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Bosman A, Appelman-Dijkstra NM, Boot AM, de Borst MH, van de Ven AC, de Jongh RT, Bökenkamp A, van den Bergh JP, van der Eerden BCJ, Zillikens MC. Disease Manifestations and Complications in Dutch X-Linked Hypophosphatemia Patients. Calcif Tissue Int 2024; 114:255-266. [PMID: 38226986 PMCID: PMC10901935 DOI: 10.1007/s00223-023-01172-2] [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: 09/12/2023] [Accepted: 11/27/2023] [Indexed: 01/17/2024]
Abstract
X-linked hypophosphatemia (XLH) is the most common monogenetic cause of chronic hypophosphatemia, characterized by rickets and osteomalacia. Disease manifestations and treatment of XLH patients in the Netherlands are currently unknown. Characteristics of XLH patients participating in the Dutch observational registry for genetic hypophosphatemia and acquired renal phosphate wasting were analyzed. Eighty XLH patients, including 29 children, were included. Genetic testing, performed in 78.8% of patients, showed a PHEX mutation in 96.8%. Median (range) Z-score for height was - 2.5 (- 5.5; 1.0) in adults and - 1.4 (- 3.7; 1.0) in children. Many patients were overweight or obese: 64.3% of adults and 37.0% of children. All children received XLH-related medication e.g., active vitamin D, phosphate supplementation or burosumab, while 8 adults used no medication. Lower age at start of XLH-related treatment was associated with higher height at inclusion. Hearing loss was reported in 6.9% of children and 31.4% of adults. Knee deformities were observed in 75.0% of all patients and osteoarthritis in 51.0% of adult patients. Nephrocalcinosis was observed in 62.1% of children and 33.3% of adults. Earlier start of XLH-related treatment was associated with higher risk of nephrocalcinosis and detection at younger age. Hyperparathyroidism longer than six months was reported in 37.9% of children and 35.3% of adults. This nationwide study confirms the high prevalence of adiposity, hearing loss, bone deformities, osteoarthritis, nephrocalcinosis and hyperparathyroidism in Dutch XLH patients. Early start of XLH-related treatment appears to be beneficial for longitudinal growth but may increase development of nephrocalcinosis.
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Affiliation(s)
- A Bosman
- Department of Internal Medicine, Erasmus MC, University Medical Center Rotterdam, PO Box 2040, 3000, CA, Rotterdam, The Netherlands
| | - N M Appelman-Dijkstra
- Department of Internal Medicine, Leiden University Medical Center, Leiden, The Netherlands
| | - A M Boot
- Department of Pediatrics, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands
| | - M H de Borst
- Department of Internal Medicine, University Medical Center Groningen, Groningen, The Netherlands
| | - A C van de Ven
- Department of Internal Medicine, Radboud University Medical Center, Nijmegen, The Netherlands
| | - R T de Jongh
- Department of Internal Medicine, Amsterdam University Medical Center, Vrije Universiteit, Amsterdam, The Netherlands
| | - A Bökenkamp
- Department of Pediatric Nephrology, Amsterdam University Medical Center, Emma Children's Hospital, Amsterdam, The Netherlands
| | - J P van den Bergh
- Department of Internal Medicine, VieCuri Medical Center, Venlo, The Netherlands
| | - B C J van der Eerden
- Department of Internal Medicine, Erasmus MC, University Medical Center Rotterdam, PO Box 2040, 3000, CA, Rotterdam, The Netherlands
| | - M C Zillikens
- Department of Internal Medicine, Erasmus MC, University Medical Center Rotterdam, PO Box 2040, 3000, CA, Rotterdam, The Netherlands.
