Lower serum osteocalcin is associated with more severe metabolic syndrome in elderly men from the MINOS cohort

Abstract

Background: Bone has emerged as an endocrine organ regulating energy metabolism through secretion of osteocalcin. In epidemiological studies, presence of metabolic syndrome (MetS) was associated with lower osteocalcin level. Objectives: We evaluated whether osteocalcin level was associated with MetS severity in men and whether it was more strongly associated with MetS compared with N-terminal propeptide of type I procollagen (PINP), bone-specific alkaline phosphatase (BAP), and C-terminal telopeptide of type I collagen (bCTX). Methods: We included 798 men aged 51-85 years for total osteocalcin measurement. Number of MetS criteria was used to define severity. We used polytomous logistic regression to assess the relationship between MetS severity and osteocalcin level. Results: Thirty percent of men had MetS. In patients with MetS, the higher the number of MetS traits were present, the lower was the average osteocalcin level (0-2 criteria: 551 men: 19.5G6.7 ng/ml, three criteria: 155 men: 19.3G7.4 ng/ml, four criteria: 72 men: 17.3G5.7 ng/ml, and five criteria: 20 men: 15.0G5.1 ng/ml; P for trendZ0.002). In the polytomous logistic regression model, an increase in osteocalcin level of 10 ng/ml was associated with lower prevalence of severe MetS: three criteria (odds ratio (OR)Z0.93 (0.70-1.24)), four criteria (ORZ0.54 (0.34-0.84)), and five criteria (ORZ0.28 (0.10-0.82)) in comparison with no MetS (P for trendZ0.008). After adjustment, using stepwise analysis of the polytomous logistic regression model, we observed that osteocalcin, age, and apparent free testosterone entered in the model but not other bone markers (PINP, bCTX, and BAP). Conclusion: In older Caucasian men, total osteocalcin level was associated with MetS severity. Osteocalcin was more strongly associated with MetS severity than other bone turnover markers.

Vhl deletion in osteoblasts boosts cellular glycolysis and improves global glucose metabolism

“…This uptake is similar to or even higher than that seen in some of the established glucose-avid tissues such as heart, liver, and brain, a finding that is in line with other recent work (30). Plausible explanations are the large total contribution of the skelhumans (3,28,29). Osteocalcin -/-mice show an obese phenotype with hyperglycemia, hypoinsulinemia, and reduced insulin secretion and sensitivity compared with WT mice (3).…”

High plasma osteocalcin is associated with low blood haemoglobin in elderly men: the MrOS Sweden Study

“…However, diabetic subjects have lower plasma osteocalcin levels than those without diabetes. Of interest, there seems to be an association between low osteocalcin and the metabolic syndrome including its individual components . Indeed, adults with metabolic syndrome have increased Hb levels in part due to insulin resistance and compensatory hyperinsulinaemia.…”

“…Despite adjustments for all known confounders including the metabolic syndrome, the association between Hb and osteocalcin remained. Hb was correlated negatively with age as described by others ; however, we found that osteocalcin was not associated with age, consistent with one but not with another earlier study in which increased osteocalcin concentrations in men in their seventh decade were observed . Notably, our studied population was relatively homogenous in terms of age.…”

Complex interplay among adiposity, insulin resistance and bone health

“…In one study, glycemia was inversely associated with OC (55). In a meta-analysis, OC was associated with HOMA-β and inversely correlated with HbA1c, fasting plasma glucose, HOMA-IR, central obesity and the metabolic syndrome (56)(57)(58)(59)(60)(61). Another study reported that higher OC concentration was associated with lower HbA1c in a cohort with type 1 diabetes (62).…”