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Brylka LJ, Alimy AR, Tschaffon-Müller MEA, Jiang S, Ballhause TM, Baranowsky A, von Kroge S, Delsmann J, Pawlus E, Eghbalian K, Püschel K, Schoppa A, Haffner-Luntzer M, Beech DJ, Beil FT, Amling M, Keller J, Ignatius A, Yorgan TA, Rolvien T, Schinke T. Piezo1 expression in chondrocytes controls endochondral ossification and osteoarthritis development. Bone Res 2024; 12:12. [PMID: 38395992 PMCID: PMC10891122 DOI: 10.1038/s41413-024-00315-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2023] [Revised: 12/18/2023] [Accepted: 01/01/2024] [Indexed: 02/25/2024] Open
Abstract
Piezo proteins are mechanically activated ion channels, which are required for mechanosensing functions in a variety of cell types. While we and others have previously demonstrated that the expression of Piezo1 in osteoblast lineage cells is essential for bone-anabolic processes, there was only suggestive evidence indicating a role of Piezo1 and/or Piezo2 in cartilage. Here we addressed the question if and how chondrocyte expression of the mechanosensitive proteins Piezo1 or Piezo2 controls physiological endochondral ossification and pathological osteoarthritis (OA) development. Mice with chondrocyte-specific inactivation of Piezo1 (Piezo1Col2a1Cre), but not of Piezo2, developed a near absence of trabecular bone below the chondrogenic growth plate postnatally. Moreover, all Piezo1Col2a1Cre animals displayed multiple fractures of rib bones at 7 days of age, which were located close to the growth plates. While skeletal growth was only mildly affected in these mice, OA pathologies were markedly less pronounced compared to littermate controls at 60 weeks of age. Likewise, when OA was induced by anterior cruciate ligament transection, only the chondrocyte inactivation of Piezo1, not of Piezo2, resulted in attenuated articular cartilage degeneration. Importantly, osteophyte formation and maturation were also reduced in Piezo1Col2a1Cre mice. We further observed increased Piezo1 protein abundance in cartilaginous zones of human osteophytes. Finally, we identified Ptgs2 and Ccn2 as potentially relevant Piezo1 downstream genes in chondrocytes. Collectively, our data do not only demonstrate that Piezo1 is a critical regulator of physiological and pathological endochondral ossification processes, but also suggest that Piezo1 antagonists may be established as a novel approach to limit osteophyte formation in OA.
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Affiliation(s)
- Laura J Brylka
- Department of Osteology and Biomechanics, University Medical Center Hamburg-Eppendorf, 20246, Hamburg, Germany
| | - Assil-Ramin Alimy
- Department of Trauma and Orthopedic Surgery, University Medical Center Hamburg-Eppendorf, 20246, Hamburg, Germany
| | - Miriam E A Tschaffon-Müller
- Institute of Orthopedic Research and Biomechanics, University Medical Center Ulm, Baden-Württemberg, 89081, Ulm, Germany
| | - Shan Jiang
- Department of Trauma and Orthopedic Surgery, University Medical Center Hamburg-Eppendorf, 20246, Hamburg, Germany
| | - Tobias Malte Ballhause
- Department of Trauma and Orthopedic Surgery, University Medical Center Hamburg-Eppendorf, 20246, Hamburg, Germany
| | - Anke Baranowsky
- Department of Trauma and Orthopedic Surgery, University Medical Center Hamburg-Eppendorf, 20246, Hamburg, Germany
| | - Simon von Kroge
- Department of Osteology and Biomechanics, University Medical Center Hamburg-Eppendorf, 20246, Hamburg, Germany
- Department of Trauma and Orthopedic Surgery, University Medical Center Hamburg-Eppendorf, 20246, Hamburg, Germany
| | - Julian Delsmann
- Department of Trauma and Orthopedic Surgery, University Medical Center Hamburg-Eppendorf, 20246, Hamburg, Germany
| | - Eva Pawlus
- Department of Osteology and Biomechanics, University Medical Center Hamburg-Eppendorf, 20246, Hamburg, Germany
| | - Kian Eghbalian
- Department of Osteology and Biomechanics, University Medical Center Hamburg-Eppendorf, 20246, Hamburg, Germany
| | - Klaus Püschel
- Department Legal Medicine, University Medical Center Hamburg-Eppendorf, 20246, Hamburg, Germany
| | - Astrid Schoppa
- Institute of Orthopedic Research and Biomechanics, University Medical Center Ulm, Baden-Württemberg, 89081, Ulm, Germany
| | - Melanie Haffner-Luntzer
- Institute of Orthopedic Research and Biomechanics, University Medical Center Ulm, Baden-Württemberg, 89081, Ulm, Germany
| | - David J Beech
- Leeds Institute of Cardiovascular and Metabolic Medicine, School of Medicine, University of Leeds, LS2 9JT, Leeds, UK
| | - Frank Timo Beil
- Department of Trauma and Orthopedic Surgery, University Medical Center Hamburg-Eppendorf, 20246, Hamburg, Germany
| | - Michael Amling
- Department of Osteology and Biomechanics, University Medical Center Hamburg-Eppendorf, 20246, Hamburg, Germany
| | - Johannes Keller
- Department of Trauma and Orthopedic Surgery, University Medical Center Hamburg-Eppendorf, 20246, Hamburg, Germany
| | - Anita Ignatius
- Institute of Orthopedic Research and Biomechanics, University Medical Center Ulm, Baden-Württemberg, 89081, Ulm, Germany
| | - Timur A Yorgan
- Department of Osteology and Biomechanics, University Medical Center Hamburg-Eppendorf, 20246, Hamburg, Germany
| | - Tim Rolvien
- Department of Trauma and Orthopedic Surgery, University Medical Center Hamburg-Eppendorf, 20246, Hamburg, Germany.
| | - Thorsten Schinke
- Department of Osteology and Biomechanics, University Medical Center Hamburg-Eppendorf, 20246, Hamburg, Germany.
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Hendrickx G, Boudin E, Mateiu L, Yorgan TA, Steenackers E, Kneissel M, Kramer I, Mortier G, Schinke T, Van Hul W. An Additional Lrp4 High Bone Mass Mutation Mitigates the Sost-Knockout Phenotype in Mice by Increasing Bone Remodeling. Calcif Tissue Int 2024; 114:171-181. [PMID: 38051321 DOI: 10.1007/s00223-023-01158-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/10/2023] [Accepted: 10/31/2023] [Indexed: 12/07/2023]
Abstract
Pathogenic variants disrupting the binding between sclerostin (encoded by SOST) and its receptor LRP4 have previously been described to cause sclerosteosis, a rare high bone mass disorder. The sclerostin-LRP4 complex inhibits canonical WNT signaling, a key pathway regulating osteoblastic bone formation and a promising therapeutic target for common bone disorders, such as osteoporosis. In the current study, we crossed mice deficient for Sost (Sost-/-) with our p.Arg1170Gln Lrp4 knock-in (Lrp4KI/KI) mouse model to create double mutant Sost-/-;Lrp4KI/KI mice. We compared the phenotype of Sost-/- mice with that of Sost-/-;Lrp4KI/KI mice, to investigate a possible synergistic effect of the disease-causing p.Arg1170Trp variant in Lrp4 on Sost deficiency. Interestingly, presence of Lrp4KI alleles partially mitigated the Sost-/- phenotype. Cellular and dynamic histomorphometry did not reveal mechanistic insights into the observed phenotypic differences. We therefore determined the molecular effect of the Lrp4KI allele by performing bulk RNA sequencing on Lrp4KI/KI primary osteoblasts. Unexpectedly, mostly genes related to bone resorption or remodeling (Acp5, Rankl, Mmp9) were upregulated in Lrp4KI/KI primary osteoblasts. Verification of these markers in Lrp4KI/KI, Sost-/- and Sost-/-;Lrp4KI/KI mice revealed that sclerostin deficiency counteracts this Lrp4KI/KI effect in Sost-/-;Lrp4KI/KI mice. We therefore hypothesize that models with two inactivating Lrp4KI alleles rather activate bone remodeling, with a net gain in bone mass, whereas sclerostin deficiency has more robust anabolic effects on bone formation. Moreover, these effects of sclerostin and Lrp4 are stronger in female mice, contributing to a more severe phenotype than in males and more detectable phenotypic differences among different genotypes.
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Affiliation(s)
- Gretl Hendrickx
- Centre for Medical Genetics, University and University Hospital of Antwerp, Antwerp, Belgium
- Department of Human Genetics, KU Leuven, Louvain, Belgium
| | - Eveline Boudin
- Centre for Medical Genetics, University and University Hospital of Antwerp, Antwerp, Belgium
| | - Ligia Mateiu
- Centre for Medical Genetics, University and University Hospital of Antwerp, Antwerp, Belgium
| | - Timur A Yorgan
- Department of Osteology and Biomechanics, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Ellen Steenackers
- Centre for Medical Genetics, University and University Hospital of Antwerp, Antwerp, Belgium
| | - Michaela Kneissel
- Diseases of Aging and Regenerative Medicine, Novartis Institutes for BioMedical Research, Basel, Switzerland
| | - Ina Kramer
- Diseases of Aging and Regenerative Medicine, Novartis Institutes for BioMedical Research, Basel, Switzerland
| | - Geert Mortier
- Centre for Medical Genetics, University and University Hospital of Antwerp, Antwerp, Belgium
- Department of Human Genetics, KU Leuven, Louvain, Belgium
| | - Thorsten Schinke
- Department of Osteology and Biomechanics, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Wim Van Hul
- Centre for Medical Genetics, University and University Hospital of Antwerp, Antwerp, Belgium.
