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BACKGROUND: Alveolar macrophages (AMs) have been predicted to affect the pulmonary clearance of nanomaterials; however, their qualitative and quantitative roles are poorly understood. In this study, carbon black nanoparticles (CBNPs) were instilled into the lungs of Wistar rats at 30, 100, and 300 µg/rat. The concentrations of particles in organs, including the lung, lung-associated lymph nodes (LALN), liver, spleen, and kidney, were evaluated at days 0 (immediately after instillation), 1, 7, 28, 60, and 90 post-instillation. RESULTS: The results indicated a multimodal pulmonary clearance pattern for CBNPs: slow clearance until day 28, fast clearance from days 28 to 60, and slow clearance from days 60 to 90. To determine the mechanism of this unique clearance pattern, CBNPs were instilled into AM-depleted rats using clodronate liposomes (CLO). At 28 days after instillation, the CBNP levels in the lungs treated with CLO showed about 31% higher reduction than in normal rats. In addition, the concentration of CBNPs in LALN treated with CLO significantly increased on day 28, whereas in normal rats, no detectable levels were observed. CONCLUSIONS: This result highlights that the prolonged retention of poorly soluble NPs in the lung until day 28 is mediated by the phagocytosis of AMs, and the fast clearance between days 28-60 is due to the turnover time of AMs, estimated around 1-2 months after birth. Similarly, new generations of AMs mediate the slow phase between days 60 and 90. However, further studies are needed to understand the multimodal clearance mechanism and the modulation of pulmonary clearance of poorly soluble NPs.
Assuntos
Pulmão , Macrófagos Alveolares , Nanopartículas , Ratos Wistar , Fuligem , Animais , Macrófagos Alveolares/metabolismo , Macrófagos Alveolares/efeitos dos fármacos , Fuligem/toxicidade , Fuligem/química , Pulmão/metabolismo , Pulmão/efeitos dos fármacos , Masculino , Distribuição Tecidual , Ratos , Tamanho da Partícula , Ácido Clodrônico/administração & dosagem , Taxa de Depuração MetabólicaRESUMO
BACKGROUND: Polypropylene (PP) is used in various products such as disposable containers, spoons, and automobile parts. The disposable masks used for COVID-19 prevention mainly comprise PP, and the disposal of such masks is concerning because of the potential environmental pollution. Recent reports have suggested that weathered PP microparticles can be inhaled, however, the inhalation toxicology of PP microparticles is poorly understood. RESULTS: Inflammatory cell numbers, reactive oxygen species (ROS) production, and the levels of inflammatory cytokines and chemokines in PP-instilled mice (2.5 or 5 mg/kg) increased significantly compared to with those in the control. Histopathological analysis of the lung tissue of PP-stimulated mice revealed lung injuries, including the infiltration of inflammatory cells into the perivascular/parenchymal space, alveolar epithelial hyperplasia, and foamy macrophage aggregates. The in vitro study indicated that PP stimulation causes mitochondrial dysfunction including mitochondrial depolarization and decreased adenosine triphosphate (ATP) levels. PP stimulation led to cytotoxicity, ROS production, increase of inflammatory cytokines, and cell deaths in A549 cells. The results showed that PP stimulation increased the p-p38 and p-NF-κB protein levels both in vivo and in vitro, while p-ERK and p-JNK remained unchanged. Interestingly, the cytotoxicity that was induced by PP exposure was regulated by p38 and ROS inhibition in A549 cells. CONCLUSIONS: These results suggest that PP stimulation may contribute to inflammation pathogenesis via the p38 phosphorylation-mediated NF-κB pathway as a result of mitochondrial damage.
Assuntos
Microplásticos , Pneumonia , Polipropilenos , Animais , Camundongos , Citocinas/metabolismo , Inflamação/induzido quimicamente , Inflamação/metabolismo , Microplásticos/toxicidade , NF-kappa B/metabolismo , Pneumonia/induzido quimicamente , Polipropilenos/toxicidade , Espécies Reativas de Oxigênio/metabolismoRESUMO
To declare a shampoo toxicologically safe, one should evaluate the hazards posed by the inhalation of aerosols produced during its use. Herein, tap water was sprayed into a shampoo-filled plastic container to investigate the formation of shampoo aerosols and the possibility of their inhalation. The aerosols thus obtained had higher mass concentrations (geometric mean = 5779 µg m-3 (PM10) and 2249 µg m-3 (PM2.5)) than water aerosols (geometric mean = 927 µg m-3 (PM10) and 476 µg m-3 (PM2.5)). In particular, shampoo aerosol particles with an aerodynamic diameter of 2.5 µm, which can penetrate the alveoli when inhaled, had the highest mass concentration (geometric mean = 2000 µg m-3). The volatile organic compounds contained in shampoo aerosols featured alcohol and ether groups attached to dodecane and tetradecane backbones; these compounds were generated by the thermal decomposition of surfactants (i.e., lauryl and laureth sulfates) during instrumental analysis. The acquired data suggest that inhalation exposure and chronic inhalation toxicity evaluations should be performed for various shampoo usage conditions to ensure inhalation safety.
