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Ford LC, Lin HC, Zhou YH, Wright FA, Gombar VK, Sedykh A, Shah RR, Chiu WA, Rusyn I. Characterizing PFAS hazards and risks: a human population-based in vitro cardiotoxicity assessment strategy. Hum Genomics 2024; 18:92. [PMID: 39218963 PMCID: PMC11368000 DOI: 10.1186/s40246-024-00665-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2024] [Accepted: 08/20/2024] [Indexed: 09/04/2024] Open
Abstract
Per- and poly-fluoroalkyl substances (PFAS) are emerging contaminants of concern because of their wide use, persistence, and potential to be hazardous to both humans and the environment. Several PFAS have been designated as substances of concern; however, most PFAS in commerce lack toxicology and exposure data to evaluate their potential hazards and risks. Cardiotoxicity has been identified as a likely human health concern, and cell-based assays are the most sensible approach for screening and prioritization of PFAS. Human-induced pluripotent stem cell (iPSC)-derived cardiomyocytes are a widely used method to test for cardiotoxicity, and recent studies showed that many PFAS affect these cells. Because iPSC-derived cardiomyocytes are available from different donors, they also can be used to quantify human variability in responses to PFAS. The primary objective of this study was to characterize potential human cardiotoxic hazard, risk, and inter-individual variability in responses to PFAS. A total of 56 PFAS from different subclasses were tested in concentration-response using human iPSC-derived cardiomyocytes from 16 donors without known heart disease. Kinetic calcium flux and high-content imaging were used to evaluate biologically-relevant phenotypes such as beat frequency, repolarization, and cytotoxicity. Of the tested PFAS, 46 showed concentration-response effects in at least one phenotype and donor; however, a wide range of sensitivities were observed across donors. Inter-individual variability in the effects could be quantified for 19 PFAS, and risk characterization could be performed for 20 PFAS based on available exposure information. For most tested PFAS, toxicodynamic variability was within a factor of 10 and the margins of exposure were above 100. This study identified PFAS that may pose cardiotoxicity risk and have high inter-individual variability. It also demonstrated the feasibility of using a population-based human in vitro method to quantify population variability and identify cardiotoxicity risks of emerging contaminants.
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Affiliation(s)
- Lucie C Ford
- Department of Veterinary Physiology and Pharmacology, TAMU 4466, Texas A&M University, College Station, TX, 77843-4466, USA
| | - Hsing-Chieh Lin
- Department of Veterinary Physiology and Pharmacology, TAMU 4466, Texas A&M University, College Station, TX, 77843-4466, USA
| | - Yi-Hui Zhou
- Department of Biological Sciences and Statistics, North Carolina State University, Raleigh, NC, 27695, USA
- Bioinformatics Research Center, North Carolina State University, Raleigh, NC, 27695, USA
| | - Fred A Wright
- Department of Biological Sciences and Statistics, North Carolina State University, Raleigh, NC, 27695, USA
- Bioinformatics Research Center, North Carolina State University, Raleigh, NC, 27695, USA
| | | | | | | | - Weihsueh A Chiu
- Department of Veterinary Physiology and Pharmacology, TAMU 4466, Texas A&M University, College Station, TX, 77843-4466, USA
| | - Ivan Rusyn
- Department of Veterinary Physiology and Pharmacology, TAMU 4466, Texas A&M University, College Station, TX, 77843-4466, USA.
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2
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Tsai HHD, Ford LC, Burnett SD, Dickey AN, Wright FA, Chiu WA, Rusyn I. Informing Hazard Identification and Risk Characterization of Environmental Chemicals by Combining Transcriptomic and Functional Data from Human-Induced Pluripotent Stem-Cell-Derived Cardiomyocytes. Chem Res Toxicol 2024; 37:1428-1444. [PMID: 39046974 DOI: 10.1021/acs.chemrestox.4c00193] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/27/2024]
Abstract
Environmental chemicals may contribute to the global burden of cardiovascular disease, but experimental data are lacking to determine which substances pose the greatest risk. Human-induced pluripotent stem cell (iPSC)-derived cardiomyocytes are a high-throughput cardiotoxicity model that is widely used to test drugs and chemicals; however, most studies focus on exploring electro-physiological readouts. Gene expression data may provide additional molecular insights to be used for both mechanistic interpretation and dose-response analyses. Therefore, we hypothesized that both transcriptomic and functional data in human iPSC-derived cardiomyocytes may be used as a comprehensive screening tool to identify potential cardiotoxicity hazards and risks of the chemicals. To test this hypothesis, we performed concentration-response analysis of 464 chemicals from 12 classes, including both pharmaceuticals and nonpharmaceutical substances. Functional effects (beat frequency, QT prolongation, and asystole), cytotoxicity, and whole transcriptome response were evaluated. Points of departure were derived from phenotypic and transcriptomic data, and risk characterization was performed. Overall, 244 (53%) substances were active in at least one phenotype; as expected, pharmaceuticals with known cardiac liabilities were the most active. Positive chronotropy was the functional phenotype activated by the largest number of tested chemicals. No chemical class was particularly prone to pose a potential hazard to cardiomyocytes; a varying proportion (10-44%) of substances in each class had effects on cardiomyocytes. Transcriptomic data showed that 69 (15%) substances elicited significant gene expression changes; most perturbed pathways were highly relevant to known key characteristics of human cardiotoxicants. The bioactivity-to-exposure ratios showed that phenotypic- and transcriptomic-based POD led to similar results for risk characterization. Overall, our findings demonstrate how the integrative use of in vitro transcriptomic and phenotypic data from iPSC-derived cardiomyocytes not only offers a complementary approach for hazard and risk prioritization, but also enables mechanistic interpretation of the in vitro test results to increase confidence in decision-making.
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Affiliation(s)
- Han-Hsuan D Tsai
- Interdisciplinary Faculty of Toxicology, Texas A&M University, College Station, Texas 77843, United States
- Department of Veterinary Physiology and Pharmacology, Texas A&M University, College Station, Texas 77843, United States
| | - Lucie C Ford
- Interdisciplinary Faculty of Toxicology, Texas A&M University, College Station, Texas 77843, United States
- Department of Veterinary Physiology and Pharmacology, Texas A&M University, College Station, Texas 77843, United States
| | - Sarah D Burnett
- Interdisciplinary Faculty of Toxicology, Texas A&M University, College Station, Texas 77843, United States
- Department of Veterinary Physiology and Pharmacology, Texas A&M University, College Station, Texas 77843, United States
| | - Allison N Dickey
- Bioinformatics Research Center, North Carolina State University, Raleigh, North Carolina 27603, United States
| | - Fred A Wright
- Interdisciplinary Faculty of Toxicology, Texas A&M University, College Station, Texas 77843, United States
- Bioinformatics Research Center, North Carolina State University, Raleigh, North Carolina 27603, United States
- Department of Statistics and Bioinformatics Research Center, North Carolina State University, Raleigh, North Carolina 27603, United States
| | - Weihsueh A Chiu
- Interdisciplinary Faculty of Toxicology, Texas A&M University, College Station, Texas 77843, United States
- Department of Veterinary Physiology and Pharmacology, Texas A&M University, College Station, Texas 77843, United States
| | - Ivan Rusyn
- Interdisciplinary Faculty of Toxicology, Texas A&M University, College Station, Texas 77843, United States
- Department of Veterinary Physiology and Pharmacology, Texas A&M University, College Station, Texas 77843, United States
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3
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Pang L, Cai C, Aggarwal P, Wang D, Vijay V, Bagam P, Blamer J, Matter A, Turner A, Ren L, Papineau K, Srinivasasainagendra V, Tiwari HK, Yang X, Schnackenberg L, Mattes W, Broeckel U. Predicting oncology drug-induced cardiotoxicity with donor-specific iPSC-CMs-a proof-of-concept study with doxorubicin. Toxicol Sci 2024; 200:79-94. [PMID: 38547396 PMCID: PMC11199917 DOI: 10.1093/toxsci/kfae041] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/27/2024] Open
Abstract
Many oncology drugs have been found to induce cardiotoxicity in a subset of patients, which significantly limits their clinical use and impedes the benefit of lifesaving anticancer treatments. Human induced pluripotent stem cell-derived cardiomyocytes (iPSC-CMs) carry donor-specific genetic information and have been proposed for exploring the interindividual difference in oncology drug-induced cardiotoxicity. Herein, we evaluated the inter- and intraindividual variability of iPSC-CM-related assays and presented a proof of concept to prospectively predict doxorubicin (DOX)-induced cardiotoxicity (DIC) using donor-specific iPSC-CMs. Our findings demonstrated that donor-specific iPSC-CMs exhibited greater line-to-line variability than the intraindividual variability in impedance cytotoxicity and transcriptome assays. The variable and dose-dependent cytotoxic responses of iPSC-CMs resembled those observed in clinical practice and largely replicated the reported mechanisms. By categorizing iPSC-CMs into resistant and sensitive cell lines based on their time- and concentration-related phenotypic responses to DOX, we found that the sensitivity of donor-specific iPSC-CMs to DOX may predict in vivo DIC risk. Furthermore, we identified a differentially expressed gene, DND microRNA-mediated repression inhibitor 1 (DND1), between the DOX-resistant and DOX-sensitive iPSC-CMs. Our results support the utilization of donor-specific iPSC-CMs in assessing interindividual differences in DIC. Further studies will encompass a large panel of donor-specific iPSC-CMs to identify potential novel molecular and genetic biomarkers for predicting DOX and other oncology drug-induced cardiotoxicity.
