Background: Curcumin is claimed as a potent protectant against gastric ulcer (GU) induced by strong necrotizing agents including NSAIDs through its antioxidant, anti-inflammatory and gastroprotective activities. However, it was found to exert opposite effects to either delay ulcer healing or exacerbate ulcer inflammation through some curative mechanisms differently modified by curcumin dosage. Its ability in inhibiting the expression of COX-2 may also delay the healing of NSAIDs-induced GU. Recently, a topical chitosan-curcumin solution has been found to be a safe and potential alternative agent in treating oral ulcer. Therefore, an oral chitosan-curcumin mixture was developed and determined for its efficacy in treating NSAIDs-induced GU in rat.
Methods: A chitosan (150 mg)-curcumin (20 mg) mixture with optimal gastric pH was developed. Indomethacin (30 mg/kg) was given orally to the rat and test preparations were administered orally at 5 h later and then every 24 h for two consecutive days. The sum of all gastric ulcerated areas (mm2) for each stomach was used as ulcer index. Gastric pro-inflammatory mediators and cytoprotective factors were determined.
Results: An oral administration of a chitosan-curcumin mixture exerted a superior efficacy than curcumin, chitosan or lansoprazole (a standard antiulcer agent) in healing indomethacin-induced GU. It was revealed that the mixture exhibited the highest anti-oxidant, anti-inflammatory and gastric mucus producing activities including the high potency in down-regulating pro-inflammatory COX-2 and iNOS expression but up-regulating cytoprotective COX-1, nNOS and eNOS expression.
Conclusion: The present findings indicated the benefit of a chitosan-curcumin mixture as a potential alternative agent in treating NSAIDs-induced gastric ulcer.