United States: In a significant stride towards deciphering the enigma of aging, researchers at The University of Texas MD Anderson Cancer Center have unveiled a molecule that exhibits profound potential in curbing age-induced inflammation while simultaneously invigorating cerebral and muscular functionalities in preclinical paradigms.
This groundbreaking investigation, articulated in the prestigious journal Cell, brings to light a diminutive molecular entity capable of rejuvenating telomerase reverse transcriptase (TERT) to its erstwhile youthful concentration—a factor that wanes with the advance of age. By reconstituting these pivotal TERT levels within aged experimental models, the researchers observed a marked attenuation in cellular senescence and tissue inflammation, alongside a resurgence in neurogenesis that bolstered memory capabilities. Additionally, a notable enhancement in neuromuscular efficacy was documented, translating to improved strength and motor coordination.
Crucially, the study elucidated that TERT’s influence transcends its traditional role of merely elongating telomeres. It functions as a transcriptional architect, orchestrating the expression of an array of genes that govern neurogenesis, cognitive acuity, cellular aging, and inflammatory responses, according to the reports by scitechdaily.com.
The implications of these findings, should they be corroborated in clinical settings, could be revolutionary, potentially offering therapeutic avenues for combating a spectrum of age-associated maladies, including Alzheimer’s, Parkinson’s, cardiovascular afflictions, and various oncological conditions.
Professor of Cancer Biology, MD Ronald DePinho, was quoted saying, “Epigenetic repression of TERT plays a major role in the cellular decline seen at the onset of aging by regulating genes involved in learning, memory, muscle performance, and inflammation.”
The expert further stated, “By pharmacologically restoring youthful TERT levels, we reprogrammed expression of those genes, resulting in improved cognition and muscle performance while eliminating hallmarks linked to many age-related diseases.”
Aging is intrinsically linked with a series of epigenetic alterations that contribute to the progressive decline in physiological and functional capabilities. Among the defining characteristics of aging is the gradual erosion of telomeres—protective structures at the ends of chromosomes that ensure genomic stability. This attrition is exacerbated by oxidative stress, as free radicals can inflict damage upon telomeric sequences.
When telomeres become critically shortened or compromised, they initiate a persistent DNA damage response, culminating in cellular senescence—a state in which cells secrete pro-inflammatory factors that exacerbate tissue degradation, thereby accelerating aging and increasing the risk of cancer.
Telomerase, a crucial protein complex, is responsible for the synthesis and elongation of telomeres. However, with the advance of age, its activity diminishes due to the epigenetic silencing of the TERT gene, particularly during the natural aging process or the onset of age-related diseases such as Alzheimer’s, according to scitechdaily.com.
Previous research conducted by the DePinho laboratory demonstrated that in vivo deactivation of the TERT gene precipitated premature aging, a condition that could be reversed through the reactivation of TERT. Notably, the researchers discovered that certain cell types, including neurons and cardiac cells, could be rejuvenated without the necessity for cell division, which is typically required for telomere synthesis.
These findings led to the hypothesis that TERT possesses additional functions beyond telomere synthesis and that the overall levels of telomerase play a pivotal role in the aging process. Building upon this hypothesis, the research team, spearheaded by DePinho and first author Dr. Hong Seok Shim, embarked on the development of a therapeutic agent aimed at restoring TERT levels.
Through an extensive high-throughput screening process involving over 650,000 compounds, the team identified a small molecule TERT-activating compound (TAC) capable of epigenetically de-repressing the TERT gene and reinstating the physiological expression levels observed in youthful cells.
In preclinical models representing individuals over 75 years of age, a six-month course of TAC treatment yielded remarkable results. The treatment spurred the formation of new neurons within the hippocampus—the brain’s memory hub—and enhanced cognitive performance in memory tests. Additionally, there was a notable upregulation of genes associated with learning, memory, and synaptic function, consistent with TERT’s role in modulating transcription factor complexes that regulate a wide array of genes.
TAC treatment also led to a significant reduction in inflammation—a chronic, low-grade inflammation that is a hallmark of aging and a contributor to various age-related diseases. This was evidenced by decreased inflammatory markers in both blood and tissue samples. Furthermore, TAC effectively eliminated senescent cells by repressing the p16 gene, a critical regulator of cellular senescence.
The compound also enhanced neuromuscular function, coordination, grip strength, and speed in the preclinical models, effectively reversing sarcopenia—a condition characterized by the loss of muscle mass, strength, and performance with age.
Moreover, TAC treatment in human cell lines promoted telomere synthesis while reducing DNA damage signals at telomeres, extending the proliferative capacity of these cells and demonstrating the compound’s efficacy in ex vivo human models, as per scitechdaily.com.
In this regard, DePinho further mentioned, “These preclinical results are encouraging, as TAC is easily absorbed by all tissues, including the central nervous system. Yet further studies are needed to properly assess its safety and activity in long-term treatment strategies. However, our deeper understanding of the molecular mechanisms driving the aging process has uncovered viable drug targets, allowing us to explore opportunities to intercept the causes of a variety of major age-related chronic diseases.”