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Choi JS, Ahn YJ, Lee S, Park DJ, Park J, Ha SM, Seo YJ. Role of Kir4.1 Channels in Aminoglycoside-Induced Ototoxicity of Hair Cells. Biomed Res Int 2023; 2023:4191999. [PMID: 38143588 PMCID: PMC10748730 DOI: 10.1155/2023/4191999] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/12/2022] [Revised: 10/27/2023] [Accepted: 11/14/2023] [Indexed: 12/26/2023]
Abstract
The Kir4.1 channel, an inwardly rectifying potassium ion (K+) channel, is located in the hair cells of the organ of Corti as well as the intermediate cells of the stria vascularis. The Kir4.1 channel has a crucial role in the generation of endolymphatic potential and maintenance of the resting membrane potential. However, the role and functions of the Kir4.1 channel in the progenitor remain undescribed. To observe the role of Kir4.1 in the progenitor treated with the one-shot ototoxic drugs (kanamycin and furosemide), we set the proper condition in culturing Immortomouse-derived HEI-OC1 cells to express the potassium-related channels well. And also, that was reproduced in mice experiments to show the important role of Kir4.1 in the survival of hair cells after treating the ototoxicity drugs. In our results, when kanamycin and furosemide drugs were cotreated with HEI-OC1 cells, the Kir4.1 channel did not change, but the expression levels of the NKCC1 cotransporter and KCNQ4 channel are decreased. This shows that inward and outward channels were blocked by the two drugs (kanamycin and furosemide). However, noteworthy here is that the expression level of Kir4.1 channel increased when kanamycin was treated alone. This shows that Kir4.1, an inwardly rectifying potassium channel, acts as an outward channel in place of the corresponding channel when the KCNQ4 channel, an outward channel, is blocked. These results suggest that the Kir4.1 channel has a role in maintaining K+ homeostasis in supporting cells, with K+ concentration compensator when the NKCC1 cotransporter and Kv7.4 (KCNQ4) channels are deficient.
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Affiliation(s)
- Jin Sil Choi
- Research Institute of Hearing Enhancement, Yonsei University Wonju College of Medicine, Wonju, Republic of Korea
- Department of Otorhinolaryngology, Yonsei University Wonju College of Medicine, Wonju, Republic of Korea
| | - Ye Ji Ahn
- Research Institute of Hearing Enhancement, Yonsei University Wonju College of Medicine, Wonju, Republic of Korea
- Department of Otorhinolaryngology, Yonsei University Wonju College of Medicine, Wonju, Republic of Korea
| | - SuHoon Lee
- Research Institute of Hearing Enhancement, Yonsei University Wonju College of Medicine, Wonju, Republic of Korea
- Department of Otorhinolaryngology, Yonsei University Wonju College of Medicine, Wonju, Republic of Korea
| | - Dong Jun Park
- Research Institute of Hearing Enhancement, Yonsei University Wonju College of Medicine, Wonju, Republic of Korea
- Department of Otorhinolaryngology, Yonsei University Wonju College of Medicine, Wonju, Republic of Korea
| | - JeongEun Park
- Research Institute of Hearing Enhancement, Yonsei University Wonju College of Medicine, Wonju, Republic of Korea
- Department of Otorhinolaryngology, Yonsei University Wonju College of Medicine, Wonju, Republic of Korea
| | - Sun Mok Ha
- Research Institute of Hearing Enhancement, Yonsei University Wonju College of Medicine, Wonju, Republic of Korea
- Department of Otorhinolaryngology, Yonsei University Wonju College of Medicine, Wonju, Republic of Korea
| | - Young Joon Seo
- Research Institute of Hearing Enhancement, Yonsei University Wonju College of Medicine, Wonju, Republic of Korea
- Department of Otorhinolaryngology, Yonsei University Wonju College of Medicine, Wonju, Republic of Korea
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Bai Y, Liu J, Wu X, Pang B, Zhang S, Jiang M, Chen A, Huang H, Chen Y, Zeng Y, Mei L, Gao K. Susceptibility of immature spiral ganglion neurons to aminoglycoside-induced ototoxicity is mediated by the TRPV1 channel in mice. Hear Res 2023; 440:108910. [PMID: 37956582 DOI: 10.1016/j.heares.2023.108910] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/31/2022] [Revised: 10/23/2023] [Accepted: 11/02/2023] [Indexed: 11/15/2023]
Abstract
Aminoglycoside antibiotics are among the most common agents that can cause sensorineural hearing loss. From clinical experience, premature babies, whose inner ear is still developing, are more susceptible to aminoglycoside-induced ototoxicity, which is echoed by our previous study carried out in organotypic cultures. This study aimed to investigate whether a nonselective cation channel, TRPV1, contributes to the susceptibility of immature spiral ganglion neurons (SGNs) to the damage caused by aminoglycosides. Through western blotting and immunofluorescence, we found that the TRPV1 expression levels were much higher in immature SGNs than in their mature counterparts. In postnatal day 7 cochlear organotypic cultures, AMG-517 reduced reactive oxygen species generation and inhibited SGN apoptosis under aminoglycoside challenge. However, in adult mice, AMG-517 did not ameliorate the ABR threshold increase at high frequencies (16 kHz and 32 kHz) after aminoglycoside administration, and the SGNs within the cochleae had no morphological changes. By further regulating the function of TRPV1 in primary cultured SGNs with its inhibitor AMG-517 and agonist capsaicin, we demonstrated that TRPV1 is a major channel for aminoglycoside uptake: AMG-517 can significantly reduce, while capsaicin can significantly increase, the uptake of GTTR. In addition, TRPV1 knockdown in SGNs can also significantly reduce the uptake of GTTR. Taken together, our results demonstrated that aminoglycosides can directly enter immature SGNs through the TRPV1 channel. High expression of TRPV1 contributes to the susceptibility of immature SGNs to aminoglycoside-induced damage. The TRPV1 inhibitor AMG-517 has the potential to be a therapeutic agent for preventing aminoglycoside-induced ototoxicity in immature SGNs.
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Affiliation(s)
- Yijiang Bai
- Department of Otorhinolaryngology, Xiangya Hospital Central South University, Changsha, PR China; Province Key Laboratory of Otolaryngology Critical Diseases, Changsha, PR China; Department of Geriatrics, National Clinical Research Centre for Geriatric Disorders, Xiangya Hospital, Central South University, Changsha, PR China
| | - Jing Liu
- Department of Otorhinolaryngology, Xiangya Hospital Central South University, Changsha, PR China; Province Key Laboratory of Otolaryngology Critical Diseases, Changsha, PR China; Department of Geriatrics, National Clinical Research Centre for Geriatric Disorders, Xiangya Hospital, Central South University, Changsha, PR China
| | - Xuewen Wu
- Department of Otorhinolaryngology, Xiangya Hospital Central South University, Changsha, PR China; Province Key Laboratory of Otolaryngology Critical Diseases, Changsha, PR China; Department of Geriatrics, National Clinical Research Centre for Geriatric Disorders, Xiangya Hospital, Central South University, Changsha, PR China
| | - Bo Pang
- Department of Otorhinolaryngology, Xiangya Hospital Central South University, Changsha, PR China; Province Key Laboratory of Otolaryngology Critical Diseases, Changsha, PR China; Department of Geriatrics, National Clinical Research Centre for Geriatric Disorders, Xiangya Hospital, Central South University, Changsha, PR China; Hunan Key Laboratory of Medical Genetics, School of Life Sciences, Central South University, Changsha, Hunan, PR China
| | - Shuai Zhang
- Department of Otorhinolaryngology, Xiangya Hospital Central South University, Changsha, PR China; Province Key Laboratory of Otolaryngology Critical Diseases, Changsha, PR China; Department of Geriatrics, National Clinical Research Centre for Geriatric Disorders, Xiangya Hospital, Central South University, Changsha, PR China
| | - Mengzhu Jiang
- Department of Otorhinolaryngology, Xiangya Hospital Central South University, Changsha, PR China; Province Key Laboratory of Otolaryngology Critical Diseases, Changsha, PR China; Department of Geriatrics, National Clinical Research Centre for Geriatric Disorders, Xiangya Hospital, Central South University, Changsha, PR China
| | - Anhai Chen
- Department of Otorhinolaryngology, Xiangya Hospital Central South University, Changsha, PR China; Province Key Laboratory of Otolaryngology Critical Diseases, Changsha, PR China; Department of Geriatrics, National Clinical Research Centre for Geriatric Disorders, Xiangya Hospital, Central South University, Changsha, PR China
| | - Huping Huang
- Department of Otorhinolaryngology, Xiangya Hospital Central South University, Changsha, PR China; Province Key Laboratory of Otolaryngology Critical Diseases, Changsha, PR China; Department of Geriatrics, National Clinical Research Centre for Geriatric Disorders, Xiangya Hospital, Central South University, Changsha, PR China
| | - Yongjia Chen
- Department of Otorhinolaryngology, Xiangya Hospital Central South University, Changsha, PR China; Province Key Laboratory of Otolaryngology Critical Diseases, Changsha, PR China; Department of Geriatrics, National Clinical Research Centre for Geriatric Disorders, Xiangya Hospital, Central South University, Changsha, PR China
| | - Yuan Zeng
- Patient Service Center, Xiangya Hospital Central South University, Changsha, PR China
| | - Lingyun Mei
- Department of Otorhinolaryngology, Xiangya Hospital Central South University, Changsha, PR China; Province Key Laboratory of Otolaryngology Critical Diseases, Changsha, PR China; Department of Geriatrics, National Clinical Research Centre for Geriatric Disorders, Xiangya Hospital, Central South University, Changsha, PR China.
| | - Kelei Gao
- Department of Otorhinolaryngology, Xiangya Hospital Central South University, Changsha, PR China; Province Key Laboratory of Otolaryngology Critical Diseases, Changsha, PR China; Department of Geriatrics, National Clinical Research Centre for Geriatric Disorders, Xiangya Hospital, Central South University, Changsha, PR China.
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3
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Guo J, Mei H, Zhang Y, Che C, Guo L, Zhang Y, Li H, Sun S. Glutamate-aspartate transporter dysfunction enhances aminoglycoside-induced cochlear hair cell death via NMDA receptor activation. Neurochem Int 2023; 169:105587. [PMID: 37495172 DOI: 10.1016/j.neuint.2023.105587] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2023] [Revised: 07/02/2023] [Accepted: 07/23/2023] [Indexed: 07/28/2023]
Abstract
Glutamate is a crucial neurotransmitter for hearing transduction in the cochlea, but excess glutamate is detrimental to the survival of cochlear sensory cells. Glutamate-aspartate transporter (GLAST) is the major transporter for glutamate removal; however, its role in aminoglycoside-induced hair cell loss is not well studied. In the present study, we first investigated the localization and expression of GLAST over the course of development of the mouse cochlea, and we found that inhibition of GLAST increased hair cell death. However, when the glutamate receptor NMDAR was inhibited by D-AP5, hair cell death was no longer increased by the GLAST inhibitor. Our results indicate that GLAST inhibition aggravates damage to cochlear hair cells, which may occur via NMDAR, and this suggests new clinical strategies for ameliorating the ototoxicity associated with the dysfunction of glutamate metabolism.
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Affiliation(s)
- Jin Guo
- ENT Institute and Otorhinolaryngology Department of Eye & ENT Hospital, State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science, Fudan University, Shanghai, 200031, China; NHC Key Laboratory of Hearing Medicine, Fudan University, Shanghai, 200031, China
| | - Honglin Mei
- ENT Institute and Otorhinolaryngology Department of Eye & ENT Hospital, State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science, Fudan University, Shanghai, 200031, China; NHC Key Laboratory of Hearing Medicine, Fudan University, Shanghai, 200031, China
| | - Yanping Zhang
- ENT Institute and Otorhinolaryngology Department of Eye & ENT Hospital, State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science, Fudan University, Shanghai, 200031, China; NHC Key Laboratory of Hearing Medicine, Fudan University, Shanghai, 200031, China
| | - Chenhao Che
- ENT Institute and Otorhinolaryngology Department of Eye & ENT Hospital, State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science, Fudan University, Shanghai, 200031, China; NHC Key Laboratory of Hearing Medicine, Fudan University, Shanghai, 200031, China
| | - Luo Guo
- ENT Institute and Otorhinolaryngology Department of Eye & ENT Hospital, State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science, Fudan University, Shanghai, 200031, China; NHC Key Laboratory of Hearing Medicine, Fudan University, Shanghai, 200031, China
| | - Yunzhong Zhang
- ENT Institute and Otorhinolaryngology Department of Eye & ENT Hospital, State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science, Fudan University, Shanghai, 200031, China; NHC Key Laboratory of Hearing Medicine, Fudan University, Shanghai, 200031, China
| | - Huawei Li
- ENT Institute and Otorhinolaryngology Department of Eye & ENT Hospital, State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science, Fudan University, Shanghai, 200031, China; NHC Key Laboratory of Hearing Medicine, Fudan University, Shanghai, 200031, China; Institutes of Biomedical Sciences, Fudan University, Shanghai, 200032, China; The Institutes of Brain Science and the Collaborative Innovation Center for Brain Science, Fudan University, Shanghai, 200032, China.
| | - Shan Sun
- ENT Institute and Otorhinolaryngology Department of Eye & ENT Hospital, State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science, Fudan University, Shanghai, 200031, China; NHC Key Laboratory of Hearing Medicine, Fudan University, Shanghai, 200031, China.
