1
|
Farm HJ, Clerx M, Cooper F, Polonchuk L, Wang K, Gavaghan DJ, Lei CL. Importance of modelling hERG binding in predicting drug-induced action potential prolongations for drug safety assessment. Front Pharmacol 2023; 14:1110555. [PMID: 37021055 PMCID: PMC10067903 DOI: 10.3389/fphar.2023.1110555] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2022] [Accepted: 02/22/2023] [Indexed: 03/30/2023] Open
Abstract
Reduction of the rapid delayed rectifier potassium current (IKr) via drug binding to the human Ether-à-go-go-Related Gene (hERG) channel is a well recognised mechanism that can contribute to an increased risk of Torsades de Pointes. Mathematical models have been created to replicate the effects of channel blockers, such as reducing the ionic conductance of the channel. Here, we study the impact of including state-dependent drug binding in a mathematical model of hERG when translating hERG inhibition to action potential changes. We show that the difference in action potential predictions when modelling drug binding of hERG using a state-dependent model versus a conductance scaling model depends not only on the properties of the drug and whether the experiment achieves steady state, but also on the experimental protocols. Furthermore, through exploring the model parameter space, we demonstrate that the state-dependent model and the conductance scaling model generally predict different action potential prolongations and are not interchangeable, while at high binding and unbinding rates, the conductance scaling model tends to predict shorter action potential prolongations. Finally, we observe that the difference in simulated action potentials between the models is determined by the binding and unbinding rate, rather than the trapping mechanism. This study demonstrates the importance of modelling drug binding and highlights the need for improved understanding of drug trapping which can have implications for the uses in drug safety assessment.
Collapse
Affiliation(s)
- Hui Jia Farm
- Department of Computer Science, University of Oxford, Oxford, United Kingdom
| | - Michael Clerx
- Centre for Mathematical Medicine and Biology, School of Mathematical Sciences, University of Nottingham, Nottingham, United Kingdom
| | - Fergus Cooper
- Doctoral Training Centre, University of Oxford, Oxford, United Kingdom
| | - Liudmila Polonchuk
- Roche Pharma Research and Early Development, Pharmaceutical Sciences, Roche Innovation Center Basel, F. Hoffmann-La Roche Ltd., Basel, Switzerland
| | - Ken Wang
- Roche Pharma Research and Early Development, Pharmaceutical Sciences, Roche Innovation Center Basel, F. Hoffmann-La Roche Ltd., Basel, Switzerland
| | - David J. Gavaghan
- Department of Computer Science, University of Oxford, Oxford, United Kingdom
- Doctoral Training Centre, University of Oxford, Oxford, United Kingdom
- *Correspondence: David J. Gavaghan, ; Chon Lok Lei,
| | - Chon Lok Lei
- Institute of Translational Medicine, Faculty of Health Sciences, University of Macau, Macau, China
- Department of Biomedical Sciences, Faculty of Health Sciences, University of Macau, Macau, China
- *Correspondence: David J. Gavaghan, ; Chon Lok Lei,
| |
Collapse
|
2
|
Translating the measurement of hERG kinetics and drug block for CiPA to a high throughput platform. J Pharmacol Toxicol Methods 2022; 117:107192. [PMID: 35750310 DOI: 10.1016/j.vascn.2022.107192] [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: 03/09/2022] [Revised: 06/13/2022] [Accepted: 06/16/2022] [Indexed: 11/23/2022]
Abstract
The Comprehensive in vitro Proarrhythmic Assay (CiPA) has promoted use of in silico models of drug effects on cardiac repolarization to improve proarrhythmic risk prediction. These models contain a pharmacodynamic component describing drug binding to hERG channels that required in vitro data for kinetics of block, in addition to potency, to constrain them. To date, development and validation has been undertaken using data from manual patch-clamp. The application of this approach at scale requires the development of a high-throughput, automated patch-clamp (APC) implementation. Here, we present a comprehensive analysis of the implementation of the Milnes, or CiPA dynamic protocol, on an APC platform, including quality control and data analysis. Kinetics and potency of block were assessed for bepridil, cisapride, terfenadine and verapamil with data retention/QC pass rate of 21.8% overall, or as high as 50.4% when only appropriate sweep lengths were considered for drugs with faster kinetics. The variability in IC50 and kinetics between manual and APC was comparable to that seen between sites/platforms in previous APC studies of potency. Whilst the experimental success is less than observed in screens of potency alone, it is still significantly greater than manual patch. With the modifications to protocol design, including sweep length, number of repetitions, and leak correction recommended in this study, this protocol can be applied on APC to acquire data comparable to manual patch clamp.
Collapse
|
3
|
Pesti K, Földi MC, Zboray K, Toth AV, Lukacs P, Mike A. Characterization of Compound-Specific, Concentration-Independent Biophysical Properties of Sodium Channel Inhibitor Mechanism of Action Using Automated Patch-Clamp Electrophysiology. Front Pharmacol 2021; 12:738460. [PMID: 34497526 PMCID: PMC8419314 DOI: 10.3389/fphar.2021.738460] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2021] [Accepted: 08/10/2021] [Indexed: 01/15/2023] Open
Abstract
We have developed an automated patch-clamp protocol that allows high information content screening of sodium channel inhibitor compounds. We have observed that individual compounds had their specific signature patterns of inhibition, which were manifested irrespective of the concentration. Our aim in this study was to quantify these properties. Primary biophysical data, such as onset rate, the shift of the half inactivation voltage, or the delay of recovery from inactivation, are concentration-dependent. We wanted to derive compound-specific properties, therefore, we had to neutralize the effect of concentration. This study describes how this is done, and shows how compound-specific properties reflect the mechanism of action, including binding dynamics, cooperativity, and interaction with the membrane phase. We illustrate the method using four well-known sodium channel inhibitor compounds, riluzole, lidocaine, benzocaine, and bupivacaine. Compound-specific biophysical properties may also serve as a basis for deriving parameters for kinetic modeling of drug action. We discuss how knowledge about the mechanism of action may help to predict the frequency-dependence of individual compounds, as well as their potential persistent current component selectivity. The analysis method described in this study, together with the experimental protocol described in the accompanying paper, allows screening for inhibitor compounds with specific kinetic properties, or with specific mechanisms of inhibition.
Collapse
Affiliation(s)
- Krisztina Pesti
- Department of Biochemistry, ELTE Eötvös Loránd University, Budapest, Hungary
- School of Ph.D. Studies, Semmelweis University, Budapest, Hungary
| | - Mátyás C. Földi
- Department of Biochemistry, ELTE Eötvös Loránd University, Budapest, Hungary
- Plant Protection Institute, Centre for Agricultural Research, Martonvásár, Hungary
| | - Katalin Zboray
- Plant Protection Institute, Centre for Agricultural Research, Martonvásár, Hungary
| | - Adam V. Toth
- Department of Biochemistry, ELTE Eötvös Loránd University, Budapest, Hungary
- Plant Protection Institute, Centre for Agricultural Research, Martonvásár, Hungary
| | - Peter Lukacs
- Department of Biochemistry, ELTE Eötvös Loránd University, Budapest, Hungary
- Plant Protection Institute, Centre for Agricultural Research, Martonvásár, Hungary
| | - Arpad Mike
- Department of Biochemistry, ELTE Eötvös Loránd University, Budapest, Hungary
- Plant Protection Institute, Centre for Agricultural Research, Martonvásár, Hungary
| |
Collapse
|
4
|
Exploring the inhibitory potentials of Momordica charantia bioactive compounds against Keap1-Kelch protein using computational approaches. In Silico Pharmacol 2021; 9:39. [PMID: 34249600 DOI: 10.1007/s40203-021-00100-2] [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] [Received: 03/25/2021] [Accepted: 06/22/2021] [Indexed: 12/11/2022] Open
Abstract
The search for Keap1 inhibitors as potential Nrf2 activator is a way of increasing the antioxidant status of the human cellular environ. In this research, we used in silico methods to investigate Keap1-kelch inhibitory potential of Momordica charantia's bioactive compounds in order to predict their Nrf2 activating potential. ADMET profiling, physicochemical properties, molecular docking, molecular dynamics, and Molecular Mechanics-Poisson Boltzmann Surface Area (g_MMPBSA) free energy calculation studies were executed to drive home our aim. Out of all the bioactive compounds of Momordica charantia, catechin (CAT) and chlorogenic acid (CGA) were selected based on their ADMET profile, physicochemical properties, and molecular docking analysis. Molecular docking studies of CAT and CGA to Keap1 kelch domain showed that they have - 9.2 kJ/mol and - 9.1 kJ/mol binding energies respectively with CAT having four hydrogen bond interactions with Keap1 while CGA had three. Analysis after the 30 ns molecular dynamics simulation revealed that CAT and CGA were both stable, although with minimal conformational alterations at the kelch pocket of Keap1. Finally, MMPBSA calculation of the Gibbs free energy of each amino acid interaction with CAT and CGA revealed that CAT had a higher total binding energy than CGA. Therefore, the Keap1 inhibitory capacities and the molecular dynamic characters of CAT and CGA at the Kelch domain of Keap1 suggest a putative Nrf2 signaling activating prowess. Supplementary Information The online version contains supplementary material available at 10.1007/s40203-021-00100-2.
Collapse
|
5
|
Davies MR. Cardiac Safety Pharmacology Modeling. SYSTEMS MEDICINE 2021. [DOI: 10.1016/b978-0-12-801238-3.11545-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022] Open
|
6
|
Llopis-Lorente J, Gomis-Tena J, Cano J, Romero L, Saiz J, Trenor B. In Silico Classifiers for the Assessment of Drug Proarrhythmicity. J Chem Inf Model 2020; 60:5172-5187. [PMID: 32786710 DOI: 10.1021/acs.jcim.0c00201] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Drug-induced torsade de pointes (TdP) is a life-threatening ventricular arrhythmia responsible for the withdrawal of many drugs from the market. Although currently used TdP risk-assessment methods are effective, they are expensive and prone to produce false positives. In recent years, in silico cardiac simulations have proven to be a valuable tool for the prediction of drug effects. The objective of this work is to evaluate different biomarkers of drug-induced proarrhythmic risk and to develop an in silico risk classifier. Cellular simulations were performed using a modified version of the O'Hara et al. ventricular action potential model and existing pharmacological data (IC50 and effective free therapeutic plasma concentration, EFTPC) for 109 drugs of known torsadogenic risk (51 positive). For each compound, four biomarkers were tested: Tx (drug concentration leading to a 10% prolongation of the action potential over the EFTPC), TqNet (net charge carried by ionic currents when exposed to 10 times the EFTPC with respect to the net charge in control), Ttriang (triangulation for a drug concentration of 10 times the EFTPC over triangulation in control), and TEAD (drug concentration originating early afterdepolarizations over EFTPC). Receiver operating characteristic (ROC) curves were built for each biomarker to evaluate their individual predictive quality. At the optimal cutoff point, accuracies for Tx, TqNet, Ttriang, and TEAD were 89.9, 91.7, 90.8, and 78.9% respectively. The resulting accuracy of the hERG IC50 test (current biomarker) was 78.9%. When combining Tx, TqNet and Ttriang into a classifier based on decision trees, the prediction improves, achieving an accuracy of 94.5%. The sensitivity analysis revealed that most of the effects on the action potential are mainly due to changes in IKr, ICaL, INaL and IKs. In fact, considering that drugs affect only these four currents, TdP risk classification can be as accurate as when considering effects on the seven main currents proposed by the CiPA initiative. Finally, we built a ready-to-use tool (based on more than 450 000 simulations), which can be used to quickly assess the proarrhythmic risk of a compound. In conclusion, our in silico tool can be useful for the preclinical assessment of TdP-risk and to reduce costs related with new drug development. The TdP risk-assessment tool and the software used in this work are available at https://riunet.upv.es/handle/10251/136919.
Collapse
Affiliation(s)
- Jordi Llopis-Lorente
- Centro de Investigación e Innovación en Bioingeniería (Ci2B), Universitat Politècnica de València, Camino de Vera s/n, 46022 Valencia, Spain
| | - Julio Gomis-Tena
- Centro de Investigación e Innovación en Bioingeniería (Ci2B), Universitat Politècnica de València, Camino de Vera s/n, 46022 Valencia, Spain
| | - Jordi Cano
- Centro de Investigación e Innovación en Bioingeniería (Ci2B), Universitat Politècnica de València, Camino de Vera s/n, 46022 Valencia, Spain
| | - Lucía Romero
- Centro de Investigación e Innovación en Bioingeniería (Ci2B), Universitat Politècnica de València, Camino de Vera s/n, 46022 Valencia, Spain
| | - Javier Saiz
- Centro de Investigación e Innovación en Bioingeniería (Ci2B), Universitat Politècnica de València, Camino de Vera s/n, 46022 Valencia, Spain
| | - Beatriz Trenor
- Centro de Investigación e Innovación en Bioingeniería (Ci2B), Universitat Politècnica de València, Camino de Vera s/n, 46022 Valencia, Spain
| |
Collapse
|
7
|
Bourdi M, Rudloff U, Patnaik S, Marugan J, Terse PS. Safety assessment of metarrestin in dogs: A clinical candidate targeting a subnuclear structure unique to metastatic cancer cells. Regul Toxicol Pharmacol 2020; 116:104716. [PMID: 32619635 PMCID: PMC8378239 DOI: 10.1016/j.yrtph.2020.104716] [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: 02/14/2020] [Revised: 05/09/2020] [Accepted: 06/16/2020] [Indexed: 11/28/2022]
Abstract
Pancreatic cancer is a leading cause of cancer-related deaths in the U.S. Ninety percent of patients with stage IV pancreatic cancer die within one year of diagnosis due to complications of metastasis. A metastatic potential of cancer cells has been shown to be closely associated with formation of perinucleolar compartment (PNC). Metarrestin, a first-in-class PNC inhibitor, was evaluated for its toxicity, toxicokinetics, and safety pharmacology in beagle dogs following every other day oral (capsule) administration for 28 days to support its introduction into clinical trials. The study consisted of four dose groups: vehicle; 0.25, 0.75 and 1.50 mg/kg/dose. Metarrestin reached its maximum concentration in blood at 3 h (overall median Tmax) across all doses with a mean t1/2 over 168 h of 55.5 h. Dose dependent increase in systemic exposure (Cmax and AUClast) with no sex difference was observed on days 1 and 27. Metarrestin accumulated from Day 1 to Day 27 at all dose levels and in both sexes by an overall factor of about 2.34. No mortality occurred during the dosing period; however, treatment-related clinical signs of toxicity consisting of hypoactivity, shaking/shivering, thinness, irritability, salivation, abnormal gait, tremors, ataxia and intermittent seizure-like activity were seen in both sexes at mid and high dose groups. Treatment-related effects on body weight and food consumption were seen at the mid and high dose levels. Safety pharmacology study showed no treatment-related effects on blood pressure, heart rate, corrected QT, PR, RR, or QRS intervals, or respiratory function parameters (respiratory rate, tidal volume, minute volume). There were no histopathological changes observed, with the exception of transient thymic atrophy which was considered to be non-adverse. Based primarily on clinical signs of toxicity, the No Observed Adverse Effect Level (NOAEL) in dogs was considered to be 0.25 mg/kg metarrestin after every other day dosing for 28 days with a mean of male and female Cmax = 82.5 ng/mL and AUClast = 2521 h*ng/mL, on Day 27.
