Altered Activities of Antioxidant Enzymes in Patients with Metabolic Syndrome

OBJECTIVE In the pathogenesis of the metabolic syndrome (MetS), an increase of oxidative stress could play an important role which is closely linked with insulin resistance, endothelial dysfunction, and chronic inflammation. The aim of our study was to assess several parameters of the antioxidant status in MetS. METHODS 40 subjects with MetS and 40 age- and sex-matched volunteers without MetS were examined for activities of superoxide dismutase (CuZnSOD), catalase (CAT), glutathione peroxidase 1 (GPX1), glutathione reductase (GR), paraoxonase1 (PON1), concentrations of reduced glutathione (GSH), and conjugated dienes in low-density lipoprotein (CD-LDL). RESULTS Subjects with MetS had higher activities of CuZnSOD (p < 0.05) and GR (p < 0.001), higher concentrations of CD-LDL (p < 0.001), lower activities of CAT (p < 0.05) and PON1 (p < 0.05), and lower concentrations of GSH (p < 0.05), as compared with controls. Activity of GPX1 was not significantly changed. CONCLUSIONS Our results implicated an increased oxidative stress in MetS and a decreased antioxidative defense that correlated with some laboratory (triglycerides, high-density lipoprotein cholesterol (HDL-C)) and clinical (waist circumference, blood pressure) components of MetS.