Api AM, Bartlett A, Belsito D
… +31 more, Botelho D, Bruze M, Bryant-Friedrich A, Burton GA, Cancellieri MA, Chon H, Cronin M, Crotty S, Dagli ML, Dekant W, Deodhar C, Farrell K, Fryer AD, Jones L, Joshi K, Lapczynski A, Laskin DL, Lavelle M, Lee I, Moustakas H, Muldoon J, Penning TM, Piersma AH, Ritacco G, Sadekar N, Schember I, Schultz TW, Siddiqi F, Sipes IG, Sullivan G, Thakkar Y
Ethyl octadecanoate was evaluated for genotoxicity, repeated dose toxicity, reproductive toxicity, local respiratory toxicity, photoirritation/photoallergenicity, skin sensitization, and environmental safety. Data show t...Ethyl octadecanoate was evaluated for genotoxicity, repeated dose toxicity, reproductive toxicity, local respiratory toxicity, photoirritation/photoallergenicity, skin sensitization, and environmental safety. Data show that ethyl octadecanoate is not genotoxic. Data on ethyl octadecanoate provide a calculated Margin of Exposure (MOE) > 100 for the repeated dose toxicity and reproductive toxicity endpoints. Data from read-across analog methyl hexadecanoate (CAS # 112-39-0) provided ethyl octadecanoate a No Expected Sensitization Induction Level (NESIL) of 2400 μg/cm for the skin sensitization endpoint. The photoirritation/photoallergenicity endpoints were evaluated based on ultraviolet/visible (UV/Vis) spectra; ethyl octadecanoate is not expected to be photoirritating/photoallergenic. The local respiratory toxicity endpoint was evaluated using the Threshold of Toxicological Concern (TTC) for a Cramer Class I material, and the exposure to ethyl octadecanoate is below the TTC (1.4 mg/day). The environmental endpoints were evaluated; ethyl octadecanoate was found not to be Persistent, Bioaccumulative, and Toxic (PBT) as per the International Fragrance Association (IFRA) Environmental Standards, and its risk quotients (RQs), based on its current volume of use (VoU) in Europe (EU), North America (NA), Asia-Pacific (AP), and South America (SA) (i.e., Predicted Environmental Concentration/Predicted No Effect Concentration [PEC/PNEC]), are <1.
Api AM, Bartlett A, Belsito D
… +31 more, Botelho D, Bruze M, Bryant-Friedrich A, Burton GA, Cancellieri MA, Chon H, Cronin M, Crotty S, Dagli ML, Dekant W, Deodhar C, Farrell K, Fryer AD, Jones L, Joshi K, Lapczynski A, Laskin DL, Lavelle M, Lee I, Moustakas H, Muldoon J, Penning TM, Piersma AH, Ritacco G, Sadekar N, Schember I, Schultz TW, Siddiqi F, Sipes IG, Sullivan G, Thakkar Y
TSC6-peptide is an 8-amino acid synthetic peptide compound that inhibits intestinal α-amylase upon oral administration to control the digestion and absorption of starchy foods. However, its toxicological safety and other...TSC6-peptide is an 8-amino acid synthetic peptide compound that inhibits intestinal α-amylase upon oral administration to control the digestion and absorption of starchy foods. However, its toxicological safety and other scientific evidence remain to be established. Given the potential utility of TSC6-peptide as an α-amylase inhibitor, this study conducted in vivo and in vitro experiments to support its safety profile. In reverse mutation and mammalian micronucleus assays revealed no genotoxicity for TSC6-peptide. Meanwhile, in the 90-day dietary toxicity study in rats, the NOAEL was 500 mg/kg bw/day for male rats following TSC6-peptide administration and the LOAEL for female rats was 50 mg/kg bw/day. These results indicate that TSC6-peptide possesses controllable safety as an α-amylase inhibitor.
