Role of the COX-independent pathways in the ulcer-healing action of epigallocatechin gallate.

The modulation of the cyclooxygenase-independent pathway by the green tea-derived polyphenol, epigallocatechin gallate (EGCG) during its healing action against indomethacin (IND)-induced stomach ulceration in mice was investigated. On the 3rd day of its administration, IND (18 mg kg(-1)) induced maximum stomach ulceration which was associated with increased myeloperoxidase (MPO) activity (2.1-fold, p < 0.001), and inducible nitric oxide synthase (iNOS) expression (2.5-fold, p < 0.001), along with augmented levels of serum nitrite (1.3-fold, p < 0.001), selectins and cell adhesion molecules (CAMs), as well as reduced endothelial nitric oxide synthase (eNOS) expression (53%, p < 0.001). Treatment with EGCG (2 mg kg(-1)) and omeprazole (3 mg kg(-1)) for 3 days reversed these parameters, and provided excellent (76-77%) ulcer healing.