How and why we age

Area of Science:

• Gerontology
• Evolutionary Biology
• Cell Biology

Background:

• Natural selection prioritizes reproductive success, not indefinite longevity.
• Aging arises from the failure of biological mechanisms to maintain youthful states, not from a genetic program.
• Evolutionary pressures diminish after reproductive maturity, leading to incidental aging.

Purpose of the Study:

• To distinguish aging from disease and clarify the fundamental biology of aging.
• To investigate the cellular basis of increased vulnerability to pathology in older individuals.
• To challenge the notion that aging is solely caused by extracellular factors.

Main Methods:

• Comparative analysis of aging across species and in feral animals.
• Distinguishing age-related changes from pathological changes based on specific criteria.
• Reviewing historical and recent findings on cellular division limits and telomere dynamics.

Main Results:

• Aging is a universal biological process, distinct from disease, affecting all species over time.
• Cellular aging is an intracellular event, linked to limited cell division and telomere shortening.
• Normal cells have finite replicative capacity, while cancer cells achieve immortality through telomerase.

Conclusions:

• Aging is an inevitable consequence of evolutionary trade-offs, not a programmed disease.
• Understanding cellular vulnerability is crucial for advancing biogerontology and addressing age-associated diseases.
• The discovery of telomerase's role in cellular immortality offers insights into aging mechanisms.