1
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Heffer A, Lee C, Mayernik JP, Holt JC, Kiernan AE. Notch1 is Required to Maintain Supporting Cell Identity and Vestibular Function during Maturation of the Mammalian Balance Organs. J Neurosci 2025; 45:e1365242024. [PMID: 39779370 PMCID: PMC11867012 DOI: 10.1523/jneurosci.1365-24.2024] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2024] [Revised: 11/27/2024] [Accepted: 12/05/2024] [Indexed: 01/11/2025] Open
Abstract
The inner ear houses both hearing and balance sensory modalities. The hearing and balance organs consist of similar cell types, including sensory hair cells and associated supporting cells. Previously we showed that Notch1 is required for maintaining supporting cell survival during cochlear maturation. To understand the role of Notch during vestibular maturation, we deleted Notch1 from the vestibular organs of both male and female mice at birth. Histological analyses showed a reduction of supporting cells accompanied by an increase in type II hair cells, indicating a conversion of supporting cells to hair cells. Analysis of mature sensory organs indicate the converted hair cells survive, despite a severe reduction of supporting cells. Vestibular sensory evoked potentials (VsEPs), thought to be generated within the striola regions of the maculae, were absent, indicating that NOTCH1 is critical for striolar function. Specialized type I hair cells in the striola failed to develop the complex calyces typical of these cells. Notch1 mutants did not exhibit vestibular behaviors such as circling and head shaking but showed difficulties with tests of balance and swimming. These results indicate that, unlike the cochlea, supporting cells in balance organs retain the plasticity to convert to hair cells which can survive into adulthood. Despite hair cell survival, vestibular function is compromised likely due to the loss of supporting cells and altered innervation.
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MESH Headings
- Animals
- Receptor, Notch1/genetics
- Receptor, Notch1/physiology
- Receptor, Notch1/deficiency
- Receptor, Notch1/metabolism
- Mice
- Female
- Male
- Postural Balance/physiology
- Vestibule, Labyrinth/growth & development
- Vestibule, Labyrinth/physiology
- Vestibule, Labyrinth/cytology
- Hair Cells, Auditory/physiology
- Hair Cells, Vestibular/physiology
- Mice, Knockout
- Mice, Inbred C57BL
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Affiliation(s)
- Alison Heffer
- Flaum Eye Institute, Department of Ophthalmology, University of Rochester Medical Center, Rochester, New York 14642
| | - Choongheon Lee
- Departments of Otolaryngology, University of Rochester, Rochester, New York 14642
- Mechanical Engineering, University of Rochester, Rochester, New York 14642
| | - Joseph P Mayernik
- Flaum Eye Institute, Department of Ophthalmology, University of Rochester Medical Center, Rochester, New York 14642
| | - Joseph C Holt
- Departments of Otolaryngology, University of Rochester, Rochester, New York 14642
- Neuroscience, University of Rochester, Rochester, New York 14642
| | - Amy E Kiernan
- Flaum Eye Institute, Department of Ophthalmology, University of Rochester Medical Center, Rochester, New York 14642
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2
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Docshin P, Panshin D, Malashicheva A. Molecular Interplay in Cardiac Fibrosis: Exploring the Functions of RUNX2, BMP2, and Notch. Rev Cardiovasc Med 2024; 25:368. [PMID: 39484128 PMCID: PMC11522771 DOI: 10.31083/j.rcm2510368] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2024] [Revised: 07/26/2024] [Accepted: 07/31/2024] [Indexed: 11/03/2024] Open
Abstract
Cardiac fibrosis, characterized by the excessive deposition of extracellular matrix proteins, significantly contributes to the morbidity and mortality associated with cardiovascular diseases. This article explores the complex interplay between Runt-related transcription factor 2 (RUNX2), bone morphogenetic protein 2 (BMP2), and Notch signaling pathways in the pathogenesis of cardiac fibrosis. Each of these pathways plays a crucial role in the regulation of cellular functions and interactions that underpin fibrotic processes in the heart. Through a detailed review of current research, we highlight how the crosstalk among RUNX2, BMP2, and Notch not only facilitates our understanding of the fibrotic mechanisms but also points to potential biomolecular targets for intervention. This article delves into the regulatory networks, identifies key molecular mediators, and discusses the implications of these signaling pathways in cardiac structural remodeling. By synthesizing findings from recent studies, we provide insights into the cellular and molecular mechanisms that could guide future research directions, aiming to uncover new therapeutic strategies to manage and treat cardiac fibrosis effectively.