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Danyukova T, Alimy AR, Velho RV, Yorgan TA, Di Lorenzo G, von Kroge S, Tidow H, Wiegert JS, Hermans-Borgmeyer I, Schinke T, Rolvien T, Pohl S. Mice heterozygous for an osteogenesis imperfecta-linked MBTPS2 variant display a compromised subchondral osteocyte lacunocanalicular network associated with abnormal articular cartilage. Bone 2023; 177:116927. [PMID: 37797712 DOI: 10.1016/j.bone.2023.116927] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/03/2023] [Revised: 09/20/2023] [Accepted: 10/02/2023] [Indexed: 10/07/2023]
Abstract
Missense variants in the MBTPS2 gene, located on the X chromosome, have been associated with an X-linked recessive form of osteogenesis imperfecta (X-OI), an inherited bone dysplasia characterized by multiple and recurrent bone fractures, short stature, and various skeletal deformities in affected individuals. The role of site-2 protease, encoded by MBTPS2, and the molecular pathomechanism underlying the disease are to date elusive. This study is the first to report on the generation of two Mbtps2 mouse models, a knock-in mouse carrying one of the disease-causative MBTPS2 variants (N455S) and a Mbtps2 knock-out (ko) mouse. Because both loss-of-function variants lead to embryonic lethality in hemizygous male mutant mice, we performed a comprehensive skeletal analysis of heterozygous Mbtps2+/N455S and Mbtps2+/ko female mice. Both models displayed osteochondral abnormalities such as thinned subchondral bone, altered subchondral osteocyte interconnectivity as well as thickened articular cartilage with chondrocyte clustering, altogether resembling an early osteoarthritis (OA) phenotype. However, distant from the joints, no alterations in the bone mass and turnover could be detected in either of the mutant mice. Based on our findings we conclude that MBTPS2 haploinsufficiency results in early OA-like alterations in the articular cartilage and underlying subchondral bone, which likely precede the development of typical OI phenotype in bone. Our study provides first evidence for a potential role of site-2 protease for maintaining homeostasis of both bone and cartilage.
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Affiliation(s)
- Tatyana Danyukova
- Department of Osteology and Biomechanics, University Medical Center Hamburg-Eppendorf, 20246 Hamburg, Germany.
| | - Assil-Ramin Alimy
- Department of Trauma and Orthopedic Surgery, University Medical Center Hamburg-Eppendorf, 20246 Hamburg, Germany.
| | - Renata Voltolini Velho
- Department of Osteology and Biomechanics, University Medical Center Hamburg-Eppendorf, 20246 Hamburg, Germany.
| | - Timur A Yorgan
- Department of Osteology and Biomechanics, University Medical Center Hamburg-Eppendorf, 20246 Hamburg, Germany.
| | - Giorgia Di Lorenzo
- Department of Osteology and Biomechanics, University Medical Center Hamburg-Eppendorf, 20246 Hamburg, Germany.
| | - Simon von Kroge
- Department of Osteology and Biomechanics, University Medical Center Hamburg-Eppendorf, 20246 Hamburg, Germany; Department of Trauma and Orthopedic Surgery, University Medical Center Hamburg-Eppendorf, 20246 Hamburg, Germany.
| | - Henning Tidow
- The Hamburg Advanced Research Center for Bioorganic Chemistry (HARBOR), Department of Chemistry, Institute for Biochemistry and Molecular Biology, University of Hamburg, 20146 Hamburg, Germany.
| | - J Simon Wiegert
- Center for Molecular Neurobiology Hamburg, University Medical Center Hamburg-Eppendorf, 20251 Hamburg, Germany.
| | - Irm Hermans-Borgmeyer
- Center for Molecular Neurobiology Hamburg, University Medical Center Hamburg-Eppendorf, 20251 Hamburg, Germany
| | - Thorsten Schinke
- Department of Osteology and Biomechanics, University Medical Center Hamburg-Eppendorf, 20246 Hamburg, Germany.
| | - Tim Rolvien
- Department of Trauma and Orthopedic Surgery, University Medical Center Hamburg-Eppendorf, 20246 Hamburg, Germany.
| | - Sandra Pohl
- Department of Osteology and Biomechanics, University Medical Center Hamburg-Eppendorf, 20246 Hamburg, Germany.
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Wiedemann P, Schmidt FN, Amling M, Yorgan TA, Barvencik F. Zinc and vitamin D deficiency and supplementation in hypophosphatasia patients - A retrospective study. Bone 2023; 175:116849. [PMID: 37487860 DOI: 10.1016/j.bone.2023.116849] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/02/2023] [Revised: 07/07/2023] [Accepted: 07/14/2023] [Indexed: 07/26/2023]
Abstract
Hypophosphatasia (HPP) is characterized by severe skeletal symptoms including mineralization defects, insufficiency fractures, and delayed facture healing or non-unions. HPP is caused by mutations of the tissue non-specific alkaline phosphatase (TNSALP). Zinc is a cofactor of TNSALP and vitamin D an important regulator of bone matrix mineralization. Data from this retrospective study indicates that deficiencies in zinc or vitamin D occur in HPP patients with a similar frequency as in the general population. While guidelines for repletion of these micronutrients have been established for the general population, the transferability of the efficacy and safety of these regiments to HPP patients still needed to be determined. We filtered for variant classification (ACMG 3-5, non-benign) and data completeness from a total cohort of 263 HPP patients. 73.5 % of this sub-cohort were vitamin D deficient while 27.2 % were zinc deficient. We retrospectively evaluated the effect of supplementation according to general guidelines in 10 patients with zinc-deficiency and 38 patients with vitamin d-deficiency. The treatments significantly raised serum zinc or vitamin D levels respectively. All other assessed disease markers (alkaline phosphatase, pyrodoxal-5-phosphate) or bone turnover markers (phosphate, calcium, parathyroid hormone, bone specific alkaline phosphatase, creatinine, desoxypyridinoline) remained unchanged. These results highlight that general guidelines for zinc and vitamin D repletion can be successfully applied to HPP patients in order to prevent deficiency symptoms without exacerbating the disease burden or causing adverse effects due to changes in bone and calcium homeostasis.
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Affiliation(s)
- Philip Wiedemann
- Department of Osteology and Biomechanics, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Felix N Schmidt
- Department of Osteology and Biomechanics, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Michael Amling
- Department of Osteology and Biomechanics, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Timur A Yorgan
- Department of Osteology and Biomechanics, University Medical Center Hamburg-Eppendorf, Hamburg, Germany.
| | - Florian Barvencik
- Department of Osteology and Biomechanics, University Medical Center Hamburg-Eppendorf, Hamburg, Germany.
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5
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Schäfer P, Muhs S, Turnbull L, Garwal P, Maar H, Yorgan TA, Tolosa E, Lange T, Windhorst S. Ex Vivo Model of Neuroblastoma Plasticity. Cancers (Basel) 2023; 15:cancers15041274. [PMID: 36831616 PMCID: PMC9954615 DOI: 10.3390/cancers15041274] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2023] [Revised: 02/10/2023] [Accepted: 02/11/2023] [Indexed: 02/19/2023] Open
Abstract
Tumor plasticity is essential for adaptation to changing environmental conditions, in particular during the process of metastasis. In this study, we compared morphological and biochemical differences between LAN-1 neuroblastoma (NB) cells recovered from a subcutaneous xenograft primary tumor (PT) and the corresponding three generations of bone metastasis (BM I-III). Moreover, growth behavior, as well as the response to chemotherapy and immune cells were assessed. For this purpose, F-actin was stained, mRNA and protein expression assessed, and lactate secretion analyzed. Further, we measured adhesion to collagen I, the growth rate of spheroids in the presence and absence of vincristine, and the production of IL-6 by peripheral blood mononuclear cells (PBMCs) co-incubated with PT or BM I-III. Analysis of PT and the three BM generations revealed that their growth rate decreased from PT to BM III, and accordingly, PT cells reacted most sensitively to vincristine. In addition, morphology, adaption to hypoxic conditions, as well as transcriptomes showed strong differences between the cell lines. Moreover, BM I and BM II cells exhibited a significantly different ability to stimulate human immune cells compared to PT and BM III cells. Interestingly, the differences in immune cell stimulation corresponded to the expression level of the cancer-testis antigen MAGE-A3. In conclusion, our ex vivo model allows to analyze the adaption of tumor populations to different microenvironments and clearly demonstrates the strong alteration of tumor cell populations during this process.
