behavior. Irrespective of the chosen cell culture techniques or environmental constraints, this characteristic remains consistent. The alterations in GDH isoenzyme expression are generalizable principles of cellular metabolism, portraying an intricate complex of bioenergetics at play. As illustrated by the findings of Osuji and Okea (2024), [48]  the evolution of GDH throughout these transitions serves as a critical fingerprint for understanding not only individual cell functionality but also the organism's resilience—and perhaps vulnerability—against the trials of life. In the quest for knowledge, this enzyme's story unfolds, bridging gaps in our understanding of cellular aging and maturity, painting a vivid picture of life’s relentless cycles.

4.2 GDH Isoenzymes Patterns: GDH is encoded by two nonallelic genes (GHD 1  and GDH 2 ) with GDH 1  encoding the more acidic polypeptides (a) and (α), being heterozygous and codominant; and GDH 2  encoding the less acidic polypeptide (β) being homozygous (Cammaerts and Jacobs 1983). [65] The binomial distribution of the three types of polypeptides gives rise to the complex system of hexameric isoenzymes. In the human laryngeal epithelial cells, the GDH was readily resolved to 28 hexameric isoenzymes (Osuji et al., 2021) [62] here in the human astrocyte cells (Figure 6), the hexameric GDH isoenzymes numbered about 13 for the Control A but were up to 18 for the Control B judging from the standard statistical binomial distribution pattern (Figure 6). This is evidence for the tissue specificity of the biological function of the enzyme. The differences of the numbers of the hexameric isoenzymes show that GDH responds to the cues of growth and development manifested as the transition from confluency to post confluency. As an aim of this experiment was to define the chemical basis of cellular maturity in human health and disease conditions, the involvement of GDH in the morphological change of human astrocyte cells has interjected far-reaching implications on the practice of molecular cell biology. Changes in the numbers of the hexameric isoenzymes of GDH are caused by chemical reaction (Osuji et al., 1999). [66] It is an exact chemical event as Figure 5 unequivocally demonstrated, not by sciences that are beclouded in uncertainties and statistical probabilities because no number of triplicate repeats of the cell culture protocols would have altered the GDH fingerprints. [67, 68]

 

Fugure 6

Binomial Statistical Distribution of the α, A, and B subunits in the

Hexameric structure of the glutamate dehydrogenase isoenzymes

 

αααααα           αααααB           ααααBB           αααBBB           ααBBBB           αBBBBB BBBBBB       

AAAAAA         AAAAAB         AAAABB          AAABBB          AABBBB          ABBBBB

αααααA          ααααAB          ααAABB          αAABBB          αABBBB

ααααAA          αααAAB          ααAABB          αAABBB

αααAAA          ααAAAB          αAAABB         

ααAAAA          αAAAAB         

αAAAAA

The A, and α subunits are more acidic than the B subunit

 

 

Legend to Figure 6: Binomial Statistical Distribution of the α, A, and B subunits in the Hexameric structure of the glutamate dehydrogenase isoenzymes. GDH is encoded by two nonallelic genes (GHD 1  and GDH 2 ) with GDH 1  encoding the more acidic polypeptides (A) and (α), being heterozygous and codominant; and GDH 2  encoding the less acidic polypeptide (B) being homozygous (Cammaerts and Jacobs 1983). [65] The binomial distribution of the three types of polypeptides gives rise to the complex system of hexameric isoenzymes. In the human laryngeal epithelial cells for example, the GDH was readily resolved to 28 hexameric isoenzymes (Osuji et al., 2021) [62] here in the human astrocyte cells, the hexameric GDH isoenzymes numbered about 13 for the Control A but were up to 18 for the Control B judging from the standard statistical binomial distribution pattern (Figure 6). This is evidence for the tissue specificity of the biological function of the enzyme. The differences of the numbers of the hexameric isoenzymes show that GDH responds to the cues of growth and development manifested as the transition from confluency to post confluency. Changes in the numbers of the hexameric isoenzymes of GDH are caused by chemical reaction (Osuji et al., 1999). [66] It is an exact chemical event as Figure 5 unequivocally demonstrated, and no number of triplicate repeats of the cell culture protocols would have altered the GDH fingerprints. [67, 68]

