Osteocalcin (OC) is an abundant extracellular calcium-binding protein synthesized by osteoblasts. Although most OC is bound to hydroxyapatite mineral during bone formation, a consistent amount is released directly to circulation. Plasma OC (pOC) levels are highly sensitive to stressful stimuli that alter stress-responsive hormones, such as glucocorticoids (cortisol or corticosterone) and the catecholamines norepinephrine and epinephrine.
View Article and Find Full Text PDFOsteocalcin, the most abundant member of the family of extracellular mineral binding gamma-carboxyglutamic acid proteins is synthesized primarily by osteoblasts. Its affinity for calcium ions is believed to limit bone mineralization. Several of the numerous hormones that regulate synthesis of osteocalcin, including glucocorticoids and parathyroid hormone, are also affected by stressful stimuli that require energy for an appropriate response.
View Article and Find Full Text PDFOsteocalcin (OC) is a small, acidic extracellular protein synthesized by osteoblasts during bone formation. 3 residues of gamma-carboxy glutamic acid, formed in a vitamin K dependent process, enable highly specific binding to ionic or bone mineral calcium. Some OC is released to circulation (pOC) and can serve as a biomarker of bone turnover.
View Article and Find Full Text PDFJ Mech Behav Biomed Mater
August 2009
In healthy bone there is a balance between bone resorption and formation. When an imbalance occurs there is an overall loss of bone mass leading to an increased risk of fracture. The deterioration is typically accompanied by changes in the non-collagenous proteins in the bone.
View Article and Find Full Text PDFEthanol consumption and mental stress activate the sympathetic nervous system, which can adversely affect bone. We compared six groups of 10 young adult rats, three with and three without 2 h daily restraint stress. Two groups consumed food and water ad libitum, two received food and 6% (w/v) ethanol as drinking water, and two received the amount of food consumed by ethanol rats the previous day plus water ad libitum (pairfed).
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