PTGS2 and colitis: It has been reported that potato peel extract can inhibit the production of pro-inflammatory mediators, such as nitric oxide, prostaglandin E2 (PGE2), TNF-α, and IL-6, and expression of inducible nitric oxide synthase and cyclooxygenase-2 (COX-2) protein in colonic tissue of mice with dextran sulfate sodium (DSS)-induced colitis, resulting in the prevention of colitis development [35].