Journal of pharmacological and toxicological methods最新文献

{"title":"Optimization of computational hERG models for prediction and translation of cardiovascular risk in patients","authors":"Noelia Jacobo-Piqueras,&nbsp;Philipp Kügler,&nbsp;Georg Rast,&nbsp;Michael G. Leitner","doi":"10.1016/j.vascn.2026.108509","DOIUrl":"10.1016/j.vascn.2026.108509","url":null,"abstract":"<div><div>The human <em>ether-à-go-go</em> (hERG) channel plays an essential role in the repolarization of the cardiac action potential (AP) as it conducts the rapid component of the delayed rectifier potassium current. The inhibition of hERG channels by research compounds and drugs constitutes a relevant cardiovascular risk factor manifesting as AP broadening, early afterdepolarization phases, drug-induced QT interval prolongation and increased risk of Torsade de Pointes, a potentially lethal ventricular arrhythmia. Therefore, assessment of hERG blockade by new drug candidates is one of the mandatory tests to evaluate cardiac safety. To study the drug-induced proarrhythmic risk, a combination of both <em>in vitro</em> and <em><em>in silico</em></em> assays (in combination with pre-clinical in vivo ECG testing) has been proposed. However, the computer models currently available have important limitations that reduce its applicability: Hodking-Huxley models do not consider the transition kinetics among the different ion channel states, being inefficient to predict the cardiovascular risk of pharmacologically complex compounds. In turn, Markov formalisms cover transition kinetics and multiple channel conformations, but are both mathematically and technically demanding, and they are based on a set of assumptions that reduce their predictive power. Hence, the aim of this project is to improve available Markov hERG models by establishing optimized recording conditions that allow for replacement of set model assumptions by recorded parameters to predict more precisely pro-arrhythmic risk of compounds, independently of their pharmacological complexity. For that purpose, more informative and physiologically relevant electrophysiological protocols were developed and tested at controlled near-to-physiological temperature (35–36 °C) using the patch-clamp technique in HEK-293 cells overexpressing hERG channels. The most promising and optimized model consistently reproduced the maximal conductance, activation, deactivation, inactivation, and recovery parameters when a protocol consisting of a pre-pulse followed by a train of action potential waveforms was applied. The simulated traces were comparable to the experimentally recorded and the parameters were consistently fitted even after ten different simulations. However, although the model has been proved to fit the parameters under basal conditions, further pharmacological experiments using reference compounds reported to be hERG channel blockers, such as E-4031, are currently being performed to calibrate and validate the model.</div></div>","PeriodicalId":16767,"journal":{"name":"Journal of pharmacological and toxicological methods","volume":"140 ","pages":"Article 108509"},"PeriodicalIF":2.1,"publicationDate":"2026-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148730088","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Antisense oligonucleotides (ASOs) for gene therapy: A retrospective analysis of toxicology and safety pharmacology study designs and class effects","authors":"Simon Authier,&nbsp;Sabrina Quilez","doi":"10.1016/j.vascn.2026.108452","DOIUrl":"10.1016/j.vascn.2026.108452","url":null,"abstract":"<div><div>The rapidly evolving field of gene and nucleic acid therapy has presented exciting options for the treatment of many previously untreatable or poorly managed diseases and disorders. These therapies include several different families of molecular tools, such as antisense oligonucleotides (ASOs), designed to modulate gene and protein expression. In order to bring ASO-based therapies into a clinical setting, researchers must first assess their short- and long-term toxicity profiles in pre-clinical studies to establish parameters for safe clinical use. Here, a retrospective analysis of ASO-specific toxicology and safety pharmacology studies conducted across multiple test sites over a span of five (5) years are presented, with a focus on study designs and class effects. Emerging industry trends are highlighted with respect to dosing regimens, species selection, study duration, and study endpoints, and provide insights and recommendations on the design of future ASO therapy toxicology and safety pharmacology studies, including a commentary on biologically relevant dose ranges for these promising molecular tools. As well, ASO therapy -associated clinical signs, histopathological and clinical pathology findings are summarized to highlight class effects to consider during program design.