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1.
Part Fibre Toxicol ; 19(1): 27, 2022 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-35395797

RESUMO

BACKGROUND: In Japan, six workers handling cross-linked water-soluble acrylic acid polymer (CWAAP) at a chemical plant suffered from lung diseases, including fibrosis, interstitial pneumonia, emphysema, and pneumothorax. We recently demonstrated that inhalation of CWAAP-A, one type of CWAAP, causes pulmonary disorders in rats. It is important to investigate dose-response relationships and recoverability from exposure to CWAAPs for establishing occupational health guidelines, such as setting threshold limit value for CWAAPs in the workplace. METHODS: Male and female F344 rats were exposed to 0.3, 1, 3, or 10 mg/m3 CWAAP-A for 6 h/day, 5 days/week for 13 weeks using a whole-body inhalation exposure system. At 1 h, 4 weeks, and 13 weeks after the last exposure the rats were euthanized and blood, bronchoalveolar lavage fluid, and all tissues including lungs and mediastinal lymph nodes were collected and subjected to biological and histopathological analyses. In a second experiment, male rats were pre-treated with clodronate liposome or polymorphonuclear leukocyte-neutralizing antibody to deplete macrophages or neutrophils, respectively, and exposed to CWAAP-A for 6 h/day for 2 days. RESULTS: CWAAP-A exposure damaged only the alveoli. The lowest observed adverse effect concentration (LOAEC) was 1 mg/m3 and the no observed adverse effect concentration (NOAEC) was 0.3 mg/m3. Rats of both sexes were able to recover from the tissue damage caused by 13 weeks exposure to 1 mg/m3 CWAAP-A. In contrast, tissue damage caused by exposure to 3 and 10 mg/m3 was irreversible due to the development of interstitial lung lesions. There was a gender difference in the recovery from CWAAP-A induced pulmonary disorders, with females recovering less than males. Finally, acute lung effects caused by CWAAP-A were significantly reduced by depletion of alveolar macrophages. CONCLUSIONS: Pulmonary damage caused by inhalation exposure to CWAAP-A was dose-dependent, specific to the lung and lymph nodes, and acute lung damage was ameliorated by depleting macrophages in the lungs. CWAAP-A had both a LOAEC and a NOAEC, and tissue damage caused by exposure to 1 mg/m3 CWAAP-A was reversible: recovery in female rats was less than for males. These findings indicate that concentration limits for CWAAPs in the workplace can be determined.


Assuntos
Exposição por Inalação , Pneumonia , Acrilatos , Animais , Líquido da Lavagem Broncoalveolar , Feminino , Exposição por Inalação/efeitos adversos , Pulmão , Masculino , Pneumonia/patologia , Polímeros/farmacologia , Ratos , Ratos Endogâmicos F344 , Água
2.
Toxins (Basel) ; 14(4)2022 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-35448876

RESUMO

Glucocorticoid-resistant asthma, which predominates with neutrophils instead of eosinophils, is an increasing health concern. One potential source for the induction of neutrophil-predominant asthma is aerosolized lipopolysaccharide (LPS). Cyanobacteria have recently caused significant tidal blooms, and aerosolized cyanobacterial LPS has been detected near the cyanobacterial overgrowth. We hypothesized that cyanobacterial LPS contributes to lung inflammation by increasing factors that promote lung inflammation and neutrophil recruitment. To test this hypothesis, c57Bl/6 mice were exposed intranasally to LPS from the cyanobacterium member, Geitlerinema sp., in vivo to assess neutrophil infiltration and the production of pro-inflammatory cytokines and chemokines from the bronchoalveolar fluid by ELISA. Additionally, we exposed the airway epithelial cell line, A549, to Geitlerinema sp. LPS in vitro to confirm that airway epithelial cells were stimulated by this LPS to increase cytokine production and the expression of the adhesion molecule, ICAM-1. Our data demonstrate that Geitlerinema sp. LPS induces lung neutrophil infiltration, the production of pro-inflammatory cytokines such as Interleukin (IL)-6, Tumor necrosis factor-alpha, and Interferongamma as well as the chemokines IL-8 and RANTES. Additionally, we demonstrate that Geitlerinema sp. LPS directly activates airway epithelial cells to produce pro-inflammatory cytokines and the adhesion molecule, Intercellular Adhesion Molecule-1 (ICAM-1), in vitro using the airway epithelial cell line, A549. Based on our findings that use Geitlerinema sp. LPS as a model system, the data indicate that cyanobacteria LPS may contribute to the development of glucocorticoid-resistant asthma seen near water sources that contain high levels of cyanobacteria.


