Endocrine Abstracts

Paraoxonase is a high-density lipoprotein-bound antioxidant enzyme that inhibits atherosclerosis. Metabolic syndrome is a combination of several metabolic abnormalities and known to be related with increased cardiovascular events. The most important component of metabolic syndrome which have impact on oxidative stress is diabetes, the most severe form of disturbed carbohydrate metabolism. The effect of metabolic syndrome on oxidative stress and paroxonase-1 (PON-1) activity has been shown be in several studies and PON-1 has been found to be related with accelerated atherogenesis. However, these studies included diabetes in metabolic syndrome. Therefore we aimed to determine the oxidative state and PON-1 activity in non-diabetic metabolic syndrome and obese patients comparing with the controls.

Thirty-three obese patients without metabolic syndrome, 43 non-diabetic, obese or over weight patients and 24 normal control subjects were enrolled in the study. All patients were performed a standard 75 g overnight glucose tolerance test. PON-1 activity, HDL-paraoxonase, arylestherase, total antioxidant status (TAS), high-sensitive C-reactive protein (CRP), lipid peroxides and metabolic parameters were analysed.

PON-1, HDL-paraoxonase and arylestherase activities were not different among the three groups, while total antioxidant status was high in both metabolic syndrome and obese groups compared with the control group (P<0.001 and P<0.05 respectively). CRP was higher in metabolic syndrome group compared with obese and the control groups (P<0.01 and P<0.001 respectively). In both obese and metabolic syndrome groups, CRP showed a positive correlation with body mass index.

In conclusion, PON-1 HDL-paraoxonase and arylestherase activities were not different in our metabolic syndrome and obese group. This finding may be due to the absence of diabetes, severely disturbed glucose metabolism.