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Fan B, Lu F, Du WJ, Chen J, An XG, Wang RF, Li W, Song YL, Zha DJ, Chen FQ. PTEN inhibitor bisperoxovanadium protects against noise-induced hearing loss. Neural Regen Res 2023; 18:1601-1606. [PMID: 36571368 PMCID: PMC10075117 DOI: 10.4103/1673-5374.358606] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Studies have shown that phosphatase and tensin homolog deleted on chromosome ten (PTEN) participates in the regulation of cochlear hair cell survival. Bisperoxovanadium protects against neurodegeneration by inhibiting PTEN expression. However, whether bisperoxovanadium can protect against noise-induced hearing loss and the underlying mechanism remains unclear. In this study, we established a mouse model of noise-induced hearing loss by exposure to 105 dB sound for 2 hours. We found that PTEN expression was increased in the organ of Corti, including outer hair cells, inner hair cells, and lateral wall tissues. Intraperitoneal administration of bisperoxovanadium decreased the auditory threshold and the loss of cochlear hair cells and inner hair cell ribbons. In addition, noise exposure decreased p-PI3K and p-Akt levels. Bisperoxovanadium preconditioning or PTEN knockdown upregulated the activity of PI3K-Akt. Bisperoxovanadium also prevented H2O2-induced hair cell death by reducing mitochondrial reactive oxygen species generation in cochlear explants. These findings suggest that bisperoxovanadium reduces noise-induced hearing injury and reduces cochlear hair cell loss.
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Affiliation(s)
- Bei Fan
- Department of Otolaryngology Head and Neck Surgery, Xijing Hospital, Fourth Military Medical University, Xi'an, Shaanxi Province, China
| | - Fei Lu
- Department of Otolaryngology Head and Neck Surgery, Xijing Hospital, Fourth Military Medical University, Xi'an, Shaanxi Province, China
| | - Wei-Jia Du
- Department of Otolaryngology Head and Neck Surgery, Xijing Hospital, Fourth Military Medical University, Xi'an, Shaanxi Province, China
| | - Jun Chen
- Department of Otolaryngology Head and Neck Surgery, Xijing Hospital, Fourth Military Medical University, Xi'an, Shaanxi Province, China
| | - Xiao-Gang An
- Department of Otolaryngology Head and Neck Surgery, Xijing Hospital, Fourth Military Medical University, Xi'an, Shaanxi Province, China
| | - Ren-Feng Wang
- Department of Otolaryngology Head and Neck Surgery, Xijing Hospital, Fourth Military Medical University, Xi'an, Shaanxi Province, China
| | - Wei Li
- Department of Otolaryngology Head and Neck Surgery, Xijing Hospital, Fourth Military Medical University, Xi'an, Shaanxi Province, China
| | - Yong-Li Song
- Department of Otolaryngology Head and Neck Surgery, Xijing Hospital, Fourth Military Medical University, Xi'an, Shaanxi Province, China
| | - Ding-Jun Zha
- Department of Otolaryngology Head and Neck Surgery, Xijing Hospital, Fourth Military Medical University, Xi'an, Shaanxi Province, China
| | - Fu-Quan Chen
- Department of Otolaryngology Head and Neck Surgery, Xijing Hospital, Fourth Military Medical University, Xi'an, Shaanxi Province, China
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Hausott B, Glueckert R, Schrott-Fischer A, Klimaschewski L. Signal Transduction Regulators in Axonal Regeneration. Cells 2022; 11:cells11091537. [PMID: 35563843 PMCID: PMC9104247 DOI: 10.3390/cells11091537] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2022] [Revised: 04/27/2022] [Accepted: 04/28/2022] [Indexed: 11/16/2022] Open
Abstract
Intracellular signal transduction in response to growth factor receptor activation is a fundamental process during the regeneration of the nervous system. In this context, intracellular inhibitors of neuronal growth factor signaling have become of great interest in the recent years. Among them are the prominent signal transduction regulators Sprouty (SPRY) and phosphatase and tensin homolog deleted on chromosome 10 (PTEN), which interfere with major signaling pathways such as extracellular signal-regulated kinase (ERK) or phosphoinositide 3-kinase (PI3K)/Akt in neurons and glial cells. Furthermore, SPRY and PTEN are themselves tightly regulated by ubiquitin ligases such as c-casitas b-lineage lymphoma (c-CBL) or neural precursor cell expressed developmentally down-regulated protein 4 (NEDD4) and by different microRNAs (miRs) including miR-21 and miR-222. SPRY, PTEN and their intracellular regulators play an important role in the developing and the lesioned adult central and peripheral nervous system. This review will focus on the effects of SPRY and PTEN as well as their regulators in various experimental models of axonal regeneration in vitro and in vivo. Targeting these signal transduction regulators in the nervous system holds great promise for the treatment of neurological injuries in the future.
