合生元调整肠道微生态治疗NAFLD及其对TLR4的影响

发布时间：2018-05-17 02:31

本文选题：非酒精性脂肪性肝病 + 肠道微生态　；参考：《广东药学院》2014年硕士论文

【摘要】：目的证明肠道微生态失衡是高脂饮食诱导的非酒精性脂肪性肝病（NAFLD）发生发展的一个重要途径，而合生元通过调节肠道菌群及影响TLR4的表达来改善NAFLD。方法采用高脂饮食喂养SD大鼠，构建NAFLD大鼠动物模型，分别于高脂饮食第4周末、第8周末、第12周末三个时间点给予各实验组大鼠合生元口饲两周后，取各组大鼠肝脏组织，进行HE染色，对其组织病理学改变进行评分，观察各组大鼠肝脏组织学形态的改变，并测定肝脏组织中甘油三酯（TG）、胆固醇（TC）的含量，及血清空腹血糖（GLU）、空腹胰岛素(FINS)、甘油三酯（TG）、胆固醇（TC）、天门冬氨酸氨基转移酶（AST）、丙氨酸氨基转移酶（ALT）、总胆固醇（TC）、总甘油三酯（TG）、高密度脂蛋白（HDL）、低密度脂蛋白（LDL）等的含量，应用ELISA法和免疫组化方法测定大鼠肠道粘膜Toll样受体4（TLR4）的表达水平，应用16s rRNA荧光定量PCR方法动态监测大鼠肠道主要菌群的变化情况。结果 1.高脂饮食组体重、肝指数、血清学指标TG、TC、AST、LDL、GLU、FINS水平显著高于正常饮食组（P＜0.05），自主活动次数、饮食量、饮水量均显著低于正常饮食组（P＜0.05）。经过合生元干预2周可以使高脂饮食的大鼠血清学指标TG、TC、AST、LDL、GLU、FINS水平显著降低，差异具有统计学意义（P＜0.05），ALT、HDL未见明显差异，肝指数也有所下降，但差异不具有统计学意义（P＞0.05），自主活动次数、饮食量、饮水量显著增高，差异具有统计学意义（P＜0.05）。 2.高脂饮食第4周，肝脏组织开始出现散在脂肪沉积；第8周，肝脏组织呈单纯性脂肪变样改变；第12周，肝脏组织出现了非酒精性脂肪性肝炎样改变。分别在上述三个时间点给予合生元干预2周后，肝脏组织脂肪沉积情况改善不明显，但并未发现脂肪沉积进一步恶化趋势。 3.随着实验的进程，，高脂饮食组TLR4的表达量呈逐渐增高趋势，且表达显著高于正常饮食组，差异具有统计学意义（与正常饮食组相比P＜0.05），合生元干预2周后可显著下调高脂饮食的大鼠TLR4的表达，差异具有统计学意义（与高脂饮食组相比P＜0.05）。 4.高脂饮食组大鼠从第2周开始，肠道菌群中双歧杆菌和乳酸杆菌的表达量显著下降，差异均具有统计学意义（与正常饮食组相比P＜0.05），肠球菌表达量出现显著升高，差异具有统计学意义（与正常饮食组相比P＜0.05）。经过合生元干预2周后，可使双歧杆菌和乳酸杆菌的表达显著上调，肠球菌的表达显著下调，差异均具有统计学意义（与高脂饮食组相比P＜0.05）。结论高脂饮食诱导的大鼠NAFLD模型，先出现肠道菌群紊乱，而后出现肝脏病理学改变，应用合生元调节肠道菌群后，可以下调肠道粘膜TLR4的表达，调节血清学各项指标及改善生活质量，从而达到治疗NAFLD的效果，进一步证明了高脂饮食导致的肠道菌群紊乱是NAFLD发生发展的原因之一。
[Abstract]:Purpose The results suggest that intestinal microecological imbalance is an important pathway for the development of NAFLDs induced by high fat diet, while the synbiotic elements improve NAFLD by regulating intestinal flora and influencing the expression of TLR4. Method SD rats were fed with high-fat diet to establish NAFLD rat model. The liver tissues of each group were taken out at the 4th weekend, 8th weekend and 12th week of high fat diet. The histopathological changes were evaluated by HE staining, the histopathological changes of the liver were observed, and the contents of TGG and TCC in the liver were measured. And the contents of serum fasting blood glucose (GLU), fasting insulin (FINSN), triglyceride (TGN), cholesterol triglyceride (TC), aspartate aminotransferase (AST), alanine aminotransferase (alt), total cholesterol (TC), total triglyceride (TG), high density lipoprotein (HDL), low density lipoprotein (LDL), etc. The expression of Toll like receptor 4 (TLR4) in rat intestinal mucosa was determined by ELISA method and immunohistochemical method. The changes of main intestinal flora in rats were dynamically monitored by 16s rRNA fluorescence quantitative PCR method. Result 1. The levels of body weight, liver index, and serum TGN TCX LDLU fins in high fat diet group were significantly higher than those in normal diet group (P < 0.05), and the number of independent activities, diet quantity and drinking quantity were significantly lower than those in normal diet group (P < 0.05). After two weeks of intervention, the level of serum TGG TCX ASTX GLU fins in rats with high fat diet was significantly decreased, the difference was statistically significant (P < 0.05), and the liver index was also decreased, but the difference was not statistically significant (P > 0.05), and the number of independent activities was not significant. The quantity of diet and the quantity of drinking water were significantly increased, and the difference was statistically significant (P < 0.05). 2. In the 4th week of high-fat diet, the liver tissue began to appear scattered fat deposition; at the 8th week, the liver tissue showed simple fatty variant changes; at the 12th week, the liver tissue appeared non-alcoholic fatty hepatitis like changes. At the above three time points, the fat deposition in liver tissue did not improve significantly after two weeks of treatment with synbiotic elements, but no further deterioration of fat deposition was found. 3. With the development of the experiment, the expression of TLR4 in the high-fat diet group was gradually increased, and the expression was significantly higher than that in the normal diet group. The difference was statistically significant (P < 0.05) compared with the normal diet group. The expression of TLR4 in rats with high fat diet could be significantly down-regulated after 2 weeks of intervention by combining with Shengyuan (P < 0.05) compared with that of the high-fat diet group (P < 0.05). 4. The expression of Bifidobacterium and Lactobacillus in the intestinal flora of rats in the high-fat diet group decreased significantly from the second week (P < 0.05), and the expression of Enterococcus increased significantly compared with the normal diet group (P < 0.05). The difference was statistically significant (P < 0.05). After two weeks of intervention, the expression of Bifidobacterium and Lactobacillus could be upregulated significantly, and the expression of Enterococcus was significantly down-regulated (P < 0.05 compared with the high-fat diet group). Conclusion The NAFLD model of rats induced by high-fat diet showed intestinal microflora disorder first, and then liver pathological changes. The expression of TLR4 in intestinal mucosa could be down-regulated by using synbiotic elements to regulate intestinal microflora. To regulate the serological indexes and improve the quality of life, so as to achieve the effect of treatment of NAFLD, which further proves that the intestinal flora disorder caused by high-fat diet is one of the reasons for the occurrence and development of NAFLD.
【学位授予单位】：广东药学院
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：R575.5

【共引文献】