Ameliorative effect of ginger extract in acetic acid induced ulcerative colitis in rats

Abstract

The present study was conducted to examine the anti-inflammatory effect of ethanolic extract of ginger in acetic acid induced ulcerative colitis in rats. Forty eight Wistar rats were randomly divided into 4 equal groups; (1) Normal control group, (2) Acetic acid treated group, (3) An ethanol extract of ginger-treated group and (4) Dexamethasone-treated group. Rats were fasted for 24 h and colitis was induced in groups 2, 3 and 4 by intra-colonic administration of 4% acetic acid (2 mL). Post colitis induction, treatment was started in group 3 with ginger extract (700 mg kg-1 per day, orally) and group 4 with dexamethasone (2 mg kg-1, intraperitoneal) for 14 days. At the end of the experiment, colon samples were estimated for superoxide dismutase (SOD), catalase (CAT), reduced glutathione (GSH) and glutathione peroxidase (GPx), thiobarbituric acid reacting substance (TBARS) and Protein Carbonyls (PC). Inflammatory and anti-inflammatory cytokines viz.,Tumor necrosis factor-alpha (TNF- α), interleukin-1 β (IL-1 β) and interleukin-10 (IL-10) and prostaglandins E2 level (PGE2) was estimated in the colon and a portion of colon samples were snap-frozen for histopathological studies. Results revealed that treatment groups significantly (p<0.05) attenuated the increased colonic TBARS, PC, TNF-α, IL-1β and PGE2 levels and significantly (p<0.05) increased the SOD, CAT, GSH, GPx and IL-10 levels. Histopathological examinations revealed reduced haemorrhage and oedema of the colon in the treatment groups. The study suggests that ginger extract significantly attenuated the acetic acid induced inflammation and histopathological changes may be through its scavenging effect on oxygen-derived free radicals.