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Affiliation(s)
- Barbara Hausott
- Institute of Neuroanatomy, Medical University Innsbruck, 6020 Innsbruck, Austria;
- Correspondence:
| | - Rudolf Glueckert
- Department of Otorhinolaryngology, Medical University Innsbruck, 6020 Innsbruck, Austria; (R.G.); (A.S.-F.)
| | - Anneliese Schrott-Fischer
- Department of Otorhinolaryngology, Medical University Innsbruck, 6020 Innsbruck, Austria; (R.G.); (A.S.-F.)
| | - Lars Klimaschewski
- Institute of Neuroanatomy, Medical University Innsbruck, 6020 Innsbruck, Austria;
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Liu W, Xu L, Wang X, Zhang D, Sun G, Wang M, Wang M, Han Y, Chai R, Wang H. PRDX1 activates autophagy via the PTEN-AKT signaling pathway to protect against cisplatin-induced spiral ganglion neuron damage. Autophagy 2021; 17:4159-4181. [PMID: 33749526 PMCID: PMC8726717 DOI: 10.1080/15548627.2021.1905466] [Citation(s) in RCA: 103] [Impact Index Per Article: 34.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Spiral ganglion neurons (SGNs) are auditory neurons that relay sound signals from the inner ear to the brainstem. The ototoxic drug cisplatin can damage SGNs and thus lead to sensorineural hearing loss (SNHL), and there are currently no methods for preventing or treating this. Macroautophagy/autophagy plays a critical role in SGN development, but the effect of autophagy on cisplatin-induced SGN injury is unclear. Here, we first found that autophagic flux was activated in SGNs after cisplatin damage. The SGN apoptosis and related hearing loss induced by cisplatin were alleviated after co-treatment with the autophagy activator rapamycin, whereas these were exacerbated by the autophagy inhibitor 3-methyladenine, indicating that instead of inducing SGN death, autophagy played a neuroprotective role in SGNs treated with cisplatin both in vitro and in vivo. We further demonstrated that autophagy attenuated reactive oxygen species (ROS) accumulation and alleviated cisplatin-induced oxidative stress in SGNs to mediate its protective effects. Notably, the role of the antioxidant enzyme PRDX1 (peroxiredoxin 1) in modulating autophagy in SGNs was first identified. Deficiency in PRDX1 suppressed autophagy and increased SGN loss after cisplatin exposure, while upregulating PRDX1 pharmacologically or by adeno-associated virus activated autophagy and thus inhibited ROS accumulation and apoptosis and attenuated SGN loss induced by cisplatin. Finally, we showed that the underlying mechanism through which PRDX1 triggers autophagy in SGNs was, at least partially, through activation of the PTEN-AKT signaling pathway. These findings suggest potential therapeutic targets for the amelioration of drug-induced SNHL through autophagy activation. Abbreviations: 3-MA: 3-methyladenine; AAV : adeno-associated virus; ABR: auditory brainstem responses; AKT/protein kinase B: thymoma viral proto-oncogene; Baf: bafilomycin A1; CAP: compound action potential; COX4I1: cytochrome c oxidase subunit 4I1; Cys: cysteine; ER: endoplasmic reticulum; H2O2: hydrogen peroxide; HC: hair cell; MAP1LC3B/LC3B: microtubule-associated protein 1 light chain 3 beta; NAC: N-acetylcysteine; PRDX1: peroxiredoxin 1; PTEN: phosphatase and tensin homolog; RAP: rapamycin; ROS: reactive oxygen species; SGNs: spiral ganglion neurons; SNHL: sensorineural hearing loss; SQSTM1/p62: sequestosome 1; TOMM20: translocase of outer mitochondrial membrane 20; TUNEL: terminal deoxynucleotidyl transferase-mediated dUTP nick-end-labeling; WT: wild type.
