Bone Abstracts

Introduction: Elevated FGF-23 serum levels are induced by hyperphosphatemia and are linked to poor skeletal mineralization and adverse outcomes including vascular calcification and mortality. Recently, it was shown that FGF-23 levels are substantially elevated in acute kidney injury (AKI), and that higher levels in AKI are associated with a greater risk of adverse outcomes.Methods: In 25 vitamin D deficient (25(OH)D <20 ng/ml) critically ill adults w...

Introduction: Atypical markers will provide interesting information in order to assess the bone metabolism. Serotonin has a dual action related to the bone and its serum level is the easiest to use in daily clinical practice also the exact value is not very well described up to this moment.Aim: We correlate to serum levels of serotonin with different results of clinical bone health evaluation in menopausal women.Materials and metho...

Introduction: Myostatin (growth differentiation factor 8, GDF-8) has an important role in the regulation of muscle mass, and mice lacking the myostatin gene show a generalized increase in bone density and strength. Type 2 diabetes subjects have an increased risk of fragility fractures despite of higher bone mass. Taking into account the myostatin influence in bone strength a better understanding of myostatin actions in type 2 diabetes is of interest.Obje...

Purpose: In X-linked hypophosphatemia (XLH), elevated serum FGF23 causes low serum phosphorus (Pi) and inappropriately normal 125-dihydroxyvitamin D (125(OH)2D) levels. We report PK and PD of KRN23 following single ascending dose administration in adults with XLH.Methods: 38 XLH patients with baseline FGF23≥30 pg/ml were randomized to receive a single dose of KRN23 (K) or placebo (P) either i.v. (0.003–0.3 mg/kg) or s.c. (0.1–1...

We and others have recently showed that patients with type 2 diabetes mellitus (T2DM) have a higher risk for fracture, although they have normal or slightly higher bone mineral density (BMD). These findings suggest that bone fragility in T2DM, which is not defined by BMD, may contribute to fracture risk. Hyperglycemia accelerates the formation of advanced glycation end products (AGEs) and causes diabetic complications. AGEs including pentosidine are also known to cause bone fr...

Background: Autocrine and paracrine Wnt signaling operates in stem cell populations and regulates mesenchymal lineage specification. In Wnt producing cells, Wntless (GPR177) supports the transport of Wnt from the trans-Golgi network (TGN) to the cell surface in vesicles, from which Wnt is then released. The retromer complex (VPS35) interacts with Wntless and retrieves Wntless from endosomes back to TGN, thereby maintaining the normal levels of Wntless protein. V-ATPases-driven...

Glucocorticoid (GC)-induced osteoporosis (GIO) occurs in patients undergoing therapeutic intervention for inflammatory disorders such as rheumatoid arthritis and lupus. The effect of long-term GC administration on bone turnover was investigated in two frequently used mouse strains; C57BL/6 and CD1 in order to assess the influence of genetic background.GIO was induced in 12 weeks old female C57BL/6 and CD1 mice by s.c. insertion of long-term (60 days) rel...

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...

Background: Zoledronic acid (ZA) is associated with a transient post-infusional acute phase reaction (APR) due to the activation of γδTCR lymphocytes (γδTcells).Aims: To investigate if APR correlates with γδTcell percentage or cytokine polarization, or with 25-OH vitamin D levels; to identify a 25-OH vitamin D level associated with a lower risk of APR.Methods: Sera for ELISA test (IFNγ, IL17, and ...

Bisphosphonate treatment reduces fracture risk in women with postmenopausal osteoporosis. However, some patients have an inadequate response to treatment. Estradiol and sclerostin play an important role in bone metabolism. Sclerostin is an endogenous inhibitor of osteoblastic activity and estrogen deficiency increases osteoclast activity and bone resorption.We examined the influence of both measures on fracture incidence in postmenopausal osteoporosis in...