The Investigation of Relationship Between Secondary Hyperparathyroidism and Oxidative Stress in Patients with Chronic Kidney Disease

OBJECTIVES: Our aim was to investigate the changes of the oxidant and antioxidant systems in chronic kidney disease patients who had increased parathyroid hormone (PTH) levels in the present study. PATIENTS and METHODS: A total of fifty hemodialysis patients were divided into two equal groups based on the PTH levels; > 300 pg/mL (Group 1) and < 300 pg/mL (Group 2). A total 20 healthy subjects were included in the study as the control group (Group 3). The measurement of malondialdehyde (MDA), advanced protein oxidation products level (AOPP), ascorbic acid (AA) levels, and activities of myeloperoxidase (MPO) and catalase (CAT) were performed by colorimetric methods. PTH measurement was also performed by chemiluminescent method. RESULTS: As compared with control group, MDA level was significantly higher in Groups 1 and 2 (p<0.05), and the AOPP level was higher in Group 2 (p<0.05) only. The MPO activity was significantly lower in Group 1 as compared to the control group (p<0.05). The CAT activity and AA levels were significantly lower in Groups 1 and 2 than in the control group (p<0.05). CONCLUSIONS: This study has shown that patients with chronic kidney disease are characterized by increased oxidative stress and decreased antioxidant defense systems. However, increased PTH levels did not have an additional effect on the oxidant and antioxidant mechanisms in these patients.