Frontiers in toxicology最新文献

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.

Macrophages, essential components of the innate immune system, are considered to be involved in the regulation of Leydig cell steroidogenesis, though by mechanisms that remain uncertain. Mono-(2-ethylhexyl) phthalate (MEHP), the active metabolite of di-(2-ethylhexyl) phthalate (DEHP), has been shown to affect testosterone production directly via its effects on Leydig cells, but also has been implicated in immune system modulation. These observations raise the possibility that MEHP might affect male steroidogenesis both by its direct effects on Leydig cells and perhaps also indirectly through its effects on macrophages. As yet, however, MEHP effects on macrophages and the potential relationship between macrophage response and Leydig cell steroidogenic function are poorly understood. Using in vitro methodology, we investigated the effects of MEHP on macrophage function and of downstream effects of changes in macrophage function on Leydig cell steroidogenesis. Mouse macrophage RAW 264.7 cells were cultured with MEHP (0-300 µM) for 24 h. Significant dose-dependent changes were seen in these cells in response to MEHP exposure, including increased cell size and granularity, increased mitochondrial content and membrane potential, decreased ATP production and oxygen consumption, and elevated intracellular and mitochondrial-derived oxidative stress. These changes suggested a pro-inflammatory response of the RAW 264.7 cells to MEHP. MEHP exposure activated the p38 MAPK pathway linking oxidative stress to inflammatory signaling and induced a dose-dependent increase in TNF-α secretion. In vitro exposure of MA-10 Leydig cells to TNF-α was found to inhibit steroid (progesterone) production by these cells. The observations, taken together, that TNF-α was secreted by MEHP-activated macrophages and that exposure to TNF-α can inhibit LH-stimulated steroid (progesterone) production by MA-10 Leydig cells suggest the possibility of the involvement of an immune-mediated mechanism resulting from MEHP exposure on impaired Leydig cell steroid production.

Per- and polyfluoroalkyl substances (PFAS) are widespread anthropogenic contaminants known to the scientific community for their persistence and toxicity. Our research aims to evaluate the effect of chronic environmental exposure to PFAS on the antioxidant system of Squalius cephalus. In particular, to better understand how various components of the antioxidant system act together to counteract the adverse effects of PFAS, in the present study we evaluate the gene expression and enzymatic activity of two selenium-dependent glutathione peroxidases (namely GPx-1 and GPx-4) and the catalase, in the two major organs involved in the accumulation and detoxification from pollutants, including PFAS, i.e. liver and caudal kidney. Fish were sampled from four sites in the Veneto region with different concentrations of total dissolved PFAS. To better assess the acclimatisation to the environment, the morphological characteristics of the fish were also examined, as well as the development of organs, through the calculation of some somatic indices. Lipid accumulation was demonstrated histologically in both the liver and caudal kidney, which likely occurs to attenuate the high reactivity of PFAS toward protein content in these organs. The results demonstrate how Squalius cephalus can survive chronic PFAS exposure through cellular and systemic physiological responses.

The increasing misuse of benzodiazepines (BZDs) in drug-facilitated crimes (DFCs) has become a serious concern for forensic experts, healthcare professionals, and legal authorities. These drugs, which are commonly prescribed for anxiety and sleep disorders, are also used to commit crimes such as sexual assault and robbery. Their sedative and memory-blocking effects render them particularly dangerous. One of the biggest challenges is that BZDs are rapidly broken down in the body, limiting the time available for detection. This creates major problems in forensic investigations and reduces the chance of holding offenders accountable for their actions. In addition, memory loss caused by BZDs often affects a victim's ability to recall events, making legal cases more challenging. This review aims to comprehensively synthesize the current knowledge on the use of BZDs in DFCs, their neuropharmacological mechanisms, and the challenges associated with their detection. It also discusses legal issues and emerging forensic tools that may help overcome the current limitations. By addressing this issue from medical, forensic, and legal perspectives, this review aims to recommend better prevention strategies, more effective investigations, and stronger legal outcomes for cases involving benzodiazepine-facilitated crimes.

Introduction: Exposure to teratogenic compounds during pregnancy can lead to significant birth defects. Given the considerable variation in drug responses across species, along with the financial and ethical challenges associated with animal testing, the development of advanced human-based in vitro assays is imperative for effectively identifying potential human teratogens. Previously, we developed a human induced pluripotent stem cells (hiPSCs)-based biomarker assay, ReproTracker, that follows the differentiation of hiPSCs into hepatocytes and cardiomyocytes. The assay combines morphological profiling with the assessment of time-dependent expression patterns of cell-specific biomarkers to detect developmental toxicity responses.