Assuntos
Asma , Cianobactérias , Pneumonia , Animais , Asma/patologia , Quimiocinas/metabolismo , Cianobactérias/metabolismo , Citocinas/metabolismo , Glucocorticoides/metabolismo , Inflamação/metabolismo , Molécula 1 de Adesão Intercelular/metabolismo , Lipopolissacarídeos/metabolismo , Lipopolissacarídeos/toxicidade , Pulmão/patologia , Camundongos , Infiltração de Neutrófilos , Neutrófilos/metabolismo , Pneumonia/induzido quimicamente , Pneumonia/metabolismo , Pneumonia/patologia
3.
BMC Pulm Med ; 22(1): 160, 2022 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-35473605

RESUMO

BACKGROUND: Smoke exposure culminates as a progressive lung complication involving airway inflammation and remodeling. While primary smoke poses the greatest risk, nearly half of the US population is also at risk due to exposure to secondhand smoke (SHS). METHODS: We used WT, RAGE-/- (KO), and Tet-inducible lung-specific RAGE overexpressing transgenic (TG) mice to study the role of RAGE during short-term responses to SHS. We evaluated SHS effects in mice with and without semi-synthetic glycosaminoglycan ethers (SAGEs), which are anionic, partially lipophilic sulfated polysaccharide derivatives known to inhibit RAGE signaling. TG Mice were weaned and fed doxycycline to induce RAGE at postnatal day (PN) 30. At PN40, mice from each line were exposed to room air (RA) or SHS from three Kentucky 3R4F research cigarettes via a nose-only delivery system (Scireq Scientific, Montreal, Canada) five days a week and i.p. injections of PBS or SAGE (30 mg/kg body weight) occurred three times per week from PN40-70 before mice were sacrificed on PN70. RESULTS: RAGE mRNA and protein expression was elevated following SHS exposure of control and TG mice and not detected in RAGE KO mice. Bronchoalveolar lavage fluid (BALF) analysis revealed RAGE-mediated influence on inflammatory cell diapedesis, total protein, and pro-inflammatory mediators following exposure. Lung histological assessment revealed indistinguishable morphology following exposure, yet parenchymal apoptosis was increased. Inflammatory signaling intermediates such as Ras and NF-κB, as well as downstream responses were influenced by the availability of RAGE, as evidenced by RAGE KO and SAGE treatment. CONCLUSIONS: These data provide fascinating insight suggesting therapeutic potential for the use of RAGE inhibitors in lungs exposed to SHS smoke.


Assuntos
Pneumonia , Poluição por Fumaça de Tabaco , Animais , Éteres , Glicosaminoglicanos , Humanos , Camundongos , Camundongos Transgênicos , Pneumonia/patologia , Receptor para Produtos Finais de Glicação Avançada/genética , Receptor para Produtos Finais de Glicação Avançada/metabolismo , Poluição por Fumaça de Tabaco/efeitos adversos
4.
Malays J Pathol ; 44(1): 83-92, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35484890

