Malondialdehyde and nitric oxide levels in erythrocytes from patients with systemic sclerosis

To investigate malondialdehyde [MDA] and nitric oxide [NO] levels in the erythrocytes from patients with systemic sclerosis [SSc]. Twenty-nine patients diagnosed as having SSc and 16 volunteer healthy subjects [as control group] participated in the study. Fasting blood samples were obtained from the patients and healthy subjects in anticoagulated tubes [with EDTA], and the erythrocytes were separated. The MDA and NO levels were measured in the erythrocyte sediments by the spectrophotometric method. The levels of MDA and NO were elevated in the erythrocyte sediments of the patients as compared to those of the control group [1.037 +/- 0.125 vs. 0.951 +/- 0.114 micromol/g Hb, respectively, p = 0.047 for MDA, and 0.340 +/- 0.071 vs. 0.209 +/- 0.074 mmol/g Hb, respectively, p <0.001 for NO]. A weak positive correlation was also observed between MDA and NO levels [r = 0.30, p = 0.15 in the patient group, and r = 0.27, p = 0.49 in the control group]. Our results show higher levels of MDA and NO in the erythrocytes of patients with SSc than normal subjects

Oxidative stress in patients with chronic renal failure: efects of hemodialysis

To investigate blood oxidative status of patients with chronic renal failure [CRF] and possible effects of hemodialysis on the development of oxidative stress in blood. Materials and The levels of malondialdehyde [MDA] and oxidation resistance [OR] values were measured in blood plasma, erythrocyte hemolysate and erythrocyte membrane fractions of 33 patients with CRF and of 12 healthy controls. Of the 33 patients, 17 subjects were under hemodialysis treatment. MDA levels were found to be increased in all blood fractions of the patients. OR values were unchanged in erythrocyte hemolysates but decreased in plasma and erythrocyte membrane fractions of the CRF patients. Moreover, erythrocyte MDA levels were determined to be higher in hemodialyzed patients compared with both controls and non-hemodialyzed patients. OR values were lower in all blood fractions of the hemodialyzed patients relative to controls and non-hemodialyzed patients. Results suggest that there is a significant oxidative stress [expressed as peroxidation] in blood samples from patients with CRF, which is further exacerbated by hemodialysis