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Lu M, Xian F, Jin X, Hong G, Fu X, Wang S, Li X, Yang H, Li H, Zhang H, Yang Y, Xiao J, Dong H, Liu Y, Shen H, Lv P. Upregulation of the Ca v1.3 channel in inner hair cells by interleukin 6-dependent inflammaging contributes to age-related hearing loss. Aging Cell 2024:e14305. [PMID: 39148148 DOI: 10.1111/acel.14305] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2024] [Revised: 07/02/2024] [Accepted: 07/24/2024] [Indexed: 08/17/2024] Open
Abstract
Age-related hearing loss (AHL) is the most common sensory disorder amongst the older population. Inflammaging is a ≈chronic low-grade inflammation that worsens with age and is an early sign of AHL; however, the underlying mechanisms remain unclear. We used electrophysiological and genetic approaches to establish the importance of interleukin 6 (IL-6)-dependent inflammation in AHL. Elevated IL-6 in the cochlea enhanced Cav1.3 calcium channel function in the inner hair cell (IHC) synapse in mice with AHL. IL-6 upregulated the Cav1.3 channel via the Janus kinase-mitogen activated kinase pathway, causing neurotransmitter excitotoxicity and synapse impairment; IL-6 deficiency or the administration of a Cav1.3 channel blocker attenuated this age-related damage, and rescued hearing loss. Thus, IL-6-dependent inflammaging upregulated the Cav1.3 channel in IHCs, contributing to AHL. Our findings could help the comprehensive understanding of inflammaging's effects on AHL, aiding in early intervention to protect against hearing decline.
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Affiliation(s)
- Mingshun Lu
- Department of Pharmacology, The Key Laboratory of Neural and Vascular Biology, Ministry of Education, The Key Laboratory of New Drug Pharmacology and Toxicology, The Hebei Collaboration Innovation Center for Mechanism, Diagnosis and Treatment of Neurological and Psychiatric Disease, Hebei Medical University, Shijiazhuang, Hebei, China
| | - Fuyu Xian
- Department of Pharmacology, The Key Laboratory of Neural and Vascular Biology, Ministry of Education, The Key Laboratory of New Drug Pharmacology and Toxicology, The Hebei Collaboration Innovation Center for Mechanism, Diagnosis and Treatment of Neurological and Psychiatric Disease, Hebei Medical University, Shijiazhuang, Hebei, China
| | - Xishuo Jin
- Department of Pharmacology, The Key Laboratory of Neural and Vascular Biology, Ministry of Education, The Key Laboratory of New Drug Pharmacology and Toxicology, The Hebei Collaboration Innovation Center for Mechanism, Diagnosis and Treatment of Neurological and Psychiatric Disease, Hebei Medical University, Shijiazhuang, Hebei, China
| | - Guodong Hong
- Medical Science and Technology Innovation Center, Shandong First Medical University & Shandong Academy of Medical Sciences, Jinan, Shandong, China
| | - Xiaolong Fu
- Shandong Provincial Hospital, Medical Science and Technology Innovation Center, College of Clinical and Basic Medicine, Shandong First Medical University & Shandong Academy of Medical Sciences, Jinan, Shandong, China
- Department of Neurology, Aerospace Center Hospital, School of Life Science, Beijing Institute of Technology, Beijing, China
| | - Shengnan Wang
- Department of Pharmacology, The Key Laboratory of Neural and Vascular Biology, Ministry of Education, The Key Laboratory of New Drug Pharmacology and Toxicology, The Hebei Collaboration Innovation Center for Mechanism, Diagnosis and Treatment of Neurological and Psychiatric Disease, Hebei Medical University, Shijiazhuang, Hebei, China
| | - Xinyu Li
- Department of Pharmacology, The Key Laboratory of Neural and Vascular Biology, Ministry of Education, The Key Laboratory of New Drug Pharmacology and Toxicology, The Hebei Collaboration Innovation Center for Mechanism, Diagnosis and Treatment of Neurological and Psychiatric Disease, Hebei Medical University, Shijiazhuang, Hebei, China
| | - Haichao Yang
- Department of Pharmacology, The Key Laboratory of Neural and Vascular Biology, Ministry of Education, The Key Laboratory of New Drug Pharmacology and Toxicology, The Hebei Collaboration Innovation Center for Mechanism, Diagnosis and Treatment of Neurological and Psychiatric Disease, Hebei Medical University, Shijiazhuang, Hebei, China
| | - Hongchen Li
- Department of Pharmacology, The Key Laboratory of Neural and Vascular Biology, Ministry of Education, The Key Laboratory of New Drug Pharmacology and Toxicology, The Hebei Collaboration Innovation Center for Mechanism, Diagnosis and Treatment of Neurological and Psychiatric Disease, Hebei Medical University, Shijiazhuang, Hebei, China
| | - Haiwei Zhang
- Department of Pharmacology, The Key Laboratory of Neural and Vascular Biology, Ministry of Education, The Key Laboratory of New Drug Pharmacology and Toxicology, The Hebei Collaboration Innovation Center for Mechanism, Diagnosis and Treatment of Neurological and Psychiatric Disease, Hebei Medical University, Shijiazhuang, Hebei, China
| | - Yuxin Yang
- Department of Pharmacology, The Key Laboratory of Neural and Vascular Biology, Ministry of Education, The Key Laboratory of New Drug Pharmacology and Toxicology, The Hebei Collaboration Innovation Center for Mechanism, Diagnosis and Treatment of Neurological and Psychiatric Disease, Hebei Medical University, Shijiazhuang, Hebei, China
| | - Jundan Xiao
- Department of Pharmacology, The Key Laboratory of Neural and Vascular Biology, Ministry of Education, The Key Laboratory of New Drug Pharmacology and Toxicology, The Hebei Collaboration Innovation Center for Mechanism, Diagnosis and Treatment of Neurological and Psychiatric Disease, Hebei Medical University, Shijiazhuang, Hebei, China
| | - Hui Dong
- Department of Neurology, The Second Hospital of Hebei Medical University, The Key Laboratory of Neurology, Ministry of Education, Hebei Medical University, Neurological Laboratory of Hebei Province, Shijiazhuang, Hebei, China
| | - Yaling Liu
- Department of Neurology, The Second Hospital of Hebei Medical University, The Key Laboratory of Neurology, Ministry of Education, Hebei Medical University, Neurological Laboratory of Hebei Province, Shijiazhuang, Hebei, China
| | - Haitao Shen
- Lab of Pathology, Hebei Medical University,, Shijiazhuang, Hebei, China
- Hebei Collaborative Innovation Center of Tumor Microecological Metabolism Regulation, Affiliated Hospital of Hebei University, Baoding, Hebei, China
| | - Ping Lv
- Department of Pharmacology, The Key Laboratory of Neural and Vascular Biology, Ministry of Education, The Key Laboratory of New Drug Pharmacology and Toxicology, The Hebei Collaboration Innovation Center for Mechanism, Diagnosis and Treatment of Neurological and Psychiatric Disease, Hebei Medical University, Shijiazhuang, Hebei, China
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Liu J, Si Y, Huang X, Lin X, Lu L, Wu C, Guan X, Liang Y. Vitamin C inhibits NLRP3 inflammasome activation and delays the development of age-related hearing loss in male C57BL/6 mice. Neurosci Lett 2024; 836:137897. [PMID: 39004114 DOI: 10.1016/j.neulet.2024.137897] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2023] [Revised: 05/08/2024] [Accepted: 07/10/2024] [Indexed: 07/16/2024]
Abstract
The efficacy of vitamin C in age-related hearing loss, i.e., presbycusis, remains debatable. On a separate note, inflammation induced by the NOD-like receptor family pyrin domain containing 3 (NLRP3) inflammasome is involved in the progression of presbycusis. In this study, we investigated the effect of vitamin C on male C57BL/6 mice's presbycusis and NLRP3 inflammasome. The results showed that vitamin C treatment improved hearing, reduced the production of inflammatory factors, inhibited NLRP3 inflammasome activation, and decreased cytosolic mitochondrial DNA (mtDNA) in the C57BL/6 mouse cochlea, inferior colliculus, and auditory cortex. According to this study, vitamin C protects auditory function in male C57BL/6 presbycusis mice through reducing mtDNA release, inhibiting the NLRP3 inflammasome activation in the auditory pathway. Our study provides a theoretical basis for applying vitamin C to treat presbycusis.
