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Mariz CF, Nascimento JVG, Morais BS, Alves MKM, Rojas LAV, Zanardi-Lamardo E, Carvalho PSM. Toxicity of the oil spilled on the Brazilian coast at different degrees of natural weathering to early life stages of the zebrafish Danio rerio. MARINE POLLUTION BULLETIN 2024; 207:116819. [PMID: 39182410 DOI: 10.1016/j.marpolbul.2024.116819] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/18/2024] [Revised: 07/07/2024] [Accepted: 08/03/2024] [Indexed: 08/27/2024]
Abstract
Toxicity of water accommodated fractions (WAF) from the oil spilled on the Brazilian coast at different stages of weathering were investigated using Danio rerio. Weathering stages included emulsified oil that reached the coast (OM) and oil collected 50 days later deposited on beach sand (OS) or adhered to shore rocks (OR). Parent and alkylated naphthalenes decreased whereas phenanthrenes increased from less weathered WAF-OM to more weathered WAF-OS and WAF-OR. More weathered WAF-OS and WAF-OR were more potent inducers of zebrafish developmental delay, suggesting that parent and alkylated phenanthrenes are involved. However, less weathered WAF-OM was a more potent inducer of failure in swim-bladder inflation than more weathered WAF-OS and WAF-OR, suggesting that parent and alkylated naphthalenes are involved. Decreases in heart rates and increased heart and skeletal deformities were observed in exposed larvae. Lowest observed effect concentrations for different developmental toxicity endpoints are within environmentally relevant polycyclic aromatic hydrocarbon concentrations.
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Affiliation(s)
- Célio Freire Mariz
- Departamento de Zoologia, Universidade Federal de Pernambuco, Av. Prof. Moraes Rego, 1235, Cidade Universitária, Recife 50670-901, Brazil.
| | - João V Gomes Nascimento
- Departamento de Zoologia, Universidade Federal de Pernambuco, Av. Prof. Moraes Rego, 1235, Cidade Universitária, Recife 50670-901, Brazil
| | - Bruna Santana Morais
- Departamento de Zoologia, Universidade Federal de Pernambuco, Av. Prof. Moraes Rego, 1235, Cidade Universitária, Recife 50670-901, Brazil
| | - Maria K Melo Alves
- Departamento de Zoologia, Universidade Federal de Pernambuco, Av. Prof. Moraes Rego, 1235, Cidade Universitária, Recife 50670-901, Brazil
| | - Lino Angel Valcarcel Rojas
- Departamento de Oceanografia, Universidade Federal de Pernambuco, Av. Arquitetura s/n, Cidade Universitária, Recife 50740-550, Brazil
| | - Eliete Zanardi-Lamardo
- Departamento de Oceanografia, Universidade Federal de Pernambuco, Av. Arquitetura s/n, Cidade Universitária, Recife 50740-550, Brazil
| | - Paulo S M Carvalho
- Departamento de Zoologia, Universidade Federal de Pernambuco, Av. Prof. Moraes Rego, 1235, Cidade Universitária, Recife 50670-901, Brazil
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Zünkler BJ. Multiple hERG channel blocking pathways: implications for macromolecules. Trends Pharmacol Sci 2024; 45:671-677. [PMID: 39043501 DOI: 10.1016/j.tips.2024.06.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2024] [Revised: 06/21/2024] [Accepted: 06/23/2024] [Indexed: 07/25/2024]
Abstract
Numerous non-cardiovascular drugs have a potential to induce life-threatening torsades de pointes (TdP) ventricular cardiac arrhythmias by blocking human ether-à-go-go-related gene (hERG) currents via binding to the channel's inner cavity. Identification of the hERG current-inhibiting properties of candidate drugs is performed focusing on binding sites in the channel pore. It has been suggested that biologicals have a low likelihood of hERG current inhibition, since their poor diffusion across the plasma membrane prevents them from reaching the binding site in the channel pore. However, biologicals could influence hERG channel function by binding to 'unconventional' noncanonical binding sites. This Opinion gives an overview on noncanonical blockers of hERG channels that might be of relevance for the assessment of the possible torsadogenic potential of macromolecular therapeutics.
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Affiliation(s)
- Bernd J Zünkler
- Institute of Pharmacology, Toxicology and Clinical Pharmacy, Technische Universität Braunschweig, Mendelssohnstr. 1, 38106 Braunschweig, Germany.