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Affiliation(s)
- Paula Schäfer
- Department of Biochemistry and Signal Transduction, University Medical Center Hamburg-Eppendorf, Martinistrasse 52, D-20246 Hamburg, Germany
| | - Stefanie Muhs
- Department of Biochemistry and Signal Transduction, University Medical Center Hamburg-Eppendorf, Martinistrasse 52, D-20246 Hamburg, Germany
| | - Lucas Turnbull
- Department of Biochemistry and Signal Transduction, University Medical Center Hamburg-Eppendorf, Martinistrasse 52, D-20246 Hamburg, Germany
| | - Palwasha Garwal
- Department of Biochemistry and Signal Transduction, University Medical Center Hamburg-Eppendorf, Martinistrasse 52, D-20246 Hamburg, Germany
| | - Hanna Maar
- Institute of Anatomy and Experimental Morphology, University Medical Center Hamburg-Eppendorf, Martinistrasse 52, D-20246 Hamburg, Germany
| | - Timur A. Yorgan
- Department of Osteology and Biomechanics, University Medical Center Hamburg-Eppendorf, Martinistrasse 52, D-20246 Hamburg, Germany
| | - Eva Tolosa
- Department of Immunology, University Medical Center Hamburg-Eppendorf, Martinistrasse 52, D-20246 Hamburg, Germany
| | - Tobias Lange
- Institute of Anatomy and Experimental Morphology, University Medical Center Hamburg-Eppendorf, Martinistrasse 52, D-20246 Hamburg, Germany
- Institute of Anatomy I, Jena University Hospital, Teichgraben 7, D-07743 Jena, Germany
| | - Sabine Windhorst
- Department of Biochemistry and Signal Transduction, University Medical Center Hamburg-Eppendorf, Martinistrasse 52, D-20246 Hamburg, Germany
- Correspondence: ; Tel.: +49-40-7410-56013
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Delsmann MM, Peichl J, Yorgan TA, Beil FT, Amling M, Demay MB, Rolvien T. Prevention of Hypomineralization In Auditory Ossicles of Vitamin D Receptor (Vdr) Deficient Mice. Front Endocrinol (Lausanne) 2022; 13:901265. [PMID: 35733772 PMCID: PMC9207527 DOI: 10.3389/fendo.2022.901265] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/21/2022] [Accepted: 04/21/2022] [Indexed: 11/20/2022] Open
Abstract
Intact mineralization of the auditory ossicles - the smallest bones in the body - is essential for sound transmission in the middle ear, while ossicular hypomineralization is associated with conductive hearing loss. Here, we performed a high-resolution analysis of the ossicles in vitamin D receptor deficient mice (Vdr-/- ), which are characterized by hypocalcemia and skeletal mineralization defects, and investigated whether local hypomineralization can be prevented by feeding a calcium-rich rescue diet (Vdr-/- res ). In Vdr-/- mice fed a regular diet (Vdr-/- reg ), quantitative backscattered electron imaging (qBEI) revealed an increased void volume (porosity, p<0.0001) along with lower mean calcium content (CaMean, p=0.0008) and higher heterogeneity of mineralization (CaWidth, p=0.003) compared to WT mice. Furthermore, a higher osteoid volume per bone volume (OV/BV; p=0.0002) and a higher osteocyte lacunar area (Lc.Ar; p=0.01) were found in histomorphometric analysis in Vdr-/- reg mice. In Vdr-/- res mice, full rescue of OV/BV and Lc.Ar (both p>0.05 vs. WT) and partial rescue of porosity and CaWidth (p=0.02 and p=0.04 vs. WT) were observed. Compared with Hyp mice, a model of X-linked hypophosphatemic rickets, Vdr-/- reg mice showed a lower osteoid volume in the ossicles (p=0.0002), but similar values in the lumbar spine. These results are consistent with later postnatal impairment of mineral homeostasis in Vdr-/- mice than in Hyp mice, underscoring the importance of intact mineral homeostasis for ossicle mineralization during development. In conclusion, we revealed a distinct phenotype of hypomineralization in the auditory ossicles of Vdr-/- mice that can be partially prevented by a rescue diet. Since a positive effect of a calcium-rich diet on ossicular mineralization was demonstrated, our results open new treatment strategies for conductive hearing loss. Future studies should investigate the impact of improved ossicular mineralization on hearing function.
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Affiliation(s)
- Maximilian M. Delsmann
- Department of Trauma and Orthopaedic Surgery, Division of Orthopaedics, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
- Department of Osteology and Biomechanics, University Medical Center Hamburg Eppendorf, Hamburg, Germany
| | - Jonathan Peichl
- Department of Otorhinolaryngology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Timur A. Yorgan
- Department of Osteology and Biomechanics, University Medical Center Hamburg Eppendorf, Hamburg, Germany
| | - Frank Timo Beil
- Department of Trauma and Orthopaedic Surgery, Division of Orthopaedics, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Michael Amling
- Department of Osteology and Biomechanics, University Medical Center Hamburg Eppendorf, Hamburg, Germany
| | - Marie B. Demay
- Endocrine Unit, Massachusetts General Hospital, Harvard Medical School, Boston, MA, United States
| | - Tim Rolvien
- Department of Trauma and Orthopaedic Surgery, Division of Orthopaedics, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
- *Correspondence: Tim Rolvien,
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7
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Westermann LM, Fleischhauer L, Vogel J, Jenei-Lanzl Z, Ludwig NF, Schau L, Morellini F, Baranowsky A, Yorgan TA, Di Lorenzo G, Schweizer M, de Souza Pinheiro B, Guarany NR, Sperb-Ludwig F, Visioli F, Oliveira Silva T, Soul J, Hendrickx G, Wiegert JS, Schwartz IVD, Clausen-Schaumann H, Zaucke F, Schinke T, Pohl S, Danyukova T. Imbalanced cellular metabolism compromises cartilage homeostasis and joint function in a mouse model of mucolipidosis type III gamma. Dis Model Mech 2020; 13:dmm046425. [PMID: 33023972 PMCID: PMC7687858 DOI: 10.1242/dmm.046425] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2020] [Accepted: 09/15/2020] [Indexed: 11/23/2022] Open
Abstract
Mucolipidosis type III (MLIII) gamma is a rare inherited lysosomal storage disorder caused by mutations in GNPTG encoding the γ-subunit of GlcNAc-1-phosphotransferase, the key enzyme ensuring proper intracellular location of multiple lysosomal enzymes. Patients with MLIII gamma typically present with osteoarthritis and joint stiffness, suggesting cartilage involvement. Using Gnptg knockout (Gnptgko ) mice as a model of the human disease, we showed that missorting of a number of lysosomal enzymes is associated with intracellular accumulation of chondroitin sulfate in Gnptgko chondrocytes and their impaired differentiation, as well as with altered microstructure of the cartilage extracellular matrix (ECM). We also demonstrated distinct functional and structural properties of the Achilles tendons isolated from Gnptgko and Gnptab knock-in (Gnptabki ) mice, the latter displaying a more severe phenotype resembling mucolipidosis type II (MLII) in humans. Together with comparative analyses of joint mobility in MLII and MLIII patients, these findings provide a basis for better understanding of the molecular reasons leading to joint pathology in these patients. Our data suggest that lack of GlcNAc-1-phosphotransferase activity due to defects in the γ-subunit causes structural changes within the ECM of connective and mechanosensitive tissues, such as cartilage and tendon, and eventually results in functional joint abnormalities typically observed in MLIII gamma patients. This idea was supported by a deficit of the limb motor function in Gnptgko mice challenged on a rotarod under fatigue-associated conditions, suggesting that the impaired motor performance of Gnptgko mice was caused by fatigue and/or pain at the joint.This article has an associated First Person interview with the first author of the paper.
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Affiliation(s)
- Lena Marie Westermann
- Department of Osteology and Biomechanics, University Medical Center Hamburg-Eppendorf, 20246 Hamburg, Germany
| | - Lutz Fleischhauer
- Laboratory of Experimental Surgery and Regenerative Medicine, Clinic for General Trauma and Reconstructive Surgery, Ludwig-Maximilians University, 80336 Munich, Germany
- Center for Applied Tissue Engineering and Regenerative Medicine (Canter), University of Applied Sciences, 80533 Munich, Germany
| | - Jonas Vogel
- Center for Applied Tissue Engineering and Regenerative Medicine (Canter), University of Applied Sciences, 80533 Munich, Germany
| | - Zsuzsa Jenei-Lanzl
- Dr. Rolf M. Schwiete Research Unit for Osteoarthritis, Orthopedic University Hospital Friedrichsheim gGmbH, 60528 Frankfurt/Main, Germany
| | - Nataniel Floriano Ludwig
- Post-Graduate Program in Genetics and Molecular Biology, Federal University of Rio Grande do Sul, 90040-060 Porto Alegre, Brazil
| | - Lynn Schau
- RG Behavioral Biology, Center for Molecular Neurobiology Hamburg (ZMNH), University Medical Center Hamburg-Eppendorf, 20251 Hamburg, Germany
| | - Fabio Morellini
- RG Behavioral Biology, Center for Molecular Neurobiology Hamburg (ZMNH), University Medical Center Hamburg-Eppendorf, 20251 Hamburg, Germany
| | - Anke Baranowsky
- Department of Osteology and Biomechanics, University Medical Center Hamburg-Eppendorf, 20246 Hamburg, Germany
| | - Timur A Yorgan
- Department of Osteology and Biomechanics, University Medical Center Hamburg-Eppendorf, 20246 Hamburg, Germany
| | - Giorgia Di Lorenzo
- Department of Osteology and Biomechanics, University Medical Center Hamburg-Eppendorf, 20246 Hamburg, Germany
| | - Michaela Schweizer
- Center for Molecular Neurobiology Hamburg (ZMNH), University Medical Center Hamburg-Eppendorf, 20251 Hamburg, Germany
| | - Bruna de Souza Pinheiro
- Department of Genetics, Federal University of Rio Grande do Sul, 90040-060 Porto Alegre, Brazil
| | - Nicole Ruas Guarany
- Occupational Therapy Faculty, Federal University of Pelotas, 96010-610 Pelotas, Brazil
| | - Fernanda Sperb-Ludwig
- Department of Genetics, Federal University of Rio Grande do Sul, 90040-060 Porto Alegre, Brazil
| | - Fernanda Visioli
- Pathology Department, Federal University of Rio Grande do Sul, 90040-060 Porto Alegre, Brazil
| | - Thiago Oliveira Silva
- Post-Graduate Program in Medicine: Medical Sciences, Federal University of Rio Grande do Sul, 90040-060 Porto Alegre, Brazil
| | - Jamie Soul
- Skeletal Research Group, Biosciences Institute, Newcastle University, Newcastle upon Tyne NE1 3BZ, UK
| | - Gretl Hendrickx
- Department of Osteology and Biomechanics, University Medical Center Hamburg-Eppendorf, 20246 Hamburg, Germany
