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Green AJ, Wall AR, Weeks RD, Mattingly CJ, Marsden KC, Planchart A. Developmental cadmium exposure disrupts zebrafish vestibular calcium channels interfering with otolith formation and inner ear function. Neurotoxicology 2023; 96:129-139. [PMID: 37060951 PMCID: PMC10518193 DOI: 10.1016/j.neuro.2023.04.006] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2022] [Revised: 04/11/2023] [Accepted: 04/12/2023] [Indexed: 04/17/2023]
Abstract
Dizziness or balance problems are estimated to affect approximately 3.3 million children aged three to 17 years. These disorders develop from a breakdown in the balance control system and can be caused by anything that affects the inner ear or the brain, including exposure to environmental toxicants. One potential environmental toxicant linked to balance disorders is cadmium, an extremely toxic metal that occurs naturally in the earth's crust and is released as a byproduct of industrial processes. Cadmium is associated with balance and vestibular dysfunction in adults exposed occupationally, but little is known about the developmental effects of low-concentration cadmium exposure. Our findings indicate that zebrafish exposed to 10-60 parts per billion (ppb) cadmium from four hours post-fertilization (hpf) to seven days post-fertilization (dpf) exhibit abnormal behaviors, including pronounced increases in auditory sensitivity and circling behavior, both of which are linked to reductions in otolith growth and are rescued by the addition of calcium to the media. Pharmacological intervention shows that agonist-induced activation of the P2X calcium ion channel in the presence of cadmium restores otolith size. In conclusion, cadmium-induced ototoxicity is linked to vestibular-based behavioral abnormalities and auditory sensitivity following developmental exposure, and calcium ion channel function is associated with these defects.
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Affiliation(s)
- Adrian J Green
- Department of Biological Sciences, North Carolina State University, Raleigh, NC 27695, USA; Bioinformatics Research Center, North Carolina State University, Raleigh, NC 27695, USA.
| | - Alex R Wall
- Department of Biological Sciences, North Carolina State University, Raleigh, NC 27695, USA
| | - Ryan D Weeks
- Department of Biological Sciences, North Carolina State University, Raleigh, NC 27695, USA
| | - Carolyn J Mattingly
- Department of Biological Sciences, North Carolina State University, Raleigh, NC 27695, USA; Center for Human Health and the Environment, North Carolina State University, Raleigh, NC 27695, USA
| | - Kurt C Marsden
- Department of Biological Sciences, North Carolina State University, Raleigh, NC 27695, USA; Center for Human Health and the Environment, North Carolina State University, Raleigh, NC 27695, USA
| | - Antonio Planchart
- Department of Biological Sciences, North Carolina State University, Raleigh, NC 27695, USA; Center for Human Health and the Environment, North Carolina State University, Raleigh, NC 27695, USA
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2
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Wang Y, Lyu J, Qian X, Chen B, Sun H, Luo W, Chi F, Li H, Ren D. Involvement of Dmp1 in the Precise Regulation of Hair Bundle Formation in the Developing Cochlea. BIOLOGY 2023; 12:biology12040625. [PMID: 37106825 PMCID: PMC10135853 DOI: 10.3390/biology12040625] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/11/2023] [Revised: 04/02/2023] [Accepted: 04/07/2023] [Indexed: 04/29/2023]
Abstract
Dentin matrix protein 1 (Dmp1) is a highly phosphorylated, extracellular matrix protein that is extensively expressed in bone and teeth but also found in soft tissues, including brain and muscle. However, the functions of Dmp1 in the mice cochlea are unknown. Our study showed that Dmp1 was expressed in auditory hair cells (HCs), with the role of Dmp1 in those cells identified using Dmp1 cKD mice. Immunostaining and scanning electron microscopy of the cochlea at P1 revealed that Dmp1 deficiency in mice resulted in an abnormal stereociliary bundle morphology and the mispositioning of the kinocilium. The following experiments further demonstrated that the cell-intrinsic polarity of HCs was affected without apparent effect on the tissue planer polarity, based on the observation that the asymmetric distribution of Vangl2 was unchanged whereas the Gαi3 expression domain was enlarged and Par6b expression was slightly altered. Then, the possible molecular mechanisms of Dmp1 involvement in inner ear development were explored via RNA-seq analysis. The study suggested that the Fgf23-Klotho endocrine axis may play a novel role in the inner ear and Dmp1 may regulate the kinocilium-stereocilia interaction via Fgf23-Klotho signaling. Together, our results proved the critical role of Dmp1 in the precise regulation of hair bundle morphogenesis in the early development of HCs.