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4
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Li J, Liu C, Müller U, Zhao B. Autophagy proteins are essential for aminoglycoside-induced hearing loss. Autophagy 2023; 19:1599-1600. [PMID: 36184596 PMCID: PMC10240987 DOI: 10.1080/15548627.2022.2127525] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2022] [Revised: 09/19/2022] [Accepted: 09/19/2022] [Indexed: 11/02/2022] Open
Abstract
Aminoglycosides (AGs) are widely used to treat severe infections. However, systemically administered AGs preferentially kill cochlear hair cells, resulting in irreversible hearing loss. Recently, we found that AGs bind to RIPOR2 and trigger its rapid translocation in cochlear hair cells. Reducing RIPOR2 expression entirely prevents AG-induced hair cell death and subsequent hearing loss in mice. Next using yeast two-hybrid screening, we found that RIPOR2 interacts with GABARAP, a key macroautophagy/autophagy pathway protein. Following AG treatment, RIPOR2 colocalizes with GABARAP and regulates the activation of autophagy. Remarkably, reducing the expression of GABARAP, or another key autophagy protein MAP1LC3B/LC3B, entirely prevents AG-induced hair cell death and subsequent hearing loss in mice. Furthermore, we found that AGs activate the autophagy pathway specific to mitochondria. Reducing the expression of PINK1 or PRKN/parkin, two key mitophagy proteins, protects hair cells against AG toxicity. Thus, our findings demonstrated that RIPOR2-mediated autophagic dysfunction is essential for AG-induced hearing loss and provided potential therapeutic strategies for preventing AG toxicity.
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Affiliation(s)
- Jinan Li
- Department of Otolaryngology-Head and Neck Surgery, Indiana University School of Medicine, Indianapolis, IN, USA
| | - Chang Liu
- Department of Otolaryngology-Head and Neck Surgery, Indiana University School of Medicine, Indianapolis, IN, USA
| | - Ulrich Müller
- The Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Bo Zhao
- Department of Otolaryngology-Head and Neck Surgery, Indiana University School of Medicine, Indianapolis, IN, USA
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Rahman MT, Bailey EM, Gansemer BM, Pieper AA, Manak JR, Green SH. Anti-inflammatory Therapy Protects Spiral Ganglion Neurons After Aminoglycoside Antibiotic-Induced Hair Cell Loss. Neurotherapeutics 2023; 20:578-601. [PMID: 36697994 PMCID: PMC10121993 DOI: 10.1007/s13311-022-01336-2] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/06/2022] [Indexed: 01/26/2023] Open
Abstract
Destruction of cochlear hair cells by aminoglycoside antibiotics leads to gradual death of the spiral ganglion neurons (SGNs) that relay auditory information to the brain, potentially limiting the efficacy of cochlear implants. Because the reasons for this cochlear neurodegeneration are unknown, there are no neuroprotective strategies for patients. To investigate this problem, we assessed transcriptomic changes in the rat spiral ganglion following aminoglycoside antibiotic (kanamycin)-induced hair cell destruction. We observed selectively increased expression of immune and inflammatory response genes and increased abundance of activated macrophages in spiral ganglia by postnatal day 32 in kanamycin-deafened rats, preceding significant SGN degeneration. Treatment with the anti-inflammatory medications dexamethasone and ibuprofen diminished long-term SGN degeneration. Ibuprofen and dexamethasone also diminished macrophage activation. Efficacy of ibuprofen treatment was augmented by co-administration of the nicotinamide adenine dinucleotide-stabilizing agent P7C3-A20. Our results support a critical role of neuroinflammation in SGN degeneration after aminoglycoside antibiotic-mediated cochlear hair cell loss, as well as a neuroprotective strategy that could improve cochlear implant efficacy.
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Affiliation(s)
- Muhammad T Rahman
- Department of Biology, University of Iowa, Iowa City, IA, 52242, USA
| | - Erin M Bailey
- Department of Biology, University of Iowa, Iowa City, IA, 52242, USA
| | | | - Andrew A Pieper
- Harrington Discovery Institute, University Hospitals Cleveland Medical Center, Cleveland, OH, 44106, USA
- Department of Psychiatry, Case Western Reserve University, Cleveland, OH, 44106, USA
- Geriatric Psychiatry, GRECC, Louis Stokes Cleveland VA Medical Center, Cleveland, OH, 44106, USA
- Institute for Transformative Molecular Medicine, School of Medicine, Case Western Reserve University, Cleveland, OH, 44106, USA
| | - J Robert Manak
- Department of Biology, University of Iowa, Iowa City, IA, 52242, USA
- Department of Pediatrics, University of Iowa, Iowa City, IA, 52242, USA
| | - Steven H Green
- Department of Biology, University of Iowa, Iowa City, IA, 52242, USA.
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6
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Ioannidis K, Cohen A, Ghosheh M, Ehrlich A, Fischer A, Cohen M, Nahmias Y. Aminoglycoside-induced lipotoxicity and its reversal in kidney on chip. Lab Chip 2022; 22:4469-4480. [PMID: 36281785 DOI: 10.1039/d2lc00825d] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
Aminoglycosides are an important class of antibiotics that play a critical role in the treatment of life-threatening infections, but their use is limited by their toxicity. In fact, gentamicin causes severe nephrotoxicity in 17% of hospitalized patients. The kidney proximal tubule is particularly vulnerable to drug-induced nephrotoxicity due to its role in drug transport. In this work, we developed a perfused vascularized model of human kidney tubuloids integrated with tissue-embedded microsensors that track the metabolic dynamics of aminoglycoside-induced renal toxicity in real time. Our model shows that gentamicin disrupts proximal tubule polarity at concentrations 20-fold below its TC50, leading to a 3.2-fold increase in glucose uptake, and reverse TCA cycle flux culminating in a 40-fold increase in lipid accumulation. Blocking glucose reabsorption using the SGLT2 inhibitor empagliflozin significantly reduced gentamicin toxicity by 10-fold. These results demonstrate the utility of sensor-integrated kidney-on-chip platforms to rapidly identify new metabolic mechanisms that may underly adverse drug reactions. The results should improve our ability to modulate the toxicity of novel aminoglycosides.
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Affiliation(s)
- Konstantinos Ioannidis
- Grass Center for Bioengineering, Benin School of Computer Science and Engineering, The Hebrew University of Jerusalem, Jerusalem 91904, Israel.
| | - Aaron Cohen
- Grass Center for Bioengineering, Benin School of Computer Science and Engineering, The Hebrew University of Jerusalem, Jerusalem 91904, Israel.
- Department of Cell and Developmental Biology, Silberman Institute of Life Sciences, The Hebrew University of Jerusalem, Jerusalem 91904, Israel
| | - Mohammad Ghosheh
- Grass Center for Bioengineering, Benin School of Computer Science and Engineering, The Hebrew University of Jerusalem, Jerusalem 91904, Israel.
- Department of Cell and Developmental Biology, Silberman Institute of Life Sciences, The Hebrew University of Jerusalem, Jerusalem 91904, Israel
| | - Avner Ehrlich
- Grass Center for Bioengineering, Benin School of Computer Science and Engineering, The Hebrew University of Jerusalem, Jerusalem 91904, Israel.
- Department of Cell and Developmental Biology, Silberman Institute of Life Sciences, The Hebrew University of Jerusalem, Jerusalem 91904, Israel
- Tissue Dynamics, Jerusalem 91904, Israel
| | - Amit Fischer
- Department of Biological Chemistry, Institute of Chemistry, The Hebrew University of Jerusalem, Jerusalem 91904, Israel
| | - Merav Cohen
- Grass Center for Bioengineering, Benin School of Computer Science and Engineering, The Hebrew University of Jerusalem, Jerusalem 91904, Israel.
- Department of Cell and Developmental Biology, Silberman Institute of Life Sciences, The Hebrew University of Jerusalem, Jerusalem 91904, Israel
| | - Yaakov Nahmias
- Grass Center for Bioengineering, Benin School of Computer Science and Engineering, The Hebrew University of Jerusalem, Jerusalem 91904, Israel.
- Department of Cell and Developmental Biology, Silberman Institute of Life Sciences, The Hebrew University of Jerusalem, Jerusalem 91904, Israel
- Tissue Dynamics, Jerusalem 91904, Israel
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Li J, Liu C, Müller U, Zhao B. RIPOR2-mediated autophagy dysfunction is critical for aminoglycoside-induced hearing loss. Dev Cell 2022; 57:2204-2220.e6. [PMID: 36113482 PMCID: PMC9529990 DOI: 10.1016/j.devcel.2022.08.011] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2022] [Revised: 07/25/2022] [Accepted: 08/23/2022] [Indexed: 01/18/2023]
Abstract
Aminoglycosides (AGs) are potent antibiotics that are capable of treating a wide variety of life-threatening infections; however, they are ototoxic and cause irreversible damage to cochlear hair cells. Despite substantial progress, little is known about the molecular pathways critical for hair cell function and survival that are affected by AG exposure. We demonstrate here that gentamicin, a representative AG antibiotic, binds to and within minutes triggers translocation of RIPOR2 in murine hair cells from stereocilia to the pericuticular area. Then, by interacting with a central autophagy component, GABARAP, RIPOR2 affects autophagy activation. Reducing the expression of RIPOR2 or GABARAP completely prevents AG-induced hair cell death and subsequent hearing loss in mice. Additionally, abolishing the expression of PINK1 or Parkin, two key mitochondrial autophagy proteins, prevents hair cell death and subsequent hearing loss caused by AG. In summary, our study demonstrates that RIPOR2-mediated autophagic dysfunction is essential for AG-induced hearing loss.
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Affiliation(s)
- Jinan Li
- Department of Otolaryngology-Head and Neck Surgery, Indiana University School of Medicine, Indianapolis, IN 46202, USA
| | - Chang Liu
- Department of Otolaryngology-Head and Neck Surgery, Indiana University School of Medicine, Indianapolis, IN 46202, USA
| | - Ulrich Müller
- The Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Bo Zhao
- Department of Otolaryngology-Head and Neck Surgery, Indiana University School of Medicine, Indianapolis, IN 46202, USA.
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Kim J, Hemachandran S, Cheng AG, Ricci AJ. Identifying targets to prevent aminoglycoside ototoxicity. Mol Cell Neurosci 2022; 120:103722. [PMID: 35341941 PMCID: PMC9177639 DOI: 10.1016/j.mcn.2022.103722] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2021] [Revised: 03/14/2022] [Accepted: 03/19/2022] [Indexed: 12/21/2022] Open
Abstract
Aminoglycosides are potent antibiotics that are commonly prescribed worldwide. Their use carries significant risks of ototoxicity by directly causing inner ear hair cell degeneration. Despite their ototoxic side effects, there are currently no approved antidotes. Here we review recent advances in our understanding of aminoglycoside ototoxicity, mechanisms of drug transport, and promising sites for intervention to prevent ototoxicity.
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Affiliation(s)
- Jinkyung Kim
- Department of Otolaryngology-Head and Neck Surgery, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Sriram Hemachandran
- Department of Otolaryngology-Head and Neck Surgery, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Alan G Cheng
- Department of Otolaryngology-Head and Neck Surgery, Stanford University School of Medicine, Stanford, CA 94305, USA.
| | - Anthony J Ricci
- Department of Otolaryngology-Head and Neck Surgery, Stanford University School of Medicine, Stanford, CA 94305, USA; Department of Molecular and Cellular Physiology, Stanford University School of Medicine, Stanford, CA 94305, USA.
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Dhar G, Paikra SK, Mishra M. Aminoglycoside treatment alters hearing-related genes and depicts behavioral defects in Drosophila. Arch Insect Biochem Physiol 2022; 110:e21871. [PMID: 35150449 DOI: 10.1002/arch.21871] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/05/2021] [Revised: 12/30/2021] [Accepted: 01/13/2022] [Indexed: 06/14/2023]
Abstract
The hearing organ of Drosophila is present within the second segment of antennae. The hearing organ of Drosophila (Johnston's organ [JO]) shares much structural, developmental, and functional similarity with the vertebrate hearing organ (Organ of Corti). JO is evolving as a potential model system to examine the hearing-associated defects in vertebrates. In the vertebrates, aminoglycosides like gentamicin, kanamycin, and neomycin have been known to cause defects in the hearing organ. However, a complete mechanism of toxicity is not known. Taking the evolutionary conservation into account the current study aims to test various concentrations of aminoglycoside on the model organism, Drosophila melanogaster. The current study uses the oral route to check the toxicity of various aminoglycosides at different concentrations (50, 100, 150, 200, and 250 μg ml- 1 ). In Drosophila, many foreign particles enter the body through the gut via food. The aminoglycoside treated third instar larvae show defective crawling and sound avoidance behavior. The adult flies release lower amounts of acetylcholine esterase and higher amounts of reactive oxygen species than control untreated animals, accompanied by defective climbing and aggressive behavior. All these behavioral defects are further confirmed by the altered expression level of hearing genes such as nompC, inactive, nanchung, pyrexia. All the behavioral and genetic defects are reported as a readout of aminoglycoside toxicity.
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Affiliation(s)
- Gyanaseni Dhar
- Department of Life Science, Neural Developmental Biology Lab, National Institute of Technology, Rourkela, Rourkela, Odisha, India
| | - Sanjeev K Paikra
- Department of Life Science, Neural Developmental Biology Lab, National Institute of Technology, Rourkela, Rourkela, Odisha, India
| | - Monalisa Mishra
- Department of Life Science, Neural Developmental Biology Lab, National Institute of Technology, Rourkela, Rourkela, Odisha, India
- Centre for Nanomaterials, National Institute of technology Rourkela, Rourkela, Odisha, India
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10
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Tawde M, Bior A, Feiss M, Teng F, Freimuth P. A polypeptide model for toxic aberrant proteins induced by aminoglycoside antibiotics. PLoS One 2022; 17:e0258794. [PMID: 35486612 PMCID: PMC9053816 DOI: 10.1371/journal.pone.0258794] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2021] [Accepted: 03/01/2022] [Indexed: 11/24/2022] Open
Abstract
Aminoglycoside antibiotics interfere with the selection of cognate tRNAs during translation, resulting in the synthesis of aberrant proteins that are the ultimate cause of cell death. However, the toxic potential of aberrant proteins and how they avoid degradation by the cell’s protein quality control (QC) machinery are not understood. Here we report that levels of the heat shock (HS) transcription factor σ32 increased sharply following exposure of Escherichia coli to the aminoglycoside kanamycin (Kan), suggesting that at least some of the aberrant proteins synthesized in these cells were recognized as substrates by DnaK, a molecular chaperone that regulates the HS response, the major protein QC pathway in bacteria. To further investigate aberrant protein toxic potential and interaction with cell QC factors, we studied an acutely toxic 48-residue polypeptide (ARF48) that is encoded by an alternate reading frame in a plant cDNA. As occurred in cells exposed to Kan, σ32 levels were strongly elevated following ARF48 expression, suggesting that ARF48 was recognized as a substrate by DnaK. Paradoxically, an internal 10-residue region that was tightly bound by DnaK in vitro also was required for the ARF48 toxic effect. Despite the increased levels of σ32, levels of several HS proteins were unchanged following ARF48 expression, suggesting that the HS response had been aborted. Nucleoids were condensed and cell permeability increased rapidly following ARF48 expression, together suggesting that ARF48 disrupts DNA-membrane interactions that could be required for efficient gene expression. Our results are consistent with earlier studies showing that aberrant proteins induced by aminoglycoside antibiotics disrupt cell membrane integrity. Insights into the mechanism for this effect could be gained by further study of the ARF48 model system.
