Effect of antibiotic-induced microbiota dysbiosis on colonic mucosal barrier and immune response in juvenile mice / 中华实用儿科临床杂志

ABSTRACT

Objective To investigate the effect of antibiotic-induced microbiota dysbiosis on colonic barrier and immune response in juvenile mice.Methods Twenty Balb/c mice were randomly divided into experimental group and control group.Broad spectrum antibiotic mixture were administered by means of gavage to the experimental group every 12 hours for 14 days to induce intestinal microbiota dysbiosis.The mice of control group were given an equal amount of physiological saline.On the 15th day,all mice were intraperitoneally injected with lipopolysaccharide(LPS) to induce intestinal inflammatory reaction.The structure of intestinal flora was analyzed by way of 16SrRNA sequencing,and the morphology of colonic mucosa was observed by means of HE staining.The infiltration of colonic mucosa was observed through toluidine blue staining and immunohistochemistry.The levels of inflammatory cytokines in colon tissue were measured by real-time PCR and intestinal permeability-related parameters were measured by enzyme-linked immunosorbent assay.Results The intestinal microbial composition of the experimental group was significantly changed,and the expression levels of inflammatory cytokines interleukin (IL)-1β,IL-6,IL-8,IL-10,tumor necrosis factor (TNF)-α mRNA in the antibiotic group (0.765 ± 0.062,0.082 ± 0.040,0.442 ± 0.059,0.469 ±0.079,0.736 ± 0.063) were all lower than those in the control group (1.738 ± 0.243,1.090 ± 0.104,1.151 ±0.136,1.066 ± 0.102,1.539 ± 0.218),and the differences were statistically significant (all P ＜ 0.05).The expressions of intestinal barrier related gene of mice ZO-1 and Occludin decreased (0.639 ± 0.071 vs.1.347 ± 0.224,0.770 ±0.067 vs.1.487 ± 0.148) but the level of fecal albumin increased [(6.419 ± 0.552) mg/L vs.(6.079 ± 0.011) mg/L] after antibiotic exposure,and the differences were statistically significant (all P ＜ 0.05).Conclusions Antibiotic exposure leads to changes of enteric microbiota,which adversely affects local mucosal immunity and intestinal barrier function of colon in juvenile mice.