The main sources of osteoblasts are bone, periosteum, bone marrow and extra bone tissue. And human embryo skull or newborn animal skull is a common source of osteoblasts.
Osteoblast regulatory factor
The differentiation process of osteoblasts is affected and regulated by genetic factors, hormone levels and cell regulatory factors. The regulation of osteoblast proliferation is mainly through the regulation of the cell cycle, that is, the regulation of cell replication of DNA and cell division under the action of mitogen
The vitamin D receptor (VDR), also known as the calcitriol receptor and also known as NR1I1 (nuclear receptor subfamily 1, group I, member 1), could be a member of the nuclear receptor family of transcription factors. Calcitriol, the active type of vitamin D, binds to VDR, which forms a heterodimer with the retinoid-X receptor. It then binds to a hormone response element on the DNA, leading to expression or transrepression of a particular gene product. The VDR not only regulates transcriptional responses but also involved in microRNA-directed post transcriptional mechanisms. In humans, the vitamin D receptor is encoded by the VDR gene.
TGF-β is an important local factor of bone metabolism, which can stimulate the proliferation and differentiation of a variety of bone tissue cells. TGF-β is an inactive macromolecular complex in the early stage of synthesis, and there is a large amount of inactive TGF-β in the bone matrix., when the pH is reduced or plasmin and cathepsin are activated, inactive TGF-β can be activated to regulate the formation of new bone in the bone resorption zone. TGF-β stimulates DNA synthesis and cell proliferation in non-transformed osteoblasts.
Osteogenesis Markers Proteins
Osteocalcin is a non-collagen hormone found in bones and dentin. Since osteocalcin has a gla domain, its synthesis depends on vitamin K. Osteocalcin acts as a hormone in the body in its uncarboxylated form, sending signals in the pancreas, fat, muscle, testes and brain. In the pancreas, osteocalcin acts on beta cells, causing beta cells in the pancreas to release more insulin. In adipocytes, osteocalcin triggers the release of adiponectin, which increases insulin sensitivity. In muscle, osteocalcin acts on muscle cells to promote energy use and utilization, and in this way enhances exercise capacity. In the brain, osteocalcin plays an important role in development and function.
Dentin matrix acid phosphoprotein 1 is a protein encoded by the DMP1 gene in humans. DeThis protein is essential for the correct mineralization of bones and dentin and is found in various cells in bone and tooth tissue. The protein contains a large number of acidic domains, multiple phosphorylation sites, functional arg-gly-asp cell attachment sequences, and a DNA-binding domain. In undifferentiated osteoblasts, it is mainly a nuclear protein that regulates osteoblast-specific gene expression. During osteoblast maturation, proteins are phosphorylated and exported to the extracellular matrix where they coordinate the formation of mineralized matrix. Mutations in this gene are known to cause autosomal recessive hypophosphatemia, which is manifested as disease and osteomalacia. The genetic structure is conserved in mammals. Two transcript variants encoding different isoforms have been described for this gene.
Calcitonin is a 32 amino acid peptide hormone secreted by parathyroid glandular follicular cells (also known as C cells) in the pharyngeal throat of many people. It reduces blood calcium (Ca2+), as opposed to the effect of parathyroid hormone (PTH). Calcitonin has been found in fish, reptiles, birds and mammals. It is not as important in humans as it is in other animals, because its function is usually not important in the regulation of normal calcium homeostasis. It belongs to the calcitonin-like protein family.