Effects of probiotics on the gut flora and mucosal tumor necrosis factor?expression in rats with experimental colitis / 中华消化杂志

ABSTRACT

Objective To evaluate the effects of probioties on inflammation,intestinal flora and mucosal tumor necrosis factor alpha(TNF-?)expression in experimental colitis rats.Methods Thirty Wistar rats were randomly divided into normal control group(NC),model control group(UC),and pro- biotics treatment group(PC).The experimental colitis were induced by trinitrobenzene sulfonie acid (TNBS)/ethanol enema.Rats in PC group were fed with Bifico[live probiotics of combined bifidobacte- rium(Bif),lactobacillus (Lac) and enterococcus]by 2.2?10~9 colony-forming unit (CFU)/d for 4 weeks.Inflammatory scores and mucosal morphological changes under light microscopy were studied. Plasma endotoxin levels,expressions of TNF-?and interleukin-6 (IL-6) in mueosa were measured. Enteric microorganisms in cecum were fostered with standard methods.Results Inflammatory scores in PC group decreased compared with those in UC group(7.94?0.85 vs 10.25?1.36,P＜0.05),but still higher than those in NC group(7.94?0.85 vs 4.35?0.88,P＜0.01).There was a significant alteration in the enteric microbial flora,Bif and Lac were decreased significantly in UC group,Bifico supplement ameliorated this imbalance.Plasma endotoxin and mucosal TNF-?levels in PC were lower than those in UC group[endotoxin(93.33?21.22)pg/ml vs (121.25?39.07)pg/ml;TNF-?67.51?14.63 vs 85.99?18.17,P＜0.05],but higher than those in NC group[endotoxin(93.33?21.22) pg/ml vs(35.20?15.12)pg/ml;TNF+?67.51?14.63 vs 43.28 4?19.98,P＜0.01].There was no statistically significant difference in mucosal IL-6 levels between PC group and UC group,though its level in PC group was lower than that in UC group(155.22?34.01 vs 184.09?29.11,P＞0.05),but higher than that in NC group(155.22?34.01 vs 108.73?37.35,P＜0.01).Conclusions Probiotics can attenuate inflammation of experimental colitis of rats through reinstituting gut flora bal- anee.Improving gut flora imbalance,reducing endotoxin and pro-inflammatory cytokines may be the effects of probiotics.