Childhood obesity is a predisposing factor for adult cardiovascular diseases. Human serum paraoxonase (PON1) may protect against atherosclerosis by hydrolyzing lipid peroxides in oxidized LDL. Alterations and potential correlations of PON1 activities, leptin and adiponectin levels in childhood obesity were studied. We measured PON1 paraoxonase and arylesterase activities, anthropometric parameters, leptin and adiponectin levels in 59 white, obese (obese group-OB: BMI corrected for age: 95.1 Ϯ 3.5 percentile, age: 11.9 Ϯ 1.6 y) and 51 normal-weight children (control group-C: BMI corrected for age: 64.1 Ϯ 8.4 percentile, age: 12.0 Ϯ 3.9 y ng/mL; p Ͻ 0.0001) and lower adiponectin levels (OB: 7.56 (5.69/12.06) g/mL versus. C: 11.51 (8.84/14.49) g/mL; p Ͻ 0.001) compared with the normal-weight group. PON1 arylesterase activity showed inverse univariate correlation with leptin (r ϭ Ϫ0.29; p Ͻ 0.05) and positive correlation with adiponectin levels (r ϭ 0.39; p Ͻ 0.01). In multiple regression analysis adiponectin was strongly associated with PON1 arylesterase activity in obese children (␤ ϭ 0.45, p Ͻ 0.02). Our results emphasize the importance of the investigated metabolic alterations which may have further effects on cardiovascular morbidity and mortality in later adulthood. Altered levels of leptin, adiponectin and PON1 activities may be useful markers beside the general risk factors in childhood obesity.

Obesity as a pathogenic disorder is a predisposing factor for cardiovascular diseases and shows an increasing incidence in the industrialized countries. Adipokines such as leptin, adiponectin and resistin have a great impact on the development of atherosclerosis in obesity. Elevated levels of leptin have been found to be atherogenic whereas decreased levels of adiponectin have been proved to be anti-atherogenic in recent studies. The exact role of resistin in the process of atherosclerosis has so far remained uncertain and controversial. In our recent work, we studied the alteration in human paraoxonase-1 (PON1) activity and adipokine levels; furthermore, we also aimed at identifying the potential correlation between these parameters in this metabolic disorder. We investigated the abovementioned parameters both in adults and in children, with regard to the emerging role of childhood obesity and to get a clearer view of these factors during a whole lifetime. Investigating the adult population with a broad range of body mass index (BMI) we found significantly increased leptin and significantly decreased adiponectin and resistin levels and PON1 activity in the obese group compared to the lean controls. Adiponectin and resistin levels showed significantly positive correlation, while leptin and BMI showed significantly negative correlation with PON1 activity.Our findings were similar in childhood obesity: leptin showed significantly negative correlation, while adiponectin showed significantly positive correlation with PON1 activity. We found gender differences in the univariate correlations of leptin and adiponectin levels with PON1 activity in the adult population. In multiple regression analysis, adiponectin proved to be an independent factor of PON1 activity both in childhood and adult obesity, furthermore thiobarbituric acid-reactive substances (TBARS) also proved to be an independent predictor of the enzyme in adults, reflecting the important role of oxidative stress in obesity. Investigating PON 192 Q/R polymorphism by phenotypic distribution (A/B isoenzyme) in obese children, we found a significant correlation of PON1 arylesterase activity with leptin and adiponectin levels, and of body fat percentage with PON1 192 B isoenzyme.According to our studies, these metabolic changes in obesity predispose to the early development of atherosclerosis throughout our whole lifetime. Decreased activity of PON1 and alterations in adipokine levels in childhood obesity could contribute to an early commencement of this process, detected only later in adulthood by increased cardiovascular morbidity and mortality. Changed levels of leptin, adiponectin, resistin and PON1 activity at all ages, just like 192 Q/R polymorphism determined by phenotypic distribution, may be useful markers beside the general risk factors.Keywords (separated by '-') Adipokines -Leptin -Adiponectin -Resistin -Obesity -Paraoxonase-1 -Childhood Abstract Obesity as a pathogenic disorder is a predisposing factor for cardiovascular diseases and shows a...

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Our investigation suggests that modifications in dietary habits and physical activity induce antiatherogenic changes in childhood obesity. These findings emphasize the major role of primary prevention and nonpharmaceutical treatment of childhood obesity through lifestyle changes based on diet and increased physical activity.

High TG and low HDL-C levels may contribute to residual cardiovascular risk in patients with well-controlled LDL-C levels; however, non-HDL-C levels at admission did not seem to be predictive for patients with ACS. Detection and treatment of secondary lipid targets such as high TG and low HDL-C levels may be important for the prevention of cardiovascular diseases.