HSP90AA1 promotes viability and lactate production but inhibits hormone secretion of porcine immature Sertoli cells.

Heat shock protein 90 (HSP90), as a molecular chaperone, regulates hundreds of protein clients under both physiological and stress conditions in eukaryotic cells. However, the functional role of HSP90 in mammalian male reproduction remains largely unknown. Here, we aimed to investigate the function and effect of HSP90AA1 on the basic and reproductive function of pig immature Sertoli cells (iSCs). We first confirmed that the transfection of pBI-CMV3-HSP90AA1 vector into porcine iSCs for 24 h significantly increased mRNA and protein levels of HSP90AA. Moreover, HSP90AA1 over-expression significantly increased cell viability and the PLK2 mRNA abundance, promoted lactate production via elevating the LDHA activity, and inhibited the secretion of anti-Mullerian hormone and estradiol. In comparison, HSP90AA inhibition by allylamino-17-demethoxygeldanamycin (17-AAG) (2 µM) treatment of pig iSCs for 36 h had a totally contrasting effect, i.e. significantly reduced cell viability, promoted cell apoptosis via modulating expression of genes related to cell cycle and apoptosis (CCNB1, CCN1, PLK2, PTMA, YBX3 and CASP3), suppressed lactate production via dropping LDHA activity, but increased the secretion of anti-Mullerian hormone and estradiol. Taken together, our findings demonstrated that HSP90AA1 could regulate positively cell viability and lactate production, but negatively the secretion of reproductive hormones (anti-Mullerian hormone and estradiol). However, the detailed molecular mechanism of HSP90AA1 remains to be investigated.