Physiology of Aging: Mechanisms, Adaptations, and Interventions

Abstract

The current research aimed to review in detail the physiological processes that accompany biological ageing, organ-level responses, and manipulative approaches to address age-associated deterioration. Ageing is a process characterised by reduced physiological integrity, compromised function, and increased susceptibility to chronic diseases. The rate of the world population ageing is unprecedented, and it is estimated that by 2050, the number of people aged 60 and above will reach about 2.1 billion. Biological ageing is defined as cumulative damage of molecules and cells with time. The hallmarks of ageing framework recognises nine conserved mechanisms: genomic instability, telomere loss, epigenetic changes, maintenance of proteostasis, deregulated nutrient sensing, mitochondrial dysfunction, cellular senescence, stem cell exhaustion, and altered intercellular communication. At the organ level, there are cardiovascular stiffness, sarcopenia, endocrine dysregulation, immunosenescence, and neurodegeneration. Such interventions include lifestyle changes, pharmacological treatments with metformin and rapamycin, and new biotechnological treatments such as partial cellular reprogramming. Metformin and rapamycin have the potential to slow the progression of age-related diseases in experimental animals, and senolytic agents have potential in preclinical research. Recent technologies that employ Yamanaka factor-based reprogramming have shown impressive lifespan extension of aged mice. The issues of clinical translation are also fraught with safety, ethical, and proper trial design concerns. Epigenetic clocks and frailty indices are currently under development as biomarkers of ageing. The future lines of research focus on making geroscience methods more individualised and ensuring the intervention using the approach is both safe and effective for human use.