Hypoxia– and exercise-mediated effects on the muscle mass via endogenous local progenitors and the hippo signaling pathway

Hypoxia is the state of lowered O2 tension condition that influence skeletal muscle mass when associated to resistance exercise whether after acute or chronic exposure. The effects of hypoxia on muscle mass are largely investigated but the regulatory mechanisms remain blurring. Aiming to investigate these mechanisms and the possible contribution of Hippo pathway in both protein turnover and satellite cells regulation, we exposed young healthy subjects to acute hypoxia coupled to resistance exercise. Skeletal muscle protein synthesis was blunted by hypoxia and differentiation genes were upregulated while Hippo pathway remained unaffected. Moreover, skeletal muscle machinery genes were regulated by hypoxia suggesting structural adaptations. Surprisingly, a four-week training in hypoxic condition failed to induce those adaptations. This topic requires further investigation to highlight the precise mechanisms and adaptations induced by hypoxia in sport.