Effect of ciprofibrate on lipoprotein metabolism and oxidative stress parameters in patients with type 2 diabetes mellitus and atherogenic lipoprotein phenotype

Abstract

The effect of ciprofibrate therapy on plasma lipids and lipoproteins, HDL and LDL subfraction profile, fractional esterification rate of HDL cholesterol (FER_HDL) and the resistance of LDL and serum lipids to oxidation was studied in 24 males with type 2 diabetes and atherogenic lipoprotein phenotype (ALP). We also examined the effect of ciprofibrate therapy on oxidative DNA damage in peripheral lymphocytes. No differences in glucose, HbA1C and BMI levels were found after three months of ciprofibrate therapy. Ciprofibrate significantly decreased total cholesterol and triglyceride levels by 5.5% and 50% (p = 0.05; 0.001, respectively) and increased HDL-cholesterol levels by 8.5% (p = 0.05). FER_HDL and LDL subfraction profile were also favorably affected, However, no effect on HDL subclasses was found. There were no statistically significant differences in lipid resistance to oxidation measured in serum and in LDL (lag time and V_max) before and after therapy. No significant effect of ciprofibrate was found on oxidative DNA damage. The evaluation of the relationship between oxidative damage purines with lag time in LDL and maximal rate of serum lipid oxidation showed significant correlations after therapy (r = −0.58; 0.47, p = 0.01; 0.05, respectively), but only trends before starting ciprofibrate treatment. Type 2 diabetes mellitus represents a complex metabolic disorder expressed in glucose and lipoprotein disturbances and increased oxidative stress. Ciprofibrate therapy favorably affected major features of lipid abnormalities of diabetic patients, but the level of oxidative stress assessed by in vitro and in vivo methods was not changed. The evaluation of expected logical correlations between the parameters of lipoprotein metabolism, lipid resistance in serum and LDL, and oxidative DNA damage showed that those correlations were more relevant and significant after ciprofibrate treatment and were not related with glucose homeostasis.