BACKGROUND: Cosmetic use is increasingly common among young college students; however, its potential link to hepatic steatosis remains unclear. This exploratory study examined associations between external cosmetic use,...BACKGROUND: Cosmetic use is increasingly common among young college students; however, its potential link to hepatic steatosis remains unclear. This exploratory study examined associations between external cosmetic use, internal metal exposure, and hepatic steatosis indices, as well as the possible mediating roles of adipokines. METHODS: A panel study with 70 college students collected cosmetics exposure data, quantified serum levels of 26 metals, and measured plasma adipokine levels. Hepatic steatosis was assessed using the HSI and ZJU index as non-invasive indirect biomarkers. Generalized linear models (GLM) and generalized weighted quantile sum (gWQS) models evaluated associations between cosmetic and metal exposure with HSI, ZJU, and adipokines, including the interaction between sex and cosmetic exposure-related metals. Causal mediation analysis assessed adipokine mediation effects. RESULTS: Exposure to cosmetics, particularly hair and body products, was associated with elevated HSI and ZJU in college students. Cobalt (Co) and copper (Cu), biomarkers of cosmetic exposure, exhibited positive dose-response relationships with HSI, ZJU, and leptin, independent of sex. Leptin mediated the associations between lip and hair cosmetics, Co, Cu, and increased HSI and ZJU. CONCLUSIONS: Co and Cu biomarkers indicate an association between cosmetic use and biomarkers of hepatic steatosis in college students, in which leptin may play a mediating role. This exploratory study offers preliminary epidemiological evidence and suggests potential intervention targets for cosmetics-related liver health risks. However, given the indirect nature of HSI and ZJU and the observational design, causality cannot be inferred; further investigations are warranted.
Azetidine-2-carboxylic acid (A2C) is a non-canonical amino acid (NCAA) produced by several plant species, including Beta vulgaris cultivars such as sugar beet. A2C can be incorporated into proteins in place of proline. T...Azetidine-2-carboxylic acid (A2C) is a non-canonical amino acid (NCAA) produced by several plant species, including Beta vulgaris cultivars such as sugar beet. A2C can be incorporated into proteins in place of proline. The presence of A2C in myelin basic protein has been implicated in the pathogenesis of multiple sclerosis. Human exposure to A2C could arise from the use of fodder beets and sugar beet by-products as livestock feed. A2C is pro-inflammatory, pro-apoptotic, and induces mitochondrial dysfunction. Animal studies have examined A2C-related skeletal development anomalies linked to its incorporation into collagen. In murine models, A2C induces morphological alterations in oligodendrocytes, the myelin-producing cells. In the present study, we employed an untargeted metabolomics approach to characterise global changes in neuroblastoma cells following A2C exposure. Using spectral libraries for metabolite identification, and pathway mapping to assess cellular changes, we observed a global reduction in protein synthesis and depletion of major intracellular antioxidants following A2C exposure. This is consistent with ER stress triggered by the accumulation of aberrant A2C-containing proteins and a disruption of redox homeostasis. These findings provide mechanistic insight into A2C-induced cytotoxicity and advance our understanding of the potential role of NCAAs as environmental triggers of human disease.
BACKGROUND: Food allergy is a potentially serious immune system reaction that significantly impacts the quality of life for individuals. Studies have shown that dysregulation of circular RNAs (circRNAs) mediates the acti...BACKGROUND: Food allergy is a potentially serious immune system reaction that significantly impacts the quality of life for individuals. Studies have shown that dysregulation of circular RNAs (circRNAs) mediates the activation of immune cells and inflammatory mechanisms in allergic diseases. This study aimed to elucidate its functions and the pathways involved in food allergic reactions. METHODS: A Th2-polarized food allergy model was established in BALB/c mice using ovalbumin (OVA) adsorbed to aluminum hydroxide. Allergic responses were evaluated using a combination of clinical scoring, histology (H&E), and transmission electron microscopy (TEM). Serum IgE and cytokines (IL-4, IL-5, IL-13) were measured by ELISA. Molecular expressions were analyzed by western blot and qRT-PCR. RNA immunoprecipitation (RIP) and PAR-CLIP assays validated RNA-protein interactions. RESULTS: circS100A11, EIF4A3, and PKD1 was upregulated in sensitized mice. EIF4A3 was found to bind to and stabilized PKD1 mRNA, and its overexpression exacerbated allergic reactions in a PKD1-dependent manner. circS100A11 was found to directly interact with EIF4A3, promoting the recruitment of EIF4A3 to the PKD1 transcript. circS100A11 knockdown alleviated allergy, which was reversed by EIF4A3 overexpression. The detrimental effects of the circS100A11/EIF4A3 axis were abolished by concurrent PKD1 knockdown. CONCLUSION: Our findings define a novel regulatory pathway in which circS100A11 aggravates food allergy by recruiting EIF4A3 to enhance PKD1 expression, presenting a potential therapeutic target for intervention.
