11-[beta] Hydroxysteroid dehydrogenase type 2 expression in white adipose tissue is strongly correlated with adiposity

Abstract

Glucocorticoid action within the cells is regulated by the levels of glucocorticoid receptor (GR) expression and two enzymes, 11-[beta] hydroxysteroid dehydrogenase type 1 (11 [beta]HSD1), which converts inactive to active glucocorticoids, and 11-[beta] hydroxysteroid dehydrogenase type 2 (11[beta]HSD2), which regulates the access of active glucocorticoids to the receptor by converting cortisol/corticosterone to the glucocorticoidinactive form cortisone/dehydrocorticosterone. MaleWistar rats developed obesity by being fed a high-fat diet for 56 days, and GR, 11[beta]HSD1 and 11[beta]HSD2 gene expression were compared with control-diet fed animals. Gene expression analysis of 11[beta]HSD1, 11[beta]HSD2 and GR were performed by RT-PCR in subcutaneous and retroperitoneal adipose tissue. High-fat fed animals overexpressed 11[beta]HSD2 in subcutaneous but not in retroperitoneal fat. Interestingly, mRNA levels strongly correlated in both tissues with different parameters related to obesity, such as body weight, adiposity and insulin resistance, suggesting that this gene is a reliable marker of adiposity in this rat model of obesity. Thus, 11[beta]HSD2 is expressed in adipose tissue by both adipocytes and stromal-vascular cells, which suggests that this enzyme may play an important role in preventing fat accumulation in adipose tissue.