Assuntos
Poluentes Atmosféricos , Compostos Orgânicos Voláteis , Aerossóis/análise , Poluentes Atmosféricos/análise , Monitoramento Ambiental , Exposição por Inalação , Tamanho da Partícula , Material Particulado/análise , SulfatosRESUMO
A public health crisis in the form of a significant incidence of fatal pulmonary disease caused by repeated use of humidifier disinfectants containing polyhexamethylene guanidine phosphate (PHMG) recently arose in Korea. Although the mechanisms of pulmonary fibrosis following respiratory exposure to PHMG are well described, distant-organ effect has not been reported. In this study, we investigated whether intratracheal administration of PHMG affects liver pathophysiology and metabolism. Our PHMG mouse model showed a significant decrease in liver cholesterol level. An mRNA-seq analysis of liver samples revealed an alteration in the gene expression associated with cholesterol biosynthesis and metabolism to bile acids. The expression of genes involved in cholesterol synthesis was decreased in a real-time PCR analysis. To our surprise, we found that the coordinate regulation of cholesterol and bile acid homeostasis was completely disrupted. Despite the decreased cholesterol synthesis and low bile acid levels, the farnesoid X receptor/small heterodimer partner pathway, which controls negative feedback of bile acid synthesis, was activated in PHMG mice. As a consequence, gene expression of Cyp7a1 and Cyp7b1, the rate-limiting enzymes of the classical and alternative pathways of bile acid synthesis, was significantly downregulated. Notably, the changes in gene expression were corroborated by the hepatic concentrations of the bile acids. These results suggest that respiratory exposure to PHMG could cause cholestatic liver injury by disrupting the physiological regulation of hepatic cholesterol and bile acid homeostasis.
Assuntos
Ácidos e Sais Biliares , Colesterol , Camundongos , Animais , Ácidos e Sais Biliares/metabolismo , Colesterol/metabolismo , Fígado/metabolismo , HomeostaseRESUMO
Globally, plastics are used in various products. Concerns regarding the human body's exposure to plastics and environmental pollution have increased with increased plastic use. Microplastics can be detected in the atmosphere, leading to potential human health risks through inhalation; however, the toxic effects of microplastic inhalation are poorly understood. In this study, we examined the pulmonary toxicity of polystyrene (PS), polypropylene (PP), and polyvinyl chloride (PVC) in C57BL/6, BALB/c, and ICR mice strains. Mice were intratracheally instilled with 5 mg/kg of PS, PP, or PVC daily for two weeks. PS stimulation increased inflammatory cells in the bronchoalveolar lavage fluid (BALF) of C57BL/6 and ICR mice. Histopathological analysis of PS-instilled C57BL/6 and PP-instilled ICR mice showed inflammatory cell infiltration. PS increased the NLR family pyrin domain containing 3 (NLRP3) inflammasome components in the lung tissue of C57BL/6 and ICR mice, while PS-instilled BALB/c mice remained unchanged. PS stimulation increased inflammatory cytokines, including IL-1ß and IL-6, in BALF of C57BL/6 mice. PP-instilled ICR mice showed increased NLRP3, ASC, and Caspase-1 in the lung tissue compared to the control groups and increased IL-1ß levels in BALF. These results could provide baseline data for understanding the pulmonary toxicity of microplastic inhalation.
Assuntos
Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos , Microplásticos , Camundongos , Humanos , Animais , Cloreto de Polivinila/toxicidade , Poliestirenos/toxicidade , Plásticos , Polipropilenos/toxicidade , Proteína 3 que Contém Domínio de Pirina da Família NLR , Camundongos Endogâmicos ICR , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos BALB CRESUMO
Exposure to particulate matter (PM) is related to various respiratory diseases, and this affects the respiratory immune system. Alveolar macrophages (AMs), which are defenders against pathogens, play a key role in respiratory inflammation through cytokine production and cellular interactions. Coconut oil demonstrates antioxidant and anti-inflammatory properties, and it is consumed worldwide for improved health. However, reports on the protective effects of coconut oil on the PM-induced respiratory immune system, especially in AMs, are limited. In this study, we generated artificial PM (APM) with a diameter approximately of 30 nm by controlling the temperature, and compared its cytotoxicity with diesel exhaust particles (DEP). We also investigated the antioxidant and anti-inflammatory effects of coconut oil in APM− and DEP−stimulated AMs, and the underlying molecular mechanisms. Our results showed that APM and DEP had high cytotoxicity in a dose-dependent manner in AMs. In particular, APM or DEP at 100 µg/mL significantly decreased cell viability (p < 0.05) and significantly increased oxidative stress markers such as reactive oxygen species (p < 0.01); the GSSH/GSH ratio (p < 0.01); and cytokine production, such as tumor necrosis factor-α (p < 0.001), interleukin (IL)-1ß (p < 0.001), and IL-6 (p < 0.001). The expression of the genes for chemokine (C-X-C motif) ligand-1 (p < 0.05) and monocyte chemoattractant protein-1 (p < 0.001); and the proteins toll-like receptor (TLR) 4 (p < 0.01), mitogen-activated protein kinase (MAPK), and c-Jun N-terminal kinase (p < 0.001), p38 (p < 0.001); and extracellular receptor-activated kinase (p < 0.001), were also upregulated by PM. These parameters were reversed upon treatment with coconut oil in APM− or DEP−stimulated AMs. In conclusion, coconut oil can reduce APM− or DEP−induced inflammation by regulating the TLR4/MAPK pathway in AMs, and it may protect against adverse respiratory effects caused by PM exposure.
