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Carles L, Gibaja A, Scheper V, Alvarado JC, Almodovar C, Lenarz T, Juiz JM. Efficacy and Mechanisms of Antioxidant Compounds and Combinations Thereof against Cisplatin-Induced Hearing Loss in a Rat Model. Antioxidants (Basel) 2024; 13:761. [PMID: 39061830 PMCID: PMC11273477 DOI: 10.3390/antiox13070761] [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: 05/13/2024] [Revised: 06/13/2024] [Accepted: 06/19/2024] [Indexed: 07/28/2024] Open
Abstract
Cisplatin is an election chemotherapeutic agent used for many cancer treatments. Its cytotoxicity against neoplastic cells is mirrored by that taking place in healthy cells and tissues, resulting in serious adverse events. A very frequent one is ototoxicity, causing hearing loss which may permanently affect quality of life after successful oncologic treatments. Exacerbated oxidative stress is a main cytotoxic mechanism of cisplatin, including ototoxicity. Previous reports have shown antioxidant protection against cisplatin ototoxicity, but there is a lack of comparative studies on the otoprotectant activity and mechanism of antioxidant formulations. Here, we show evidence that a cocktail of vitamins A, C, and E along with Mg++ (ACEMg), previously shown to protect against noise-induced hearing loss, reverses auditory threshold shifts, promotes outer hair cell survival, and attenuates oxidative stress in the cochlea after cisplatin treatment, thus protecting against extreme cisplatin ototoxicity in rats. The addition of 500 mg N-acetylcysteine (NAC), which, administered individually, also shows significant attenuation of cisplatin ototoxicity, to the ACEMg formulation results in functional degradation of ACEMg otoprotection. Mg++ administered alone, as MgSO4, also prevents cisplatin ototoxicity, but in combination with 500 mg NAC, otoprotection is also greatly degraded. Increasing the dose of NAC to 1000 mg also results in dramatic loss of otoprotection activity compared with 500 mg NAC. These findings support that single antioxidants or antioxidant combinations, particularly ACEMg in this experimental series, have significant otoprotection efficacy against cisplatin ototoxicity. However, an excess of combined antioxidants and/or elevated doses, above a yet-to-be-defined "antioxidation threshold", results in unrecoverable redox imbalance with loss of otoprotectant activity.
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Grants
- PID2020-117266RB-C22-1, EXC 2177/1, ID:390895286, SBPLY/17/180501/000544. Ministerio de Ciencia Innovación, MCINN, Gobierno de España, Plan Estatal de I+D+i, PID2020-117266RB-C22-1, Cluster of Excellence "Hearing4All" EXC 2177/1, ID:390895286, part of the Germany´s Excellence Strategy of the German Research Foundation, DFG. Co
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Affiliation(s)
- Liliana Carles
- Instituto de Investigación en Discapacidades Neurológicas (IDINE), School of Medicine, Universidad de Castilla-La Mancha (UCLM), Campus in Albacete, 02008 Albacete, Spain; (L.C.); (A.G.); (J.C.A.)
- Department of Otolaryngology, University Hospital “Doce de Octubre”, 28041 Madrid, Spain;
| | - Alejandro Gibaja
- Instituto de Investigación en Discapacidades Neurológicas (IDINE), School of Medicine, Universidad de Castilla-La Mancha (UCLM), Campus in Albacete, 02008 Albacete, Spain; (L.C.); (A.G.); (J.C.A.)
| | - Verena Scheper
- Department of Otorhinolaryngology, Head and Neck Surgery, Hannover Medical School, 30625 Hannover, Germany; (V.S.); (T.L.)
- Cluster of Excellence “Hearing4all” of the German Research Foundation, DFG, 26111 Oldenburg, Germany
| | - Juan C. Alvarado
- Instituto de Investigación en Discapacidades Neurológicas (IDINE), School of Medicine, Universidad de Castilla-La Mancha (UCLM), Campus in Albacete, 02008 Albacete, Spain; (L.C.); (A.G.); (J.C.A.)
| | - Carlos Almodovar
- Department of Otolaryngology, University Hospital “Doce de Octubre”, 28041 Madrid, Spain;
| | - Thomas Lenarz
- Department of Otorhinolaryngology, Head and Neck Surgery, Hannover Medical School, 30625 Hannover, Germany; (V.S.); (T.L.)
- Cluster of Excellence “Hearing4all” of the German Research Foundation, DFG, 26111 Oldenburg, Germany
| | - José M. Juiz
- Instituto de Investigación en Discapacidades Neurológicas (IDINE), School of Medicine, Universidad de Castilla-La Mancha (UCLM), Campus in Albacete, 02008 Albacete, Spain; (L.C.); (A.G.); (J.C.A.)
- Department of Otorhinolaryngology, Head and Neck Surgery, Hannover Medical School, 30625 Hannover, Germany; (V.S.); (T.L.)
