MPO and colitis: Oxidative, inflammatory, and apoptotic damage may be among the causes of TNBS-induced colitis [44,45], leading to increased generation of prostaglandin E2 (PGE2) [18], increased MDA [44], NF-κB [44], MPO [46], nitric oxide synthase (iNOS) [18], and caspase-3 [44], increases of IL-1α, IL-1β, IL-4, IL-6, tumor necrosis factor (TNF)-α [17,46], and cyclooxygenase (COX)-2 [18], and decreased GSH in colon tissue [44].