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Affiliation(s)
- Jinlan Liu
- Department of Otolaryngology-Head & Neck Surgery, Guangxi International Zhuang Medicine Hospital Affiliated to Guangxi University of Chinese Medicine, Nanning, Guangxi, China
| | - Yongfeng Si
- Department of Otolaryngology-Head & Neck Surgery, Guangxi International Zhuang Medicine Hospital Affiliated to Guangxi University of Chinese Medicine, Nanning, Guangxi, China
| | - Xiaoying Huang
- Department of Otolaryngology-Head & Neck Surgery, Guangxi International Zhuang Medicine Hospital Affiliated to Guangxi University of Chinese Medicine, Nanning, Guangxi, China
| | - Xinran Lin
- Department of Otolaryngology-Head & Neck Surgery, Guangxi International Zhuang Medicine Hospital Affiliated to Guangxi University of Chinese Medicine, Nanning, Guangxi, China
| | - Lingjuan Lu
- Department of Otolaryngology-Head & Neck Surgery, Guangxi International Zhuang Medicine Hospital Affiliated to Guangxi University of Chinese Medicine, Nanning, Guangxi, China
| | - Changlin Wu
- Department of Otolaryngology-Head & Neck Surgery, Guangxi International Zhuang Medicine Hospital Affiliated to Guangxi University of Chinese Medicine, Nanning, Guangxi, China
| | - Xuan Guan
- Department of Otolaryngology-Head & Neck Surgery, Guangxi International Zhuang Medicine Hospital Affiliated to Guangxi University of Chinese Medicine, Nanning, Guangxi, China
| | - Yunsheng Liang
- Department of Breast Disease, Guangxi International Zhuang Medicine Hospital Affiliated to Guangxi University of Chinese Medicine, Nanning, Guangxi, China.
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Su Z, Liu Y, Zhang W, Liang W, Chen Y, Cao J, Liu Y, Zheng Y, Li Q. Endoplasmic reticulum stress-induced necroptosis promotes cochlear inflammation: Implications for age-related hearing loss. Exp Gerontol 2024; 189:112401. [PMID: 38490286 DOI: 10.1016/j.exger.2024.112401] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2023] [Revised: 02/11/2024] [Accepted: 03/11/2024] [Indexed: 03/17/2024]
Abstract
Age-related hearing loss (ARHL) is the most common sensory disorder associated with human aging. Chronic inflammation is supposed to be an important contributor to ARHL. Yet, the underlying mechanisms of developing cochlear inflammation are still not well understood. In this study, we found that the inflammation, endoplasmic reticulum (ER) stress and necroptosis signalings are activated in the cochlea of aged C57BL/6 mice. ER stress activator tunicamycin (TM) induced necroptosis in cochlear HEI-OC1 cells and cochlear explants, while necroptosis inhibitors protected cochlear cells from ER stress-induced cell death. The antioxidants inhibited necroptosis and protected HEI-OC1 cells from TM insults. Necroptotic HEI-OC1 cells promoted the activation of the co-cultured macrophages via Myd88 signaling. Moreover, necroptosis inhibitor protected from TM-induced hearing loss, and inhibited inflammation in C57BL/6 mice. These findings suggest that ER stress-induced necroptosis promotes cochlear inflammation and hearing loss. Targeting necroptosis serves as a potential approach for the treatment of cochlear inflammation and ARHL.
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Affiliation(s)
- Zhongwu Su
- Department of Otolaryngology, Nanfang Hospital, Southern Medical University, Guangzhou, China
| | - Yi Liu
- Department of Otolaryngology, Guangdong Women and Children Hospital, Guangzhou, China
| | - Weijian Zhang
- Department of Otolaryngology, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, China
| | - Wenhui Liang
- Department of Otolaryngology, Nanfang Hospital, Southern Medical University, Guangzhou, China
| | - Yuyan Chen
- Department of Otolaryngology, Nanfang Hospital, Southern Medical University, Guangzhou, China
| | - Jinyuan Cao
- Department of Otolaryngology, Nanfang Hospital, Southern Medical University, Guangzhou, China
| | - Yu Liu
- Department of Otolaryngology, Nanfang Hospital, Southern Medical University, Guangzhou, China
| | - Yiqing Zheng
- Department of Otolaryngology, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, China.
| | - Qi Li
- Department of Otolaryngology, Nanfang Hospital, Southern Medical University, Guangzhou, China.
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Qiu K, Mao M, Pang W, Deng D, Ren J, Zhao Y. The emerging roles and therapeutic implications of immunosenescence-mediated inflammaging in age-related hearing loss. AMERICAN JOURNAL OF STEM CELLS 2024; 13:101-109. [PMID: 38765806 PMCID: PMC11101989 DOI: 10.62347/dtap3592] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/08/2023] [Accepted: 04/25/2024] [Indexed: 05/22/2024]
Abstract
Age-related hearing loss (ARHL) represents one of the most prevalent chronic sensory deficits experienced by the elderly, significantly diminishing their quality of life and correlating with various medical and psychological morbidities. This condition arises from the cumulative effects of aging on the auditory system, implicating intricate interactions between genetic predispositions and environmental factors. Aging entails a progressive decline in immune system functionality, termed immunosenescence, leading to a chronic low-grade inflammation known as inflammaging. This phenomenon potentially serves as a common mechanism underlying ARHL and other age-related pathologies. Recent research suggests that rejuvenating immunosenescence could mitigate inflammaging and ameliorate age-related functional declines, offering promising insights into anti-aging therapies. Consequently, this review endeavors to elucidate the role of immunosenescence-mediated inflammaging in ARHL progression and discuss its therapeutic implications.
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Affiliation(s)
- Ke Qiu
- Department of Otolaryngology-Head and Neck Surgery, West China Hospital, Sichuan University Chengdu, Sichuan, China
| | - Minzi Mao
- Department of Otolaryngology-Head and Neck Surgery, West China Hospital, Sichuan University Chengdu, Sichuan, China
| | - Wendu Pang
- Department of Otolaryngology-Head and Neck Surgery, West China Hospital, Sichuan University Chengdu, Sichuan, China
| | - Di Deng
- Department of Otolaryngology-Head and Neck Surgery, West China Hospital, Sichuan University Chengdu, Sichuan, China
| | - Jianjun Ren
- Department of Otolaryngology-Head and Neck Surgery, West China Hospital, Sichuan University Chengdu, Sichuan, China
| | - Yu Zhao
- Department of Otolaryngology-Head and Neck Surgery, West China Hospital, Sichuan University Chengdu, Sichuan, China
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Rincon Sabatino S, Sangaletti R, Griswold A, Dietrich WD, King CS, Rajguru SM. Transcriptional response to mild therapeutic hypothermia in noise-induced cochlear injury. Front Neurosci 2024; 17:1296475. [PMID: 38298897 PMCID: PMC10827921 DOI: 10.3389/fnins.2023.1296475] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2023] [Accepted: 12/18/2023] [Indexed: 02/02/2024] Open
Abstract
Introduction Prevention or treatment for acoustic injury has been met with many translational challenges, resulting in the absence of FDA-approved interventions. Localized hypothermia following noise exposure mitigates acute cochlear injury and may serve as a potential avenue for therapeutic approaches. However, the mechanisms by which hypothermia results in therapeutic improvements are poorly understood. Methods This study performs the transcriptomic analysis of cochleae from juvenile rats that experienced noise-induced hearing loss (NIHL) followed by hypothermia or control normothermia treatment. Results Differential gene expression results from RNA sequencing at 24 h post-exposure to noise suggest that NIHL alone results in increased inflammatory and immune defense responses, involving complement activation and cytokine-mediated signaling. Hypothermia treatment post-noise, in turn, may mitigate the acute inflammatory response. Discussion This study provides a framework for future research to optimize hypothermic intervention for ameliorating hearing loss and suggests additional pathways that could be targeted for NIHL therapeutic intervention.