Collapse
Affiliation(s)
- Mohammed Bourdi
- National Center for Advancing Translational Sciences, NIH, Rockville, Maryland, USA
| | - Udo Rudloff
- Rare Tumor Initiative, Pediatric Oncology Branch, National Cancer Institute, NIH, Bethesda, Maryland, USA
| | - Samarjit Patnaik
- National Center for Advancing Translational Sciences, NIH, Rockville, Maryland, USA
| | - Juan Marugan
- National Center for Advancing Translational Sciences, NIH, Rockville, Maryland, USA
| | - Pramod S Terse
- National Center for Advancing Translational Sciences, NIH, Rockville, Maryland, USA.
| |
Collapse
|
8
|
Hwang M, Lim CH, Leem CH, Shim EB. In silico models for evaluating proarrhythmic risk of drugs. APL Bioeng 2020; 4:021502. [PMID: 32548538 PMCID: PMC7274812 DOI: 10.1063/1.5132618] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2019] [Accepted: 04/27/2020] [Indexed: 02/07/2023] Open
Abstract
Safety evaluation of drugs requires examination of the risk of generating Torsade de Pointes (TdP) because it can lead to sudden cardiac death. Until recently, the QT interval in the electrocardiogram (ECG) has been used in the evaluation of TdP risk because the QT interval is known to be associated with the development of TdP. Although TdP risk evaluation based on QT interval has been successful in removing drugs with TdP risk from the market, some safe drugs may have also been affected due to the low specificity of QT interval-based evaluation. For more accurate evaluation of drug safety, the comprehensive in vitro proarrhythmia assay (CiPA) has been proposed by regulatory agencies, industry, and academia. Although the CiPA initiative includes in silico evaluation of cellular action potential as a component, attempts to utilize in silico simulation in drug safety evaluation are expanding, even to simulating human ECG using biophysical three-dimensional models of the heart and torso under the effects of drugs. Here, we review recent developments in the use of in silico models for the evaluation of the proarrhythmic risk of drugs. We review the single cell, one-dimensional, two-dimensional, and three-dimensional models and their applications reported in the literature and discuss the possibility of utilizing ECG simulation in drug safety evaluation.
Collapse
Affiliation(s)
- Minki Hwang
- SiliconSapiens Inc., Seoul 06097, South Korea
| | - Chul-Hyun Lim
- Department of Mechanical and Biomedical Engineering, Kangwon National University, Chuncheon 24341, South Korea
| | - Chae Hun Leem
- Department of Physiology, College of Medicine, University of Ulsan, Asan Medical Center, Seoul 05505, South Korea
| | | |
Collapse
|
9
|
Kramer J, Himmel HM, Lindqvist A, Stoelzle-Feix S, Chaudhary KW, Li D, Bohme GA, Bridgland-Taylor M, Hebeisen S, Fan J, Renganathan M, Imredy J, Humphries ESA, Brinkwirth N, Strassmaier T, Ohtsuki A, Danker T, Vanoye C, Polonchuk L, Fermini B, Pierson JB, Gintant G. Cross-site and cross-platform variability of automated patch clamp assessments of drug effects on human cardiac currents in recombinant cells. Sci Rep 2020; 10:5627. [PMID: 32221320 PMCID: PMC7101356 DOI: 10.1038/s41598-020-62344-w] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2019] [Accepted: 03/09/2020] [Indexed: 01/01/2023] Open
Abstract
Automated patch clamp (APC) instruments enable efficient evaluation of electrophysiologic effects of drugs on human cardiac currents in heterologous expression systems. Differences in experimental protocols, instruments, and dissimilar site procedures affect the variability of IC50 values characterizing drug block potency. This impacts the utility of APC platforms for assessing a drug's cardiac safety margin. We determined variability of APC data from multiple sites that measured blocking potency of 12 blinded drugs (with different levels of proarrhythmic risk) against four human cardiac currents (hERG [IKr], hCav1.2 [L-Type ICa], peak hNav1.5, [Peak INa], late hNav1.5 [Late INa]) with recommended protocols (to minimize variance) using five APC platforms across 17 sites. IC50 variability (25/75 percentiles) differed for drugs and currents (e.g., 10.4-fold for dofetilide block of hERG current and 4-fold for mexiletine block of hNav1.5 current). Within-platform variance predominated for 4 of 12 hERG blocking drugs and 4 of 6 hNav1.5 blocking drugs. hERG and hNav1.5 block. Bland-Altman plots depicted varying agreement across APC platforms. A follow-up survey suggested multiple sources of experimental variability that could be further minimized by stricter adherence to standard protocols. Adoption of best practices would ensure less variable APC datasets and improved safety margins and proarrhythmic risk assessments.
Collapse
Affiliation(s)
| | | | | | | | | | - Dingzhou Li
- Drug Safety Research & Development, Pfizer, Groton, CT, USA
| | - Georg Andrees Bohme
- Integrated Drug Discovery, High Content Biology Unit, Sanofi R&D, Vitry-Sur-Seine, France
| | | | | | - Jingsong Fan
- Discovery Toxicology, Bristol-Myers Squibb Company, Princeton, NJ, USA
| | | | | | | | | | | | | | - Timm Danker
- Natural and Medical Science Institute at the University of Tübingen, Reutlingen, Germany
| | - Carlos Vanoye
- Northwestern Feinberg School of Medicine, Chicago, IL, USA
| | - Liudmila Polonchuk
- Roche Pharma Research & Early Development, Roche Innovation Center Basel, F. Hoffmann-La Roche Ltd., Basel, Switzerland
| | | | | | | |
Collapse
|
10
|
Parikh J, Di Achille P, Kozloski J, Gurev V. Global Sensitivity Analysis of Ventricular Myocyte Model-Derived Metrics for Proarrhythmic Risk Assessment. Front Pharmacol 2019; 10:1054. [PMID: 31680938 PMCID: PMC6797832 DOI: 10.3389/fphar.2019.01054] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2019] [Accepted: 08/20/2019] [Indexed: 01/08/2023] Open
Abstract
Multiscale computational models of the heart are being extensively investigated for improved assessment of drug-induced torsades de pointes (TdP) risk, a fatal side effect of many drugs. Model-derived metrics such as action potential duration and net charge carried by ionic currents (qNet) have been proposed as potential candidates for TdP risk stratification after being tested on small datasets. Unlike purely statistical approaches, model-derived metrics are thought to provide mechanism-based classification. In particular, qNet has been recently proposed as a surrogate metric for early afterdepolarizations (EADs), which are known to be cellular triggers of TdP. Analysis of critical model components and of the ion channels that have major impact on model-derived metrics can lead to improvements in the confidence of the prediction. In this paper, we analyze large populations of virtual drugs to systematically examine the influence of different ion channels on model-derived metrics that have been proposed for proarrhythmic risk assessment. We demonstrate via global sensitivity analysis (GSA) that model-derived metrics are most sensitive to different sets of input parameters. Similarly, important differences in sensitivity to specific channel blocks are highlighted when classifying drugs into different risk categories by either qNet or a metric directly based on simulated EADs. In particular, the higher sensitivity of qNet to the block of the late sodium channel might explain why its classification accuracy is better than that of the EAD-based metric, as shown for a small set of known drugs. Our results highlight the need for a better mechanistic interpretation of promising metrics like qNet based on a formal analysis of models. GSA should, therefore, constitute an essential component of the in silico workflow for proarrhythmic risk assessment, as an improved understanding of the structure of model-derived metrics could increase confidence in model-predicted risk.
Collapse
|
11
|
Sahli Costabal F, Yao J, Sher A, Kuhl E. Predicting critical drug concentrations and torsadogenic risk using a multiscale exposure-response simulator. PROGRESS IN BIOPHYSICS AND MOLECULAR BIOLOGY 2019; 144:61-76. [PMID: 30482568 PMCID: PMC6483901 DOI: 10.1016/j.pbiomolbio.2018.10.003] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/01/2018] [Revised: 09/21/2018] [Accepted: 10/11/2018] [Indexed: 12/12/2022]
Abstract
Torsades de pointes is a serious side effect of many drugs that can trigger sudden cardiac death, even in patients with structurally normal hearts. Torsadogenic risk has traditionally been correlated with the blockage of a specific potassium channel and a prolonged recovery period in the electrocardiogram. However, the precise mechanisms by which single channel block translates into heart rhythm disorders remain incompletely understood. Here we establish a multiscale exposure-response simulator that converts block-concentration characteristics from single cell recordings into three-dimensional excitation profiles and electrocardiograms to rapidly assess torsadogenic risk. For the drug dofetilide, we characterize the QT interval and heart rate at different drug concentrations and identify the critical concentration at the onset of torsades de pointes: For dofetilide concentrations of 2x, 3x, and 4x, as multiples of the free plasma concentration Cmax = 2.1 nM, the QT interval increased by +62.0%, +71.2%, and +82.3% compared to baseline, and the heart rate changed by -21.7%, -23.3%, and +88.3%. The last number indicates that, at the critical concentration of 4x, the heart spontaneously developed an episode of a torsades-like arrhythmia. Strikingly, this critical drug concentration is higher than the concentration estimated from early afterdepolarizations in single cells and lower than in one-dimensional cable models. Our results highlight the importance of whole heart modeling and explain, at least in part, why current regulatory paradigms often fail to accurately quantify the pro-arrhythmic potential of a drug. Our exposure-response simulator could provide a more mechanistic assessment of pro-arrhythmic risk and help establish science-based guidelines to reduce rhythm disorders, design safer drugs, and accelerate drug development.
Collapse
Affiliation(s)
| | - Jiang Yao
- Dassault Systèmes Simulia Corporation, Johnston, RI, 02919, United States
| | - Anna Sher
- Internal Medicine Research Unit, Pfizer Inc, Cambridge, MA, 02139, United States
| | - Ellen Kuhl
- Department of Mechanical Engineering, Stanford University, Stanford, CA, 94305, United States.
| |
Collapse
|
12
|
Perissinotti L, Guo J, Kudaibergenova M, Lees-Miller J, Ol'khovich M, Sharapova A, Perlovich GL, Muruve DA, Gerull B, Noskov SY, Duff HJ. The Pore-Lipid Interface: Role of Amino-Acid Determinants of Lipophilic Access by Ivabradine to the hERG1 Pore Domain. Mol Pharmacol 2019; 96:259-271. [PMID: 31182542 DOI: 10.1124/mol.118.115642] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2018] [Accepted: 05/28/2019] [Indexed: 12/14/2022] Open
Abstract
Abnormal cardiac electrical activity is a common side effect caused by unintended block of the promiscuous drug target human ether-à-go-go-related gene (hERG1), the pore-forming domain of the delayed rectifier K+ channel in the heart. hERG1 block leads to a prolongation of the QT interval, a phase of the cardiac cycle that underlies myocyte repolarization detectable on the electrocardiogram. Even newly released drugs such as heart-rate lowering agent ivabradine block the rapid delayed rectifier current IKr, prolong action potential duration, and induce potentially lethal arrhythmia known as torsades de pointes. In this study, we describe a critical drug-binding pocket located at the lateral pore surface facing the cellular membrane. Mutations of the conserved M651 residue alter ivabradine-induced block but not by the common hERG1 blocker dofetilide. As revealed by molecular dynamics simulations, binding of ivabradine to a lipophilic pore access site is coupled to a state-dependent reorientation of aromatic residues F557 and F656 in the S5 and S6 helices. We show that the M651 mutation impedes state-dependent dynamics of F557 and F656 aromatic cassettes at the protein-lipid interface, which has a potential to disrupt drug-induced block of the channel. This fundamentally new mechanism coupling the channel dynamics and small-molecule access from the membrane into the hERG1 intracavitary site provides a simple rationale for the well established state-dependence of drug blockade. SIGNIFICANCE STATEMENT: The drug interference with the function of the cardiac hERG channels represents one of the major sources of drug-induced heart disturbances. We found a novel and a critical drug-binding pocket adjacent to a lipid-facing surface of the hERG1 channel, which furthers our molecular understanding of drug-induced QT syndrome.
Collapse
Affiliation(s)
- Laura Perissinotti
- Centre for Molecular Simulation, Department of Biological Sciences, University of Calgary, Calgary, Alberta, Canada (L.P., M.K., S.Y.N.); Libin Cardiovascular Institute of Alberta (J.G., J.-L.M., H.J.D.) and Snyder Institute for Chronic Diseases (D.A.M.), Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada; Institute of Solution Chemistry, Russian Academy of Sciences, Ivanovo, Russian Federation (M.O., A.S., G.L.P.); Department of Cardiac Sciences and Libin Cardiovascular Institute of Alberta, University of Calgary, Calgary, Alberta, Canada (B.G.); and Comprehensive Heart Failure Center and Department of Internal Medicine I, University Hospital Würzburg, Würzburg, Germany (B.G.)
| | - Jiqing Guo
- Centre for Molecular Simulation, Department of Biological Sciences, University of Calgary, Calgary, Alberta, Canada (L.P., M.K., S.Y.N.); Libin Cardiovascular Institute of Alberta (J.G., J.-L.M., H.J.D.) and Snyder Institute for Chronic Diseases (D.A.M.), Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada; Institute of Solution Chemistry, Russian Academy of Sciences, Ivanovo, Russian Federation (M.O., A.S., G.L.P.); Department of Cardiac Sciences and Libin Cardiovascular Institute of Alberta, University of Calgary, Calgary, Alberta, Canada (B.G.); and Comprehensive Heart Failure Center and Department of Internal Medicine I, University Hospital Würzburg, Würzburg, Germany (B.G.)
| | - Meruyert Kudaibergenova
- Centre for Molecular Simulation, Department of Biological Sciences, University of Calgary, Calgary, Alberta, Canada (L.P., M.K., S.Y.N.); Libin Cardiovascular Institute of Alberta (J.G., J.-L.M., H.J.D.) and Snyder Institute for Chronic Diseases (D.A.M.), Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada; Institute of Solution Chemistry, Russian Academy of Sciences, Ivanovo, Russian Federation (M.O., A.S., G.L.P.); Department of Cardiac Sciences and Libin Cardiovascular Institute of Alberta, University of Calgary, Calgary, Alberta, Canada (B.G.); and Comprehensive Heart Failure Center and Department of Internal Medicine I, University Hospital Würzburg, Würzburg, Germany (B.G.)
| | - James Lees-Miller
- Centre for Molecular Simulation, Department of Biological Sciences, University of Calgary, Calgary, Alberta, Canada (L.P., M.K., S.Y.N.); Libin Cardiovascular Institute of Alberta (J.G., J.-L.M., H.J.D.) and Snyder Institute for Chronic Diseases (D.A.M.), Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada; Institute of Solution Chemistry, Russian Academy of Sciences, Ivanovo, Russian Federation (M.O., A.S., G.L.P.); Department of Cardiac Sciences and Libin Cardiovascular Institute of Alberta, University of Calgary, Calgary, Alberta, Canada (B.G.); and Comprehensive Heart Failure Center and Department of Internal Medicine I, University Hospital Würzburg, Würzburg, Germany (B.G.)
| | - Marina Ol'khovich
- Centre for Molecular Simulation, Department of Biological Sciences, University of Calgary, Calgary, Alberta, Canada (L.P., M.K., S.Y.N.); Libin Cardiovascular Institute of Alberta (J.G., J.-L.M., H.J.D.) and Snyder Institute for Chronic Diseases (D.A.M.), Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada; Institute of Solution Chemistry, Russian Academy of Sciences, Ivanovo, Russian Federation (M.O., A.S., G.L.P.); Department of Cardiac Sciences and Libin Cardiovascular Institute of Alberta, University of Calgary, Calgary, Alberta, Canada (B.G.); and Comprehensive Heart Failure Center and Department of Internal Medicine I, University Hospital Würzburg, Würzburg, Germany (B.G.)
