DOES LONG-TERM TREATMENT OF RENAL ANEMIA WITH RECOMBINANT ERYTHROPOIETIN INFLUENCE OXIDATIVE STRESS IN HEMODIALYZED PATIENTS

Background. Patients with end-stage renal failure undergoing haemodial ysis (HD) are exposed to oxidative stress. Increased levels of malondi aldehyde (MDA) were demonstrated in plasma of uraemic patients, indica ting accelerated lipid peroxidation (LPO) as a consequence of multiple pathogenetic factors. The aim of our investigation was to examine the role of renal anaemia in oxidative stress in HD patients. Methods. MD A and 4-hydroxynonenal (HNE) were measured in three groups of patients undergoing HD: group I comprised eight patients with a blood haemoglo bin (Hb) < 10 g/dl (mean Hb = 8.1 +/- 1.3 g/dl), and group II were eig ht patients with a Hb >10 g/dl (mean Hb = 12.4 +/- 1.9 g/dl); none of these 16 patients had been treated with human recombinant erythropoiet in (rHuEpo). Group III comprised 27 patients with a mean Hb of 10.5 +/ - 1.6 g/dl after long-term rHuEpo treatment. Results. Mean plasma conc entrations of both MDA and HNE were significantly higher (P<0.0001) in all 43 HD patients than in 20 healthy controls (MDA 2.85 +/- 0.25 vs 0.37 +/- 0.03 mu M, HNE 0.32 +/- 0.03 vs 0.10 +/- 0.01 mu M). Comparin g the three groups, it was shown that KD patients with a Kb <10 g/dl h ad significantly higher plasma levels of LPO products (MDA 3.81 +/- 0. 86 mu M, HNE 0.45 +/- 0.07 mu M) than KD patients with a Hb > 10 g/dl (MDA 2.77 +/- 0.58 mu M, HNE 0.25 +/- 0.05 mu M), and than HD patients treated with rHuEpo (MDA 2.50 +/- 0.12 mu M, HNE 0.29 +/- 0.03 mu M). Furthermore, an inverse correlation between plasma concentration of L PO products and haemoglobin levels was seen (r = 0.62, P<0.0001). Conc lusion. Radical generation in PID patients might be caused in part by renal anemia itself. Treatment with rHuEpo may decrease radical genera tion effectively in HD patients due to the increase in the number of r ed blood cells and blood haemoglobin concentration.