Biochemical Basis of Aging

Introduction

As humans age, they experience a decline in physical and cognitive functions, leading to an increased risk of various age-related diseases. The biochemical basis of aging has been a topic of much research in recent years, as scientists seek to understand the underlying mechanisms that contribute to the aging process.

DNA Damage and Repair

One of the key factors in aging is the accumulation of DNA damage over time. DNA is constantly exposed to factors that can cause damage, such as UV radiation, toxins, and oxidative stress. As DNA damage accumulates, it can lead to mutations and genomic instability, which in turn can contribute to cellular dysfunction and aging. Cells have mechanisms in place to repair damaged DNA, but these repair processes become less efficient with age, leading to a buildup of unrepaired DNA damage.

Oxidative Stress and Mitochondrial Dysfunction

Oxidative stress is another major contributor to aging. Reactive oxygen species (ROS) are generated as byproducts of normal cellular metabolism, and can cause damage to cellular components such as proteins, lipids, and DNA. Mitochondria are particularly susceptible to oxidative damage, as they are the primary producers of ROS. Over time, this oxidative damage can lead to mitochondrial dysfunction, which in turn can contribute to cellular senescence and aging.

Telomere Shortening

Telomeres are protective caps at the ends of chromosomes that help maintain genomic stability. Each time a cell divides, telomeres shorten, eventually reaching a critical length that triggers cellular senescence or apoptosis. Telomere shortening is considered a hallmark of aging, as it limits the number of times a cell can divide and contributes to the decline in tissue function with age. Strategies to prevent or reverse telomere shortening are a major focus of anti-aging research.

Inflammation and Immune Dysfunction

Chronic inflammation is another key driver of aging. As we age, our immune system becomes less efficient at clearing infections and maintaining tissue homeostasis, leading to a state of chronic low-grade inflammation known as «inflammaging.» This chronic inflammation can contribute to the development of age-related diseases such as cardiovascular disease, cancer, and neurodegenerative disorders. Understanding the role of inflammation and immune dysfunction in aging is crucial for developing interventions to promote healthy aging.