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Li J, Nie J, Zhou Z, Guo M, Yang Q, Yuan D, Huang J, Li R, Li Q. Changes of FGF23 and hearing in chronic renal failure and their correlation analysis. Cytokine 2024; 174:156478. [PMID: 38134554 DOI: 10.1016/j.cyto.2023.156478] [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] [Subscribe] [Scholar Register] [Received: 09/14/2023] [Revised: 12/01/2023] [Accepted: 12/12/2023] [Indexed: 12/24/2023]
Abstract
BACKGROUND To explore the association between fibroblast growth factor 23 (FGF23) and hearing in chronic renal failure (CRF). METHODS Pure tone audiometry was used to detect the hearing of patients with CRF; the level of serum FGF23, creatinine, blood urea nitrogen (BUN), parathyroid hormone (PTH), and mean binaural hearing threshold were compared to the control group (people without kidney disease). The rat model of renal failure was established by 5/6 nephrectomy, and the auditory brainstem response (ABR) of rats after modeling was detected by the Tucker Davis Technologies (TDT) system; the expression level of FGF23 in the peripheral blood, renal and cochlear tissue was also detected. RESULTS The incidence of hearing loss (HL) and serum FGF23 were higher in CRF patients than the control group; the sFGF23 was positively correlated with the mean binaural hearing threshold. Animal studies showed that the ABR threshold, creatinine, FGF23, BUN, and PTH increased after modeling; although, an increase in FGF23 was observed earlier than other indicators. The HL of rats with renal failure was significantly correlated with BUN, phosphate, PTH, sFGF23, kFGF23/β-actin, eFGF23/β-actin, weight, and modeling cycle. CONCLUSIONS Both CRF patients and rat models showed high-frequency HL. FGF23 was highly expressed in the serum of HL renal failure patients and rats, as well as in the renal tissue and cochlea of renal failure rats. Therefore, FGF23 may be involved in the occurrence and development of HL caused by CRF.
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Affiliation(s)
- Jiaqing Li
- Department of Nephrology, The First Affiliated Hospital of Kunming Medical University, Kunming, China
| | - Jingwen Nie
- Department of Nephrology, The First Affiliated Hospital of Kunming Medical University, Kunming, China
| | - Zhu Zhou
- Department of Nephrology, The First Affiliated Hospital of Kunming Medical University, Kunming, China
| | - Min Guo
- Department of Otolaryngology, The First Affiliated Hospital of Kunming Medical University, Kunming, China
| | - Qing Yang
- Department of Nephrology, The First Affiliated Hospital of Kunming Medical University, Kunming, China
| | - Dunlu Yuan
- Department of Nephrology, The First Affiliated Hospital of Kunming Medical University, Kunming, China
| | - Jingjing Huang
- Department of Medical Record, The Third People's Hospital of Kunming, Kunming, China
| | - Ruomei Li
- Department of Otolaryngology, The First Affiliated Hospital of Kunming Medical University, Kunming, China
| | - Qing Li
- Department of Nephrology, The First Affiliated Hospital of Kunming Medical University, Kunming, China.
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Delsmann MM, Bonik P, Ocokoljic A, Häussler SM, Püschel K, Praetorius M, Amling M, Peichl J, Rolvien T. Cholesteatoma Severely Impacts the Integrity and Bone Material Quality of the Incus. Calcif Tissue Int 2023; 113:609-617. [PMID: 37872266 PMCID: PMC10673740 DOI: 10.1007/s00223-023-01144-6] [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: 09/13/2023] [Accepted: 09/18/2023] [Indexed: 10/25/2023]
Abstract
Cholesteatoma can lead to progressive destruction of the auditory ossicles along with conductive hearing loss but precise data on the microstructural, cellular, and compositional aspects of affected ossicles are not available. Here, we obtained incus specimens from patients who had cholesteatoma with conductive hearing loss. Incudes were evaluated by micro-computed tomography, histomorphometry on undecalcified sections, quantitative backscattered electron imaging, and nanoindentation. Results were compared with two control groups taken from patients with chronic otitis media as well as from skeletally intact donors at autopsy. The porosity of incus specimens was higher in cholesteatoma than in chronic otitis media, along with a higher osteoclast surface per bone surface. Histomorphometric assessment revealed higher osteoid levels and osteocyte numbers in cholesteatoma incudes. Incudes affected by cholesteatoma also showed lower matrix mineralization compared with specimens from healthy controls and chronic otitis media. Furthermore, the modulus-to-hardness ratio was higher in cholesteatoma specimens compared with controls. Taken together, we demonstrated increased porosity along with increased osteoclast indices, impaired matrix mineralization, and altered biomechanical properties as distinct features of the incus in cholesteatoma. Based on our findings, a possible impact of impaired bone quality on conductive hearing loss should be further explored.