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Affiliation(s)
- Mangala Tawde
- Department of Biological Sciences and Geology, Queensborough Community College, City University of New York, Bayside, New York, United States of America
| | - Abdelaziz Bior
- Department of Natural and Applied Sciences, Cheyney University of Pennsylvania, Cheyney, Pennsylvania, United States of America
| | - Michael Feiss
- Department of Microbiology and Immunology, University of Iowa Carver College of Medicine, Iowa City, Iowa, United States of America
| | - Feiyue Teng
- Center for Functional Nanomaterials, Brookhaven National Laboratory, Upton, New York, United States of America
| | - Paul Freimuth
- Biology Department, Brookhaven National Laboratory, Upton, New York, United States of America
- * E-mail:
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Iqbal MO, Yahya EB. In vivo assessment of reversing aminoglycoside antibiotics nephrotoxicity using Jatropha mollissima crude extract. Tissue Cell 2021; 72:101525. [PMID: 33780659 DOI: 10.1016/j.tice.2021.101525] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2021] [Revised: 02/18/2021] [Accepted: 03/07/2021] [Indexed: 01/30/2023]
Abstract
Aminoglycoside antibiotics are widely employed clinically due to their powerful bactericidal activities, less bacterial resistance compared to beta lactam group and low cost. However, their use has been limited in recent years due to their potential induction of nephrotoxicity. Here we investigate the possibility of reversing nephrotoxicity caused by gentamicin in rat models by using ethanolic crude extract of the medicinal plant Jatropha Mollissima. Nephrotoxic male Wistar rats was obtained by gentamicin antibiotic, which then treated with two doses of J. mollissima crude extract for 3 weeks with monitoring their parameter in weekly base. Our results indicate that J. mollissima crude extract at both doses has strong protection ability against gentamicin nephrotoxicity, most of tested parameters backed to normal values after few days from the administration of the crude extract, which could be due to the antagonized the biochemical action of gentamicin on the proximal tubules of the kidney. The results of histopathologic analysis showed observable improvement in J. mollissima treated groups compared with untreated groups. Our findings suggests the J. mollissima has exceptional nephron protection potentials able to reverse the nephrotoxicity caused by gentamicin antibiotic.
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Affiliation(s)
- Muhammad Omer Iqbal
- Key Laboratory of Marine Drugs, Shandong Provincial Key Laboratory of Glycoscience and Glycoengineering, School of Medicine and Pharmacy, Ocean University of China, Qingdao, Shandong, 266003, China
| | - Esam Bashir Yahya
- School of Industrial Technology, Universiti Sains Malaysia, Penang, 11800, Malaysia.
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Jospe-Kaufman M, Siomin L, Fridman M. The relationship between the structure and toxicity of aminoglycoside antibiotics. Bioorg Med Chem Lett 2020; 30:127218. [PMID: 32360102 PMCID: PMC7194799 DOI: 10.1016/j.bmcl.2020.127218] [Citation(s) in RCA: 45] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2020] [Revised: 04/23/2020] [Accepted: 04/24/2020] [Indexed: 02/06/2023]
Abstract
Aminoglycoside antibiotics, used to treat persistent gram-negative infections, tuberculosis, and life-threatening infections in neonates and patients with cystic fibrosis, can infer acute kidney injury and irreversible hearing loss. The full repertoire of cellular targets and processes leading to the toxicity of aminoglycosides is not fully resolved, making it challenging to devise rational directions to circumvent their adverse effects. As a result, there has been very limited effort to rationally address the issue of aminoglycoside-induced toxicity. Here we provide an overview of the reported effects of aminoglycosides on cells of the inner ear and on kidney tubular epithelial cells. We describe selected examples for structure–toxicity relationships established by evaluation of both natural and semisynthetic aminoglycosides. The various assays and models used to evaluate these antibiotics and recent progress in development of safer aminoglycoside antibiotics are discussed.
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Affiliation(s)
- Moriah Jospe-Kaufman
- School of Chemistry, Raymond and Beverley Sackler Faculty of Exact Sciences, Tel Aviv University, Tel Aviv 6997801, Israel
| | - Liza Siomin
- Department of Human Molecular Genetics & Biochemistry, Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv 6997801, Israel
| | - Micha Fridman
- School of Chemistry, Raymond and Beverley Sackler Faculty of Exact Sciences, Tel Aviv University, Tel Aviv 6997801, Israel.
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Desa DE, Nichols MG, Smith HJ. Aminoglycosides rapidly inhibit NAD(P)H metabolism increasing reactive oxygen species and cochlear cell demise. J Biomed Opt 2018; 24:1-14. [PMID: 30411553 PMCID: PMC6225535 DOI: 10.1117/1.jbo.24.5.051403] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/10/2018] [Accepted: 09/21/2018] [Indexed: 06/04/2023]
Abstract
Despite causing permanent hearing loss by damaging inner ear sensory cells, aminoglycosides (AGs) remain one of the most widely used classes of antibiotics in the world. Although the mechanisms of cochlear sensory cell damage are not fully known, reactive oxygen species (ROS) are clearly implicated. Mitochondrial-specific ROS formation was evaluated in acutely cultured murine cochlear explants exposed to gentamicin (GM), a representative ototoxic AG antibiotic. Superoxide (O2·-) and hydrogen peroxide (H2O2) were measured using MitoSOX Red and Dihydrorhodamine 123, respectively, in sensory and supporting cells. A 1-h GM exposure significantly increased O2·- formation in IHCs and increased H2O2 formation in all cell types. At the same time point, GM significantly increased manganese superoxide dismutase (MnSOD) levels while significantly decreasing copper/zinc superoxide dismutase (CuZnSOD) in cochlear sensory cells. This suggests (1) a rapid conversion of highly reactive O2·- to H2O2 during the acute stage of ototoxic antibiotic exposure and (2) that the endogenous antioxidant system is significantly altered by AGs. Fluorescence intensity-based measurements of reduced nicotinamide adenine dinucleotide (phosphate) [NAD(P)H] and mitochondrial membrane potential were measured to determine if increases in GM-induced ROS production were correlated with changes in mitochondrial metabolism. This project provides a basis for understanding the mechanisms of mitochondrial ROS production in cochlear cells exposed to ototoxic antibiotics. Understanding the nature of ototoxic antibiotic-induced changes in mitochondrial metabolism is critical for developing hearing loss treatment and prevention strategies.
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Affiliation(s)
- Danielle E. Desa
- University of Rochester, Department of Biomedical Engineering, Rochester, New York, United States
| | - Michael G. Nichols
- Creighton University, Department of Physics, Omaha, Nebraska, United States
- Creighton University, Department of Biomedical Sciences, Omaha, Nebraska, United States
| | - Heather Jensen Smith
- University of Nebraska Medical Center, The Eppley Institute for Cancer and Allied Diseases, Omaha, Nebraska, United States
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Scheibinger M, Ellwanger DC, Corrales CE, Stone JS, Heller S. Aminoglycoside Damage and Hair Cell Regeneration in the Chicken Utricle. J Assoc Res Otolaryngol 2017; 19:17-29. [PMID: 29134476 DOI: 10.1007/s10162-017-0646-4] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2017] [Accepted: 10/30/2017] [Indexed: 12/30/2022] Open
Abstract
In this study, we present a systematic characterization of hair cell loss and regeneration in the chicken utricle in vivo. A single unilateral surgical delivery of streptomycin caused robust decline of hair cell numbers in striolar as well as extrastriolar regions, which in the striola was detected very early, 6 h post-insult. During the initial 12 h of damage response, we observed global repression of DNA replication, in contrast to the natural, mitotic hair cell production in undamaged control utricles. Regeneration of hair cells in striolar and extrastriolar regions occurred via high rates of asymmetric supporting cell divisions, accompanied by delayed replenishment by symmetric division. While asymmetric division of supporting cells is the main regenerative response to aminoglycoside damage, the detection of symmetric divisions supports the concept of direct transdifferentiation where supporting cells need to be replenished after their phenotypic conversion into new hair cells. Supporting cell divisions appear to be well coordinated because total supporting cell numbers throughout the regenerative process were invariant, despite the initial large-scale loss of hair cells. We conclude that a single ototoxic drug application provides an experimental framework to study the precise onset and timing of utricle hair cell regeneration in vivo. Our findings indicate that initial triggers and signaling events occur already within a few hours after aminoglycoside exposure. Direct transdifferentiation and asymmetric division of supporting cells to generate new hair cells subsequently happen largely in parallel and persist for several days.
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Affiliation(s)
- Mirko Scheibinger
- Department of Otolaryngology-Head and Neck Surgery, Stanford University School of Medicine, Stanford, CA, 94305, USA.
| | - Daniel C Ellwanger
- Department of Otolaryngology-Head and Neck Surgery, Stanford University School of Medicine, Stanford, CA, 94305, USA
| | - C Eduardo Corrales
- Department of Otolaryngology-Head and Neck Surgery, Stanford University School of Medicine, Stanford, CA, 94305, USA
- Department of Otology and Laryngology, Harvard Medical School and Brigham and Woman's Hospital, Boston, MA, 02115, USA
| | - Jennifer S Stone
- Department of Otolaryngology-Head and Neck Surgery, Virginia Merrill Bloedel Hearing Research Center, University of Washington, Seattle, WA, 98195, USA
| | - Stefan Heller
- Department of Otolaryngology-Head and Neck Surgery, Stanford University School of Medicine, Stanford, CA, 94305, USA
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Ryals M, Pak K, Jalota R, Kurabi A, Ryan AF. A kinase inhibitor library screen identifies novel enzymes involved in ototoxic damage to the murine organ of Corti. PLoS One 2017; 12:e0186001. [PMID: 29049311 PMCID: PMC5648133 DOI: 10.1371/journal.pone.0186001] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2017] [Accepted: 09/22/2017] [Indexed: 11/25/2022] Open
Abstract
Ototoxicity is a significant side effect of a number of drugs, including the aminoglycoside antibiotics and platinum-based chemotherapeutic agents that are used to treat life-threatening illnesses. Although much progress has been made, the mechanisms that lead to ototoxic loss of inner ear sensory hair cells (HCs) remains incompletely understood. Given the critical role of protein phosphorylation in intracellular processes, including both damage and survival signaling, we screened a library of kinase inhibitors targeting members of all the major families in the kinome. Micro-explants from the organ of Corti of mice in which only the sensory cells express GFP were exposed to 200 μM of the ototoxic aminoglycoside gentamicin with or without three dosages of each kinase inhibitor. The loss of sensory cells was compared to that seen with gentamicin alone, or without treatment. Of the 160 inhibitors, 15 exhibited a statistically significant protective effect, while 3 significantly enhanced HC loss. The results confirm some previous studies of kinase involvement in HC damage and survival, and also highlight several novel potential kinase pathway contributions to ototoxicity.
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Affiliation(s)
- Matthew Ryals
- Department of Surgery/Otolaryngology, University of California, San Diego, School of Medicine, La Jolla, California, United States of America
| | - Kwang Pak
- Department of Surgery/Otolaryngology, University of California, San Diego, School of Medicine, La Jolla, California, United States of America
| | - Rahul Jalota
- Department of Surgery/Otolaryngology, University of California, San Diego, School of Medicine, La Jolla, California, United States of America
| | - Arwa Kurabi
- Department of Surgery/Otolaryngology, University of California, San Diego, School of Medicine, La Jolla, California, United States of America
| | - Allen F. Ryan
- Department of Surgery/Otolaryngology, University of California, San Diego, School of Medicine, La Jolla, California, United States of America
- Research Service, Veterans Administration Medical Center, San Diego, California, United States of America
- * E-mail:
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Hailey DW, Esterberg R, Linbo TH, Rubel EW, Raible DW. Fluorescent aminoglycosides reveal intracellular trafficking routes in mechanosensory hair cells. J Clin Invest 2016; 127:472-486. [PMID: 27991862 DOI: 10.1172/jci85052] [Citation(s) in RCA: 56] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2015] [Accepted: 11/03/2016] [Indexed: 11/17/2022] Open
Abstract
Aminoglycosides (AGs) are broad-spectrum antibiotics that are associated with kidney damage, balance disorders, and permanent hearing loss. This damage occurs primarily by killing of proximal tubule kidney cells and mechanosensory hair cells, though the mechanisms underlying cell death are not clear. Imaging molecules of interest in living cells can elucidate how molecules enter cells, traverse intracellular compartments, and interact with sites of activity. Here, we have imaged fluorescently labeled AGs in live zebrafish mechanosensory hair cells. We determined that AGs enter hair cells via both nonendocytic and endocytic pathways. Both routes deliver AGs from the extracellular space to lysosomes, and structural differences between AGs alter the efficiency of this delivery. AGs with slower delivery to lysosomes were immediately toxic to hair cells, and impeding lysosome delivery increased AG-induced death. Therefore, pro-death cascades induced at early time points of AG exposure do not appear to derive from the lysosome. Our findings help clarify how AGs induce hair cell death and reveal properties that predict toxicity. Establishing signatures for AG toxicity may enable more efficient evaluation of AG treatment paradigms and structural modifications to reduce hair cell damage. Further, this work demonstrates how following fluorescently labeled drugs at high resolution in living cells can reveal important details about how drugs of interest behave.