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Sun P, Guo X, Ding E, Li C, Ren H, Xu Y, Qian J, Deng F, Shi W, Dong H, Lin EZ, Guo P, Fang J, Zhang Q, Zhao W, Tong S, Lu X, Pollitt KJG, Shi X, Tang S. Association between Personal Abiotic Airborne Exposures and Body Composition Changes among Healthy Adults (60-69 Years Old): A Combined Exposome-Wide and Lipidome Mediation Approach from the China BAPE Study. ENVIRONMENTAL HEALTH PERSPECTIVES 2024; 132:77005. [PMID: 39028628 PMCID: PMC11259245 DOI: 10.1289/ehp13865] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/22/2023] [Revised: 05/25/2024] [Accepted: 06/24/2024] [Indexed: 07/21/2024]
Abstract
BACKGROUND Evidence suggested that abiotic airborne exposures may be associated with changes in body composition. However, more evidence is needed to identify key pollutants linked to adverse health effects and their underlying biomolecular mechanisms, particularly in sensitive older adults. OBJECTIVES Our research aimed to systematically assess the relationship between abiotic airborne exposures and changes in body composition among healthy older adults, as well as the potential mediating mechanisms through the serum lipidome. METHODS From September 2018 to January 2019, we conducted a monthly survey among 76 healthy adults (60-69 years old) in the China Biomarkers of Air Pollutant Exposure (BAPE) study, measuring their personal exposures to 632 abiotic airborne pollutions using MicroPEM and the Fresh Air wristband, 18 body composition indicators from the InBody 770 device, and lipidomics from venous blood samples. We used an exposome-wide association study (ExWAS) and deletion/substitution/addition (DSA) model to unravel complex associations between exposure to contaminant mixtures and body composition, a Bayesian kernel machine regression (BKMR) model to assess the overall effect of key exposures on body composition, and mediation analysis to identify lipid intermediators. RESULTS The ExWAS and DSA model identified that 2,4,5-T methyl ester (2,4,5-TME), 9,10-Anthracenedione (ATQ), 4b,8-dimethyl-2-isopropylphenanthrene, and 4b,5,6,7,8,8a,9,10-octahydro-(DMIP) were associated with increased body fat mass (BFM), fat mass indicators (FMI), percent body fat (PBF), and visceral fat area (VFA) in healthy older adults [Bonferroni-Hochberg false discovery rate ( FD R BH ) < 0.05 ]. The BKMR model demonstrated a positive correlation between contaminants (anthracene, ATQ, copaene, di-epi-α -cedrene, and DMIP) with VFA. Mediation analysis revealed that phosphatidylcholine [PC, PC(16:1e/18:1), PC(16:2e/18:0)] and sphingolipid [SM, SM(d18:2/24:1)] mediated a significant portion, ranging from 12.27% to 26.03% (p-value < 0.05 ), of the observed increase in VFA. DISCUSSION Based on the evidence from multiple model results, ATQ and DMIP were statistically significantly associated with the increased VFA levels of healthy older adults, potentially regulated through lipid intermediators. These findings may have important implications for identifying potentially harmful environmental chemicals and developing targeted strategies for the control and prevention of chronic diseases in the future, particularly as the global population is rapidly aging. https://doi.org/10.1289/EHP13865.
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Affiliation(s)
- Peijie Sun
- China CDC Key Laboratory of Environment and Population Health, National Institute of Environmental Health, Chinese Center for Disease Control and Prevention, Beijing, China
- Department of Toxicology, School of Public Health, China Medical University, Shenyang, China
| | - Xiaojie Guo
- China CDC Key Laboratory of Environment and Population Health, National Institute of Environmental Health, Chinese Center for Disease Control and Prevention, Beijing, China
- Department of Epidemiology, School of Public Health, Southern Medical University, Guangzhou, Guangdong, China
| | - Enmin Ding
- China CDC Key Laboratory of Environment and Population Health, National Institute of Environmental Health, Chinese Center for Disease Control and Prevention, Beijing, China
- School of Population Medicine and Public Health, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
| | - Chenfeng Li
- China CDC Key Laboratory of Environment and Population Health, National Institute of Environmental Health, Chinese Center for Disease Control and Prevention, Beijing, China
- Department of Occupational Health and Environment Health, School of Public Health, Anhui Medical University, Hefei, Anhui, China
| | - Huimin Ren
- China CDC Key Laboratory of Environment and Population Health, National Institute of Environmental Health, Chinese Center for Disease Control and Prevention, Beijing, China
- Department of Toxicology, School of Public Health, China Medical University, Shenyang, China
| | - Yibo Xu
- China CDC Key Laboratory of Environment and Population Health, National Institute of Environmental Health, Chinese Center for Disease Control and Prevention, Beijing, China
- Department of Epidemiology, School of Public Health, China Medical University, Shenyang, China
| | - Jiankun Qian
- China CDC Key Laboratory of Environment and Population Health, National Institute of Environmental Health, Chinese Center for Disease Control and Prevention, Beijing, China
- Department of Toxicology, School of Public Health, China Medical University, Shenyang, China
| | - Fuchang Deng
- China CDC Key Laboratory of Environment and Population Health, National Institute of Environmental Health, Chinese Center for Disease Control and Prevention, Beijing, China
| | - Wanying Shi
- Department of Epidemiology and Health Statistics, School of Public Health, Capital Medical University, and Beijing Municipal Key Laboratory of Clinical Epidemiology, Beijing, China
| | - Haoran Dong
- China CDC Key Laboratory of Environment and Population Health, National Institute of Environmental Health, Chinese Center for Disease Control and Prevention, Beijing, China
| | - Elizabeth Z. Lin
- Department of Environmental Health Sciences, Yale School of Public Health, New Haven, Connecticut, USA
| | - Pengfei Guo
- Department of Environmental Health Sciences, Yale School of Public Health, New Haven, Connecticut, USA
| | - Jianlong Fang
- China CDC Key Laboratory of Environment and Population Health, National Institute of Environmental Health, Chinese Center for Disease Control and Prevention, Beijing, China
| | - Qian Zhang
- Chinese Center for Disease Control and Prevention, National Institute for Nutrition and Health, Beijing, China
| | - Wenhua Zhao
- Chinese Center for Disease Control and Prevention, National Institute for Nutrition and Health, Beijing, China
| | - Shilu Tong
- China CDC Key Laboratory of Environment and Population Health, National Institute of Environmental Health, Chinese Center for Disease Control and Prevention, Beijing, China
- School of Public Health and Social Work, Queensland University of Technology, Brisbane, Australia
