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Liu J, Chen H, Lin X, Zhu X, Huang J, Xu W, Tan M, Su J. Melatonin Suppresses Cyclic GMP-AMP Synthase-Stimulator of Interferon Genes Signaling and Delays the Development of Hearing Loss in the C57BL/6J Presbycusis Mouse Model. Neuroscience 2023; 517:84-95. [PMID: 36702373 DOI: 10.1016/j.neuroscience.2023.01.015] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2022] [Revised: 01/05/2023] [Accepted: 01/16/2023] [Indexed: 01/24/2023]
Abstract
Melatonin supplementation has been shown to delay age-related hearing loss (ARHL) progression. Previously, melatonin was found to inhibit neuronal mitochondrial DNA (mtDNA) release, as well as inhibit cyclic GMP-AMP synthase (cGAS)-stimulator of interferon genes (STING) signaling, thereby delaying the onset of central nervous system diseases. Therefore, we hypothesized that melatonin may delay the progression of hearing loss in the C57BL/6J presbycusis mouse model by inhibiting cGAS-STING signaling in the auditory pathway. Oral melatonin at 10 mg/kg/d was administered to 3-month-old C57BL/6J mice until 12 months of age. The auditory brainstem response (ABR) threshold was used to assess their hearing ability. By real-time polymerase chain reaction and Western blot analysis, the levels of cytosolic mtDNA, cGAS/STING, and cytokines were examined in the mouse cochlea, inferior colliculus, and auditory cortex. We found that the 12-month-old control mice exhibited significant hearing loss, increased cytosolic mtDNA, increased expression of inflammatory factors TNF-α, IL-6, IFN-β, Cxcl10, and Ifit3, up-regulated cGAS and STING expression, and enhanced interferon regulatory factor 3 (IRF3) phosphorylation in the C57BL/6J mouse cochlea, inferior colliculus, and auditory cortex. Melatonin treatment significantly improved hearing, decreased cytosolic mtDNA, suppressed the expression of inflammatory cytokines TNF-α, IL-6, IFN-β, Ifit3, and Cxcl10, down-regulated cGAS and STING expression, and attenuated IRF3 phosphorylation in the C57BL/6J mouse cochlea, inferior colliculus, and auditory cortex. This study suggested that melatonin had a protective effect on auditory function in the C57BL/6J presbycusis mouse model, which may be mediated through reducing mtDNA release, inhibiting the cGAS-STING signaling pathway in the auditory pathway.
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Affiliation(s)
- Jinlan Liu
- Department of Otolaryngology-Head & Neck Surgery, First Afliated Hospital of Guangxi Medical University, Nanning, Guangxi, China; Department of Otolaryngology-Head & Neck Surgery, Guangxi International Zhuang Medicine Hospital, Nanning, Guangxi, China
| | - Huiying Chen
- Department of Otolaryngology-Head & Neck Surgery, First Afliated Hospital of Guangxi Medical University, Nanning, Guangxi, China
| | - Xiaoyu Lin
- Department of Otolaryngology-Head & Neck Surgery, First Afliated Hospital of Guangxi Medical University, Nanning, Guangxi, China
| | - Xiaoting Zhu
- Department of Otolaryngology-Head & Neck Surgery, First Afliated Hospital of Guangxi Medical University, Nanning, Guangxi, China
| | - Jialin Huang
- Department of Otolaryngology-Head & Neck Surgery, First Afliated Hospital of Guangxi Medical University, Nanning, Guangxi, China
| | - Wenfeng Xu
- Department of Otolaryngology-Head & Neck Surgery, First Afliated Hospital of Guangxi Medical University, Nanning, Guangxi, China
| | - Ming Tan
- Department of Otolaryngology-Head & Neck Surgery, First Afliated Hospital of Guangxi Medical University, Nanning, Guangxi, China
| | - Jiping Su
- Department of Otolaryngology-Head & Neck Surgery, First Afliated Hospital of Guangxi Medical University, Nanning, Guangxi, China.
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Fan J, Wang S, Lu X, Sun Z. Transplantation of bone marrow cells from miR150 knockout mice improves senescence-associated humoral immune dysfunction and arterial stiffness. Metabolism 2022; 134:155249. [PMID: 35792174 PMCID: PMC9796492 DOI: 10.1016/j.metabol.2022.155249] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/17/2021] [Revised: 06/06/2022] [Accepted: 06/24/2022] [Indexed: 12/30/2022]
Abstract
BACKGROUND AND PURPOSE The senescence-accelerated mouse P1 (SAMP1) suffers from humoral immune deficiency, arterial stiffness and accelerated aging. In contrast, the microRNA-150 knockout (miR-150-KO) mice show enhanced humoral immune function including increased B cell population and elevated serum immunoglobulin levels and enjoy extended lifespan. The purpose of this study was to investigate whether transplantation of bone marrow cells (BMCs) from miR-150-KO mice affects immune deficiency and arterial stiffening in SAMP1 mice. METHODS AND RESULTS Pulse wave velocity and blood pressure were increased significantly in SAMP1 mice (10 months), indicating arterial stiffening and hypertension. Interestingly, transplantation of BMCs from miR-150-KO mice significantly attenuated arterial stiffening and hypertension in SAMP1 mice within eight weeks. BMC transplantation from miR-150-KO mice partially rescued the downregulation of B lymphocytes, largely restored serum IgG and IgM levels, decreased inflammatory cytokine and chemokine expression, and attenuated macrophage and T cell infiltration in aortas in SAMP1 mice. BMC transplantation nearly abolished the upregulation of collagen 1, TGFβ1, Scleraxis, MMP-2 and MMP-9 expression and the downregulation of elastin levels in aortas in SAMP1 mice. FISH staining confirmed existence of the transplanted BMCs at end of the experiment. In cultured endothelial cells, IgG-deficient medium invoked upregulation of inflammatory cytokine/chemokine expression which can be rescued by treatment with IgG. CONCLUSIONS Accelerated senescence caused arterial stiffening via impairing the humoral immune function in SAMP1 mice. BMC transplantation from miR-150-KO mice attenuated arterial matrix remodeling and stiffening and hypertension in SAMP1 mice partly via improving the humoral immune function which attenuates vascular inflammation.