| | - J Simon Wiegert
- RG Synaptic Wiring and Information Processing, Center for Molecular Neurobiology Hamburg (ZMNH), University Medical Center Hamburg-Eppendorf, 20251 Hamburg, Germany
| | - Ida V D Schwartz
- Department of Genetics, Federal University of Rio Grande do Sul, 90040-060 Porto Alegre, Brazil
- Post-Graduate Program in Medicine: Medical Sciences, Federal University of Rio Grande do Sul, 90040-060 Porto Alegre, Brazil
| | - Hauke Clausen-Schaumann
- Center for Applied Tissue Engineering and Regenerative Medicine (Canter), University of Applied Sciences, 80533 Munich, Germany
| | - Frank Zaucke
- Dr. Rolf M. Schwiete Research Unit for Osteoarthritis, Orthopedic University Hospital Friedrichsheim gGmbH, 60528 Frankfurt/Main, Germany
| | - Thorsten Schinke
- Department of Osteology and Biomechanics, University Medical Center Hamburg-Eppendorf, 20246 Hamburg, Germany
| | - Sandra Pohl
- Department of Osteology and Biomechanics, University Medical Center Hamburg-Eppendorf, 20246 Hamburg, Germany
| | - Tatyana Danyukova
- Department of Osteology and Biomechanics, University Medical Center Hamburg-Eppendorf, 20246 Hamburg, Germany
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Rolvien T, Yorgan TA, Kornak U, Hermans-Borgmeyer I, Mundlos S, Schmidt T, Niemeier A, Schinke T, Amling M, Oheim R. Skeletal deterioration in COL2A1-related spondyloepiphyseal dysplasia occurs prior to the development of osteoarthritis. Bone Rep 2020. [DOI: 10.1016/j.bonr.2020.100598] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
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9
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Rolvien T, Yorgan TA, Kornak U, Hermans-Borgmeyer I, Mundlos S, Schmidt T, Niemeier A, Schinke T, Amling M, Oheim R. Skeletal deterioration in COL2A1-related spondyloepiphyseal dysplasia occurs prior to osteoarthritis. Osteoarthritis Cartilage 2020; 28:334-343. [PMID: 31958497 DOI: 10.1016/j.joca.2019.12.011] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/10/2019] [Revised: 11/05/2019] [Accepted: 12/31/2019] [Indexed: 02/02/2023]
Abstract
OBJECTIVE Spondyloepiphyseal dysplasia, a combination of progressive arthropathy with variable signs of skeletal dysplasia, can be a result of mutations in the collagen, type II, alpha 1 (COL2A1) gene. However, the bone involvement (e.g., density, microstructure) in this disorder has hitherto not been studied. DESIGN A 50-year-old female patient and her 8-year-old son with flattening of vertebral bodies and early-onset osteoarthritis were genetically tested using a custom designed gene bone panel including 386 genes. Bone microstructure and turnover were assessed using high-resolution peripheral quantitative computed tomography (HR-pQCT) and serum bone turnover markers, respectively. Furthermore, the bone and cartilage phenotype of male mice heterozygous for the loss-of-function mutation of Col2a1 (Col2a1+/d) was analyzed compared to wildtype littermates using μ-CT and histomorphometry. RESULTS We identified a dominant COL2A1 mutation (c.620G > A p.(Gly207Glu)) indicating spondyloepiphyseal dysplasia in the female patient and her son, both being severely affected by skeletal deterioration. Although there was no osteoarthritis detectable at first visit, the son was affected by trabecular osteopenia, which progressed over time. In an iliac crest biopsy obtained from the mother, osteoclast indices were remarkably increased. Col2a1+/d mice developed a moderate skeletal phenotype expressed by reduced cortical and trabecular parameters at 4 weeks. Importantly, no articular defects could be observed in the knee joints at 4 weeks, while osteoarthritis was only detectable in 12-week-old mice. CONCLUSIONS Our results indicate that collagen type II deficiency in spondyloepiphyseal dysplasia leads to skeletal deterioration with early-onset in humans and mice that occurs prior to the development of osteoarthritis.
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Affiliation(s)
- T Rolvien
- Department of Osteology and Biomechanics, University Medical Center Hamburg-Eppendorf, Lottestr. 59, 22529, Hamburg, Germany; Department of Orthopedics, University Medical Center Hamburg-Eppendorf, Hamburg, Germany.
| | - T A Yorgan
- Department of Osteology and Biomechanics, University Medical Center Hamburg-Eppendorf, Lottestr. 59, 22529, Hamburg, Germany
| | - U Kornak
- Institute of Medical Genetics and Human Genetics, Charité-Universitätsmedizin Berlin, Berlin, Germany; Berlin-Brandenburg School for Regenerative Therapies, Charité-Universitätsmedizin Berlin, Berlin, Germany; Max Planck Institute for Molecular Genetics, FG Development and Disease, Berlin, Germany
| | - I Hermans-Borgmeyer
- Center for Molecular Neurobiology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - S Mundlos
- Institute of Medical Genetics and Human Genetics, Charité-Universitätsmedizin Berlin, Berlin, Germany; Berlin-Brandenburg School for Regenerative Therapies, Charité-Universitätsmedizin Berlin, Berlin, Germany; Max Planck Institute for Molecular Genetics, FG Development and Disease, Berlin, Germany
| | - T Schmidt
- Department of Osteology and Biomechanics, University Medical Center Hamburg-Eppendorf, Lottestr. 59, 22529, Hamburg, Germany
| | - A Niemeier
- Department of Orthopedics, University Medical Center Hamburg-Eppendorf, Hamburg, Germany; Department of Biochemistry and Molecular Cell Biology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - T Schinke
- Department of Osteology and Biomechanics, University Medical Center Hamburg-Eppendorf, Lottestr. 59, 22529, Hamburg, Germany
| | - M Amling
- Department of Osteology and Biomechanics, University Medical Center Hamburg-Eppendorf, Lottestr. 59, 22529, Hamburg, Germany
| | - R Oheim
- Department of Osteology and Biomechanics, University Medical Center Hamburg-Eppendorf, Lottestr. 59, 22529, Hamburg, Germany
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10
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Yorgan TA, Peters S, Amling M, Schinke T. Osteoblast-specific expression of Panx3 is dispensable for postnatal bone remodeling. Bone 2019; 127:155-163. [PMID: 31202927 DOI: 10.1016/j.bone.2019.06.008] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/26/2019] [Revised: 06/07/2019] [Accepted: 06/12/2019] [Indexed: 12/11/2022]
Abstract
Since cost-effective osteoanabolic treatment options remain to be established, it is relevant to identify specific molecules physiologically regulating osteoblast differentiation and/or activity that are principally accessible as drug targets. Specific or predominant gene expression in a given cell type often predicts a relevant function in the respective tissue. Thus, we aimed to identify genes encoding membrane-associated proteins with selective expression in differentiated osteoblasts. We therefore applied an unbiased approach, i.e. Affymetrix Gene Chip hybridization, to compare global gene expression in primary murine osteoblasts at two stages of differentiation. For the most strongly induced genes we analyzed their expression pattern in different tissues, which led us to identify known and unknown osteoblast differentiation markers with predominant expression in bone. One of these genes was Panx3, encoding a transmembrane hemichannel with ill-defined function in skeletal remodeling. To decipher the role of Panx3 in osteoblasts we first generated Panx3-fl/fl mice carrying a Runx2-Cre transgene. Using undecalcified histology followed by bone-specific histomorphometry we did not observe any significant difference between 24 weeks old Cre-negative and Cre-positive littermates. We additionally generated and analyzed mice with ubiquitous Panx3 deletion, where a delay of endochondral ossification did not translate into a detectable skeletal phenotype after weaning, possibly explained by compensatory induction of Panx1. Of note, newborn Panx3-deficient mice displayed significantly reduced serum glucose levels, which was not the case in older animals. Our findings demonstrate that Panx3 expression in osteoblasts is not required for postnatal bone remodeling, which essentially rules out its suitability as a target protein for osteoanabolic medication.
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Affiliation(s)
- Timur A Yorgan
- Department of Osteology and Biomechanics, University Medical Center Hamburg Eppendorf, Hamburg 20246, Germany
| | - Stephanie Peters
- Department of Osteology and Biomechanics, University Medical Center Hamburg Eppendorf, Hamburg 20246, Germany
| | - Michael Amling
- Department of Osteology and Biomechanics, University Medical Center Hamburg Eppendorf, Hamburg 20246, Germany
| | - Thorsten Schinke
- Department of Osteology and Biomechanics, University Medical Center Hamburg Eppendorf, Hamburg 20246, Germany.
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11
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Schmidt FN, Delsmann MM, Mletzko K, Yorgan TA, Hahn M, Siebert U, Busse B, Oheim R, Amling M, Rolvien T. Ultra-high matrix mineralization of sperm whale auditory ossicles facilitates high sound pressure and high-frequency underwater hearing. Proc Biol Sci 2019; 285:20181820. [PMID: 30963901 DOI: 10.1098/rspb.2018.1820] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
The auditory ossicles-malleus, incus and stapes-are the smallest bones in mammalian bodies and enable stable sound transmission to the inner ear. Sperm whales are one of the deepest diving aquatic mammals that produce and perceive sounds with extreme loudness greater than 180 dB and frequencies higher than 30 kHz. Therefore, it is of major interest to decipher the microstructural basis for these unparalleled hearing abilities. Using a suite of high-resolution imaging techniques, we reveal that auditory ossicles of sperm whales are highly functional, featuring an ultra-high matrix mineralization that is higher than their teeth. On a micro-morphological and cellular level, this was associated with osteonal structures and osteocyte lacunar occlusions through calcified nanospherites (i.e. micropetrosis), while the bones were characterized by a higher hardness compared to a vertebral bone of the same animals as well as to human auditory ossicles. We propose that the ultra-high mineralization facilitates the unique hearing ability of sperm whales. High matrix mineralization represents an evolutionary conserved or convergent adaptation to middle ear sound transmission.
