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Xu X, Xu K, Chen F, Yu D, Wang X. Mfsd2a regulates the blood-labyrinth-barrier formation and function through tight junctions and transcytosis. Hear Res 2024; 450:109048. [PMID: 38852535 DOI: 10.1016/j.heares.2024.109048] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/07/2024] [Revised: 05/15/2024] [Accepted: 05/25/2024] [Indexed: 06/11/2024]
Abstract
The Blood-Labyrinth Barrier (BLB) is pivotal for the maintenance of lymphatic homeostasis within the inner ear, yet the intricacies of its development and function are inadequately understood. The present investigation delves into the contribution of the Mfsd2a molecule, integral to the structural and functional integrity of the Blood-Brain Barrier (BBB), to the ontogeny and sustenance of the BLB. Our empirical findings delineate that the maturation of the BLB in murine models is not realized until approximately two weeks post-birth, with preceding stages characterized by notable permeability. Transcriptomic analysis elucidates a marked augmentation in Mfsd2a expression within the lateral wall of the cochlea in specimens exhibiting an intact BLB. Moreover, both in vitro and in vivo assays substantiate that a diminution in Mfsd2a expression detrimentally impacts BLB permeability and structural integrity, principally via the attenuation of tight junction protein expression and the enhancement of endothelial cell transcytosis. These insights underscore the indispensable role of Mfsd2a in ensuring BLB integrity and propose it as a viable target for therapeutic interventions aimed at the amelioration of hearing loss.
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Affiliation(s)
- Xiaoju Xu
- Biobank of Clinical Research Center, Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200100, China
| | - Ke Xu
- Biobank of Clinical Research Center, Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200100, China
| | - Fengqiu Chen
- Biobank of Clinical Research Center, Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200100, China
| | - Dehong Yu
- Materdicine Lab, School of Life Sciences, Shanghai University, Shanghai 200444, China.
| | - Xueling Wang
- Biobank of Clinical Research Center, Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200100, China; Department of Otolaryngology-Head and Neck Surgery, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China; Shanghai Key Laboratory of Translational Medicine on Ear and Nose Diseases, Shanghai, China.
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2
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Li J, Jin X, Kong X, Hu N, Li X, Wang L, Liu M, Li C, Liu Y, Sun L, Gong R. Correlation of endolymphatic hydrops and perilymphatic enhancement with the clinical features of Ménière's disease. Eur Radiol 2024; 34:6036-6046. [PMID: 38308680 DOI: 10.1007/s00330-024-10620-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2023] [Revised: 01/10/2024] [Accepted: 01/15/2024] [Indexed: 02/05/2024]
Abstract
OBJECTIVES To use three-dimensional real inversion recovery (3D-real IR) MRI to investigate correlations between endolymphatic hydrops (EH) grades or the degree of perilymphatic enhancement (PE) and clinical features of Ménière's disease (MD), as previous findings have been inconsistent. METHODS A total of 273 consecutive patients with definite unilateral MD were retrospectively enrolled from September 2020 to October 2021. All patients underwent 3D-real IR and 3D-T2WI 6 h after intravenous gadolinium injection. MD-related symptom duration and vertigo frequency were recorded. EH grades were evaluated, the signal intensity ratio (SIR) was measured, and correlations between clinical features and EH, PE were assessed respectively. RESULTS The study included 123 males and 150 females, with a mean age of 53.0 years. A longer duration of vertigo was associated with higher cochlear EH grades, whereas the opposite was true for the duration of aural fullness. A longer time since vertigo onset was associated with higher vestibular EH grades; the opposite was true for the duration of individual vertigo attacks. The multiple regression analysis revealed that age, tinnitus duration, and vestibular EH were risk factors for SIR. Furthermore, the low-frequency hearing threshold (HT) was a risk factor for cochlear and vestibular EH, and the SIR. CONCLUSION The EH grade and SIR (an indicator for the quantitative evaluation of PE) were correlated with clinical features and HT of MD; thus, imaging can be a valuable tool in planning individualised treatment. CLINICAL RELEVANCE STATEMENT This study revealed that the grade of endolymphatic hydrops and degree of perilymphatic enhancement positively correlates with the length of time since onset of clinical symptoms and hearing thresholds in patients with Ménière's disease, facilitating the tailored treatment. KEY POINTS • Relationships between 3-dimensional real inversion recovery features and clinical symptoms in Ménière's disease are unknown. • Symptom duration and hearing thresholds correlated with endolymphatic hydrops grades and degree of perilymphatic enhancement. • MRI features correlate with MD severity; thus, imaging is valuable for planning tailored treatment.
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Affiliation(s)
- Jinye Li
- Department of Radiology, Shandong Provincial ENT Hospital, Shandong University, 4 Duan Xing-Xi Road, Jinan, People's Republic of China
| | - Xianwen Jin
- Department of Radiology, Shandong Maternal and Child Health Care Hospital, Jinan, People's Republic of China
| | - Xiao Kong
- Department of Radiology, Shandong Provincial ENT Hospital, Shandong University, 4 Duan Xing-Xi Road, Jinan, People's Republic of China
| | - Na Hu
- Department of Radiology, Shandong Provincial ENT Hospital, Shandong University, 4 Duan Xing-Xi Road, Jinan, People's Republic of China
| | - Xiaoqin Li
- Department of Radiology, Shandong Provincial ENT Hospital, Shandong University, 4 Duan Xing-Xi Road, Jinan, People's Republic of China
| | - Linsheng Wang
- Department of Radiology, Shandong Provincial ENT Hospital, Shandong University, 4 Duan Xing-Xi Road, Jinan, People's Republic of China
| | - Mengxiao Liu
- Diagnostic Imaging, MR scientific Marketing, Siemens Healthineers Ltd, Shanghai, People's Republic of China
| | - Chuanting Li
- Department of Radiology, Shandong Provincial Hospital, Shandong University, Jinan, People's Republic of China
| | - Yafei Liu
- Shandong Mental Health Center, Shandong University, 49 Wenhua Dong Road, Jinan, People's Republic of China.
| | - Lixin Sun
- Department of Radiology, Shandong Provincial ENT Hospital, Shandong University, 4 Duan Xing-Xi Road, Jinan, People's Republic of China.
| | - Ruozhen Gong
- Department of Radiology, Shandong Provincial Hospital, Shandong University, Jinan, People's Republic of China
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Solovev I, Sergeeva A, Geraskina A, Shaposhnikov M, Vedunova M, Borysova O, Moskalev A. Aging and physiological barriers: mechanisms of barrier integrity changes and implications for age-related diseases. Mol Biol Rep 2024; 51:917. [PMID: 39158744 DOI: 10.1007/s11033-024-09833-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2024] [Accepted: 07/30/2024] [Indexed: 08/20/2024]
Abstract
The phenomenon of compartmentalization is one of the key traits of life. Biological membranes and histohematic barriers protect the internal environment of the cell and organism from endogenous and exogenous impacts. It is known that the integrity of these barriers decreases with age due to the loss of homeostasis, including age-related gene expression profile changes and the abnormal folding/assembly, crosslinking, and cleavage of barrier-forming macromolecules in addition to morphological changes in cells and tissues. The critical molecular and cellular mechanisms involved in physiological barrier integrity maintenance and aging-associated changes in their functioning are reviewed on different levels: molecular, organelle, cellular, tissue (histohematic, epithelial, and endothelial barriers), and organ one (skin). Biogerontology, which studies physiological barriers in the aspect of age, is still in its infancy; data are being accumulated, but there is no talk of the synthesis of complex theories yet. This paper mainly presents the mechanisms that will become targets of anti-aging therapy only in the future, possibly: pharmacological, cellular, and gene therapies, including potential geroprotectors, hormetins, senomorphic drugs, and senolytics.
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Affiliation(s)
- Ilya Solovev
- Laboratory of Geroprotective and Radioprotective Technologies, Institute of Biology, Komi Science Center, Ural Branch, Russian Academy of Sciences, 28 Kommunisticheskaya st, Syktyvkar, 167982, Russian Federation
- Pitirim Sorokin Syktyvkar State University, 55 Oktyabrsky prosp, Syktyvkar, 167001, Russian Federation
| | - Alena Sergeeva
- Lobachevsky State University, Nizhny Novgorod, 603022, Russian Federation
| | | | - Mikhail Shaposhnikov
- Laboratory of Geroprotective and Radioprotective Technologies, Institute of Biology, Komi Science Center, Ural Branch, Russian Academy of Sciences, 28 Kommunisticheskaya st, Syktyvkar, 167982, Russian Federation
| | - Maria Vedunova
- Laboratory of genetics and epigenetics of aging, Russian Clinical Research Center for Gerontology, Pirogov Russian National Research Medical University, Moscow, 129226, Russian Federation
| | | | - Alexey Moskalev
- Laboratory of Geroprotective and Radioprotective Technologies, Institute of Biology, Komi Science Center, Ural Branch, Russian Academy of Sciences, 28 Kommunisticheskaya st, Syktyvkar, 167982, Russian Federation.
- Lobachevsky State University, Nizhny Novgorod, 603022, Russian Federation.
- Laboratory of genetics and epigenetics of aging, Russian Clinical Research Center for Gerontology, Pirogov Russian National Research Medical University, Moscow, 129226, Russian Federation.
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4
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Ke Y, Ma X, Jing Y, Diao T, Yu L. The Breakdown of Blood-Labyrinth Barrier Makes it Easier for Drugs to Enter the Inner Ear. Laryngoscope 2024; 134:2377-2386. [PMID: 37987231 DOI: 10.1002/lary.31194] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2023] [Revised: 10/13/2023] [Accepted: 11/06/2023] [Indexed: 11/22/2023]
Abstract
PURPOSE This study aimed to investigate dynamic change of permeability of blood-labyrinth barrier (BLB) after noise exposure and its effect on the drug delivery efficiency of systemic administration. METHODS Gadopentetate dimeglumine (Gd-DTPA) and dexamethasone (DEX) were used as tracers, and magnetic resonance imaging (MRI) and immunofluorescence were used to observe the change of the BLB after strong noise exposure in guinea pigs. High-performance liquid chromatography-mass spectrometry (LC-MS) was used to observe the effect of the breakdown of BLB after noise exposure on the drug delivery efficiency of intravenous DEX. The guinea pigs were divided into 6 groups: normal group (N), 1, 3, 5, 8, and 12 days after noise exposure groups (P1, P3, P5, P8, P12), with 5 animals in each group. RESULTS The BLB changes dynamically after noise exposure. Increased permeability of the blood-endolymph barrier, the endolymph-perilymph barrier, and the blood-nerve barrier was observed at days 1-3, 1-5, and 1-8, respectively, after noise exposure in guinea pigs. Higher drug concentration in the cochlear tissue was obtained by intravenous administration of DEX in guinea pigs during the time window of increased permeability of the BLB. CONCLUSION After noise exposure, the increased BLB permeability makes it easier for drugs to enter the inner ear from blood. In guinea pigs, 1-8 days after strong noise exposure, the drug delivery efficiency of systemic administration increased. After 8 days, the efficiency gradually returned to normal level. 1-8 days after noise exposure may be the best intervention time for systemic administration. LEVEL OF EVIDENCE NA Laryngoscope, 134:2377-2386, 2024.