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Affiliation(s)
- Jun Fan
- Department of Physiology, College of Medicine, University of Oklahoma Health Science Center, Oklahoma City, OK 73034, USA
| | - Shirley Wang
- Department of Physiology, College of Medicine, University of Oklahoma Health Science Center, Oklahoma City, OK 73034, USA
| | - Xianglan Lu
- Department of Physiology, College of Medicine, University of Oklahoma Health Science Center, Oklahoma City, OK 73034, USA
| | - Zhongjie Sun
- Department of Physiology, College of Medicine, University of Tennessee Health Science Center, Memphis, TN 38163, USA; Department of Physiology, College of Medicine, University of Oklahoma Health Science Center, Oklahoma City, OK 73034, USA.
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Fan J, Wang S, Chen K, Sun Z. Aging impairs arterial compliance via Klotho-mediated downregulation of B-cell population and IgG levels. Cell Mol Life Sci 2022; 79:494. [PMID: 36001158 PMCID: PMC10082671 DOI: 10.1007/s00018-022-04512-x] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2022] [Revised: 07/31/2022] [Accepted: 08/01/2022] [Indexed: 11/27/2022]
Abstract
OBJECTIVE Aging is associated with compromised immune function and arterial remodeling and stiffness. The purpose of this study is to investigate whether in vivo AAV-based delivery of secreted Klotho (SKL) gene (AAV-SKL) improves aging- and senescence-associated immune dysfunction and arterial stiffness. METHODS AND RESULTS Senescence-accelerated mice prone strain 1 (SAMP1, 10 months) and old mice (20 months) were used. Serum SKL levels, B-cell population and serum IgG levels were markedly decreased in SAMP1 and old mice. Rescue of downregulation of serum SKL levels by in vivo AAV2-based delivery of SKL gene (AAV-SKL) increased B-cell population and serum IgG levels and attenuated arterial stiffness in SAMP1 and old mice. Thus, Klotho deficiency may play a role in senescence- and aging-associated humoral immune dysfunction and arterial stiffness. Vascular infiltration of inflammatory cells and expression of TGFβ1, collagen 1, scleraxis, MMP-2 and MMP-9 were increased while the elastin level was decreased in aortas of SAMP1 and old mice which can be rescued by AAV-SKL. Interestingly, treatment with IgG effectively rescued arterial inflammation and remodeling and attenuated arterial stiffness and hypertension in aging mice. In cultured B-lymphoblast cells, we further showed that SKL regulates B-cell proliferation and maturation partly via the NFkB pathway. CONCLUSION Aging-associated arterial stiffening may be largely attributed to downregulation of B-cell population and serum IgG levels. AAV-SKL attenuates arterial stiffness in aging mice partly via restoring B-cell population and serum IgG levels which attenuates aging-associated vascular inflammation and arterial remodeling.
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Affiliation(s)
- Jun Fan
- Department of Physiology, College of Medicine, University of Oklahoma Health Science Center, Oklahoma City, OK, USA
| | - Shirley Wang
- Department of Physiology, College of Medicine, University of Oklahoma Health Science Center, Oklahoma City, OK, USA
| | - Kai Chen
- Department of Physiology, College of Medicine, University of Oklahoma Health Science Center, Oklahoma City, OK, USA
- Department of Physiology, College of Medicine, University of Tennessee Health Science Center, A302 Coleman Building, 956 Court Avenue, Memphis, TN, 38163, USA
| | - Zhongjie Sun
- Department of Physiology, College of Medicine, University of Oklahoma Health Science Center, Oklahoma City, OK, USA.
- Department of Physiology, College of Medicine, University of Tennessee Health Science Center, A302 Coleman Building, 956 Court Avenue, Memphis, TN, 38163, USA.
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Zhang Y, Li Y, Fu X, Wang P, Wang Q, Meng W, Wang T, Yang J, Chai R. The Detrimental and Beneficial Functions of Macrophages After Cochlear Injury. Front Cell Dev Biol 2021; 9:631904. [PMID: 34458249 PMCID: PMC8385413 DOI: 10.3389/fcell.2021.631904] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2020] [Accepted: 07/14/2021] [Indexed: 12/20/2022] Open
Abstract
Macrophages are the main intrinsic immune cells in the cochlea; they can be activated and play a complicated role after cochlear injury. Many studies have shown that the number of macrophages and their morphological characteristics within the major cochlear partitions undergo significant changes under various pathological conditions including acoustic trauma, ototoxic drug treatment, age-related cochlear degeneration, selective hair cell (HC) and spiral ganglion neuron (SGN) elimination, and surgery. However, the exact role of these macrophages after cochlear injury is still unclear. Regulating the migration and activity of macrophages may be a therapeutic approach to reduce the risk or magnitude of trauma-induced hearing loss, and this review highlights the role of macrophages on the peripheral auditory structures of the cochlea and elucidate the mechanisms of macrophage injury and the strategies to reduce the injury by regulating macrophage.