| | - Angelica Sharapova
- Centre for Molecular Simulation, Department of Biological Sciences, University of Calgary, Calgary, Alberta, Canada (L.P., M.K., S.Y.N.); Libin Cardiovascular Institute of Alberta (J.G., J.-L.M., H.J.D.) and Snyder Institute for Chronic Diseases (D.A.M.), Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada; Institute of Solution Chemistry, Russian Academy of Sciences, Ivanovo, Russian Federation (M.O., A.S., G.L.P.); Department of Cardiac Sciences and Libin Cardiovascular Institute of Alberta, University of Calgary, Calgary, Alberta, Canada (B.G.); and Comprehensive Heart Failure Center and Department of Internal Medicine I, University Hospital Würzburg, Würzburg, Germany (B.G.)
| | - German L Perlovich
- Centre for Molecular Simulation, Department of Biological Sciences, University of Calgary, Calgary, Alberta, Canada (L.P., M.K., S.Y.N.); Libin Cardiovascular Institute of Alberta (J.G., J.-L.M., H.J.D.) and Snyder Institute for Chronic Diseases (D.A.M.), Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada; Institute of Solution Chemistry, Russian Academy of Sciences, Ivanovo, Russian Federation (M.O., A.S., G.L.P.); Department of Cardiac Sciences and Libin Cardiovascular Institute of Alberta, University of Calgary, Calgary, Alberta, Canada (B.G.); and Comprehensive Heart Failure Center and Department of Internal Medicine I, University Hospital Würzburg, Würzburg, Germany (B.G.)
| | - Daniel A Muruve
- Centre for Molecular Simulation, Department of Biological Sciences, University of Calgary, Calgary, Alberta, Canada (L.P., M.K., S.Y.N.); Libin Cardiovascular Institute of Alberta (J.G., J.-L.M., H.J.D.) and Snyder Institute for Chronic Diseases (D.A.M.), Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada; Institute of Solution Chemistry, Russian Academy of Sciences, Ivanovo, Russian Federation (M.O., A.S., G.L.P.); Department of Cardiac Sciences and Libin Cardiovascular Institute of Alberta, University of Calgary, Calgary, Alberta, Canada (B.G.); and Comprehensive Heart Failure Center and Department of Internal Medicine I, University Hospital Würzburg, Würzburg, Germany (B.G.)
| | - Brenda Gerull
- Centre for Molecular Simulation, Department of Biological Sciences, University of Calgary, Calgary, Alberta, Canada (L.P., M.K., S.Y.N.); Libin Cardiovascular Institute of Alberta (J.G., J.-L.M., H.J.D.) and Snyder Institute for Chronic Diseases (D.A.M.), Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada; Institute of Solution Chemistry, Russian Academy of Sciences, Ivanovo, Russian Federation (M.O., A.S., G.L.P.); Department of Cardiac Sciences and Libin Cardiovascular Institute of Alberta, University of Calgary, Calgary, Alberta, Canada (B.G.); and Comprehensive Heart Failure Center and Department of Internal Medicine I, University Hospital Würzburg, Würzburg, Germany (B.G.)
| | - Sergei Yu Noskov
- Centre for Molecular Simulation, Department of Biological Sciences, University of Calgary, Calgary, Alberta, Canada (L.P., M.K., S.Y.N.); Libin Cardiovascular Institute of Alberta (J.G., J.-L.M., H.J.D.) and Snyder Institute for Chronic Diseases (D.A.M.), Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada; Institute of Solution Chemistry, Russian Academy of Sciences, Ivanovo, Russian Federation (M.O., A.S., G.L.P.); Department of Cardiac Sciences and Libin Cardiovascular Institute of Alberta, University of Calgary, Calgary, Alberta, Canada (B.G.); and Comprehensive Heart Failure Center and Department of Internal Medicine I, University Hospital Würzburg, Würzburg, Germany (B.G.)
| | - Henry J Duff
- Centre for Molecular Simulation, Department of Biological Sciences, University of Calgary, Calgary, Alberta, Canada (L.P., M.K., S.Y.N.); Libin Cardiovascular Institute of Alberta (J.G., J.-L.M., H.J.D.) and Snyder Institute for Chronic Diseases (D.A.M.), Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada; Institute of Solution Chemistry, Russian Academy of Sciences, Ivanovo, Russian Federation (M.O., A.S., G.L.P.); Department of Cardiac Sciences and Libin Cardiovascular Institute of Alberta, University of Calgary, Calgary, Alberta, Canada (B.G.); and Comprehensive Heart Failure Center and Department of Internal Medicine I, University Hospital Würzburg, Würzburg, Germany (B.G.)
| |
Collapse
|
13
|
Li Z, Garnett C, Strauss DG. Quantitative Systems Pharmacology Models for a New International Cardiac Safety Regulatory Paradigm: An Overview of the Comprehensive In Vitro Proarrhythmia Assay In Silico Modeling Approach. CPT Pharmacometrics Syst Pharmacol 2019; 8:371-379. [PMID: 31044559 PMCID: PMC6617836 DOI: 10.1002/psp4.12423] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2019] [Accepted: 04/15/2019] [Indexed: 12/17/2022] Open
Abstract
As a relatively new discipline, quantitative systems pharmacology has seen a significant increase in the application and utility of drug development. One area that could greatly benefit from such an approach is in the proarrhythmia assessment of new drugs. The Comprehensive In Vitro Proarrhythmia Assay (CiPA) Initiative is a global public-private partnership project that has developed an integrated approach using mechanistic in silico models for proarrhythmia risk prediction. Progress to date has led to the formation of the International Council on Harmonisation Implementation Working Group to revise regulatory guidelines via the Questions-and-Answers process to address the best practices for proarrhythmia models and how they can impact clinical drug development. This article reviews the CiPA in silico model-development process, focusing on its unique development and validation strategy, and summarizes the lessons learned as consideration points for the ongoing implementation of CiPA-like in silico models in drug development.
Collapse
Affiliation(s)
- Zhihua Li
- Division of Applied Regulatory ScienceOffice of Clinical PharmacologyOffice of Translational SciencesCenter for Drug Evaluation and ResearchUS Food and Drug AdministrationSilver SpringMarylandUSA
| | - Christine Garnett
- Division of Cardiovascular and Renal ProductsOffice of Drug Evaluation IOffice of New DrugsCenter for Drug Evaluation and ResearchUS Food and Drug AdministrationSilver SpringMarylandUSA
| | - David G. Strauss
- Division of Applied Regulatory ScienceOffice of Clinical PharmacologyOffice of Translational SciencesCenter for Drug Evaluation and ResearchUS Food and Drug AdministrationSilver SpringMarylandUSA
| |
Collapse
|
14
|
Lesuisse D, Malanda A, Peyronel JF, Evanno Y, Lardenois P, De-Peretti D, Abécassis PY, Barnéoud P, Brunel P, Burgevin MC, Cegarra C, Auger F, Dommergue A, Lafon C, Even L, Tsi J, Luc TPH, Almario A, Olivier A, Castel MN, Taupin V, Rooney T, Vigé X. Development of a novel NURR1/NOT agonist from hit to lead and candidate for the potential treatment of Parkinson's disease. Bioorg Med Chem Lett 2019; 29:929-932. [DOI: 10.1016/j.bmcl.2019.01.024] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2018] [Revised: 01/12/2019] [Accepted: 01/17/2019] [Indexed: 12/11/2022]
|
15
|
Goversen B, Jonsson MK, van den Heuvel NH, Rijken R, Vos MA, van Veen TA, de Boer TP. The influence of hERG1a and hERG1b isoforms on drug safety screening in iPSC-CMs. PROGRESS IN BIOPHYSICS AND MOLECULAR BIOLOGY 2019; 149:86-98. [PMID: 30826123 DOI: 10.1016/j.pbiomolbio.2019.02.003] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/15/2018] [Revised: 01/14/2019] [Accepted: 02/08/2019] [Indexed: 01/03/2023]
Abstract
The human Ether-à-go-go Related Gene (hERG) encodes the pore forming subunit of the channel that conducts the rapid delayed rectifier potassium current IKr. IKr drives repolarization in the heart and when IKr is dysfunctional, cardiac repolarization delays, the QT interval on the electrocardiogram (ECG) prolongs and the risk of developing lethal arrhythmias such as Torsade de Pointes (TdP) increases. TdP risk is incorporated in drug safety screening for cardiotoxicity where hERG is the main target since the IKr channels appear highly sensitive to blockage. hERG block is also included as an important read-out in the Comprehensive in Vitro Proarrhythmia Assay (CiPA) initiative which aims to combine in vitro and in silico experiments on induced pluripotent stem cell-derived cardiomyocytes (iPSC-CMs) to screen for cardiotoxicity. However, the hERG channel has some unique features to consider for drug safety screening, which we will discuss in this study. The hERG channel consists of different isoforms, hERG1a and hERG1b, which individually influence the kinetics of the channel and the drug response in the human heart and in iPSC-CMs. hERG1b is often underappreciated in iPSC-CM studies, drug screening assays and in silico models, and the fact that its contribution might substantially differ between iPSC-CM and healthy but also diseased human heart, adds to this problem. In this study we show that the activation kinetics in iPSC-CMs resemble hERG1b kinetics using Cs+ as a charge carrier. Not including hERG1b in drug safety testing might underestimate the actual role of hERG1b in repolarization and drug response, and might lead to inappropriate conclusions. We stress to focus more on including hERG1b in drug safety testing concerning IKr.
Collapse
Affiliation(s)
- Birgit Goversen
- Department of Medical Physiology, Division Heart & Lungs, University Medical Center Utrecht, the Netherlands
| | - Malin Kb Jonsson
- Department of Medical Physiology, Division Heart & Lungs, University Medical Center Utrecht, the Netherlands; Bioscience Heart Failure, Cardiovascular, Renal and Metabolic Diseases, IMED Biotech Unit, AstraZeneca, Gothenburg, Sweden
| | - Nikki Hl van den Heuvel
- Department of Medical Physiology, Division Heart & Lungs, University Medical Center Utrecht, the Netherlands
| | - Rianne Rijken
- Department of Medical Physiology, Division Heart & Lungs, University Medical Center Utrecht, the Netherlands
| | - Marc A Vos
- Department of Medical Physiology, Division Heart & Lungs, University Medical Center Utrecht, the Netherlands
| | - Toon Ab van Veen
- Department of Medical Physiology, Division Heart & Lungs, University Medical Center Utrecht, the Netherlands
| | - Teun P de Boer
- Department of Medical Physiology, Division Heart & Lungs, University Medical Center Utrecht, the Netherlands.
| |
Collapse
|
16
|
Lee W, Windley MJ, Perry MD, Vandenberg JI, Hill AP. Protocol-Dependent Differences in IC 50 Values Measured in Human Ether-Á-Go-Go-Related Gene Assays Occur in a Predictable Way and Can Be Used to Quantify State Preference of Drug Binding. Mol Pharmacol 2019; 95:537-550. [PMID: 30770456 DOI: 10.1124/mol.118.115220] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2018] [Accepted: 02/10/2019] [Indexed: 12/22/2022] Open
Abstract
Current guidelines around preclinical screening for drug-induced arrhythmias require the measurement of the potency of block of voltage-gated potassium channel subtype 11.1 (Kv11.1) as a surrogate for risk. A shortcoming of this approach is that the measured IC50 of Kv11.1 block varies widely depending on the voltage protocol used in electrophysiological assays. In this study, we aimed to investigate the factors that contribute to these differences and to identify whether it is possible to make predictions about protocol-dependent block that might facilitate the comparison of potencies measured using different assays. Our data demonstrate that state preferential binding, together with drug-binding kinetics and trapping, is an important determinant of the protocol dependence of Kv11.1 block. We show for the first time that differences in IC50 measured between protocols occurs in a predictable way, such that machine-learning algorithms trained using a selection of simple voltage protocols can indeed predict protocol-dependent potency. Furthermore, we also show that the preference of a drug for binding to the open versus the inactivated state of Kv11.1 can also be inferred from differences in IC50 values measured between protocols. Our work therefore identifies how state preferential drug binding is a major determinant of the protocol dependence of IC50 values measured in preclinical Kv11.1 assays. It also provides a novel method for quantifying the state dependence of Kv11.1 drug binding that will facilitate the development of more complete models of drug binding to Kv11.1 and improve our understanding of proarrhythmic risk associated with compounds that block Kv11.1.
Collapse
Affiliation(s)
- William Lee
- Victor Chang Cardiac Research Institute (W.L., M.J.W., M.D.P., J.I.V., A.P.H.) and St Vincent's Clinical School (W.L., M.J.W., M.D.P., J.I.V., A.P.H.), University of New South Wales, Darlinghurst, New South Wales, Australia
| | - Monique J Windley
- Victor Chang Cardiac Research Institute (W.L., M.J.W., M.D.P., J.I.V., A.P.H.) and St Vincent's Clinical School (W.L., M.J.W., M.D.P., J.I.V., A.P.H.), University of New South Wales, Darlinghurst, New South Wales, Australia
| | - Matthew D Perry
- Victor Chang Cardiac Research Institute (W.L., M.J.W., M.D.P., J.I.V., A.P.H.) and St Vincent's Clinical School (W.L., M.J.W., M.D.P., J.I.V., A.P.H.), University of New South Wales, Darlinghurst, New South Wales, Australia
| | - Jamie I Vandenberg
- Victor Chang Cardiac Research Institute (W.L., M.J.W., M.D.P., J.I.V., A.P.H.) and St Vincent's Clinical School (W.L., M.J.W., M.D.P., J.I.V., A.P.H.), University of New South Wales, Darlinghurst, New South Wales, Australia
| | - Adam P Hill
- Victor Chang Cardiac Research Institute (W.L., M.J.W., M.D.P., J.I.V., A.P.H.) and St Vincent's Clinical School (W.L., M.J.W., M.D.P., J.I.V., A.P.H.), University of New South Wales, Darlinghurst, New South Wales, Australia
| |
Collapse
|
17
|
Windley MJ, Lee W, Vandenberg JI, Hill AP. The Temperature Dependence of Kinetics Associated with Drug Block of hERG Channels Is Compound-Specific and an Important Factor for Proarrhythmic Risk Prediction. Mol Pharmacol 2018; 94:760-769. [DOI: 10.1124/mol.117.111534] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2017] [Accepted: 05/02/2018] [Indexed: 01/08/2023] Open
|
18
|
Mistry HB. Complex versus simple models: ion-channel cardiac toxicity prediction. PeerJ 2018; 6:e4352. [PMID: 29423349 PMCID: PMC5804316 DOI: 10.7717/peerj.4352] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2017] [Accepted: 01/19/2018] [Indexed: 01/08/2023] Open
Abstract
There is growing interest in applying detailed mathematical models of the heart for ion-channel related cardiac toxicity prediction. However, a debate as to whether such complex models are required exists. Here an assessment in the predictive performance between two established large-scale biophysical cardiac models and a simple linear model Bnet was conducted. Three ion-channel data-sets were extracted from literature. Each compound was designated a cardiac risk category using two different classification schemes based on information within CredibleMeds. The predictive performance of each model within each data-set for each classification scheme was assessed via a leave-one-out cross validation. Overall the Bnet model performed equally as well as the leading cardiac models in two of the data-sets and outperformed both cardiac models on the latest. These results highlight the importance of benchmarking complex versus simple models but also encourage the development of simple models.
