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Ohlemiller KK, Dwyer N, Henson V, Fasman K, Hirose K. A critical evaluation of "leakage" at the cochlear blood-stria-barrier and its functional significance. Front Mol Neurosci 2024; 17:1368058. [PMID: 38486963 PMCID: PMC10937559 DOI: 10.3389/fnmol.2024.1368058] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2024] [Accepted: 02/16/2024] [Indexed: 03/17/2024] Open
Abstract
The blood-labyrinth-barrier (BLB) is a semipermeable boundary between the vasculature and three separate fluid spaces of the inner ear, the perilymph, the endolymph and the intrastrial space. An important component of the BLB is the blood-stria-barrier, which shepherds the passage of ions and metabolites from strial capillaries into the intrastrial space. Some investigators have reported increased "leakage" from these capillaries following certain experimental interventions, or in the presence of inflammation or genetic variants. This leakage is generally thought to be harmful to cochlear function, principally by lowering the endocochlear potential (EP). Here, we examine evidence for this dogma. We find that strial capillaries are not exclusive, and that the asserted detrimental influence of strial capillary leakage is often confounded by hair cell damage or intrinsic dysfunction of the stria. The vast majority of previous reports speculate about the influence of strial vascular barrier function on the EP without directly measuring the EP. We argue that strial capillary leakage is common across conditions and species, and does not significantly impact the EP or hearing thresholds, either on evidentiary or theoretical grounds. Instead, strial capillary endothelial cells and pericytes are dynamic and allow permeability of varying degrees in response to specific conditions. We present observations from mice and demonstrate that the mechanisms of strial capillary transport are heterogeneous and inconsistent among inbred strains.
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Affiliation(s)
- Kevin K. Ohlemiller
- Department of Otolaryngology, Washington University School of Medicine, St. Louis, MO, United States
- Program in Communication Sciences and Audiology, Washington University School of Medicine, St. Louis, MO, United States
| | - Noël Dwyer
- Program in Communication Sciences and Audiology, Washington University School of Medicine, St. Louis, MO, United States
| | - Veronica Henson
- Program in Communication Sciences and Audiology, Washington University School of Medicine, St. Louis, MO, United States
| | - Kaela Fasman
- Program in Communication Sciences and Audiology, Washington University School of Medicine, St. Louis, MO, United States
| | - Keiko Hirose
- Department of Otolaryngology, Washington University School of Medicine, St. Louis, MO, United States
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2
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Barnes CC, Yee KT, Vetter DE. Conditional Ablation of Glucocorticoid and Mineralocorticoid Receptors from Cochlear Supporting Cells Reveals Their Differential Roles for Hearing Sensitivity and Dynamics of Recovery from Noise-Induced Hearing Loss. Int J Mol Sci 2023; 24:3320. [PMID: 36834731 PMCID: PMC9961551 DOI: 10.3390/ijms24043320] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2022] [Revised: 02/01/2023] [Accepted: 02/03/2023] [Indexed: 02/11/2023] Open
Abstract
Endogenous glucocorticoids (GC) are known to modulate basic elements of cochlear physiology. These include both noise-induced injury and circadian rhythms. While GC signaling in the cochlea can directly influence auditory transduction via actions on hair cells and spiral ganglion neurons, evidence also indicates that GC signaling exerts effects via tissue homeostatic processes that can include effects on cochlear immunomodulation. GCs act at both the glucocorticoid receptor (GR) and the mineralocorticoid receptor (MR). Most cell types in the cochlea express both receptors sensitive to GCs. The GR is associated with acquired sensorineural hearing loss (SNHL) through its effects on both gene expression and immunomodulatory programs. The MR has been associated with age-related hearing loss through dysfunction of ionic homeostatic balance. Cochlear supporting cells maintain local homeostatic requirements, are sensitive to perturbation, and participate in inflammatory signaling. Here, we have used conditional gene manipulation techniques to target Nr3c1 (GR) or Nr3c2 (MR) for tamoxifen-induced gene ablation in Sox9-expressing cochlear supporting cells of adult mice to investigate whether either of the receptors sensitive to GCs plays a role in protecting against (or exacerbating) noise-induced cochlear damage. We have selected mild intensity noise exposure to examine the role of these receptors related to more commonly experienced noise