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Affiliation(s)
- Yuan Zhang
- MOE Key Laboratory for Developmental Genes and Human Disease, Jiangsu Province High-Tech Key Laboratory for Bio-Medical Research, School of Life Sciences and Technology, Southeast University, Nanjing, China.,Department of Otolaryngology Head and Neck, Nanjing Tongren Hospital, School of Medicine, Southeast University, Nanjing, China.,Co-innovation Center of Neuroregeneration, Nantong University, Nantong, China
| | - Yiyuan Li
- MOE Key Laboratory for Developmental Genes and Human Disease, Jiangsu Province High-Tech Key Laboratory for Bio-Medical Research, School of Life Sciences and Technology, Southeast University, Nanjing, China
| | - Xiaolong Fu
- MOE Key Laboratory for Developmental Genes and Human Disease, Jiangsu Province High-Tech Key Laboratory for Bio-Medical Research, School of Life Sciences and Technology, Southeast University, Nanjing, China
| | - Pengjun Wang
- Department of Otorhinolaryngology, Affiliated Sixth People's Hospital of Shanghai Jiao Tong University, Shanghai, China
| | - Qin Wang
- Department of Otolaryngology-Head and Neck Surgery, The Second Xiangya Hospital, Central South University, Changsha, China
| | - Wei Meng
- Department of Otolaryngology Head and Neck, Nanjing Tongren Hospital, School of Medicine, Southeast University, Nanjing, China
| | - Tian Wang
- Department of Otolaryngology-Head and Neck Surgery, The Second Xiangya Hospital, Central South University, Changsha, China
| | - Jianming Yang
- Department of Otorhinolaryngology, The Second Affiliated Hospital of Anhui Medical University, Hefei, China
| | - Renjie Chai
- MOE Key Laboratory for Developmental Genes and Human Disease, Jiangsu Province High-Tech Key Laboratory for Bio-Medical Research, School of Life Sciences and Technology, Southeast University, Nanjing, China.,Co-innovation Center of Neuroregeneration, Nantong University, Nantong, China.,Institute for Stem Cell and Regeneration, Chinese Academy of Sciences, Beijing, China
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A Genome-Wide Association Study of Age-Related Hearing Impairment in Middle- and Old-Aged Chinese Twins. BIOMED RESEARCH INTERNATIONAL 2021; 2021:3629624. [PMID: 34337005 PMCID: PMC8314043 DOI: 10.1155/2021/3629624] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/23/2020] [Revised: 06/17/2021] [Accepted: 07/03/2021] [Indexed: 11/17/2022]
Abstract
Background Age-related hearing impairment (ARHI) is considered an unpreventable disorder. We aimed to detect specific genetic variants that are potentially related to ARHI via genome-wide association study (GWAS). Methods A sample of 131 dizygotic twins was genotyped for single-nucleotide polymorphism- (SNP-) based GWAS. Gene-based test was performed using VEGAS2. Pathway enrichment analysis was conducted by PASCAL. Results The twins are with a median age of 49 years, of which 128 were females and 134 were males. rs6633657 was the only SNP that reached the genome-wide significance level for better ear hearing level (BEHL) at 2.0 kHz (P = 1.19 × 10-8). Totally, 9, 10, 42, 7, 17, and 5 SNPs were suggestive evidence level for (P < 1 × 10-5) BEHLs at 0.5, 1.0, 2.0, 4.0, and 8.0 kHz and pure tone average (PTA), respectively. Several promising genetic regions in chromosomes (near the C20orf196, AQPEP, UBQLN3, OR51B5, OR51I2, OR52D1, GLTP, GIT2, and PARK2) nominally associated with ARHI were identified. Gene-based analysis revealed 165, 173, 77, 178, 170, and 145 genes nominally associated with BEHLs at 0.5, 1.0, 2.0, 4.0, and 8.0 kHz and PTA, respectively (P < 0.05). For BEHLs at 0.5, 1.0, and 2.0 kHz, the main enriched pathways were phosphatidylinositol signaling system, regulation of ornithine decarboxylase, eukaryotic translation initiation factor (EIF) pathway, amine compound solute carrier (SLC) transporters, synthesis of phosphoinositides (PIPS) at the plasma membrane, and phosphatidylinositols (PI) metabolism. Conclusions The genetic variations reported herein are significantly involved in functional genes and regulatory domains that mediate ARHI pathogenesis. These findings provide clues for the further unraveling of the molecular physiology of hearing functions and identifying novel diagnostic biomarkers and therapeutic targets of ARHI.
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Iwai H, Inaba M, Van Bui D, Suzuki K, Sakagami T, Yun Y, Mitani A, Kobayashi Y, Kanda A. Treg and IL-1 receptor type 2-expressing CD4 + T cell-deleted CD4 + T cell fraction prevents the progression of age-related hearing loss in a mouse model. J Neuroimmunol 2021; 357:577628. [PMID: 34130076 DOI: 10.1016/j.jneuroim.2021.577628] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2021] [Revised: 05/11/2021] [Accepted: 06/05/2021] [Indexed: 11/28/2022]
Abstract
We investigated the association between cellular immunity and age-related hearing loss (ARHL) development using three CD4+ T cell fractions, namely, naturally occurring regulatory T cells (Treg), interleukin 1 receptor type 2-expressing T cells (I1R2), and non-Treg non-I1R2 (nTnI) cells, which comprised Treg and I1R2-deleted CD4+ T cells. Inoculation of the nTnI fraction into a ARHL murine model, not only prevented the development of ARHL and the degeneration of spiral ganglion neurons, but also suppressed serum nitric oxide, a source of oxidative stress. Further investigations on CD4+ T cell fractions could provide novel insights into the prevention of aging, including presbycusis.