- Cluster of Excellence “Hearing4all” of the German Research Foundation, DFG, 26111 Oldenburg, Germany
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Zhou Y, Fang C, Yuan L, Guo M, Xu X, Shao A, Zhang A, Zhou D. Redox homeostasis dysregulation in noise-induced hearing loss: oxidative stress and antioxidant treatment. J Otolaryngol Head Neck Surg 2023; 52:78. [PMID: 38082455 PMCID: PMC10714662 DOI: 10.1186/s40463-023-00686-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2023] [Accepted: 12/04/2023] [Indexed: 12/18/2023] Open
Abstract
Noise exposure is an important cause of acquired hearing loss. Studies have found that noise exposure causes dysregulated redox homeostasis in cochlear tissue, which has been recognized as a signature feature of hearing loss. Oxidative stress plays a pivotal role in many diseases via very complex and diverse mechanisms and targets. Reactive oxygen species are products of oxidative stress that exert toxic effects on a variety of physiological activities and are considered significant in noise-induced hearing loss (NIHL). Endogenous cellular antioxidants can directly or indirectly counteract oxidative stress and regulate intracellular redox homeostasis, and exogenous antioxidants can complement and enhance this effect. Therefore, antioxidant therapy is considered a promising direction for NIHL treatment. However, drug experiments have been limited to animal models of NIHL, and these experiments and related observations are difficult to translate in humans; therefore, the mechanisms and true effects of these drugs need to be further analyzed. This review outlines the effects of oxidative stress in NIHL and discusses the main mechanisms and strategies of antioxidant treatment for NIHL.
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Affiliation(s)
- Yuhang Zhou
- Health Management Center, Tongde Hospital of Zhejiang Province, Hangzhou, China
- The First Clinical Medical College, Heilongjiang University of Chinese Medicine, Harbin, China
| | - Chaoyou Fang
- Department of Neurosurgery, Shanghai General Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China
| | - Ling Yuan
- Department of Neurosurgery, Shanghai General Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China
| | - Mengchen Guo
- Department of Dermatology, Tongji Hospital, School of Medicine, Tongji University, Shanghai, China
| | - Xinyi Xu
- School of Medicine, Ningbo University, Ningbo, China
| | - Anwen Shao
- Department of Neurosurgery, The Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, China
| | - Anke Zhang
- Department of Neurosurgery, The Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, China.
| | - Danyang Zhou
- Health Management Center, Tongde Hospital of Zhejiang Province, Hangzhou, China.
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Fátima Heredia R, Riestra-Ayora JI, Yanes-Díaz J, Thuissard Vasallo IJ, Andreu-Vázquez C, Sanz-Fernández R, Sánchez-Rodríguez C. Cocoa Polyphenols Prevent Age-Related Hearing Loss and Frailty in an In Vivo Model. Antioxidants (Basel) 2023; 12:1994. [PMID: 38001847 PMCID: PMC10669688 DOI: 10.3390/antiox12111994] [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: 10/02/2023] [Revised: 11/06/2023] [Accepted: 11/09/2023] [Indexed: 11/26/2023] Open
Abstract
Age-related hearing loss (ARHL) impairs the quality of life in elderly persons. ARHL is associated with comorbidities, such as depression, falls, or frailty. Frailty syndrome is related to poor health outcomes in old age. ARHL is a potentially modifiable risk factor for frailty. Oxidative stress has been proposed as a key factor underlying the onset and/or development of ARHL and frailty. Cocoa has high levels of polyphenols and provides many health benefits due to its antioxidant properties. Male and female C57Bl/6J mice were randomly assigned to two study groups: animals receiving a cocoa-supplemented diet and the other receiving a standard diet. Then, at the ages of 6, 14, and 22 months, hearing and frailty were measured in all mice. Auditory steady-state responses (ASSR) threshold shifts were measured to different frequencies. The frailty score was based on the "Valencia Score" adapted to the experimental animals. The total antioxidant capacity and total polyphenols in urine samples were also measured. Significant improvements in hearing ability are observed in the cocoa groups at 6, 14, and 22 months compared to the no cocoa group. The cocoa diet significantly retards the development of frailty in mice. Cocoa increases the concentration of polyphenols excreted in the urine, which increases the total antioxidant capacity. In conclusion, cocoa, due to its antioxidant properties, leads to significant protection against ARHL and frailty.
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Affiliation(s)
- Rosalía Fátima Heredia
- Department Clinical Analysis, Hospital Universitario de Getafe, Carretera de Toledo, km 12.500, 28905 Getafe, Madrid, Spain;
| | - Juan I. Riestra-Ayora
- Otolaryngology Department, Hospital Universitario de Getafe, Carretera de Toledo, km 12.500, 28905 Getafe, Madrid, Spain; (J.I.R.-A.); (J.Y.-D.); (R.S.-F.)
- Department of Medicine, Faculty of Biomedical and Health Sciences, Universidad Europea de Madrid, 28670 Villaviciosa de Odón, Madrid, Spain; (I.J.T.V.); (C.A.-V.)
| | - Joaquín Yanes-Díaz
- Otolaryngology Department, Hospital Universitario de Getafe, Carretera de Toledo, km 12.500, 28905 Getafe, Madrid, Spain; (J.I.R.-A.); (J.Y.-D.); (R.S.-F.)
| | - Israel John Thuissard Vasallo
- Department of Medicine, Faculty of Biomedical and Health Sciences, Universidad Europea de Madrid, 28670 Villaviciosa de Odón, Madrid, Spain; (I.J.T.V.); (C.A.-V.)
| | - Cristina Andreu-Vázquez
- Department of Medicine, Faculty of Biomedical and Health Sciences, Universidad Europea de Madrid, 28670 Villaviciosa de Odón, Madrid, Spain; (I.J.T.V.); (C.A.-V.)
| | - Ricardo Sanz-Fernández
- Otolaryngology Department, Hospital Universitario de Getafe, Carretera de Toledo, km 12.500, 28905 Getafe, Madrid, Spain; (J.I.R.-A.); (J.Y.-D.); (R.S.-F.)