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Affiliation(s)
| | - Rachele Sangaletti
- Department of Otolaryngology, University of Miami, Coral Gables, FL, United States
| | - Anthony Griswold
- Department of Human Genetics, University of Miami, Coral Gables, FL, United States
| | - W. Dalton Dietrich
- The Miami Project to Cure Paralysis, University of Miami, Coral Gables, FL, United States
| | | | - Suhrud M. Rajguru
- Department of Biomedical Engineering, University of Miami, Coral Gables, FL, United States
- Department of Otolaryngology, University of Miami, Coral Gables, FL, United States
- The Miami Project to Cure Paralysis, University of Miami, Coral Gables, FL, United States
- RestorEar Devices LLC, Bozeman, MT, United States
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Kuang X, Zhao W, Wang Q, Sun Z, Xu F, Geng R, Li B, Zheng T, Zheng Q. RNA-seq analysis highlights DNA replication and DNA repair associated with early-onset hearing loss in the cochlea of DBA/2J mice. Life Sci 2024; 337:122350. [PMID: 38103727 DOI: 10.1016/j.lfs.2023.122350] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2023] [Revised: 12/05/2023] [Accepted: 12/09/2023] [Indexed: 12/19/2023]
Abstract
AIMS Age-related hearing loss (ARHL) is a significant health concern, and DBA/2J (D2) and C57BL/6 (B6) mouse strains serve as valuable models for its study. B6 mice, harboring a homozygous ahl allele in Cdh23, manifest high-frequency hearing loss at 3 months. In contrast, D2 mice, carrying the R109H variant of the Fascin-2 gene (Fscn2), experience early-onset hearing loss by 3 weeks. Yet, the underlying molecular mechanisms driving early-onset hearing loss in D2 mice remain elusive. This study aimed to identify novel genes and regulatory pathways as therapeutic targets for early deafness. MAIN METHODS This study employs RNA-sequencing (RNA-seq) to analyze cochlear mRNA expression at two different ages in D2 and B6 mice, respectively. The differentially expressed genes (DEGs) are uniquely associated with D2 mice by Venn diagram analysis. A protein-protein interaction (PPI) network is further constructed, followed by module analysis utilizing MCODE. Enrichment analysis of GO and KEGG pathways revealed biological functions and molecular pathways. The PPI network and VarElect analysis are conducted for genes within these pathways, facilitating the identification of pivotal genes based on scoring criteria. Subsequently, five genes are meticulously selected and validated through qRT-PCR. KEY FINDINGS Notably, 1181 DEGs are uniquely associated with D2 mice by Venn diagram analysis. GO and KEGG pathway enrichment analyses shed light on distinctive pathways in D2 mice, encompassing DNA replication, mismatch repair, base excision repair, and nucleotide excision repair, which are associated with apoptosis. Five genes involved in these pathways were finally selected and validated by qRT-PCR. Their down-regulation with age is consistent with RNA-seq result. SIGNIFICANCE Our study underscores the potential implication of down-regulated genes associated with DNA replication and DNA damage repair in the early-onset hearing loss observed in D2 mice.
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Affiliation(s)
- Xiaojing Kuang
- School of Basic Medicine, Qingdao University, 266000 Qingdao, Shandong, China
| | - Wenben Zhao
- Hearing and Speech Rehabilitation Institute, College of Special Education and Rehabilitation, Binzhou Medical University, 264000 Yantai, Shandong, China
| | - Qin Wang
- Hearing and Speech Rehabilitation Institute, College of Special Education and Rehabilitation, Binzhou Medical University, 264000 Yantai, Shandong, China
| | - Zehua Sun
- Department of Radiology, Qindao University Medical College Affiliated Yantai Yuhuangding Hospital, 264000 Yantai, Shandong, China
| | - Fuyi Xu
- Precision Medicine Research Center, School of Pharmacy, Binzhou Medical University, 264000 Yantai, Shandong, China
| | - Ruishuang Geng
- Hearing and Speech Rehabilitation Institute, College of Special Education and Rehabilitation, Binzhou Medical University, 264000 Yantai, Shandong, China
| | - Bo Li
- Hearing and Speech Rehabilitation Institute, College of Special Education and Rehabilitation, Binzhou Medical University, 264000 Yantai, Shandong, China
| | - Tihua Zheng
- Hearing and Speech Rehabilitation Institute, College of Special Education and Rehabilitation, Binzhou Medical University, 264000 Yantai, Shandong, China
| | - Qingyin Zheng
- School of Basic Medicine, Qingdao University, 266000 Qingdao, Shandong, China; Hearing and Speech Rehabilitation Institute, College of Special Education and Rehabilitation, Binzhou Medical University, 264000 Yantai, Shandong, China.
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Rahman MT, Bailey EM, Gansemer BM, Pieper AA, Manak JR, Green SH. Anti-inflammatory Therapy Protects Spiral Ganglion Neurons After Aminoglycoside Antibiotic-Induced Hair Cell Loss. Neurotherapeutics 2023; 20:578-601. [PMID: 36697994 PMCID: PMC10121993 DOI: 10.1007/s13311-022-01336-2] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/06/2022] [Indexed: 01/26/2023] Open
Abstract
Destruction of cochlear hair cells by aminoglycoside antibiotics leads to gradual death of the spiral ganglion neurons (SGNs) that relay auditory information to the brain, potentially limiting the efficacy of cochlear implants. Because the reasons for this cochlear neurodegeneration are unknown, there are no neuroprotective strategies for patients. To investigate this problem, we assessed transcriptomic changes in the rat spiral ganglion following aminoglycoside antibiotic (kanamycin)-induced hair cell destruction. We observed selectively increased expression of immune and inflammatory response genes and increased abundance of activated macrophages in spiral ganglia by postnatal day 32 in kanamycin-deafened rats, preceding significant SGN degeneration. Treatment with the anti-inflammatory medications dexamethasone and ibuprofen diminished long-term SGN degeneration. Ibuprofen and dexamethasone also diminished macrophage activation. Efficacy of ibuprofen treatment was augmented by co-administration of the nicotinamide adenine dinucleotide-stabilizing agent P7C3-A20. Our results support a critical role of neuroinflammation in SGN degeneration after aminoglycoside antibiotic-mediated cochlear hair cell loss, as well as a neuroprotective strategy that could improve cochlear implant efficacy.
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Affiliation(s)
- Muhammad T Rahman
- Department of Biology, University of Iowa, Iowa City, IA, 52242, USA
| | - Erin M Bailey
- Department of Biology, University of Iowa, Iowa City, IA, 52242, USA
| | | | - Andrew A Pieper
- Harrington Discovery Institute, University Hospitals Cleveland Medical Center, Cleveland, OH, 44106, USA
- Department of Psychiatry, Case Western Reserve University, Cleveland, OH, 44106, USA
- Geriatric Psychiatry, GRECC, Louis Stokes Cleveland VA Medical Center, Cleveland, OH, 44106, USA
- Institute for Transformative Molecular Medicine, School of Medicine, Case Western Reserve University, Cleveland, OH, 44106, USA
| | - J Robert Manak
- Department of Biology, University of Iowa, Iowa City, IA, 52242, USA
- Department of Pediatrics, University of Iowa, Iowa City, IA, 52242, USA
| | - Steven H Green
- Department of Biology, University of Iowa, Iowa City, IA, 52242, USA.
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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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Li L, Xu K, Bai X, Wang Z, Tian X, Chen X. UCHL1 regulated by Sp1 ameliorates cochlear hair cell senescence and oxidative damage. Exp Ther Med 2023; 25:94. [PMID: 36761006 PMCID: PMC9905655 DOI: 10.3892/etm.2023.11793] [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: 07/08/2022] [Accepted: 12/09/2022] [Indexed: 01/11/2023] Open
Abstract
Age-related hearing loss (ARHL) is the most common cause of hearing loss in the elderly. Ubiquitin carboxyl-terminal hydrolase L1 (UCHL1) is a deubiquitinating enzyme involved in several types of human disease. The present study aimed to investigate the effect of UCHL1 on a hydrogen peroxide (H2O2)-induced ARHL model in cochlear hair cells and uncover its underlying mechanism. Reverse transcription-quantitative (RT-q)PCR and western blot analysis were used to assess UCHL1 expression in HEI-OC1 cells exposed to H2O2. Following UCHL1 overexpression in H2O2-induced HEI-OC1 cells, cell activity was assessed by Cell Counting Kit-8 assay. The content of oxidative stress-associated markers including superoxide dismutase (SOD), glutathione peroxidase (GSH-Px) and reactive oxygen species (ROS ) was measured using corresponding commercial kits. Cell apoptosis was evaluated by TUNEL assay and western blot analysis. Cell senescence was assessed by senescence-associated β-galactosidase staining and western blot analysis. RT-qPCR and western blot analysis were applied to measure mRNA and protein expression levels, respectively, of specificity protein 1 (Sp1) in H2O2-treated HEI-OC1 cells. In addition, the association between UCHL1 and Sp1 was verified by luciferase reporter and chromatin immunoprecipitation (ChIP) assay. The mRNA and protein expression levels of UCHL1 were also determined in Sp1-overexpressing cells by RT-qPCR and western blot analysis, respectively. Following Sp1 overexpression in UCHL1-overexpressing H2O2-treated HEI-OC1 cells, cell activity, oxidative stress, apoptosis and senescence were assessed. Finally, the expression levels of NF-κB signaling-related proteins p-NF-κB p65 and NF-κB p65 were detected using western blot analysis. The results showed that UCHL1 was downregulated in H2O2-treated HEI-OC1 cells. In addition, UCHL1 overexpression enhanced cell viability and promoted oxidative damage, apoptosis and senescence in H2O2-induced HEI-OC1 cells. Furthermore, Sp1 was upregulated in H2O2-treated HEI-OC1 cells. Additionally, luciferase reporter and ChIP assays demonstrated that Sp1 interacted with the UCHL1 promoter to inhibit UCHL1 transcription. Sp1 overexpression reversed the effect of UCHL1 overexpression on cell viability, oxidative stress, apoptosis, senescence and activation of the NF-κB signaling pathway in H2O2-exposed HEI-OC1 cells. Collectively, the results suggested that UCHL1 transcriptional suppression by Sp1 protected cochlear hair cells from H2O2-triggered senescence and oxidative damage.
