Bone Abstracts

We previously demonstrated the involvement of Lcn2 in bone loss induced by mechanical unloading. This prompted us to investigate bone phenotype of Lcn2−/− mice by μCT, which showed an osteopenic phenotype, characterized by 40% lower trabecular bone volume, 50 and 21% lesser trabecular number and thickness, respectively, and 20% higher trabecular separation, compared to WT, while cortical thickness was significantly lower (40%) only in elderly Lcn2<s...

Background: Cabozantinib (CBZ) is a receptor tyrosine kinase inhibitor with activity against MET, VEGFR2, FLT3, c-KIT, and RET. Pre-clinical studies in models of prostate cancer bone metastasis demonstrated that CBZ treatment induced both a suppression of tumour growth and an alteration in bone remodelling, suggesting that both tumour and bone microenvironment represented potential CBZ targets. This is the first study exploring the potential direct activity of CBZ in bone usin...

Dominant osteogenesis imperfecta (OI) is a bone disease mainly caused by collagen type I mutations and characterized by bone fragility and growth delay. Nowadays no definitive cure is available. A zebrafish OI model (Chihuahua) carrying an heterozygous G574D substitution in the α1 chain of collagen type I was generated by ENU mutagenesis and is available in our laboratory. Control (WT) and mutant (Chi+/−) fish growth was followed up from day 1 post fertilization to ...

Background and aim: Multifaceted risk factors impair bone mass in childhood cancer survivors. Aims of the study were to evaluate bone mass and it’s determinant and fracture prevalence in CBCS 2 (G+2) or 5 (G+5) years after off therapy (OT).Methods: Seventy-three (G+2) and 87 (G+5) CBCS were evaluated at 12.9±4.2 and 14.9±4.4 yrs, respectively. Diagnoses were: astrocytic (G+2:n=25, G+5:n=24), embryonal (G+2:n=28, ...

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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 &gE;65 years with elevated homocyste...

Besides its well known effect on longitudinal bone growth, GH plays a role in the maintenance of adult bone mass. As aging progresses GH levels decline, bone mass decreases and mesenchymal precursors show a reduced osteogenic differentiation capacity resulting in an increase in bone marrow adipocytes. We investigated the effect of GH on MSC differentiation and the possible involvement of microRNA in this process. Human MSC derived from trabecular specimens, waste material of o...