</div></div>","PeriodicalId":16767,"journal":{"name":"Journal of pharmacological and toxicological methods","volume":"140 ","pages":"Article 108452"},"PeriodicalIF":2.1,"publicationDate":"2026-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148730512","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"In vitro neuronal electrical activity can predict in vivo acute neurotoxicity of ASO","authors":"Marie-Laure Craplet,&nbsp;Jean-Yves Thomas,&nbsp;Emilie Royère,&nbsp;Guillaume Das Dores,&nbsp;Gaëlle Hugon,&nbsp;Olivier Wattrelos,&nbsp;Nicolas Couvreur","doi":"10.1016/j.vascn.2026.108446","DOIUrl":"10.1016/j.vascn.2026.108446","url":null,"abstract":"<div><div>For ASOs (AntiSense Oligonucleotide) to be administrated via the IT route in patients, acute tolerability is evaluated <em>in vivo</em> in mice by behavioral side effects observation using Functional Observational Battery (FOB) performed 1 h following the single ICV (Intra Cerebro Ventricular) bolus injection.To support the 3R initiative and reduce the number of ASO tested <em>in vivo</em>, our objective was to develop an <em>in vitro</em> assay able to predict acute neurotoxicity observed <em>in vivo</em>.</div><div>To establish the vitro/vivo correlation, we measured effect of 35 ASOs on electrical activity of primary neurons using Micro Electrode Array (MEA) technology and compared it to 1 h FOB score. ASOs were incubated 30 min at 1, 3 and 10 μM. Electrical activity was recorded for 5 min at the end of each incubation period.</div><div>Among the &gt;50 parameters recorded, number of network bursts was the one showing the best correlation with tolerability score (FOB 1 h). The concentration of 3 μM displayed the best predictivity for safe ASOs and for very toxic ASOs <em>in vivo</em>. No false positive was observed at this concentration, so no ASO would be discarded in the <em>in vitro</em> assay while it is safe <em>in vivo</em>.</div><div><em>In vivo</em> acute toxicity of ASO showed a good correlation with desynchronization of the electrical activity of the neural network <em>in vitro</em>. This MEA <em>in vitro</em> assay performed before <em>in vivo</em> safety assessment would allow to divide the number of ASOs to be tested in animals by almost 2.</div></div>","PeriodicalId":16767,"journal":{"name":"Journal of pharmacological and toxicological methods","volume":"140 ","pages":"Article 108446"},"PeriodicalIF":2.1,"publicationDate":"2026-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148730516","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Development of an evaluation method for addictive compounds based on electrical activity of human iPS cell-derived dopaminergic neurons using MEA","authors":"Yuto Ishibashi,&nbsp;Nami Nagafuku,&nbsp;Noda Bumpei,&nbsp;Ikuro Suzuki","doi":"10.1016/j.vascn.2026.108443","DOIUrl":"10.1016/j.vascn.2026.108443","url":null,"abstract":"<div><div>Addiction is known to occur through the consumption of substances such as pharmaceuticals, illicit drugs, food, alcohol, and tobacco. These addictions can be viewed as drug addiction, resulting from the ingestion of chemical substances contained in them. Multiple neural networks, including the reward system, anti-reward/stress system, and central immune system in the brain, are believed to be involved in the onset of drug addiction. Although various compound evaluations using microelectrode array (MEA) as an in vitro testing methods to evaluate neural activities have been conducted, methods for assessing addiction have not been established. In this study, we aimed to develop an in vitro method for assessing the addiction of compounds, as an alternative to animal experiments, using human iPS cell-derived dopaminergic neurons with MEA measurements. MEA data before and after chronic exposure revealed specific changes in addictive compounds compared to non-addictive compounds, demonstrating the ability to estimate addiction of compound. Additionally, conducting gene expression analysis on cultured samples after the tests revealed changes in the expression levels of various receptors (nicotine, dopamine, GABA) due to chronic administration of addictive compounds, suggesting the potential interpretation of these expression changes as addiction-like responses in MEA measurements. The addiction assessment method using MEA measurements in human iPS cell-derived dopaminergic neurons conducted in this study proves effective in evaluating addiction of compounds on human neural networks.