Pathological and bacteriological studies on the effect of vitamin C on the small intestine of rabbit experimentally infected with E. coli O103:K-:H22 (E22)

A well-established rabbit model infected with reference strain of enteropathogenic E. coli (EPEC) {E coli O103:K-:H22 (E22)} was used to examine whether vitamin C (VC) nutritional supplementation had an effect on the pathological changes induced in the bowel by EPEC{E. coli O103:K-:H22 (E22)}.
In this study artificial infection model, weaned female rabbits were infected with E. coli O103:K-:H22 (E22) and infected tissues were evaluated by light microscopy. Twenty-three rabbits were used in this study. They divided into five groups(first group of rabbits  were used as control (3 rabbits), second group were treated with vitamin C (60mg/kg) in drinking water (5 rabbit),third group were infected with E. coli {O103:K-:H22 (E22)} (5 rabbits) ,fourth group of rabbits infected with E. coli {O103:K-:H22 (E22)} and treated with vitamin C (60mg/kg) in drinking water (5 rabbits),and fifth group were infected with E. coli {O103:K-:H22 (E22)} and injected with antibiotic, ceftazidime) 5ml for each rabbit, and treated with vitamin C (60mg/kg) (5 rabbits). Rabbits were treated daily pre- experiment with an oral dose of vitamin C(60mg/kg)for ten days. The percentages of bacterial isolation of E22 from fecal samples of rabbits after inoculated with {E. coli O103:K-:H22 (E22)}reference strain in four groups were (20,80,20 and 40%) in second, third, fourth and fifth group receptively. These results indicated that Vitamin C did not affect EPEC (REPEC) strain ‘‘E22’’. Whereas the pathological changes  after inoculation with E. coliO103:K-:H22 (E22) reference strain in rabbit model were hyperplasia of ileal payer's patches, in some animal intestinal epithelial ulceration was found with lymphocytic infiltration. Liver showed hydropic degeneration, area of necrosis with hemorrhages and few lymphocytic infiltration. Vitamin C did not affect EPEC (REPEC) strain ‘‘E22’’ (O103:K-:H2,  colonization and did not give significant protection against EPEC-induced changes and diarrhea. Although it had no effect on the EPEC-related increase of enterocyte apoptosis, it clearly contributed to an acceleration of epithelial cell proliferation in the ileal crypts. We showed that Vitamin C ameliorated somewhat the effects of EPEC on intestinal mucosal architecture. Showing hyperplasia of jejunal villi, payer's patches, ileum and mucous gland .There are also leucocytic infiltration in lamina propria..