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Affiliation(s)
- Yujie Ke
- Department of Otorhinolaryngology, Peking University People's Hospital, Beijing, China
| | - Xin Ma
- Department of Otorhinolaryngology, Peking University People's Hospital, Beijing, China
| | - Yuanyuan Jing
- Department of Otorhinolaryngology, Peking University People's Hospital, Beijing, China
| | - Tongxiang Diao
- Department of Otorhinolaryngology, Peking University People's Hospital, Beijing, China
| | - Lisheng Yu
- Department of Otorhinolaryngology, Peking University People's Hospital, Beijing, China
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5
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Huang TL, Jiang WJ, Zhou Z, Shi TF, Yu M, Yu M, Si JQ, Wang YP, Li L. Quercetin attenuates cisplatin-induced mitochondrial apoptosis via PI3K/Akt mediated inhibition of oxidative stress in pericytes and improves the blood labyrinth barrier permeability. Chem Biol Interact 2024; 393:110939. [PMID: 38490643 DOI: 10.1016/j.cbi.2024.110939] [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: 07/14/2023] [Revised: 02/26/2024] [Accepted: 03/04/2024] [Indexed: 03/17/2024]
Abstract
Cisplatin (CDDP) is broadly employed to treat different cancers, whereas there are no drugs approved by the Food and Drug Administration (FDA) for preventing its side effects, including ototoxicity. Quercetin (QU) is a widely available natural flavonoid compound with anti-tumor and antioxidant properties. The research was designed to explore the protective effects of QU on CDDP-induced ototoxicity and its underlying mechanisms in male C57BL/6 J mice and primary cultured pericytes (PCs). Hearing changes, morphological changes of stria vascularis, blood labyrinth barrier (BLB) permeability and expression of apoptotic proteins were observed in vivo by using the auditory brainstem response (ABR) test, HE staining, Evans blue staining, immunohistochemistry, western blotting, etc. Oxidative stress levels, mitochondrial function and endothelial barrier changes were observed in vitro by using DCFH-DA probe detection, flow cytometry, JC-1 probe, immunofluorescence and the establishment in vitro BLB models, etc. QU pretreatment activates the PI3K/AKT signaling pathway, inhibits CDDP-induced oxidative stress, protects mitochondrial function, and reduces mitochondrial apoptosis in PCs. However, PI3K/AKT specific inhibitor (LY294002) partially reverses the protective effects of QU. In addition, in vitro BLB models were established by coculturing PCs and endothelial cells (ECs), which suggests that QU both reduces the CDDP-induced apoptosis in PCs and improves the endothelial barrier permeability. On the whole, the research findings suggest that QU can be used as a novel treatment to reduce CDDP-induced ototoxicity.
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Affiliation(s)
- Tian-Lan Huang
- Department of Physiology, Medical College of Shihezi University, Shihezi, Xinjiang, 832000, China
| | - Wen-Jun Jiang
- Department of Physiology, Zhejiang Chinese Medical University, Hangzhou, Zhejiang, 310051, China; Department of Physiology, Medical College of Jiaxing University, Jiaxing, Zhejiang, 314000, China
| | - Zan Zhou
- Department of Physiology, Medical College of Shihezi University, Shihezi, Xinjiang, 832000, China
| | - Tian-Feng Shi
- Department of Physiology, Medical College of Shihezi University, Shihezi, Xinjiang, 832000, China
| | - Miao Yu
- Department of Physiology, Medical College of Shihezi University, Shihezi, Xinjiang, 832000, China
| | - Meng Yu
- Department of Physiology, Zhejiang Chinese Medical University, Hangzhou, Zhejiang, 310051, China; Department of Physiology, Medical College of Jiaxing University, Jiaxing, Zhejiang, 314000, China
| | - Jun-Qiang Si
- Department of Physiology, Medical College of Shihezi University, Shihezi, Xinjiang, 832000, China
| | - Yan-Ping Wang
- Department of Nursing, Medical College of Jiaxing University, Jiaxing, Zhejiang, 314000, China.
| | - Li Li
- Department of Physiology, Medical College of Jiaxing University, Jiaxing, Zhejiang, 314000, China.
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6
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YAMAGUCHI T, YONEYAMA M, ONAKA Y, OGITA K. A novel model of sensorineural hearing loss induced by repeated exposure to moderate noise in mice: the preventive effect of resveratrol. J Vet Med Sci 2024; 86:381-388. [PMID: 38369331 PMCID: PMC11061573 DOI: 10.1292/jvms.23-0477] [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: 11/24/2023] [Accepted: 02/04/2024] [Indexed: 02/20/2024] Open
Abstract
Sensorineural hearing loss (SNHL) induced by noise has increased in recent years due to personal headphone use and noisy urban environments. The study shows a novel model of gradually progressive SNHL induced by repeated exposure to moderate noise (8-kHz octave band noise, 90-dB sound pressure level) for 1 hr exposure per day in BALB/cCr mice. The results showed that the repeated exposure led to gradually progressive SNHL, which was dependent on the number of exposures, and resulted in permanent hearing loss after 5 exposures. Repeated exposure to noise causes a loss of synapses between the inner hair cells and the peripheral terminals of the auditory nerve fibers. Additionally, there is a reduction in the expression levels of c-fos and Arc, both of which are indicators of cochlear nerve responses to noise exposure. Oral administration of resveratrol (RSV, 50 mg/kg/day) during the noise exposure period significantly prevented the noise exposure-induced synapse loss and SNHL. Furthermore, the study found that RSV treatment prevented the noise-induced increase in the gene expression levels of the proinflammatory cytokine interleukin-1β in the cochlea. These results demonstrated the potential usefulness of RSV in preventing noise-induced SNHL in the animal model established as gradually progressive SNHL.
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Affiliation(s)
- Taro YAMAGUCHI
- Laboratory of Pharmacology, Faculty of Pharmaceutical
Sciences, Setsunan University, Osaka, Japan
| | - Masanori YONEYAMA
- Laboratory of Pharmacology, Faculty of Pharmaceutical
Sciences, Setsunan University, Osaka, Japan
| | - Yusuke ONAKA
- Laboratory of Pharmacology, Faculty of Pharmaceutical
Sciences, Setsunan University, Osaka, Japan
| | - Kiyokazu OGITA
- Faculty of Pharmaceutical Sciences, Setsunan University,
Osaka, Japan
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7
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Coffin AB, Dale E, Molano O, Pederson A, Costa EK, Chen J. Age-related changes in the zebrafish and killifish inner ear and lateral line. Sci Rep 2024; 14:6670. [PMID: 38509148 PMCID: PMC10954678 DOI: 10.1038/s41598-024-57182-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2023] [Accepted: 03/14/2024] [Indexed: 03/22/2024] Open
Abstract
Age-related hearing loss (ARHL) is a debilitating disorder for millions worldwide. While there are multiple underlying causes of ARHL, one common factor is loss of sensory hair cells. In mammals, new hair cells are not produced postnatally and do not regenerate after damage, leading to permanent hearing impairment. By contrast, fish produce hair cells throughout life and robustly regenerate these cells after toxic insult. Despite these regenerative abilities, zebrafish show features of ARHL. Here, we show that aged zebrafish of both sexes exhibited significant hair cell loss and decreased cell proliferation in all inner ear epithelia (saccule, lagena, utricle). Ears from aged zebrafish had increased expression of pro-inflammatory genes and significantly more macrophages than ears from young adult animals. Aged zebrafish also had fewer lateral line hair cells and less cell proliferation than young animals, although lateral line hair cells still robustly regenerated following damage. Unlike zebrafish, African turquoise killifish (an emerging aging model) only showed hair cell loss in the saccule of aged males, but both sexes exhibit age-related changes in the lateral line. Our work demonstrates that zebrafish exhibit key features of auditory aging, including hair cell loss and increased inflammation. Further, our finding that aged zebrafish have fewer lateral line hair cells yet retain regenerative capacity, suggests a decoupling of homeostatic hair cell addition from regeneration following acute trauma. Finally, zebrafish and killifish show species-specific strategies for lateral line homeostasis that may inform further comparative research on aging in mechanosensory systems.
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Affiliation(s)
- Allison B Coffin
- College of Arts and Sciences, Washington State University Vancouver, Vancouver, WA, 98686, USA.
- Department of Integrative Physiology and Neuroscience, Washington State University Vancouver, Vancouver, WA, 98686, USA.
| | - Emily Dale
- College of Arts and Sciences, Washington State University Vancouver, Vancouver, WA, 98686, USA
- Neuroimmunology Research, Mayo Clinic, Rochester, MN, 55902, USA
| | - Olivia Molano
- College of Arts and Sciences, Washington State University Vancouver, Vancouver, WA, 98686, USA
- Neuroscience Graduate Program, Brown University, Providence, RI, 02912, USA
| | - Alexandra Pederson
- College of Arts and Sciences, Washington State University Vancouver, Vancouver, WA, 98686, USA
- Department of Behavioral Neuroscience, Oregon Health & Science University, Portland, OR, 97239, USA
| | - Emma K Costa
- Department of Neurology and Neurological Sciences, Stanford University, Stanford, CA, 94305, USA
- Neurosciences Interdepartmental Program, Stanford University School of Medicine, Stanford, CA, 94305, USA
| | - Jingxun Chen
- Department of Genetics, Stanford University, Stanford, CA, 94305, USA
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8
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Cosentino A, Agafonova A, Modafferi S, Trovato Salinaro A, Scuto M, Maiolino L, Fritsch T, Calabrese EJ, Lupo G, Anfuso CD, Calabrese V. Blood-Labyrinth Barrier in Health and Diseases: Effect of Hormetic Nutrients. Antioxid Redox Signal 2024; 40:542-563. [PMID: 37565276 DOI: 10.1089/ars.2023.0251] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 08/12/2023]
Abstract
Significance: The stria vascularis, located in the inner ear, consists of three layers, one of which is the blood-labyrinth barrier (BLB). It is formed by endothelial cells, sealed together to prevent the passage of toxic substances from the blood to the inner ear, by pericytes and perivascular-resident macrophage-like melanocyte. Recent Advances: There are various causes that lead to hearing loss, and among these are noise-induced and autoimmune hearing loss, ear disorders related to ototoxic medication, Ménière's disease, and age-related hearing loss. For all of these, major therapeutic interventions include drug-loaded nanoparticles, via intratympanic or intracochlear delivery. Critical Issues: Since many pathologies associated with hearing loss are characterized by a weakening of the BLB, in this review, the molecular mechanisms underlying the response to damage of BLB cellular components have been discussed. In addition, insight into the role of hormetic nutrients against hearing loss pathology is proposed. Future Directions: BLB cellular components of neurovascular cochlear unit play important physiological roles, owing to their impermeable function against all ototoxic substances that can induce damage. Studies are needed to investigate the cross talk occurring between these cellular components to exploit their possible role as novel targets for therapeutic interventions that may unravel future path based on the use of hormetic nutrients. Antioxid. Redox Signal. 40, 542-563.
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Affiliation(s)
- Alessia Cosentino
- Section of Medical Biochemistry, Department of Biomedical and Biotechnological Sciences, School of Medicine; Surgical and Advanced Technologies "G. F. Ingrassia"; University of Catania, Catania, Italy
| | - Aleksandra Agafonova
- Section of Medical Biochemistry, Department of Biomedical and Biotechnological Sciences, School of Medicine; Surgical and Advanced Technologies "G. F. Ingrassia"; University of Catania, Catania, Italy
| | - Sergio Modafferi
- Section of Medical Biochemistry, Department of Biomedical and Biotechnological Sciences, School of Medicine; Surgical and Advanced Technologies "G. F. Ingrassia"; University of Catania, Catania, Italy
| | - Angela Trovato Salinaro
- Section of Medical Biochemistry, Department of Biomedical and Biotechnological Sciences, School of Medicine; Surgical and Advanced Technologies "G. F. Ingrassia"; University of Catania, Catania, Italy
| | - Maria Scuto
- Section of Medical Biochemistry, Department of Biomedical and Biotechnological Sciences, School of Medicine; Surgical and Advanced Technologies "G. F. Ingrassia"; University of Catania, Catania, Italy
| | - Luigi Maiolino
- Department of Medical, Surgical and Advanced Technologies "G. F. Ingrassia"; University of Catania, Catania, Italy
| | | | - Edward J Calabrese
- Department of Environmental Health, School of Public Health and Health Sciences, University of Massachusetts, Amherst, Massachusetts, USA
| | - Gabriella Lupo
- Section of Medical Biochemistry, Department of Biomedical and Biotechnological Sciences, School of Medicine; Surgical and Advanced Technologies "G. F. Ingrassia"; University of Catania, Catania, Italy
| | - Carmelina Daniela Anfuso
- Section of Medical Biochemistry, Department of Biomedical and Biotechnological Sciences, School of Medicine; Surgical and Advanced Technologies "G. F. Ingrassia"; University of Catania, Catania, Italy
| | - Vittorio Calabrese
- Section of Medical Biochemistry, Department of Biomedical and Biotechnological Sciences, School of Medicine; Surgical and Advanced Technologies "G. F. Ingrassia"; University of Catania, Catania, Italy
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9
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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] [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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10
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Zhang Y, Ye F, Fu X, Li S, Wang L, Chen Y, Li H, Hao S, Zhao K, Feng Q, Li P. Mitochondrial Regulation of Macrophages in Innate Immunity and Diverse Roles of Macrophages During Cochlear Inflammation. Neurosci Bull 2024; 40:255-267. [PMID: 37391607 PMCID: PMC10838870 DOI: 10.1007/s12264-023-01085-y] [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: 02/14/2023] [Accepted: 05/05/2023] [Indexed: 07/02/2023] Open
Abstract
Macrophages are essential components of the innate immune system and constitute a non-specific first line of host defense against pathogens and inflammation. Mitochondria regulate macrophage activation and innate immune responses in various inflammatory diseases, including cochlear inflammation. The distribution, number, and morphological characteristics of cochlear macrophages change significantly across different inner ear regions under various pathological conditions, including noise exposure, ototoxicity, and age-related degeneration. However, the exact mechanism underlying the role of mitochondria in macrophages in auditory function remains unclear. Here, we summarize the major factors and mitochondrial signaling pathways (e.g., metabolism, mitochondrial reactive oxygen species, mitochondrial DNA, and the inflammasome) that influence macrophage activation in the innate immune response. In particular, we focus on the properties of cochlear macrophages, activated signaling pathways, and the secretion of inflammatory cytokines after acoustic injury. We hope this review will provide new perspectives and a basis for future research on cochlear inflammation.