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Affiliation(s)
- Yanmei Wang
- ENT Institute and Department of Otorhinolaryngology, Eye & ENT Hospital, Fudan University, Shanghai 200031, China
- NHC Key Laboratory of Hearing Medicine, Fudan University, Shanghai 200031, China
| | - Jihan Lyu
- ENT Institute and Department of Otorhinolaryngology, Eye & ENT Hospital, Fudan University, Shanghai 200031, China
- NHC Key Laboratory of Hearing Medicine, Fudan University, Shanghai 200031, China
| | - Xiaoqing Qian
- ENT Institute and Department of Otorhinolaryngology, Eye & ENT Hospital, Fudan University, Shanghai 200031, China
- NHC Key Laboratory of Hearing Medicine, Fudan University, Shanghai 200031, China
| | - Binjun Chen
- ENT Institute and Department of Otorhinolaryngology, Eye & ENT Hospital, Fudan University, Shanghai 200031, China
- NHC Key Laboratory of Hearing Medicine, Fudan University, Shanghai 200031, China
| | - Haojie Sun
- ENT Institute and Department of Otorhinolaryngology, Eye & ENT Hospital, Fudan University, Shanghai 200031, China
- NHC Key Laboratory of Hearing Medicine, Fudan University, Shanghai 200031, China
| | - Wenwei Luo
- Department of Otolaryngology-Head and Neck Surgery, Guangdong Provincial People's Hospital, Guangdong Academy of Medical Sciences, Guangzhou 510080, China
- The Second School of Clinical Medicine, South Medical University, Guangzhou 510080, China
| | - Fanglu Chi
- ENT Institute and Department of Otorhinolaryngology, Eye & ENT Hospital, Fudan University, Shanghai 200031, China
- NHC Key Laboratory of Hearing Medicine, Fudan University, Shanghai 200031, China
| | - Hongzhe Li
- Research Service, VA Loma Linda Healthcare System, Loma Linda, CA 92350, USA
- Department of Otolaryngology-Head and Neck Surgery, Loma Linda University School of Medicine, Loma Linda, CA 92350, USA
| | - Dongdong Ren
- ENT Institute and Department of Otorhinolaryngology, Eye & ENT Hospital, Fudan University, Shanghai 200031, China
- NHC Key Laboratory of Hearing Medicine, Fudan University, Shanghai 200031, China
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3
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Mackowetzky K, Dicipulo R, Fox SC, Philibert DA, Todesco H, Doshi JD, Kawakami K, Tierney K, Waskiewicz AJ. Retinoic acid signaling regulates late stages of semicircular canal morphogenesis and otolith maintenance in the zebrafish inner ear. Dev Dyn 2022; 251:1798-1815. [PMID: 35710880 DOI: 10.1002/dvdy.510] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2021] [Revised: 03/09/2022] [Accepted: 03/10/2022] [Indexed: 11/08/2022] Open
Abstract
BACKGROUND The vitamin A derivative all-trans retinoic acid (RA) regulates early stages of inner ear development. As the early disruption of the RA pathway results in profound mispatterning of the developing inner ear, this confounds analyses of specific roles in later stages. Therefore, we used the temporal-specific exposure of all-trans RA or diethylaminobenzaldehyde to evaluate RA functions in late otic development. RESULTS Perturbing late RA signaling causes behavioral defects analogous to those expected in larvae suffering from vestibular dysfunction. These larvae also demonstrate malformations of the semi-circular canals, as visualized through (a) use of the transgenic strain nkhspdmc12a, a fluorescent reporter expressed in otic epithelium; and (b) injection of the fluorescent lipophilic dye DiI. We also noted the altered expression of genes encoding ECM proteins or modifying enzymes. Other malformations of the inner ear observed in our work include the loss or reduced size of the utricular and saccular otoliths, suggesting a role for RA in otolith maintenance. CONCLUSION Our work has identified a previously undescribed late phase of RA activity in otic development, demonstrating that vestibular defects observed in human patients in relation to perturbed RA signaling are not solely due to its early disruption in otic development.