levels. Our results reveal distinct roles of these GC receptors for both basal auditory thresholds prior to noise exposure and during recovery from mild noise exposure. Prior to noise exposure, auditory brainstem responses (ABRs) were measured in mice carrying the floxed allele of interest and the Cre recombinase transgene, but not receiving tamoxifen injections (defined as control (no tamoxifen treatment), versus conditional knockout (cKO) mice, defined as mice having received tamoxifen injections. Results revealed hypersensitive thresholds to mid- to low-frequencies after tamoxifen-induced GR ablation from Sox9-expressing cochlear supporting cells compared to control (no tamoxifen) mice. GR ablation from Sox9-expressing cochlear supporting cells resulted in a permanent threshold shift in mid-basal cochlear frequency regions after mild noise exposure that produced only a temporary threshold shift in both control (no tamoxifen) f/fGR:Sox9iCre+ and heterozygous f/+GR:Sox9iCre+ tamoxifen-treated mice. A similar comparison of basal ABRs measured in control (no tamoxifen) and tamoxifen-treated, floxed MR mice prior to noise exposure indicated no difference in baseline thresholds. After mild noise exposure, MR ablation was initially associated with a complete threshold recovery at 22.6 kHz by 3 days post-noise. Threshold continued to shift to higher sensitivity over time such that by 30 days post-noise exposure the 22.6 kHz ABR threshold was 10 dB more sensitive than baseline. Further, MR ablation produced a temporary reduction in peak 1 neural amplitude one day post-noise. While supporting cell GR ablation trended towards reducing numbers of ribbon synapses, MR ablation reduced ribbon synapse counts but did not exacerbate noise-induced damage including synapse loss at the experimental endpoint. GR ablation from the targeted supporting cells increased the basal resting number of Iba1-positive (innate) immune cells (no noise exposure) and decreased the number of Iba1-positive cells seven days following noise exposure. MR ablation did not alter innate immune cell numbers at seven days post-noise exposure. Taken together, these findings support differential roles of cochlear supporting cell MR and GR expression at basal, resting conditions and especially during recovery from noise exposure.
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Affiliation(s)
- Charles C. Barnes
- Graduate Program in Neuroscience, University of Mississippi Medical Center, Jackson, MS 39216, USA
| | - Kathleen T. Yee
- Department of Otolaryngology–Head and Neck Surgery, University of Mississippi Medical Center, Jackson, MS 39216, USA
| | - Douglas E. Vetter
- Graduate Program in Neuroscience, University of Mississippi Medical Center, Jackson, MS 39216, USA
- Department of Otolaryngology–Head and Neck Surgery, University of Mississippi Medical Center, Jackson, MS 39216, USA
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Anfuso CD, Cosentino A, Agafonova A, Zappalà A, Giurdanella G, Trovato Salinaro A, Calabrese V, Lupo G. Pericytes of Stria Vascularis Are Targets of Cisplatin-Induced Ototoxicity: New Insights into the Molecular Mechanisms Involved in Blood-Labyrinth Barrier Breakdown. Int J Mol Sci 2022; 23:ijms232415790. [PMID: 36555432 PMCID: PMC9781621 DOI: 10.3390/ijms232415790] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2022] [Revised: 12/10/2022] [Accepted: 12/11/2022] [Indexed: 12/15/2022] Open
Abstract
The stria vascularis (SV) contributes to cochlear homeostasis and consists of three layers, one of which contains the blood-labyrinthic barrier (BLB), with a large number of bovine cochlear pericytes (BCPs). Cisplatin is a chemotherapeutic drug that can damage the SV and cause hearing loss. In this study, cell viability, proliferation rate, cytotoxicity and reactive oxygen species production were evaluated. The protein content of phospho-extracellular signal-regulated kinases (ERK) 1/2, total ERK 1/2, phospho-cytosolic phospholipase A2 (cPLA2), total cPLA2 and cyclooxygenase 2 (COX-2) and the release of prostaglandin E2 (PGE2) and vascular endothelial growth factor (VEGF) from BCPs were analyzed. Finally, the protective effect of platelet-derived growth factor (PDGF-BB) on BCPs treated with cisplatin was investigated. Cisplatin reduced viability and proliferation, activated ERK 1/2, cPLA2 and COX-2 expression and increased PGE2 and VEGF release; these effects were reversed by Dexamethasone. The presence of PDGF-BB during the treatment with cisplatin significantly increased the proliferation rate. No studies on cell regeneration in ear tissue evaluated the effect of the PDGF/Dex combination. The aim of this study was to investigate the effects of cisplatin on cochlear pericytes and propose new otoprotective agents aimed at preventing the reduction of their vitality and thus maintaining the BLB structure.