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Affiliation(s)
- Pavel Docshin
- Laboratory of Regenerative Biomedicine, Institute of Cytology Russian Academy of Science, 194064 St. Petersburg, Russia
| | - Daniil Panshin
- Laboratory of Regenerative Biomedicine, Institute of Cytology Russian Academy of Science, 194064 St. Petersburg, Russia
| | - Anna Malashicheva
- Laboratory of Regenerative Biomedicine, Institute of Cytology Russian Academy of Science, 194064 St. Petersburg, Russia
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3
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Lui PP, Xu JZ, Aziz H, Sen M, Ali N. Jagged-1+ skin Tregs modulate cutaneous wound healing. Sci Rep 2024; 14:20999. [PMID: 39251686 PMCID: PMC11385218 DOI: 10.1038/s41598-024-71512-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2024] [Accepted: 08/28/2024] [Indexed: 09/11/2024] Open
Abstract
Skin-resident regulatory T cells (Tregs) play an irreplaceable role in orchestrating cutaneous immune homeostasis and repair, including the promotion of hair regeneration via the Notch signaling ligand Jagged-1 (Jag1). While skin Tregs are indispensable for facilitating tissue repair post-wounding, it remains unknown if Jag1-expressing skin Tregs impact wound healing. Using a tamoxifen inducible Foxp3creERT2Jag1fl/fl model, we show that loss of functional Jag1 in Tregs significantly delays the rate of full-thickness wound closure. Unlike in hair regeneration, skin Tregs do not utilize Jag1 to impact epithelial stem cells during wound healing. Instead, mice with Treg-specific Jag1 ablation exhibit a significant reduction in Ly6G + neutrophil accumulation at the wound site. However, during both homeostasis and wound healing, the loss of Jag1 in Tregs does not impact the overall abundance or activation profile of immune cell targets in the skin, such as CD4+ and CD8+ T cells, or pro-inflammatory macrophages. This collectively suggests that skin Tregs may utilize Jag1-Notch signalling to co-ordinate innate cell recruitment under conditions of injury but not homeostasis. Overall, our study demonstrates the importance of Jag1 expression in Tregs to facilitate adequate wound repair in the skin.
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Affiliation(s)
- Prudence PokWai Lui
- Peter Gorer Department of Immunobiology, King's College London, London, SE1 9RT, UK
- Centre for Gene Therapy and Regenerative Medicine, King's College London, London, SE1 9RT, UK
| | - Jessie Z Xu
- Peter Gorer Department of Immunobiology, King's College London, London, SE1 9RT, UK
- Centre for Gene Therapy and Regenerative Medicine, King's College London, London, SE1 9RT, UK
| | - Hafsah Aziz
- Peter Gorer Department of Immunobiology, King's College London, London, SE1 9RT, UK
- Centre for Gene Therapy and Regenerative Medicine, King's College London, London, SE1 9RT, UK
| | - Monica Sen
- Peter Gorer Department of Immunobiology, King's College London, London, SE1 9RT, UK
- Centre for Gene Therapy and Regenerative Medicine, King's College London, London, SE1 9RT, UK
| | - Niwa Ali
- Peter Gorer Department of Immunobiology, King's College London, London, SE1 9RT, UK.
- Centre for Gene Therapy and Regenerative Medicine, King's College London, London, SE1 9RT, UK.
