Intro – Aging refers to the natural and gradual process of changes that occur in living organisms over time, leading to a decline in their physical, physiological, and often cognitive functions. It is a complex and multifaceted phenomenon that affects all living beings, including humans. Aging involves a combination of genetic, environmental, and lifestyle factors.
Causes
- Genetic Factors: Genetic makeup plays a significant role in determining how individuals age. Certain genes are associated with longevity and the rate of aging. Genetic mutations and variations can influence cellular processes, repair mechanisms, and overall susceptibility to age-related diseases.
- Cellular Damage and Accumulated Changes: Over time, cells accumulate damage from various sources, including environmental factors like ultraviolet (UV) radiation, pollution, and toxins. This damage can lead to DNA mutations, protein misfiling, and impaired cellular function.
- Telomere Shortening: Telomeres are protective caps at the ends of chromosomes that shorten with each cell division. Eventually, when telomeres become critically short, cells may stop dividing or enter a state of senescence (inactive state), leading to tissue dysfunction and aging.
- Oxidative Stress: This occurs when there is an imbalance between reactive oxygen species (ROS) and the body’s antioxidant defences. Oxidative stress can damage cells, proteins, lipids, and DNA, contributing to aging and age-related diseases.