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Affiliation(s)
- Wenwen Liu
- Department of Otolaryngology-Head and Neck Surgery, Shandong Provincial ENT Hospital, Cheeloo College of Medicine, Shandong University, Jinan, China
| | - Lei Xu
- Department of Otolaryngology-Head and Neck Surgery, Shandong Provincial ENT Hospital, Cheeloo College of Medicine, Shandong University, Jinan, China
| | - Xue Wang
- Department of Otolaryngology-Head and Neck Surgery, Shandong Provincial ENT Hospital, Cheeloo College of Medicine, Shandong University, Jinan, China
| | - Daogong Zhang
- Department of Otolaryngology-Head and Neck Surgery, Shandong Provincial ENT Hospital, Cheeloo College of Medicine, Shandong University, Jinan, China
| | - Gaoying Sun
- Department of Otolaryngology-Head and Neck Surgery, Shandong Provincial ENT Hospital, Cheeloo College of Medicine, Shandong University, Jinan, China
| | - Man Wang
- Department of Otolaryngology-Head and Neck Surgery, Shandong Provincial ENT Hospital, Cheeloo College of Medicine, Shandong University, Jinan, China
| | - Mingming Wang
- Department of Otolaryngology-Head and Neck Surgery, Shandong Provincial ENT Hospital, Cheeloo College of Medicine, Shandong University, Jinan, China
| | - Yuechen Han
- Department of Otolaryngology-Head and Neck Surgery, Shandong Provincial ENT Hospital, Cheeloo College of Medicine, Shandong University, Jinan, China
| | - Renjie Chai
- State Key Laboratory of Bioelectronics, School of Life Sciences and Technology, Jiangsu Province High-Tech Key Laboratory for Bio-Medical Research, Southeast University, Nanjing, China.,Co-Innovation Center of Neuroregeneration, Nantong University, Nantong, China.,Institute for Stem Cell and Regeneration, Chinese Academy of Science, Beijing, China.,Beijing Key Laboratory of Neural Regeneration and Repair, Capital Medical University, Beijing, China
| | - Haibo Wang
- Department of Otolaryngology-Head and Neck Surgery, Shandong Provincial ENT Hospital, Cheeloo College of Medicine, Shandong University, Jinan, China
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Su Y, Yang LM, Ornitz DM. FGF20-FGFR1 signaling through MAPK and PI3K controls sensory progenitor differentiation in the organ of Corti. Dev Dyn 2021; 250:134-144. [PMID: 32735383 PMCID: PMC8415122 DOI: 10.1002/dvdy.231] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2020] [Revised: 07/27/2020] [Accepted: 07/28/2020] [Indexed: 12/11/2022] Open
Abstract
BACKGROUND Fibroblast Growth Factor 20 (FGF20)-FGF receptor 1 (FGFR1) signaling is essential for cochlear hair cell (HC) and supporting cell (SC) differentiation. In other organ systems, FGFR1 signals through several intracellular pathways including MAPK (ERK), PI3K, phospholipase C ɣ (PLCɣ), and p38. Previous studies implicated MAPK and PI3K pathways in HC and SC development. We hypothesized that one or both would be important downstream mediators of FGF20-FGFR1 signaling for HC differentiation. RESULTS By inhibiting pathways downstream of FGFR1 in cochlea explant cultures, we established that both MAPK and PI3K pathways are required for HC differentiation while PLCɣ and p38 pathways are not. Examining the canonical PI3K pathway, we found that while AKT is necessary for HC differentiation, it is not sufficient to rescue the Fgf20-/- phenotype. To determine whether PI3K functions downstream of FGF20, we inhibited Phosphatase and Tensin Homolog (PTEN) in Fgf20-/- explants. Overactivation of PI3K resulted in a partial rescue of the Fgf20-/- phenotype, demonstrating a requirement for PI3K downstream of FGF20. Consistent with a requirement for the MAPK pathway for FGF20-regulated HC differentiation, we show that treating Fgf20-/- explants with FGF9 increased levels of dpERK. CONCLUSIONS Together, these data provide evidence that both MAPK and PI3K are important downstream mediators of FGF20-FGFR1 signaling during HC and SC differentiation.