 

5.0 Discussion

5.1 Pre-Clinical Implication: The results from this study clearly demonstrated unequivocally the tissue specificity of NADH-GDH isoenzyme fingerprints in human astrocyte cell culture, consistent with findings from human laryngeal cell culture and, indeed, with any cell culture. [48]

5.11 Usefulness of NADH-GDH Isoenzyme in Cell and Molecular Biology: In the evolving landscape of cell and molecular biology, the utilization of NADH-GDH isoenzyme fingerprinting emerges as a groundbreaking methodology with the potential to rewire our understanding of cellular identity. By establishing a unique fingerprint for each isoenzyme variant for specific tissues, research scientists will gain a powerful ally in distinguishing between different cell types and will better understanding their distinctive roles in biological contexts of time, space and environment. [48, 49, 82]

Imagine a framework where cell typing transcends mere morphological observation, or where cell identity fingerprinting serves as a lens through which the unique signatures of cells metabolism can be captured, our understanding of the real complexity of biology will supersede just a mere explanation of cell genetics. Such advancements can empower scientists to embark on intricate tissue mapping endeavors, revealing how specific cells contribute to the architecture of a tissue and of whole organism. The creation of comprehensive NADH-GDH fingerprint databases could become an invaluable repository, a treasure trove of cellular information detailing not only genetic markers but also the biochemical adaptations cells undergo in response to their ever changing environments. [48, 49, 80]

The implications of such tools are profound, by exhuming the unique micro-molecular footprints—echoed in NADH-GDH activity—of biological cells, research scientists can delineate patterns crafted by the interplay of intrinsic genetic codes and the extrinsic physical, chemical, and electromagnetic realms that concurrently influence cellular functionality. This intricate cell typing will paint a vivid picture, allowing for the definition of cells and tissues in time and space based on their specific GDH isoenzyme characteristics, thus heralding the dawn of precise and nuanced categorization that incorporates not only structure but also molecular function. [48, 81]

Moreover, the advent of such methodologies will give rise to a new field likened to cell and tissue forensic biology, a frontier dedicated to elucidating the lineage of cells and tissues through their specified activity of GDH isoenzyme patterns in both environmental time and space. This discipline promises to enhance our capabilities in diagnostics, forensics, and therapeutic strategies, equipping scientists and clinicians with the tools to probe deeper into the biological narratives that lie beneath each microscopic structure.

Thus, NADH-GDH isoenzyme fingerprinting does not merely represent a tool; it symbolizes a paradigm shift in our conceptualization of biology, inviting an era where the integrity and identity of biological samples can be traced back with unparalleled accuracy, in a unique cellular process waiting to be unraveled. In exploring this innovative path, we not only elevate our comprehension of diversity within cells and tissues, but we may also unlock novel therapeutic interventions, tailor individualized medicine, and reshape our interactions with biology at the most elemental level. [48, 49, 80, 81]

5.2 The Transformative Role of NADH-GDH Isoenzymes in Pharmacology and Drug Metabolism: The NADH-GDH isoenzymes offer an extraordinary glimpse into the profound complexities of cellular chemistry. From their captivating fingerprints, we begin to unveil the unseen yet critical molecular reactions that occur within cells and tissues. Notably, the NADH-GDH isoenzyme synthesizes a novel form of gene-independent RNA known as Chimerenomic-RNA, a pioneering identity in the realm of pharmacological research (Osuji and Okea, 2024). [48]

