This comprehensive review focuses on various dimensions of nanoparticle toxicity, emphasizing toxicological characteristics, assessment techniques, and examinations of relevant studies on the effects on biological systems. The primary objective is to comprehend the potential risks associated with nanoparticles and to provide efficient strategies for mitigating them by consolidating current research discoveries. For in-depth insights, the discussions extend to crucial aspects such as toxicity associated with different nanoparticles, human exposure, and nanoparticle deposition in the human respiratory tract. The analysis utilizes the multiple-path particle dosimetry (MPPD) modeling for computational simulation. The SiO2 nanoparticles with a volume concentration of 1% and a particle size of 50â¯nm are used to depict the MPPD modeling of the Left upper (LU), left lower (LL), right upper (RU), right middle (RM), and right lower (RL) lobes in the respiratory tract. The analysis revealed a substantial 67.5% decrease in the deposition fraction as the particle size increased from 10â¯nm to 100â¯nm. Graphical representation emphasizes the significant impact of exposure path selection on nanoparticle deposition, with distinct deposition values observed for nasal, oral, oronasal-mouth breather, oronasal - normal augmenter, and endotracheal paths (0.00291⯵g, 0.00332⯵g, 0.00297⯵g, 0.00291⯵g, and 0.00383⯵g, respectively). Consistent with the focus of the review, the article also addresses crucial mitigation strategies for managing nanoparticle toxicity.
Nanoparticles , Respiratory System , Humans , Nanoparticles/toxicity , Respiratory System/drug effects , Respiratory System/metabolism , Animals , Risk Factors , Inhalation Exposure/adverse effects , Particle Size , Risk Assessment
OBJECTIVE: While evidence continues to emerge on the negative health effects of electronic cigarettes (e-cigarettes) on the lungs, little is known regarding their deleterious effects on the upper airway. The purpose of this review is to summarize the toxicological effects of e-cigarettes, and their components, on the upper airway. DATA SOURCES: PubMed, SCOPUS, EMBASE databases. REVIEW METHODS: Systematic searches were performed in accordance with Preferred Reporting Items for Systematic Reviews and Meta-analyses guidelines from 2003 to 2023. Studies were included if they investigated the toxicological effects of e-cigarette exposure on human or animal upper airway tissue. Two authors independently screened, reviewed, and appraised all included articles. RESULTS: A total of 822 unique articles were identified, of which 53 met inclusion criteria and spanned subsites including the oral cavity (22/53 studies), nasal cavity/nasopharynx (13/53), multiple sites (10/53), larynx (5/53), trachea (2/53), and oropharynx (1/53). The most commonly observed consequences of e-cigarette use on the upper airway included: proinflammatory (15/53 studies), histological (13/53), cytotoxicity (11/53), genotoxicity (11/53), and procarcinogenic (6/53). E-cigarette humectants independently induced toxicity at multiple upper airway subsites, however, effects were generally amplified when flavoring(s) and/or nicotine were added. Across almost all studies, exposure to cigarette smoke exhibited increased toxicity in the upper airway compared with exposure to e-cigarette vapor. CONCLUSION: Current data suggest that while e-cigarettes are generally less harmful than traditional cigarettes, they possess a distinct toxicological profile that is enhanced upon the addition of flavoring(s) and/or nicotine. Future investigations into underexamined subsites, such as the oropharynx and hypopharynx, are needed to comprehensively understand the effects of e-cigarettes on the upper airway.
Electronic Nicotine Delivery Systems , Humans , Animals , Respiratory System/drug effects , Vaping/adverse effects
SUMMARY: In response to the threat posed by new variants of SARS-CoV-2 and the urgent need for effective treatments in the absence of vaccines, the aim of this study was to develop a rapid and cost-effective hyperimmune serum (HS) derived from sheep and assess its efficacy. The utilization of a halal-certified, easily maintained in certain geographic regions, easy-to-handle animal such as sheep could provide a viable alternative to the expensive option of horses. Sheep were immunized with a whole inactivated SARS-CoV- 2 antigen to produce HS, which was evaluated for neutralizing potency using the PRNT50 assay. K18-hACE2 transgenic mice (n=35) were divided into three groups: control, SARS-CoV-2 exposure through inhalation, and SARS-CoV-2 exposed mice treated with HS. HS efficacy was assessed through serum proinflammatory cytokine levels, qRT-PCR analysis, histopathological examination of lungs and hearts, and transmission electron microscopy. Purified HS exhibited significant neutralizing activity (1/24,576). The SARS-CoV-2+HS group showed lower levels of TNF-α, IL-10, and IL-6 (P<0.01) and relatively lower levels of MCP-1 compared to the SARS-CoV-2 group. HS prevented death, reduced viral RNA levels in the lungs and hearts, protected against severe interstitial pneumonia, preserved lung tissue integrity, and prevented myocyte damage, while the SARS-CoV-2 group exhibited viral presence in the lungs. This study successfully developed a sheep-derived HS against the entire SARS-CoV-2 virus, resulting in a significant reduction in infection severity, inflammation, and systemic cytokine production. The findings hold promise for treating severe COVID-19 cases, including emerging viral variants, and immunocompromised patients.