The pervasive environmental presence of nano- and microplastics, particularly polystyrene nanoplastics (PSNPs), has raised increasing concern regarding their potential adverse effects on human health. While epithelial ba...The pervasive environmental presence of nano- and microplastics, particularly polystyrene nanoplastics (PSNPs), has raised increasing concern regarding their potential adverse effects on human health. While epithelial barrier impairment is recognized as a critical toxicological outcome, the oral epithelium remains a poorly understood target despite being the primary gateway for ingested nanoplastics. In this study, we demonstrate that PSNPs induce significant functional impairment of the oral barrier even under sub-cytotoxic conditions (>80% cell viability). Exposure of TR146 human buccal epithelial cell layers to PSNPs triggered an early increase in paracellular permeability (fluorescein isothiocyanate-labeled dextran (4 kDa) flux), followed by a decline in transepithelial electrical resistance. Crucially, these functional deficits occurred in the absence of overt cytotoxicity and were associated with the molecular downregulation and altered distribution of tight junction-related proteins, including ZO-2, occludin, MarvelD3, and claudin-3 and claudin-4. Our findings indicate that PSNP-induced alterations in TJ-related protein distribution may represent an early molecular event associated with oral epithelial barrier dysfunction under sub-cytotoxic conditions. Collectively, this study highlights the oral epithelium as a highly sensitive target and underscores that functional barrier failure, rather than direct cytotoxicity, may represent a key mechanism underlying nanoplastic-associated toxicity.
Torres-Arroyo A, Mendoza-Hernández DA, López-Salgueiro R
… +7 more, López-Hernández E, Amaro-Leal AM, Méndez ST, López-Durán A, Carrasco-Navarro U, Fernández FJ, Reyes-Vivas H
Apple allergy is a manifestation of pollen-food allergy syndrome (PFAS). Mal d 1 is the major apple allergen and a key driver of cross-reactivity with birch and related tree pollens. Its biochemical properties remain inc...Apple allergy is a manifestation of pollen-food allergy syndrome (PFAS). Mal d 1 is the major apple allergen and a key driver of cross-reactivity with birch and related tree pollens. Its biochemical properties remain incompletely characterized. This work aimed to comprehensively characterize the physicochemical, structural, and immunological properties of a recombinant Mal d 1 (rMal d 1) isoform and to assess its clinical relevance in apple-allergic Mexican pediatric patients (MPP) with PFAS. Its molecular mass, structural stability, folding, resistance to denaturation, and proteolysis were analyzed. Its IgE reactivity, skin prick tests (SPT), and basophil activation tests (BAT) were performed in MPP. The protein was named rMal d 1.02 since its primary structure identity was 98% with this isoallergen group. It was monomeric and exhibited fully reversible unfolding under heat and urea denaturation, significant stability under acidic pH, and high resistance to trypsin but susceptibility to pepsin. It demonstrated IgE reactivity, and SPT and BAT positivity in allergic patients. Due to its immunoreactivity, it highlights its significance as a key allergen in MPP. Its resistance to digestion and denaturation may explain persistent allergenicity after food processing. rMal d 1.02 is valuable for diagnosing and may inform future immunotherapeutic approaches.
Maternal exposure to endocrine-disrupting compounds (EDCs) is linked to male reproductive decline, yet the mechanisms underlying developmental programming of long-term reproductive toxicity remain elusive. This study inv...Maternal exposure to endocrine-disrupting compounds (EDCs) is linked to male reproductive decline, yet the mechanisms underlying developmental programming of long-term reproductive toxicity remain elusive. This study investigated how prenatal exposure to the anti-androgenic fungicide flutamide impairs spermatogenesis in offspring. Pregnant Sprague-Dawley rats were treated with flutamide (25 mg/kg/d) during late gestation (GD12-GD20). Testicular morphology and spermatogenic markers (Stra8, PCNA) were assessed in male offspring at PND30 and PND60. RNA-sequencing (RNA-seq) identified differentially expressed genes, while RARα antagonism (AR7) and Retinoic Acid (RA) rescue experiments were conducted in vivo and in testicular organ cultures to validate the mechanism. Prenatal flutamide exposure significantly reduced sperm count and disrupted seminiferous tubule architecture. RNA-seq revealed significant alterations in the RARα signaling pathway and oxidative stress-related genes. Mechanistically, flutamide suppressed RARα expression, which in turn triggered NLRP3 inflammasome activation. Inhibition of RARα by AR7 mimicked flutamide-induced spermatogenic defects and oxidative stress, whereas RA treatment significantly attenuated these toxic effects by restoring RARα/NLRP3 homeostasis. Our findings demonstrate that the RARα-NLRP3 axis is a critical mediator of flutamide-induced developmental reproductive toxicity, highlighting RARα as a potential therapeutic target for mitigating EDC-induced male infertility.
