Resveratrol inhibits 11β-hydroxysteroid dehydrogenase type 1 activity in rat adipose microsomes

It has been suggested that resveratrol, a polyphenol in wine, can regulate adiposity because it decreases adipose deposition in mice and rats; however, the mechanism underlying this effect has not been fully clarified. In humans and rodents, 11 beta-hydroxysteroid dehydrogenase type 1 (11 beta-HSD1) is expressed in liver and adipose tissue. 11 beta-HSD1 converts inactive glucocorticoid into active glucocorticoid in adipocytes. Activated glucocorticoid plays an important role in the pathogenesis of central obesity. The objective of this study was to investigate the effects of resveratrol on 11 beta-HSD1 activity in rodent adipose tissue. 11 beta-HSD1 activity in microsomes from rat mesenteric adipose depots and 3T3-L1 adipocytes was determined in the presence of 11-dehydrocorticosterone with or without varying concentrations of resveratrol. Significant inhibition of 11 beta-HSD1 by resveratrol was observed in rat adipose microsomes and 3T3-L1 adipocytes within 10 min. Time-and dose-dependent effects were also observed. The 11 beta-HSD1 activity by resveratrol was also inhibited in rat epididymal adipose tissue, and this inhibition was not recovered by estrogen receptor blockers. The kinetic study revealed that resveratrol acted as a non-competitive inhibitor of 11 beta-HSD1. K-i and IC50 values of resveratrol were 39.6 and 35.2 mu M respectively. Further, resveratrol did not affect the activities of 11 beta-HSD2 and hexose-6-phosphate dehydrogenase. These results suggest that the most likely mechanism of 11 beta-HSD1 inhibition by resveratrol is via interaction between resveratrol and 11 beta-HSD1 enzyme, rather than via a transcriptional pathway. We demonstrated that the antiobesity effects of resveratrol may partially be attributed to the inhibition of 11 beta-HSD1 activity in adipocytes.