Archives of Toxicology最新文献

{"title":"Elevated water temperatures enhance 2,4,6-trinitrotoluene induced stress response of carbonyl reductase in blue mussels (Mytilus edulis): Another environmental impact of climate change?","authors":"Jacqueline Lindemeyer, Romina Marietta Schuster, Lili Hartmann, Lillian Tabea Hannah Bünning, Matthias Brenner, Edmund Maser, Jennifer Susanne Strehse","doi":"10.1007/s00204-026-04520-x","DOIUrl":"https://doi.org/10.1007/s00204-026-04520-x","url":null,"abstract":"<p><p>Toxic explosives leaking from submerged munitions appear as an emerging marine pollutant in recent years. The nitroaromatic compound 2,4,6-trinitrotoluene (TNT) is of particular interest in this context. TNT poses a threat to marine environments and organisms. Previous studies showed that TNT and its metabolites are incorporated in mussel tissue thereby causing adverse effects through cellular oxidative stress. Recently, the impact of TNT on mRNA expression of the enzyme carbonyl reductase (CR) in blue mussels was discovered. This enzyme plays a key part in the cellular antioxidative system. A factor that should be taken into account is the increase in water temperature caused by anthropogenic climate change. To investigate potential synergistic effects of TNT in combination with elevated water temperatures on CR expression, blue mussels were exposed to concentrations of 0.1 µg/L, 50 µg/L, and 500 µg/L TNT and water temperatures of 11 °C, 15 °C and 18 °C, respectively, in the present study. Semiquantitative PCR analysis of CR mRNA expression in different tissues confirmed that TNT leads to increased mRNA expression levels, especially in gill tissue even at lower concentrations than tested in previous studies. Furthermore, varying water temperatures apparently influenced CR gene expression. Our study suggests a higher vulnerability to xenobiotic-induced oxidative stress in case of simultaneous presence of pollution from munitions and elevated water temperature. Our findings also underline the importance of molecular biomarkers like CR as a method for assessment of the impact of environmental stressors on the marine ecosphere.</p>","PeriodicalId":8329,"journal":{"name":"Archives of Toxicology","volume":" ","pages":""},"PeriodicalIF":10.9,"publicationDate":"2026-08-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148811871","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A human PBMC-based new approach method reveals PFAS-driven T-cell proliferation and immune dysregulation.","authors":"Allison Loan, Lauren M Bradford, Andrée Nunnikhoven, Gong Zhang, Emily Dupuis, Eunnara Cho, Matthew J Meier, Rocio Aranda-Rodriguez, Azam Tayabali, Kristin M Eccles, David Prescott","doi":"10.1007/s00204-026-04525-6","DOIUrl":"https://doi.org/10.1007/s00204-026-04525-6","url":null,"abstract":"<p><p>Immunotoxicity has emerged as a key health concern for per- and polyfluoroalkyl substances (PFAS), with animal studies showing reduced T-dependent antibody responses (TDAR) and epidemiological studies reporting decreased vaccine antibody titres. Notably, immunotoxicity is considered one of the most sensitive endpoints for PFAS exposure and has been used to inform regulatory guidance and health-based values. Given that more than 14,000 PFAS exist and are highly environmentally persistent, evaluating the immunotoxicity of individual compounds is critical but impractical, highlighting the need for efficient, human-relevant test systems that provide mechanistically informative, immune-relevant endpoints. Here, we assessed immunomodulatory effects of six PFAS analogues using an in vitro human peripheral blood mononuclear cell (PBMC) model. Two immune stimuli were applied, including lipopolysaccharide (LPS) to trigger innate responses and phytohemagglutinin (PHA) to simulate T-cell-mediated adaptive immune activation. Critically, several PFAS analogues enhanced T-cell proliferation following PHA activation, while a non-inclusive but overlapping subset of analogues suppressed cytokine secretion in response to PHA and LPS. Transcriptomic analyses indicate reduced B-cell identity and immunoglobulin gene expression alongside increased expression of genes associated with T-cell activation and proliferation. These findings implicate a dysregulated coordination between T- and B-cell responses as a potential mechanism underlying PFAS-associated immunotoxicity. Overall, the human PBMC model demonstrated that it is a cost-effective and ethical method for identifying and characterizing key events (KEs) in the adverse outcome pathway (AOP) for PFAS-induced immunotoxicity and has the potential to be refined and incorporated into a robust new approach method (NAM) to assess the next generation of commercial PFAS.