P-151 - A single bout of endurance exercise induces αB-crystallin (CRYAB) modulation in cardiac muscle as it happens in oxidative skeletal muscle fibers

Abstract

CRYAB is a small Heat Shock Protein, expressed in various tissues such as skeletal and cardiac muscles, activated as phosphorylated CRYAB (pCRYAB) and involved in several pathophysiological processes. In mammals there are no reports to date on CRYAB activation following an acute endurance exercise, so the aim of my study was to explore in mouse cardiac tissue the pCRYAB levels as effect of this exercise at 0’, 15’ and 120’ of recovery. H2O2 - treated HL-1 cardiomyocytes have been utilized as in vitro model to identify the underlying molecular mechanism/s. Both in vivo and in vitro models showed no changes in CRYAB protein expression level but its phosphorylation state was significantly increased at short time, paralleled by oxidative stress markers’ modulation (i.e. 4-HNE), indicating a correlation between CRYAB activation and redox perturbation. Our previous results in skeletal muscles where exercise modulated CRYAB only in oxidative fiber types supported these data. All together these results suggest a role for CRYAB in the defense system against ROS production. Further experiments are in progress to study the possible interactors, the cellular localization and the eventual release of CRYAB in extracellular vesicles as a mean for a cross talk between tissues