RESUMO

INTRODUCTION: Data on pathological changes in COVID-19 are scarce. The aim of this study was to describe the histopathological and virological findings of postmortem biopsies, and the existing clinical correlations, in people who died of COVID-19. MATERIALS AND METHODS: We performed postmortem needle core biopsies of the chest in 11 people who died of COVID-19 pneumonia. Tissue examination was done by light microscopy and real-time polymerase chain reaction (RTPCR). RESULTS: The age of the patients were between 61 to 94 years. Of the 11 postmortem chest biopsies, lung tissue was obtained in 8, myocardium tissue in 7, and liver tissue in 5. Histologically of lung, the main findings pertaining to the lung were diffuse alveolar damage in proliferative phase (n = 4, 50%), diffuse alveolar damage in exudative and proliferative phase (n = 3, 37.5%), diffuse alveolar damage in exudative (n=1; 12.5%) and acute pneumonia (n = 2, 25%). Necrotising pneumonia, acute fibrinous and organising pneumonia, and neutrophils were detected in one sample each (12.5%). Another case presented myocarditis. RT-PCR showed RNA of SARS-CoV-2 in 7 of the 8 lung samples (87.5%), 2 of the 7 myocardial tissue samples (28.6%), and 1 of the 5 liver tissue samples (20%). CONCLUSION: The postmortem examinations show diffuse alveolar damage, as well as acute or necrotising pneumonia. RT-PCR of SARS-CoV-2 was positive in most lung samples.


Assuntos
COVID-19 , Pneumonia Necrosante , Pneumonia , Idoso , Idoso de 80 Anos ou mais , Biópsia por Agulha , Humanos , Fígado/patologia , Pulmão/patologia , Pessoa de Meia-Idade , Pneumonia/patologia , Pneumonia Necrosante/patologia , SARS-CoV-2
5.
J Transl Med ; 20(1): 130, 2022 03 16.
Artigo em Inglês | MEDLINE | ID: mdl-35296330

RESUMO

Asthma is a common respiratory disease, and immune system dysregulation has direct relevance to asthma pathogenesis. Probiotics and prebiotics have immunomodulatory effects and can regulate immune responses and may attenuate allergic reactions. Therefore, in this study, we explored the role of probiotics and prebiotics in regulating acute airway inflammation and the TLR4/NF-kB pathway. Allergic asthma model of BALB/c mice was produced and treated with probiotics (LA-5, GG, and BB-12) and prebiotics (FOS and GOS). Then AHR, BALF cells count, EPO activity, IL-4, 5, 13, 17, 25, 33, as well as IFN-γ, total and OVA-specific IgE, IgG1, Cys-LT, LTB4, LTC4, and TSLP levels were measured. Also, the GTP/GOT assay was performed and gene expression of Akt, NLR3, NF-kB, PI3K, MyD88, TLR4, CCL11, CCL24, MUC5a, Eotaxin, IL-38, and IL-8 were determined. Finally, lung histopathological features were evaluated. Treatment with probiotics could control AHR, eosinophil infiltration to the BALF and reduce the levels of immunoglobulins, IL-17, GTP and also decrease mucus secretion, goblet cell hyperplasia, peribronchial and perivascular inflammation and also, EPO activity. It could reduce gene expression of TLR4 and CCL11. On the other hand, IL-38 gene expression was increased by both probiotic and prebiotic treatment. Treatment with probiotics and prebiotics could control levels of IL-4, 5, 13, 25, 33, leukotrienes, the gene expression of AKT, NLR3, NF-κB, MyD88, MUC5a. The prebiotic treatment could control peribronchial inflammation and PI3K gene expression. Both of the treatments had no significant effect on the GOT, TSLP and IL-8, eotaxin and CCL24 gene expression. Probiotics and prebiotics could induce tolerance in allegro-inflammatory reactions and alter immune responses in allergic conditions. Probiotics could also modulate cellular and humoral immune responses and prevent allergic disorders.


