Efeito protetor da epiisopiloturina no modelo experimental de mucosite intestinal induzida por 5-fluorouracil em camundongos: papel da via no/ cox

Abstract

Intestinal mucositis (MI) is a side effect of the chemotherapy 5-Fluorouracil (5-FU), which does not yet have effective treatment, so that products of natural origin have been widely researched as a therapeutic proposal for this pathology. Epiisopiloturin (EPI) is an alkaloid derived from Pilocarpus microphyllus Stapf ex Wardleworth, which has antinociceptive, anthelmintic, antioxidant, anti-inflammatory potential. Thus, since MI is a pathological condition characterized by inflammation and PPE is a potentially anti-inflammatory compound, the objective of this study was to evaluate the effect of EPI on IM induced by 5-FU. Initially, the OECD protocol for the toxicological evaluation. The animals received high doses of EPI orally and then were observed for 14 days and evaluated for the number of circulating leukocytes, weight variation, feed intake, water and relative weight of the organs (kidneys, liver, spleen, heart and testis ). Subsequently, the effect of EPI on MI was investigated, animals were submitted to MI induction by intraperitoneal (i.p) administration of 5-FU (450 mg / kg) and treated with i.p. EPI for four days. After euthanasia, the duodenum, jejunum and ileum were removed to evaluate the effect of EPI on mucositis, through the parameters of weight variation, number of circulating leukocytes, histopathological analysis, morphometric analysis and mast cell count. After this phase the dose of 10 mg / kg and the jejunum segment were selected for the execution of the same protocol, but with the use of the selective COX-2 inhibitor (Celecoxib).The dosage of Malondialdehyde (MDA), the number of goblet cells, and the involvement of COX-2 in IM were evaluated by immunohistochemistry. Finally, modulation of nitric oxide (NO) in MI with L-NAME and L-arginine was performed, the involvement of NO was evaluated by immunohistochemistry for iNOS and molecular docking. It was found that the animals treated with EPI had no clinical signs of toxicity or changes in the number of circulating leukocytes and relative body weight. It was also observed that in IM, PPE did not attenuate weight loss, but was able to prevent morphometric, histopathological and leucopenia changes, prevented the increase of mast cells, reduce MDA dosage and preserved goblet cells as well as a statistically significant decrease in the immunolabelled area for COX-2 and iNOS, associated with the strong molecular interaction of EPI with iNOS. In view of this, it was verified that EPI is not very toxic and showed a protective effect on intestinal mucositis induced by 5- FU, reducing inflammatory and oxidative parameters with COX-2 and NO pathway.