- Department of Medicine, Faculty of Biomedical and Health Sciences, Universidad Europea de Madrid, 28670 Villaviciosa de Odón, Madrid, Spain; (I.J.T.V.); (C.A.-V.)
| | - Carolina Sánchez-Rodríguez
- Department of Medicine, Faculty of Biomedical and Health Sciences, Universidad Europea de Madrid, 28670 Villaviciosa de Odón, Madrid, Spain; (I.J.T.V.); (C.A.-V.)
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Paciello F, Ripoli C, Fetoni AR, Grassi C. Redox Imbalance as a Common Pathogenic Factor Linking Hearing Loss and Cognitive Decline. Antioxidants (Basel) 2023; 12:antiox12020332. [PMID: 36829891 PMCID: PMC9952092 DOI: 10.3390/antiox12020332] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2022] [Revised: 01/23/2023] [Accepted: 01/29/2023] [Indexed: 02/04/2023] Open
Abstract
Experimental and clinical data suggest a tight link between hearing and cognitive functions under both physiological and pathological conditions. Indeed, hearing perception requires high-level cognitive processes, and its alterations have been considered a risk factor for cognitive decline. Thus, identifying common pathogenic determinants of hearing loss and neurodegenerative disease is challenging. Here, we focused on redox status imbalance as a possible common pathological mechanism linking hearing and cognitive dysfunctions. Oxidative stress plays a critical role in cochlear damage occurring during aging, as well as in that induced by exogenous factors, including noise. At the same time, increased oxidative stress in medio-temporal brain regions, including the hippocampus, is a hallmark of neurodegenerative disorders like Alzheimer's disease. As such, antioxidant therapy seems to be a promising approach to prevent and/or counteract both sensory and cognitive neurodegeneration. Here, we review experimental evidence suggesting that redox imbalance is a key pathogenetic factor underlying the association between sensorineural hearing loss and neurodegenerative diseases. A greater understanding of the pathophysiological mechanisms shared by these two diseased conditions will hopefully provide relevant information to develop innovative and effective therapeutic strategies.
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Affiliation(s)
- Fabiola Paciello
- Department of Neuroscience, Università Cattolica del Sacro Cuore, 00168 Rome, Italy
- Fondazione Policlinico Universitario A. Gemelli IRCCS, 00168 Rome, Italy
| | - Cristian Ripoli
- Department of Neuroscience, Università Cattolica del Sacro Cuore, 00168 Rome, Italy
- Fondazione Policlinico Universitario A. Gemelli IRCCS, 00168 Rome, Italy
- Correspondence: ; Tel.: +39-0630154966
| | - Anna Rita Fetoni
- Unit of Audiology, Department of Neuroscience, Università degli Studi di Napoli Federico II, 80138 Naples, Italy
| | - Claudio Grassi
- Department of Neuroscience, Università Cattolica del Sacro Cuore, 00168 Rome, Italy
- Fondazione Policlinico Universitario A. Gemelli IRCCS, 00168 Rome, Italy
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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: 4] [Impact Index Per Article: 4.0] [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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Fuentes-Santamaría V, Alvarado JC, Mellado S, Melgar-Rojas P, Gabaldón-Ull MC, Cabanes-Sanchis JJ, Juiz JM. Age-Related Inflammation and Oxidative Stress in the Cochlea Are Exacerbated by Long-Term, Short-Duration Noise Stimulation. Front Aging Neurosci 2022; 14:853320. [PMID: 35450058 PMCID: PMC9016828 DOI: 10.3389/fnagi.2022.853320] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2022] [Accepted: 03/14/2022] [Indexed: 12/29/2022] Open
Abstract
We have previously reported that young adult rats exposed to daily, short-duration noise for extended time periods, develop accelerated presbycusis starting at 6 months of age. Auditory aging is associated with progressive hearing loss, cell deterioration, dysregulation of the antioxidant defense system, and chronic inflammation, among others. To further characterize cellular and molecular mechanisms at the crossroads between noise and age-related hearing loss (ARHL), 3-month-old rats were exposed to a noise-accelerated presbycusis (NAP) protocol and tested at 6 and 16 months of age, using auditory brainstem responses, Real-Time Reverse Transcription-Quantitative PCR (RT-qPCR) and immunocytochemistry. Chronic noise-exposure leading to permanent auditory threshold shifts in 6-month-old rats, resulted in impaired sodium/potassium activity, degenerative changes in the lateral wall and spiral ganglion, increased lipid peroxidation, and sustained cochlear inflammation with advancing age. Additionally, at 6 months, noise-exposed rats showed significant increases in the gene expression of antioxidant enzymes (superoxide dismutase 1/2, glutathione peroxidase 1, and catalase) and inflammation-associated molecules [ionized calcium binding adaptor molecule 1, interleukin-1 beta (IL-1β), and tumor necrosis factor-alpha]. The levels of IL-1β were upregulated in the spiral ganglion and spiral ligament, particularly in type IV fibrocytes; these cells showed decreased levels of connective tissue growth factor and increased levels of 4-hydroxynonenal. These data provide functional, structural and molecular evidence that age-noise interaction contributes to exacerbating presbycusis in young rats by leading to progressive dysfunction and early degeneration of cochlear cells and structures. These findings contribute to a better understanding of NAP etiopathogenesis, which is essential as it affects the life quality of young adults worldwide.
