Bone Abstracts

Osteoclasts are produced by fusion of pre-osteoclasts derived from stem cells of the monocyte/macrophage lineage in the presence of receptor activator of NF-κB ligand (RANKL) produced by osteoblasts. The phytoestrogens; genistein and daidzein, which are isoflavones found in Leguminosae such as soybeans, are currently being investigated for prevention of postmenopausal osteoporosis. Some polyunsaturated fatty acids (PUFAs) have been shown to exert a bone protectiv...

Bisphosphonates (BPs) such as zoledronic acid (ZA) are widely used to treat bone diseases. The use of BPs can lead to osteonecrosis of the jaw (ONJ), but it is not clear why in particular the jaw bone is affected. Previously, it was shown that osteoclasts derived from different bone sites have different properties. We hypothesize that BPs have distinct effects on bone-site specific osteoclasts or precursors. To investigate this, female C57BL/6J mice were injected intraperitone...

The PTH type 1 receptor (PTH1R) is an important modulator of bone remodeling. In mice, PTH1R ablation in osteocytes produces trabecular bone reduction and impaired calcium homeostasis; meanwhile, its overexpression in these cells promotes periosteal and endocortical bone formation. Osteocytes can translate mechanical stimuli into bone-forming signals. Skeletal unloading induces osteocyte apoptosis and bone loss, whereas mechanical stimuli prevent osteocyte apoptosis through in...

Caffeine is a methylxanthine found in many foods and is widely consumed by the human population. Therefore, its effects and mechanisms in various tissues have been widely studied. But despite changing the postnatal bone growth, there are few studies about its effect on growth cartilage. The objective of this study was to evaluate the In vitro effects of caffeine on proliferation, apoptosis and gene transcripts expression of chondrogenic differentiation in growth carti...

Despite the presence of skeletal anomalies in fetuses of female rats treated with caffeine, their effect on bone’s formation and growth have not yet been elucidated. The objective of this study was to evaluate the effects of caffeine on the formation and endochondral bone growth in rats. There had been used 36 Wistar rats distributed among the control group and others treated with caffeine at doses of 25, 50, and 100 mg/kg. Treated groups received caffeine daily throughou...

Since the identification of LRP5 as the causative gene for the osteoporosis pseudoglioma syndrome (OPPG) as well as the high bone mass (HBM) phenotype, LRP5 and the Wnt/β-catenin signalling have been extensively studied for their role in the differentiation and proliferation of osteoblasts, in the apoptosis of osteoblasts and osteocytes and in the response of bone to mechanical loading. However, more recently the direct effect of LRP5 on osteoblasts and bone formation has...

In clinical research protocols, HR-pQCT images (XtremCT Scanco, voxel size: 82 (μm3) are carried out to evaluate trabecular and cortical bone changes induced by osteoporosis and treatments. Micro-computed tomography (μ-CT) has become a standard tool for examination of trabecular and cortical bone in 3D.The purpose of this study is to evaluate the accuracy of cortical and trabecular measurements derived from HR-pQCT images with morpho...

Introduction: Cardiovascular disease and osteoporosis have often been reported to coexist in older people. However, the literature is conflicting regarding size and indeed direction of the association. The aim of the present study was therefore to assess associations between the Framingham general cardiovascular risk score and bone characteristics in a cohort of older adults.Methods: We studied 374 men and 379 women, born 1931–1939, who participated...

Background: Zoledronic acid (ZA) for the treatment of osteoporosis (OP) is associated with a transient post-infusional acute phase reaction (APR) due to ZA-mediated activation of γ-δ TCR lymphocytes (γ-δTCR) and production of cytokines.Primary objective: To investigate if OP patients developing APR (APR+) after ZA infusion have lower 25-OH vitamin D (25-OHvD) levels and a higher percentage of γ-δTCR compared to patients with...

Background: Although both testosterone and estrogens are considered essential for normal bone growth, epiphyseal maturation and bone mass accrual during adolescence, only very few data concerning the changes of estrogens, bone maturation, bone mineral density (BMD) and bone geometry in healthy boys at different pubertal stages have been published.Objectives: This study aimed to analyze the relationship between sex steroids and more especially estrogens a...