Frontiers in toxicology最新文献

The European Food Safety Authority (EFSA) carries out safety assessments of newly expressed proteins (NEPs) in genetically modified organisms (GMOs). Here, toxicity and allergenicity assessments are the cornerstone of NEP evaluation, ensuring that any potential health hazards are rigorously identified and characterised. Recent examples of EFSA's NEP safety assessments illustrate how novel methodologies, alongside established ones reconsidered from new perspectives, guide case-by-case decisions. These advances provide an opportunity to improve the robustness, proportionality, and scientific credibility of risk assessments. Moreover, it may alleviate the need for in vivo animal testing. Building on this development, EFSA aims to integrate new approach methodologies (NAMs) into risk assessment to provide a scientific basis for waiving in vivo testing, aligning its approach with the 3Rs principles (Replacement, Reduction, Refinement) and the European Commission's roadmap for phasing out animal testing. Overall, this shift reflects a broader transformation in EFSA's safety assessment of NEPs, characterised by openness to innovation, optimisation of existing methods, and ensuring preparedness for future risk assessment needs. The ultimate goal is to ensure the highest level of protection for human and animal health, while embracing scientific progress.

Scientific confidence frameworks (SCFs) are alternatives to traditional validation for new approach methodologies (NAMs). The SCFs adapted by the Interagency Coordinating Committee for the Validation of Alternative Methods (ICCVAM) and the American Chemistry Council (ACC) both address inference performance-the ability of NAMs to predict or inform the biological effect of interest. Inference performance is a distinct evaluation procedure in ACC's SCF but is blended into several steps of ICCVAM's SCF. Here, we first reproduce the previously derived human relevant potency threshold (HRPT) for the estrogen receptor alpha (ERα) agonism of Borgert et al. (2018) using guideline and guideline-like studies; we found that a HRPT of 1 to 10^-1 positively and consistently predicted clinical endometrial and endocervical effects. We next mapped inference performance to ICCVAM's SCF and found that it can be used as an effective initial screen prior to performing more detailed characterizations in their SCF. We first conclude that a HRPT for ERα agonism of 10^-2 to 10^-4 is a health-protective NAM based on an established mode of action that could potentially be used in early screening, much like the threshold of toxicological concern. We then conclude that inference performance is a core requirement for SCFs.

New Approach Methodologies (NAMs) hold great potential to fill data gaps for chemicals and modernisation of chemical risk assessment practices. Current toxicity testing is based on conventional approaches with high reliability on in-vivo studies, but with time, regulators are trying to move towards in-vitro and in silico tools enabling efficient risk assessment strategies. Herein, we discuss about different emerging techniques which are or can become a NAM including both in-vitro and in silico models with particular focus on reducing animal studies and improving decision-making for hazard and exposure assessment. We also discussed about the way to strengthen the regulatory and public confidence in different NAMs and automation of these approaches. Some of these NAMs can help in identifying biochemical mechanisms for toxicity, calculate the point of departure (PoD), develop adverse outcome pathways (AOP), translate risk to multiple species and quantify uncertainty from predictions for multiple chemicals. Scientists and regulators can work together to frame robust guidelines for the practical application of these tools and ensure reproducible results.

There is increasing evidence that pesticides act as endocrine disruptors, developmental toxicants, and reproductive toxicants. In this review, we describe several global challenges associated with pesticide production and use that put the health of human and wildlife populations at risk. These include: (1) the global production and use of pesticides is high, leading to increasing rates of release into the environment; (2) exposures to non-target species (including humans) are well documented, and pesticides often have adverse effects on these species; (3) pesticides, and especially those that are persistent organic pollutants, do not stay where they are used, contributing to ecosystem pollution far from their intended areas of application; (4) climate change can exacerbate the use of pesticides; and (5) social determinants of health (race/ethnicity, sex, and occupation) influence pesticide exposures and the adverse effects associated with these exposures. In 2009, the concept of planetary boundaries was introduced as a framework to evaluate how human actions impact earth systems. The planetary boundaries were based on a shared understanding that human activities have significant and sometimes irreversible effects on key aspects of environmental health. When considering the global impact of pesticides, these products can disrupt several planetary boundaries including biogeochemical cycles, biosphere integrity (e.g., measures of biodiversity), and the availability of clean freshwater, but the greatest challenge posed by pesticides is the "novel entities" boundary (i.e., the introduction of synthetic chemicals and materials into the environment). The planetary boundaries framework makes clear that failure to act against the most concerning chemicals, including pesticides, ultimately puts the survival of human populations at risk.