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Affiliation(s)
- Kacey Mackowetzky
- Department of Biological Sciences, University of Alberta, Edmonton, Alberta, Canada
| | - Renée Dicipulo
- Department of Biological Sciences, University of Alberta, Edmonton, Alberta, Canada
| | - Sabrina C Fox
- Department of Biological Sciences, University of Alberta, Edmonton, Alberta, Canada.,Women & Children's Health Research Institute, Edmonton, Alberta, Canada
| | - Danielle A Philibert
- Department of Biological Sciences, University of Alberta, Edmonton, Alberta, Canada
| | - Hayley Todesco
- Department of Biological Sciences, University of Alberta, Edmonton, Alberta, Canada
| | - Jainil D Doshi
- Department of Biological Sciences, University of Alberta, Edmonton, Alberta, Canada
| | - Koichi Kawakami
- Laboratory of Molecular and Developmental Biology, National Institute of Genetics, Shizuoka, Japan
| | - Keith Tierney
- Department of Biological Sciences, University of Alberta, Edmonton, Alberta, Canada.,School of Public Health, University of Alberta, Edmonton, Alberta, Canada
| | - Andrew J Waskiewicz
- Department of Biological Sciences, University of Alberta, Edmonton, Alberta, Canada.,Women & Children's Health Research Institute, Edmonton, Alberta, Canada
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4
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Porębska A, Różycka M, Hołubowicz R, Szewczuk Z, Ożyhar A, Dobryszycki P. Functional derivatives of human dentin matrix protein 1 modulate morphology of calcium carbonate crystals. FASEB J 2020; 34:6147-6165. [PMID: 32190922 DOI: 10.1096/fj.201901999r] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2019] [Revised: 02/07/2020] [Accepted: 02/21/2020] [Indexed: 12/23/2022]
Abstract
Dentin matrix protein 1 (DMP1) is an acidic, extracellular matrix protein essential for biomineralization of calcium phosphate, in bone and dentin. It is proteolytically processed into two fragments, 44K and 56K. Recently, the presence of DMP1 was noticed in inner ear, specifically in otoconia, which are calcium carbonate biominerals involved in sensing of balance. In this study, the solution structure and biomineralization activity of otoconial 44K and 56K fragments toward calcium carbonate were investigated. The results of analytical ultracentrifugation, circular dichroism, and gel filtration indicated that DMP1 fragments are disordered in solution. Notably, 56K formed oligomers in the presence of calcium ions. It was also observed that both fragments influenced the crystal growth by in vitro biomineralization assay and scanning electron microscopy. In addition, they sequester the calcium ions during the calcite formation. Calcium carbonate crystals precipitated in vitro changed their size and shape in the presence of DMP1 fragments. Oligomerization propensity of 56K may significantly enhance this function. Our study indicates that intrinsically disordered DMP1 has a previously unknown regulatory function for biomineralization of otoconia.
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Affiliation(s)
- Aleksandra Porębska
- Department of Biochemistry, Molecular Biology and Biotechnology, Faculty of Chemistry, Wrocław University of Science and Technology, Wrocław, Poland
| | - Mirosława Różycka
- Department of Biochemistry, Molecular Biology and Biotechnology, Faculty of Chemistry, Wrocław University of Science and Technology, Wrocław, Poland
| | - Rafał Hołubowicz
- Department of Biochemistry, Molecular Biology and Biotechnology, Faculty of Chemistry, Wrocław University of Science and Technology, Wrocław, Poland
| | | | - Andrzej Ożyhar
- Department of Biochemistry, Molecular Biology and Biotechnology, Faculty of Chemistry, Wrocław University of Science and Technology, Wrocław, Poland
| | - Piotr Dobryszycki
- Department of Biochemistry, Molecular Biology and Biotechnology, Faculty of Chemistry, Wrocław University of Science and Technology, Wrocław, Poland
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5
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Liu T, Wang J, Xie X, Wang K, Sui T, Liu D, Lai L, Zhao H, Li Z, Feng JQ. DMP1 Ablation in the Rabbit Results in Mineralization Defects and Abnormalities in Haversian Canal/Osteon Microarchitecture. J Bone Miner Res 2019; 34:1115-1128. [PMID: 30827034 DOI: 10.1002/jbmr.3683] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/24/2018] [Revised: 01/11/2019] [Accepted: 01/19/2019] [Indexed: 02/05/2023]
Abstract
DMP1 (dentin matrix protein 1) is an extracellular matrix protein highly expressed in bones. Studies of Dmp1 knockout (KO) mice led to the discovery of a rare autosomal recessive form of hypophosphatemic rickets (ARHR) caused by DMP1 mutations. However, there are limitations for using this mouse model to study ARHR, including a lack of Haversian canals and osteons (that occurs only in large mammalian bones), high levels of fibroblast growth factor 23 (FGF23), and PTH, in comparison with a moderate elevation of FGF23 and unchanged PTH in human ARHR patients. To better understand this rare disease, we deleted the DMP1 gene in rabbit using CRISPR/Cas9. This rabbit model recapitulated many features of human ARHR, such as the rachitic rosary (expansion of the anterior rib ends at the costochondral junctions), moderately increased FGF23, and normal PTH levels, as well as severe defects in bone mineralization. Unexpectedly, all DMP1 KO rabbits died by postnatal week 8. They developed a severe bone microarchitecture defect: a major increase in the central canal areas of osteons, concurrent with massive accumulation of osteoid throughout all bone matrix (a defect in mineralization), suggesting a new paradigm, where rickets is caused by a combination of a defect in bone microarchitecture and a failure in mineralization. Furthermore, a study of DMP1 KO bones found accelerated chondrogenesis, whereas ARHR has commonly been thought to be involved in reduced chondrogenesis. Our findings with newly developed DMP1 KO rabbits suggest a revised understanding of the mechanism underlying ARHR. © 2019 American Society for Bone and Mineral Research.
