Effect Of Sodium Butyrate On The Expression Of IL-21 And IL-10 In DSS-induced Experimental Colitis Mice

Objective: The purpose of this study was to investigate the effects of different doses of sodium butyrate on IL-21 and IL-10 in mice with colitis induced by dextran sodium sulfate(DSS)and their effects on colitis.Methods: Fifty healthy C57BL/6J mice aged 6-8 weeks were randomly divided into five groups(n=10 mice per group),normal group,model group,sodium butyrate low-dose group(SB300mg/kg),sodium butyrate medium-dose group(SB450mg/kg),sodium butyrate high-dose group(SB600mg/kg).Normal group was free to drink water for 7 days,model group and sodium butyrate low,medium and high dose groups were induced colitis through free access to 2.5%DSS solution.Sodium butyrate low,medium and high dose groups were administered 300,450,and 600 mg/kg sodium butyrate solution orally,once a day,maintaining the same time,from day 1 to day 7,normal and model groups were administered distilled water by oral gavage.All mice were sacrificed on the day8.The disease activity index score(DAI)was calculated according to weight loss,stool consistency and stool bleeding.Blood and colonic specimen were collected.Pathological examination of colonic specimen was performed by H&E staining.The expression levels of Foxp3,IL-21 and IL-10 mRNA in colon were detected by polymerase chain reaction(PCR),and the expression levels of IL-21 and IL-10 in serum were detected by enzyme-linked immunosorbent assay(ELISA).Results: Compared with the normal group,the body weight of the model group and sodium butyrate low,medium and high dose groups decreased significantly(p<0.05),and the scores of disease activity index(DAI)and histopathology increased significantly(p<0.05).Compared with the model group,the scores of DAI and histopathology in sodium butyrate low-dose group(SB300mg/kg)and sodium butyrate medium-dose group(SB450mg/kg)had no significant different(p>0.05),while both were decreased in sodium butyrate highdose group(SB600mg/kg)(p<0.05).Compared with the normal group,the relative expression levels of Foxp3 mRNA,IL-21 mRNA and IL-10 mRNA in colon tissue of model group and sodium butyrate low,medium and high dose groups were increased(p<0.05).Compared with the model group,the relative expression levels of Foxp3 mRNA,IL-21 mRNA and IL-10 mRNA in colon tissue of sodium butyrate low-dose group(SB300mg/kg)and sodium butyrate mediumdose group(SB450mg/kg)had no significant difference(p>0.05);the relative expression levels of Foxp3 mRNA and IL-10 mRNA in colonic tissue of sodium butyrate high-dose group(SB600mg/kg)increased(p<0.05),while the relative expression level of IL-21 mRNA decreased(p<0.05).Compared with the normal group,the expression levels of IL-21 and IL-10 in serum of the model group and the sodium butyrate low,medium and high dose groups were increased(p<0.05).Compared with the model group,the expression levels of IL-21 and IL-10 in serum of sodium butyrate low-dose group(SB300mg/kg)and sodium butyrate medium-dose group(SB450mg/kg)had no significant different(p>0.05);the expression level of IL-21 in serum of sodium butyrate high-dose group(SB600mg/kg)decreased(p<0.05),while the expression level of IL-10 increased(p<0.05).Conclusion: Sodium butyrate(SB600mg/kg)can inhibit the expression of inflammatory factor IL-21 and promote the expression of anti-inflammatory factor IL-10 in a dose-dependent manner,and alleviate intestinal inflammation of DSS-induced colitis in mice.Thus,it has a potential anti-inflammatory effect.