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Affiliation(s)
- Carmelina Daniela Anfuso
- Section of Medical Biochemistry, Department of Biomedical and Biotechnological Sciences, School of Medicine, University of Catania, 95123 Catania, Italy
| | - Alessia Cosentino
- Section of Medical Biochemistry, Department of Biomedical and Biotechnological Sciences, School of Medicine, University of Catania, 95123 Catania, Italy
| | - Aleksandra Agafonova
- Section of Medical Biochemistry, Department of Biomedical and Biotechnological Sciences, School of Medicine, University of Catania, 95123 Catania, Italy
| | - Agata Zappalà
- Section of Physiology, Department of Biomedical and Biotechnological Sciences, School of Medicine, University of Catania, 95123 Catania, Italy
| | | | - Angela Trovato Salinaro
- Section of Medical Biochemistry, Department of Biomedical and Biotechnological Sciences, School of Medicine, University of Catania, 95123 Catania, Italy
| | - Vittorio Calabrese
- Section of Medical Biochemistry, Department of Biomedical and Biotechnological Sciences, School of Medicine, University of Catania, 95123 Catania, Italy
| | - Gabriella Lupo
- Section of Medical Biochemistry, Department of Biomedical and Biotechnological Sciences, School of Medicine, University of Catania, 95123 Catania, Italy
- Correspondence:
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Requena T, Keder A, zur Lage P, Albert JT, Jarman AP. A Drosophila model for Meniere's disease: Dystrobrevin is required for support cell function in hearing and proprioception. Front Cell Dev Biol 2022; 10:1015651. [PMID: 36438562 PMCID: PMC9688402 DOI: 10.3389/fcell.2022.1015651] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2022] [Accepted: 10/27/2022] [Indexed: 08/04/2023] Open
Abstract
Meniere's disease (MD) is an inner ear disorder characterised by recurrent vertigo attacks associated with sensorineural hearing loss and tinnitus. Evidence from epidemiology and Whole Exome Sequencing (WES) suggests a genetic susceptibility involving multiple genes, including α-Dystrobrevin (DTNA). Here we investigate a Drosophila model. We show that mutation, or knockdown, of the DTNA orthologue in Drosophila, Dystrobrevin (Dyb), results in defective proprioception and impaired function of Johnston's Organ (JO), the fly's equivalent of the inner ear. Dyb and another component of the dystrophin-glycoprotein complex (DGC), Dystrophin (Dys), are expressed in support cells within JO. Their specific locations suggest that they form part of support cell contacts, thereby helping to maintain the integrity of the hemolymph-neuron diffusion barrier, which is equivalent to a blood-brain barrier. These results have important implications for the human condition, and notably, we note that DTNA is expressed in equivalent cells of the mammalian inner ear.
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Affiliation(s)
- T. Requena
- Biomedical Sciences: Centre for Discovery Brain Sciences, Edinburgh Medical School, University of Edinburgh, Edinburgh, United Kingdom
- Division of Functional Genetics and Development, The Royal Dick School of Veterinary Sciences, The Roslin Institute, The University of Edinburgh, Edinburgh, United Kingdom
| | - A. Keder
- Ear Institute, University College London, London, United Kingdom
| | - P. zur Lage
- Biomedical Sciences: Centre for Discovery Brain Sciences, Edinburgh Medical School, University of Edinburgh, Edinburgh, United Kingdom
| | - J. T. Albert
- Ear Institute, University College London, London, United Kingdom
| | - A. P. Jarman
- Biomedical Sciences: Centre for Discovery Brain Sciences, Edinburgh Medical School, University of Edinburgh, Edinburgh, United Kingdom
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5
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Zhang J, Fan W, Neng L, Chen B, Wang Y, Zuo B, Lu W. Adenosine improves LPS-induced ROS expression and increasing in monolayer permeability of endothelial cell via acting on A2AR. Microvasc Res 2022; 143:104403. [PMID: 35753505 DOI: 10.1016/j.mvr.2022.104403] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2021] [Revised: 05/23/2022] [Accepted: 06/20/2022] [Indexed: 11/19/2022]
Abstract
Blood-labyrinth barrier (BLB) disruption plays a crucial role in the development of otitis media. The aims of our study was to explore the role and action mechanism of adenosine in LPS-induced endothelial cells (ECs) damage, which are one of the major principal cell type for blood-labyrinth barrier (BLB), and so as to assess the potential of adenosine to be used in the treatment of BLB disruption in animal experiment. In our study, ECs were treated with LPS to mimic BLB damage in vitro. Our data showed that adenosine at dosage of 1, 10, and 20 μM had no influence on the cell viability of ECs. LPS treatment obviously suppressed the expression of Occludin and Zonula occludens-1 (ZO-1) in ECs, which was partly recused by adenosine treatment. Meantime, LPS-induced increasing in reactive oxygen species (ROS) production and ECs permeability also was rescued by adenosine treatment. However, inhibition the A2A receptor (A2AR) could attenuate the influence of adenosine on LPS-treated ECs, indicating that adenosine alleviated LPS-induced BLB damage by activating A2AR. Moreover, the inhibition of adenosine to LPS-induced inactivation of AMPK/AKT signaling pathway was partly recused by A2AR suppression. In addition, Compound C (an AMPK inhibitor) decreased the expression of Occludin and ZO-1 in ECs following LPS combined with adenosine treatment. In conclusion, adenosine alleviates LPS-induced BLB damage via AMPK/AKT pathway through activation of A2AR. This work suggests that adenosine may be a candidate drug for the treatment of BLB dysfunction-related diseases.