In a research paper published in 2008, Osuji et al. [49] elucidated how these isoenzymes navigate drug metabolism by orchestrating the regulation of messenger RNAs (mRNAs) that are tasked with encoding vital drug-metabolizing proteins. The elucidated role of Chimerenomic-RNA in temporal modulation of mRNAs sheds light on several key players in drug metabolism, including Cytochrome P450 reductase (CPR), Superoxide dismutase (SOD), and various transporters, among others (Osuji et al., 2008). [49] Understanding this intricate web of interactions not only enhances our grasp of metabolic pathways but reveals how NADH-GDH isoenzymes can potentially influence pharmacokinetics and pharmacodynamics across a wide spectrum of therapeutic agents. Cytochrome P450 plays a role in near 80% to 90 % of all drug metabolism [82, 83], yet NADH-GDH synthesized chimerenomic-RNA controls and is able to reprogram genetic-based mRNAs encoding CPR; therefore just through this pathway, chimerenomic-RNAs, a product of NADH-GHD isoenzyme complex, modulates 80% to 90% of drug metabolism. [48, 49, 82, 83] The modulation of CPR is albeit not the only function of chimerenomic-RNA in drug metabolism, but affects practically all the drug metabolizing enzymes.

This breakthrough realization signals the dawn of a new era in both pharmacology and pharmacotherapy, where scientists now have the opportunity to modify the functional impacts of drug side effects by actively applying the knowledge derived from GDH isoenzyme fingerprints and their corresponding chimerenomic-RNA. [48, 49] With this refined understanding, we can envision novel targeted interventions aimed at mitigating adverse drug reactions, particularly in organs susceptible to toxicity such as the liver, kidneys and brain. By leveraging the therapeutic potential of these isoenzymes, we can pave the way for innovative tactics to counteract hepatotoxicity, nephrotoxicity, and central nervous system toxicities.

At the forefront of these possibilities is CPR, the linchpin in the biotransformation of around 80% to 90% of all pharmaceuticals (Zhao et al., 2021; Lynch and Price, 2007). [82, 83] The remarkable ability of GDH isoenzymes to enhance CPR expression presents an unparalleled tool in the modulation of drug metabolism, potentially minimizing toxicity risks. Traditional genetic testing protocols aiming to identify CPR functional defects could be revolutionized by employing cell and tissue-specific GDH fingerprints, offering a practical and therapeutic-led diagnostic approach to rectify metabolic inadequacies.

Additionally, NADH-GDH isoenzymes exhibit significant regulatory capabilities over copper/zinc superoxide dismutase (SOD) mRNA, an indispensable component of the body's antioxidant defense system. [49] This interrelationship becomes especially relevant in the context of neurodegenerative conditions, such as familial amyotrophic lateral sclerosis (ALS)—where mutated SOD genes contribute to about 25% of familial cases—hinting at GDH's potential role in both ALS therapeutics and research (Osuji et al., 2008). [49] Herein lies a captivating narrative: the detoxification of perilous superoxide free radicals by chimerenomic RNA-linked regulation strengthens the argument for GDH isoenzyme involvement in safeguarding cellular integrity during drug metabolism.

Also GDH regulates the activities of many other diverse drug metabolizing enzymes, including Alternative Oxidase, Glutathione S-Transferase, Acid Lipase Transporter, ABC Transporters, Proton Pump enzymes, as well as essential genes related to Flavonoid Biosynthesis and the 28S rRNA gene, aside the regulation of many transcriptional and translational factors (Osuji et al., 2008). [49]

Moreover, the regulatory influence of GDH isoenzymes extends across multiple metabolic processes involving critical enzymes, paving the way for a radical rethinking of how drugs and xenobiotics are metabolized within biological systems. The capacity of these isoenzymes to remodel metabolic pathways upon exposure presents researchers with a rare opportunity—to illuminate uncharted territories in the mitigation of drug-induced adverse effects and environmental toxins.

The burgeoning understanding of NADH-GDH isoenzymes beckons further inquiry, inviting us to embrace the potential they harbor in crafting novel antidotal agents and innovative therapies. With this knowledge, we stand at the threshold of seemingly endless possibilities for enhancing patient care, illuminating the intricate connections between molecular function and clinical efficacy, and establishing a transformative blueprint for the future of pharmacology. As we continue to unravel the fascinating new reality of drug metabolism, the potential held by NADH-GDH isoenzymes represents both an opportunity and responsibility for the pharmacological community, inspiring us to pioneer solutions to some of our most pressing health challenges.