Assuntos
Asma , Pneumonia , Probióticos , Animais , Asma/metabolismo , Inflamação/patologia , Pulmão/patologia , Camundongos , NF-kappa B/metabolismo , Ovalbumina , Pneumonia/patologia , Prebióticos/efeitos adversos , Probióticos/farmacologia , Probióticos/uso terapêutico , Transdução de Sinais , Receptor 4 Toll-Like/metabolismo
6.
Cells ; 11(5)2022 02 24.
Artigo em Inglês | MEDLINE | ID: mdl-35269409

RESUMO

DNA methyltransferase 3b (Dnmt3b) has been suggested to play a role in the host immune response during bacterial infection. Neutrophils and other myeloid cells are crucial for lung defense against Pseudomonas (P.) aeruginosa infection. This study aimed to investigate the role of Dnmt3b in neutrophils and myeloid cells during acute pneumonia caused by P. aeruginosa. Neutrophil-specific (Dnmt3bfl/flMrp8Cre) or myeloid cell-specific (Dnmt3bfl/flLysMCre) Dnmt3b-deficient mice and littermate control mice were infected with P. aeruginosa PAK via the airways. Bacteria burdens, neutrophil recruitment, and activation (CD11b expression, myeloperoxidase, and elastase levels), interleukin (IL)-1ß, IL-6, and tumor necrosis factor (TNF) were measured in bronchoalveolar lavage fluid (BALF) at 6 and 24 h after infection. Our data showed that the bacterial loads and neutrophil recruitment and activation did not differ in BALF obtained from neutrophil-specific Dnmt3b-deficient and control mice, whilst BALF IL-6 and TNF levels were lower in the former group at 24 but not at 6 h after infection. None of the host response parameters measured differed between myeloid cell-specific Dnmt3b-deficient and control mice. In conclusion, dnmt3b deficiency in neutrophils or myeloid cells does not affect acute immune responses in the airways during Pseudomonas pneumonia.


Assuntos
Pneumonia , Infecções por Pseudomonas , Animais , DNA (Citosina-5-)-Metiltransferases , Imunidade , Interleucina-6/metabolismo , Camundongos , Neutrófilos/metabolismo , Pneumonia/patologia , Pseudomonas , Pseudomonas aeruginosa/fisiologia
7.
Sci Rep ; 12(1): 4270, 2022 03 11.
Artigo em Inglês | MEDLINE | ID: mdl-35277562

RESUMO

Inflammatory burden is associated with COVID-19 severity and outcomes. Residual computed tomography (CT) lung abnormalities have been reported after COVID-19. The aim was to evaluate the association between inflammatory burden during COVID-19 and residual lung CT abnormalities collected on follow-up CT scans performed 2-3 and 6-7 months after COVID-19, in severe COVID-19 pneumonia survivors. C-reactive protein (CRP) curves describing inflammatory burden during the clinical course were built, and CRP peaks, velocities of increase, and integrals were calculated. Other putative determinants were age, sex, mechanical ventilation, lowest PaO2/FiO2 ratio, D-dimer peak, and length of hospital stay (LOS). Of the 259 included patients (median age 65 years; 30.5% females), 202 (78%) and 100 (38.6%) had residual, predominantly non-fibrotic, abnormalities at 2-3 and 6-7 months, respectively. In age- and sex-adjusted models, best CRP predictors for residual abnormalities were CRP peak (odds ratio [OR] for one standard deviation [SD] increase = 1.79; 95% confidence interval [CI] = 1.23-2.62) at 2-3 months and CRP integral (OR for one SD increase = 2.24; 95%CI = 1.53-3.28) at 6-7 months. Hence, inflammation is associated with short- and medium-term lung damage in COVID-19. Other severity measures, including mechanical ventilation and LOS, but not D-dimer, were mediators of the relationship between CRP and residual abnormalities.