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Affiliation(s)
- Lihua Li
- Department of Otorhinolaryngology, The Second Affiliated Hospital of Nanchang University, Nanchang, Jiangxi 330006, P.R. China
| | - Kai Xu
- Department of Otorhinolaryngology, The Second Affiliated Hospital of Nanchang University, Nanchang, Jiangxi 330006, P.R. China
| | - Xue Bai
- Department of Otorhinolaryngology, The Second Affiliated Hospital of Nanchang University, Nanchang, Jiangxi 330006, P.R. China
| | - Zhi Wang
- Department of Otorhinolaryngology, The Second Affiliated Hospital of Nanchang University, Nanchang, Jiangxi 330006, P.R. China
| | - Xiaoyan Tian
- Department of Otorhinolaryngology, The Second Affiliated Hospital of Nanchang University, Nanchang, Jiangxi 330006, P.R. China
| | - Xubo Chen
- Department of Otorhinolaryngology, The Second Affiliated Hospital of Nanchang University, Nanchang, Jiangxi 330006, P.R. China,Correspondence to: Dr Xubo Chen, Department of Otorhinolaryngology, The Second Affiliated Hospital of Nanchang University, 1 Minde Road, Nanchang, Jiangxi 330006, P.R. China
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10
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Sho C, Kawano K, Hou DX, Yoshimoto M, Okuno H. Ameliorative effect of the oil components derived from sweet potato shochu on impaired short-term memory in mice after amyloid β 25-35 injection. J Biosci Bioeng 2023; 135:54-62. [PMID: 36336574 DOI: 10.1016/j.jbiosc.2022.10.004] [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: 07/18/2022] [Revised: 09/20/2022] [Accepted: 10/04/2022] [Indexed: 11/05/2022]
Abstract
Sweet potato shochu oil is a by-product of shochu production and usually discarded although some physiological functions are considered. In this study, we investigated the effects of shochu oil on short-term memory using a murine model of spontaneous alternating behavior induced by the intracerebroventricular (ICV) administration of amyloid β25-35 (Aβ25-35). Mice were orally administered shochu oil for 15 days. Experiments with a Y-maze model revealed that the Aβ25-35 caused a significant decrease in spontaneous alternation behavior, and supplementation with shochu oil significantly improved this behavior. DNA microarray analysis revealed that the administration of shochu oil downregulated the expression of S100a9 and Ptgs2, which reportedly exacerbate amyloid β deposition in Alzheimer's disease. The administration of shochu oil upregulated the expression of Dnaja1 and PP2A, which is typically downregulated in Alzheimer's disease. These data suggest that shochu oil possible ameliorates on impaired short-term memory in mice after amyloid β25-35 injection, as indicated by its effects on improving spontaneous alternation behavior and modulating the expressions of related genes.
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Affiliation(s)
- Cho Sho
- Kirishima Shuzo Co., Ltd., 4-28-1 Shimokawahigashi, Miyakonojo, Miyazaki 885-8588, Japan.
| | - Kuniaki Kawano
- Kirishima Shuzo Co., Ltd., 4-28-1 Shimokawahigashi, Miyakonojo, Miyazaki 885-8588, Japan
| | - De-Xing Hou
- The United Graduate School of Agricultural Sciences, Kagoshima University, 1-21-24 Korimoto, Kagoshima 890-0065, Japan
| | - Makoto Yoshimoto
- MY Food Development Research Institute, 109-3 ichimanjyo, Miyakonojo, Miyazaki 885-0041, Japan
| | - Hironori Okuno
- Kirishima Shuzo Co., Ltd., 4-28-1 Shimokawahigashi, Miyakonojo, Miyazaki 885-8588, Japan
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11
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Guo J, Huang X, Dou L, Yan M, Shen T, Tang W, Li J. Aging and aging-related diseases: from molecular mechanisms to interventions and treatments. Signal Transduct Target Ther 2022; 7:391. [PMID: 36522308 PMCID: PMC9755275 DOI: 10.1038/s41392-022-01251-0] [Citation(s) in RCA: 248] [Impact Index Per Article: 124.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2022] [Revised: 11/03/2022] [Accepted: 11/10/2022] [Indexed: 12/23/2022] Open
Abstract
Aging is a gradual and irreversible pathophysiological process. It presents with declines in tissue and cell functions and significant increases in the risks of various aging-related diseases, including neurodegenerative diseases, cardiovascular diseases, metabolic diseases, musculoskeletal diseases, and immune system diseases. Although the development of modern medicine has promoted human health and greatly extended life expectancy, with the aging of society, a variety of chronic diseases have gradually become the most important causes of disability and death in elderly individuals. Current research on aging focuses on elucidating how various endogenous and exogenous stresses (such as genomic instability, telomere dysfunction, epigenetic alterations, loss of proteostasis, compromise of autophagy, mitochondrial dysfunction, cellular senescence, stem cell exhaustion, altered intercellular communication, deregulated nutrient sensing) participate in the regulation of aging. Furthermore, thorough research on the pathogenesis of aging to identify interventions that promote health and longevity (such as caloric restriction, microbiota transplantation, and nutritional intervention) and clinical treatment methods for aging-related diseases (depletion of senescent cells, stem cell therapy, antioxidative and anti-inflammatory treatments, and hormone replacement therapy) could decrease the incidence and development of aging-related diseases and in turn promote healthy aging and longevity.
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Affiliation(s)
- Jun Guo
- grid.506261.60000 0001 0706 7839The Key Laboratory of Geriatrics, Beijing Institute of Geriatrics, Institute of Geriatric Medicine, Chinese Academy of Medical Sciences, Beijing Hospital/National Center of Gerontology of National Health Commission, Beijing, 100730 China
| | - Xiuqing Huang
- grid.506261.60000 0001 0706 7839The Key Laboratory of Geriatrics, Beijing Institute of Geriatrics, Institute of Geriatric Medicine, Chinese Academy of Medical Sciences, Beijing Hospital/National Center of Gerontology of National Health Commission, Beijing, 100730 China
| | - Lin Dou
- grid.506261.60000 0001 0706 7839The Key Laboratory of Geriatrics, Beijing Institute of Geriatrics, Institute of Geriatric Medicine, Chinese Academy of Medical Sciences, Beijing Hospital/National Center of Gerontology of National Health Commission, Beijing, 100730 China
| | - Mingjing Yan
- grid.506261.60000 0001 0706 7839The Key Laboratory of Geriatrics, Beijing Institute of Geriatrics, Institute of Geriatric Medicine, Chinese Academy of Medical Sciences, Beijing Hospital/National Center of Gerontology of National Health Commission, Beijing, 100730 China
| | - Tao Shen
- grid.506261.60000 0001 0706 7839The Key Laboratory of Geriatrics, Beijing Institute of Geriatrics, Institute of Geriatric Medicine, Chinese Academy of Medical Sciences, Beijing Hospital/National Center of Gerontology of National Health Commission, Beijing, 100730 China
| | - Weiqing Tang
- grid.506261.60000 0001 0706 7839The Key Laboratory of Geriatrics, Beijing Institute of Geriatrics, Institute of Geriatric Medicine, Chinese Academy of Medical Sciences, Beijing Hospital/National Center of Gerontology of National Health Commission, Beijing, 100730 China
| | - Jian Li
- grid.506261.60000 0001 0706 7839The Key Laboratory of Geriatrics, Beijing Institute of Geriatrics, Institute of Geriatric Medicine, Chinese Academy of Medical Sciences, Beijing Hospital/National Center of Gerontology of National Health Commission, Beijing, 100730 China
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12
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Wang C, Qiu J, Li G, Wang J, Liu D, Chen L, Song X, Cui L, Sun Y. Application and prospect of quasi-targeted metabolomics in age-related hearing loss. Hear Res 2022; 424:108604. [PMID: 36116178 DOI: 10.1016/j.heares.2022.108604] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/22/2022] [Revised: 08/28/2022] [Accepted: 09/03/2022] [Indexed: 11/04/2022]
Abstract
Age-related hearing loss (ARHL) is a common sensory deficit in the elderly, which seriously affects physical and mental health. Therefore, understanding its underlying molecular mechanisms and taking interventions to treat ARHL are urgently needed. In our study, cochlea of 4-week-old C57BL/6 mice as the Youth group (n = 6) and 48-week-old cochlea as the Old group (n = 6) were subjected to quasi-targeted metabolomics analysis by Ultra high performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS). In total, 208 differential metabolites were identified in 12 cochlea samples, which highlighted the following discriminant compounds: tryptophan, piperidine, methionine, L-arginine, histamine, serotonin, acetylcholine, and 4-aminobutyric acid. Differentially expressed metabolites were identified which were involved in KEGG pathways related to the digestion and absorption of oxidative stress associated amino acids, Synaptic vesicle cycle of serotonin, Pantothenate and CoA Biosynthesis. These findings are a first step toward elucidating the pathophysiological pathways involved in the etiology of ARHL and provide the possibility to further explore the mechanisms of ARHL using metabolomic analysis.
