Bone Abstracts

see P58....

There have been considerable advances in our knowledge of how loss of androgens signalling leads to bone loss in aging male with hypogonadism. However, the roles of androgen actions on the skeletal growth remain limited. Recently, new insights into the function of and androgen receptor (AR), learned from human genetic mutations and gene targeting mouse models have contributed to emerged understanding of the androgenic effects on bone and cartilage in health and diseases. Here,...

We previously elucidated that β-adrenergic blockade attenuates high fat diet induced obesity development and such an effect is associated with suppressed pancreatic lipase (PNLIP) expressions. In the present study, we tested whether β-adrenergic blockade downregulates bioactive osteocalcin secretion in osteoblasts, thereby reduces PNLIP secretion in pancreatic acinar cells.Forty of male 6wk old C57BL/6 mice were assigned into control diet (CON)...

Mechanical stress and strain generated by physical exercises or the other passive stimulations are well known to have a positive effect on the growing musculoskeletal system. Especially, when the impact stimulation which evokes high magnitude of strain in a second is applied to bone, it improves bone qualities. Thus, to verify the effect of impact stimulation, we conducted longitudinal study on morphological properties of the tibia in growing rats. Free falls from designated h...

Limb length discrepancy has been observed in children with hemiplegic cerebral palsy (HCP). However, the difference of bone age and limb lengths have been a controversial issue. The purpose of this study was to analyze the bone age and the upper extremity segmental lengths between affected and naffected in HCP patients.Seventy-eight patients (39 boys and 39 girls; mean age 71.3±28.1 months). Fourty-five children were right and 33 were left hemiplegi...

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...

Objective: Cystinosis is a rare lysosomal storage disorder caused by loss-of-function mutations of the CTNS gene, encoding for cystinosin symporter that mediates cysteine efflux from lysosome. ~95% of cystinotic patients display nephropathic Fanconi’s syndrome, short stature, osteopenia and rickets. In this study we evaluated whether the absence of cystinosin primarily affects bone remodeling activity.Methods: We analyzed bone phen...

Osteoclast-poor RANKL-dependent autosomal recessive osteopetrosis (ARO) is a rare bone disease characterized by an increase in bone density due to the failure of bone resorption by impaired osteoclast formation. Haematopoietic stem cell transplantation is not an effective therapy for this ARO form, since in bone RANKL is produced mainly by cells of mesenchymal origin. Whether also these cells, besides the osteoclast, are in some way affected by RANKL deficiency is not known. T...

The osteoclast-associated receptor (OSCAR), primarily described as a co-stimulatory regulator of osteoclast differentiation, represents a novel link between bone metabolism and vascular biology. Previously, we identified OSCAR on endothelial cells responding to the proatherogenic factor oxidized low density lipoprotein (oxLDL). Additionally, OSCAR expression was increased in the aorta of atherogenic apoE-knock-out (apoE-KO) mice, where it was further induced by feeding a high-...

Pparγ is a master transcriptional regulator of energy metabolism. We demonstrated that Dmp1-Cre/Lox-mice (KO) have increased bone mass and improved energy metabolism. Here we investigated if Pparγ-deficiency in Dmp1 cells can prevent high fat diet effects on these parameters. For this purpose, WT and KO male mice aged of 16 weeks received a high fat or chow diet (HF 60% vs CD 10% of fat) for 12 weeks. Lean and fat, bone structure, metabolic rate and tissue temperatur...