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Affiliation(s)
- Jinhui Zhang
- Department of otorhinolaryngology, Head and Neck surgery, The First Affiliated Hospital of Zhengzhou University, No 1 Jianshe Road, Zhengzhou 450052, Henan, China.
| | - Wenya Fan
- Department of otorhinolaryngology, Head and Neck surgery, The First Affiliated Hospital of Zhengzhou University, No 1 Jianshe Road, Zhengzhou 450052, Henan, China
| | - Lingling Neng
- Department of otorhinolaryngology, Head and Neck surgery, The First Affiliated Hospital of Zhengzhou University, No 1 Jianshe Road, Zhengzhou 450052, Henan, China
| | - Bei Chen
- Department of otorhinolaryngology, Head and Neck surgery, The First Affiliated Hospital of Zhengzhou University, No 1 Jianshe Road, Zhengzhou 450052, Henan, China
| | - Yanting Wang
- Department of Anesthesiology, The Affiliated Hospital of Qingdao University, No 16, Jiangsu Road, Qingdao, Shandong, China
| | - Bin Zuo
- Department of otorhinolaryngology, Head and Neck surgery, The First Affiliated Hospital of Zhengzhou University, No 1 Jianshe Road, Zhengzhou 450052, Henan, China
| | - Wei Lu
- Department of otorhinolaryngology, Head and Neck surgery, The First Affiliated Hospital of Zhengzhou University, No 1 Jianshe Road, Zhengzhou 450052, Henan, China.
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6
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Garvin J, Semenikhina M, Liu Q, Rarick K, Isaeva E, Levchenko V, Staruschenko A, Palygin O, Harder D, Cohen S. Astrocytic responses to high glucose impair barrier formation in cerebral microvessel endothelial cells. Am J Physiol Regul Integr Comp Physiol 2022; 322:R571-R580. [PMID: 35412389 PMCID: PMC9109795 DOI: 10.1152/ajpregu.00315.2020] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2020] [Revised: 03/06/2022] [Accepted: 03/08/2022] [Indexed: 12/27/2022]
Abstract
Hyperglycemic conditions are prodromal to blood-brain barrier (BBB) impairment. The BBB comprises cerebral microvessel endothelial cells (CMECs) that are surrounded by astrocytic foot processes. Astrocytes express high levels of gap junction connexin 43 (Cx43), which play an important role in autocrine and paracrine signaling interactions that mediate gliovascular cross talk through secreted products. One of the key factors of the astrocytic "secretome" is vascular endothelial growth factor (VEGF), a potent angiogenic factor that can disrupt BBB integrity. We hypothesize that high-glucose conditions change the astrocytic expression of Cx43 and increase VEGF secretion leading to impairment of CMEC barrier properties in vitro and in vivo. Using coculture of neonatal rat astrocytes and CMEC, we mimic hyperglycemic conditions using high-glucose (HG) feeding media and show a significant decrease in Cx43 expression and the corresponding increase in secreted VEGF. This result was confirmed by the analyses of Cx43 and VEGF protein levels in the brain cortex samples from the type 2 diabetic rat (T2DN). To further characterize inducible changes in BBB, we measured transendothelial cell electrical resistance (TEER) and tight junction protein levels in cocultured conditioned astrocytes with isolated rat CMEC. The coculture monolayer's integrity and permeability were significantly compromised by HG media exposure, which was indicated by decreased TEER without a change in tight junction protein levels in CMEC. Our study provides insight into gliovascular adaptations to increased glucose levels resulting in impaired cellular cross talk between astrocytes and CMEC, which could be one explanation for cerebral BBB disruption in diabetic conditions.
