Clinical and immunological analysis of the effectiveness of local application of vitamin D<sub>3</sub> in experimental colitis

Abstract

The pathogenesis of inflammatory bowel diseases has not been fully studied, and the therapies used have side effects that limit their use.The purpose of this study is to conduct a clinical and immunological analysis of the effectiveness of vitamin D3 in the original rectal suppositories in experimental colitis (EC).EC was modeled with oxazolone. Original suppositories with vitamin D3 in group 3 and 5-ASA in group 4 were used per rectum. The clinic was evaluated on the Disease activity index scale. The expression of MPO and TNFa, the content of neutrophils, lymphocytes, eosinophils, histiocytes, plasmocytes, fibroblasts, ulcerative defect, tissue damage index were determined in the focus of colon injury. The study was carried out on days 2, 4 and 6.With EC, DAI increases for the entire day, MPO and TNFa increase in the lesion, ulcerative defect isfixed, neutrophil-lymphocytic infiltration increases, and TDI increases. When comparing the morphometric parameters of the alteration zone in EC under the conditions of vitamin D3 use, in contrast to the use of 5-ASA, a decrease in the number of lymphocytes, an increase in fibroblasts was revealed on day 2, a decrease in the number of plasmocytes and an increase in fibroblasts on day 4, an increase in the number of histiocytes and fibroblasts on day 6. The diameter of the ulcerative defect and the TDI index have no significant differences between the compared groups. When comparing the effectiveness of vitamin D3, in contrast to the use of 5-ASA, the MPO content is higher on day 6; the TNFa content is higher on day 4.In EC, the effects of using rectal suppositories with vitamin D3 on clinical signs, the size of the ulcerative defect, the content of MPO and TNFa in the lesion are comparable to the effects of using rectal suppositories with 50 mg of 5-ASA; more pronounced with respect to the dynamics of the cellular composition of the lesion of the colon.