Estudos pré-clínicos do efeito gastroprotetor da mangiferina, uma glicosilxantona isolada de Mangifera indica L., em modelos experimentais de lesão gástrica aguda

Abstract

Mangiferin, a glucosylxanthone from the fruiting tree Mangifera indica Linn. (Anacardiaceae), was evaluated for the first time in acute models of gastric injury. Mangiferin (3, 10 and 30 mg/kg, p.o.) significantly attenuated (p<0,001) the gastric damage induced by ethanol (30, 35 and 63% of reduction), acidified ethanol (27, 44 and 78% of inhibition), indomethacin (22, 23 and 57% of reduction) and compound 48/80. This xanthonoid (30 mg/kg) markedly attenuated (p<0,01) the depletion of gastric mucosal non-protein sulfhydryl and the increase of malonyldialdehyde levels ethanol associated. While pretreatment with TRPV1 antagonist capsazepine (5 mg/kg, i.p.) failed to block effectively (p>0,05) the gastroprotective effect of mangiferin (30 mg/kg) against ethanol damage. Furthermore, the mangiferin effect was significantly (p<0,01) reduced in mice pretreated with indomethacin, L-NAME and glibenclamide. Mangiferin (30 mg/kg) caused significant diminutions (p<0,001) in gastric secretory volume and total acidity and significantly enhanced (p<0,001) gastric emptying in rats. Taken together, the results of this study strongly indicate a cytoprotective role for mangiferin affording gastroprotection against gastric damage induced by various ulcerogens, which is possibly mediated, in part, by endogenous prostaglandins, nitric oxide release, K+ ATP channel opening and antioxidant action.