Introduction: High-throughput screening (HTS) in vitro testing can be a powerful tool for evaluating chemicals across an abundance of mechanistic, targeted assay systems. This study reviewed HTS in vitro data for the systematic evaluation of endpoints relevant to carcinogenesis. To these means, we focused on assay endpoints from the ToxCast/Tox21 HTS program that have been mapped to Key Characteristics of Carcinogens (KCCs) to help focus our review on the ∼750 assay endpoints that have been previously identified as potentially informative for evaluating modes of action relevant to carcinogenesis.

Methods: Data for ToxCast/Tox21 HTS assay endpoints were retrieved from the publicly accessible invitrodb v4.2 and reviewed for five chlorotriazine herbicides (atrazine, cyanazine, propazine, simazine, and terbuthylazine) to evaluate any indication of cancer-relevant bioactivity. More specifically, we present a workflow comprising the use of a focused assay endpoint inventory based on KCC attribution, integration of assay flags to identify robust bioactivity, and putting in vitro mechanistic insights into context with literature-based context for toxicokinetic considerations and in vivo evidence.

Results and discussion: There were common targets consistently identified as bioactive across the chemical class including induction of estrone levels and potential CAR/PXR activation. These findings were put in context by utilizing in vivo data and knowledge about atrazine to weigh the evidence. Though the ToxCast/Tox21 HTS mechanistic assays did not yield novel insights into chlorotriazine carcinogenicity, our workflow exemplifies how starting from mechanistic screening data and integrating apical endpoints can be conducted. By providing context to in vitro ToxCast/Tox21 data with toxicokinetics information and available in vivo study outcomes demonstrates how the HTS data and KCC framework can be applied to review a chemical class for carcinogenicity potential.

Introduction: Fish cell lines represent a powerful tool for studying the biology and toxicology of aquatic species in compliance with the 3Rs principles. In addition, they hold potential for more advanced biotechnological applications. However, fish cell cultures are mainly cultivated with fetal bovine serum. Therefore, in this study, we investigated the impact of serum reduction and the effects of six growth factors and cytokines on a sturgeon larval cell line (AOXla7y), which has been previously proven to be a valuable model for climate change and toxicology studies.

Methods: The serum reduction (from 10% to 5% and 2%) and the addition of two concentrations (10 and 50 ng/mL) of six growth factors and cytokines (FGF-2, IGF-1, LIF, IFN-γ, IL-13, and IL-15) to the 2% serum growth medium were evaluated over 6 days of cultivation. The morphology and cell density were determined using phasecontrast images after the experiment ended, while real-time label-free cell impedance (xCELLigence) was recorded throughout the cultivation period. Moreover, the end-point oxygen consumption in basal and uncoupled respiration conditions was analyzed with the Seahorse XF Cell Mito Stress Test Kit.

Results: The results demonstrated a general adaptation of the sturgeon cell line to a serum-reduced environment and the modulatory effects of growth factor and cytokine supplementation on cell growth and metabolism.

Discussion: These findings suggest that the sturgeon cell line has the potential to transition to a serumfree medium without major observed morphological modifications and with a limited reduction in proliferation. Its metabolism was differentially modulated by the signaling of growth factors and cytokines and exhibited a variable metabolic phenotype under mitochondrial stress. This study provides a characterization of the Atlantic sturgeon cell metabolism and offers a preliminary assessment for developing an animal-free and chemically defined medium.

Background: Drug poisoning is a growing public health concern, affecting both adult and pediatric populations. The COVID-19 pandemic has further influenced the incidence and patterns of these episodes. This study describes the clinical and epidemiological characteristics of drug poisoning episodes in adult and pediatric patients treated at a tertiary hospital in Spain between 2018 and 2024.

Materials and methods: This retrospective, observational, single-center study used data from the Spanish Minimum Basic Data Set of Hospital Discharges (CMBD-AH). All hospitalizations coded with a diagnosis of drug poisoning (ICD-10-ES: T36-T50) were included. Variables analyzed included demographics, type of admission, drug class involved, intentionality, length of stay, ICU admission and duration, and clinical outcomes.

Results: A total of 2,989 episodes with at least one drug poisoning code were identified in 2,481 patients (85.7% adults; 14.3% pediatric). The median age was 55 years in adults and 14 years in pediatric patients. Females predominated in both groups. Self-poisoning was the most frequent intentionality (52.4% in adults; 54.7% in pediatric patients), while accidental poisonings were more common in pediatric patients under 12 and adults over 60. Benzodiazepines were the most frequently involved drug-class across all age groups; in pediatric self-poisoning, paracetamol was most commonly implicated. ICU admission was required in 9.6% of pediatric and 9.2% of adult episodes. Mortality was reported in 3.3% of adult and 0.5% of pediatric episodes. Additionally, 12.5% of patients experienced recurrent episodes. A significant post-COVID increase in poisoning episodes was observed (p < 0.001).