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4
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Heffer A, Lee C, Holt JC, Kiernan AE. Notch1 is required to maintain supporting cell identity and vestibular function during maturation of the mammalian balance organs. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.06.21.600098. [PMID: 38948821 PMCID: PMC11212955 DOI: 10.1101/2024.06.21.600098] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/02/2024]
Abstract
The inner ear houses two sensory modalities: the hearing organ, located in the cochlea, and the balance organs, located throughout the vestibular regions of the ear. Both hearing and vestibular sensory regions are composed of similar cell types, including hair cells and associated supporting cells. Recently, we showed that Notch1 is required for maintaining supporting cell survival postnatally during cochlear maturation. However, it is not known whether Notch1 plays a similar role in the balance organs of the inner ear. To characterize the role of Notch during vestibular maturation, we conditionally deleted Notch1 from Sox2-expressing cells of the vestibular organs in the mouse at P0/P1. Histological analyses showed a dramatic loss of supporting cells accompanied by an increase in type II hair cells without cell death, indicating the supporting cells are converting to hair cells in the maturing vestibular regions. Analysis of 6-week old animals indicate that the converted hair cells survive, despite the reduction of supporting cells. Interestingly, measurements of vestibular sensory evoked potentials (VsEPs), known to be generated in the striolar regions of the vestibular afferents in the maculae, failed to show a response, indicating that NOTCH1 expression is critical for striolar function postnatally. Consistent with this, we find that the specialized type I hair cells in the striola fail to develop the complex calyces typical of these cells. These defects are likely due to the reduction in supporting cells, which have previously been shown to express factors critical for the striolar region. Similar to other mutants that lack proper striolar development, Notch1 mutants do not exhibit typical vestibular behaviors such as circling and head shaking, but do show difficulties in some vestibular tests, including the balance beam and forced swim test. These results indicate that, unlike the hearing organ in which the supporting cells undergo cell death, supporting cells in the balance regions retain the ability to convert to hair cells during maturation, which survive into adulthood despite the reduction in supporting cells.
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Affiliation(s)
- Alison Heffer
- Flaum Eye Institute, Department of Ophthalmology, University of Rochester Medical Center, Rochester, New York, 14642, USA
| | - Choongheon Lee
- Department of Otolaryngology, University of Rochester, Rochester, NY, 14642, USA
| | - Joseph C. Holt
- Department of Otolaryngology, University of Rochester, Rochester, NY, 14642, USA
- Dept. of Neuroscience, University of Rochester, Rochester, New York 14642, USA
| | - Amy E. Kiernan
- Flaum Eye Institute, Department of Ophthalmology, University of Rochester Medical Center, Rochester, New York, 14642, USA
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5
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Yoshihara M, Nakayama T, Takahashi S. Chromatin accessibility analysis suggested vascular induction of the biliary epithelium via the Notch signaling pathway in the human liver. BMC Res Notes 2023; 16:379. [PMID: 38129911 PMCID: PMC10734141 DOI: 10.1186/s13104-023-06674-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2023] [Accepted: 12/15/2023] [Indexed: 12/23/2023] Open
Abstract
The biliary epithelial cells (cholangiocytes) in the liver originate from undifferentiated liver parenchymal cells (hepatoblasts) that are located adjacent to the portal vein. This differentiation process is driven by Notch signaling, which is recognized for generating salt-and-pepper (fine-grained) patterns, in contrast to one- or two-cell layer (spatially confined) patterning in cholangiocyte differentiation. It is unclear how Notch signaling acts and localizes only in cholangiocytes. A computer simulation study suggested that low production rates of the ligands or receptors of Notch signaling are crucial for the spatially confined patterning, although biochemical examination is lacking. Here, we analyzed a publicly available single-cell ATAC-sequencing dataset from human fetal liver samples. We showed high chromatin accessibility for the ligands only in vascular cells, while that for the receptor is limited to a small population of hepatoblasts. This finding strengthens the previously proposed idea that low production rates of the ligands or receptors of Notch signaling enable vascular induction of cholangiocytes.
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Affiliation(s)
- Masaharu Yoshihara
- Department of Primary Care and Medical Education, Institute of Medicine, University of Tsukuba, Tsukuba, Japan.
- Laboratory Animal Resource Center, 1-1-1 Tennodai, Tsukuba, Ibaraki, 305-8575, Japan.
| | - Takahiro Nakayama
- College of Medicine, School of Medicine and Health Sciences, University of Tsukuba, Tsukuba, Japan
| | - Satoru Takahashi
- Department of Anatomy and Embryology, Institute of Medicine, University of Tsukuba, Tsukuba, Japan
- Transborder Medical Research Center, Institute of Medicine, University of Tsukuba, Tsukuba, Japan
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6
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Yoshihara M, Takahashi S. Recent advances in in situ Notch signaling measurement. Front Cell Dev Biol 2023; 11:1244105. [PMID: 37576594 PMCID: PMC10416437 DOI: 10.3389/fcell.2023.1244105] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2023] [Accepted: 07/21/2023] [Indexed: 08/15/2023] Open
Abstract
Notch signaling is necessary for the development of many organ systems, including the nervous system, biliary system, and visual and auditory sensory systems. This signaling pathway is composed of DSL ligands and Notch receptors. Upon the interaction of those components between neighboring cells, the intracellular domain of the Notch receptor is cleaved from the cell membrane to act as a transcription factor. To date, many mechanistic insights, including lateral inhibition and lateral induction, have been proposed from observation of patterning morphogenesis and expression profiles of Notch signaling-associated molecules. The lack of a direct measurement method for Notch signaling, however, has impeded the examination of those mechanistic insights. In this mini-review, recent advances in the direct measurement of Notch signaling are introduced with a focus on the application of genetic modification of Notch receptors with the components of the Cre/loxP system and Gal4/UAS system. The combination of such conventional genetic techniques is opening a new era in Notch signaling biology by direct visualization of Notch "signaling" in addition to Notch signaling-associated molecules.
