Cinalcalcet and bone mineral density in primary hyperparathyroidism with osteoporosis

Abstracts / Bone 48 (2011) S236–S245 Clinical bone pain was reduced after 3 month, but increased again to baseline at month 5. In this brief report, we have shown for the first time that the administration of 60 mg Denosumab treatment subcutaneous is an effective treatment for PDB over a period of 5 months. The treatment can be used in patients with low GFR and in the case of PDB. Bonespecific biomarkers will be analysed and presented. This article is part of a Special Issue entitled ECTS 2011. Disclosure of interest: P. Schwarz Advisory Board Membership of Lilly, Amgen, Speaker Fees from Lilly, Amgen, A. L. Lysgaard: none declared, T. Kvist: none declared, A. Rasmussen: none declared. doi:10.1016/j.bone.2011.03.586

PP456-T French guidelines for the management of fibrous dysplasia and Mccune Albright syndrome P. Orcel a,⁎, C. Rey-Jouvin b, V. Bousson c, M. Le Merrer d, G. Baujat d, R.D. Chapurlat e a Rheumatology, University Paris Diderot and APHP, Paris, France b Rheumatology, University Paris 6 and APHP, Paris, France c Radiology, University Paris Diderot and APHP, Paris, France d National Reference Centre on Congenital Bone and Joint Diseases, Necker University Hospital, Paris, France e National Reference Centre on Fibrous Dysplasia and McCune Albright Syndrome, Hopitaux de Lyon and Inserm, Lyon, France Abstract: Rationale: Fibrous dysplasia of bone (FDB) and McCune Albright syndrome (MCA) are rare diseases with no validated guidelines. This leads to misdiagnosis or delayed diagnosis and treatment and is detrimental to patients. The recent labelling of national reference centres (NRC) in France in the context of a Health Ministry plan on orphan diseases triggered this work on guidelines for the management of FDB and MCA. Methods: The French society for rheumatology together with three NRC endorsed a working group. A validated search strategy using 17 keywords or keyword groups through automated and other databases identified the relevant literature for the past 10 years. Four meetings of the working group have allowed a systematic review, the writing of a state of the art document and of a list of guidelines. Guidelines were reviewed and quoted by an independent committee. A final meeting of the working group finalized the recommendations. These documents have been sent to the Haute Autorité de Santé for final validation and official endorsement. Results: The literature search identified 567 articles, among which 179 have been selected, according to predefined criteria. The final list of 184 recommendations is developed in 4 chapters: diagnostic strategy according to the presenting symptoms (fortuitous radiologic image, bone pain, fracture or deformation, café-au-lait skin spots, precocious puberty, maxillofacial or skull involvement, muscle mass, place of the reference centres in the diagnosis, indications of bone biopsy and of molecular diagnosis), prognostic evaluation (extension of bone involvement and of metabolic or endocrine manifestations in children and in adults, evaluation of neurosensory and maxillofacial involvement, evaluation of the disability and psychological impact), therapeutic recommendations (indications of bisphosphonates, indications of various types of surgery, treatment of endocrine diseases, psychological and social support), and follow-up of the patient. Conclusions: The management guidelines should help in the improvement of the quality of the clinical management of patients suffering from FDB and/or MCA. The central position of the NRC is emphasized for a crucial role in the diagnostic and therapeutic strategy, especially in facilitating access to bisphosphonates, guiding the global long term management of the patients, and organizing further research efforts to develop new and validated treatments and improve our understanding of the disease. This article is part of a Special Issue entitled ECTS 2011. Disclosure of interest: P. ORCEL Grant / Research Support from Warner Chilcott, Lecture Fees from Amgen, Merck, Servier, Warner Chilcott, C. REY-JOUVIN: none declared, V. BOUSSON: none declared, M. LE MERRER: none declared, G. BAUJAT: none declared, R. CHAPURLAT: none declared.

