Estrogen related receptor α-induced adipogenesis is PGC-1β-dependent

Previous report showed that Estrogen related receptor alpha (ERR alpha) knockout mice had a significant reduction in adipose tissue deposition. Although it was reported that ERR alpha could promote adipogenesis in several immortalized preadipocytes cell lines, the mechanism behind which is still unclear to date. Besides, the expression pattern of ERR alpha in white adipose tissue is rarely examined. Here, we show that the expression of ERR alpha in primary cultured adipocytes is closely associated with adipogenesis. Besides, we found that peroxisome proliferator-activated receptor-gamma coactivator 1 beta (PGC-1 beta) play an important role in regulating ERR alpha-induced adipogenesis. ERR alpha-induced adipogenesis was greatly attenuated when knocking down PGC-1 beta expression, while rescued by overexpression of PGC-1 beta. However, PGC-1 beta could still promote adipogenesis when suppressing ERR alpha expression. Furthermore, we demonstrated that ERR alpha could transcriptionally active PGC-1 beta expression and then enhance the formation of sterol-regulatory-element-binding protein-1c (SREBP-1c)/PGC-1 beta complex and peroxisome proliferator-activated receptor-gamma (PPAR gamma)/PGC-1 beta complex. Taken together, these results indicate that ERR alpha-induced adipogenesis is triggered by modulating the expression of PGC-1 beta.