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Lou J, Wu F, He W, Hu R, Cai Z, Chen G, Zhao W, Zhang Z, Si Y. Hesperidin activates Nrf2 to protect cochlear hair cells from cisplatin-induced damage. Redox Rep 2024; 29:2341470. [PMID: 38629504 PMCID: PMC11025410 DOI: 10.1080/13510002.2024.2341470] [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] [Indexed: 04/19/2024] Open
Abstract
Cisplatin is widely employed in clinical oncology as an anticancer chemotherapy drug in clinical practice and is known for its severe ototoxic side effects. Prior research indicates that the accumulation of reactive oxygen species (ROS) plays a pivotal role in cisplatin's inner ear toxicity. Hesperidin is a flavanone glycoside extracted from citrus fruits that has anti-inflammatory and antioxidant effects. Nonetheless, the specific pharmacological actions of hesperidin in alleviating cisplatin-induced ototoxicity remain elusive. The transcription factor nuclear factor erythroid 2-related factor 2 (Nrf2) is a critical mediator of the cellular oxidative stress response, is influenced by hesperidin. Activation of Nrf2 was shown to have a protective effect against cisplatin-induced ototoxicity. The potential of hesperidin to stimulate Nrf2 in attenuating cisplatin's adverse effects on the inner ear warrants further investigation. This study employs both in vivo and in vitro models of cisplatin ototoxicity to explore this possibility. Our results reveal that hesperidin mitigates cisplatin-induced ototoxicity by activating the Nrf2/NQO1 pathway in sensory hair cells, thereby reducing ROS accumulation, preventing hair cell apoptosis, and alleviating hearing loss.
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Affiliation(s)
- Jintao Lou
- Department of Otolaryngology, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, People’s Republic of China
- Institute of Hearing and Speech-Language Science, Sun Yat-sen University, Guangzhou, People’s Republic of China
- Guangdong Provincial Key Laboratory of Malignant Tumor Epigenetics and Gene Regulation, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, People’s Republic of China
| | - Fan Wu
- Department of Otolaryngology, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, People’s Republic of China
- Institute of Hearing and Speech-Language Science, Sun Yat-sen University, Guangzhou, People’s Republic of China
- Guangdong Provincial Key Laboratory of Malignant Tumor Epigenetics and Gene Regulation, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, People’s Republic of China
| | - Wuhui He
- Department of Otolaryngology, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, People’s Republic of China
- Institute of Hearing and Speech-Language Science, Sun Yat-sen University, Guangzhou, People’s Republic of China
- Guangdong Provincial Key Laboratory of Malignant Tumor Epigenetics and Gene Regulation, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, People’s Republic of China
| | - Rui Hu
- Department of Otolaryngology, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, People’s Republic of China
- Institute of Hearing and Speech-Language Science, Sun Yat-sen University, Guangzhou, People’s Republic of China
- Guangdong Provincial Key Laboratory of Malignant Tumor Epigenetics and Gene Regulation, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, People’s Republic of China
| | - Ziyi Cai
- Department of Otolaryngology, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, People’s Republic of China
- Institute of Hearing and Speech-Language Science, Sun Yat-sen University, Guangzhou, People’s Republic of China
- Guangdong Provincial Key Laboratory of Malignant Tumor Epigenetics and Gene Regulation, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, People’s Republic of China
| | - Guisheng Chen
- Department of Otolaryngology, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, People’s Republic of China
- Institute of Hearing and Speech-Language Science, Sun Yat-sen University, Guangzhou, People’s Republic of China
- Guangdong Provincial Key Laboratory of Malignant Tumor Epigenetics and Gene Regulation, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, People’s Republic of China
| | - Wenji Zhao
- Department of Otolaryngology, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, People’s Republic of China
- Institute of Hearing and Speech-Language Science, Sun Yat-sen University, Guangzhou, People’s Republic of China
- Guangdong Provincial Key Laboratory of Malignant Tumor Epigenetics and Gene Regulation, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, People’s Republic of China
| | - Zhigang Zhang
- Department of Otolaryngology, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, People’s Republic of China
- Institute of Hearing and Speech-Language Science, Sun Yat-sen University, Guangzhou, People’s Republic of China
- Guangdong Provincial Key Laboratory of Malignant Tumor Epigenetics and Gene Regulation, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, People’s Republic of China
| | - Yu Si
- Department of Otolaryngology, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, People’s Republic of China
- Institute of Hearing and Speech-Language Science, Sun Yat-sen University, Guangzhou, People’s Republic of China
- Guangdong Provincial Key Laboratory of Malignant Tumor Epigenetics and Gene Regulation, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, People’s Republic of China
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Wu F, Hu R, Huang X, Lou J, Cai Z, Chen G, Zhao W, Xiong H, Sha SH, Zheng Y. CFTR potentiator ivacaftor protects against noise-induced hair cell loss by increasing Nrf2 and reducing oxidative stress. Biomed Pharmacother 2023; 166:115399. [PMID: 37657258 PMCID: PMC10528730 DOI: 10.1016/j.biopha.2023.115399] [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: 06/12/2023] [Revised: 08/23/2023] [Accepted: 08/26/2023] [Indexed: 09/03/2023] Open
Abstract
Over-production of reactive oxygen species (ROS) in the inner ear can be triggered by a variety of pathological events identified in animal models after traumatic noise exposure. Our previous research found that inhibition of the AMP-activated protein kinase alpha subunit (AMPKα) protects against noise-induced cochlear hair cell loss and hearing loss by reducing ROS accumulation. However, the molecular pathway through which AMPKα exerts its antioxidative effect is still unclear. In this study, we have investigated a potential target of AMPKα and ROS, cystic fibrosis transmembrane conductance regulator (CFTR), and the protective effect against noise-induced hair cell loss of an FDA-approved CFTR potentiator, ivacaftor, in FVB/NJ mice, mouse explant cultures, and HEI-OC1 cells. We found that noise exposure increases phosphorylation of CFTR at serine 737 (p-CFTR, S737), which reduces wildtype CFTR function, resulting in oxidative stress in cochlear sensory hair cells. Pretreatment with a single dose of ivacaftor maintains CFTR function by preventing noise-increased p-CFTR (S737). Furthermore, ivacaftor treatment increases nuclear factor E2-related factor 2 (Nrf2) expression, diminishes ROS formation, and attenuates noise-induced hair cell loss and hearing loss. Additionally, inhibition of noise-induced AMPKα activation by compound C also diminishes p-CFTR (S737) expression. In line with these in-vivo results, administration of hydrogen peroxide to cochlear explants or HEI-OC1 cells increases p-CFTR (S737) expression and induces sensory hair cell or HEI-OC1 cell damage, while application of ivacaftor halts these effects. Although ivacaftor increases Nrf2 expression and reduces ROS accumulation, cotreatment with ML385, an Nrf2 inhibitor, abolishes the protective effects of ivacaftor against hydrogen-peroxide-induced HEI-OC1 cell death. Our results indicate that noise-induced sensory hair cell damage is associated with p-CFTR. Ivacaftor has potential for treatment of noise-induced hearing loss by maintaining CFTR function and increasing Nrf2 expression for support of redox homeostasis in sensory hair cells.