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Affiliation(s)
- Masaharu Yoshihara
- Department of Primary Care and Medical Education, Institute of Medicine, University of Tsukuba, Tsukuba, Japan
| | - Satoru Takahashi
- Department of Anatomy and Embryology, Institute of Medicine, University of Tsukuba, Tsukuba, Japan
- Transborder Medical Research Center, Institute of Medicine, University of Tsukuba, Tsukuba, Japan
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7
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van der Valk WH, van Beelen ESA, Steinhart MR, Nist-Lund C, Osorio D, de Groot JCMJ, Sun L, van Benthem PPG, Koehler KR, Locher H. A single-cell level comparison of human inner ear organoids with the human cochlea and vestibular organs. Cell Rep 2023; 42:112623. [PMID: 37289589 PMCID: PMC10592453 DOI: 10.1016/j.celrep.2023.112623] [Citation(s) in RCA: 19] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2022] [Revised: 02/21/2023] [Accepted: 05/23/2023] [Indexed: 06/10/2023] Open
Abstract
Inner ear disorders are among the most common congenital abnormalities; however, current tissue culture models lack the cell type diversity to study these disorders and normal otic development. Here, we demonstrate the robustness of human pluripotent stem cell-derived inner ear organoids (IEOs) and evaluate cell type heterogeneity by single-cell transcriptomics. To validate our findings, we construct a single-cell atlas of human fetal and adult inner ear tissue. Our study identifies various cell types in the IEOs including periotic mesenchyme, type I and type II vestibular hair cells, and developing vestibular and cochlear epithelium. Many genes linked to congenital inner ear dysfunction are confirmed to be expressed in these cell types. Additional cell-cell communication analysis within IEOs and fetal tissue highlights the role of endothelial cells on the developing sensory epithelium. These findings provide insights into this organoid model and its potential applications in studying inner ear development and disorders.
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Affiliation(s)
- Wouter H van der Valk
- OtoBiology Leiden, Department of Otorhinolaryngology and Head & Neck Surgery, Leiden University Medical Center, 2333 ZA Leiden, the Netherlands; The Novo Nordisk Foundation Center for Stem Cell Medicine (reNEW), Leiden University Medical Center, 2333 ZA Leiden, the Netherlands; Department of Otolaryngology, Boston Children's Hospital, Boston, MA 02115, USA; F.M. Kirby Neurobiology Center, Boston Children's Hospital, Boston, MA 02115, USA; Department of Otolaryngology-Head and Neck Surgery, Harvard Medical School, Boston, MA 02115, USA.
| | - Edward S A van Beelen
- OtoBiology Leiden, Department of Otorhinolaryngology and Head & Neck Surgery, Leiden University Medical Center, 2333 ZA Leiden, the Netherlands
| | - Matthew R Steinhart
- Department of Otolaryngology, Boston Children's Hospital, Boston, MA 02115, USA; F.M. Kirby Neurobiology Center, Boston Children's Hospital, Boston, MA 02115, USA; Department of Otolaryngology-Head and Neck Surgery, Indiana University School of Medicine, Indianapolis, IN 46202, USA; Medical Neuroscience Graduate Program, Indiana University School of Medicine, Indianapolis, IN 46202, USA
| | - Carl Nist-Lund
- Department of Otolaryngology, Boston Children's Hospital, Boston, MA 02115, USA; F.M. Kirby Neurobiology Center, Boston Children's Hospital, Boston, MA 02115, USA; Program in Neuroscience, Harvard Medical School, Boston, MA 02115, USA
| | - Daniel Osorio
- Research Computing, Department of Information Technology, Boston Children's Hospital, Boston, MA 02115, USA
| | - John C M J de Groot
- OtoBiology Leiden, Department of Otorhinolaryngology and Head & Neck Surgery, Leiden University Medical Center, 2333 ZA Leiden, the Netherlands
| | - Liang Sun
- Research Computing, Department of Information Technology, Boston Children's Hospital, Boston, MA 02115, USA
| | - Peter Paul G van Benthem
- OtoBiology Leiden, Department of Otorhinolaryngology and Head & Neck Surgery, Leiden University Medical Center, 2333 ZA Leiden, the Netherlands
| | - Karl R Koehler
- Department of Otolaryngology, Boston Children's Hospital, Boston, MA 02115, USA; F.M. Kirby Neurobiology Center, Boston Children's Hospital, Boston, MA 02115, USA; Department of Otolaryngology-Head and Neck Surgery, Harvard Medical School, Boston, MA 02115, USA; Department of Plastic and Oral Surgery, Boston Children's Hospital, Boston, MA 02115, USA.