| | - Xiaobo Lu
- Department of Toxicology, School of Public Health, China Medical University, Shenyang, China
| | - Krystal J. Godri Pollitt
- Department of Environmental Health Sciences, Yale School of Public Health, New Haven, Connecticut, USA
| | - Xiaoming Shi
- China CDC Key Laboratory of Environment and Population Health, National Institute of Environmental Health, Chinese Center for Disease Control and Prevention, Beijing, China
- National Key Laboratory of Intelligent Tracking and Forecasting for Infectious Diseases, National Institute of Environmental Health, Chinese Center for Disease Control and Prevention, Beijing, China
| | - Song Tang
- China CDC Key Laboratory of Environment and Population Health, National Institute of Environmental Health, Chinese Center for Disease Control and Prevention, Beijing, China
- Center for Global Health, School of Public Health, Nanjing Medical University, Nanjing, Jiangsu, China
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Filatova TS, Kuzmin VS, Dzhumaniiazova I, Pustovit OB, Abramochkin DV, Shiels HA. 3-Methyl-phenanthrene (3-MP) disrupts the electrical and contractile activity of the heart of the polar fish, navaga cod (Eleginus nawaga). CHEMOSPHERE 2024; 357:142089. [PMID: 38643846 DOI: 10.1016/j.chemosphere.2024.142089] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/02/2024] [Revised: 04/17/2024] [Accepted: 04/18/2024] [Indexed: 04/23/2024]
Abstract
Alkylated polycyclic aromatic hydrocarbons are abundant in crude oil and are enriched during petroleum refinement but knowledge of their cardiotoxicity remains limited. Polycyclic aromatic hydrocarbons (PAHs) are considered the main hazardous components in crude oil and the tricyclic PAH phenanthrene has been singled out for its direct effects on cardiac tissue in mammals and fish. Here we test the impact of the monomethylated phenanthrene, 3-methylphenanthrene (3-MP), on the contractile and electrical function of the atrium and ventricle of a polar fish, the navaga cod (Eleginus nawaga). Using patch-clamp electrophysiology in atrial and ventricular cardiomyocytes we show that 3-MP is a potent inhibitor of the delayed rectifier current IKr (IC50 = 0.25 μM) and prolongs ventricular action potential duration. Unlike the parent compound phenanthrene, 3-MP did not reduce the amplitude of the L-type Ca2+ current (ICa) but it accelerated current inactivation thus reducing charge transfer across the myocyte membrane and compromising pressure development of the whole heart. 3-MP was a potent inhibitor (IC50 = 4.7 μM) of the sodium current (INa), slowing the upstroke of the action potential in isolated cells, slowing conduction velocity across the atrium measured with optical mapping, and increasing atrio-ventricular delay in a working whole heart preparation. Together, these findings reveal the strong cardiotoxic potential of this phenanthrene derivative on the fish heart. As 3-MP and other alkylated phenanthrenes comprise a large fraction of the PAHs in crude oil mixtures, these findings are worrisome for Arctic species facing increasing incidence of spills and leaks from the petroleum industry. 3-MP is also a major component of polluted air but is not routinely measured. This is also of concern if the hearts of humans and other terrestrial animals respond to this PAH in a similar manner to fish.
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Affiliation(s)
- Tatiana S Filatova
- Department of Human and Animal Physiology, Lomonosov Moscow State University, Leninskiye Gory, 1, 12, Moscow, Russia
| | - Vladislav S Kuzmin
- Department of Human and Animal Physiology, Lomonosov Moscow State University, Leninskiye Gory, 1, 12, Moscow, Russia
| | - Irina Dzhumaniiazova
- Department of Human and Animal Physiology, Lomonosov Moscow State University, Leninskiye Gory, 1, 12, Moscow, Russia
| | - Oksana B Pustovit
- Department of Human and Animal Physiology, Lomonosov Moscow State University, Leninskiye Gory, 1, 12, Moscow, Russia
| | - Denis V Abramochkin
- Department of Human and Animal Physiology, Lomonosov Moscow State University, Leninskiye Gory, 1, 12, Moscow, Russia; Laboratory of Cardiac Electrophysiology, Chazov National Medical Research Center for Cardiology, Moscow, Russia; Department of Physiology, Pirogov Russian National Research Medical University, Ostrovityanova str., 1, Moscow, Russia
| | - Holly A Shiels
- Faculty of Biology, Medicine and Health, Core Technology Facility, 46 Grafton Street, University of Manchester, Manchester, M13 9NT, UK.
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5
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England E, Morris JW, Bussy C, Hancox JC, Shiels HA. The key characteristics of cardiotoxicity for the pervasive pollutant phenanthrene. JOURNAL OF HAZARDOUS MATERIALS 2024; 469:133853. [PMID: 38503207 DOI: 10.1016/j.jhazmat.2024.133853] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/31/2023] [Revised: 02/08/2024] [Accepted: 02/19/2024] [Indexed: 03/21/2024]
Abstract
The key characteristic (KCs) framework has been used previously to assess the carcinogenicity and cardiotoxicity of various chemical and pharmacological agents. Here, the 12 KCs of cardiotoxicity are used to evaluate the previously reported cardiotoxicity of phenanthrene (Phe), a tricyclic polycyclic aromatic hydrocarbon (PAH), and major component of fossil fuel-derived air pollution. Phe is a semi-volatile pollutant existing in both the gas phase and particle phase through adsorption onto or into particulate matter (PM). Phe can translocate across the airways and gastrointestinal tract into the systemic circulation, enabling body-wide effects. Our evaluation based on a comprehensive literature review, indicates Phe exhibits 11 of the 12 KCs for cardiotoxicity. These include adverse effects on cardiac electromechanical performance, the vasculature and endothelium, immunomodulation and oxidative stress, and neuronal and endocrine control. Environmental agents that have similarly damaging effects on the cardiovascular system are heavily regulated and monitored, yet globally there is no air quality regulation specific for PAHs like Phe. Environmental monitoring of Phe is not the international standard with benzo[a]pyrene being frequently used as a proxy despite the two PAH species exhibiting significant differences in sources, concentration variations and toxic effects. The evidence summarised in this evaluation highlights the need to move away from proxied PAH measurements and develop a monitoring network capable of measuring Phe concentration. It also stresses the need to raise awareness amongst the medical community of the potential cardiovascular impact of PAH exposure. This will allow the production of mitigation strategies and possibly the development of new policies for the protection of the societal groups most vulnerable to cardiovascular disease.
