Glucosylgalactosylhydroxylysine is a bone formation and bone resorption marker that is related to bone turnover processes during growth and development as well as metabolic bone diseases.
Ganglioside GQ1b is a tetrasialoganglioside that contains two sialic acid residues linked to an inner galactose unit. It stimulates phosphorylation of several ecto-type protein kinase substrates on the surface of GOTO human neuroblastoma cells when used at a concentration of 5 nM. Ganglioside GQ1b promotes differentiation of murine embryonic stem cells (mESCs) to neuronal precursor and glial cells via activation of the ERK1/2 pathway. It also induces differentiation of murine keratinocytes through phosphoinositide turnover. Ganglioside GQ1b mixture contains ganglioside GQ1b molecular species with C18:1 and C20:1 sphingoid backbones.
Osteocalcin (1-49) is a non-collagenous peptide that is secreted by osteoblasts and odontoblasts and comprises 1-2% of the total protein in bone. Secretion of osteocalcin (1-49) is stimulated by 1,25-dihydroxy vitamin D and plasma levels increase in diseases that induce dysregulated bone turnover such as osteoporosis, Paget's disease, and primary hyperparathyroidism. Osteocalcin (1-49) is positively correlated with insulin sensitivity and negatively correlated with high blood glucose levels in women. In vitro, osteocalcin induces chemotaxis of MDA-MB-231 breast cancer cells, human peripheral blood monocytes, and rat osteosarcoma cells with osteoblast-like characteristics. It is also expressed by vascular smooth muscle cells (VSMCs) displaying an osteoblast-like phenotype and has been positively associated with calcification of aortic tissue and heart valves in humans.