Effects Of Faecalibacterium Prausnitzii On Treg Cell,IL-10 And TGF-?1 In Mice With Dextran Sulfate Sodium-induced Ulcerative Colitis

Backgroud:Faecalibacterium prausnitzii is one of the most abundant anaerobic bacteria in human intestine.It was found obviously decreased in the gut of patients with inflammatory bowel disease(IBD),and has a protective effect on IBD.Regulatory T cells(Treg)exert an immunosuppresive role in IBD,and was decreased in peripheral blood of patients with IBD.Aim:To explore the effect of Faecalibacterium prausnitzii and its supernatant on Treg cells,IL-10 and TGF-?1 in mice with dextran sulfate sodium-induced ulcerative colitis.Methods:Total of twenty-four C57BL/6J male mice was randomly divided into normal control group,colitis control group,FP-intervened colitis group and FP supernatant-intervened colitis group.Colitis model was induced by drinking 3.5%DSS solution at the sixth day;the two intervened colitis groups were administered intragastrically with FP and its supernatant respectively from the first to the last day.The colorectal histopathologic damage score(HDS)were calculated.The proportion of Treg cells in spleen was analyzed by flow cytometry.The levels of IL-10 and TGF-?1 in plasma were detected by ELISA and the mRNA levels of IL-10 and TGF-?1 in colon mucosa tissues were also determined by real time PCR.Results:Compared with the colitis control group,the colon HDS in the FP-intervened colitis group and FP supernatant-intervened colitis group were significantly decreased(both P<0.05),but there was no significant difference in the two intervened groups.The proportion of CD4+CD25+Foxp3+Treg cells in spleen in the colitis control group was lower than that in the normal control group(P<0.01).The proportion of CD4+CD25+Foxp3+Treg cells in spleen in the FP-intervened colitis group and FP supernatant-intervened colitis group were higher than that in the colitis control group(P<0.05).The levels of IL-10 and TGF-?1 in plasma in the colitis control group were significantly higher than those in the normal control group(P<0.01);the levels of IL-10 and TGF-?1 in plasma in the FP supernatant-intervened colitis group were obviously higher than those in the colitis control group(P<0.01);the level of TGF-?1 in plasma in the FP-intervened colitis group was higher than that in the colitis control group(P<0.05).The mRNA expression levels of Foxp3,IL-10 and TGF-?1 in the colon mucosa tissues in the colitis control group were higher than those in the normal control group(P<0.05).The mRNA expression level of Foxp3 in the colon mucosa tissues in the FP-intervened colitis group was higher than that in the colitis control group(P<0.05).The mRNA expression levels of Foxp3 and TGF-?1 in the colon mucosa tissues in the FP supernatant-intervened colitis group were higher than those in the colitis control group(P<0.05).Conclusion:Faecalibacterium prausnitzii and its supernatant both can treat mice with dextran sulfate sodium-induced ulcerative colitis.This function might be medicated by the increase of CD4+CD25+Foxp3+Treg cells and levels of IL-10 and TGF-?1,anti-inflammatory cytokines which CD4+CD25+Foxp3+Treg cells secreted.The anti-inflammatory effect of Faecalibacterium prausnitzii supernatant displayed stronger than that of Faecalibacterium prausnitzii.