Assuntos
COVID-19/patologia , Pneumonia/diagnóstico por imagem , Idoso , Proteína C-Reativa/análise , COVID-19/complicações , COVID-19/diagnóstico por imagem , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Gravidade do Paciente , Pneumonia/etiologia , Pneumonia/patologia , Estudos Retrospectivos , Fatores de Risco , Fatores de Tempo , Tomografia Computadorizada por Raios X
8.
Sci Rep ; 12(1): 4080, 2022 03 08.
Artigo em Inglês | MEDLINE | ID: mdl-35260752

RESUMO

During influenza A virus (IAV) infection, it is unclear whether type I interferons (IFNs) have defensive antiviral effects or contribute to immunopathology in smokers. We treated nonsmoking (NS) and cigarette smoke (CS)-exposed mice intranasally with early (prophylactic) or late (therapeutic) IFN-ß. We compared the mortality and innate immune responses of the treated mice following challenge with IAV. In NS mice, both early and late IFN-ß administration decreased the survival rate in mice infected with IAV, with late IFN-ß administration having the greatest effect on survival. In contrast, in CS-exposed mice, early IFN-ß administration significantly increased survival during IAV infection while late IFN-ß administration did not alter mortality. With regards to inflammation, in NS mice, IFN-ß administration, especially late administration, significantly increased IAV-induced inflammation and lung injury. Early IFN-ß administration to CS-exposed mice did not increase IAV-induced inflammation and lung injury as occurred in NS mice. Our results demonstrate, although IFN-ß administration worsens the susceptibility of NS mice to influenza infection with increased immunopathology, early IFN-ß administration to CS-exposed mice, which have suppression of the intrinsic IFN response, improved outcomes during influenza infection.


Assuntos
Fumar Cigarros , Doenças Transmissíveis , Vírus da Influenza A Subtipo H1N1 , Vírus da Influenza A , Influenza Humana , Lesão Pulmonar , Infecções por Orthomyxoviridae , Pneumonia , Animais , Doenças Transmissíveis/patologia , Humanos , Inflamação/patologia , Interferon beta , Pulmão/patologia , Lesão Pulmonar/patologia , Camundongos , Camundongos Endogâmicos C57BL , Pneumonia/patologia , Pneumonia/prevenção & controle , Tabaco
9.
Regul Toxicol Pharmacol ; 130: 105127, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35124137

RESUMO

In vitro studies have shown that cobalt substances predominantly induce pre-inflammatory biomarkers, resulting in a grouping of substances either predicted to cause inflammation following inhalation, or those with a different reactivity profile (poorly-reactive). There is a lack of data on whole-organ lung responses following inhalation of these substances, especially relating to the poorly-reactive group. It is of interest to generate tissue-specific histopathological correlation to better ascertain the predictive nature of the lower tier tests (i.e. tier 1 - bioelution, tiers 2a and b - in vitro markers and ToxTracker testing), in order to understand the type of effects caused by the poorly-reactive group and to gauge long-term effects. Eight cobalt substances were tested in vivo in a customized 4-h toxicity test; with animals sacrificed up to 14-days post-exposure. Histopathological severity scores were assigned based on inflammatory and pre-carcinogenic markers. A clear pattern emerged, with the reactive substances causing a persistent increase in one or more of the selected markers, and absence of these markers with poorly-reactive substances. Longer-term studies should be conducted to investigate the repeated dose effects of the poorly-reactive substances.


Assuntos
Cobalto/toxicidade , Exposição por Inalação/efeitos adversos , Pulmão/efeitos dos fármacos , Pneumonia/patologia , Animais , Biomarcadores Tumorais , Relação Dose-Resposta a Droga , Feminino , Mediadores da Inflamação/metabolismo , Masculino , Tamanho da Partícula , Ratos , Ratos Sprague-Dawley , Testes de Toxicidade
10.
Regul Toxicol Pharmacol ; 130: 105129, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35124138

