Avaliação do efeito da losartana e do probiótico Limosilactobacillus mucosae CNPC007 no modelo experimental de mucosite intestinal induzido por 5-fluorouracil em camundongos

Abstract

Intestinal mucositis (IM) is a side effect associated with cancer treatment resulting from chemotherapy. IM cytotoxicity resulting from the use of 5-fluorouracil (5-FU) promotes damage to the mucosal epithelial structure and associated gastrointestinal symptoms that induce the patient to discontinue treatment. Currently, there is no efficient therapeutic protocol that improves the symptoms of intestinal mucositis, in this sense, to propose alternatives that aim to attenuate the symptoms presented by patients affected by IM, the objective of the present study was to evaluate the effect of losartan (LOS) and the protective effect of the probiotic (Pb) Limosilactobacillus mucosae CNPC 007 on 5-FU-induced intestinal mucositis in Swiss mice. 5-FU (450 mg/kg, i.p.) was used to induce intestinal mucositis on day 1. Experimental groups included: Saline Group, 5-FU Group, LOS Group (5, 25 or 50 mg/Kg) and Probiotic Group. Losartan was administered 30 min before 5-FU and the probiotic was administered 14 days prior to IM induction. These were euthanized with thiopental (90 mg/kg, i.p.) on the 4th day after induction and blood samples and intestinal segments were collected for further analysis. Blood samples were used for leukocyte count and jejunal segments were separated for enzyme immunosorbent assays for cytokine (TNF-α and IL-1β), oxidative stress (MDA and GSH) and quantitative polymerase chain reactions in time. real (qPCR) for TWEAK, Fn-14 and NF-κB p65 and MUC-2 genes. The animals with untreated IM showed greater intestinal damage in the jejunal portion, observed by shortened villi, loss of crypt architecture and intense inflammatory cell infiltrate, evaluated by histopathological analysis with scores 3 (range 2-3) and morphometry (p < 0.001 vs saline group). LOS 50 mg/Kg presented the best results for the initial analyses, being this the dose adopted for the evaluation of the study. Leukopenia and greater weight loss were observed in the animals with IM (Group 5-FU), compared to the Saline Group. The treatment of the LOS 50 and Probiotic groups significantly improved the appearance of the villi and crypts (p < 0,01), reversing the histopathological changes (scores 1, range 1-2) and morphometry, leukopenia, and weight loss (p < 0,05 vs 5-FU group), induced by 5-FU. There was a reduction in the levels of tumor necrosis factor (TNF)-α and interleukin (IL)-1β cytokines for the LOS 50 and Probiotic groups. LOS 50 reduced oxidative stress markers and NF-κB p65, TWEAK and Fn-14 gene expression compared to the 5-FU group (p < 0.001). The probiotic reduced p65 NF-κB gene expression and increased MUC-2 expression compared to the untreated group (saline, p < 0,001). These results showed a beneficial effect of LOS 50 and Limosilactobacillus mucosae CNPC 007 on induced MI in mice. In conclusion, LOS 50 mg/Kg and the probiotic L. mucosae CNPC 007 showed promise in attenuating IM symptoms, considering that both treatments improved 5-FU-induced IM injury, reducing the expression of pro-inflammatory mediators. in evaluated jejunal segments.