</p>","PeriodicalId":8329,"journal":{"name":"Archives of Toxicology","volume":" ","pages":""},"PeriodicalIF":10.9,"publicationDate":"2026-08-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148811881","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The role of toll-like receptors in tributyltin-, dibutyltin-, and pentachlorophenol-induced stimulation of tumor necrosis factor-alpha (TNFα) production in human immune cells.","authors":"Latoya M Daniel, Aleshia Seaton-Terry, Ellie Bray, Meaghan Lewis, Zinia Hunter, Sophia Fisher, Brian Townsend, Margaret M Whalen","doi":"10.1007/s00204-026-04522-9","DOIUrl":"10.1007/s00204-026-04522-9","url":null,"abstract":"<p><p>Tributyltin (TBT), Dibutyltin (DBT), and Pentachlorophenol (PCP) are persistent environmental contaminants that increase immune-cell production of pro-inflammatory cytokines and thus have the capacity to cause chronic inflammation and its associated pathologies such as cancer, cardiovascular disorders, and autoimmune conditions. TBT has been detected in human blood at concentrations up to 260 nM, DBT up to 0.3 µM, and PCP between 0.15 and 5 µM. Tumor necrosis factor-alpha (TNF-α) is a pro-inflammatory cytokine produced by immune cells in response to pathogen- or damage-associated molecular patterns (PAMPs/DAMPs) via Toll-like receptors (TLRs). Dysregulated TNF-α production contributes to chronic inflammatory pathology. Previous studies have shown that TBT, DBT, and PCP increase pro-inflammatory cytokine production by immune cells and that these increases depend on mitogen-activated protein kinases (MAPKs), which are downstream components of TLR activation. The current study indicates that TLR4 plays a role in TBT-, DBT-, and PCP-induced production of TNF-α. Additionally, TBT-induced TNF-α production was, at least in part, dependent on TLR2, DBT-induced TNF-α production on TLR1/2 and PCP-induced TNF-α production on TLR3 and TLR8. Blocking the initial component of TLR1/2, TLR2, TLR4, and TLR8 signaling, MyD88, led to very significant blockade of TBT- and PCP-induced TNF-α production. These findings provide additional understanding as to how compounds that are persistent pollutants activate production of a crucial regulator of inflammation, TNF-α, potentially contributing to chronic inflammation and its associated diseases.</p>","PeriodicalId":8329,"journal":{"name":"Archives of Toxicology","volume":" ","pages":""},"PeriodicalIF":10.9,"publicationDate":"2026-08-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13543161/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148811907","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"PFAS: challenges and scientific perspectives in human health risk assessment.","authors":"Janine Kowalczyk, Klaus Abraham, Christina August, Runa S Boeddinghaus, James C Y Chan, Alexander Eckhardt, Tony Fletcher, Finnian Freeling, Bernd Göckener, Thorhallur I Halldórsson, Dorte Herzke, Ron L A P Hoogenboom, Kristina Jakobsson, Christian Jung, Federica Madia, Bernhard Monien, Jorge Numata, Louise Ramhøj, Greet Schoeters, Katharina Sommerkorn, Xenia Trier, Periklis Tsiros, Christian Unkelbach, Stefan P J van Leeuwen, Thorsten Buhrke","doi":"10.1007/s00204-026-04523-8","DOIUrl":"https://doi.org/10.1007/s00204-026-04523-8","url":null,"abstract":"<p><p>To review recent advances in research on per- and polyfluoroalkyl substances (PFAS) and outline priority steps for risk assessment in consumer health protection, the German Federal Institute for Risk Assessment (BfR) organized the 'International PFAS Conference' in Berlin in October 2025. Building on the European Food Safety Authority's (EFSA) opinion in 2020, global research activities on PFAS have intensified. The conference was attended by 200 participants from 18 countries and covered topics such as analytical methods, human exposure, toxicokinetics, toxicity, and future perspectives. Given that there are more than 21,000 different PFAS in use, discussions highlighted the need for further data collection and a basis for prioritizing substances. Robust exposure assessment requires improved analytical methods combined with newly developed predictive tools to quantify, identify, and make better use of non-target data. Hazard characterization may benefit from the combined use of classic experimental data sets, epidemiological data, and new approach methodologies (NAMs) data. The participants emphasized the continuous need for refined data and proposed a systematic consolidation of global data on shared data platforms, accompanied by corresponding guidelines for data usage. In the final panel discussion, effective risk communication was identified as a critical challenge, necessitating clear and consistent messaging for the public and policymakers. The conference concluded with five key recommendations for future health risk assessments: prioritizing PFAS; improving analytical methods; promoting generation of robust data and data gap filling; promoting open science, including the development of shared data infrastructure and cross-institutional knowledge exchange; and strengthening risk communication. These recommendations aim to support transparent, evidence-based and effective PFAS consumer health risk management in the decades ahead.