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Affiliation(s)
- Verónica Fuentes-Santamaría
- Instituto de Investigación en Discapacidades Neurológicas (IDINE), Albacete, Spain
- Facultad de Medicina, Universidad de Castilla-La Mancha, Albacete, Spain
| | - Juan Carlos Alvarado
- Instituto de Investigación en Discapacidades Neurológicas (IDINE), Albacete, Spain
- Facultad de Medicina, Universidad de Castilla-La Mancha, Albacete, Spain
| | - Susana Mellado
- Instituto de Investigación en Discapacidades Neurológicas (IDINE), Albacete, Spain
- Facultad de Medicina, Universidad de Castilla-La Mancha, Albacete, Spain
| | - Pedro Melgar-Rojas
- Instituto de Investigación en Discapacidades Neurológicas (IDINE), Albacete, Spain
- Facultad de Medicina, Universidad de Castilla-La Mancha, Albacete, Spain
| | - María Cruz Gabaldón-Ull
- Instituto de Investigación en Discapacidades Neurológicas (IDINE), Albacete, Spain
- Facultad de Medicina, Universidad de Castilla-La Mancha, Albacete, Spain
| | - José J. Cabanes-Sanchis
- Instituto de Investigación en Discapacidades Neurológicas (IDINE), Albacete, Spain
- Facultad de Medicina, Universidad de Castilla-La Mancha, Albacete, Spain
| | - José M. Juiz
- Instituto de Investigación en Discapacidades Neurológicas (IDINE), Albacete, Spain
- Facultad de Medicina, Universidad de Castilla-La Mancha, Albacete, Spain
- Department of Otolaryngology, Hannover Medical School, NIFE-VIANNA, Cluster of Excellence Hearing4all-German Research Foundation, Hanover, Germany
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Alvarado JC, Fuentes-Santamaría V, Juiz JM. Frailty Syndrome and Oxidative Stress as Possible Links Between Age-Related Hearing Loss and Alzheimer’s Disease. Front Neurosci 2022; 15:816300. [PMID: 35115905 PMCID: PMC8804094 DOI: 10.3389/fnins.2021.816300] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2021] [Accepted: 12/29/2021] [Indexed: 12/26/2022] Open
Abstract
As it is well known, a worldwide improvement in life expectancy has taken place. This has brought an increase in chronic pathologies associated with aging. Cardiovascular, musculoskeletal, psychiatric, and neurodegenerative conditions are common in elderly subjects. As far as neurodegenerative diseases are concerned dementias and particularly, Alzheimer’s disease (AD) occupy a central epidemiological position given their high prevalence and their profound negative impact on the quality of life and life expectancy. The amyloid cascade hypothesis partly explains the immediate cause of AD. However, limited therapeutical success based on this hypothesis suggests more complex remote mechanisms underlying its genesis and development. For instance, the strong association of AD with another irreversible neurodegenerative pathology, without curative treatment and complex etiology such as presbycusis, reaffirms the intricate nature of the etiopathogenesis of AD. Recently, oxidative stress and frailty syndrome have been proposed, independently, as key factors underlying the onset and/or development of AD and presbycusis. Therefore, the present review summarizes recent findings about the etiology of the above-mentioned neurodegenerative diseases, providing a critical view of the possible interplay among oxidative stress, frailty syndrome, AD and presbycusis, that may help to unravel the common mechanisms shared by both pathologies. This knowledge would help to design new possible therapeutic strategies that in turn, will improve the quality of life of these patients.
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Diet Quality and the Risk of Impaired Speech Reception Threshold in Noise: The UK Biobank cohort. Ear Hear 2021; 43:361-369. [PMID: 34320526 DOI: 10.1097/aud.0000000000001108] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
OBJECTIVE Previous studies have examined the association between several diet quality indexes and risk of hearing loss, based on self-reported information or on audiometry test, with inconsistent results. However, the impact of healthy diets on the capacity to listening in noise, a proxy of disability due to hearing loss, is unknown. This research assessed the prospective association between five diet quality indexes and the speech reception threshold in noise in the UK Biobank study. DESIGN Prospective cohort with 105,592 participants aged ≥40 years. At baseline, adherence to the Mediterranean Diet Adherence Screener, the alternate Mediterranean Diet score, the Dietary Approaches to Stop Hypertension, the Alternate Healthy Eating Index-2010, and the healthful Plant-Based Diet Index were assessed. Functional auditory capacity was measured with a digit triplet test, and impairment was defined as a speech reception threshold in noise >-3.5 dB in any physical exam during the follow-up. RESULTS Over a median follow-up of 3.2 (SD: 2.1) years, 1704 participants showed impaired speech reception threshold in noise. After adjusting for potential confounders, the hazard ratios (95% confidence interval) of impairment per 1-SD increase in the Mediterranean Diet Adherence Screener, alternate Mediterranean Diet score, Dietary Approaches to Stop Hypertension, Alternate Healthy Eating Index-2010 and healthful Plant-Based Diet Index scores were, respectively, 0.98 (0.94 to 1.03), 1.01 (0.96 to 1.06), 1.02 (0.97 to 1.07), 1.01 (0.96 to 1.06), and 1.00 (0.96 to 1.05). Results were similar when analyses were restricted to those >60 years, with British ethnicity, without chronic disease, without tinnitus or with optimal cognitive function. CONCLUSIONS Adherence to a healthy diet did not show an association with the speech reception threshold in noise. More research is needed to identify the impact of individual foods or nutrients on this outcome.
