Anti-ulcerogenic effect of ginger (rhizome of Zingiber officinale Roscoe) hydroalcoholic extract on acetic acid-induced acute colitis in rats

Spasmolytic, antioxidant, anti-inflammatory and immuno-modulatory properties of ginger (rhizome of Zingiber officinale Roscoe) suggest that it may has beneficial effects on inflammatory bowel diseases. In the present study, the effect of this herbal extract on a model of acute colitis was evaluated. Ginger hydroalcoholic extract with doses of 150, 350, 700 mg/kg, prednisolone (2 mg/kg), or vehicle were administered orally to groups of male Wistar rats (n=6) for 5 days. Other four groups received two doses of vehicle, extract (350, 700 mg/kg), or hydrocortisone acetate enema (10 mg/kg) rectally, 15 and 2 h prior to ulcer induction (2 ml of acetic acid 4% was instilled via the anus). All rats were sacrificed 24 h later and the tissue injuries were assessed macroscopically and pathologically. Extracts with all doses used were effective to reduce colon weight/length ratio similar to the reference drugs (corticosteroids). Higher oral doses of extracts (350 and 700 mg/kg) were effective to reduce ulcer severity, area and index as well as mucosal inflammation severity, extent and total colitis index compared to controls. Rectally administered extract, only at high dose (700 mg/kg) was effective to reduce ulcer index and total colitis index. It is concluded that ginger hydroalcoholic extract was effective to protect against experimental colitis, and the efficacy was greater when higher doses of extract were administered orally and in a prolonged period.