Short-chain chlorinated paraffins (SCCPs), as persistent organic pollutants, pose potential health threats, yet their toxicological mechanisms remain incompletely elucidated. This study demonstrates that exposure to SCCPs can induce liver injury in mice. Specifically, SCCPs interfere with the expression of intestinal tight junction proteins in a gut microbiota-dependent manner, leading to increased intestinal permeability and a subsequent elevation of serum lipopolysaccharide (LPS) levels. LPS activates the Toll-like Receptor 4 (TLR4)/Nuclear Factor kappa-B (NF-κB) signaling pathway and influences macrophage polarization, thereby inducing pyroptosis-related signaling in the liver. Further investigation reveals that the gut microbiota dysbiosis induced by SCCPs exposure disrupts the intestinal barrier and induces hepatotoxicity in association with downregulating the Wnt/β-catenin pathway. In summary, this study provides evidence that SCCPs contribute to gut-liver axis disruption through gut microbiota dysbiosis and suppression of the Wnt/β-catenin pathway, providing new insights into their toxicological effects.
Sodium valproate (VPA), a first-line broad-spectrum antiseizure medication, has been associated with altered semen quality in clinical settings, but its direct effects on human sperm remain incompletely defined. In this in vitro study, sperm from normozoospermic donors were exposed to VPA concentrations bracketing an estimated seminal exposure range (10, 20, 50, and 100 µM). Sperm motility was evaluated at 1, 2, and 4 h of incubation, whereas other functional parameters and intracellular oxidative/mitochondrial markers were assessed after a 4-h exposure. VPA induced concentration-dependent reductions in progressive and total motility as well as sperm penetration capacity, without affecting viability or spontaneous acrosome reaction. These functional impairments were accompanied by elevated intracellular oxidative stress and lipid peroxidation, decreased ATP content, depolarization of mitochondrial membrane potential, and ultrastructural mitochondrial abnormalities. Notably, co-incubation with 10 µM resveratrol partially attenuated the oxidative stress-related changes and motility impairment induced by VPA. Taken together, acute in vitro exposure of mature ejaculated human sperm to VPA at concentrations covering the estimated seminal exposure range is associated with impaired sperm function, increased oxidative stress markers and lipid peroxidation, as well as mitochondrial dysfunction-associated changes. Resveratrol co-incubation partially attenuates selected VPA-associated reproductive impairments. These findings provide mechanistic, hypothesis-generating evidence at the level of mature ejaculated sperm; however, they do not establish the mechanisms of chronic VPA-associated reproductive toxicity in men with epilepsy or support clinical antioxidant supplementation. Further in vivo and translational clinical studies are warranted to verify the reproductive relevance of these findings in patients receiving long-term VPA therapy.
Current oxime antidotes exhibit poor blood-brain barrier (BBB) penetration due to their permanent positive charge, limiting the reactivation of organophosphorus (OP)-inhibited cholinesterases in the central nervous system. To address this limitation, the present study investigates nine lipophilic cholesterol- and quinoline-based oximes as potential reactivators of human acetylcholinesterase (hAChE) and butyrylcholinesterase (hBChE) inhibited by OP compounds. Several oximes exhibited strong reversible inhibition with pronounced potency toward hBChE (Ki as low as 4.6 nM). However, despite the favourable binding affinities, reactivation assays using sarin- and cyclosarin-inhibited enzymes revealed negligible recovery of enzymatic activity compared with the standard antidote pralidoxime (2-PAM). Molecular modelling of near-attack conformations showed that the oxime group of the most potent inhibitor adopted an unproductive orientation relative to the catalytic serine. These results highlighted that binding affinity alone is insufficient for effective reactivation; precise positioning of the oxime moiety to enable nucleophilic access to the phosphorus centre is critical. Therefore, a strategic framework for designing next-generation oxime reactivators based on such structures is needed to improve functional efficacy. Moreover, the moderate cytotoxicity of nitronesteroids in hepatocarcinoma (HepG2) and neuroblastoma (SH-SY5Y) cell lines warrants further studies to assess their implications for the compounds' therapeutic potential and safety profile.