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Lampignano L, Quaranta N, Bortone I, Tirelli S, Zupo R, Castellana F, Donghia R, Guerra V, Griseta C, Pesole PL, Chieppa M, Logroscino G, Lozupone M, Cisternino AM, De Pergola G, Panza F, Giannelli G, Boeing H, Sardone R. Dietary Habits and Nutrient Intakes Are Associated to Age-Related Central Auditory Processing Disorder in a Cohort From Southern Italy. Front Aging Neurosci 2021; 13:629017. [PMID: 34025388 PMCID: PMC8134698 DOI: 10.3389/fnagi.2021.629017] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2020] [Accepted: 04/12/2021] [Indexed: 11/13/2022] Open
Abstract
Objectives Central auditory processing disorder (CAPD) commonly occurs in older age. However, few studies of a possible link between age-related CAPD and diet in an older population have been conducted. The objective of the present study was to investigate the relationship between eating habits and age-related CAPD in a population >65 years, using cross-sectional and retrospective data obtained in the same population-based study about 12 years ago. Methods We selected 734 participants (403 men) from a large population-based study. For age-related CAPD assessment, we used the Synthetic Sentence Identification with Ipsilateral Competitive Message test. Dietary habits were assessed by a Food Frequency Questionnaire. Associations between age-related CAPD and food groups/macro-and micronutrients were explored using adjusted logistic regression models. Results Age-related CAPD subjects consumed more dairy (111 vs. 98 g/d), olives and vegetable oil (63 vs. 52 g/d) and spirits (2 vs.1 g/d), and less fruits (536 vs. 651 g/d) in the cross-sectional analysis. Age-related CAPD subjects had a lower intake of potassium, vitamin C, and a higher fat intake. Further analyses identified dietary fiber as being inversely related to age-related CAPD. Discussion The present study provided evidence that the dietary hypotheses proposed for explaining the development of cognitive disorders in older age might also hold for age-related CAPD. Further data from other large and prospective population-based studies are needed for confirming these findings.
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Affiliation(s)
- Luisa Lampignano
- Unit of Research Methodology and Data Sciences for Population Health, "Salus in Apulia Study" National Institute of Gastroenterology "S. de Bellis" Research Hospital, Bari, Italy
| | - Nicola Quaranta
- Otolaryngology Unit, Department of Basic Medical Science, Neuroscience and Sense Organs, University of Bari Aldo Moro, Bari, Italy
| | - Ilaria Bortone
- Unit of Research Methodology and Data Sciences for Population Health, "Salus in Apulia Study" National Institute of Gastroenterology "S. de Bellis" Research Hospital, Bari, Italy
| | - Sarah Tirelli
- Unit of Research Methodology and Data Sciences for Population Health, "Salus in Apulia Study" National Institute of Gastroenterology "S. de Bellis" Research Hospital, Bari, Italy
| | - Roberta Zupo
- Unit of Research Methodology and Data Sciences for Population Health, "Salus in Apulia Study" National Institute of Gastroenterology "S. de Bellis" Research Hospital, Bari, Italy
| | - Fabio Castellana
- Unit of Research Methodology and Data Sciences for Population Health, "Salus in Apulia Study" National Institute of Gastroenterology "S. de Bellis" Research Hospital, Bari, Italy
| | - Rossella Donghia
- Data Analysis Unit, National Institute of Gastroenterology "S. de Bellis" Research Hospital, Bari, Italy
| | - Vito Guerra
- Data Analysis Unit, National Institute of Gastroenterology "S. de Bellis" Research Hospital, Bari, Italy
| | - Chiara Griseta
- Unit of Research Methodology and Data Sciences for Population Health, "Salus in Apulia Study" National Institute of Gastroenterology "S. de Bellis" Research Hospital, Bari, Italy
| | - Pasqua Letizia Pesole
- Laboratory of Clinical Pathology, National Institute of Gastroenterology "S. de Bellis" Research Hospital, Bari, Italy
| | - Marcello Chieppa
- National Institute of Gastroenterology "S. de Bellis" Research Hospital, Bari, Italy
| | - Giancarlo Logroscino
- Center for Neurodegenerative Diseases and the Aging Brain, University of Bari Aldo Moro, Bari, Italy.,Department of Clinical Research in Neurology, "Pia Fondazione Cardinale G. Panico," Lecce, Italy
| | - Madia Lozupone
- Center for Neurodegenerative Diseases and the Aging Brain, University of Bari Aldo Moro, Bari, Italy
| | - Anna Maria Cisternino
- Ambulatory of Clinical Nutrition, National Institute of Gastroenterology "S. de Bellis" Research Hospital, Bari, Italy
| | - Giovanni De Pergola
- Department of Biomedical Science and Human Oncology, School of Medicine, University of Bari Aldo Moro, Bari, Italy
| | - Francesco Panza
- Unit of Research Methodology and Data Sciences for Population Health, "Salus in Apulia Study" National Institute of Gastroenterology "S. de Bellis" Research Hospital, Bari, Italy
| | - Gianluigi Giannelli
- Unit of Research Methodology and Data Sciences for Population Health, "Salus in Apulia Study" National Institute of Gastroenterology "S. de Bellis" Research Hospital, Bari, Italy
| | - Heiner Boeing
- Unit of Research Methodology and Data Sciences for Population Health, "Salus in Apulia Study" National Institute of Gastroenterology "S. de Bellis" Research Hospital, Bari, Italy.,Data Analysis Unit, National Institute of Gastroenterology "S. de Bellis" Research Hospital, Bari, Italy.,German Institute of Human Nutrition Potsdam-Rehbrücke, Nuthetal, Germany
| | - Rodolfo Sardone
