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Pinto B, Muzumdar R, Hecht Baldauff N. Bone health in children undergoing solid organ transplantation. Curr Opin Pediatr 2023; 35:703-709. [PMID: 37811914 DOI: 10.1097/mop.0000000000001290] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/10/2023]
Abstract
PURPOSE OF REVIEW Pediatric solid organ transplant recipients are a unique and growing patient population who are at risk for metabolic bone disease both before and after transplantation. RECENT FINDINGS The odds of sustaining a fracture in adulthood are significantly higher if an individual has sustained at least one childhood fracture, therefore, close monitoring before and after transplant is essential. Emerging data in patients with chronic kidney disease mineral and bone disorder (CKD-MBD) and hepatic osteodystrophy highlights the role of fibroblast growth factor 23 in the pathogenesis of metabolic bone disease in these conditions. While dual X-ray absorptiometry (DXA) is the most widely used imaging modality for assessment of bone mass in children, quantitative computer tomography (QCT) is an emerging modality, especially for patients with glucocorticoid-induced osteoporosis. SUMMARY Solid organ transplantation improves organ function and quality of life; however, bone mineral density can decline following transplantation, particularly during the first three to six months. Immunosuppressive medications, including glucocorticoids, are a major contributing factor. Following transplant, treatment should be tailored to achieve mineral homeostasis, correct nutritional deficiencies, and improve physical conditioning. In summary, early identification and treatment of metabolic bone disease can improve the bone health status of pediatric transplant recipients as they enter adulthood. VIDEO ABSTRACT http://links.lww.com/MOP/A71.
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Affiliation(s)
- Bianca Pinto
- UPMC Children's Hospital of Pittsburgh, Pittsburgh, Pennsylvania, USA
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Kubota M, Hamasaki Y, Hashimoto J, Aoki Y, Kawamura T, Saito A, Yuasa R, Muramatsu M, Komaba H, Toyoda M, Fukagawa M, Shishido S, Sakai K. Fibroblast growth factor 23-Klotho and mineral metabolism in the first year after pediatric kidney transplantation: A single-center prospective study. Pediatr Transplant 2023; 27:e14440. [PMID: 36471536 DOI: 10.1111/petr.14440] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/27/2022] [Revised: 10/27/2022] [Accepted: 10/28/2022] [Indexed: 12/12/2022]
Abstract
BACKGROUND The role of fibroblast growth factor 23 (FGF23) levels in mineral metabolism before and after kidney transplantation in pediatric patients is poorly understood. METHODS We prospectively evaluated 24 patients under 18 years of age (4.5 [3.3-9.8] years) who underwent living kidney transplantation between July 2016 and March 2018, and measured intact FGF23 and serum αKlotho levels, and other parameters of mineral metabolism before and after transplantation (Day 7, 1 and 4 months, and 1 year). Relationships between parameters were examined by linear analysis. RESULTS FGF23 level was 440.8 [63.4-5916.3] pg/ml pre-transplant and decreased significantly to 37.1 [16.0-71.5] pg/ml at Day 7 post-transplant (-91.6%, p < .001). Thereafter, it remained at normal levels until 1 year. αKlotho level was 785 [568-1292] pg/ml pre-transplant and remained low at Day 7 and 1 month post-transplant, with an increasing trend at 4 months. Post-transplant phosphorus levels were significantly decreased compared with pre-transplant, with a lowest level of 1.7 [1.3-2.9] mg/dl, -5.7 [-6.8, -3.8] SD at Day 4, followed by gradual recovery. Phosphorus levels and the ratio of tubular maximum phosphate reabsorption were significantly and negatively associated with pre-transplant FGF23 until 4 months of post-transplant. Pre-transplant αKlotho was negatively associated with pre-transplant FGF23 but not FGF23 or other parameters after transplantation. CONCLUSION FGF23 in pediatric kidney transplant patients decreased rapidly after transplantation and associated with post-transplant hypophosphatemia and increased phosphorus excretion. Post-transplant αKlotho was low early post-transplant but tended to increase subsequently. Post-transplant αKlotho was unaffected by pre-transplant FGF23 or other factors, suggesting pre-transplant chronic kidney disease status has no effect.
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Affiliation(s)
- Mai Kubota
- Department of Nephrology, Toho University, Faculty of Medicine, Tokyo, Japan
| | - Yuko Hamasaki
- Department of Nephrology, Toho University, Faculty of Medicine, Tokyo, Japan
| | - Junya Hashimoto
- Department of Nephrology, Toho University, Faculty of Medicine, Tokyo, Japan
| | - Yujiro Aoki
- Department of Nephrology, Toho University, Faculty of Medicine, Tokyo, Japan
| | - Takeshi Kawamura
- Department of Nephrology, Toho University, Faculty of Medicine, Tokyo, Japan
| | - Akinobu Saito
- Department of Nephrology, Toho University, Faculty of Medicine, Tokyo, Japan
| | - Rena Yuasa
- Department of Nephrology, Toho University, Faculty of Medicine, Tokyo, Japan
| | - Masaki Muramatsu
- Department of Nephrology, Toho University, Faculty of Medicine, Tokyo, Japan
| | - Hirotaka Komaba
- Division of Nephrology, Endocrinology and Metabolism, Tokai University School of Medicine, Isehara, Japan
| | - Masao Toyoda
- Division of Nephrology, Endocrinology and Metabolism, Tokai University School of Medicine, Isehara, Japan
| | - Masafumi Fukagawa
- Division of Nephrology, Endocrinology and Metabolism, Tokai University School of Medicine, Isehara, Japan
| | - Seichiro Shishido
- Department of Pediatric Nephrology, Toho University, Faculty of Medicine, Tokyo, Japan
| | - Ken Sakai
- Department of Nephrology, Toho University, Faculty of Medicine, Tokyo, Japan
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Picard S, Mayemba CN, Ung RV, Martel S, Mac-Way F. Division of an Iliac Crest Bone Biopsy Specimen to Allow Histomorphometry, Immunohistochemical, Molecular Analysis, and Tissue Banking: Technical Aspect and Applications. JBMR Plus 2020; 4:e10424. [PMID: 33354645 PMCID: PMC7745880 DOI: 10.1002/jbm4.10424] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/17/2020] [Revised: 09/25/2020] [Accepted: 10/05/2020] [Indexed: 11/25/2022] Open
Abstract
The evaluation of bone complications in chronic kidney disease (CKD) often requires a bone biopsy, the analysis of which can refine the diagnosis of bone defects. Bone histomorphometry performed on sections of the iliac crest biopsy remains the reference procedure for the quantitative assessment of bone health in CKD patients, whereas immunohistochemistry and other molecular biology analyses are indispensable tools for studying the disrupted signaling pathways. Traditionally, the whole iliac crest biopsy was included in methyl‐methacrylate (MMA) and was exclusively used for bone histomorphometry to describe static, dynamic, and structural parameters. Therefore, further molecular analysis of the bone tissue or the need for tissue banking would require a second biopsy to be made, because inclusion in MMA prevents the extraction of good‐quality nucleic acids. In this work, we describe a simple approach to divide a single iliac crest bone biopsy into multiple parts. This allows for simultaneous assessments of histology, immunohistochemistry, biomolecular analysis, and tissue banking while preserving the same bone surface area for histomorphometry. © 2020 American Society for Bone and Mineral Research © 2020 The Authors. JBMR Plus published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research.