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Affiliation(s)
- Fan Wu
- Department of Otolaryngology, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, Guangdong, China; Guangdong Provincial Key Laboratory of Malignant Tumor Epigenetics and Gene Regulation, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, Guangdong, China; Institute of Hearing and Speech-Language Science, Sun Yat-sen University, Guangzhou 510120, China; Department of Pathology and Laboratory Medicine, The Medical University of South Carolina, Charleston, SC, USA
| | - Rui Hu
- Department of Otolaryngology, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, Guangdong, China; Shenshan Medical Center, Memorial Hospital of Sun Yat-sen University, Shanwei, Guangdong, China; Institute of Hearing and Speech-Language Science, Sun Yat-sen University, Guangzhou 510120, China
| | - Xueping Huang
- Department of Otolaryngology, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, Guangdong, China; Guangdong Provincial Key Laboratory of Malignant Tumor Epigenetics and Gene Regulation, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, Guangdong, China; Institute of Hearing and Speech-Language Science, Sun Yat-sen University, Guangzhou 510120, China
| | - Jintao Lou
- Department of Otolaryngology, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, Guangdong, China; Guangdong Provincial Key Laboratory of Malignant Tumor Epigenetics and Gene Regulation, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, Guangdong, China; Institute of Hearing and Speech-Language Science, Sun Yat-sen University, Guangzhou 510120, China
| | - Ziyi Cai
- Department of Otolaryngology, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, Guangdong, China; Guangdong Provincial Key Laboratory of Malignant Tumor Epigenetics and Gene Regulation, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, Guangdong, China; Institute of Hearing and Speech-Language Science, Sun Yat-sen University, Guangzhou 510120, China
| | - Guisheng Chen
- Department of Otolaryngology, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, Guangdong, China; Guangdong Provincial Key Laboratory of Malignant Tumor Epigenetics and Gene Regulation, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, Guangdong, China; Institute of Hearing and Speech-Language Science, Sun Yat-sen University, Guangzhou 510120, China
| | - Wenji Zhao
- Department of Otolaryngology, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, Guangdong, China; Guangdong Provincial Key Laboratory of Malignant Tumor Epigenetics and Gene Regulation, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, Guangdong, China; Institute of Hearing and Speech-Language Science, Sun Yat-sen University, Guangzhou 510120, China
| | - Hao Xiong
- Department of Otolaryngology, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, Guangdong, China; Guangdong Provincial Key Laboratory of Malignant Tumor Epigenetics and Gene Regulation, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, Guangdong, China; Institute of Hearing and Speech-Language Science, Sun Yat-sen University, Guangzhou 510120, China
| | - Su-Hua Sha
- Department of Pathology and Laboratory Medicine, The Medical University of South Carolina, Charleston, SC, USA.
| | - Yiqing Zheng
- Department of Otolaryngology, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, Guangdong, China; Shenshan Medical Center, Memorial Hospital of Sun Yat-sen University, Shanwei, Guangdong, China; Guangdong Provincial Key Laboratory of Malignant Tumor Epigenetics and Gene Regulation, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, Guangdong, China; Institute of Hearing and Speech-Language Science, Sun Yat-sen University, Guangzhou 510120, China.
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Wang X, Zhou Z, Yu C, He K, Sun L, Kou Y, Zhang M, Zhang Z, Luo P, Wen L, Chen G. A prestin-targeting peptide-guided drug delivery system rearranging concentration gradient in the inner ear: An improved strategy against hearing loss. Eur J Pharm Sci 2023; 187:106490. [PMID: 37295658 DOI: 10.1016/j.ejps.2023.106490] [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: 03/30/2023] [Revised: 05/23/2023] [Accepted: 06/06/2023] [Indexed: 06/12/2023]
Abstract
Hearing loss is mainly due to outer hair cell (OHC) damage in three cochlear turns. Local administration via the round window membrane (RWM) has considerable otological clinical potential in bypassing the blood-labyrinth barrier. However, insufficient drug distribution in the apical and middle cochlear turns results in unsatisfactory efficacy. We functionalized poly (lactic-co-glycolic acid) nanoparticles (PLGA NPs) with targeting peptide A665, which specifically bound to prestin, a protein uniquely expressed in OHCs. The modification facilitated the cellular uptake and RWM permeability of NPs. Notably, the guide of A665 towards OHCs enabled more NPs perfusion in the apical and middle cochlear turns without decreasing accumulation in the basal cochlear turn. Subsequently, curcumin (CUR), an appealing anti-ototoxic drug, was encapsulated in NPs. In aminoglycoside-treated guinea pigs with the worst hearing level, CUR/A665-PLGA NPs, with superior performance to CUR/PLGA NPs, almost completely preserved the OHCs in three cochlear turns. The lack of increased low-frequencies hearing thresholds further confirmed that the delivery system with prestin affinity mediated cochlear distribution rearrangement. Good inner ear biocompatibility and little or no embryonic zebrafish toxicity were observed throughout the treatment. Overall, A665-PLGA NPs act as desirable tools with sufficient inner ear delivery for improved efficacy against severe hearing loss.
