Purification of Gastroprotective Triterpenoids from the Stem Bark ofAmphipterygium adstringens; Role of Prostaglandins, Sulfhydryls, Nitric Oxide and Capsaicin-Sensitive Neurons

Publisher Website
Google Scholar
Abstract
In this investigation three bioactive compounds, responsible for the gastroprotective property of Amphipterygium adstringens, were purified from an active dichloromethane fraction. These compounds were 3α-hydroxymasticadienonic acid, β-sitosterol and 3-epi-oleanolic acid. The latter was the most active compound (88.8 % of gastroprotection) followed by 3α-hydroxymasticadienoic acid and β-sitosterol (69.8 and 42.5 % of gastroprotection, respectively). Carbenoxolone was used as positive control and it showed 88.4 % of gastroprotection. Masticadienonic acid was also isolated from the active fraction, but it was unable to inhibit the ethanol-induced gastric lesions. The gastroprotection of the methanol extract was completely inhibited by the pretreatment with l-NAME and attenuated by pretreatment with indomethacin and N-ethylmaleimide. These results suggest that endogenous nitric oxide plays an important role in the gastroprotection of A. adstringens methanol extract on ethanol-induced gastric mucosal lesions and that there is partial participation by prostaglandins and endogenous sulfhydryls. The effect of 3α-hydroxymasticadienonic acid was attenuated only by pretreatment with N-ethylmaleimide, indicating that endogenous sulfhydryls (thiols) participate in its gastroprotective mechanism. Capsaicin-sensitive afferent neurons do not participate in the gastroprotection of either the methanol extract or 3α-hydroxymasticadienoic acid.

This publication has 0 references indexed in Scilit: