Peroxisomes in Aging: Guardians of Cellular Resilience and Function.

Peroxisomes are multifunctional organelles that play essential roles in lipid metabolism, redox regulation, and cellular signaling. An expanding body of evidence implicates peroxisomal dysfunction as a key contributor to aging and age-related diseases. Aging is accompanied by progressive declines in key peroxisomal functions, including catalase activity, fatty acid β-oxidation, plasmalogen biosynthesis, and the metabolism of bile acids and docosahexaenoic acid, resulting in increased oxidative stress, lipid dysregulation, and alterations in membrane composition. Impaired pexophagy further exacerbates these defects by allowing the accumulation of damaged peroxisomes and compromising cellular homeostasis. Through extensive metabolic and signaling crosstalk with mitochondria, the endoplasmic reticulum, and lysosomes, peroxisomal dysfunction can propagate oxidative and metabolic disturbances throughout the cell. In addition, peroxisome-derived signaling molecules, such as hydrogen peroxide and bioactive lipids, link peroxisomal activity to cellular stress responses and organismal metabolic homeostasis. We propose that aging-associated impairments in peroxisomal protein import, redox regulation, and selective turnover progressively shift peroxisomes from adaptive metabolic signaling hubs toward sources of chronic oxidative and lipid stress. In this context, current studies highlight peroxisomal homeostasis as a potential determinant of healthy aging and point to peroxisomal pathways as emerging targets for intervention in age-related disease.