Influence of the disease duration on erythrocytic antioxidant defence in patients with polycythemia vera

Twelve patients with polycythemia vera (PV) were observed and assigned to two groups: group 1 had duration of the disease up to 3 years (mean duration 2.1 years); group 2 - more than 10 years (mean duration 14.6 years). 50 healthy volunteers served control. Content of haemoglobin (Hb) was determined in blood and red blood cells (RBC). Activities of superoxide dismutase (SOD), catalase (CAT), glutathione reductase (GSSG-R), glutathione peroxidase (GSH-Px), glucose-6-phosphate dehydrogenase (G-6-PD) and content of malon dialdehyde (MDA) were evaluated. It was shown that RBC in patients with PV have essential changes in their antioxidant systems (AOS). In early stage of PV (group 1) activation of SOD, CAT, GSSG-R and G-6-PD has compensating characteristics. Development of the disease (group 2) leads to weakening of AOS and activation of lipid peroxidation in membranes of RBC and to reduction of Hb level. The obtained results confirm the need for correction of AOS in RBC of patients to use natural antioxidants in the routine therapy of PV.