Assuntos
Macrófagos Alveolares , Material Particulado , Anti-Inflamatórios/farmacologia , Antioxidantes/farmacologia , Óleo de Coco , Humanos , Inflamação/induzido quimicamente , Inflamação/tratamento farmacológico , Inflamação/metabolismo , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Estresse Oxidativo , Material Particulado/metabolismo , Material Particulado/toxicidade , Emissões de VeículosRESUMO
This study evaluates the behavioral characteristics of components (methylisothiazolinone (MIT) and chloromethylisothiazolinone (CMIT)) contained in disinfectant solutions when they convert to liquid aerosols. The analytical method for MIT and CMIT quantitation was established and optimized using sorbent tube/thermal desorber-gas chromatography-mass spectrometry system; their behavioral characteristics are discussed using the quantitative results of these aerosols under different liquid aerosol generation conditions. MIT and CMIT showed different behavioral characteristics depending on the aerosol mass concentration and sampling time (sampling volume). When the disinfectant solution was initially aerosolized, MIT and CMIT were primarily collected on glass filter (MIT = 91.8 ± 10.6% and CMIT = 90.6 ± 5.18%), although when the generation and filter sampling volumes of the aerosols increased to 30 L, the relative proportions collected on the filter decreased (MIT = 79.0 ± 12.0% and CMIT = 39.7 ± 8.35%). Although MIT and CMIT had relatively high vapor pressure, in liquid aerosolized state, they primarily accumulated on the filter and exhibited particulate behavior. Their relative proportions in the aerosol were different from those in disinfectant solution. In the aerosol with mass concentration of ≤5 mg m-3, the relative proportion deviations of MIT and CMIT were large; when the mass concentration of the aerosol increased, their relative proportions constantly converged at a lower level than those in the disinfectant solution. Hence, it can be concluded that the behavioral characteristics and relative proportions need to be considered to perform the quantitative analysis of the liquid aerosols and evaluate various toxic effects using the quantitative data.
RESUMO
Polyhexamethylene guanidine phosphate (PHMG-p) was used as a humidifier disinfectant in Korea. PHMG induced severe pulmonary fibrosis in Koreans. The objective of this study was to elucidate mechanism of pulmonary toxicity caused by PHMG-p in rats using multi-omics analysis. Wistar rats were intratracheally instilled with PHMG-p by single (1.5 mg/kg) administration or 4-week (0.1 mg/kg, 2 times/week) repeated administration. Histopathologic examination was performed with hematoxylin and eosin staining. Alveolar macrophage aggregation and granulomatous inflammation were observed in rats treated with single dose of PHMG-p. Pulmonary fibrosis, chronic inflammation, bronchiol-alveolar fibrosis, and metaplasia of squamous cell were observed in repeated dose group. Next generation sequencing (NGS) was performed for transcriptome profiling after mRNA isolation from bronchiol-alveoli. Bronchiol-alveoli proteomic profiling was performed using an Orbitrap Q-exactive mass spectrometer. Serum and urinary metabolites were determined using 1H-NMR. Among 418 differentially expressed genes (DEGs) and 67 differentially expressed proteins (DEPs), changes of 16 mRNA levels were significantly correlated with changes of their protein levels in both single and repeated dose groups. Remarkable biological processes represented by both DEGs and DEPs were defense response, inflammatory response, response to stress, and immune response. Arginase 1 (Arg1) and lipocalin 2 (Lcn2) were identified to be major regulators for PHMG-p-induced pulmonary toxicity based on merged analysis using DEGs and DEPs. In metabolomics study, 52 metabolites (VIP > 0.5) were determined in serum and urine of single and repeated-dose groups. Glutamate and choline were selected as major metabolites. They were found to be major factors affecting inflammatory response in association with DEGs and DEPs. Arg1 and Lcn2 were suggested to be major gene and protein related to pulmonary damage by PHMG-p while serum or urinary glutamate and choline were endogenous metabolites related to pulmonary damage by PHMG-p.