| | - Heiko Locher
- OtoBiology Leiden, Department of Otorhinolaryngology and Head & Neck Surgery, Leiden University Medical Center, 2333 ZA Leiden, the Netherlands; The Novo Nordisk Foundation Center for Stem Cell Medicine (reNEW), Leiden University Medical Center, 2333 ZA Leiden, the Netherlands.
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8
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Ueda Y, Nakamura T, Nie J, Solivais AJ, Hoffman JR, Daye BJ, Hashino E. Defining developmental trajectories of prosensory cells in human inner ear organoids at single-cell resolution. Development 2023; 150:dev201071. [PMID: 37381908 PMCID: PMC10323240 DOI: 10.1242/dev.201071] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2022] [Accepted: 05/24/2023] [Indexed: 06/29/2023]
Abstract
The inner ear sensory epithelia contain mechanosensitive hair cells and supporting cells. Both cell types arise from SOX2-expressing prosensory cells, but the mechanisms underlying the diversification of these cell lineages remain unclear. To determine the transcriptional trajectory of prosensory cells, we established a SOX2-2A-ntdTomato human embryonic stem cell line using CRISPR/Cas9, and performed single-cell RNA-sequencing analyses with SOX2-positive cells isolated from inner ear organoids at various time points between differentiation days 20 and 60. Our pseudotime analysis suggests that vestibular type II hair cells arise primarily from supporting cells, rather than bi-fated prosensory cells in organoids. Moreover, ion channel- and ion-transporter-related gene sets were enriched in supporting cells versus prosensory cells, whereas Wnt signaling-related gene sets were enriched in hair cells versus supporting cells. These findings provide valuable insights into how prosensory cells give rise to hair cells and supporting cells during human inner ear development, and may provide a clue to promote hair cell regeneration from resident supporting cells in individuals with hearing loss or balance disorders.
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Affiliation(s)
- Yoshitomo Ueda
- Department of Otolaryngology-Head and Neck Surgery, Indiana University School of Medicine, Indianapolis, IN 46202, USA
| | - Takashi Nakamura
- Department of Otolaryngology-Head and Neck Surgery, Indiana University School of Medicine, Indianapolis, IN 46202, USA
- Department of Otolaryngology-Head and Neck Surgery, Kyoto Prefectural University of Medicine, Kyoto 602-8566, Japan
| | - Jing Nie
- Department of Otolaryngology-Head and Neck Surgery, Indiana University School of Medicine, Indianapolis, IN 46202, USA
| | - Alexander J. Solivais
- Department of Otolaryngology-Head and Neck Surgery, Indiana University School of Medicine, Indianapolis, IN 46202, USA
| | - John R. Hoffman
- Department of Otolaryngology-Head and Neck Surgery, Indiana University School of Medicine, Indianapolis, IN 46202, USA
| | - Becca J. Daye
- Department of Otolaryngology-Head and Neck Surgery, Indiana University School of Medicine, Indianapolis, IN 46202, USA
| | - Eri Hashino
- Department of Otolaryngology-Head and Neck Surgery, Indiana University School of Medicine, Indianapolis, IN 46202, USA
- Stark Neurosciences Research Institute, Indiana University School of Medicine, Indianapolis, IN 46202, USA
- Department of Anatomy and Cell Biology, Indiana University School of Medicine, Indianapolis, IN 46202, USA
- Department of Pharmacology and Toxicology, Indiana University School of Medicine, Indianapolis, IN 46202, USA
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9
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Promotion of In Vitro Hair Cell-like Cell Differentiation from Human Embryonic Stem Cells through the Regulation of Notch Signaling. Metabolites 2021; 11:metabo11120873. [PMID: 34940631 PMCID: PMC8709284 DOI: 10.3390/metabo11120873] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2021] [Revised: 12/13/2021] [Accepted: 12/13/2021] [Indexed: 11/25/2022] Open
Abstract