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Affiliation(s)
- Yuan Zhang
- Department of Otology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, 450052, China
| | - Fanglei Ye
- Department of Otology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, 450052, China
| | - Xiaolong Fu
- Shandong Provincial Hospital, Shandong First Medical University, Jinan, 250000, China
| | - Shen Li
- Department of Neurology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, 450052, China
| | - Le Wang
- Department of Otology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, 450052, China
| | - Yutian Chen
- The Department of Endovascular Surgery, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, 450052, China
| | - Hongmin Li
- Department of Otology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, 450052, China
| | - Shaojuan Hao
- Department of Otology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, 450052, China
| | - Kun Zhao
- Department of Otology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, 450052, China
| | - Qi Feng
- Department of Integrated Traditional and Western Nephrology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, 450052, China.
- Henan Province Research Center of Kidney Disease, Zhengzhou, 450052, China.
| | - Peipei Li
- Department of Integrated Traditional and Western Nephrology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, 450052, China.
- Henan Province Research Center of Kidney Disease, Zhengzhou, 450052, China.
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11
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Shi X. Research advances in cochlear pericytes and hearing loss. Hear Res 2023; 438:108877. [PMID: 37651921 PMCID: PMC10538405 DOI: 10.1016/j.heares.2023.108877] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/19/2023] [Revised: 08/03/2023] [Accepted: 08/18/2023] [Indexed: 09/02/2023]
Abstract
Pericytes are specialized mural cells surrounding endothelial cells in microvascular beds. They play a role in vascular development, blood flow regulation, maintenance of blood-tissue barrier integrity, and control of angiogenesis, tissue fibrosis, and wound healing. In recent decades, understanding of the critical role played by pericytes in retina, brain, lung, and kidney has seen significant progress. The cochlea contains a large population of pericytes. However, the role of cochlear pericytes in auditory pathophysiology is, by contrast, largely unknown. The present review discusses recent progress in identifying cochlear pericytes, mapping their distribution, and defining their role in regulating blood flow, controlling the blood-labyrinth barrier (BLB) and angiogenesis, and involvement in different types of hearing loss.
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Affiliation(s)
- Xiaorui Shi
- Department of Otolaryngology/Head & Neck Surgery, Oregon Hearing Research Center (NRC04), Oregon Health & Science University, 3181 SW Sam Jackson Park Road, Portland, OR 97239-3098, USA.
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12
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Lang H, Noble KV, Barth JL, Rumschlag JA, Jenkins TR, Storm SL, Eckert MA, Dubno JR, Schulte BA. The Stria Vascularis in Mice and Humans Is an Early Site of Age-Related Cochlear Degeneration, Macrophage Dysfunction, and Inflammation. J Neurosci 2023; 43:5057-5075. [PMID: 37268417 PMCID: PMC10324995 DOI: 10.1523/jneurosci.2234-22.2023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2022] [Revised: 04/19/2023] [Accepted: 05/25/2023] [Indexed: 06/04/2023] Open
Abstract
Age-related hearing loss, or presbyacusis, is a common degenerative disorder affecting communication and quality of life for millions of older adults. Multiple pathophysiologic manifestations, along with many cellular and molecular alterations, have been linked to presbyacusis; however, the initial events and causal factors have not been clearly established. Comparisons of the transcriptome in the lateral wall (LW) with other cochlear regions in a mouse model (of both sexes) of "normal" age-related hearing loss revealed that early pathophysiological alterations in the stria vascularis (SV) are associated with increased macrophage activation and a molecular signature indicative of inflammaging, a common form of immune dysfunction. Structure-function correlation analyses in mice across the lifespan showed that the age-dependent increase in macrophage activation in the stria vascularis is associated with a decline in auditory sensitivity. High-resolution imaging analysis of macrophage activation in middle-aged and aged mouse and human cochleas, along with transcriptomic analysis of age-dependent changes in mouse cochlear macrophage gene expression, support the hypothesis that aberrant macrophage activity is an important contributor to age-dependent strial dysfunction, cochlear pathology, and hearing loss. Thus, this study highlights the SV as a primary site of age-related cochlear degeneration and aberrant macrophage activity and dysregulation of the immune system as early indicators of age-related cochlear pathology and hearing loss. Importantly, novel new imaging methods described here now provide a means to analyze human temporal bones in a way that had not previously been feasible and thereby represent a significant new tool for otopathological evaluation.SIGNIFICANCE STATEMENT Age-related hearing loss is a common neurodegenerative disorder affecting communication and quality of life. Current interventions (primarily hearing aids and cochlear implants) offer imperfect and often unsuccessful therapeutic outcomes. Identification of early pathology and causal factors is crucial for the development of new treatments and early diagnostic tests. Here, we find that the SV, a nonsensory component of the cochlea, is an early site of structural and functional pathology in mice and humans that is characterized by aberrant immune cell activity. We also establish a new technique for evaluating cochleas from human temporal bones, an important but understudied area of research because of a lack of well-preserved human specimens and difficult tissue preparation and processing approaches.
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Affiliation(s)
- Hainan Lang
- Department of Pathology and Laboratory Medicine, Medical University of South Carolina, Charleston, South Carolina 29425
| | - Kenyaria V Noble
- Department of Pathology and Laboratory Medicine, Medical University of South Carolina, Charleston, South Carolina 29425
| | - Jeremy L Barth
- Department of Regenerative Medicine and Cell Biology, Medical University of South Carolina, Charleston, South Carolina 29425
| | - Jeffrey A Rumschlag
- Department of Pathology and Laboratory Medicine, Medical University of South Carolina, Charleston, South Carolina 29425
| | - Tyreek R Jenkins
- Department of Pathology and Laboratory Medicine, Medical University of South Carolina, Charleston, South Carolina 29425
| | - Shelby L Storm
- Department of Pathology and Laboratory Medicine, Medical University of South Carolina, Charleston, South Carolina 29425
| | - Mark A Eckert
- Department of Otolaryngology-Head and Neck Surgery, Medical University of South Carolina, Charleston, South Carolina 29425
| | - Judy R Dubno
- Department of Otolaryngology-Head and Neck Surgery, Medical University of South Carolina, Charleston, South Carolina 29425
| | - Bradley A Schulte
- Department of Pathology and Laboratory Medicine, Medical University of South Carolina, Charleston, South Carolina 29425
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13
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Johns JD, Adadey SM, Hoa M. The role of the stria vascularis in neglected otologic disease. Hear Res 2023; 428:108682. [PMID: 36584545 PMCID: PMC9840708 DOI: 10.1016/j.heares.2022.108682] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/18/2022] [Revised: 12/16/2022] [Accepted: 12/19/2022] [Indexed: 12/25/2022]
Abstract
The stria vascularis (SV) has been shown to play a critical role in the pathogenesis of many diseases associated with sensorineural hearing loss (SNHL), including age-related hearing loss (ARHL), noise-induced hearing loss (NIHL), hereditary hearing loss (HHL), and drug-induced hearing loss (DIHL), among others. There are a number of other disorders of hearing loss that may be relatively neglected due to being underrecognized, poorly understood, lacking robust diagnostic criteria or effective treatments. A few examples of these diseases include autoimmune inner ear disease (AIED) and/or autoinflammatory inner ear disease (AID), Meniere's disease (MD), sudden sensorineural hearing loss (SSNHL), and cytomegalovirus (CMV)-related hearing loss (CRHL). Although these diseases may often differ in etiology, there have been recent studies that support the involvement of the SV in the pathogenesis of many of these disorders. We strive to highlight a few prominent examples of these frequently neglected otologic diseases and illustrate the relevance of understanding SV composition, structure and function with regards to these disease processes. In this study, we review the physiology of the SV, lay out the importance of these neglected otologic diseases, highlight the current literature regarding the role of the SV in these disorders, and discuss the current strategies, both approved and investigational, for management of these disorders.
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Affiliation(s)
- J Dixon Johns
- Department of Otolaryngology-Head and Neck Surgery, Georgetown University School of Medicine, Washington, DC, USA.
| | - Samuel M Adadey
- Auditory Development and Restoration Program, National Institute on Deafness and Other Communication Disorders, National Institutes of Health, Bethesda, MD, USA.
| | - Michael Hoa
- Department of Otolaryngology-Head and Neck Surgery, Georgetown University School of Medicine, Washington, DC, USA; Auditory Development and Restoration Program, National Institute on Deafness and Other Communication Disorders, National Institutes of Health, Bethesda, MD, USA.
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14
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Zhang Y, Neng L, Sharma K, Hou Z, Johnson A, Song J, Dabdoub A, Shi X. Pericytes control vascular stability and auditory spiral ganglion neuron survival. eLife 2023; 12:e83486. [PMID: 36719173 PMCID: PMC9940910 DOI: 10.7554/elife.83486] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2022] [Accepted: 01/26/2023] [Indexed: 02/01/2023] Open
Abstract
The inner ear has a rich population of pericytes, a multi-functional mural cell essential for sensory hair cell heath and normal hearing. However, the mechanics of how pericytes contribute to the homeostasis of the auditory vascular-neuronal complex in the spiral ganglion are not yet known. In this study, using an inducible and conditional pericyte depletion mouse (PDGFRB-CreERT2; ROSA26iDTR) model, we demonstrate, for the first time, that pericyte depletion causes loss of vascular volume and spiral ganglion neurons (SGNs) and adversely affects hearing sensitivity. Using an in vitro trans-well co-culture system, we show pericytes markedly promote neurite and vascular branch growth in neonatal SGN explants and adult SGNs. The pericyte-controlled neural growth is strongly mediated by pericyte-released exosomes containing vascular endothelial growth factor-A (VEGF-A). Treatment of neonatal SGN explants or adult SGNs with pericyte-derived exosomes significantly enhances angiogenesis, SGN survival, and neurite growth, all of which were inhibited by a selective blocker of VEGF receptor 2 (Flk1). Our study demonstrates that pericytes in the adult ear are critical for vascular stability and SGN health. Cross-talk between pericytes and SGNs via exosomes is essential for neuronal and vascular health and normal hearing.
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Affiliation(s)
- Yunpei Zhang
- Oregon Hearing Research Center, Department of Otolaryngology/Head & Neck Surgery, Oregon Health & Science UniversityPortlandUnited States
| | - Lingling Neng
- Oregon Hearing Research Center, Department of Otolaryngology/Head & Neck Surgery, Oregon Health & Science UniversityPortlandUnited States
| | - Kushal Sharma
- Oregon Hearing Research Center, Department of Otolaryngology/Head & Neck Surgery, Oregon Health & Science UniversityPortlandUnited States
| | - Zhiqiang Hou
- Oregon Hearing Research Center, Department of Otolaryngology/Head & Neck Surgery, Oregon Health & Science UniversityPortlandUnited States
| | - Anatasiya Johnson
- Oregon Hearing Research Center, Department of Otolaryngology/Head & Neck Surgery, Oregon Health & Science UniversityPortlandUnited States
| | - Junha Song
- Life Sciences Division, Lawrence Berkeley National LaboratoryBerkeleyUnited States
| | - Alain Dabdoub
- Biological Sciences, Sunnybrook Research InstituteTorontoCanada
- Department of Otolaryngology-Head & Neck Surgery, University of TorontoTorontoCanada
- Department of Laboratory Medicine and Pathobiology, University of TorontoTorontoCanada
| | - Xiaorui Shi
- Oregon Hearing Research Center, Department of Otolaryngology/Head & Neck Surgery, Oregon Health & Science UniversityPortlandUnited States
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15
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Li P, Qian T, Sun S. Spatial architecture of the cochlear immune microenvironment in noise-induced and age-related sensorineural hearing loss. Int Immunopharmacol 2023; 114:109488. [PMID: 36470117 DOI: 10.1016/j.intimp.2022.109488] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2022] [Revised: 11/16/2022] [Accepted: 11/21/2022] [Indexed: 12/12/2022]
Abstract
The cochlea encodes sound stimuli and transmits them to the central nervous system, and damage to sensory cells and synapses in the cochlea leads to hearing loss. The inner ear was previously considered to be an immune privileged organ to protect the auditory organ from reactions with the immune system. However, recent studies have revealed the presence of resident macrophages in the cochlea, especially in the spiral ligament, spiral ganglion, and stria vascularis. The tissue-resident macrophages are responsible for the detection, phagocytosis, and clearance of cellular debris and pathogens from the tissues, and they initiate inflammation and influence tissue repair by producing inflammatory cytokines and chemokines. Insult to the cochlea can activate the cochlear macrophages to initiate immune responses. In this review, we describe the distribution and functions of cochlear macrophages in noise-induced hearing impairment and age-related hearing disabilities. We also focus on potential therapeutic interventions concerning hearing loss by modulating local immune responses.