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Department of Medical Biophysics, Sunnybrook Health Sciences Centre, Toronto, Canada d Australian Craniofacial Unit, Women's and Children's Hospital, Adelaide, Australia Abstract: Craniosynostosis, the premature bony fusion of one or more of the skull sutures, is a disfiguring abnormality of infancy and childhood, affecting one in 2500 live births. We have discovered that glypican 3 (GPC3), a heparan sulphate proteoglycan, is down regulated during premature suture fusion [1]. Given that glypicans can regulate growth factor signalling and that the bone morphogenetic protein (BMP) pathway has a crucial role in skull development, we propose that reduced levels of GPC3 are a possible cause of suture fusion in craniosynostosis. Here we investigated the function of GPC3 on BMP signalling and osteogenesis in cultured human primary cranial suture cells. GPC3 contains a glycosyl-phosphatidylinositol (GPI) anchor sequence that enables it to position on the cell surface where it can act as a co-receptor for growth factors. On cleavage, it can also be released into the extracellular environment. Using confocal microscopy and flow cytometry we demonstrate that GPC3 is localized at the cell surface and intracellularly in cultured human cranial suture cells. We also show that GPC3 is present extracellularly. Transient transfection analyses of GPC3 expression vectors and a BMP-responsive promoter-reporter demonstrate that the BMP pathway is repressed by ectopic expression of GPC3. Furthermore, recombinant GPC3 represses BMP2 activity in a dose-dependent manner and blockade by GPC3 antibody increases BMP2 activity. We conclude from these data that soluble GPC3 is an antagonist of BMP2 activity in human suture cells and we predict that the down-regulation of GPC3 we have observed in sutures increases BMP2 activity and causes increased osteogenesis of the suture. This article is part of a Special Issue entitled ECTS 2011. Disclosure of interest: None declared. Reference

[1] Coussens AK, Wilkinson CR, Hughes IP, Morris PC, Dall AV, Anderson PJ, Powell BC. Unravelling the molecular controls of calvarial suture fusion in children with craniosynostosis. BMC Genomics 2007;8:458. doi:10.1016/j.bone.2011.03.588

PP458-M Decreased vitamin D is linked to increased fracture risk in non-osteoporotic patients — Case series study S. Sokolovic ⁎ Rheumatology, University Clinical Center Sarajevo, Sarajevo, Bosnia and Herzegovina Abstract: Background: The Vitamin D and its metabolites have a great impact on the bone quality and biomechanics. Decreased values in sera can promote and contribute to increased bone fracture risk and also to promote autoimmunity process. In combination with calcium and magnesium, vitamin D is essential in the osteoporosis therapy and in its prevention. Objective: The goal of this paper was to present the case series of 17 patients with normal Body Mass Index (BMI) who suffered the first bone fracture and level of vitamin D in such patients. Methods: The clinical case series study was conducted in order to evaluate the vitamin D sera levels with presumed normal bone structure. Vitamin D levels were measured following the unexpected fracture in the radius and tibia. All demographics including BMI and BMD test were done on each subject. The inclusion criteria were patients with normal or mild osteopenia who suffered the fracture. Results: In all 17 patients, no osteoporosis was linked to fracture. All 17 cases had normal BMD test values or mild osteopenia. The vitamin D sera levels were found in all 17 patients and sera severe levels were associated with more fracture complications and longer duration of rehabilitation and hospitalisation. Conclusion: Despite normal BMI and normal BMD or mildly decreased, all patients suffered the bone fracture on unexpected minor falls. Vitamin D was decreased in all subjects and it was found in our case series study to be another fracture risk factor. This article is part of a Special Issue entitled ECTS 2011. Disclosure of interest: None declared. doi:10.1016/j.bone.2011.03.589

doi:10.1016/j.bone.2011.03.587

PP457-S Regulation of bone morphogenetic protein signalling and osteogenesis by glypicans in human cranial suture cells P.P. Dwivedi a,⁎, R.H. Grose a, C.S. Hii b, J. Filmus c, P.J. Anderson d, B.C. Powell a a Craniofacial Research Group, Women's and Children's Health Research Institute, Adelaide, Australia b Department of Immunology, Women's and Children's Hospital, Sa Pathology, Adelaide, Australia

PP459-T Cinalcalcet and bone mineral density in primary hyperparathyroidism with osteoporosis S. Vai a,⁎, A. Dubini a, L. Persani a,b, M.L. Bianchi a a Bone Metabolism Unit, Istituto Auxologico Italiano IRCCs, Milano, Italy b Dipartimento di Scienze Mediche, Università di Milano, Milano, Italy Abstract: Primary hyperparathyroidism (PHPT) is a common endocrine disorder, affecting 0.3% of the general population, and 1–3% of postmenopausal women. Decreased bone density and increased fracture risk have been reported. Chronic PTH excess leads to increased bone resorption. Surgery is the recommended treatment, but for those with