Assuntos
Desinfetantes/toxicidade , Guanidinas/toxicidade , Lesão Pulmonar/induzido quimicamente , Animais , Biomarcadores/metabolismo , Biologia Computacional , Células Epiteliais , Perfilação da Expressão Gênica , Umidificadores , Pulmão , Lesão Pulmonar/veterinária , Masculino , Metabolômica , Proteômica , Alvéolos Pulmonares , Fibrose Pulmonar , Ratos , Ratos Wistar , República da Coreia , Testes de Toxicidade , TranscriptomaRESUMO
In 2011, a link between humidifier disinfectants and patients with idiopathic pulmonary fibrosis was identified in Korea, and Kathon was suggested as one of the causative agents. In this study, Kathon induced apoptotic cell death along with membrane damage at 24 h post-exposure. Additionally, on day 14 after a single instillation with Kathon, the total number of pulmonary cells and the levels of TNF-α, IL-5, IL-13, MIP-1α, and MCP-1α clearly increased in the lung of mice. The proportion of natural killer cells and eosinophils were significantly elevated in the spleen and the bloodstream, respectively, and the level of immunoglobulin (Ig) A, but not IgG, IgM, and IgE, dose-dependently increased. Therefore, we suggest that inhaled Kathon may induce eosinophilia-mediated disease in the lung by disrupting homeostasis of pulmonary surfactants. Considering that eosinophilia is closely related to cancer and fibrosis, further studies are needed to understand the relationship between them.
Assuntos
Desinfetantes/toxicidade , Eosinofilia/induzido quimicamente , Pulmão/efeitos dos fármacos , Surfactantes Pulmonares/metabolismo , Tiazóis/toxicidade , Animais , Apoptose/efeitos dos fármacos , Linhagem Celular , Citocinas/imunologia , Eosinofilia/sangue , Eosinofilia/imunologia , Eosinófilos/citologia , Humanos , Imunoglobulina A/sangue , Exposição por Inalação/efeitos adversos , Pulmão/imunologia , Pulmão/metabolismo , Pulmão/patologia , Masculino , Camundongos , Camundongos Endogâmicos ICRRESUMO
Currently available toxicity data on humidifier disinfectants are primarily limited to polyhexamethylene guanidine phosphate-induced lung fibrosis. We, therefore, investigated whether the sterilizer component Kathon, which is a mixture of chloromethylisothiazolinone and methylisothiazolinone, induces fibrotic lung injury following direct lung exposure in an animal model. Mice were intratracheally instilled with either the vehicle or Kathon. Differential cell counts, cytokine analysis, and histological analysis of lung tissue were then performed to characterize the injury features, and we investigated whether Kathon altered fibrosis-related gene expression in lung tissues via RNA-Seq and bioinformatics. Cell counting showed that Kathon exposure increased the proportion of macrophages, eosinophils, and neutrophils. Moreover, T helper 2 (Th2) cytokine levels in the bronchoalveolar lavage were significantly increased in the Kathon groups. Histopathological analysis revealed increased perivascular/alveolar inflammation, eosinophilic cells, mucous cell hyperplasia, and pulmonary fibrosis following Kathon exposure. Additionally, Kathon exposure modulated the expression of genes related to fibrotic inflammation, including the phosphatidylinositol 3-kinase (PI3K)/protein kinase B (AKT) signaling pathway, extracellular signal regulated kinase (ERK)1 and ERK2 cascade, extracellular matrix (ECM)-receptor interaction pathway, transforming growth factor beta receptor signaling pathway, cellular response to tumor necrosis factor, and collagen fibril organization. Our results suggest that Kathon exposure is associated with fibrotic lung injury via a Th2-dependent pathway and is thus a possible risk factor for fibrosis.
Assuntos
Desinfetantes/toxicidade , Eosinófilos/efeitos dos fármacos , Umidificadores , Fibrose Pulmonar/induzido quimicamente , Células Th2/efeitos dos fármacos , Animais , Asma/genética , Líquido da Lavagem Broncoalveolar , Citocinas/metabolismo , Eosinófilos/patologia , Regulação da Expressão Gênica/efeitos dos fármacos , Pulmão/efeitos dos fármacos , Pulmão/patologia , Masculino , Camundongos Endogâmicos C57BL , Tamanho do Órgão/efeitos dos fármacos , Fibrose Pulmonar/genética , Fibrose Pulmonar/patologia , Células Th2/patologia , Tiazóis/toxicidadeRESUMO
Diesel exhaust particulates (DEP) have adverse effects on the respiratory system. Endoplasmic reticulum (ER) abnormalities contribute to lung inflammation. However, the relationship between DEP exposure and ER stress in the respiratory immune system and especially the alveolar macrophages (AM) is poorly understood. Here, we examined ER stress and inflammatory responses using both in vivo and in vitro study. For in vivo study, mice were intratracheally instilled with 25, 50, and 100 µg DEP and in vitro AM were stimulated with DEP at 1, 2, and 3 mg/mL. DEP increased lung weight and the number of inflammatory cells, especially neutrophils, and inflammatory cytokines in bronchoalveolar lavage fluid of mice. DEP also increased the number of DEP-pigmented AM and ER stress markers including bound immunoglobulin protein (BiP) and CCAAT/enhancer binding protein-homologous protein (CHOP) were upregulated in the lungs of DEP-treated mice. In an in vitro study, DEP caused cell damage, increased intracellular reactive oxygen species, and upregulated inflammatory genes and ER stress-related BiP, CHOP, splicing X-box binding protein 1, and activating transcription factor 4 expressions in AM. Furthermore, DEP released the C-X-C Motif Chemokine Ligand 1 (CXCL1/KC) in AM. In conclusion, DEP may contribute to neutrophilic lung inflammation pathogenesis by modulating ER stress-mediated CXCL1/KC expression in AM.