</div></div>","PeriodicalId":16767,"journal":{"name":"Journal of pharmacological and toxicological methods","volume":"140 ","pages":"Article 108443"},"PeriodicalIF":2.1,"publicationDate":"2026-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148730517","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Refinement of the respiratory impedance calibration process","authors":"Alexa Spencer,&nbsp;Jennifer Shaffer,&nbsp;Kevin Norton","doi":"10.1016/j.vascn.2026.108454","DOIUrl":"10.1016/j.vascn.2026.108454","url":null,"abstract":"<div><div>PhysioTel Digital L11R implants measure respiratory impedance on large animal safety pharmacology studies. While the raw impedance trace can be used to calculate respiratory rate without calibration, once calibrated, respiratory volume and volume changes can also be determined. The calibration process uses a known tidal volume for an animal to create a scaling factor, which when applied to the raw impedance signal provides a complete respiratory dataset.</div><div>There are multiple methods of calibration, most notably using a pneumotachometer to obtain the known volume from an animal. This process requires the use of a mask/helmet to measure each breath the animal takes and its corresponding tidal volume. While this method gives reliable volumes, there are a few limitations as it is labor intensive and intrusive on the animals due to requiring multiple days of mask/helmet acclimation and calibration. It is also important to remember that most large animal cardiovascular and respiratory safety pharmacology studies are conducted on freely moving animals with minimal disruption from staff. Therefore, the respiratory rates and tidal volume obtained from the mask/helmet during restraint periods are considerably different from those of non-restrained animals.</div><div>Keeping the 3R's in mind, namely refinement, we set out to determine if mask/helmet calibration could be replaced by a nominal calibration, eliminating the need for acclimation. Alexander et al. provide a formula [MV (L/min) = 0.608 x BW(kg)^0.852] for calculating the minute volume of an animal based on body weight. Since minute volume is a function of tidal volume x respiratory rate, the corresponding tidal volume can be calculated by dividing the MV by the individual's respiratory rate.</div><div>Several datasets from dogs and NHPs were analyzed and compared using both the mask/helmet calibration and the nominal calibration. The tidal volume trends from these collections were similar and test article and positive control changes were able to be identified regardless of calibration technique. In an attempt to refine the respiratory calibration process and expand upon the 3R's, the use of a nominal calibration has been confirmed as an acceptable method.</div></div>","PeriodicalId":16767,"journal":{"name":"Journal of pharmacological and toxicological methods","volume":"140 ","pages":"Article 108454"},"PeriodicalIF":2.1,"publicationDate":"2026-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148730518","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Simultaneous assessment of in vivo cardiovascular, respiratory and skeletal muscle indices in non-human primates model with cisatracurium and verapamil","authors":"Steve Roof,&nbsp;Yukie Ueyama,&nbsp;Robert Hamlin","doi":"10.1016/j.vascn.2026.108455","DOIUrl":"10.1016/j.vascn.2026.108455","url":null,"abstract":"<div><div>Simultaneous measurement of cardiovascular and respiratory systems has become increasingly popular, but their interdependent nature often obscures the individual contributions of each. In this study, we adapted existing rat and rabbit models to non-human primates to develop an anesthetized model enabling simultaneous assessment of both systems. This model aims to identify in vivo liabilities of active compounds. To validate system interdependence, we administered a known neuromuscular blocker (cisatracurium) and a negative inotrope/vasodilator (verapamil).</div><div>Six anesthetized and mechanically ventilated male and female rhesus macaques were acutely instrumented to simultaneously measure systemic and left ventricular hemodynamics (via catheterization) and respiratory/skeletal muscle function (via strain gauge) in a terminal setting. In four animals, measurements were taken before and during administration of cisatracurium (3 μg/kg/min for 30 min) and verapamil (12.5–100 μg/kg/min in escalating 15-min infusions). The remaining two animals were used to assess model stability over a 5-h period.