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Affiliation(s)
- Sylvain Picard
- Centre Hospitalier Universitaire (CHU) de Québec Research Center, L'Hôtel-Dieu de Québec Hospital, Endocrinology and Nephrology Axis, Faculty and Department of Medicine Université Laval Quebec City Quebec Canada
| | - Christian N Mayemba
- Centre Hospitalier Universitaire (CHU) de Québec Research Center, L'Hôtel-Dieu de Québec Hospital, Endocrinology and Nephrology Axis, Faculty and Department of Medicine Université Laval Quebec City Quebec Canada
| | - Roth-Visal Ung
- Centre Hospitalier Universitaire (CHU) de Québec Research Center, L'Hôtel-Dieu de Québec Hospital, Endocrinology and Nephrology Axis, Faculty and Department of Medicine Université Laval Quebec City Quebec Canada
| | - Simon Martel
- Centre Hospitalier Universitaire (CHU) de Québec Research Center, L'Hôtel-Dieu de Québec Hospital, Endocrinology and Nephrology Axis, Faculty and Department of Medicine Université Laval Quebec City Quebec Canada
| | - Fabrice Mac-Way
- Centre Hospitalier Universitaire (CHU) de Québec Research Center, L'Hôtel-Dieu de Québec Hospital, Endocrinology and Nephrology Axis, Faculty and Department of Medicine Université Laval Quebec City Quebec Canada
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4
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Gitomer B, Pereira R, Salusky IB, Stoneback JW, Isakova T, Cai X, Dalrymple LS, Ofsthun N, You Z, Malluche HH, Maddux F, George D, Torres V, Chapman A, Steinman TI, Wolf M, Chonchol M. Mineral bone disease in autosomal dominant polycystic kidney disease. Kidney Int 2020; 99:977-985. [PMID: 32926884 DOI: 10.1016/j.kint.2020.07.041] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2020] [Revised: 06/23/2020] [Accepted: 07/16/2020] [Indexed: 01/09/2023]
Abstract
Mice with disruption of Pkd1 in osteoblasts demonstrate reduced bone mineral density, trabecular bone volume and cortical thickness. To date, the bone phenotype in adult patients with autosomal dominant polycystic kidney disease (ADPKD) with stage I and II chronic kidney disease has not been investigated. To examine this, we characterized biochemical markers of mineral metabolism, examined bone turnover and biology, and estimated risk of fracture in patients with ADPKD. Markers of mineral metabolism were measured in 944 patients with ADPKD and other causes of kidney disease. Histomorphometry and immunohistochemistry were compared on bone biopsies from 20 patients with ADPKD with a mean eGFR of 97 ml/min/1.73m2 and 17 healthy individuals. Furthermore, adults with end stage kidney disease (ESKD) initiating hemodialysis between 2002-2013 and estimated the risk of bone fracture associated with ADPKD as compared to other etiologies of kidney disease were examined. Intact fibroblast growth factor 23 was higher and total alkaline phosphatase lower in patients with compared to patients without ADPKD with chronic kidney disease. Compared to healthy individuals, patients with ADPKD demonstrated significantly lower osteoid volume/bone volume (0.61 vs. 1.21%) and bone formation rate/bone surface (0.012 vs. 0.026 μm3/μm2/day). ESKD due to ADPKD was not associated with a higher risk of fracture as compared to ESKD due to diabetes (age adjusted incidence rate ratio: 0.53 (95% confidence interval 0.31, 0.74) or compared to other etiologies of kidney disease. Thus, individuals with ADPKD have lower alkaline phosphatase, higher circulating intact fibroblast growth factor 23 and decreased bone formation rate. However, ADPKD is not associated with higher rates of bone fracture in ESKD.
