An mTOR paradox in sarcopenia via BCAA catabolism

Abstract

Dietary proteins stimulate skeletal muscle growth via mTOR-mediated activation of muscle protein synthesis by amino acids. Zuo and colleagues identify impaired mitochondrial branched-chain amino acid (BCAA) catabolism during sarcopenia. Pathological BCAA accumulation in aged muscle overactivates mTOR and paradoxically contributes to loss of muscle mass and strength by inhibiting autophagy and mitochondrial function.