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Affiliation(s)
- Chen Wang
- School of Clinical Medicine, Weifang Medical University, Baotong West Street 7166, Weifang, China; Department of Otorhinolaryngology, Head and Neck Surgery, Yantai Yuhuangding Hospital, Qingdao University, 20 East Yuhuangding Road, Yantai, Shandong 264000, China; Shandong Provincial Clinical Research Center for Otorhinolaryngologic Diseases, 20 East Yuhuangding Road, Yantai, Shandong 264000, China
| | - Jingjing Qiu
- Department of Otorhinolaryngology, Head and Neck Surgery, Yantai Yuhuangding Hospital, Qingdao University, 20 East Yuhuangding Road, Yantai, Shandong 264000, China; Shandong Provincial Clinical Research Center for Otorhinolaryngologic Diseases, 20 East Yuhuangding Road, Yantai, Shandong 264000, China
| | - Guangjin Li
- School of Clinical Medicine, Weifang Medical University, Baotong West Street 7166, Weifang, China; Department of Otorhinolaryngology, Head and Neck Surgery, Yantai Yuhuangding Hospital, Qingdao University, 20 East Yuhuangding Road, Yantai, Shandong 264000, China; Shandong Provincial Clinical Research Center for Otorhinolaryngologic Diseases, 20 East Yuhuangding Road, Yantai, Shandong 264000, China
| | - Junxin Wang
- School of Clinical Medicine, Weifang Medical University, Baotong West Street 7166, Weifang, China; Department of Otorhinolaryngology, Head and Neck Surgery, Yantai Yuhuangding Hospital, Qingdao University, 20 East Yuhuangding Road, Yantai, Shandong 264000, China; Shandong Provincial Clinical Research Center for Otorhinolaryngologic Diseases, 20 East Yuhuangding Road, Yantai, Shandong 264000, China
| | - Dawei Liu
- Department of Otorhinolaryngology, Head and Neck Surgery, Yantai Yuhuangding Hospital, Qingdao University, 20 East Yuhuangding Road, Yantai, Shandong 264000, China; Shandong Provincial Clinical Research Center for Otorhinolaryngologic Diseases, 20 East Yuhuangding Road, Yantai, Shandong 264000, China
| | - Liang Chen
- Department of Otorhinolaryngology, Head and Neck Surgery, Yantai Yuhuangding Hospital, Qingdao University, 20 East Yuhuangding Road, Yantai, Shandong 264000, China; Shandong Provincial Clinical Research Center for Otorhinolaryngologic Diseases, 20 East Yuhuangding Road, Yantai, Shandong 264000, China
| | - Xicheng Song
- Department of Otorhinolaryngology, Head and Neck Surgery, Yantai Yuhuangding Hospital, Qingdao University, 20 East Yuhuangding Road, Yantai, Shandong 264000, China; Shandong Provincial Clinical Research Center for Otorhinolaryngologic Diseases, 20 East Yuhuangding Road, Yantai, Shandong 264000, China
| | - Limei Cui
- Department of Otorhinolaryngology, Head and Neck Surgery, Yantai Yuhuangding Hospital, Qingdao University, 20 East Yuhuangding Road, Yantai, Shandong 264000, China; Shandong Provincial Clinical Research Center for Otorhinolaryngologic Diseases, 20 East Yuhuangding Road, Yantai, Shandong 264000, China.
| | - Yan Sun
- Department of Otorhinolaryngology, Head and Neck Surgery, Yantai Yuhuangding Hospital, Qingdao University, 20 East Yuhuangding Road, Yantai, Shandong 264000, China; Shandong Provincial Clinical Research Center for Otorhinolaryngologic Diseases, 20 East Yuhuangding Road, Yantai, Shandong 264000, China.
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13
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Guo L, Wang W, Song W, Cao H, Tian H, Wang Z, Ren J, Ning F, Zhang D, Duan H. Genome-wide DNA methylation analysis of middle-aged and elderly monozygotic twins with age-related hearing loss in Qingdao, China. Gene 2022; 849:146918. [PMID: 36179964 DOI: 10.1016/j.gene.2022.146918] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2022] [Revised: 09/20/2022] [Accepted: 09/21/2022] [Indexed: 11/17/2022]
Abstract
OBJECTIVE To explore the differences in DNA methylation associated with age-related hearing loss in a study of 57 twin pairs from China. DESIGN Monozygotic twins were identified through the Qingdao Twin Registration system. The median age of participants was >50 years. Their hearing thresholds were measured using a multilevel pure-tone audiometry assessment. The pure-tone audiometry was calculated at low frequencies (0.5, 1.0, and 2.0 kHz), speech frequencies (0.5, 1.0, 2.0, and 4.0kHz), and high frequencies (4.0 and 8 kHz). The CpG sites were tested using a linear mixed-effects model, and the function of the cis-regulatory regions and ontological enrichments were predicted using the online Genomic Regions Enrichment of Annotations Tool. The differentially methylated regions were identified using a comb-p python library approach. RESULTS In each of the PTA categories (low-, speech-, high-frequency), age-related hearing loss was detected in 25.9%, 19.3%, and 52.8% of participants. In the low-, speech- and high-frequency categories we identified 18, 42, and 12 individual CpG sites and 6, 11, and 6 differentially methylated regions. The CpG site located near DUSP4 had the strongest association with low- and speech-frequency, while the strongest association with high-frequency was near C21orf58. We identified associations of ALG10 with high-frequency hearing, C3 and LCK with low- and speech-frequency hearing, and GBX2 with low-frequency hearing. Top pathways that may be related to hearing, such as the Notch signaling pathway, were also identified. CONCLUSION Our study is the first of its kind to identify these genes and their associated with DNA methylation may play essential roles in the hearing process. The results of our epigenome-wide association study on twins clarify the complex mechanisms underlying age-related hearing loss.
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Affiliation(s)
- Longzi Guo
- Department of Epidemiology and Health Statistics, Public Health College, Qingdao University, Qingdao, China
| | - Weijing Wang
- Department of Epidemiology and Health Statistics, Public Health College, Qingdao University, Qingdao, China
| | - Wanxue Song
- Qingdao Maternal and Child Health and Family Planning Service Center, Qingdao, China
| | - Hainan Cao
- Department of Otorhinolaryngology, Qingdao Municipal Hospital, Qingdao, China
| | - Huimin Tian
- Department of Epidemiology and Health Statistics, Public Health College, Qingdao University, Qingdao, China
| | - Zhaoguo Wang
- Qingdao Municipal Center for Disease Control and Prevention, Qingdao, China
| | - Jifeng Ren
- Department of Epidemiology and Health Statistics, Public Health College, Qingdao University, Qingdao, China
| | - Feng Ning
- Qingdao Municipal Center for Disease Control and Prevention, Qingdao, China
| | - Dongfeng Zhang
- Department of Epidemiology and Health Statistics, Public Health College, Qingdao University, Qingdao, China
| | - Haiping Duan
- Qingdao Municipal Center for Disease Control and Prevention, Qingdao, China.
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Age-Related Hearing Loss: The Link between Inflammaging, Immunosenescence, and Gut Dysbiosis. Int J Mol Sci 2022; 23:ijms23137348. [PMID: 35806352 PMCID: PMC9266910 DOI: 10.3390/ijms23137348] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2022] [Revised: 06/30/2022] [Accepted: 06/30/2022] [Indexed: 12/12/2022] Open
Abstract
This article provides a theoretical overview of the association between age-related hearing loss (ARHL), immune system ageing (immunosenescence), and chronic inflammation. ARHL, or presbyacusis, is the most common sensory disability that significantly reduces the quality of life and has a high economic impact. This disorder is linked to genetic risk factors but is also influenced by a lifelong cumulative effect of environmental stressors, such as noise, otological diseases, or ototoxic drugs. Age-related hearing loss and other age-related disorders share common mechanisms which often converge on low-grade chronic inflammation known as “inflammaging”. Various stimuli can sustain inflammaging, including pathogens, cell debris, nutrients, and gut microbiota. As a result of ageing, the immune system can become defective, leading to the accumulation of unresolved inflammatory processes in the body. Gut microbiota plays a central role in inflammaging because it can release inflammatory mediators and crosstalk with other organ systems. A proinflammatory gut environment associated with ageing could result in a leaky gut and the translocation of bacterial metabolites and inflammatory mediators to distant organs via the systemic circulation. Here, we postulate that inflammaging, as a result of immunosenescence and gut dysbiosis, accelerates age-related cochlear degeneration, contributing to the development of ARHL. Age-dependent gut dysbiosis was included as a hypothetical link that should receive more attention in future studies.
