Oxidative stress and hemoglobin-cholesterol adduct in renal patients with different LDL phenotypes

Unfavorable lipid profile is a major risk factor for cardiovascular disease in renal pathology. In this study, we compared chronic renal patients and healthy controls with different LDL phenotypes (A or B) in respect of various biochemical parameters related to cardiovascular disease.

Oxidative stress and anti-oxidative defense parameters [thiobarbituric acid-reacting substances (TBARS), total oxidative status (TOS), total anti-oxidative status (TAS), total protein sulfhydryl (-SH) groups], as well as red blood cell cholesterol distribution were assessed in 40 renal patients and 40 control subjects by standardized assays. LDL particle diameters were determined by polyacrylamide gradient gel electrophoresis. LDL particles are subdivided according to their size into large LDL A phenotype (diameter >25.5 nm) and small LDL B phenotype (diameter ≤25.5 nm).

Renal patients with LDL A phenotype had increased oxidative stress (TOS: p < 0.01, and TBARS: p < 0.001) and decreased total SH- groups (p < 0.001) compared to controls with the same LDL phenotype. A notable decrease in hemoglobin-cholesterol adduct was detected in patients with LDL A phenotype (p < 0.001) and LDL B phenotype (p < 0.05) compared with appropriate controls. LDL B phenotype was characterized with increased TBARS (p < 0.05) compared with LDL A phenotype in control group.

Increased oxidative stress, decreased anti-oxidative defense followed with unfavorable changes in hemoglobin-cholesterol binding capacity, could have important influence on cardiovascular disease risk in renal patients regardless of LDL phenotype.