</p>","PeriodicalId":8329,"journal":{"name":"Archives of Toxicology","volume":" ","pages":""},"PeriodicalIF":10.9,"publicationDate":"2026-08-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148811936","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The NAMs conundrum in the current regulatory risk assessment: progress without clarity?","authors":"Qasim Chaudhry, Vera Rogiers, Pieter-Jan Coenraads, Emilio Benfenati, Ulrike Bernauer, Corrado Lodovico Galli, Eirini Panteri, Tamara Vanhaecke","doi":"10.1007/s00204-026-04529-2","DOIUrl":"https://doi.org/10.1007/s00204-026-04529-2","url":null,"abstract":"<p><p>The gradual build up of political and societal pressures over the past few decades has led to a considerable momentum for moving away from animal testing for chemical risk assessments towards alternative non-animal methods (NAMs). However, despite a lot of progress made in this field, the true potential of NAMs to replace animal tests has yet to be realised. This is because of the structure and practice of the current risk assessment paradigm, and the uncertainties and lack of standardised frameworks for 'weighting' NAMs data when integrating to the overall weight of evidence for use in risk assessment. This Editorial highlights the key issues to focus attention in regard to the mismatch between general expectations and true ranking of the data generated by NAMs for use in regulatory risk assessment of chemicals.</p>","PeriodicalId":8329,"journal":{"name":"Archives of Toxicology","volume":" ","pages":""},"PeriodicalIF":10.9,"publicationDate":"2026-08-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148811932","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Research progress on the toxicological characteristics and biodegradation of deoxynivalenol and its derivatives.","authors":"Jingjing Zhao, Yukai Lin, Yanwei Li, Meinan Chang, Lei Wang, Xiaojing Xia, Yanzhao Xu, Bo Wen, Ruibiao Wang, Ke Ding","doi":"10.1007/s00204-026-04524-7","DOIUrl":"10.1007/s00204-026-04524-7","url":null,"abstract":"<p><p>Deoxynivalenol (DON) and its derivatives are widely distributed contaminants that seriously threaten food security and animal husbandry production. Biodegradation has become a core research direction for detoxification owing to its high efficiency and specificity. Although numerous studies have reported the toxicity, metabolism and degradation of DON and its derivatives, systematic reviews that integrate toxic mechanisms, species differences, degrading strains and key enzymes remain scarce. This paper comprehensively reviews the toxicological mechanisms and toxicokinetic characteristics of DON and its typical derivatives, and illustrates the physiological basis for species sensitivity differences. It mainly summarizes various degrading bacteria, fungi and core enzymatic catalytic pathways, and analyzes the potential risks of masked mycotoxins as well as the application bottlenecks of current biological detoxification technologies. Future research directions are also prospected. This review can serve as a reference for the research, development and industrial application of efficient and safe microbial detoxification strategies.</p>","PeriodicalId":8329,"journal":{"name":"Archives of Toxicology","volume":" ","pages":""},"PeriodicalIF":10.9,"publicationDate":"2026-08-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148787599","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Toxic in vitro effects of flavoured-air inhalers containing essential oils in differentiated human nasal epithelial cells at air-liquid interface.","authors":"Alexander N Larcombe, E E Catchpole, P Hopper, S Stanley, A Kicic, K R Landwehr","doi":"10.1007/s00204-026-04521-w","DOIUrl":"10.1007/s00204-026-04521-w","url":null,"abstract":"<p><p>Flavoured-air inhalers containing essential oils are marketed as safe, natural alternatives to smoking and vaping, yet their potential respiratory toxicity remains effectively unexamined. Manufacturers claim safety based on \"100% natural\" ingredients, despite evidence that essential oil inhalation can cause adverse respiratory effects. Our objective was to assess the in vitro toxicity of six commercially available flavoured-air products on human nasal airway epithelial cells. Differentiated air-liquid interface cultures of primary nasal airway epithelial cells from eight healthy adults were exposed for one hour to air (control) or flavoured air from three devices (Füm, Lio, Cigtrus; two flavours each) generated by drawing air through essential oil-infused cores at a continuous airflow