The role of reactive oxygen metabolites in the pathogenesis of ulcerative colitis: a speculative synthesis

The lesson learned from the studies on oxygen-derived free radicals and several well recognized metabolic and morphologic disturbances associated with IBD and intestinal ischaemia strongly suggests that oxyradicals can be an important mediators of colonic injury in UC. Instead of summarizing of what has been said, a schematic illustration of different pathogenetic factors which can way a vicious circle of destruction is proposed. Unfortunately, a new and specific therapy of UC is as yet not available, because the locus of primary lesion is poorly understood. It is, however, reasonable to search for a complex therapy which could break a chain of pathological processes at several subunits functioning in either positive or negative feed-back loops. In my belief, complementary treatment with free-radical scavengers is to be tested as a new and potentially efficacious modality. In this respect, preliminary encouraging results obtained with local administration of SOD encapsulated in liposomes deserve attention.