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Affiliation(s)
- Berenice Gitomer
- Division of Renal Diseases and Hypertension, University of Colorado Denver Anschutz Medical Campus, Aurora, Colorado, USA
| | - Renata Pereira
- Department of Pediatrics, David Geffen School of Medicine at UCLA, Los Angeles, California, USA
| | - Isidro B Salusky
- Department of Pediatrics, David Geffen School of Medicine at UCLA, Los Angeles, California, USA
| | - Jason W Stoneback
- Department of Orthopedics, University of Colorado Denver Anschutz Medical Campus, Aurora, Colorado, USA
| | - Tamara Isakova
- Division of Nephrology and Hypertension, Department of Medicine, Center for Translational Metabolism and Health, Institute for Public Health and Medicine, Northwestern University Feinberg School of Medicine, Chicago, Illinois, USA
| | - Xuan Cai
- Division of Nephrology and Hypertension, Department of Medicine, Center for Translational Metabolism and Health, Institute for Public Health and Medicine, Northwestern University Feinberg School of Medicine, Chicago, Illinois, USA
| | | | - Norma Ofsthun
- Fresenius Medical Care North America, Waltham, Massachusetts, USA
| | - Zhiying You
- Division of Renal Diseases and Hypertension, University of Colorado Denver Anschutz Medical Campus, Aurora, Colorado, USA
| | - Harmut H Malluche
- Division of Nephrology, Bone and Mineral Metabolism, Department of Medicine, University of Kentucky Chandler Medical Center, Lexington, Kentucky, USA
| | | | - Diana George
- Division of Renal Diseases and Hypertension, University of Colorado Denver Anschutz Medical Campus, Aurora, Colorado, USA
| | - Vicente Torres
- Division of Nephrology and Hypertension, Mayo Clinic, Rochester, Minnesota, USA
| | - Arlene Chapman
- Section of Nephrology, University of Chicago, Chicago, Illinois, USA
| | - Theodore I Steinman
- Department of Medicine and Renal Division, Beth Israel Deaconess Medical Center, Boston, Massachusetts, USA
| | - Myles Wolf
- Division of Nephrology, Department of Medicine, Duke Clinical Research Institute, Duke University School of Medicine, Durham, North Carolina, USA
| | - Michel Chonchol
- Division of Renal Diseases and Hypertension, University of Colorado Denver Anschutz Medical Campus, Aurora, Colorado, USA.
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5
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Bone biomarkers in de novo renal transplant recipients. Clin Chim Acta 2019; 501:179-185. [PMID: 31734147 DOI: 10.1016/j.cca.2019.10.035] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2019] [Accepted: 10/24/2019] [Indexed: 12/30/2022]
Abstract
Successful kidney transplantation (partly) corrects the physiologic and metabolic abnormalities driving chronic kidney disease - mineral and bone disorders. At the same time, renal transplant recipients are exposed to immunosuppressive agents that may affect bone metabolism. Bone biomarkers have been suggested as surrogates of or adjuncts to bone biopsy and imaging techniques to assess bone health and to classify risk of bone loss and fractures. Bone biomarkers may be classified as circulating factors that affect bone metabolism (commonly referred to as bone metabolism markers) or that reflect bone cell number and/or activity (commonly referred to as bone turnover markers). A growing body of evidence shows that successful renal transplantation has a major impact on both bone metabolism and bone turnover. Analytical issues, including the cross-reactivity with fragments, complicate the interpretation of bone biomarkers, especially in the setting of a rapid changing kidney function, as is the case after successful renal transplantation. Overall, bone turnover seems to decline following renal transplantation, but inter-individual variability is substantial. Preliminary evidence indicates that bone biomarkers may be useful in guiding mineral and bone therapy in renal transplant recipients.
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Laster M, Pereira RC, Salusky IB. Unraveling the osteocyte in CKD-MBD post-renal transplantation. Kidney Int 2019; 96:1059-1061. [PMID: 31648693 DOI: 10.1016/j.kint.2019.07.021] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2019] [Revised: 07/18/2019] [Accepted: 07/26/2019] [Indexed: 12/01/2022]
Abstract
Changes in indices of mineral metabolism, bone protein expression, and bone turnover were assessed between pre- and post-renal transplant bone biopsies obtained 12 months apart. Circulating sclerostin and fibroblast growth factor 23 (FGF-23) levels decreased, and a low bone turnover state was highly prevalent on follow-up. In contrast, bone sclerostin expression increased, whereas FGF-23 bone expression was unchanged/decreased. These findings underscore the limitations of circulating biomarkers and the critical role of bone biopsy to understand osteocyte biology in chronic kidney disease-mineral bone disorder.
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Affiliation(s)
- Marciana Laster
- Department of Pediatrics, David Geffen School of Medicine at UCLA, Los Angeles, California, USA
| | - Renata C Pereira
- Department of Pediatrics, David Geffen School of Medicine at UCLA, Los Angeles, California, USA
| | - Isidro B Salusky
- Department of Pediatrics, David Geffen School of Medicine at UCLA, Los Angeles, California, USA.
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Lerch C, Shroff R, Wan M, Rees L, Aitkenhead H, Kaplan Bulut I, Thurn D, Karabay Bayazit A, Niemirska A, Canpolat N, Duzova A, Azukaitis K, Yilmaz E, Yalcinkaya F, Harambat J, Kiyak A, Alpay H, Habbig S, Zaloszyc A, Soylemezoglu O, Candan C, Rosales A, Melk A, Querfeld U, Leifheit-Nestler M, Sander A, Schaefer F, Haffner D. Effects of nutritional vitamin D supplementation on markers of bone and mineral metabolism in children with chronic kidney disease. Nephrol Dial Transplant 2019; 33:2208-2217. [PMID: 29481636 DOI: 10.1093/ndt/gfy012] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2017] [Accepted: 12/14/2017] [Indexed: 12/13/2022] Open
Abstract
Background We investigated the effects of nutritional vitamin D supplementation on markers of bone and mineral metabolism, i.e. serum levels of fibroblast growth factor 23 (FGF23), Klotho, bone alkaline phosphatase (BAP) and sclerostin, in two cohorts with chronic kidney disease (CKD). Methods In all, 80 vitamin D-deficient children were selected: 40 with mild to moderate CKD from the ERGO study, a randomized trial of ergocalciferol supplementation [estimated glomerular filtration rate (eGFR) 55 mL/min/1.73 m2], and 40 with advanced CKD from the observational Cardiovascular Comorbidity in Children with Chronic Kidney Disease (4C) study (eGFR 24 mL/min/1.73 m2). In each study, vitamin D supplementation was started in 20 children and 20 matched children not receiving vitamin D served as controls. Measures were taken at baseline and after a median period of 8 months. Age- and gender-related standard deviation scores (SDSs) were calculated. Results Before vitamin D supplementation, children in the ERGO study had normal FGF23 (median 0.31 SDS) and BAP (-0.10 SDS) but decreased Klotho and sclerostin (-0.77 and -1.04 SDS, respectively), whereas 4C patients had increased FGF23 (3.87 SDS), BAP (0.78 SDS) and sclerostin (0.76 SDS) but normal Klotho (-0.27 SDS) levels. Vitamin D supplementation further increased FGF23 in 4C but not in ERGO patients. Serum Klotho and sclerostin normalized with vitamin D supplementation in ERGO but remained unchanged in 4C patients. BAP levels were unchanged in all patients. In the total cohort, significant effects of vitamin D supplementation were noted for Klotho at eGFR 40-70 mL/min/1.73 m2. Conclusions Vitamin D supplementation normalized Klotho and sclerostin in children with mild to moderate CKD but further increased FGF23 in advanced CKD.