En respuesta a la amenaza que suponen las nuevas variantes del SARS-CoV-2 y la urgente necesidad de tratamientos eficaces en ausencia de vacunas, el objetivo de este estudio fue desarrollar un suero hiperinmune (HS) rápido y rentable derivado de ovejas. y evaluar su eficacia. La utilización de un animal con certificación halal, de fácil mantenimiento en determinadas regiones geográficas y de fácil manejo, como las ovejas, podría proporcionar una alternativa viable a la costosa opción de los caballos. Las ovejas fueron inmunizadas con un antígeno de SARS-CoV-2 completamente inactivado para producir HS, cuya potencia neutralizante se evaluó mediante el ensayo PRNT50. Los ratones transgénicos K18-hACE2 (n = 35) se dividieron en tres grupos: control, exposición al SARS-CoV-2 mediante inhalación y ratones expuestos al SARS-CoV-2 tratados con HS. La eficacia de HS se evaluó mediante niveles de citoquinas proinflamatorias en suero, análisis qRT-PCR, examen histopatológico de pulmones y corazones y microscopía electrónica de transmisión. El HS purificado exhibió una actividad neutralizante significativa (1/24,576). El grupo SARS-CoV-2+HS mostró niveles más bajos de TNF-α, IL-10 e IL-6 (P<0,01) y niveles relativamente más bajos de MCP-1 en comparación con el grupo SARS-CoV-2. HS evitó la muerte, redujo los niveles de ARN viral en los pulmones y el corazón, protegió contra la neumonía intersticial grave, preservó la integridad del tejido pulmonar y evitó el daño de los miocitos, mientras que el grupo SARS-CoV-2 exhibió presencia viral en los pulmones. Este estudio desarrolló con éxito un HS derivado de ovejas contra todo el virus SARS-CoV-2, lo que resultó en una reducción significativa de la gravedad de la infección, la inflamación y la producción sistémica de citocinas. Los hallazgos son prometedores para el tratamiento de casos graves de COVID- 19, incluidas las variantes virales emergentes y los pacientes inmunocomprometidos.
Animals , COVID-19/drug therapy , Immune Sera/administration & dosage , Respiratory System/drug effects , Respiratory System/ultrastructure , Sheep , Vaccines, Inactivated , Severe Acute Respiratory Syndrome/prevention & control , Microscopy, Electron, Transmission , Real-Time Polymerase Chain Reaction , Flow Cytometry , SARS-CoV-2/drug effects , COVID-19/immunology , COVID-19/prevention & control , Heart/drug effects , Horses , Immunotherapy/methods , Multiple Organ Failure/prevention & control , Myocardium/ultrastructure
In this study, the toxicity effects on circulatory system and respiratory system, and the acute toxicity test of recombinant neorudin (EPR-hirudin, EH) in cynomolgus monkeys were evaluated to provide reference information for clinical studies. Eighteen cynomolgus monkeys were randomly divided into three groups for single intravenous administration of 3, 30 mg/kg EH and normal saline, respectively. The changes of respiratory frequency, respiratory intensity, blood pressure and electrocardiogram before and after administration were recorded. In acute toxicity test, six cynomolgus monkeys were intravenously received EH at a single dose of 171, 257, 385, 578, 867 and 1300 mg/kg respectively. The vital signs, hematology, serum biochemistry, coagulation indexes and electrocardiogram indexes of the animals were determined before administration and on the 7th and 14th day after administration. As the results showed that there were no significant abnormal changes in respiratory frequency, respiratory intensity, blood pressure or electrocardiogram in cynomolgus monkeys after receiving EH at 3 mg/kg and 30 mg/kg, and there was no statistical difference between the treated groups and normal saline group. In the acute toxicity test, no significant abnormalities were observed in vital signs, hematology, serum biochemistry, coagulation indexes and electrocardiogram indexes of six cynomolgus monkeys at day 7 and 14 after EH administration. Furthermore, autopsies of all cynomolgus monkeys showed no abnormalities. The results of toxicokinetics showed that AUClast of the drug increased in proportion to the EH dose in the range of 171-578 mg/kg, and increased in over proportion to the EH dose in the range of 578-1300 mg/kg. The variation of Cmax was basically consistent with AUClast. In a sum, A single intravenous injection of 3 and 30 mg/kg of EH did not affect the circulatory system and respiratory system in cynomolgus monkeys and the maximum tolerated dose of EH in cynomolgus monkey is over 1300 mg/kg (equivalent to 619-1300 times of the proposed clinical equivalent dose).
Cardiovascular System , Hirudins , Respiratory System , Toxicity Tests, Acute , Animals , Cardiovascular System/drug effects , Dose-Response Relationship, Drug , Hirudins/administration & dosage , Hirudins/toxicity , Infusions, Intravenous , Injections, Intravenous , Macaca fascicularis , Respiratory System/drug effects , Saline Solution/administration & dosage
SUMMARY: A great deal of attention of air pollution on respiratory health is increasing, particularly in relation to haze days. It is that exposure to cigarette smoke augments the toxicity of common air contaminants, thereby increasing the complexity of respiratory diseases. Although there are various mechanisms involved to respiratory diseases caused or worsen by cigarette smoking, in which the role of AQPs in the lung with regard to fluid homeostasis still remains elusive. In this paper, we copied the rat models based on smoke generator, and investigated the morphological changes of mucosa and related functions depending on the balance of lining liquid of alveoli via AQPs expression. Compared with normal group, weak labelling of AQP1 and AQP5 protein abundance were clearly detected in the corresponding part of smoke exposure groups compared with normal group. Hence, it is suggested that the contribution of AQPs in the lung is diminished, thereby causing perturbed balancing between resorptive and secretory fluid homeostasis under cigarette smoking.
