Abstract
This study aimed to investigate the anti-obesity effects of Coptis chinensis (CC), BALASAN (combinational guava leaf extract and mulberry leaf extract), and CC/BALASAN (CC/BAL) on high-fat diet-induced obese C57BL/6 mice and to explore possible mediating mechanisms in 3T3-L1 pre-adipocytes. Oil red-O stain was used to test the effects of CC, BALASAN, and CC/BAL on the differentiation of 3T3-L1 pre-adipocytes. Additionally, real-time PCR was used to detect the expression of genes involved in adipocyte differentiation and inflammation-related genes in adipose tissue of mice that were fed a high-fat diet. CC, BALASAN, and CC/BAL inhibited the differentiation of 3T3-L1 pre-adipocytes and exhibited excellent inhibitory ability against the expression of PPARγ and RXRα genes associated with adipocyte differentiation. Replenishing mice with a high-fat diet with CC, BALASAN, and CC/BAL reduced body weight gaining and blood glucose and plasma cholesterol levels. CC also effectively reduced liver weight, whereas BALASAN and CC/BAL had no inhibitory effect. In addition, CC effectively inhibited the expression of C/EBP-α in adipose tissue. Interestingly, BALASAN not only inhibited the expression of C/EBP-α, but also that of PPARγ, RXRα, and TNFα. Such data indicated that CC, BALASAN, and CC/BAL may have potentially beneficial effects against obesity and associated metabolic disorders by down-regulating the PPARγ/RXRα pathway.