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.