Cada vez se presta más atención a la contaminación del aire en la salud respiratoria, particularmente, en relación con los días de neblina. En consecuencia la exposición al humo del cigarrillo aumenta la toxicidad de los contaminantes comunes del aire, lo que además aumenta la complejidad de las enfermedades respiratorias. Aunque existen varios mecanismos involucrados en las enfermedades respiratorias causadas o empeoradas por el tabaquismo, en las que el papel de las AQP en el pulmón respecto a la homeostasis de líquidos sigue siendo difícil de alcanzar. En este artículo, copiamos los modelos de rata basados en el generador de humo e investigamos los cambios morfológicos de la mucosa y las funciones relacionadas según el equilibrio del líquido de revestimiento de los alvéolos a través de la expresión de AQP. En comparación con el grupo normal, se detectó claramente un etiquetado débil de la abundancia de proteínas AQP1 y AQP5 en la parte correspondiente de los grupos de exposición al humo en comparación con el grupo control. Por lo tanto, se sugiere que la contribución de las AQP en el pulmón está disminuida, provocando así un equilibrio perturbado entre la homeostasis del líquido secretor y de reabsorción bajo el hábito de fumar cigarrillos.
Animals , Rats , Respiratory System/pathology , Cigarette Smoking/adverse effects , Respiratory System/drug effects , Body Fluids/metabolism , Immunohistochemistry , Microscopy, Electron , Rats, Sprague-Dawley , Aquaporins/metabolism , Homeostasis , Lung/drug effects , Lung/pathology
Currently, the whole world is facing a life-threatening novel coronavirus 2019 (COVID-19) pandemic. Natural products are well-known for their potential role against viral disease, and some anti-viral agents have been developed to combat these diseases. Herein, the authors investigated the possible effects of this Holy plant Nigella sativa L. (NS), against coronavirus, using evidence-based and mechanistic approaches to conclude the immune-boosting and alleviation of respiratory systemeffects of NS. The pharmacological studies established a prominent role in treating various respiratory, immune systems, cardiovascular, skin, and gastrointestinal disorders. Literature supported the significant anti-viral role and showed an inhibitory role for NS against MHV-A59 CoV (mouse-hepatitis virusA59) infected Hela, i.e., HeLaCEACAM1a (HeLa-epithelial carcinoembryonic antigen-related cell adhesion molecule 1a) cell. NS is a safe herbal product or dietary supplement and could be an effective and affordable community adjuvant treatment for coronavirus in the current scenario.
Actualmente, el mundo entero se enfrenta a una pandemia del nuevo coronavirus 2019 (COVID-19) que amenaza la vida. Los productos naturales son bien conocidos por su papel potencial contra las enfermedades virales, y se han desarrollado algunos agentes antivirales para combatir estas enfermedades. En este documento, los autores investigaron los posibles efectos de esta planta sagrada Nigella sativa L. (NS), contra el coronavirus, utilizando enfoques mecanicistas y basados en la evidencia para concluir el refuerzo inmunológico y el alivio de los efectos del SN en el sistema respiratorio. Los estudios farmacológicos establecieron un papel destacado en el tratamiento de diversos trastornos respiratorios, del sistema inmunológico, cardiovasculares, cutáneos y gastrointestinales. La literatura apoyó el importante papel antivírico y mostró un papel inhibidor de NS contra células Hela infectadas con MHV-A59 CoV (virus de la hepatitis de ratón-A59), es decir, HeLaCEACAM1a (molécula de adhesión celular 1a relacionada con el antígeno carcinoembrionario epitelial de HeLa). NS es un producto a base de hierbas o un suplemento dietético seguro y podría ser un tratamiento adyuvante comunitario eficaz y asequible para el coronavirus en el escenario actual.