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Affiliation(s)
- Felix N Schmidt
- 1 Department of Osteology and Biomechanics, University Medical Center Hamburg-Eppendorf , Lottestrasse 59, 22529 Hamburg , Germany
| | - Maximilian M Delsmann
- 1 Department of Osteology and Biomechanics, University Medical Center Hamburg-Eppendorf , Lottestrasse 59, 22529 Hamburg , Germany
| | - Kathrin Mletzko
- 1 Department of Osteology and Biomechanics, University Medical Center Hamburg-Eppendorf , Lottestrasse 59, 22529 Hamburg , Germany
| | - Timur A Yorgan
- 1 Department of Osteology and Biomechanics, University Medical Center Hamburg-Eppendorf , Lottestrasse 59, 22529 Hamburg , Germany
| | - Michael Hahn
- 1 Department of Osteology and Biomechanics, University Medical Center Hamburg-Eppendorf , Lottestrasse 59, 22529 Hamburg , Germany
| | - Ursula Siebert
- 2 Institute for Terrestrial and Aquatic Wildlife Research, University of Veterinary Medicine Hannover , Foundation, Werftstrasse 6, 25761 Buesum , Germany
| | - Björn Busse
- 1 Department of Osteology and Biomechanics, University Medical Center Hamburg-Eppendorf , Lottestrasse 59, 22529 Hamburg , Germany
| | - Ralf Oheim
- 1 Department of Osteology and Biomechanics, University Medical Center Hamburg-Eppendorf , Lottestrasse 59, 22529 Hamburg , Germany
| | - Michael Amling
- 1 Department of Osteology and Biomechanics, University Medical Center Hamburg-Eppendorf , Lottestrasse 59, 22529 Hamburg , Germany
| | - Tim Rolvien
- 1 Department of Osteology and Biomechanics, University Medical Center Hamburg-Eppendorf , Lottestrasse 59, 22529 Hamburg , Germany.,3 Department of Orthopedics, University Medical Center Hamburg-Eppendorf , Martinistrasse 52, 20246 Hamburg , Germany
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12
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Pohl S, Angermann A, Jeschke A, Hendrickx G, Yorgan TA, Makrypidi-Fraune G, Steigert A, Kuehn SC, Rolvien T, Schweizer M, Koehne T, Neven M, Winter O, Velho RV, Albers J, Streichert T, Pestka JM, Baldauf C, Breyer S, Stuecker R, Muschol N, Cox TM, Saftig P, Paganini C, Rossi A, Amling M, Braulke T, Schinke T. The Lysosomal Protein Arylsulfatase B Is a Key Enzyme Involved in Skeletal Turnover. J Bone Miner Res 2018; 33:2186-2201. [PMID: 30075049 DOI: 10.1002/jbmr.3563] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/12/2018] [Revised: 06/10/2018] [Accepted: 06/20/2018] [Indexed: 12/24/2022]
Abstract
Skeletal pathologies are frequently observed in lysosomal storage disorders, yet the relevance of specific lysosomal enzymes in bone remodeling cell types is poorly defined. Two lysosomal enzymes, ie, cathepsin K (Ctsk) and Acp5 (also known as tartrate-resistant acid phosphatase), have long been known as molecular marker proteins of differentiated osteoclasts. However, whereas the cysteine protease Ctsk is directly involved in the degradation of bone matrix proteins, the molecular function of Acp5 in osteoclasts is still unknown. Here we show that Acp5, in concert with Acp2 (lysosomal acid phosphatase), is required for dephosphorylation of the lysosomal mannose 6-phosphate targeting signal to promote the activity of specific lysosomal enzymes. Using an unbiased approach we identified the glycosaminoglycan-degrading enzyme arylsulfatase B (Arsb), mutated in mucopolysaccharidosis type VI (MPS-VI), as an osteoclast marker, whose activity depends on dephosphorylation by Acp2 and Acp5. Similar to Acp2/Acp5-/- mice, Arsb-deficient mice display lysosomal storage accumulation in osteoclasts, impaired osteoclast activity, and high trabecular bone mass. Of note, the most prominent lysosomal storage accumulation was observed in osteocytes from Arsb-deficient mice, yet this pathology did not impair production of sclerostin (Sost) and Fgf23. Because the influence of enzyme replacement therapy (ERT) on bone remodeling in MPS-VI is still unknown, we additionally treated Arsb-deficient mice by weekly injection of recombinant human ARSB from 12 to 24 weeks of age. We found that the high bone mass phenotype of Arsb-deficient mice and the underlying bone cell deficits were fully corrected by ERT in the trabecular compartment. Taken together, our results do not only show that the function of Acp5 in osteoclasts is linked to dephosphorylation and activation of lysosomal enzymes, they also provide an important proof-of-principle for the feasibility of ERT to correct bone cell pathologies in lysosomal storage disorders. © 2018 The Authors. Journal of Bone and Mineral Research Published by Wiley Periodicals Inc.
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Affiliation(s)
- Sandra Pohl
- Department of Biochemistry, Children's Hospital, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Alexandra Angermann
- Department of Osteology and Biomechanics, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Anke Jeschke
- Department of Osteology and Biomechanics, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Gretl Hendrickx
- Department of Osteology and Biomechanics, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Timur A Yorgan
- Department of Osteology and Biomechanics, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Georgia Makrypidi-Fraune
- Department of Biochemistry, Children's Hospital, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Anita Steigert
- Department of Osteology and Biomechanics, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Sonja C Kuehn
- Department of Osteology and Biomechanics, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Tim Rolvien
- Department of Osteology and Biomechanics, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Michaela Schweizer
- Department of Electron Microscopy, Center of Molecular Neurobiology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Till Koehne
- Department of Osteology and Biomechanics, University Medical Center Hamburg-Eppendorf, Hamburg, Germany.,Department of Orthodontics, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Mona Neven
- Department of Osteology and Biomechanics, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Olga Winter
- Department of Osteology and Biomechanics, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Renata Voltolini Velho
- Department of Biochemistry, Children's Hospital, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Joachim Albers
- Department of Osteology and Biomechanics, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Thomas Streichert
- Department of Clinical Chemistry, University Hospital Cologne, Cologne, Germany
| | - Jan M Pestka
- Department of Osteology and Biomechanics, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Christina Baldauf
- Department of Osteology and Biomechanics, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Sandra Breyer
- Department of Orthopedics, Children's Hospital Hamburg-Altona, Hamburg, Germany
| | - Ralf Stuecker
- Department of Orthopedics, Children's Hospital Hamburg-Altona, Hamburg, Germany
| | - Nicole Muschol
- Department of Electron Microscopy, Center of Molecular Neurobiology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Timothy M Cox
- Department of Medicine, University of Cambridge, Cambridge, UK
| | - Paul Saftig
- Institute of Biochemistry, Christian-Albrechts-University, Kiel, Germany
| | - Chiara Paganini
- Department of Molecular Medicine, University of Pavia, Pavia, Italy
| | - Antonio Rossi
- Department of Molecular Medicine, University of Pavia, Pavia, Italy
| | - Michael Amling
- Department of Osteology and Biomechanics, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Thomas Braulke
- Department of Biochemistry, Children's Hospital, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Thorsten Schinke
- Department of Osteology and Biomechanics, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
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13
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Hendrickx G, Borra VM, Steenackers E, Yorgan TA, Hermans C, Boudin E, Waterval JJ, Jansen IDC, Aydemir TB, Kamerling N, Behets GJ, Plumeyer C, D’Haese PC, Busse B, Everts V, Lammens M, Mortier G, Cousins RJ, Schinke T, Stokroos RJ, Manni JJ, Van Hul W. Conditional mouse models support the role of SLC39A14 (ZIP14) in Hyperostosis Cranialis Interna and in bone homeostasis. PLoS Genet 2018; 14:e1007321. [PMID: 29621230 PMCID: PMC5903675 DOI: 10.1371/journal.pgen.1007321] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2017] [Revised: 04/17/2018] [Accepted: 03/19/2018] [Indexed: 01/19/2023] Open
Abstract
Hyperostosis Cranialis Interna (HCI) is a rare bone disorder characterized by progressive intracranial bone overgrowth at the skull. Here we identified by whole-exome sequencing a dominant mutation (L441R) in SLC39A14 (ZIP14). We show that L441R ZIP14 is no longer trafficked towards the plasma membrane and excessively accumulates intracellular zinc, resulting in hyper-activation of cAMP-CREB and NFAT signaling. Conditional knock-in mice overexpressing L438R Zip14 in osteoblasts have a severe skeletal phenotype marked by a drastic increase in cortical thickness due to an enhanced endosteal bone formation, resembling the underlying pathology in HCI patients. Remarkably, L438R Zip14 also generates an osteoporotic trabecular bone phenotype. The effects of osteoblastic overexpression of L438R Zip14 therefore mimic the disparate actions of estrogen on cortical and trabecular bone through osteoblasts. Collectively, we reveal ZIP14 as a novel regulator of bone homeostasis, and that manipulating ZIP14 might be a therapeutic strategy for bone diseases.