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Affiliation(s)
- Tingjun Liu
- Jilin Provincial Key Laboratory of Animal Embryo Engineering, Institute of Zoonosis, Jilin University, Changchun, China
| | - Jun Wang
- Department of Biomedical Sciences, Texas A&M University College of Dentistry, Dallas, TX, USA.,State Key Laboratory of Oral Diseases, National Clinical Research Center for Oral Diseases, Department of Periodontics, West China Hospital of Stomatology, Sichuan University, Chengdu, China
| | - Xudong Xie
- Department of Biomedical Sciences, Texas A&M University College of Dentistry, Dallas, TX, USA.,State Key Laboratory of Oral Diseases, National Clinical Research Center for Oral Diseases, Department of Periodontics, West China Hospital of Stomatology, Sichuan University, Chengdu, China
| | - Ke Wang
- Department of Biomedical Sciences, Texas A&M University College of Dentistry, Dallas, TX, USA
| | - Tingting Sui
- Jilin Provincial Key Laboratory of Animal Embryo Engineering, Institute of Zoonosis, Jilin University, Changchun, China
| | - Di Liu
- Jilin Provincial Key Laboratory of Animal Embryo Engineering, Institute of Zoonosis, Jilin University, Changchun, China
| | - Liangxue Lai
- Key Laboratory of Regenerative Biology, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou, China
| | - Hu Zhao
- Department of Biomedical Sciences, Texas A&M University College of Dentistry, Dallas, TX, USA
| | - Zhanjun Li
- Jilin Provincial Key Laboratory of Animal Embryo Engineering, Institute of Zoonosis, Jilin University, Changchun, China
| | - Jian Q Feng
- Department of Biomedical Sciences, Texas A&M University College of Dentistry, Dallas, TX, USA
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6
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Inner ear ossification and mineralization kinetics in human embryonic development - microtomographic and histomorphological study. Sci Rep 2017; 7:4825. [PMID: 28684743 PMCID: PMC5500530 DOI: 10.1038/s41598-017-05151-0] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2017] [Accepted: 05/24/2017] [Indexed: 12/18/2022] Open
Abstract
Little is known about middle and inner ear development during the second and third parts of human fetal life. Using ultra-high resolution Microcomputed Tomography coupled with bone histology, we performed the first quantitative middle and inner ear ossification/mineralization evaluation of fetuses between 17 and 39 weeks of gestational age. We show distinct ossification paces between ossicles, with a belated development of the stapes. A complete cochlear bony covering is observed within the time-frame of the onset of hearing, whereas distinct time courses of ossification for semicircular canal envelopes are observed in relation to the start of vestibular functions. The study evidences a spatio-temporal relationship between middle and inner ear structure development and the onset of hearing and balance, critical senses for the fetal adaptation to birth.
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7
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Leduc RYM, Rauw G, Baker GB, McDermid HE. What Goes Around Can Come Around: An Unexpected Deleterious Effect of Using Mouse Running Wheels for Environmental Enrichment. JOURNAL OF THE AMERICAN ASSOCIATION FOR LABORATORY ANIMAL SCIENCE : JAALAS 2017; 56:194-201. [PMID: 28315651 PMCID: PMC5361047] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Received: 02/03/2016] [Revised: 07/01/2016] [Accepted: 07/24/2016] [Indexed: 06/06/2023]
Abstract
Environmental enrichment items such as running wheels can promote the wellbeing of laboratory mice. Growing evidence suggests that wheel running simulates exercise effects in many mouse models of human conditions, but this activity also might change other aspects of mouse behavior. In this case study, we show that the presence of running wheels leads to pronounced and permanent circling behavior with route-tracing in a proportion of the male mice of a genetically distinct cohort. The genetic background of this cohort includes a mutation in Arhgap19, but genetic crosses showed that an unknown second-site mutation likely caused the induced circling behavior. Behavioral tests for inner-ear function indicated a normal sense of gravity in the circling mice. However, the levels of dopamine, serotonin, and some dopamine metabolites were lower in the brains of circling male mice than in mice of the same genetic background that were weaned without wheels. Circling was seen in both singly and socially housed male mice. The additional stress of fighting may have exacerbated the predisposition to circling in the socially housed animals. Singly and socially housed male mice without wheels did not circle. Our current findings highlight the importance and possibly confounding nature of the environmental and genetic background in mouse behavioral studies, given that the circling behavior and alterations in dopamine and serotonin levels in this mouse cohort occurred only when the male mice were housed with running wheels.