Humans , Antiviral Agents/pharmacology , Plant Extracts/pharmacology , Nigella sativa/chemistry , COVID-19/drug therapy , Antiviral Agents/immunology , Respiratory System/drug effects , Respiratory System/immunology , Plant Extracts/immunology , Anti-Asthmatic Agents , COVID-19/immunology , Immune System/drug effects
Repurposing of the anthelminthic drug niclosamide was proposed as an effective treatment for inflammatory airway diseases such as asthma, cystic fibrosis, and chronic obstructive pulmonary disease. Niclosamide may also be effective for the treatment of viral respiratory infections, such as SARS-CoV-2, respiratory syncytial virus, and influenza. While systemic application of niclosamide may lead to unwanted side effects, local administration via aerosol may circumvent these problems, particularly when the drug is encapsulated into small polyethylene glycol (PEG) hydrospheres. In the present study, we examined whether PEG-encapsulated niclosamide inhibits the production of mucus and affects the pro-inflammatory mediator CLCA1 in mouse airways in vivo, while effects on mucociliary clearance were assessed in excised mouse tracheas. The potential of encapsulated niclosamide to inhibit TMEM16A whole-cell Cl- currents and intracellular Ca2+ signalling was assessed in airway epithelial cells in vitro. We achieved encapsulation of niclosamide in PEG-microspheres and PEG-nanospheres (Niclo-spheres). When applied to asthmatic mice via intratracheal instillation, Niclo-spheres strongly attenuated overproduction of mucus, inhibited secretion of the major proinflammatory mediator CLCA1, and improved mucociliary clearance in tracheas ex vivo. These effects were comparable for niclosamide encapsulated in PEG-nanospheres and PEG-microspheres. Niclo-spheres inhibited the Ca2+ activated Cl- channel TMEM16A and attenuated mucus production in CFBE and Calu-3 human airway epithelial cells. Both inhibitory effects were explained by a pronounced inhibition of intracellular Ca2+ signals. The data indicate that poorly dissolvable compounds such as niclosamide can be encapsulated in PEG-microspheres/nanospheres and deposited locally on the airway epithelium as encapsulated drugs, which may be advantageous over systemic application.
Niclosamide/administration & dosage , Pneumonia/drug therapy , Respiratory System/drug effects , Animals , Asthma/drug therapy , Asthma/metabolism , Asthma/pathology , COVID-19/complications , Cells, Cultured , Disease Models, Animal , Drug Carriers/chemistry , Drug Compounding , Humans , Hydrogels/chemistry , Instillation, Drug , Mice , Microspheres , Mucus/drug effects , Mucus/metabolism , Nanospheres/administration & dosage , Nanospheres/chemistry , Niclosamide/chemistry , Niclosamide/pharmacokinetics , Pneumonia/pathology , Polyethylene Glycols/chemistry , Respiratory Mucosa/drug effects , Respiratory Mucosa/metabolism , Respiratory System/metabolism , SARS-CoV-2/drug effects , SARS-CoV-2/physiology , Trachea , COVID-19 Drug Treatment
Asthma is a respiratory disease with complex pathogenesis. Sterol-responsive element-binding proteins 2 (SREBP2) was found to bind to promoter sequences of ABCA1 to suppress ABCA1 promoter activity. This study aimed to explore the expression level of SREBP2 and ATP-binding cassette transporter A1 (ABCA1), and their effects on the development of airway smooth muscle cells (ASMCs) in asthma. ASMCs were treated with different concentrations of TGF-ß1 (0, 0.5, 1, 5 and 10 ng/mL). Short hairpin SREBP2 (shSREBP2), SREBP2, shABCA1 or ABCA1 were transfected into ASMCs. Cell viability, proliferation, apoptosis, migration, and the expression of SREBP2, ABCA1 and related pathway proteins were detected by MTT assay, Brdu staining, flow cytometer, Transwell assay, qRT-PCR, and Western blotting, respectively. The results showed that TGF-ß1 increased the viability, proliferation, migration and inhibited apoptosis in ASMCs. Moreover, TGF-ß1 also decreased the expression of ABCA1, cleaved caspase-3, cleaved PARP, E-cadherin, and increased the expression of vimentin, TLR2, p-p65 and NFATc1. SREBP2 knockdown alleviated these TGF-ß1-induced changes. SREBP2 overexpression inhibited ABCA1 expression and apoptosis, and promoted cell migration and the expression of TLR2, p-p65, NFATc1 in ASMCs. ABCA1 overexpression alleviated these SREBP2-induced promoting and inhibition effects. In conclusion, SREBP2 activates TLR2/NF-κB/NFATc1 regulatory network and promotes TGF-ß1-induced cell movement through inhibiting ABCA1 expression.
Myocytes, Smooth Muscle , Sterol Regulatory Element Binding Protein 2/physiology , Transforming Growth Factor beta1/pharmacology , ATP Binding Cassette Transporter 1/genetics , ATP Binding Cassette Transporter 1/metabolism , Apoptosis/drug effects , Apoptosis/genetics , Cell Movement/drug effects , Cell Movement/genetics , Cell Proliferation/drug effects , Cell Proliferation/genetics , Cell Survival/drug effects , Cell Survival/genetics , Cells, Cultured , Humans , Myocytes, Smooth Muscle/drug effects , Myocytes, Smooth Muscle/physiology , NF-kappa B/genetics , NF-kappa B/metabolism , NFATC Transcription Factors/genetics , NFATC Transcription Factors/metabolism , Respiratory Mucosa/cytology , Respiratory Mucosa/drug effects , Respiratory Mucosa/metabolism , Respiratory System/cytology , Respiratory System/drug effects , Respiratory System/metabolism , Signal Transduction/drug effects , Signal Transduction/genetics , Toll-Like Receptor 2/genetics , Toll-Like Receptor 2/metabolism
While a considerable body of literature has characterized the clinical features induced by organophosphate pesticides, the field lacks scrutiny into cardio-respiratory changes in different phases of poisoning. Herein, we evaluated the impact of chlorpyrifos (CPF) and its active metabolite chlorpyrifos-oxon (CPO) on the cardiorespiratory system during acute and subacute phases of poisoning using an in situ experimental rodent model. CPF (30 mg/kg) was injected intraperitoneally to rats beforehand (24 h) whereas CPO (15 mg/kg) was added into the perfusate reservoir to evaluate the effects on the motor outputs throughout the three phases of the respiratory cycle: inspiration, post-inspiration and late expiration. Phrenic, recurrent laryngeal (RLN) and thoracic sympathetic nerve activity (tSNA) were recorded. Heart rate was derived from the electrocardiogram (ECG) and the baro- and chemo-reflexes tested. CPF and CPO led to a time-dependent change in cardiorespiratory motor outputs. In the acute phase, the CPO induced bradypnea, transiently reduced the inspiratory time (TI), and increased the amplitude of phrenic. Post-inspiratory (PI) discharge recorded from the RLN was progressively reduced while tSNA was increased. CPO significantly depressed the chemoreflex but had no effect on baroreflex. During subacute phase, CPF prolongated TI with no effect on respiratory rate. Both the RLN PI discharge, the chemoreflex and the baroreflex sympathetic gain were reduced. In addition, both CPF and CPO shifted the cardiac sympatho-vagal balance towards sympathetic dominance. Our data show that different phases of poisoning are associated with specific changes in the cardio-respiratory system and might therefore demand distinct approaches by health care providers.