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Affiliation(s)
- Christian Lerch
- Department of Pediatric Kidney, Liver and Metabolic Diseases, Hannover Medical School Children's Hospital, Hannover, Germany
| | - Rukshana Shroff
- Renal Unit, Great Ormond Street Hospital for Children, London, UK
| | - Mandy Wan
- Renal Unit, Great Ormond Street Hospital for Children, London, UK
| | - Lesley Rees
- Renal Unit, Great Ormond Street Hospital for Children, London, UK
| | - Helen Aitkenhead
- Department of Chemical Pathology, Great Ormond Street Hospital for Children, London, UK
| | - Ipek Kaplan Bulut
- Department of Pediatric Nephrology, Ege University, Bornova, Izmir, Turkey
| | - Daniela Thurn
- Department of Pediatric Kidney, Liver and Metabolic Diseases, Hannover Medical School Children's Hospital, Hannover, Germany
| | - Aysun Karabay Bayazit
- Department of Pediatric Nephrology, Faculty of Medicine, Cukurova University, Adana, Turkey
| | - Anna Niemirska
- Department of Nephrology, Kidney Transplantation and Arterial Hypertension, Children's Memorial Health Institute, Warsaw, Poland
| | - Nur Canpolat
- Department of Pediatrics, Istanbul University Cerrahpasa Faculty of Medicine, Istanbul, Turkey
| | - Ali Duzova
- Division of Pediatric Nephrology, Hacettepe University, Faculty of Medicine, Ankara, Turkey
| | - Karolis Azukaitis
- Clinic of Pediatrics, Faculty of Medicine, Vilnius University, Vilnius, Lithuania
| | - Ebru Yilmaz
- Department of Pediatric Nephrology, Sanliurfa Children's Hospital, Sanliurfa, Turkey
| | - Fatos Yalcinkaya
- Department of Pediatric Nephrology, School of Medicine, Ankara University, Ankara, Turkey
| | - Jerome Harambat
- Department of Pediatrics, Bordeaux University Hospital, Bordeaux, France
| | - Aysel Kiyak
- Department of Pediatric Nephrology, Yenimahalle Egitim ve Arastirma Hastanesi Bakirkoy, Istanbul, Turkey
| | - Harika Alpay
- Department of Pediatric Nephrology, Marmara University School of Medicine, Istanbul, Turkey
| | - Sandra Habbig
- Division of Pediatric Nephrology, University Children's and Adolescent's Hospital, Cologne, Germany
| | - Ariane Zaloszyc
- Pole Médico-Chirurgical de Pédiatrie, Service de Pédiatrie I, Hôpitaux Universitaires de Strasbourg, Strasbourg, France
| | - Oguz Soylemezoglu
- Department of Pediatric Nephrology, Gazi University Hospital, Ankara, Turkey
| | - Cengiz Candan
- Department of Pediatric Nephrology, Göztepe Egitim ve Arastirma Hastanesi, Cocuk Klinigi, Göztepe, Istanbul, Turkey
| | - Alejandra Rosales
- Department of Pediatrics, Innsbruck Medical University, Innsbruck, Austria
| | - Anette Melk
- Department of Pediatric Kidney, Liver and Metabolic Diseases, Hannover Medical School Children's Hospital, Hannover, Germany
| | - Uwe Querfeld
- Clinic of Pediatric Nephrology, Charite Children's Hospital, Berlin, Germany
| | - Maren Leifheit-Nestler
- Department of Pediatric Kidney, Liver and Metabolic Diseases, Hannover Medical School Children's Hospital, Hannover, Germany
| | - Anja Sander
- Institute of Medical Biometry and Informatics, University Heidelberg, Heidelberg, Germany
| | | | - Dieter Haffner
- Department of Pediatric Kidney, Liver and Metabolic Diseases, Hannover Medical School Children's Hospital, Hannover, Germany
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Comparison of serum levels with bone content and gene expression indicate a contradictory effect of kidney transplantation on sclerostin. Kidney Int 2019; 96:1100-1104. [PMID: 31526513 DOI: 10.1016/j.kint.2019.06.007] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2019] [Revised: 05/31/2019] [Accepted: 06/07/2019] [Indexed: 01/28/2023]
Abstract
In an attempt to clarify the mechanisms of post-transplant bone disease we investigated the bone content and gene expression of several bone-related proteins. After a successful kidney transplant, the content of sclerostin in bone biopsies was found to be increased as measured by immunohistochemistry, multiplex assay, and gene expression despite a concomitant decrease of sclerostin in the serum. The phosphorylation of beta-catenin was increased, confirming Wnt pathway inhibition, an effect accompanied by an increase of the receptor activator of nuclear factor kappa-Β ligand (RANKL) and a decrease of osteoprotegerin protein levels in both serum and bone. Thus, changes in circulating biomarkers after kidney transplantation cannot be easily extrapolated to concomitant changes occurring in the bone. Hence, overall treatment decisions post kidney transplant should not be based on serum biochemistry alone.