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Affiliation(s)
- Peifan Li
- ENT Institute and Otorhinolaryngology, Department of Affiliated Eye and ENT Hospital, Key Laboratory of Hearing Medicine of NHFPC, State Key Laboratory of Medical Neurobiology, Fudan University, Shanghai, 200031, China; Eye and ENT Hospital, Fudan University, Shanghai, 200031, China
| | - Tingting Qian
- ENT Institute and Otorhinolaryngology, Department of Affiliated Eye and ENT Hospital, Key Laboratory of Hearing Medicine of NHFPC, State Key Laboratory of Medical Neurobiology, Fudan University, Shanghai, 200031, China; Eye and ENT Hospital, Fudan University, Shanghai, 200031, China
| | - Shan Sun
- ENT Institute and Otorhinolaryngology, Department of Affiliated Eye and ENT Hospital, Key Laboratory of Hearing Medicine of NHFPC, State Key Laboratory of Medical Neurobiology, Fudan University, Shanghai, 200031, China; Eye and ENT Hospital, Fudan University, Shanghai, 200031, China.
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16
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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] [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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17
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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] [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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18
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Sekulic-Jablanovic M, Paproth J, Sgambato C, Albano G, Fuster DG, Bodmer D, Petkovic V. Lack of NHE6 and Inhibition of NKCC1 Associated With Increased Permeability in Blood Labyrinth Barrier-Derived Endothelial Cell Layer. Front Cell Neurosci 2022; 16:862119. [PMID: 35496913 PMCID: PMC9039518 DOI: 10.3389/fncel.2022.862119] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2022] [Accepted: 03/17/2022] [Indexed: 12/20/2022] Open
Abstract
Acoustic trauma, autoimmune inner ear disease, and presbycusis feature loss of the integrity of the blood-labyrinth barrier (BLB). Normal BLB function depends on endothelial structural integrity, which is supported and maintained by tight junctions and adherens junctions within the microvascular endothelial layer. When these junctions are disrupted, vascular leakage occurs. Tight junctions and adherens junctions are functionally and structurally linked, but the exact signaling pathways underlying their interaction remain unknown. In addition, solute carriers (SC) are essential for optimal exchange through BLB. Previously, we found that SC family member, the sodium–hydrogen exchanger NHE6, was expressed in all wildtype cochlear tissues, and that Nhe6-knockout mice displayed moderate hearing loss. Moreover, NHE6 depletion affected Trk protein turnover and endosomal signaling. Here, we investigated whether NHE6 might impact BLB integrity. We found that Nhe6-knockout, BLB-derived endothelial cells showed reduced expression of major junctional genes: Tjp1, F11r, Ocln, Cdh5, and Cldn5. Co-culturing BLB-derived endothelial cells with pericytes and/or perivascular resident macrophage-like melanocytes in a transwell system showed that monolayers of Nhe6-knockout BLB-derived cells had lower electrical resistance and higher permeability, compared to wildtype endothelial monolayers. Additionally, another SC, NKCC1, which was previously linked to congenital deafness, was downregulated in our Nhe6-knockout mouse model. Blocking NKCC1 with a NKCC1-specific inhibitor, bumetanide, in wildtype BLB-derived endothelial cells also caused the downregulation of major junctional proteins, particularly Tjp1 and F11r, which encode the zonula occludens and junctional adhesion molecule-1 proteins, respectively. Moreover, bumetanide treatment increased cell permeability. In conclusion, we showed that the lack or inhibition of NHE6 or NKCC1 affected the permeability of endothelial BLB-derived cells. These findings suggested that NHE6 and NKCC1 could serve as potential targets for modifying BLB permeability to facilitate drug delivery across the BLB to the cochlea or to protect the cochlea from ototoxic insults.
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Affiliation(s)
- Marijana Sekulic-Jablanovic
- Department of Biomedicine, University Hospital Basel, University of Basel, Basel, Switzerland
- *Correspondence: Marijana Sekulic-Jablanovic,
| | - Jessica Paproth
- Department of Biomedicine, University Hospital Basel, University of Basel, Basel, Switzerland
| | - Cinzia Sgambato
- Department of Biomedicine, University Hospital Basel, University of Basel, Basel, Switzerland
| | - Giuseppe Albano
- Inselspital Bern, Department of Biomedical Research, University of Bern, Bern, Switzerland
| | - Daniel G. Fuster
- Inselspital Bern, Department of Biomedical Research, University of Bern, Bern, Switzerland
| | - Daniel Bodmer
- Department of Biomedicine, University Hospital Basel, University of Basel, Basel, Switzerland
- Clinic for Otolaryngology, Head and Neck Surgery, University Hospital Basel, Basel, Switzerland
| | - Vesna Petkovic
- Department of Biomedicine, University Hospital Basel, University of Basel, Basel, Switzerland
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19
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Thulasiram MR, Ogier JM, Dabdoub A. Hearing Function, Degeneration, and Disease: Spotlight on the Stria Vascularis. Front Cell Dev Biol 2022; 10:841708. [PMID: 35309932 PMCID: PMC8931286 DOI: 10.3389/fcell.2022.841708] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2021] [Accepted: 01/20/2022] [Indexed: 11/21/2022] Open
Abstract
The stria vascularis (SV) is a highly vascularized tissue lining the lateral wall of the cochlea. The SV maintains cochlear fluid homeostasis, generating the endocochlear potential that is required for sound transduction. In addition, the SV acts as an important blood-labyrinth barrier, tightly regulating the passage of molecules from the blood into the cochlea. A healthy SV is therefore vital for hearing function. Degeneration of the SV is a leading cause of age-related hearing loss, and has been associated with several hearing disorders, including Norrie disease, Meniere's disease, Alport syndrome, Waardenburg syndrome, and Cytomegalovirus-induced hearing loss. Despite the SV's important role in hearing, there is still much that remains to be discovered, including cell-specific function within the SV, mechanisms of SV degeneration, and potential protective or regenerative therapies. In this review, we discuss recent discoveries elucidating the molecular regulatory networks of SV function, mechanisms underlying degeneration of the SV, and otoprotective strategies for preventing drug-induced SV damage. We also highlight recent clinical developments for treating SV-related hearing loss and discuss future research trajectories in the field.
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Affiliation(s)
- Matsya R Thulasiram
- Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, ON, Canada
| | - Jacqueline M Ogier
- Biological Sciences, Sunnybrook Research Institute, Sunnybrook Health Sciences Centre, Toronto, ON, Canada
| | - Alain Dabdoub
- Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, ON, Canada
- Biological Sciences, Sunnybrook Research Institute, Sunnybrook Health Sciences Centre, Toronto, ON, Canada
- Department of Otolaryngology–Head and Neck Surgery, University of Toronto, Toronto, ON, Canada
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20
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Bryant D, Pauzuolyte V, Ingham NJ, Patel A, Pagarkar W, Anderson LA, Smith KE, Moulding DA, Leong YC, Jafree DJ, Long DA, Al-Yassin A, Steel KP, Jagger DJ, Forge A, Berger W, Sowden JC, Bitner-Glindzicz M. The timing of auditory sensory deficits in Norrie disease has implications for therapeutic intervention. JCI Insight 2022; 7:148586. [PMID: 35132964 PMCID: PMC8855802 DOI: 10.1172/jci.insight.148586] [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: 02/12/2021] [Accepted: 12/10/2021] [Indexed: 11/29/2022] Open
Abstract
Norrie disease is caused by mutation of the NDP gene, presenting as congenital blindness followed by later onset of hearing loss. Protecting patients from hearing loss is critical for maintaining their quality of life. This study aimed to understand the onset of pathology in cochlear structure and function. By investigating patients and juvenile Ndp-mutant mice, we elucidated the sequence of onset of physiological changes (in auditory brainstem responses, distortion product otoacoustic emissions, endocochlear potential, blood-labyrinth barrier integrity) and determined the cellular, histological, and ultrastructural events leading to hearing loss. We found that cochlear vascular pathology occurs earlier than previously reported and precedes sensorineural hearing loss. The work defines a disease mechanism whereby early malformation of the cochlear microvasculature precedes loss of vessel integrity and decline of endocochlear potential, leading to hearing loss and hair cell death while sparing spiral ganglion cells. This provides essential information on events defining the optimal therapeutic window and indicates that early intervention is needed. In an era of advancing gene therapy and small-molecule technologies, this study establishes Ndp-mutant mice as a platform to test such interventions and has important implications for understanding the progression of hearing loss in Norrie disease.
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Affiliation(s)
- Dale Bryant
- UCL Great Ormond Street Institute of Child Health, University College London, and NIHR Great Ormond Street Hospital Biomedical Research Centre, London, United Kingdom
| | - Valda Pauzuolyte
- UCL Great Ormond Street Institute of Child Health, University College London, and NIHR Great Ormond Street Hospital Biomedical Research Centre, London, United Kingdom
| | - Neil J Ingham
- Wolfson Centre for Age-Related Diseases, King's College London, London, United Kingdom
| | - Aara Patel
- UCL Great Ormond Street Institute of Child Health, University College London, and NIHR Great Ormond Street Hospital Biomedical Research Centre, London, United Kingdom
| | - Waheeda Pagarkar
- Great Ormond Street Hospital, Great Ormond Street, London, United Kingdom
| | - Lucy A Anderson
- UCL Ear Institute, University College London, London, United Kingdom
| | - Katie E Smith
- UCL Ear Institute, University College London, London, United Kingdom
| | - Dale A Moulding
- UCL Great Ormond Street Institute of Child Health, University College London, and NIHR Great Ormond Street Hospital Biomedical Research Centre, London, United Kingdom
| | - Yeh C Leong
- UCL Great Ormond Street Institute of Child Health, University College London, and NIHR Great Ormond Street Hospital Biomedical Research Centre, London, United Kingdom
| | - Daniyal J Jafree
- UCL Great Ormond Street Institute of Child Health, University College London, and NIHR Great Ormond Street Hospital Biomedical Research Centre, London, United Kingdom.,UCL MB/PhD Programme, Faculty of Medical Sciences, University College London, London, United Kingdom
| | - David A Long
- UCL Great Ormond Street Institute of Child Health, University College London, and NIHR Great Ormond Street Hospital Biomedical Research Centre, London, United Kingdom
| | - Amina Al-Yassin
- UCL Great Ormond Street Institute of Child Health, University College London, and NIHR Great Ormond Street Hospital Biomedical Research Centre, London, United Kingdom
| | - Karen P Steel
- Wolfson Centre for Age-Related Diseases, King's College London, London, United Kingdom
| | - Daniel J Jagger
- UCL Ear Institute, University College London, London, United Kingdom
| | - Andrew Forge
- UCL Ear Institute, University College London, London, United Kingdom
| | - Wolfgang Berger
- Institute of Medical Molecular Genetics, University of Zürich, Schlieren, Switzerland.,Neuroscience Center Zurich, University and ETH Zurich, Zurich, Switzerland.,Zurich Center for Integrative Human Physiology (ZIHP), University of Zurich, Zurich, Switzerland
| | - Jane C Sowden
- UCL Great Ormond Street Institute of Child Health, University College London, and NIHR Great Ormond Street Hospital Biomedical Research Centre, London, United Kingdom
| | - Maria Bitner-Glindzicz
- UCL Great Ormond Street Institute of Child Health, University College London, and NIHR Great Ormond Street Hospital Biomedical Research Centre, London, United Kingdom
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21
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Noble K, Brown L, Elvis P, Lang H. Cochlear Immune Response in Presbyacusis: a Focus on Dysregulation of Macrophage Activity. J Assoc Res Otolaryngol 2022; 23:1-16. [PMID: 34642854 PMCID: PMC8782976 DOI: 10.1007/s10162-021-00819-x] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2021] [Accepted: 09/25/2021] [Indexed: 02/03/2023] Open
Abstract
Age-related hearing loss, or presbyacusis, is a prominent chronic degenerative disorder that affects many older people. Based on presbyacusis pathology, the degeneration occurs in both sensory and non-sensory cells, along with changes in the cochlear microenvironment. The progression of age-related neurodegenerative diseases is associated with an altered microenvironment that reflects chronic inflammatory signaling. Under these conditions, resident and recruited immune cells, such as microglia/macrophages, have aberrant activity that contributes to chronic neuroinflammation and neural cell degeneration. Recently, researchers identified and characterized macrophages in human cochleae (including those from older donors). Along with the age-related changes in cochlear macrophages in animal models, these studies revealed that macrophages, an underappreciated group of immune cells, may play a critical role in maintaining the functional integrity of the cochlea. Although several studies deciphered the molecular mechanisms that regulate microglia/macrophage dysfunction in multiple neurodegenerative diseases, limited studies have assessed the mechanisms underlying macrophage dysfunction in aged cochleae. In this review, we highlight the age-related changes in cochlear macrophage activities in mouse and human temporal bones. We focus on how complement dysregulation and the nucleotide-binding oligomerization domain-like receptor family pyrin domain containing 3 inflammasome could affect macrophage activity in the aged peripheral auditory system. By understanding the molecular mechanisms that underlie these regulatory systems, we may uncover therapeutic strategies to treat presbyacusis and other forms of sensorineural hearing loss.