5.3 Innovative Approaches in Disease Diagnosis Using NADH-GDH Isoenzyme Fingerprinting and Chimerenomic RNA Analysis: The precision of disease diagnosis has significantly evolved, paving the way for advanced biomarker identification and non-invasive testing techniques. One such pioneering approach involves the utilization of NADH-GDH isoenzyme fingerprinting. This method reveals a biochemical signature unique to various human diseases, whether they arise from genetic mutations, metabolic dysfunctions, or environmental influences. By meticulously analyzing the patterns generated through this innovative technique, diseases can now be diagnosed with unprecedented specificity. [48]

Research outlined by Osuji and Okea (2024) showcases how amassing knowledge from chimerenomic RNA synthesized by GDH allows for a homology analysis with mRNA, rRNA, or mitochondrial RNA associated with particular disease states. This method not only enhances diagnostic accuracy but also enriches our understanding of the genesis of various conditions such as Alzheimer's disease. Remarkably, this technique could facilitate prediction of Alzheimer’s risks, often long before its clinical symptoms become apparent, opening doors for earlier interventions and potentially altering the trajectory of the disease's progression. Using chimerenomic homology, potentially the diagnosis and treatment for Alzheimer’s disease is within grasp. This study on human astrocytes has illuminated the potential for the diagnosis and treatment of Alzheimer’s disease and other neurodegenerative diseases. [84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95, 96]

Furthermore, these advances are mirrored in the diagnosis of amyotrophic lateral sclerosis (ALS) [85]. Previous research indicated through chimerenomic homology studies that familial ALS can now be flagged with the NADH-GDH isoenzyme fingerprint. [49] The implications are substantial; patients and healthcare providers gain access to tools that refine diagnostic processes, leading to timely treatments and better patient outcomes.

Beyond neurodegenerative diseases, the utilization of the GDH fingerprint extends to a myriad of genetic disorders such as sickle cell disease, hemoglobinopathies, thalassemia, and hemophilia among others. By comparing a patient’s specimen against the established GDH fingerprint signatures for these and any condition, accurate diagnoses can be achieved swiftly, alleviating the lengthy traditional methods often burdened by complications. Now treatment of many of these conditions are attainable

This diagnostic breakthrough also carries significant applications in the field of metabolic diseases, including diabetes and hyperlipidemia. The detailed biochemical information extracted via GDH framework allows for targeted treatments, individualized patient care, and effective management strategies.

Moreover, the landscape of oncology stands to be transformed with the introduction of this technique. The NADH-GDH isoenzyme fingerprint will play a pivotal role in diagnosing cancer, whereby purified fingerprints of cancer cells are generated, and synthesized chimerenomic RNA can serve as sensitive probes. This will enable comprehensive screenings to determine the presence or absence of malignant cells in both serum and tissue specimens.

Thus the integration of NADH-GDH isoenzyme fingerprinting and chimerenomic RNA analysis will herald a new era in disease diagnosis and treatment. With such promising methodologies, clinicians and researchers can strategically navigate complex disease pathways – embracing a future characterized by sophisticated, accurate, and preventive healthcare solutions.

5.4 Unleashing Chimerenomic Medicine: A Revolutionary Approach to Treatment: Every physiologic and pathologic event within cells and tissues are influenced by both internal and external environments. At the heart of this dynamic process lies the NADH-GDH isoenzyme system—a natural mechanism meticulously crafted to modulate, correct, and repair deviations from our body's optimal state. This marvelous system reprograms cellular functions, guiding them back to their original healthy states, culminating in continuous cellular healing through biomolecular reprogramming.

Emerging research demonstrates that a wide array of disease conditions inscribe their unique repair signatures within the chimerenomic RNA sequences of NADH-GDH isoenzymes. When research delved into the molecular drama of disease progression, it discovers homologous mRNAs encoding the proteins associated with various disease conditions and that, these genetic-code mRNAs, serves as substrates for the chimerenomic-RNA enzymes produced by these NADH-GDH hexameric isoenzymes. These Chimerenomic-RNA enzymes act like master key holders, swiftly digesting genetic code-based RNAs that cause pathology and thereby clearing the way for restoration and healing.

