Is circulating osteocalcin related to adipokines and overweight/obesity in children and adolescents?

Osteocalcin (OC) has recently been described to be involved in the regulation of glucose and energy metabolism. We aimed to evaluate whether or not OC serum levels were related to parameters of overweight and serum adipokine levels of healthy children and adolescents in dependence on gender and pubertal stage.In a cross sectional study (Leipzig Schoolchildren Project) 497 healthy, caucasian children and adolescents of all pubertal stages were included. We measured anthropometric data height, weight, fat mass, waist-to-hip ratio, pubertal development and performed biochemical analyses of osteocalcin, leptin, adiponectin and resistin serum levels by immunoassay.OC serum levels were associated with pubertal development achieving peak values at Tanner stage 3. There was no significant association of OC serum levels with overweight and obesity as measured by BMI and WHR. In addition, OC demonstrated no significant association with serum levels of leptin and adiponectin but a negative association with resistin in both genders independent of pubertal stages (r= - 0.329, p<0.0001).We conclude that there is no major relationship between OC and metabolism, but we can not exclude minor relations between OC and metabolism. The negative relationship with serum resistin levels might rather point to a link between OC and inflammatory states.