The Effects Of Buzhongyiqi Prevention On NLRP3 Inflammasome Activation In Ulcerative Colitis Mice

Objective:The noncausal ulcerative colitis has another name called chronic nonspecific ulcerative colitis, and is a process of inflammation limited between colonic mucosal and submucous layer. New research shows that NLRP3 inflammasome play an important role in the inflammatory pathology of intestines in patients with UC, the specific mechanisms remain to be further studied. NLRP3 inflammasome which distributed widely throughout the gastrointestinal tract, can be activated by a number of stimulations, and then stimulate the production of IL-1β,IL-18, IL-33. Research suggests that the NLRP3 inflammasome is not only promoting inflammatory factor but also anti-inflammatory factor. Our previous study found that the mechanism of Buzhongyiqi to prevent the ulcerative colitis in mice could be reduce to inhibition of NLRP3, ASC, Caspase-1 mRNA expression to block the formation of nlrp3 inflammasome. In this experiment, we use the same method to cause ulcerative colitis mice and use buzhongyiqi to prevention to investigate the preventive effect of ulcerative colitis.I.The effects of buzhongyiqi prevention on the large intestine in ulcerative miceUC is an inflammatory bowel disease by abdominal pain, diarrhea, mucus and blood stool as the main clinical manifestations.To establish the UC mice and use buzhongyiqi for prevention. Evaluation of preventive effect of buzhongyiqi on UC mice by the intestinal symptoms of UC mice.Methods:240 female C57BL/6 mice were randomly divided into a normal group, a model group, a positive control group, a buzhongyiqi high dose group, middle dose group and low dose group,40 mice in each one. Mice in model group, positive control group, buzhongyiqiwan high dose group, middle dose group and low dose group were treated with 3%DSS instead of drinking water for 7 days. Mice in positive control group were treated with SASP 1.33g/kg everyday, mice in buzhongyiqi high dose group, middle dose group and low dose group, were treated with buzhongyiqiwan 12g/kg、 6g/kg、 3g/kg everyday, but mice in normal group and model group were treated with intragastric administration of distilled water 0.01 mL/g. All the groups were treated for 14 consecutive days. Pathologicalchanges in colonic mucosal of mice were observed in 1 week, 2 week,3 week,4 week.Result:Compared with the normal group, the model group pathological examination showed colon epithelial erosion, bleeding, multifocal ulcers and numerous inflammation cells infiltrating the mucosa and submucosa. However the symptoms were improved in other groups.2. Effect of buzhongyiqi on the NLRP3、 ASC、caspase-1 expression in colonic mucosalMethods:Molding, grouping, dosing were the same as the first experiment. Meanwhile mRNA expression of NLRP3, ASC and caspase-1 were detected by RT-PCR analysis.Result:In the first two weeks, the expression of NLRP3 mRNA in model group was obviously higher than normal group(P<0.05) and positive control group(P<0.05), but was not different from all the buzhongyiqi groups(P>0.05).The expression of ASC and caspase-1 mRNA in model group was obviously higher than the other groups. In the last two weeks, the expression of NLRP3, ASC, caspase-1 mRNA in model group was obviously higher than normal group (p<0.05). The expression of NLRP3 mRNA in positive control group and the buzhongyiqi groups lower than model group(p<0.05), but The expression of ASC, caspase-1 mRNA was obviously higher than model group (p<0.05).3. Effect of buzhongyiqi on the IL-1β, IL-18, IL-33 expression in plasma and colonic mucosalMethods:Molding, grouping,dosing were the same as the first experiment. Meanwhile IL-1β, IL-18, IL-33 expression were detected by ELISA analysis.Result:In the first week,the IL-1β, IL-18, IL-33 expression in model groups were higher than the other groups (P<0.05). In the second week, the IL-1β, IL-18, IL-33 expression in model groups were higher than normal group(p<0.05), and the IL-1β IL-18 expression were higher than other groups(p<0.05), but the IL-33 expression have no obvious difference between the positive control group and the buzhongyiqi groups. In the last two weeks, the IL-1β, IL-18,IL-33 expression in model groups still higher than normal group(P<0.05),but have no obvious difference between the positive control group and the buzhongyiqi groups.Gonclusion:The results show that buzhongyiqi can prevent the acute ulcerative colitis by inhibit NLRP3 inflammasome, buzhongyiqi can prevent chronic ulcerative colitis by promote NLRP3 inflammasome.