Fenofibrate treatment reduces circulating conjugated diene level and increases glutathione peroxidase activity

Treatment with fibrates showed benefit in randomized trials predominantly in subgroups of patients with dyslipidaemia of metabolic syndrome. Post hoc analyses of these trials show that the effect of fibrates on lipid levels explains only minor part of the treatment benefit. The aim of the present study was to examine effect of fenofibrate on some parameters of oxidative stress. The study group included 20 patients (6 males, 14 females) with combined dyslipidaemia. The average age was 54 ± 10 years. Fenofibrate was given for 8 weeks in the dose of 300 mg daily. Lipid levels and parameters of oxidative stress were measured at baseline and after treatment period. Treatment with fenofibrate led to reduction of total cholesterol by 18%, LDL cholesterol and apoB by 17%, triglycerides by 46%, as well as increase of HDL cholesterol level by 10%. Among the measured parameters of oxidative stress, fenofibrate treatment significantly reduced level of circulating conjugated dienes (CD) in average by 42% ( p < 0.0001) and also non-significantly reduced the production of malonaldehyde. Fenofibrate treatment led to an increase of the activity of antioxidant enzyme glutathione peroxidase (GPx) by 80% from baseline values ( p = 0.001). Treatment with fenofibrate significantly reduced the level of conjugated dienes, a measure of LDL oxidation, and increased GPx activity. This finding could at least partially explain beneficial effect of fenofibrate treatment beyond that related to levels of commonly measured lipid parameters.