BACKGROUND The skeletal protein osteocalcin is gamma-carboxylated by vitamin K. High serum uncarboxylated osteocalcin reflects low vitamin K status. In vitro and animal studies indicate that high uncarboxylated osteocalcin is associated with reduced insulin resistance. However, associations between osteocalcin and measures of insulin resistance in humans are less clear. OBJECTIVE Our aim was ...

The synthesis of osteocalcin, the major non-collagenous protein of adult bone, was examined in cultures of 21-day fetal rat calvariae. Osteocalcin was measured by a sensitive and specific radioimmunoassay. Osteocalcin concentration in unincubated calvariae was 14.5 +/- 0.5 ng/calvaria. After incubation, there was a continuous increase in bone and medium osteocalcin, and by 96 h the values were ...

OBJECTIVE The study aimed to assess the possible systemic effects of intratympanic dexamethasone (IT-Dex) on the hypothalamic-pituitary-adrenal (HPA) axis, inflammation, and bone metabolism. DESIGN A prospective cohort study including 30 adult patients of a tertiary referral ENT clinic treated with 9.6 mg IT-Dex over a period of 10 days was carried out. METHODS Effects on plasma and salivar...

Osteocalcin is one of the most abundant noncollagenous proteins found in adult bone. It is a highly conserved gamma-carboxyglutamic acid-containing protein that is believed to be produced exclusively by osteoblasts. In this study, intracellular and extracellular localization of osteocalcin in osteosarcoma was examined with anti-osteocalcin antibody and in situ hybridization using a synthetic ol...

Osteocalcin (bone Gla protein) is an extracellular matrix protein synthesized by osteoblasts that is a marker of bone. Osteocalcin probably originated in the ancestors of Teleostei or bony fish and of the Tetrapoda or amphibians, reptiles, birds, and mammals. We have characterized the Cyprinus carpio (carp) osteocalcin for mineral binding to hydroxyapatite, amino acid sequence, and extent of se...

Vitamin K is essential for bone health, but the effects of low-dose vitamin K intake in Japanese subjects remain unclear. We investigated the effective minimum daily menaquinone-7 dose for improving osteocalcin γ-carboxylation. Study 1 was a double-blind, randomized controlled dose-finding trial; 60 postmenopausal women aged 50-69 y were allocated to one of four dosage group and consumed 0, 50,...

We evaluated comparatively six commercially available osteocalcin kits: ELSA-OST-NAT IRMA (CIS), ELSA-Osteo IRMA (CIS), Osteocalcin IRMA (Nichols), OSTK-PR RIA (CIS), OSCA Test Osteocalcin RIA (Henning), and Osteocalcin RIA (Nichols). All of them presented acceptable values of variance, sensitivity, and serial dilutions. However, only the ELSA-OST-NAT, ELSA-Osteo, and OSCA Test kits had analyti...

OBJECTIVES Osteocalcin, a bone-derived protein, has recently been reported to affect energy metabolism. We investigated the relationship between serum osteocalcin and parameters of adiposity, glucose tolerance, and lipid profile in Chinese subjects. METHODS Serum osteocalcin was measured by electrochemiluminescence immunoassay in 254 men (128 with newly diagnosed type 2 diabetes mellitus (T2D...

Both leptin and osteocalcin have been found to affect growth-plate cartilage development through regulation of the physiologic processes of endochondral bone formation. Leptin mediates bone development and osteocalcin secreted in the late stage of osteoblast differentiation. The relationship between leptin and osteocalcin expression in the chondrogenic cells line is still not clear. Thus, the a...

Background: Lead is one of the sustainable metals with devastating effects on many tissues. This study, examined the adverse effect of lead poisoning on the gene expression of collagen type II and osteocalcin by mesenchymal stem cells (MSCs) cultured in chondrogenic and osteogenic media, respectively. Methods: We used 18 male Wistar rats, divided in 3 groups. In addition to libitum feed as the...