Association between osteocalcin and metabolic syndrome in postmenopausal women

Undercarboxylated osteocalcin (ucOC) has been proved as a regulator of glucose and fat mass in an animal model. This study examined the association between osteocalcin and metabolic syndrome (MetS) in postmenopausal women. We selected 135 postmenopausal women and determined anthropometric values [waist-hip ratio (WHR), visceral fat area (VFA), body fat mass (BFM), and skeletal muscle mass (SMM)], the lipid profile, fasting plasma glucose (FPG), insulin, high-sensitivity C-reactive protein (hs-CRP), homeostasis model assessment of insulin resistance (HOMA-IR), serum leptin and adiponectin level, and serum tOC and ucOC level. There were 52 postmenopausal women in the MetS group. After adjusting for age and years since menopause, ucOC was negatively correlated with WHR, VFA, BFM, triglyceride, fasting insulin, HOMA-IR, and serum leptin and was positively correlated with serum adiponectin. The odds ratio for MetS was significantly lower in the highest quartile than the lowest quartile after adjusting for age, years since menopause, and BMI. In multiple regression analysis, serum leptin and HOMA-IR were the most important predictors of the independent variables that affect serum ucOC. ucOC showed an inverse correlation with markers of insulin resistance, central obesity, and the presence of MetS in postmenopausal women and appears to protect against MetS. Further large-scale clinical and experimental studies are needed to clarify the potential of ucOC as a predictor of MetS in postmenopausal women.