Bone Abstracts

see PP292....

IGF1 is an osteo-anabolic factor that stimulates osteogenic precursor cell differentiation. IGF1 is produced in bone in response to mechanical stimulation, but also in mechanically-stimulated muscle cells. IGF1 enhances the rate of mRNA translation in muscle cells via activation of the PI3K/AKT/mTOR pathway, thereby increasing in muscle mass. Therefore we hypothesized that IGF1 not just enhances osteogenic differentiation of precursors, but also stimulates protein syn...

Osteoporosis is common in rheumatoid arthritis (RA). Since osteoblasts express receptors for CXCL8 and CCL20, which are produced by inflammatory cells around the inflamed joints in RA, we hypothesized that CXCL8 and CCL20 contribute to osteoporosis in RA by affecting osteoblast proliferation, differentiation, and osteoblast-osteoclast communication.Primary human osteoblasts were cultured±CXCL8 (2–200 pg/ml) and CCL20 (5–500 pg/ml) for 14 d...

Delayed fracture healing is frequently experienced in patients with systemic inflammation such as during rheumatoid arthritis (RA). The reasons for this are diverse, but could also be caused by inflammatory cytokines and/or growth factors in serum from patients with active disease. We hypothesized that serum from patients with active RA contains circulating inflammatory factors that inhibit differentiation of osteochondrogenic precursors.Serum was obtain...

Background: We identified a family with early onset X-linked osteoporosis and fracturesMethods: We performed whole exome sequencing of the X chromosome in three affected members. After discovering a putative pathogenic variant we performed Sanger sequencing of all exons of this gene in other members of this family and in 95 unrelated men suspected of OI type I without COL1A1/2 mutations. We also genotyped a SNP in this gene (minor allele frequency 0.02) ...