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Affiliation(s)
- E England
- Division of Cardiovascular Sciences, Faculty of Biology, Medicine and Health, The University of Manchester, Manchester, UK.
| | - J W Morris
- Division of Cardiovascular Sciences, Faculty of Biology, Medicine and Health, The University of Manchester, Manchester, UK.
| | - C Bussy
- Division of Immunology, Immunity to Infection, and Respiratory Medicine, Faculty of Biology, Medicine and Health, The University of Manchester, UK
| | - J C Hancox
- School of Physiology, Pharmacology and Neuroscience, University of Bristol, Bristol, UK
| | - H A Shiels
- Division of Cardiovascular Sciences, Faculty of Biology, Medicine and Health, The University of Manchester, Manchester, UK.
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Incardona JP, Linbo TL, Cameron JR, Scholz NL. Structure-activity relationships for alkyl-phenanthrenes support two independent but interacting synergistic models for PAC mixture potency. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 918:170544. [PMID: 38309367 DOI: 10.1016/j.scitotenv.2024.170544] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/21/2023] [Revised: 01/19/2024] [Accepted: 01/27/2024] [Indexed: 02/05/2024]
Abstract
Multiple lines of evidence at whole animal, cellular and molecular levels implicate polycyclic aromatic compounds (PACs) with three rings as drivers of crude oil toxicity to developing fish. Phenanthrene (P0) and its alkylated homologs (C1- through C4-phenanthrenes) comprise the most prominent subfraction of tricyclic PACs in crude oils. Among this family, P0 has been studied intensively, with more limited detail available for the C4-phenanthrene 1-methyl-7-isopropyl-phenanthrene (1-M,7-IP, or retene). While both compounds are cardiotoxic, P0 impacts embryonic cardiac function and development through direct blockade of K+ and Ca2+ currents that regulate cardiomyocyte contractions. In contrast, 1-M,7-IP dysregulates aryl hydrocarbon receptor (AHR) activation in developing ventricular cardiomyocytes. Although no other compounds have been assessed in detail across the larger family of alkylated phenanthrenes, increasing alkylation might be expected to shift phenanthrene family member activity from K+/Ca2+ ion current blockade to AHR activation. Using embryos of two distantly related fish species, zebrafish and Atlantic haddock, we tested 14 alkyl-phenanthrenes in both acute and latent developmental cardiotoxicity assays. All compounds were cardiotoxic, and effects were resolved into impacts on multiple, highly specific aspects of heart development or function. Craniofacial defects were clearly linked to developmental cardiotoxicity. Based on these findings, we suggest a novel framework to delineate the developmental toxicity of petrogenic PAC mixtures in fish, which incorporates multi-mechanistic pathways that produce interactive synergism at the organ level. In addition, relationships among measured embryo tissue concentrations, cytochrome P4501A mRNA induction, and cardiotoxic responses suggest a two-compartment toxicokinetic model that independently predicts high potency of PAC mixtures through classical metabolic synergism. These two modes of synergism, specific to the sub-fraction of phenanthrenes, are sufficient to explain the high embryotoxic potency of crude oils, independent of as-yet unmeasured compounds in these complex environmental mixtures.
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Affiliation(s)
- John P Incardona
- Environmental and Fisheries Science Division, Northwest Fisheries Science Center, National Marine Fisheries Service, NOAA Fisheries, Seattle, WA, USA.
| | - Tiffany L Linbo
- Environmental and Fisheries Science Division, Northwest Fisheries Science Center, National Marine Fisheries Service, NOAA Fisheries, Seattle, WA, USA
| | - James R Cameron
- Saltwater, Inc., Under Contract to Northwest Fisheries Science Center, National Oceanic and Atmospheric Administration, Seattle, WA, USA
| | - Nathaniel L Scholz
- Environmental and Fisheries Science Division, Northwest Fisheries Science Center, National Marine Fisheries Service, NOAA Fisheries, Seattle, WA, USA
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7
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McIntyre JK, Spromberg J, Cameron J, Incardona JP, Davis JW, Scholz NL. Bioretention filtration prevents acute mortality and reduces chronic toxicity for early life stage coho salmon (Oncorhynchus kisutch) episodically exposed to urban stormwater runoff. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 902:165759. [PMID: 37495136 DOI: 10.1016/j.scitotenv.2023.165759] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/08/2023] [Revised: 07/10/2023] [Accepted: 07/22/2023] [Indexed: 07/28/2023]
Abstract
As the human population of western North America continues to expand, widespread patterns of urban growth pose increasingly existential threats to certain wild stocks of Pacific salmon and steelhead (Oncorhynchus sp.). Rainfall previously absorbed into the soils of forests and grasslands falls instead on pavement and other hardened surfaces. This creates stormwater runoff that carries toxic metals, oil, and many other contaminants into salmon-bearing habitats. These include freshwater streams where coho salmon (O. kisutch) spawn in gravel beds. Coho salmon embryos develop within a thick eggshell (chorion) for weeks to months before hatching as alevins and ultimately emerging from the gravel as fry. Untreated urban runoff is highly toxic to older coho salmon (freshwater-resident juveniles and adult spawners), but the vulnerability of the earliest life stages remains poorly understood. To address this uncertainty, we fertilized eggs and raised them under an episodic stormwater exposure regimen, using runoff collected from a high-traffic arterial roadway from 15 discrete storm events. We monitored survival and morphological development, as well as molecular markers for contaminant exposure and cardiovascular stress. We also evaluated the benefit of treating runoff with green infrastructure (bioretention filtration) on coho salmon health and survival. Untreated runoff caused subtle sublethal toxicity in pre-hatch embryos with no mortality, followed by high rates of mortality from exposure at hatch. Bioretention filtration removed most measured contaminants (bacteria, dissolved metals, and polycyclic aromatic hydrocarbons), and the treated effluent was considerably less toxic - notably preventing mortality at the alevin stage. Our findings indicate that untreated urban runoff poses an important threat to early life stage coho salmon, in terms of both acute and delayed-in-time mortality. Moreover, while inexpensive management strategies involving bioinfiltration are promising, future green infrastructure effectiveness research should emphasize sublethal metrics for contaminant exposure and adverse health outcomes in salmonids.