Baroreflex/drug effects , Chlorpyrifos/adverse effects , Heart Rate/drug effects , Heart/drug effects , Respiratory System/drug effects , Animals , Chlorpyrifos/analogs & derivatives , Cholinesterase Inhibitors/adverse effects , Insecticides/adverse effects , Male , Rats , Rats, Wistar , Respiratory Rate/drug effects
Exposure to spray cleaning products constitutes a potential risk for asthma induction. We set out to review whether substances in such products are potential inducers of asthma. We identified 101 spray cleaning products for professional use. Twenty-eight of their chemical substances were selected. We based the selection on (a) positive prediction for respiratory sensitisation in humans based on quantitative structure activity relationship (QSAR) in the Danish (Q)SAR Database, (b) positive QSAR prediction for severe skin irritation in rabbits and (c) knowledge on the substances' physico-chemical characteristics and toxicity. Combining the findings in the literature and QSAR predictions, we could group substances into four classes: (1) some indication in humans for asthma induction: chloramine, benzalkonium chloride; (2) some indication in animals for asthma induction: ethylenediaminetetraacetic acid (EDTA), citric acid; (3) equivocal data: hypochlorite; (4) few or lacking data: nitriloacetic acid, monoethanolamine, 2-(2-aminoethoxy)ethanol, 2-diethylaminoethanol, alkyldimethylamin oxide, 1-aminopropan-2-ol, methylisothiazolinone, benzisothiazolinone and chlormethylisothiazolinone; three specific sulphonates and sulfamic acid, salicylic acid and its analogue sodium benzoate, propane-1,2-diol, glycerol, propylidynetrimethanol, lactic acid, disodium malate, morpholine, bronopol and benzyl alcohol. In conclusion, we identified an asthma induction potential for some of the substances. In addition, we identified major knowledge gaps for most substances. Thus, more data are needed to feed into a strategy of safe-by-design, where substances with potential for induction of asthma are avoided in future (spray) cleaning products. Moreover, we suggest that QSAR predictions can serve to prioritise substances that need further testing in various areas of toxicology.
Cosmetics/toxicity , Detergents/toxicity , Occupational Exposure/adverse effects , Respiratory System/drug effects , Soaps/toxicity , Animals , Asthma , Humans , Quantitative Structure-Activity Relationship , Respiratory System/physiopathology
No treatment-related effects at the low and mid doses were observed in gestation, viability and lactation indices, duration of gestation, parturition, sex ratio, maternal care, litter size, and early postnatal pup development consisting of mortality, clinical signs, anogenital distance, areola/nipple retention, T4 thyroid hormone levels, or macroscopic examination. However, the number of litters (N = 5) at the high dose was considered too low for toxicological evaluation. Thus, based on insufficient data at 120 mg/kg/day, the NOAEL for this study was considered to be 60 mg/kg/day (RIFM, 2020d).