Methods: To further increase the predictability of the assay in identifying potential teratogens, we added differentiation of hiPSCs towards neural rosette-like cells. We evaluated the performance of the extended assay with a set of 51 well-known in vivo teratogens and non-teratogens, including the compounds listed in the ICH S5 reference list.

Results: The optimized assay correctly identified (neuro)developmental toxicants that were not detected in the hepatocyte and cardiomyocyte differentiation assays. These compounds selectively downregulated gene and protein expression of the neuroectodermal marker PAX6 and/or neural rosette marker NESTIN in a concentration-dependent manner and disrupted the differentiation of hiPSCs towards neural rosette-like cells. Overall, based on the current dataset, the addition of neural commitment improved the assay accuracy (from 72.55% to 86.27%) and sensitivity (from 67.50% to 87.50%), when compared to the previously described assay.

Discussion: In summary, trilineage differentiation expanded the spectrum of teratogenic agents detectable by ReproTracker, making the assay an invaluable tool for early in vitro teratogenicity screening.

Microplastics are a troubling consequence of modern civilization, permeating ecosystems worldwide and posing a risk to both the environment and human health. As studies have revealed their extensive distribution throughout bodies of water, soil, and the atmosphere, the ecological crisis and health issues linked to microplastics have become a significant concern within the global scientific community. These tiny particles can enter the human body through various routes, including ingestion, inhalation, and even skin contact, and they have been shown to cross critical barriers such as the placental and blood-brain barriers. Their accumulation in the food chain disrupts the delicate balance of ecosystems and may impair cognitive function and behavioral patterns in living organisms. Alarmingly, there is increasing evidence suggesting that microscopic particles may contribute to the increasing rates of neurodegenerative diseases. This paper reviews the pathways through which microplastics are ingested, their effects on biological functions, and the potential mechanisms that contribute to their neurotoxicity. We emphasize the urgent need for further research to elucidate the toxicological impacts of microplastics and devise effective strategies for mitigating their effects on both ecosystems and human health.

Human metabolically competent HepaRG™ (HepaRG) cells have been developed as a human-relevant New Approach Methodology (NAM) in genetic toxicology, providing a non-animal alternative to rodent-based mutagenicity testing following a positive Ames test. Error-corrected next-generation sequencing (ecNGS) offers improved sensitivity, specificity, and mechanistic insight in genotoxicity and mutagenicity assessment.

Methods: We applied duplex sequencing, an ecNGS approach, to quantify chemically induced point mutations in metabolically competent HepaRG cells. Cells were exposed to a diverse panel of genotoxic agents, including ethyl methanesulfonate (EMS), N-ethyl-N-nitrosourea (ENU), benzo[a]pyrene (BAP), cisplatin, cyclophosphamide, and etoposide. Mutation frequency, substitution patterns, and mutational signatures were analyzed, and results were compared with complementary cytogenetic endpoints.

Results: Duplex sequencing detected dose-responsive increases in mutation frequency for ENU and EMS, with distinct substitution patterns consistent with alkylating mechanisms. BAP and cisplatin induced modest increases in mutation frequency and C>A-enriched spectra, while cyclophosphamide yielded minimal mutagenicity under the tested conditions. Etoposide triggered strong cytogenetic responses without increasing point mutations, consistent with its clastogenic mode of action. COSMIC mutational signature analysis revealed modest enrichment of SBS4 (BAP), SBS11 (EMS), and SBS31/32 (cisplatin), supporting the mechanistic relevance of the model.

Discussion: These findings demonstrate the reproducibility and specificity of ecNGS for detecting low-frequency point mutations and characterizing mutational mechanisms. When combined with complementary cytogenetic assays, duplex sequencing enables a more complete and human-relevant evaluation of genotoxic potential. This study supports the integration of ecNGS into next-generation genotoxicity testing strategies as a NAM for regulatory decision-making.

Background: Vancomycin (VM) is widely used for treating life-threatening infections caused by Gram-positive bacteria resistant to other antibiotics. However, its nephrotoxic effects limit clinical use.

Objective: This study aimed to evaluate the protective effects of Daflon (DF) and Centrum (CE) against VM-induced nephrotoxicity in male rats.