Assuntos
Quimiocina CXCL1/metabolismo , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Pulmão/efeitos dos fármacos , Macrófagos Alveolares/efeitos dos fármacos , Neutrófilos/efeitos dos fármacos , Material Particulado/efeitos adversos , Pneumonia/induzido quimicamente , Animais , Líquido da Lavagem Broncoalveolar , Citocinas/metabolismo , Feminino , Pulmão/metabolismo , Macrófagos Alveolares/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Neutrófilos/metabolismo , Pneumonia/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Receptores de Antígenos de Linfócitos B/metabolismo , Fator de Transcrição CHOP/metabolismo , Regulação para Cima/efeitos dos fármacos , Regulação para Cima/ética , Emissões de VeículosRESUMO
INTRODUCTION: Polyhexamethylene guanidine phosphate (PHMG) has been used as a disinfectant and biocide, and was known to be harmless and non-toxic. However, in 2011, PHMG used as a humidifier disinfectant was reported to be associated with lung diseases, such as, fibrosis in the toxicant studies on pulmonary fibrosis by PHMG. However, no metabolomics study has been performed in PHMG-induced mouse models of pulmonary fibrosis. OBJECTIVES: We performed a metabolomic study to understand the biochemical events that occur in bleomycin (BLM)- and PHMG-induced mouse models of pulmonary fibrosis using gas chromatography-mass spectrometry (GC-MS), LC-tandem MS, and GC-tandem MS. RESULTS: The levels of 61 metabolites of 30 amino acids, 13 organic acids, 12 fatty acids, 5 polyamines, and oxidized glutathione were determined in the pulmonary tissues of mice with BLM- and PHMG-induced pulmonary fibrosis and in normal controls. Principal component analysis and partial least squares discriminant analysis used to compare level of these 61 metabolites in pulmonary tissues. Levels of metabolites were significantly different in the BLM and PHMG groups as compared with the control group. In particular, the BLM- and PHMG-induced pulmonary fibrosis models showed elevated collagen synthesis and oxidative stress and metabolic disturbance of TCA related organic acids including fumaric acid by NADPH oxidase. In addition, polyamine metabolism showed severe alteration in the PHMG group than that of the BLM group. CONCLUSION: This result suggests PHMG will be able to induce pulmonary fibrosis by arginine metabolism and NADPH oxidase signaling.
Assuntos
Bleomicina/metabolismo , Modelos Animais de Doenças , Guanidinas/metabolismo , Metabolômica , Fibrose Pulmonar/induzido quimicamente , Fibrose Pulmonar/metabolismo , Animais , Bleomicina/administração & dosagem , Bleomicina/análise , Cromatografia Gasosa , Cromatografia Líquida , Guanidinas/administração & dosagem , Guanidinas/análise , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Fibrose Pulmonar/patologia , Espectrometria de Massas em TandemRESUMO
Objective: Humidifier-disinfectant-induced lung injury is a new syndrome associated with a high mortality rate and characterized by severe hypersensitivity pneumonitis, acute interstitial pneumonia, or acute respiratory distress syndrome. Polyhexamethylene guanidine phosphate (PHMG-P), a guanidine-based antimicrobial agent, is a major component associated with severe lung injury. In-depth studies are needed to determine how PHMG-P affects pathogenesis at the molecular level. Therefore, in this study, we analyzed short-term (4 weeks) and long-term (10 weeks) PHMG-P-exposure-specific gene-expression patterns in rats to improve our understanding of time-dependent changes in fibrosis.Materials and methods: Gene-expression profiles were analyzed in rat lung tissues using DNA microarrays and bioinformatics tools.Results: Clustering analysis of gene-expression data showed different gene-alteration patterns in the short- and long-term exposure groups and higher sensitivity to gene-expression changes in the long-term exposure group than in the short-term exposure group. Supervised analysis revealed 34 short-term and 335 long-term exposure-specific genes, and functional analysis revealed that short-term exposure-specific genes were involved in PHMG-P-induced initial inflammatory responses, whereas long-term exposure-specific genes were involved in PHMG-P-related induction of chronic lung fibrosis.Conclusion: The results of transcriptomic analysis were consistent with lung histopathology results. These findings indicated that exposure-time-specific changes in gene expression closely reflected time-dependent pathological changes in PHMG-P-induced lung injury.