Collapse
Affiliation(s)
- Hitesh B. Mistry
- Division of Pharmacy, University of Manchester, Manchester, United Kingdom
| |
Collapse
|
19
|
Krogh-Madsen T, Jacobson AF, Ortega FA, Christini DJ. Global Optimization of Ventricular Myocyte Model to Multi-Variable Objective Improves Predictions of Drug-Induced Torsades de Pointes. Front Physiol 2017; 8:1059. [PMID: 29311985 PMCID: PMC5742183 DOI: 10.3389/fphys.2017.01059] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2017] [Accepted: 12/04/2017] [Indexed: 01/22/2023] Open
Abstract
In silico cardiac myocyte models present powerful tools for drug safety testing and for predicting phenotypical consequences of ion channel mutations, but their accuracy is sometimes limited. For example, several models describing human ventricular electrophysiology perform poorly when simulating effects of long QT mutations. Model optimization represents one way of obtaining models with stronger predictive power. Using a recent human ventricular myocyte model, we demonstrate that model optimization to clinical long QT data, in conjunction with physiologically-based bounds on intracellular calcium and sodium concentrations, better constrains model parameters. To determine if the model optimized to congenital long QT data better predicts risk of drug-induced long QT arrhythmogenesis, in particular Torsades de Pointes risk, we tested the optimized model against a database of known arrhythmogenic and non-arrhythmogenic ion channel blockers. When doing so, the optimized model provided an improved risk assessment. In particular, we demonstrate an elimination of false-positive outcomes generated by the baseline model, in which simulations of non-torsadogenic drugs, in particular verapamil, predict action potential prolongation. Our results underscore the importance of currents beyond those directly impacted by a drug block in determining torsadogenic risk. Our study also highlights the need for rich data in cardiac myocyte model optimization and substantiates such optimization as a method to generate models with higher accuracy of predictions of drug-induced cardiotoxicity.
Collapse
Affiliation(s)
- Trine Krogh-Madsen
- Greenberg Division of Cardiology, Department of Medicine, Weill Cornell Medicine, New York, NY, United States.,Institute for Computational Biomedicine, Weill Cornell Medicine, New York, NY, United States.,Cardiovascular Research Institute, Weill Cornell Medicine, New York, NY, United States
| | - Anna F Jacobson
- Cardiovascular Research Institute, Weill Cornell Medicine, New York, NY, United States
| | - Francis A Ortega
- Physiology, Biophysics and Systems Biology Graduate Program, Weill Cornell Graduate School, New York, NY, United States
| | - David J Christini
- Greenberg Division of Cardiology, Department of Medicine, Weill Cornell Medicine, New York, NY, United States.,Institute for Computational Biomedicine, Weill Cornell Medicine, New York, NY, United States.,Cardiovascular Research Institute, Weill Cornell Medicine, New York, NY, United States
| |
Collapse
|
20
|
Lee W, Windley MJ, Vandenberg JI, Hill AP. In Vitro and In Silico Risk Assessment in Acquired Long QT Syndrome: The Devil Is in the Details. Front Physiol 2017; 8:934. [PMID: 29201009 PMCID: PMC5696636 DOI: 10.3389/fphys.2017.00934] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2017] [Accepted: 11/03/2017] [Indexed: 12/16/2022] Open
Abstract
Acquired long QT syndrome, mostly as a result of drug block of the Kv11. 1 potassium channel in the heart, is characterized by delayed cardiac myocyte repolarization, prolongation of the T interval on the ECG, syncope and sudden cardiac death due to the polymorphic ventricular arrhythmia Torsade de Pointes (TdP). In recent years, efforts are underway through the Comprehensive in vitro proarrhythmic assay (CiPA) initiative, to develop better tests for this drug induced arrhythmia based in part on in silico simulations of pharmacological disruption of repolarization. However, drug binding to Kv11.1 is more complex than a simple binary molecular reaction, meaning simple steady state measures of potency are poor surrogates for risk. As a result, there is a plethora of mechanistic detail describing the drug/Kv11.1 interaction—such as drug binding kinetics, state preference, temperature dependence and trapping—that needs to be considered when developing in silico models for risk prediction. In addition to this, other factors, such as multichannel pharmacological profile and the nature of the ventricular cell models used in simulations also need to be considered in the search for the optimum in silico approach. Here we consider how much of mechanistic detail needs to be included for in silico models to accurately predict risk and further, how much of this detail can be retrieved from protocols that are practical to implement in high throughout screens as part of next generation of preclinical in silico drug screening approaches?
Collapse
Affiliation(s)
- William Lee
- Molecular Cardiology and Biophysics Division, Victor Chang Cardiac Research Institute, Darlinghurst, NSW, Australia.,St. Vincent's Clinical School, University of New South Wales, Sydney, NSW, Australia
| | - Monique J Windley
- Molecular Cardiology and Biophysics Division, Victor Chang Cardiac Research Institute, Darlinghurst, NSW, Australia.,St. Vincent's Clinical School, University of New South Wales, Sydney, NSW, Australia
| | - Jamie I Vandenberg
- Molecular Cardiology and Biophysics Division, Victor Chang Cardiac Research Institute, Darlinghurst, NSW, Australia.,St. Vincent's Clinical School, University of New South Wales, Sydney, NSW, Australia
| | - Adam P Hill
- Molecular Cardiology and Biophysics Division, Victor Chang Cardiac Research Institute, Darlinghurst, NSW, Australia.,St. Vincent's Clinical School, University of New South Wales, Sydney, NSW, Australia
| |
Collapse
|
21
|
Characterization of loperamide-mediated block of hERG channels at physiological temperature and its proarrhythmia propensity. J Pharmacol Toxicol Methods 2017; 88:109-122. [DOI: 10.1016/j.vascn.2017.08.006] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2017] [Revised: 08/14/2017] [Accepted: 08/18/2017] [Indexed: 02/05/2023]
|
22
|
Dutta S, Chang KC, Beattie KA, Sheng J, Tran PN, Wu WW, Wu M, Strauss DG, Colatsky T, Li Z. Optimization of an In silico Cardiac Cell Model for Proarrhythmia Risk Assessment. Front Physiol 2017; 8:616. [PMID: 28878692 PMCID: PMC5572155 DOI: 10.3389/fphys.2017.00616] [Citation(s) in RCA: 112] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2017] [Accepted: 08/09/2017] [Indexed: 12/19/2022] Open
Abstract
Drug-induced Torsade-de-Pointes (TdP) has been responsible for the withdrawal of many drugs from the market and is therefore of major concern to global regulatory agencies and the pharmaceutical industry. The Comprehensive in vitro Proarrhythmia Assay (CiPA) was proposed to improve prediction of TdP risk, using in silico models and in vitro multi-channel pharmacology data as integral parts of this initiative. Previously, we reported that combining dynamic interactions between drugs and the rapid delayed rectifier potassium current (IKr) with multi-channel pharmacology is important for TdP risk classification, and we modified the original O'Hara Rudy ventricular cell mathematical model to include a Markov model of IKr to represent dynamic drug-IKr interactions (IKr-dynamic ORd model). We also developed a novel metric that could separate drugs with different TdP liabilities at high concentrations based on total electronic charge carried by the major inward ionic currents during the action potential. In this study, we further optimized the IKr-dynamic ORd model by refining model parameters using published human cardiomyocyte experimental data under control and drug block conditions. Using this optimized model and manual patch clamp data, we developed an updated version of the metric that quantifies the net electronic charge carried by major inward and outward ionic currents during the steady state action potential, which could classify the level of drug-induced TdP risk across a wide range of concentrations and pacing rates. We also established a framework to quantitatively evaluate a system's robustness against the induction of early afterdepolarizations (EADs), and demonstrated that the new metric is correlated with the cell's robustness to the pro-EAD perturbation of IKr conductance reduction. In summary, in this work we present an optimized model that is more consistent with experimental data, an improved metric that can classify drugs at concentrations both near and higher than clinical exposure, and a physiological framework to check the relationship between a metric and EAD. These findings provide a solid foundation for using in silico models for the regulatory assessment of TdP risk under the CiPA paradigm.
Collapse
Affiliation(s)
- Sara Dutta
- Division of Applied Regulatory Science, Office of Clinical Pharmacology, Office of Translational Sciences, Center for Drug Evaluation and Research, U.S. Food and Drug AdministrationSilver Spring, MD, United States
| | - Kelly C Chang
- Division of Applied Regulatory Science, Office of Clinical Pharmacology, Office of Translational Sciences, Center for Drug Evaluation and Research, U.S. Food and Drug AdministrationSilver Spring, MD, United States
| | - Kylie A Beattie
- Division of Applied Regulatory Science, Office of Clinical Pharmacology, Office of Translational Sciences, Center for Drug Evaluation and Research, U.S. Food and Drug AdministrationSilver Spring, MD, United States
| | - Jiansong Sheng
- Division of Applied Regulatory Science, Office of Clinical Pharmacology, Office of Translational Sciences, Center for Drug Evaluation and Research, U.S. Food and Drug AdministrationSilver Spring, MD, United States
| | - Phu N Tran
- Division of Applied Regulatory Science, Office of Clinical Pharmacology, Office of Translational Sciences, Center for Drug Evaluation and Research, U.S. Food and Drug AdministrationSilver Spring, MD, United States
| | - Wendy W Wu
- Division of Applied Regulatory Science, Office of Clinical Pharmacology, Office of Translational Sciences, Center for Drug Evaluation and Research, U.S. Food and Drug AdministrationSilver Spring, MD, United States
| | - Min Wu
- Division of Applied Regulatory Science, Office of Clinical Pharmacology, Office of Translational Sciences, Center for Drug Evaluation and Research, U.S. Food and Drug AdministrationSilver Spring, MD, United States
| | - David G Strauss
- Division of Applied Regulatory Science, Office of Clinical Pharmacology, Office of Translational Sciences, Center for Drug Evaluation and Research, U.S. Food and Drug AdministrationSilver Spring, MD, United States
| | - Thomas Colatsky
- Division of Applied Regulatory Science, Office of Clinical Pharmacology, Office of Translational Sciences, Center for Drug Evaluation and Research, U.S. Food and Drug AdministrationSilver Spring, MD, United States
| | - Zhihua Li
- Division of Applied Regulatory Science, Office of Clinical Pharmacology, Office of Translational Sciences, Center for Drug Evaluation and Research, U.S. Food and Drug AdministrationSilver Spring, MD, United States
| |
Collapse
|
23
|
Britton OJ, Abi-Gerges N, Page G, Ghetti A, Miller PE, Rodriguez B. Quantitative Comparison of Effects of Dofetilide, Sotalol, Quinidine, and Verapamil between Human Ex vivo Trabeculae and In silico Ventricular Models Incorporating Inter-Individual Action Potential Variability. Front Physiol 2017; 8:597. [PMID: 28868038 PMCID: PMC5563361 DOI: 10.3389/fphys.2017.00597] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2017] [Accepted: 08/02/2017] [Indexed: 01/20/2023] Open
Abstract
Background:In silico modeling could soon become a mainstream method of pro-arrhythmic risk assessment in drug development. However, a lack of human-specific data and appropriate modeling techniques has previously prevented quantitative comparison of drug effects between in silico models and recordings from human cardiac preparations. Here, we directly compare changes in repolarization biomarkers caused by dofetilide, dl-sotalol, quinidine, and verapamil, between in silico populations of human ventricular cell models and ex vivo human ventricular trabeculae. Methods and Results:Ex vivo recordings from human ventricular trabeculae in control conditions were used to develop populations of in silico human ventricular cell models that integrated intra- and inter-individual variability in action potential (AP) biomarker values. Models were based on the O'Hara-Rudy ventricular cardiomyocyte model, but integrated experimental AP variability through variation in underlying ionic conductances. Changes to AP duration, triangulation and early after-depolarization occurrence from application of the four drugs at multiple concentrations and pacing frequencies were compared between simulations and experiments. To assess the impact of variability in IC50 measurements, and the effects of including state-dependent drug binding dynamics, each drug simulation was repeated with two different IC50 datasets, and with both the original O'Hara-Rudy hERG model and a recently published state-dependent model of hERG and hERG block. For the selective hERG blockers dofetilide and sotalol, simulation predictions of AP prolongation and repolarization abnormality occurrence showed overall good agreement with experiments. However, for multichannel blockers quinidine and verapamil, simulations were not in agreement with experiments across all IC50 datasets and IKr block models tested. Quinidine simulations resulted in overprolonged APs and high incidence of repolarization abnormalities, which were not observed in experiments. Verapamil simulations showed substantial AP prolongation while experiments showed mild AP shortening. Conclusions: Results for dofetilide and sotalol show good agreement between experiments and simulations for selective compounds, however lack of agreement from simulations of quinidine and verapamil suggest further work is needed to understand the more complex electrophysiological effects of these multichannel blocking drugs.
Collapse
Affiliation(s)
- Oliver J. Britton
- Department of Computer Science, University of OxfordOxford, United Kingdom
| | | | - Guy Page
- AnaBios CorporationSan Diego, CA, United States
| | | | | | - Blanca Rodriguez
- Department of Computer Science, University of OxfordOxford, United Kingdom
| |
Collapse
|
24
|
Kratz JM, Grienke U, Scheel O, Mann SA, Rollinger JM. Natural products modulating the hERG channel: heartaches and hope. Nat Prod Rep 2017; 34:957-980. [PMID: 28497823 PMCID: PMC5708533 DOI: 10.1039/c7np00014f] [Citation(s) in RCA: 42] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
This review covers natural products modulating the hERG potassium channel. Risk assessment strategies, structural features of blockers, and the duality target/antitarget are discussed.
Covering: 1996–December 2016 The human Ether-à-go-go Related Gene (hERG) channel is a voltage-gated potassium channel playing an essential role in the normal electrical activity in the heart. It is involved in the repolarization and termination of action potentials in excitable cardiac cells. Mutations in the hERG gene and hERG channel blockage by small molecules are associated with increased risk of fatal arrhythmias. Several drugs have been withdrawn from the market due to hERG channel-related cardiotoxicity. Moreover, as a result of its notorious ligand promiscuity, this ion channel has emerged as an important antitarget in early drug discovery and development. Surprisingly, the hERG channel blocking profile of natural compounds present in frequently consumed botanicals (i.e. dietary supplements, spices, and herbal medicinal products) is not routinely assessed. This comprehensive review will address these issues and provide a critical compilation of hERG channel data for isolated natural products and extracts over the past two decades (1996–2016). In addition, the review will provide (i) a solid basis for the molecular understanding of the physiological functions of the hERG channel, (ii) the translational potential of in vitro/in vivo results to cardiotoxicity in humans, (iii) approaches for the identification of hERG channel blockers from natural sources, (iv) future perspectives for cardiac safety guidelines and their applications within phytopharmaceuticals and dietary supplements, and (v) novel applications of hERG channel modulation (e.g. as a drug target).