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Affiliation(s)
- Xinrui Wang
- Guangdong Provincial Key Laboratory of Advanced Drug Delivery & Guangdong Provincial Engineering Center of Topical Precise Drug Delivery System & Class III Laboratory of Modern Chinese Medicine Preparation & Key Laboratory of Modern Chinese Medicine of Education Department of Guangdong Province, Center for Drug Research and Development, Guangdong Pharmaceutical University, Guangzhou 510006, China
| | - Zeming Zhou
- Guangdong Provincial Key Laboratory of Advanced Drug Delivery & Guangdong Provincial Engineering Center of Topical Precise Drug Delivery System & Class III Laboratory of Modern Chinese Medicine Preparation & Key Laboratory of Modern Chinese Medicine of Education Department of Guangdong Province, Center for Drug Research and Development, Guangdong Pharmaceutical University, Guangzhou 510006, China
| | - Chong Yu
- Guangdong Provincial Key Laboratory of Advanced Drug Delivery & Guangdong Provincial Engineering Center of Topical Precise Drug Delivery System & Class III Laboratory of Modern Chinese Medicine Preparation & Key Laboratory of Modern Chinese Medicine of Education Department of Guangdong Province, Center for Drug Research and Development, Guangdong Pharmaceutical University, Guangzhou 510006, China
| | - Kerui He
- Guangdong Provincial Key Laboratory of Advanced Drug Delivery & Guangdong Provincial Engineering Center of Topical Precise Drug Delivery System & Class III Laboratory of Modern Chinese Medicine Preparation & Key Laboratory of Modern Chinese Medicine of Education Department of Guangdong Province, Center for Drug Research and Development, Guangdong Pharmaceutical University, Guangzhou 510006, China
| | - Lifang Sun
- Guangdong Provincial Key Laboratory of Advanced Drug Delivery & Guangdong Provincial Engineering Center of Topical Precise Drug Delivery System & Class III Laboratory of Modern Chinese Medicine Preparation & Key Laboratory of Modern Chinese Medicine of Education Department of Guangdong Province, Center for Drug Research and Development, Guangdong Pharmaceutical University, Guangzhou 510006, China
| | - Yuwei Kou
- Guangdong Provincial Key Laboratory of Advanced Drug Delivery & Guangdong Provincial Engineering Center of Topical Precise Drug Delivery System & Class III Laboratory of Modern Chinese Medicine Preparation & Key Laboratory of Modern Chinese Medicine of Education Department of Guangdong Province, Center for Drug Research and Development, Guangdong Pharmaceutical University, Guangzhou 510006, China
| | - Ming Zhang
- Guangdong Sunho Pharmaceutical Co. Ltd, Zhongshan 528437, China
| | - Zhifeng Zhang
- State Key Laboratory for Quality Research in Chinese Medicine, Macau University of Science and Technology, Macau 000853, China
| | - Pei Luo
- State Key Laboratory for Quality Research in Chinese Medicine, Macau University of Science and Technology, Macau 000853, China
| | - Lu Wen
- School of Pharmacy, Guangdong Pharmaceutical University, Guangzhou 510006, China.
| | - Gang Chen
- Guangdong Provincial Key Laboratory of Advanced Drug Delivery & Guangdong Provincial Engineering Center of Topical Precise Drug Delivery System & Class III Laboratory of Modern Chinese Medicine Preparation & Key Laboratory of Modern Chinese Medicine of Education Department of Guangdong Province, Center for Drug Research and Development, Guangdong Pharmaceutical University, Guangzhou 510006, China.
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Wijesinghe P, Sastry A, Hui E, Cogan TA, Zheng B, Ho G, Kakal J, Nunez DA. Adult porcine (Sus scrofa) derived inner ear cells: Characteristics in in-vitro cultures. Anat Rec (Hoboken) 2023. [PMID: 36598271 DOI: 10.1002/ar.25149] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2022] [Revised: 11/21/2022] [Accepted: 12/10/2022] [Indexed: 01/05/2023]
Abstract
There is a need for an animal model that closely parallels human cochlea gestational development. This study aims to document porcine inner ear anatomy, and in vitro porcine derived inner ear cell culture characteristics. Twenty-four temporal bone were harvested from 12 adult pigs (Sus scrofa). Six were formalin fixed and their maximal diameters were measured. The cochlea duct length was determined by the insertion length of a Nucleus 22 cochlear implant in two bones. Four formalin fixed bones were sectioned for histology. Cochlear and vestibular tissues were harvested from non-fixed bones, cultured and characterized at different passages (P). Gene and protein expression of multipotent stem/progenitor (Nestin and Sox2), inner ear hair (Myosin VIIa, Prestin) and supporting (Cytokeratin 18 and Vimentin) cell markers were determined. The porcine cochlea was a 3.5 turn spiral. There was a separate vestibular compartment. The cochlear mean maximal diameter and height was 7.99 and 3.77 mm, respectively. Sphere forming cells were identified on phase-contrast microscopy. The relative mRNA expression levels of KRT18, MYO7A and SLC26A5 were significantly positively correlated in cochlear cultures; and MYO7A and SLC26A5; SOX2 and KRT18; NES and SLC26A5 genes were positively correlated in vestibular cultures (p = .037, Spearman correlation [τ] = .900). Inner ear sensory and stem cell characteristics persist in passaged porcine inner ear cells. Further work is required to establish the usefulness of porcine inner ear cell cultures to the study of human inner ear disorders.
