连翘叶改善肥胖大鼠炎症因子水平及肠道菌群结构的作用OA北大核心CSTPCD

Objective:To observe the effect of forsythia leaves on inflammatory factor levels in obese rats and the structure of the intestinal flora and the analysis of its action mechanism.Methods:Forty SPF-grade SD male rats were randomly divided into blank group(n=8)and model group(n=32)according to body weight.The blank group was fed with normal diet,and the model group was fed with high-fat diet.After nine weeks of feeding,the rats that failed to establish the model were finally determined as the model group and forsythia leaf treatment group,with eight rats in each group.The forsythia leaf treatment group was given for-sythia leaf freeze-dried powder 0.067 g·kg-1·d-1 by gavage,and the blank group and the model group were given the same dose of normal saline by gavage for 10 weeks.At the end of the intervention,the body weight,liver weight,visceral fat weight and body length were measured,and the obesity index,fat coefficient and liver coefficient were calculated.The serum levels of tumor necro-sis factor-α(TNF-α),interleukin-6(IL-6)and lipopolysaccharide(LPS)were detected by ELISA.Hematoxylin and eosin(HE)staining was used to observe the pathological changes of liver and colon.Oil red O staining was used to observe liver lipid deposi-tion.Immunohistochemistry was used to detect the protein expression of claudin-1,occludin and ZO-1 in colon.Metagenomic se-quencing technology was used to analyze the structure and function of intestinal flora.Results:Compared with the model group,the body weight and weight gain before and after administration in the forsythe leaf treatment group were decreased(P＜0.05),the adiposity index,fat coefficient and liver coefficient were decreased(P＜0.05),and the serum TNF-α,IL-6 and LPS levels were decreased(P＜0.05).The expression of tight junction proteins claudin-1 and ZO-1 in the colon was increased(P＜0.05),and the richness and diversity of intestinal flora were increased(P＜0.05).At the phylum level,the relative abundance of Fusobac-teria was increased(P＜0.05).At the genus level,the relative abundance of Prevotella and Pseudoflavonifractor increased(P＜0.05),while the relative abundance of Sarteria,Blautia and Eubacterium decreased(P＜0.05).The function of intestinal flora is increased in DNA damage repair and the disorder of amino acid metabolism is improved.Conclusion:Forsythia suspensa leaves can reduce obesity by improving the structure of intestinal flora and reducing the permeability of intestinal barrier,thereby reducing serum inflammation level.