Relations between oxidized low-density lipoproteins and fat-soluble vitamin concentrations in obese children -...

Although lipid peroxidation products are formed during normal cell metabolism, they appear mostly in pathological conditions via producing an excess of free radicals that can react with unsaturated fatty acids, in particular low-density lipoprotein (LDL). The aim of this study was to investigate the relations between oxidized LDL (oxLDL), the fat-soluble vitamin status and the anthropometric parameters in prepubertal obese children.

Thirty-two obese (SDS-BMI >2) and 25 non-obese children (SDS-BMI <-1+1>) were included in the study. The concentration of oxLDL was determined in the serum by the ELISA assay. Vitamin A and E were measured by the high-pressure liquid chromatography method. Total cholesterol, LDL- and HDL-cholesterol, and triglyceride levels were determined by enzymatic methods.

The concentrations of oxLDL and vitamin A were higher in obese children than in normalweight controls by about 50% (p=0.01) and 40% (p=0.001), respectively. In obese children the significant positive correlation was found between oxLDL and vitamin A concentrations (<0.05). In addition, oxLDL correlated positively with BMI values (<0.05) and the amount of fat mass (kg) (<0.02) in these patients. Concentrations of vitamins A and E correlated with the level of total cholesterol (<0.05; <0.01, respectively).Moreover, a positive correlation between vitamin E and LDL-cholesterol was observed (<0.05).

Our preliminary study shows that oxLDL starts early during the prepubertal period and may precede atherosclerotic lesions. We suggest there is an occurrence of relationships between vitamin A and oxidized LDL in prepubertal obese children. Vitamin A and E concentrations are also associated with dyslipidemia in these patients.