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Affiliation(s)
- Gretl Hendrickx
- Center of Medical Genetics, University and University Hospital of Antwerp, Antwerp, Belgium
| | - Vere M. Borra
- Center of Medical Genetics, University and University Hospital of Antwerp, Antwerp, Belgium
| | - Ellen Steenackers
- Center of Medical Genetics, University and University Hospital of Antwerp, Antwerp, Belgium
| | - Timur A. Yorgan
- Department of Osteology and Biomechanics (IOBM), University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Christophe Hermans
- Center for Oncological Research Antwerp (CORE), University of Antwerp, Antwerp, Belgium
| | - Eveline Boudin
- Center of Medical Genetics, University and University Hospital of Antwerp, Antwerp, Belgium
| | - Jérôme J. Waterval
- Department of Otorhinolaryngology, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Ineke D. C. Jansen
- Department of Periodontology and Oral Cell Biology, Academic Center of Dentistry Amsterdam and VU University Amsterdam, Amsterdam, The Netherlands
| | - Tolunay Beker Aydemir
- Food Science and Human Nutrition Department and Center for Nutritional Sciences, College of Agricultural and Life Sciences, University of Florida, Gainesville, FL, United States of America
| | - Niels Kamerling
- Department of Neurosurgery, University Hospital Antwerp, Antwerp, Belgium
| | - Geert J. Behets
- Department of Pathophysiology, University of Antwerp, Antwerp, Belgium
| | - Christine Plumeyer
- Department of Osteology and Biomechanics (IOBM), University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | | | - Björn Busse
- Department of Osteology and Biomechanics (IOBM), University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Vincent Everts
- Department of Periodontology and Oral Cell Biology, Academic Center of Dentistry Amsterdam and VU University Amsterdam, Amsterdam, The Netherlands
| | - Martin Lammens
- Department of Pathological Anatomy, University Hospital Antwerp, Antwerp, Belgium
| | - Geert Mortier
- Center of Medical Genetics, University and University Hospital of Antwerp, Antwerp, Belgium
| | - Robert J. Cousins
- Food Science and Human Nutrition Department and Center for Nutritional Sciences, College of Agricultural and Life Sciences, University of Florida, Gainesville, FL, United States of America
| | - Thorsten Schinke
- Department of Osteology and Biomechanics (IOBM), University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Robert J. Stokroos
- Department of Otorhinolaryngology and Head & Neck Surgery, Maastricht University Medical Center, Maastricht, The Netherlands
| | - Johannes J. Manni
- Department of Otorhinolaryngology and Head & Neck Surgery, Maastricht University Medical Center, Maastricht, The Netherlands
| | - Wim Van Hul
- Center of Medical Genetics, University and University Hospital of Antwerp, Antwerp, Belgium
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14
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Gioia R, Tonelli F, Ceppi I, Biggiogera M, Leikin S, Fisher S, Tenedini E, Yorgan TA, Schinke T, Tian K, Schwartz JM, Forte F, Wagener R, Villani S, Rossi A, Forlino A. The chaperone activity of 4PBA ameliorates the skeletal phenotype of Chihuahua, a zebrafish model for dominant osteogenesis imperfecta. Hum Mol Genet 2018; 26:2897-2911. [PMID: 28475764 PMCID: PMC5886106 DOI: 10.1093/hmg/ddx171] [Citation(s) in RCA: 56] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2017] [Accepted: 05/02/2017] [Indexed: 12/21/2022] Open
Abstract
Classical osteogenesis imperfecta (OI) is a bone disease caused by type I collagen mutations and characterized by bone fragility, frequent fractures in absence of trauma and growth deficiency. No definitive cure is available for OI and to develop novel drug therapies, taking advantage of a repositioning strategy, the small teleost zebrafish (Danio rerio) is a particularly appealing model. Its small size, high proliferative rate, embryo transparency and small amount of drug required make zebrafish the model of choice for drug screening studies, when a valid disease model is available. We performed a deep characterization of the zebrafish mutant Chihuahua, that carries a G574D (p.G736D) substitution in the α1 chain of type I collagen. We successfully validated it as a model for classical OI. Growth of mutants was delayed compared with WT. X-ray, µCT, alizarin red/alcian blue and calcein staining revealed severe skeletal deformity, presence of fractures and delayed mineralization. Type I collagen extracted from different tissues showed abnormal electrophoretic migration and low melting temperature. The presence of endoplasmic reticulum (ER) enlargement due to mutant collagen retention in osteoblasts and fibroblasts of mutant fish was shown by electron and confocal microscopy. Two chemical chaperones, 4PBA and TUDCA, were used to ameliorate the cellular stress and indeed 4PBA ameliorated bone mineralization in larvae and skeletal deformities in adult, mainly acting on reducing ER cisternae size and favoring collagen secretion. In conclusion, our data demonstrated that ER stress is a novel target to ameliorate OI phenotype; chemical chaperones such as 4PBA may be, alone or in combination, a new class of molecules to be further investigated for OI treatment.
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Affiliation(s)
- Roberta Gioia
- Department of Molecular Medicine, Biochemistry Unit, University of Pavia, Pavia, Italy
| | - Francesca Tonelli
- Department of Molecular Medicine, Biochemistry Unit, University of Pavia, Pavia, Italy
| | - Ilaria Ceppi
- Department of Molecular Medicine, Biochemistry Unit, University of Pavia, Pavia, Italy
| | - Marco Biggiogera
- Department of Biology and Biotechnology, University of Pavia, Pavia, Italy
| | - Sergey Leikin
- Section on Physical Biochemistry, Eunice Kennedy Shriver NICHD, NIH, Bethesda, MD, USA
| | - Shannon Fisher
- Department of Pharmacology & Experimental Therapeutics, Boston University School of Medicine, Boston, MA, USA
| | - Elena Tenedini
- Center for Genome Research, Department of Medical and Surgical Sciences, University of Modena and Reggio Emilia, Modena, Italy
| | - Timur A Yorgan
- Institute of Osteology and Biomechanic, Center for Experimental Medicine, University of Hamburg, Hamburg, Germany
| | - Thorsten Schinke
- Institute of Osteology and Biomechanic, Center for Experimental Medicine, University of Hamburg, Hamburg, Germany
| | - Kun Tian
- Faculty of Biology, Medicine and Health, University of Manchester, Manchester, UK
| | - Jean-Marc Schwartz
- Faculty of Biology, Medicine and Health, University of Manchester, Manchester, UK
| | - Fabiana Forte
- Medical Faculty, Center for Biochemistry, Center for Molecular Medicine, University of Cologne, Cologne, Germany
| | - Raimund Wagener
- Medical Faculty, Center for Biochemistry, Center for Molecular Medicine, University of Cologne, Cologne, Germany
| | - Simona Villani
- Department of Public Health and Experimental and Forensic Medicine, Unit of Biostatistics and Clinical Epidemiology, University of Pavia, Pavia, Italy
| | - Antonio Rossi
- Department of Molecular Medicine, Biochemistry Unit, University of Pavia, Pavia, Italy
| | - Antonella Forlino
- Department of Molecular Medicine, Biochemistry Unit, University of Pavia, Pavia, Italy
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15
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Brylka LJ, Köppert S, Babler A, Kratz B, Denecke B, Yorgan TA, Etich J, Costa IG, Brachvogel B, Boor P, Schinke T, Jahnen-Dechent W. Post-weaning epiphysiolysis causes distal femur dysplasia and foreshortened hindlimbs in fetuin-A-deficient mice. PLoS One 2017; 12:e0187030. [PMID: 29088242 PMCID: PMC5663435 DOI: 10.1371/journal.pone.0187030] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2017] [Accepted: 10/12/2017] [Indexed: 01/01/2023] Open
Abstract
Fetuin-A / α2-Heremans-Schmid-glycoprotein (gene name Ahsg) is a systemic inhibitor of ectopic calcification. Due to its high affinity for calcium phosphate, fetuin-A is highly abundant in mineralized bone matrix. Foreshortened femora in fetuin-A-deficient Ahsg-/- mice indicated a role for fetuin-A in bone formation. We studied early postnatal bone development in fetuin-A-deficient mice and discovered that femora from Ahsg-/- mice exhibited severely displaced distal epiphyses and deformed growth plates, similar to the human disease slipped capital femoral epiphysis (SCFE). The growth plate slippage occurred in 70% of Ahsg-/- mice of both sexes around three weeks postnatal. At this time point, mice weaned and rapidly gained weight and mobility. Epiphysis slippage never occurred in wildtype and heterozygous Ahsg+/- mice. Homozygous fetuin-A-deficient Ahsg-/- mice and, to a lesser degree, heterozygous Ahsg+/- mice showed lesions separating the proliferative zone from the hypertrophic zone of the growth plate. The hypertrophic growth plate cartilage in long bones from Ahsg-/- mice was significantly elongated and V-shaped until three weeks of age and thus prior to the slippage. Genome-wide transcriptome analysis of laser-dissected distal femoral growth plates from 13-day-old Ahsg-/- mice revealed a JAK-STAT-mediated inflammatory response including a 550-fold induction of the chemokine Cxcl9. At this stage, vascularization of the elongated growth plates was impaired, which was visualized by immunofluorescence staining. Thus, fetuin-A-deficient mice may serve as a rodent model of growth plate pathologies including SCFE and inflammatory cartilage degradation.
