Role of estrogen-related receptor α in adipocyes lipolysis

Abstract:

Estrogen-related receptor α (ERRα) is a key regulator for energy metabolism and adipogenesis. However, its role in lipolysis is unknown. To study the function of ERRα in lipolysis, primary cultured differentiated porcine adipocytes were treated by a specific inverse agonist XCT790 or infected with adenoviral vector expressed ERRα for 48 h, in the absence and/or presence of specific protein kinase A (PKA) inhibitor or extracellular signal-related kinase (ERK) inhibitor. Then, we measured the triglyceride (TG) content and the glycerol release into the culture media to analysis the effect of ERRα on lipolysis; Further, we analyzed the expression of PPARγ, perilipin A, p-perilipin A, HSL and ATGL with Western blotting. Here, we found that ERRα significantly increased adipocytes differentiation, TG accumulation and glycerol release. Separately or simultaneously block the PKA and ERK pathway do not significantly altered the effect of ERRα on glycerol release. ERRα significantly up-regulated the proteins expression of PPARγ, perilipin A, HSL and ATGL, while the p-perilipin A protein level was not significantly changed. These findings imply that ERRα could increase lipolysis via up-regulating HSL and ATGL, thereby to supply more FFA as substrate for a larger turnover of cellular triglyceride pool during adipocytes differentiation.