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Affiliation(s)
- Yutao Su
- Department of Developmental Biology, Washington University School of Medicine, St. Louis, Missouri, USA
| | - Lu M Yang
- Department of Developmental Biology, Washington University School of Medicine, St. Louis, Missouri, USA
| | - David M Ornitz
- Department of Developmental Biology, Washington University School of Medicine, St. Louis, Missouri, USA
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Jadali A, Kwan KY. Activation of PI3K signaling prevents aminoglycoside-induced hair cell death in the murine cochlea. Biol Open 2016; 5:698-708. [PMID: 27142333 PMCID: PMC4920183 DOI: 10.1242/bio.016758] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2016] [Accepted: 04/17/2016] [Indexed: 12/28/2022] Open
Abstract
Loss of sensory hair cells of the inner ear due to aminoglycoside exposure is a major cause of hearing loss. Using an immortalized multipotent otic progenitor (iMOP) cell line, specific signaling pathways that promote otic cell survival were identified. Of the signaling pathways identified, the PI3K pathway emerged as a strong candidate for promoting hair cell survival. In aging animals, components for active PI3K signaling are present but decrease in hair cells. In this study, we determined whether activated PI3K signaling in hair cells promotes survival. To activate PI3K signaling in hair cells, we used a small molecule inhibitor of PTEN or genetically ablated PTEN using a conditional knockout animal. Hair cell survival was challenged by addition of gentamicin to cochlear cultures. Hair cells with activated PI3K signaling were more resistant to aminoglycoside-induced hair cell death. These results indicate that increased PI3K signaling in hair cells promote survival and the PI3K signaling pathway is a target for preventing aminoglycoside-induced hearing loss.
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Affiliation(s)
- Azadeh Jadali
- Department of Cell Biology and Neuroscience, Rutgers University, Piscataway, NJ 08854, USA Stem Cell Research Center and Keck Center for Collaborative Neuroscience, Rutgers University, Piscataway, NJ 08854, USA
| | - Kelvin Y Kwan
- Department of Cell Biology and Neuroscience, Rutgers University, Piscataway, NJ 08854, USA Stem Cell Research Center and Keck Center for Collaborative Neuroscience, Rutgers University, Piscataway, NJ 08854, USA
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PTEN regulation of the proliferation and differentiation of auditory progenitors through the PTEN/PI3K/Akt-signaling pathway in mice. Neuroreport 2014; 25:177-83. [PMID: 24481416 PMCID: PMC3906289 DOI: 10.1097/wnr.0000000000000069] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Supplemental Digital Content is available in the text. The organ of Corti, which is the sensory organ of hearing, consists of a single row of inner hair cells and three rows of outer hair cells in mice. The auditory hair cells develop from auditory progenitors. Hair cell development is related to several genes, including PTEN. Homozygous null mutant (PTEN−/−) mice die at around embryonic day 9, when hair cells are extremely immature. Moreover, in heterozygous PTEN knockout mice, it was found that PTEN regulates the proliferation of auditory progenitors. However, little is known about the molecular mechanism underlying this regulation. In the present study, we generated PTEN conditional knockout in the inner ear of mice and studied the aforementioned molecular mechanisms. Our results showed that PTEN knockout resulted in supernumerary hair cells, increased p-Akt level, and decreased p27kip1 level. Furthermore, the presence of supernumerary hair cells could be explained by the delayed withdrawal of auditory progenitors from the cell cycle. The increased p-Akt level correlates with p27kip1 downregulation in the cochlea in the Pax2-PTEN−/− mice. The reduced p27kip1 could not maintain the auditory progenitors in the nonproliferative state and some progenitors continued to divide. Consequently, additional progenitors differentiated into supernumerary hair cells. We suggest that PTEN regulates p27kip1 through p-Akt, thereby regulating the proliferation and differentiation of auditory progenitors.