The Notch signaling pathway plays an important role in otic neurogenesis by regulating the differentiation of inner ear hair cells and supporting cells. Notch-regulated differentiation is required for the regeneration of hair cells in the inner ear. The temporal expression pattern of Notch ligands and receptors during in vitro hair cell-like cell differentiation from human embryonic stem cells (hESCs) was detected by quantitative reverse transcription-polymerase chain reaction (qRT-PCR). Subsequently, pAJ-U6-shRNA-CMV-Puro/GFP recombinant lentiviral vectors encoding short hairpin RNAs were used to silence JAG-1, JAG-2, and DLL-1, according to the temporal expression pattern of Notch ligands. Then, the effect of each ligand on the in vitro differentiation of hair cells was examined by RT-PCR, immunofluorescence, and scanning electron microscopy (SEM). The results showed that the individual deletion of JAG-2 or DLL-1 had no significant effect on the differentiation of hair cell-like cells. However, the simultaneous inhibition of both DLL-1 and JAG-2 increased the number of hair cell-like cells and decreased the number of supporting cells. JAG-2 and DLL-1 may have a synergistic role in in vitro hair cell differentiation.
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10
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Liu W, Johansson Å, Rask-Andersen H, Rask-Andersen M. A combined genome-wide association and molecular study of age-related hearing loss in H. sapiens. BMC Med 2021; 19:302. [PMID: 34847940 PMCID: PMC8638543 DOI: 10.1186/s12916-021-02169-0] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/11/2021] [Accepted: 10/21/2021] [Indexed: 02/08/2023] Open
Abstract
BACKGROUND Sensorineural hearing loss is one of the most common sensory deficiencies. However, the molecular contribution to age-related hearing loss is not fully elucidated. METHODS We performed genome-wide association studies (GWAS) for hearing loss-related traits in the UK Biobank (N = 362,396) and selected a high confidence set of ten hearing-associated gene products for staining in human cochlear samples: EYA4, LMX1A, PTK2/FAK, UBE3B, MMP2, SYNJ2, GRM5, TRIOBP, LMO-7, and NOX4. RESULTS All proteins were found to be expressed in human cochlear structures. Our findings illustrate cochlear structures that mediate mechano-electric transduction of auditory stimuli, neuronal conductance, and neuronal plasticity to be involved in age-related hearing loss. CONCLUSIONS Our results suggest common genetic variation to influence structural resilience to damage as well as cochlear recovery after trauma, which protect against accumulated damage to cochlear structures and the development of hearing loss over time.
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Affiliation(s)
- Wei Liu
- Department of Surgical Sciences, Section of Otorhinolaryngology and Head & Neck Surgery, Uppsala University, SE-751 85, Uppsala, Sweden
| | - Åsa Johansson
- Department of Immunology, Genetics and Pathology, Science for Life Laboratory, Uppsala University, Uppsala, Sweden
| | - Helge Rask-Andersen
- Department of Surgical Sciences, Section of Otorhinolaryngology and Head & Neck Surgery, Uppsala University, SE-751 85, Uppsala, Sweden.
| | - Mathias Rask-Andersen
- Department of Immunology, Genetics and Pathology, Science for Life Laboratory, Uppsala University, Uppsala, Sweden.
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11
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Pas K, Laboy-Segarra S, Lee J. Systems of pattern formation within developmental biology. PROGRESS IN BIOPHYSICS AND MOLECULAR BIOLOGY 2021; 167:18-25. [PMID: 34619250 DOI: 10.1016/j.pbiomolbio.2021.09.005] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/21/2021] [Revised: 08/19/2021] [Accepted: 09/30/2021] [Indexed: 01/10/2023]
Abstract
Applications of mathematical models to developmental biology have provided helpful insight into various subfields, ranging from the patterning of animal skin to the development of complex organ systems. Systems involved in patterning within morphology present a unique path to explain self-organizing systems. Current efforts show that patterning systems, notably Reaction-Diffusion and specific signaling pathways, provide insight for explaining morphology and could provide novel applications revolving around the formation of biological systems. Furthermore, the application of pattern formation provides a new perspective on understanding developmental biology and pathology research to study molecular mechanisms. The current review is to cover and take a more in-depth overlook at current applications of patterning systems while also building on the principles of patterning of future research in predictive medicine.