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Affiliation(s)
- Hiroshi Iwai
- Department of Otolaryngology, Head and Neck Surgery, Kansai Medical University, Hirakata, Osaka, Japan.
| | - Muneo Inaba
- First Department of Medicine, Kansai Medical University, Osaka, Japan
| | - Dan Van Bui
- Department of Otolaryngology, Head and Neck Surgery, Kansai Medical University, Hirakata, Osaka, Japan
| | - Kensuke Suzuki
- Department of Otolaryngology, Head and Neck Surgery, Kansai Medical University, Hirakata, Osaka, Japan
| | - Tomofumi Sakagami
- Department of Otolaryngology, Head and Neck Surgery, Kansai Medical University, Hirakata, Osaka, Japan
| | - Yasutaka Yun
- Department of Otolaryngology, Head and Neck Surgery, Kansai Medical University, Hirakata, Osaka, Japan
| | - Akitoshi Mitani
- Department of Otolaryngology, Head and Neck Surgery, Kansai Medical University, Hirakata, Osaka, Japan
| | - Yoshiki Kobayashi
- Department of Otolaryngology, Head and Neck Surgery, Kansai Medical University, Hirakata, Osaka, Japan
| | - Akira Kanda
- Department of Otolaryngology, Head and Neck Surgery, Kansai Medical University, Hirakata, Osaka, Japan
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7
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Chai Y, He W, Yang W, Hetrick AP, Gonzalez JG, Sargsyan L, Wu H, Jung TTK, Li H. Intratympanic Lipopolysaccharide Elevates Systemic Fluorescent Gentamicin Uptake in the Cochlea. Laryngoscope 2021; 131:E2573-E2582. [PMID: 33956344 PMCID: PMC8453712 DOI: 10.1002/lary.29610] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2020] [Revised: 04/09/2021] [Accepted: 04/26/2021] [Indexed: 12/20/2022]
Abstract
Objectives/Hypothesis Lipopolysaccharide (LPS), a key component of bacterial endotoxins, activates macrophages and triggers the release of inflammatory cytokines in mammalian tissues. Recent studies have shown that intratympanic injection of LPS simulates acute otitis media (AOM) and results in morphological and functional changes in the inner ear. Here we established an AOM mouse model with LPS to investigate the uptake of ototoxic gentamicin in the inner ear, and elucidated the underlying mechanism by focusing on cochlear inflammation as a result of AOM. Study Design Preclinical rodent animal model. Methods Fluorescently tagged gentamicin (GTTR) was systemically administered to mice with AOM. Iba1‐positive macrophage morphology and inner ear cytokine profile were evaluated by immunofluorescence technique and a mouse cytokine array kit, respectively. Results We observed characteristic symptoms of AOM in the LPS‐treated ears with elevated hearing thresholds indicating a conductive hearing loss. More importantly, the LPS‐induced AOM activated cochlear inflammatory responses, manifested by macrophage infiltration, particularly in the organ of Corti and the spiral ligament, in addition to the up‐regulation of proinflammatory cytokines. Meanwhile, GTTR uptake in the stria vascularis and sensory hair cells from all the LPS‐treated ears was significantly enhanced at 24, 48, and 72‐hour post‐treatment, as the most prominent enhancement was observed in the 48‐hour group. Conclusion In summary, this study suggests that the pathological cochlea is more susceptible to ototoxic drugs, including aminoglycosides, and justified the clinical concern of aminoglycoside ototoxicity in the AOM treatment. Laryngoscope, 131:E2573–E2582, 2021
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Affiliation(s)
- Yongchuan Chai
- Research Service, VA Loma Linda Healthcare System, Loma Linda, California, U.S.A.,Department of Otolaryngology Head and Neck Surgery, Shanghai Ninth People's Hospital Affiliated Shanghai Jiaotong University School of Medicine, Shanghai, China.,Ear Institute, Shanghai Jiaotong University School of Medicine, Shanghai, China.,Department of Otolaryngology Head and Neck Surgery, Loma Linda University Health, Loma Linda, California, U.S.A
| | - Weiwei He
- Research Service, VA Loma Linda Healthcare System, Loma Linda, California, U.S.A.,Department of Otolaryngology Head and Neck Surgery, Shanghai Ninth People's Hospital Affiliated Shanghai Jiaotong University School of Medicine, Shanghai, China.,Ear Institute, Shanghai Jiaotong University School of Medicine, Shanghai, China.,Department of Otolaryngology Head and Neck Surgery, Loma Linda University Health, Loma Linda, California, U.S.A
| | - Weiqiang Yang
- Research Service, VA Loma Linda Healthcare System, Loma Linda, California, U.S.A.,Department of Otolaryngology Head and Neck Surgery, Loma Linda University Health, Loma Linda, California, U.S.A
| | - Alisa P Hetrick
- Research Service, VA Loma Linda Healthcare System, Loma Linda, California, U.S.A
| | - Jessica G Gonzalez
- Research Service, VA Loma Linda Healthcare System, Loma Linda, California, U.S.A
| | - Liana Sargsyan
- Research Service, VA Loma Linda Healthcare System, Loma Linda, California, U.S.A
| | - Hao Wu
- Department of Otolaryngology Head and Neck Surgery, Shanghai Ninth People's Hospital Affiliated Shanghai Jiaotong University School of Medicine, Shanghai, China.,Ear Institute, Shanghai Jiaotong University School of Medicine, Shanghai, China
| | - Timothy T K Jung
- Research Service, VA Loma Linda Healthcare System, Loma Linda, California, U.S.A.,Department of Otolaryngology Head and Neck Surgery, Loma Linda University Health, Loma Linda, California, U.S.A
| | - Hongzhe Li
- Research Service, VA Loma Linda Healthcare System, Loma Linda, California, U.S.A.,Department of Otolaryngology Head and Neck Surgery, Loma Linda University Health, Loma Linda, California, U.S.A
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Associations between Age-Related Hearing Loss and DietaryAssessment Using Data from Korean National Health andNutrition Examination Survey. Nutrients 2021; 13:nu13041230. [PMID: 33917838 PMCID: PMC8068238 DOI: 10.3390/nu13041230] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2021] [Revised: 04/06/2021] [Accepted: 04/06/2021] [Indexed: 02/07/2023] Open
Abstract
Age-related hearing loss (ARHL) is a major and rapidly growing public health problem that causes disability, social isolation, and socioeconomic cost. Nutritional status is known to cause many aging-related problems, and recent studies have suggested that there are interaction effects between ARHL and dietary factors. We aimed to investigate the association between ARHL and dietary assessment using data from the fifth Korean National Health and Nutrition Examination Survey, which is a nationwide cross-sectional survey that included 5201 participants aged ≥50 years from 2010 to 2012. All participants had normal findings on otoscopic examination and symmetric hearing thresholds of <15 dB between both sides. Nutritional survey data included food consumption and nutrient intake using the 24 h recall method. Data were analyzed using multiple regression models with complex sampling adjusted for confounding factors, such as age, sex, educational level, and history of diabetes. Higher intake of seeds and nuts, fruits, seaweed, and vitamin A were positively associated with better hearing. Our findings suggest that dietary antioxidants or anti-inflammatory food may help reduce ARHL.