By unlocking the power of chimerenomic medicine, we stand on the threshold of transformative breakthroughs for treatments targeting formidable conditions such as Alzheimer’s disease, Amyotrophic Lateral Sclerosis (ALS), Multiple Sclerosis, Diabetes, Sickle Cell Anemia, Hemophilia, and a plethora of autoimmune disorders. These diseases are often precipitated by recognizable mRNAs pathways that can now be explored with remarkable clarity and efficiency. [48, 49, 80]

On the front lines of cancer treatment, this innovative discovery has illuminated opportunities for interventions targeting specific genes and their corresponding mRNAs; and environmental carcinogens and bio-oncogenic mechanisms. By honing in on malignancies such as breast, cervical, lung, colon, pancreatic, renal, and CNS cancers, chimerenomic medicine can re-envision therapeutic strategies: not only for detection but also for complete eradication, leveraging the powerful specificity of chimerenomic RNA parallels.

But the reach of this technique extends beyond chronic disease; its implications for infectious diseases are even more formidable. Viruses and bacteria manipulate cellular metabolism primarily by reprogramming RNA and gene expression, altering biological pathways critical for health. Here, the NADH-GDH isoenzyme chimerenomic system proves invaluable. It has the potential to target defective genes and suppressed RNA types (often spawned from persistent infections) efficiently neutralizing them and halting prevailing disease mechanisms—regardless of infection duration.

This novel estrangement from traditional antibiotics driven treatment heralds a far-reaching tool against a range of infectious diseases—including emerging pathogens and potential pandemic threats. With the understanding of chimerenomic medicine, research can glimpse a future where prevention is as much within our reach as a cure, redefining the trajectories of human health amid challenges posed by chronic and infectious diseases alike.

The ramifications of understanding and manipulating the NADH-GDH isoenzyme system pave the way toward revolutionary strides in medical science. Harnessing chimerenomic medicine will lead to new generation drugs that will equip research scientists with unprecedented tools to reshape how to pursue treatment, deepen our understanding of disease, and enable a healthier future for all.

5.41 Astrocyte in Neurodenerative diseases

Special mention of the role of astrocytes in neurodegenerative diseases is necessary, astrocytes remain central in the pathogenesis of this group of diseases ranging from Alzheimer’s, Parkinson’s, Huntington’s, Amyotropic lateral sclerosis (ALS), Transmissible spongiform encephalopathy, Motor neuron disease, and Spinal muscular dystrophy. Others are Spinocerebellar ataxia, Creutzfeldt-Jakob disease, Dementia with Lewy bodies, Multiple sclerosis, Multiple system atrophy, Childhood dementia, Friedreich ataxia, Gerstmann-Straussler-Scheinker syndrome and Synucleinopathies. One thing common with these diseases is that they arise from specific neural and or neuroglia cell that began to experience attrition and cell death in certain parts of the brain, gliosis have been implicated in many of these conditions [97,98,99,100,101]. Knowing this fully well, this study showed that cell attrition and cell death accelerated after confluency was reached (fig. 3 and fig. 4), and happened as soon as the NADH-GDH isoenzyme fingerprint pattern changes (fig. 5), a process liken to a similar hallmark seen in neurodegenerative diseases. In addition GDH isoenzyme complex, as shown from this study, potentially is capable of reprogramming the attrition pathway, a discovery that can be applicable in the treatment of these neurodegenerative diseases.

5.5 Unlocking the Secrets of Aging: The Promise of NADH-GDH and Chimerenomic-RNA recent advancements in biomedical research has unveiled a captivating biochemical phenomenon that holds the potential to revolutionize our approach to aging. The cellular and molecular basis for aging of astrocytes from published works are numerous [14,15,16,17,18,19,20] but none pinpointed the direct transition to aging of cells with a switch to specific non genetic-based phenomenon.  At the forefront of this pioneering discovery is the NADH-GDH isoenzyme whose distinct chimerenomic-RNA synthetic activity has emerged as a pivotal player in the aging process of human astrocytes. [48, 49, 80] This study’s results compel us to consider a new chapter in the biology of aging, inviting optimism for a future where the markers of old age may not be so permanent after all.