Collapse
Affiliation(s)
- Jadel M Kratz
- Department of Pharmacognosy, Faculty of Life Sciences, University of Vienna, Althanstraße 14, 1090 Vienna, Austria.
| | | | | | | | | |
Collapse
|
25
|
Li Z, Dutta S, Sheng J, Tran PN, Wu W, Chang K, Mdluli T, Strauss DG, Colatsky T. Improving the In Silico Assessment of Proarrhythmia Risk by Combining hERG (Human Ether-à-go-go-Related Gene) Channel-Drug Binding Kinetics and Multichannel Pharmacology. Circ Arrhythm Electrophysiol 2017; 10:e004628. [PMID: 28202629 DOI: 10.1161/circep.116.004628] [Citation(s) in RCA: 114] [Impact Index Per Article: 16.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/01/2016] [Accepted: 01/19/2017] [Indexed: 11/16/2022]
Abstract
BACKGROUND The current proarrhythmia safety testing paradigm, although highly efficient in preventing new torsadogenic drugs from entering the market, has important limitations that can restrict the development and use of valuable new therapeutics. The CiPA (Comprehensive in vitro Proarrhythmia Assay) proposes to overcome these limitations by evaluating drug effects on multiple cardiac ion channels in vitro and using these data in a predictive in silico model of the adult human ventricular myocyte. A set of drugs with known clinical torsade de pointes risk was selected to develop and calibrate the in silico model. METHODS AND RESULTS Manual patch-clamp data assessing drug effects on expressed cardiac ion channels were integrated into the O'Hara-Rudy myocyte model modified to include dynamic drug-hERG channel (human Ether-à-go-go-Related Gene) interactions. Together with multichannel pharmacology data, this model predicts that compounds with high torsadogenic risk are more likely to be trapped within the hERG channel and show stronger reverse use dependency of action potential prolongation. Furthermore, drug-induced changes in the amount of electronic charge carried by the late sodium and L-type calcium currents was evaluated as a potential metric for assigning torsadogenic risk. CONCLUSIONS Modeling dynamic drug-hERG channel interactions and multi-ion channel pharmacology improves the prediction of torsadogenic risk. With further development, these methods have the potential to improve the regulatory assessment of drug safety models under the CiPA paradigm.
Collapse
Affiliation(s)
- Zhihua Li
- From the Division of Applied Regulatory Science, Office of Clinical Pharmacology, Office of Translational Sciences, Center for Drug Evaluation and Research, US Food and Drug Administration, Silver Spring, MD.
| | - Sara Dutta
- From the Division of Applied Regulatory Science, Office of Clinical Pharmacology, Office of Translational Sciences, Center for Drug Evaluation and Research, US Food and Drug Administration, Silver Spring, MD
| | - Jiansong Sheng
- From the Division of Applied Regulatory Science, Office of Clinical Pharmacology, Office of Translational Sciences, Center for Drug Evaluation and Research, US Food and Drug Administration, Silver Spring, MD
| | - Phu N Tran
- From the Division of Applied Regulatory Science, Office of Clinical Pharmacology, Office of Translational Sciences, Center for Drug Evaluation and Research, US Food and Drug Administration, Silver Spring, MD
| | - Wendy Wu
- From the Division of Applied Regulatory Science, Office of Clinical Pharmacology, Office of Translational Sciences, Center for Drug Evaluation and Research, US Food and Drug Administration, Silver Spring, MD
| | - Kelly Chang
- From the Division of Applied Regulatory Science, Office of Clinical Pharmacology, Office of Translational Sciences, Center for Drug Evaluation and Research, US Food and Drug Administration, Silver Spring, MD
| | - Thembi Mdluli
- From the Division of Applied Regulatory Science, Office of Clinical Pharmacology, Office of Translational Sciences, Center for Drug Evaluation and Research, US Food and Drug Administration, Silver Spring, MD
| | - David G Strauss
- From the Division of Applied Regulatory Science, Office of Clinical Pharmacology, Office of Translational Sciences, Center for Drug Evaluation and Research, US Food and Drug Administration, Silver Spring, MD
| | - Thomas Colatsky
- From the Division of Applied Regulatory Science, Office of Clinical Pharmacology, Office of Translational Sciences, Center for Drug Evaluation and Research, US Food and Drug Administration, Silver Spring, MD
| |
Collapse
|
26
|
Hartung T, FitzGerald RE, Jennings P, Mirams GR, Peitsch MC, Rostami-Hodjegan A, Shah I, Wilks MF, Sturla SJ. Systems Toxicology: Real World Applications and Opportunities. Chem Res Toxicol 2017; 30:870-882. [PMID: 28362102 PMCID: PMC5396025 DOI: 10.1021/acs.chemrestox.7b00003] [Citation(s) in RCA: 68] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2017] [Indexed: 01/14/2023]
Abstract
Systems Toxicology aims to change the basis of how adverse biological effects of xenobiotics are characterized from empirical end points to describing modes of action as adverse outcome pathways and perturbed networks. Toward this aim, Systems Toxicology entails the integration of in vitro and in vivo toxicity data with computational modeling. This evolving approach depends critically on data reliability and relevance, which in turn depends on the quality of experimental models and bioanalysis techniques used to generate toxicological data. Systems Toxicology involves the use of large-scale data streams ("big data"), such as those derived from omics measurements that require computational means for obtaining informative results. Thus, integrative analysis of multiple molecular measurements, particularly acquired by omics strategies, is a key approach in Systems Toxicology. In recent years, there have been significant advances centered on in vitro test systems and bioanalytical strategies, yet a frontier challenge concerns linking observed network perturbations to phenotypes, which will require understanding pathways and networks that give rise to adverse responses. This summary perspective from a 2016 Systems Toxicology meeting, an international conference held in the Alps of Switzerland, describes the limitations and opportunities of selected emerging applications in this rapidly advancing field. Systems Toxicology aims to change the basis of how adverse biological effects of xenobiotics are characterized, from empirical end points to pathways of toxicity. This requires the integration of in vitro and in vivo data with computational modeling. Test systems and bioanalytical technologies have made significant advances, but ensuring data reliability and relevance is an ongoing concern. The major challenge facing the new pathway approach is determining how to link observed network perturbations to phenotypic toxicity.
Collapse
Affiliation(s)
- Thomas Hartung
- Center
for Alternatives to Animal Testing (CAAT), Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland 21205, United States
- University
of Konstanz, CAAT-Europe, 78457 Konstanz, Germany
| | - Rex E. FitzGerald
- Swiss
Centre for Applied Human Toxicology, University
of Basel, 4055 Basel, Switzerland
| | - Paul Jennings
- Division
of Physiology, Department of Physiology and Medical Physics, Medical University of Innsbruck, 6020 Innsbruck, Austria
| | - Gary R. Mirams
- Centre
for Mathematical Medicine & Biology, School of Mathematical Sciences, University of Nottingham, Nottingham NG7 2RD, U.K.
| | - Manuel C. Peitsch
- Department
of Research and Development, Philip Morris
International, 2000 Neuchâtel, Switzerland
| | - Amin Rostami-Hodjegan
- Centre
for Applied Pharmacokinetic Research, University
of Manchester, Manchester M13 9PL, U.K.
- Simcyp
Limited (a Certara Company), Blades Enterprise
Centre, Sheffield S2 4SU, U.K.
| | - Imran Shah
- National
Center for Computational Toxicology, Research Triangle Park, North Carolina 27711, United States
| | - Martin F. Wilks
- Swiss
Centre for Applied Human Toxicology, University
of Basel, 4055 Basel, Switzerland
| | - Shana J. Sturla
- Department
of Health Sciences and Technology, ETH Zurich, 8092 Zurich, Switzerland
| |
Collapse
|
27
|
Corsi C, Cortesi M, Callisesi G, De Bie J, Napolitano C, Santoro A, Mortara D, Severi S. Noninvasive quantification of blood potassium concentration from ECG in hemodialysis patients. Sci Rep 2017; 7:42492. [PMID: 28198403 PMCID: PMC5309791 DOI: 10.1038/srep42492] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2016] [Accepted: 01/11/2017] [Indexed: 11/29/2022] Open
Abstract
Blood potassium concentration ([K+]) influences the electrocardiogram (ECG), particularly T-wave morphology. We developed a new method to quantify [K+] from T-wave analysis and tested its clinical applicability on data from dialysis patients, in whom [K+] varies significantly during the therapy. To elucidate the mechanism linking [K+] and T-wave, we also analysed data from long QT syndrome type 2 (LQT2) patients, testing the hypothesis that our method would have underestimated [K+] in these patients. Moreover, a computational model was used to explore the physiological processes underlying our estimator at the cellular level. We analysed 12-lead ECGs from 45 haemodialysis and 12 LQT2 patients. T-wave amplitude and downslope were calculated from the first two eigenleads. The T-wave slope-to-amplitude ratio (TS/A) was used as starting point for an ECG-based [K+] estimate (KECG). Leave-one-out cross-validation was performed. Agreement between KECG and reference [K+] from blood samples was promising (error: −0.09 ± 0.59 mM, absolute error: 0.46 ± 0.39 mM). The analysis on LQT2 patients, also supported by the outcome of computational analysis, reinforces our interpretation that, at the cellular level, delayed-rectifier potassium current is a main contributor of KECG correlation to blood [K+]. Following a comprehensive validation, this method could be effectively applied to monitor patients at risk for hyper/hypokalemia.
Collapse
Affiliation(s)
- Cristiana Corsi
- Department of Electrical, Electronic and Information Engineering "Guglielmo Marconi", University of Bologna, Cesena, Italy.,Health Sciences and Technology Interdepartmental Center for Industrial Research, University of Bologna, Cesena, Italy
| | - Marilisa Cortesi
- Department of Electrical, Electronic and Information Engineering "Guglielmo Marconi", University of Bologna, Cesena, Italy
| | - Giulia Callisesi
- Department of Electrical, Electronic and Information Engineering "Guglielmo Marconi", University of Bologna, Cesena, Italy
| | | | - Carlo Napolitano
- Molecular Cardiology, IRCCS Fondazione Salvatore Maugeri, Pavia, Italy
| | - Antonio Santoro
- Nephrology Dialysis, Hypertension Unit, Hospital Policlinico S.Orsola-Malpighi, Bologna, Italy
| | | | - Stefano Severi
- Department of Electrical, Electronic and Information Engineering "Guglielmo Marconi", University of Bologna, Cesena, Italy.,Health Sciences and Technology Interdepartmental Center for Industrial Research, University of Bologna, Cesena, Italy
| |
Collapse
|
28
|
Windley MJ, Abi-Gerges N, Fermini B, Hancox JC, Vandenberg JI, Hill AP. Measuring kinetics and potency of hERG block for CiPA. J Pharmacol Toxicol Methods 2017; 87:99-107. [PMID: 28192183 DOI: 10.1016/j.vascn.2017.02.017] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2016] [Revised: 01/25/2017] [Accepted: 02/07/2017] [Indexed: 12/20/2022]
Abstract
INTRODUCTION The Comprehensive in vitro Proarrhythmic Assay (CiPA) aims to update current cardiac safety testing to better evaluate arrhythmic risk. A central theme of CiPA is the use of in silico approaches to risk prediction incorporating models of drug binding to hERG. To parameterize these models, accurate in vitro measurement of potency and kinetics of block is required. The Ion Channel Working Group was tasked with: i) selecting a protocol that could measure kinetics of block and was easily implementable on automated platforms for future rollout in industry and ii) acquiring a reference dataset using the standardized protocol. METHODS Data were acquired using a 'step depolarisation' protocol using manual patch-clamp at ambient temperature. RESULTS Potency, kinetics and trapping characteristics of hERG block for the CiPA training panel of twelve drugs were measured. Timecourse of block and trapping characteristics could be reliably measured if the time constant for onset of block was between ~500ms and ~15s. Seven drugs, however had time courses of block faster than this cut-off. DISCUSSION Here we describe the implementation of the standardized protocol for measurement of kinetics and potency of hERG block for CiPA. The results highlight the challenges in identifying a single protocol to measure hERG block over a range of kinetics. The dataset from this study is being used by the In Silico Working Group to develop models of drug binding for risk prediction and is freely available as a 'gold standard' ambient temperature dataset to evaluate variability across high throughput platforms.
Collapse
Affiliation(s)
- Monique J Windley
- Molecular Cardiology and Biophysics Division, Victor Chang Cardiac Research Institute, 405 Liverpool Street, Sydney, NSW 2010, Australia; St. Vincent's Clinical School, University of New South Wales, Sydney, NSW 2052, Australia
| | | | - Bernard Fermini
- Coyne Scientific, LLC, 58 Edgewood Ave NE Atlanta, GA 30303, USA
| | - Jules C Hancox
- School of Physiology, Pharmacology and Neuroscience, University of Bristol, UK
| | - Jamie I Vandenberg
- Molecular Cardiology and Biophysics Division, Victor Chang Cardiac Research Institute, 405 Liverpool Street, Sydney, NSW 2010, Australia; St. Vincent's Clinical School, University of New South Wales, Sydney, NSW 2052, Australia
| | - Adam P Hill
- Molecular Cardiology and Biophysics Division, Victor Chang Cardiac Research Institute, 405 Liverpool Street, Sydney, NSW 2010, Australia; St. Vincent's Clinical School, University of New South Wales, Sydney, NSW 2052, Australia.
| |
Collapse
|
29
|
Dubois VFS, Casarotto E, Danhof M, Della Pasqua O. Pharmacokinetic-pharmacodynamic modelling of drug-induced QTc interval prolongation in man: prediction from in vitro human ether-à-go-go-related gene binding and functional inhibition assays and conscious dog studies. Br J Pharmacol 2016; 173:2819-32. [PMID: 27427789 DOI: 10.1111/bph.13558] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2015] [Revised: 06/23/2016] [Accepted: 06/30/2016] [Indexed: 12/19/2022] Open
Abstract
BACKGROUND AND PURPOSE Functional measures of human ether-à-go-go-related gene (hERG; Kv 11.1) channel inhibition have been prioritized as an in vitro screening tool for candidate molecules. However, it is unclear how these results can be translated to humans. Here, we explore how data on drug binding and functional inhibition in vitro relate to QT prolongation in vivo. Using cisapride, sotalol and moxifloxacin as paradigm compounds, we assessed the relationship between drug concentrations, binding, functional measures and in vivo effects in preclinical species and humans. EXPERIMENTAL APPROACH Pharmacokinetic-pharmacodynamic modelling was used to characterize the drug effects in hERG functional patch clamp, hERG radio-labelled dofetilide displacement experiments and QT interval in conscious dogs. Data were analysed in parallel to identify potential correlations between pharmacological activity in vitro and in vivo. KEY RESULTS An Emax model could not be used due to large variability in the functional patch clamp assay. Dofetilide displacement revealed that binding curves are unrelated to the in vivo potency estimates for QTc prolongation in dogs and humans. Mean in vitro potency estimates ranged from 99.9 nM for cisapride to 1030 μM for moxifloxacin. CONCLUSIONS AND IMPLICATIONS The lack of standardized protocols for in vitro assays leads to significant differences in experimental conditions, making the assessment of in vitro-in vivo correlations unreliable. Identification of an accurate safety window during the screening of candidate molecules requires a quantitative framework that disentangles system- from drug-specific properties under physiological conditions, enabling translation of the results to humans. Similar considerations will be relevant for the comprehensive in vitro pro-arrhythmia assay initiative.