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Affiliation(s)
- Kenyaria Noble
- Department of Pathology and Laboratory Medicine, Medical University of South Carolina, Charleston, SC, 29425, USA
- Akouos, Inc, Boston, MA, 02210, USA
| | - LaShardai Brown
- Department of Pathology and Laboratory Medicine, Medical University of South Carolina, Charleston, SC, 29425, USA
- Department of Biology, Winthrop University, Rock Hill, SD, 29733, USA
| | - Phillip Elvis
- Department of Pathology and Laboratory Medicine, Medical University of South Carolina, Charleston, SC, 29425, USA
| | - Hainan Lang
- Department of Pathology and Laboratory Medicine, Medical University of South Carolina, Charleston, SC, 29425, USA.
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22
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Kociszewska D, Chan J, Thorne PR, Vlajkovic SM. The Link between Gut Dysbiosis Caused by a High-Fat Diet and Hearing Loss. Int J Mol Sci 2021; 22:13177. [PMID: 34947974 PMCID: PMC8708400 DOI: 10.3390/ijms222413177] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2021] [Revised: 12/02/2021] [Accepted: 12/06/2021] [Indexed: 12/17/2022] Open
Abstract
This review aims to provide a conceptual and theoretical overview of the association between gut dysbiosis and hearing loss. Hearing loss is a global health issue; the World Health Organisation (WHO) estimates that 2.5 billion people will be living with some degree of hearing loss by 2050. The aetiology of sensorineural hearing loss (SNHL) is complex and multifactorial, arising from congenital and acquired causes. Recent evidence suggests that impaired gut health may also be a risk factor for SNHL. Inflammatory bowel disease (IBD), type 2 diabetes, diet-induced obesity (DIO), and high-fat diet (HFD) all show links to hearing loss. Previous studies have shown that a HFD can result in microangiopathy, impaired insulin signalling, and oxidative stress in the inner ear. A HFD can also induce pathological shifts in gut microbiota and affect intestinal barrier (IB) integrity, leading to a leaky gut. A leaky gut can result in chronic systemic inflammation, which may affect extraintestinal organs. Here, we postulate that changes in gut microbiota resulting from a chronic HFD and DIO may cause a systemic inflammatory response that can compromise the permeability of the blood-labyrinth barrier (BLB) in the inner ear, thus inducing cochlear inflammation and hearing deficits.
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Affiliation(s)
| | | | | | - Srdjan M. Vlajkovic
- Department of Physiology and The Eisdell Moore Centre, Faculty of Medical and Health Sciences, The University of Auckland, Private Bag, Auckland 1142, New Zealand; (D.K.); (J.C.); (P.R.T.)
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23
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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: 26] [Impact Index Per Article: 8.7] [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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24
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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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25
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Zhang C, Frye MD, Riordan J, Sharma A, Manohar S, Salvi R, Sun W, Hu BH. Loss of CX3CR1 augments neutrophil infiltration into cochlear tissues after acoustic overstimulation. J Neurosci Res 2021; 99:2999-3020. [PMID: 34520571 DOI: 10.1002/jnr.24925] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2020] [Revised: 06/16/2021] [Accepted: 07/02/2021] [Indexed: 12/20/2022]
Abstract
The cochlea, the sensory organ for hearing, has a protected immune environment, segregated from the systemic immune system by the blood-labyrinth barrier. Previous studies have revealed that acute acoustic injury causes the infiltration of circulating leukocytes into the cochlea. However, the molecular mechanisms controlling immune cell trafficking are poorly understood. Here, we report the role of CX3CR1 in regulating the entry of neutrophils into the cochlea after acoustic trauma. We employed B6.129P-Cx3cr1tm1Litt /J mice, a transgenic strain that lacks the gene, Cx3cr1, for coding the fractalkine receptor. Our results demonstrate that lack of Cx3cr1 results in the augmentation of neutrophil infiltration into cochlear tissues after exposure to an intense noise of 120 dB SPL for 1 hr. Neutrophil distribution in the cochlea is site specific, and the infiltration level is positively associated with noise intensity. Moreover, neutrophils are short lived and macrophage phagocytosis plays a role in neutrophil clearance, consistent with typical neutrophil dynamics in inflamed non-cochlear tissues. Importantly, our study reveals the potentiation of noise-induced hearing loss and sensory cell loss in Cx3cr1-/- mice. In wild-type control mice (Cx3cr1+/+ ) exposed to the same noise, we also found neutrophils. However, neutrophils were present primarily inside the microvessels of the cochlea, with only a few in the cochlear tissues. Collectively, our data implicate CX3CR1-mediated signaling in controlling neutrophil migration from the circulation into cochlear tissues and provide a better understanding of the impacts of neutrophils on cochlear responses to acoustic injury.
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Affiliation(s)
- Celia Zhang
- Center for Hearing and Deafness, University at Buffalo, Buffalo, NY, USA.,Department of Audiology, School of Health Sciences, University of the Pacific, San Francisco, CA, USA
| | - Mitchell D Frye
- Center for Hearing and Deafness, University at Buffalo, Buffalo, NY, USA
| | - Juliana Riordan
- Center for Hearing and Deafness, University at Buffalo, Buffalo, NY, USA
| | - Ashu Sharma
- Department of Oral Biology, School of Dental Medicine, University of Buffalo, The State University of New York, Buffalo, NY, USA
| | | | - Richard Salvi
- Center for Hearing and Deafness, University at Buffalo, Buffalo, NY, USA
| | - Wei Sun
- Center for Hearing and Deafness, University at Buffalo, Buffalo, NY, USA
| | - Bo Hua Hu
- Center for Hearing and Deafness, University at Buffalo, Buffalo, NY, USA
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26
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Zhang Y, Li Y, Fu X, Wang P, Wang Q, Meng W, Wang T, Yang J, Chai R. The Detrimental and Beneficial Functions of Macrophages After Cochlear Injury. Front Cell Dev Biol 2021; 9:631904. [PMID: 34458249 PMCID: PMC8385413 DOI: 10.3389/fcell.2021.631904] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2020] [Accepted: 07/14/2021] [Indexed: 12/20/2022] Open
Abstract
Macrophages are the main intrinsic immune cells in the cochlea; they can be activated and play a complicated role after cochlear injury. Many studies have shown that the number of macrophages and their morphological characteristics within the major cochlear partitions undergo significant changes under various pathological conditions including acoustic trauma, ototoxic drug treatment, age-related cochlear degeneration, selective hair cell (HC) and spiral ganglion neuron (SGN) elimination, and surgery. However, the exact role of these macrophages after cochlear injury is still unclear. Regulating the migration and activity of macrophages may be a therapeutic approach to reduce the risk or magnitude of trauma-induced hearing loss, and this review highlights the role of macrophages on the peripheral auditory structures of the cochlea and elucidate the mechanisms of macrophage injury and the strategies to reduce the injury by regulating macrophage.
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Affiliation(s)
- Yuan Zhang
- MOE Key Laboratory for Developmental Genes and Human Disease, Jiangsu Province High-Tech Key Laboratory for Bio-Medical Research, School of Life Sciences and Technology, Southeast University, Nanjing, China.,Department of Otolaryngology Head and Neck, Nanjing Tongren Hospital, School of Medicine, Southeast University, Nanjing, China.,Co-innovation Center of Neuroregeneration, Nantong University, Nantong, China
| | - Yiyuan Li
- MOE Key Laboratory for Developmental Genes and Human Disease, Jiangsu Province High-Tech Key Laboratory for Bio-Medical Research, School of Life Sciences and Technology, Southeast University, Nanjing, China
| | - Xiaolong Fu
- MOE Key Laboratory for Developmental Genes and Human Disease, Jiangsu Province High-Tech Key Laboratory for Bio-Medical Research, School of Life Sciences and Technology, Southeast University, Nanjing, China
| | - Pengjun Wang
- Department of Otorhinolaryngology, Affiliated Sixth People's Hospital of Shanghai Jiao Tong University, Shanghai, China
| | - Qin Wang
- Department of Otolaryngology-Head and Neck Surgery, The Second Xiangya Hospital, Central South University, Changsha, China
| | - Wei Meng
- Department of Otolaryngology Head and Neck, Nanjing Tongren Hospital, School of Medicine, Southeast University, Nanjing, China
| | - Tian Wang
- Department of Otolaryngology-Head and Neck Surgery, The Second Xiangya Hospital, Central South University, Changsha, China
| | - Jianming Yang
- Department of Otorhinolaryngology, The Second Affiliated Hospital of Anhui Medical University, Hefei, China
| | - Renjie Chai
- MOE Key Laboratory for Developmental Genes and Human Disease, Jiangsu Province High-Tech Key Laboratory for Bio-Medical Research, School of Life Sciences and Technology, Southeast University, Nanjing, China.,Co-innovation Center of Neuroregeneration, Nantong University, Nantong, China.,Institute for Stem Cell and Regeneration, Chinese Academy of Sciences, Beijing, China
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27
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Culhaoglu B, Erbek SS, İnce DA, Ecevit AN, Erbek S. Medial olivary complex reflex in term newborns with hyperbilirubinemia. Int J Pediatr Otorhinolaryngol 2021; 147:110777. [PMID: 34116320 DOI: 10.1016/j.ijporl.2021.110777] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/29/2020] [Revised: 03/21/2021] [Accepted: 05/17/2021] [Indexed: 11/24/2022]
Abstract
OBJECTIVE This study aimed to compare the integrity of the efferent auditory pathways of newborns that had high hyperbilirubinemia levels and required treatment due to these and healthy newborns. METHODS Term-born (37 weeks or later) infants that were brought to the Newborn Polyclinic of the Başkent University Hospital were included in the study. The study included a total of 84 infants including healthy newborns (n = 42) and those that had jaundice and were receiving phototherapy (n = 42). After conducting a general otorhinolaryngology examination on all newborns included in the study, Transient Otoacoustic Emission (TEOAE) test was carried out in the absence and presence of contralateral noise. The obtained contralateral suppression values were compared between the two groups. RESULTS In the TEOAE test, the responses obtained at 1 kHz in the newborns receiving phototherapy were found to be lower. The difference between the groups was significant (p = 0.038). The rates of suppression presence at 2 kHz, 2.8 kHz and total OAE were found significantly higher (p < 0.05) in the group not receiving phototherapy. Among the phototherapy-receiving infants, the hyperbilirubinemia levels of the infants in whom suppression was obtained in the contralateral suppression test did not show a statistically significant difference in comparison to those in whom suppression was not obtained (p > 0.05). CONCLUSION Based on the obtained data, hyperbilirubinemia may have a disruptive effect on the efferent auditory system in newborns. Consequently, we are of the opinion that, in addition to hearing screening in risky newborn infants, a MOC suppression test would be useful.