of 1 L/min for one hour into an 1000 mL exposure chamber. Outcomes included transepithelial electrical resistance, cytotoxicity, protein release, cytokine/chemokine profiling and histological assessment. Chemical analysis characterised the chemical composition of device cores and identified 29 compounds across the six products, including the possible carcinogen pulegone and cytotoxic cinnamaldehyde. Five of six flavours significantly reduced transepithelial electrical resistance indicating compromised epithelial barrier integrity. Mediator responses were compartment-specific: apical surfaces showed predominantly pro-inflammatory profiles while basal release was broadly suppressed. Histological analysis revealed reduced cilia coverage, fewer mucus-producing cells, and decreased epithelial thickness across multiple treatments. This study shows that a single one-hour exposure to flavoured-air vapour led to epithelial barrier dysfunction, immune dysregulation, and structural damage in healthy human nasal airway epithelial cells, contradicting manufacturer safety claims. Rigorous toxicological evaluation of these products is urgently needed.</p>","PeriodicalId":8329,"journal":{"name":"Archives of Toxicology","volume":" ","pages":""},"PeriodicalIF":10.9,"publicationDate":"2026-08-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148719951","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Oxidative stress and inflammation in neurodegenerative disorders","authors":"Klaudia Jomova,&nbsp;Suliman Y. Alomar,&nbsp;Richard Valko,&nbsp;Eugenie Nepovimova,&nbsp;Kamil Kuca,&nbsp;Marian Valko","doi":"10.1007/s00204-026-04518-5","DOIUrl":"10.1007/s00204-026-04518-5","url":null,"abstract":"&lt;div&gt;&lt;p&gt;The brain’s consumption of approximately 20% of the body’s oxygen contributes to oxidative stress, a significant pathological factor in neurodegenerative diseases such as Alzheimer’s disease, Parkinson’s disease, Huntington’s disease, and amyotrophic lateral sclerosis. This oxidative stress, linked to low levels of antioxidant enzymes, drives neuronal death by facilitating membrane peroxidation of fatty acids, proteins, and DNA. Alzheimer’s disease is characterized by amyloid-beta (Aβ) plaque accumulation and hyperphosphorylated tau aggregates, both of which interact with mitochondria to generate reactive oxygen species (ROS). Aβ peptides bind metals such as iron and copper, catalyzing the formation of damaging hydroxyl radicals. Peripheral markers of oxidative damage, such as elevated malondialdehyde and protein carbonyls, are correlated with these processes in affected patients. In Parkinson’s disease, the loss of dopaminergic neurons in the substantia nigra is associated with pathological iron accumulation and mitochondrial complex I dysfunction, which are worsened by misfolded α-synuclein and mutations in antioxidant genes such as PINK1 and Parkin. The autooxidation of dopamine also drives oxidative stress through the generation of hydrogen peroxide and reactive quinones. Huntington’s disease involves the degeneration of medium spiny neurons in the striatum due to a polyglutamine repeat expansion in the huntingtin gene, which disrupts mitochondrial function and downregulates antioxidants, leading to excitotoxicity and ROS spikes. Amyotrophic lateral sclerosis primarily affects motor neurons due to the mutations in SOD1, which result in the production of aggregates that impair mitochondria and generate reactive nitrogen species (RNS), such as peroxynitrite. Mitigating oxidative stress in neurodegenerative disorders presents a considerable translational challenge. While low-molecular-weight antioxidant therapies for neurodegenerative disorders have shown promising results in preclinical and animal studies because they mitigate oxidative stress, their clinical efficacy is hampered by low bioavailability and difficulty in penetrating the blood‒brain barrier. To overcome these limitations, current medical research is focused on alternative delivery systems. Innovations such as nanoparticle-based drug delivery are being actively studied to help transport low-molecular-weight antioxidants across the blood‒brain barrier more safely and effectively. Several promising epidemiological trials linked high dietary intake of vitamins C and E to a reduced risk of Parkinson’s disease, and plant-derived antioxidants such as polyphenols were explored for their ability to combat neuroinflammation and reduce cognitive decline. Refined oxidative stress-suppressing strategies involve the (ii) application of mitochondrial-targeted agents to preserve ATP production; (ii) boosting the Nrf2 pathway may trigger a cascade of detoxifying enzymes; (iii) supplementa","PeriodicalId":8329,"journal":{"name":"Archives of Toxicology","volume":"100 10","pages":"4367 - 4445"},"PeriodicalIF":10.9,"publicationDate":"2026-08-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s00204-026-04518-5.