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Affiliation(s)
- Jenifer K McIntyre
- Washington State University, School of the Environment, Puyallup Research and Extension Center, 2606 W Pioneer Ave, Puyallup, WA 98371, USA.
| | - Julann Spromberg
- Northwest Fisheries Science Center, National Marine Fisheries Service, National Oceanic and Atmospheric Administration, 2725 Montlake Blvd. E., Seattle, WA 98112, USA
| | - James Cameron
- Saltwater Inc, under contract to Northwest Fisheries Science Center, National Marine Fisheries Service, National Oceanic and Atmospheric Administration, 2725 Montlake Blvd. E., Seattle, WA 98112, USA
| | - John P Incardona
- Northwest Fisheries Science Center, National Marine Fisheries Service, National Oceanic and Atmospheric Administration, 2725 Montlake Blvd. E., Seattle, WA 98112, USA
| | - Jay W Davis
- United States Fish and Wildlife Service, Environmental Contaminants Program, 510 Desmond Dr. SE, Lacey, WA 98503, USA
| | - Nathaniel L Scholz
- Northwest Fisheries Science Center, National Marine Fisheries Service, National Oceanic and Atmospheric Administration, 2725 Montlake Blvd. E., Seattle, WA 98112, USA
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Furutani K. Facilitation of hERG Activation by Its Blocker: A Mechanism to Reduce Drug-Induced Proarrhythmic Risk. Int J Mol Sci 2023; 24:16261. [PMID: 38003453 PMCID: PMC10671758 DOI: 10.3390/ijms242216261] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2023] [Revised: 11/08/2023] [Accepted: 11/12/2023] [Indexed: 11/26/2023] Open
Abstract
Modulation of the human Ether-à-go-go-Related Gene (hERG) channel, a crucial voltage-gated potassium channel in the repolarization of action potentials in ventricular myocytes of the heart, has significant implications on cardiac electrophysiology and can be either antiarrhythmic or proarrhythmic. For example, hERG channel blockade is a leading cause of long QT syndrome and potentially life-threatening arrhythmias, such as torsades de pointes. Conversely, hERG channel blockade is the mechanism of action of Class III antiarrhythmic agents in terminating ventricular tachycardia and fibrillation. In recent years, it has been recognized that less proarrhythmic hERG blockers with clinical potential or Class III antiarrhythmic agents exhibit, in addition to their hERG-blocking activity, a second action that facilitates the voltage-dependent activation of the hERG channel. This facilitation is believed to reduce the proarrhythmic potential by supporting the final repolarizing of action potentials. This review covers the pharmacological characteristics of hERG blockers/facilitators, the molecular mechanisms underlying facilitation, and their clinical significance, as well as unresolved issues and requirements for research in the fields of ion channel pharmacology and drug-induced arrhythmias.
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Affiliation(s)
- Kazuharu Furutani
- Department of Pharmacology, Faculty of Pharmaceutical Sciences, Tokushima Bunri University, 180 Nishihama-Boji, Yamashiro-cho, Tokushima 770-8514, Japan
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Yaar S, Filatova TS, England E, Kompella SN, Hancox JC, Bechtold DA, Venetucci L, Abramochkin DV, Shiels HA. Global Air Pollutant Phenanthrene and Arrhythmic Outcomes in a Mouse Model. ENVIRONMENTAL HEALTH PERSPECTIVES 2023; 131:117002. [PMID: 37909723 PMCID: PMC10619431 DOI: 10.1289/ehp12775] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/20/2023] [Revised: 09/19/2023] [Accepted: 09/25/2023] [Indexed: 11/03/2023]
Abstract
BACKGROUND The three-ringed polycyclic aromatic hydrocarbon (PAH) phenanthrene (Phe) has been implicated in the cardiotoxicity of petroleum-based pollution in aquatic systems, where it disrupts the contractile and electrical function of the fish heart. Phe is also found adsorbed to particulate matter and in the gas phase of air pollution, but to date, no studies have investigated the impact of Phe on mammalian cardiac function. OBJECTIVES Our objectives were to determine the arrhythmogenic potential of acute Phe exposure on mammalian cardiac function and define the underlying mechanisms to provide insight into the toxicity risk to humans. METHODS Ex vivo Langendorff-perfused mouse hearts were used to test the arrhythmogenic potential of Phe on myocardial function, and voltage- and current-clamp recordings were used to define underlying cellular mechanisms in isolated cardiomyocytes. RESULTS Mouse hearts exposed to ∼ 8 μ M Phe for 15-min exhibited a significantly slower heart rate (p = 0.0006 , N = 10 hearts), a prolonged PR interval (p = 0.036 , N = 8 hearts), and a slower conduction velocity (p = 0.0143 , N = 7 hearts). Whole-cell recordings from isolated cardiomyocytes revealed action potential (AP) duration prolongation (at 80% repolarization; p = 0.0408 , n = 9 cells) and inhibition of key murine repolarizing currents-transient outward potassium current (I to ) and ultrarapid potassium current (I Kur )-following Phe exposure. A significant reduction in AP upstroke velocity (p = 0.0445 , n = 9 cells) and inhibition of the fast sodium current (I Na ; p = 0.001 , n = 8 cells) and calcium current (I Ca ; p = 0.0001 ) were also observed, explaining the slowed conduction velocity in intact hearts. Finally, acute exposure to ∼ 8 μ M Phe significantly increased susceptibility to arrhythmias (p = 0.0455 , N = 9 hearts). DISCUSSION To the best of our knowledge, this is the first evidence of direct inhibitory effects of Phe on mammalian cardiac electrical activity at both the whole-heart and cell levels. This electrical dysfunction manifested as an increase in arrhythmia susceptibility due to impairment of both conduction and repolarization. Similar effects in humans could have serious health consequences, warranting greater regulatory attention and toxicological investigation into this ubiquitous PAH pollutant generated from fossil-fuel combustion. https://doi.org/10.1289/EHP12775.
