EFFECTS OF HOMOPTEROCARPIN ON THE ANTI-ULCEROGENIC PROPERTIES OF AFRICAN ROSEWOOD (Pterocarpus erinaceus)

Abstract

Gastric ulcer is a discontinuity in the gastric mucosa that occurs due to imbalance between gastric mucosal protective factors and aggressive factors. Pterocarpus erinaceus stem-bark extract is employed locally in the Southwest part of Nigeria to treat gastric ulcer. This study phytochemically screened and investigated the anti-ulcerogenic properties of ethanolic stem-bark extract of Pterocarpus erinaceus and homopterocarpin (an isoflavonoid from Pterocarpus erinaceus) on different ulcer models in albino rats with a view to check its protective effect. Ulcer was induced using four ulcer models namely; ethanol (5ml/kg), indomethacin (25mg/kg), aspirin (200mg/kg), cold stress (40C). Sixty male rats weighing between 150-200g were randomly distributed into five groups. Group I (control) received olive oil (1ml/kg) as the vehicle, group II was administered with the various induction drugs, group III was adminsitered orally 100mg/kg of cimetidine (prior of induction), group IV received orally 25mg/kg of homopterocarpin prior to induction while group V was administered 100mg/kg of ethanolic stem bark extract of Pterocarpus erinaceus (prior to induction). Ulcer indices, pH and volume of gastric juice, acid concentration of gastric juice, macroscopic view of the stomachs, mucus concentration, malonaldehyde (MDA) levels, reduced gluthathione (GSH) levels, superoxide dismutase (SOD) activity and total protein of the stomach tissue were estimated. The results revealed that all the drugs models caused significant increase in the ulcer indices, acid concentration of gastric juice, volume of gastric juice as compared with the control. However, there were decreases in pH of the gastric juice and mucus concentrations of the stomach tissues as compared to the control. The induction of ulcer caused significant increases in gastric MDA and decrease in reduced gluthatione, superoxide dismutase and total protein as compared to the control. Ethanolic stem-bark extract of Pterocarpus erinaceus, homopterocarpin and cimetidine caused a reversal of the effects of ulcer induction on these parameters as compared to control. Pterocarpus erinaceus was found to be more potent at the dosage used than homopterocarpin. The protection offered by the ethanolic extract and the homopterocarpin compared well with that of the standard drug (cimetidine). In conclusion, the study revealed that the presence of homopterocarpin and other bioacative compounds in Pterocarpus erinaceus contributed to the anti-ulcerogenic potentials of ethanolic stem-bark extract of Pterocarpus erinaceus. The study has equally shown that antioxidative, antisecretory and acid neutralizing effect, may be some of the mechanisms of its anti-ulcerogenic activity.