Gastroprotective Action of Cochinchina Momordica Seed Extract Is Mediated by Activation of CGRP and Inhibition of cPLA₂/5-LOX Pathway

Cochinchina momordica seed extract (SK-MS10), which is composed of the major compounds momordica saponins, has been evaluated for its gastroprotective effects in rat models of acute gastric mucosal damage. Ethanol and water immersion restraint stress (WRS) induced gastric damage, including hemorrhages and edema, was significantly attenuated by pretreatment with SK-MS10. In addition, SK-MS10 reduced increases of mucosal myeloperoxidase (MPO), IL-1β, and TNFα levels and the expression of cPLA₂, and 5-LOX induced by ethanol or WRS. SK-MS10 also increased hexosamine, adherent mucus, and the expression of MUC5AC. Furthermore, SK-MS10 enhanced the mucosal expression of the CGRP gene and its serum levels. N G-methyl L-arginine (L-NMMA) or capsaicin desensitization reversed the SK-MS10-induced gastroprotection effect. These results suggest that SK-MS10 is a gastroprotective agent against acute gastric mucosal damage by suppressing proinflammatory cytokines, down-regulating cPLA2, 5-LOX, and increasing the synthesis of mucus. Furthermore, CGRP-NO pathway was found to play an important role in these gastroprotective effects of SK-MS10.