BACKGROUND Osteoblast phenotypic abnormality, namely the expression of collagen type III, has been shown previously in fracture non-union woven bone. AIMS To investigate osteoblasts from fracture non-unions for evidence of gene expression of non-collagenous bone matrix proteins that have been implicated in mineralisation, namely matrix gla protein (MGP), osteonectin, osteopontin, and osteocal...

In total hip arthroplasty, wear particles generated at articulating surfaces and interfaces between bone, cement and implants have a negative impact on osteoblasts, leading to osteolysis and implant loosening. The aim of this experimental study was to determine the effects of particulate wear debris generated at the interface between straight stainless steel hip stems (Exeter(®)) and three diff...

The objective of this study was to explore the mechanism underlying osteoblast suppression in the process of hematopoietic stem cells mobilization induced by granulocyte colony-stimulating factor (G-CSF). The apoptosis of human and mouse osteoblasts was examined by detecting caspase 3. The levels of serum DKK1 and osteocalcin in the supernatant of co-culture of mouse osteoblasts and mouse bone ...

Iron metabolism is tightly regulated in osteoblasts, and ferroportin 1 (FPN1) is the only identified iron exporter in mammals to date. In the present study, the regulation of FNP1 in human osteoblasts was investigated following various iron treatments. The human osteoblast cell line hFOB 1.19 was treated with ferric ammonium citrate (FAC) or desferrioxamine (DFO) of various concentrations. The ...

The extracellular matrix may be considered as an insoluble local mediator which plays an important role in regulating cell function. Communication between the cell and its matrix occurs via the integrins, a family of transmembrane proteins composed of non-covalently linked alpha and beta subunits. The aim of this study was to establish which integrins are present on human bone cells in situ and...

We recently reported that the pharmacological inhibition of calcineurin (Cn) by low concentrations of cyclosporin A increases osteoblast differentiation in vitro and bone mass in vivo. To determine whether Cn exerts direct actions in osteoblasts, we generated mice lacking Cnb1 (Cn regulatory subunit) in osteoblasts (DeltaCnb1(OB)) using Cre-mediated recombination methods. Transgenic mice expres...

The tumor microenvironment is comprised of diverse stromal cell populations in addition to tumor cells. Increasing evidence now clearly supports the role of microenvironment stromal cells in tumor progression and metastasis, yet the regulatory mechanisms and interactions among tumor and stromal cells remain to be elucidated. Bone metastasis is the major problem in many types of human malignanci...

R-spondin (Rspo)s proteins are a new group of Wnt/beta-catenin signaling agonists. These signaling molecules are known to be involved in the developmental stages of skeletal system. Recent studies in various murine osteoblast models have proposed that Rspo 1 may interact with Wnt signaling pathway to induce differentiation in osteoblasts. Though findings in murine osteoblasts implicate a synerg...

OBJECTIVE Extra corporeal shock waves (ESW) have been proposed as additional therapy in bone fracture repair and osteoarthrtitis (OA). However, little is known on the effects of ESW on osteoblast metabolism. The aim of this study was to evaluate phenotype changes of healthy and OA human osteoblasts following ESW treatment. METHODS Osteoblasts were isolated from subchondral bone of 13 OA patie...

Bone marrow stromal cells maintain the adult skeleton by forming osteoblasts throughout life that regenerate bone and repair fractures. We discovered that subsets of these stromal cells, osteoblasts, osteocytes, and hypertrophic chondrocytes secrete a C-type lectin domain protein, Clec11a, which promotes osteogenesis. Clec11a-deficient mice appeared developmentally normal and had normal hematop...