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Affiliation(s)
- Renee Y M Leduc
- Departments of Biological Sciences, Neurochemical Research Unit, University of Alberta, Edmonton, Alberta, Canada;,
| | - Gail Rauw
- Psychiatry, Neurochemical Research Unit, University of Alberta, Edmonton, Alberta, Canada
| | - Glen B Baker
- Psychiatry, Neurochemical Research Unit, University of Alberta, Edmonton, Alberta, Canada
| | - Heather E McDermid
- Departments of Biological Sciences, Neurochemical Research Unit, University of Alberta, Edmonton, Alberta, Canada
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8
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Lundberg YW, Xu Y, Thiessen KD, Kramer KL. Mechanisms of otoconia and otolith development. Dev Dyn 2014; 244:239-53. [PMID: 25255879 DOI: 10.1002/dvdy.24195] [Citation(s) in RCA: 96] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2014] [Revised: 08/25/2014] [Accepted: 08/26/2014] [Indexed: 01/17/2023] Open
Abstract
BACKGROUND Otoconia are bio-crystals that couple mechanic forces to the sensory hair cells in the utricle and saccule, a process essential for us to sense linear acceleration and gravity for the purpose of maintaining bodily balance. In fish, structurally similar bio-crystals called otoliths mediate both balance and hearing. Otoconia abnormalities are common and can cause vertigo and imbalance in humans. However, the molecular etiology of these illnesses is unknown, as investigators have only begun to identify genes important for otoconia formation in recent years. RESULTS To date, in-depth studies of selected mouse otoconial proteins have been performed, and about 75 zebrafish genes have been identified to be important for otolith development. CONCLUSIONS This review will summarize recent findings as well as compare otoconia and otolith development. It will provide an updated brief review of otoconial proteins along with an overview of the cells and cellular processes involved. While continued efforts are needed to thoroughly understand the molecular mechanisms underlying otoconia and otolith development, it is clear that the process involves a series of temporally and spatially specific events that are tightly coordinated by numerous proteins. Such knowledge will serve as the foundation to uncover the molecular causes of human otoconia-related disorders.
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Affiliation(s)
- Yunxia Wang Lundberg
- Vestibular Genetics Laboratory, Boys Town National Research Hospital, Omaha, Nebraska
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9
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Lundberg YW, Xu Y, Thiessen KD, Kramer KL. Mechanisms of otoconia and otolith development. Dev Dyn 2014. [PMID: 25255879 DOI: 10.1002/dvdy.24195(2014)] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
BACKGROUND Otoconia are bio-crystals that couple mechanic forces to the sensory hair cells in the utricle and saccule, a process essential for us to sense linear acceleration and gravity for the purpose of maintaining bodily balance. In fish, structurally similar bio-crystals called otoliths mediate both balance and hearing. Otoconia abnormalities are common and can cause vertigo and imbalance in humans. However, the molecular etiology of these illnesses is unknown, as investigators have only begun to identify genes important for otoconia formation in recent years. RESULTS To date, in-depth studies of selected mouse otoconial proteins have been performed, and about 75 zebrafish genes have been identified to be important for otolith development. CONCLUSIONS This review will summarize recent findings as well as compare otoconia and otolith development. It will provide an updated brief review of otoconial proteins along with an overview of the cells and cellular processes involved. While continued efforts are needed to thoroughly understand the molecular mechanisms underlying otoconia and otolith development, it is clear that the process involves a series of temporally and spatially specific events that are tightly coordinated by numerous proteins. Such knowledge will serve as the foundation to uncover the molecular causes of human otoconia-related disorders.
