Correlation between obesity and bone health in Chinese children and adolescents

Background: Many researchers suggested that obesity and bone metabolism are correlative. Nevertheless, there are still obscured regarding the interactions among obesity and bone biologic markers, especially in children and adolescents. Methods: A cross-sectional study was performed in 4 groups of 95 children/adolescents. Serum adiponectin, ghrelin, osteopontin (OPN), and osteoprotegerin (OPG) were examined by enzyme-linked immunosorbent assay (ELISA). Blood lipid levels including total cholesterol (TC), triglyceride (TG), high-density lipoprotein (HDL), low-density lipoprotein (LDL) were tested by enzymatic colorimetry. Results: Serum adiponectin level was lower in overweight group than that of lean group (P < 0.05). Ghrelin levels in overweight and obese groups significantly decreased compared with lean group (P < 0.05, respectively). Serum adiponectin and ghrelin levels inversely correlated with body mass index (BMI). Serum adiponectin reversely related with TG in all the subjects. For the female, serum adiponectin had a negative relation with TG, TC and LDL. Serum OPN had a positive relation with ghrelin level and negative relation with BMI in all subjects. Conclusions: Serum adiponectin and ghrelin levels were down-regulated in obesity. BMI inversely correlated with the serum adiponectin and ghrelin levels. There were a significant negative correlation between adiponectin level and TG level. Serum OPN level had a significantly positive correlation with ghrelin and negative correlation with BMI. Ghrelin may play a fundamental role in the pathogenesis of obesity and related bone metabolic risk diseases through OPN in Chinese children and adolescents.