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Affiliation(s)
- Maximilian M Delsmann
- Division of Orthopaedics, Department of Trauma and Orthopaedic Surgery, University Medical Center Hamburg-Eppendorf, Martinistraße 52, 20246, Hamburg, Germany
- Department of Osteology and Biomechanics, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Paul Bonik
- Division of Orthopaedics, Department of Trauma and Orthopaedic Surgery, University Medical Center Hamburg-Eppendorf, Martinistraße 52, 20246, Hamburg, Germany
| | - Ana Ocokoljic
- Division of Orthopaedics, Department of Trauma and Orthopaedic Surgery, University Medical Center Hamburg-Eppendorf, Martinistraße 52, 20246, Hamburg, Germany
| | - Sophia M Häussler
- Department of Otorhinolaryngology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Klaus Püschel
- Department of Legal Medicine, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Mark Praetorius
- Department of Otorhinolaryngology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Michael Amling
- Department of Osteology and Biomechanics, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Jonathan Peichl
- Department of Otorhinolaryngology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Tim Rolvien
- Division of Orthopaedics, Department of Trauma and Orthopaedic Surgery, University Medical Center Hamburg-Eppendorf, Martinistraße 52, 20246, Hamburg, Germany.
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Seefried L, Duplan MB, Briot K, Collins MT, Evans R, Florenzano P, Hawkins N, Javaid MK, Lachmann R, Ward LM. Anticipated effects of burosumab treatment on long-term clinical sequelae in XLH: expert perspectives. Front Endocrinol (Lausanne) 2023; 14:1211426. [PMID: 37547321 PMCID: PMC10400326 DOI: 10.3389/fendo.2023.1211426] [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] [Grants] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/24/2023] [Accepted: 06/27/2023] [Indexed: 08/08/2023] Open
Abstract
X-linked hypophosphatemia (XLH) is a rare, progressive, genetic disease with multisystem impact that typically begins to manifest in early childhood. Two treatment options exist: oral phosphate in combination with active vitamin D ("conventional therapy") and a fully human monoclonal anti-FGF23 antibody, burosumab. The clinical benefit of conventional therapy in adults is limited, and poor tolerance and complications are common. Burosumab was first approved as a treatment for XLH in 2018 and its disease-modifying benefits in clinical trials in children suggest burosumab treatment could also alter the disease course in adults. Without long-term clinical data on multiple XLH-related sequelae available, the results of an elicitation exercise are reported, in which eight global experts in XLH posited how long-term treatment with burosumab is anticipated to impact the life course of clinical sequelae in adults with XLH. Based on their clinical experiences, the available evidence and their disease understanding, the experts agreed that some long-term benefits of using burosumab are likely in adults with XLH even if they have a misaligned skeleton from childhood. Burosumab treatment is anticipated to reduce the incidence of fractures and halt the progression of clinical sequelae associated with conventional therapy. While the trajectories for established dental abscesses are not expected to improve with burosumab treatment, dental abscess development may be prevented. Starting treatment with burosumab in childhood to increase the likelihood of an aligned skeleton and continuation into and throughout adulthood to maintain euphosphatemia may optimize patient outcomes, although future real-world investigation is required to support this hypothesis.