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Affiliation(s)
- Laura J. Brylka
- Biointerface Laboratory, Helmholtz Institute for Biomedical Engineering, RWTH Aachen University Hospital, Aachen, Germany
| | - Sina Köppert
- Biointerface Laboratory, Helmholtz Institute for Biomedical Engineering, RWTH Aachen University Hospital, Aachen, Germany
| | - Anne Babler
- Biointerface Laboratory, Helmholtz Institute for Biomedical Engineering, RWTH Aachen University Hospital, Aachen, Germany
| | - Beate Kratz
- IZKF Genomics Facility, Interdisciplinary Center for Clinical Research, RWTH Aachen University Hospital, Aachen, Germany
| | - Bernd Denecke
- IZKF Genomics Facility, Interdisciplinary Center for Clinical Research, RWTH Aachen University Hospital, Aachen, Germany
| | - Timur A. Yorgan
- Department of Osteology and Biomechanics, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Julia Etich
- Department of Pediatrics and Adolescent Medicine, Experimental Neonatology, Medical Faculty, University of Cologne, Cologne, Germany
- Center for Biochemistry, Medical Faculty, University of Cologne, Cologne, Germany
| | - Ivan G. Costa
- IZKF Research Group Computational Biology and Bioinformatics, Interdisciplinary Center for Clinical Research, RWTH Aachen University Hospital, Aachen, Germany
| | - Bent Brachvogel
- Department of Pediatrics and Adolescent Medicine, Experimental Neonatology, Medical Faculty, University of Cologne, Cologne, Germany
- Center for Biochemistry, Medical Faculty, University of Cologne, Cologne, Germany
| | - Peter Boor
- Department of Pathology & Division of Nephrology and Immunology, RWTH Aachen University Hospital, Aachen, Germany
| | - Thorsten Schinke
- Department of Osteology and Biomechanics, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Willi Jahnen-Dechent
- Biointerface Laboratory, Helmholtz Institute for Biomedical Engineering, RWTH Aachen University Hospital, Aachen, Germany
- * E-mail:
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16
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Yorgan TA, Heckt T, Rendenbach C, Helmis C, Seitz S, Streichert T, Amling M, Schinke T. Immediate effects of retinoic acid on gene expression in primary murine osteoblasts. J Bone Miner Metab 2016; 34:161-70. [PMID: 25956707 DOI: 10.1007/s00774-015-0666-2] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/18/2014] [Accepted: 02/16/2015] [Indexed: 10/23/2022]
Abstract
Consistent with clinical observations demonstrating that hypervitaminosis A is associated with increased skeletal fracture risk, we have previously found that dietary retinol deprivation partially corrects the bone mineralization defects in a mouse model of X-linked hypophosphatemic rickets. That retinol-dependent signaling pathways impact the skeleton is further supported by various findings demonstrating a negative influence of retinoic acid (RA) on bone-forming osteoblasts. We hypothesized that RA would directly regulate the expression of specific target genes in osteoblasts, and we aimed to identify these by genome-wide expression analyses. Here we show that high dietary retinol intake in mice causes low bone mass associated with increased osteoclastogenesis and decreased osteoblastogenesis, but intact bone matrix mineralization. We additionally found that short-term treatment of primary osteoblasts with RA causes a rapid induction of specific genes involved in either retinol-dependent signaling (i.e. Rara, Crabp2) or skeletal remodeling (i.e. Twist2, Tnfsf11). In contrast, neither expression of established osteoblast differentiation markers nor the proliferation rate was immediately affected by RA administration. Collectively, our data suggest that the negative effects of vitamin A on skeletal integrity are explainable by an immediate influence of RA signaling on specific genes in osteoblasts that in turn influence bone remodeling.
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Affiliation(s)
- Timur A Yorgan
- Department of Osteology and Biomechanics, University Medical Center Hamburg Eppendorf, Hamburg, Germany
| | - Timo Heckt
- Department of Osteology and Biomechanics, University Medical Center Hamburg Eppendorf, Hamburg, Germany
| | - Carsten Rendenbach
- Department of Osteology and Biomechanics, University Medical Center Hamburg Eppendorf, Hamburg, Germany
| | - Christina Helmis
- Department of Osteology and Biomechanics, University Medical Center Hamburg Eppendorf, Hamburg, Germany
| | - Sebastian Seitz
- Department of Osteology and Biomechanics, University Medical Center Hamburg Eppendorf, Hamburg, Germany
| | - Thomas Streichert
- Department of Clinical Chemistry, University Medical Center Hamburg Eppendorf, Hamburg, Germany
| | - Michael Amling
- Department of Osteology and Biomechanics, University Medical Center Hamburg Eppendorf, Hamburg, Germany
| | - Thorsten Schinke
- Department of Osteology and Biomechanics, University Medical Center Hamburg Eppendorf, Hamburg, Germany.
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17
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Kuehn SC, Koehne T, Cornils K, Markmann S, Riedel C, Pestka JM, Schweizer M, Baldauf C, Yorgan TA, Krause M, Keller J, Neven M, Breyer S, Stuecker R, Muschol N, Busse B, Braulke T, Fehse B, Amling M, Schinke T. Impaired bone remodeling and its correction by combination therapy in a mouse model of mucopolysaccharidosis-I. Hum Mol Genet 2015; 24:7075-86. [PMID: 26427607 DOI: 10.1093/hmg/ddv407] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2015] [Accepted: 09/22/2015] [Indexed: 01/21/2023] Open
Abstract
Mucopolysaccharidosis-I (MPS-I) is a lysosomal storage disease (LSD) caused by inactivating mutations of IDUA, encoding the glycosaminoglycan-degrading enzyme α-l-iduronidase. Although MPS-I is associated with skeletal abnormalities, the impact of IDUA deficiency on bone remodeling is poorly defined. Here we report that Idua-deficient mice progressively develop a high bone mass phenotype with pathological lysosomal storage in cells of the osteoblast lineage. Histomorphometric quantification identified shortening of bone-forming units and reduced osteoclast numbers per bone surface. This phenotype was not transferable into wild-type mice by bone marrow transplantation (BMT). In contrast, the high bone mass phenotype of Idua-deficient mice was prevented by BMT from wild-type donors. At the cellular level, BMT did not only normalize defects of Idua-deficient osteoblasts and osteocytes but additionally caused increased osteoclastogenesis. Based on clinical observations in an individual with MPS-I, previously subjected to BMT and enzyme replacement therapy (ERT), we treated Idua-deficient mice accordingly and found that combining both treatments normalized all histomorphometric parameters of bone remodeling. Our results demonstrate that BMT and ERT profoundly affect skeletal remodeling of Idua-deficient mice, thereby suggesting that individuals with MPS-I should be monitored for their bone remodeling status, before and after treatment, to avoid long-term skeletal complications.
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Affiliation(s)
| | - Till Koehne
- Department of Osteology and Biomechanics, Department of Orthodontics
| | - Kerstin Cornils
- Department of Stem Cell Transplantation, Research Department Cell and Gene Therapy
| | | | | | | | - Michaela Schweizer
- Center of Molecular Neurobiology, University Medical Center Hamburg-Eppendorf, Hamburg 20246, Germany and
| | | | | | | | | | - Mona Neven
- Department of Osteology and Biomechanics
| | - Sandra Breyer
- Children's Hospital Hamburg-Altona, Department of Orthopedics, University Clinic Hamburg, Hamburg 22763, Germany
| | - Ralf Stuecker
- Children's Hospital Hamburg-Altona, Department of Orthopedics, University Clinic Hamburg, Hamburg 22763, Germany
| | | | | | | | - Boris Fehse
- Department of Stem Cell Transplantation, Research Department Cell and Gene Therapy
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18
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Yorgan TA, Peters S, Jeschke A, Benisch P, Jakob F, Amling M, Schinke T. The Anti-Osteoanabolic Function of Sclerostin Is Blunted in Mice Carrying a High Bone Mass Mutation of Lrp5. J Bone Miner Res 2015; 30:1175-83. [PMID: 25640331 DOI: 10.1002/jbmr.2461] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/09/2014] [Revised: 12/23/2014] [Accepted: 01/13/2015] [Indexed: 12/17/2022]
Abstract
Activating mutations of the putative Wnt co-receptor Lrp5 or inactivating mutations of the secreted molecule Sclerostin cause excessive bone formation in mice and humans. Previous studies have suggested that Sclerostin functions as an Lrp5 antagonist, yet clear in vivo evidence was still missing, and alternative mechanisms have been discussed. Moreover, because osteoblast-specific inactivation of β-catenin, the major intracellular mediator of canonical Wnt signaling, primarily affected bone resorption, it remained questionable, whether Sclerostin truly acts as a Wnt signaling antagonist by interacting with Lrp5. In an attempt to address this relevant question, we generated a mouse model (Col1a1-Sost) with transgenic overexpression of Sclerostin under the control of a 2.3-kb Col1a1 promoter fragment. These mice displayed the expected low bone mass phenotype as a consequence of reduced bone formation. The Col1a1-Sost mice were then crossed with two mouse lines carrying different high bone mass mutations of Lrp5 (Lrp5(A170V) and Lrp5(G213V)), both of them potentially interfering with Sclerostin binding. Using µCT-scanning and histomorphometry we found that the anti-osteoanabolic influence of Sclerostin overexpression was not observed in Lrp5(A213V/A213V) mice and strongly reduced in Lrp5(A170V/A170V) mice. As a control we applied the same strategy with mice overexpressing the transmembrane Wnt signaling antagonist Krm2 and found that the anti-osteoanabolic influence of the Col1a1-Krm2 transgene was not affected by either of the Lrp5 mutations. Taken together, our data support the concept that Sclerostin inhibits bone formation through Lrp5 interaction, yet their physiological relevance remains to be established.
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Affiliation(s)
- Timur A Yorgan
- Department of Osteology and Biomechanics, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Stephanie Peters
- Department of Osteology and Biomechanics, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Anke Jeschke
- Department of Osteology and Biomechanics, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Peggy Benisch
- Orthopedic Center for Musculoskeletal Research, University of Wuerzburg, Wuerzburg, Germany
| | - Franz Jakob
- Orthopedic Center for Musculoskeletal Research, University of Wuerzburg, Wuerzburg, Germany
| | - Michael Amling
- Department of Osteology and Biomechanics, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Thorsten Schinke
- Department of Osteology and Biomechanics, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
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19
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Yorgan TA, Schinke T. Relevance of Wnt signaling for osteoanabolic therapy. Mol Cell Ther 2014; 2:22. [PMID: 26056589 PMCID: PMC4452071] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Figures] [Subscribe] [Scholar Register] [Received: 05/22/2014] [Accepted: 07/08/2014] [Indexed: 11/21/2023]
Abstract
The Wnt signaling pathway is long known to play fundamental roles in various aspects of embryonic development, but also in several homeostatic processes controlling tissue functions in adults. The complexity of this system is best underscored by the fact that the mammalian genome encodes for 19 different Wnt ligands, most but not all of them acting through an intracellular stabilization of β-catenin, representing the key molecule within the so-called canonical Wnt signaling pathway. Wnt ligands primarily bind to 10 different serpentine receptors of the Fzd family, and this binding can be positively or negatively regulated by additional molecules present at the surface of the respective target cells. One of these molecules is the transmembrane protein Lrp5, which has been shown to act as a Wnt co-receptor. In 2001, Lrp5, and thereby Wnt signaling, entered center stage in the research area of bone remodeling, a homeostatic process controlling bone mass, whose disturbance causes osteoporosis, one of the most prevalent disorders worldwide. More specifically, it was found that inactivating mutations of the human LRP5 gene cause osteoporosis-pseudoglioma syndrome, a rare genetic disorder characterized by impaired bone formation and persistence of hyaloid vessels in the eyeballs. In addition, activating LRP5 mutations were identified in individuals with osteosclerosis, a high bone mass condition characterized by excessive bone formation. Especially explained by the lack of cost-effective osteoanabolic treatment options, these findings had an immediate impact on the research regarding the bone-forming cell type, i.e. the osteoblast, whose differentiation and function is apparently controlled by Wnt signaling. This review summarizes the most important results obtained in a large number of studies, involving tissue culture experiments, mouse models and human patients. While there are still many open questions regarding the precise molecular interactions controlling Wnt signaling in osteoblasts, it is obvious that understanding this pathway is a key to optimize the therapeutic strategies for treating various skeletal disorders, including osteoporosis.
