Elevated serum concentration of cardiotoxic lipid peroxidation products in chronic renal failure in relation to severity of renal anemia.

ABSTRACT

Patients with end-stage renal disease undergoing hemodialysis (HD) are exposed to oxidative stress. Increased levels of malondialdehyde (MDA) and 4-hydroxylnonenal (HNE) were found in plasma of uremic patients indicating accelerated lipid peroxidation (LPO) as a consequence of multiple pathogenetic factors. The catabolism and action of those products was already intensively studied. As highly reactive metabolites they are able to bind to proteins, nucleic acids, and other molecules. Doing so, they exert molecular signal effects in cells and are able to exacerbate tissue and organ damage, e.g. cardiotoxic effects. Since renal anemia was shown to promote oxidative stress as well, the aim of our investigation was to examine its role in HD patients. Therefore, two groups of HD patients were investigated (group I Hb < 10 g/dl, group II Hb > 10 g/dl) and serum concentrations of MDA, HNE, and of protein carbonyls, a marker for protein oxidation, were determined. All HD patients had significantly higher levels of the LPO products MDA and HNE compared with controls. However, group I patients showed higher MDA and HNE concentrations compared to group II patients. The same result could be seen for protein carbonyls. During HD concentration of both LPO products decreased. However, this was not the case for protein carbonyls. These results lead to the conclusion that optimized correction of the renal anemia may result in a significant reduction of oxidative stress and therefore in the reduction of organ tissue damage. In this way correction of renal anemia will reduce the cardiovascular risk and comorbidity of HD patients improving their prognosis.