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Affiliation(s)
- Lothar Seefried
- Orthopedic Department, University of Würzburg, Würzburg, Germany
| | - Martin Biosse Duplan
- Service de Médecine Bucco-Dentaire, Hôpital Bretonneau, AP-HP, Paris, France
- UFR d’Odontologie, Université de Paris, Paris, France
- Institut Imagine, INSERM, Paris, France
| | - Karine Briot
- Department of Rheumatology, Hôpital Cochin, Université de Paris-Cité, Paris, France
| | - Michael T. Collins
- Skeletal Disorders and Mineral Homeostasis Section, National Institutes of Dental and Craniofacial Research, National Institutes of Health, Bethesda, MD, United States
| | - Rachel Evans
- Health Economics, Visible Analytics, Oxford, United Kingdom
| | - Pablo Florenzano
- Department of Endocrinology, Pontificia Universidad Católica de Chile, Santiago, Chile
- Department of Endocrinology, Centro Traslacional en Endocrinologia (CETREN-UC), Santiago, Chile
| | - Neil Hawkins
- Health Economics, Visible Analytics, Oxford, United Kingdom
| | - Muhammad Kassim Javaid
- Nuffield Department of Orthopaedics, Rheumatology and Musculoskeletal Sciences, University of Oxford, Oxford, United Kingdom
| | - Robin Lachmann
- Charles Dent Metabolic Unit, National Hospital for Neurology and Neurosurgery, London, United Kingdom
| | - Leanne M. Ward
- Children’s Hospital of Eastern Ontario, University of Ottawa, Ottawa, ON, Canada
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Delsmann J, Schmidt B, Oheim R, Amling M, Rolvien T, Siebert U. Bone mineral density and microarchitecture change during skeletal growth in harbor seals (Phoca vitulina) from the German coast. Sci Rep 2023; 13:7196. [PMID: 37137898 PMCID: PMC10156659 DOI: 10.1038/s41598-023-33911-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2023] [Accepted: 04/20/2023] [Indexed: 05/05/2023] Open
Abstract
Across species, the skeletal system shares mutual functions, including the protection of inner organs, structural basis for locomotion, and acting as an endocrine organ, thus being of pivotal importance for survival. However, insights into skeletal characteristics of marine mammals are limited, especially in the growing skeleton. Harbor seals (Phoca vitulina) are common marine mammals in the North and Baltic Seas and are suitable indicators of the condition of their ecosystem. Here, we analyzed whole-body areal bone mineral density (aBMD) by dual-energy X-ray absorptiometry (DXA) and lumbar vertebrae by high-resolution peripheral quantitative computed tomography (HR-pQCT) in neonate, juvenile, and adult harbor seals. Along skeletal growth, an increase in two-dimensional aBMD by DXA was paralleled by three-dimensional volumetric BMD by HR-pQCT, which could be attributed to an increasing trabecular thickness while trabecular number remained constant. Strong associations were observed between body dimensions (weight and length) and aBMD and trabecular microarchitecture (R2 = 0.71-0.92, all p < 0.001). To validate the results of the DXA measurement (i.e., the standard method used worldwide to diagnose osteoporosis in humans), we performed linear regression analyses with the three-dimensional measurements from the HR-pQCT method, which revealed strong associations between the two imaging techniques (e.g., aBMD and Tb.Th: R2 = 0.96, p < 0.0001). Taken together, our findings highlight the importance of systematic skeletal investigations in marine mammals during growth, illustrating the high accuracy of DXA in this context. Regardless of the limited sample size, the observed trabecular thickening is likely to represent a distinct pattern of vertebral bone maturation. As differences in nutritional status, among other factors, are likely to affect skeletal health, it appears essential to routinely perform skeletal assessments in marine mammals. Placing the results in the context of environmental exposures may allow effective measures to protect their populations.
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Affiliation(s)
- Julian Delsmann
- Department of Osteology and Biomechanics, University Medical Center Hamburg-Eppendorf, Lottestr. 59, 22529, Hamburg, Germany
- Division of Orthopedics, Department of Trauma and Orthopedic Surgery, University Medical Center Hamburg-Eppendorf, Martinistr. 52, 20246, Hamburg, Germany
| | - Britta Schmidt
- Institute for Terrestrial and Aquatic Wildlife Research, University of Veterinary Medicine Hannover, Foundation, Werftstr. 6, 25746, Büsum, Germany
| | - Ralf Oheim
- Department of Osteology and Biomechanics, University Medical Center Hamburg-Eppendorf, Lottestr. 59, 22529, Hamburg, Germany
| | - Michael Amling
- Department of Osteology and Biomechanics, University Medical Center Hamburg-Eppendorf, Lottestr. 59, 22529, Hamburg, Germany
| | - Tim Rolvien
- Division of Orthopedics, Department of Trauma and Orthopedic Surgery, University Medical Center Hamburg-Eppendorf, Martinistr. 52, 20246, Hamburg, Germany
| | - Ursula Siebert
- Institute for Terrestrial and Aquatic Wildlife Research, University of Veterinary Medicine Hannover, Foundation, Werftstr. 6, 25746, Büsum, Germany.