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Affiliation(s)
- Printha Wijesinghe
- Division of Otolaryngology, Department of Surgery, University of British Columbia, Vancouver, British Columbia, Canada
- Vancouver Coastal Health Research Institute, Vancouver, British Columbia, Canada
| | - Anand Sastry
- Bristol Veterinary School, University of Bristol, Bristol, UK
| | - Elizabeth Hui
- Division of Otolaryngology, Department of Surgery, University of British Columbia, Vancouver, British Columbia, Canada
- Vancouver Coastal Health Research Institute, Vancouver, British Columbia, Canada
| | - Tristan A Cogan
- Bristol Veterinary School, University of Bristol, Bristol, UK
| | - Boyuan Zheng
- Division of Otolaryngology, Department of Surgery, University of British Columbia, Vancouver, British Columbia, Canada
- Vancouver Coastal Health Research Institute, Vancouver, British Columbia, Canada
| | - Germain Ho
- Division of Otolaryngology, Department of Surgery, University of British Columbia, Vancouver, British Columbia, Canada
- Vancouver Coastal Health Research Institute, Vancouver, British Columbia, Canada
| | - Juzer Kakal
- Division of Otolaryngology, Department of Surgery, University of British Columbia, Vancouver, British Columbia, Canada
- Vancouver Coastal Health Research Institute, Vancouver, British Columbia, Canada
| | - Desmond A Nunez
- Division of Otolaryngology, Department of Surgery, University of British Columbia, Vancouver, British Columbia, Canada
- Vancouver Coastal Health Research Institute, Vancouver, British Columbia, Canada
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Xu X, Liu Y, Luan J, Liu R, Wang Y, Liu Y, Xu A, Zhou B, Han F, Shang W. Effect of downregulated citrate synthase on oxidative phosphorylation signaling pathway in HEI-OC1 cells. Proteome Sci 2022; 20:14. [PMID: 36071491 PMCID: PMC9450364 DOI: 10.1186/s12953-022-00196-0] [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: 06/26/2022] [Accepted: 08/27/2022] [Indexed: 11/13/2022] Open
Abstract
Background Citrate Synthase (Cs) gene mutation (locus ahL4) has been found to play an important role in progressive hearing loss of A/J mice. HEI-OC1 cells have been widely used as an in vitro system to study cellular and molecular mechanisms related to hearing lose. We previously reported the increased apoptosis and the accumulation of reactive oxygen species in shRNACs-1429 cells, a Cs low-expressed cell model from HEI-OCI. The details of the mechanism of ROS production and apoptosis mediated by the abnormal expression of Cs needed to research furtherly. Methods iTRAQ proteomics was utilized to detect the differentially expressed proteins (DEPs) caused by low expression of Cs. The GO and KEGG pathways analysis were performed for annotation of the differentially expressed proteins. Protein–protein interaction network was constructed by STRING online database. Immunoblotting was utilized to confirm the protein levels of the the differentially expressed proteins. Results The differentially expressed proteins were significantly enriched in various signaling pathways mainly related to mitochondrial dysfunction diseases including Parkinson’s disease, Alzheimer’s disease, Huntington’s disease, et al. Most noteworthy, the oxidative phosphorylation pathway was most significantly suppressed in the shRNACs-1429 cells,, in which a total of 10 differentially expressed proteins were enriched and were all downregulated by the abnormal expression of Cs. The downregulations of Ndufb5, Ndufv1 and Uqcrb were confirmed by immunoblotting. Meanwhile, the ATP levels of shRNACs-1429 cells were also reduced. Conclusions These results suggest that low level expression of Cs induces the inhibition of oxidative phosphorylation pathway, which is responsible for the high level production of reactive oxygen species and low level of ATP, leading to the apoptosis of cochlear cells. This study may provide new theories for understanding and therapy of progressive hearing loss. Supplementary Information The online version contains supplementary material available at 10.1186/s12953-022-00196-0.
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Affiliation(s)
- Xiaowen Xu
- Key Laboratory for Genetic Hearing Disorders in Shandong, Binzhou Medical University, 346 Guanhai Road, Yantai, 264003, Shandong, People's Republic of China.,Department of Otolaryngology, Yantai Affiliated Hospital of Binzhou Medical University, 717 Jinbu Road of Muping District, Yantai, 264100, Shandong, People's Republic of China
| | - Yue Liu
- Key Laboratory for Genetic Hearing Disorders in Shandong, Binzhou Medical University, 346 Guanhai Road, Yantai, 264003, Shandong, People's Republic of China.,Department of anesthesiology, Yantai Affiliated Hospital of Binzhou Medical University, 717 Jinbu Road of Muping District, Yantai, 264100, Shandong, People's Republic of China
| | - Jun Luan
- Key Laboratory for Genetic Hearing Disorders in Shandong, Binzhou Medical University, 346 Guanhai Road, Yantai, 264003, Shandong, People's Republic of China.,Department of Biochemistry and Molecular Biology, Binzhou Medical University, 346 Guanhai Road, Yantai, 264003, Shandong, People's Republic of China
| | - Rongrong Liu
- Key Laboratory for Genetic Hearing Disorders in Shandong, Binzhou Medical University, 346 Guanhai Road, Yantai, 264003, Shandong, People's Republic of China
| | - Yan Wang
- Key Laboratory for Genetic Hearing Disorders in Shandong, Binzhou Medical University, 346 Guanhai Road, Yantai, 264003, Shandong, People's Republic of China.,Department of Biochemistry and Molecular Biology, Binzhou Medical University, 346 Guanhai Road, Yantai, 264003, Shandong, People's Republic of China
| | - Yingying Liu
- Key Laboratory for Genetic Hearing Disorders in Shandong, Binzhou Medical University, 346 Guanhai Road, Yantai, 264003, Shandong, People's Republic of China.,Department of Biochemistry and Molecular Biology, Binzhou Medical University, 346 Guanhai Road, Yantai, 264003, Shandong, People's Republic of China
| | - Ang Xu
- Key Laboratory for Genetic Hearing Disorders in Shandong, Binzhou Medical University, 346 Guanhai Road, Yantai, 264003, Shandong, People's Republic of China.,Department of Otolaryngology, Yantai Affiliated Hospital of Binzhou Medical University, 717 Jinbu Road of Muping District, Yantai, 264100, Shandong, People's Republic of China
| | - Bingxin Zhou
- Key Laboratory for Genetic Hearing Disorders in Shandong, Binzhou Medical University, 346 Guanhai Road, Yantai, 264003, Shandong, People's Republic of China.,Department of Biochemistry and Molecular Biology, Binzhou Medical University, 346 Guanhai Road, Yantai, 264003, Shandong, People's Republic of China
| | - Fengchan Han
- Key Laboratory for Genetic Hearing Disorders in Shandong, Binzhou Medical University, 346 Guanhai Road, Yantai, 264003, Shandong, People's Republic of China. .,Department of Biochemistry and Molecular Biology, Binzhou Medical University, 346 Guanhai Road, Yantai, 264003, Shandong, People's Republic of China.
