Role of Mucus Secretion and Sulfhydryl Groups in Gastroprotection Mediated by a Flavonoid Fraction of Bidens aurea

Abstract

The aerial parts of Bidens aurea (Aiton) Sherff have been used in folk medicine as an antiulcer agent. The efficacy of an ether extract to prevent gastric mucosal damage produced by several necrotic agents was studied in rats. The best efficiency was against lesions induced by 30% NaCl with a significant decrease of damage at all doses tested (250, 125 and 62.5 mg kg-1). In contrast, only the highest dose (250 mg kg-1) was effective on gastric erosions induced by 0.6 ɴ HCl. This effect could not be related with the mucus gel production only since the groups treated with of absolute ethanol or 30% NaCl before and then received 250 mg kg-1 of the ether extract increased significantly the amount of gastric mucus and its glycoprotein content. However, the ether extract of Bidens aurea enhanced the production of mucosal non-protein SH groups at all doses assayed after treatment with absolute ethanol and 0.6 ɴ HCl. With NaCl-induced gastric injury, also the highest dose (250 mg kg-1) produced an increase of this parameter. The results suggest that a slight augmentation of the mucus gel concentration and the increase of non-protein sulfhydryl compounds, could con­ tribute to the functional protection mechanism mediated by a flavonoid fraction of B.aurea in these experimental models.

Effects of aqueous extracts fromQuercus ilex l. root bark,Punica granatum l. fruit peel andArtemisia herba-alba Asso leaves on ethanol-induced gastric damage in rats

“…The observed protection was independent of the polyphenol concentration in the test solutions, but seemed to depend on the nature of the compounds present in the extracts. Several reports have shown that flavonoids (flavones, flavanones, aurones, chalcones) exert protective effects against experimentally induced lesions of the stomach (Parmar and Ghosh, 1981;Konturek et al, 1986;Murakami et al, 1991;Motilva et al, 1992;Di Carlo et al, 1994;Alarcon De La Lastra et al, 1994a-c;Ares et al, 1995;La Casa et al, 1995;Alarcon De La Lastra et al, 1995). The results obtained with tannic acid are not in agreement with those of Hung and Lee (1991).…”