- Unit of Research Methodology and Data Sciences for Population Health, "Salus in Apulia Study" National Institute of Gastroenterology "S. de Bellis" Research Hospital, Bari, Italy
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10
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Alvarado JC, Fuentes-Santamaría V, Melgar-Rojas P, Gabaldón-Ull MC, Cabanes-Sanchis JJ, Juiz JM. Oral Antioxidant Vitamins and Magnesium Limit Noise-Induced Hearing Loss by Promoting Sensory Hair Cell Survival: Role of Antioxidant Enzymes and Apoptosis Genes. Antioxidants (Basel) 2020; 9:E1177. [PMID: 33255728 PMCID: PMC7761130 DOI: 10.3390/antiox9121177] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2020] [Revised: 11/16/2020] [Accepted: 11/19/2020] [Indexed: 01/01/2023] Open
Abstract
Noise induces oxidative stress in the cochlea followed by sensory cell death and hearing loss. The proof of principle that injections of antioxidant vitamins and Mg2+ prevent noise-induced hearing loss (NIHL) has been established. However, effectiveness of oral administration remains controversial and otoprotection mechanisms are unclear. Using auditory evoked potentials, quantitative PCR, and immunocytochemistry, we explored effects of oral administration of vitamins A, C, E, and Mg2+ (ACEMg) on auditory function and sensory cell survival following NIHL in rats. Oral ACEMg reduced auditory thresholds shifts after NIHL. Improved auditory function correlated with increased survival of sensory outer hair cells. In parallel, oral ACEMg modulated the expression timeline of antioxidant enzymes in the cochlea after NIHL. There was increased expression of glutathione peroxidase-1 and catalase at 1 and 10 days, respectively. Also, pro-apoptotic caspase-3 and Bax levels were diminished in ACEMg-treated rats, at 10 and 30 days, respectively, following noise overstimulation, whereas, at day 10 after noise exposure, the levels of anti-apoptotic Bcl-2, were significantly increased. Therefore, oral ACEMg improves auditory function by limiting sensory hair cell death in the auditory receptor following NIHL. Regulation of the expression of antioxidant enzymes and apoptosis-related proteins in cochlear structures is involved in such an otoprotective mechanism.
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Affiliation(s)
- Juan C. Alvarado
- Instituto de Investigación en Discapacidades Neurológicas (IDINE), School of Medicine, Universidad de Castilla-La Mancha, 02008 Albacete, Spain; (V.F.-S.); (P.M.-R.); (M.C.G.-U.); (J.J.C.-S.)
| | - Verónica Fuentes-Santamaría
- Instituto de Investigación en Discapacidades Neurológicas (IDINE), School of Medicine, Universidad de Castilla-La Mancha, 02008 Albacete, Spain; (V.F.-S.); (P.M.-R.); (M.C.G.-U.); (J.J.C.-S.)
| | - Pedro Melgar-Rojas
- Instituto de Investigación en Discapacidades Neurológicas (IDINE), School of Medicine, Universidad de Castilla-La Mancha, 02008 Albacete, Spain; (V.F.-S.); (P.M.-R.); (M.C.G.-U.); (J.J.C.-S.)
| | - María C. Gabaldón-Ull
- Instituto de Investigación en Discapacidades Neurológicas (IDINE), School of Medicine, Universidad de Castilla-La Mancha, 02008 Albacete, Spain; (V.F.-S.); (P.M.-R.); (M.C.G.-U.); (J.J.C.-S.)
| | - José J. Cabanes-Sanchis
- Instituto de Investigación en Discapacidades Neurológicas (IDINE), School of Medicine, Universidad de Castilla-La Mancha, 02008 Albacete, Spain; (V.F.-S.); (P.M.-R.); (M.C.G.-U.); (J.J.C.-S.)
| | - José M. Juiz
- Instituto de Investigación en Discapacidades Neurológicas (IDINE), School of Medicine, Universidad de Castilla-La Mancha, 02008 Albacete, Spain; (V.F.-S.); (P.M.-R.); (M.C.G.-U.); (J.J.C.-S.)
- Department of Otolaryngology, Hannover Medical School, NIFE-VIANNA, Cluster of Excellence Hearing4all-German Research Foundation, 30625 Hannover, Germany
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11
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Alvarado JC, Fuentes-Santamaría V, Juiz JM. Antioxidants and Vasodilators for the Treatment of Noise-Induced Hearing Loss: Are They Really Effective? Front Cell Neurosci 2020; 14:226. [PMID: 32792910 PMCID: PMC7387569 DOI: 10.3389/fncel.2020.00226] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2020] [Accepted: 06/29/2020] [Indexed: 12/26/2022] Open
Abstract
We live in a world continuously immersed in noise, an environmental, recreational, and occupational factor present in almost every daily human activity. Exposure to high-level noise could affect the auditory function of individuals at any age, resulting in a condition called noise-induced hearing loss (NIHL). Given that by 2018, more than 400 million people worldwide were suffering from disabling hearing loss and that about one-third involved noise over-exposure, which represents more than 100 million people, this hearing impairment represents a serious health problem. As of today, there are no therapeutic measures available to treat NIHL. Conventional preventive measures, including public awareness and education and physical barriers to noise, do not seem to suffice, as the population is still being affected by damaging noise levels. Therefore, it is necessary to develop or test pharmacological agents that may prevent and/or diminish the impact of noise on hearing. Data availability about the pathophysiological processes involved in triggering NIHL has allowed researchers to use compounds, that could act as effective therapies, by targeting specific mechanisms such as the excess generation of free radicals and blood flow restriction to the cochlea. In this review, we summarize the advantages/disadvantages of these therapeutic agents, providing a critical view of whether they could be effective in the human clinic.
