The biphasic activity of autophagy and heat shock protein response in peripheral blood mononuclear cells following acute resistance exercise in resistance-trained males.

Abstract

Autophagy and heat shock protein (HSP) response are proteostatic systems involved in the acute and adaptive responses to exercise. These systems may upregulate sequentially following cellular stress including acute exercise, however, currently few data exist in humans. This study investigated the autophagic and HSP responses to acute intense lower body resistance exercise in peripheral blood mononuclear cells (PBMCs) with and without branched-chain amino acids (BCAA) supplementation. Twenty resistance-trained males (22.3 ± 1.5yr; 175.4 ± .7cm; 86.4 ± 15.6kg) performed a bout of intense lower body resistance exercise and markers of autophagy and HSP70 were measured immediately post- (IPE) and 2, 4, 24, 48, and 72h post-exercise. Prior to resistance exercise, 10 subjects were randomly assigned to BCAA supplementation of 0.22g/kg/d for 5days pre-exercise and up to 72h following exercise while the other 10 subjects consumed a placebo (PLCB). There were no difference in autophagy markers or HSP70 expression between BCAA and PLCB groups. LC3II protein expression was significantly lower 2 and 4h post-exercise compared to pre-exercise. LC3II: I ratio was not different at any time point compared to pre-exercise. Protein expression of p62 was lower IPE, 2, and 4h post-exercise and elevated 24h post-exercise. HSP70 expression was elevated 48 and 72h post-exercise. Autophagy and HSP70 are upregulated in PBMCs following intense resistance exercise with autophagy increasing initially post-exercise and HSP response in the latter period. Moreover, BCAA supplementation did not affect this response.