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Affiliation(s)
- Yunxia Wang Lundberg
- Vestibular Genetics Laboratory, Boys Town National Research Hospital, Omaha, Nebraska
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10
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Beta-galactosidase staining in the skeleton. METHODS IN MOLECULAR BIOLOGY (CLIFTON, N.J.) 2014; 1130:185-191. [PMID: 24482173 DOI: 10.1007/978-1-62703-989-5_13] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
The lacZ gene, encoding for the β-galactosidase enzyme, is widely used as a reporter gene in bone biology due to the ease of visualization in situ on whole-mount or on tissue sections. In this protocol we provide detailed methods for visualizing this reporter gene for both in vivo and in vitro studies. In addition, we describe a few tips for troubleshooting for mineralized tissues such as the skeleton.
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11
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Lin S, Zhang Q, Cao Z, Lu Y, Zhang H, Yan K, Liu Y, McKee MD, Qin C, Chen Z, Feng JQ. Constitutive nuclear expression of dentin matrix protein 1 fails to rescue the Dmp1-null phenotype. J Biol Chem 2014; 289:21533-43. [PMID: 24917674 PMCID: PMC4118114 DOI: 10.1074/jbc.m113.543330] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2013] [Revised: 06/02/2014] [Indexed: 12/12/2022] Open
Abstract
Dentin matrix protein 1 (DMP1) plays multiple roles in bone, tooth, phosphate homeostasis, kidney, salivary gland, reproductive cycles, and the development of cancer. In vitro studies have indicated two different biological mechanisms: 1) as a matrix protein, DMP1 interacts with αvβ3 integrin and activates MAP kinase signaling; and 2) DMP1 serves as a transcription co-factor. In vivo studies have demonstrated its key role in osteocytes. This study attempted to determine whether DMP1 functions as a transcription co-factor and regulates osteoblast functions. For gene expression comparisons using adenovirus constructs, we targeted the expression of DMP1 either to the nucleus only by replacing the endogenous signal peptide with a nuclear localization signal (NLS) sequence (referred to as (NLS)DMP1) or to the extracellular matrix as the WT type (referred to as (SP)DMP1) in MC3T3 osteoblasts. High levels of DMP1 in either form greatly increased osteogenic gene expression in an identical manner. However, the targeted (NLS)DMP1 transgene driven by a 3.6-kb rat Col 1α1 promoter in the nucleus of osteoblasts and osteocytes failed to rescue the phenotyope of Dmp1-null mice, whereas the (SP)DMP1 transgene rescued the rickets defect. These studies support the notion that DMP1 functions as an extracellular matrix protein, rather than as a transcription co-factor in vivo. We also show that DMP1 continues its expression in osteoblasts during postnatal development and that the deletion of Dmp1 leads to an increase in osteoblast proliferation. However, poor mineralization in the metaphysis indicates a critical role for DMP1 in both osteoblasts and osteocytes.
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Affiliation(s)
- Shuxian Lin
- From the Department of Biomedical Sciences, Texas A&M University, Baylor College of Dentistry, Dallas, Texas 75246, The State Key Laboratory Breeding Base of Basic Science of Stomatology (Hubei-MOST) and Key Laboratory of Oral Biomedicine, Ministry of Education, School and Hospital of Stomatology, Wuhan University, Wuhan 430072, Hubei, China
| | - Qi Zhang
- Laboratory of Oral Biomedical Science and Translational Medicine, Department of Endodontics, School of Stomatology, Tongji University, Shanghai 200092, China
| | - Zhengguo Cao
- The State Key Laboratory Breeding Base of Basic Science of Stomatology (Hubei-MOST) and Key Laboratory of Oral Biomedicine, Ministry of Education, School and Hospital of Stomatology, Wuhan University, Wuhan 430072, Hubei, China
| | - Yongbo Lu
- From the Department of Biomedical Sciences, Texas A&M University, Baylor College of Dentistry, Dallas, Texas 75246
| | - Hua Zhang
- From the Department of Biomedical Sciences, Texas A&M University, Baylor College of Dentistry, Dallas, Texas 75246
| | - Kevin Yan
- the Department of Biological Sciences, Columbia University, New York, New York 10027, and
| | - Ying Liu
- From the Department of Biomedical Sciences, Texas A&M University, Baylor College of Dentistry, Dallas, Texas 75246
| | - Marc D McKee
- the Faculty of Dentistry, and Department of Anatomy and Cell Biology, McGill University, Montreal, Quebec H3A 0G4, Canada
| | - Chunlin Qin
- From the Department of Biomedical Sciences, Texas A&M University, Baylor College of Dentistry, Dallas, Texas 75246