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Affiliation(s)
- Sana Yaar
- Faculty of Biology, Medicine, and Health, Division of Cardiovascular Sciences, University of Manchester, Manchester, UK
| | - Tatiana S. Filatova
- Department of Human and Animal Physiology, Lomonosov Moscow State University, Moscow, Russia
| | - Ellie England
- Faculty of Biology, Medicine, and Health, Division of Cardiovascular Sciences, University of Manchester, Manchester, UK
| | - Shiva N. Kompella
- Faculty of Biology, Medicine, and Health, Division of Cardiovascular Sciences, University of Manchester, Manchester, UK
| | - Jules C. Hancox
- School of Physiology, Pharmacology and Neuroscience, University of Bristol, Bristol, UK
| | - David A. Bechtold
- Faculty of Biology, Medicine, and Health, Division of Cardiovascular Sciences, University of Manchester, Manchester, UK
| | - Luigi Venetucci
- Faculty of Biology, Medicine, and Health, Division of Cardiovascular Sciences, University of Manchester, Manchester, UK
| | - Denis V. Abramochkin
- Department of Human and Animal Physiology, Lomonosov Moscow State University, Moscow, Russia
| | - Holly A. Shiels
- Faculty of Biology, Medicine, and Health, Division of Cardiovascular Sciences, University of Manchester, Manchester, UK
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Abramochkin DV, Filatova TS, Kuzmin VS, Voronkov YI, Kamkin A, Shiels HA. Tricyclic hydrocarbon fluorene attenuates ventricular ionic currents and pressure development in the navaga cod. Comp Biochem Physiol C Toxicol Pharmacol 2023; 273:109736. [PMID: 37659611 DOI: 10.1016/j.cbpc.2023.109736] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/27/2023] [Revised: 08/22/2023] [Accepted: 08/30/2023] [Indexed: 09/04/2023]
Abstract
The release of polycyclic aromatic hydrocarbons (PAHs) into the environment due to oil and diesel fuel spills is a serious threat to Arctic fish populations. PAHs produce multiple toxic effects in fish, but disturbance of electrical and contractile activity of the heart seems to be the most negative effect. Our study focused on the effects of fluorene, a tricyclic PAH resembling the well-investigated tricyclic phenanthrene, on major ionic currents and action potential (AP) waveform in isolated ventricular myocytes and on contractile activity in isolated whole hearts of polar navaga cod (Eleginus nawaga). Among the studied currents, the repolarizing rapid delayed rectifier K+ current IKr demonstrated the highest sensitivity to fluorene with IC50 of 0.54 μM. The depolarizing inward currents, INa and ICaL, were inhibited with 10 μM fluorene by 20.2 ± 2.8 % and 27.9 ± 8.4 %, respectively, thereby being much less sensitive to fluorene than IKr. Inward rectifier IK1 current was insensitive to fluorene (up to 10 μM). While 3 μM fluorene prolonged APs, 10 μM also slowed the AP upstroke. Resting membrane potential was not affected by any tested concentrations. In isolated heart experiments 10 μM fluorene caused modest depression of ventricular contractile activity. Thus, we have demonstrated that fluorene, a tricyclic PAH present in high quantities in crude oil, strongly impacts electrical activity with only slight effects on contractile activity in the heart of the polar fish, the navaga cod.
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Affiliation(s)
- Denis V Abramochkin
- Department of Biology, MSU-BIT University, Shenzhen, Guangdong Province, China; Department of Human and Animal Physiology, Lomonosov Moscow State University, Leninskiye Gory, 1, 12, Moscow, Russia.
| | - Tatiana S Filatova
- Department of Human and Animal Physiology, Lomonosov Moscow State University, Leninskiye Gory, 1, 12, Moscow, Russia
| | - Vladislav S Kuzmin
- Department of Human and Animal Physiology, Lomonosov Moscow State University, Leninskiye Gory, 1, 12, Moscow, Russia; Laboratory of Cardiac Electrophysiology, Chazov National Medical Research Center for Cardiology, Moscow, Russia
| | - Yuri I Voronkov
- State Research Center of the Russian Federation, Institute of Biomedical Problems, Russian Academy of Sciences, Moscow, Russia
| | - Andre Kamkin
- Department of Physiology, Pirogov Russian National Research Medical University, Ostrovityanova str., 1, Moscow, Russia
| | - Holly A Shiels
- Faculty of Biology, Medicine and Health, Core Technology Facility, 46 Grafton Street, University of Manchester, Manchester M13 9NT, UK
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11
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Helliwell MV, Zhang Y, El Harchi A, Dempsey CE, Hancox JC. Inhibition of the hERG Potassium Channel by a Methanesulphonate-Free E-4031 Analogue. Pharmaceuticals (Basel) 2023; 16:1204. [PMID: 37765012 PMCID: PMC10536391 DOI: 10.3390/ph16091204] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2023] [Revised: 08/15/2023] [Accepted: 08/17/2023] [Indexed: 09/29/2023] Open
Abstract
hERG (human Ether-à-go-go Related Gene)-encoded potassium channels underlie the cardiac rapid delayed rectifier (IKr) potassium current, which is a major target for antiarrhythmic agents and diverse non-cardiac drugs linked to the drug-induced form of long QT syndrome. E-4031 is a high potency hERG channel inhibitor from the methanesulphonanilide drug family. This study utilized a methanesulphonate-lacking E-4031 analogue, "E-4031-17", to evaluate the role of the methanesulphonamide group in E-4031 inhibition of hERG. Whole-cell patch-clamp measurements of the hERG current (IhERG) were made at physiological temperature from HEK 293 cells expressing wild-type (WT) and mutant hERG constructs. For E-4031, WT IhERG was inhibited by a half-maximal inhibitory concentration (IC50) of 15.8 nM, whilst the comparable value for E-4031-17 was 40.3 nM. Both compounds exhibited voltage- and time-dependent inhibition, but they differed in their response to successive applications of a long (10 s) depolarisation protocol, consistent with greater dissociation of E-4031-17 than the parent compound between applied commands. Voltage-dependent inactivation was left-ward voltage shifted for E-4031 but not for E-4031-17; however, inhibition by both compounds was strongly reduced by attenuated-inactivation mutations. Mutations of S6 and S5 aromatic residues (F656V, Y652A, F557L) greatly attenuated actions of both drugs. The S624A mutation also reduced IhERG inhibition by both molecules. Overall, these results demonstrate that the lack of a methanesulphonate in E-4031-17 is not an impediment to high potency inhibition of IhERG.
