Exercise counteracts vascular aging in long-term spaceflight: challenges and perspective

Vascular aging, characterized by vascular wall thickening, collagen deposition, arterial stiffening, and endothelial dysfunction, is not necessarily determined chronologically, but can increase faster due to physical inactivity and other health risk factors. Astronauts exposed to microgravity and radiation during spaceflight undergo physiological changes associated with decrements in metabolic regulation, insulin signaling, endothelial homeostasis, and redox balance, which may foster aging features in the vasculature. Exercise has been proved an effective approach to mitigate microgravity-induced aging changes and thus protect vascular health. We here briefly review the mechanisms contributing to vascular aging changes in microgravity and exercise-afforded vasoprotection. Deep planetary exploration and longer space travel would impose unknown health risks, therefore, better understanding of exercise-induced health effects from an integrative perspective will help develop more efficient and effective exercise countermeasures.