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9
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Boltenstål H, Qureshi AR, Behets GJ, Lindholm B, Stenvinkel P, D'Haese PC, Haarhaus M. Association of Serum Sclerostin with Bone Sclerostin in Chronic Kidney Disease is Lost in Glucocorticoid Treated Patients. Calcif Tissue Int 2019; 104:214-223. [PMID: 30406279 DOI: 10.1007/s00223-018-0491-4] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/25/2018] [Accepted: 10/27/2018] [Indexed: 01/08/2023]
Abstract
The osteocytic protein sclerostin inhibits bone turnover. Serum sclerostin rises early in chronic kidney disease (CKD), but if this reflects osteocyte sclerostin production is unclear, since sclerostin is also expressed in extra-skeletal tissue. Glucocorticoid treatment impacts on serum sclerostin, but the effect on the association between serum and bone sclerostin is unknown. We sought to determine whether serum sclerostin reflects bone sclerostin in different CKD stages and how this association is influenced by glucocorticoid treatment. In a cross-sectional analysis, we investigated serum sclerostin, bone sclerostin by immunohistochemistry, and bone histomorphometry in iliac crest bone biopsies from 43 patients with CKD 3-5D, including 14 dialysis patients and 22 transplanted patients (18 kidney, 4 other). Thirty-one patients were on glucocorticoid treatment at time of biopsy. Patients with low bone turnover (bone formation rate < 97 µm²/mm²/day; N = 13) had higher median serum sclerostin levels (224.7 vs. 141.7 pg/ml; P = 0.004) and higher bone sclerostin, expressed as sclerostin positive osteocytes per bone area (12.1 vs. 5.0 Scl+ osteocytes/B.Ar; P = 0.008), than patients with non-low bone turnover (N = 28). In linear regression analyses, correcting for age, gender, dialysis status and PTH, serum sclerostin was only associated with bone sclerostin in patients not treated with glucocorticoids (r2 = 0.6, P = 0.018). For the first time, we describe that female CKD patients have higher median bone sclerostin than males (11.7 vs. 5.7 Scl+ osteocytes/B.Ar, P = 0.046), despite similar serum sclerostin levels and bone histo-morphometric parameters. We conclude that glucocorticoid treatment appears to disrupt the association of serum sclerostin with bone sclerostin in CKD.
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Affiliation(s)
- Henrik Boltenstål
- Division of Renal Medicine and Baxter Novum, Karolinska University Hospital at Huddinge, Karolinska Institutet, 14186, Stockholm, Sweden
| | - Abdul Rashid Qureshi
- Division of Renal Medicine and Baxter Novum, Karolinska University Hospital at Huddinge, Karolinska Institutet, 14186, Stockholm, Sweden
| | - Geert J Behets
- Laboratory of Pathophysiology, Department of Biomedical Sciences, University of Antwerp, Antwerp, Belgium
| | - Bengt Lindholm
- Division of Renal Medicine and Baxter Novum, Karolinska University Hospital at Huddinge, Karolinska Institutet, 14186, Stockholm, Sweden
| | - Peter Stenvinkel
- Division of Renal Medicine and Baxter Novum, Karolinska University Hospital at Huddinge, Karolinska Institutet, 14186, Stockholm, Sweden
| | - Patrick C D'Haese
- Laboratory of Pathophysiology, Department of Biomedical Sciences, University of Antwerp, Antwerp, Belgium
| | - Mathias Haarhaus
- Division of Renal Medicine and Baxter Novum, Karolinska University Hospital at Huddinge, Karolinska Institutet, 14186, Stockholm, Sweden.
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10
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Hernandez MJ, dos Reis LM, Marques ID, Araujo MJ, Truyts CAM, Oliveira IB, Barreto FC, David-Neto E, Custodio MR, Moyses RM, Bellorin-Font E, Jorgetti V. The effect of vitamin D and zoledronic acid in bone marrow adiposity in kidney transplant patients: A post hoc analysis. PLoS One 2018; 13:e0197994. [PMID: 29799857 PMCID: PMC5969759 DOI: 10.1371/journal.pone.0197994] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2017] [Accepted: 05/10/2018] [Indexed: 11/19/2022] Open
Abstract
PURPOSE Osteoblasts and adipocytes are derived from mesenchymal stem cells. An imbalance in the differentiation of these lineages could affect the preservation of bone integrity. Several studies have suggested the importance of this imbalance in the pathogenesis of osteoporosis after kidney transplant (KT), but the role of bone marrow adiposity in this process is not well known, and if the treatment with the anti-absorptive (zoledronic acid-ZA) drugs could attenuate bone loss. Thus, our objective was compare bone marrow adiposity, osteoblasts and osteocytes before and after KT, verify an association between bone remodeling process (Turnover, Volume, and Mineralization-TMV classification), the osteocyte sclerostin expression to evaluate if there is a role of Wnt pathway, as well as the effect of ZA on these cells. METHODS We studied 29 new living-donor KT patients. One group received ZA at the time of KT plus cholecalciferol for twelve months, and the other group received only cholecalciferol. Bone biopsies were performed at baseline and after 12 months of treatment. Histomorphometric evaluation was performed in bone and bone marrow adipocytes. Sclerostin (Scl) expression in osteocytes was evaluated by immunohistochemistry. RESULTS Some bone marrow adiposity parameters were increased before KT. After KT, some of them remained increased and they worsened with the use of ZA. In the baseline, lower bone Volume and Turnover, were associated with increased bone marrow adiposity parameters (some of them). After KT, both groups showed the same associations. Osteocyte Scl expression after KT decreased with the use of ZA. We observed also an inverse association between bone adiposity parameters and lower osteocyte sclerostin expression 12 months after KT. CONCLUSION In conclusion, the present study suggests that KT fails to normalize bone marrow adiposity, and it even gets worse with the use of ZA. Moreover, bone marrow adiposity is inversely associated with bone Volume and Turnover, which seems to be accentuated by the antiresorptive therapy.