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Abstract
Spontaneous hypospadias is seldom observed in rats in contrast to its occurrence in 1 out of 250 human births. Ziracin, an antibacterial of the everninomycin class under development for serious enterococcal, staphylococcal, and streptococcal infections, caused anomalies of the external genitalia in F1 female rats and decreased reproductive performance. To characterize the urogenital malformations and determine the period of sensitivity to the effects of Ziracin during development, pregnant rats (F0) were administered 60 mg/kg IV of Ziracin from GD6 to LD21, GD6 to 13, GD14 to the last day of gestation or LD0 to 21. Controls received saline or placebo from GD6 to LD21. Ziracin-induced changes occurred in F1 rats exposed from GD6 to LD21 and GD14 to the last day of gestation, indicating that the period of sensitivity to Ziracin was from GD 14 to the last day of gestation. The urogenital abnormalities consisted of cranial displacement of the urethral opening within the vagina from its normal location at the tip of the genital tubercle. When the urethrovaginal junction occurred at the distal third of the vagina, it created an urogenital cloaca. As a result, ascending infections were seen in the urinary and genital tract. No differences in survivability, body weight, and date of vaginal opening were observed in F1 females. The estrous cycles were slightly prolonged. The mating and fertility indices were decreased as a result of the urogenital anomalies. The mammary glands of pregnant F1 females were underdeveloped, thus F2 pups from affected F1 females had a decreased survival rate. Although the cause of these effects is not known, the findings are consistent with a potential hormonal mechanism.
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Deka SR, Yadav S, Mahato M, Sharma AK. Azobenzene-aminoglycoside: Self-assembled smart amphiphilic nanostructures for drug delivery. Colloids Surf B Biointerfaces 2015; 135:150-157. [PMID: 26255160 DOI: 10.1016/j.colsurfb.2015.07.026] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2015] [Revised: 06/19/2015] [Accepted: 07/09/2015] [Indexed: 12/14/2022]
Abstract
Here, we have designed and synthesized a novel cationic amphiphilic stimuli-responsive azobenzene-aminoglycoside (a small molecule) conjugate, Azo-AG 5, and characterized it by UV and FTIR. Light responsive nature of Azo-AG 5 was assessed under UV-vis light. Self- assembly of Azo-AG 5 in aqueous solutions into nanostructures and their ability to act as drug carrier were also investigated. The nanostructures of Azo-AG 5 showed average hydrodynamic diameter of ∼ 255 nm with aminoglycoside moiety (neomycin) and 4-dimethylaminoazobenzene forming hydrophilic shell and hydrophobic core, respectively. In the hydrophobic core, eosin and aspirin were successfully encapsulated. Dynamic light scattering (DLS) measurements demonstrated that the nanoassemblies showed expansion and contraction on successive UV and visible light irradiations exhibiting reversible on-off switch for controlling the drug release behavior. Similar behavior was observed when these nanostructures were subjected to pH-change. In vitro drug release studies showed a difference in UV and visible light-mediated release pattern. It was observed that the release rate under UV irradiation was comparatively higher than that observed under visible light. Further, azoreductase-mediated cleavage of the azo moiety in Azo-AG 5 nanoassemblies resulted in the dismantling of the structures into aggregated microstructures. Azo-AG 5 nanostructures having positive surface charge (+9.74 mV) successfully interacted with pDNA and retarded its mobility on agarose gel. Stimuli responsiveness of nanostructures and their on-off switch like behavior ensure the great potential as controlled drug delivery systems and in other biomedical applications such as colon-specific delivery and gene delivery.
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Affiliation(s)
- Smriti Rekha Deka
- Nucleic Acids Research Laboratory, CSIR-Institute of Genomics and Integrative Biology, Mall Road, Delhi 110007, India
| | - Santosh Yadav
- Nucleic Acids Research Laboratory, CSIR-Institute of Genomics and Integrative Biology, Mall Road, Delhi 110007, India; Academy of Scientific and Innovative Research, New Delhi, India
| | - Manohar Mahato
- Nucleic Acids Research Laboratory, CSIR-Institute of Genomics and Integrative Biology, Mall Road, Delhi 110007, India
| | - Ashwani Kumar Sharma
- Nucleic Acids Research Laboratory, CSIR-Institute of Genomics and Integrative Biology, Mall Road, Delhi 110007, India.
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Mondorf AW, Schoeppe W. Is the potential nephrotoxicity of drugs predictable? Experiences with a volunteer model. Contrib Nephrol 2015; 42:93-9. [PMID: 6152418 DOI: 10.1159/000409966] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
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Yamauchi T, Uzui K, Nishi R, Shigemi H, Ueda T. Gemtuzumab ozogamicin and olaparib exert synergistic cytotoxicity in CD33-positive HL-60 myeloid leukemia cells. Anticancer Res 2014; 34:5487-5494. [PMID: 25275045] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
BACKGROUND/AIM Gemtuzumab ozogamicin (GO) consists of the cluster of differentiation 33 (CD33) antibody linked to calicheamicin. The binding of GO to the CD33 antigen on leukemic cells results in internalization and subsequent release of calicheamicin, thereby inducing DNA strand breaks. We hypothesized that the poly (ADP-ribose) polymerase inhibitor olaparib might inhibit DNA repair initiated by GO-induced DNA strand breaks, thereby increasing cytotoxicity. MATERIALS AND METHODS The human myeloid leukemia cell line HL-60 and a GO-resistant variant (HL/GO20) were used. RESULTS The 50% growth-inhibitory concentrations (IC50) were 24 ng/ml for HL-60 cells and 550 ng/ml for GO-resistant variant HL/GO20 cells. HL/GO20 cells were also refractory to GO-induced apoptosis. CD33 positivity was reduced in HL/GO20 cells. Olaparib-alone did not inhibit the cell growth and did not induce apoptosis in either HL-60 cells or HL/GO20 cells at concentrations of up to 10 μM. When cells were treated with different concentrations of GO in the presence of 10 μM olaparib, the IC50 of GO for HL-60 cells was 13 ng/ml. The combination index was 0.86, indicating synergistic cytotoxicity of GO and olaparib in combination. Such a combination was ineffective for HL/GO20 cells. CONCLUSION GO and olaparib exerted synergistic cytotoxicity in CD33-positive myeloid leukemia cells in vitro.
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Affiliation(s)
- Takahiro Yamauchi
- Department of Hematology and Oncology, University of Fukui, Eiheiji, Fukui, Japan
| | - Kanako Uzui
- Department of Hematology and Oncology, University of Fukui, Eiheiji, Fukui, Japan
| | - Rie Nishi
- Department of Hematology and Oncology, University of Fukui, Eiheiji, Fukui, Japan
| | - Hiroko Shigemi
- Department of Hematology and Oncology, University of Fukui, Eiheiji, Fukui, Japan
| | - Takanori Ueda
- Department of Hematology and Oncology, University of Fukui, Eiheiji, Fukui, Japan
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Beerman TA, Gawron LS, Shen B, Kennedy DR. The radiomimetic enediyne, 20'-deschloro-C-1027 induces inter-strand DNA crosslinks in hypoxic cells and overcomes cytotoxic radioresistance. DNA Repair (Amst) 2014; 21:165-70. [PMID: 24986640 PMCID: PMC4126566 DOI: 10.1016/j.dnarep.2014.06.001] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2014] [Revised: 06/03/2014] [Accepted: 06/05/2014] [Indexed: 11/29/2022]
Abstract
The ability of the radiomimetic anti-tumor enediyne C-1027 to induce DNA inter-strand crosslinks (ICLs), in addition to the expected DNA strand breaks, is unique among traditional DNA targeted cancer therapies. Importantly, radiation therapy and most radiomimetic drugs have diminished effect in hypoxic environments due to decreased induction of DNA strand breaks, which is an oxygen requiring process. However, C-1027's induction of ICLs is enhanced under hypoxia and it is actually more potent against hypoxic cells, overcoming this common tumor resistance mechanism. In this study, an analog of C-1027, 20'-deschloro-C-1027 was examined for its ability to induce DNA ICLs under hypoxic conditions. Deschloro-induced ICLs were detected under hypoxic cell-free conditions, with a concomitant reduction in the induction of DNA strand breaks. In cells deschloro behaved similarly, inducing cellular ICLs under hypoxic conditions with a reduction in DNA breaks. The cytotoxicity of deschloro treatment was similar in normoxic and hypoxic cells, suggesting that the ICL induction allows deschloro to retain its cytotoxic activity under hypoxia. It appears that rational engineering of the C-1027 family of radiomimetics holds promise toward overcoming the radioresistance associated with the hypoxic environment associated with solid tumors.
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Affiliation(s)
- Terry A Beerman
- Department of Pharmacology and Therapeutics, Roswell Park Cancer Institute, Buffalo, NY, United States
| | - Loretta S Gawron
- Department of Pharmacology and Therapeutics, Roswell Park Cancer Institute, Buffalo, NY, United States
| | - Ben Shen
- Department of Chemistry, The Scripps Research Institute, Jupiter, FL, United States; Department of Molecular Therapeutics, The Scripps Research Institute, Jupiter, FL, United States; Natural Products Library Initiative at The Scripps Research Institute, The Scripps Research Institute, Jupiter, FL, United States
| | - Daniel R Kennedy
- Department of Pharmaceutical Sciences, Western New England University, Springfield, MA, United States.
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Roy S, Ryals MM, Van den Bruele AB, Fitzgerald TS, Cunningham LL. Sound preconditioning therapy inhibits ototoxic hearing loss in mice. J Clin Invest 2014; 123:4945-9. [PMID: 24216513 DOI: 10.1172/jci71353] [Citation(s) in RCA: 60] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2013] [Accepted: 08/12/2013] [Indexed: 01/28/2023] Open
Abstract
Therapeutic drugs with ototoxic side effects cause significant hearing loss for thousands of patients annually. Two major classes of ototoxic drugs are cisplatin and the aminoglycoside antibiotics, both of which are toxic to mechanosensory hair cells, the receptor cells of the inner ear. A critical need exists for therapies that protect the inner ear without inhibiting the therapeutic efficacy of these drugs. The induction of heat shock proteins (HSPs) inhibits both aminoglycoside- and cisplatin-induced hair cell death and hearing loss. We hypothesized that exposure to sound that is titrated to stress the inner ear without causing permanent damage would induce HSPs in the cochlea and inhibit ototoxic drug–induced hearing loss. We developed a sound exposure protocol that induces HSPs without causing permanent hearing loss. We used this protocol in conjunction with a newly developed mouse model of cisplatin ototoxicity and found that preconditioning mouse inner ears with sound has a robust protective effect against cisplatin-induced hearing loss and hair cell death. Sound therapy also provided protection against aminoglycoside-induced hearing loss. These data indicate that sound preconditioning protects against both classes of ototoxic drugs, and they suggest that sound therapy holds promise for preventing hearing loss in patients receiving these drugs.
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Shrestha S, Grilley M, Fosso MY, Chang CWT, Takemoto JY. Membrane lipid-modulated mechanism of action and non-cytotoxicity of novel fungicide aminoglycoside FG08. PLoS One 2013; 8:e73843. [PMID: 24040088 PMCID: PMC3769384 DOI: 10.1371/journal.pone.0073843] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2013] [Accepted: 07/27/2013] [Indexed: 11/30/2022] Open
Abstract
A novel aminoglycoside, FG08, that differs from kanamycin B only by a C8 alkyl chain at the 4″-O position, was previously reported. Unlike kanamycin B, FG08 shows broad-spectrum fungicidal but not anti-bacterial activities. To understand its specificity for fungi, the mechanism of action of FG08 was studied using intact cells of the yeast Saccharomyces cerevisiae and small unilamellar membrane vesicles. With exposure to FG08 (30 µg mL−1), 8-fold more cells were stained with fluorescein isothiocyanate, cells had 4 to 6-fold higher K+ efflux rates, and 18-fold more cells were stained with SYTOX Green in comparison to exposure to kanamycin B (30 µg mL−1). Yeast mutants with aberrant membrane sphingolipids (no sphingoid base C4 hydroxyl group, truncated very long fatty acid chain, or lacking the terminal phosphorylinositol group of mannosyl-diinositolphosphorylphytoceramide were 4 to 8-fold less susceptible to growth inhibition with FG08 and showed 2 to 10-fold lower SYTOX Green dye uptake rates than did the isogenic wild-type strain. FG08 caused leakage of pre-loaded calcein from 50% of small unilamellar vesicles with glycerophospholipid and sterol compositions that mimic the compositions of fungal plasma membranes. Less than 5 and 10% of vesicles with glycerophospholipid and sterol compositions that mimic bacterial and mammalian cell plasma membranes, respectively, showed calcein leakage. In tetrazolium dye cytotoxicity tests, mammalian cell lines NIH3T3 and C8161.9 showed FG08 toxicity at concentrations that were 10 to 20-fold higher than fungicidal minimal inhibitory concentrations. It is concluded that FG08’s growth inhibitory specificity for fungi lie in plasma membrane permeability changes involving mechanisms that are modulated by membrane lipid composition.
