The association of plasma homocysteine levels with serum leptin and apolipoprotein B levels in childhood obesity

BACKGROUND: An elevated plasma total homocysteine (tHcy) level has recently been established as an independent risk factor for thrombosis and vascular disease. However, the relationship between hyperhomo- cysteinemia and cardiovascular disease and obesity remains contro- versial. The aim of the study was to investigate a possible relationship between plasma tHcy levels and measures of childhood obesity. SUBJECTS AND METHODS: Forty children and adolescents with exog- enous obesity and 20 non-obese subjects in an age-and sex-matched control group were investigated. Fasting samples were collected for plasma tHcy, serum insulin, leptin, vitamin B12, folate, creatinine and lipid parameters. Anthropometric characteristics and body composi- tions were assessed in both groups. RESULTS: The obese patients had significantly higher tHcy levels than the non-obese controls (14.3±11.8 μmol/L vs 8.7±5.9 μmol/L; P=0.017). In both groups, plasma tHcy was positively related to serum leptin, but serum apolipoprotein B (apo B) levels were positively related to plasma tHcy levels only in obese patients. CONCLUSIONS: Our study demonstrates for the first time that leptin and apo B are main correlates of tHcy in obese children and adolescents and suggests that hyperleptinemia and increased apo B may contribute to impairment of tHcy metabolism in childhood obesity.