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Affiliation(s)
- Li Pang
- Division of Systems Biology, National Center for Toxicological Research, U.S. Food and Drug Administration, Jefferson, Arkansas 72079, USA
| | - Chengzhong Cai
- Division of Systems Biology, National Center for Toxicological Research, U.S. Food and Drug Administration, Jefferson, Arkansas 72079, USA
| | - Praful Aggarwal
- Department of Pediatrics, Section of Genomic Pediatrics, Medical College of Wisconsin, Milwaukee, Wisconsin 53226, USA
| | - Dong Wang
- Division of Bioinformatics and Biostatistics, National Center for Toxicological Research, U.S. Food and Drug Administration, Jefferson, Arkansas 72079, USA
| | - Vikrant Vijay
- Division of Systems Biology, National Center for Toxicological Research, U.S. Food and Drug Administration, Jefferson, Arkansas 72079, USA
| | - Prathyusha Bagam
- Division of Systems Biology, National Center for Toxicological Research, U.S. Food and Drug Administration, Jefferson, Arkansas 72079, USA
| | - Jacob Blamer
- Department of Pediatrics, Section of Genomic Pediatrics, Medical College of Wisconsin, Milwaukee, Wisconsin 53226, USA
| | - Andrea Matter
- Department of Pediatrics, Section of Genomic Pediatrics, Medical College of Wisconsin, Milwaukee, Wisconsin 53226, USA
| | - Amy Turner
- Department of Pediatrics, Section of Genomic Pediatrics, Medical College of Wisconsin, Milwaukee, Wisconsin 53226, USA
| | - Lijun Ren
- Division of Systems Biology, National Center for Toxicological Research, U.S. Food and Drug Administration, Jefferson, Arkansas 72079, USA
| | - Katy Papineau
- Division of Systems Biology, National Center for Toxicological Research, U.S. Food and Drug Administration, Jefferson, Arkansas 72079, USA
| | - Vinodh Srinivasasainagendra
- Department of Biostatistics, School of Public Health, University of Alabama at Birmingham, Birmingham, Alabama 35294, USA
| | - Hemant K Tiwari
- Department of Biostatistics, School of Public Health, University of Alabama at Birmingham, Birmingham, Alabama 35294, USA
| | - Xi Yang
- Division of Pharmacology & Toxicology, Office of Cardiology, Hematology, Endocrinology, & Nephrology, Office of New Drug, Center for Drug Evaluation and Research, U.S. Food and Drug Administration, Silver Spring, Maryland 20903, USA
| | - Laura Schnackenberg
- Division of Systems Biology, National Center for Toxicological Research, U.S. Food and Drug Administration, Jefferson, Arkansas 72079, USA
| | - William Mattes
- Division of Systems Biology, National Center for Toxicological Research, U.S. Food and Drug Administration, Jefferson, Arkansas 72079, USA
| | - Ulrich Broeckel
- Department of Pediatrics, Section of Genomic Pediatrics, Medical College of Wisconsin, Milwaukee, Wisconsin 53226, USA
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Lu EH, Ford LC, Chen Z, Burnett SD, Rusyn I, Chiu WA. Evaluating scientific confidence in the concordance of in vitro and in vivo protective points of departure. Regul Toxicol Pharmacol 2024; 148:105596. [PMID: 38447894 PMCID: PMC11193089 DOI: 10.1016/j.yrtph.2024.105596] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2023] [Revised: 02/21/2024] [Accepted: 02/26/2024] [Indexed: 03/08/2024]
Abstract
To fulfil the promise of reducing reliance on mammalian in vivo laboratory animal studies, new approach methods (NAMs) need to provide a confident basis for regulatory decision-making. However, previous attempts to develop in vitro NAMs-based points of departure (PODs) have yielded mixed results, with PODs from U.S. EPA's ToxCast, for instance, appearing more conservative (protective) but poorly correlated with traditional in vivo studies. Here, we aimed to address this discordance by reducing the heterogeneity of in vivo PODs, accounting for species differences, and enhancing the biological relevance of in vitro PODs. However, we only found improved in vitro-to-in vivo concordance when combining the use of Bayesian model averaging-based benchmark dose modeling for in vivo PODs, allometric scaling for interspecies adjustments, and human-relevant in vitro assays with multiple induced pluripotent stem cell-derived models. Moreover, the available sample size was only 15 chemicals, and the resulting level of concordance was only fair, with correlation coefficients <0.5 and prediction intervals spanning several orders of magnitude. Overall, while this study suggests several ways to enhance concordance and thereby increase scientific confidence in vitro NAMs-based PODs, it also highlights challenges in their predictive accuracy and precision for use in regulatory decision making.
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Affiliation(s)
- En-Hsuan Lu
- Interdisciplinary Faculty of Toxicology and Department of Veterinary Physiology and Pharmacology, Texas A&M University, College Station, TX, 77843, USA
| | - Lucie C Ford
- Interdisciplinary Faculty of Toxicology and Department of Veterinary Physiology and Pharmacology, Texas A&M University, College Station, TX, 77843, USA
| | - Zunwei Chen
- Interdisciplinary Faculty of Toxicology and Department of Veterinary Physiology and Pharmacology, Texas A&M University, College Station, TX, 77843, USA
| | - Sarah D Burnett
- Interdisciplinary Faculty of Toxicology and Department of Veterinary Physiology and Pharmacology, Texas A&M University, College Station, TX, 77843, USA
| | - Ivan Rusyn
- Interdisciplinary Faculty of Toxicology and Department of Veterinary Physiology and Pharmacology, Texas A&M University, College Station, TX, 77843, USA
| | - Weihsueh A Chiu
- Interdisciplinary Faculty of Toxicology and Department of Veterinary Physiology and Pharmacology, Texas A&M University, College Station, TX, 77843, USA.
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Lin HC, Rusyn I, Chiu WA. Assessing proarrhythmic potential of environmental chemicals using a high throughput in vitro-in silico model with human induced pluripotent stem cell-derived cardiomyocytes. ALTEX 2024; 41:37-49. [PMID: 37921411 PMCID: PMC10898275 DOI: 10.14573/altex.2306231] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/23/2023] [Accepted: 10/19/2023] [Indexed: 11/04/2023]
Abstract
QT prolongation and the potentially fatal arrhythmia Torsades de Pointes are common causes for withdrawing or restricting drugs; however, little is known about similar liabilities of environmental chemicals. Current in vitro-in silico models for testing proarrhythmic liabilities, using human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CM), provide an opportunity to address this data gap. These methods are still low- to medium-throughput and not suitable for testing the tens of thousands of chemicals in commerce. We hypothesized that combining high-throughput population- based in vitro testing in hiPSC-CMs with a fully in silico data analysis workflow can offer sensitive and specific predictions of proarrhythmic potential. We calibrated the model with a published hiPSC-CM dataset of drugs known to be positive or negative for proarrhythmia and tested its performance using internal cross-validation and external validation. Additionally, we used computational down-sampling to examine three study designs for hiPSC-CM data: one replicate of one donor, five replicates of one donor, and one replicate of a population of five donors. We found that the population of five donors had the best performance for predicting proarrhythmic potential. The resulting model was then applied to predict the proarrhythmic potential of environmental chemicals, additionally characterizing risk through margin of exposure (MOE) calculations. Out of over 900 environmental chemicals tested, over 150 were predicted to have proarrhythmic potential, but only seven chemicals had a MOE < 1. We conclude that a high-throughput in vitro-in silico approach using population-based hiPSC-CM testing provides a reasonable strategy to screen environmental chemicals for proarrhythmic potential.
