Using the Zebrafish Lateral Line to Screen for Ototoxicity

Department of Otolaryngology-Head and Neck Surgery, University of Washington, Box 356515, Seattle, WA 98195, USA.
Journal of the Association for Research in Otolaryngology (Impact Factor: 2.6). 07/2008; 9(2):178-90. DOI: 10.1007/s10162-008-0118-y
Source: PubMed


The zebrafish is a valuable model for studying hair cell development, structure, genetics, and behavior. Zebrafish and other aquatic vertebrates have hair cells on their body surface organized into a sensory system called the lateral line. These hair cells are highly accessible and easily visualized using fluorescent dyes. Morphological and functional similarities to mammalian hair cells of the inner ear make the zebrafish a powerful preparation for studying hair cell toxicity. The ototoxic potential of drugs has historically been uncovered by anecdotal reports that have led to more formal investigation. Currently, no standard screen for ototoxicity exists in drug development. Thus, for the vast majority of Food and Drug Association (FDA)-approved drugs, the ototoxic potential remains unknown. In this study, we used 5-day-old zebrafish larvae to screen a library of 1,040 FDA-approved drugs and bioactives (NINDS Custom Collection II) for ototoxic effects in hair cells of the lateral line. Hair cell nuclei were selectively labeled using a fluorescent vital dye. For the initial screen, fish were exposed to drugs from the library at a 100-muM concentration for 1 h in 96-well tissue culture plates. Hair cell viability was assessed in vivo using fluorescence microscopy. One thousand forty drugs were rapidly screened for ototoxic effects. Seven known ototoxic drugs included in the library, including neomycin and cisplatin, were positively identified using these methods, as proof of concept. Fourteen compounds without previously known ototoxicity were discovered to be selectively toxic to hair cells. Dose-response curves for all 21 ototoxic compounds were determined by quantifying hair cell survival as a function of drug concentration. Dose-response relationships in the mammalian inner ear for two of the compounds without known ototoxicity, pentamidine isethionate and propantheline bromide, were then examined using in vitro preparations of the adult mouse utricle. Significant dose-dependent hair cell loss in the mouse utricle was demonstrated for both compounds. This study represents an important step in validating the use of the zebrafish lateral line as a screening tool for the identification of potentially ototoxic drugs.

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Available from: David W Raible, Jan 20, 2014
    • "Since genetic manipulation may be performed in zebrafish, the biological targets and modes of action of various compounds might be determined. Further, zebrafish have already been used as an established model organism in numerous studies that assess toxicity endpoints of compounds or their mechanisms of action (Berghmans et al. 2007; Tran et al. 2007; Chiu et al. 2008; Richards et al. 2008; Winter et al. 2008; Weber et al. 2015). Thus, the present study aimed to investigate the developmental toxicity, apoptotic induction, and mechanism of toxicity of the aqueous extract of M. pachycarpa (AEMP) using zebrafish as model organism. "

    Toxicological and Environmental Chemistry 09/2015; DOI:10.1080/02772248.2015.1093750 · 0.83 Impact Factor
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    • "As far as we know, these results are reported for the first time in zebrafish. Significant dose-dependent hair cell loss in the mouse utricle was demonstrated for both neomycin and gentamicin and this represents an important step in validating the use of the zebrafish lateral line as a screening tool for the identification of potentially ototoxic drugs (Chiu et al., 2008), and supports the use of the zebrafish as a pre-clinical indicator of drug-induced histological and functional ototoxicity (Buck et al., 2012). This study was aimed at providing an experimental model of ototoxicity using the hair cells of the lateral line system as a model, "
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    ABSTRACT: The hair cells of the lateral line system of fishes are morphologically and physiologically similar to the hair cells of the mammalian inner ear, also sharing its molecular characteristics. For this reason, it has been used as a powerful animal model to analyze in vivo ototoxicity. In this work, we examined the dose-dependent effects of two potent ototoxic aminoglycosides, neomycin and gentamicin, on the hair cells of two selected neuromasts (L1 and T1, the first of the trunk and the terminal located in the fin, respectively) of the lateral line in the ET4 transgenic zebrafish line. The hair cells of this strain selectively and constitutively display fluorescence. The fish were treated for 24 h at different doses (1, 2.5, 5, 10 and 100 μM levels) of both aminoglycosides. Immediately after treatment the morphology and the number of cells in L1 and T were analyzed under a fluorescence microscope. The results show that neomycin and gentamicin have different effects on the hair cell death at the same concentration, showing also different toxicity in L1 and T1 neuromasts. The toxicity observed in the hair cells of T1 neuromast was less than in L1 especially for the gentamicin treatment. These results demonstrate different sensitivity of hair cells of the lateral line to ototoxic drugs according to topographical localization and suggest the in vivo assay of the L1 neuromast of zebrafish larva and low doses of neomycin as an ideal model to study ototoxicity induced by aminoglycosides.
    Annals of anatomy = Anatomischer Anzeiger: official organ of the Anatomische Gesellschaft 07/2014; 196(4). DOI:10.1016/j.aanat.2014.01.005 · 1.48 Impact Factor
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    • "Detailed description of the utility of zebrafish as a drug discovery tool is provided elsewhere (Rubinstein, 2006; McGrath and Li, 2008; Sipes et al., 2011; Sukardi et al., 2011). Although it has been shown that zebrafish toxicological assays can attain a good level of predictivity, false-negatives and false-positives have been found to compromise the sensitivity and specificity of the assays used (Milan et al., 2003; Chiu et al., 2008; Mittelstadt et al., 2008; Redfern et al., 2008; Kokel et al., 2010). These studies, while sporadic in nature, underscored a neglected understanding of the ADME profile of drugs between zebrafish and human or other mammalian models which is affected by factors such as the route of administration and physiology of the fish. "
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    ABSTRACT: Early assessment of the toxicity potential of new molecules in pharmaceutical industry is a multi-dimensional task involving predictive systems and screening approaches to aid in the optimization of lead compounds prior to their entry into development phase. Due to the high attrition rate in the pharma industry in last few years, it has become imperative for the nonclinical toxicologist to focus on novel approaches which could be helpful for early screening of drug candidates. The need is that the toxicologists should change their classical approach to a more investigative approach. This review discusses the developments that allow toxicologists to anticipate safety problems and plan ways to address them earlier than ever before. This includes progress in the field of in vitro models, surrogate models, molecular toxicology, 'omics' technologies, translational safety biomarkers, stem-cell based assays and preclinical imaging. The traditional boundaries between teams focusing on efficacy/ safety and preclinical/ clinical aspects in the pharma industry are disappearing, and translational research-centric organizations with a focused vision of bringing drugs forward safely and rapidly are emerging. Today's toxicologist should collaborate with medicinal chemists, pharmacologists, and clinicians and these value-adding contributions will change traditional toxicologists from side-effect identifiers to drug development enablers. Copyright © 2013 John Wiley & Sons, Ltd.
    Journal of Applied Toxicology 06/2014; 34(6):576-94. DOI:10.1002/jat.2935 · 2.98 Impact Factor
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