| | - Wenjing Shang
- Key Laboratory for Genetic Hearing Disorders in Shandong, Binzhou Medical University, 346 Guanhai Road, Yantai, 264003, Shandong, People's Republic of China. .,Department of Biochemistry and Molecular Biology, Binzhou Medical University, 346 Guanhai Road, Yantai, 264003, Shandong, People's Republic of China.
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Identification of Target Proteins Involved in Cochlear Hair Cell Progenitor Cytotoxicity following Gentamicin Exposure. J Clin Med 2022; 11:jcm11144072. [PMID: 35887836 PMCID: PMC9319054 DOI: 10.3390/jcm11144072] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2022] [Revised: 06/30/2022] [Accepted: 07/06/2022] [Indexed: 02/04/2023] Open
Abstract
Given the non-labile, terminal differentiation of inner-ear sensory cells, preserving their function is critical since sensory cell damage results in irreversible hearing loss. Gentamicin-induced cytotoxicity is one of the major causes of sensory cell damage and consequent sensorineural hearing loss. However, the precise molecular mechanisms and target proteins involved in ototoxicity are still unknown. The objective of the present study was to identify target proteins involved in gentamicin-induced cytotoxicity to better characterize the molecular pathways involved in sensory cell damage following ototoxic drug administration using House Ear Institute-Organ of Corti 1 (HEI-OC1) cells and high-performance liquid chromatography coupled with tandem mass spectrometry (HPLC-MS/MS). We identified several unique proteins involved in gentamicin-induced cytotoxicity, expression of which were further confirmed using confocal microscopy. Further investigation of these pathways can inform the design and discovery of novel treatment modalities to prevent sensory cell damage and preserve their function.
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MicroRNA Signature and Cellular Characterization of Undifferentiated and Differentiated House Ear Institute-Organ of Corti 1 (HEI-OC1) Cells. J Assoc Res Otolaryngol 2022; 23:467-489. [PMID: 35546217 PMCID: PMC9094604 DOI: 10.1007/s10162-022-00850-6] [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: 08/13/2020] [Accepted: 04/20/2022] [Indexed: 11/29/2022] Open
Abstract
MicroRNAs (miRNAs) regulate gene expressions and control a wide variety of cellular functions. House Ear Institute-Organ of Corti 1 (HEI-OC1) cells are widely used to screen ototoxic drugs and to investigate cellular and genetic alterations in response to various conditions. HEI-OC1 cells are almost exclusively studied under permissive conditions that promote cell replication at the expense of differentiation. Many researchers suggest that permissive culture condition findings are relevant to understanding human hearing disorders. The mature human cochlea however consists of differentiated cells and lacks proliferative capacity. This study therefore aimed to compare the miRNA profiles and cellular characteristics of HEI-OC1 cells cultured under permissive (P-HEI-OC1) and non-permissive (NP-HEI-OC1) conditions. A significant increase in the level of expression of tubulin β1 class VI (Tubb1), e-cadherin (Cdh1), espin (Espn), and SRY (sex determining region Y)-box2 (Sox2) mRNAs was identified in non-permissive cells compared with permissive cells (P < 0.05, Kruskal–Wallis H test, 2-sided). miR-200 family, miR-34b/c, and miR-449a/b functionally related cluster miRNAs, rodent-specific maternally imprinted gene Sfmbt2 intron 10th cluster miRNAs (-466a/ -467a), and miR-17 family were significantly (P < 0.05, Welch’s t-test, 2-tailed) differentially expressed in non-permissive cells when compared with permissive cells. Putative target genes were significantly predominantly enriched in mitogen-activated protein kinase (MAPK), epidermal growth factor family of receptor tyrosine kinases (ErbB), and Ras signaling pathways in non-permissive cells compared with permissive cells. This distinct miRNA signature of differentiated HEI-OC1 cells could help in understanding miRNA-mediated cellular responses in the adult cochlea.
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Niu P, Sun Y, Wang S, Li G, Tang X, Sun J, Pan C, Sun J. Puerarin alleviates the ototoxicity of gentamicin by inhibiting the mitochondria‑dependent apoptosis pathway. Mol Med Rep 2021; 24:851. [PMID: 34651662 PMCID: PMC8532108 DOI: 10.3892/mmr.2021.12491] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2021] [Accepted: 09/22/2021] [Indexed: 11/24/2022] Open
Abstract
Gentamicin (GM) is a commonly used antibiotic, and ototoxicity is one of its side effects. Puerarin (PU) is an isoflavone in kudzu roots that exerts a number of pharmacological effects, including antioxidative and free radical scavenging effects. The present study investigated whether PU could protect against GM-induced ototoxicity in C57BL/6J mice and House Ear Institute-Organ of Corti 1 (HEI-OC1) cells. C57BL/6J mice and HEI-OC1 cells were used to establish models of GM-induced ototoxicity in this study. Auditory brainstem responses were measured to assess hearing thresholds, and microscopy was used to observe the morphology of cochlear hair cells after fluorescent staining. Cell viability was examined with Cell Counting Kit-8 assays. To evaluate cell apoptosis and reactive oxygen species (ROS) production, TUNEL assays, reverse transcription-quantitative PCR, DCFH-DA staining, JC-1 staining and western blotting were performed. PU protected against GM-induced hearing damage in C57BL/6J mice. PU ameliorated the morphological changes of mouse cochlear hair cells and reduced the apoptosis rate of HEI-OC1 cells after GM-mediated damage. GM-induced ototoxicity may be closely related to the upregulation of p53 expression and the activation of endogenous mitochondrial apoptosis pathways, and PU could protect cochlear hair cells from GM-mediated damage by reducing the production of ROS and inhibiting the mitochondria-dependent apoptosis pathway.