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Köles L, Szepesy J, Berekméri E, Zelles T. Purinergic Signaling and Cochlear Injury-Targeting the Immune System? Int J Mol Sci 2019; 20:ijms20122979. [PMID: 31216722 PMCID: PMC6627352 DOI: 10.3390/ijms20122979] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2019] [Revised: 06/14/2019] [Accepted: 06/14/2019] [Indexed: 02/06/2023] Open
Abstract
Hearing impairment is the most common sensory deficit, affecting more than 400 million people worldwide. Sensorineural hearing losses currently lack any specific or efficient pharmacotherapy largely due to the insufficient knowledge of the pathomechanism. Purinergic signaling plays a substantial role in cochlear (patho)physiology. P2 (ionotropic P2X and the metabotropic P2Y) as well as adenosine receptors expressed on cochlear sensory and non-sensory cells are involved mostly in protective mechanisms of the cochlea. They are implicated in the sensitivity adjustment of the receptor cells by a K+ shunt and can attenuate the cochlear amplification by modifying cochlear micromechanics. Cochlear blood flow is also regulated by purines. Here, we propose to comprehend this field with the purine-immune interactions in the cochlea. The role of harmful immune mechanisms in sensorineural hearing losses has been emerging in the horizon of cochlear pathologies. In addition to decreasing hearing sensitivity and increasing cochlear blood supply, influencing the immune system can be the additional avenue for pharmacological targeting of purinergic signaling in the cochlea. Elucidating this complexity of purinergic effects on cochlear functions is necessary and it can result in development of new therapeutic approaches in hearing disabilities, especially in the noise-induced ones.
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Affiliation(s)
- László Köles
- Department of Pharmacology and Pharmacotherapy, Semmelweis University, H-1089 Budapest, Hungary.
| | - Judit Szepesy
- Department of Pharmacology and Pharmacotherapy, Semmelweis University, H-1089 Budapest, Hungary.
| | - Eszter Berekméri
- Department of Pharmacology and Pharmacotherapy, Semmelweis University, H-1089 Budapest, Hungary.
- Department of Ecology, University of Veterinary Medicine, H-1078 Budapest, Hungary.
| | - Tibor Zelles
- Department of Pharmacology and Pharmacotherapy, Semmelweis University, H-1089 Budapest, Hungary.
- Department of Pharmacology, Institute of Experimental Medicine, Hungarian Academy of Sciences, H-1083 Budapest, Hungary.
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10
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Hong H, Dooley KE, Starbird LE, Francis HW, Farley JE. Adverse outcome pathway for aminoglycoside ototoxicity in drug-resistant tuberculosis treatment. Arch Toxicol 2019; 93:1385-1399. [PMID: 30963202 DOI: 10.1007/s00204-019-02407-8] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2018] [Accepted: 02/06/2019] [Indexed: 12/22/2022]
Abstract
Individuals treated for multidrug-resistant tuberculosis (MDR-TB) with aminoglycosides (AGs) in resource-limited settings often experience permanent hearing loss. However, AG ototoxicity has never been conceptually integrated or causally linked to MDR-TB patients' pre-treatment health condition. We sought to develop a framework that examines the relationships between pre-treatment conditions and AG-induced hearing loss among MDR-TB-infected individuals in sub-Saharan Africa. The adverse outcome pathway (AOP) approach was used to develop a framework linking key events (KEs) within a biological pathway that results in adverse outcomes (AO), which are associated with chemical perturbation of a molecular initiating event (MIE). This AOP describes pathways initiating from AG accumulation in hair cells, sound transducers of the inner ear immediately after AG administration. After administration, the drug catalyzes cellular oxidative stress due to overproduction of reactive oxygen species. Since oxidative stress inhibits mitochondrial protein synthesis, hair cells undergo apoptotic cell death, resulting in irreversible hearing loss (AO). We identified the following pre-treatment conditions that worsen the causal linkage between MIE and AO: HIV, malnutrition, aging, noise, smoking, and alcohol use. The KEs are: (1) nephrotoxicity, pre-existing hearing loss, and hypoalbuminemia that catalyzes AG accumulation; (2) immunodeficiency and antioxidant deficiency that trigger oxidative stress pathways; and (3) co-administration of mitochondrial toxic drugs that hinder mitochondrial protein synthesis, causing apoptosis. This AOP clearly warrants the development of personalized interventions for patients undergoing MDR-TB treatment. Such interventions (i.e., choosing less ototoxic drugs, scheduling frequent monitoring, modifying nutritional status, avoiding poly-pharmacy) will be required to limit the burden of AG ototoxicity.