Aldehydes/adverse effects , Cosmetics/chemistry , Environmental Exposure/adverse effects , Odorants/analysis , Perfume/adverse effects , Pregnancy Outcome , Safety , Academies and Institutes/standards , Aldehydes/analysis , Animals , Dermatitis, Photoallergic , Dermatitis, Phototoxic , Female , Household Products , Humans , Lactation/drug effects , Litter Size , Mutagenicity Tests , No-Observed-Adverse-Effect Level , Perfume/chemistry , Pregnancy , Registries , Respiratory System/drug effects , Risk Assessment , Skin/drug effects , Toxicity Tests
The existing information supports the use of this material as described in this safety assessment. 5,8-Methano-2H-1-benzopyran, 6(or 7)-ethylideneoctahydro-, [4aR,5S,8S,8aS(or 4aR,5R,8S,8aR)]-rel- was evaluated for genotoxicity, repeated dose toxicity, reproductive toxicity, local respiratory toxicity, phototoxicity/photoallergenicity, skin sensitization, and environmental safety. Data from read-across analog 5,8-methano-2H-1-benzopyran-2-one, 6- ethylideneoctahydro- (CAS # 69486-14-2) show that 5,8-methano-2H-1-benzopyran, 6(or 7)-ethylideneoctahydro-, [4aR,5S,8S,8aS(or 4aR,5R,8S,8aR)]-rel- is not expected to be genotoxic. The repeated dose, reproductive, and local respiratory toxicity endpoints were evaluated using the TTC for a Cramer Class III material, and the exposure to 5,8-methano-2H-1-benzopyran, 6(or 7)-ethylideneoctahydro-, [4aR,5S,8S,8aS(or 4aR,5R,8S,8aR)]-rel- is below the TTC (0.0015 mg/kg/day, 0.0015 mg/kg/day, and 0.47 mg/day, respectively). Data provided 5,8-methano-2H-1-benzopyran, 6(or 7)-ethylideneoctahydro-, [4aR,5S,8S,8aS(or 4aR,5R,8S,8aR)]-rel- a NESIL of 8200 µg/cm2 for the skin sensitization endpoint. The phototoxicity/photoallergenicity endpoints were evaluated based on human study data and UV/Vis spectra; 5,8-methano-2H-1-benzopyran, 6(or 7)-ethylideneoctahydro-, [4aR,5S,8S,8aS(or 4aR,5R,8S,8aR)]-rel- is not expected to be phototoxic/photoallergenic. The environmental endpoints were evaluated; 5,8-methano-2H-1-benzopyran, 6(or 7)-ethylideneoctahydro-, [4aR,5S,8S,8aS(or 4aR,5R,8S,8aR)]-rel- was found not to be PBT as per the IFRA Environmental Standards, and its risk quotients, based on its current volume of use in Europe and North America (i.e., PEC/PNEC), are <1.
Benzopyrans/toxicity , Cosmetics/chemistry , Environmental Exposure/adverse effects , Odorants/analysis , Perfume/toxicity , Safety , Academies and Institutes/standards , Animals , Benzopyrans/analysis , Dermatitis, Photoallergic , Dermatitis, Phototoxic , Environmental Pollutants/analysis , Environmental Pollutants/toxicity , Europe , Household Products , Humans , Mutagenicity Tests , North America , Perfume/chemistry , Registries , Reproduction/drug effects , Respiratory System/drug effects , Risk Assessment , Skin/drug effects , Toxicity Tests
Respiratory system injury is the main cause of mortality for nitrogen mustard (NM)-induced damage. Previous studies indicate that reactive oxygen species (ROS) participates in NM-mediated respiratory injuries, but the detailed mechanism is not quite clear. Human bronchial epithelial cell lines 16HBE and BEAS-2B were treated with HN2, a type of NM. In detail, it was shown that HN2 treatment induced impaired cell viability, excessive mitochondrial ROS production and enhanced cellular apoptosis in bronchial epithelial cells. Moreover, impaired Sirt3/SOD2 axis was observed upon HN2 treatment, with decreased Sirt3 and increased acetylated SOD2 expression levels. Sirt3 overexpression partially ameliorated HN2-induced cell injury. Meanwhile, vitamin D3 treatment partially attenuated HN2-induced apoptosis and improved the mitochondrial functions upon HN2 intervention. In addition, HN2 exposure decreased VDR expression, thus inhibiting the Nrf2 phosphorylation and Sirt3 activation. Inhibition of Nrf2 or Sirt3 could decrease the protective effects of vitamin D3 and enhance mitochondrial ROS production via modulating mitochondrial redox balance. In conclusion, impaired VDR/Nrf2/Sirt3 axis contributed to NM-induced apoptosis, while vitamin D3 supplementation provides protective effects via the activation of VDR and the improvement of mitochondrial functions. This study provides novel mechanism and strategy for NM exposure-induced pulmonary injuries.
Apoptosis/drug effects , Bronchi/drug effects , Cholecalciferol/pharmacology , Epithelial Cells/drug effects , Nitrogen Mustard Compounds/toxicity , Protective Agents/pharmacology , Respiratory System/drug effects , Cells, Cultured/drug effects , Humans , Respiratory System/physiopathology
The following paper presents the method of determination of the percolation threshold in cement composites with expanded graphite by impedance spectroscopy. Most of the applications of cement composites with conductive additives require exceeding the percolation threshold. The ionic conductivity of cement matrix below the percolation threshold has a major impact on the conductivity of the composite, as a result, it significantly hinders the exploitation of these composites. The electric properties of cement composites with expanded graphite were evaluated by DC measurements and impedance spectroscopy (IS). Based on Nyquist plots, two equivalent circuits were adopted for the composites. Next, the values of capacitance and inductance of cement composites with expanded graphite were calculated from the fitted equivalent circuits. The analysis of the results shows that the percolation threshold occurs when the reactance of the composite changes from captative to inductive. Comparison between the values of percolation threshold obtained from DC measurements and IS shows that the method is effective for cement composites with conductive additives.
