Epigallocatechin‐3‐gallate increases the expression and secretion of adiponectin protein in 3T3‐L1 adipocytes

Abstract

(−)‐Epigallocatechin‐3‐gallate (EGCg) has been shown to play a role in the improvement of glucose metabolism and insulin sensitivity in both diabetic and hypertensive rats. Adiponectin is an insulin‐sensitizing hormone secreted almost exclusively from mature adipocytes, which improves glucose uptake by tissues. We hypothesized that the improvement in insulin sensitivity in EGCg‐fed animals may be a result of changes in adiponectin expression. The objective of this study was to measure adiptonectin levels in EGCg treated 3T3‐L1 cells after their differentiation into mature adipocytes. Mature 3T3‐L1 adipocytes were incubated with 5μM EGCg or vehicle for 24h. EGCg increased intracellular accumulation of adiponectin, which was demonstrated by Western blot analysis. In addition, an increase in the secretion of adiponectin by adipocytes into culture media was detected by ELISA. These results show that a physiologically relevant concentration of EGCg can influence the expression of adiponectin, and suggest a mechanism by which EGCg can modify glucose metabolism. Supported by FAES