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7
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The expression of PTEN in the development of mouse cochlear lateral wall. Neuroscience 2014; 258:263-9. [DOI: 10.1016/j.neuroscience.2013.11.017] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2013] [Revised: 11/07/2013] [Accepted: 11/07/2013] [Indexed: 12/20/2022]
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Coupling the cell cycle to development and regeneration of the inner ear. Semin Cell Dev Biol 2013; 24:507-13. [PMID: 23665151 DOI: 10.1016/j.semcdb.2013.04.004] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2013] [Accepted: 04/23/2013] [Indexed: 12/19/2022]
Abstract
Cell cycle exit and acquirement of a postmitotic state is essential for the proper development of organs. In the present review, we examine the role of the cell cycle control in the sensory epithelia of the mammalian inner ear. We describe the roles of the core cell cycle regulators in the proliferation of prosensory cells and in the initiation and maintenance of terminal mitosis of the sensory epithelia. We also discuss how other intracellular signalling may influence the cell cycle. Finally, we address the question of whether manipulations of the cell cycle may have the potential to create replacement cells for the damaged inner sensory epithelia.
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Kim HJ, Woo HM, Ryu J, Bok J, Kim JW, Choi SB, Park MH, Park HY, Koo SK. Conditional deletion of pten leads to defects in nerve innervation and neuronal survival in inner ear development. PLoS One 2013; 8:e55609. [PMID: 23393595 PMCID: PMC3564925 DOI: 10.1371/journal.pone.0055609] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2012] [Accepted: 01/02/2013] [Indexed: 12/25/2022] Open
Abstract
All cellular phenomena and developmental events, including inner ear development, are modulated through harmonized signaling networks. Phosphatase and tensin homolog deleted on chromosome 10 (PTEN), a tumor suppressor, is a major signaling component involved in cross talk with key regulators of development; i.e., Wnt, Notch, and bone morphogenetic proteins. Although Pten function has been studied in various systems, its role in inner ear development is poorly understood. Here, we used inner ear-specific Pten conditional knockout mice and examined the characteristics of the inner ear. In a detailed analysis of the phenotype, reduced cochlear turning and widened epithelia were observed. Phalloidin staining of sensory epithelium revealed that hair cell patterns were disturbed; i.e., additional rows of hair cells were discovered. The neural abnormality revealed a reduction in and disorganization of nerve fibers, including apoptosis at the neural precursor stage. Pten deficiency induced increased phosphorylation of Akt at Ser473. The elevation of inhibitory glycogen synthase kinase 3β Ser9 phosphorylation (pGSK3β) was sustained until the neuronal differentiation stage at embryonic day 14.5, instead of pGSK3β downregulation. This is the first report on the influence of Pten/Akt/GSK3β signaling on the development of spiral ganglia. These results suggest that Pten is required for the maintenance of neuroblast number, neural precursors, and differentiation in the inner ear.
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Affiliation(s)
- Hyung Jin Kim
- Center for Biomedical Sciences, National Institute of Health, Osong Health Technology Administration Complex 643, Yeonje-ri, Osong-eup, Cheongwon-gun, Chungcheongbuk-do, South Korea
| | - Hae-Mi Woo
- Center for Biomedical Sciences, National Institute of Health, Osong Health Technology Administration Complex 643, Yeonje-ri, Osong-eup, Cheongwon-gun, Chungcheongbuk-do, South Korea
| | - Jihee Ryu
- Center for Biomedical Sciences, National Institute of Health, Osong Health Technology Administration Complex 643, Yeonje-ri, Osong-eup, Cheongwon-gun, Chungcheongbuk-do, South Korea
| | - Jinwoong Bok
- Department of Anatomy, BK21 Project for Medical Science, Yonsei University College of Medicine, Seoul, South Korea
| | - Jin Woo Kim
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology (KAIST), 291 Daehak-ro, Yuseong-gu, Daejeon, South Korea
| | - Sang Back Choi
- Center for Biomedical Sciences, National Institute of Health, Osong Health Technology Administration Complex 643, Yeonje-ri, Osong-eup, Cheongwon-gun, Chungcheongbuk-do, South Korea
| | - Mi-Hyun Park
- Center for Biomedical Sciences, National Institute of Health, Osong Health Technology Administration Complex 643, Yeonje-ri, Osong-eup, Cheongwon-gun, Chungcheongbuk-do, South Korea
| | - Hyun-Young Park