Cosmetics/chemistry , Environmental Exposure/adverse effects , Formates/toxicity , Odorants/analysis , Perfume/toxicity , Safety , Academies and Institutes/standards , Animals , Dermatitis, Photoallergic , Dermatitis, Phototoxic , Electric Conductivity , Female , Formates/analysis , Graphite , Household Products/toxicity , Humans , Male , Mutagenicity Tests , Perfume/chemistry , Registries , Reproduction/drug effects , Respiratory System/drug effects , Risk Assessment , Skin/drug effects , Toxicity Tests
Respiratory irritation is an important human health endpoint in chemical risk assessment. There are two established modes of action of respiratory irritation, 1) sensory irritation mediated by the interaction with sensory neurons, potentially stimulating trigeminal nerve, and 2) direct tissue irritation. The aim of our research was to, develop a QSAR method to predict human respiratory irritants, and to potentially reduce the reliance on animal testing for the identification of respiratory irritants. Compounds are classified as irritating based on combined evidence from different types of toxicological data, including inhalation studies with acute and repeated exposure. The curated project database comprised 1997 organic substances, 1553 being classified as irritating and 444 as non-irritating. A comparison of machine learning approaches, including Logistic Regression (LR), Random Forests (RFs), and Gradient Boosted Decision Trees (GBTs), showed, the best classification was obtained by GBTs. The LR model resulted in an area under the curve (AUC) of 0.65, while the optimal performance for both RFs and GBTs gives an AUC of 0.71. In addition to the classification and the information on the applicability domain, the web-based tool provides a list of structurally similar analogues together with their experimental data to facilitate expert review for read-across purposes.
Irritants/chemistry , Machine Learning , Quantitative Structure-Activity Relationship , Respiratory System/drug effects , Administration, Inhalation , Animal Testing Alternatives/methods , Risk Assessment
The airway epithelium is a dynamic tissue that undergoes slow but constant renewal. Dysregulation of airway epithelial function related to cigarette smoke exposure plays an important role in the pathophysiology of COPD. Oct4 is a transcription factor responsible for maintaining cellular self-renewal and regeneration, and CD146 and CD105/Endoglin are adhesion molecules involved in cell proliferation, differentiation, epithelial-mesenchymal-transition and tissue remodeling. Bronchial biopsy specimens (BBs) were obtained from 7 healthy controls (HC) and 10 COPD and subjected to paraffin embedding; BBs from HC were also used for epithelial cell expansion and pHBEC/ALI (air-liquid interface) culture. pHBEC/ALI were exposed to cigarette smoke extract (CSE) for 7, 14 and 21 days. In BBs, Oct4, CD146 and CD105 were evaluated by immunohistochemistry. In pHBEC/ALI, the expression of Oct4, CD146, CD105 and acetyl-αtubulin was evaluated by Western Blot, MUC5AC and IL-8 measurements by ELISA. The Oct4 epithelial immunoreactivity was lower in COPD than in HC, whilst CD146 and CD105 expression was higher in COPD than in HC. In pHBEC/ALI, Transepithelial Electrical Resistance values, measured over 7 to 21 days of differentiation, decreased by 18% (2.5% CSE) and 29% (5% CSE) compared to untreated samples. Oct4 and acetyl-αtubulin were induced after one-week differentiation and downregulated by CSE in reconstituted epithelium; CD146, CD105, MUC5AC and IL-8 were increased by CSE. Oct4 de-regulation and CD146 and CD105 overexpression, induced by cigarette smoke exposure, might play a role in airway epithelial dysfunction by causing changes in self-renewal and mesenchymal transition mechanisms, leading to alteration of epithelium homeostasis and abnormal tissue remodeling involved in progression of COPD.
Cigarette Smoking/adverse effects , Endoglin/metabolism , Epithelial-Mesenchymal Transition , Octamer Transcription Factor-3/metabolism , Pulmonary Disease, Chronic Obstructive/pathology , Respiratory System/pathology , Adult , Aged , CD146 Antigen/genetics , CD146 Antigen/metabolism , Case-Control Studies , Cell Differentiation , Endoglin/genetics , Female , Humans , Male , Middle Aged , Octamer Transcription Factor-3/genetics , Pulmonary Disease, Chronic Obstructive/chemically induced , Pulmonary Disease, Chronic Obstructive/genetics , Pulmonary Disease, Chronic Obstructive/metabolism , Respiratory System/drug effects , Respiratory System/metabolism
The existing information supports the use of this material as described in this safety assessment. ß-Caryophyllene was evaluated for genotoxicity, repeated dose toxicity, reproductive toxicity, local respiratory toxicity, phototoxicity/photoallergenicity, skin sensitization, and environmental safety. Data show that ß-caryophyllene is not genotoxic. Data on ß-caryophyllene provided a calculated Margin of Exposure (MOE) > 100 for the repeated dose toxicity and fertility endpoints. The developmental and local respiratory toxicity endpoints were evaluated using the Threshold of Toxicological Concern (TTC) for a Cramer Class I material, and the exposure to ß-caryophyllene is below the TTC (0.03 mg/kg/day and 1.4 mg/day, respectively. Data show that there are no safety concerns for ß-caryophyllene for skin sensitization under the current declared levels of use. The phototoxicity/photoallergenicity endpoints were evaluated based on data and ultraviolet/visible (UV/Vis) spectra; ß-caryophyllene is not expected to be phototoxic/photoallergenic. The environmental endpoints were evaluated; ß-caryophyllene was found not to be Persistent, Bioaccumulative, and Toxic (PBT) as per the International Fragrance Association (IFRA) Environmental Standards, and its risk quotients, based on its current volume of use in Europe and North America (i.e., Predicted Environmental Concentration/Predicted No Effect Concentration [PEC/PNEC]), are <1.