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Affiliation(s)
- Juan Carlos Alvarado
- Facultad de Medicina, Instituto de Investigación en Discapacidades, Neurológicas (IDINE), Universidad de Castilla-La Mancha, Albacete, Spain
| | - Verónica Fuentes-Santamaría
- Facultad de Medicina, Instituto de Investigación en Discapacidades, Neurológicas (IDINE), Universidad de Castilla-La Mancha, Albacete, Spain
| | - José M Juiz
- Facultad de Medicina, Instituto de Investigación en Discapacidades, Neurológicas (IDINE), Universidad de Castilla-La Mancha, Albacete, Spain.,Department of Otolaryngology, Hannover Medical School, NIFE-VIANNA, Cluster of Excellence Hearing4all-German Research Foundation, Hannover, Germany
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12
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Curhan SG, Halpin C, Wang M, Eavey RD, Curhan GC. Prospective Study of Dietary Patterns and Hearing Threshold Elevation. Am J Epidemiol 2020; 189:204-214. [PMID: 31608356 DOI: 10.1093/aje/kwz223] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2019] [Revised: 09/18/2019] [Accepted: 09/20/2019] [Indexed: 01/07/2023] Open
Abstract
We conducted a prospective study of dietary patterns and longitudinal change in audiometric hearing thresholds among 3,135 women (mean age = 59 years) in the Nurses' Health Study II (2012-2018). Diet adherence scores for the Dietary Approaches to Stop Hypertension (DASH) and Alternate Mediterranean (AMED) diets and the Alternate Healthy Eating Index 2010 (AHEI-2010) were calculated using validated food-frequency questionnaires. Baseline and 3-year follow-up hearing sensitivities were assessed by pure-tone audiometry at 19 US sites. We used multivariable-adjusted logistic regression models to examine independent associations between diet adherence scores and risk of ≥5 dB elevation in the pure-tone average (PTA) of low-frequency (LPTA0.5,1,2 kHz), mid-frequency (MPTA3,4 kHz), and high-frequency (HPTA6,8 kHz) hearing thresholds. Higher adherence scores were associated with lower risk of hearing loss. Compared with the lowest quintile of DASH score, the multivariable-adjusted odds ratios for mid-frequency and high-frequency threshold elevation in the highest quintile were 0.71 (95% confidence interval (CI): 0.55, 0.92; P for trend = 0.003) and 0.75 (95% CI: 0.59, 0.96; P for trend = 0.02); for AMED and AHEI scores, for mid-frequency threshold elevation, they were 0.77 (95% CI: 0.60, 0.99; P for trend = 0.02) and 0.72 (95% CI: 0.57, 0.92; P for trend = 0.002). Nonsignificant inverse associations were observed for high-frequency threshold elevation. There were no significant associations between adherence scores and low-frequency threshold elevation. Our findings indicate that eating a healthy diet might reduce the risk of acquired hearing loss.
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Affiliation(s)
- Sharon G Curhan
- Channing Division of Network Medicine, Department of Medicine, Brigham and Women’s Hospital, Boston, Massachusetts
- Harvard Medical School, Boston, Massachusetts
| | | | - Molin Wang
- Channing Division of Network Medicine, Department of Medicine, Brigham and Women’s Hospital, Boston, Massachusetts
- Department of Biostatistics, Harvard T.H. Chan School of Public Health, Boston, Massachusetts
- Department of Epidemiology, Harvard T.H. Chan School of Public Health, Boston, Massachusetts
| | - Roland D Eavey
- Vanderbilt Bill Wilkerson Center for Otolaryngology and Communication Sciences and the Department of Otolaryngology, Vanderbilt University Medical Center, Nashville, Tennessee
| | - Gary C Curhan
- Channing Division of Network Medicine, Department of Medicine, Brigham and Women’s Hospital, Boston, Massachusetts
- Harvard Medical School, Boston, Massachusetts
- Department of Epidemiology, Harvard T.H. Chan School of Public Health, Boston, Massachusetts
- Renal Division, Department of Medicine, Brigham and Women’s Hospital, Boston, Massachusetts
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13
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Prasad KN, Bondy SC. Increased oxidative stress, inflammation, and glutamate: Potential preventive and therapeutic targets for hearing disorders. Mech Ageing Dev 2019; 185:111191. [PMID: 31765645 DOI: 10.1016/j.mad.2019.111191] [Citation(s) in RCA: 40] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2019] [Revised: 09/30/2019] [Accepted: 11/20/2019] [Indexed: 12/17/2022]
Abstract
Hearing disorders constitute one of the major health concerns in the USA. Decades of basic and clinical studies have identified numerous ototoxic agents and investigated their modes of action on the inner ear, utilizing tissue culture as well as animal and human models. Current preventive and therapeutic approaches are considered unsatisfactory. Therefore, additional modalities should be developed. Many studies suggest that increased levels of oxidative stress, chronic inflammation, and glutamate play an important role in the initiation and progression of damage to the inner ear leading to hearing impairments. To prevent these cellular deficits, antioxidants, anti-inflammatory agents, and antagonists of glutamate receptor have been used individually or in combination with limited success. It is essential, therefore, to simultaneously enhance the levels of antioxidant enzymes by activating the Nrf2 (a nuclear transcriptional factor) pathway, dietary and endogenous antioxidant compounds, and B12-vitamins in order to reduce the levels of oxidative stress, chronic inflammation, and glutamate at the same time. This review presents evidence to show that increased levels of these cellular metabolites, biochemical or factors are involved in the pathogenesis of cochlea leading to hearing impairments. It presents scientific rationale for the use of a mixture of micronutrients that may decrease the levels of oxidative damage, chronic inflammation, and glutamate at the same time. The benefits for using oral administration of proposed micronutrient mixture in humans are presented. Animal and limited human studies indirectly suggest that orally administered micronutrients can accumulate in the inner ear. Therefore, this route of administration may be useful in prevention, and in combination with standard care, in improved management of hearing problems following exposure to well-recognized and studied ototoxic agents, such as noise, cisplatin, aminoglycoside antibiotics, and advanced age.