- Center for Biomedical Sciences, National Institute of Health, Osong Health Technology Administration Complex 643, Yeonje-ri, Osong-eup, Cheongwon-gun, Chungcheongbuk-do, South Korea
| | - Soo Kyung Koo
- Center for Biomedical Sciences, National Institute of Health, Osong Health Technology Administration Complex 643, Yeonje-ri, Osong-eup, Cheongwon-gun, Chungcheongbuk-do, South Korea
- * E-mail:
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Postnatal development, maturation and aging in the mouse cochlea and their effects on hair cell regeneration. Hear Res 2012; 297:68-83. [PMID: 23164734 DOI: 10.1016/j.heares.2012.11.009] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/03/2012] [Revised: 10/22/2012] [Accepted: 11/07/2012] [Indexed: 12/23/2022]
Abstract
The organ of Corti in the mammalian inner ear is comprised of mechanosensory hair cells (HCs) and nonsensory supporting cells (SCs), both of which are believed to be terminally post-mitotic beyond late embryonic ages. Consequently, regeneration of HCs and SCs does not occur naturally in the adult mammalian cochlea, though recent evidence suggests that these cells may not be completely or irreversibly quiescent at earlier postnatal ages. Furthermore, regenerative processes can be induced by genetic and pharmacological manipulations, but, more and more reports suggest that regenerative potential declines as the organ of Corti continues to age. In numerous mammalian systems, such effects of aging on regenerative potential are well established. However, in the cochlea, the problem of regeneration has not been traditionally viewed as one of aging. This is an important consideration as current models are unable to elicit widespread regeneration or full recovery of function at adult ages yet regenerative therapies will need to be developed specifically for adult populations. Still, the advent of gene targeting and other genetic manipulations has established mice as critically important models for the study of cochlear development and HC regeneration and suggests that auditory HC regeneration in adult mammals may indeed be possible. Thus, this review will focus on the pursuit of regeneration in the postnatal and adult mouse cochlea and highlight processes that occur during postnatal development, maturation, and aging that could contribute to an age-related decline in regenerative potential. Second, we will draw upon the wealth of knowledge pertaining to age related senescence in tissues outside of the ear to synthesize new insights and potentially guide future research aimed at promoting HC regeneration in the adult cochlea.
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Dong Y, Sui L, Yamaguchi F, Kamitori K, Hirata Y, Hossain MA, Suzuki A, Holley MC, Tokuda M. Phosphatase and tensin homolog deleted on chromosome 10 regulates sensory cell proliferation and differentiation of hair bundles in the mammalian cochlea. Neuroscience 2010; 170:1304-13. [PMID: 20727948 DOI: 10.1016/j.neuroscience.2010.08.024] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2010] [Revised: 08/05/2010] [Accepted: 08/12/2010] [Indexed: 01/16/2023]
Abstract
Phosphatase and tensin homolog deleted on chromosome 10 (PTEN) is a tumor suppressor gene that regulates cell proliferation, differentiation and growth. It regulates neural and glioma stem/progenitor cell renewal and PTEN deletion can drive expansion of epithelial progenitors in the lung, enhancing their capacity for regeneration. Because it is expressed at relatively high levels in developing mammalian auditory hair cells we have analyzed the phenotype of the auditory epithelium in PTEN knock-out mice. PTEN(+/-) heterozygous littermates have only one functional copy of the gene and show clear evidence for haploinsufficiency in the organ of Corti. Auditory sensory epithelial progenitors withdraw from the cell cycle later than in wild-type animals and this is associated with increases in the numbers of both inner and outer hair cells. The cytoskeletal differentiation of hair cells was also affected. While many hair bundles on the hair cells appeared to develop normally, others were structurally disorganized and a number were missing, apparently lost after they had been formed. The results show that PTEN plays a novel role in regulating cell proliferation and differentiation of hair bundles in auditory sensory epithelial cells and suggest that PTEN signaling pathways may provide therapeutic targets for auditory sensory regeneration.
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Affiliation(s)
- Y Dong
- Department of Cell Physiology, Faculty of Medicine, Kagawa University, 1750-1 Ikenobe, Miki-cho, Kita-gun, Kagawa 761-0793, Japan.
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