Environmental Exposure/adverse effects , Odorants/analysis , Perfume/toxicity , Plants, Edible/chemistry , Polycyclic Sesquiterpenes/toxicity , Safety , Academies and Institutes/standards , Animals , Dermatitis, Photoallergic , Dermatitis, Phototoxic , Endpoint Determination , Europe , Fertility/drug effects , Humans , Mutagenicity Tests , North America , Perfume/chemistry , Polycyclic Sesquiterpenes/analysis , Quantitative Structure-Activity Relationship , Registries , Reproduction/drug effects , Respiratory System/drug effects , Risk Assessment , Skin/drug effects , Toxicity Tests
The existing information supports the use of this material as described in this safety assessment. Tetrahydro-6-(3-pentenyl)-2H-pyran-2-one was evaluated for genotoxicity, repeated dose toxicity, reproductive toxicity, local respiratory toxicity, phototoxicity/photoallergenicity, skin sensitization, and environmental safety. Data show that tetrahydro-6-(3-pentenyl)-2H-pyran-2-one is not genotoxic. The repeated dose, reproductive, and local respiratory toxicity endpoints were evaluated using the Threshold of Toxicological Concern (TTC) for a Cramer Class II material, and the exposure to tetrahydro-6-(3-pentenyl)-2H-pyran-2-one is below the TTC (0.009 mg/kg/day, 0.009 mg/kg/day, and 0.47 mg/day, respectively). Data and read-across to 5-hydroxy-7-decenoic acid δ-lactone (CAS # 25,524-95-2) show that there are no safety concerns for tetrahydro-6-(3-pentenyl)-2H-pyran-2-one for skin sensitization under the current declared levels of use. The phototoxicity/photoallergenicity endpoints were evaluated based on data and ultraviolet/visible (UV/Vis) spectra; tetrahydro-6-(3-pentenyl)-2H-pyran-2-one is not expected to be phototoxic/photoallergenic. The environmental endpoints were evaluated; tetrahydro-6-(3-pentenyl)-2H-pyran-2-one was found not to be Persistent, Bioaccumulative, and Toxic (PBT) as per the International Fragrance Association (IFRA) Environmental Standards, and its risk quotients, based on its current volume of use in Europe and North America (i.e., Predicted Environmental Concentration/Predicted No Effect Concentration [PEC/PNEC]), are <1.
Environmental Exposure/adverse effects , Odorants/analysis , Perfume/toxicity , Pyrans/toxicity , Safety , Academies and Institutes/standards , Animals , Dermatitis, Photoallergic , Dermatitis, Phototoxic , Europe , Humans , Mutagenicity Tests , North America , Perfume/chemistry , Pyrans/analysis , Registries , Reproduction/drug effects , Respiratory System/drug effects , Risk Assessment , Skin/drug effects , Toxicity Tests
The existing information supports the use of this material as described in this safety assessment. Phenethyl phenylacetate was evaluated for genotoxicity, repeated dose toxicity, reproductive toxicity, local respiratory toxicity, phototoxicity/photoallergenicity, skin sensitization, and environmental safety. Data show that phenethyl phenylacetate is not genotoxic. Data provide a calculated MOE >100 for the repeated dose toxicity endpoint. Data on read-across analog benzyl benzoate (CAS # 120-51-4) provide an MOE >100 for the developmental toxicity endpoint. The fertility and local respiratory toxicity endpoints were evaluated using the TTC for a Cramer Class I material, and the exposure to phenethyl phenylacetate is below the TTC (0.03 mg/kg/day, and 1.4 mg/day, respectively). Data from analog benzyl phenylacetate (CAS # 102-16-9) show that there are no safety concerns for phenethyl phenylacetate for skin sensitization under the current declared levels of use. The phototoxicity/photoallergenicity endpoints were evaluated based on UV/Vis spectra; phenethyl phenylacetate is not expected to be phototoxic/photoallergenic. The environmental endpoints were evaluated; phenethyl phenylacetate was found not to be PBT as per the IFRA Environmental Standards and its risk quotients, based on its current volume of use in Europe and North America (i.e., PEC/PNEC), are <1.
Acetates/toxicity , Environmental Exposure/adverse effects , Odorants/analysis , Perfume/toxicity , Phenols/toxicity , Phenylacetates/toxicity , Safety , Academies and Institutes/standards , Acetates/analysis , Animals , Dermatitis, Photoallergic , Dermatitis, Phototoxic , Endpoint Determination , Europe , Fertility/drug effects , Humans , Mutagenicity Tests , North America , Perfume/chemistry , Phenols/analysis , Phenylacetates/analysis , Registries , Reproduction/drug effects , Respiratory System/drug effects , Risk Assessment , Skin/drug effects , Toxicity Tests