| | - Zhi Chen
- The State Key Laboratory Breeding Base of Basic Science of Stomatology (Hubei-MOST) and Key Laboratory of Oral Biomedicine, Ministry of Education, School and Hospital of Stomatology, Wuhan University, Wuhan 430072, Hubei, China,
| | - Jian Q Feng
- From the Department of Biomedical Sciences, Texas A&M University, Baylor College of Dentistry, Dallas, Texas 75246,
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12
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Bouleftour W, Boudiffa M, Wade-Gueye NM, Bouët G, Cardelli M, Laroche N, Vanden-Bossche A, Thomas M, Bonnelye E, Aubin JE, Vico L, Lafage-Proust MH, Malaval L. Skeletal development of mice lacking bone sialoprotein (BSP)--impairment of long bone growth and progressive establishment of high trabecular bone mass. PLoS One 2014; 9:e95144. [PMID: 24816232 PMCID: PMC4015893 DOI: 10.1371/journal.pone.0095144] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2013] [Accepted: 03/24/2014] [Indexed: 01/28/2023] Open
Abstract
Adult Ibsp-knockout mice (BSP−/−) display shorter stature, lower bone turnover and higher trabecular bone mass than wild type, the latter resulting from impaired bone resorption. Unexpectedly, BSP knockout also affects reproductive behavior, as female mice do not construct a proper "nest" for their offsprings. Multiple crossing experiments nonetheless indicated that the shorter stature and lower weight of BSP−/− mice, since birth and throughout life, as well as their shorter femur and tibia bones are independent of the genotype of the mothers, and thus reflect genetic inheritance. In BSP−/− newborns, µCT analysis revealed a delay in membranous primary ossification, with wider cranial sutures, as well as thinner femoral cortical bone and lower tissue mineral density, reflected in lower expression of bone formation markers. However, trabecular bone volume and osteoclast parameters of long bones do not differ between genotypes. Three weeks after birth, osteoclast number and surface drop in the mutants, concomitant with trabecular bone accumulation. The growth plates present a thinner hypertrophic zone in newborns with lower whole bone expression of IGF-1 and higher IHH in 6 days old BSP−/− mice. At 3 weeks the proliferating zone is thinner and the hypertrophic zone thicker in BSP−/− than in BSP+/+ mice of either sex, maybe reflecting a combination of lower chondrocyte proliferation and impaired cartilage resorption. Six days old BSP−/− mice display lower osteoblast marker expression but higher MEPE and higher osteopontin(Opn)/Runx2 ratio. Serum Opn is higher in mutants at day 6 and in adults. Thus, lack of BSP alters long bone growth and membranous/cortical primary bone formation and mineralization. Endochondral development is however normal in mutant mice and the accumulation of trabecular bone observed in adults develops progressively in the weeks following birth. Compensatory high Opn may allow normal endochondral development in BSP−/− mice, while impairing primary mineralization.
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Affiliation(s)
- Wafa Bouleftour
- Laboratoire de Biologie du Tissu Osseux and Institut National de la Santé et de la Recherche Médicale - U1059, Université de Lyon - Université Jean Monnet, Saint-Etienne, France
| | - Maya Boudiffa
- Laboratoire de Biologie du Tissu Osseux and Institut National de la Santé et de la Recherche Médicale - U1059, Université de Lyon - Université Jean Monnet, Saint-Etienne, France
| | - Ndeye Marième Wade-Gueye
- Laboratoire de Biologie du Tissu Osseux and Institut National de la Santé et de la Recherche Médicale - U1059, Université de Lyon - Université Jean Monnet, Saint-Etienne, France
| | - Guénaëlle Bouët
- Laboratoire de Biologie du Tissu Osseux and Institut National de la Santé et de la Recherche Médicale - U1059, Université de Lyon - Université Jean Monnet, Saint-Etienne, France
| | - Marco Cardelli
- Dept. of Molecular Genetics, University of Toronto, Toronto, Ontario, Canada
| | - Norbert Laroche
- Laboratoire de Biologie du Tissu Osseux and Institut National de la Santé et de la Recherche Médicale - U1059, Université de Lyon - Université Jean Monnet, Saint-Etienne, France
| | - Arnaud Vanden-Bossche
- Laboratoire de Biologie du Tissu Osseux and Institut National de la Santé et de la Recherche Médicale - U1059, Université de Lyon - Université Jean Monnet, Saint-Etienne, France
| | - Mireille Thomas
- Laboratoire de Biologie du Tissu Osseux and Institut National de la Santé et de la Recherche Médicale - U1059, Université de Lyon - Université Jean Monnet, Saint-Etienne, France
| | - Edith Bonnelye
- Institut National de la Santé et de la Recherche Médicale - U1033, Université de Lyon - Université Claude Bernard, Lyon, France
