Osteocalcin (OC) is one of the most important non-collagen proteins in the bone matrix, and its level in the circulatory system is significantly correlated with changes in bone turnover rate which is an important marker of bone formation. Creative BioMart Biomarker offers high quality detection service for OC, ensuring high detection accuracy, sensitivity and efficiency for each sample.
OC, also known as bone γ-carboxyglutamic acid protein or BGP, is a 5.6 kDa secreted protein that contains 46-50 amino acids varying from species. OC is synthesized by osteoblasts or osteocytes. Since OC has a strong affinity for the bone matrix, most of it is present in the bone matrix, and only a small portion is present in the blood. OC has osteogenic or bone building functions, and osteoblasts secrete OC to stimulate the differentiation of osteoblast and the maturation of osteocytes. The transcription of the OC gene is regulated by 1-α, 25-hydroxy Vitamin D3, and its post-translational processing is regulated by Vitamin K. A carboxyl group is added to the 49 residue peptides on OC under the aid of Vitamin K to form a γ-carboxyglutamyl residue, which is necessary for the regulation of its activity. Depending on the level of carboxylation, OC can be divided into two groups, one is undercarboxylated osteocalcin (ucOC) and the other is carboxylated osteocalcin (cOC). The decarboxylated ucOC has little affinity with bone, and most of the ucOC will exist in the blood circulation. The cOC has a strong affinity with the bone matrix and can bind to the hydroxyapatite, so most of it is stored in the bone matrix. Usually the concentration of ucOC is not controlled by protein synthesis, but by the decarboxylation of OC and release from the bone matrix. The serum concentration of OC is related to the number of osteoblasts and bone formation, and it has been regarded as a laboratory marker for bone formation, but it can be said that OC reflects the entire metabolic activity of bone. Currently, OC is considered to be a very good indicator of bone turnover. OC detected in plasma is almost entirely derived from the synthesis of osteoblasts because it is rarely released during bone resorption. In healthy adults, OC levels are inversely related to sclerostin. In most of the conditions associated with bone mineralization, plasma OC concentrations increase. Diseases characterized by increased circulating OC concentrations include Paget’s disease, hyperparathyroidism, hyperthyroidism, osteomalacia, renal osteodystrophy, and acromegaly. In addition, OC levels decrease during hypothyroidism, hypoparathyroidism, growth hormone deficiency and early pregnancy, and can be used as an indicator for these diseases.
Figure 1. Osteocalcin synthesis in osteoblasts (Patti, et al. 2013)
Creative BioMart Biomarker strictly controls each specific experimental step in the OC detection procedure to ensure accurately quantify the level of OC in each sample.
At Creative BioMart Biomarker, we offer OC detection service that includes a variety of technical methods, you can communicate with our experts according to your research needs, and we will determine the final detection technological scheme based on the communication results. Please feel free to contact us, Creative BioMart Biomarker is here to offer you professional and thoughtful service.