The Experimental Study Of Lactobacillus Acidophilus In The Treatment Of Rat Pouchitis

Therat ileal pouch-anal anastomosis(IPAA) model was established by microsurgical technique and then Dextran sodium sulfate(DSS) was used to induce rats pouchitis verified by fecal and histopathologicalscore, the inflammatory markers(IL-1?, IL-6, IL-10 and TNF-?) m RNA expression before and after intervention. Following Lactobacillus acidophilustreatment to rat pouchitis,theparameters above and ZO-1protein were valued to evaluat effection and mechanism of the probiotics.Part 1 Themodeling of Rat PouchitisObjective: Building rat IPAA model and iduce rats pouchitisby microsurgery and DSS separately. Methods: Microsurgery was used to establish IPAA model, the model rats were randomly divided into sham, IPAA and IPAA with DSS(IPAA+DSS) group(100 ml 4% DSS solution 4 days after 31 days postoperative).During the experiment records each rat body weight change, bloody situation, excrement characters(score).Taking terminal ileum tissue from sham rats, and pouch from IPAA and ID rats forhistologic grading;Real-time fluorescent quantitative PCR detected IL-1?, IL-6, IL-10 and TNF-? m RNA expression level.Results:The postoperative rats' weight reached to lowest level(285.47±10.30)gat(9.42±1.44) days;IPAA+DSSrats' weight lose(72.92±6.60)gafter with DSS. All rats in IPAA+DSS group had bloody stool(6/6),the fecal scoreswere inferior to IPAA Sham group(F = 350.4, P < 0.05);The histological scores in IPAA+DSS were higher than sham and IPAA group(F =573.8, P < 0.05), and scores in IPAA were grater than sham group(t = 20.55, P < 0.05).There were more IL-1?, IL-6, and TNF-? m RNA expression(F=886.4,P<0.05;F=773.1,P<0.05;F=575.2,P<0.05) and less IL-10(F = 536.3, P < 0.05) in IPAA+DSS compared to other two groups. There were more IL-1?, IL-6, and TNF-? m RNA expression(t=16.47,P<0.05;t=8.29,P<0.05;t=16.05,P<0.05)and less IL-10(t=14.24,P<0.05) in IPAA compared to sham. Conclusion: The rats IPAA model can be induced pouchitis with a reasonable DSS feeding.Part 2 Thetherapeuticeffect of Lactobacillus acidophilusin Rat PouchitisObjective: To evaluate the therapeutic effect of Lactobacillus acidophilus to rat pouchitis. Methods: The rats pouchitis model were randomly divided intonormal saline(NS), Lactobacillus acidophilus(LA) and no intervention(NI) groups, and were separatelygiven 1 ml saline, 1 x 1010 CFU(3ml)Lactobacillus acidophilusby lavaging and no intervention 7 days.During the experiment records each rat body weight change, bloody situation, excrement characters(score).Taking pouchforhistologic grading;Real-time fluorescent quantitative PCR detected IL-1?, IL-6, IL-10 and TNF-?m RNA expression level.Immunohistochemistry method was used to measure ZO-1 protein. Results:Rats in LA loss less weight than that of NS and NI groups, the difference was statistically significant(F = 61.34, P < 0.05).In LA group,blood disappears in 3.17±0.75 day, NS and NI group were 6.5±0.55 and 6.17±0.75 days.Fecal scores were obviously improved in LA group,higher than that of NS and NI groups(F =108.7, P < 0.05). Pouch histopathologic scoreswere lower in LA group compared to other two groups(F = 31.23, P < 0.05).There were less IL-1?, IL-6, and TNF-? m RNA expression(F=373.6,P<0.05;F=285.5,P<0.05;F=132.9,P<0.05)and more IL-10(F = 61.05, P < 0.05) in LA compared to other two groups.ZO-1 expression level was higher in LA than that of NS and NI groups(F = 8.23, P < 0.05). Inflammatory factor and ZO-1expression showed no difference between NS and NI groups(all P > 0.05). Conclusion:Lactobacillus acidophilus can treat the pouch inflammation. The possible mechanism was that the probiotics could inhibit IL-1?, IL-6 and TNF-? and promote the expression of IL-10 and ZO-1 protein to reduce pouch inflammation and improve the intestinal barrier function.