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Affiliation(s)
- Sanjib Shrestha
- Department of Biology, Utah State University, Logan, Utah, United States of America
- Synthetic Bioproducts Center (USTAR), Utah State University, North Logan, Utah, United States of America
| | - Michelle Grilley
- Department of Biology, Utah State University, Logan, Utah, United States of America
| | - Marina Y. Fosso
- Department of Chemistry and Biochemistry, Logan, Utah, United States of America
| | - Cheng-Wei T. Chang
- Department of Chemistry and Biochemistry, Logan, Utah, United States of America
| | - Jon Y. Takemoto
- Department of Biology, Utah State University, Logan, Utah, United States of America
- * E-mail:
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Dada AC, Ahmad A, Usup G, Heng LY, Hamid R. High-level aminoglycoside resistance and virulence characteristics among Enterococci isolated from recreational beaches in Malaysia. Environ Monit Assess 2013; 185:7427-7443. [PMID: 23417753 DOI: 10.1007/s10661-013-3110-x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/20/2012] [Accepted: 01/18/2013] [Indexed: 06/01/2023]
Abstract
We report the first study on the occurrence of high-level aminoglycoside-resistant (HLAR) Enterococci in coastal bathing waters and beach sand in Malaysia. None of the encountered isolates were resistant to high levels of gentamicin (500 μg/mL). However, high-level resistance to kanamycin (2,000 μg/mL) was observed in 14.2 % of tested isolates, the highest proportions observed being among beach sand isolates. High-level resistance to kanamycin was higher among Enterococcus faecalis and Enterococcus faecium than Enterococcus spp. Chi-square analysis showed no significant association between responses to tested antibiotics and the species allocation or source of isolation of all tested Enterococci. The species classification of encountered Enterococci resistance to vancomycin was highest among Enterococcus spp. (5.89 %) followed by E. faecium (4.785) and least among E. faecalis. A total of 160 isolates were also tested for virulence characteristics. On the whole, caseinase production was profoundly highest (15.01 %) while the least prevalent virulence characteristic observed among tested beach Enterococci was haemolysis of rabbit blood (3.65 %). A strong association was observed between the source of isolation and responses for each of caseinase (C = 0.47, V = 0.53) and slime (C = 0.50, V = 0.58) assays. Analysis of obtained spearman's coefficient showed a strong correlation between caseinase and each of the slime production (p = 0.04), gelatinase (p = 0.0035) and haemolytic activity on horse blood (p = 0.004), respectively. Suggestively, these are the main virulent characteristics of the studied beach Enterococci. Our findings suggest that recreational beaches may contribute to the dissemination of Enterococci with HLAR and virulence characteristics.
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Affiliation(s)
- Ayokunle Christopher Dada
- Faculty of Science and Technology, School of Biosciences and Biotechnology, Universiti Kebangsaan Malaysia, 43600 UKM Bangi, Selangor, Malaysia.
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Pavlidis P, Maurer J, Apostolidou E, Kekes G, Kouvelas D. Memantine's action against aminoglycoside-induced ototoxicity. Eur Arch Otorhinolaryngol 2013; 271:1491-6. [PMID: 23917735 DOI: 10.1007/s00405-013-2647-1] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2013] [Accepted: 07/20/2013] [Indexed: 11/30/2022]
Abstract
The objectives of this study were (1) to assess the protective role of NMDA antagonists against the ototoxic effects of aminoglycosides, (2) to provide any possible evidence between ototoxicity due to aminoglycosides and excitotoxicity. An animal experiment was conducted. Twenty-eight, 3-month-old female New Zealand rabbits, weighing 1,000-1,500 g, were studied prospectively for 28 days after intramuscular administration of amikacin (15 mg/kg/day divided into two equal doses) for 14 days. Twenty-one rabbits were categorized into three equal treatment groups and seven animals received no medication and served as the control group. The animals of A, B and C groups were injected, intramuscularly, with amikacin 15 mg/kg/day, divided into two equal doses every day for 14 days. Animals of group A received in parallel memantine (per os) and those of group B received p.o. the same volume of placebo solution. The rabbits of the third group (group C) received on the 15th day and every 2 days for the next 2 weeks, until the day 28, memantine of the same quantity as the members of group A. Differences in DPOAE amplitudes, and therefore in cochlear activity, between group A and group B were revealed. DPOAE amplitudes of group B were further reduced compared to the respective amplitudes in rabbits of group A. No improvement was observed in DPOAE measurements performed after the discontinuation of injections. The findings in group C should be examined separately. The measurements showed apparent reversal ototoxic effects in four of the animals. The development of aminoglycoside otoprotective strategies is a primary goal in ototoxicity research. The administration of NMDA antagonists has been shown to prevent, at least to some extent, toxic damage to hair cells in guinea pigs, treated with aminoglycoside antibiotics.
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Affiliation(s)
- Pavlos Pavlidis
- ENT Department, Katholisches Klinikum, Rudolf-Virchow-Str.7, 56073, Koblenz, Germany,
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Matt T, Ng CL, Lang K, Sha SH, Akbergenov R, Shcherbakov D, Meyer M, Duscha S, Xie J, Dubbaka SR, Perez-Fernandez D, Vasella A, Ramakrishnan V, Schacht J, Böttger EC. Dissociation of antibacterial activity and aminoglycoside ototoxicity in the 4-monosubstituted 2-deoxystreptamine apramycin. Proc Natl Acad Sci U S A 2012; 109:10984-9. [PMID: 22699498 PMCID: PMC3390888 DOI: 10.1073/pnas.1204073109] [Citation(s) in RCA: 152] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
Abstract
Aminoglycosides are potent antibacterials, but therapy is compromised by substantial toxicity causing, in particular, irreversible hearing loss. Aminoglycoside ototoxicity occurs both in a sporadic dose-dependent and in a genetically predisposed fashion. We recently have developed a mechanistic concept that postulates a key role for the mitochondrial ribosome (mitoribosome) in aminoglycoside ototoxicity. We now report on the surprising finding that apramycin, a structurally unique aminoglycoside licensed for veterinary use, shows little activity toward eukaryotic ribosomes, including hybrid ribosomes which were genetically engineered to carry the mitoribosomal aminoglycoside-susceptibility A1555G allele. In ex vivo cultures of cochlear explants and in the in vivo guinea pig model of chronic ototoxicity, apramycin causes only little hair cell damage and hearing loss but it is a potent antibacterial with good activity against a range of clinical pathogens, including multidrug-resistant Mycobacterium tuberculosis. These data provide proof of concept that antibacterial activity can be dissected from aminoglycoside ototoxicity. Together with 3D structures of apramycin-ribosome complexes at 3.5-Å resolution, our results provide a conceptual framework for further development of less toxic aminoglycosides by hypothesis-driven chemical synthesis.
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Affiliation(s)
- Tanja Matt
- Institut für Medizinische Mikrobiologie, Universität Zürich, 8006 Zürich, Switzerland
| | - Chyan Leong Ng
- Structural Studies Division, Medical Research Council (MRC) Laboratory of Molecular Biology, Cambridge CB2 0QH, United Kingdom
| | - Kathrin Lang
- Structural Studies Division, Medical Research Council (MRC) Laboratory of Molecular Biology, Cambridge CB2 0QH, United Kingdom
| | - Su-Hua Sha
- Kresge Hearing Research Institute, Department of Otolaryngology, Head and Neck Surgery, University of Michigan, Ann Arbor, MI 48109; and
| | - Rashid Akbergenov
- Institut für Medizinische Mikrobiologie, Universität Zürich, 8006 Zürich, Switzerland
| | - Dmitri Shcherbakov
- Institut für Medizinische Mikrobiologie, Universität Zürich, 8006 Zürich, Switzerland
| | - Martin Meyer
- Institut für Medizinische Mikrobiologie, Universität Zürich, 8006 Zürich, Switzerland
| | - Stefan Duscha
- Institut für Medizinische Mikrobiologie, Universität Zürich, 8006 Zürich, Switzerland
| | - Jing Xie
- Kresge Hearing Research Institute, Department of Otolaryngology, Head and Neck Surgery, University of Michigan, Ann Arbor, MI 48109; and
| | - Srinivas R. Dubbaka
- Laboratorium für Organische Chemie, Eidgenössische Technische Hochschule Zürich, 8093 Zürich, Switzerland
| | - Déborah Perez-Fernandez
- Laboratorium für Organische Chemie, Eidgenössische Technische Hochschule Zürich, 8093 Zürich, Switzerland
| | - Andrea Vasella
- Laboratorium für Organische Chemie, Eidgenössische Technische Hochschule Zürich, 8093 Zürich, Switzerland
| | - V. Ramakrishnan
- Structural Studies Division, Medical Research Council (MRC) Laboratory of Molecular Biology, Cambridge CB2 0QH, United Kingdom
| | - Jochen Schacht
- Kresge Hearing Research Institute, Department of Otolaryngology, Head and Neck Surgery, University of Michigan, Ann Arbor, MI 48109; and
| | - Erik C. Böttger
- Institut für Medizinische Mikrobiologie, Universität Zürich, 8006 Zürich, Switzerland
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Chen FQ, Hill K, Guan YJ, Schacht J, Sha SH. Activation of apoptotic pathways in the absence of cell death in an inner-ear immortomouse cell line. Hear Res 2011; 284:33-41. [PMID: 22240458 DOI: 10.1016/j.heares.2011.12.007] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/10/2010] [Revised: 12/17/2011] [Accepted: 12/19/2011] [Indexed: 01/21/2023]
Abstract
Aminoglycoside antibiotics and cisplatin (CDDP) are the major ototoxins of clinical medicine due to their capacity to cause significant and permanent hearing loss by targeting the mammalian sensory cells. Understanding the pathogenesis of damage is the first step in designing effective prevention of drug-induced hearing loss. In-vitro systems greatly enhance the efficiency of biochemical and molecular investigations through ease of access and manipulation. HEI-OC1, an inner ear cell line derived from the immortomouse, expresses markers for auditory sensory cells and, therefore, is a potential tool to study the ototoxic mechanisms of drugs like aminoglycoside antibiotics and CDDP. HEI-OC1 cells (and also HeLa cells) efficiently take up fluorescently tagged gentamicin and respond to drug treatment with changes in cell death and survival signaling pathways. Within hours, the c-Jun N-terminal kinase pathway and the transcription factor AP-1 were activated and at later times, the "executioner caspase", caspase-3. These responses were robust and elicited by both gentamicin and kanamycin. However, despite the initiation of apoptotic pathways and transient changes in nuclear morphology, cell death was not observed following aminoglycoside treatment, while administration of CDDP led to significant cell death as determined by flow cytometric measurements; β-galactosidase analysis ruled out senescence in gentamicin-treated cells. The ability to withstand treatment with aminoglycosides but not with CDDP suggests that this cell line might be helpful in providing some insight into the differential actions of the two ototoxic drugs.
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Affiliation(s)
- Fu-Quan Chen
- Department of Pathology and Laboratory Medicine, College of Medicine, Medical University of South Carolina, 39 Sabin Street, Charleston, SC 29425, USA
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Abstract
Aminoglycoside antibiotics rapidly enter and kill cochlear hair cells via apical mechanoelectrical transduction (MET) channels in vitro. In vivo, it remains unknown whether systemically-administered aminoglycosides cross the blood-labyrinth barrier into endolymph and enter hair cells. Here we show, for the first time, that systemic aminoglycosides are trafficked across the blood-endolymph barrier and preferentially enter hair cells across their apical membranes. This trafficking route is predominant compared to uptake via hair cell basolateral membranes during perilymph infusion.
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Affiliation(s)
- Hongzhe Li
- Oregon Hearing Research Center, Oregon Health & Science University, 3181 SW Sam Jackson Park Road, Portland, Oregon 97239
| | - Peter S. Steyger
- Oregon Hearing Research Center, Oregon Health & Science University, 3181 SW Sam Jackson Park Road, Portland, Oregon 97239
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Men M, Jiang L, Wang H, Liu Y, Hu Z, He C, Feng Y. Unique penetrance of hearing loss in a five-generation Chinese family with the mitochondrial 12S rRNA 1555A > G mutation. Acta Otolaryngol 2011; 131:970-5. [PMID: 21504270 DOI: 10.3109/00016489.2011.575794] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
CONCLUSIONS Analysis of the complete mtDNA genome and X-linkage of this five-generation Chinese family revealed that the 1555A > G mutation may lead to deafness. OBJECTIVES Mutations in mitochondrial DNA (mtDNA) have been found to be associated with sensorineural hearing loss. However, the variable clinical phenotype and incomplete penetrance of mtDNA 1555A > G-induced hearing loss complicate our understanding of this mutation. We aimed to identify whether nuclear genes, mitochondrial haplotypes/variants, and a possible threshold effect are involved in its manifestation in the pedigree. METHODS We performed clinical, genetic, and X-linkage analysis of a five-generation Chinese family in which all the affected individuals were male. RESULTS Clinical evaluation revealed that affected individuals with or without aminoglycoside exposure developed hearing loss extending gradually from 8000 Hz to 4000 Hz and then to 1000 Hz. Using X-linkage analysis and sequencing, we detected an identical homoplasmic 1555A > G mutation in nine individuals, and a previously unreported variant 14163C > T in mtDNA. The new variant 14163C > T coexisted with the 1555A > G mutation in six affected subjects of our pedigree. The previously unreported variant 14163C > T and aminoglycoside exposure may synergize the development of this deafness.
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Affiliation(s)
- Meichao Men
- Department of Otolaryngology, Head and Neck Surgery, Xiangya Hospital, Central South University, Changsha City, Hunan Province, China
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Zhao Z, Tong JW, Zhang JP, You XF, Jiang JD, Hu CQ. [Zebrafish model for the study on drug ototoxicity of aminoglycoside antibiotics]. Yao Xue Xue Bao 2011; 46:928-935. [PMID: 22007517] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Aminoglycoside antibiotics, due to their strong antibacterial effects and broad antimicrobial spectra, have been very commonly used in clinical practice in the past half century. However, aminoglycoside antibiotics manifest severe ototoxicity and nephrotoxicity, and are one of top factors in hearing loss. In this study, three members of the aminoglycoside antibiotics family, gentamycin, neomycin and streptomycin, were chosen as the representatives to be investigated for their toxicity to the embryonic development and the larva hair cells in zebrafish, and also to their target genes associated with hearing-related genes. The results showed that: (1) the lethal effect of all three drugs demonstrated a significant dependence on concentration, and the severity order of the lethal effect was streptomycin > neomycin > gentamycin; (2) all the three drugs caused the larva trunk bending in resting state at 5 dpf (day past fertilization), probably due to their ototoxicity in the physical imbalance and postural abnormalities; (3) impairment and reducing of the hair cells were observed in all three cases of drug treatment; (4) four genes, eya1, val, otx2 and dlx6a, which play an important role in the development of hearing organs, showed differential and significant decrease of gene expression in a drug concentration-dependent manner. This study for the first time reports the relevance between the expression of hearing genes and the three ototoxic antibiotics and also proved the feasibility of establishing a simple, accurate, intuitive and fast model with zebrafish for the detection of drug ototoxicity.