| | - Jane E. Aubin
- Dept. of Molecular Genetics, University of Toronto, Toronto, Ontario, Canada
| | - Laurence Vico
- Laboratoire de Biologie du Tissu Osseux and Institut National de la Santé et de la Recherche Médicale - U1059, Université de Lyon - Université Jean Monnet, Saint-Etienne, France
| | - Marie Hélène Lafage-Proust
- Laboratoire de Biologie du Tissu Osseux and Institut National de la Santé et de la Recherche Médicale - U1059, Université de Lyon - Université Jean Monnet, Saint-Etienne, France
| | - Luc Malaval
- Laboratoire de Biologie du Tissu Osseux and Institut National de la Santé et de la Recherche Médicale - U1059, Université de Lyon - Université Jean Monnet, Saint-Etienne, France
- * E-mail:
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Dentin matrix protein 1 and phosphate homeostasis are critical for postnatal pulp, dentin and enamel formation. Int J Oral Sci 2012; 4:189-95. [PMID: 23258378 PMCID: PMC3633060 DOI: 10.1038/ijos.2012.69] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023] Open
Abstract
Deletion or mutation of dentin matrix protein 1 (DMP1) leads to hypophosphatemic rickets and defects within the dentin. However, it is largely unknown if this pathological change is a direct role of DMP1 or an indirect role of phosphate (Pi) or both. It has also been previously shown that Klotho-deficient mice, which displayed a high Pi level due to a failure of Pi excretion, causes mild defects in the dentinal structure. This study was to address the distinct roles of DMP1 and Pi homeostasis in cell differentiation, apoptosis and mineralization of dentin and enamel. Our working hypothesis was that a stable Pi homeostasis is critical for postnatal tooth formation, and that DMP1 has an antiapoptotic role in both amelogenesis and dentinogenesis. To test this hypothesis, Dmp1-null (Dmp1(-/-)), Klotho-deficient (kl/kl), Dmp1/Klotho-double-deficient (Dmp1(-/-)/kl/kl) and wild-type (WT) mice were killed at the age of 6 weeks. Combinations of X-ray, microcomputed tomography (μCT), scanning electron microscopy (SEM), histology, apoptosis and immunohistochemical methods were used for characterization of dentin, enamel and pulp structures in these mutant mice. Our results showed that Dmp1(-/-) (a low Pi level) or kl/kl (a high Pi level) mice displayed mild dentin defects such as thin dentin and a reduction of dentin tubules. Neither deficient mouse line exhibited any apparent changes in enamel or pulp structure. However, the double-deficient mice (a high Pi level) displayed severe defects in dentin and enamel structures, including loss of dentinal tubules and enamel prisms, as well as unexpected ectopic ossification within the pulp root canal. TUNEL assay showed a sharp increase in apoptotic cells in ameloblasts and odontoblasts. Based on the above findings, we conclude that DMP1 has a protective role for odontoblasts and ameloblasts in a pro-apoptotic environment (a high Pi level).
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Abstract
PURPOSE Dmp1 (dentin matrix protein1) null mice (Dmp1(-/-)) display hypophosphatemic rickets with a sharp increase in fibroblast growth factor 23 (FGF23). Disruption of Klotho (the obligatory co-receptor of FGF23) results in hyperphosphatemia with ectopic calcifications formed in blood vessels and kidneys. To determine the role of DMP1 in both a hyperphosphatemic environment and within the ectopic calcifications, we created Dmp1/Klotho compound deficient (Dmp1(-/-)kl/kl) mice. PROCEDURES A combination of TUNEL, immunohistochemistry, TRAP, von Kossa, micro CT, bone histomorphometry, serum biochemistry and Scanning Electron Microscopy techniques were used to analyze the changes in blood vessels, kidney and bone for wild type control, Dmp1(-/-), Klotho deficient (kl/kl) and Dmp1(-/-)kl/kl animals. FINDINGS Interestingly, Dmp1(-/-)kl/kl mice show a dramatic improvement of rickets and an identical serum biochemical phenotype to kl/kl mice (extremely high FGF23, hyperphosphatemia and reduced parathyroid hormone (PTH) levels). Unexpectedly, Dmp1(-/-)kl/kl mice presented elevated levels of apoptosis in osteocytes, endothelial and vascular smooth muscle cells in small and large blood vessels, and within the kidney as well as dramatic increase in ectopic calcification in all these tissues, as compared to kl/kl. CONCLUSION These findings suggest that DMP1 has an anti-apoptotic role in hyperphosphatemia. Discovering this novel protective role of DMP1 may have clinical relevance in protecting the cells from apoptosis in high-phosphate environments as observed in chronic kidney disease (CKD).
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