人参皂苷 Rg1对大鼠非酒精性脂肪性肝病和肠道菌群影响的研究

Effect of ginsenoside Rg1 on non-alcoholic fatty liver disease and intestinal microbiota in rats

摘要:

目的 探讨人参皂苷Rg1对大鼠非酒精性脂肪性肝病（non-alcoholic fatty liver disease，NAFLD）的改善情况及对肠道菌群的潜在影响。方法 将24只大鼠随机分为对照组、高脂高糖（high-fat and high-sugar，HFHS）组、人参皂苷Rg1低剂量治疗组、人参皂苷Rg1高剂量治疗组。采用HFHS饮食喂养制备大鼠NAFLD模型，给予人参皂苷Rg1灌胃干预治疗4周。麻醉处死大鼠，测量各组大鼠的体质量和肝重，计算肝重/体质量的比值；采用酶联免疫吸附实验（enzyme-linked immunosorbent assay，ELISA）分别检测各组大鼠血清总胆固醇（total cholesterol，TC）、甘油三酯（triglyceride，TG）、丙氨酸转氨酶（alanine aminotransferase，ALT）、天冬氨酸转氨酶（aspartate aminotransferase，AST）、低密度脂蛋白胆固醇（low density lipoprotein cholesterol，LDL-C）、高密度脂蛋白胆固醇（high density lipoprotein cholesterol，HDL-C）、谷胱甘肽过氧化物酶（glutathione peroxidase，GSH-px）、超氧化物歧化酶（superoxide dismutase，SOD）及丙二醛（malondialdehyde，MDA）的含量变化；采用苏木精-伊红（hematoxylin eosin，HE）染色法观察各实验组肝脏脂肪变性情况；采用16S rRNA基因高通量测序检测各组大鼠肠道微生物改变情况。结果 人参皂苷 Rg1干预治疗可降低NAFLD大鼠的体质量（P<0.01）和肝重（P<0.05）；HE染色结果显示，人参皂苷 Rg1干预治疗可有效减轻NAFLD大鼠肝脏的脂肪变性（P<0.05）；ELISA检测结果显示，人参皂苷Rg1干预治疗可降低NAFLD大鼠血清TG、TC、ALT、AST、LDL-C、MDA等指标的表达（P<0.05），HDL-C、GSH-px等指标在人参皂苷Rg1干预治疗后表达显著升高（P<0.05）；肠道微生物α多样性分析结果显示，给予高剂量人参皂苷Rg1干预治疗可增加NAFLD大鼠肠道微生物α多样性（P<0.05）；β多样性结果显示，给予人参皂苷Rg1干预治疗可显著改变NAFLD大鼠肠道微生物组成（P<0.01）；线性判别分析结果显示，高剂量人参皂苷Rg1干预治疗后，其肠道微生物中的优势物种为毛螺菌属、双歧杆菌属、拟杆菌属、厌氧螺旋菌属等肠道益生菌。结论 人参皂苷 Rg1干预治疗可减轻NAFLD大鼠肝脂肪病变和氧化应激反应，其作用机制可能与Rg1改善NAFLD大鼠肠道微生物结构和多样性，以及增加肠道益生菌的丰度有关。

Abstract:

Objective To investigate the positive effects of ginsenoside Rg1 on non-alcoholic fatty liver disease（NAFLD） and regulation of the intestinal microbiota.Methods The 24 SD rats were randomly divided into the control group，high-fat and high-sugar （HFHS） group， ginsenoside Rg1 low dose treatment group，and ginsenoside Rg1 high dose treatment group. The NAFLD model rats were fed with HFHS diet. After 4 weeks’ treatment of ginsenoside Rg1，the rats were sacrificed under anesthesia. Then，their body weight and liver weight were measured. Meanwhile，the liver weight/body weight ratios were calculated. Enzyme-linked immunosorbent assay（ELISA） was used to detect the levels of total cholesterol（TC），triglyceride（TG），alanine aminotransferase（ALT），aspartate aminotransferase（AST），low density lipoprotein cholesterol（LDL-C），high density lipoprotein cholesterol（HDL-C），glutathione peroxidase（GSH-px），superoxide dismutase（SOD） and malondialdehyde（MDA） in peripheral blood serum. Hematoxylin eosin（HE） staining was used to observe liver steatosis. Additionally，16S rRNA gene bioinformatics analysis and statistics were conducted to detect the changes in microbial diversity of rats among the four groups.Results Ginsenoside Rg1 could reduce NAFLD-induced body weight（P<0.01） and liver weight（P<0.05）. The HE staining results showed that ginsenoside Rg1 intervention could effectively reduce liver steatosis in NAFLD rats（P<0.05）. ELISA test results showed that ginsenoside Rg1 intervention could reduce the expression of serum TG，TC，ALT，AST，LDL-C and MDA in NAFLD rats（P<0.05），while HDL-C and GSH-px were significantly increased after ginsenoside Rg1 intervention（P<0.05）. The α diversity results showed that high dosage ginsenoside Rg1 intervention could increase the community richness and community diversity of the intestinal microbiota in NAFLD rats（P<0.05）. The β diversity results showed that ginsenoside Rg1 intervention could change the structure of the intestinal microbiota in NAFLD rats（P<0.01）. The LEfSe（linear discriminant analysis effect size） analysis results showed that after high dose ginsenoside Rg1 intervention，the dominant species of intestinal microorganisms were Lachnospiraceae，Bifidobacterium，Bacteroides，Anaerobiospirillum and other intestinal probiotics.Conclusion Ginsenoside Rg1 intervention could alleviate liver fatty lesions and oxidative stress response in NAFLD rats. The pharmacological activity of ginsenoside Rg1 is probably related to the improvement of intestinal microbial structure and diversity，especially increasing the beneficial intestinal microbiota in NAFLD rats.