高脂饮食诱发小鼠肥胖及其对肠道菌群结构影响的研究

Effects of High Fat Diet on Mouse Obesity and Its Effect on Intestinal Microflora Structure

目的探讨高脂饮食对小鼠体重、血脂以及肠道菌群结构的影响。方法将20只C57BL/6J雌性小鼠随机分为正常对照组(10只)和高脂饮食组(10只),分别给予普通饮食和高脂饮食。饲喂12周后,称量小鼠体重,测定小鼠血清总胆固醇(TC)、甘油三脂(TG)、高密度脂蛋白胆固醇(HDL-C)、低密度脂蛋白胆固醇(LDL-C)的含量。采集小鼠粪便,提取细菌总DNA,PCR扩增获得16S r DNA基因V4标签片段,用于Hi Seq 2500高通量测序,基于QIIME平台比较小肠内容物菌群结构多样性。结果高脂饮食组小鼠体重及血清TC、TG、HDL-C、LDL-C均显著高于正常对照组。正常对照组小鼠粪便菌群多样性高于高脂饮食的小鼠。高脂饮食组小鼠的粪便中含有的厚壁菌较正常组显著升高,但是拟杆菌门数量显著低于正常对照组。结论高脂饮食能诱导小鼠肥胖,改变小鼠肠道菌群结构。

Objective The effects of high fat diet on the body weight, the levels of serum lipid and the structure of intestinal flora of mice were discussed. Methods Twenty female C57BL/6J were randomly divided into normal control group （ 10 mice） fed with standard chow and high fat diet group （ 10 mice）. Twelve weeks later, the weight and serum samples of all mice were measured. The concentrations of total choleSterOl （TC） triglyceride （TG） high density lipoprotein cholesterol （HDL- C）, and low density lipoprotein cholesterol （LDL- C） were determined using a commercial kit. Total bacterial DNA, from which feces samples from all mice were collected, was extracted and used to amplify PCR for 16S rDNA gene V4 tag fragment and sequenced using high - through put HiSeq 2500 technique. Based on the QIIME platform, the microbial community diversity in colonic content was compared. Results The body weights, the levels of serum total cholesterol （TC）, triglyceride （TG）, high density lipoprotein cholesterol （HDL- C）, and low density lipoprotein cholesterol （LDL- C） in high fat diet group increased significantly compared with normal control group. The richness and diversity of bacteria in normal Control group was higher than that in high fat diet group. In the phylum level, the relative abundance of Firmicutes was higher, while the proportion of Bacteroidetes was lower in high fat group compared with control group. Conclusion High fat diet can induce obesity in mice and change the structure of intestinal flora in mice.