Assuntos
Desinfetantes/toxicidade , Guanidinas/toxicidade , Exposição por Inalação/efeitos adversos , Lesão Pulmonar/induzido quimicamente , Pulmão/efeitos dos fármacos , Transcriptoma/efeitos dos fármacos , Animais , Análise por Conglomerados , Relação Dose-Resposta a Droga , Feminino , Perfilação da Expressão Gênica , Exposição por Inalação/análise , Pulmão/patologia , Lesão Pulmonar/genética , Lesão Pulmonar/patologia , Masculino , Ratos , Ratos Sprague-Dawley , Fatores de TempoRESUMO
BACKGROUND: The respiratory system is exposed to various allergens via inhaled and intranasal routes. Murine models of allergic lung disease have been developed to clarify the mechanisms underlying inflammatory responses and evaluate the efficacy of novel therapeutics. However, there have been no comparative studies on differences in allergic phenotypes following inhaled vs. intranasal allergen challenge. In this study, we compared the asthmatic features of mice challenged via different routes following allergen sensitization and investigated the underlying mechanisms. METHODS: To establish ovalbumin (OVA)-induced allergic asthma models, BALB/c mice were sensitized to 20 µg OVA with 1 mg aluminum hydroxide by the intraperitoneal route and then challenged by inhalation or intranasal administration with 5% OVA for 3 consecutive days. Cellular changes and immunoglobulin (Ig) E levels in bronchoalveolar lavage fluid (BALF) and serum, respectively, were assessed. Histological changes in the lungs were examined by hematoxylin and eosin (H&E) and periodic acid Schiff (PAS) staining. Levels of T helper (Th)2 cytokines including interleukin (IL)-4, -5, and -13 in BALF and epithelial cytokines including IL-25 and -33 in BALF and lung tissues were measured by enzyme-linked immunosorbent assay and western blotting. Airway hyperresponsiveness (AHR) was evaluated by assessing airway resistance (Rrs) and elastance (E) via an invasive method. RESULTS: OVA-sensitized and challenged mice showed typical asthma features such as airway inflammation, elevated IgE level, and AHR regardless of the challenge route. However, H&E staining showed that inflammation of pulmonary vessels, alveolar ducts, and alveoli were enhanced by inhaled as compared to intranasal OVA challenge. PAS staining showed that intranasal OVA challenge induced severe mucus production accompanied by inflammation in bronchial regions. In addition, Th2 cytokine levels in BALF and AHR in lung were increased to a greater extent by inhalation than by intranasal administration of OVA. Epithelial cytokine expression, especially IL-25, was increased in the lungs of mice in the inhaled OVA challenge group. CONCLUSION: OVA-sensitized mice exhibit different pathophysiological patterns of asthma including expression of epithelial cell-derived cytokines depending on the OVA challenge route. Thus, some heterogeneous phenotypes of human asthma can be replicated by varying the mode of delivery after OVA sensitization.
Assuntos
Asma/classificação , Hiper-Reatividade Brônquica/imunologia , Interleucina-17/imunologia , Ovalbumina/administração & dosagem , Fenótipo , Linfócitos T/imunologia , Administração por Inalação , Administração Intranasal , Animais , Asma/induzido quimicamente , Hiper-Reatividade Brônquica/induzido quimicamente , Líquido da Lavagem Broncoalveolar , Modelos Animais de Doenças , Ensaio de Imunoadsorção Enzimática , Feminino , Pulmão/fisiopatologia , Camundongos , Camundongos Endogâmicos BALB C , Ovalbumina/efeitos adversosRESUMO
Polyhexamethylene guanidine phosphate (PHMG-P) has effective antimicrobial activity against various microorganisms and has been widely used as a biocide in commercial products. However, its use as a humidifier disinfectant has provoked fatal idiopathic lung disease in South Korea, especially in pregnant or postpartum women and their young children. PHMG-P-related toxicological studies of reproduction and development in experimental animals have not been identified, and thus, we investigated the potential effects of early-stage oral exposure to PHMG-P by assessing its toxicological properties. PHMG-P was repeatedly administered by oral gavage at dose levels of 0, 13, 40 and 120â¯mg/kg to Sprague-Dawley rats during the pre-mating, mating, gestation and early lactation periods, and then general systemic and reproductive/developmental toxicities were investigated. At 120â¯mg/kg, PHMG-P-related toxicities including subdued behavior, thin appearance, decreased body weight, decreased food consumption and decreased F1 pup body weight were observed. Based on the results of this study, the no-observed-adverse-effect levels (NOAELs) of PHMG-P for both general systemic effects and development are considered to be 40â¯mg/kg/day.