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Affiliation(s)
- Hsing-Chieh Lin
- Department of Veterinary Physiology and Pharmacology, College of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, TX, USA
| | - Ivan Rusyn
- Department of Veterinary Physiology and Pharmacology, College of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, TX, USA
| | - Weihsueh A. Chiu
- Department of Veterinary Physiology and Pharmacology, College of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, TX, USA
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6
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Kowalczewski A, Sakolish C, Hoang P, Liu X, Jacquir S, Rusyn I, Ma Z. Integrating nonlinear analysis and machine learning for human induced pluripotent stem cell-based drug cardiotoxicity testing. J Tissue Eng Regen Med 2022; 16:732-743. [PMID: 35621199 PMCID: PMC9719611 DOI: 10.1002/term.3325] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2021] [Revised: 05/13/2022] [Accepted: 05/17/2022] [Indexed: 01/16/2023]
Abstract
Utilizing recent advances in human induced pluripotent stem cell (hiPSC) technology, nonlinear analysis and machine learning we can create novel tools to evaluate drug-induced cardiotoxicity on human cardiomyocytes. With cardiovascular disease remaining the leading cause of death globally it has become imperative to create effective and modern tools to test the efficacy and toxicity of drugs to combat heart disease. The calcium transient signals recorded from hiPSC-derived cardiomyocytes (hiPSC-CMs) are highly complex and dynamic with great degrees of response characteristics to various drug treatments. However, traditional linear methods often fail to capture the subtle variation in these signals generated by hiPSC-CMs. In this work, we integrated nonlinear analysis, dimensionality reduction techniques and machine learning algorithms for better classifying the contractile signals from hiPSC-CMs in response to different drug exposure. By utilizing extracted parameters from a commercially available high-throughput testing platform, we were able to distinguish the groups with drug treatment from baseline controls, determine the drug exposure relative to IC50 values, and classify the drugs by its unique cardiac responses. By incorporating nonlinear parameters computed by phase space reconstruction, we were able to improve our machine learning algorithm's ability to predict cardiotoxic levels and drug classifications. We also visualized the effects of drug treatment and dosages with dimensionality reduction techniques, t-distributed stochastic neighbor embedding (t-SNE). We have shown that integration of nonlinear analysis and artificial intelligence has proven to be a powerful tool for analyzing cardiotoxicity and classifying toxic compounds through their mechanistic action.
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Affiliation(s)
- Andrew Kowalczewski
- Department of Biomedical & Chemical Engineering, Syracuse University, Syracuse NY, USA,BioInspired Syracuse Institute for Materials and Living Systems, Syracuse University, Syracuse NY, USA
| | - Courtney Sakolish
- Department of Veterinary Integrative Biosciences, Texas A&M University, College Station, TX, USA
| | - Plansky Hoang
- Department of Biomedical & Chemical Engineering, Syracuse University, Syracuse NY, USA,BioInspired Syracuse Institute for Materials and Living Systems, Syracuse University, Syracuse NY, USA
| | - Xiyuan Liu
- Department of Mechanical & Aerospace Engineering, Syracuse University, Syracuse NY, USA
| | - Sabir Jacquir
- Université Paris-Saclay, CNRS, Institut des Neurosciences Paris Saclay, Gif-sur-Yvette, France
| | - Ivan Rusyn
- Department of Veterinary Integrative Biosciences, Texas A&M University, College Station, TX, USA
| | - Zhen Ma
- Department of Biomedical & Chemical Engineering, Syracuse University, Syracuse NY, USA,BioInspired Syracuse Institute for Materials and Living Systems, Syracuse University, Syracuse NY, USA,Corresponding author Zhen Ma, PhD. Syracuse University ()
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7
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Model systems and organisms for addressing inter- and intra-species variability in risk assessment. Regul Toxicol Pharmacol 2022; 132:105197. [DOI: 10.1016/j.yrtph.2022.105197] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2022] [Revised: 05/20/2022] [Accepted: 05/25/2022] [Indexed: 12/12/2022]
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Daley MC, Mende U, Choi BR, McMullen PD, Coulombe KLK. Beyond pharmaceuticals: Fit-for-purpose new approach methodologies for environmental cardiotoxicity testing. ALTEX 2022; 40:103-116. [PMID: 35648122 PMCID: PMC10502740 DOI: 10.14573/altex.2109131] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/13/2021] [Accepted: 05/16/2022] [Indexed: 11/23/2022]
Abstract
Environmental factors play a substantial role in determining cardiovascular health, but data informing the risks presented by environmental toxicants is insufficient. In vitro new approach methodologies (NAMs) offer a promising approach with which to address the limitations of traditional in vivo and in vitro assays for assessing cardiotoxicity. Driven largely by the needs of pharmaceutical toxicity testing, considerable progress in developing NAMs for cardiotoxicity analysis has already been made. As the scientific and regulatory interest in NAMs for environmental chemicals continues to grow, a thorough understanding of the unique features of environmental cardiotoxicants and their associated cardiotoxicities is needed. Here, we review the key characteristics of as well as important regulatory and biological considerations for fit-for-purpose NAMs for environmental cardiotoxicity. By emphasizing the challenges and opportunities presented by NAMs for environmental cardiotoxicity we hope to accelerate their development, acceptance, and application.
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Affiliation(s)
- Mark C Daley
- Center for Biomedical Engineering, School of Engineering and Division of Biology and Medicine, Brown University, Providence, RI, USA
| | - Ulrike Mende
- Cardiovascular Research Center, Cardiovascular Institute, Rhode Island Hospital and Warren Alpert Medical School of Brown University, Providence, RI, USA
| | - Bum-Rak Choi
- Cardiovascular Research Center, Cardiovascular Institute, Rhode Island Hospital and Warren Alpert Medical School of Brown University, Providence, RI, USA
| | | | - Kareen L K Coulombe
- Center for Biomedical Engineering, School of Engineering and Division of Biology and Medicine, Brown University, Providence, RI, USA
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Rusyn I, Chiu WA. Decision-Making with New Approach Methodologies: Time to Replace Default Uncertainty Factors with Data. Toxicol Sci 2022; 189:148-149. [PMID: 35404442 PMCID: PMC9801706 DOI: 10.1093/toxsci/kfac033] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Affiliation(s)
- Ivan Rusyn
- To whom correspondence should be addressed.Fax: 979-847-8981. E-mail:
| | - Weihsueh A Chiu
- Department of Veterinary Physiology and Pharmacology, College of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, Texas 77843, USA
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11
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A tiered approach to population-based in vitro testing for cardiotoxicity: Balancing estimates of potency and variability. J Pharmacol Toxicol Methods 2022; 114:107154. [PMID: 34999233 PMCID: PMC8930538 DOI: 10.1016/j.vascn.2022.107154] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2021] [Revised: 11/11/2021] [Accepted: 01/01/2022] [Indexed: 12/11/2022]
Abstract
Population-wide in vitro studies for characterization of cardiotoxicity hazard, risk, and population variability show that human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CM) are a powerful and high-throughput testing platform for drugs and environmental chemicals alike. However, studies in multiple donor-derived hiPSC-CMs, across large libraries of chemicals tested in concentration-response are technically complex, and study design optimization is needed to determine sufficient and fit-for-purpose population size considerations. Therefore, we tested a hypothesis that a computational down-sampling analysis based on the data from hiPSC-CM screening of 136 diverse compounds in a population of 43 non-diseased donors, including multiple replicates of the "standard" donor hiPSC-CMs, will inform optimal study designs depending on the decision context (hazard, risk and/or inter-individual variability in cardiotoxicity). Through 50 independent random subsamples of 5, 10, or 20 donors, we estimated accuracy and precision for quantifying potency, inter-individual variability, and QT prolongation risk; the results were compared to the full 43-donor cohort. We found that for potency and clinical risk of QT prolongation, a cohort of 5 randomly-selected unique donors provides accurate and precise estimates. Larger cohort sizes afforded marginal improvements, and 5 replicates of a single donor performed worse. For estimating inter-individual variability, cohorts of at least 20 donors are needed, with smaller populations on average showing bias towards underestimation in population variance. Collectively, this study shows that a variable-size hiPSC-CM-based population-wide in vitro model can be used in a number of decision scenarios for identifying cardiotoxic hazards of drugs and environmental chemicals in the population context.
