Prophylactic and Healing Activities of the Leaves Aqueous Extract of Eremomastax speciosa on Gastric Ulcers in Rats

Aims: Information provided by practitioners of Cameroonian ethnomedicine suggested that Eremomastax speciosa (E. speciosa) possesses antiulcer activity. This led us to evaluate the prophylactic and healing effects of this plant.

Place and Duration of Study: Department of Animal Biology & Physiology (Animal Physiology Laboratory) and Department of Organic Chemistry (Laboratory of Medicinal Chemistry), Faculty of Science, University of Yaoundé I, between May 2012 and November 2013.

Materials and Methods: The anti-ulcer activity of the leaf aqueous extract of E. speciosa was tested in rat using several acute gastric ulcer-inducing methods (HCl/ethanol, indomethacin-HCl/ethanol, indomethacin, absolute ethanol and cold/restraint stress). The healing effect on chronic acetic acid-induced gastric ulcers was also tested.

Results: Oral administration of the extract of E. speciosa prevented the formation of acute gastric lesions induced by different necrotizing agents. The inhibition was complete (100% inhibition) at the dose of 200 and 400 mg/kg of extract for the HCl/ethanol and cold/restraint stress methods, respectively. Pre-treatment with indomethacin significantly reduced the ability of the extract to inhibit the formation of HCl/ethanol induced lesions, with inhibition dropping to 39.63% for the dose 200 mg/kg. The lowest degree of gastric protection by the extract (12.13 to 13.80%) was obtained when indomethacin was administered alone by oral route. The protective effect of the extract (200 mg/kg) was reduced significantly when absolute ethanol (27.84% inhibition) was used as the necrotizing agent compared with the HCl/ethanol solution (100%). The prophylactic actions were associated with significant increases in gastric mucus production. The healing rate of chronic acetic acid-induced ulcers was 55.40 and 77.70%, for the dose 200 and 400 mg/kg of extract, respectively.

Conclusion: The prophylactic anti-ulcer effects of the extract are associated with enhanced mucus production which is an important factor in the mechanism of the healing process of chronic gastric ulcers.