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Affiliation(s)
- Belde Culhaoglu
- Dept. of Otolaryngology, Faculty of Medicine, Baskent University, Ankara, Turkey.
| | - Selim S Erbek
- Dept. of Otolaryngology, Faculty of Medicine, Baskent University, Ankara, Turkey
| | - Deniz Anuk İnce
- Dept. of Pediatric Neonatology, Faculty of Medicine, Baskent University, Ankara, Turkey
| | - Ayşe Nur Ecevit
- Dept. of Pediatric Neonatology, Faculty of Medicine, Baskent University, Ankara, Turkey
| | - Seyra Erbek
- Dept. of Otolaryngology, Faculty of Medicine, Baskent University, Ankara, Turkey
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28
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Zhang J, Fan W, Neng L, Chen B, Zuo B, Lu W. Long non-coding RNA Rian promotes the expression of tight junction proteins in endothelial cells by regulating perivascular-resident macrophage-like melanocytes and PEDF secretion. Hum Cell 2021; 34:1093-1102. [PMID: 33768511 DOI: 10.1007/s13577-021-00521-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2021] [Accepted: 03/12/2021] [Indexed: 12/20/2022]
Abstract
Perivascular-resident macrophage-like melanocytes (PVM/Ms) can upregulate the expression of tight junction-related proteins in endothelial cells (ECs) by secreting pigment epithelial-derived factor (PEDF), and thereby regulate the permeability of the intrastrial fluid-blood barrier critical for maintaining inner ear homeostasis. This study aimed to investigate the effects of long non-coding RNA (lncRNA) Rian on cell growth of PVM/Ms and PVM/Ms regulation of intrastrial fluid-blood barrier integrity mediated by PEDF. Rian was downregulated in the aged cochlea from 12-month-old C57BL/6 mice. Rian overexpression inhibited cell apoptosis and promoted cell viability of hypoxia-injured PVM/Ms as well as increased the concentration and expression of PEDF secreted by PVM/Ms. In contrast, Rian silencing exerted the opposite effects. Furthermore, in a cell co-culture model of ECs and PVM/Ms, Rian overexpression in PVM/Ms increased the expression of the junction-associated proteins in co-cultured ECs, and this effect was abrogated by blockade of PEDF by anti-PEDF in PVM/Ms. Further mechanistical investigation revealed that Rian promoted STAT3 nuclear translocation and activation by binding to FUS, and thereby promoted the secretion of PEDF. Collectively, Rian attenuates PVM/Ms injury and strengthens the ability of PVM/Ms to maintain the integrity of the endothelial barrier by promoting PEDF expression.
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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, China.
| | - Wenya Fan
- Department of Otorhinolaryngology, Head and Neck Surgery, The First Affiliated Hospital of Zhengzhou University, No 1 Jianshe Road, Zhengzhou, 450052, China
| | - Lingling Neng
- Department of Otorhinolaryngology, Head and Neck Surgery, The First Affiliated Hospital of Zhengzhou University, No 1 Jianshe Road, Zhengzhou, 450052, China
| | - Bei Chen
- Department of Otorhinolaryngology, Head and Neck Surgery, The First Affiliated Hospital of Zhengzhou University, No 1 Jianshe Road, Zhengzhou, 450052, China
| | - Bin Zuo
- Department of Otorhinolaryngology, Head and Neck Surgery, The First Affiliated Hospital of Zhengzhou University, No 1 Jianshe Road, Zhengzhou, 450052, China
| | - Wei Lu
- Department of Otorhinolaryngology, Head and Neck Surgery, The First Affiliated Hospital of Zhengzhou University, No 1 Jianshe Road, Zhengzhou, 450052, China.
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29
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30
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Zhang J, Wang X, Hou Z, Neng L, Cai J, Zhang Y, Shi X. Suppression of Connexin 43 Leads to Strial Vascular Hyper-Permeability, Decrease in Endocochlear Potential, and Mild Hearing Loss. Front Physiol 2020; 11:974. [PMID: 32922309 PMCID: PMC7457066 DOI: 10.3389/fphys.2020.00974] [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: 04/06/2020] [Accepted: 07/16/2020] [Indexed: 12/20/2022] Open
Abstract
Objective: Connexin 43 (Cx43) is a protein constituent of gap junctions (GJs) in various barrier cells, especially astrocytes and microglia of the blood-brain-barrier (BBB), where it plays an important role in intercellular communication and regulation of the barrier. Despite the importance of Cx43 in other blood barriers, not much attention has been paid to expression and function of Cx43 in the blood-labyrinth-barrier (BLB) of the stria vascularis in the cochlea. Methods: We used multiple research approaches, including immunocytochemical staining, patch-clamp dye loading technique, real-time quantitative reverse transcription (RT)-PCR, western blot, measurement of endocochlear potential (EP) with an electrode through the scala media, and auditory brainstem response to test hearing function. Results: We found Cx43 expressed in vascular endothelial cells (ECs) and perivascular resident macrophages (PVMs) in the stria vascularis of adult C57BL/6 mouse cochleae. In particular, we found Cx43 expressed in foot processes of PVMs at points of contact with the endothelium. Consistent with Cx43 expression in vivo, we also found Cx43 expressed in EC-EC and EC-PVM interfaces in a co-cultured cell line model. Using a patch-clamp dye loading technique, we demonstrated that Alexa Fluor® 568 dye injected into PVMs diffuses to connected neighboring ECs. The functional coupling between the ECs and PVMs is blocked by 18α-Glycyrrhetinic acid (18α-GA), a GJ blocker. Suppression of Cx43 with small interfering RNA (siRNA) in vivo significantly elevated hearing threshold and caused the EP to drop and the blood barrier to become more permeable. In further study, using in vitro primary EC cell line models, we demonstrated that suppression of Cx43 disrupts intercellular tight junctions (TJs) in the EC monolayer and increases endothelial monolayer permeability. Conculsion: Taken together, these findings underscore the importance of Cx43 expression in the normal ear for maintaining BLB integrity, normal EP, and hearing function.
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Affiliation(s)
- Jinhui Zhang
- Oregon Hearing Research Center, Oregon Health & Science University, Portland, OR, United States
| | - Xiaohan Wang
- Oregon Hearing Research Center, Oregon Health & Science University, Portland, OR, United States
- Boston Children’s Hospital, Harvard Medical School, Boston, MA, United States
| | - Zhiqiang Hou
- Oregon Hearing Research Center, Oregon Health & Science University, Portland, OR, United States
| | - Lingling Neng
- Oregon Hearing Research Center, Oregon Health & Science University, Portland, OR, United States
| | - Jing Cai
- Oregon Hearing Research Center, Oregon Health & Science University, Portland, OR, United States
| | - Yunpei Zhang
- Oregon Hearing Research Center, Oregon Health & Science University, Portland, OR, United States
| | - Xiaorui Shi
- Oregon Hearing Research Center, Oregon Health & Science University, Portland, OR, United States
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31
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Hou Z, Neng L, Zhang J, Cai J, Wang X, Zhang Y, Lopez IA, Shi X. Acoustic Trauma Causes Cochlear Pericyte-to-Myofibroblast-Like Cell Transformation and Vascular Degeneration, and Transplantation of New Pericytes Prevents Vascular Atrophy. THE AMERICAN JOURNAL OF PATHOLOGY 2020; 190:1943-1959. [PMID: 32562655 DOI: 10.1016/j.ajpath.2020.05.019] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/10/2020] [Revised: 05/19/2020] [Accepted: 05/26/2020] [Indexed: 12/20/2022]
Abstract
Acoustic trauma disrupts cochlear blood flow and damages sensory hair cells. Damage and regression of capillaries after acoustic trauma have long been observed, but the underlying mechanism of pathology has not been understood. We show herein that loud sound causes change of phenotype from neural/glial antigen 2 positive/α-smooth muscle actin negative to neural/glial antigen 2 positive/α-smooth muscle actin positive in some pericytes (PCs) on strial capillaries that is strongly associated with up-regulation of transforming growth factor-β1. The acoustic trauma also reduced capillary density and increased deposition of matrix proteins, particularly in the vicinity of transformed PCs. In a newly established in vitro three-dimensional endothelial cell (EC) and PC co-culture model, transformed PCs induced thicker capillary-like branches in ECs and increased collagen IV and laminin expression. Transplantation of exogenous PCs derived from neonatal day 10 mouse cochleae to acoustic traumatized cochleae, however, significantly attenuated the decreased vascular density in the stria. Transplantation of PCs pretransfected with adeno-associated virus 1-vascular endothelial growth factor-A165 under control of a hypoxia-response element markedly promotes vascular volume and blood flow, increased proliferation of PCs and ECs, and attenuated loud sound-caused loss in endocochlear potential and hearing. Our results indicate that loud sound-triggered PC transformation contributes to capillary wall thickening and regression, and young PC transplantation effectively rehabilitates the vascular regression and improves hearing.
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Affiliation(s)
- Zhiqiang Hou
- Department of Otolaryngology/Head & Neck Surgery, Oregon Hearing Research Center, Oregon Health & Science University, Portland, Oregon
| | - Lingling Neng
- Department of Otolaryngology/Head & Neck Surgery, Oregon Hearing Research Center, Oregon Health & Science University, Portland, Oregon
| | - Jinhui Zhang
- Department of Otolaryngology/Head & Neck Surgery, Oregon Hearing Research Center, Oregon Health & Science University, Portland, Oregon
| | - Jing Cai
- Department of Otolaryngology/Head & Neck Surgery, Oregon Hearing Research Center, Oregon Health & Science University, Portland, Oregon
| | - Xiaohan Wang
- Department of Otolaryngology/Head & Neck Surgery, Oregon Hearing Research Center, Oregon Health & Science University, Portland, Oregon; Center for Life Sciences, Boston Children's Hospital, Harvard Medical School, Boston, Massachusetts
| | - Yunpei Zhang
- Department of Otolaryngology/Head & Neck Surgery, Oregon Hearing Research Center, Oregon Health & Science University, Portland, Oregon
| | - Ivan A Lopez
- Cellular and Molecular Biology of the Inner Ear Laboratory, Department of Head and Neck Surgery, David Geffen School of Medicine at UCLA, Los Angeles, California
| | - Xiaorui Shi
- Department of Otolaryngology/Head & Neck Surgery, Oregon Hearing Research Center, Oregon Health & Science University, Portland, Oregon.
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He W, Yu J, Sun Y, Kong W. Macrophages in Noise-Exposed Cochlea: Changes, Regulation and the Potential Role. Aging Dis 2020; 11:191-199. [PMID: 32010492 PMCID: PMC6961779 DOI: 10.14336/ad.2019.0723] [Citation(s) in RCA: 32] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2019] [Accepted: 07/23/2019] [Indexed: 12/14/2022] Open
Abstract
Acoustic trauma is an important physical factor leading to cochlear damage and hearing impairments. Inflammation responds to this kind of cochlear damage stress. Macrophages, the major innate immune cells in the cochlea, are important drivers of inflammatory and tissue repair responses after cochlear injury. Recently, studies have shown that after noise exposure, the distribution, phenotype, and the number of cochlear macrophages have significantly changed, and the local environmental factors that shape macrophage differentiation and behavior are also drastically altered. However, the exact role of these immune cells in the cochlea after acoustic injury remains unknown. Here we review the properties of cochlear macrophages both under steady-state conditions and non-homeostatic conditions after cochlear acoustic injury and discuss their potential role in noise-exposed cochlea.
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Affiliation(s)
- Weiwei He
- Department of Otorhinolaryngology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430022, China
| | - Jintao Yu
- Department of Otorhinolaryngology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430022, China
| | - Yu Sun
- Department of Otorhinolaryngology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430022, China
| | - Weijia Kong
- Department of Otorhinolaryngology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430022, China
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Abstract
Macrophages are a heterogeneous group of cells that are capable of carrying out distinct functions in different tissues, as well as in different locations within a given tissue. Some of these tissue macrophages lie on, or close to, the outer (abluminal) surface of blood vessels and perform several crucial activities at this interface between the tissue and the blood. In steady-state tissues, these perivascular macrophages maintain tight junctions between endothelial cells and limit vessel permeability, phagocytose potential pathogens before they enter tissues from the blood and restrict inappropriate inflammation. They also have a multifaceted role in diseases such as cancer, Alzheimer disease, multiple sclerosis and type 1 diabetes. Here, we examine the important functions of perivascular macrophages in various adult tissues and describe how these functions are perturbed in a broad array of pathological conditions.