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12
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Chen Z, Jang S, Kaihatu JM, Zhou YH, Wright FA, Chiu WA, Rusyn I. Potential Human Health Hazard of Post-Hurricane Harvey Sediments in Galveston Bay and Houston Ship Channel: A Case Study of Using In Vitro Bioactivity Data to Inform Risk Management Decisions. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2021; 18:13378. [PMID: 34948986 PMCID: PMC8702027 DOI: 10.3390/ijerph182413378] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/20/2021] [Revised: 12/08/2021] [Accepted: 12/16/2021] [Indexed: 01/14/2023]
Abstract
Natural and anthropogenic disasters may be associated with redistribution of chemical contaminants in the environment; however, current methods for assessing hazards and risks of complex mixtures are not suitable for disaster response. This study investigated the suitability of in vitro toxicity testing methods as a rapid means of identifying areas of potential human health concern. We used sediment samples (n = 46) from Galveston Bay and the Houston Ship Channel (GB/HSC) areas after hurricane Harvey, a disaster event that led to broad redistribution of chemically-contaminated sediments, including deposition of the sediment on shore due to flooding. Samples were extracted with cyclohexane and dimethyl sulfoxide and screened in a compendium of human primary or induced pluripotent stem cell (iPSC)-derived cell lines from different tissues (hepatocytes, neuronal, cardiomyocytes, and endothelial) to test for concentration-dependent effects on various functional and cytotoxicity phenotypes (n = 34). Bioactivity data were used to map areas of potential concern and the results compared to the data on concentrations of polycyclic aromatic hydrocarbons (PAHs) in the same samples. We found that setting remediation goals based on reducing bioactivity is protective of both "known" risks associated with PAHs and "unknown" risks associated with bioactivity, but the converse was not true for remediation based on PAH risks alone. Overall, we found that in vitro bioactivity can be used as a comprehensive indicator of potential hazards and is an example of a new approach method (NAM) to inform risk management decisions on site cleanup.
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Affiliation(s)
- Zunwei Chen
- Interdisciplinary Faculty of Toxicology, Texas A&M University, College Station, TX 77843, USA; (Z.C.); (S.J.); (W.A.C.)
| | - Suji Jang
- Interdisciplinary Faculty of Toxicology, Texas A&M University, College Station, TX 77843, USA; (Z.C.); (S.J.); (W.A.C.)
| | - James M. Kaihatu
- Civil & Environmental Engineering and Ocean Engineering, Texas A&M University, College Station, TX 77843, USA;
| | - Yi-Hui Zhou
- Biological Sciences and Statistics, North Carolina State University, Raleigh, NC 27695, USA; (Y.-H.Z.); (F.A.W.)
| | - Fred A. Wright
- Biological Sciences and Statistics, North Carolina State University, Raleigh, NC 27695, USA; (Y.-H.Z.); (F.A.W.)
| | - Weihsueh A. Chiu
- Interdisciplinary Faculty of Toxicology, Texas A&M University, College Station, TX 77843, USA; (Z.C.); (S.J.); (W.A.C.)
| | - Ivan Rusyn
- Interdisciplinary Faculty of Toxicology, Texas A&M University, College Station, TX 77843, USA; (Z.C.); (S.J.); (W.A.C.)
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13
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Burnett SD, Blanchette AD, Chiu WA, Rusyn I. Cardiotoxicity Hazard and Risk Characterization of ToxCast Chemicals Using Human Induced Pluripotent Stem Cell-Derived Cardiomyocytes from Multiple Donors. Chem Res Toxicol 2021; 34:2110-2124. [PMID: 34448577 PMCID: PMC8762671 DOI: 10.1021/acs.chemrestox.1c00203] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Heart disease remains a significant human health burden worldwide with a significant fraction of morbidity attributable to environmental exposures. However, the extent to which the thousands of chemicals in commerce and the environment may contribute to heart disease morbidity is largely unknown, because in contrast to pharmaceuticals, environmental chemicals are seldom tested for potential cardiotoxicity. Human induced pluripotent stem cell (iPSC)-derived cardiomyocytes have become an informative in vitro model for cardiotoxicity testing of drugs with the availability of cells from multiple individuals allowing in vitro testing of population variability. In this study, we hypothesized that a panel of iPSC-derived cardiomyocytes from healthy human donors can be used to screen for the potential cardiotoxicity hazard and risk of environmental chemicals. We conducted concentration-response testing of 1029 chemicals (drugs, pesticides, flame retardants, polycyclic aromatic hydrocarbons (PAHs), plasticizers, industrial chemicals, food/flavor/fragrance agents, etc.) in iPSC-derived cardiomyocytes from 5 donors. We used kinetic calcium flux and high-content imaging to derive quantitative measures as inputs into Bayesian population concentration-response modeling of the effects of each chemical. We found that many environmental chemicals pose a hazard to human cardiomyocytes in vitro with more than half of all chemicals eliciting positive or negative chronotropic or arrhythmogenic effects. However, most of the tested environmental chemicals for which human exposure and high-throughput toxicokinetics data were available had wide margins of exposure and, thus, do not appear to pose a significant human health risk in a general population. Still, relatively narrow margins of exposure (<100) were estimated for some perfuoroalkyl substances and phthalates, raising concerns that cumulative exposures may pose a cardiotoxicity risk. Collectively, this study demonstrated the value of using a population-based human in vitro model for rapid, high-throughput hazard and risk characterization of chemicals for which little to no cardiotoxicity data are available from guideline studies in animals.
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Affiliation(s)
- Sarah D. Burnett
- Department of Veterinary Integrative Biosciences, Texas A&M University, College Station, TX 77843-4458, USA
| | - Alexander D. Blanchette
- Department of Veterinary Integrative Biosciences, Texas A&M University, College Station, TX 77843-4458, USA
| | - Weihsueh A. Chiu
- Department of Veterinary Integrative Biosciences, Texas A&M University, College Station, TX 77843-4458, USA
| | - Ivan Rusyn
- Department of Veterinary Integrative Biosciences, Texas A&M University, College Station, TX 77843-4458, USA
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Lind L, Araujo JA, Barchowsky A, Belcher S, Berridge BR, Chiamvimonvat N, Chiu WA, Cogliano VJ, Elmore S, Farraj AK, Gomes AV, McHale CM, Meyer-Tamaki KB, Posnack NG, Vargas HM, Yang X, Zeise L, Zhou C, Smith MT. Key Characteristics of Cardiovascular Toxicants. ENVIRONMENTAL HEALTH PERSPECTIVES 2021; 129:95001. [PMID: 34558968 PMCID: PMC8462506 DOI: 10.1289/ehp9321] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
BACKGROUND The concept of chemical agents having properties that confer potential hazard called key characteristics (KCs) was first developed to identify carcinogenic hazards. Identification of KCs of cardiovascular (CV) toxicants could facilitate the systematic assessment of CV hazards and understanding of assay and data gaps associated with current approaches. OBJECTIVES We sought to develop a consensus-based synthesis of scientific evidence on the KCs of chemical and nonchemical agents known to cause CV toxicity along with methods to measure them. METHODS An expert working group was convened to discuss mechanisms associated with CV toxicity. RESULTS The group identified 12 KCs of CV toxicants, defined as exogenous agents that adversely interfere with function of the CV system. The KCs were organized into those primarily affecting cardiac tissue (numbers 1-4 below), the vascular system (5-7), or both (8-12), as follows: 1) impairs regulation of cardiac excitability, 2) impairs cardiac contractility and relaxation, 3) induces cardiomyocyte injury and death, 4) induces proliferation of valve stroma, 5) impacts endothelial and vascular function, 6) alters hemostasis, 7) causes dyslipidemia, 8) impairs mitochondrial function, 9) modifies autonomic nervous system activity, 10) induces oxidative stress, 11) causes inflammation, and 12) alters hormone signaling. DISCUSSION These 12 KCs can be used to help identify pharmaceuticals and environmental pollutants as CV toxicants, as well as to better understand the mechanistic underpinnings of their toxicity. For example, evidence exists that fine particulate matter [PM ≤2.5μm in aerodynamic diameter (PM2.5)] air pollution, arsenic, anthracycline drugs, and other exogenous chemicals possess one or more of the described KCs. In conclusion, the KCs could be used to identify potential CV toxicants and to define a set of test methods to evaluate CV toxicity in a more comprehensive and standardized manner than current approaches. https://doi.org/10.1289/EHP9321.
