Effects of chrysophanol on expression of SREBPs and lipid metabolism in Huh-7 cells]

Rhubarb is a traditional Chinese medicines which possess laxative, lipid-lowering, and weight-loss activities, but the active compounds of lipid-lowering and underlying molecular mechanisms are not yet clear. This study aims to explore the effects of chrysophanol on the mRNA expressions of sterol regulatory element-binding proteins (SREBPs) and lipid metabolism in human liver carcinoma Huh-7 cells, which is one of the active compounds obtained from Rhubarb. A reporter gene assay was used to test the transcription of SREBP. The intracellular triglyceride and total cholesterol contents were measured by using commercially available test kits. The SREBPs target genes expressions were measured by Quantitative Real-Time PCR. Cell viability was evaluated by Cell Counting Kit-8. As the results shown, chrysophanol (40 μmol · L(-1), 16 h) could notably inhibited human SRE promoter activity in a dose-dependent manner and decrease intracellular cholesterol and triglyceride levels. Furthermore, the mRNA expressions of SREBPs target genes were significantly downregulated by chrysophanol treatment. However there are no significant differences on cell viability when compared with the control group. These results suggested that chrysophanol might improve lipid metabolism through suppressing the mRNA expressions of SREBPs target genes to attenuate intracellular lipid accumulation.