RESUMO

Lung cancer following inhalation in rodents is a major concern regarding exposure to cobalt substances. However, little information is available on adverse effects and toxicity following long-term inhalation exposure to poorly soluble cobalt substances with low bioavailability. Thus, the present study focused on pulmonary effects of the poorly soluble tricobalt tetraoxide (5, 20, 80 mg/m³) in a 28-day inhalation exposure study. Lung weights increased with increasing exposures. Bronchoalveolar lavage fluid analysis and histopathology revealed lung tissue inflammation at the mid-dose with increasing severity in the high-dose group and post-exposure persistency. Markers for cellular damage and cell proliferation were statistically significantly increased. No increase in 8-OH-dG lesions was observed, indicating an absence of oxidative DNA lesions. The primary effect of inhaled Co3O4 particles is inflammation of the respiratory tract strongly resembling responses of inhaled "inert dust" substances, with a NOAEC of 5 mg/m³ under the conditions of this test.


Assuntos
Cobalto/toxicidade , Pulmão/efeitos dos fármacos , Óxidos/toxicidade , Pneumonia/patologia , Animais , Líquido da Lavagem Broncoalveolar/citologia , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Feminino , Exposição por Inalação , Masculino , Tamanho da Partícula , Distribuição Aleatória , Ratos , Testes de Toxicidade
11.
PLoS One ; 17(2): e0263151, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35157702

RESUMO

The expression of TNF-Receptor Associated Factor 6 (TRAF6) is essential for many physiological processes. Here we studied the phenotype of TRAF6[L74H] knock-in mice which are devoid of TRAF6 E3 ligase activity in every cell of the body, but express normal levels of the TRAF6 protein. Remarkably, TRAF6[L74H] mice have none of the phenotypes seen in TRAF6 KO mice. Instead TRAF6[L74H] mice display an entirely different phenotype, exhibiting autoimmunity, and severe inflammation of the skin and modest inflammation of the liver and lungs. Similar to mice with a Treg-specific knockout of TRAF6, or mice devoid of TRAF6 in all T cells, the CD4+ and CD8+ T cells in the spleen and lymph nodes displayed an activated effector memory phenotype with CD44high/CD62Llow expression on the cell surface. In contrast, T cells from WT mice exhibited the CD44low/CD62Lhigh phenotype characteristic of naïve T cells. The onset of autoimmunity and autoinflammation in TRAF6[L74H] mice (two weeks) was much faster than in mice with a Treg-specific knockout of TRAF6 or lacking TRAF6 expression in all T cells (2-3 months) and we discuss whether this may be caused by secondary inflammation of other tissues. The distinct phenotypes of mice lacking TRAF6 expression in all cells appears to be explained by their inability to signal via TNF Receptor Superfamily members, which does not seem to be impaired significantly in TRAF6[L74H] mice.


Assuntos
Doenças Autoimunes/patologia , Receptores Tipo I de Interleucina-1/metabolismo , Fator 6 Associado a Receptor de TNF/genética , Fator 6 Associado a Receptor de TNF/metabolismo , Receptores Toll-Like/metabolismo , Animais , Doenças Autoimunes/genética , Linfócitos T CD4-Positivos/metabolismo , Linfócitos T CD8-Positivos/metabolismo , Dermatite/genética , Dermatite/patologia , Técnicas de Introdução de Genes , Camundongos , Camundongos Knockout , Fenótipo , Pneumonia/genética , Pneumonia/patologia , Transdução de Sinais
12.
Regul Toxicol Pharmacol ; 130: 105140, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35158000