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Affiliation(s)
- Lars Lind
- Department of Medical Sciences, Clinical Epidemiology, University of Uppsala, Sweden
| | - Jesus A. Araujo
- Division of Cardiology, David Geffen School of Medicine at University of California Los Angeles (UCLA), UCLA, Los Angeles, California, USA
- Department of Environmental Health Sciences, Fielding School of Public Health and Molecular Biology Institute, UCLA, Los Angeles, California, USA
| | - Aaron Barchowsky
- Department of Environmental and Occupational Health, Graduate School of Public Health, University of Pittsburgh, Pennsylvania, USA
| | - Scott Belcher
- Department of Biological Sciences, North Carolina State University, North Carolina, USA
| | - Brian R. Berridge
- Division of the National Toxicology Program, National Institute of Environmental Health Sciences, National Institutes of Health, Department of Health and Human Services, Research Triangle Park, North Carolina, USA
| | - Nipavan Chiamvimonvat
- Department of Internal Medicine, University of California, Davis, Davis, California, USA
| | - Weihsueh A. Chiu
- College of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, Texas, USA
| | - Vincent J. Cogliano
- Office of Environmental Health Hazard Assessment, California Environmental Protection Agency (EPA), Oakland, California, USA
| | - Sarah Elmore
- Office of Environmental Health Hazard Assessment, California Environmental Protection Agency (EPA), Oakland, California, USA
| | - Aimen K. Farraj
- Public Health and Integrated Toxicology Division, Center for Public Health and Environmental Assessment, U.S. EPA, Research Triangle Park, North Carolina, USA
| | - Aldrin V. Gomes
- Department of Neurobiology, Physiology and Behavior, College of Biological Sciences, University of California, Davis, Davis, California, USA
| | - Cliona M. McHale
- Division of Environmental Health Sciences, School of Public Health, University of California, Berkeley, Berkeley, California, USA
| | | | - Nikki Gillum Posnack
- Children’s National Heart Institute and the Sheikh Zayed Institute for Pediatric Surgical Innovation, Children’s National Hospital, Washington, DC, USA
| | - Hugo M. Vargas
- Translational Safety & Bioanalytical Sciences, Amgen, Inc., Thousand Oaks, California, USA
| | - Xi Yang
- Division of Pharmacology and Toxicology, Office of Cardiology, Hematology, Endocrinology, and Nephrology, Center for Drug Evaluation and Research, Food and Drug Administration, Silver Spring, Maryland, USA
| | - Lauren Zeise
- Office of Environmental Health Hazard Assessment, California Environmental Protection Agency (EPA), Oakland, California, USA
| | - Changcheng Zhou
- Division of Biomedical Sciences, School of Medicine, University of California, Riverside, Riverside, California, USA
| | - Martyn T. Smith
- Division of Environmental Health Sciences, School of Public Health, University of California, Berkeley, Berkeley, California, USA
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15
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Blanchette AD, Burnett SD, Grimm FA, Rusyn I, Chiu WA. A Bayesian Method for Population-wide Cardiotoxicity Hazard and Risk Characterization Using an In Vitro Human Model. Toxicol Sci 2021; 178:391-403. [PMID: 33078833 DOI: 10.1093/toxsci/kfaa151] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
Human induced pluripotent stem cell (iPSC)-derived cardiomyocytes are an established model for testing potential chemical hazards. Interindividual variability in toxicodynamic sensitivity has also been demonstrated in vitro; however, quantitative characterization of the population-wide variability has not been fully explored. We sought to develop a method to address this gap by combining a population-based iPSC-derived cardiomyocyte model with Bayesian concentration-response modeling. A total of 136 compounds, including 54 pharmaceuticals and 82 environmental chemicals, were tested in iPSC-derived cardiomyocytes from 43 nondiseased humans. Hierarchical Bayesian population concentration-response modeling was conducted for 5 phenotypes reflecting cardiomyocyte function or viability. Toxicodynamic variability was quantified through the derivation of chemical- and phenotype-specific variability factors. Toxicokinetic modeling was used for probabilistic in vitro-to-in vivo extrapolation to derive population-wide margins of safety for pharmaceuticals and margins of exposure for environmental chemicals. Pharmaceuticals were found to be active across all phenotypes. Over half of tested environmental chemicals showed activity in at least one phenotype, most commonly positive chronotropy. Toxicodynamic variability factor estimates for the functional phenotypes were greater than those for cell viability, usually exceeding the generally assumed default of approximately 3. Population variability-based margins of safety for pharmaceuticals were correctly predicted to be relatively narrow, including some below 10; however, margins of exposure for environmental chemicals, based on population exposure estimates, generally exceeded 1000, suggesting they pose little risk at current general population exposures even to sensitive subpopulations. Overall, this study demonstrates how a high-throughput, human population-based, in vitro-in silico model can be used to characterize toxicodynamic population variability in cardiotoxic risk.
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Affiliation(s)
- Alexander D Blanchette
- Department of Veterinary Integrative Biosciences, Texas A&M University, College Station, Texas 77843-4458
| | - Sarah D Burnett
- Department of Veterinary Integrative Biosciences, Texas A&M University, College Station, Texas 77843-4458
| | - Fabian A Grimm
- Department of Veterinary Integrative Biosciences, Texas A&M University, College Station, Texas 77843-4458
| | - Ivan Rusyn
- Department of Veterinary Integrative Biosciences, Texas A&M University, College Station, Texas 77843-4458
| | - Weihsueh A Chiu
- Department of Veterinary Integrative Biosciences, Texas A&M University, College Station, Texas 77843-4458
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16
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Burnett SD, Blanchette AD, Chiu WA, Rusyn I. Human induced pluripotent stem cell (iPSC)-derived cardiomyocytes as an in vitro model in toxicology: strengths and weaknesses for hazard identification and risk characterization. Expert Opin Drug Metab Toxicol 2021; 17:887-902. [PMID: 33612039 DOI: 10.1080/17425255.2021.1894122] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
INTRODUCTION Human induced pluripotent stem cell (iPSC)-derived cardiomyocytes is one of the most widely used cell-based models that resulted from the discovery of how non-embryonic stem cells can be differentiated into multiple cell types. In just one decade, iPSC-derived cardiomyocytes went from a research lab to widespread use in biomedical research and preclinical safety evaluation for drugs and other chemicals. AREAS COVERED This manuscript reviews data on toxicology applications of human iPSC-derived cardiomyocytes. We detail the outcome of a systematic literature search on their use (i) in hazard assessment for cardiotoxicity liabilities, (ii) for risk characterization, (iii) as models for population variability, and (iv) in studies of personalized medicine and disease. EXPERT OPINION iPSC-derived cardiomyocytes are useful to increase the accuracy, precision, and efficiency of cardiotoxicity hazard identification for both drugs and non-pharmaceuticals, with recent efforts beginning to demonstrate their utility for risk characterization. Notable limitations include the needs to improve the maturation of cells in culture, to better understand their potential use identifying structural cardiotoxicity, and for additional case studies involving population-wide and disease-specific risk characterization. Ultimately, the greatest future benefits are likely for non-pharmaceutical chemicals, filling a critical gap where no routine testing for cardiotoxicity is currently performed.