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Affiliation(s)
- Hyejeong Hong
- Johns Hopkins University School of Nursing, 525 North Wolfe Street, Baltimore, MD, 21205, USA. .,Johns Hopkins University School of Nursing, The REACH Initiative, 855 N. Wolfe Street, 21205, Baltimore, MD, USA.
| | - Kelly E Dooley
- Divisions of Clinical Pharmacology and Infectious Disease, Johns Hopkins University School of Medicine, 600 North Wolfe Street, 21205, Baltimore, MD, USA
| | - Laura E Starbird
- Center for Health Policy, Columbia University School of Nursing, 560 W 168 St, 10032, New York, NY, USA
| | - Howard W Francis
- Division of Head and Neck Surgery and Communication Sciences, Duke University School of Medicine, 40 Duke Medicine Circle, 27710, Durham, NC, USA
| | - Jason E Farley
- Johns Hopkins University School of Nursing, 525 North Wolfe Street, Baltimore, MD, 21205, USA.,Johns Hopkins University School of Nursing, The REACH Initiative, 855 N. Wolfe Street, 21205, Baltimore, MD, USA
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Hu BH, Zhang C, Frye MD. Immune cells and non-immune cells with immune function in mammalian cochleae. Hear Res 2018; 362:14-24. [PMID: 29310977 PMCID: PMC5911222 DOI: 10.1016/j.heares.2017.12.009] [Citation(s) in RCA: 58] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/15/2017] [Revised: 11/21/2017] [Accepted: 12/08/2017] [Indexed: 02/07/2023]
Abstract
The cochlea has an immune environment dominated by macrophages under resting conditions. When stressed, circulating monocytes enter the cochlea. These immune mediators, along with cochlear resident cells, organize a complex defense response against pathological challenges. Since the cochlea has minimal exposure to pathogens, most inflammatory conditions in the cochlea are sterile. Although the immune response is initiated for the protection of the cochlea, off-target effects can cause collateral damage to cochlear cells. A better understanding of cochlear immune capacity and regulation would therefore lead to development of new therapeutic treatments. Over the past decade, there have been many advances in our understanding of cochlear immune capacity. In this review, we provide an update and overview of the cellular components of cochlear immune capacity with a focus on macrophages in mammalian cochleae. We describe the composition and distribution of immune cells in the cochlea and suggest that phenotypic and functional characteristics of macrophages have site-specific diversity. We also highlight the response of immune cells to acute and chronic stresses and comment on the potential function of immune cells in cochlear homeostasis and disease development. Finally, we briefly review potential roles for cochlear resident cells in immune activities of the cochlea.
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Affiliation(s)
- Bo Hua Hu
- Center for Hearing and Deafness, University at Buffalo, 137 Cary Hall, 3435 Main Street, Buffalo, NY 14214, USA.
| | - Celia Zhang
- Center for Hearing and Deafness, University at Buffalo, 137 Cary Hall, 3435 Main Street, Buffalo, NY 14214, USA.
| | - Mitchell D Frye
- Center for Hearing and Deafness, University at Buffalo, 137 Cary Hall, 3435 Main Street, Buffalo, NY 14214, USA.
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Namikawa M, Sano A, Tateno T. Salicylate-Induced Suppression of Electrically Driven Activity in Brain Slices from the Auditory Cortex of Aging Mice. Front Aging Neurosci 2017; 9:395. [PMID: 29311894 PMCID: PMC5732918 DOI: 10.3389/fnagi.2017.00395] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2017] [Accepted: 11/14/2017] [Indexed: 11/15/2022] Open
Abstract
The prevalence of tinnitus is known to increase with age. The age-dependent mechanisms of tinnitus may have important implications for the development of new therapeutic treatments. High doses of salicylate can be used experimentally to induce transient tinnitus and hearing loss. Although accumulating evidence indicates that salicylate induces tinnitus by directly targeting neurons in the peripheral and central auditory systems, the precise effect of salicylate on neural networks in the auditory cortex (AC) is unknown. Here, we examined salicylate-induced changes in stimulus-driven laminar responses of AC slices with salicylate superfusion in young and aged senescence-accelerated-prone (SAMP) and -resistant (SAMR) mice. Of the two strains, SAMP1 is known to be a more suitable model of presbycusis. We recorded stimulus-driven laminar local field potential (LFP) responses at multi sites in AC slice preparations. We found that for all AC slices in the two strains, salicylate always reduced stimulus-driven LFP responses in all layers. However, for the amplitudes of the LFP responses, the two senescence-accelerated mice (SAM) strains showed different laminar properties between the pre- and post-salicylate conditions, reflecting strain-related differences in local circuits. As for the relationships between auditory brainstem response (ABR) thresholds and the LFP amplitude ratios in the pre- vs. post-salicylate condition, we found negative correlations in layers 2/3 and 4 for both older strains, and in layer 5 (L5) in older SAMR1. In contrast, the GABAergic agonist muscimol (MSC) led to positive correlations between ABR thresholds and LFP amplitude ratios in the pre- vs. post-MSC condition in younger SAM mice from both strains. Further, in younger mice, salicylate decreased the firing rate in AC L4 pyramidal neurons. Thus, salicylate can directly reduce neural excitability of L4 pyramidal neurons and thereby influence AC neural circuit activity. That we observed age-dependent effects of salicylate and varied GABAergic sensitivity in the AC among mouse strains with hearing loss implies that potential therapeutic mechanisms for tinnitus may operate differently in young vs. aged subjects. Therefore, scientists developing new therapeutic modalities for tinnitus treatment should consider using both aged and young animals.
