Improvement effect and mechanism of ethanol extract from Citri Reticulatae Pericarpium on triglyceride in hyperlipidemia model rat / 中国中药杂志

ABSTRACT

The aim of this paper was to study the improvement effect of ethanol extract from Citri Reticulatae Pericarpium(CRP) on triglyceride of hyperlipidemia model rats, and to explore the possible mechanism. SD rats were randomly divided into normal group, model group, positive control group, and high, medium and low-dose CRP ethanol extract groups, with 10 rats in each group. During the experiment, except for the normal group that was fed with distilled water and ordinary feed, rats in the other groups were given different concentrations of alcohol and fed with high-sugar and fat diets. All rats were given free diets. While being modeled, each group was administered with 0.01 mL·g~(-1) by gavage once a day for six weeks. Blood samples were collected after two weeks, four weeks and six weeks of drug treatment. After the completion of the experiment, blood, liver and adipose tissue were collected. Triglyceride(TG), alanine aminotransferase(ALT), aspartate aminotransferase(AST), alkaline phosphatase(ALP) in serum, TG in liver tissue and TG in fecal were detected. Free fatty acid(FFA) and triglyceride-related hydrolase, such as adipose tiglyceride lipase(ATGL), lipoprotein lipase(LPL), hepatic lipase(HL), hormone-sensitive triglyceride lipase(HSL) were detected by ELISA. The mRNA expressions of peroxisome proliferators-activated receptors(PPARγ), sterol regulatory element binding protein 1 c(SREBP-1 c) and farnesoid X receptor(FXR) were determined by RT-PCR. Compared with the model group, each administration group could reduce TG levels in serum and liver to varying degrees, reduce serum ALT, AST, ALP activities, significantly reduce free fatty acid content in serum, significantly increase triglyceride metabolism-related enzymes, including fat ATGL, LPL and liver HL content, and significantly reduced the content of fat HSL. According to the study of transcriptional regulation genes relating to triglyceride metabolism, extract from CRP could significantly increase the mRNA expressions of PPARγ and FXR. In conclusion, ethanol extract from CRP could ob-viously reduce the TG level of hyperlipidemia model rats, and might reduce plasma TG content by increasing PPARγ-LPL/ATGL and FXR-HL triglyceride hydrolysis pathways.