RESUMO

BACKGROUND: The last decade has been marked by increasing data regarding gastroinstestinal diseases, specially gastritis and ulcer. In order to prevent or treat these diseases, many studies have demonstrated the potential of medicinal plants. The aim of this study was to evaluate the phytochemical profile and the gastroprotective activity of the methanolic extract of Myrcianthes pungens whole fruit, peel, pulp, seeds, and leaves. METHODS: The methanolic extracts were analyzed by thin layer chromatography (TLC) to detect the presence of phenolic compounds by direct comparison with an authentic sample. To evaluate the gastroprotective activity, two experimental models were used: acute ulcer model induced by ethanol/HCl and acute ulcer model induced by nonsteroidal anti-inflammatory drug (indomethacin). Animals were divided in different groups (n= 6) and pretreated orally with the methanolic extracts of M. pungens at doses of 50, 125, and 250 mg/kg, the positive control (cimetidine 100 mg/kg) and negative control (distilled water).RESULTS: The TLC analysis indicated the presence of the flavonoids quercetin and quercitrin in the leaves, quercetinin the peel, and catechin and epicatechin in the leaves and seeds of M. pungens. The extracts of leaves, peel, and pulp showed significant gastroprotective potential regarding the relative area of the lesion observed only in acute ulcer model induced by ethanol. The extracts of whole fruit, peel, pulp, seeds, and leaves showed significant gastroprotective potential observed in acute ulcer induced by indomethacin model. CONCLUSIONS: The gastroprotective activity can be related with the presence of some phenolic compounds identified in phytochemical analysis.

Assuntos

Animais , Feminino , Ratos , Avaliação Pré-Clínica de Medicamentos , Plantas Medicinais/química , Gastropatias , Flavonoides

RESUMO

This study evaluated the gastroprotective value of the methanol extracts from fruits of Morus nigra L. (black mulberry (MEMN)) and Rubus niveus Thunb (raspberry (MERN)). The total phenolic compounds and flavonoids were measured, as well as the in vitro 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical scavenger activity. The gastroprotective effects of the extracts against 60% ethanol/0.3 M HCl were evaluated in mice. After that, the lipid hydroperoxides and reduced glutathione levels at ulcerated tissue were determined. The effects of extracts on H+/K+-ATPase activity were also verified. The extracts exhibited high contents of polyphenols; however, MERN presented 1.5-fold higher levels. The presence of flavonoids also was confirmed. In addition, MEMN (IC50 = 13.74 µg/mL) and MERN (IC50 = 14.97 µg/mL) scavenged DPPH radical. The MEMN reduced the ulcer area only at 300 mg/kg (p.o.) by 64.06%. Interestingly, MERN decreased the ulcer area in a superior potency (ED50 = 20.88 mg/kg), reducing the ulcer area by 81.86% at 300 mg/kg, and increased the gastric mucin levels. The antioxidant effects of extracts were evidenced by reduced lipoperoxides and increased reduction of glutathione amount in the gastric mucosa. However, MEMN or MERN did not change the H+/K+-ATPase activity. These results confirm that M. nigra and R. niveus are berries with a gastroprotective value by strengthening of gastric protective factors.