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Affiliation(s)
- Minoru Namikawa
- Department of Bioengineering and Bioinformatics, Graduate School of Information Science and Technology, Hokkaido University, Sapporo, Japan
| | - Ayaka Sano
- Department of Bioengineering and Bioinformatics, Graduate School of Information Science and Technology, Hokkaido University, Sapporo, Japan
| | - Takashi Tateno
- Department of Bioengineering and Bioinformatics, Graduate School of Information Science and Technology, Hokkaido University, Sapporo, Japan
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Kalinec GM, Lomberk G, Urrutia RA, Kalinec F. Resolution of Cochlear Inflammation: Novel Target for Preventing or Ameliorating Drug-, Noise- and Age-related Hearing Loss. Front Cell Neurosci 2017; 11:192. [PMID: 28736517 PMCID: PMC5500902 DOI: 10.3389/fncel.2017.00192] [Citation(s) in RCA: 75] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2017] [Accepted: 06/20/2017] [Indexed: 12/11/2022] Open
Abstract
A significant number of studies support the idea that inflammatory responses are intimately associated with drug-, noise- and age-related hearing loss (DRHL, NRHL and ARHL). Consequently, several clinical strategies aimed at reducing auditory dysfunction by preventing inflammation are currently under intense scrutiny. Inflammation, however, is a normal adaptive response aimed at restoring tissue functionality and homeostasis after infection, tissue injury and even stress under sterile conditions, and suppressing it could have unintended negative consequences. Therefore, an appropriate approach to prevent or ameliorate DRHL, NRHL and ARHL should involve improving the resolution of the inflammatory process in the cochlea rather than inhibiting this phenomenon. The resolution of inflammation is not a passive response but rather an active, highly controlled and coordinated process. Inflammation by itself produces specialized pro-resolving mediators with critical functions, including essential fatty acid derivatives (lipoxins, resolvins, protectins and maresins), proteins and peptides such as annexin A1 and galectins, purines (adenosine), gaseous mediators (NO, H2S and CO), as well as neuromodulators like acetylcholine and netrin-1. In this review article, we describe recent advances in the understanding of the resolution phase of inflammation and highlight therapeutic strategies that might be useful in preventing inflammation-induced cochlear damage. In particular, we emphasize beneficial approaches that have been tested in pre-clinical models of inflammatory responses induced by recognized ototoxic drugs such as cisplatin and aminoglycoside antibiotics. Since these studies suggest that improving the resolution process could be useful for the prevention of inflammation-associated diseases in humans, we discuss the potential application of similar strategies to prevent or mitigate DRHL, NRHL and ARHL.
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Affiliation(s)
- Gilda M Kalinec
- Laboratory of Auditory Cell Biology, Department of Head and Neck Surgery, David Geffen School of Medicine, University of CaliforniaLos Angeles, Los Angeles, CA, United States
| | - Gwen Lomberk
- Epigenetics and Chromatin Dynamics Laboratory, Translational Epigenomic Program, Center for Individualized Medicine (CIM) Mayo ClinicRochester, MN, United States
| | - Raul A Urrutia
- Epigenetics and Chromatin Dynamics Laboratory, Translational Epigenomic Program, Center for Individualized Medicine (CIM) Mayo ClinicRochester, MN, United States
| | - Federico Kalinec
- Laboratory of Auditory Cell Biology, Department of Head and Neck Surgery, David Geffen School of Medicine, University of CaliforniaLos Angeles, Los Angeles, CA, United States
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Yamamura D, Sano A, Tateno T. An analysis of current source density profiles activated by local stimulation in the mouse auditory cortex in vitro. Brain Res 2017; 1659:96-112. [PMID: 28119054 DOI: 10.1016/j.brainres.2017.01.021] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2016] [Revised: 01/14/2017] [Accepted: 01/16/2017] [Indexed: 01/27/2023]
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Iwai H, Inaba M. Fetal thymus graft enables recovery from age-related hearing loss and expansion of CD4-Positive T cells expressing IL-1 receptor type 2 and regulatory T Cells. IMMUNITY & AGEING 2015; 12:26. [PMID: 26673738 PMCID: PMC4678479 DOI: 10.1186/s12979-015-0053-9] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/06/2015] [Accepted: 12/07/2015] [Indexed: 12/25/2022]
Abstract
Background Accumulating evidence has indicated the relationship between the systemic immune system and the central nervous system including the inner ear. Results We have shown that age-related developments of T-cell dysfunction, hearing loss, and degeneration of cochlear spiral ganglion (SG) neurons observed in 6-month-old mice were recovered in 12 months old mice which previously given fetal thymus transplants twice. We have also demonstrated that CD4+ T cells expressing interleukin 1 receptor type 2 (IL-1R2) and naturally occurring regulatory T cells (nTregs), which expanded in aged 12-month-old mice, were reduced in the thymus-grafted mice of the same age. Conclusion It is conceivable that the rejuvenation of systemic immune function by fetal thymus grafts contributes not only to the activation of cellular immunity but also to the decrease of IL-1R2+ CD4+ T cells or nTregs, which cells accelerate both age-related hearing loss (AHL) and neurodegeneration of the cochlear neurons. Further studies on the interactions among IL-1R2 expression on CD4+ T cells, Tregs, and neuronal cells and also on the relationships between fetal thymus grafting and the rejuvenation of systemic immunity should be designed in order to advance towards therapeutic effects on neurosenescence, including AHL.