Triphenyl phosphate (TPhP), a prevalent organophosphate flame retardant (OPFR), exhibits environmental persistence, bioaccumulation, and biotoxicity. Although emerging evidence suggests its hepatotoxicity, the precise mo...Triphenyl phosphate (TPhP), a prevalent organophosphate flame retardant (OPFR), exhibits environmental persistence, bioaccumulation, and biotoxicity. Although emerging evidence suggests its hepatotoxicity, the precise molecular mechanisms remain incompletely defined. This study employed an integrative strategy to study the mechanisms. Network analysis identified hepatotoxicity targets by intersecting TPhP-associated targets with liver disease targets. Subsequently, protein-protein interaction networks prioritized seven hub genes (SRC, PPARG, AKT1, EP300, EGFR, PTGS2, and GAPDH) using topological algorithms. For structural validation, molecular docking and dynamics simulations were employed to evaluate the binding stability between TPhP and these targets. Functional enrichment analyses implicated phospholipid biosynthesis and xenobiotic metabolism, with inflammatory response exacerbating metabolic dysregulation. Quantitative analysis of HepG2 cells treated with TPhP for 24 h demonstrated significant upregulation of PPARG, PTGS2, and EGFR. Microarray analysis in rodent models confirmed 71% concordance (5/7 hub genes) between network-predicted hub genes and rodent transcriptomic data. The results indicate that TPhP exerts hepatotoxicity through multi-target interactions derived from network analysis, primarily involving PPARG/PI3K/AKT1-driven metabolic dysregulation and STAT3/mTORC1-mediated inflammatory cascades associated with PTGS2. Collectively, this integrative study provides evidence that TPhP may compromise lipid raft integrity and autophagy-lysosomal function through PPARG-centered networks, offering novel insights for environmental risk assessment and therapeutic target identification.
Phthalates are plastic-derived endocrine-disrupting chemicals that can migrate into the environment and enter the human body, posing considerable health risks. Di-n-pentyl phthalate (DNPP), a commonly used phthalate, has...Phthalates are plastic-derived endocrine-disrupting chemicals that can migrate into the environment and enter the human body, posing considerable health risks. Di-n-pentyl phthalate (DNPP), a commonly used phthalate, has not been fully characterized with respect to its hepatotoxic effects. In this study, we investigated DNPP-induced liver toxicity and its underlying mechanisms in mice using single-cell RNA sequencing (scRNA-seq). A DNPP-exposed mouse model was established, followed by histological evaluation of liver tissues and measurement of serum transaminase levels. Additionally, scRNA-seq, flow cytometry, and quantitative real-time polymerase chain reaction were performed to assess the changes in cellular subpopulations and gene expression profiles. DNPP exposure substantially increased liver-to-body weight ratio and serum alanine aminotransferase levels in a dose-dependent manner. Histological analysis revealed enhanced lymphocyte infiltration in DNPP-exposed livers. ScRNA-seq analysis demonstrated marked alterations in T-NK, myeloid, and endothelial cells, accompanied by the downregulation of the expressions of genes associated with immune cell chemotaxis, myeloid cell stress response, and endothelial protein synthesis. These findings suggest that DNPP may induce liver injury by disrupting immune homeostasis and impairing cellular functions. Overall, this study provides novel insights into DNPP-induced hepatotoxicity and highlights the need for strengthened monitoring of DNPP in environmental media to safeguard public health.