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Anti-Infecciosos/toxicidade , Guanidinas/toxicidade , Troca Materno-Fetal , Administração Oral , Animais , Comportamento Animal/efeitos dos fármacos , Peso Corporal/efeitos dos fármacos , Ingestão de Alimentos/efeitos dos fármacos , Feminino , Fertilidade/efeitos dos fármacos , Masculino , Nível de Efeito Adverso não Observado , Gravidez , Ratos Sprague-Dawley , Reprodução/efeitos dos fármacosRESUMO
Cigarette smoke is known to be associated with the incidence of a variety of pulmonary diseases, and alveolar macrophages are a key player in the defense mechanism against inhalable toxicants. Herein, we have found that a hydrophilic fraction in smoke extracts from 3R4F reference cigarettes (CSE) contains high concentrations of volatile substances compared to cigarette smoke condensate (amphoteric fraction). We also identified the toxic mechanism of CSE using MH-S, a mouse alveolar macrophage cell line. CSE decreased cell viability accompanying increased lactate dehydrogenase release. Additionally, mitochondrial volume and the potential increased along with enhanced expression of mitochondrial fusion proteins and decreased adenosine triphosphate production. Similarly, CSE clearly induced increase of catalase activity and intracellular calcium concentration and decrease of endoplasmic reticulum and lysosome volume at the highest dose. More interestingly, damaged organelles accumulated in the cytosol, and CSE-containing particles specifically penetrated to mitochondria. Meanwhile, any significant change in autophagy related protein expression was not found in CSE-treated cells. Subsequently, we evaluated the effects of CSE on secretion of inflammatory related cytokines and chemokines, considering the relationship between organelle damage and the disturbed immune response. Very importantly, we found that expression of innate and adaptive immunity related mediators is disrupted following CSE exposure. Taken together, we suggest that CSE may cause the accumulation of damaged organelles in the cytoplasm by impairing selective autophagic function. In addition, this accumulation is responsible for the inadequate ability of immune cells to repair the damage of lung tissue following exposure to CSE.
Assuntos
Doenças por Armazenamento dos Lisossomos/induzido quimicamente , Macrófagos Alveolares/efeitos dos fármacos , Nicotiana/efeitos adversos , Fumaça/efeitos adversos , Animais , Apoptose/efeitos dos fármacos , Autofagia/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Inflamação/etiologia , Macrófagos Alveolares/metabolismo , Camundongos , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/patologia , Organelas/efeitos dos fármacos , Organelas/metabolismo , Organelas/patologia , Estresse Oxidativo/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismoRESUMO
Pulmonary fibrosis is a chronic progressive disease with unknown etiology and has poor prognosis. Polyhexamethyleneguanidine phosphate (PHMG-P) causes acute interstitial pneumonia and pulmonary fibrosis in humans when it exposed to the lung. In a previous study, when rats were exposed to PHMG-P through inhalation for 3â¯weeks, lung inflammation and fibrosis was observed even after 3â¯weeks of recovery. In this study, we aimed to determine the time course of PHMG-P-induced lung inflammation and fibrosis. We compared pathological action of PHMG-P with that of bleomycin (BLM) and investigated the mechanism underlying PHMG-P-induced lung inflammation and fibrosis. PHMG-P (0.9â¯mg/kg) or BLM (1.5â¯mg/kg) was intratracheally administered to mice. At weeks 1, 2, 4 and 10 after instillation, the levels of inflammatory and fibrotic markers and the expression of inflammasome proteins were measured. The inflammatory and fibrotic responses were upregulated until 10 and 4â¯weeks in the PHMG-P and BLM groups, respectively. Immune cell infiltration and considerable collagen deposition in the peribronchiolar and interstitial areas of the lungs, fibroblast proliferation, and hyperplasia of type II epithelial cells were observed. NALP3 inflammasome activation was detected in the PHMG-P group until 4â¯weeks, which is suspected to be the main reason for the persistent inflammatory response and exacerbation of fibrotic changes. Most importantly, the pathological changes in the PHMG-P group were similar to those observed in humidifier disinfectant-associated patients. A single exposure of PHMG-P led to persistent pulmonary inflammation and fibrosis for at least 10â¯weeks.