Collapse
Affiliation(s)
- V F S Dubois
- Leiden Academic Centre for Drug Research, Division of Pharmacology, Leiden University, Leiden, The Netherlands
| | - E Casarotto
- Leiden Academic Centre for Drug Research, Division of Pharmacology, Leiden University, Leiden, The Netherlands
| | - M Danhof
- Leiden Academic Centre for Drug Research, Division of Pharmacology, Leiden University, Leiden, The Netherlands
| | - O Della Pasqua
- Leiden Academic Centre for Drug Research, Division of Pharmacology, Leiden University, Leiden, The Netherlands. .,Clinical Pharmacology Modelling and Simulation, GlaxoSmithKline, Uxbridge, UK. .,Clinical Pharmacology and Therapeutics, School of Life and Medical Sciences, University College London, London, UK.
| |
Collapse
|
30
|
Hill AP, Perry MD, Abi-Gerges N, Couderc JP, Fermini B, Hancox JC, Knollmann BC, Mirams GR, Skinner J, Zareba W, Vandenberg JI. Computational cardiology and risk stratification for sudden cardiac death: one of the grand challenges for cardiology in the 21st century. J Physiol 2016; 594:6893-6908. [PMID: 27060987 PMCID: PMC5134408 DOI: 10.1113/jp272015] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2015] [Accepted: 03/16/2016] [Indexed: 12/25/2022] Open
Abstract
Risk stratification in the context of sudden cardiac death has been acknowledged as one of the major challenges facing cardiology for the past four decades. In recent years, the advent of high performance computing has facilitated organ-level simulation of the heart, meaning we can now examine the causes, mechanisms and impact of cardiac dysfunction in silico. As a result, computational cardiology, largely driven by the Physiome project, now stands at the threshold of clinical utility in regards to risk stratification and treatment of patients at risk of sudden cardiac death. In this white paper, we outline a roadmap of what needs to be done to make this translational step, using the relatively well-developed case of acquired or drug-induced long QT syndrome as an exemplar case.
Collapse
Affiliation(s)
- Adam P Hill
- Victor Chang Cardiac Research Institute, 405 Liverpool Street, Darlinghurst, NSW, 2010, Australia.,St. Vincent's Clinical School, University of New South Wales, Sydney, NSW, 2052, Australia
| | - Matthew D Perry
- Victor Chang Cardiac Research Institute, 405 Liverpool Street, Darlinghurst, NSW, 2010, Australia.,St. Vincent's Clinical School, University of New South Wales, Sydney, NSW, 2052, Australia
| | - Najah Abi-Gerges
- AnaBios Corporation, 3030 Bunker Hill St., San Diego, CA, 92109, USA
| | | | - Bernard Fermini
- Global Safety Pharmacology, Pfizer Inc, MS8274-1347 Eastern Point Road, Groton, CT, 06340, USA
| | - Jules C Hancox
- School of Physiology, Pharmacology and Neuroscience, University of Bristol, Bristol, UK
| | - Bjorn C Knollmann
- Vanderbilt University School of Medicine, 1285 Medical Research Building IV, Nashville, Tennessee, 37232, USA
| | - Gary R Mirams
- Computational Biology, Department of Computer Science, University of Oxford, Oxford, United Kingdom
| | - Jon Skinner
- Cardiac Inherited Disease Group, Starship Hospital, Auckland, New Zealand
| | - Wojciech Zareba
- University of Rochester Medical Center, Rochester, NY, 14642, USA
| | - Jamie I Vandenberg
- Victor Chang Cardiac Research Institute, 405 Liverpool Street, Darlinghurst, NSW, 2010, Australia.,St. Vincent's Clinical School, University of New South Wales, Sydney, NSW, 2052, Australia
| |
Collapse
|
31
|
Colatsky T, Fermini B, Gintant G, Pierson JB, Sager P, Sekino Y, Strauss DG, Stockbridge N. The Comprehensive in Vitro Proarrhythmia Assay (CiPA) initiative - Update on progress. J Pharmacol Toxicol Methods 2016; 81:15-20. [PMID: 27282641 DOI: 10.1016/j.vascn.2016.06.002] [Citation(s) in RCA: 288] [Impact Index Per Article: 36.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2016] [Revised: 06/01/2016] [Accepted: 06/04/2016] [Indexed: 11/17/2022]
Abstract
The implementation of the ICH S7B and E14 guidelines has been successful in preventing the introduction of potentially torsadogenic drugs to the market, but it has also unduly constrained drug development by focusing on hERG block and QT prolongation as essential determinants of proarrhythmia risk. The Comprehensive in Vitro Proarrhythmia Assay (CiPA) initiative was established to develop a new paradigm for assessing proarrhythmic risk, building on the emergence of new technologies and an expanded understanding of torsadogenic mechanisms beyond hERG block. An international multi-disciplinary team of regulatory, industry and academic scientists are working together to develop and validate a set of predominantly nonclinical assays and methods that eliminate the need for the thorough-QT study and enable a more precise prediction of clinical proarrhythmia risk. The CiPA effort is led by a Steering Team that provides guidance, expertise and oversight to the various working groups and includes partners from US FDA, HESI, CSRC, SPS, EMA, Health Canada, Japan NIHS, and PMDA. The working groups address the three pillars of CiPA that evaluate drug effects on: 1) human ventricular ionic channel currents in heterologous expression systems, 2) in silico integration of cellular electrophysiologic effects based on ionic current effects, the ion channel effects, and 3) fully integrated biological systems (stem-cell-derived cardiac myocytes and the human ECG). This article provides an update on the progress of the initiative towards its target date of December 2017 for completing validation.
Collapse
Affiliation(s)
- Thomas Colatsky
- US FDA, 10903 New Hampshire Ave, Silver Spring, MD 20993, United States.
| | - Bernard Fermini
- Pfizer, Eastern Point Road MS 4083, Groton, CT 06340, United States.
| | - Gary Gintant
- AbbVie, R46R AP-9, 1 North Waukegan Rd, North Chicago, IL 60064-6118, United States.
| | - Jennifer B Pierson
- ILSI-Health and Environmental Sciences Institute, 1156 15th Street NW, Suite 200, Washington, DC 20005, United States.
| | - Philip Sager
- Stanford University, 719 Carolina St., San Francisco, CA 94107, United States.
| | - Yuko Sekino
- NIHS Japan, Kamiyoga 1-18-1, Setagaya-ku, Tokyo 158-8501, Japan.
| | - David G Strauss
- US FDA, 10903 New Hampshire Ave, Silver Spring, MD 20993, United States.
| | - Norman Stockbridge
- US FDA, 10903 New Hampshire Ave, Silver Spring, MD 20993, United States.
| |
Collapse
|
32
|
Windley MJ, Mann SA, Vandenberg JI, Hill AP. Temperature Effects on Kinetics of KV11.1 Drug Block Have Important Consequences for In Silico Proarrhythmic Risk Prediction. Mol Pharmacol 2016; 90:1-11. [PMID: 27190211 DOI: 10.1124/mol.115.103127] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2016] [Accepted: 05/11/2016] [Indexed: 01/08/2023] Open
Abstract
Drug block of voltage-gated potassium channel subtype 11.1 human ether-a-go-go related gene (Kv11.1) (hERG) channels, encoded by the KCNH2 gene, is associated with reduced repolarization of the cardiac action potential and is the predominant cause of acquired long QT syndrome that can lead to fatal cardiac arrhythmias. Current safety guidelines require that potency of KV11.1 block is assessed in the preclinical phase of drug development. However, not all drugs that block KV11.1 are proarrhythmic, meaning that screening on the basis of equilibrium measures of block can result in high attrition of potentially low-risk drugs. The basis of the next generation of drug-screening approaches is set to be in silico risk prediction, informed by in vitro mechanistic descriptions of drug binding, including measures of the kinetics of block. A critical issue in this regard is characterizing the temperature dependence of drug binding. Specifically, it is important to address whether kinetics relevant to physiologic temperatures can be inferred or extrapolated from in vitro data gathered at room temperature in high-throughout systems. Here we present the first complete study of the temperature-dependent kinetics of block and unblock of a proarrhythmic drug, cisapride, to KV11.1. Our data highlight a complexity to binding that manifests at higher temperatures and can be explained by accumulation of an intermediate, non-blocking encounter-complex. These results suggest that for cisapride, physiologically relevant kinetic parameters cannot be simply extrapolated from those measured at lower temperatures; rather, data gathered at physiologic temperatures should be used to constrain in silico models that may be used for proarrhythmic risk prediction.
Collapse
Affiliation(s)
- Monique J Windley
- Computational Cardiology, Victor Chang Cardiac Research Institute, Darlinghurst, Australia (M.J.W., S.A.M., J.I.V., A.P.H.); and St. Vincent's Clinical School, University of New South Wales, Darlinghurst, Australia (S.A.M., J.I.V., A.P.H.)
| | - Stefan A Mann
- Computational Cardiology, Victor Chang Cardiac Research Institute, Darlinghurst, Australia (M.J.W., S.A.M., J.I.V., A.P.H.); and St. Vincent's Clinical School, University of New South Wales, Darlinghurst, Australia (S.A.M., J.I.V., A.P.H.)
| | - Jamie I Vandenberg
- Computational Cardiology, Victor Chang Cardiac Research Institute, Darlinghurst, Australia (M.J.W., S.A.M., J.I.V., A.P.H.); and St. Vincent's Clinical School, University of New South Wales, Darlinghurst, Australia (S.A.M., J.I.V., A.P.H.)
| | - Adam P Hill
- Computational Cardiology, Victor Chang Cardiac Research Institute, Darlinghurst, Australia (M.J.W., S.A.M., J.I.V., A.P.H.); and St. Vincent's Clinical School, University of New South Wales, Darlinghurst, Australia (S.A.M., J.I.V., A.P.H.)
| |
Collapse
|
33
|
Li Z, Dutta S, Sheng J, Tran PN, Wu W, Colatsky T. A temperature-dependent in silico model of the human ether-à-go-go-related (hERG) gene channel. J Pharmacol Toxicol Methods 2016; 81:233-9. [PMID: 27178106 DOI: 10.1016/j.vascn.2016.05.005] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2016] [Revised: 04/20/2016] [Accepted: 05/09/2016] [Indexed: 11/29/2022]
Abstract
INTRODUCTION Current regulatory guidelines for assessing the risk of QT prolongation include in vitro assays assessing drug effects on the human ether-à-go-go-related (hERG; also known as Kv11.1) channel expressed in cell lines. These assays are typically conducted at room temperature to promote the ease and stability of recording hERG currents. However, the new Comprehensive in vitro Proarrhythmia Assay (CiPA) paradigm proposes to use an in silico model of the human ventricular myocyte to assess risk, requiring as input hERG channel pharmacology data obtained at physiological temperatures. To accommodate current industry safety pharmacology practices for measuring hERG channel activity, an in silico model of hERG channel that allows for the extrapolation of hERG assay data across different temperatures is desired. Because temperature may have an effect on both channel gating and drug binding rate, such models may need to have two components: a base model dealing with temperature-dependent gating changes without drug, and a pharmacodynamic component simulating temperature-dependent drug binding kinetics. As a first step, a base mode that can capture temperature effects on hERG channel gating without drug is needed. METHODS AND RESULTS To meet this need for a temperature-dependent base model, a Markov model of the hERG channel with state transition rates explicitly dependent on temperature was developed and calibrated using data from a variety of published experiments conducted over a range of temperatures. The model was able to reproduce observed temperature-dependent changes in key channel gating properties and also to predict the results obtained in independent sets of new experiments. DISCUSSION This new temperature-sensitive model of hERG gating represents an attempt to improve the predictivity of safety pharmacology testing by enabling the translation of room temperature hERG assay data to more physiological conditions. With further development, this model can be incorporated into the CiPA paradigm and also be used as a tool for developing insights into the thermodynamics of hERG channel gating mechanisms and the temperature-dependence of hERG channel block by drugs.
Collapse
Affiliation(s)
- Zhihua Li
- Division of Applied Regulatory Science, Office of Clinical Pharmacology, Office of Translational Sciences, Center for Drug Evaluation and Research, Food and Drug Administration, United States.
| | - Sara Dutta
- Division of Applied Regulatory Science, Office of Clinical Pharmacology, Office of Translational Sciences, Center for Drug Evaluation and Research, Food and Drug Administration, United States
| | - Jiansong Sheng
- Division of Applied Regulatory Science, Office of Clinical Pharmacology, Office of Translational Sciences, Center for Drug Evaluation and Research, Food and Drug Administration, United States
| | - Phu N Tran
- Division of Applied Regulatory Science, Office of Clinical Pharmacology, Office of Translational Sciences, Center for Drug Evaluation and Research, Food and Drug Administration, United States
| | - Wendy Wu
- Division of Applied Regulatory Science, Office of Clinical Pharmacology, Office of Translational Sciences, Center for Drug Evaluation and Research, Food and Drug Administration, United States
| | - Thomas Colatsky
- Division of Applied Regulatory Science, Office of Clinical Pharmacology, Office of Translational Sciences, Center for Drug Evaluation and Research, Food and Drug Administration, United States
| |
Collapse
|
34
|
McCauley M, Vallabhajosyula S, Darbar D. Proarrhythmic and Torsadogenic Effects of Potassium Channel Blockers in Patients. Card Electrophysiol Clin 2016; 8:481-93. [PMID: 27261836 DOI: 10.1016/j.ccep.2016.02.009] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
The most common arrhythmia requiring drug treatment is atrial fibrillation (AF), which affects 2 to 5 million Americans and continues to be a major cause of morbidity and increased mortality. Despite recent advances in catheter-based and surgical therapies, antiarrhythmic drugs continue to be the mainstay of therapy for most patients with symptomatic AF. However, many antiarrhythmics block the rapid component of the cardiac delayed rectifier potassium current (IKr) as a major mechanism of action, and marked QT prolongation and pause-dependent polymorphic ventricular tachycardia (torsades de pointes) are major class toxicities.
Collapse
Affiliation(s)
- Mark McCauley
- Division of Cardiology, Department of Medicine, University of Illinois at Chicago, 840 South Wood Street, Suite 920 (MC715), Chicago, IL 60612, USA
| | - Sharath Vallabhajosyula
- Division of Cardiology, Department of Medicine, University of Illinois at Chicago, 840 South Wood Street, Suite 920 (MC715), Chicago, IL 60612, USA
| | - Dawood Darbar
- Division of Cardiology, Department of Medicine, University of Illinois at Chicago, 840 South Wood Street, Suite 920 (MC715), Chicago, IL 60612, USA.
| |
Collapse
|
35
|
|
36
|
Trayanova NA, Chang KC. How computer simulations of the human heart can improve anti-arrhythmia therapy. J Physiol 2016; 594:2483-502. [PMID: 26621489 DOI: 10.1113/jp270532] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2015] [Accepted: 11/25/2015] [Indexed: 01/26/2023] Open
Abstract
Over the last decade, the state-of-the-art in cardiac computational modelling has progressed rapidly. The electrophysiological function of the heart can now be simulated with a high degree of detail and accuracy, opening the doors for simulation-guided approaches to anti-arrhythmic drug development and patient-specific therapeutic interventions. In this review, we outline the basic methodology for cardiac modelling, which has been developed and validated over decades of research. In addition, we present several recent examples of how computational models of the human heart have been used to address current clinical problems in cardiac electrophysiology. We will explore the use of simulations to improve anti-arrhythmic pacing and defibrillation interventions; to predict optimal sites for clinical ablation procedures; and to aid in the understanding and selection of arrhythmia risk markers. Together, these studies illustrate how the tremendous advances in cardiac modelling are poised to revolutionize medical treatment and prevention of arrhythmia.
