Heat shock modulates adipokines expression in 3T3-L1 adipocytes

Abstract

Studies have demonstrated that heat shock is associated with alteration in energy metabolism. In this study, we investigated the effect of heat shock on gene expression and secretion of adiponectin and leptin, and gene expression of Hspa2 and Pparg in 3T3-L1 adipocytes. Compared with 37 8C, adiponectin mRNA was higher at 39 8C, and lower at 41 8C. Leptin mRNA was higher when adipocytes were exposed to 41 8C compared with 37 and 39 8C. Secretion of adiponectin increased at 39 8C, and when cells were exposed to 41 8C it was not detectable. Leptin secretion increased significantly at 41 8C, compared with 37 and 39 8C. Hspa2 mRNA was increased at 39 8C, and the highest level was reached at 41 8C. Pparg mRNA exhibited a substantial increase in a temperature-dependent manner. The study provides the first evidence of a possible direct effect of heat shock on adiponectin and leptin gene expression and secretion, and demonstrates that the expression of the two adipokines is differentially regulated at the temperatures tested.