In vitro glycoxidation alters the interactions between collagens and humanpolymorphonuclear leucocytes

Glycation and glycoxidation processes, which are increased in diabetes mell itus, are generally considered causative mechanisms of long-term complicati ons. With reference to our previous studies, type-I and -IV collagens could induce differentially the adhesion and stimulation of polymorphonuclear le ucocytes (PMNs). As PMNs play a role in sustained diabetic oxidative stress , the present study was designed to determine whether in vitro glycoxidatio n of these macromolecules could alter PMN adhesion, activation and migratio n. The adhesion of PMNs to in vitro-glycoxidized collagens was significantl y increased when compared with control collagens: + 37 % (P < 0.05) and + 9 9 % (P < 0.01) for collagens I and IV, respectively. Glycoxidized type-I co llagen increased the chemotactic properties of PMNs without significant sti mulatory effect on respiratory burst, whereas pre-incubation of PMNs with g lycoxidized type-I collagen induced a priming on subsequent stimulation by N-formyl-methionyl-leucyl-phenylalanine. Glycoxidation of type IV collagen suppressed its inhibitory effect on further PMN stimulation or migration. C ollectively, these results indicate that glycoxidation of two major extrace llular-matrix collagens considerably alters their ability to modulate PMN m igration and production of reactive oxygen species. This imbalance in PMN m etabolism may be a major event in the increased oxidative status that chara cterizes diabetes mellitus.