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15
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Seicol BJ, Lin S, Xie R. Age-Related Hearing Loss Is Accompanied by Chronic Inflammation in the Cochlea and the Cochlear Nucleus. Front Aging Neurosci 2022; 14:846804. [PMID: 35418849 PMCID: PMC8995794 DOI: 10.3389/fnagi.2022.846804] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2021] [Accepted: 03/07/2022] [Indexed: 12/24/2022] Open
Abstract
Age-related hearing loss (ARHL) is a major hearing impairment characterized by pathological changes in both the peripheral and central auditory systems. Low-grade inflammation was observed in the cochlea of deceased human subjects with ARHL and animal models of early onset ARHL, which suggests that inflammation contributes to the development of ARHL. However, it remains elusive how chronic inflammation progresses during normal aging in the cochlea, and especially the accompanying changes of neuroinflammation in the central auditory system. To address this, we investigated chronic inflammation in both the cochlea and the cochlear nucleus (CN) of CBA/CaJ mice, an inbred mouse strain that undergoes normal aging and develops human, like-late-onset ARHL. Using immunohistochemistry, confocal microscopy, and quantitative image processing, we measured the accumulation and activation of macrophages in the cochlea and microglia in the CN using their shared markers: ionized calcium binding adaptor molecule 1 (Iba1) and CD68—a marker of phagocytic activity. We found progressive increases in the area covered by Iba1-labeled macrophages and enhanced CD68 staining in the osseous spiral lamina of the cochlea that correlated with elevated ABR threshold across the lifespan. During the process, we further identified significant increases in microglial activation and C1q deposition in the CN, indicating increased neuroinflammation and complement activation in the central auditory system. Our study suggests that during normal aging, chronic inflammation occurs in both the peripheral and the central auditory system, which may contribute in coordination to the development of ARHL.
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Affiliation(s)
- Benjamin J. Seicol
- Department of Otolaryngology—Head and Neck Surgery, The Ohio State University, Columbus, OH, United States
- Department of Neuroscience, The Ohio State University, Columbus, OH, United States
| | - Shengyin Lin
- Department of Otolaryngology—Head and Neck Surgery, The Ohio State University, Columbus, OH, United States
| | - Ruili Xie
- Department of Otolaryngology—Head and Neck Surgery, The Ohio State University, Columbus, OH, United States
- Department of Neuroscience, The Ohio State University, Columbus, OH, United States
- *Correspondence: Ruili Xie
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16
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Transcriptome-Guided Identification of Drugs for Repurposing to Treat Age-Related Hearing Loss. Biomolecules 2022; 12:biom12040498. [PMID: 35454087 PMCID: PMC9028743 DOI: 10.3390/biom12040498] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2022] [Revised: 03/13/2022] [Accepted: 03/22/2022] [Indexed: 02/04/2023] Open
Abstract
Age-related hearing loss (ARHL) or presbycusis is a prevalent condition associated with social isolation, cognitive impairment, and dementia. Age-related changes in the cochlea, the auditory portion of the inner ear, are the primary cause of ARHL. Unfortunately, there are currently no pharmaceutical approaches to treat ARHL. To examine the biological processes underlying age-related changes in the cochlea and identify candidate drugs for rapid repurposing to treat ARHL, we utilized bulk RNA sequencing to obtain transcriptomes from the functional substructures of the cochlea—the sensorineural structures, including the organ of Corti and spiral ganglion neurons (OC/SGN) and the stria vascularis and spiral ligament (SV/SL)—in young (6-week-old) and old (2-year-old) C57BL/6 mice. Transcriptomic analyses revealed both overlapping and unique patterns of gene expression and gene enrichment between substructures and with ageing. Based on these age-related transcriptional changes, we queried the protein products of genes differentially expressed with ageing in DrugBank and identified 27 FDA/EMA-approved drugs that are suitable to be repurposed to treat ARHL. These drugs target the protein products of genes that are differentially expressed with ageing uniquely in either the OC/SGN or SV/SL and that interrelate diverse biological processes. Further transcriptomic analyses revealed that most genes differentially expressed with ageing in both substructures encode protein products that are promising drug target candidates but are, nevertheless, not yet linked to approved drugs. Thus, with this study, we apply a novel approach to characterize the druggable genetic landscape for ARHL and propose a list of drugs to test in pre-clinical studies as potential treatment options for ARHL.
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Chen P, Hao JJ, Li MW, Bai J, Guo YT, Liu Z, Shi P. Integrative Functional Transcriptomic Analyses Implicate Shared Molecular Circuits in Sensorineural Hearing Loss. Front Cell Neurosci 2022; 16:857344. [PMID: 35370561 PMCID: PMC8964368 DOI: 10.3389/fncel.2022.857344] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2022] [Accepted: 02/21/2022] [Indexed: 12/20/2022] Open
Abstract
Sensorineural hearing loss (SNHL) is referred to as the most common type of hearing loss and typically occurs when the inner ear or the auditory nerve is damaged. Aging, noise exposure, and ototoxic drugs represent three main causes of SNHL, leading to substantial similarities in pathophysiological characteristics of cochlear degeneration. Although the common molecular mechanisms are widely assumed to underlie these similarities, its validity lacks systematic examination. To address this question, we generated three SNHL mouse models from aging, noise exposure, and cisplatin ototoxicity, respectively. Through constructing gene co-expression networks for the cochlear transcriptome data across different hearing-damaged stages, the three models are found to significantly correlate with each other in multiple gene co-expression modules that implicate distinct biological functions, including apoptosis, immune, inflammation, and ion transport. Bioinformatics analyses reveal several potential hub regulators, such as IL1B and CCL2, both of which are verified to contribute to apoptosis accompanied by the increase of (ROS) in in vitro model system. Our findings disentangle the shared molecular circuits across different types of SNHL, providing potential targets for the broad effective therapeutic agents in SNHL.
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Affiliation(s)
- Peng Chen
- State Key Laboratory of Genetic Resources and Evolution, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming, China
- Kunming College of Life Science, University of Chinese Academy of Sciences, Kunming, China
| | - Jun-Jun Hao
- State Key Laboratory of Genetic Resources and Evolution, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming, China
| | - Meng-Wen Li
- State Key Laboratory of Genetic Resources and Evolution, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming, China
| | - Jing Bai
- State Key Laboratory of Genetic Resources and Evolution, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming, China
- School of Future Technology, University of Chinese Academy of Sciences, Beijing, China
| | - Yuan-Ting Guo
- State Key Laboratory of Genetic Resources and Evolution, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming, China
- Kunming College of Life Science, University of Chinese Academy of Sciences, Kunming, China
| | - Zhen Liu
- State Key Laboratory of Genetic Resources and Evolution, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming, China
- *Correspondence: Zhen Liu,
| | - Peng Shi
- State Key Laboratory of Genetic Resources and Evolution, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming, China
- School of Future Technology, University of Chinese Academy of Sciences, Beijing, China
- Center for Excellence in Animal Evolution and Genetics, Chinese Academy of Sciences, Kunming, China
- Peng Shi,
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18
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Age-related Activation of Cyclic GMP-AMP synthase-Stimulator of Interferon Genes Signaling in the Auditory System is Associated with Presbycusis in C57BL/6J Male Mice. Neuroscience 2022; 481:73-84. [PMID: 34848262 DOI: 10.1016/j.neuroscience.2021.11.031] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2021] [Revised: 10/29/2021] [Accepted: 11/20/2021] [Indexed: 11/21/2022]
Abstract
Presbycusis, or age-related hearing loss (ARHL), is primarily associated with sensory or transduction nerve cell degeneration in the peripheral and/or central auditory systems. During aging, the auditory system shows mitochondrial dysfunction and increased inflammatory responses. Mitochondrial dysfunction promotes leakage of mitochondrial DNA (mtDNA) into the cytosol, which activates the cyclic GMP-AMP synthase (cGAS)-stimulator of interferon genes (STING) pathway to induce type I interferon and inflammatory responses. However, whether this pathway is involved in the occurrence and development of ARHL is unknown. This study aimed to determine whether there are age-related changes in the levels of cytosolic mtDNA and cGAS-STING pathway activation in the auditory pathway and to explore their relationship with ARHL. The results showed that cGAS-positive immunoreactive cells were observed in the cochlea, inferior colliculus, and auditory cortex. Levels of cytosolic mtDNA, cGAS, STING, phosphorylated interferon regulatory factor 3, and cytokines were significantly increased in the cochlea, inferior colliculus, and auditory cortex of 6-, 9-, and 12-month-old mice compared with 3-month-old mice. These findings suggested that cytosolic mtDNA may play an important role in the pathogenesis of ARHL by activating cGAS-STING-mediated type I interferon and inflammatory responses.