From regenerative medicine to cellular biology, the findings illustrate how NADH-GDH acts as a critical transformation agent, a biochemical exclamation that abruptly signals growth and vitality, transitioning seamlessly to the defining characteristics of aging cells. By meticulously capturing these chimerenomic-RNA that encapsulates this transition, this discovery may have stumbled upon the holy-grail in age-reversal strategies. Chimerenomic-RNA, synthesized from the purified NADH-GDH isoenzyme, appears to house the essential reprogramming codes capable of counteracting the senescence pathway of astrocytic cells.

What makes this discovery even more profound is the establishment of a fingerprint for both healthy mature human astrocytes and their aging counterparts. This reference point not only shines a light on the molecular underpinnings of astrocytic evolution but also provides a keystone for future therapies aimed at mitigating aging-related declines.

Though the journey toward fully understanding the implications of reprogramming aging astrocytes just began, the potential is exhilarating. With further research on NADH-GDH isoenzyme complex and its’ chimerenomic-RNA, we may one day harness these molecular blueprints not only to halt the inexorable march of aging but to radically restore functionality to aged individuals. The curtain remains drawn on a timeline to be revealed in forthcoming clinical trials—trials that could verify whether cellular rejuvenation emerges as a tangible remedy against the multifaceted deterioration often associated with advanced age.

As we stand on the precipice of possibilities, one thing is crystal clear: that these groundbreaking methodologies arising from this study with astrocytes NADH-GDH's ambitious role will equip next generation scientists and physicians with powerful tools to drastically slow down aging's inevitable impact, thus redefining what it means to grow old in this brave new world of bioresearch. The invocation of youthful vigor may be closer than we think, igniting hope for a future rife with the vibrancy of life—regardless of the numbers racked up on our calendars.

5.6 Chimerenomic Medicine: Pioneering the Treatment and Reversal of Drug Addiction: In the ever-evolving realm of medical science, few frontiers are as promising as the study of chimerenomic medicine, especially in the battle against drug addiction. This burgeoning field holds the potential to reshape our understanding and treatment of one of society's most pressing challenges. Recent findings highlight the mechanism through which addictive substances manipulate cellular metabolism, drawing profound parallels between human cells and plant cells — insights championed by research scientists like Osuji et al., whose extensive publications over the years have illuminated this intricate relationship [48,49,50,80].

Crucially, these studies have highlighted the significant role of GDH isoenzyme, tying together the effects of phytochemicals such as opioids on both plant and human cells. This research reveals that, at a molecular level, the NADH-GDH isoenzyme plays a central role — not merely within plant biochemistry, but also within the growth and metabolism of human astrocytes, the brain's supportive cells. The parallels drawn between these systems open doors to new strategies for addressing addiction. When astrocyte cells or any cell of that matter are exposed to addictive substances, these substances cause a shift in NADH-GDH hexameric isoenzyme activities (observed in the changes in the GDH fingerprints on western blots), GDH in turn reprograms the cells’ metabolism to ensure survival of the cell through chimerenomic-RNA, and this in turn modulates various mRNAs. [48,49,50,80]

In a groundbreaking application of these principles, this study has demonstrated how the NADH-GDH isoenzyme fingerprint correlates with mature astrocyte function, and how this leads to synthesis of chimerenomic-RNA. This tectonic discovery serves as a key that can unlock the door for reprogramming addicted astrocytic cells, and reintegrating them back to their original, healthy physiological states. The implications of this research are far-reaching; by utilizing chimerenomic techniques, scientists now possess the tools to potentially reverse the pernicious effects of addiction at a cellular level. The manipulation of GDH isoenzyme activity could lead to innovative therapies that not only treat the symptoms of addiction but address its root causes by restoring normal cellular function.