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Affiliation(s)
- Mariel J. Hernandez
- LIM 16 – Laboratorio de Fisiopatologia Renal, Hospital das Clinicas HCFMUSP, Faculdade de Medicina, Universidade de Sao Paulo, Sao Paulo, Sao Paulo, Brasil
- Servicio de Nefrología y Trasplante Renal, Hospital Universitario de Caracas, Universidad Central de Venezuela, Caracas, Venezuela
| | - Luciene M. dos Reis
- LIM 16 – Laboratorio de Fisiopatologia Renal, Hospital das Clinicas HCFMUSP, Faculdade de Medicina, Universidade de Sao Paulo, Sao Paulo, Sao Paulo, Brasil
| | - Igor D. Marques
- LIM 16 – Laboratorio de Fisiopatologia Renal, Hospital das Clinicas HCFMUSP, Faculdade de Medicina, Universidade de Sao Paulo, Sao Paulo, Sao Paulo, Brasil
| | - Maria J. Araujo
- LIM 16 – Laboratorio de Fisiopatologia Renal, Hospital das Clinicas HCFMUSP, Faculdade de Medicina, Universidade de Sao Paulo, Sao Paulo, Sao Paulo, Brasil
- Divisao de Urologia, Hospital das Clinicas, HCFMUSP, Faculdade de Medicina, Universidade de Sao Paulo, Sao Paulo, Sao Paulo, Brasil
| | - Cesar A. M. Truyts
- LIM 16 – Laboratorio de Fisiopatologia Renal, Hospital das Clinicas HCFMUSP, Faculdade de Medicina, Universidade de Sao Paulo, Sao Paulo, Sao Paulo, Brasil
| | - Ivone B. Oliveira
- LIM 16 – Laboratorio de Fisiopatologia Renal, Hospital das Clinicas HCFMUSP, Faculdade de Medicina, Universidade de Sao Paulo, Sao Paulo, Sao Paulo, Brasil
| | - Fellype C. Barreto
- Divisao de Nefrologia, Universidade Federal do Parana, Curitiba, Parana, Brasil
| | - Elias David-Neto
- Divisao de Urologia, Hospital das Clinicas, HCFMUSP, Faculdade de Medicina, Universidade de Sao Paulo, Sao Paulo, Sao Paulo, Brasil
| | - Melani R. Custodio
- LIM 16 – Laboratorio de Fisiopatologia Renal, Hospital das Clinicas HCFMUSP, Faculdade de Medicina, Universidade de Sao Paulo, Sao Paulo, Sao Paulo, Brasil
| | - Rosa M. Moyses
- LIM 16 – Laboratorio de Fisiopatologia Renal, Hospital das Clinicas HCFMUSP, Faculdade de Medicina, Universidade de Sao Paulo, Sao Paulo, Sao Paulo, Brasil
- Programa de Pos-Graduaçao em Medicina, Universidade Nove de Julho (UNINOVE), Sao Paulo, Sao Paulo, Brasil
| | - Ezequiel Bellorin-Font
- Servicio de Nefrología y Trasplante Renal, Hospital Universitario de Caracas, Universidad Central de Venezuela, Caracas, Venezuela
| | - Vanda Jorgetti
- LIM 16 – Laboratorio de Fisiopatologia Renal, Hospital das Clinicas HCFMUSP, Faculdade de Medicina, Universidade de Sao Paulo, Sao Paulo, Sao Paulo, Brasil
- Hospital Samaritano Americas Serviços Medicos, Sao Paulo, Sao Paulo, Brasil
- * E-mail:
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11
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De Rechter S, Bacchetta J, Godefroid N, Dubourg L, Cochat P, Maquet J, Raes A, De Schepper J, Vermeersch P, Van Dyck M, Levtchenko E, D'Haese P, Evenepoel P, Mekahli D. Evidence for Bone and Mineral Metabolism Alterations in Children With Autosomal Dominant Polycystic Kidney Disease. J Clin Endocrinol Metab 2017; 102:4210-4217. [PMID: 29092060 DOI: 10.1210/jc.2017-01157] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/19/2017] [Accepted: 09/13/2017] [Indexed: 01/08/2023]
Abstract
CONTEXT Autosomal dominant polycystic kidney disease (ADPKD) is the most common hereditary kidney disease. Hypophosphatemia was demonstrated in adult patients with preserved renal function, together with high fibroblast growth factor 23 (FGF23) and low soluble Klotho levels. The latter explained the relative FGF23 hyporesponsiveness in this cohort. OBJECTIVE Evaluating phosphate and bone mineral metabolism in children with ADPKD compared with what is known in adult ADPKD patients. DESIGN Observational cross-sectional study. SETTING Multicenter study via ambulatory care in tertiary centers. PARTICIPANTS Ninety-two children with ADPKD (52 males; mean ± standard deviation age, 10.2 ± 5.0 years) and 22 healthy controls (HCs, 10 males; mean ± standard deviation age, 10.3 ± 4.1 years). MAIN OUTCOME MEASURES The predictor was early ADPKD stage. Bone mineral metabolism and renal phosphate handling were the main outcome measures. Performed measurements were serum phosphate, tubular maximum phosphorus reabsorption per glomerular filtration rate, FGF23, soluble Klotho, sclerostin, and bone alkaline phosphatase. RESULTS ADPKD children had significantly lower serum phosphate levels compared with HC. Low tubular maximum phosphorus reabsorption per glomerular filtration rate was observed in 24% of patients, although not significantly different from HC. Serum FGF23 and soluble Klotho levels were comparable between patients and HC. In addition, we showed decreased bone alkaline phosphatase levels in ADPKD children, suggesting suppressed bone formation. CONCLUSIONS This report demonstrates hypophosphatemia and suppressed bone formation in a pediatric ADPKD cohort, with preserved renal function, compared with HC. Although FGF23 levels were not different from controls, they should be considered inappropriate, given the concomitant hypophosphatemia. Further studies are required to elucidate underlying pathophysiology and potential clinical consequences.