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Affiliation(s)
- Sarah D Burnett
- Department of Veterinary Integrative Biosciences, Texas A&M University, College Station, TX, USA
| | - Alexander D Blanchette
- Department of Veterinary Integrative Biosciences, Texas A&M University, College Station, TX, USA
| | - Weihsueh A Chiu
- Department of Veterinary Integrative Biosciences, Texas A&M University, College Station, TX, USA
| | - Ivan Rusyn
- Department of Veterinary Integrative Biosciences, Texas A&M University, College Station, TX, USA
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Luo YS, Chen Z, Blanchette AD, Zhou YH, Wright FA, Baker ES, Chiu WA, Rusyn I. Relationships between constituents of energy drinks and beating parameters in human induced pluripotent stem cell (iPSC)-Derived cardiomyocytes. Food Chem Toxicol 2021; 149:111979. [PMID: 33450301 DOI: 10.1016/j.fct.2021.111979] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2020] [Revised: 01/05/2021] [Accepted: 01/06/2021] [Indexed: 12/24/2022]
Abstract
Consumption of energy drinks has been associated with adverse cardiovascular effects; however, little is known about the ingredients that may contribute to these effects. We therefore characterized the chemical profiles and in vitro effects of energy drinks and their ingredients on human induced pluripotent stem cell (iPSC)-derived cardiomyocytes, and identified the putative active ingredients using a multivariate prediction model. Energy drinks from 17 widely-available over-the-counter brands were evaluated in this study. The concentrations of six common ingredients (caffeine, taurine, riboflavin, pantothenic acid, adenine, and L-methionine) were quantified by coupling liquid chromatography with a triple quadrupole mass spectrometer for the acquisition of LC-MS/MS spectra. In addition, untargeted analyses for each beverage were performed with a platform combining LC, ion mobility spectrometry and mass spectrometry (LC-IMS-MS) measurements. Approximately 300 features were observed across samples in the untargeted studies, and of these ~100 were identified. In vitro effects of energy drinks and some of their ingredients were then tested in iPSC-derived cardiomyocytes. Data on the beat rate (positive and negative chronotropy), ion channel function (QT prolongation), and cytotoxicity were collected in a dilution series. We found that some of the energy drinks elicited adverse effects on the cardiomyocytes with the most common being an increase in the beat rate, while QT prolongation was also observed at the lowest concentrations. Finally, concentration addition modeling using quantitative data from the 6 common ingredients and multivariate prediction modeling was used to determine potential ingredients responsible for the adverse effects on the cardiomyocytes. These analyses suggested theophylline, adenine, and azelate as possibly contributing to the in vitro effects of energy drinks on QT prolongation in cardiomyocytes.
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Affiliation(s)
- Yu-Syuan Luo
- Department of Veterinary Integrative Biosciences, Texas A&M University, College Station, TX, USA
| | - Zunwei Chen
- Department of Veterinary Integrative Biosciences, Texas A&M University, College Station, TX, USA
| | - Alexander D Blanchette
- Department of Veterinary Integrative Biosciences, Texas A&M University, College Station, TX, USA
| | - Yi-Hui Zhou
- Departments of Statistics and Biological Sciences, North Carolina State University, Raleigh, NC, USA
| | - Fred A Wright
- Departments of Statistics and Biological Sciences, North Carolina State University, Raleigh, NC, USA
| | - Erin S Baker
- Department of Chemistry, North Carolina State University, Raleigh, NC, USA
| | - Weihsueh A Chiu
- Department of Veterinary Integrative Biosciences, Texas A&M University, College Station, TX, USA
| | - Ivan Rusyn
- Department of Veterinary Integrative Biosciences, Texas A&M University, College Station, TX, USA.
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18
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Hsieh NH, Chen Z, Rusyn I, Chiu WA. Risk Characterization and Probabilistic Concentration-Response Modeling of Complex Environmental Mixtures Using New Approach Methodologies (NAMs) Data from Organotypic in Vitro Human Stem Cell Assays. ENVIRONMENTAL HEALTH PERSPECTIVES 2021; 129:17004. [PMID: 33395322 PMCID: PMC7781439 DOI: 10.1289/ehp7600] [Citation(s) in RCA: 28] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/03/2020] [Revised: 12/05/2020] [Accepted: 12/09/2020] [Indexed: 05/27/2023]
Abstract
BACKGROUND Risk assessment of chemical mixtures or complex substances remains a major methodological challenge due to lack of available hazard or exposure data. Therefore, risk assessors usually infer hazard or risk from data on the subset of constituents with available toxicity values. OBJECTIVES We evaluated the validity of the widely used traditional mixtures risk assessment paradigms, Independent Action (IA) and Concentration Addition (CA), with new approach methodologies (NAMs) data from human cell-based in vitro assays. METHODS A diverse set of 42 chemicals was tested both individually and as mixtures for functional and cytotoxic effects in vitro. A panel of induced pluripotent stem cell (iPSCs)-derived models (hepatocytes, cardiomyocytes, endothelial, and neurons) and one primary cell type (HUVEC) were used. Bayesian concentration-response modeling of individual chemicals or their mixtures was performed for a total of 47 phenotypes to derive point-of-departure (POD) values. Probabilistic IA or CA was conducted to estimate the mixture effects based on the bioactivity profiles from the individual chemicals and compared with mixture bioactivity. RESULTS All mixtures showed significant bioactivity, even though some were constructed using individual chemical concentrations considered "low" or "safe." Even though CA is much more accurate as a predictor of mixture effects in comparison with IA, with CA-based POD typically within an order of magnitude of the actual mixture, in some cases, the bioactivity of the mixtures appeared to be much greater than that of their components under either additivity assumption. DISCUSSION These results suggest that CA is a preferred first approximation for predicting mixture toxicity when data for all constituents are available. However, because the accuracy of additivity assumptions varies greatly across phenotypes, we posit that mixtures and complex substances need to be directly tested for their hazard potential. NAMs provide a practical solution that rapidly yields highly informative data for mixtures risk assessment. https://doi.org/10.1289/EHP7600.
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Affiliation(s)
- Nan-Hung Hsieh
- Interdisciplinary Faculty of Toxicology and Department of Veterinary Integrative Biosciences, College of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, Texas, USA
| | - Zunwei Chen
- Interdisciplinary Faculty of Toxicology and Department of Veterinary Integrative Biosciences, College of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, Texas, USA
| | - Ivan Rusyn
- Interdisciplinary Faculty of Toxicology and Department of Veterinary Integrative Biosciences, College of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, Texas, USA
| | - Weihsueh A. Chiu
- Interdisciplinary Faculty of Toxicology and Department of Veterinary Integrative Biosciences, College of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, Texas, USA
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19
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Pang L. Toxicity testing in the era of induced pluripotent stem cells: A perspective regarding the use of patient-specific induced pluripotent stem cell–derived cardiomyocytes for cardiac safety evaluation. CURRENT OPINION IN TOXICOLOGY 2020. [DOI: 10.1016/j.cotox.2020.04.001] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
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20
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Van Driest SL, van der Graaf PH. Induced Pluripotent Stem Cells: From the Bedside to the Bench, and Hopefully Back Again. Clin Pharmacol Ther 2020; 108:173-175. [PMID: 32663332 DOI: 10.1002/cpt.1924] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2020] [Accepted: 05/27/2020] [Indexed: 12/28/2022]
Affiliation(s)
- Sara L Van Driest
- Departments of Pediatrics and Medicine, Vanderbilt University Medical Center, Nashville, Tennessee, USA
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21
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Grimm FA, Klaren WD, Li X, Lehmler HJ, Karmakar M, Robertson LW, Chiu WA, Rusyn I. Cardiovascular Effects of Polychlorinated Biphenyls and Their Major Metabolites. ENVIRONMENTAL HEALTH PERSPECTIVES 2020; 128:77008. [PMID: 32701041 PMCID: PMC7377239 DOI: 10.1289/ehp7030] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
BACKGROUND Xenobiotic metabolism is complex, and accounting for bioactivation and detoxification processes of chemicals remains among the most challenging aspects for decision making with in vitro new approach methods data. OBJECTIVES Considering the physiological relevance of human organotypic culture models and their utility for high-throughput screening, we hypothesized that multidimensional chemical-biological profiling of chemicals and their major metabolites is a sensible alternative for the toxicological characterization of parent molecules vs. metabolites in vitro. METHODS In this study, we tested 25 polychlorinated biphenyls (PCBs) [PCB 3, 11, 52, 126, 136, and 153 and their relevant metabolites (hydroxylated, methoxylated, sulfated, and quinone)] in concentration-response (10 nM-100μM) for effects in human induced pluripotent stem cell (iPSC)-derived cardiomyocytes (CMs) and endothelial cells (ECs) (iPSC-derived and HUVECs). Functional phenotypic end points included effects on beating parameters and intracellular Ca2+ flux in CMs and inhibition of tubulogenesis in ECs. High-content imaging was used to evaluate cytotoxicity, mitochondrial integrity, and oxidative stress. RESULTS Data integration of a total of 19 physicochemical descriptors and 36 in vitro phenotypes revealed that chlorination status and metabolite class are strong predictors of the in vitro cardiovascular effects of PCBs. Oxidation of PCBs, especially to di-hydroxylated and quinone metabolites, was associated with the most pronounced effects, whereas sulfation and methoxylation of PCBs resulted in diminished bioactivity. DISCUSSION Risk characterization analysis showed that although in vitro derived effective concentrations exceeded the levels measured in the general population, risks cannot be ruled out due to the potential for population variability in susceptibility and the need to fill data gaps using read-across approaches. This study demonstrated a strategy for how in vitro data can be used to characterize human health risks from PCBs and their metabolites. https://doi.org/10.1289/EHP7030.