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Zhou Y, Song J, Wang YP, Zhang AM, Tan CY, Liu YH, Zhang ZP, Wang Y, Ma KT, Li L, Si JQ. Age‑associated variation in the expression and function of TMEM16A calcium‑activated chloride channels in the cochlear stria vascularis of guinea pigs. Mol Med Rep 2019; 20:1593-1604. [PMID: 31257512 PMCID: PMC6625423 DOI: 10.3892/mmr.2019.10423] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2018] [Accepted: 05/20/2019] [Indexed: 01/08/2023] Open
Abstract
The present study was designed to investigate the expression and function of transmembrane protein 16 (TMEM16A), a calcium‑activated chloride channel (CaCC), in the stria vascularis (SV) of the cochlea of guinea pigs at different ages, and to understand the role of CaCCs in the pathogenesis of presbycusis (age‑related hearing loss), the most common type of sensorineural hearing loss that occurs with natural aging. Guinea pigs were divided into the following groups: 2 weeks (young group), 3 months (youth group), 1 year (adult group), D‑galactose intervention (D‑gal group; aging model induced by subcutaneous injection of D‑galactose) and T16Ainh‑A01 (intraperitoneal injection of 50 µg/kg/day TMEM16A inhibitor T16Ainh‑A01 for 2 weeks). Differences in the hearing of guinea pigs between the various age groups were analyzed using auditory brainstem response (ABR), and immunofluorescence staining was performed to detect TMEM16A expression in the SV and determine the distribution. Reverse transcription‑quantitative PCR and western blot analyses were conducted to detect the mRNA and protein levels of TMEM16A in SV in the different age groups. Morris water maze behavior analysis demonstrated that spatial learning ability and memory were damaged in the D‑gal group. Superoxide dismutase activity and malondialdehyde content assays indicated that there was oxidative stress damage in the D‑gal group. The ABR thresholds gradually increased with age, and the increase in the T16Ainh‑A01 group was pronounced. Immunofluorescence analysis in the cochlear SV of guinea pigs in different groups revealed that expression of TMEM16A increased with increasing age (2 weeks to 1 year); fluorescence intensity was reduced in the D‑gal model of aging. As the guinea pigs continued to mature, the protein and mRNA contents of TMEM16A in the cochlea SV increased gradually, but were decreased in the D‑gal group. The findings indicated that CaCCs in the cochlear SV of guinea pigs were associated with the development of hearing in guinea pigs, and that downregulation of TMEM16A may be associated with age‑associated hearing loss.
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Affiliation(s)
- Ying Zhou
- Department of Physiology, Medical College of Shihezi University, Shihezi, Xinjiang 832002, P.R. China
| | - Jia Song
- Department of Physiology, Medical College of Shihezi University, Shihezi, Xinjiang 832002, P.R. China
| | - Yan-Ping Wang
- Department of Physiology, Medical College of Shihezi University, Shihezi, Xinjiang 832002, P.R. China
| | - Ai-Mei Zhang
- Department of Physiology, Medical College of Shihezi University, Shihezi, Xinjiang 832002, P.R. China
| | - Chao-Yang Tan
- Department of Physiology, Medical College of Shihezi University, Shihezi, Xinjiang 832002, P.R. China
| | - Yan-Hui Liu
- Department of Physiology, Medical College of Shihezi University, Shihezi, Xinjiang 832002, P.R. China
| | - Zhi-Ping Zhang
- Department of Physiology, Medical College of Shihezi University, Shihezi, Xinjiang 832002, P.R. China
| | - Yang Wang
- Department of Physiology, Medical College of Shihezi University, Shihezi, Xinjiang 832002, P.R. China
| | - Ke-Tao Ma
- Department of Physiology, Medical College of Shihezi University, Shihezi, Xinjiang 832002, P.R. China
| | - Li Li
- Department of Physiology, Medical College of Shihezi University, Shihezi, Xinjiang 832002, P.R. China
| | - Jun-Qiang Si
- Department of Physiology, Medical College of Shihezi University, Shihezi, Xinjiang 832002, P.R. China
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Wang X, Zhang J, Li G, Sai N, Han J, Hou Z, Kachelmeier A, Shi X. Vascular regeneration in adult mouse cochlea stimulated by VEGF-A 165 and driven by NG2-derived cells ex vivo. Hear Res 2019; 377:179-188. [PMID: 30954884 DOI: 10.1016/j.heares.2019.03.010] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/18/2018] [Revised: 02/21/2019] [Accepted: 03/13/2019] [Indexed: 12/20/2022]
Abstract
Can damaged or degenerated vessels be regenerated in the ear? The question is clinically important, as disruption of cochlear blood flow is seen in a wide variety of hearing disorders, including in loud sound-induced hearing loss (endothelial injury), ageing-related hearing loss (lost vascular density), and genetic hearing loss (e.g., Norrie disease: strial avascularization). Progression in cochlear blood flow (CBF) pathology can parallel progression in hair cell and hearing loss. However, neither new vessel growth in the ear, nor the role of angiogenesis in hearing, have been investigated. In this study, we used an established ex vivo tissue explant model in conjunction with a matrigel matrix model to demonstrate for the first time that new vessels can be generated by activating a vascular endothelial growth factor (VEGF-A) signal. Most intriguingly, we found that the pattern of the newly formed vessels resembles the natural 'mesh pattern' of in situ strial vessels, with both lumen and expression of tight junctions. Sphigosine-1-phosphate (S1P) in synergy with VEGF-A control new vessel size and growth. Using transgenic neural/glial antigen 2 (NG2) fluorescent reporter mice, we have furthermore discovered that the progenitors of "de novo" strial vessels are NG2-derived cells. Taken together, our data demonstrates that damaged strial microvessels can be regenerated by reprogramming NG2-derived angiogenic cells. Restoration of the functional vasculature may be critical for recovery of vascular dysfunction related hearing loss.
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Affiliation(s)
- Xiaohan Wang
- Oregon Hearing Research Center, Department of Otolaryngology / Head & Neck Surgery, Oregon Health & Science University, Portland, OR, 97239, USA; Boston Children's Hospital, Harvard Medical School, 25 Shattuck Street, Boston, MA, 02115, USA
| | - Jinhui Zhang
- Oregon Hearing Research Center, Department of Otolaryngology / Head & Neck Surgery, Oregon Health & Science University, Portland, OR, 97239, USA
| | - Guangshuai Li
- Oregon Hearing Research Center, Department of Otolaryngology / Head & Neck Surgery, Oregon Health & Science University, Portland, OR, 97239, USA
| | - Na Sai
- Oregon Hearing Research Center, Department of Otolaryngology / Head & Neck Surgery, Oregon Health & Science University, Portland, OR, 97239, USA
| | - Jiang Han
- Oregon Hearing Research Center, Department of Otolaryngology / Head & Neck Surgery, Oregon Health & Science University, Portland, OR, 97239, USA
| | - Zhiqiang Hou
- Oregon Hearing Research Center, Department of Otolaryngology / Head & Neck Surgery, Oregon Health & Science University, Portland, OR, 97239, USA
| | - Allan Kachelmeier
- Oregon Hearing Research Center, Department of Otolaryngology / Head & Neck Surgery, Oregon Health & Science University, Portland, OR, 97239, USA
| | - Xiaorui Shi
- Oregon Hearing Research Center, Department of Otolaryngology / Head & Neck Surgery, Oregon Health & Science University, Portland, OR, 97239, USA.
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36
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Microvascular networks in the area of the auditory peripheral nervous system. Hear Res 2019; 371:105-116. [DOI: 10.1016/j.heares.2018.11.012] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/04/2018] [Revised: 11/14/2018] [Accepted: 11/28/2018] [Indexed: 12/20/2022]
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Canis M, Bertlich M. Cochlear Capillary Pericytes. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2019; 1122:115-123. [PMID: 30937866 DOI: 10.1007/978-3-030-11093-2_7] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Capillary pericytes in the cochlea of mammals are-compared to pericytes in other tissues, like the CNS-relatively poorly researched. To begin with, there is still a considerable debate as to whether the very last precapillary arterioles should-due to their contractile properties-may be considered to be pericytes.However, cochlear capillary pericytes have shifted into the center of attention in the past decade. Most mammals show a considerable number of pericytes in the stria vascularis of the cochlea-up to 1300 in a mouse alone. This high number may be explained by the observation that cochlear capillary pericytes may be differentiated into different subgroups, depending on the immune markers that are expressed by them. Corresponding with these subpopulations, cochlear pericytes fulfill three core functions in the physiology of the cochlea: Formation of the intrastrial blood-fluid barrier-Pericytes monitor the ion, fluid, and nutrient household and aid in the homeostasis thereof. Regulation of cochlear blood flow-By contraction on relaxation, pericytes contribute to the regulation of cochlear blood flow, a paramount function parameter of the cochlea. Immune response-Pericytes actually contribute to the immune response in inflammation of the cochlea. Due to these central roles in the physiology of the cochlea, pericytes actually play a major role in numerous cochlear pathologies, including, but not limited to, sudden sensorineural hearing loss, acoustic trauma, and inflammation of the cochlea.
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Affiliation(s)
- Martin Canis
- The Department of Otorhinolaryngology, Head and Neck Surgery, University Hospital, Munich, Germany
| | - Mattis Bertlich
- The Department of Otorhinolaryngology, Head and Neck Surgery, University Hospital, Munich, Germany.
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Giurdanella G, Montalbano G, Gennuso F, Brancati S, Lo Furno D, Augello A, Bucolo C, Drago F, Salomone S. Isolation, cultivation, and characterization of primary bovine cochlear pericytes: A new in vitro model of stria vascularis. J Cell Physiol 2018; 234:1978-1986. [PMID: 30317595 DOI: 10.1002/jcp.27545] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2018] [Accepted: 09/14/2018] [Indexed: 12/14/2022]
Abstract
The study of strial pericytes has gained great interest as they are pivotal for the physiology of stria vascularis. To provide an easily accessible in vitro model, here we described a growth medium-based approach to obtain and cultivate primary bovine cochlear pericytes (BCP) from the stria vascularis of explanted bovine cochleae. We obtained high-quality pericytes in 8-10 days with a > 90% purity after the second passage. Immunocytochemical analysis showed a homogeneous population of cells expressing typical pericyte markers, such as neural/glial antigen 2 (NG2), platelet-derived growth factor receptorβ (PDGFRβ), α-smooth muscle actin (α-SMA), and negative for the endothelial marker von Willebrand factor. When challenged with tumor necrosis factor or lipopolysaccharide, BCP changed their shape, similarly to human retinal pericytes (HRPC). The sensitivity of BCP to ototoxic drugs was evaluated by challenging with cisplatin or gentamicin for 48 hr. Compared to human retinal endothelial cells and HRPC, cell viability of BCP was significantly lower ( p < 0.05) after the treatment with gentamicin or cisplatin. These data indicate that our protocol provides a simple and reliable method to obtain highly pure strial BCP. Furthermore, BCP are suitable to assess the safety profile of molecules which supposedly exert ototoxic activity, and may represent a valid alternative to in vivo tests.
