RESUMO
This study investigated the therapeutic role of polysaccharides from M. charantia and their mechanism of action against ethanol-induced gastric ulcers in rats. Their effects were determined through macroscopic evaluation of the gastric cavity (gastric ulcer index [GUI]), changes in PGE2, lipid peroxidation (malondialdehyde), antioxidant systems (catalase and reduced glutathione), inflammatory markers (tumor necrosis factor-α [TNF-α], interleukin-6 [IL-6], and myeloperoxidase [MPO]), apoptotic markers (caspase 3, Bax, and Bcl-2), nuclear factor-κB (NF-κB [p65]), and histopathological staining (H&E and PAS). Pretreatment with MCP (300mg/kg p.o.) attenuated the severity of ethanol-induced gastric mucosal damage, reductions in GUI, histopathologic aberrations, and neutrophil invasion, and PGE2 upregulation. These actions were similar to those of omeprazole, a reference anti-ulcer drug. MCP repressed gastric inflammation through the reduction of MPO, TNF-α, and IL-6, and prevented gastric oxidative stress through the inhibition of lipid peroxides with the concomitant enhancement of glutathione and catalase activity. Apoptotic markers indicated that MCP suppressed Bax and caspase-3 activity and enhanced the anti-apoptotic protein Bcl-2, which favored cell survival. MCP downregulated NF-κB and upregulated IκBα. Our study results suggested that the prophylactic administration of MCP reduced ethanol-induced gastric injury in rats through the suppression of gastric inflammation and oxidative stress, predominantly via NF-κB inhibition.