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Affiliation(s)
- Fabian A. Grimm
- Department of Veterinary Integrative Biosciences, College of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, Texas, USA
| | - William D. Klaren
- Department of Veterinary Integrative Biosciences, College of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, Texas, USA
| | - Xueshu Li
- Department of Occupational and Environmental Health, College of Public Health, The University of Iowa, Iowa City, Iowa, USA
| | - Hans-Joachim Lehmler
- Department of Occupational and Environmental Health, College of Public Health, The University of Iowa, Iowa City, Iowa, USA
| | - Moumita Karmakar
- Department of Statistics, College of Science, Texas A&M University, College Station, Texas, USA
| | - Larry W. Robertson
- Department of Occupational and Environmental Health, College of Public Health, The University of Iowa, Iowa City, Iowa, USA
| | - Weihsueh A. Chiu
- Department of Veterinary Integrative Biosciences, College of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, Texas, USA
| | - Ivan Rusyn
- Department of Veterinary Integrative Biosciences, College of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, Texas, USA
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Chen Z, Liu Y, Wright FA, Chiu WA, Rusyn I. Rapid hazard characterization of environmental chemicals using a compendium of human cell lines from different organs. ALTEX 2020; 37:623-638. [PMID: 32521033 PMCID: PMC7941183 DOI: 10.14573/altex.2002291] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/29/2020] [Accepted: 06/08/2020] [Indexed: 02/07/2023]
Abstract
The lack of adequate toxicity data for the vast majority of chemicals in the environment has spurred the development of new approach methodologies (NAMs). This study aimed to develop a practical high-throughput in vitro model for rapidly evaluating potential hazards of chemicals using a small number of human cells. Forty-two compounds were tested using human induced pluripotent stem cell (iPSC)-derived cells (hepatocytes, neurons, cardiomyocytes and endothelial cells), and a primary endothelial cell line. Both functional and cytotoxicity endpoints were evaluated using high-content imaging. Concentration-response was used to derive points-of-departure (POD). PODs were integrated with ToxPi and used as surrogate NAM-based PODs for risk characterization. We found chemical class-specific similarity among the chemicals tested; metal salts exhibited the highest overall bioactivity. We also observed cell type-specific patterns among classes of chemicals, indicating the ability of the proposed in vitro model to recognize effects on different cell types. Compared to available NAM datasets, such as ToxCast/Tox21 and chemical structure-based descriptors, we found that the data from the five-cell-type model was as good or even better in assigning compounds to chemical classes. Additionally, the PODs from this model performed well as a conservative surrogate for regulatory in vivo PODs and were less likely to underestimate in vivo potency and potential risk compared to other NAM-based PODs. In summary, we demonstrate the potential of this in vitro screening model to inform rapid risk-based decision-making through ranking, clustering, and assessment of both hazard and risks of diverse environmental chemicals.
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Affiliation(s)
- Zunwei Chen
- Interdisciplinary Faculty of Toxicology, College of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, TX, USA
- Department of Veterinary Integrative Biosciences, College of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, TX, USA
| | - Yizhong Liu
- Interdisciplinary Faculty of Toxicology, College of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, TX, USA
- Department of Veterinary Integrative Biosciences, College of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, TX, USA
| | - Fred A. Wright
- Bioinformatics Research Center, North Carolina State University, Raleigh, NC, USA
- Departments of Statistics and Biological Sciences, North Carolina State University, Raleigh, NC, USA
| | - Weihsueh A. Chiu
- Interdisciplinary Faculty of Toxicology, College of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, TX, USA
- Department of Veterinary Integrative Biosciences, College of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, TX, USA
| | - Ivan Rusyn
- Interdisciplinary Faculty of Toxicology, College of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, TX, USA
- Department of Veterinary Integrative Biosciences, College of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, TX, USA
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Wei F, Pourrier M, Strauss DG, Stockbridge N, Pang L. Effects of Electrical Stimulation on hiPSC-CM Responses to Classic Ion Channel Blockers. Toxicol Sci 2020; 174:254-265. [DOI: 10.1093/toxsci/kfaa010] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Abstract
Human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs) hold great potential for personalized cardiac safety prediction, particularly for that of drug-induced proarrhythmia. However, hiPSC-CMs fire spontaneously and the variable beat rates of cardiomyocytes can be a confounding factor that interferes with data interpretation. Controlling beat rates with pacing may reduce batch and assay variations, enable evaluation of rate-dependent drug effects, and facilitate the comparison of results obtained from hiPSC-CMs with those from adult human cardiomyocytes. As electrical stimulation (E-pacing) of hiPSC-CMs has not been validated with high-throughput assays, herein, we compared the responses of hiPSC-CMs exposed with classic cardiac ion channel blockers under spontaneous beating and E-pacing conditions utilizing microelectrode array technology. We found that compared with spontaneously beating hiPSC-CMs, E-pacing: (1) reduced overall assay variabilities, (2) showed limited changes of field potential duration to pacemaker channel block, (3) revealed reverse rate dependence of multiple ion channel blockers on field potential duration, and (4) eliminated the effects of sodium channel block on depolarization spike amplitude and spike slope due to a software error in acquiring depolarization spike at cardiac pacing mode. Microelectrode array optogenetic pacing and current clamp recordings at various stimulation frequencies demonstrated rate-dependent block of sodium channels in hiPSC-CMs as reported in adult cardiomyocytes. In conclusion, pacing enabled more accurate rate- and concentration-dependent drug effect evaluations. Analyzing responses of hiPSC-CMs under both spontaneously beating and rate-controlled conditions may help better assess the effects of test compounds on cardiac electrophysiology and evaluate the value of the hiPSC-CM model.
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Affiliation(s)
- Feng Wei
- Division of Systems Biology, National Center for Toxicological Research, Food and Drug Administration, Jefferson, Arkansas
- Department of Structural Heart Disease, The First Affiliated Hospital of Xi’an Jiaotong University, Xi’an, Shaanxi 710061, China
| | - Marc Pourrier
- IonsGate Preclinical Services Inc, Vancouver, British Columbia, Canada
| | - David G Strauss
- Division of Applied and Regulatory Science, Office of Clinical Pharmacology, Office of Translational Science, Center for Drug Evaluation and Research
| | - Norman Stockbridge
- Division of Cardiovascular and Renal Products, Office of New Drugs I, Center for Drug Evaluation and Research, Food and Drug Administration, Silver Spring, Maryland
| | - Li Pang
- Division of Systems Biology, National Center for Toxicological Research, Food and Drug Administration, Jefferson, Arkansas
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Burnett SD, Blanchette AD, Grimm FA, House JS, Reif DM, Wright FA, Chiu WA, Rusyn I. Population-based toxicity screening in human induced pluripotent stem cell-derived cardiomyocytes. Toxicol Appl Pharmacol 2019; 381:114711. [PMID: 31425687 PMCID: PMC6745256 DOI: 10.1016/j.taap.2019.114711] [Citation(s) in RCA: 35] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2019] [Revised: 08/06/2019] [Accepted: 08/14/2019] [Indexed: 11/23/2022]
Abstract
The potential for cardiotoxicity is carefully evaluated for pharmaceuticals, as it is a major safety liability. However, environmental chemicals are seldom tested for their cardiotoxic potential. Moreover, there is a large variability in both baseline and drug-induced cardiovascular risk in humans, but data are lacking on the degree to which susceptibility to chemically-induced cardiotoxicity may also vary. Human induced pluripotent stem cell (iPSC)-derived cardiomyocytes have become an important in vitro model for drug screening. Thus, we hypothesized that a population-based model of iPSC-derived cardiomyocytes from a diverse set of individuals can be used to assess potential hazard and inter-individual variability in chemical effects on these cells. We conducted concentration-response screening of 134 chemicals (pharmaceuticals, industrial and environmental chemicals and food constituents) in iPSC-derived cardiomyocytes from 43 individuals, comprising both sexes and diverse ancestry. We measured kinetic calcium flux and conducted high-content imaging following chemical exposure, and utilized a panel of functional and cytotoxicity parameters in concentration-response for each chemical and donor. We show reproducible inter-individual variability in both baseline and chemical-induced effects on iPSC-derived cardiomyocytes. Further, chemical-specific variability in potency and degree of population variability were quantified. This study shows the feasibility of using an organotypic population-based human in vitro model to quantitatively assess chemicals for which little cardiotoxicity information is available. Ultimately, these results advance in vitro toxicity testing methodologies by providing an innovative tool for population-based cardiotoxicity screening, contributing to the paradigm shift from traditional animal models of toxicity to in vitro toxicity testing methods.