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Affiliation(s)
- Ping Niu
- Department of Otolaryngology‑Head and Neck Surgery, Anhui Provincial Hospital, Cheeloo College of Medicine, Shandong University, Jinan, Shandong 250012, P.R. China
| | - Yuxuan Sun
- Department of Otolaryngology‑Head and Neck Surgery, Anhui Provincial Hospital, Hefei, Anhui 230001, P.R. China
| | - Shiyi Wang
- Department of Otolaryngology‑Head and Neck Surgery, Affiliated Hospital of Yangzhou University, Yangzhou, Jiangsu 225001, P.R. China
| | - Guang Li
- Department of Otolaryngology‑Head and Neck Surgery, Affiliated Hospital of Yangzhou University, Yangzhou, Jiangsu 225001, P.R. China
| | - Xiaomin Tang
- Department of Otolaryngology‑Head and Neck Surgery, Anhui Provincial Hospital, Hefei, Anhui 230001, P.R. China
| | - Jiaqiang Sun
- Department of Otolaryngology‑Head and Neck Surgery, Anhui Provincial Hospital, Hefei, Anhui 230001, P.R. China
| | - Chunchen Pan
- Department of Otolaryngology‑Head and Neck Surgery, Anhui Provincial Hospital, Hefei, Anhui 230001, P.R. China
| | - Jingwu Sun
- Department of Otolaryngology‑Head and Neck Surgery, Anhui Provincial Hospital, Hefei, Anhui 230001, P.R. China
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9
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Han H, Dong Y, Ma X. Dihydromyricetin Protects Against Gentamicin-Induced Ototoxicity via PGC-1α/SIRT3 Signaling in vitro. Front Cell Dev Biol 2020; 8:702. [PMID: 32850822 PMCID: PMC7399350 DOI: 10.3389/fcell.2020.00702] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2020] [Accepted: 07/10/2020] [Indexed: 12/20/2022] Open
Abstract
Aminoglycoside-induced ototoxicity can have a major impact on patients’ quality of life and social development problems. Oxidative stress affects normal physiologic functions and has been implicated in aminoglycoside-induced inner ear injury. Excessive accumulation of reactive oxygen species (ROS) damages DNA, lipids, and proteins in cells and induces their apoptosis. Dihydromyricetin (DHM) is a natural flavonol with a wide range of health benefits including anti-inflammatory, antitumor, and antioxidant effects; however, its effects and mechanism of action in auditory hair cells are not well understood. The present study investigated the antioxidant mechanism and anti-ototoxic potential of DHM using House Ear Institute-Organ of Corti (HEI-OC)1 auditory cells and cochlear explant cultures prepared from Kunming mice. We used gentamicin to establish aminoglycoside-induced ototoxicity models. Histological and physiological analyses were carried out to determine DHM’s pharmacological effects on gentamicin-induced ototoxicity. Results showed DHM contributes to protecting cells from apoptotic cell death by inhibiting ROS accumulation. Western blotting and quantitative RT-PCR analyses revealed that DHM exerted its otoprotective effects by up-regulating levels of peroxisome proliferator activated receptor γ-coactivator (PGC)-1α and Sirtuin (SIRT)3. And the role of PGC-1α and SIRT3 in the protective effects of DHM was evaluated by pharmacologic inhibition of these factors using SR-18292 and 3-(1H-1,2,3-triazol-4-yl) pyridine, respectively, which indicated DHM’s protective effect was dependent on activation of the PGC-1α/SIRT3 signaling. Our study is the first report to identify DHM as a potential otoprotective drug and provides a basis for the prevention and treatment of hearing loss caused by aminoglycoside antibiotic-induced oxidative damage to auditory hair cells.
