Anti-Obesity Effect of Ethyl Acetate Fraction from 50% Ethanol Extract of Fermented Curcuma longa L. in 3T3-L1 Cells

摘要

In the present study, we investigated the effect of ethyl acetate fraction from 50% ethanol extract of fermented Curcuma longa L. (FCEE) on lipid metabolism in 3T3-L1 cells. The safety range of FCEE was up to 300 mug/mL. Effects of FCEE on lipid accumulation and intracellular triglyceride (TG) content in 3T3-L1 cells were examined by Oil Red O staining and AdipoRed assay. Compared to adipocytes, lipid accumulation and intracellular TG content were significantly reduced by 10.2% and 13.7%, respectively, upon FCEE treatment at a concentration of 200 mug/mL. Glucose uptake by 3T3-L1 cells was significantly reduced by 36.6%> compared to adipocytes at a concentration of 200 mug/mL. On day 8, free glycerol release into the culture medium was significantly reduced compared to adipocytes at concentrations of 50, 100, and 200 mug/mL of FCEE. FCEE significantly stimulated RNA expression of AMP-activated protein kinase (AMPK) and suppressed mRNA expressions of sterol regulatory element-binding protein-1c (SREBP-1c), CCAAT/enhancer binding proteins a (C/EBP alpha ), and peroxisome proliferator- activated receptor gamma (PPAR gamma) in 3T3-L1 cells. These results suggest that FCEE inhibits adipogenesis through activation of AMPK mRNA expressions and inhibition of SREBP-1c, C/EBP alpha , and PPAR gamma mRNA expressions.