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Affiliation(s)
- Sarah D Burnett
- Department of Veterinary Integrative Biosciences, Texas A&M University, College Station, TX 77843-4458, USA.
| | - Alexander D Blanchette
- Department of Veterinary Integrative Biosciences, Texas A&M University, College Station, TX 77843-4458, USA.
| | - Fabian A Grimm
- Department of Veterinary Integrative Biosciences, Texas A&M University, College Station, TX 77843-4458, USA.
| | - John S House
- Bioinformatics Research Center, North Carolina State University, Raleigh, NC 27695, USA.
| | - David M Reif
- Department of Biological Sciences, North Carolina State University, Raleigh, NC 27695, USA; Department of Statistics, North Carolina State University, Raleigh, NC 27695, USA
| | - Fred A Wright
- Department of Biological Sciences, North Carolina State University, Raleigh, NC 27695, USA; Department of Statistics, North Carolina State University, Raleigh, NC 27695, USA.
| | - Weihsueh A Chiu
- Department of Veterinary Integrative Biosciences, Texas A&M University, College Station, TX 77843-4458, USA.
| | - Ivan Rusyn
- Department of Veterinary Integrative Biosciences, Texas A&M University, College Station, TX 77843-4458, USA.
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25
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Pang L, Sager P, Yang X, Shi H, Sannajust F, Brock M, Wu JC, Abi-Gerges N, Lyn-Cook B, Berridge BR, Stockbridge N. Workshop Report: FDA Workshop on Improving Cardiotoxicity Assessment With Human-Relevant Platforms. Circ Res 2019; 125:855-867. [PMID: 31600125 DOI: 10.1161/circresaha.119.315378] [Citation(s) in RCA: 48] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Given that cardiovascular safety concerns remain the leading cause of drug attrition at the preclinical drug development stage, the National Center for Toxicological Research of the US Food and Drug Administration hosted a workshop to discuss current gaps and challenges in translating preclinical cardiovascular safety data to humans. This white paper summarizes the topics presented by speakers from academia, industry, and government intended to address the theme of improving cardiotoxicity assessment in drug development. The main conclusion is that to reduce cardiovascular safety liabilities of new therapeutic agents, there is an urgent need to integrate human-relevant platforms/approaches into drug development. Potential regulatory applications of human-derived cardiomyocytes and future directions in employing human-relevant platforms to fill the gaps and overcome barriers and challenges in preclinical cardiovascular safety assessment were discussed. This paper is intended to serve as an initial step in a public-private collaborative development program for human-relevant cardiotoxicity tools, particularly for cardiotoxicities characterized by contractile dysfunction or structural injury.
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Affiliation(s)
- Li Pang
- From the Division of Systems Biology, National Center for Toxicological Research, U.S. Food and Drug Administration (L.P.)
| | | | - Xi Yang
- Division of Cardiovascular and Renal Products, Center for Drug Evaluation and Research, U.S. Food and Drug Administration (X.Y.)
| | - Hong Shi
- Discovery Toxicology, Bristol-Myers Squibb (BMS) Company (H.S.)
| | - Frederick Sannajust
- Safety & Exploratory Pharmacology Department, SALAR Division, Merck & Co (F.S.)
| | | | - Joseph C Wu
- Stanford University School of Medicine, Stanford Cardiovascular Institute (J.C.W.)
| | | | - Beverly Lyn-Cook
- Division of Biochemical Toxicology, National Center for Toxicological Research, U.S. Food and Drug Administration (B.L.-C.)
| | - Brian R Berridge
- Division of the National Toxicology Program, National Institute of Environmental Health Sciences, National Institutes of Health (B.R.B.)
| | - Norman Stockbridge
- Division of Cardiovascular and Renal Products, Center for Drug Evaluation and Research, U.S. Food and Drug Administration (N.S.)
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26
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Lu HR, Zeng H, Kettenhofen R, Guo L, Kopljar I, van Ammel K, Tekle F, Teisman A, Zhai J, Clouse H, Pierson J, Furniss M, Lagrutta A, Sannajust F, Gallacher DJ. Assessing Drug-Induced Long QT and Proarrhythmic Risk Using Human Stem-Cell-Derived Cardiomyocytes in a Ca2+ Imaging Assay: Evaluation of 28 CiPA Compounds at Three Test Sites. Toxicol Sci 2019; 170:345-356. [PMID: 31020317 PMCID: PMC6657578 DOI: 10.1093/toxsci/kfz102] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
The goal of this research consortium including Janssen, MSD, Ncardia, FNCR/LBR, and Health and Environmental Sciences Institute (HESI) was to evaluate the utility of an additional in vitro assay technology to detect potential drug-induced long QT and torsade de pointes (TdP) risk by monitoring cytosolic free Ca2+ transients in human stem-cell-derived cardiomyocytes (hSC-CMs). The potential proarrhythmic risks of the 28 comprehensive in vitro proarrhythmia assay (CiPA) drugs linked to low, intermediate, and high clinical TdP risk were evaluated in a blinded manner using Ca2+-sensitive fluorescent dye assay recorded from a kinetic plate reader system (Hamamatsu FDSS/µCell and FDSS7000) in 2D cultures of 2 commercially available hSC-CM lines (Cor.4U and CDI iCell Cardiomyocytes) at 3 different test sites. The Ca2+ transient assay, performed at the 3 sites using the 2 different hSC-CMs lines, correctly detected potential drug-induced QT prolongation among the 28 CiPA drugs and detected cellular arrhythmias-like/early afterdepolarization in 7 of 8 high TdP-risk drugs (87.5%), 6 of 11 intermediate TdP-risk drugs (54.5%), and 0 of 9 low/no TdP-risk drugs (0%). The results were comparable among the 3 sites and from 2 hSC-CM cell lines. The Ca2+ transient assay can serve as a user-friendly and higher throughput alternative to complement the microelectrode array and voltage-sensing optical action potential recording assays used in the HESI-CiPA study for in vitro assessment of drug-induced long QT and TdP risk.
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Affiliation(s)
- Hua Rong Lu
- Janssen Pharmaceutica NV (J&J), 2340 Beerse, Belgium
| | - Haoyu Zeng
- Safety and Exploratory Pharmacology, Merck Sharp & Dohme Corp. (MSD), West Point, Pennsylvania
| | | | - Liang Guo
- Frederick National Laboratory for Cancer Research (FNLCR)/Leidos Biomedical Research (LBR), Inc., Frederick, Maryland 21702
| | - Ivan Kopljar
- Janssen Pharmaceutica NV (J&J), 2340 Beerse, Belgium
| | | | - Fetene Tekle
- Janssen Pharmaceutica NV (J&J), 2340 Beerse, Belgium
| | - Ard Teisman
- Janssen Pharmaceutica NV (J&J), 2340 Beerse, Belgium
| | - Jin Zhai
- Safety and Exploratory Pharmacology, Merck Sharp & Dohme Corp. (MSD), West Point, Pennsylvania
| | - Holly Clouse
- Safety and Exploratory Pharmacology, Merck Sharp & Dohme Corp. (MSD), West Point, Pennsylvania
| | - Jennifer Pierson
- HESI, Cardiac Safety Technical Committee, Washington, District of Columbia 20005
| | - Michael Furniss
- Frederick National Laboratory for Cancer Research (FNLCR)/Leidos Biomedical Research (LBR), Inc., Frederick, Maryland 21702
| | - Armando Lagrutta
- Safety and Exploratory Pharmacology, Merck Sharp & Dohme Corp. (MSD), West Point, Pennsylvania
| | - Frederick Sannajust
- Safety and Exploratory Pharmacology, Merck Sharp & Dohme Corp. (MSD), West Point, Pennsylvania
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27
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Vargas HM. "Thorough QT/QTc in a Dish": Can Human Induced Pluripotent Stem Cell-Derived Cardiomyocytes Predict Thorough QT Outcomes? Clin Pharmacol Ther 2019; 105:1064-1066. [PMID: 30844081 PMCID: PMC6593620 DOI: 10.1002/cpt.1384] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2018] [Accepted: 01/23/2019] [Indexed: 12/15/2022]
Affiliation(s)
- Hugo M Vargas
- Comparative Biology & Safety Sciences, Amgen, Inc., Thousand Oaks, California, USA
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