Bone Abstracts

Adiponectin may play a role in both bone and periodontal remodeling. In this study, the effect of repetitive local administration of human recombinant adiponectin on experimental tooth movement was examined.The first molar of 24 male Wistar rats was moved mesially by a closed coil spring ligated to the molar and anchored to the incisors in front for 14 days, with adiponectin injections every 3rd day. Amount of tooth movement was examined by feeler gauge ...

Epidemiological studies suggest that patients using proton pump inhibitors (PPIs) have increased fracture risk. We have previously shown that H+/K+ATPase beta-subunit knockout (KO) mice have reduced BMD, BMC and mechanical bone strength compared to WT. Like users of PPIs, these mice have elevated serum gastrin levels due to high gastric pH. We wanted to study whether elevated gastrin influences bone quality in these mice.Female KO and WT mice aged 6 week...

Prolyl hydroxylase 2 (PHD2) regulates hypoxia-inducible factor α (HIFα) transcription factors and thus, erythropoietin (EPO) production. Under normoxic conditions, HIFα is constantly inactivated through hydroxylation by PHD2. Due to the embryonic lethality of PHD2 knock-out mice, its precise role in erythropoiesis and tissue homeostasis has long remained unknown. Recently, we generated a conditional knock-out (cKO) mouse lacking PHD2 in EPO-producing cells. Thes...

Type 2 diabetes mellitus impairs bone quality and increases fracture risk. We showed that diabetic ZDF rats have low bone mass due to impaired osteoblastogenesis, which can be partially reversed with an intermittent parathyroid hormone 1–84 (PTH) therapy. It remains unclear, why PTH treatment does not fully restore osteoblast (OB) function in diabetic conditions. Here, we tested if high glucose (HG) conditions lead to a partial PTH resistance in osteoblasts. Pre-osteoblas...

While the importance of interactions between bone and tumors is well-established, the mechanism by which the physical bone microenvironment regulates disease progression is limited by the lack of suitable in vitro models. We have designed 3D Tissue Engineered Constructs (TECs) using microCT imaging in tandem with inkjet 3D printing technology that recapitulate the mechanical and morphometric properties of trabecular bone. 3D-printed TECs exhibited no significant diffe...

It is well established that tumor expression of Gli2, a Hedgehog family transcription factor, contributes to tumor-induced bone disease. Our previous studies investigating genetic inhibition of Gli2 expression in tumor cells have shown promise for the development of therapeutics. While many groups have focused on developing upstream Hedgehog inhibitors for soft-tissue tumors that aberrantly express Gli proteins, we have previously demonstrated that the expression of Gli2 in tu...

Biallelic ENPP1 deficiency in humans induces hypophosphatemic rickets in children characterized by increased circulating FGF23 levels and renal phosphate wasting (‘Autosomal Recessive Hypophosphatemic Rickets Type 2’, or ARHR2), but osteopenia or osteoporosis has not been described in adults. Here, we describe three adult male patients (ages 43, 59, and 62) suffering from early-onset osteoporosis who presented to the Institute of Osteology and Biomechanics at the Uni...

Introduction: Vitamin D is known to be important for bone health. Still, the significance of serum 25-hydroxy vitamin D concentrations (s-25OHD) for hip fracture risk of the elderly is uncertain. Discordant findings may in part be explained by difficulties of RCTs or large cohort studies to reach both the frail and the healthy elderly. The objectives of this study were to determine the risk of hip fractures of the elderly related to s-25OHD, including both the frail and the he...

The pathogenesis of skeletal fragility in diabetes mellitus is poorly defined and efficient therapies are limited. Zucker diabetic fatty (ZDF) rats with type 2 diabetes mellitus display low bone mass and delayed bone defect healing. We tested whether intermittent treatment with human parathyroid hormone 1–84 (PTH) increases bone mass and bone defect regeneration in diabetic rats.A subcritical gap defect was created at the femur of 10 weeks old diabe...

Diabetes mellitus results in increased skeletal fragility through reduced bone mineral density and altered collagen structure. How these changes affect bone mechanics at the tissue level remains largely unclear. Anti-osteoporosis medications improve bone mass, but whether they can fully restore tissue strength in diabetic bone, where collagen quality is compromised, has not been fully elucidated. The objective of this study was to determine the effect of type 2 diabetes mellit...