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Affiliation(s)
- Kadar N Prasad
- Engage Global, 245 El Faisan Drive, San Rafael, CA, 94903, United States.
| | - Stephen C Bondy
- Center for Occupational and Environmental Health, Department of Medicine, University of California, Irvine, CA, 92697-1830, United States
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14
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Spankovich C, Le Prell CG. The role of diet in vulnerability to noise-induced cochlear injury and hearing loss. THE JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA 2019; 146:4033. [PMID: 31795697 DOI: 10.1121/1.5132707] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
The influence of dietary nutrient intake on the onset and trajectory of hearing loss during aging and in mediating protection from challenges such as noise is an important relationship yet to be fully appreciated. Dietary intake provides essential nutrients that support basic cellular processes related to influencing cellular stress response, immune response, cardiometabolic status, neural status, and psychological well-being. Dietary quality has been shown to alter risk for essentially all chronic health conditions including hearing loss and tinnitus. Evidence of nutrients with antioxidant, anti-inflammatory, and anti-ischemic properties, and overall healthy diet quality as otoprotective strategies are slowly accumulating, but many questions remain unanswered. In this article, the authors will discuss (1) animal models in nutritional research, (2) evidence of dietary nutrient-based otoprotection, and (3) consideration of confounds and limitations to nutrient and dietary study in hearing sciences. Given that there are some 60 physiologically essential nutrients, unraveling the intricate biochemistry and multitude of interactions among nutrients may ultimately prove infeasible; however, the wealth of available data suggesting healthy nutrient intake to be associated with improved hearing outcomes suggests the development of evidence-based guidance regarding diets that support healthy hearing may not require precise understanding of all possible interactions among variables. Clinical trials evaluating otoprotective benefits of nutrients should account for dietary quality, noise exposure history, and exercise habits as potential covariates that may influence the efficacy and effectiveness of test agents; pharmacokinetic measures are also encouraged.
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Affiliation(s)
- Christopher Spankovich
- Department of Otolaryngology and Communicative Sciences, University of Mississippi Medical Center, Jackson, Mississippi 39216, USA
| | - Colleen G Le Prell
- School of Behavioral and Brain Sciences, University of Texas at Dallas, Dallas, Texas 75080, USA
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15
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Alvarado JC, Fuentes-Santamaría V, Gabaldón-Ull MC, Juiz JM. Age-Related Hearing Loss Is Accelerated by Repeated Short-Duration Loud Sound Stimulation. Front Neurosci 2019; 13:77. [PMID: 30872984 PMCID: PMC6402475 DOI: 10.3389/fnins.2019.00077] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2018] [Accepted: 01/24/2019] [Indexed: 12/18/2022] Open
Abstract
Both age-related hearing loss (ARHL) and noise-induced hearing loss (NIHL) may share pathophysiological mechanisms in that they are associated with excess free radical formation and cochlear blood flow reduction, leading to cochlear damage. Therefore, it is possible that short, but repeated exposures to relatively loud noise during extended time periods, like in leisure (i.e., musical devices and concerts) or occupational noise exposures, may add to cochlear aging mechanisms, having an impact on the onset and/or progression of ARHL. Consequently, the aim of the present study was to determine if repeated short-duration overexposure to a long-term noise could accelerate permanent auditory threshold shifts associated with auditory aging in an animal model of ARHL. Toward this goal, young adult, 3-month-old Wistar rats were divided into two groups: one exposed (E) and the other non-exposed (NE) to noise overstimulation. The stimulation protocol consisted of 1 h continuous white noise at 110 dB sound pressure level (SPL), 5 days a week, allowing 2 days for threshold recovery before initiating another stimulation round, until the animals reached an age of 18 months. Auditory brainstem response (ABR) recordings at 0.5, 1, 2, 4, 8, 16, and 32 kHz were performed at 3, 6, 12, and 18 months of age. The results demonstrate that in the E group there were significant increases in auditory thresholds at all tested frequencies starting already at 6 months of age, which extended at 12 and 18 months. However, in NE animals threshold shifts were not evident until 12 months, extending to 18 months of age. Threshold shifts observed in the E animals at 6 and 12 months were significantly larger than those observed in the NE group at the same ages. Threshold shifts at 6 and 12 months in E animals resembled those at 12 and 18 months in NE animals, respectively. This suggests that repeated noise overstimulation in short-duration episodes accelerates the time-course of hearing loss in this animal model of ARHL.
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Affiliation(s)
- Juan Carlos Alvarado
- Instituto de Investigación en Discapacidades Neurológicas (IDINE), Albacete, Spain Facultad de Medicina, Universidad de Castilla-La Mancha, Albacete, Spain
| | - Verónica Fuentes-Santamaría
- Instituto de Investigación en Discapacidades Neurológicas (IDINE), Albacete, Spain Facultad de Medicina, Universidad de Castilla-La Mancha, Albacete, Spain
| | - María Cruz Gabaldón-Ull
- Instituto de Investigación en Discapacidades Neurológicas (IDINE), Albacete, Spain Facultad de Medicina, Universidad de Castilla-La Mancha, Albacete, Spain
| | - José M Juiz
- Instituto de Investigación en Discapacidades Neurológicas (IDINE), Albacete, Spain Facultad de Medicina, Universidad de Castilla-La Mancha, Albacete, Spain
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