The Relevance of Autophagy within Inner Ear in Baseline Conditions and Tinnitus-Related Syndromes
Tinnitus is the perception of noise in the absence of acoustic stimulation (phantom noise). In most patients suffering from chronic peripheral tinnitus, an alteration of outer hair cells (OHC) starting from the stereocilia (SC) occurs. This is common following ototoxic drugs, sound-induced ototoxici...
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MDPI AG
2023-11-01
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| Series: | International Journal of Molecular Sciences |
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| Online Access: | https://www.mdpi.com/1422-0067/24/23/16664 |
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| author | Gloria Lazzeri Francesca Biagioni Michela Ferrucci Stefano Puglisi-Allegra Paola Lenzi Carla Letizia Busceti Francesco Giannessi Francesco Fornai |
| author_facet | Gloria Lazzeri Francesca Biagioni Michela Ferrucci Stefano Puglisi-Allegra Paola Lenzi Carla Letizia Busceti Francesco Giannessi Francesco Fornai |
| author_sort | Gloria Lazzeri |
| collection | DOAJ |
| description | Tinnitus is the perception of noise in the absence of acoustic stimulation (phantom noise). In most patients suffering from chronic peripheral tinnitus, an alteration of outer hair cells (OHC) starting from the stereocilia (SC) occurs. This is common following ototoxic drugs, sound-induced ototoxicity, and acoustic degeneration. In all these conditions, altered coupling between the tectorial membrane (TM) and OHC SC is described. The present review analyzes the complex interactions involving OHC and TM. These need to be clarified to understand which mechanisms may underlie the onset of tinnitus and why the neuropathology of chronic degenerative tinnitus is similar, independent of early triggers. In fact, the fine neuropathology of tinnitus features altered mechanisms of mechanic-electrical transduction (MET) at the level of OHC SC. The appropriate coupling between OHC SC and TM strongly depends on autophagy. The involvement of autophagy may encompass degenerative and genetic tinnitus, as well as ototoxic drugs and acoustic trauma. Defective autophagy explains mitochondrial alterations and altered protein handling within OHC and TM. This is relevant for developing novel treatments that stimulate autophagy without carrying the burden of severe side effects. Specific phytochemicals, such as curcumin and berberin, acting as autophagy activators, may mitigate the neuropathology of tinnitus. |
| first_indexed | 2024-03-09T01:50:28Z |
| format | Article |
| id | doaj.art-04fc27f23a79413ebe7b16c59346883c |
| institution | Directory Open Access Journal |
| issn | 1661-6596 1422-0067 |
| language | English |
| last_indexed | 2024-03-09T01:50:28Z |
| publishDate | 2023-11-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | International Journal of Molecular Sciences |
| spelling | doaj.art-04fc27f23a79413ebe7b16c59346883c2023-12-08T15:16:43ZengMDPI AGInternational Journal of Molecular Sciences1661-65961422-00672023-11-0124231666410.3390/ijms242316664The Relevance of Autophagy within Inner Ear in Baseline Conditions and Tinnitus-Related SyndromesGloria Lazzeri0Francesca Biagioni1Michela Ferrucci2Stefano Puglisi-Allegra3Paola Lenzi4Carla Letizia Busceti5Francesco Giannessi6Francesco Fornai7Human Anatomy, Department of Translational Research and New Technologies in Medicine and Surgery, University of Pisa, 56126 Pisa, PI, ItalyIRCCS, Istituto di Ricovero e Cura a Carattere Scientifico, Neuromed, 86077 Pozzilli, IS, ItalyHuman Anatomy, Department of Translational Research and New Technologies in Medicine and Surgery, University of Pisa, 56126 Pisa, PI, ItalyIRCCS, Istituto di Ricovero e Cura a Carattere Scientifico, Neuromed, 86077 Pozzilli, IS, ItalyHuman Anatomy, Department of Translational Research and New Technologies in Medicine and Surgery, University of Pisa, 56126 Pisa, PI, ItalyIRCCS, Istituto di Ricovero e Cura a Carattere Scientifico, Neuromed, 86077 Pozzilli, IS, ItalyHuman Anatomy, Department of Translational Research and New Technologies in Medicine and Surgery, University of Pisa, 56126 Pisa, PI, ItalyHuman Anatomy, Department of Translational Research and New Technologies in Medicine and Surgery, University of Pisa, 56126 Pisa, PI, ItalyTinnitus is the perception of noise in the absence of acoustic stimulation (phantom noise). In most patients suffering from chronic peripheral tinnitus, an alteration of outer hair cells (OHC) starting from the stereocilia (SC) occurs. This is common following ototoxic drugs, sound-induced ototoxicity, and acoustic degeneration. In all these conditions, altered coupling between the tectorial membrane (TM) and OHC SC is described. The present review analyzes the complex interactions involving OHC and TM. These need to be clarified to understand which mechanisms may underlie the onset of tinnitus and why the neuropathology of chronic degenerative tinnitus is similar, independent of early triggers. In fact, the fine neuropathology of tinnitus features altered mechanisms of mechanic-electrical transduction (MET) at the level of OHC SC. The appropriate coupling between OHC SC and TM strongly depends on autophagy. The involvement of autophagy may encompass degenerative and genetic tinnitus, as well as ototoxic drugs and acoustic trauma. Defective autophagy explains mitochondrial alterations and altered protein handling within OHC and TM. This is relevant for developing novel treatments that stimulate autophagy without carrying the burden of severe side effects. Specific phytochemicals, such as curcumin and berberin, acting as autophagy activators, may mitigate the neuropathology of tinnitus.https://www.mdpi.com/1422-0067/24/23/16664stereociliaouther hair cellsinner hair cellstectorial membraneHensen’s cellsreticular lamina |
| spellingShingle | Gloria Lazzeri Francesca Biagioni Michela Ferrucci Stefano Puglisi-Allegra Paola Lenzi Carla Letizia Busceti Francesco Giannessi Francesco Fornai The Relevance of Autophagy within Inner Ear in Baseline Conditions and Tinnitus-Related Syndromes International Journal of Molecular Sciences stereocilia outher hair cells inner hair cells tectorial membrane Hensen’s cells reticular lamina |
| title | The Relevance of Autophagy within Inner Ear in Baseline Conditions and Tinnitus-Related Syndromes |
| title_full | The Relevance of Autophagy within Inner Ear in Baseline Conditions and Tinnitus-Related Syndromes |
| title_fullStr | The Relevance of Autophagy within Inner Ear in Baseline Conditions and Tinnitus-Related Syndromes |
| title_full_unstemmed | The Relevance of Autophagy within Inner Ear in Baseline Conditions and Tinnitus-Related Syndromes |
| title_short | The Relevance of Autophagy within Inner Ear in Baseline Conditions and Tinnitus-Related Syndromes |
| title_sort | relevance of autophagy within inner ear in baseline conditions and tinnitus related syndromes |
| topic | stereocilia outher hair cells inner hair cells tectorial membrane Hensen’s cells reticular lamina |
| url | https://www.mdpi.com/1422-0067/24/23/16664 |
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