THE ROLE OF HEMOGLOBIN DERIVED HEME IN THE PATHOGENESIS OF VASCULAR DISORDERS

In the pathogenesis of several vascular disorder modified proteins and lipids generated by reactive oxygen species accumulate in the vessel wall resulted in atherosclerosis, calcification, neovascularization. Since transition metals are also accumulating in these pathologies, generating continuous free radical stress. We suggested that the source of iron is heme derived from modified hemoglobin. Using in vitro cell culture models and human vessel samples, we proved, that heme is an efficient free radical catalyst, toxic for cell membranes and lipoproteins leading to vessel injury. Next we tested several heme proteins as potential origins for heme. We proved that the main heme donor is the modified hemoglobin after red blood cell hemolysis. Hemoglobin is not only heme donor, but the modified globin also plays a role in vessel pathologies. We do not know yet whether glycation of hemoglobin has an effect on hemeprotein mediated vessel wall injury.