Collapse
Affiliation(s)
- Natalia A Trayanova
- Johns Hopkins School of Medicine, Baltimore, MD, 21205, USA.,Johns Hopkins University, Baltimore, MD, 21218, USA
| | - Kelly C Chang
- Johns Hopkins School of Medicine, Baltimore, MD, 21205, USA
| |
Collapse
|
37
|
Champeroux P, Le Guennec JY, Jude S, Laigot C, Maurin A, Sola ML, Fowler JSL, Richard S, Thireau J. The high frequency relationship: implications for torsadogenic hERG blockers. Br J Pharmacol 2016; 173:601-12. [PMID: 26589499 DOI: 10.1111/bph.13391] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2015] [Revised: 11/11/2015] [Accepted: 11/17/2015] [Indexed: 11/30/2022] Open
Abstract
BACKGROUND AND PURPOSE Ventricular arrhythmias induced by human ether-a-go-go related gene (hERG; Kv 11.1 channel) blockers are a consequence of alterations in ventricular repolarisation in association with high-frequency (HF) oscillations, which act as a primary trigger; the autonomic nervous system plays a modulatory role. In the present study, we investigated the role of β1 -adrenoceptors in the HF relationship between magnitude of heart rate and QT interval changes within discrete 10 s intervals (sorted into 5 bpm heart rate increments) and its implications for torsadogenic hERG blockers. EXPERIMENTAL APPROACH The HF relationship was studied under conditions of autonomic blockade with atenolol (β1 -adrenoceptor blocker) in the absence or presence of five hERG blockers in beagle dogs. In total, the effects of 14 hERG blockers on the HF relationship were investigated. KEY RESULTS All the torsadogenic hERG blockers tested caused a vertical shift in the HF relationship, while hERG blockers associated with a low risk of Torsades de Pointes did not cause any vertical shift. Atenolol completely prevented the effects four torsadogenic agents (quinidine, thioridazine, risperidone and terfenadine) on the HF relationship, but only partially reduced those of dofetilide, leading to the characterization of two types of torsadogenic agent. CONCLUSIONS AND IMPLICATIONS Analysis of the vertical shift in the HF relationship demonstrated that signs of transient sympathetic activation during HF oscillations in the presence of torsadogenic hERG blockers are mediated by β1 -adrenoceptors. We suggest the HF relationship as a new biomarker for assessing Torsades de pointes liability, with potential implications in both preclinical studies and the clinic.
Collapse
Affiliation(s)
- P Champeroux
- Centre de Recherches Biologiques, CERB, Chemin de Montifault, 18800, Baugy, France
| | - J Y Le Guennec
- Laboratoire PHYMEDEXP, Physiologie et Médecine Expérimentale, Cœur et Muscles, INSERM U1046, CNRS UMR 9214, Université de Montpellier, CHU Arnaud de Villeneuve, 371 Avenue du doyen G. Giraud, 34295, Montpellier cedex 05, France
| | - S Jude
- Centre de Recherches Biologiques, CERB, Chemin de Montifault, 18800, Baugy, France
| | - C Laigot
- Centre de Recherches Biologiques, CERB, Chemin de Montifault, 18800, Baugy, France
| | - A Maurin
- Centre de Recherches Biologiques, CERB, Chemin de Montifault, 18800, Baugy, France
| | - M L Sola
- Centre de Recherches Biologiques, CERB, Chemin de Montifault, 18800, Baugy, France
| | - J S L Fowler
- Centre de Recherches Biologiques, CERB, Chemin de Montifault, 18800, Baugy, France
| | - S Richard
- Centre de Recherches Biologiques, CERB, Chemin de Montifault, 18800, Baugy, France
| | - J Thireau
- Laboratoire PHYMEDEXP, Physiologie et Médecine Expérimentale, Cœur et Muscles, INSERM U1046, CNRS UMR 9214, Université de Montpellier, CHU Arnaud de Villeneuve, 371 Avenue du doyen G. Giraud, 34295, Montpellier cedex 05, France
| |
Collapse
|
38
|
Lee W, Mann SA, Windley MJ, Imtiaz MS, Vandenberg JI, Hill AP. In silico assessment of kinetics and state dependent binding properties of drugs causing acquired LQTS. PROGRESS IN BIOPHYSICS AND MOLECULAR BIOLOGY 2015; 120:89-99. [PMID: 26713558 DOI: 10.1016/j.pbiomolbio.2015.12.005] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/15/2015] [Revised: 11/06/2015] [Accepted: 12/16/2015] [Indexed: 11/24/2022]
Abstract
The Kv11.1 or hERG potassium channel is responsible for one of the major repolarising currents (IKr) in cardiac myocytes. Drug binding to hERG can result in reduction in IKr, action potential prolongation, acquired long QT syndrome and fatal cardiac arrhythmias. The current guidelines for pre-clinical assessment of drugs in development is based on the measurement of the drug concentration that causes 50% current block, i.e., IC50. However, drugs with the same apparent IC50 may have very different kinetics of binding and unbinding, as well as different affinities for the open and inactivated states of Kv11.1. Therefore, IC50 measurements may not reflect the true risk of drug induced arrhythmias. Here we have used an in silico approach to test the hypothesis that drug binding kinetics and differences in state-dependent affinity will influence the extent of cardiac action potential prolongation independent of apparent IC50 values. We found, in general that drugs with faster overall kinetics and drugs with higher affinity for the open state relative to the inactivated state cause more action potential prolongation. These characteristics of drug-hERG interaction are likely to be more arrhythmogenic but cannot be predicted by IC50 measurement alone. Our results suggest that the pre-clinical assessment of Kv11.1-drug interactions should include descriptions of the kinetics and state dependence of drug binding. Further, incorporation of this information into sophisticated in silico models should be able to better predict arrhythmia risk and therefore more accurately assess safety of new drugs in development.
Collapse
Affiliation(s)
- William Lee
- Victor Chang Cardiac Research Institute, 405 Liverpool Street, Darlinghurst, NSW 2010, Australia; St Vincent's Clinical School, University of New South Wales, NSW 2052, Australia
| | - Stefan A Mann
- Victor Chang Cardiac Research Institute, 405 Liverpool Street, Darlinghurst, NSW 2010, Australia; St Vincent's Clinical School, University of New South Wales, NSW 2052, Australia
| | - Monique J Windley
- Victor Chang Cardiac Research Institute, 405 Liverpool Street, Darlinghurst, NSW 2010, Australia
| | - Mohammad S Imtiaz
- Victor Chang Cardiac Research Institute, 405 Liverpool Street, Darlinghurst, NSW 2010, Australia; St Vincent's Clinical School, University of New South Wales, NSW 2052, Australia
| | - Jamie I Vandenberg
- Victor Chang Cardiac Research Institute, 405 Liverpool Street, Darlinghurst, NSW 2010, Australia; St Vincent's Clinical School, University of New South Wales, NSW 2052, Australia
| | - Adam P Hill
- Victor Chang Cardiac Research Institute, 405 Liverpool Street, Darlinghurst, NSW 2010, Australia; St Vincent's Clinical School, University of New South Wales, NSW 2052, Australia.
| |
Collapse
|
39
|
Veroli GYD, Fornari C, Goldlust I, Mills G, Koh SB, Bramhall JL, Richards FM, Jodrell DI. An automated fitting procedure and software for dose-response curves with multiphasic features. Sci Rep 2015; 5:14701. [PMID: 26424192 PMCID: PMC4589737 DOI: 10.1038/srep14701] [Citation(s) in RCA: 109] [Impact Index Per Article: 12.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2015] [Accepted: 09/07/2015] [Indexed: 01/27/2023] Open
Abstract
In cancer pharmacology (and many other areas), most dose-response curves are satisfactorily described by a classical Hill equation (i.e. 4 parameters logistical). Nevertheless, there are instances where the marked presence of more than one point of inflection, or the presence of combined agonist and antagonist effects, prevents straight-forward modelling of the data via a standard Hill equation. Here we propose a modified model and automated fitting procedure to describe dose-response curves with multiphasic features. The resulting general model enables interpreting each phase of the dose-response as an independent dose-dependent process. We developed an algorithm which automatically generates and ranks dose-response models with varying degrees of multiphasic features. The algorithm was implemented in new freely available Dr Fit software (sourceforge.net/projects/drfit/). We show how our approach is successful in describing dose-response curves with multiphasic features. Additionally, we analysed a large cancer cell viability screen involving 11650 dose-response curves. Based on our algorithm, we found that 28% of cases were better described by a multiphasic model than by the Hill model. We thus provide a robust approach to fit dose-response curves with various degrees of complexity, which, together with the provided software implementation, should enable a wide audience to easily process their own data.
Collapse
Affiliation(s)
| | | | - Ian Goldlust
- CRUK Cambridge Institute, University of Cambridge, UK
- NIH Chemical Genomics Center, National Institutes of Health, Bethesda, USA
| | - Graham Mills
- CRUK Cambridge Institute, University of Cambridge, UK
| | | | - Jo L Bramhall
- CRUK Cambridge Institute, University of Cambridge, UK
| | | | | |
Collapse
|
40
|
Yu Z, van Veldhoven JPD, Louvel J, ’t Hart IME, Rook MB, van der Heyden MAG, Heitman LH, IJzerman AP. Structure–Affinity Relationships (SARs) and Structure–Kinetics Relationships (SKRs) of Kv11.1 Blockers. J Med Chem 2015; 58:5916-29. [DOI: 10.1021/acs.jmedchem.5b00518] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Affiliation(s)
- Zhiyi Yu
- Division
of Medicinal Chemistry, Leiden Academic Centre for Drug Research, Leiden University, 2300 RA Leiden, The Netherlands
| | - Jacobus P. D. van Veldhoven
- Division
of Medicinal Chemistry, Leiden Academic Centre for Drug Research, Leiden University, 2300 RA Leiden, The Netherlands
| | - Julien Louvel
- Division
of Medicinal Chemistry, Leiden Academic Centre for Drug Research, Leiden University, 2300 RA Leiden, The Netherlands
| | - Ingrid M. E. ’t Hart
- Division
of Medicinal Chemistry, Leiden Academic Centre for Drug Research, Leiden University, 2300 RA Leiden, The Netherlands
| | - Martin B. Rook
- Department of Medical Physiology, Division Heart & Lungs, University Medical Centre Utrecht, 3584 CM Utrecht, The Netherlands
| | - Marcel A. G. van der Heyden
- Department of Medical Physiology, Division Heart & Lungs, University Medical Centre Utrecht, 3584 CM Utrecht, The Netherlands
| | - Laura H. Heitman
- Division
of Medicinal Chemistry, Leiden Academic Centre for Drug Research, Leiden University, 2300 RA Leiden, The Netherlands
| | - Adriaan P. IJzerman
- Division
of Medicinal Chemistry, Leiden Academic Centre for Drug Research, Leiden University, 2300 RA Leiden, The Netherlands
| |
Collapse
|
41
|
Champeroux P, Thireau J, Judé S, Laigot-Barbé C, Maurin A, Sola ML, Fowler JSL, Richard S, Le Guennec JY. Short-term variability in QT interval and ventricular arrhythmias induced by dofetilide are dependent on high-frequency autonomic oscillations. Br J Pharmacol 2015; 172:2878-91. [PMID: 25625756 PMCID: PMC4439882 DOI: 10.1111/bph.13093] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2014] [Revised: 01/15/2015] [Accepted: 01/20/2015] [Indexed: 01/13/2023] Open
Abstract
Background and Purpose The present study was undertaken to investigate an effect of dofetilide, a potent arrhythmic blocker of the voltage-gated K+ channel, hERG, on cardiac autonomic control. Combined with effects on ardiomyocytes, these properties could influence its arrhythmic potency. Experimental Approach The short-term variability of beat-to-beat QT interval (STVQT), induced by dofetilide is a strong surrogate of Torsades de pointes liability. Involvement of autonomic modulation in STVQT was investigated in healthy cynomolgus monkeys and beagle dogs by power spectral analysis under conditions of autonomic blockade with hexamethonium. Key Results Increase in STVQT induced by dofetilide in monkeys and dogs was closely associated with an enhancement of endogenous heart rate and QT interval high-frequency (HF) oscillations. These effects were fully suppressed under conditions of autonomic blockade with hexamethonium. Ventricular arrhythmias, including Torsades de pointes in monkeys, were prevented in both species when HF oscillations were suppressed by autonomic blockade. Similar enhancements of heart rate HF oscillations were found in dogs with other hERG blockers described as causing Torsades de pointes in humans. Conclusions and Implications These results demonstrate for the first time that beat-to-beat ventricular repolarization variability and ventricular arrhythmias induced by dofetilide are dependent on endogenous HF autonomic oscillations in heart rate. When combined with evidence of hERG-blocking properties, enhancement of endogenous HF oscillations in heart rate could constitute an earlier and more sensitive biomarker than STVQT for Torsades de pointes liability, applicable to preclinical regulatory studies conducted in healthy animals.
Collapse
Affiliation(s)
- P Champeroux
- Centre de Recherches Biologiques, CERB, Baugy, France
| | - J Thireau
- Centre de Recherches Biologiques, CERB, Baugy, France
| | - S Judé
- Centre de Recherches Biologiques, CERB, Baugy, France
| | | | - A Maurin
- Centre de Recherches Biologiques, CERB, Baugy, France
| | - M L Sola
- Centre de Recherches Biologiques, CERB, Baugy, France
| | - J S L Fowler
- Centre de Recherches Biologiques, CERB, Baugy, France
| | - S Richard
- Centre de Recherches Biologiques, CERB, Baugy, France
| | | |
Collapse
|
42
|
Mistry HB, Davies MR, Di Veroli GY. A new classifier-based strategy for in-silico ion-channel cardiac drug safety assessment. Front Pharmacol 2015; 6:59. [PMID: 25852560 PMCID: PMC4371651 DOI: 10.3389/fphar.2015.00059] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2014] [Accepted: 03/08/2015] [Indexed: 11/13/2022] Open
Abstract
There is currently a strong interest in using high-throughput in-vitro ion-channel screening data to make predictions regarding the cardiac toxicity potential of a new compound in both animal and human studies. A recent FDA think tank encourages the use of biophysical mathematical models of cardiac myocytes for this prediction task. However, it remains unclear whether this approach is the most appropriate. Here we examine five literature data-sets that have been used to support the use of four different biophysical models and one statistical model for predicting cardiac toxicity in numerous species using various endpoints. We propose a simple model that represents the balance between repolarisation and depolarisation forces and compare the predictive power of the model against the original results (leave-one-out cross-validation). Our model showed equivalent performance when compared to the four biophysical models and one statistical model. We therefore conclude that this approach should be further investigated in the context of early cardiac safety screening when in-vitro potency data is generated.
