Stress-conditioned small extracellular vesicles from young cells to restore resilience in aging

Aging is characterized by a progressive decline in cellular stress responses, including oxidative stress resistance, mitochondrial quality control, DNA repair, and autophagy. Small extracellular vesicles (sEVs) released by all cell types are now recognized as key mediators of intercellular communication, particularly under stress conditions. sEVs derived from cells exposed to controlled, non-lethal stressors (e.g., hypoxia, oxidative, mitochondrial, or genotoxic stress) can carry protective molecules that promote stress adaptation and repair in recipient cells. We propose that stress-conditioned sEVs from young cells can restore adaptive stress responses and repair capacity in aging tissues by delivering molecular mediators that are diminished or dysregulated in aged cells. This concept builds on three well-established principles: (1) the content of sEVs reflects the physiological or stress state of the donor cell; (2) sEVs released from stressed cells convey adaptive mediators that promote resilience and repair in recipient cells; and (3) both stress-adaptive responses and intercellular communication are altered in the elderly. This hypothesis proposes that sEVs released by stress-conditioned young cells could constitute a novel gerotherapeutic approach capable of restoring adaptive stress responses and exerting beneficial effects on multiple hallmarks of aging in aged organisms. We discuss the biological rationale, supporting evidence, and experimental models to test this concept.