Bone Abstracts

Vertebral fractures (VF) defined by morphometric analysis of spine radiographs are the most common complication of osteoporosis. Those that come to medical attention, with symptoms such as back pain and kyphosis are termed clinical vertebral fractures (CVF) and account for significant morbidity and mortality. Although much progress was made in identifying loci for bone mineral density, the genetic determinants of CVF remain unclear. Here we present the initial results from a g...

Epigenetic mechanisms regulate gene expression and are heritable through cell divisions even though they do not involve modifications in the gene sequence. They include methylation and other chemical modifications of cytosine nucleotides, histone posttranslational modifications, microRNAs and other non-coding RNAs. Most cytosines in the human genome are methylated, particularly in the inactive, tightly packed, heterochromatin of autosomes, and the inactivated X-chromosome in f...

Alkaline phosphatase activity is critical for the mineralization of the bone matrix. Indeed, inactivating mutations of the ALPL gene, encoding the isoenzyme expressed in bone and liver, may result in the severe abnormalities of bone and other connective tissues that characterize hypophosphatasia. Nevertheless, the clinical spectrum of hypophosphatasia is rather broad and variable between a within families. Thus, along severe infantile forms, there are adult forms with mild man...

Osteoporosis (OP) is characterised by reduced bone mass, due to an insufficient osteoblast-mediated bone formation, unable to replace the bone tissue removed by osteoclasts. Mesenchymal stem cells (MSCs) are multipotent cells capable of differentiating into osteoblasts, adipocytes and chondrocytes. Epigenetic marks like DNA methylation could influence the differentiation potential of these cells into osteoblasts and, consequently, the risk of OP. To explore this hypothesis, we...

Background: Surgical treatment of type 2 diabetes, specially in obese patients, has provided good results in the control of blood glucose and Hb1Ac although its effect on bone health is not clear. The aim of this study was to evaluate gene expression of bone remodelling markers in type 2 diabetic Goto-Kakizaki (GK) non-obese rats after gastrojejunal bypass and sleeve gastroplasty, and their relationship with hormonal parameters.Materials and methods: We ...

Sclerostin, encoded by the SOST gene, functions as an inhibitor of the Wnt pathway and thus it is an important regulator of bone homeostasis. The fact that osteoblasts, the only cells expressing SOST, lay buried deeply in the bone matrix, poses intrinsic difficulties to the study of the regulation of this gene. Since RUNX2 and SP7/OSX are two known regulators of the differentiation of cells of the osteoblastic lineage, the aim of this study was to determine t...

Individuals with Down syndrome (DS) have a number of phenotypic features, including a short stature. It has been reported that people with DS have lower areal BMD than the general population, but this may be a biased result due to the smaller size of the skeleton, and it is unclear if individuals with DS have fragile bones. Thus, the objective of this study was to explore the skeleton of DS using two techniques, TBS and calcaneal ultrasound, which are not influenced by bone si...

Background: Osteogenesis imperfecta (OI) is a heterogeneous group of inherited disorders of bone formation, resulting in low bone mass and an increased propensity to fracture. It is a variable condition with a range of clinical severity. About 90% of patients with a clinical diagnosis of OI have a mutation in the COL1A1 or COL1A2 genes, which shows an autosomal dominant pattern (AD) of inheritance. Other genes are associated with the autosomal recessive (AR) ...

Romosozumab is an investigational bone-forming agent that inhibits sclerostin. Recent data demonstrated that it stimulated bone formation, decreased bone resorption, and led to rapid and substantial increases in areal bone mineral density (BMD; McClung, J Bone Miner Res 27 (S1) S8–S9, 2012). In a Phase 1b, randomized, double-blind, placebo-controlled, multiple dose study, we studied the effects of romosozumab administered for 3 months and follow-...

Objectives: Creation of reference curves for areal bone mineral density (aBMD) and bone mineral content (BMC) with consideration of relevant anthropometric variables.Methods: Analysis of the dual-energy X-ray absorptiometry (DXA) data collected as part of the Bone Mineral Density in Childhood Study1, including 2012 boys and girls, 5–22 years old, with a total of 10 525 visits, resulting in aBMD and BMC observations at the lumbar spine, hi...