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Affiliation(s)
- Zhuang Zhao
- Institute of Medicinal Biotechnology, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing 100050, China
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Alharazneh A, Luk L, Huth M, Monfared A, Steyger PS, Cheng AG, Ricci AJ. Functional hair cell mechanotransducer channels are required for aminoglycoside ototoxicity. PLoS One 2011; 6:e22347. [PMID: 21818312 PMCID: PMC3144223 DOI: 10.1371/journal.pone.0022347] [Citation(s) in RCA: 184] [Impact Index Per Article: 14.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2011] [Accepted: 06/19/2011] [Indexed: 12/02/2022] Open
Abstract
Aminoglycosides (AG) are commonly prescribed antibiotics with potent bactericidal activities. One main side effect is permanent sensorineural hearing loss, induced by selective inner ear sensory hair cell death. Much work has focused on AG's initiating cell death processes, however, fewer studies exist defining mechanisms of AG uptake by hair cells. The current study investigated two proposed mechanisms of AG transport in mammalian hair cells: mechanotransducer (MET) channels and endocytosis. To study these two mechanisms, rat cochlear explants were cultured as whole organs in gentamicin-containing media. Two-photon imaging of Texas Red conjugated gentamicin (GTTR) uptake into live hair cells was rapid and selective. Hypocalcemia, which increases the open probability of MET channels, increased AG entry into hair cells. Three blockers of MET channels (curare, quinine, and amiloride) significantly reduced GTTR uptake, whereas the endocytosis inhibitor concanavalin A did not. Dynosore quenched the fluorescence of GTTR and could not be tested. Pharmacologic blockade of MET channels with curare or quinine, but not concanavalin A or dynosore, prevented hair cell loss when challenged with gentamicin for up to 96 hours. Taken together, data indicate that the patency of MET channels mediated AG entry into hair cells and its toxicity. Results suggest that limiting permeation of AGs through MET channel or preventing their entry into endolymph are potential therapeutic targets for preventing hair cell death and hearing loss.
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Affiliation(s)
- Abdelrahman Alharazneh
- Department of Otolaryngology-Head and Neck Surgery, Stanford University, Stanford, California, United States of America
- Department of Special Surgery, Mu'tah University, Alkarak, Jordan
| | - Lauren Luk
- Department of Otolaryngology-Head and Neck Surgery, Stanford University, Stanford, California, United States of America
| | - Markus Huth
- Department of Otolaryngology-Head and Neck Surgery, Stanford University, Stanford, California, United States of America
| | - Ashkan Monfared
- Department of Otolaryngology-Head and Neck Surgery, Stanford University, Stanford, California, United States of America
| | - Peter S. Steyger
- Department of Otolaryngology-Head and Neck Surgery, Oregon Health & Science University, Portland, Oregon, United States of America
| | - Alan G. Cheng
- Department of Otolaryngology-Head and Neck Surgery, Stanford University, Stanford, California, United States of America
- * E-mail: (AGC); (AJR)
| | - Anthony J. Ricci
- Department of Otolaryngology-Head and Neck Surgery, Stanford University, Stanford, California, United States of America
- Department of Molecular and Cellular Physiology, Stanford University, Stanford, California, United States of America
- * E-mail: (AGC); (AJR)
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Guan MX. Mitochondrial 12S rRNA mutations associated with aminoglycoside ototoxicity. Mitochondrion 2010; 11:237-45. [PMID: 21047563 DOI: 10.1016/j.mito.2010.10.006] [Citation(s) in RCA: 105] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2010] [Revised: 08/31/2010] [Accepted: 10/19/2010] [Indexed: 11/18/2022]
Abstract
The mitochondrial 12S rRNA is a hot spot for mutations associated with both aminoglycoside-induced and nonsyndromic hearing loss. Of those, the homoplasmic 1555A>G and 1494C>T mutations at the highly conserved decoding region of the 12S rRNA have been associated with hearing loss worldwide. In particular, these two mutations account for a significant number of cases of aminoglycoside ototoxicity. The 1555A>G or 1494C>T mutation is expected to form a novel 1494C-G1555 or 1494U-A1555 base-pair at the highly conserved A-site of 12S rRNA. These transitions make the human mitochondrial ribosomes more bacteria-like and alter binding sites for aminoglycosides. As a result, the exposure to aminoglycosides can induce or worsen hearing loss in individuals carrying one of these mutations. Biochemical characterization demonstrated an impairment of mitochondrial protein synthesis and subsequent defects in respiration in cells carrying the A1555G or 1494C>T mutation. Furthermore, a wide range of severity, age-at-onset and penetrance of hearing loss was observed within and among families carrying these mutations. Nuclear modifier genes, mitochondrial haplotypes and aminoglycosides should modulate the phenotypic manifestation of the 12S rRNA 1555A>G and 1494C>T mutations. Therefore, these data provide valuable information and technology: (1) to predict which individuals are at risk for ototoxicity; (2) to improve the safety of aminoglycoside antibiotic therapy; and (3) eventually to decrease the incidence of hearing loss.
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Affiliation(s)
- Min-Xin Guan
- Division of Human Genetics, Cincinnati Children's Hospital Medical Center, Cincinnati, OH 45229-3039, USA.
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Abstract
Although aminoglycosides have been used as antibacterials for decades, their use has been hindered by their inherent toxicity and the resistance that has emerged to these compounds. It seems that such issues have relegated a formerly front-line class of antimicrobials to the proverbial back shelf. However, recent advances have demonstrated that novel aminoglycosides have a potential to overcome resistance as well as to be used to treat HIV-1 and even human genetic disorders, with abrogated toxicity. It is not the end for aminoglycosides, but rather, the challenges faced by researchers have led to ingenuity and a change in how we view this class of compounds, a renaissance.
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Affiliation(s)
- Jacob L Houghton
- Department of Medicinal Chemistry in the College of Pharmacy, University of Michigan, 210 Washtenaw Avenue, Ann Arbor, MI 48109, USA
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Froehlicher M, Liedtke A, Groh KJ, Neuhauss SCF, Segner H, Eggen RIL. Zebrafish (Danio rerio) neuromast: promising biological endpoint linking developmental and toxicological studies. Aquat Toxicol 2009; 95:307-19. [PMID: 19467721 DOI: 10.1016/j.aquatox.2009.04.007] [Citation(s) in RCA: 85] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/19/2008] [Revised: 04/16/2009] [Accepted: 04/18/2009] [Indexed: 05/20/2023]
Abstract
Aquatic toxicology is facing the challenge to assess the impact of complex mixtures of compounds on diverse biological endpoints. So far, ecotoxicology focuses mainly on apical endpoints such as growth, lethality and reproduction, but does not consider sublethal toxic effects that may indirectly cause ecological effects. One such sublethal effect is toxicant-induced impairment of neurosensory functions which will affect important behavioural traits of exposed organisms. Here, we critically review the mechanosensory lateral line (LL) system of zebrafish as a model to screen for chemical effects on neurosensory function of fish in particular and vertebrates in general. The LL system consists of so-called neuromasts, composed of centrally located sensory hair cells, and surrounding supporting cells. The function of neuromasts is the detection of water movements that is essential for the fish's ability to detect prey, to escape predator, to socially interact or to show rheotactic behaviour. Recent advances in the study of these organs provided researchers with a broad area of molecular tools for easy and rapid detection of neuromasts dysfunction and/or disturbed development. Further, genes involved in neuromasts differentiation have been identified using auditory/mechanosensory mutants and morphants. A number of environmental toxicants including metals and pharmaceuticals have been shown to affect neuromasts development and/or function. The use of the LL organ for toxicological studies offers the advantage to integrate the available profound knowledge on developmental biology of the neuromasts with the study of chemical toxicity. This combination may provide a powerful tool in environmental risk assessment.
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Affiliation(s)
- Mirjam Froehlicher
- Eawag, Swiss Federal Institute of Aquatic Science and Technology, 8600 Dübendorf, Switzerland
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Qian Y, Guan MX. Interaction of aminoglycosides with human mitochondrial 12S rRNA carrying the deafness-associated mutation. Antimicrob Agents Chemother 2009; 53:4612-8. [PMID: 19687236 PMCID: PMC2772318 DOI: 10.1128/aac.00965-08] [Citation(s) in RCA: 78] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2008] [Revised: 11/12/2008] [Accepted: 08/12/2009] [Indexed: 11/20/2022] Open
Abstract
The mitochondrial 12S rRNA A1555G mutation is one of the important causes of aminoglycoside-induced and nonsyndromic hearing loss. Here we employed an RNA-directed chemical-modification approach to understanding the pathogenesis of aminoglycoside-induced hearing loss. The patterns of chemical modification of RNA oligonucleotides carrying the A1555G mutation by dimethyl sulfate (DMS) were distinct from those of the RNA oligonucleotides carrying wild-type sequence in the presence of aminoglycosides. In the RNA analogue carrying the A1555G mutation, reduced reactivity to DMS occurred in base G1555 as well as in bases C1556 and A1553 in the presence of paromomycin, neomycin, gentamicin, kanamycin, tobramycin, or streptomycin. In particular, base G1555 exhibited marked but similar levels of protection in the presence of 0.1 microM to 100 microM neomycin, gentamicin, or kanamycin. In contrast, the levels of protection in base G1555 appeared to be correlated with the concentration of paromycin, tobramycin, or streptomycin. Furthermore, increasing reactivities to DMS in the presence of these aminoglycosides were observed for bases A1492, C1493, C1494, and A1557 in the RNA analogue carrying the A1555G mutation. These data suggested that the A1555G mutation altered the binding properties of aminoglycosides at the A site of 12S rRNA and led to local conformational changes in 12S rRNA carrying the A1555G mutation. The interaction between aminoglycosides and 12S rRNA carrying the A1555G mutation provides new insight into the pathogenesis of aminoglycoside ototoxicity.
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Affiliation(s)
- Yaping Qian
- Division of Human Genetics, Cincinnati Children's Hospital Medical Center, Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, Ohio
| | - Min-Xin Guan
- Division of Human Genetics, Cincinnati Children's Hospital Medical Center, Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, Ohio
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Zhu Y, Li Q, Chen Z, Kun Y, Liu L, Liu X, Yuan H, Zhai S, Han D, Dai P. Mitochondrial haplotype and phenotype of 13 Chinese families may suggest multi-original evolution of mitochondrial C1494T mutation. Mitochondrion 2009; 9:418-28. [PMID: 19682603 DOI: 10.1016/j.mito.2009.07.006] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2009] [Revised: 05/09/2009] [Accepted: 07/29/2009] [Indexed: 11/18/2022]
Abstract
Mutations in mitochondrial DNA (mtDNA) are associated with sensorineural hearing loss. In this study, we traced the origin of the 12S rRNA C1494T mutation through analysis of the clinical, genetic, and molecular characteristics of 13 Han Chinese pedigrees with aminoglycoside-induced and non-syndromic bilateral hearing loss that were selected by C1494T screening in 3133 subjects with non-syndromic hearing impairment from 27 regions of China (13/3133). Clinical evaluation revealed the variable phenotypes of hearing impairment including severity, age-of-onset, and audiometric configuration in these subjects. Through the whole mitochondrial genome DNA sequence analysis, we identified two evolutionarily conservative variants in protein-coding genes: tRNA(Ala) T 5628C and tRNA(Tyr) A5836G mutations. However, the pedigrees with these mutations did not have a higher or lower penetrance of deafness than in other pedigrees. These results suggested that both T 5628C and A5836G mutations might not significantly modify the manifestation of the C1494T mutation. Sequencing analysis of the whole mitochondrial genome of the probands showed that 13 pedigrees from seven different provinces were classified into 10 haplogroups by the distinct sets of mtDNA polymorphisms, including haplogroups A, B, D, D4, D4b2, F1, M, M7c, N9a1, and H2b. This result suggested that the C1494T mutation occurred sporadically with multi-origins through the evolution of the mtDNA in China, and these mtDNA haplogroup-specific variants may not play an important role in the phenotypic expression of the C1494T mutation in these Chinese families with different penetrance of hearing loss. In addition, the lack of a significant mutation in the GJB2 gene ruled out the possible involvement of GJB2 in the phenotypic expression of the C1494T mutation in those affected subjects. Therefore, the aminoglycosides is solo well-established factor to contribute to the deafness manifestation of the C1494T mutation, and prevention by avoiding the administration of aminoglycosides in individuals carrying C1494T mutation is the most effective way to protect their vulnerability to deafness.