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Affiliation(s)
- Hezhou Han
- Department of Otolaryngology Head and Neck Surgery, Shengjing Hospital of China Medical University, Shenyang, China
| | - Yaodong Dong
- Department of Otolaryngology Head and Neck Surgery, Shengjing Hospital of China Medical University, Shenyang, China
| | - Xiulan Ma
- Department of Otolaryngology Head and Neck Surgery, Shengjing Hospital of China Medical University, Shenyang, China
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10
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Beach R, Abitbol JM, Allman BL, Esseltine JL, Shao Q, Laird DW. GJB2 Mutations Linked to Hearing Loss Exhibit Differential Trafficking and Functional Defects as Revealed in Cochlear-Relevant Cells. Front Cell Dev Biol 2020; 8:215. [PMID: 32300592 PMCID: PMC7142214 DOI: 10.3389/fcell.2020.00215] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2019] [Accepted: 03/12/2020] [Indexed: 11/13/2022] Open
Abstract
GJB2 gene (that encodes Cx26) mutations are causal of hearing loss highlighting the importance of Cx26-based channel signaling amongst the supporting cells in the organ of Corti. While the majority of these GJB2 mutations are inherited in an autosomal recessive manner, others are inherited in an autosomal dominant manner and lead to syndromic hearing loss as well as skin diseases. To assess if common or divergent mechanisms are at the root of GJB2-linked hearing loss, we expressed several mutants in cochlear-relevant HEI-OC1 cells derived from the developing organ of Corti. Since supporting cells of the mature mammalian organ of Corti have negligible Cx43, but HEI-OC1 cells are rich in Cx43, we first used CRISPR-Cas9 to ablate endogenous Cx43, thus establishing a connexin-deficient platform for controlled reintroduction of hearing-relevant connexins and Cx26 mutants. We found three distinct outcomes and cellular phenotypes when hearing loss-linked Cx26 mutants were expressed in cochlear-relevant cells. The dominant syndromic Cx26 mutant N54K had trafficking defects and did not fully prevent wild-type Cx26 gap junction plaque formation but surprisingly formed gap junctions when co-expressed with Cx30. In contrast, the dominant syndromic S183F mutant formed gap junctions incapable of transferring dye and, as expected, co-localized in the same gap junctions as wild-type Cx26 and Cx30, but also gained the capacity to intermix with Cx43 within gap junctions. Both recessive non-syndromic Cx26 mutants (R32H and R184P) were retained in intracellular vesicles including early endosomes and did not co-localize with Cx30. As might be predicted, none of the Cx26 mutants prevented Cx43 gap junction plaque formation in Cx43-rich HEI-OC1 cells while Cx43-ablation had little effect on the expression of reference genes linked to auditory cell differentiation. We conclude from our studies in cochlear-relevant cells that the selected Cx26 mutants likely evoke hearing loss via three unique connexin defects that are independent of Cx43 status.
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Affiliation(s)
- Rianne Beach
- Department of Anatomy and Cell Biology, Schulich School of Medicine & Dentistry, University of Western Ontario, London, ON, Canada
| | - Julia M. Abitbol
- Department of Anatomy and Cell Biology, Schulich School of Medicine & Dentistry, University of Western Ontario, London, ON, Canada
| | - Brian L. Allman
- Department of Anatomy and Cell Biology, Schulich School of Medicine & Dentistry, University of Western Ontario, London, ON, Canada
| | - Jessica L. Esseltine
- Division of BioMedical Sciences, Faculty of Medicine, Memorial University of Newfoundland, St. John’s, NL, Canada
| | - Qing Shao
- Department of Anatomy and Cell Biology, Schulich School of Medicine & Dentistry, University of Western Ontario, London, ON, Canada
| | - Dale W. Laird
- Department of Anatomy and Cell Biology, Schulich School of Medicine & Dentistry, University of Western Ontario, London, ON, Canada
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11
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Luo X, Xia Y, Li XD, Wang JY. The effect of AP-2δ on transcription of the Prestin gene in HEI-OC1 cells upon oxidative stress. Cell Mol Biol Lett 2019; 24:45. [PMID: 31297132 PMCID: PMC6595603 DOI: 10.1186/s11658-019-0170-0] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2019] [Accepted: 06/07/2019] [Indexed: 12/18/2022] Open
Abstract
Background The study aimed to investigate the effect of oxidative stress on Prestin expression, and explore the transcription factors (TFs) that are involved in regulating the expression of Prestin in House Ear Institute-Organ of Corti 1 (HEI-OC1) cells upon oxidative stress. Methods Quantitative real-time polymerase chain reaction (qRT-PCR) and Western blot were used to detect the expression level of Prestin. Reverse chromatin immunoprecipitation (reverse ChIP) assay was performed to identify proteins that could bind to the Prestin gene. Small interfering RNA (siRNA) and chromatin immunoprecipitation (ChIP) experiments were used to further verify the results. HEI-OC1 cells were incubated with four different concentrations of tert-butyl hydroperoxide (t-BHP) for 24 h or 48 h to construct the oxidative stress model. Results Oxidative stress induced Prestin increase at the mRNA level but with a concomitant decrease at the protein level. TF activating enhancer binding protein-2δ (AP-2δ) screened by reverse ChIP assay was demonstrated to bind to transcriptional start site 1441 of the Prestin promoter region and negatively regulate the expression of Prestin by siRNA and ChIP experiments. Furthermore, AP-2δ was down-regulated under oxidative stress. Conclusions In conclusion, oxidative stress inhibits the expression of Prestin protein, and the transcription mechanism is triggered to compensate for the loss of Prestin protein. AP-2δ is one of the important TFs that suppresses transcription of the Prestin gene, and AP-2δ suppression further boosted Prestin mRNA activation under oxidative stress. Electronic supplementary material The online version of this article (10.1186/s11658-019-0170-0) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Xuan Luo
- 1Department of Labor Health and Environmental Hygiene, School of Public Health, Guangdong Pharmaceutical University, Guangzhou, 510310 China
| | - Yun Xia
- 2Department of Labor Health and Environmental Hygiene, School of Public Health, Guangdong Pharmaceutical University, Guangzhou, 510310 China
| | - Xu-Dong Li
- Key Laboratory, Occupational Disease Prevention and Control of Hospital of Guangdong Province, Guangzhou, 510300 China
| | - Jun-Yi Wang
- 1Department of Labor Health and Environmental Hygiene, School of Public Health, Guangdong Pharmaceutical University, Guangzhou, 510310 China
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12
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Ogier JM, Burt RA, Drury HR, Lim R, Nayagam BA. Organotypic Culture of Neonatal Murine Inner Ear Explants. Front Cell Neurosci 2019; 13:170. [PMID: 31130846 PMCID: PMC6509234 DOI: 10.3389/fncel.2019.00170] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2018] [Accepted: 04/11/2019] [Indexed: 01/08/2023] Open
Abstract
The inner ear is a complex organ containing highly specialised cell types and structures that are critical for sensing sound and movement. In vivo, the inner ear is difficult to study due to the osseous nature of the otic capsule and its encapsulation within an intricate bony labyrinth. As such, mammalian inner ear explants are an invaluable tool for the study and manipulation of the complex intercellular connections, structures, and cell types within this specialised organ. The greatest strength of this technique is that the complete organ of Corti, or peripheral vestibular organs including hair cells, supporting cells and accompanying neurons, is maintained in its in situ form. The greatest weakness of in vitro hair cell preparations is the short time frame in which the explanted tissue remains viable. Yet, cochlear explants have proven to be an excellent experimental model for understanding the fundamental aspects of auditory biology, substantiated by their use for over 40 years. In this protocol, we present a modernised inner ear explant technique that employs organotypic cell culture inserts and serum free media. This approach decreases the likelihood of explant damage by eliminating the need for adhesive substances. Serum free media also restricts excessive cellular outgrowth and inter-experimental variability, both of which are side effects of exogenous serum addition to cell cultures. The protocol described can be applied to culture both cochlear and vestibular explants from various mammals. Example outcomes are demonstrated by immunohistochemistry, hair cell quantification, and electrophysiological recordings to validate the versatility and viability of the protocol.