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Affiliation(s)
- Matthew V. Helliwell
- School of Biochemistry, Biomedical Sciences Building, University Walk, University of Bristol, Bristol BS8 1TD, UK; (M.V.H.); (C.E.D.)
- School of Physiology, Pharmacology and Neuroscience, Biomedical Sciences Building, University Walk, University of Bristol, Bristol BS8 1TD, UK; (Y.Z.); (A.E.H.)
| | - Yihong Zhang
- School of Physiology, Pharmacology and Neuroscience, Biomedical Sciences Building, University Walk, University of Bristol, Bristol BS8 1TD, UK; (Y.Z.); (A.E.H.)
| | - Aziza El Harchi
- School of Physiology, Pharmacology and Neuroscience, Biomedical Sciences Building, University Walk, University of Bristol, Bristol BS8 1TD, UK; (Y.Z.); (A.E.H.)
| | - Christopher E. Dempsey
- School of Biochemistry, Biomedical Sciences Building, University Walk, University of Bristol, Bristol BS8 1TD, UK; (M.V.H.); (C.E.D.)
| | - Jules C. Hancox
- School of Physiology, Pharmacology and Neuroscience, Biomedical Sciences Building, University Walk, University of Bristol, Bristol BS8 1TD, UK; (Y.Z.); (A.E.H.)
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12
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Wu Y, Qu W, Qiu C, Chen K, Zhuang Y, Zeng Z, Yan Y, Gu Y, Tao W, Gao J, Li K. The Method and Study of Detecting Phenanthrene in Seawater Based on a Carbon Nanotube-Chitosan Oligosaccharide Modified Electrode Immunosensor. Molecules 2023; 28:5701. [PMID: 37570671 PMCID: PMC10420227 DOI: 10.3390/molecules28155701] [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: 07/03/2023] [Revised: 07/21/2023] [Accepted: 07/24/2023] [Indexed: 08/13/2023] Open
Abstract
Phenanthrene (PHE), as a structurally simple, tricyclic, polycyclic aromatic hydrocarbon (PAHs), is widely present in marine environments and organisms, with serious ecological and health impacts. It is crucial to study fast and simple high-sensitivity detection methods for phenanthrene in seawater for the environment and the human body. In this paper, a immunosensor was prepared by using a multi-wall carbon nanotube (MWCNTs)-chitosan oligosaccharide (COS) nanocomposite membrane loaded with phenanthrene antibody. The principle was based on the antibody-antigen reaction in the immune reaction, using the strong electron transfer ability of multi-walled carbon nanotubes, coupled with chitosan oligosaccharides with an excellent film formation and biocompatibility, to amplify the detection signal. The content of the phenanthrene in seawater was studied via differential pulse voltammetry (DPV) using a potassium ferricyanide system as a redox probe. The antibody concentration, pH value, and probe concentration were optimized. Under the optimal experimental conditions, the response peak current of the phenanthrene was inversely proportional to the concentration of phenanthrene, in the range from 0.5 ng·mL-1 to 80 ng·mL-1, and the detection limit was 0.30 ng·mL-1. The immune sensor was successfully applied to the detection of phenanthrene in marine water, with a recovery rate of 96.1~101.5%, and provided a stable, sensitive, and accurate method for the real-time monitoring of marine environments.
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Affiliation(s)
- Yuxuan Wu
- College of Mechanical, Naval Architecture & Ocean Engineering, Beibu Gulf University, Qinzhou 535011, China; (Y.W.); (C.Q.); (K.C.); (Y.Z.); (Z.Z.); (Y.Y.); (Y.G.); (W.T.); (J.G.); (K.L.)
| | - Wei Qu
- Eastern Michigan Associated Engineering College, Beibu Gulf University, Qinzhou 535011, China
- College of Electronics and Information Engineering, Beibu Gulf University, Qinzhou 535011, China
- Guangxi Key Laboratory of Ocean Engineering Equipment and Technology, Qinzhou 535011, China
| | - Chengjun Qiu
- College of Mechanical, Naval Architecture & Ocean Engineering, Beibu Gulf University, Qinzhou 535011, China; (Y.W.); (C.Q.); (K.C.); (Y.Z.); (Z.Z.); (Y.Y.); (Y.G.); (W.T.); (J.G.); (K.L.)
- Guangxi Key Laboratory of Ocean Engineering Equipment and Technology, Qinzhou 535011, China
| | - Kaixuan Chen
- College of Mechanical, Naval Architecture & Ocean Engineering, Beibu Gulf University, Qinzhou 535011, China; (Y.W.); (C.Q.); (K.C.); (Y.Z.); (Z.Z.); (Y.Y.); (Y.G.); (W.T.); (J.G.); (K.L.)
| | - Yuan Zhuang
- College of Mechanical, Naval Architecture & Ocean Engineering, Beibu Gulf University, Qinzhou 535011, China; (Y.W.); (C.Q.); (K.C.); (Y.Z.); (Z.Z.); (Y.Y.); (Y.G.); (W.T.); (J.G.); (K.L.)
| | - Zexi Zeng
- College of Mechanical, Naval Architecture & Ocean Engineering, Beibu Gulf University, Qinzhou 535011, China; (Y.W.); (C.Q.); (K.C.); (Y.Z.); (Z.Z.); (Y.Y.); (Y.G.); (W.T.); (J.G.); (K.L.)