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Affiliation(s)
- Yuhua Zhu
- Department of Otolaryngology, Chinese PLA General Hospital, Beijing, China
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Nykjaer A, Schambye H, Pedersen AH, Nielsen H. Assessing low-dose gentamicin-induced kidney injury in rats by analysis of urine. J Pharmacol Toxicol Methods 2009; 60:316-20. [PMID: 19632345 DOI: 10.1016/j.vascn.2009.07.006] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2009] [Accepted: 07/17/2009] [Indexed: 11/18/2022]
Abstract
INTRODUCTION Gentamicin is an important aminoglycoside antibiotic used in clinics to combat infections from especially gram negative bacteria. A frequent side-effect of aminoglycoside antibiotics is a kidney injury consisting of necrosis of proximal tubular cells. It is important both in clinics and in research directed to eliminate or ameliorate this side-effect that a method is available for detection of injury at an early stage. METHODS We have therefore compared the sensitivity of four methods currently used in animal models to assess kidney injury induced by aminoglycoside antibiotics by applying them to the analysis of urine from male rats treated with low doses of gentamicin. RESULTS Excretion of phospholipids was significantly increased in contrast to excretion of N-acetyl-beta-glucosaminidase (NAG), neutrophil gelatinase-associated lipocalin (NGAL) and protein. Assessment of phospholipiduria thus is the more sensitive noninvasive way to monitor initial renal injury induced by aminoglycoside antibiotics. A protocol is given for the serial analysis of urinary phospholipids allowing a considerable number of determinations to be carried out in the course of 2-3 days. DISCUSSION It is well known that all four considered methods do detect kidney damage induced in rats by high gentamicin doses far above doses used in clinics. The present investigation shows that only the analysis of the urinary phospholipids will detect damage induced by low doses of gentamicin. The method is relevant for animal model studies but will require considerable and innovative development for use in clinics.
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Affiliation(s)
- Anders Nykjaer
- Department of Medical Biochemistry, Aarhus University, DK 8000 Aarhus C, Denmark
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Yamaguchi Y, Usui N, Dobashi N, Yano S, Yahagi Y, Takei Y, Sugiyama K, Ogasawara Y, Saito T, Minami J, Kobayashi T, Katsube A, Kamiyama Y, Machishima T, Morikawa N, Otsubo H, Kaito K, Asai O, Aiba K. Gemtuzumab ozogamicin (GO) in relapsed/refractory patients with acute myeloid leukemia. Gan To Kagaku Ryoho 2009; 36:1105-1109. [PMID: 19620797] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
OBJECTIVE Gemtuzumab ozogamicin (GO) is a humanized anti-CD33 antibody, linked to calicheamicin, which has been approved in Japan recently. We conducted to evaluate the efficacy and toxicity of GO in our patients with relapsed or refractory AML retrospectively. PATIENTS AND METHODS Data were collected between March 1, 2000, and March 1, 2006, on 10 patients with relapsed or refractory AML(excluding FAB: M3). Scheduled treatment was two doses of GO monotherapy, 14-28 days apart. RESULTS Of the 10 assessable patients, two patients achieved CR. CR duration of one patient lasted for 52 months with post-remission treatment. Grade 4 neutropenia occurred in 9 patients, and the incidence of grade 3 or 4 thrombocytopenia was 100%, with no severe bleeding events. Two patients developed infusion-related adverse events that included grade 3 allergic reaction with shock status. Liver damage (grade 3 or 4) were observed in 40% of patients after GO treatment. No patient developed hepatic veno-occlusive disease including 2 patients who underwent HSCT. CONCLUSION GO is a valuable new treatment option for relapsed or refractory AML patients, however, the benefit from single agent appears insufficient. On going clinical trials including combination with other antileukemic agents might better define the role of GO.
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Affiliation(s)
- Yuko Yamaguchi
- Department of Oncology and Hematology, Jikei University School of Medicine, Komae-shi, Tokyo, Japan
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Taleb M, Brandon CS, Lee FS, Harris KC, Dillmann WH, Cunningham LL. Hsp70 inhibits aminoglycoside-induced hearing loss and cochlear hair cell death. Cell Stress Chaperones 2009; 14:427-37. [PMID: 19145477 PMCID: PMC2728278 DOI: 10.1007/s12192-008-0097-2] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2008] [Revised: 12/10/2008] [Accepted: 12/16/2008] [Indexed: 10/21/2022] Open
Abstract
Sensory hair cells of the inner ear are sensitive to death from aging, noise trauma, and ototoxic drugs. Ototoxic drugs include the aminoglycoside antibiotics and the antineoplastic agent cisplatin. Exposure to aminoglycosides results in hair cell death that is mediated by specific apoptotic proteins, including c-Jun N-terminal kinase (JNK) and caspases. Induction of heat shock proteins (Hsps) can inhibit JNK- and caspase-dependent apoptosis in a variety of systems. We have previously shown that heat shock results in robust upregulation of Hsps in the hair cells of the adult mouse utricle in vitro. In addition, heat shock results in significant inhibition of both cisplatin- and aminoglycoside-induced hair cell death. In this system, Hsp70 is the most strongly induced Hsp, which is upregulated over 250-fold at the level of mRNA 2 h after heat shock. Hsp70 overexpression inhibits aminoglycoside-induced hair cell death in vitro. In this study, we utilized Hsp70-overexpressing mice to determine whether Hsp70 is protective in vivo. Both Hsp70-overexpressing mice and their wild-type littermates were treated with systemic kanamycin (700 mg/kg body weight) twice daily for 14 days. While kanamycin treatment resulted in significant hearing loss and hair cell death in wild-type mice, Hsp70-overexpressing mice were significantly protected against aminoglycoside-induced hearing loss and hair cell death. These data indicate that Hsp70 is protective against aminoglycoside-induced ototoxicity in vivo.
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Affiliation(s)
- Mona Taleb
- Department of Pathology and Laboratory Medicine, Medical University of South Carolina, 171 Ashley Avenue, MSC 908, Charleston, SC 29425 USA
| | - Carlene S. Brandon
- Department of Pathology and Laboratory Medicine, Medical University of South Carolina, 171 Ashley Avenue, MSC 908, Charleston, SC 29425 USA
| | - Fu-Shing Lee
- Department of Otolaryngology–Head and Neck Surgery, Medical University of South Carolina, Charleston, SC 29425 USA
| | - Kelly C. Harris
- Department of Otolaryngology–Head and Neck Surgery, Medical University of South Carolina, Charleston, SC 29425 USA
| | - Wolfgang H. Dillmann
- Department of Endocrinology, School of Medicine, University of California, San Diego, La Jolla, CA 92093 USA
| | - Lisa L. Cunningham
- Department of Pathology and Laboratory Medicine, Medical University of South Carolina, 171 Ashley Avenue, MSC 908, Charleston, SC 29425 USA
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Bushma KM, Bushma MI. [Individual activity of renal enzymes in the susceptibility of hydronephrotic rabbits to aminoglycoside (gentamicin) nephrotoxicity]. Eksp Klin Farmakol 2009; 72:55-59. [PMID: 19441732] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
A correlation between the individual features of the activity of renal enzymes and the expression of aminoglycoside (gentamicin) induced nephrotoxicity is established in hydronephrotic rabbits. The level of gentamicin-induced damage of the kidney is more significant in rabbits with initially (prior to gentamicin administration) increased activity of lactate dehydrogenase, decreased activity of succinate dehydrogenase and acid phosphatase, and low content of ribonucleoproteins.
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Cotanche DA. Genetic and pharmacological intervention for treatment/prevention of hearing loss. J Commun Disord 2008; 41:421-443. [PMID: 18455177 PMCID: PMC2574670 DOI: 10.1016/j.jcomdis.2008.03.004] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/04/2008] [Accepted: 03/12/2008] [Indexed: 05/26/2023]
Abstract
UNLABELLED Twenty years ago it was first demonstrated that birds could regenerate their cochlear hair cells following noise damage or aminoglycoside treatment. An understanding of how this structural and functional regeneration occurred might lead to the development of therapies for treatment of sensorineural hearing loss in humans. Recent experiments have demonstrated that noise exposure and aminoglycoside treatment lead to apoptosis of the hair cells. In birds, this programmed cell death induces the adjacent supporting cells to undergo regeneration to replace the lost hair cells. Although hair cells in the mammalian cochlea undergo apoptosis in response to noise damage and ototoxic drug treatment, the supporting cells do not possess the ability to undergo regeneration. However, current experiments on genetic manipulation, gene therapy, and stem cell transplantation suggest that regeneration in the mammalian cochlea may eventually be possible and may 1 day provide a therapeutic tool for hearing loss in humans. LEARNING OUTCOMES The reader should be able to: (1) Describe the anatomy of the avian and mammalian cochlea, identify the individual cell types in the organ of Corti, and distinguish major features that participate in hearing function, (2) Demonstrate a knowledge of how sound damage and aminoglycoside poisoning induce apoptosis of hair cells in the cochlea, (3) Define how hair cell loss in the avian cochlea leads to regeneration of new hair cells and distinguish this from the mammalian cochlea where there is no regeneration following damage, and (4) Interpret the potential for new approaches, such as genetic manipulation, gene therapy and stem cell transplantation, could provide a therapeutic approach to hair cell loss in the mammalian cochlea.
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MESH Headings
- Aminoglycosides/toxicity
- Animals
- Apoptosis/drug effects
- Apoptosis/genetics
- Apoptosis/physiology
- Birds
- Cell Proliferation/drug effects
- Genetic Therapy
- Guinea Pigs
- Hair Cells, Auditory/drug effects
- Hair Cells, Auditory/pathology
- Hair Cells, Auditory/physiology
- Hearing Loss, Noise-Induced/pathology
- Hearing Loss, Noise-Induced/physiopathology
- Hearing Loss, Noise-Induced/therapy
- Hearing Loss, Sensorineural/pathology
- Hearing Loss, Sensorineural/physiopathology
- Hearing Loss, Sensorineural/therapy
- Humans
- Mice
- Mice, Knockout
- Microscopy, Confocal
- Nerve Regeneration/drug effects
- Nerve Regeneration/genetics
- Nerve Regeneration/physiology
- Organ of Corti/drug effects
- Organ of Corti/pathology
- Organ of Corti/physiopathology
- Stem Cell Transplantation
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Affiliation(s)
- Douglas A Cotanche
- Laboratory of Cellular and Molecular Hearing Research, Department of Otolaryngology, Children's Hospital Boston, Boston, MA, USA.
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Barcia-Macay M, Mouaden F, Mingeot-Leclercq MP, Tulkens PM, Van Bambeke F. Cellular pharmacokinetics of telavancin, a novel lipoglycopeptide antibiotic, and analysis of lysosomal changes in cultured eukaryotic cells (J774 mouse macrophages and rat embryonic fibroblasts). J Antimicrob Chemother 2008; 61:1288-94. [PMID: 18375379 PMCID: PMC2386079 DOI: 10.1093/jac/dkn120] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023] Open
Abstract
Background Telavancin is a lipoglycopeptide with multiple mechanisms of action that include membrane-destabilizing effects towards bacterial cells. It shows bactericidal activity against forms of Staphylococcus aureus (phagolysosomal infection) with different resistance phenotypes [methicillin-resistant S. aureus, vancomycin-intermediate S. aureus or vancomycin-resistant S. aureus]. We examine here the uptake, efflux and intracellular distribution of telavancin in eukaryotic cells as well as its potential to induce lysosomal changes (in comparison with vancomycin and oritavancin). Methods J774 macrophages and rat embryo fibroblasts were exposed for up to 24 and 72 h to telavancin (5–90 mg/L). The following studies were performed: measurement of 14C-labelled telavancin cellular uptake and subcellular distribution (cell fractionation), determination of pericellular membrane integrity (lactate dehydrogenase release), electron microscopy with morphometric analysis of changes in lysosome size and determination of total phospholipid and cholesterol content. Results The uptake of telavancin proceeded linearly as a function of time and concentration in both cell types (clearance rate of ∼10 mL/g of protein/h). Efflux (macrophages) was ∼5.7-fold slower. Telavancin subcellular distribution was superimposable on that of a lysosomal marker (N-acetyl-β-hexosaminidase). It did not cause an increase in the release of lactate dehydrogenase and did not induce significant increases in total phospholipid or cholesterol content. It caused only mild morphological lysosomal alterations (similar to vancomycin and much less than oritavancin by morphometric analysis). Conclusions Telavancin is taken up by eukaryotic cells and localizes in lysosomes, causing mild morphological alterations without evidence of lipid metabolism alterations. These data support our observations that telavancin is active against intracellular S. aureus.
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45
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Matseliukh BP. [Recent achievements of the Department of Genetics of Microorganisms]. Mikrobiol Z 2008; 70:63-68. [PMID: 18663923] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
The main achievements of the Department of Genetics of Microorganisms during the recent 7 years in the fundamental and applied researches are presented in this review of literature.
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46
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Owens KN, Santos F, Roberts B, Linbo T, Coffin AB, Knisely AJ, Simon JA, Rubel EW, Raible DW. Identification of genetic and chemical modulators of zebrafish mechanosensory hair cell death. PLoS Genet 2008; 4:e1000020. [PMID: 18454195 PMCID: PMC2265478 DOI: 10.1371/journal.pgen.1000020] [Citation(s) in RCA: 157] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2007] [Accepted: 01/10/2008] [Indexed: 11/18/2022] Open
Abstract
Inner ear sensory hair cell death is observed in the majority of hearing and balance disorders, affecting the health of more than 600 million people worldwide. While normal aging is the single greatest contributor, exposure to environmental toxins and therapeutic drugs such as aminoglycoside antibiotics and antineoplastic agents are significant contributors. Genetic variation contributes markedly to differences in normal disease progression during aging and in susceptibility to ototoxic agents. Using the lateral line system of larval zebrafish, we developed an in vivo drug toxicity interaction screen to uncover genetic modulators of antibiotic-induced hair cell death and to identify compounds that confer protection. We have identified 5 mutations that modulate aminoglycoside susceptibility. Further characterization and identification of one protective mutant, sentinel (snl), revealed a novel conserved vertebrate gene. A similar screen identified a new class of drug-like small molecules, benzothiophene carboxamides, that prevent aminoglycoside-induced hair cell death in zebrafish and in mammals. Testing for interaction with the sentinel mutation suggests that the gene and compounds may operate in different pathways. The combination of chemical screening with traditional genetic approaches is a new strategy for identifying drugs and drug targets to attenuate hearing and balance disorders. Loss of sensory hair cells in the inner ear is observed in the majority of hearing and balance disorders, affecting the health of more than 600 million people worldwide. Exposure to environmental toxins and certain pharmaceutical drugs such as aminoglycoside antibiotics and some cancer chemotherapy agents account for many of these hearing and balance problems. Variation in the genetic makeup between individuals plays a major role in establishing differences in susceptibility to environmental agents that damage the inner ear. Using zebrafish larvae, we developed a screen to uncover genes leading to differences in antibiotic-induced death of hair cells and to identify compounds that protect hair cells from damage. The combination of chemical screening with traditional genetic approaches offers a new strategy for identifying drugs and drug targets to attenuate hearing and balance disorders.