Microplastics (MPs) and nanoplastics (NPs) are emerging contaminants that are continuously altered by weathering processes, including light exposure, after their release into the environment. This review provides an overview of the physicochemical transformations and associated cytotoxic effects of photoaged MPs/NPs across various biological models. Current evidence indicates that photoaging substantially alters the physicochemical properties of MPs/NPs. These transformations may influence particle dispersion, cellular uptake, and particle-cell interactions. Photoaged MPs/NPs have been associated with reduced cell viability and other cytotoxicity-related changes in various biological models. Although photoaged MPs/NPs generally exhibited greater toxicity than their pristine counterparts, the magnitude and nature of these effects varied considerably across studies, likely reflecting differences in polymer type, photoaging conditions, particle size, exposure scenarios, and biological models. Overall, existing evidence indicates that photoaging can modify, and often enhance, the cytotoxicity of MPs/NPs. Further studies are needed to improve the comparability and environmental relevance of photoaging protocols, implement more comprehensive particle characterization, and elucidate the mechanisms linking photoaging-induced transformations to biological effects.
Non-communicable diseases (NCDs) are increasing globally. Numerous studies have associated pesticide exposure with metabolic alterations in skeletal muscle and the development of related NCDs. Transfluthrin (TF), a volatile type-I pyrethroid insecticide, is widely used as a household mosquito repellent. Although effective in preventing mosquito-borne diseases, recent in vitro and in vivo studies have implicated it in oxidative stress and genotoxic effects. However, its effects on skeletal muscle remain poorly characterized. This study investigated the dose-dependent subtoxic effects of TF on skeletal muscle cell integrity using C2C12 myotubes. Subtoxic concentrations (10 µM, 25 µM, and 50 µM) were selected via MTT assay, and cultured myotubes were exposed to TF for 24 h. Along with altered morphology, TF-treated myotubes showed a dose-dependent increase in glucose consumption and uptake. TF disrupted glucose metabolism, as evidenced by reduced glycogen storage and elevated lactate production. In addition, mitochondrial dysfunction was confirmed by decreased MTT reduction, reduced succinate dehydrogenase activity, and membrane depolarization. TF induced oxidative stress, reflected by increased reactive oxygen species (ROS) lipid peroxidation (LPO), and catalase activity, along with reduced glutathione (GSH) levels in treated myotubes. Immunostaining further revealed myotube atrophy in TF-treated myotubes, associated with increased calpain activity and MuRF-1 protein expression. This study demonstrates, for the first time, that TF directly impairs skeletal muscle cell metabolism by inducing oxidative stress, mitochondrial dysfunction, atrophy, and altered glucose utilization, highlighting under-recognized health risks associated with excessive routine household insecticide exposure.
Phomopsins are mycotoxins mainly contaminating lupin-derived food matrices posing safety concerns, with phomopsin A considered the most potent congener. Their toxicity is linked to disruption of microtubule dynamics, yet the shortage of toxicokinetic and toxicodynamic data prevents adequate human risk assessment, representing a critical gap for food safety. To bridge this data gap through New Approach Methodologies (NAMs), a computational 3D modelling pipeline, combining molecular dynamics simulations and binding free energy calculations, was applied to investigate the interactions of phomopsin A and selected congeners with the human α/β-tubulin assembly. The whole set of phomopsins showed a comparable mode of binding, with some exhibiting geometrically and energetically distinct, yet comparably stable, interaction profiles. Dechlorination emerged as a critical destabilising factor. By enabling a mechanism-based read-across across the congeneric series, these findings provide a supported hazard prioritisation of phomopsin analogues, identifying phomopsin A, iso-phomopsin A, and phomopsinamine A as high-priority compounds for toxicological investigation. Overall, this NAMs-driven approach sets the groundwork for a more informed hazard characterisation and mechanistic interpretation of the phomopsin family. By helping prioritise which congeners warrant further investigation, it also provides a useful basis for future human exposure assessment, once complemented by toxicokinetic and occurrence data.
