GASTRIC ULCER PROTECTIVE AND ANTIOXIDANT ACTIVITY OF THE LEAF ETHANOL EXTRACT OF Emilia praetermissa Milne-Redh (Asteraceae) IN RATS

Introduction: Emilia praetermissa is a plant used in African traditional medicine to treat many diseases including gastric ulcers.

Materials and Methods: Phytochemical screening of the ethanol extract of E. praetermissa was carried out, and experimental Wistar rats (140-180 g) were used to evaluate the anti-ulcerogenic effects of the leaf ethanol extract of E. praetermissa using different methods of gastric lesion induction; 1. HCl/Ethanol, 2. HCl/ Ethanol/ Indomethacin, 3. Indomethacin, 4. Absolute ethanol, 5. Cold water immersion, 6. Pylorus ligation. Sucralfate, cimetidine and omeprazole were used as reference anti-ulcer drugs. The effect of the extract on the antioxidant status of rats subjected to the cold stress was also studied.

Results and Discussion: Phytochemical screening of the leaf ethanol extract of E. praetermissa revealed the presence of phytocchemicals such as tannins, saponins, flavonoids, polysaccharides and phenols. The extract (250-750 mg/kg) dose-dependently reduced the volume and acidity of gastric secretions (41.8-35.6 mEq/L) in pylorus-ligated rats. The significant cytoprotective action of the extract (250-500 mg/kg) obtained in absolute ethanol- (62.9-83.3% inhibition), HCl/ethanol- (31.5-79.5% inhibition), pylorus ligation- (21.7-100% inhibition) and stress- (72.2-89.4% inhibition) ulcer models was accompanied in all cases by increased mucus production. Gastric cytoprotection (28.1-63.2% inhibition) dropped following pre-treatment with indomethacin. In rats subjected to cold stress, catalase activity increased while malondialdehyde concentrations dropped compared with controls. These results suggest that the leaf ethanol extract of E. praetermissa has both antisecretory and cytoprotective activity.

Conclusion: The cytoprotective action of the extract is possibly due to a combination of its ability to increase gastric mucus secretion by a mechanism similar to endogenous prostaglandins, and the gastric protective effects that are linked to the presence of anti-oxidant activities of phytochemicals.