Study On Effects Of Erchen Decoction On IL-1? And IL-6 In The Phlegm Syndrome Rat Model With Inflammatory Bowel Disease Induced By DSS/AOM Combined With High-fat Diet

Objective: A Rat model of inflammatory bowel disease(IBD)with Phlegm syndr ome induced by high-fat diet and Dextran sodium sulfate(DSS)/Azoxymethane(AOM).Erchen Decoction,a classical phlegm-resolving prescription,was used to treat.the phle gm-IBD model.the relationship between phlegm Syndrome and inflammatory factors a nd the mechanism of Erchen Decoction on IBD was explorsed by observing the levels of serum interleukin-1?(IL-1?),interleukin-6(IL-6)and C-reactive protein(CRP),an d the expression of IL-1? and IL-6 in large intestine in rats of each group.Methods: Fifty male Wistar rats were randomly divided into five groups after on e week of adaptive feeding: Control group,IBD group,phlegm syndrome group,phleg m-IBD syndrome group and Phlegm dispersing group.Control group and IBD group were fed with normal diet;phlegm syndrome group,IBD phlegm syndrome group and resolving phlegm group were fed with high fat diet.After 4-weeks high fat diet feed ing to induce phlegm syndrom,rats in the IBD group,IBD phlegm syndrome group a nd phlegm-reducing group drank 2% DSS for 1 week,and were injected with AOM(15mg/kg)once per week at the 6th and 7th week respectively.From the 5th week,t he phlegm-reducing group was given Erchen Decoction for 16 weeks,and the other fo ur groups were given equal volume normal saline for 16 weeks.At the end of the 6t h week,calculated disease activity index scores with each group rats.Rats were sacrif iced after abdominal aorta blood collection.Histopathological changes of large intestine observed by HE staining.Serum levels of IL-1?,IL-6 and CRP in rats were quantifi ed by ELISA.Expression of IL-1? and IL-6 mRNA in large intestine were detected b y Real-time PCR.Protein of IL-1? and IL-6 in liver and large intestine were detected by immunohistochemistry.Results:1.Comparison of body weight and Lee's index of different groups.At the end of the 4th week,compared with the control group,the body weight and Lee's of phleg m syndrome group increased significantly(P<0.05).At the end of the 20 th week,the body weight and Lee's index of the phlegm syndrome group increased significantly compared with the control group(P<0.01);the body weight and Lee's index of the IBD phlegm syndrome group increased significantly compared with the IBD group(P<0.01);Compared with phlegm-IBD syndrome group,the body weight and Lee's index of phlegm-reducing group decreased,but the difference is not statistically significant.2.Comparison of blood lipid levels at the 20 th week.At the 20 th week,TC of t he phlegm syndrome group was significantly higher than that of the control group(P<0.05);TC of the phlegm-IBD group was significantly higher than that in the IBD gro up(P<0.05);TC in phlegm dispersing group was significantly lower than that in the phlegm-IBD group(P<0.05).Serum triglyceride(TG)of the phlegm syndrome group was significantly higher than that of the control group(P<0.05);TG in the phlegm-IB D group was significantly higher than that of the IBD group(P<0.05).Serum Low-de nsity lipoprotein cholesterol(LDL-C)was observed with significant increase in the phl egm syndrome group than in the control group(P<0.05),while LDL-C in the phlegmIBD group was significantly higher than that in the IBD group(P<0.05).3.Comparison of disease activity index scores.Compared with the IBD group,th e score of disease activity index of the phlegm-IBD group increased significantly(P<0.05).Compared with phlegm-IBD group,the score index of disease activity index of ra ts in the phlegm-reducing group decreased significantly(P<0.05).4.Comparison the length of large intestine.Compared with the control group,the length of large intestine of the IBD group was significantly shorter(P<0.05).No sig nificant difference of the length of large intestine was observed between the IBD grou p and the phlegm-IBD group.Compared with the phlegm-IBD group,the length of lar ge intestine of the phlegm-reduciig group increased significantly(P<0.01).5.HE staining.Compared with the control group,the colonic mucosa structure of IBD group was damaged,sparse and disordered,and some glands were incomplete.I nflammatory cell infiltration was observed in mucosa and submucosa.Inflammatory cel l infiltration in IBD phlegm syndrome group was more serious than that in IBD grou p.Compared with the IBD phlegm syndrome group,the mucosal ulcer in the phlegm dispersing group was healed and repaired,with no obvious loss of structure and less i nflammatory cell infiltration.6.Comparison of serum IL-1?,IL-6 and CRP.Compared with the IBD group,th e serum levels of IL-1?,IL-6 and CRP of the phlegm-IBD group increased significant ly(P<0.01).Compared with phlegm-IBD group,the levels of IL-1? and IL-6 in seru m in phlegm-reducing group decreased significantly(P<0.05),and the levels of CRP i n serum in phlegm-reducing group decreased significantly(P<0.01).7.Comparison of IL-1? and IL-6 mRNA expression in large intestine.The expres sion of IL-1? and IL-6 mRNA in large intestine of the phlegm-IBD group increased s ignificantly(P<0.01)compared with the IBD group.Compared with IBD phlegm synd rome group,the expression of Either IL-1? or IL-6 in large intestine of rats in phleg m resolving group was significantly lower(P<0.05)than in phlegm-IBD group.8.Immunohistochemical analysis of IL-1? and IL-6 in large intestine and liver In large intestine tissue,,IL-1? and IL-6 were significantly higher of phlegm-IBD group than the IBD group(P<0.01).IL-1? and IL-6 in phlegm-reducing group were signific antly lower(P<0.01)than that of phlegm-IBD group.In liver,IL-1? and IL-6 of the phlegm-IBD group were significantly higher(P<0.01)than that of the IBD group;the integral optical densities of IL-1? and IL-6 in phlegm-reducing group decreased signif icantly(P<0.01)compared with phlegm-IBD group.Conclusion:1.Long-term high-fat diet induced phlegm syndrome could aggravate inflammatory bowel disease in rats.2.The increase of inflammatory cytokines may play a role in the mechanisms of TCM phlegm syndrom.3.Erchen decoction can reduce the levels of inflammatory cytokines IL-1? and I L-6 in the phlegm syndrome rat model with inflammatory bowel disease.