OP11 - The role of paraoxonase 2 (PON2) in modulating the oxidant-antioxidant balance of the peripheral blood mononuclear cells in newly diagnosed type 2 diabetic patients

Abstract

Background Obesity is caused by chronic energy discrepancy between energy expenditure and intake. Monocytes by means of their respiratory burst (RB) are an important source of free radicals. The aim of the present study was to investigate the role of paraoxonase 2 (PON2) in the peripheral blood mononuclear cells (PBMNC) in newly diagnosed type 2 diabetic patients (NDT2D). Methods 367 NDT2D were compared regarding clinical, biochemical and oxidative stress parameters with 130 healthy subjects. All subjects were divided according to their body mass index (BMI) into overweight (BMI 25-29.9Kg/m2) and obese (BMI≥30kg/m2). The capacity of the PBMNC to release pro-oxidants and to neutralize them was determined by measuring the RB and the antioxidant enzyme PON2. Serum levels of leptin and adiponectin were determined by ELISA. For frucosamine, glutathione peroxidase (GPx) and superoxide dismutase (SOD) photometric methods were used. Results PON2 activity in PBMNC was significantly lower in NDT2D (p Conclusions The lower PON2 enzymatic activity in PBMNC is partly explained by abdominal obesity and insulin resistance. Up-regulation of monocyte PON2 activity may provide a compensatory protective mechanism against oxidative stress damage in early (prehyperglycaemic) phase of T2D. Acknowledgements This work was supported by a grant of the Romanian National Authority for Scientific Research, CNCS-UEFISCDI, project number PN-II-ID-PCE-2011-3-0429. Dr. Lixandru acknowledges the POSDRU/89/1.5/S/60746, from European Social Fund.