Tolvaptan (TVP), a vasopressin V2 receptor antagonist for hyponatremia and autosomal dominant polycystic kidney disease, is associated with infrequent yet severe idiosyncratic drug-induced liver injury (IDILI), posing cr...Tolvaptan (TVP), a vasopressin V2 receptor antagonist for hyponatremia and autosomal dominant polycystic kidney disease, is associated with infrequent yet severe idiosyncratic drug-induced liver injury (IDILI), posing critical challenges to clinical medication safety. Toll-like receptor 4 knockout (TLR4-KO) confers protection against drug-induced liver injury, yet its precise role and underlying mechanisms in TVP-induced hepatotoxicity remain unclear. This study investigated the hepatoprotective potential of TLR4-KO against TVP-induced liver injury using acute lipopolysaccharide (LPS)-sensitized mouse and primary hepatocyte models, characterized by 3-day TVP administration and intraperitoneal LPS injection 2 h before the final TVP dose in vivo, and 100 ng/mL LPS and 0-25 μM TVP for 24 h in vitro. Inflammatory stress suppressed TVP metabolism (37 metabolites detected under LPS vs. 47 under normal conditions) via downregulating CYP3A11. TLR4-KO showed a significant protective effect against LPS/TVP-induced hepatotoxicity, evidenced by reduced liver enzymes, attenuated histopathological damage in mice, and decreased aminotransferase activities in primary hepatocytes. Mechanistically, TLR4 knockout reversed abnormal TVP pharmacokinetics and alleviated hepatic accumulation by restoring CYP3A11 and inhibiting inflammatory signaling pathway activation. Additionally, TLR4-KO reversed LPS/TVP-induced hepatic bile acid (BA) accumulation and reduced BA levels in bile/plasma, which correlated with the amelioration of CYP7A1 upregulation and the reversal of farnesoid X receptor and efflux transporter downregulation. The study underscores TLR4 as a pivotal mediator linking TVP metabolism, inflammation, and BA homeostasis disruption in IDILI pathogenesis, providing novel mechanistic insights for mitigating TVP-associated IDILI.
5-Hydroxymethylfurfural (5-HMF), a common by-product of thermal-processed foods, poses a potential risk of intestinal toxicity upon ingestion. However, its underlying toxic mechanisms remain incompletely understood. In t...5-Hydroxymethylfurfural (5-HMF), a common by-product of thermal-processed foods, poses a potential risk of intestinal toxicity upon ingestion. However, its underlying toxic mechanisms remain incompletely understood. In this study, we investigated the effects and potential molecular pathways of 5-HMF using normal human intestinal epithelial cells (HIEC-6). The results showed that 5-HMF inhibited the proliferation of HIEC-6 cells in a concentration-dependent manner and induced apoptosis possibly through both the death receptor and mitochondrial pathways, as evidenced by increased activities of caspase-8 and caspase-9.5-HMF increased intracellular reactive oxygen species (ROS) levels by 1.42 to 2.12 fold, disrupted antioxidant enzymes activities, and increased malondialdehyde content, indicating oxidative damage. Meanwhile, 5-HMF upregulated the mRNA expression of the pro-inflammatory cytokines TNF-α and IL-6 and downregulated the mRNA and protein expression of key tight junction proteins ZO-1, Occludin and Claudin-1, indicating promotion of inflammation and impairment of epithelial barrier. 5-HMF also altered the mRNA expression of MAPK pathway-associated genes and NF-κB, indicating a possible correlation between this signaling cascade and the toxic effects of 5-HMF. Collectively, these findings provide a theoretical foundation for the risk assessment of dietary 5-HMF exposure and for future mechanistic studies on the role of MAPK signaling in 5-HMF-induced intestinal toxicity.
Uncertainty assessment is critical to inform confidence in risk conclusions and guide risk-based decision making. This case study quantifies the impact of uncertainties in the United States Environmental Protection Agenc...Uncertainty assessment is critical to inform confidence in risk conclusions and guide risk-based decision making. This case study quantifies the impact of uncertainties in the United States Environmental Protection Agency (US EPA)'s chronic non-cancer risk evaluation of diisononyl phthalate (DINP) under the Toxic Substances Control Act and provides critical information regarding confidence in risk determinations and risk management decisions. Uncertainties associated with key elements in US EPA's risk determination approach (i.e., margin of exposure [MOE]) were qualitatively and quantitatively examined, including point of departure (POD) selection, exposure estimates, and benchmark MOE (bMOE) calculation, to demonstrate their impact on MOEs and implications for risk-based conclusions. There was medium overall confidence in the risk evaluation, with lowest confidence in POD selection. Quantitative uncertainty assessment for each exposure scenario for which US EPA determined unreasonable risk (i.e., MOE < bMOE of 30) considered a range of alternative values per key element. For the lowest MOE calculated by US EPA (2.7 = unreasonable risk), alternative MOEs derived herein ranged from 117 to 150 (no unreasonable risk), demonstrating the uncertainty imparted in US EPA's determinations of unreasonable risk. This uncertainty assessment illustrates the importance of applying qualitative and quantitative approaches to assess uncertainty to frame the confidence in assessments that underlie risk-based decisions.