Assuntos
Guanidinas/toxicidade , Pneumonia/induzido quimicamente , Pneumonia/patologia , Fibrose Pulmonar/induzido quimicamente , Fibrose Pulmonar/patologia , Animais , Peso Corporal/efeitos dos fármacos , Peso Corporal/fisiologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Distribuição Aleatória , Fatores de TempoRESUMO
Cadmium (Cd) is a toxic metal present in tobacco smoke, air, food, and water. Inhalation is an important route of Cd exposure, and lungs are one of the main target organs for metal-induced toxicity. Cd inhalation is associated with an increased risk of pulmonary diseases. The present study aimed to assess the effects of repeated exposure to low-dose Cd in a mouse model of polyhexamethylene guanidine (PHMG)-induced lung fibrosis. Mice were grouped into the following groups: vehicle control (VC), PHMG, cadmium chloride (CdCl2), and PHMG + CdCl2. Animals in the PHMG group exhibited increased numbers of total cells and inflammatory cells in the bronchoalveolar lavage fluid (BALF) accompanied by inflammation and fibrosis in lung tissues. These parameters were exacerbated in mice in the PHMG + CdCl2 group. In contrast, mice in the CdCl2 group alone displayed only minimal inflammation in pulmonary tissue. Expression of inflammatory cytokines and fibrogenic mediators was significantly elevated in lungs of mice in the PHMG group compared with that VC. Further, expression of these cytokines and mediators was enhanced in pulmonary tissue in mice administered PHMG + CdCl2. Data demonstrate that repeated exposure to low-dose Cd may enhance the development of PHMG-induced pulmonary fibrosis.
Assuntos
Cloreto de Cádmio/toxicidade , Cádmio/toxicidade , Guanidinas/administração & dosagem , Pulmão/patologia , Fibrose Pulmonar/patologia , Administração por Inalação , Animais , Modelos Animais de Doenças , Masculino , Camundongos Endogâmicos C57BL , Fibrose Pulmonar/induzido quimicamenteRESUMO
Nanoparticles (NPs) have recently emerged as an inhalable pollutant, owing to their applications, aluminum-based NPs (Al-NPs) have been prioritized for toxicity testing. In the current study, we compared the pulmonary biopersistence and subsequent toxicity of four different types of Al-NPs (two rod-type aluminum oxide NPs [AlONPs] with different aspect ratios [short (S)- and long (L)-AlONPs], spherical aluminum cerium oxide NPs [AlCeO3 , AlCeONPs] and spherical γ-aluminum oxide hydroxide nanoparticles [AlOOHNPs]) 13weeks after a single intratracheal instillation, considering the importance of their properties in their toxicity. We found that the pulmonary biopersistence of Al-NPs was strengthened by a high aspect ratio in the rod-type AlONPs and by the presence of hydroxyl groups in the spherical-type Al-NPs. The highest toxicity was observed in the mice treated with AlOOHNPs, which showed low biostability. More importantly, we identified that the commercially available AlCeONPs were Al2 O3 -coated CeO2 NPs, but not AlCeO3 NPs, although they have been sold under the trade name of AlCeONPs. In conclusion, the aspect ratio and biostability may be important factors in the determination of the biopersistence of NPs and the subsequent biological response. In addition, the physicochemical properties of NPs should be examined in detail before their release into the market to prevent unexpected adverse health effects.
Assuntos
Alumínio/toxicidade , Nanopartículas Metálicas/toxicidade , Alumínio/administração & dosagem , Animais , Basófilos/efeitos dos fármacos , Líquido da Lavagem Broncoalveolar/química , Líquido da Lavagem Broncoalveolar/citologia , Ensaio de Imunoadsorção Enzimática , Eosinófilos/efeitos dos fármacos , L-Lactato Desidrogenase/efeitos dos fármacos , L-Lactato Desidrogenase/metabolismo , Contagem de Leucócitos , Pulmão/efeitos dos fármacos , Pulmão/patologia , Contagem de Linfócitos , Linfócitos/efeitos dos fármacos , Macrófagos/efeitos dos fármacos , Masculino , Nanopartículas Metálicas/administração & dosagem , Nanopartículas Metálicas/química , Camundongos , Camundongos Endogâmicos ICR , Neutrófilos/efeitos dos fármacosRESUMO
Nintedanib (NDN), a tyrosine kinase inhibitor, has been shown to have anti-tumor, anti-inflammatory, and anti-fibrotic effects in several reports. We investigated the protective effects of NDN against polyhexamethylene guanidine phosphate (PHMG)-induced lung fibrosis in mice. The following three experimental groups were evaluated: (1) vehicle control; (2) PHMG (1.1 mg/kg); and (3) PHMG & NDN (60 mg/kg). PHMG induced pulmonary inflammation and fibrosis by intratracheal instillation in mice. In contrast, NDN treatment effectively alleviated the PHMG induced lung injury, and attenuated the number of total cells and inflammatory cells in the bronchoalveolar lavage fluid, including the fibrotic histopathological changes, and also reduced the hydroxyproline content. NDN also significantly decreased the expression of inflammatory cytokines and fibrotic factors, and the activation of the NLRP3 inflammasome in lung tissues. These results suggest that NDN may mitigate the inflammatory response and development of pulmonary fibrosis in the lungs of mice treated with PHMG.