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Affiliation(s)
- Stéphanie De Rechter
- Department of Pediatric Nephrology, University Hospitals Leuven, Leuven 3000, Belgium
- Laboratory of Pediatric Nephrology, KU Leuven, Leuven, Leuven 3000, Belgium
| | - Justine Bacchetta
- Centre de Référence des Maladies Rénales Rares, Hôpital Femme Mère Enfant, Hospices Civils de Lyon, 69500 Bron, France
| | - Nathalie Godefroid
- Department of Pediatric Nephrology, Cliniques Universitaires Saint-Luc, Brussels 1200, Belgium
| | - Laurence Dubourg
- Centre de Référence des Maladies Rénales Rares, Hôpital Femme Mère Enfant, Hospices Civils de Lyon, 69500 Bron, France
| | - Pierre Cochat
- Centre de Référence des Maladies Rénales Rares, Hôpital Femme Mère Enfant, Hospices Civils de Lyon, 69500 Bron, France
| | - Julie Maquet
- Department of Pediatric Nephrology, CHC, Liège 4420, Belgium
| | - Ann Raes
- Department of Pediatric Nephrology, University Hospitals Ghent, Ghent 9000, Belgium
| | - Jean De Schepper
- Department of Pediatric Endocrinology, Department of Pediatrics, Brussels University Hospital, Brussels 1090, Belgium
| | - Pieter Vermeersch
- Laboratory Medicine, University Hospitals Leuven 3000, Leuven, Belgium
| | - Maria Van Dyck
- Department of Pediatric Nephrology, University Hospitals Leuven, Leuven 3000, Belgium
- Laboratory of Pediatric Nephrology, KU Leuven, Leuven, Leuven 3000, Belgium
| | - Elena Levtchenko
- Department of Pediatric Nephrology, University Hospitals Leuven, Leuven 3000, Belgium
- Laboratory of Pediatric Nephrology, KU Leuven, Leuven, Leuven 3000, Belgium
| | - Patrick D'Haese
- Laboratory of Pathophysiology, University of Antwerp, Antwerp 2000, Belgium
| | - Pieter Evenepoel
- Department of Internal Medicine, Division of Nephrology, University Hospitals Leuven, Leuven 3000, Belgium
| | - Djalila Mekahli
- Department of Pediatric Nephrology, University Hospitals Leuven, Leuven 3000, Belgium
- Laboratory of Pediatric Nephrology, KU Leuven, Leuven, Leuven 3000, Belgium
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12
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Tartaglione L, Pasquali M, Rotondi S, Muci ML, Leonangeli C, Farcomeni A, Fassino V, Mazzaferro S. Interactions of sclerostin with FGF23, soluble klotho and vitamin D in renal transplantation. PLoS One 2017; 12:e0178637. [PMID: 28558021 PMCID: PMC5448809 DOI: 10.1371/journal.pone.0178637] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2016] [Accepted: 05/16/2017] [Indexed: 01/05/2023] Open
Abstract
Relationships of Sclerostin, a bone anti-anabolic protein, with biomarkers of mineral bone disorders in chronic kidney disease are still unsettled, in particular in kidney transplant (KTR). In 80 KTR patients (31F/49M, 54.7±10.3 years) we studied the relationships of serum Sclerostin with eGFR, Calcium, Phosphate, Alkaline Phosphatase (AP), intact Parathyroid hormone (iPTH), soluble alpha-Klotho (sKlotho), intact Fibroblast Growth Factor 23 (iFGF23), 25-hydroxyvitamin D(25D) and 1,25-dihydroxyvitamin D (1,25D). Thirty healthy subjects (35.0±12.4 years, eGFR 109.1±14.1 ml /min/1,73m2) served as control for Sclerostin, iFGF23 and sKlotho. With a median eGFR of 46.3 mL/min/1.73m2 (IQR, 36.2–58.3) our KTR had median Sclerostin levels of 23.7 pmol/L (IQR: 20.8–32.8), not different from controls (26.6 pmol/L, IQR: 22.0–32.2; p = n.s). Sclerostin correlated negatively with AP (r = -.251; p = 0.023) and positively with iFGF23 (r = .227; p = 0.017) and 25D (r = .214; p = 0.025). Age-adjusted multiple regression analysis identified AP and 1,25D as negative and 25D and sKlotho as positive best predictors of Sclerostin. No correlation was evident with eGFR. The negative correlation with AP confirms the direct anti-anabolic role of Sclerostin. The associations either negative or positive with iFGF23, sKlotho, and vitamin D metabolites suggest also a modulatory role in mineral homeostasis. In particular, the associations with iFGF23 (positive) and 1,25D (negative) underline the relevant inhibitory action of Sclerostin on vitamin D activation. In conclusion, Sclerostin levels in KTR are normal and influenced more by bone turnover than by eGFR. Its involvement with other hormones of mineral homeostasis (FGF23/Klotho and Vitamin D) is part of the sophisticated cross-talk between bone and the kidney.
