Effect of methanolic extract of Pongamia pinnata Linn seed on gastro-duodenal ulceration and mucosal offensive and defensive factors in rats

Pongamia pinnata has been advocated in Ayurveda for the treatment of various inflammatory conditions and dyspepsia. The present work includes initial phytochemical screening and study of ulcer protective and healing effects of methanolic extract of seeds of P. pinnata (PPSM) in rats. Phytochemical tests indicated the presence of flavonoids in PPSM. PPSM when administered orally (po) showed dose-dependent (12.5-50 mg/kg for 5 days) ulcer protective effects against gastric ulcer induced by 2 h cold restraint stress. Optimal effective dose of PPSM (25 mg/kg) showed antiulcerogenic activity against acute gastric ulcers (GU) induced by pylorus ligation and aspirin and duodenal ulcer induced by cysteamine but not against ethanol-induced GU. It healed chronic gastric ulcer induced by acetic acid when given for 5 and 10 days. Further, its effects were studied on various parameters of gastric offensive acid-pepsin secretion, lipid peroxidation (LPO) and nitric oxide (NO) and defensive mucosal factors like mucin secretion and mucosal cell shedding, glycoproteins, proliferation and antioxidants; catalase (CAT), superoxide dismutase (SOD) and glutathione (GSH) levels. PPSM tended to decrease acid output and increased mucin secretion and mucosal glycoproteins, while it decreased gastric mucosal cell shedding without any effect on cell proliferation. PPSM significantly reversed the increase in gastric mucosal LPO, NO and SOD levels caused by CRS near to the normal level while it tended to increase CAT and GSH level decreased by CRS and ethanol respectively. Thus, the ulcer protective effects of PPSM may be attributed to the presence of flavonoids and the actions may be due to its effects both on mucosal offensive and defensive factors.