Concerns about chronic exposure to titanium dioxide nanoparticles (TiO2-NPs) have increased because of their widespread use in consumer products and subsequent environmental release. Previous studies have shown that TiO2-NPs exert neurotoxic effects and may contribute to Parkinson's disease (PD)-related neurodegenerative processes. However, the molecular mechanisms underlying TiO2-NPs-induced neurotoxicity remain unclear. We investigated these effects and their potential mechanisms in A53T α-synuclein transgenic mice and SH-SY5Y cells. Repeated oral exposure to TiO2-NPs for two months dose-dependently aggravated motor dysfunction and neuronal degeneration in the substantia nigra pars compacta at 1, 10, and 50 mg/kg body weight. In SH‑SY5Y cells, exposure to TiO2‑NPs for 48 h at 0.01, 0.1, 1, 10, 50, and 100 mg/L reduced cell viability in a concentration-dependent manner, impaired mitochondrial function, increased reactive oxygen species (ROS) production and promoted apoptosis. Western blotting showed that TiO2-NPs inhibited PI3K/Akt signaling and altered mitochondrial apoptosis-related proteins, including Bcl-2, Bax, cytochrome C (Cyt C) and caspase-3. The PI3K agonist insulin-like growth factor-1 (IGF-1) partly attenuated these changes. These findings provide mechanistic evidence for TiO2-NPs-induced neurotoxicity and may support the health risk assessment and safe application of TiO2-NPs.
Widespread application of silica nanoparticles (SiNPs) has raised concerns regarding potential neurotoxic risks, yet the complex mechanisms underlying cellular damage remain incompletely understood. Mitochondria-associated endoplasmic reticulum membranes (MAMs), which are regulated by the key tethering protein Mitofusin 2 (Mfn2), serve as crucial platforms for interorgan crosstalk. However, whether ER-mitochondria communication mediated by Mfn2/PERK participate in SiNPs triggered neurotoxicity has not been elucidated. Therefore, this study established an in vitro model of HT22 cells exposed to SiNPs to explore the mechanisms of the mitochondrial dynamic imbalance, ERS and autophagy. We detected cell viability, morphology and ultrastructure, antioxidant function, mtROS, Mfn2/PERK, mitochondrial dynamic, ERS, and autophagy-related proteins to investigate the role of mtROS/Mfn2/PERK in SiNPs-induced damage to HT22 cells. The results showed that the viability of HT22 cells was gradually decreased after exposure to 0-100 μg/mL SiNPs for 24 h. Meanwhile, a series of cellular changes were observed, including oxidative damage, calcium overload, increased intracellular and mitochondrial ROS, decreased ATP content, broken mitochondrial cristae, swollen ER, expression of Mfn2 and PERK. Additionally, the structural and functional integrity of the Mfn2/PERK was impaired, and the expression of mitochondrial dynamics-related proteins was abnormal, thereby inducing ERS and promoting autophagy-related changes. Inhibition of mtROS or ERS and activation of Mfn2 alleviated mitochondrial dynamics imbalance and ERS, and were accompanied by attenuation of SiNPs-induced alterations in Mfn2/PERK signaling and autophagy-related proteins. This further confirms that there is a certain connection between mitochondrial function and ERS after SiNPs exposure, and that autophagy is induced through the mtROS/Mfn2/UPR signaling pathway.
Arsenic (As) is a widespread environmental toxicant that poses severe threats to animal and human health by disrupting multiple cellular processes. In this study, embryonic zebrafish fibroblast cells (ZF4) were used as an in vitro model to investigate the role of Alox12-mediated lipoxygenation in arsenite-induced ferroptosis. Transcriptomic analysis revealed that arsenite exposure (20 μM, 24-48 h) globally induced oxidative stress, apoptosis, cell cycle arrest, and autophagic cell death in a time-dependent manner. Notably, ferroptosis was absent at the early stage but became prominent upon prolonged exposure, coinciding with increased Alox12 expression and 12-HETE production. Overexpression of Alox12 under arsenite stress significantly elevated lipid peroxidation, ROS accumulation, and cell death, whereas siRNA-mediated knockdown of Alox12 partially rescued these phenotypes and restored GPx4 activity. These findings demonstrate that Alox12 mediates the transition from ferroptosis suppression to activation during arsenite toxicity, presenting a checkpoint-like phenotypic phenomenon. This work provides mechanistic insight into arsenism and a potential molecular target for ferroptosis-based therapeutic intervention.