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Affiliation(s)
- Jacqueline M. Ogier
- Department of Genetics, The Murdoch Children's Research Institute, Parkville, VIC, Australia
- Department of Paediatrics, The University of Melbourne, Parkville, VIC, Australia
| | - Rachel A. Burt
- Department of Genetics, The Murdoch Children's Research Institute, Parkville, VIC, Australia
- Department of Paediatrics, The University of Melbourne, Parkville, VIC, Australia
- Department of Genetics, The University of Melbourne, Parkville, VIC, Australia
| | - Hannah R. Drury
- School of Biomedical Sciences and Pharmacy, The University of Newcastle, Callaghan, NSW, Australia
| | - Rebecca Lim
- School of Biomedical Sciences and Pharmacy, The University of Newcastle, Callaghan, NSW, Australia
| | - Bryony A. Nayagam
- Department of Audiology and Speech Pathology, The University of Melbourne, Parkville, VIC, Australia
- The Bionics Institute, East Melbourne, VIC, Australia
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13
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Kayyali MN, Brake L, Ramsey AJ, Wright AC, O'Malley BW, Li DD. A Novel Nano-approach for Targeted Inner Ear Imaging. ACTA ACUST UNITED AC 2017; 8. [PMID: 29104815 PMCID: PMC5669391 DOI: 10.4172/2157-7439.1000456] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
During the last decade, there have been major improvements in imaging modalities and the development of molecular imaging in general. However detailed inner ear imaging still provides very limited information to physicians. This is unsatisfactory as sensorineural hearing loss is the main cause of permanent hearing loss in adults and at least 134 genetic mutations that result in congenital hearing loss have been identified. We are still unable, in most cases where gross anatomical changes are not observed, to determine the exact cause of hearing loss at a cellular or molecular level in patients using non-invasive techniques. This limitation in inner ear diagnostic modalities is a major obstacle behind the delay in discovering treatments for many of the causes of sensorineural hearing loss. This paper initially investigated the use of targeted gold nanoparticles as contrast agents for inner ear imaging. These nanoparticles have many useful characteristics such as being easy to target and possessing minimal cytotoxicity. We were able to detect the nanoparticles diffusing in the hair cells using confocal microscopy. Regrettably, despite their many admirable characteristics, the gold nanoparticles were unable to significantly enhance CT imaging of the inner ear. Consequently, we investigated liposomal iodine as a potential solution for the unsatisfactory CT contrast obtained with the gold nanoparticles. Fortunately, significant enhancement of the micro-CT image was observed with either Lugol’s solution or liposomal iodine, with Lugol’s solution enabling fine inner ear structures to be detected.
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Affiliation(s)
- M N Kayyali
- Department of Otolaryngology, Head & Neck Surgery, University of Pennsylvania Health System, Philadelphia, USA
| | - L Brake
- Department of Otolaryngology, Head & Neck Surgery, University of Pennsylvania Health System, Philadelphia, USA
| | - A J Ramsey
- Department of Otolaryngology, Head & Neck Surgery, University of Pennsylvania Health System, Philadelphia, USA
| | - A C Wright
- Department of Radiology, University of Pennsylvania, USA
| | - B W O'Malley
- Department of Otolaryngology, Head & Neck Surgery, University of Pennsylvania Health System, Philadelphia, USA
| | - D Daqing Li
- Department of Otolaryngology, Head & Neck Surgery, University of Pennsylvania Health System, Philadelphia, USA
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14
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Abstract
HEI-OC1 is one of the few mouse auditory cell lines available for research purposes. Originally proposed as an in vitro system for screening of ototoxic drugs, these cells have been used to investigate drug-activated apoptotic pathways, autophagy, senescence, mechanism of cell protection, inflammatory responses, cell differentiation, genetic and epigenetic effects of pharmacological drugs, effects of hypoxia, oxidative and endoplasmic reticulum stress, and expression of molecular channels and receptors. Among other several important markers of cochlear hair cells, HEI-OC1 cells endogenously express prestin, the paradigmatic motor protein of outer hair cells. Thus, they can be very useful to elucidate novel functional aspects of this important auditory protein. HEI-OC1 cells are very robust, and their culture usually does not present big complications. However, they require some special conditions such as avoiding the use of common anti-bacterial cocktails containing streptomycin or other antibiotics as well as incubation at 33 °C to stimulate cell proliferation and incubation at 39 °C to trigger cell differentiation. Here, we describe how to culture HEI-OC1 cells and how to use them in some typical assays, such as cell proliferation, viability, death, autophagy and senescence, as well as how to perform patch-clamp and non-linear capacitance measurements.
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Affiliation(s)
- Gilda M Kalinec
- Head and Neck Surgery, David Geffen School of Medicine, University of California, Los Angeles
| | - Channy Park
- Head and Neck Surgery, David Geffen School of Medicine, University of California, Los Angeles
| | - Pru Thein
- Head and Neck Surgery, David Geffen School of Medicine, University of California, Los Angeles
| | - Federico Kalinec
- Head and Neck Surgery, David Geffen School of Medicine, University of California, Los Angeles;
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