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MESH Headings
- Aminoglycosides/antagonists & inhibitors
- Aminoglycosides/toxicity
- Animals
- Base Sequence
- Cell Death/drug effects
- Cell Death/genetics
- Cisplatin/toxicity
- Codon, Terminator/genetics
- DNA Primers/genetics
- DNA, Complementary/genetics
- Drug Evaluation, Preclinical
- Epistasis, Genetic
- Hair Cells, Auditory, Inner/cytology
- Hair Cells, Auditory, Inner/drug effects
- Hair Cells, Auditory, Inner/physiology
- Hearing Loss/etiology
- Hearing Loss/genetics
- Hearing Loss/prevention & control
- Humans
- Mice
- Neomycin/antagonists & inhibitors
- Neomycin/toxicity
- Point Mutation
- Saccule and Utricle/drug effects
- Saccule and Utricle/pathology
- Thiophenes/chemistry
- Thiophenes/pharmacology
- Zebrafish/anatomy & histology
- Zebrafish/genetics
- Zebrafish/physiology
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Affiliation(s)
- Kelly N. Owens
- Department of Biological Structure, University of Washington, Seattle, Washington, United States of America
- Virginia Merrill Bloedel Hearing Research Center, University of Washington, Seattle, Washington, United States of America
- Department of Otolaryngology—Head and Neck Surgery, University of Washington, Seattle, Washington, United States of America
| | - Felipe Santos
- Virginia Merrill Bloedel Hearing Research Center, University of Washington, Seattle, Washington, United States of America
- Department of Otolaryngology—Head and Neck Surgery, University of Washington, Seattle, Washington, United States of America
| | - Brock Roberts
- Department of Biological Structure, University of Washington, Seattle, Washington, United States of America
| | - Tor Linbo
- Department of Biological Structure, University of Washington, Seattle, Washington, United States of America
| | - Allison B. Coffin
- Virginia Merrill Bloedel Hearing Research Center, University of Washington, Seattle, Washington, United States of America
- Department of Otolaryngology—Head and Neck Surgery, University of Washington, Seattle, Washington, United States of America
| | - Anna J. Knisely
- Virginia Merrill Bloedel Hearing Research Center, University of Washington, Seattle, Washington, United States of America
- Department of Otolaryngology—Head and Neck Surgery, University of Washington, Seattle, Washington, United States of America
| | - Julian A. Simon
- Fred Hutchinson Cancer Research Center, Seattle, Washington, United States of America
| | - Edwin W. Rubel
- Virginia Merrill Bloedel Hearing Research Center, University of Washington, Seattle, Washington, United States of America
- Department of Otolaryngology—Head and Neck Surgery, University of Washington, Seattle, Washington, United States of America
- Department of Physiology and Biophysics, University of Washington, Seattle, Washington, United States of America
| | - David W. Raible
- Department of Biological Structure, University of Washington, Seattle, Washington, United States of America
- Virginia Merrill Bloedel Hearing Research Center, University of Washington, Seattle, Washington, United States of America
- * E-mail:
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Chen J, Yang L, Yang A, Zhu Y, Zhao J, Sun D, Tao Z, Tang X, Wang J, Wang X, Lan J, Li W, Wu F, Yuan Q, Feng J, Wu C, Liao Z, Li Z, Greinwald JH, Lu J, Guan MX. Maternally inherited aminoglycoside-induced and nonsyndromic hearing loss is associated with the 12S rRNA C1494T mutation in three Han Chinese pedigrees. Gene 2007; 401:4-11. [PMID: 17698299 PMCID: PMC2014725 DOI: 10.1016/j.gene.2007.06.009] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2007] [Revised: 06/04/2007] [Accepted: 06/06/2007] [Indexed: 11/24/2022]
Abstract
We report here the clinical, genetic and molecular characterization of three Han Chinese pedigrees with maternally transmitted aminoglycoside-induced and nonsyndromic bilateral hearing loss. Clinical evaluation revealed the wide range of severity, age-at-onset and audiometric configuration of hearing impairment in matrilineal relatives in these families. The penetrances of hearing loss in these pedigrees were 28%, 20%, and 15%, with an average of 21%, when aminoglycoside-induced deafness was included. When the effect of aminoglycosides was excluded, the penetrances of hearing loss in these seven pedigrees were 21%, 13% and 8%, with an average of 14%. Sequence analysis of the complete mitochondrial genomes in these pedigrees showed the presence of the deafness-associated 12S rRNA C1494T mutation, in addition to distinct sets of mtDNA polymorphism belonging to Eastern Asian haplogroups F1a1, F1a1 and D5a2, respectively. This suggested that the C1494T mutation occurred sporadically and multiplied through evolution of the mtDNA. The absence of functionally significant mutations in tRNA and rRNAs or secondary LHON mutations in their mtDNA suggests that these mtDNA haplogroup-specific variants may not play an important role in the phenotypic expression of the C1494T mutation in those Chinese families. In addition, the lack of significant mutation in the GJB2 gene ruled out the possible involvement of GJB2 in the phenotypic expression of the C1494T mutation in those affected subjects. However, aminoglycosides and other nuclear modifier genes play a modifying role in the phenotypic manifestation of the C1494T mutation in these Chinese families.
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Affiliation(s)
- Jianfu Chen
- Department of Otolaryngology, the First Affiliated Hospital, Wenzhou Medical College, Wenzhou, Zhejiang, China
- Zhejiang Provincial Key Laboratory of Medical Genetics, School of Life Sciences, Wenzhou Medical College, Wenzhou, Zhejiang, China
| | - Li Yang
- Division of Human Genetics and Center for Hearing and Deafness Research, Cincinnati Children’s Hospital Medical Center, Cincinnati, Ohio, USA
| | - Aifeng Yang
- Zhejiang Provincial Key Laboratory of Medical Genetics, School of Life Sciences, Wenzhou Medical College, Wenzhou, Zhejiang, China
| | - Yi Zhu
- Department of Otolaryngology, the First Affiliated Hospital, Wenzhou Medical College, Wenzhou, Zhejiang, China
- Zhejiang Provincial Key Laboratory of Medical Genetics, School of Life Sciences, Wenzhou Medical College, Wenzhou, Zhejiang, China
| | - Jianyue Zhao
- Zhejiang Provincial Key Laboratory of Medical Genetics, School of Life Sciences, Wenzhou Medical College, Wenzhou, Zhejiang, China
| | - Dongmei Sun
- Zhejiang Provincial Key Laboratory of Medical Genetics, School of Life Sciences, Wenzhou Medical College, Wenzhou, Zhejiang, China
| | - Zhihua Tao
- Department of Laboratory Medicine, the First Affiliated Hospital, Wenzhou Medical College, Wenzhou, Zhejiang, China
| | - Xiaowen Tang
- Zhejiang Provincial Key Laboratory of Medical Genetics, School of Life Sciences, Wenzhou Medical College, Wenzhou, Zhejiang, China
| | - Jindan Wang
- Zhejiang Provincial Key Laboratory of Medical Genetics, School of Life Sciences, Wenzhou Medical College, Wenzhou, Zhejiang, China
| | - Xinjian Wang
- Division of Human Genetics and Center for Hearing and Deafness Research, Cincinnati Children’s Hospital Medical Center, Cincinnati, Ohio, USA
| | - Jinshan Lan
- Department of Otolaryngology, Quzhou People’s Hospital, Quzhou, Zhejiang, China
| | - Weixing Li
- Zhejiang Provincial Key Laboratory of Medical Genetics, School of Life Sciences, Wenzhou Medical College, Wenzhou, Zhejiang, China
- Department of Laboratory Medicine, Zhejiang Provincial People’s Hospital, Hangzhou, Zhejiang, 310014, China
| | - Fangli Wu
- Zhejiang Provincial Key Laboratory of Medical Genetics, School of Life Sciences, Wenzhou Medical College, Wenzhou, Zhejiang, China
- Department of Laboratory Medicine, the Affiliated Hospital, Shaoxing University College of Medicine, Shaoxing, Zhejiang, China
| | - Qian Yuan
- Department of Laboratory Medicine, the First Affiliated Hospital, Wenzhou Medical College, Wenzhou, Zhejiang, China
| | - Jinbao Feng
- Quzhou Special Education School, Quzhou, Zhejiang 324000, China
| | - Chunli Wu
- Quzhou Special Education School, Quzhou, Zhejiang 324000, China
| | - Zhisu Liao
- Department of Otolaryngology, the First Affiliated Hospital, Wenzhou Medical College, Wenzhou, Zhejiang, China
| | - Zhiyuan Li
- Department of Otolaryngology, the First Affiliated Hospital, Wenzhou Medical College, Wenzhou, Zhejiang, China
| | - John H. Greinwald
- Division of Otolaryngology, Cincinnati Children’s Hospital Medical Center, Cincinnati, Ohio, USA
- Deparment of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, Ohio, USA
| | - Jianxin Lu
- Zhejiang Provincial Key Laboratory of Medical Genetics, School of Life Sciences, Wenzhou Medical College, Wenzhou, Zhejiang, China
| | - Min-Xin Guan
- Zhejiang Provincial Key Laboratory of Medical Genetics, School of Life Sciences, Wenzhou Medical College, Wenzhou, Zhejiang, China
- Division of Human Genetics and Center for Hearing and Deafness Research, Cincinnati Children’s Hospital Medical Center, Cincinnati, Ohio, USA
- Deparment of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, Ohio, USA
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Konopska B, Warwas M. [Molecular aspects of aminoglycoside nephrotoxicity]. POSTEP HIG MED DOSW 2007; 61:511-8. [PMID: 17909519] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2007] [Accepted: 09/11/2007] [Indexed: 05/17/2023] Open
Abstract
Aminoglycosides are potent bactericidal antibiotics particularly active against aerobic Gram-negative bacteria. This review focuses on the recent concept of a molecular understanding of aminoglycoside-induced nephrotoxicity. As receptor-mediated endocytosis plays an important role in the accumulation of aminoglycosides in renal proximal tubules, the biochemical properties of the two main receptors, megalin and cubilin, involved in this process are described. Literature data on megalin and acidic phospholipids as potential targets for preventing aminoglycoside-induced nephrotoxicity are also presented.
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Affiliation(s)
- Bogusława Konopska
- Katedra i Zakład Biochemii Farmaceutycznej Akademii Medycznej we Wrocławiu
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49
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Abstract
Few investigators have examined the circadian variation in the symptom intensity of infectious diseases. Seasonal patterns in a variety of infectious are well know. Less appreciated are the circadian patterns in the symptom expression of infections. Studies indicate that fever which accompanies the common cold peaks at 4 p.m., and this is in agreement with other studies indicating that the elevation of body temperature, fever, due to bacterial infections is higher in the evening while that due to viral infections is more likely in the morning. Animal and human studies reveal also administration-time-dependent differences in the pharmacokinetics and toxicity of antimicrobial agents. This is particularly true for the aminoglycosides, as their nephrotoxicity is greatest when administered during the resting period of laboratory animals and human beings. Food intake and low urinary pH has been found to be protective of the toxicity of aminoglycosides at this time of the day. Knowledge of the administration-time-dependence of aminoglycosides and the underlying mechanisms can be used to develop once-a-day formulations that are significantly less toxic, in particular to the kidney, in patients who require around-the-clock antimicrobial therapy.
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Affiliation(s)
- Denis Beauchamp
- Research Center on Infectious Diseases and Centre Hospitalier Universitaire de Québec, Pavilion CHUL, Canada
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Liu YH, Ke XM, Qin Y, Gu ZP, Xiao SF. Adeno-associated virus-mediated Bcl-xL prevents aminoglycoside-induced hearing loss in mice. Chin Med J (Engl) 2007; 120:1236-40. [PMID: 17697574] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/16/2023] Open
Abstract
BACKGROUND Recent studies showed that aminoglycosides destroyed the cochlear cells and induced ototoxicity by producing reactive oxygen species, including free radicals in the mitochondria, damaging the membrane of mitochondria and resulting in apoptotic cell death. Bcl-x(L) is a well characterized anti-apoptotic member of the Bcl-2 family. The aim of this study was to determine the potential cochlear protective effect of Bcl-x(L) as a therapeutic agent in the murine model of aminoglycoside ototoxicity. METHODS Serotype 2 of adeno-associated virus (AAV2) as a vector encoding the mouse Bcl-x(L) gene was injected into mice cochleae prior to injection of kanamycin. Bcl-x(L) expression in vitro and in vivo was examined with Western blotting and immunohistochemistry separately. Cochlear dissection and auditory steady state responses were checked to evaluate the cochlear structure and function. RESULTS The animals in the AAV2-Bcl-x(L)/kanamycin group displayed better auditory steady state responses hearing thresholds and cochlear structure than those in the artificial perilymph/kanamycin or AAV2-enhanced humanized green fluorescent protein/kanamycin control group at all tested frequencies. The auditory steady state responses hearing thresholds and cochlear structure in the inoculated side were better than that in the contralateral side. CONCLUSIONS AAV2-Bcl-x(L) afforded significant preservation of the cochlear hair cells against ototoxic insults and protected the cochlear function. AAV2-mediated Bcl-x(L) might be an approach with respect to potential therapeutic application in the cochlear degeneration.
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Affiliation(s)
- Yu-He Liu
- Department of Otolaryngology, Head and Neck Surgery, Peking University First Hospital, Beijing 100034, China.
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