A comparison of the intestinal phenotype and transcriptome profile analysis in the oral-fed mice with substances to affect the intestinal homeostasis

Epithelial cells in the intestinal mucosa maintain gut homeostasis by interacting with different types of microbiota. Proper appropriate immune responses in the intestinal epithelium are essential for the preservation of the intestinal homeostasis. In the present study, we aimed to identify genotypic and phenotypic changes in mice following oral feeding of various substances which has been shown to differentially affect intestinal homeostasis. We orally fed C57BL/6 mice for either one or seven days with one of the four substances: dextran sulfate sodium (DSS); Typhoid VI Polysaccharide vaccine (Vi vaccine); antibiotic cocktails (AB) of ampicillin, vancomycin, neomycin, and metronidazole; or(probiotics)consisting of Lactobacillus Rhamnosus R0011and L. Acidophilus R0052.While DSS and AB feeding resulted in severe gut pathology characterized by infiltration of inflammatory cells, epithelium shedding, and distortion of paneth cells. Vi vaccine and probiotics feeding resulted in phenotypic improvement of the gut health characterized by epithelial cell proliferation and increased formation of tight junctions between epithelial cells. Interestingly, microarray data showed significant increase in the expression levels of genes regulating cell proliferation and intestinal homeostasis in the gut epithelium of probiotics-and Vi vaccine-fed mice compared to DSS-or AB-fed mice. In addition, expression levels of genes regulating cell death and inflammation were significantly increased in the gut epithelium of DSS- and AB-fed mice. These results suggest that intestinal homeostasis play a pivotal role in maintaining gut health and, subsequently, in protecting host against enteric bacteria and external pathogens infection.

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