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Affiliation(s)
- Kristofor Pas
- Department of Bioengineering, University of Texas at Arlington, Arlington, TX, USA
| | | | - Juhyun Lee
- Department of Bioengineering, University of Texas at Arlington, Arlington, TX, USA; Department of Medical Education, TCU and UNTHSC School of Medicine, Fort Worth, TX, 76107, USA.
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12
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Kwan KY, White PM. Understanding the differentiation and epigenetics of cochlear sensory progenitors in pursuit of regeneration. Curr Opin Otolaryngol Head Neck Surg 2021; 29:366-372. [PMID: 34374667 PMCID: PMC8452321 DOI: 10.1097/moo.0000000000000741] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
PURPOSE OF REVIEW Sensory hair cells (HCs) of the inner ear are responsible for our ability to hear and balance. Loss of these cells results in hearing loss. Stem cell replacement and in situ regeneration have the potential to replace lost HCs. Newly discovered contributions of transcription factor regulatory networks and epigenetic mechanisms in regulating HC differentiation and regeneration are placed into context of the literature. RECENT FINDINGS A wealth of new data has helped to define cochlear sensory progenitors in their developmental trajectories. This includes transcription factor networks, epigenetic manipulations, and cochlear HC subtype specification. SUMMARY Understanding how sensory progenitors differ and how HC subtypes arise will substantially inform efforts in hearing restoration.
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Affiliation(s)
- Kelvin Y. Kwan
- Department of Cell Biology & Neuroscience, Rutgers University, Piscataway, New Jersey
| | - Patricia M. White
- Department of Neuroscience, Ernest J. Del Monte Institute of Neuroscience, University of Rochester School of Medicine and Dentistry, Rochester, New York, USA
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13
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The Notch Ligand Jagged1 Is Required for the Formation, Maintenance, and Survival of Hensen's Cells in the Mouse Cochlea. J Neurosci 2020; 40:9401-9413. [PMID: 33127852 DOI: 10.1523/jneurosci.1192-20.2020] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2020] [Revised: 10/16/2020] [Accepted: 10/23/2020] [Indexed: 01/09/2023] Open
Abstract
During cochlear development, the Notch ligand JAGGED 1 (JAG1) plays an important role in the specification of the prosensory region, which gives rise to sound-sensing hair cells and neighboring supporting cells (SCs). While JAG1's expression is maintained in SCs through adulthood, the function of JAG1 in SC development is unknown. Here, we demonstrate that JAG1 is essential for the formation and maintenance of Hensen's cells, a highly specialized SC subtype located at the edge of the auditory epithelium. Using Sox2 CreERT2/+::Jag1loxP/loxP mice of both genders, we show that Jag1 deletion at the onset of differentiation, at embryonic day 14.5, disrupted Hensen's cell formation. Similar loss of Hensen's cells was observed when Jag1 was deleted after Hensen's cell formation at postnatal day (P) 0/P1 and fate-mapping analysis revealed that in the absence of Jag1, some Hensen's cells die, but others convert into neighboring Claudius cells. In support of a role for JAG1 in cell survival, genes involved in mitochondrial function and protein synthesis were downregulated in the sensory epithelium of P0 cochlea lacking Jag1 Finally, using Fgfr3-iCreERT2 ::Jag1loxP/loxP mice to delete Jag1 at P0, we observed a similar loss of Hensen's cells and found that adult Jag1 mutant mice have hearing deficits at the low-frequency range.SIGNIFICANCE STATEMENT Hensen's cells play an essential role in the development and homeostasis of the cochlea. Defects in the biophysical or functional properties of Hensen's cells have been linked to auditory dysfunction and hearing loss. Despite their importance, surprisingly little is known about the molecular mechanisms that guide their development. Morphologic and fate-mapping analyses in our study revealed that, in the absence of the Notch ligand JAGGED1, Hensen's cells died or converted into Claudius cells, which are specialized epithelium-like cells outside the sensory epithelium. Confirming a link between JAGGED1 and cell survival, transcriptional profiling showed that JAGGED1 maintains genes critical for mitochondrial function and tissue homeostasis. Finally, auditory phenotyping revealed that JAGGED1's function in supporting cells is necessary for low-frequency hearing.
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