| | - Yirou Yan
- College of Mechanical, Naval Architecture & Ocean Engineering, Beibu Gulf University, Qinzhou 535011, China; (Y.W.); (C.Q.); (K.C.); (Y.Z.); (Z.Z.); (Y.Y.); (Y.G.); (W.T.); (J.G.); (K.L.)
| | - Yang Gu
- College of Mechanical, Naval Architecture & Ocean Engineering, Beibu Gulf University, Qinzhou 535011, China; (Y.W.); (C.Q.); (K.C.); (Y.Z.); (Z.Z.); (Y.Y.); (Y.G.); (W.T.); (J.G.); (K.L.)
| | - Wei Tao
- College of Mechanical, Naval Architecture & Ocean Engineering, Beibu Gulf University, Qinzhou 535011, China; (Y.W.); (C.Q.); (K.C.); (Y.Z.); (Z.Z.); (Y.Y.); (Y.G.); (W.T.); (J.G.); (K.L.)
| | - Jiaqi Gao
- College of Mechanical, Naval Architecture & Ocean Engineering, Beibu Gulf University, Qinzhou 535011, China; (Y.W.); (C.Q.); (K.C.); (Y.Z.); (Z.Z.); (Y.Y.); (Y.G.); (W.T.); (J.G.); (K.L.)
| | - Ke Li
- College of Mechanical, Naval Architecture & Ocean Engineering, Beibu Gulf University, Qinzhou 535011, China; (Y.W.); (C.Q.); (K.C.); (Y.Z.); (Z.Z.); (Y.Y.); (Y.G.); (W.T.); (J.G.); (K.L.)
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13
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Sørhus E, Nakken CL, Donald CE, Ripley DM, Shiels HA, Meier S. Cardiac toxicity of phenanthrene depends on developmental stage in Atlantic cod (Gadus morhua). THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 881:163484. [PMID: 37068678 DOI: 10.1016/j.scitotenv.2023.163484] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/02/2022] [Revised: 03/16/2023] [Accepted: 04/09/2023] [Indexed: 06/01/2023]
Abstract
Complex mixtures like crude oil, and single components such as Phenanthrene (Phe), induce cardiotoxicity by interfering with excitation-contraction coupling. However, recent work has demonstrated that the timing of pollutant exposure during embryogenesis greatly impacts the degree of cardiac dysfunction caused. Here, we aimed to clarify the temporal dependence of Phe toxicity and the downstream effects of cardiac dysfunction using Atlantic cod (Gadus morhua). Phe (nominal concentration, 1.12 μmol/L), or the L-type‑calcium channel blocker Nicardipine (Nic) (nominal concentration, 2 and 4 μmol/L), were individually applied to cod embryos either during cardiogenesis (early) or after the onset of cardiac function (late). Phe toxicity was highly dependent on the timing of exposure. Exposure after the onset of cardiac function (i.e. late) caused more severe cardiac and extracardiac abnormalities at 3 days post hatching (dph) than early exposure. Late Phe exposure resulted in a smaller ventricle, eliminated ventricular contraction, and reduced atrial contraction. In contrast, early Phe exposure did not have an effect on cardiac development and function. This temporal difference was not as evident in the Nic treatment. Early Nic exposure created similar morphological phenotypes to the late Phe exposure. The two treatments (early Nic and late Phe) also shared a cardiofunctional phenotype, comprised of eliminated ventricular, and reduced atrial, contraction. These data suggest that extracardiac abnormalities, such as the craniofacial deformities seen after late embryonic exposure to cardiotoxic oil components and mixtures, are mostly downstream effects of cardiac dysfunction.
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Affiliation(s)
- Elin Sørhus
- Institute of Marine Research, Department of Marine Toxicology, Bergen, Norway.
| | | | - Carey E Donald
- Institute of Marine Research, Department of Marine Toxicology, Bergen, Norway
| | - Daniel M Ripley
- University of Manchester, Division of Cardiovascular Sciences, United Kingdom of Great Britain and Northern Ireland
| | - Holly A Shiels
- University of Manchester, Division of Cardiovascular Sciences, United Kingdom of Great Britain and Northern Ireland
| | - Sonnich Meier
- Institute of Marine Research, Department of Marine Toxicology, Bergen, Norway
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AlRawashdeh S, Chandrasekaran S, Barakat KH. Structural analysis of hERG channel blockers and the implications for drug design. J Mol Graph Model 2023; 120:108405. [PMID: 36680816 DOI: 10.1016/j.jmgm.2023.108405] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2022] [Revised: 12/26/2022] [Accepted: 01/09/2023] [Indexed: 01/13/2023]
Abstract
The repolarizing current (Ikr) produced by the hERG potassium channel forms a major component of the cardiac action potential and blocking this current by small molecule drugs can lead to life-threatening cardiotoxicity. Understanding the mechanisms of drug-mediated hERG inhibition is essential to develop a second generation of safe drugs, with minimal cardiotoxic effects. Although various computational tools and drug design guidelines have been developed to avoid binding of drugs to the hERG pore domain, there are many other aspects that are still open for investigation. This includes the use computational modelling to study the implications of hERG mutations on hERG structure and trafficking, the interactions of hERG with hERG chaperone proteins and with membrane-soluble molecules, the mechanisms of drugs that inhibit hERG trafficking and drugs that rescue hERG mutations. The plethora of available experimental data regarding all these aspects can guide the construction of much needed robust computational structural models to study these mechanisms for the rational design of safe drugs.
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Affiliation(s)
- Sara AlRawashdeh
- Faculty of Pharmacy and Pharmaceutical Sciences, University of Alberta, Edmonton, AB, Canada
| | | | - Khaled H Barakat
- Faculty of Pharmacy and Pharmaceutical Sciences, University of Alberta, Edmonton, AB, Canada.
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