N,N-dimethylformamide is a widely used industrial solvent and a well-recognized occupational hepatotoxicant, which can induce multiple forms of hepatocyte death. However, whether necroptosis, a receptor-interacting protein kinase (RIPK)-dependent programmed necrotic cell death, is the predominant form in N,N-dimethylformamide-induced hepatotoxicity remains unclear. In this study, we identified necroptosis as a major mode of cell demise induced by N,N-dimethylformamide in AML12 hepatocytes (0-40 mM) and cytochrome P450 2E1-overexpressing HepG2 (CYP2E1-HepG2) cells (0-400 mM). N,N-dimethylformamide-induced acute liver injury in C57BL/6 mice (2.0 g/kg bw for 48 h) and AML12 hepatocyte damage (40 mM) were both significantly suppressed by two specific necroptosis inhibitors: necrostatin-1 (targeting RIPK1) and necrosulfonamide (targeting mixed lineage kinase domain-like protein, MLKL). Furthermore, conditioned culture medium from N,N-dimethylformamide-exposed hepatocytes induced NOD-like receptor family pyrin domain-containing 3 (NLRP3) inflammasome activation in apoptosis-associated speck-like protein containing a CARD (ASC)-expressing RAW264.7 macrophages (ASC-RAW264.7), which could be blocked by necroptosis inhibitors. Collectively, these findings strongly support a model in which acute N,N-dimethylformamide exposure triggers hepatocyte necroptosis, which in turn activates the NLRP3 inflammasome in liver macrophages and exacerbates inflammatory liver injury by secreting pro-inflammatory cytokines.
Environmental exposure to fluoride and arsenic is a major public health concern in many regions worldwide. Although both toxicants are known to impair skeletal development, the cellular mechanisms underlying their combined effects on skeletal muscle and bone cells remain poorly understood. This study investigated the impact of sodium fluoride (NaF) and arsenic trioxide (As₂O₃) co-exposure, for the first time, in C2C12 myoblasts (at 0.14 mM NaF + 2.4 µM As2O3) and MC3T3 preosteoblasts (at 0.64 mM NaF + 13 µM As2O3). Co-exposure significantly reduced cell proliferation and decreased the expression of the lineage specific transcription factors such as MYOD and RUNX2 in C2C12 and MC3T3 cells, respectively. Both individual and combined treatments increased ROS production, with co-exposure producing the highest oxidative stress. Further, fluoride and arsenic co-exposure exerted its effects by inducing endoplasmic reticulum stress in both cell types which was witnessed by the activation of the unfolded protein response (UPR) pathways. Specifically, in C2C12 myoblasts, co-exposure predominantly activated the PERK-Atf4-Chop pathway while suppressing IRE1α-Xbp1 expression, indicating unresolved ER stress. In contrast, MC3T3 preosteoblasts activated both PERK-Atf4-Chop and IRE1α-Xbp1 pathways, suggesting engagement of adaptive ER stress mechanisms. Collectively, these findings demonstrate that fluoride and arsenic co-exposure disrupts cellular homeostasis by inducing ER stress in both myoblasts and preosteoblasts. The differences in activation of different UPR pathways suggests C2C12 myoblasts to be more susceptible to fluoride and arsenic co-exposure compared to MC3T3 preosteoblasts.