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Affiliation(s)
- Hiroshi Iwai
- Department of Otolaryngology, Takii Hospital, Kansai Medical University, Moriguchi, Osaka Japan
| | - Muneo Inaba
- First Department of Medicine, Hirakata Hospital, Kansai Medical University, Hirakata, Osaka Japan
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Cai Q, Vethanayagam RR, Yang S, Bard J, Jamison J, Cartwright D, Dong Y, Hu BH. Molecular profile of cochlear immunity in the resident cells of the organ of Corti. J Neuroinflammation 2014; 11:173. [PMID: 25311735 PMCID: PMC4198756 DOI: 10.1186/s12974-014-0173-8] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2014] [Accepted: 09/25/2014] [Indexed: 12/20/2022] Open
Abstract
BACKGROUND The cochlea is the sensory organ of hearing. In the cochlea, the organ of Corti houses sensory cells that are susceptible to pathological insults. While the organ of Corti lacks immune cells, it does have the capacity for immune activity. We hypothesized that resident cells in the organ of Corti were responsible for the stress-induced immune response of the organ of Corti. This study profiled the molecular composition of the immune system in the organ of Corti and examined the immune response of non-immune epithelial cells to acoustic overstimulation. METHODS Using high-throughput RNA-sequencing and qRT-PCR arrays, we identified immune- and inflammation-related genes in both the cochlear sensory epithelium and the organ of Corti. Using bioinformatics analyses, we cataloged the immune genes expressed. We then examined the response of these genes to acoustic overstimulation and determined how changes in immune gene expression were related to sensory cell damage. RESULTS The RNA-sequencing analysis reveals robust expression of immune-related genes in the cochlear sensory epithelium. The qRT-PCR array analysis confirms that many of these genes are constitutively expressed in the resident cells of the organ of Corti. Bioinformatics analyses reveal that the genes expressed are linked to the Toll-like receptor signaling pathway. We demonstrate that expression of Toll-like receptor signaling genes is predominantly from the supporting cells in the organ of Corti cells. Importantly, our data demonstrate that these Toll-like receptor pathway genes are able to respond to acoustic trauma and that their expression changes are associated with sensory cell damage. CONCLUSION The cochlear resident cells in the organ of Corti have immune capacity and participate in the cochlear immune response to acoustic overstimulation.
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Affiliation(s)
| | | | | | | | | | | | | | - Bo Hua Hu
- Center for Hearing and Deafness, State University of New York at Buffalo, 137 Cary Hall, 3435 Main Street, Buffalo 14214, NY, USA.
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Dong Y, Li M, Liu P, Song H, Zhao Y, Shi J. Genes involved in immunity and apoptosis are associated with human presbycusis based on microarray analysis. Acta Otolaryngol 2014; 134:601-8. [PMID: 24552194 DOI: 10.3109/00016489.2014.880795] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
CONCLUSIONS Genes involved in immunity and apoptosis were associated with human presbycusis. CCR3 and GILZ played an important role in the pathogenesis of presbycusis, probably through regulating chemokine receptor, T-cell apoptosis, or T-cell activation pathways. OBJECTIVES To identify genes associated with human presbycusis and explore the molecular mechanism of presbycusis. METHODS Hearing function was tested by pure-tone audiometry. Microarray analysis was performed to identify presbycusis-correlated genes by Illumina Human-6 BeadChip using the peripheral blood samples of subjects. To identify biological process categories and pathways associated with presbycusis-correlated genes, bioinformatics analysis was carried out by Gene Ontology Tree Machine (GOTM) and database for annotation, visualization, and integrated discovery (DAVID). Quantitative RT-PCR (qRT-PCR) was used to validate the microarray data. RESULTS Microarray analysis identified 469 up-regulated genes and 323 down-regulated genes. Both the dominant biological processes by Gene Ontology (GO) analysis and the enriched pathways by Kyoto encyclopedia of genes and genomes (KEGG) and BIOCARTA showed that genes involved in immunity and apoptosis were associated with presbycusis. In addition, CCR3, GILZ, CXCL10, and CX3CR1 genes showed consistent difference between groups for both the gene chip and qRT-PCR data. The differences of CCR3 and GILZ between presbycusis patients and controls were statistically significant (p < 0.05).
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Affiliation(s)
- Yang Dong
- Experimental Teaching Center, Shanghai University of Traditional Chinese Medicine
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Verschuur C, Agyemang-Prempeh A, Newman TA. Inflammation is associated with a worsening of presbycusis: Evidence from the MRC national study of hearing. Int J Audiol 2014; 53:469-75. [DOI: 10.3109/14992027.2014.891057] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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Fetal thymus graft prevents age-related hearing loss and up regulation of the IL-1 receptor type II gene in CD4+ T cells. J Neuroimmunol 2012; 250:1-8. [DOI: 10.1016/j.jneuroim.2012.05.007] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2012] [Revised: 04/08/2012] [Accepted: 05/04/2012] [Indexed: 12/11/2022]
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Pandit SR, Sullivan JM, Egger V, Borecki AA, Oleskevich S. Functional Effects of Adult Human Olfactory Stem Cells on Early-Onset Sensorineural Hearing Loss. Stem Cells 2011; 29:670-7. [DOI: 10.1002/stem.609] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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Fetoni AR, Picciotti PM, Paludetti G, Troiani D. Pathogenesis of presbycusis in animal models: a review. Exp Gerontol 2011; 46:413-25. [PMID: 21211561 DOI: 10.1016/j.exger.2010.12.003] [Citation(s) in RCA: 131] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2010] [Revised: 11/04/2010] [Accepted: 12/15/2010] [Indexed: 12/14/2022]
Abstract
Presbycusis is the most common cause of hearing loss in aged subjects, reducing individual's communicative skills. Age related hearing loss can be defined as a progressive, bilateral, symmetrical hearing loss due to age related degeneration and it can be considered a multifactorial complex disorder, with both environmental and genetic factors contributing to the aetiology of the disease. The decline in hearing sensitivity caused by ageing is related to the damage at different levels of the auditory system (central and peripheral). Histologically, the aged cochlea shows degeneration of the stria vascularis, the sensorineural epithelium, and neurons of the central auditory pathways. The mechanisms responsible for age-associated hearing loss are still incompletely characterized. This work aims to give a broad overview of the scientific findings related to presbycusis, focusing mainly on experimental studies in animal models.
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Affiliation(s)
- Anna R Fetoni
- Institute of Otolaryngology, School of Medicine, Catholic University of Rome, Largo A. Gemelli, 8 00168 Rome, Italy.
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