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contraindications, a specific pharmacologic agent is now available. Cinacalcet is a calciumsensing receptor agonist that has proven effective in reducing serum calcium and PTH levels. Few data on its long-term effects on bone metabolism and BMD are available, and our study was aimed at investigating such effects with cinacalcet alone (30 mg twice/day). We are now presenting preliminary data (all expressed as the mean ± SD) on 15 patients (out of 20 enrolled), who completed their first 12 months of treatment with cinacalcet. All were postmenopausal women affected by PHPT and with spine and hip BMD T-score ≤ − 2.5. Mean age 69.3 ± 7.7 years (range 57–82); age at menopause 48.1 ± 4.9 years. Bone metabolism was periodically evaluated, and BMD was measured at baseline and after 12 months of therapy. Spine, hip, forearm and total body (TB) BMD were measured with DXA (Hologic). As expected, serum calcium (total and ionized) decreased rapidly: total calcium decreased from 10.7 ±0.4 mg/dl at baseline to 9.1 ± 0.7 ng/ml after 15 days (p< 0.01). Calcium level was maintained within normal range until the end of the 12-month treatment (9.04 ± 0.7 mg/dl). PTH decreased with respect to baseline, then remained stable until the end of the 12-month treatment: at baseline 138± 45.2 pg/dl, at 12 months 110 ± 32.5 pg/dl (p< 0.02). Serum 25-OH vitamin D levels were within normal range throughout the study. Bone resorption markers (CTx and NTx) were slightly increased at baseline and did not change significantly. No statistical difference was observed regarding BMD at all the 4 skeletal sites.

BMD T-score

baseline (enrollment)

after 12 months (cinacalcet therapy)

T-score spine T-score total HIP T-score TB T-score forearm

–2.5 ± 1.3 –2.5 ± 0.6 –2.7 ± 0,8 –3.5 ± 1.2

–2.6 ± 1.4 –2.6 ± 0.6 –2.9 ± 0,8 –3.7 ± 1.1

We can conclude that cinacalcet treatment in post-menopausal women affected by HPTH and osteoporosis was able to normalize calcemia, control PTH increase, maintain bone turnover and avoid significant further decreases in BMD (both trabecular and cortical). The study was possible thanks to the support of Amgen Dompé Italy, who supplied the drug when it was not yet approved for HPTH in Italy. This article is part of a Special Issue entitled ECTS 2011. Disclosure of interest: None declared. doi:10.1016/j.bone.2011.03.590

PP460-S Differences in fat and bone metabolism between genders are partially mediated by the P2X7 receptor S. Petersen a,⁎, S. Syberg b, M. Riis c, P. Schwarz a, N.R. Joergensen c a Research Center for Ageing and Osteoporosis, Copenhagen University Hospital Glostrup, Glostrup, Denmark b Research Center for Ageing and Osteoporosis, Research Centre for Ageing and Osteoporosis, Glostrup, Denmark c Department of Clinical Biochemistry, Copenhagen University Hospital Glostrup, Glostrup, Denmark Abstract: The purinergic P2X7 receptor (P2RX7) is an ATP-gated cation channel that is expressed in many cells, including osteoblasts. It has important functions in regulation of bone formation and turnover. As osteoblasts share common precursors with the adipocyte cell line, P2RX7 may be involved not only in regulation of bone metabolism but also in commitment of cells to the two lineages and to regulation of fat metabolism. Therefore, the aim of this study was to investigate the role of the P2X7 receptor in gender-related differences in fat and bone metabolism. Forty-two Balb/cJ mice were sacrificed at age 16 weeks. Of these 19 were wild type (WT) (9 males and 10 females) and 23 P2RX7 −/− (KO) (11 males and 12 females). Serum was collected for measurement of adiponectin and leptin, and bone marrow from the tibia and femur was collected for determination of expression of bone and fat related genes (genes for osteocalcin (BGP), alkaline phosphatase (ALPL), collagen type 1 (COL1A1), RUNX2 and PPAR-gamma). Adiponectin and leptin levels were compared between genders. For the WT animals, differences were detected for both markers with females having higher values (Adiponectin mean (+/−SEM): females: 72.0 μg/ml (+/−3.3) vs. males 19.5 μg/ml (+/−4.1); p<0.001; Leptin: females: 1.8 ng/ml (+/−0.3) vs. 0.6 ng/ml (+/−0.1); p<0.013). In bone marrow, expression of genes related to bone formation and osteoblast differentiation were significantly increased by a factor two or more in females compared to males. Also the expression of PPAR-gamma was higher in females, though expression was only increased by 70%. To determine the role of P2RX7 in the gender-related differences, we compared adiponectin and leptin values between genders in the KO animals. Now, only adiponectin levels were significantly different between genders, with the numeric difference being less than in the WT animals (females: 63.4 μg/ml (+/−1.5) vs. males: 27.8 μg/ml (+/−3.2); p< 0.001). For gene expression, only differences were found for RUNX2, and again the numeric difference between genders was decreased compared to WT. In conclusion, levels of circulating markers of fat metabolism are different between males and females, and this difference seems to be partially contributable to P2RX7. Also, expression of genes related to bone formation, and osteoblast and adipocyte differentiations in bone marrow are significantly different between genders, and again P2RX7 expression is partially responsible for this difference.

