Bone Abstracts

Background: Long-term use of bisphosphonates has raised concerns about the association with Atypical Femur Fractures (AFFs) that have been reported mainly in postmenopausal women.Clinical case: An 18-year-old patient with juvenile osteoporosis based on X-linked osteoporosis due to a PLS3 mutation developed a low trauma femoral fracture after seven years of intravenous and two years of oral bisphosphonate use, fulfilling the revised ASBMR diagnostic crite...

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Communication between osteoblasts and osteoclasts is crucial for bone remodeling. Thrombin and its thrombin receptor (TR; PAR-1) are expressed in osteoclasts and osteoblasts, respectively. To date, the physiological roles of thrombin and TR in bone metabolism have not been elucidated. Therefore, we fully characterized the bone phenotype of mice lacking the thrombin receptor.We performed bone microarchitectural analyses of the femurs of 10–12 week ol...

Objectives: Strong coordination between osteoblasts and bone marrow cells is fundamental for the regulation of healthy bone turnover and other (patho)physiological processes. Extracellular vesicles (EVs) mediate communication between cells via horizontal transfer of proteins and nucleic acids. Osteoblasts secrete EVs in the form of matrix vesicles involved in bone mineralization, however, information about a role in intercellular communication is still lacking. In this study, ...

Transient receptor potential vanilloid channels (TRPVs) have been implicated in Ca2+ homeostasis and bone metabolism. In particular, TRPV4 deficiency was shown to cause sexual dimorphism in bone metabolism and osteoporotic fracture risk. Cortical bone structure was reported to be altered in male TRPV4 knock-out (TRPV4−/−) mice but not in female TRPV−/− mice compared to sex-matched wildtype (TRPV4+/+) animals.To gain knowledge on t...

Background: Elevated plasma homocysteine levels are a risk factor for osteoporotic fractures. Supplementation with vitamin B12/folic acid lowers homocysteine levels. This study aimed to determine whether vitamin B12/folic acid supplementation reduces osteoporotic fracture incidence in hyperhomocysteinemic elderly.Methods: B-PROOF is a double-blind, randomized, placebo-controlled trial including 2 919 participants aged ≧65 years with elevated homocyste...

Introduction: Bisphosphonates gain increasingly greater significance in treatment oncologic diseases with bone metastasis. However, a lot of articles have lately been published in dental and oncological journals on jaw osteonecrosis (ONJ) associated with long-term ingestion of bisphosphonates. Besides extension of clinical recommendations for zolendronate use, most commonly referred to in connection with ONJ, for treatment of Paget’s diseaseand other disturbances of bone ...

Objective: Serotonin is a neurotransmitter with multiple functions in the gastrointestinal tract and CNS. Recent animal studies indicate that serotonin regulates bone mass and remodelling. In humans, a handful of studies have shown decreased bone mineral density (BMD) in adults treated with selective serotonin reuptake inhibitors (SSRI) for depressive symptoms. Although SSRI’s are prescribed in pediatric practice, there are few studies examining the effect of SSRIs on bon...

Objective: Vascular calcification contributes to the pathogenesis of atherosclerosis, hypercholesterolemia, end stage renal disease, and diabetes, and is caused by genetic ablation of matrix Gla protein (MGP) in mice. Genetic ablation of MGP in mice results in excessive calcification of the vessel wall associated with a chondrocyte-like trans-differentiation in smooth muscle cells (VSMCs). Canonical β-catenin signaling is activated in the calcified arterial Mgp&#8722...

Destruction of the articular cartilage is the major feature of Osteoarthritis (OA). Ageing is the primary risk factor, but how ageing results in OA is still an enigma. In OA, articular chondrocytes degrade their own matrix, while in healthy articular cartilage they preserve it.Transforming growth factor β (TGFβ) is a central regulator of chondrocyte proliferation, differentiation and extracellular matrix production. Deregulation of TGFβ si...