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19
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Uraguchi K, Maeda Y, Takahara J, Omichi R, Fujimoto S, Kariya S, Nishizaki K, Ando M. Upregulation of a nuclear factor-kappa B-interacting immune gene network in mice cochleae with age-related hearing loss. PLoS One 2021; 16:e0258977. [PMID: 34679122 PMCID: PMC8535356 DOI: 10.1371/journal.pone.0258977] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2021] [Accepted: 10/09/2021] [Indexed: 12/15/2022] Open
Abstract
Epidemiological data suggest that inflammation and innate immunity play significant roles in the pathogenesis of age-related hearing loss (ARHL) in humans. In this mouse study, real-time RT-PCR array targeting 84 immune-related genes revealed that the expressions of 40 genes (47.6%) were differentially regulated with greater than a twofold change in 12-month-old cochleae with ARHL relative to young control mice, 33 (39.3%) of which were upregulated. These differentially regulated genes (DEGs) were involved in functional pathways for cytokine–cytokine receptor interaction, chemokine signaling, TNF signaling, and Toll-like receptor signaling. An NF-κB subunit, Nfkb1, was upregulated in aged cochleae, and bioinformatic analyses predicted that NF-κB would interact with the genomic regulatory regions of eight upregulated DEGs, including Tnf and Ptgs2. In aging cochleae, major proinflammatory molecules, IL1B and IL18rap, were upregulated by 6 months of age and thereafter. Remarkable upregulations of seven immune-related genes (Casp1, IL18r1, IL1B, Card9, Clec4e, Ifit1, and Tlr9) occurred at an advanced stage (between 9 and 12 months of age) of ARHL. Immunohistochemistry analysis of cochlear sections from the 12-month-old mice indicated that IL-18r1 and IL-1B were localized to the spiral ligament, spiral limbus, and organ of Corti. The two NF-κB-interacting inflammatory molecules, TNFα and PTGS2, immunolocalized ubiquitously in cochlear structures, including the lateral wall (the stria vascularis and spiral ligament), in the histological sections of aged cochleae. IBA1-positive macrophages were observed in the stria vascularis and spiral ligament in aged mice. Therefore, inflammatory and immune reactions are modulated in aged cochlear tissues with ARHL.
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Affiliation(s)
- Kensuke Uraguchi
- Department of Otolaryngology- Head and Neck Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama, Japan
| | - Yukihide Maeda
- Department of Otolaryngology- Head and Neck Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama, Japan
- * E-mail:
| | - Junko Takahara
- Department of Otolaryngology- Head and Neck Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama, Japan
| | - Ryotaro Omichi
- Department of Otolaryngology- Head and Neck Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama, Japan
| | - Shohei Fujimoto
- Department of Otolaryngology- Head and Neck Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama, Japan
| | - Shin Kariya
- Department of Otolaryngology- Head and Neck Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama, Japan
| | - Kazunori Nishizaki
- Department of Otolaryngology- Head and Neck Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama, Japan
| | - Mizuo Ando
- Department of Otolaryngology- Head and Neck Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama, Japan
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20
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Bazard P, Pineros J, Frisina RD, Bauer MA, Acosta AA, Paganella LR, Borakiewicz D, Thivierge M, Mannering FL, Zhu X, Ding B. Cochlear Inflammaging in Relation to Ion Channels and Mitochondrial Functions. Cells 2021; 10:2761. [PMID: 34685743 PMCID: PMC8534887 DOI: 10.3390/cells10102761] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2021] [Revised: 10/06/2021] [Accepted: 10/12/2021] [Indexed: 12/20/2022] Open
Abstract
The slow accumulation of inflammatory biomarker levels in the body-also known as inflammaging-has been linked to a myriad of age-related diseases. Some of these include neurodegenerative conditions such as Parkinson's disease, obesity, type II diabetes, cardiovascular disease, and many others. Though a direct correlation has not been established, research connecting age-related hearing loss (ARHL)-the number one communication disorder and one of the most prevalent neurodegenerative diseases of our aged population-and inflammaging has gained interest. Research, thus far, has found that inflammatory markers, such as IL-6 and white blood cells, are associated with ARHL in humans and animals. Moreover, studies investigating ion channels and mitochondrial involvement have shown promising relationships between their functions and inflammaging in the cochlea. In this review, we summarize key findings in inflammaging within the auditory system, the involvement of ion channels and mitochondrial functions, and lastly discuss potential treatment options focusing on controlling inflammation as we age.
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Affiliation(s)
- Parveen Bazard
- Department of Medical Engineering, College of Engineering, University of South Florida, Tampa, FL 33620, USA; (P.B.); (J.P.); (M.A.B.); (A.A.A.); (L.R.P.); (D.B.); (M.T.); (X.Z.); (B.D.)
- Global Center for Hearing and Speech Research, University of South Florida, Tampa, FL 33612, USA;
| | - Jennifer Pineros
- Department of Medical Engineering, College of Engineering, University of South Florida, Tampa, FL 33620, USA; (P.B.); (J.P.); (M.A.B.); (A.A.A.); (L.R.P.); (D.B.); (M.T.); (X.Z.); (B.D.)
- Global Center for Hearing and Speech Research, University of South Florida, Tampa, FL 33612, USA;
| | - Robert D. Frisina
- Department of Medical Engineering, College of Engineering, University of South Florida, Tampa, FL 33620, USA; (P.B.); (J.P.); (M.A.B.); (A.A.A.); (L.R.P.); (D.B.); (M.T.); (X.Z.); (B.D.)
- Global Center for Hearing and Speech Research, University of South Florida, Tampa, FL 33612, USA;
- Department Communication Sciences and Disorders, College of Behavioral & Communication Sciences, Tampa, FL 33620, USA
- Morsani College of Medicine, University of South Florida, Tampa, FL 33620, USA
| | - Mark A. Bauer
- Department of Medical Engineering, College of Engineering, University of South Florida, Tampa, FL 33620, USA; (P.B.); (J.P.); (M.A.B.); (A.A.A.); (L.R.P.); (D.B.); (M.T.); (X.Z.); (B.D.)
- Global Center for Hearing and Speech Research, University of South Florida, Tampa, FL 33612, USA;
| | - Alejandro A. Acosta
- Department of Medical Engineering, College of Engineering, University of South Florida, Tampa, FL 33620, USA; (P.B.); (J.P.); (M.A.B.); (A.A.A.); (L.R.P.); (D.B.); (M.T.); (X.Z.); (B.D.)
- Global Center for Hearing and Speech Research, University of South Florida, Tampa, FL 33612, USA;
| | - Lauren R. Paganella
- Department of Medical Engineering, College of Engineering, University of South Florida, Tampa, FL 33620, USA; (P.B.); (J.P.); (M.A.B.); (A.A.A.); (L.R.P.); (D.B.); (M.T.); (X.Z.); (B.D.)
- Global Center for Hearing and Speech Research, University of South Florida, Tampa, FL 33612, USA;
| | - Dominika Borakiewicz
- Department of Medical Engineering, College of Engineering, University of South Florida, Tampa, FL 33620, USA; (P.B.); (J.P.); (M.A.B.); (A.A.A.); (L.R.P.); (D.B.); (M.T.); (X.Z.); (B.D.)
- Global Center for Hearing and Speech Research, University of South Florida, Tampa, FL 33612, USA;
| | - Mark Thivierge
- Department of Medical Engineering, College of Engineering, University of South Florida, Tampa, FL 33620, USA; (P.B.); (J.P.); (M.A.B.); (A.A.A.); (L.R.P.); (D.B.); (M.T.); (X.Z.); (B.D.)
- Morsani College of Medicine, University of South Florida, Tampa, FL 33620, USA
| | - Freyda L. Mannering
- Global Center for Hearing and Speech Research, University of South Florida, Tampa, FL 33612, USA;
- Morsani College of Medicine, University of South Florida, Tampa, FL 33620, USA
| | - Xiaoxia Zhu
- Department of Medical Engineering, College of Engineering, University of South Florida, Tampa, FL 33620, USA; (P.B.); (J.P.); (M.A.B.); (A.A.A.); (L.R.P.); (D.B.); (M.T.); (X.Z.); (B.D.)
- Global Center for Hearing and Speech Research, University of South Florida, Tampa, FL 33612, USA;
| | - Bo Ding
- Department of Medical Engineering, College of Engineering, University of South Florida, Tampa, FL 33620, USA; (P.B.); (J.P.); (M.A.B.); (A.A.A.); (L.R.P.); (D.B.); (M.T.); (X.Z.); (B.D.)
