Relationship of Serum Resistin Level to Traits of Metabolic Syndrome and Serum Paraoxonase 1 Activity in a Population with a Broad Range of Body Mass Index

The relationship between resistin, one of the adipokines, and metabolic syndrome is not fully elucidated. Altered activity of the HDL-associated antioxidant enzyme paraoxonase 1 (PON1) that participates in the antioxidant defense mechanisms of HDL may have an important role in the obesity-related accelerated atherosclerosis. Inverse associations of PON1 with obesity and serum levels of leptin have been demonstrated. Our aim was to investigate the association of serum levels of resistin with (i) PON1 activity, and (ii) parameters of metabolic syndrome, including some that are additional for research. A total of 74 Caucasian subjects were recruited into the study and divided into 3 age and sex-matched groups. Group 1, 25 non-diabetic overweight/ obese subjects with BMI of 28-39.9 kg/m 2 ; group 2, 25 non-diabetic obese patients with BMI ≥ 40kg/m 2 ; and the control group 3, 24 healthy, normal-weight control subjects. Serum levels of resistin were correlated negatively with BMI (r=-0.27, P<0.05), waist circumference (r= -0.28, P<0.05), serum levels of leptin (r=-0.28, P<0.05), non-esterified fatty acids (NEFA) (r= -0.23, P<0.05), and HbA 1c (r= -0.26, P<0.05), systolic BP (r= -0.28, P<0.05), and lipid peroxidation (measured by TBARS) (r= -0.40, P<0.01), and correlated positively with PON1 (r=0.24, P<0.05). No association was detected between the serum concentrations of resistin and the following investigated parameters: diastolic BP, levels of uric acid, glucose, insulin, or insulin resistance (measured by homeostasis model assessment, HOMA-IR), triglyceride, total cholesterol, LDL-C, and HDL-C. During multiple regression analyses BMI and TBARS were independent predictors of PON1, while age, gender, blood pressure, HOMA-IR, LDL-C, HDL-C, and resistin were not. Conclusions: Among the study subjects, serum levels of resistin showed a positive, although not independent correlation with serum PON1, and a negative correlation with numerous parameters of the metabolic syndrome (i.e. adiposity, blood pressure, levels of leptin, free fatty acid, glycosylated hemoglobin, and lipid peroxidation). BMI and TBARS are independent predictors of PON1 activity.