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Affiliation(s)
- Jodi Garvin
- Department of Pediatrics, Medical College of Wisconsin, Milwaukee, Wisconsin
| | - Marharyta Semenikhina
- Department of Physiology, Medical College of Wisconsin, Milwaukee, Wisconsin
- Division of Nephrology, Department of Medicine, Medical University of South Carolina, Charleston, South Carolina
| | - Qiuli Liu
- Department of Pediatrics, Medical College of Wisconsin, Milwaukee, Wisconsin
| | - Kevin Rarick
- Department of Pediatrics, Medical College of Wisconsin, Milwaukee, Wisconsin
| | - Elena Isaeva
- Department of Physiology, Medical College of Wisconsin, Milwaukee, Wisconsin
| | - Vladislav Levchenko
- Department of Physiology, Medical College of Wisconsin, Milwaukee, Wisconsin
- Department of Molecular Pharmacology and Physiology, University of South Florida, Tampa, Florida
| | - Alexander Staruschenko
- Department of Physiology, Medical College of Wisconsin, Milwaukee, Wisconsin
- Department of Molecular Pharmacology and Physiology, University of South Florida, Tampa, Florida
| | - Oleg Palygin
- Department of Physiology, Medical College of Wisconsin, Milwaukee, Wisconsin
- Division of Nephrology, Department of Medicine, Medical University of South Carolina, Charleston, South Carolina
- Department of Regenerative Medicine and Cell Biology, Medical University of South Carolina, Charleston, South Carolina
| | - David Harder
- Department of Physiology, Medical College of Wisconsin, Milwaukee, Wisconsin
| | - Susan Cohen
- Department of Pediatrics, Medical College of Wisconsin, Milwaukee, Wisconsin
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Abstract
Sensorineural hearing loss (SNHL) is a common clinical side effect resulted from the overusing of aminoglycoside antibacterial drugs, such as gentamicin. Oxidative stress is recently evidenced to be an important inducer for SNHL, which is reported to be associated with the knockdown of connexin-43. MiR-106a is recently found as a regulator of connexin-43. The present study aims to investigate whether miR-106a is a vital mediator in the development of SNHL. Firstly, upregulated miR-106a was observed in the peripheral blood sample of SNHL patients. Glucose oxidase (GO) was utilized to induce oxidative injury in isolated rat cochlear marginal cells (MCs), followed by introducing the miR-106a inhibitor. We found that the declined proliferation ability, increased apoptosis, and activated oxidative stress in GO-stimulated MCs were dramatically abolished by the miR-106a inhibitor, accompanied by the upregulation of connexin-43. The targeting correlation between miR-106a and connexin-43 was predicted and confirmed by the dual luciferase gene reporter assay. Furthermore, the regulatory effect of miR-106a inhibitor against the proliferation, apoptosis, and oxidative stress in GO-treated MCs were dramatically abolished by the knockdown of connexin-43. Gentamicin was utilized to establish the SNHL model in rats, followed by the treatments of antagomir-106a and antagomir-106a combined with carbenoxolone, an inhibitor of connexin-43. The alleviated pathological state, reduced apoptosis, and ameliorated oxidative stress in cochlea tissues were observed in antagomir-106a treated SNHL rats, which were dramatically reversed by the co-administration of carbenoxolone. Collectively, miR-106a facilitated the SNHL induced by oxidative stress via targeting connexin-43.