</div><div>Cisatracurium elicited a precipitous decline in skeletal, diaphragmatic (respiratory), and peripheral limb (train-of-four) force until complete paralysis was achieved during the 20-min infusion. Function recovered over the next 40–60 min. Diaphragmatic force recovered the fastest, skeletal muscle recovered the slowest, and peripheral limb train-of-four in between. Heart rate and peak left ventricular pressures were unaffected by cisatracurium. Heart rate, peak left ventricular pressures, and diaphragmatic force reduced dose-dependently with verapamil. Complete cardiovascular collapse was achieved at 100 μg/kg/min. Skeletal muscle transiently increased during 25 and 50 μg/kg/min and subsequently fell during the highest dose. Peripheral limb train-of-four was unaffected by verapamil.</div><div>Taken together, these results and observations demonstrate an <em>in vivo</em> anesthetized and mechanically-ventilated non-human primates model is capable of detecting neuromuscular (diaphragmatic and skeletal) and cardiovascular alterations <em>in situ.</em> The non-human primate preparation was shown to be both stable and responsive to cardiovascular and neuromuscular changes triggered by either verapamil or cisatracurium.</div><div>Hence, the utility of this model could be extended to confirm liabilities of both cardiovascular and respiratory systems in a species that is more similar to humans.</div></div>","PeriodicalId":16767,"journal":{"name":"Journal of pharmacological and toxicological methods","volume":"140 ","pages":"Article 108455"},"PeriodicalIF":2.1,"publicationDate":"2026-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148730519","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Seizure threshold in spontaneously epileptic laboratory dogs","authors":"Magdalena K. Smyk,&nbsp;Henk van der Linde,&nbsp;Herman Borghys,&nbsp;Jan Serroyen,&nbsp;Gamal Abdel-Azim,&nbsp;Seon-ah Chong,&nbsp;David J. Gallacher","doi":"10.1016/j.vascn.2026.108436","DOIUrl":"10.1016/j.vascn.2026.108436","url":null,"abstract":"<div><div>Epilepsy is a multifactorial neurological disease characterized by recurrent seizures of different etiology and distinct clinical manifestation. In the general canine population, the prevalence of epilepsy is estimated up to 5%. In laboratory colonies, seizures either occur spontaneously or are evoked by a test substance or an experimental technique. Once reported, a dog is usually excluded from further safety testing due to concerns regarding altered threshold for CNS-related adverse effects. However, supporting data are scarce.</div><div>The present study aimed to estimate the seizure threshold in a group of Marshall Beagle dogs which had at least one spontaneous seizure and to also identify genomic regions associated with seizure activity in those animals, as well as dogs with induced seizures.</div><div>To estimate the seizure threshold, nine epileptic and nine healthy dogs were anesthetized and received an intravenous infusion of pentylenetetrazol (PTZ) at a rate of 1.5 mg/kg/min over a period of 40 min (total dose = 60 mg/kg) or until the occurrence of the electroencephalographic (EEG) seizure. The number of spikes in the EEG signal preceding seizures, seizure's threshold and duration were compared between groups. Genome-wide association study (GWAS) was applied to the spontaneous and induced seizures phenotypes; data were analyzed by univariate genome-wide efficient mixed-models fit (GEMMA).</div><div>Although the epileptic animals had on average more spikes in the EEG preceding seizure, surprisingly they required higher doses of PTZ and more time to elicit the first seizure. At 41 mg/kg all healthy dogs developed seizures, while in the epileptic group only 44%. Remarkably, one dog appeared resistant even to the maximal dose of PTZ.</div><div>GWAS revealed a good number of significant variants of spontaneous seizure phenotype with the strongest signal linked to chromosome 13: 2 receptor tyrosine kinase (RTK) genes, PDGFRA and KIT genes that were recently reported to be implicated in seizure activity.</div><div>The results suggest that the threshold for PTZ-induced seizures is elevated in spontaneously epileptic laboratory dogs. Further studies are needed to investigate responsible mechanisms. Genetic factors identified by GWAS may serve as a valuable tool in stratifying dogs for their susceptibility to idiopathic epilepsy.