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Affiliation(s)
- Giovanni Giurdanella
- Department of Biomedical and Biotechnological Sciences, University of Catania, Catania, Italy
| | - Giuseppe Montalbano
- Department of Veterinary Sciences and Zebrafish Neuromorphology Lab, University of Messina, Messina, Italia
| | - Florinda Gennuso
- Department of Biomedical and Biotechnological Sciences, University of Catania, Catania, Italy
| | - Serena Brancati
- Department of Biomedical and Biotechnological Sciences, University of Catania, Catania, Italy
| | - Debora Lo Furno
- Department of Biomedical and Biotechnological Sciences, University of Catania, Catania, Italy
| | - Antonio Augello
- ASP Catania Dipartimento di Prevenzione Veterinaria, Servizio Igiene degli Alimenti di Origine Animale (SIAOA), Catania, Italy
| | - Claudio Bucolo
- Department of Biomedical and Biotechnological Sciences, University of Catania, Catania, Italy
| | - Filippo Drago
- Department of Biomedical and Biotechnological Sciences, University of Catania, Catania, Italy
| | - Salvatore Salomone
- Department of Biomedical and Biotechnological Sciences, University of Catania, Catania, Italy
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Hou Z, Wang X, Cai J, Zhang J, Hassan A, Auer M, Shi X. Platelet-Derived Growth Factor Subunit B Signaling Promotes Pericyte Migration in Response to Loud Sound in the Cochlear Stria Vascularis. J Assoc Res Otolaryngol 2018; 19:363-379. [PMID: 29869048 PMCID: PMC6081892 DOI: 10.1007/s10162-018-0670-z] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2017] [Accepted: 04/19/2018] [Indexed: 12/20/2022] Open
Abstract
Normal blood supply to the cochlea is critical for hearing. Noise damages auditory sensory cells and has a marked effect on the microvasculature in the cochlear lateral wall. Pericytes in the stria vascularis (strial pericytes) are particularly vulnerable and sensitive to acoustic trauma. Exposure of NG2DsRedBAC transgenic mice (6-8 weeks old) to wide-band noise at a level of 120 dB for 3 h per day for 2 consecutive days produced a significant hearing threshold shift and caused pericytes to protrude and migrate from their normal endothelial attachment sites. The pericyte migration was associated with increased expression of platelet-derived growth factor beta (PDGF-BB). Blockade of PDGF-BB signaling with either imatinib, a potent PDGF-BB receptor (PDGFR) inhibitor, or APB5, a specific PDGFRβ blocker, significantly attenuated the pericyte migration from strial vessel walls. The PDGF-BB-mediated strial pericyte migration was further confirmed in an in vitro cell migration assay, as well as in an in vivo live animal model used in conjunction with confocal fluorescence microscopy. Pericyte migration took one of two different forms, here denoted protrusion and detachment. The protrusion is characterized by pericytes with a prominent triangular shape, or pericytes extending fine strands to neighboring capillaries. The detachment is characterized by pericyte detachment and movement away from vessels. We also found the sites of pericyte migration highly associated with regions of vascular leakage. In particular, under transmission electron microscopy (TEM), multiple vesicles at the sites of endothelial cells with loosely attached pericytes were observed. These data show that cochlear pericytes are markedly affected by acoustic trauma, causing them to display abnormal morphology. The effect of loud sound on pericytes is mediated by upregulation of PDGF-BB. Normal functioning pericytes are required for vascular stability.
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Affiliation(s)
- Zhiqiang Hou
- Oregon Hearing Research Center, Department of Otolaryngology/Head & Neck Surgery, Oregon Health & Science University, Portland, OR, 97239, USA
| | - Xiaohan Wang
- Oregon Hearing Research Center, Department of Otolaryngology/Head & Neck Surgery, Oregon Health & Science University, Portland, OR, 97239, USA
| | - Jing Cai
- Oregon Hearing Research Center, Department of Otolaryngology/Head & Neck Surgery, Oregon Health & Science University, Portland, OR, 97239, USA
| | - Jinhui Zhang
- Oregon Hearing Research Center, Department of Otolaryngology/Head & Neck Surgery, Oregon Health & Science University, Portland, OR, 97239, USA
| | - Ahmed Hassan
- Department of Biomedical Engineering, The University of Texas at Austin, Austin, TX, 78712, USA
| | - Manfred Auer
- Life Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, USA
| | - Xiaorui Shi
- Oregon Hearing Research Center, Department of Otolaryngology/Head & Neck Surgery, Oregon Health & Science University, Portland, OR, 97239, USA.
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40
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Hu BH, Zhang C, Frye MD. Immune cells and non-immune cells with immune function in mammalian cochleae. Hear Res 2018; 362:14-24. [PMID: 29310977 PMCID: PMC5911222 DOI: 10.1016/j.heares.2017.12.009] [Citation(s) in RCA: 58] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/15/2017] [Revised: 11/21/2017] [Accepted: 12/08/2017] [Indexed: 02/07/2023]
Abstract
The cochlea has an immune environment dominated by macrophages under resting conditions. When stressed, circulating monocytes enter the cochlea. These immune mediators, along with cochlear resident cells, organize a complex defense response against pathological challenges. Since the cochlea has minimal exposure to pathogens, most inflammatory conditions in the cochlea are sterile. Although the immune response is initiated for the protection of the cochlea, off-target effects can cause collateral damage to cochlear cells. A better understanding of cochlear immune capacity and regulation would therefore lead to development of new therapeutic treatments. Over the past decade, there have been many advances in our understanding of cochlear immune capacity. In this review, we provide an update and overview of the cellular components of cochlear immune capacity with a focus on macrophages in mammalian cochleae. We describe the composition and distribution of immune cells in the cochlea and suggest that phenotypic and functional characteristics of macrophages have site-specific diversity. We also highlight the response of immune cells to acute and chronic stresses and comment on the potential function of immune cells in cochlear homeostasis and disease development. Finally, we briefly review potential roles for cochlear resident cells in immune activities of the cochlea.
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Affiliation(s)
- Bo Hua Hu
- Center for Hearing and Deafness, University at Buffalo, 137 Cary Hall, 3435 Main Street, Buffalo, NY 14214, USA.
| | - Celia Zhang
- Center for Hearing and Deafness, University at Buffalo, 137 Cary Hall, 3435 Main Street, Buffalo, NY 14214, USA.
| | - Mitchell D Frye
- Center for Hearing and Deafness, University at Buffalo, 137 Cary Hall, 3435 Main Street, Buffalo, NY 14214, USA.
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Zhang W, Zheng J, Meng J, Neng L, Chen X, Qin Z. Macrophage migration inhibitory factor knockdown inhibit viability and induce apoptosis of PVM/Ms. Mol Med Rep 2017; 16:8643-8648. [PMID: 28990052 PMCID: PMC5779918 DOI: 10.3892/mmr.2017.7684] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2016] [Accepted: 07/03/2017] [Indexed: 12/20/2022] Open
Abstract
Previous studies have suggested that macrophage migration inhibitory factor (MIF) serves an important role in hearing function; however, the underlying mechanism remains unclear. In the present study, perivascular‑resident macrophage‑like melanocytes (PVM/Ms) from the stria vascularis of the lateral cochlear wall in young and aged mice were isolated. The mRNA and protein expression levels of MIF were determined using reverse transcription‑quantitative polymerase chain reaction analysis, and western blotting, respectively. MIF expression was knocked down in vitro and in vivo using small interfering RNA. Cell viability was determined using an MTT assay and cell apoptosis was determined using flow cytometry analysis. The hearing ability was assessed through the auditory brain stem response in vivo. The results of the current study demonstrated that the expression of MIF was significantly downregulated in aged mice compared with in young mice. Furthermore, the viability of PVM/Ms in aged mice was significantly decreased and the number of apoptotic PVM/Ms was significantly increased compared with that in young mice. Further studies demonstrated that the MIF knockdown accentuated hearing loss in young mice as compared with the scramble control group. In addition, the MIF knockdown in PVM/Ms significantly inhibited cell viability and lead to a significant increase in the apoptotic cell number as compared with the control group. In summary, these results revealed that the MIF knockdown significantly accentuates hearing loss in young mice in vivo, and significantly inhibits the viability and induces the apoptosis of PVM/Ms in vitro. Thus, the results of the present study may provide a novel potential therapeutic approach and prevention method for presbycusis.
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Affiliation(s)
- Wenjing Zhang
- Department of Otology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan 450000, P.R. China
| | - Jian Zheng
- Department of Otology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan 450000, P.R. China
| | - Juan Meng
- Department of Otology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan 450000, P.R. China
| | - Lingling Neng
- Department of Otology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan 450000, P.R. China
| | - Xiaohua Chen
- Department of Otology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan 450000, P.R. China
| | - Zhaobing Qin
- Department of Otology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan 450000, P.R. China
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42
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Ishiyama G, Lopez IA, Ishiyama P, Vinters HV, Ishiyama A. The blood labyrinthine barrier in the human normal and Meniere's disease macula utricle. Sci Rep 2017; 7:253. [PMID: 28325925 PMCID: PMC5428246 DOI: 10.1038/s41598-017-00330-5] [Citation(s) in RCA: 53] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2016] [Accepted: 02/20/2017] [Indexed: 12/12/2022] Open
Abstract
The ultrastructural organization of the blood labyrinthine barrier (BLB) was investigated in the human vestibular endorgan, the utricular macula, using postmortem specimens from individuals with documented normal auditory and vestibular function and surgical specimens from patients with intractable Meniere’s disease. Transmission electron microscopic analysis of capillaries located in the normal human utricular stroma showed vascular endothelial cells with few pinocytotic vesicles, covered by a smooth and uniform basement membrane surrounded by pericyte processes. Meniere’s disease specimens revealed differential ultrastructural pathological changes in the cellular elements of the microvasculature. With moderate degeneration of the BLB, there were numerous vesicles within the vascular endothelial cells (VECs), with increased numbers at the abluminal face, pericyte process detachment and disruption of the perivascular basement membrane surrounding the VECs. With severe degeneration of the BLB, there was severe vacuolization or frank apparent necrosis of VECs and loss of subcellular organelles. A higher severity of BLB degenerative changes was associated with a higher degree of basement membrane thickening and edematous changes within the vestibular stroma. This study presents the first ultrastructural analysis of the capillaries constituting the BLB in the human vestibular macula utricle from normal and Meniere’s disease.
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Affiliation(s)
- Gail Ishiyama
- Department of Neurology, David Geffen School of Medicine, University of California, Los Angeles, USA.
| | - Ivan A Lopez
- Department of Head and Neck Surgery, David Geffen School of Medicine, University of California, Los Angeles, USA
| | - Paul Ishiyama
- Department of Head and Neck Surgery, David Geffen School of Medicine, University of California, Los Angeles, USA
| | - Harry V Vinters
- Department of Pathology & Laboratory Medicine (Neuropathology), David Geffen School of Medicine, University of California, Los Angeles, USA
| | - Akira Ishiyama
- Department of Head and Neck Surgery, David Geffen School of Medicine, University of California, Los Angeles, USA
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Wang X. The Structure and the Function of the Cochlear Intra-Strial Fluid-Blood Barrier. OTOLARYNGOLOGY (SUNNYVALE, CALIF.) 2017; 7. [PMID: 33282527 PMCID: PMC7713702 DOI: 10.4172/2161-119x.1000308] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Affiliation(s)
- Xiaohan Wang
- Department of Otolaryngology/Head and Neck Surgery, Oregon Hearing Research Center, Oregon Health and Science University, USA
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44
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Pathophysiology of the cochlear intrastrial fluid-blood barrier (review). Hear Res 2016; 338:52-63. [PMID: 26802581 DOI: 10.1016/j.heares.2016.01.010] [Citation(s) in RCA: 138] [Impact Index Per Article: 17.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/15/2015] [Revised: 01/11/2016] [Accepted: 01/14/2016] [Indexed: 12/20/2022]
Abstract
The blood-labyrinth barrier (BLB) in the stria vascularis is a highly specialized capillary network that controls exchanges between blood and the intrastitial space in the cochlea. The barrier shields the inner ear from blood-born toxic substances and selectively passes ions, fluids, and nutrients to the cochlea, playing an essential role in the maintenance of cochlear homeostasis. Anatomically, the BLB is comprised of endothelial cells (ECs) in the strial microvasculature, elaborated tight and adherens junctions, pericytes (PCs), basement membrane (BM), and perivascular resident macrophage-like melanocytes (PVM/Ms), which together form a complex "cochlear-vascular unit" in the stria vascularis. Physical interactions between the ECs, PCs, and PVM/Ms, as well as signaling between the cells, is critical for controlling vascular permeability and providing a proper environment for hearing function. Breakdown of normal interactions between components of the BLB is seen in a wide range of pathological conditions, including genetic defects and conditions engendered by inflammation, loud sound trauma, and ageing. In this review, we will discuss prevailing views of the structure and function of the strial cochlear-vascular unit (also referred to as the "intrastrial fluid-blood barrier"). We will also discuss the disrupted homeostasis seen in a variety of hearing disorders. Therapeutic targeting of the strial barrier may offer opportunities for improvement of hearing health and amelioration of auditory disorders. This article is part of a Special Issue entitled <Annual Reviews 2016>.
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