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Affiliation(s)
- Timur A Yorgan
- Department of Osteology and Biomechanics, University Medical Center Hamburg Eppendorf, Hamburg, 20246 Germany
| | - Thorsten Schinke
- Department of Osteology and Biomechanics, University Medical Center Hamburg Eppendorf, Hamburg, 20246 Germany
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20
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Abstract
The Wnt signaling pathway is long known to play fundamental roles in various aspects of embryonic development, but also in several homeostatic processes controlling tissue functions in adults. The complexity of this system is best underscored by the fact that the mammalian genome encodes for 19 different Wnt ligands, most but not all of them acting through an intracellular stabilization of β-catenin, representing the key molecule within the so-called canonical Wnt signaling pathway. Wnt ligands primarily bind to 10 different serpentine receptors of the Fzd family, and this binding can be positively or negatively regulated by additional molecules present at the surface of the respective target cells. One of these molecules is the transmembrane protein Lrp5, which has been shown to act as a Wnt co-receptor. In 2001, Lrp5, and thereby Wnt signaling, entered center stage in the research area of bone remodeling, a homeostatic process controlling bone mass, whose disturbance causes osteoporosis, one of the most prevalent disorders worldwide. More specifically, it was found that inactivating mutations of the human LRP5 gene cause osteoporosis-pseudoglioma syndrome, a rare genetic disorder characterized by impaired bone formation and persistence of hyaloid vessels in the eyeballs. In addition, activating LRP5 mutations were identified in individuals with osteosclerosis, a high bone mass condition characterized by excessive bone formation. Especially explained by the lack of cost-effective osteoanabolic treatment options, these findings had an immediate impact on the research regarding the bone-forming cell type, i.e. the osteoblast, whose differentiation and function is apparently controlled by Wnt signaling. This review summarizes the most important results obtained in a large number of studies, involving tissue culture experiments, mouse models and human patients. While there are still many open questions regarding the precise molecular interactions controlling Wnt signaling in osteoblasts, it is obvious that understanding this pathway is a key to optimize the therapeutic strategies for treating various skeletal disorders, including osteoporosis.
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Affiliation(s)
- Timur A Yorgan
- Department of Osteology and Biomechanics, University Medical Center Hamburg Eppendorf, Hamburg, 20246 Germany
| | - Thorsten Schinke
- Department of Osteology and Biomechanics, University Medical Center Hamburg Eppendorf, Hamburg, 20246 Germany
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21
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Rendenbach C, Yorgan TA, Heckt T, Otto B, Baldauf C, Jeschke A, Streichert T, David JP, Amling M, Schinke T. Effects of extracellular phosphate on gene expression in murine osteoblasts. Calcif Tissue Int 2014; 94:474-83. [PMID: 24366459 DOI: 10.1007/s00223-013-9831-6] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/12/2013] [Accepted: 12/01/2013] [Indexed: 02/07/2023]
Abstract
That phosphate homeostasis is tightly linked to skeletal mineralization is probably best underscored by the fact that the phosphaturic hormone FGF23 is primarily expressed by terminally differentiated osteoblasts/osteocytes and that increased circulating FGF23 levels are causative for different types of hypophosphatemic rickets. In contrast, FGF23 inactivation results in hyperphosphatemia, and unexpectedly this phenotype is associated with severe osteomalacia in Fgf23-deficient mice. In this context it is interesting that different cell types have been shown to respond to extracellular phosphate, thereby raising the concept that phosphate can act as a signaling molecule. To identify phosphate-responsive genes in primary murine osteoblasts we performed genome wide expression analysis with cells maintained in medium containing either 1 or 4 mM sodium phosphate for 6 h. As confirmed by qRT-PCR, this analysis revealed that several known osteoblast differentiation markers (Bglap, Ibsp, and Phex) were unaffected by raising extracellular phosphate levels. In contrast, we found that the expression of Enpp1 and Ank, two genes encoding inhibitors of matrix mineralization, was induced by extracellular phosphate, while the expression of Sost and Dkk1, two genes encoding inhibitors of bone formation, was negatively regulated. The ability of osteoblasts to respond to extracellular phosphate was dependent on their differentiation state, and shRNA-dependent repression of the phosphate transporter Slc20a1 in MC3T3-E1 cells partially abolished their molecular response to phosphate. Taken together, our results provide further evidence for a role of extracellular phosphate as a signaling molecule and raise the possibility that severe hyperphosphatemia can negatively affect skeletal mineralization.
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Affiliation(s)
- C Rendenbach
- Department of Osteology and Biomechanics, University Medical Center Hamburg Eppendorf, 20246, Hamburg, Germany
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Bartelt A, Beil FT, Müller B, Koehne T, Yorgan TA, Heine M, Yilmaz T, Rüther W, Heeren J, Schinke T, Niemeier A. Hepatic lipase is expressed by osteoblasts and modulates bone remodeling in obesity. Bone 2014; 62:90-8. [PMID: 24440515 DOI: 10.1016/j.bone.2014.01.001] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/26/2013] [Revised: 12/18/2013] [Accepted: 01/07/2014] [Indexed: 01/23/2023]
Abstract
A number of unexpected molecules were recently identified as products of osteoblasts, linking bone homeostasis to systemic energy metabolism. Here we identify the lipolytic enzyme hepatic lipase (HL, encoded by Lipc) as a novel cell-autonomous regulator of osteoblast function. In an unbiased genome-wide expression analysis, we find Lipc to be highly induced upon osteoblast differentiation, verified by quantitative Taqman analyses of primary osteoblasts in vitro and of bone samples in vivo. Functionally, loss of HL in vitro leads to increased expression and secretion of osteoprotegerin (OPG), while expression of some osteoblast differentiation makers is impaired. When challenging energy metabolism in a diet-induced obesity (DIO) study, lack of HL leads to a significant increase in bone formation markers and a decrease in bone resorption markers. Accordingly, in the DIO setting, we observe in Lipc(-/-) animals but not in wild-type controls a significant increase in lumbar vertebral trabecular bone mass and formation rate as well as in femoral trabecular bone mass and cortical thickness. Taken together, we demonstrate that HL expressed by osteoblasts has an impact on osteoblast OPG expression and that lack of HL leads to increased bone mass in DIO. These data provide a novel and completely unexpected molecular link in the complex interplay of osteoblasts and systemic energy metabolism.
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Affiliation(s)
- Alexander Bartelt
- Department of Orthopaedics, University Medical Center Hamburg-Eppendorf, Martinistr. 52, 20246 Hamburg, Germany; Department of Biochemistry and Molecular Cell Biology, University Medical Center Hamburg-Eppendorf, Martinistr. 52, 20246 Hamburg, Germany.
| | - F Timo Beil
- Department of Orthopaedics, University Medical Center Hamburg-Eppendorf, Martinistr. 52, 20246 Hamburg, Germany; Department of Osteology and Biomechanics, University Medical Center Hamburg-Eppendorf, Martinistr. 52, 20246 Hamburg, Germany.
| | - Brigitte Müller
- Department of Orthopaedics, University Medical Center Hamburg-Eppendorf, Martinistr. 52, 20246 Hamburg, Germany; Department of Biochemistry and Molecular Cell Biology, University Medical Center Hamburg-Eppendorf, Martinistr. 52, 20246 Hamburg, Germany.
| | - Till Koehne
- Department of Osteology and Biomechanics, University Medical Center Hamburg-Eppendorf, Martinistr. 52, 20246 Hamburg, Germany.
| | - Timur A Yorgan
- Department of Osteology and Biomechanics, University Medical Center Hamburg-Eppendorf, Martinistr. 52, 20246 Hamburg, Germany.
| | - Markus Heine
- Department of Biochemistry and Molecular Cell Biology, University Medical Center Hamburg-Eppendorf, Martinistr. 52, 20246 Hamburg, Germany.
| | - Tayfun Yilmaz
- Department of Osteology and Biomechanics, University Medical Center Hamburg-Eppendorf, Martinistr. 52, 20246 Hamburg, Germany.
| | - Wolfgang Rüther
- Department of Orthopaedics, University Medical Center Hamburg-Eppendorf, Martinistr. 52, 20246 Hamburg, Germany.
| | - Joerg Heeren
- Department of Biochemistry and Molecular Cell Biology, University Medical Center Hamburg-Eppendorf, Martinistr. 52, 20246 Hamburg, Germany.
| | - Thorsten Schinke
- Department of Osteology and Biomechanics, University Medical Center Hamburg-Eppendorf, Martinistr. 52, 20246 Hamburg, Germany.
| | - Andreas Niemeier
- Department of Orthopaedics, University Medical Center Hamburg-Eppendorf, Martinistr. 52, 20246 Hamburg, Germany; Department of Biochemistry and Molecular Cell Biology, University Medical Center Hamburg-Eppendorf, Martinistr. 52, 20246 Hamburg, Germany.
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