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148711188","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Cardiosim-Tox: an interpretable multitask deep learning QSAR platform with multimodal feature fusion for predicting hERG, Cav1.2, and Nav1.5 blockade risk and potency.","authors":"Fauzan Syarif Nursyafi, Byunggyu Kang, Junhyeok Eom, Rahmafatin Nurul Izza, Abdul Latif Fauzan, Nadilla Hafani Putri, Ulfa Latifa Hanum, Yossi Olivia, Sanjida Afrin Rose, Ki Moo Lim","doi":"10.1007/s00204-026-04519-4","DOIUrl":"https://doi.org/10.1007/s00204-026-04519-4","url":null,"abstract":"<p><p>Drug-induced cardiotoxicity, mainly driven by cardiac ion-channel blockade, remains a leading cause of drug attrition and post-market withdrawal, highlighting the need for reliable early-stage screening tools. Existing computational methods, including QSAR models, largely focus on single ion channels, limiting their ability to assess multi-channel safety profiles. To address this gap, we developed Cardiosim-Tox, a modular multi-modal deep learning platform to simultaneously predicts blockade risk (binary classification) and potency (pIC₅₀) for hERG, Cav1.2, and Nav1.5. The framework integrates topological fingerprints, Mordred 2D/3D descriptors, and molecular graph encodings under both single-task (STL) and multi-task learning (MTL) configurations. Developed on 31,816 curated unique compounds, model performance was evaluated on three Tanimoto similarity-stratified external validation sets, with domain-shift metrics and applicability domain analyses supporting robustness. MTL models consistently outperformed STL, while the full modality combination (FP + MD + Graph) achieved AUCs of 0.93-0.98 for Cav1.2, 0.88-0.96 for Nav1.5, and 0.79-0.95 for hERG across validation sets. Regression tasks similarly favored MTL (R² = 0.94), with multimodal configurations outperforming single-modality baselines. Further comparisons with classical machine learning models and previously developed cardiotoxicity models demonstrated the superiority of Cardiosim-Tox across all endpoints. SHAP analysis confirmed that feature-activity relationships, both at global and mechanistic levels, align with known ion-channel pharmacophores, enhancing interpretability beyond predictive accuracy. Overall, Cardiosim-Tox provides a reliable and interpretable platform for integrated multi-channel cardiac safety assessment, supporting early-stage cardiotoxicity screening in drug development in line with the CiPA paradigm. The Cardiosim-Tox web server is accessible at https://metaheart.kr/login .</p>","PeriodicalId":8329,"journal":{"name":"Archives of Toxicology","volume":" ","pages":""},"PeriodicalIF":10.9,"publicationDate":"2026-08-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148711258","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Challenging the specificity of chlorzoxazone and 4-nitrophenol as marker substrates for CYP2E1 activity in Supersomes™.","authors":"Anna Hellmann, Ann-Kathrin Lenich, Stephanie Ruez, Jörg Fahrer, Jasmin Lott, Michelle Schaefer","doi":"10.1007/s00204-026-04515-8","DOIUrl":"https://doi.org/10.1007/s00204-026-04515-8","url":null,"abstract":"<p><p>Cytochrome P450 2E1 (CYP2E1) plays a pivotal role in the metabolism and detoxification of low molecular-weight xenobiotics, as well as in their bioactivation into toxic and DNA-reactive intermediates. Prominent examples include drugs and chemicals like acetaminophen and N-nitrosamines. Chlorzoxazone and 4-nitrophenol are widely used as probe substrates to assess CYP2E1 activity, however, their specificity remains controversial. This study aimed to reevaluate the selectivity of chlorzoxazone and 4-nitrophenol toward CYP2E1 using recombinant Supersomes™ expressing individual human CYP isoforms. Incubations were performed with chlorzoxazone and 4-nitrophenol at 100 and 500 µM, followed by quantification of 6-hydroxychlorzoxazone and 4-nitrocatechol via UPLC-MS/MS. Chlorzoxazone turnover was detected across nearly all major liver CYP isoforms, with CYP1A1 showing the highest contribution (39%), followed by CYP2D6 (14%), CYP1A2 (10%), and CYP2E1 (10%). Similarly, 4-nitrophenol hydroxylation was not limited to CYP2E1, with significant contributions from CYP1A2 (20%), CYP2A6 (19%), and CYP2D6 (16%), while CYP2E1 accounted for 26% of total activity. In conclusion, our results underscore the limited selectivity of chlorzoxazone and 4-nitrophenol and highlight the need for more specific substrates for accurate CYP2E1 enzyme characterization.</p>","PeriodicalId":8329,"journal":{"name":"Archives of Toxicology","volume":" ","pages":""},"PeriodicalIF":10.9,"publicationDate":"2026-08-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148668137","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}