</div></div>","PeriodicalId":16767,"journal":{"name":"Journal of pharmacological and toxicological methods","volume":"140 ","pages":"Article 108436"},"PeriodicalIF":2.1,"publicationDate":"2026-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148730679","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A human iPSC-based platform for functional toxicity screening of CNS-targeted RNA therapeutics","authors":"Katerina Pitsa,&nbsp;Benoit Samson-Couterie,&nbsp;Jeroen Stein,&nbsp;Charles Leach,&nbsp;Silke Schwengberg,&nbsp;Shushant Jain","doi":"10.1016/j.vascn.2026.108440","DOIUrl":"10.1016/j.vascn.2026.108440","url":null,"abstract":"<div><div>Human induced pluripotent stem cell (iPSC)-derived neural co-cultures are increasingly recognized as powerful, physiologically relevant systems for modeling central nervous system (CNS) biology in vitro. In the context of RNA-based therapeutics, particularly antisense oligonucleotides (ASOs), CNS toxicity remains a major safety concern during drug development. To address this, we developed a human iPSC-based platform capable of high-throughput functional toxicity screening using calcium imaging as a readout for neuronal network activity.</div><div>The platform employs iPSC-derived neurons and astrocytes co-cultured in 384-well plates, enabling scalable assessment of calcium transient dynamics. Key metrics—calcium peak rate (0.15–0.25 Hz), amplitude (ΔF/F ≈ 1.5–2), and oscillation score (80–100%)—were stable under vehicle conditions with &lt;15% inter-well coefficient of variation, confirming assay reproducibility and robustness.</div><div>Seventy preclinical ASO candidates were screened, revealing three distinct toxicity profiles based on suppression of spontaneous calcium oscillations. Group 1 ASOs were classified as <strong>highly neurotoxic</strong>, causing &gt;60% suppression of oscillation scores with no recovery during a 15-min observation period. These candidates correlated with seizures and convulsions observed in vivo, consistent with data from Hagedorn et al. (Nucleic Acid Ther., 2022). Group 2 ASOs exhibited <strong>intermediate toxicity</strong>, with partial recovery (20–30%) of calcium activity and were associated with milder behavioral phenotypes. Group 3 ASOs maintained <strong>normal calcium activity</strong> even at high concentrations (up to 100 μM), indicating a lack of neurotoxicity.</div><div>Importantly, the in vitro calcium oscillation scores showed an ~80% correlation with CNS toxicity outcomes in rodent models, supporting the translational relevance of the assay. Furthermore, the platform was employed to guide ASO sequence modifications that mitigated neurotoxicity. One optimized ASO demonstrated a significant improvement in calcium oscillation score (~40% compared to baseline) without loss of intended therapeutic activity.</div><div>This study underscores the utility of human iPSC-derived neural co-cultures for early-stage, functional neurotoxicity screening of CNS-targeted RNA therapeutics. The platform offers a scalable, human-relevant alternative to animal testing, supporting safer and more efficient ASO drug development.</div></div>","PeriodicalId":16767,"journal":{"name":"Journal of pharmacological and toxicological methods","volume":"140 ","pages":"Article 108440"},"PeriodicalIF":2.1,"publicationDate":"2026-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148730683","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Relevance of human-based models to investigate the vascular toxicity induced by chemotherapy","authors":"Lukas Roubenne,&nbsp;Laura Francese,&nbsp;Richard Printemps,&nbsp;Stéphanie Guilbot,&nbsp;Bruno Le Grand","doi":"10.1016/j.vascn.2026.108515","DOIUrl":"10.1016/j.vascn.2026.108515","url":null,"abstract":"<div><div>Modern chemotherapies are often associated with cardiovascular toxicities—such as hypertension, thrombosis, heart failure, cardiomyopathy, and arrhythmias—that increase cardiovascular risk in cancer patients and may limit therapeutic options. However, predictive models remain scarce, partly due to interspecies differences. In this study, we investigated the vascular effects of doxorubicin (doxo), a widely used anthracycline with known cardiovascular toxicity, on rat and human arteries using ex vivo and in vitro approaches.</div><div>We evaluated acute doxo effects (30 min; 0.1, 1, 10 μM) on rat thoracic aorta and human subcutaneous arteries using organ bath and wire myography systems. We assessed basal tone, vasoconstriction responses to phenylephrine (PE) and serotonin (5-HT), and relaxation to acetylcholine (ACH) and sodium nitroprusside (SNP). Additionally, we developed an impedance-based in vitro assay to monitor vascular smooth muscle cell (SMC) contraction in response to vasoactive stimuli. SMCs from rat and human arteries were exposed to doxo, and responses to PE and 5-HT, as well as long-term effects on cell viability, were measured.