This article is part of a Special Issue entitled ECTS 2011. Disclosure of interest: None declared. doi:10.1016/j.bone.2011.03.591

PP461-M Renal osteodistrophy in chronic renal disease in rat T. Celic a,⁎, J. Spanjol b, A. Grskovic b, D. Markic c, I. Maric a, D. Bobinac a Department of Anatomy, Faculty of Medicine, University of Rijeka, Rijeka, Croatia b Department of Urology, Clinical Hospital Rijeka, Rijeka, Croatia c Department of Urology, Faculty of Medicine, University of Rijeka, Rijeka, Croatia

a

Abstract: Receptor activator of nuclear factor-kappaB ligand (RANKL) is newly identified molecule that contributes to the modulation of bone remodeling. In chronic renal failure, the cytokine systems involved in the regulation of bone turnover may be influenced, and are therefore likely to contribute to the pathogenesis of renal bone disease. The aim of the present study was the evaluation of RANKL in concert with bone serum markers in rats with induced end stage renal disease (ESRD) and correlation with bone histomorphometric changes. The rats undergone to 5/6 nephrectomy and three months later were sacrificed. We measured serum levels of intact PTH (iPTH), osteocalcin (OC), and tartrate-resistant acid phosphatase (TRAP) in 30 ESRD rats and in 15 healthy controls. The whole femur was taken out from the body. Bone histomorphometry was determined by micro-CT. Bones were decalcified in 10% EDTA solution, embedded in paraffin and immunohistochemistry was performed. We determined in bone tissue alkaline phosphatase and TRAP enzyme activity as well as the RANKL expression. The average serum OC level was lower, whereas the average serum concentration of TRAP was higher in ESRD rats than in healthy controls. ESRD in all rats did not affect increase of iPTH. The expression of RANKL did not correlate with iPTH levels. The alkaline phosphatase and TRAP positive cells in the bone marrow and trabecular surface were decreased in ESRD rats. The RANKL expression decreased also in bone marrow stromal osteoblasts. All bone histomorphometric parameters confirmed loss of bone tissue. This article is part of a Special Issue entitled ECTS 2011. Disclosure of interest: None declared. doi:10.1016/j.bone.2011.03.592

PP462-T Age dynamics of chemical compositions into bone reclaim in conditions streptozotocin-induced diabetes V. Luzin ⁎, A. Ivchenko, A. Lubenets State Medical University, Luhansk, Ukraine Abstract: Aim of the study: Research dynamics of chemical composition in to bone reclaim which formed in tibia defect zone at rats with streptozotocin-induced diabetes. Materials and methods: Researched 240 white rats-males, 2 age groups: reproductive animals and rats with age-related changes. Also all animals were divided in four groups: 1st group — intact animals, 2nd group rats with formed 2.2 mm bone defect at the border between proximal metaphyseal part and diaphysis of the tibia. 3rd group is formed by rats with streptozotocin-induced diabetes. In 4th group rats also had tibia defect as in 2nd group and streptozotocin-induced diabetes. After expiry of the experiment terms (7–180 days), bone fragments which appropriate to the defect, were separated and researched by weighing method. Results and discussions: At the intact reproductive animals content of the water and organic component was decreasing in all observed periods. The mineral part was increasing all time. In period of age-related changes up to 60 days observations content of the water and organic component was also decreased, but part of mineral component was increased. After 90 days, as result of senile osteoporosis was observed there were increased water content and decreased mineral content. In 2nd group (tibia defect) at reproductive animals from 7 to 60 days observed water content in reclaim was more than in the 1st group. Mineral part was lesser, than in the 1st group. Part of the organic component was more increased after 60 days than in the 1st group. In 2nd group, rats with senile changes, have changes in water and mineral contents similar with reproductive animals, but deviation amplitude was higher. Reproductive rats with tibia defect and streptozotocin-induced diabetes from 15 to 90 days had increased water content in to reclaim. The organic and mineral parts in this period were lesser than in 1st group. In age-related change period water content increased all time. Mineral and organic contents were lesser than in 1st group in all experiment time. Conclusion: Thus in streptozotocin-induced diabetes conditions, reproductive animals and rats with age-related changes, have imbalance in chemical compositions into bone reclaim. These changes indicated decelerations of bone reparative regeneration process. Dynamics and degree of this deviations depended from animals' age. This article is part of a Special Issue entitled ECTS 2011. Disclosure of interest: None declared. doi:10.1016/j.bone.2011.03.593