Chlorpyrifos (CPF), a typical pesticide used worldwide, is known to induce diabetic symptoms such as hyperglycaemia/decreased insulin levels in mammals, which may be a risk factor for the development of diabetes mellitus...Chlorpyrifos (CPF), a typical pesticide used worldwide, is known to induce diabetic symptoms such as hyperglycaemia/decreased insulin levels in mammals, which may be a risk factor for the development of diabetes mellitus. Nevertheless, the exact mechanisms underlying CPF-mediated pancreatic islet β-cell cytotoxicity remain unclear. This study aimed to investigate the mechanism of CPF-induced toxic responses in β-cells. CPF exposure with the environmentally relevant concentrations significantly inhibited in cell viability and insulin secretion, accompanied with mitochondrial dysfunction, and apoptotic events. Additionally, CPF exposure markedly induced the phosphorylated expressions of Akt, AMPKα, JNK, and ERK1/2, but did not affect p38-MAPK protein expression. Cells pretreated with pharmacological inhibitors of JNK (SP600125) and AMPK (compound C) effectively attenuated the CPF-induced cytotoxicity, and apoptotic events. However, the inhibitors of ERK1/2 (PD98059) or Akt (LY294002) did not prevent the CPF-induced viability reduction and caspase-3 activity increase. Interestingly, both the inhibitors could prevent the CPF-induced JNK and AMPKα protein activation, mutually affecting each other. Collectively, these findings imply that CPF exposure exerts cytotoxicity via a signaling pathway of mitochondria-dependent apoptosis, ultimately contributing to β-cell death. The functional co-activation of JNK and AMPKα signaling-regulated apoptotic pathway may provide a beneficial evidence into the mechanism understanding CPF-elicited β-cell cytotoxicity.
The EFSA's use of a default methodology for establishment of a health-based guidance value (HBGV) from a neurobehavioral study resulted in an acceptable daily intake (ADI) for glutamates (E620-625) of 30 mg/kg bw/day whi...The EFSA's use of a default methodology for establishment of a health-based guidance value (HBGV) from a neurobehavioral study resulted in an acceptable daily intake (ADI) for glutamates (E620-625) of 30 mg/kg bw/day which is below the normal dietary glutamate intake, and lower than the intake of free glutamate by breast fed babies. To resolve this dilemma, the present study investigated the interspecies variability in plasma glutamate levels to define a chemical-specific adjustment factor (CSAF) for the interspecies variation in kinetics (AK). Human, mouse and rat plasma glutamate levels available following the administration of MSG in a standard liquid diet (Sustagen) and water were analysed. The normalized Cmax values resulted in a AK value of 1 following administration in food and 1.4 in water in a fasted state. The administration in a food vehicle being the more applicable mode of dietary consumption for MSG. Combining these numbers with the (HK) for interindividual human differences in glutamate kinetics value of 2 and the default factors for interspecies and interindividual differences in dynamics of 2.5 and 3.16, results in an overall CSAF of 16. This CSAF results in a HBGV for glutamate that is no longer below the acceptable range of oral intake.