</div><div>Doxo did not affect basal tone in either rat or human arteries. PE-induced vasoconstriction was unaffected in both species, but doxo (1 μM) enhanced 5-HT-induced contraction selectively in human arteries. Endothelium-dependent relaxation was impaired by doxo (1 and 10 μM) in both species, while endothelium-independent relaxation remained unchanged. In vitro, doxo did not alter acute SMC contraction to PE or 5-HT in rat cells, consistent with ex vivo findings. However, prolonged doxo exposure significantly decreased impedance signals in both rat and human SMCs, suggesting reduced cell viability.</div><div>Our study highlights species-specific vascular responses to doxorubicin, with notable differences in 5-HT-induced reactivity and endothelial function. These findings underline the importance of model selection in preclinical testing to better predict human vascular toxicity associated with anticancer therapies.</div></div>","PeriodicalId":16767,"journal":{"name":"Journal of pharmacological and toxicological methods","volume":"140 ","pages":"Article 108515"},"PeriodicalIF":2.1,"publicationDate":"2026-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148730715","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Categorizing TdP risk using hERG data obtained from automated patch-clamp using step-ramp hERG protocols and CiPA TMS values","authors":"Randall L. Rasmusson,&nbsp;Leigh Korbel,&nbsp;Mark W. Nowak,&nbsp;Kazuya Tsurudome,&nbsp;Lars Nilsson,&nbsp;Brian K. Panama,&nbsp;Shivani Acharya,&nbsp;Daniel R.P. Sauter,&nbsp;Glenna C.L. Bett","doi":"10.1016/j.vascn.2026.108507","DOIUrl":"10.1016/j.vascn.2026.108507","url":null,"abstract":"<div><div>The Comprehensive in-vitro Proarrhythmia Assay (CiPA) assesses drug effects on multiple ionic currents and a detailed drug-binding model of HERG to measure pro-arrhythmic risk (TMS value). Adoption of TMS for IND filings is hampered by difficult experimental protocols requiring manual patch-clamp data. Objectives: 1) Assess hERG drug block on currents from a step-ramp protocol using the Sophion QPatch Compact. 2) Determine drug TdP risk categorization from the TMS using CyberQ-qNet analysis software. 3) Determine best practices for data acquisition, current trace data processing, and quality control. hERG currents were recorded at 36 °C using a step-ramp protocol on the Sophion QPatch Compact platform using hERG-expressing CHO cells. Control currents were recorded until hERG current stabilization. Test currents were measured by perfusion with a single test drug concentration until steady-state block. Cells were then perfused with a reference compound (E-4031) resulting in complete block of hERG. Drugs tested were dofetilide, ondansetron, and moxifloxacin. Current traces underwent manual quality control, leak subtraction and reference current trace subtraction. Cytocybernetic's CyberQ-qNET analysis software calculated the qNet and TMS values. Step ramp TMS scores were compared to those obtained by the FDA using the Milnes protocol. CyberQ-qNet analysis software fitted raw HERG data to the CiPA three-state drug block model. The resulting analysis incorporated published values for other currents to obtain TMS. Similar qNET, TMS, and TdP risk categorization were similar with the Step-Ramp protocol and the Milnes protocol: dofetilide (0.0609 vs 0.0524), ondansetron (0.0675 vs 0.0625). Ondansetron was categorized as intermediate risk, but dofetilide was miscategorized as intermediate (although borderline and likely due to small N for low doses). For moxifloxacin (not a CiPA compound), TMS was 0.0552 and was categorized as high-risk TdP. Model fitting was highly sensitive to data quality. One important quality control subtraction of the reference current traces (100% hERG block) to remove non-hERG (i.e. native CHO) currents present in the step pulse. This suggests hERG currents from the Sophion QPatch at physiological temperature using the Step-Ramp could be a viable strategy for assessing arrhythmogenic potential of drugs using our CyberQ-qNet software in compliance with CiPA.</div></div>","PeriodicalId":16767,"journal":{"name":"Journal of pharmacological and toxicological methods","volume":"140 ","pages":"Article 108507"},"PeriodicalIF":2.1,"publicationDate":"2026-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148730085","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}