Bone Abstracts

Dipeptidyl peptidase 4 (DPP4) modulates activity of proteins by removing two aminoterminal amino acids. DPP4 inhibitors are currently being used to improve glucose tolerance in type 2 diabetes patients by increasing the half-life of DPP4 substrates. It has been shown that these substrates do not only increase pancreatic insulin secretion, but also influence bone cell activity. The potential therapeutic effect of DPP4 inhibition on bone metabolism is thus worth being investigat...

Introduction: The RANKL/RANK/OPG system has a key role in bone metabolism. Beyond its role in bone loss, its importance was also documented during inflammation which occurrs in inflammatory bowel disease (IBD). The aim of this study was to investigate the expression of the receptor activator of NF-κB ligand (RANKL) and its receptors RANK as well as its decoy receptor osteoprotegerin (OPG) in the colon during experimantal IBD and following BMP7 or corticosteroid therapy.</...

Conventional treatment of hypoparathyroidism with calcium and active vitamin D analogues causes a high renal calcium excretion and over-mineralized bone.We studied 62 patients with hypoPT randomized to 6 months of treatment with either parathyroid hormone (PTH(1-84)) 100 μg/d s.c. or similar placebo, administered as an add-on therapy. Forty-two of the patients had follow-up test performed after 2.5 years; 9 patients had continued daily PTH treatment...

Introduction: The etiology of Paget’s disease of bone (PDB) is not fully understood, but genetic factors play a clearly important role. Single nucleotide polymorphisms (SNPs) of OPTN gene within PDB6 locus have been highly associated with PDB, but no PDB causal mutation or functional effect on PDB development were reported to date. We aimed to identify functional SNPs associated with this bone disease.Methods: Relevant candidate genes from PDB6 locu...

Purpose: Osteoradionecrosis (ORN) of the mandible is a serious complication of radiation therapy, and preceded by soft tissue damage before bone loss appears. However, there is still no adequate treatment to heal the soft tissue damage of ORN. This study investigated the effect of PDGF-BB or mesenchymal stem cells (rMSCs) on radiation-induced soft tissue injury.Methods: Rat model was designed to irradiate the skin of SD rats while sparing the body and in...

Background: High zoledronic acid (ZOL) dose protocol, one of the most potent inhibitors of bone resorption, is currently evaluated in a phase III clinical trial in Europe for the treatment of malignant pediatric primary bone tumors. The impact of such an intensive treatment on the craniofacial skeleton growth is a critical question in the context of patients with actively growing skeleton, in the light of our previous studies evidencing that endochondral bone formation was tra...

Objectives: CKD in children is associated with suppressed body growth. Physical activity has been previously shown to increase expression of IGF1 signaling in muscles of rats with CKD, but the effects of this intervention on bone tissue have not been investigated yet. The purpose of this study was to examine the effects of aerobic exercise on CKD related bone disease.Methods: Twenty-day old/50 g male rats underwent a two step subtotal nephrectomy (Nx) or...

The chronic use of glucocorticoids in patients with congenital adrenal hyperplasia (CAH) may result in decreased bone mass. Therefore, using simple and accurate methods for assessing bone status in these patients could facilitate the treatment of disease. The purpose of this study was to verify the association between parameters of bone mass measured by dual energy X-ray absorptiometry (DXA) and quantitative ultrasound (QUS) of proximal phalanges in children adolescents with c...

Objectives: Lysophosphatidic acid (LPA) is a potent lipid growth factor which possess several G protein-coupled receptors LPA1-6. We have recently demonstrated that LPA1 receptor-invalidated mice display abnormal bone development and osteoporosis, suggesting abnormal endochondral ossification. We have here further studied the growth plates of LPA1 receptor-invalidated mice.Methods: We performed a microscopic and immuno-histochemistry analysis of the femo...

Objectives: Ghrelin is a peptide hormone secreted in the stomach, which stimulates GH release and food intake. It is also known to have an effect on bone metabolism. The ghrelin specific receptor, GHS-R1a, belongs to the G protein-coupled receptors (GPCRs). Its downstream pathway in osteoblasts remains unclear. We attempted to clarify the way by which ghrelin acts on osteoblast differentiation.Methods: We studied two human osteosarcoma cell lines, MG63 a...