高剂量单宁酸对小鼠肠道屏障和肠道菌群的影响

Effects of High-dose Tannic Acid on the Intestinal Barrier Function and Gut Microbiota in Mice

以正常饮食小鼠和高脂饮食诱导肥胖模型小鼠为对象,研究高剂量单宁酸对小鼠肠道屏障及肠道菌群的影响。通过H&E染色、RT-qPCR、16S rRNA测序等方法进行检测分析。研究发现高剂量单宁酸(400 mg/kg BW)灌胃可使小鼠的体重和进食量降低,增加小鼠体内各肠段内容物的含量,其中结肠内容物的含量显著增加。并且高剂量单宁酸干预后可造成肠道功能损伤及肠道屏障破坏,如杯状细胞数量和隐窝长度减少,及肠道紧密连接蛋白(ZO-1,Occludin及Claudin)表达降低。此外,口服高剂量单宁酸会导致小鼠结肠肠道菌群的多样性发生变化,并增加了SCFA产生菌Alistipes,Ruminococcus和Blautia以及肥胖负相关菌群Alistipes和Oscillibacter的含量。结果表明,高剂量单宁酸对肠黏膜屏障的破坏影响了小鼠对食物的消化吸收,这可能是高剂量单宁酸干预后小鼠体重快速下降的主要潜在原因。另一方面,高剂量单宁酸所造成的肠道菌群变化也会对小鼠的体重产生影响。

The objective of this study is to analyze the effects of high-dose tannic acid on the intestinal barrier and gut microbiota in normal-diet mice and high-fat diet-induced obese model mice.H&E staining,RT-qPCR,16S rRNA sequencing and other methods were used for detection and analysis.It was found that the intervention of high-dose tannic acid(400 mg/kg)reduced the body weights and food intakes of the mice,and increased the contents of various intestinal segments in the mice,among which the colon content significantly increased.In addition,high-dose tannic acid damaged the intestinal function and intestinal barrier,such as reduced the number of goblet cell and the length of crypt,and decreased intestinal tight junction protein(ZO-1,Occludin,and Claudin)expression.Moreover,oral administration of highdose tannic acid changed the diversity of gut microbiota in the colon,and increased the abundance of SCFAs-producing bacteria Alistipes,Ruminococcus and Blautia,as well as obesity negatively related bacteria Alistipes and Oscillibacter.In conclusion,the results showed that the damage of intestinal mucosal barrier caused by high-dose tannic acid affected the digestion and absorption of food in mice,which might be the main potential reason for the rapid weight loss in the mice after the intervention of high-dose tannic acid.On the other hand,the changes of gut microbiota caused by high-dose tannic acid also had an effect on the body weights of the mice.