- Global Center for Hearing and Speech Research, University of South Florida, Tampa, FL 33612, USA;
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21
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Paplou V, Schubert NMA, Pyott SJ. Age-Related Changes in the Cochlea and Vestibule: Shared Patterns and Processes. Front Neurosci 2021; 15:680856. [PMID: 34539328 PMCID: PMC8446668 DOI: 10.3389/fnins.2021.680856] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2021] [Accepted: 07/20/2021] [Indexed: 12/16/2022] Open
Abstract
Both age-related hearing loss (ARHL) and age-related loss in vestibular function (ARVL) are prevalent conditions with deleterious consequences on the health and quality of life. Age-related changes in the inner ear are key contributors to both conditions. The auditory and vestibular systems rely on a shared sensory organ - the inner ear - and, like other sensory organs, the inner ear is susceptible to the effects of aging. Despite involvement of the same sensory structure, ARHL and ARVL are often considered separately. Insight essential for the development of improved diagnostics and treatments for both ARHL and ARVL can be gained by careful examination of their shared and unique pathophysiology in the auditory and vestibular end organs of the inner ear. To this end, this review begins by comparing the prevalence patterns of ARHL and ARVL. Next, the normal and age-related changes in the structure and function of the auditory and vestibular end organs are compared. Then, the contributions of various molecular mechanisms, notably inflammaging, oxidative stress, and genetic factors, are evaluated as possible common culprits that interrelate pathophysiology in the cochlea and vestibular end organs as part of ARHL and ARVL. A careful comparison of these changes reveals that the patterns of pathophysiology show similarities but also differences both between the cochlea and vestibular end organs and among the vestibular end organs. Future progress will depend on the development and application of new research strategies and the integrated investigation of ARHL and ARVL using both clinical and animal models.
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Affiliation(s)
- Vasiliki Paplou
- Department of Otorhinolaryngology and Head/Neck Surgery, University of Groningen, University Medical Center Groningen, Groningen, Netherlands
| | - Nick M A Schubert
- Department of Otorhinolaryngology and Head/Neck Surgery, University of Groningen, University Medical Center Groningen, Groningen, Netherlands.,Research School of Behavioural and Cognitive Neurosciences, Graduate School of Medical Sciences, University of Groningen, Groningen, Netherlands
| | - Sonja J Pyott
- Department of Otorhinolaryngology and Head/Neck Surgery, University of Groningen, University Medical Center Groningen, Groningen, Netherlands.,Research School of Behavioural and Cognitive Neurosciences, Graduate School of Medical Sciences, University of Groningen, Groningen, Netherlands
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22
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Hough K, Verschuur CA, Cunningham C, Newman TA. Macrophages in the cochlea; an immunological link between risk factors and progressive hearing loss. Glia 2021; 70:219-238. [PMID: 34536249 DOI: 10.1002/glia.24095] [Citation(s) in RCA: 28] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2021] [Revised: 09/08/2021] [Accepted: 09/09/2021] [Indexed: 02/06/2023]
Abstract
Macrophages are abundant in the cochlea; however, their role in hearing loss is not well understood. Insults to the cochlea, such as noise or insertion of a cochlear implant, cause an inflammatory response, which includes activation of tissue-resident macrophages. Activation is characterized by changes in macrophage morphology, mediator expression, and distribution. Evidence from other organs shows activated macrophages can become primed, whereby subsequent insults cause an elevated inflammatory response. Primed macrophages in brain pathologies respond to circulating inflammatory mediators by disproportionate synthesis of inflammatory mediators. This signaling occurs behind an intact blood-brain barrier, similar to the blood-labyrinth barrier in the cochlea. Local tissue damage can occur as the result of mediator release by activated macrophages. Damage is typically localized; however, if it is to structures with limited ability to repair, such as neurons or hair cells within the cochlea, it is feasible that this contributes to the progressive loss of function seen in hearing loss. We propose that macrophages in the cochlea link risk factors and hearing loss. Injury to the cochlea causes local macrophage activation that typically resolves. However, in susceptible individuals, some macrophages enter a primed state. Once primed, these macrophages can be further activated, as a consequence of circulating inflammatory molecules associated with common co-morbidities. Hypothetically, this would lead to further cochlear damage and loss of hearing. We review the evidence for the role of tissue-resident macrophages in the cochlea and propose that cochlear macrophages contribute to the trajectory of hearing loss and warrant further study.
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Affiliation(s)
- Kate Hough
- Faculty of Engineering and Physical Sciences, University of Southampton, Southampton, UK
| | - Carl A Verschuur
- Faculty of Engineering and Physical Sciences, Auditory Implant Centre, University of Southampton, Southampton, UK
| | - Colm Cunningham
- School of Biochemistry & Immunology, Trinity Biomedical Sciences Institute & Trinity College Institute of Neuroscience (TCIN), Dublin, Ireland
| | - Tracey A Newman
- Clinical and Experimental Sciences, Faculty of Medicine, IfLS, University of Southampton, Southampton, UK
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23
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Xue W, Tian Y, Xiong Y, Liu F, Feng Y, Chen Z, Yu D, Yin S. Transcriptomic Analysis Reveals an Altered Hcy Metabolism in the Stria Vascularis of the Pendred Syndrome Mouse Model. Neural Plast 2021; 2021:5585394. [PMID: 33959158 PMCID: PMC8075705 DOI: 10.1155/2021/5585394] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2021] [Revised: 02/19/2021] [Accepted: 04/01/2021] [Indexed: 12/13/2022] Open
Abstract
PURPOSE Slc26a4-/- mice exhibit severer defects in the development of the cochlea and develop deafness, while the underlying mechanisms responsible for these effects remain unclear. Our study was to investigate the potential mechanism linking SLC26A4 deficiency to hearing loss. MATERIALS AND METHODS RNA sequencing was applied to analyze the differential gene expression of the stria vascularis (SV) from wildtype and Slc26a4-/- mice. GO and KEGG pathway analysis were performed. Quantitative RT-PCR was applied to validate the expression of candidate genes affected by Slc26a4. ELISA and immunofluorescence technique were used to detect the homocysteine (Hcy) level in serum, brain, and SV, respectively. RESULTS 183 upregulated genes and 63 downregulated genes were identified in the SV associated with Slc26a4 depletion. Transcriptomic profiling revealed that Slc26a4 deficiency significantly affected the expression of genes associated with cell adhesion, transmembrane transport, and the biogenesis of multicellular organisms. The SV from Slc26a4-/- mice exhibited a higher expression of Bhmt mRNAs, as well as altered homocysteine (Hcy) metabolism. CONCLUSIONS The altered expression of Bhmt results in a dramatic change in multiple biochemical reactions and a disruption of nutrient homeostasis in the endolymph which may contribute to hearing loss of Slc26a4 knockout mouse.
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Affiliation(s)
- Wenyue Xue
- Department of Otolaryngology-Head and Neck Surgery, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, Shanghai, China
- Otolaryngology Institute of Shanghai Jiao Tong University, Shanghai, China
- Shanghai Key Laboratory of Sleep Disordered Breathing, Shanghai, China
| | - Yuxin Tian
- Department of Otolaryngology-Head and Neck Surgery, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, Shanghai, China
- Otolaryngology Institute of Shanghai Jiao Tong University, Shanghai, China
- Shanghai Key Laboratory of Sleep Disordered Breathing, Shanghai, China
| | - Yuanping Xiong
- Department of Otolaryngology-Head and Neck Surgery, First Affiliated Hospital of Nanchang University, Nanchang, Jiangxi, China
| | - Feng Liu
- Department of Otolaryngology-Head and Neck Surgery, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, Shanghai, China
- Otolaryngology Institute of Shanghai Jiao Tong University, Shanghai, China
- Shanghai Key Laboratory of Sleep Disordered Breathing, Shanghai, China
| | - Yanmei Feng
- Department of Otolaryngology-Head and Neck Surgery, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, Shanghai, China
- Otolaryngology Institute of Shanghai Jiao Tong University, Shanghai, China
- Shanghai Key Laboratory of Sleep Disordered Breathing, Shanghai, China
| | - Zhengnong Chen
- Department of Otolaryngology-Head and Neck Surgery, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, Shanghai, China
- Otolaryngology Institute of Shanghai Jiao Tong University, Shanghai, China
- Shanghai Key Laboratory of Sleep Disordered Breathing, Shanghai, China
| | - Dongzhen Yu
- Department of Otolaryngology-Head and Neck Surgery, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, Shanghai, China
- Otolaryngology Institute of Shanghai Jiao Tong University, Shanghai, China
- Shanghai Key Laboratory of Sleep Disordered Breathing, Shanghai, China
| | - Shankai Yin
- Department of Otolaryngology-Head and Neck Surgery, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, Shanghai, China
- Otolaryngology Institute of Shanghai Jiao Tong University, Shanghai, China
- Shanghai Key Laboratory of Sleep Disordered Breathing, Shanghai, China
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