Conclusion: Although drug poisoning represented only 1.7% of all hospital discharges, it posed a substantial burden due to its frequency, recurrence, and ICU requirements. The CMBD-AH is a valuable tool for characterizing drug-related hospitalizations across age groups. Strengthened toxicovigilance, targeted prevention strategies, and early mental health interventions are essential to reduce its impact on healthcare systems.

The widespread use of fetal bovine serum (FBS) and other animal-derived reagents in cell culture raises ethical concerns and scientific limitations, including batch variability and undefined composition. To address these challenges and promote the adoption of xeno-free, human-relevant methods, we developed a graduate-level laboratory course based on animal-free workflows. The curriculum covers key molecular and cell biology techniques: HeLa cell culture and passaging, transfection, RNA interference (RNAi), quantitative RT-PCR (qRT-PCR), dual-luciferase assays, and Western blotting, using reagents selected to exclude animal-derived components. A chemically defined medium (CDM) was optimized for robust HeLa cell growth in the absence of FBS, and recombinant TrypLE was implemented as a substitute for porcine trypsin. Validated non-animal-derived antibodies are also introduced. The course has been successfully piloted and provides a scalable, ethical framework for modern bioscience education. A detailed, open-access protocol enables replication and dissemination. This initiative equips students with practical skills and educational foundation in animal-free methodologies, supporting a shift toward reproducible and ethically responsible biomedical research.

Background: Acetaldehyde and methylglyoxal are structurally related aldehydes produced by thermal degradation of the electronic cigarette (EC) solvents, propylene glycol and glycerin. Despite their presence in EC aerosols, the biological effects of these aldehydes when inhaled during vaping are largely unknown.

Methods: Three-dimensional (3D) human bronchial epithelial tissues (EpiAirway™) were exposed at the air liquid interface (ALI) to aerosols containing acetaldehyde or methylglyoxal at concentrations relevant to human vaping. PBS-exposed tissues served as controls. Comparative proteomic analyses were performed to assess global alterations in protein expression. Based on proteomics data, concentration-response experiments were conducted using BEAS-2B bronchial epithelial cells to evaluate reactive oxygen species, mitochondrial function, and cytoskeletal integrity.

Results: ALI exposure to acetaldehyde or methylglyoxal resulted in 79 and 76 differentially expressed proteins (DEPs), respectively, with 51 overlapping proteins exhibiting similar fold change directionality. Ingenuity Pathway Analysis (IPA) Toxicity Lists identified key affected pathways, including mitochondrial dysfunction, fatty acid metabolism, G2/M DNA damage checkpoint regulation, and mitochondrial biogenesis. Gene Ontology (GO) ontology analysis revealed substantial overlap in affected biological processes and cellular components. Findings were further supported and expanded in BEAS-2B cell concentration-response assays, which confirmed mitochondrial impairment, elevated ROS levels, and disrupted cytoskeletal organization. Notably, TRPM8 inhibition attenuated methylglyoxal-induced mitochondrial dysfunction (MTT assay), while both TRPM8 and TRPA1 inhibition partially rescued actin depolymerization.

Conclusion: Brief ALI exposure of EpiAirway™ tissues to vaping-relevant concentrations of acetaldehyde or methylglyoxal altered the bronchial epithelial proteome. Complementary concentration-response experiments with submerged BEAS-2B cells confirmed and extended the proteomics data. While both aldehydes exhibited similar proteomic and functional impacts, methylglyoxal was effective at substantially lower concentrations in all assays with some effects partially mediated via TRPA1 and TRPM8 channels.

With the increasing prevalence of alcohol-related diseases, expanding our understanding of the toxic effects of excessive alcohol consumption is critical for prevention and treatment of metabolic and inflammatory pathology. This review summarizes current knowledge on the metabolic dysfunction and inflammation caused by alcohol and their impact on the pathogenesis of alcohol-related liver disease (ALD), type 2 diabetes, cardiovascular disease, and obesity, and neurological damage. It highlights recent evidence that alcohol induces a cascade of reactive oxygen species (ROS)-mediated lipid peroxidation and nicotinamide adenine dinucleotide (NAD⁺) depletion, triggering mitochondrial dysfunction and metabolic imbalances in the liver, heart, pancreas, and brain. By integrating these mechanistic insights with emerging data on how disrupted lipid and glucose metabolism amplify immune dysregulation, the review underscores the interplay between metabolic and inflammatory pathways in exacerbating tissue injury across these organs. A deep understanding of these metabolic and inflammatory disruptions is therefore essential for developing novel therapeutic strategies, including metabolic and nutritional interventions, aimed at mitigating the health risks of excessive alcohol consumption.