Methods: Fifty healthy male Wistar rats were randomly divided into five groups. Group 1 (negative control) received saline intraperitoneally (IP) for 7 days followed by oral distilled water for 7 days. Group 2 (positive control) received VM (400 mg/kg BW, IP) for 7 days. Group 3 received VM for 7 days followed by DF (100 mg/kg BW, oral) for 7 days. Group 4 received VM for 7 days followed by CE (15 mg/kg BW, oral) for 7 days. Group 5 received VM for 7 days followed by combined DF and CE treatment for 7 days. Blood and kidney samples were collected for hematological, biochemical, molecular, comet assay, and histopathological evaluations.

Results: VM administration significantly elevated serum creatinine, urea, and uric acid levels (p < 0.01), increased renal malondialdehyde (MDA), and reduced catalase (CAT) and superoxide dismutase (SOD) activities (p < 0.05). It also induced marked histological changes and increased DNA fragmentation. DF and CE, particularly in combination (Group 5), significantly reduced renal injury, DNA fragmentation, and histopathological alterations. The protective effect followed the order: G5 > G4 > G3 > G2. Furthermore, VM upregulated PARP1, RIP1, KIM1, TNF-α, and IL-1β expression, which were markedly downregulated by DF and CE.

Conclusion: DF and CE attenuated VM-induced nephrotoxicity through antioxidant, anti-inflammatory, and DNA-protective mechanisms. Their combination provided superior renal protection by reducing oxidative stress, inflammation, and apoptosis, while enhancing antioxidant defenses and DNA repair capacity.

Introduction: The association between neurological symptomatology and heavy metal exposure has been reported in the literature. A few cases of extrapyramidal symptomatology and subacute combined degeneration have been described as manifestations of mercury intoxication. We highlight a case of a patient presenting with Parkinsonian features (tremor, rigidity, and bradykinesia), pyramidal deficits, dysarthria, paresthesia, mild cognitive decline, and emotional lability, with proven elevated mercury levels in blood and hair and elevated arsenic in urine.

Case: A 60-year-old man, with history of mercury exposure while working at the Centre for Waste Management and Environmental Protection presented to a neurologist after 10 months of persistent tremors, muscle spasms, paresthesia, and irritability, followed by the onset of bradykinesia, slurred speech, rigidity, insomnia, and subtle cognitive decline. Laboratory investigations revealed functional vitamin B12 and vitamin D deficiencies, while toxicological quantitative analysis showed elevated blood mercury levels (15.2 μg/L) and hair root levels (3 μg/g). MRI of the brain was normal, whereas MRI of the posterior cervical spine detected signs of myelopathy. Florodeoxyglucose (FDG) Positron Emission Tomography (PET) of the brain revealed bilateral temporal and parietal glucose hypometabolism, most pronounced in the left inferior parietal and left superior temporal regions. Single-Photon Emission Computed Tomography (SPECT) imaging of dopaminergic neurons in the striatum was negative, and the patient was unresponsive to levodopa. Multivitamin therapy (vitamins B, E, and D) with selenium, in combination with symptomatic therapy (benzodiazepines, muscle relaxants, and antidepressants) provided minimal relief, leading to the introduction of N-acetyl cysteine, which resulted in moderate improvement of symptoms. Physical and speech therapy were of great importance in this case.

Discussion: This case is unique because it represents the development of therapy-resistant extrapyramidal symptoms over 3 years of mercury exposure, likely leading to subacute combined degeneration due to functional vitamin B12 deficiency. Epidemiological data describe methylmercury poisoning, known as Minamata disease, which presents with -somatosensory deficits, ataxia, parkinsonism, dysarthria, and visual and hearing impairments.

Conclusion: Toxicological screening for heavy metals in blood and urine should be considered in patients presenting with unexplained, levodopa-resistant extrapyramidal symptoms, behavioral and sleep disturbances, cognitive decline, and other non-specific neurological signs.

Animal experiments have long played a central role in biomedical research and toxicology, yet their limitations in translational accuracy and ethical concerns have intensified the demand for reliable alternatives. Antibody-based technologies are versatile tools used to develop non-animal testing methods capable of detecting toxins and evaluating antitoxins. Enzyme-linked immunosorbent assay and lateral flow assays, among other techniques, have demonstrated high specificity, sensitivity, and reproducibility and are useful in diagnostics, therapeutic development, and as platforms to replace traditional animal assays. Recent developments in in vitro systems, including organoids and microphysiological systems, as well as the integration of AI-based in silico models, offer promising directions. Standardization and regulatory acceptance remain key challenges. A coordinated approach can facilitate the development of antibody-based systems to fulfill the goal of the 3Rs.