Altered Activities of Antioxidant Enzymes in Patients with Metabolic Syndrome

Abstract

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.

Effects of telmisartan and linagliptin when used in combination on blood pressure and oxidative stress in rats with 2-kidney-1-clip hypertension

“…Oxidative stress is known to be increased in patients with metabolic syndrome [12] and hypertension [46]. Reports on a correlation between increased plasma levels of carbonyl proteins and SBP in patients with essential hypertension [50] correspond to our result (Fig.…”

“…Hence, the levels of protein carbonyls and oxLDL reflect, respectively, the level of total protein oxidation and lipid peroxidation. Oxidative stress is increased in patients with metabolic syndrome [12] and implicated in chronic cardiovascular diseases including hypertension [13,14]. A relationship has been proposed between markers of oxidative stress and development of renal and cardiac fibrosis that is independent of elevated BP per se [15][16][17].…”

Assessment of the redox status in patients with metabolic syndrome and type 2 diabetes reveals great variations

“…The significantly lower GSH levels in the erythrocytes of the patients with MetS and T2D compared with the controls also supported the induction of oxidative stress in the patients with MetS and T2D. Another study also reported decreased GSH levels in patients with MetS ( 40 ). Likewise, a decrease in GSH levels in human erythrocytes and serum has been demonstrated in other studies on patients with T2D ( 41 – 43 ).…”

Mitochondrial free radical theory of aging: Who moved my premise?

“…vitamin C, vitamin E and glutathione) that scavenge free radicals and inhibit generation of ROS . Whereas in a pathological state where ROS cannot be swept off, oxidative stress will accumulate and cells will malfunction, which eventually triggers the switch of aging …”

“…5 Whereas in a pathological state where ROS cannot be swept off, oxidative stress will accumulate and cells will malfunction, which eventually triggers the switch of aging. 6,7 Evidence in line with this theory includes: (i) that there exists a positive correlation between chronological age and the level of ROS production 8,9 (i.e. older animals tend to suffer more from ROS damage than their younger counterparts and long-lived species leak less ROS from the ETC than short-lived ones); (ii) that mitochondrial deficiency is observed in several agerelated diseases and during the process of aging; [10][11][12] and (iii) that some anti-oxidants have a positive effect in enhancing mitochondrial function and extending lifespan.…”