Lead (Pb) is one of the major heavy metal pollutants that induces multi-organ toxicity. Liver is the primary target of Pb, the exposure of which induces hepatotoxicity by triggering hepatocyte cell death. Ferroptosis, a novel iron-dependent form of regulated cell death, has recently been implicated in a variety of heavy metal-induced organ injuries. In this study, we have identified that ferroptosis is involved in acute Pb exposure-induced liver injury. Our results showed that Pb (1 mM) induced ferroptosis in Hepa1-6 cells, as evidenced by the increase of intracellular ferrous levels and lipid peroxidation. Ferrostatin-1 (Fer-1, 20 μM), a ferroptosis inhibitor, alleviated the hepatocyte cell death. Mechanistically, Pb impaired mitochondria and promoted mitochondrial superoxide production. The mitochondrial reactive oxygen species (ROS) subsequently led to lipid peroxidation, and activated endoplasmic reticulum (ER) stress, which in turn promoted autophagy. The induced-autophagy facilitated the degradation of GPX4 and contributed to the destabilization of SLC7A11. MitoTEMPO (200 μM), a mitochondria-targeted antioxidant, effectively attenuated Pb-induced ferroptosis by reducing lipid peroxidation, relieving ER stress, and stabilizing SLC7A11 and GPX4. Furthermore, tauroursodeoxycholic acid (TUDCA, 800 μM in vitro and 150 mg/kg in vivo), a chemical chaperone, protected against Pb-induced hepatocyte ferroptosis and liver injury by preserving mitochondrial integrity, suppressing ER stress dependent autophagy, and restoring SLC7A11 and GPX4 expression. Our results indicated that mitochondrial ROS may serve as the upstream trigger of Pb-induced ferroptosis, not only facilitating lipid peroxidation, but also impairing the antioxidant defense system. Collectively, our findings reveal a novel hierarchical cascade, mitochondrial ROS-driven ER stress leading to autophagic degradation of GPX4, as a core mechanism of Pb-induced hepatic ferroptosis. Furthermore, TUDCA was identified as a potential therapeutic agent for Pb-induced hepatotoxicity.
Per- and polyfluoroalkyl substances (PFAS) are persistent environmental contaminants widely detected in human biological samples. As regulatory restrictions on long-chain PFAS such as PFOA and PFOS have increased, short-chain alternatives, including perfluorohexanoic acid (PFHxA) have been widely adopted due to their lower bioaccumulation potential. However, their potential neurodevelopmental effects remain poorly understood. In this study, we investigated the long-term behavioral and neurobiological consequences of chronic PFHxA exposure beginning during the neurodevelopmental period and continuing throughout the lifespan. Behavioral assessments revealed that PFHxA exposure selectively impaired spatial memory. In both the novel object recognition and object location tests, PFHxA-exposed mice failed to show a significant preference for novel or relocated objects, indicating deficits in recognition and spatial memory. In contrast, no significant differences were observed in long-term memory, motor function, or social behaviors. Collectively, these findings suggest that chronic PFHxA exposure may induce subtle cognitive alterations and highlight the potential neurodevelopmental hazard of this short-chain PFAS.
Deoxynivalenol (DON) is a trichothecene mycotoxin frequently detected in cereal-derived foods and animal feed. Exposure to DON has been associated with a variety of toxic effects, including neurotoxicity. Three-dimensional (3D) cell culture systems have emerged as more physiologically relevant models than conventional two-dimensional (2D) cultures, as they better reproduce cellular organization, including cell-cell and cell-matrix interactions, and more accurately reflect in vivo conditions. In this context, the present study aimed to investigate the cytotoxic effects of DON and its underlying mechanisms using a 3D spheroid model derived from the human neuroblastoma cell line SH-SY5Y. Spheroids were exposed to different concentrations of DON and cell viability was assessed using the MTT assay, yielding an IC₅₀ value > 64 µM. No significant changes were detected in total intracellular reactive oxygen species (ROS) levels. However, a significant increase in mitochondrial superoxide production was observed at 16 µM, together with alterations in mitochondrial membrane potential between 2 and 16 µM. In addition, DON treatment altered cell cycle progression and increased the proportion of early apoptotic cells at 16 µM, as determined by Annexin V/propidium iodide staining. Protein analysis further revealed increase expression of Bax and Bcl-2 at 16 µM, resulting in a Bax/Bcl-2 ratio close to unity, along with elevated levels of cleaved caspase-3. Overall, these results demonstrate that DON induces cytotoxic effects in SH-SY5Y spheroids, accompanied by mitochondrial alterations, increased mitochondrial superoxide production, and apoptotic cell death. These findings contribute to the understanding of DON-induced alterations in neuronal cells and highlight the potential of SH-SY5Y spheroids as a biologically relevant human in vitro model for mechanistic studies of mycotoxin toxicity.
