Study On The Mechanism Of Compound Phellodendri Coating Based On Lgr5+ To Repair Colonic Mucosal Damage In UC Model Mice

Purpose: Compound Phellodendri coating is a compound preparation that has been tested for a long time and has good response,but its basic research is insufficient.This study makes use of high and low doses of Compound Phellodendri coating to intervene in Ulcerative colitis(UC)mice,which were induced by intestinal inflammatory response through free drinking Dextran Sulfate Sodium Salt(DSS)solution,and observes the effect of inflammation-related factors,anti-inflammation-related factors,Leucine-rich repeatcontaining G-protein coupled receptor 5(Lgr5)and Telomerase reverse transcriptase(TERT)on intestinal stem cells.The results can prove that It provides new experimental evidence for clinical application and explores new therapeutic approaches of Compound Phellodendri coating.Methods: Fifty C57BL/6N mice(25 males and 25 females)were randomly divided into blank group(blank),model group(model),mesalazine group(mesalazine,130mg/kg),high-dose Compound Phellodendri coating group(Dahuang,13ml/kg),and low-dose Compound Phellodendri coating group(Xiaohuang,3.25ml/kg).Except for the blank group,the other groups established the model by drinking 2%DSS solution for 5 days and water for9 days as a cycle,which was continuously consumed for four cycles.It starts in the third period that Mesalazine group,Dahuang group and Xiaohuang group were treated by intragastric administration of drug solution at their respective doses.The blank group and the model group were treated with the same volume of normal saline.The Disease Activity Index(DAI)of each group was calculated.Enzyme-linked immunosorbent assay(ELISA)was used to measure the levels of inflammatory and anti-inflammatory factors in the blood of mice with DSS-induced ulcerative colitis.Western blot(WB)was used to detect the expression of Lgr5 and TERT proteins in colon tissues.Results: The expression levels of intestinal stem cell marker proteins Lgr5 and TERT were significantly up-regulated by Compound Phellodendri coating,and the up-regulated protein levels were also different with different doses.The body weight,food intake and the ability to respond to external stimuli in the model group were significantly lower than those in the blank group(P<0.05),and the DAI score was significantly higher than that in the blank group(P<0.05).The results showed that after drinking DSS solution,mice showed clinical manifestations of UC,including loose stool,visible pus and blood,and colonic mucosa defects were observed in the colonic tissues of mice.After DSS-induced UC mice,the content of TNF-α in serum was significantly increased(P<0.05),the level of IL-22 was decreased(P<0.05),and the expression of Lgr5 and TERT in colon tissue was significantly decreased(P<0.05),indicating that the content of inflammatory related factors was increased and anti-inflammatory related factors were decreased in DSS-induced UC mice.DSS can inhibit the activity of intestinal stem cells in mice.Compared with the model group,the DAI scores of mesalazine group,Dahuang group and Xiaohuang group decreased(P<0.05).The expression of Lgr5 and TERT was up-regulated(P<0.05).The level of TNF-α was decreased(P<0.05),and the expression of IL-22 was increased(P<0.05),indicating that Huangbai ye could improve and alleviate DSS-induced UC mice by regulating the expression of inflammatory related factors,anti-inflammatory related factors and regulating the activity of intestinal stem cells.The results were consistent between male and female groups.Conclusion: Compound Phellodendri coating can improve the symptoms of UC mice and improve the general condition of mice.Compound Phellodendri coating can inhibit the up-regulation of inflammatory related factors and promote the production of antiinflammatory related factors,so as to alleviate the progression of inflammation and improve the symptoms of UC patients.At the same time,it may enhance the proliferation signal transduction of stem cells by regulating the expression of intestinal stem cell marker protein Lgr5,so as to promote the proliferation and differentiation of stem cells and repair intestinal mucosa,so as to achieve the purpose of treating UC.The experimental results also showed that the therapeutic effect of Compound Phellodendri coating was different with different doses,which basically showed dose-dependent changes.