Bone Abstracts

The aim of the study was to evaluate effects of 6-month-long administration with nanopartical calcium on morphological and densitometric properties of axial skeleton in pigs subjected to osteoporosis induction with dexamethasone. Male newborn piglets (N=28) were divided after birth into four equal groups (control group receiving placebo, Dex group receiving dexamethasone, NanoCa group receiving orally nanopartical calcium and NanoCa/Dex group) receiving simultaneously...

The aim of this study was to determine morphological and densitometric parameters of mandible obtained from male and female silver foxes (Vulpes vulpes). The study was performed on 1-year-old males (n=7) and females (n=8). Mandible was isolated and subjected to morphological and densitometric analysis using quantitative computed tomography (QCT) method and Somatom Emotion Siemens apparatus (Siemens, Erlangen, Germany) equipped with Somaris/5 VB10B so...

Objectives: Hypophosphatasia (HPP) is a rare hereditary disease, leading to deficits in bone and tooth mineralization, muscular as well as neurological abnormalities due to decreased enzymatic activity of the tissue-nonspecific alkaline phosphatase (TNAP, encoded by the alpl gene). In this project, the zebrafish (Danio rerio) will be established as a new and valuable animal model for HPP research. Consequently, endogenous TNAP expression should be analyzed in different zebrafi...

Objectives: Mice with a non-functioning vitamin D receptor (VDR mutants) develop severe secondary hyperparathyroidism, which can be rescued by a diet enriched with calcium, phosphate and lactose. In this work, we studied the effects of a low calcium challenge (CD), normal calcium (ND) and a calcium enriched rescue diet (RD) on the bone mineralization density distribution (BMDD) and osteocyte lacunae sections (OLS) in these mice.Methods: BMDD and OLS were...

Preclinical and epidemiologic data suggest that vitamin D deficiency may play a role in the pathogenesis and progression of prostate cancer. Based on recently reported genetic determinants of vitamin D insufficiency we investigated a functional T>G single nucleotide polymorphism (SNP) in the group-specific component (GC) gene for its association with 25-hydroxy (25-OH) vitamin D and 1.25 dihydroxy (1.25-OH) vitamin D levels and further to test a possible association with m...

Background and methods: A specific skeletal complication in children with CKD is growth impairment. The effects of recombinant human growth hormone (rhGH) therapy on bone turnover and bone material quality are not well understood. Bone matrix mineralization density distribution (BMDD) as assessed by quantitative backscattered electron microscopy (qBEI) is an important determinant of bone material quality and reflects bone turnover (average tissue age) and mineralization kineti...

Acute phase reaction (APR) is the most frequent side effect following i.v. nitrogen-containing bisphosphonates (N-BPs) infusion. A recent observation in osteoporotic women treated with N-BPs evidenced a negative association between 25(OH)D levels and APR, likely due to the immuno-modulatory effects of vitamin D on γδTcells. However, this association remains to be demonstrated in patients with Paget’s disease of bone (PDB). Moreover whether vitamin D supplementat...

Defects in 24-hydroxylation caused by vitamin D-hydroxylase (CYP24A1) loss-of-function mutations lead to decreased degradation of 1,25(OH)2D and the syndrome of idiopathic infantile hypercalcemia. Affected individuals show increased sensitivity to vitamin D and may develop severe hypercalcemia and hypercalciuria, even with small doses of vitamin D.Presenting: The objective of the study was to investigate the gene expression profile in...

Transient receptor potential vanilloid channels (TRPVs) have been implicated in Ca2+ homeostasis and bone metabolism. In particular, TRPV4 deficiency was shown to cause sexual dimorphism in bone metabolism and osteoporotic fracture risk. Cortical bone structure was reported to be altered in male TRPV4 knock-out (TRPV4−/−) mice but not in female TRPV−/− mice compared to sex-matched wildtype (TRPV4+/+) animals.To gain knowledge on t...

Pathophysiological calcification in the vasculature favours cardio- and cerebrovascular diseases. In patients with chronic kidney disease vitamin K metabolites are associated with decreased vascular calcification.We investigated the expression of vitamin K dependent proteins (VKDPs) in vessels and bone to identify differences in expression pattern during atherosclerosis (AS) stages and compare the two tissue profiles.Gene expressio...