Cholesterol accumulation in the brain has been implicated in mitochondrial dysfunction and neurodegeneration; however, its specific effects on mitochondrial quality control pathways, including the mitochondrial unfolded...Cholesterol accumulation in the brain has been implicated in mitochondrial dysfunction and neurodegeneration; however, its specific effects on mitochondrial quality control pathways, including the mitochondrial unfolded protein response (UPR) and mitophagy, remain poorly defined. In this study, SH-SY5Y human neuroblastoma cells were treated with 25 or 50 μg/mL water-soluble cholesterol for 24 h. UPR, mitophagy, and inflammasome activation were assessed using molecular and cellular approaches, including immunoblotting, quantitative RT-PCR, and fluorescence-based imaging. Cholesterol treatment increased intracellular cholesterol levels up to 1.7-fold and induced dose-dependent cytotoxicity and apoptosis. UPRmt was suppressed, as evidenced by reduced expression of mitochondrial chaperones and proteases. In parallel, cholesterol impaired mitophagy by disrupting autophagic flux, leading to the accumulation of damaged mitochondria. This was accompanied by increased cytosolic mitochondrial DNA (mtDNA), caspase-1 activation, and interleukin-1β secretion. These findings indicate that impaired mitochondrial clearance promotes mtDNA release, thereby linking mitochondrial dysfunction to inflammasome activation. Collectively, cholesterol overload disrupts UPRmt and mitophagy, thereby promoting mitochondrial dysfunction, inflammasome activation, and neuronal apoptosis.
Polonium-210 (Po), a highly radiotoxic α-emitter from the U decay chain, represents an underrecognized contributor to tobacco-related health risk. Following inhalation, Po deposits in bronchial and alveolar regions, deli...Polonium-210 (Po), a highly radiotoxic α-emitter from the U decay chain, represents an underrecognized contributor to tobacco-related health risk. Following inhalation, Po deposits in bronchial and alveolar regions, delivering high-LET radiation to sensitive pulmonary tissues. The present study aimed to quantify Po activity and its distribution across tobacco, combustion residues, filters, and mainstream smoke in conventional cigarettes, slim cigarettes, and heated tobacco products (HTPs), and to evaluate inter-product variability using multivariate chemometric approaches. Combustion-based products exhibited substantial transfer of Po to mainstream smoke (ca.70% on average), whereas HTPs showed significantly lower transfer (ca.15%), although absolute Po activities in HTP tobacco matrices remained comparable across categories. Principal component and discriminant analyses revealed partial clustering of HTPs, while conventional and slim cigarettes showed overlapping profiles, indicating limited categorical separation. Regional dose modelling based on ICRP respiratory tract assumptions demonstrated that the alveolar-interstitial compartment accounted for the largest contribution to annual effective dose. These results indicate that naturally occurring radionuclides contribute measurably to the radiological burden of tobacco use across product types and warrant systematic inclusion in toxicological risk assessment frameworks.
Tris (1,3-dichloro-2-propyl) phosphate (TDCIPP) is a widely used organophosphate flame retardant increasingly linked to reproductive toxicity, yet its placental toxic mechanisms remain unclear. This study demonstrates th...Tris (1,3-dichloro-2-propyl) phosphate (TDCIPP) is a widely used organophosphate flame retardant increasingly linked to reproductive toxicity, yet its placental toxic mechanisms remain unclear. This study demonstrates that TDCIPP exposure disrupts placental homeostasis by inducing oxidative stress, which triggers excessive PINK1/Parkin-mediated mitophagy in both human trophoblasts (HTR-8/SVneo) and pregnant mice. Integrated network toxicology analysis predicted mitochondrial dysfunction and oxidative stress as central pathways, validated by upregulation of ATG5 and HMOX1, downregulation of SOD2, elevated ROS and mitochondrial superoxide, loss of mitochondrial membrane potential, and ultrastructural evidence of mitophagic vacuoles. TDCIPP activated the PINK1/Parkin pathway-evidenced by increased PINK1, Parkin, LC3-II/I, p62, reduced TOMM20, and enhanced Parkin-TOMM20 colocalization-while alternative mitophagy receptors FUNDC1 and BNIP3 remained unaffected. Mechanistically, oxidative stress acted upstream, as N-acetylcysteine (NAC) pretreatment suppressed ROS accumulation and PINK1/Parkin activation. Functionally, TDCIPP impaired trophoblast proliferation, induced apoptosis, and caused fetal growth restriction (FGR) in vivo. Notably, both genetic knockdown of Parkin in vitro and pharmacological inhibition of mitophagy with Mdivi-1 in vivo significantly alleviated trophoblast apoptosis and rescued placental and fetal weights. These findings establish that TDCIPP-induced placental injury is driven by an oxidative stress-PINK1/Parkin-mitophagy axis, revealing dysregulated mitophagy as a pivotal mechanism underlying TDCIPP-associated developmental toxicity and offering new insights into the reproductive risks of environmental flame retardant exposure.