Plasma Retinol and Malondialdehyde Levels among Hemodialysis Patients

Background Increased oxidative stress is a well-known phenomenon in dialysis patients. Oxidative stress is viewed as a disturbance in the balance between oxidant production and antioxidant defense. Retinol, the major circulating form of vitamin A, was shown to have some antioxidant properties. Increased oxidative stress may play a role in morbidity and mortality of patients with end stage renal disease. objectiveThe aim of the study was to measure oxidative stress markers and antioxidant enzymes in hemodialysis (HD) patients, and compare these findings with those with no renal disease. MethodsThe study included 50 subjects conducted from outpatients of Nephrology and Dialysis Unit, Internal Medicine Department, Zagazig University Hospitals. Participants were enrolled after written informed consent and were divided into3 groupsGroup I (Control) 10 healthy volunteers, Group II 20 patients with chronic renal impairment on conservative treatment. Group III20 patients with ESRD for HD and blood samples were taken before the first HD session then after 3months of regular HD. Plasma retinol and malondialdehyde (MDA) levels were quantified, blood activities of catalase (CAT), superoxide dismutase (SOD) and -aminolevulinate dehydratase (ALA-D) were analysed. ResultsPlasma retinol levels and MDA were high significantly increased in HD group after dialysis compared to the patients before dialysis as regards the meanSD of plasma retinol and MDA levels, the biomarker of lipid peroxidation. Also, the SOD activity and CAT activity were high significantly increased in patients after dialysis when compared to the patients before dialysis as regards the meanSD of SOD and CAT. On the other hand, the ALA-D activity was high significantly decreased in the patients after dialysis when compared to patients before dialysis as regards the meanSD of ALA-D. Also, there was high significant positive correlation of plasma retinol with MDA, SOD and CAT in group III after HD. ConclusionThere was a significant difference in antioxidant capacity before and after hemodialysis.