To advance next-generation risk assessment of non-genotoxic carcinogens, robust mechanism-based assays are essential. A recognized mode of action for non-genotoxic carcinogens is induction of oxidative stress leading to regenerative proliferation. Most of the currently available New Approach Methodologies (NAMs) rely on simple high-throughput cell models with limited biological complexity and often lack metabolic capacity. In this study, we quantify chemically-induced oxidative stress in zebrafish embryos (ZFE), Danio rerio, to evaluate the added value of a whole-organism model with functional metabolism over a simple high-throughput hepatocyte cell line. Four-day-old ZFE were exposed to a set of 22 chemicals, including fifteen chemicals inducing oxidative stress and seven with another primary mode of action. Following 24 h of exposure, reactive oxygen species (ROS) were quantified in the ZFE using the dichloro-dihydro-fluorescein (DCFH) assay. Using analytically determined internal concentrations, chemicals were ranked based on their ROS-inducing potential. Results were compared with ROS induction in maturated HepG2 cells, where DCFH fluorescence was quantified during the first hour of chemical exposure. Both models identified nine chemicals with ROS-inducing potency, although the identified chemicals did not completely overlap. Of the fifteen chemicals reported to primarily induce oxidative stress, only four were not detected by either model. In ZFE, three of the seven chemicals reported to have another primary mode of action than oxidative stress were flagged for ROS production, whereas none of these seven were flagged in maturated HepG2 cells. We explore potential explanations for discrepancies between the models and discuss their applicability in a regulatory context.
Isopropoxate (IPPO), an emerging imidazole ester-type new psychoactive substance, poses potential risks to public health and the environment, yet its neurotoxic mechanisms remain poorly understood. In this study, 8-week-old C57BL/6 J mice were used to evaluate the effects of IPPO on the blood-brain barrier (BBB), oxidative stress, neuroinflammation, and neurotransmitter receptor systems through UPLC-MS/MS-based tissue distribution analysis, quantitative real-time PCR, TUNEL staining, and molecular docking. At a dose of 3 mg/kg, IPPO accumulated in brain tissue and induced cerebral edema. Marked reductions in the tight-junction proteins Occludin and Claudin-5, together with decreased expression of the efflux transporter genes Abcb1a and Abcb1b, indicated impairment of blood-brain barrier (BBB) integrity. In brain tissue, malondialdehyde (MDA) increased by approximately 30%, catalase (CAT) activity decreased by approximately 20%, and glutathione (GSH) content declined by approximately 8%, demonstrating enhanced lipid peroxidation (LPO) and weakened antioxidant defenses. IPPO exposure also upregulated components of the NLRP3 inflammasome and the pro-inflammatory mediators IL-1β, IL-6, and TNF, while reducing the anti-inflammatory cytokine IL-10 by approximately 26%, indicating disruption of the pro-/anti-inflammatory balance. Within neurotransmitter systems, DRD1 and GABRA1 protein levels increased, Taar1 expression decreased, and the immediate-early genes Fos and Arc were markedly upregulated, consistent with dysregulation of dopaminergic, GABAergic, and neuronal activity-related signaling. Molecular docking further indicated stable interactions of IPPO with GABAA and DRD1 receptors, supporting a potential direct influence on neurotransmission through key receptor targets. Transcriptomic profiling corroborated suppression of tight-junction-related genes and disturbance of neurotransmitter-associated pathways. Collectively, these findings identify a coordinated neurotoxic mechanism in which IPPO disrupts the BBB, promotes oxidative stress and neuroinflammation, and alters neurotransmitter receptor signaling.