Because astrocytes are involved in all aspects of addiction, including alcohol [102], cocaine [103], opioids, benzodiazepines, barbiturates, gabapentinoids, psychostimulants and more, [104, 105, 106, 107, 108] this study on astrocyte cell reprogramming stands as the foundation for the cure of addiction at cellular and molecular levels. Published works referred to here have all implicated dopamine-glutamine-gamma amino butyric acid (GABA) signaling in addiction, especially in the nucleus accumbens, [108] and astrocytes are central in all these signaling. That NADH-GDH isoenzyme is the final modulator, reprogramming and writing new codes for the total effect of these signals on the cell is clear from this study. [48,49]

As this field continues to expand, it stands on the precipice of revolutionizing addiction treatment approaches. No longer are remedies simply compelled to treat the aftermath of substance abuse; we are developing methodologies to intervene in the very processes that facilitate addiction in the first place. As chimerenomic medicine moves forward, the dream of a world devoid of addiction could very well become a reality, paving the way for healthier societies free from the shackles of drug dependence. The horizon beckons with promise and possibility — a testament to the power of chimerenomic science in the continuous quest for therapeutic innovation.

   

6.0 CONCLUSION

In a captivating study poised at the intersection of life sciences and medicine, research unveiled a remarkable transformation at the cellular level: human astrocyte cells, once mature and robust, exhibit metamorphosis into aging cells, orchestrated by the enigmatic actions of the NADH-GDH hexameric isoenzyme complex. This groundbreaking discovery shines a spotlight on metabolic intricacies previously hidden in the shadows of cellular aging.

As depicted in the electron micrograph images, the cellular architecture visibly morphs as these astrocytes transition from vitality to senescence. This research illustrated the striking structural nuances emerging during this process, and provided a hauntingly beautiful representation of the NADH-GDH hexameric isoenzyme fingerprint—a unique identifier that verifies its critical role in mediating this profound transformation.

Through its intricate reprogramming of cell growth and metabolism, the NADH-GDH hexameric isoenzyme and its’ chimerenomic RNA stand as a sentinel in the vast landscape of cellular aging. It is predicted that harnessing its regulatory potential could unlock a wealth of therapeutic possibilities, portending a significant revolution in the fields of neuroscience, neurology, medicine and beyond, and ushering in the next generation of drugs and therapies.

Such insights not only deepen our understanding of aging at the cellular level but may also hold the key to unveiling solutions for a myriad of human afflictions, many of which remain obstinately inexplicable. By elucidating the mechanisms of this cellular metamorphosis, science inches closer to weaving a narrative of hope—potentially translating these findings into actionable interventions to mitigate the implications of aging and disease.

In this delicate flux between maturity and decline, the NADH-GDH hexameric isoenzyme and its’ chimerenomic RNA emerges as both a tool for aging reversal and a beacon for future research, guiding scientists toward uncharted territories in the quest to understand and combat the challenges posed by human diseases. The paths illuminated by these findings offer a tantalizing glimpse into the possibilities that lie ahead for clinicians and research scientists alike, bringing to our finger tips the cure for Alzheimer’s and other neurodegenerative diseases, the cure of drug addiction, and the reversal of aging.

Appendix

 

Appendix A

New Terminologies: Chimerenomic glossary for the new terminologies in life sciences.

  1. These new terminologies in the life sciences describe the discovery of template-independent RNA processes that control the survival of cells and organisms other than genes. The building blocks of this life regulatory system are made up of a unique type of RNA that are not coded nor synthesized through the genetic code. These template-independent RNAs are called chimerenomic RNAs.
  2. Chimerenomics: Is the study of everything (NTintis, chigramming, GDH-chimmerization, chimere etc) about chimerenomic RNAs. Chimerenomics confers molecular chemistry pluripotency and totipotency to all cells and tissues. Chimerenomics are the processes by which whole organisms, cells and tissues differentiate, develop and grow by chigramming chimerenomic RNAs that interact with the changing physicochemical internal and external environmental conditions thereby reprogramming and optimizing those metabolic reactions that assure the continued survival of the organism.
  3. Chimere:  Is the minimum length of nucleotide sequence that can degrade homologous mRNA and other genetic code-based RNAs. Chimere is the active segment of NTinti.
  4. NTinti: This is the chimerenomic RNA molecule chigrammed (synthesized) by NADH-glutamate dehydrogenase hexameric redox cycle isoenzymes (GDH) in response to a specific environmental change. NTinti is also synthesized naturally in vivo during normal tissue differentiation, growth and development. Therefore, NTinti can be cell or tissue specific. One NTinti has more than one chimere.
  5. Chigramming: This is the process of synthesis of chimeres and NTintis by GDH. It is a spontaneous process. It is the conversion of the electromagnetic changes in the environmental conditions of cells, tissues, whole organisms to the nucleotide sequences of chimerenomic RNAs.
  6. GDH-Chimerization: This is the formation of chemical Schiff base of GDH isoenzymes in response to a new environment leading to new hexameric isoenzyme complexes. This is the initiation process for chigramming.
  7. Functional chimerenomics: This is the study of the biological functions of chimere and NTinti.
  8. Differential chimerenomics: This is the comparison study of the chimeres and NTintis from same or different tissues under various environmental conditions.
  9. Other terminologies

