Role of oxidized low-density lipoprotein in the atherosclerosis of uremia.

Lipoprotein oxidation is involved in the genesis of atherosclerosis. In chronic renal failure (CRF), oxidative stress is enhanced because of an imbalance between pro-oxidant and antioxidant systems. Oxidative modifications of low-density lipoproteins (LDLs) occur not only at the level of lipid moiety, but also of protein moiety. We have shown that oxidation of LDL by hypochlorous acid (HOCl) in vitro, reflecting increased myeloperoxidase activity in vivo, leads to modifications of apoliproteins such that the latter in turn are capable of triggering macrophage nicotinamide adenine dinucleotide phosphate-oxidase activation. These oxidative changes of LDL protein moiety, if shown to occur to a significant extent in uremic patients in vivo, may represent an important alternative pathway in the pathogenesis of atheromatous lesions.