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Wackym PA, Balaban CD, Van Osch OJ, Morris BT, Tamakloe MA, Salvatore VL, Duwadi S, Gay JD, Mowery TM. New model of superior semicircular canal dehiscence with reversible diagnostic findings characteristic of patients with the disorder. Front Neurol 2023; 13:1035478. [PMID: 36742050 PMCID: PMC9892720 DOI: 10.3389/fneur.2022.1035478] [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: 09/02/2022] [Accepted: 11/15/2022] [Indexed: 01/20/2023] Open
Abstract
Background Third window syndrome is a vestibular-cochlear disorder in humans in which a third mobile window of the otic capsule creates changes to the flow of sound pressure energy through the perilymph/endolymph. The nature and location of this third mobile window can occur at many different sites (or multiple sites); however, the most common third mobile window is superior semicircular canal dehiscence (SSCD). There are two essential objective diagnostic characteristics needed to validate a model of SSCD: the creation of a pseudoconductive hearing loss and cVEMP increased amplitude and decreased threshold. Methods Adult Mongolian gerbils (n = 36) received surgical fenestration of the superior semicircular canal of the left inner ear. ABR and c+VEMP testing were carried out prior to surgery and over acute (small 1 mm SSCD, 1-10 days) or prolonged (large 2 mm SSCD, 28 days) recovery. Because recovery of function occurred quickly, condenser brightfield stereomicroscopic examination of the dehiscence site was carried out for the small SSCD animals post-hoc and compared to both ABRs and c+VEMPs. Micro-CT analysis was also completed with representative samples of control, day 3 and 10 post-SSCD animals. Results The SSCD created a significant worsening of hearing thresholds of the left ear; especially in the lower frequency domain (1-4 kHz). Left (EXP)/right (CTL) ear comparisons via ABR show significant worsening thresholds at the same frequency representations, which is a proxy for the human pseudoconductive hearing loss seen in SSCD. For the c+VEMP measurements, increased amplitude of the sound-induced response (N1 2.5 ms and P1 3.2 ms) was observed in animals that received larger fenestrations. As the bone regrew, the c+VEMP and ABR responses returned toward preoperative values. For small SSCD animals, micro-CT data show that progressive osteoneogenesis results in resurfacing of the SSCD without bony obliteration. Conclusion The large (2 mm) SSCD used in our gerbil model results in similar electrophysiologic findings observed in patients with SSCD. The changes observed also reverse and return to baseline as the SSCD heals by bone resurfacing (with the lumen intact). Hence, this model does not require a second surgical procedure to plug the SSCD.
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Affiliation(s)
- P. Ashley Wackym
- Department of Otolaryngology – Head and Neck Surgery, Rutgers Robert Wood Johnson Medical School, New Brunswick, NJ, United States,Rutgers Brain Health Institute, New Brunswick, NJ, United States
| | - Carey D. Balaban
- Departments of Otolaryngology, Neurobiology, Communication Sciences and Disorders, Bioengineering and Mechanical Engineering and Materials Science, University of Pittsburgh School of Medicine, Pittsburgh, PA, United States
| | - Olivia J. Van Osch
- Department of Otolaryngology – Head and Neck Surgery, Rutgers Robert Wood Johnson Medical School, New Brunswick, NJ, United States
| | - Brian T. Morris
- Department of Otolaryngology – Head and Neck Surgery, Rutgers Robert Wood Johnson Medical School, New Brunswick, NJ, United States
| | - Mark-Avery Tamakloe
- Department of Otolaryngology – Head and Neck Surgery, Rutgers Robert Wood Johnson Medical School, New Brunswick, NJ, United States
| | - Victoria L. Salvatore
- Department of Otolaryngology – Head and Neck Surgery, Rutgers Robert Wood Johnson Medical School, New Brunswick, NJ, United States
| | - Sudan Duwadi
- Department of Otolaryngology – Head and Neck Surgery, Rutgers Robert Wood Johnson Medical School, New Brunswick, NJ, United States
| | - Jennifer D. Gay
- Department of Otolaryngology – Head and Neck Surgery, Rutgers Robert Wood Johnson Medical School, New Brunswick, NJ, United States
| | - Todd M. Mowery
- Department of Otolaryngology – Head and Neck Surgery, Rutgers Robert Wood Johnson Medical School, New Brunswick, NJ, United States,Rutgers Brain Health Institute, New Brunswick, NJ, United States,*Correspondence: Todd M. Mowery ✉
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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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