Bone Abstracts

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...

RANKL, the receptor activator of nuclear factor kappa B ligand, is an essential factor for the formation of mature osteoclasts. Together with its receptor RANK and its antagonist Osteoprotegerin (OPG) RANKL is a key regulator in bone metabolism1. RANKL is a membrane-bound protein that can be segregated to a soluble form (sRANKL), whereas only the latter has been reported to be bioactive2. Due to its low circulating levels and the nature of the analyte bin...

Introduction: Recent data suggest that lipid metabolism imbalances affect bone cell function and therefore may result in the development of osteoporosis. We investigated the role of apolipoprotein-E (ApoE), a plasma protein playing cardinal role in lipoprotein metabolism, in the regulation of osteoblast and osteoclast function and the pathogenesis of osteoporosis.Material and methods: We used apoE deficient (ApoE−/−) and C57BL/6 (c...

There are few cases of pregnancy described in which the fetus was exposed to some bisphosphonates, but not ibandronate to our knowledge. Meanwhile, ibandronate has a high protein binding rate (87%) and short tissue’s half-life (24 days) and might be a less potentially harmful drug in the event of pregnancy.A 23-year-old woman was admitted to our hospital with evident ACTH-dependent Cushing’s syndrome CS (24 h urinary free cortisol – 2413 n...

Sclerosing bone dysplasias (too much bone diseases) are divided into two major groups, one group caused by impaired bone resorption and the other by increased bone formation. The former comprises a group of osteopetrosis (disorders due to abnormal osteoclastogenesis or osteoclast dysfunction) with relatively homogeneous skeletal phenotypes. By contrast, the latter encompasses a complex group of disorders with heterogeneous pathogeneses and diverse skeletal phenotypes.<p cl...

Background: Epidermolysis bullosa (EB) is a rare, genetic skin disorder characterized by increased skin fragility after relatively minor trauma. It varies in severity even within the same subtype, ranging from a minor inconvenience to a severely disabling or life threatening disorder. In generalized forms, EB is a systemic disorder in which osteoporosis is a frequent manifestation.Presenting problem: While the mutations that cause EB do not have a direct...

The microenvironment of osteolytic metastases includes carcinoma cells derived from the primary lesion as well as bone-forming and bone-resorbing cells, namely osteoblasts (OB) and osteoclasts (OC). At this site, both the high glycolysis of cancer cells, and the bone resorption process result in a very acidic milieu. This, in turn, induces the surrounding stroma and OB to secrete pro-inflammatory cytokines and growth factors that promote tumorigenesis and cancer-associated ost...

Infantile malignant osteopetrosis (IMO) is a rare, lethal, recessive disorder characterized by dysfunctional osteoclasts. TCIRG1, encoding the osteoclast V-ATPase, is mutated in 50% of IMO patients. We have previously shown that the resorptive function in osteoclasts derived from IMO patients can be restored in vitro by expressing TCIRG1 using a lentiviral vector. In this study, we aim to investigate the cellular response to vector-derived TCIRG1 expression and to det...

The purpose of this study is to understand the changes of TBS scores in Asian females by comparing 1990’s and 2010’s DXA images.We have compared the DXA images of 3774 Korean females (age: 20–79) to Japanese (age: 20–79). While Korean DXA images were obtained in 2014 and 2015, Japanese data were obtained in 1996. Participants who have abnormal DXA images or lumbar disease were excluded. TBSiNsight® software (v. 2.1.1, ...

The purpose of this study is to assess the correlation of trabecular bone score (TBS) to variable factors, i.e. sex, age, body size and BMD. Moreover, we want to find variables of correlation coefficient change with aging.We randomly selected 2,906 subjects (1726 female and 1180 male, age range 20’s to 70’s) from several hospitals in Korea. Participants who have abnormal Dual Energy X-ray Absorptiometry (DXA) images or lumbar disease were exclu...