Influence of cardiac resynchronization therapy on oxidative stress markers in patients with chronic heart failure.

BACKGROUND: The aim of the study was to assess changes of substances of oxidative stress in patients treated with cardiac resynchronization therapy (CRT). METHODS: The study comprised 51 patients with median age of 66 years. The presence, severity, and changes of oxidative stress during CRT were assessed and expressed as malondialdehyde (MDA) concentration in plasma or in red blood cells. Antioxidant activity was assessed by the activity of catalase (CAT), superoxide dismutase (SOD) and glutathione peroxidase (GPx) in red blood cells. The concentration and activities were analyzed directly prior to implantation, 2-5 days after the procedure and after 6 months. Follow-up (6 months) included clinical, echocardiographic and implanted device assessments. RESULTS: During the follow-up, 14% patients died. The median percentage of biventricular pacing was 99.29%. After 6 months 88% of patients improved NYHA, 12% remained as non-responders. Left ventricular ejection fraction increased from median 21.5% to 29% (p < 0.05). Left ventricular end-diastolic diameter decreased significantly from a median of 69.5 mm to 63 mm (p < 0.05). After a 6-month study, MDA plasma concentration and the activity levels of each antioxidant enzymes (CAT, SOD, GPx) showed a statistically significant reduction (p < 0.05). Changes concerning MDA concentrations in red blood cells remained statistically insignificant. CONCLUSIONS: Resynchronization effect oxidative stress by reducing plasma concentration of MDA, CAT, SOD and GPX.

Oxidant-antioxidant balance in patients with psoriasis.

BACKGROUND: Psoriasis is a chronic inflammatory skin disease characterized by pathological skin lesions due to various exogenous and endogenous factors and associated with a number of biochemical and immunological disturbances. Antioxidant enzymes may be involved in the pathogenesis of the disease. The aim of this study was to evaluate the concentration of lipid peroxidation products and glutathione peroxidase (GPx) activity in the blood of patients with psoriasis before and after treatment by conventional methods. MATERIAL/METHODS: The patient group consisted of 67 persons with psoriasis vulgaris who were treated at the Department and Clinic of Dermatology. The duration of the disease was from 3 to 34 years. All patients were treated topically. The concentration of thiobarbituric acid reactive substances (TBARS) was determined in the blood plasma. The activity of GPx was determined in erythrocytes. RESULTS: In the healthy persons, GPx activity was 16.8+/-3.7 U/g Hb and TBARS concentration 0.63+/-0.16 nmol MDA/ml of plasma. In the psoriasis patients, GPx activity in erythrocytes was 14.8+/-4.3 U/g Hb and TBARS concentration was 0.73+/-0.22 nmol MDA/ml of plasma before treatment. The applied external treatment caused improvement in the clinical state and a slow increase in GPx activity as well as a decrease in TBARS concentration to values comparable to those of the healthy volunteers. CONCLUSIONS: The results suggest that disorders in antioxidant defense mechanisms may play an important role in the pathogenesis of psoriasis.