Collapse
Affiliation(s)
- Hitesh B Mistry
- Manchester Pharmacy School, University of Manchester Manchester, UK
| | | | | |
Collapse
|
43
|
Yuan Y, Bai X, Luo C, Wang K, Zhang H. The virtual heart as a platform for screening drug cardiotoxicity. Br J Pharmacol 2015; 172:5531-47. [PMID: 25363597 PMCID: PMC4667856 DOI: 10.1111/bph.12996] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2014] [Revised: 10/23/2014] [Accepted: 10/28/2014] [Indexed: 01/01/2023] Open
Abstract
To predict the safety of a drug at an early stage in its development is a major challenge as there is a lack of in vitro heart models that correlate data from preclinical toxicity screening assays with clinical results. A biophysically detailed computer model of the heart, the virtual heart, provides a powerful tool for simulating drug–ion channel interactions and cardiac functions during normal and disease conditions and, therefore, provides a powerful platform for drug cardiotoxicity screening. In this article, we first review recent progress in the development of theory on drug–ion channel interactions and mathematical modelling. Then we propose a family of biomarkers that can quantitatively characterize the actions of a drug on the electrical activity of the heart at multi‐physical scales including cellular and tissue levels. We also conducted some simulations to demonstrate the application of the virtual heart to assess the pro‐arrhythmic effects of cisapride and amiodarone. Using the model we investigated the mechanisms responsible for the differences between the two drugs on pro‐arrhythmogenesis, even though both prolong the QT interval of ECGs. Several challenges for further development of a virtual heart as a platform for screening drug cardiotoxicity are discussed. Linked Articles This article is part of a themed section on Chinese Innovation in Cardiovascular Drug Discovery. To view the other articles in this section visit http://dx.doi.org/10.1111/bph.2015.172.issue-23
Collapse
Affiliation(s)
- Yongfeng Yuan
- School of Computer Science and Technology, Harbin Institute of Technology, Harbin, China
| | - Xiangyun Bai
- School of Computer Science and Technology, Harbin Institute of Technology, Harbin, China
| | - Cunjin Luo
- School of Computer Science and Technology, Harbin Institute of Technology, Harbin, China
| | - Kuanquan Wang
- School of Computer Science and Technology, Harbin Institute of Technology, Harbin, China
| | - Henggui Zhang
- School of Computer Science and Technology, Harbin Institute of Technology, Harbin, China.,Biological Physics Group, School of Physics and Astronomy, The University of Manchester, Manchester, UK
| |
Collapse
|
44
|
Yu Z, IJzerman AP, Heitman LH. Kv 11.1 (hERG)-induced cardiotoxicity: a molecular insight from a binding kinetics study of prototypical Kv 11.1 (hERG) inhibitors. Br J Pharmacol 2014; 172:940-55. [PMID: 25296617 DOI: 10.1111/bph.12967] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2014] [Revised: 09/08/2014] [Accepted: 09/23/2014] [Indexed: 12/24/2022] Open
Abstract
BACKGROUND AND PURPOSE Drug-induced arrhythmia due to blockade of the Kv 11.1 channel (also known as the hERG K(+) channel) is a frequent side effect. Previous studies have primarily focused on equilibrium parameters, i.e. affinity or potency, of drug candidates at the channel. The aim of this study was to determine the kinetics of the interaction with the channel for a number of known Kv 11.1 blockers and to explore a possible correlation with the affinity or physicochemical properties of these compounds. EXPERIMENTAL APPROACH The affinity and kinetic parameters of 15 prototypical Kv 11.1 inhibitors were evaluated in a number of [(3) H]-dofetilide binding assays. The lipophilicity (logKW - C8 ) and membrane partitioning (logKW - IAM ) of these compounds were determined by means of HPLC analysis. KEY RESULTS A novel [(3) H]-dofetilide competition association assay was set up and validated, which allowed us to determine the binding kinetics of the Kv 11.1 blockers used in this study. Interestingly, the compounds' affinities (Ki values) were correlated to their association rates rather than dissociation rates. Overall lipophilicity or membrane partitioning of the compounds were not correlated to their affinity or rate constants for the channel. CONCLUSIONS AND IMPLICATIONS A compound's affinity for the Kv 11.1 channel is determined by its rate of association with the channel, while overall lipophilicity and membrane affinity are not. In more general terms, our findings provide novel insights into the mechanism of action for a compound's activity at the Kv 11.1 channel. This may help to elucidate how Kv 11.1-induced cardiotoxicity is governed and how it can be circumvented in the future.
Collapse
Affiliation(s)
- Z Yu
- Division of Medicinal Chemistry, Leiden Academic Centre for Drug Research, Leiden University, Leiden, The Netherlands
| | | | | |
Collapse
|
45
|
Linder T, Saxena P, Timin E, Hering S, Stary-Weinzinger A. Structural Insights into Trapping and Dissociation of Small Molecules in K+ Channels. J Chem Inf Model 2014; 54:3218-28. [DOI: 10.1021/ci500353r] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Tobias Linder
- Department for Pharmacology and Toxicology, University of Vienna, Althanstraße 14, 1090 Vienna, Austria
| | - Priyanka Saxena
- Department for Pharmacology and Toxicology, University of Vienna, Althanstraße 14, 1090 Vienna, Austria
| | - Eugen Timin
- Department for Pharmacology and Toxicology, University of Vienna, Althanstraße 14, 1090 Vienna, Austria
| | - Steffen Hering
- Department for Pharmacology and Toxicology, University of Vienna, Althanstraße 14, 1090 Vienna, Austria
| | - Anna Stary-Weinzinger
- Department for Pharmacology and Toxicology, University of Vienna, Althanstraße 14, 1090 Vienna, Austria
| |
Collapse
|
46
|
Tong WC, Ghouri I, Taggart MJ. Computational modeling of inhibition of voltage-gated Ca channels: identification of different effects on uterine and cardiac action potentials. Front Physiol 2014; 5:399. [PMID: 25360118 PMCID: PMC4199256 DOI: 10.3389/fphys.2014.00399] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2014] [Accepted: 09/26/2014] [Indexed: 11/13/2022] Open
Abstract
The uterus and heart share the important physiological feature whereby contractile activation of the muscle tissue is regulated by the generation of periodic, spontaneous electrical action potentials (APs). Preterm birth arising from premature uterine contractions is a major complication of pregnancy and there remains a need to pursue avenues of research that facilitate the use of drugs, tocolytics, to limit these inappropriate contractions without deleterious actions on cardiac electrical excitation. A novel approach is to make use of mathematical models of uterine and cardiac APs, which incorporate many ionic currents contributing to the AP forms, and test the cell-specific responses to interventions. We have used three such models-of uterine smooth muscle cells (USMC), cardiac sinoatrial node cells (SAN), and ventricular cells-to investigate the relative effects of reducing two important voltage-gated Ca currents-the L-type (ICaL) and T-type (ICaT) Ca currents. Reduction of ICaL (10%) alone, or ICaT (40%) alone, blunted USMC APs with little effect on ventricular APs and only mild effects on SAN activity. Larger reductions in either current further attenuated the USMC APs but with also greater effects on SAN APs. Encouragingly, a combination of ICaL and ICaT reduction did blunt USMC APs as intended with little detriment to APs of either cardiac cell type. Subsequent overlapping maps of ICaL and ICaT inhibition profiles from each model revealed a range of combined reductions of ICaL and ICaT over which an appreciable diminution of USMC APs could be achieved with no deleterious action on cardiac SAN or ventricular APs. This novel approach illustrates the potential for computational biology to inform us of possible uterine and cardiac cell-specific mechanisms. Incorporating such computational approaches in future studies directed at designing new, or repurposing existing, tocolytics will be beneficial for establishing a desired uterine specificity of action.
Collapse
Affiliation(s)
- Wing-Chiu Tong
- Institute of Cellular Medicine, Newcastle UniversityNewcastle upon Tyne, UK
| | | | - Michael J. Taggart
- Institute of Cellular Medicine, Newcastle UniversityNewcastle upon Tyne, UK
| |
Collapse
|
47
|
Sadrieh A, Domanski L, Pitt-Francis J, Mann SA, Hodkinson EC, Ng CA, Perry MD, Taylor JA, Gavaghan D, Subbiah RN, Vandenberg JI, Hill AP. Multiscale cardiac modelling reveals the origins of notched T waves in long QT syndrome type 2. Nat Commun 2014; 5:5069. [PMID: 25254353 DOI: 10.1038/ncomms6069] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2014] [Accepted: 08/26/2014] [Indexed: 01/08/2023] Open
Abstract
The heart rhythm disorder long QT syndrome (LQTS) can result in sudden death in the young or remain asymptomatic into adulthood. The features of the surface electrocardiogram (ECG), a measure of the electrical activity of the heart, can be equally variable in LQTS patients, posing well-described diagnostic dilemmas. Here we report a correlation between QT interval prolongation and T-wave notching in LQTS2 patients and use a novel computational framework to investigate how individual ionic currents, as well as cellular and tissue level factors, contribute to notched T waves. Furthermore, we show that variable expressivity of ECG features observed in LQTS2 patients can be explained by as little as 20% variation in the levels of ionic conductances that contribute to repolarization reserve. This has significant implications for interpretation of whole-genome sequencing data and underlies the importance of interpreting the entire molecular signature of disease in any given individual.
Collapse
Affiliation(s)
- Arash Sadrieh
- 1] Division of Molecular Cardiology and Biophysics, Victor Chang Cardiac Research Institute, 405 Liverpool Street, Darlinghurst, New South Wales 2010, Australia [2] St Vincent's Clinical School, University of New South Wales, Sydney, New South Wales 2052, Australia
| | - Luke Domanski
- CSIRO eResearch and Computational and Simulation Sciences, Canberra, Australian Capital Territory 2601, Australia
| | - Joe Pitt-Francis
- Department of Computer Science, University of Oxford, Oxford OX1 3QD, UK
| | - Stefan A Mann
- 1] Division of Molecular Cardiology and Biophysics, Victor Chang Cardiac Research Institute, 405 Liverpool Street, Darlinghurst, New South Wales 2010, Australia [2] St Vincent's Clinical School, University of New South Wales, Sydney, New South Wales 2052, Australia
| | - Emily C Hodkinson
- 1] Division of Molecular Cardiology and Biophysics, Victor Chang Cardiac Research Institute, 405 Liverpool Street, Darlinghurst, New South Wales 2010, Australia [2] St Vincent's Clinical School, University of New South Wales, Sydney, New South Wales 2052, Australia
| | - Chai-Ann Ng
- 1] Division of Molecular Cardiology and Biophysics, Victor Chang Cardiac Research Institute, 405 Liverpool Street, Darlinghurst, New South Wales 2010, Australia [2] St Vincent's Clinical School, University of New South Wales, Sydney, New South Wales 2052, Australia
| | - Matthew D Perry
- 1] Division of Molecular Cardiology and Biophysics, Victor Chang Cardiac Research Institute, 405 Liverpool Street, Darlinghurst, New South Wales 2010, Australia [2] St Vincent's Clinical School, University of New South Wales, Sydney, New South Wales 2052, Australia
| | - John A Taylor
- CSIRO eResearch and Computational and Simulation Sciences, Canberra, Australian Capital Territory 2601, Australia
| | - David Gavaghan
- Department of Computer Science, University of Oxford, Oxford OX1 3QD, UK
| | - Rajesh N Subbiah
- 1] Division of Molecular Cardiology and Biophysics, Victor Chang Cardiac Research Institute, 405 Liverpool Street, Darlinghurst, New South Wales 2010, Australia [2] St Vincent's Clinical School, University of New South Wales, Sydney, New South Wales 2052, Australia
| | - Jamie I Vandenberg
- 1] Division of Molecular Cardiology and Biophysics, Victor Chang Cardiac Research Institute, 405 Liverpool Street, Darlinghurst, New South Wales 2010, Australia [2] St Vincent's Clinical School, University of New South Wales, Sydney, New South Wales 2052, Australia
| | - Adam P Hill
- 1] Division of Molecular Cardiology and Biophysics, Victor Chang Cardiac Research Institute, 405 Liverpool Street, Darlinghurst, New South Wales 2010, Australia [2] St Vincent's Clinical School, University of New South Wales, Sydney, New South Wales 2052, Australia
| |
Collapse
|
48
|
Kleiman RB, Shah RR, Morganroth J. Replacing the thorough QT study: reflections of a baby in the bath water. Br J Clin Pharmacol 2014; 78:195-201. [PMID: 24286381 PMCID: PMC4137815 DOI: 10.1111/bcp.12296] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2013] [Accepted: 11/21/2013] [Indexed: 01/03/2023] Open
|
49
|
Fijorek K, Tanner FC, Stähli BE, Gielerak G, Krzesinski P, Uzieblo-Zyczkowska B, Smurzynski P, Stanczyk A, Stolarz-Skrzypek K, Kawecka-Jaszcz K, Jastrzebski M, Podolec M, Kopec G, Stanula B, Kocowska M, Tylutki Z, Polak S. Model of the distribution of diastolic left ventricular posterior wall thickness in healthy adults and its impact on the behavior of a string of virtual cardiomyocytes. J Cardiovasc Transl Res 2014; 7:507-17. [PMID: 24676501 PMCID: PMC4098050 DOI: 10.1007/s12265-014-9558-4] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/28/2014] [Accepted: 03/05/2014] [Indexed: 11/28/2022]
Abstract
Correlation of the thickness of the left ventricular posterior wall (LVPWd) with various parameters, including age, gender, weight and height, was investigated in this study using regression models. Multicenter derived database comprised over 4,000 healthy individuals. The developed models were further utilized in the in vitro-in vivo (IVIV) translation of the drug cardiac safety data with use of the mathematical model of human cardiomyocytes operating at the virtual healthy population level. LVPWd was assumed to be equivalent to the length of one-dimensional string of virtual cardiomyocyte cells which was presented, as other physiological factors, to be a parameter influencing the simulated pseudo-ECG (pseudoelectrocardiogram), QTcF and ∆QTcF, both native and modified by exemplar drug (disopyramide) after I Kr current disruption. Simulation results support positive correlation between the LVPWd and QTcF/∆QTc. Developed models allow more detailed description of the virtual population and thus inter-individual variability influence on the drug cardiac safety.
Collapse
Affiliation(s)
- Kamil Fijorek
- Department of Statistics, Cracow University of Economics, Krakow, Poland
| | - Felix C. Tanner
- Cardiology, Cardiovascular Center, University Hospital Zurich, Zurich, Switzerland
| | - Barbara E. Stähli
- Cardiology, Cardiovascular Center, University Hospital Zurich, Zurich, Switzerland
| | - Grzegorz Gielerak
- Department of Cardiology and Internal Medicine, Military Institute of Medicine, Warsaw, Poland
| | - Pawel Krzesinski
- Department of Cardiology and Internal Medicine, Military Institute of Medicine, Warsaw, Poland
| | | | - Pawel Smurzynski
- Department of Cardiology and Internal Medicine, Military Institute of Medicine, Warsaw, Poland
| | - Adam Stanczyk
- Department of Cardiology and Internal Medicine, Military Institute of Medicine, Warsaw, Poland
| | - Katarzyna Stolarz-Skrzypek
- First Department of Cardiology, Interventional Electrocardiology and Hypertension, Jagiellonian University Medical College, Krakow, Poland
| | - Kalina Kawecka-Jaszcz
- First Department of Cardiology, Interventional Electrocardiology and Hypertension, Jagiellonian University Medical College, Krakow, Poland
| | - Marek Jastrzebski
- First Department of Cardiology, Interventional Electrocardiology and Hypertension, University Hospital, Krakow, Krakow, Poland
| | - Mateusz Podolec
- Department of Coronary Artery Disease, Jagiellonian University Medical College at the John Paul II Hospital, Krakow, Poland
| | - Grzegorz Kopec
- Department of Cardiac and Vascular Diseases, Jagiellonian University Medical College and Centre for Rare Cardiovascular Diseases at the John Paul II Hospital, Krakow, Poland
| | | | | | - Zofia Tylutki
- Unit of Pharmacoepidemiology and Pharmacoeconomics, Faculty of Pharmacy, Jagiellonian University Medical College, Krakow, Poland
| | - Sebastian Polak
- Unit of Pharmacoepidemiology and Pharmacoeconomics, Faculty of Pharmacy, Jagiellonian University Medical College, Krakow, Poland
| |
Collapse
|
50
|
Hill AP, Perrin MJ, Heide J, Campbell TJ, Mann SA, Vandenberg JI. Kinetics of Drug Interaction with the Kv11.1 Potassium Channel. Mol Pharmacol 2014; 85:769-76. [DOI: 10.1124/mol.114.091835] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
|