Vocal fold scarring (VFS) is a debilitating fibrotic disorder lacking molecular biomarkers for early detection or for monitoring toxicant-induced injury. Cigarette smoke toxicity (CST), a major environmental driver of vocal fold fibrosis, disrupts extracellular matrix (ECM) homeostasis; however, the mechanisms linking CST to fibrotic remodeling remain poorly understood. Here, we identify CD44, a hyaluronan receptor, as a key regulator of CST-induced VFS and healthy human vocal fold fibroblast (hVFF) homeostasis. CD44 depletion reduced elastin, collagen, and lysyl oxidase mRNA expression and increased conditioned medium viscosity, demonstrating its essential role in maintaining ECM composition and viscoelastic properties. Cigarette smoke extract (CSE; 2.5-20%) induced concentration-dependent morphological alterations and cytotoxicity in hVFFs. At the median lethal concentration (LC₅₀, 5% CSE), exposure increased collagen synthesis, Na⁺/H⁺ exchanger (NHE1) expression, oxidative stress, and p53-mediated apoptosis. CSE promoted degradation of high-molecular-weight hyaluronan (500-1100 kDa) into low-molecular-weight fragments (30.6-550 kDa) within the ECM via CD44 and hyaluronidase but not through CEMIP, leading to glycocalyx disruption, impaired wound repair and profibrotic remodeling. These findings identify the CD44-dependent hyaluronan-catabolic pathway as a central mediator of CST-induced ECM remodeling. CD44 exhibited a context-dependent dual role in hVFF responses to CSE, acting protectively during short-term exposure (5%, 24 h) but promoting detrimental cellular responses with increasing CSE concentration (≥5%) and prolonged exposure (≥72 h). A synergistic pair of small-molecule inhibitors targeting CD44 signaling and structural integrity reduced oxidative stress, normalized intracellular pH, maintained hyaluronan homeostasis, suppressed p53 expression, restored CD44 expression, attenuated inflammation, and improved wound healing. Collectively, these findings identify CD44 as a promising molecular indicator of early VFS-associated changes and a potential therapeutic target for CST-induced profibrotic remodeling.
Microcystin LR (MC LR) and cylindrospermopsin (CYN) are cyanobacterial toxins commonly detected during harmful algal blooms in freshwater systems. Their increasing occurrence raises concerns about water quality and potential risks to human health. Although the liver is their target organ, these cyanotoxins can also affect the nervous system. The potential neurotoxicity of MC-LR and CYN is still scarcely investigated, particularly for CYN. In this study, the effects of both cyanotoxins on neural progenitor cells were evaluated. MC-LR did not significantly affect cell viability at concentrations up to 60 µM, whereas CYN induced evident cytotoxicity starting at 1 µM after 24-48 h. Additionally, CYN was also tested in BrainSpheres (also called brain microphysiological system, bMPS) for the first time. Statistically significant cytotoxicity was observed from 1 µM onward after 1 week exposure. Downstream analysis revealed that subcytotoxic concentrations of CYN altered the gene expression of different nervous (TUBB3, NEFH, SYP, OLIG1, and GFAP), inflammatory (IL-1β, TNF-α and Nf-κβ) and oxidative stress (SOD1, HMOX and GSTT) markers analysed by RT-qPCR. Overall, the results obtained showed that BrainSpheres is an effective new approach methodology for evaluating the neurotoxic potential of cyanotoxins and points out the importance of including neurotoxicity in the risk assessment of cyanotoxins to human health.
Nanoplastics (NPs) can cross the human biological barriers, enter the bloodstream, and accumulate in vital organs due to their unique physical and chemical properties. This review provides a detailed explanation of the mechanisms by which NPs cross the air-blood, intestinal, and blood-brain barriers. It provides more insight into how NPs interact with blood components after entering circulation, assesses the cardiovascular toxicity that results, and visually represents how NPs are distributed in human tissues. Traditional static models have significant limitations in simulating the complex physiological microenvironments of the human body. Organ-on-a-chip (OoC) technology is emerging as a novel toxicology tool due to its unique advantages in dynamically reconstructing the vascular microenvironment and biological barriers. This technology allows for a precise characterization of the hemodynamic behavior of NPs and their mechanisms of cross-barrier toxicity. In general, this work offers crucial theoretical and methodological insights to address existing technical issues in assessing the toxicity of emerging environmental contaminants.
Polystyrene nanoplastics (PS-NPs) are emerging environmental contaminants with unclear cardiovascular impacts. This study evaluated PS-NPs-induced endothelial senescence using murine models and HUVECs. PS-NPs caused aortic wall thickening and structural disruption in mice, and induced DNA damage, apoptosis, cell cycle arrest, and impaired migration/vasculogenesis in vitro. Both models showed excessive ROS production and nucleolar stress (NPM1 relocalization), leading to premature senescence via p53/p21 upregulation. These effects were reversed by NPM1 inhibitor NSC348884 or ROS scavenger N-acetylcysteine. Collectively, PS-NPs promote vascular endothelial senescence through ROS-dependent nucleolar stress, highlighting their vasotoxic potential and cardiovascular risks.
