Leucine and skeletal muscle disuse: clinical anti-atrophic efficacy and related mechanisms

Abstract

The reversion/atenuation of skeletal muscle atrophy is an important framework to be investigated in several conditions able to induce it, such as immobilization-induced skeletal muscle disuse. Although skeletal muscle disuse phenomenon is widely studied, there is a lack of well controlled nutritional studies in current literature that assist the development of potential anti-atrophic strategies. This study aims to evaluate the effect of leucine supplementation isolated or combined (BCAA) on immobilization-induced (knee brace) skeletal muscle atrophy due to surgical reconstruction of anterior cruciate ligament (ACL). Male and physically active adult subjects will be randomized into 3 groups: leucine, BCAA or placebo supplementation. Both groups will be composed by subjects who underwent the procedure of ACL reconstruction. Supplementation protocol will start from 10 days prior knee surgery to 7 days after it without exercise or active rehabilitation protocol. We intend to verify the effectiveness of leucine supplementation on structure and function of quadriceps muscle and, furthermore, the possible cellular mechanisms involved in muscle remodeling and modulated by these interventions in order to propose a possible nutritional anti-atrophic strategy. (AU)