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Affiliation(s)
- Lida Tartaglione
- Department of Cardiovascular, Respiratory, Nephrologic, Anesthesiologic and Geriatric Sciences, Sapienza University of Rome, Italy
| | - Marzia Pasquali
- Department of Nephrology and Dialysis, University Hospital Company, Policlinico Umberto I, Rome, Italy
| | - Silverio Rotondi
- Department of Cardiovascular, Respiratory, Nephrologic, Anesthesiologic and Geriatric Sciences, Sapienza University of Rome, Italy
| | - Maria Luisa Muci
- Department of Cardiovascular, Respiratory, Nephrologic, Anesthesiologic and Geriatric Sciences, Sapienza University of Rome, Italy
| | - Cristiana Leonangeli
- Department of Cardiovascular, Respiratory, Nephrologic, Anesthesiologic and Geriatric Sciences, Sapienza University of Rome, Italy
| | - Alessio Farcomeni
- Department of Public Health and Infectious Diseases, Sapienza University of Rome, Italy
| | - Valeria Fassino
- Department of Internal Medicine and medical Specialties, University Hospital Company, Policlinico Umberto I, Rome, Italy
| | - Sandro Mazzaferro
- Department of Cardiovascular, Respiratory, Nephrologic, Anesthesiologic and Geriatric Sciences, Sapienza University of Rome, Italy
- * E-mail:
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13
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Fratzl-Zelman N, Valta H, Pereira RC, Misof BM, Roschger P, Jalanko H, Wesseling-Perry K, Klaushofer K, Mäkitie O. Abnormally High and Heterogeneous Bone Matrix Mineralization After Childhood Solid Organ Transplantation: A Complex Pathology of Low Bone Turnover and Local Defects in Mineralization. J Bone Miner Res 2017; 32:1116-1125. [PMID: 28214296 DOI: 10.1002/jbmr.3087] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/22/2016] [Revised: 01/18/2017] [Accepted: 01/20/2017] [Indexed: 01/20/2023]
Abstract
Chronic renal, liver, and heart failure in children associates with multiple skeletal complications. Increased fracture incidence often persists after transplantation and could be related to alterations in bone material properties. In the present cohort study we evaluated bone mineralization density distribution (BMDD) by quantitative backscattered electron imaging (qBEI) in 23 pediatric solid organ allograft recipients with suspected osteoporosis. We measured BMDD in the entire cross-sectional area of transiliac bone biopsies obtained from kidney (n = 9), liver (n = 9), and heart (n = 5) transplant recipients (aged 7.6 to 19.7 years; 6.0 ± 5.6 years posttransplantation, patients with a history of clinical fractures: n = 14). The BMDD findings were compared with age-appropriate references and with a previously presented cohort of children with chronic kidney disease on dialysis (CKD5D, n = 18). Furthermore, we related the BMDD parameters with patients' clinical and bone histomorphometric outcomes. Compared to healthy children, qBEI results for cancellous and cortical bone in transplant recipients revealed an increase in the most frequently occurring calcium concentration (+2.9%, p = 0.001; +3.5%, p = 0.014), in the portion of fully mineralized bone (fivefold; 10-fold, both p < 0.0001) and in heterogeneity of mineralization (+26,5% and +27.8%, both p < 0.0001), respectively. Moreover, the BMDD parameters were nonsignificantly distinct from CKD5D cohort except that the heterogeneity in mineralization was higher posttransplantation. There was a strong inverse correlation between the average calcium content of the bone matrix and patients' biochemical ALP levels, histomorphometric indices of bone formation and resorption. The abnormally high bone matrix mineralization in transplant recipients, consistent with serum and histomorphometric outcomes, suggests a history of low bone turnover with accumulation of fully mineralized bone packets. Additionally, the increased heterogeneity of mineralization suggests local alterations in mineralization kinetics, which may be linked to dysfunctional osteocytes that were recently shown to accumulate within the bone matrix during organ failure and concomitant glucocorticoid and immunosuppressive medication. © 2017 American Society for Bone and Mineral Research.
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Affiliation(s)
- Nadja Fratzl-Zelman
- Ludwig Boltzmann Institute of Osteology at Hanusch Hospital of WGKK and AUVA Trauma Centre, Meidling, 1st Med. Dept. Hanusch Hospital, Vienna, Austria
| | - Helena Valta
- Children's Hospital, Helsinki University Central Hospital and University of Helsinki, Helsinki, Finland
| | - Renata C Pereira
- Department of Pediatrics, David Geffen School of Medicine at UCLA, Los Angeles, CA, USA
| | - Barbara M Misof
- Ludwig Boltzmann Institute of Osteology at Hanusch Hospital of WGKK and AUVA Trauma Centre, Meidling, 1st Med. Dept. Hanusch Hospital, Vienna, Austria
| | - Paul Roschger
- Ludwig Boltzmann Institute of Osteology at Hanusch Hospital of WGKK and AUVA Trauma Centre, Meidling, 1st Med. Dept. Hanusch Hospital, Vienna, Austria
| | - Hannu Jalanko
- Children's Hospital, Helsinki University Central Hospital and University of Helsinki, Helsinki, Finland
| | | | - Klaus Klaushofer
- Ludwig Boltzmann Institute of Osteology at Hanusch Hospital of WGKK and AUVA Trauma Centre, Meidling, 1st Med. Dept. Hanusch Hospital, Vienna, Austria
| | - Outi Mäkitie
- Children's Hospital, Helsinki University Central Hospital and University of Helsinki, Helsinki, Finland.,Folkhälsan Research Center, Helsinki, Finland.,Department of Molecular Medicine and Surgery, Karolinska Institute, Stockholm, Sweden.,Department of Clinical Genetics, Karolinska University Hospital, Stockholm, Sweden
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14
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Intramembranous bone regeneration and implant placement using mechanical femoral marrow ablation: rodent models. BONEKEY REPORTS 2016; 5:837. [PMID: 27648259 DOI: 10.1038/bonekey.2016.61] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/10/2016] [Accepted: 07/19/2016] [Indexed: 12/16/2022]
Abstract
In this paper, we provide a detailed protocol for a model of long bone mechanical marrow ablation in the rodent, including surgical procedure, anesthesia, and pre- and post-operative care. In addition, frequently used experimental end points are briefly discussed. This model was developed to study intramembranous bone regeneration following surgical disruption of the marrow contents of long bones. In this model, the timing of the appearance of bone formation and remodeling is well-characterized and therefore the model is well-suited to evaluate the in vivo effects of various agents which influence these processes. When biomaterials such as tissue engineering scaffolds or metal implants are placed in the medullary cavity after marrow ablation, end points relevant to tissue engineering and implant fixation can also be analyzed. By sharing a detailed protocol, we hope to improve inter-laboratory reproducibility.
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