a). Clinical chimerenomics: The application of chimerenomics to clinical studies.

b). Chimerenomic Medicine: This is the application of chimerenomics to primary care in the prevention and treatment of human disorders, diseases and wellness conditions in humans.

c). Chimerenomic Chemistry

d). Chimerenomic Physiology

e). Molecular Chimerenomics

f). Chimerenomic Biology

g). Chimerenomic Pharmacology etc.

 

 

Appendix B

 

 
 

Material

Additional Information/Purpose

Manufacturer

Product ID

Astrocyte Cells

Cells for Study

iXCells Biotech

10HU-035

Astrocyte Medium

Cell Culturing and Proliferation

iXCells Biotech

MD-0039

T-75 Flask

Cell Culturing

Cellstar

658170

PBS Buffer

Cell Washing During Initial Expansion

ThermoScientific

XF35077

0.25% Trypsin/EDTA

Cell Disassociation

Gibco

2492783

0.22µm Sterilization filter unit

Filtration

Millipore, Steri-top

MP223002G2

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Appendix C

Device/Equipment

Condition

Condition Parameter

Note

Cell Culture Incubator

Temperature

37°C

 

 

Humidity

≥ 85% RH

Humidity due to water tray in incubator

 

Environment

5% CO2

 

Water Bath

Temperature

37°C

 

Biological Fridge

Temperature

4°C

 

Biological Ultra-Low Freezer

Temperature

-80°C

 

Cell Cryogenic Rack Tank

Temperature

~ -196°C

In vapor phase of liquid nitrogen

 

 

Appendix D

Formula

If y (number cells) = Ni (e^ kt) (Exponential growth or decay equation)

e^kt (exponential factor)

Then we determined that

Et^ (d-1) + {Ni*(d-1) + Ni} - e^ (Et+d-1)

e = 2.718 (Euler constant)

DT = Doubling time

N1 = number cells at Initial seed

Et = Entropy

d = Days since culture

- e^ (Et+d-1) is a Modified Decay Factor

Et^ (d-1) is the exponent of Entropy by days

{N1*(d-1) + N1} is the

DT = T Ln2 / Ln (n10/n1)

Decay and Attrition of HAC post Confluence

The exponential equation below has been used to estimate exponential growth and decay or attrition in rapidly changing system and holds in this situation as well.

Where N (t) is the quantity at time tN0 = N (0) is the initial quantity, that is, the quantity at time t = 0

https://en.wikipedia.org/wiki/Exponential_decay

We used this equation to calculate ?, the decay constant as,

  (Where r is the Mean Lifetime)

 

 

Appendix E

Correlation coefficient (r) Calculation:

r =∑ (xi - X?) (yi - Y)√ ∑ (xi - X?)2 ∑ (yi - Y)2

∑ (xi - X)2 = 12.35045,   ∑ (yi - Y)2 = 4.6208,   ∑ (xi - X?) (yi - Y) = 7.5544

Now putting values in the above equation:

r =7.5544√(12.35045)(4.6208) => r =7.55447.5544

r =7.55447.5544 => r = 1

The value of r is 1. (A Perfect Positive and Positive Correlation)

 

 

 

Appendix F

The Population Doubling Level (PDL) was determined using the known formula below.

PDL = 3.32(Logn10 – Logn1) + Pas

Population Doubling Time (DT)

DT = T Ln2 / Ln (n10/n1)

GR (Growth Rate) = Ln (N10/N1) / T   https://encyclopedia.pub/entry/36230        

 

 

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