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Affiliation(s)
- Lei Ding
- ENT Department, Beijing University of Chinese Medicine Subsidiary Dongfang Hospital, Beijing, China
| | - Jiaxi Wang
- ENT Department, Beijing University of Chinese Medicine Subsidiary Dongfang Hospital, Beijing, China
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Gentile G, Paciello F, Zorzi V, Spampinato AG, Guarnaccia M, Crispino G, Tettey-Matey A, Scavizzi F, Raspa M, Fetoni AR, Cavallaro S, Mammano F. miRNA and mRNA Profiling Links Connexin Deficiency to Deafness via Early Oxidative Damage in the Mouse Stria Vascularis. Front Cell Dev Biol 2021; 8:616878. [PMID: 33569381 PMCID: PMC7868390 DOI: 10.3389/fcell.2020.616878] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2020] [Accepted: 12/10/2020] [Indexed: 12/15/2022] Open
Abstract
Pathogenic mutations in the non-syndromic hearing loss and deafness 1 (DFNB1) locus are the primary cause of monogenic inheritance for prelingual hearing loss. To unravel molecular pathways involved in etiopathology and look for early degeneration biomarkers, we used a system biology approach to analyze Cx30−/− mice at an early cochlear post-natal developmental stage. These mice are a DFNB1 mouse model with severely reduced expression levels of two connexins in the inner ear, Cx30, and Cx26. Integrated analysis of miRNA and mRNA expression profiles in the cochleae of Cx30−/− mice at post-natal day 5 revealed the overexpression of five miRNAs (miR-34c, miR-29b, miR-29c, miR-141, and miR-181a) linked to apoptosis, oxidative stress, and cochlear degeneration, which have Sirt1 as a common target of transcriptional and/or post-transcriptional regulation. In young adult Cx30−/− mice (3 months of age), these alterations culminated with blood barrier disruption in the Stria vascularis (SV), which is known to have the highest aerobic metabolic rate of all cochlear structures and whose microvascular alterations contribute to age-related degeneration and progressive decline of auditory function. Our experimental validation of selected targets links hearing acquisition failure in Cx30−/− mice, early oxidative stress, and metabolic dysregulation to the activation of the Sirt1–p53 axis. This is the first integrated analysis of miRNA and mRNA in the cochlea of the Cx30−/− mouse model, providing evidence that connexin downregulation determines a miRNA-mediated response which leads to chronic exhaustion of cochlear antioxidant defense mechanisms and consequent SV dysfunction. Our analyses support the notion that connexin dysfunction intervenes early on during development, causing vascular damage later on in life. This study identifies also early miRNA-mediated biomarkers of hearing impairment, either inherited or age related.
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Affiliation(s)
- Giulia Gentile
- Department of Biomedical Sciences, National Research Council (CNR) Institute for Biomedical Research and Innovation, Catania, Italy
| | - Fabiola Paciello
- Department of Neuroscience, Università Cattolica del Sacro Cuore, Rome, Italy.,Fondazione Policlinico Universitario A. Gemelli Istituto di Ricovero e Cura a Carattere Scientifico (IRCCS), Rome, Italy
| | - Veronica Zorzi
- Department of Head and Neck Surgery, Università Cattolica del Sacro Cuore, Rome, Italy.,Department of Biomedical Sciences, National Research Council (CNR) Institute of Biochemistry and Cell Biology, Rome, Italy
| | - Antonio Gianmaria Spampinato
- Department of Biomedical Sciences, National Research Council (CNR) Institute for Biomedical Research and Innovation, Catania, Italy.,Department of Mathematics and Computer Science, University of Catania, Catania, Italy
| | - Maria Guarnaccia
- Department of Biomedical Sciences, National Research Council (CNR) Institute for Biomedical Research and Innovation, Catania, Italy
| | - Giulia Crispino
- Department of Biomedical Sciences, National Research Council (CNR) Institute of Biochemistry and Cell Biology, Rome, Italy
| | - Abraham Tettey-Matey
- Department of Biomedical Sciences, National Research Council (CNR) Institute of Biochemistry and Cell Biology, Rome, Italy
| | - Ferdinando Scavizzi
- Department of Biomedical Sciences, National Research Council (CNR) Institute of Biochemistry and Cell Biology, Rome, Italy
| | - Marcello Raspa
- Fondazione Policlinico Universitario A. Gemelli Istituto di Ricovero e Cura a Carattere Scientifico (IRCCS), Rome, Italy
| | - Anna Rita Fetoni
- Fondazione Policlinico Universitario A. Gemelli Istituto di Ricovero e Cura a Carattere Scientifico (IRCCS), Rome, Italy.,Department of Head and Neck Surgery, Università Cattolica del Sacro Cuore, Rome, Italy
| | - Sebastiano Cavallaro
- Department of Biomedical Sciences, National Research Council (CNR) Institute for Biomedical Research and Innovation, Catania, Italy
| | - Fabio Mammano
- Department of Biomedical Sciences, National Research Council (CNR) Institute of Biochemistry and Cell Biology, Rome, Italy.,Department of Physics and Astronomy "G. Galilei", University of Padua, Padua, Italy
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