Oxidative stress and aging

Abstract

Oxidative stress results from an imbalance between reactive oxygen species and reactive nitrogen species production and the body’s antioxidant defense mechanisms. Excessive accumulation of these reactive molecules damages lipids, proteins, and DNA, contributing to cellular dysfunction and aging. The Free Radical Theory of Aging, proposed by Denham Harman, suggests that oxidative stress accelerates molecular deterioration, leading to age-related functional decline. However, modern research highlights a nuanced perspective where oxidative stress plays both detrimental and adaptive roles, influencing cellular signaling and stress responses. Emerging evidence underscores the interplay of genetic and environmental factors in oxidative homeostasis, offering insights into potential therapeutic interventions for aging-related disorders. Understanding oxidative stress as a dynamic and regulated process rather than a purely degenerative force opens avenues for targeted strategies to modulate aging and extend healthspan. © 2026 Elsevier Inc. All rights reserved..