Rhein Reduces Fat Weight indb/dbMouse and Prevents Diet-Induced Obesity in C57Bl/6 Mouse through the Inhibition of PPARγSignaling

Abstract

Rheum palmatumhas been used most frequently in the weight-reducing formulae in traditional Chinese medicine. However, the components ofRheum palmatumthat play the antiobesity role are still uncertain. Here, we tested the weight-reducing effect of two majorRheum palmatumcompounds ondb/dbmouse. We found that rhein (100 mg kg−1 day−1), but not emodin, reduced the fat weight indb/dbmouse. Using diet-induced obese (DIO) C57BL/6 mice, we identified that rhein blocked high-fat diet-induced obesity, decreased fat mass and the size of white and brown adipocytes, and lowered serum cholesterol, LDL cholesterol, and fasting blood glucose levels in the mice. To elucidate the underlying mechanisms, we used reporter assay and gene expression analysis and found that rhein inhibited peroxisome proliferator-activated receptorγ(PPARγ) transactivity and the expression of its target genes, suggesting that rhein may act as a PPARγantagonist. Our data indicate that rhein may be a promising choice for antiobesity therapy.