RESUMO

A mode of action (MOA) for cobalt substances based on the "International Programme on Chemical Safety Conceptual Framework for Evaluating a MOA for Chemical Carcinogenesis" is presented. The data recorded therein were generated in a tiered testing program described in the preceding papers of this special issue, as well as data from the public domain. The following parameters were included in the evaluation: solubility of cobalt substances in artificial lung fluids (bioelution), in vitro biomarkers for cytotoxicity, reactive oxygen species and hypoxia mimicry, inhalation toxicity following acute exposure and repeated dose inhalation effects. Two distinct groups of cobalt substances emerged: substances inducing all effects across the MOA form one group, associated with the adverse outcome of lung cancer in rodents upon chronic exposure. Another group of cobalt substances induces no or very limited effects in the in vitro and acute testing. Higher tier testing with a representative of this group, tricobalt tetraoxide, showed a response resembling rat lung overload following exposure to high concentrations of poorly soluble particles. Based on the fundamental differences in the lower tier toxicological profile, cobalt substances with an unknown hazard profile can be assigned to either group based on lower tier testing alone.


Assuntos
Cobalto/toxicidade , Neoplasias Pulmonares/induzido quimicamente , Neoplasias Pulmonares/patologia , Animais , Cobalto/farmacologia , Relação Dose-Resposta a Droga , Hipóxia/patologia , Exposição por Inalação , Camundongos , Estresse Oxidativo/efeitos dos fármacos , Pneumonia/patologia , Ratos , Espécies Reativas de Oxigênio/metabolismo , Medição de Risco , Solubilidade
13.
Sci Rep ; 12(1): 1764, 2022 02 02.
Artigo em Inglês | MEDLINE | ID: mdl-35110670

RESUMO

Circadian rhythms have a profound effect on lung function and immune-inflammatory response in chronic airway diseases. Thus, understanding the molecular mechanisms of circadian gene expression of core clock-controlled genes (CCGs) may help better understand how it contributes to the physiology and pathology of lung diseases. Ongoing studies have been analyzing gene expression levels of CCGs in mouse lungs using quantitative real-time PCR (qRT-PCR). However, to date, there are no reports on the most stable reference gene in the mouse lung for circadian studies. Herein, we utilized an acute house dust mite (HDM)-sensitization mouse model to evaluate the stability of 10 reference genes commonly used for qRT-PCR normalization using 5 unique algorithms: GeNorm, NormFinder, BestKeeper, RefFinder and Qbase+. Rn18s was determined as the most stable reference gene across all samples evaluated, and Actb, the least stable reference gene. Furthermore, CircWave analysis showed no diurnal variation in the expression pattern for Rn18s but Actb showed strong diurnal changes in the lungs of both PBS (control) and HDM groups. We demonstrate systematically how using Actb as a housekeeping gene offsets the diurnal expression patterns of the CCGs and leads to statistically significant results which may not be the true reflection of the qRT-PCR analysis.


Assuntos
Lesão Pulmonar Aguda/patologia , Ritmo Circadiano , Genes Essenciais , Pneumonia/patologia , Reação em Cadeia da Polimerase em Tempo Real/normas , Software , Lesão Pulmonar Aguda/etiologia , Lesão Pulmonar Aguda/genética , Algoritmos , Animais , Feminino , Perfilação da Expressão Gênica , Regulação da Expressão Gênica , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Pneumonia/etiologia , Pneumonia/genética , Padrões de Referência
15.
Sci Rep ; 12(1): 3121, 2022 02 24.
Artigo em Inglês | MEDLINE | ID: mdl-35210449

RESUMO

18ß-Glycyrrhetinic acid (18ß-GA), the main bioactive component of Glycyrrhizae Radix, is considered a promising anti-inflammatory and antioxidant agent. Here, we evaluated the anti-inflammatory and antioxidant effects of 18ß-GA in an ovalbumin (OVA)-induced asthma mouse model, and examined the role of NF-κB and Nrf2/HO-1 signaling pathways. The histopathological changes of lung tissue in mouse were assessed by histochemical staining and counting of inflammatory cells. The levels of IgE and inflammatory cytokines in the bronchoalveolar lavage fluid of mice were detected by ELISA. In OVA-induced asthmatic mice, 18ß-GA treatment can significantly improve lung function and reduce lung inflammation including infiltration of inflammatory cells. In addition, 18ß-GA reduced the OVA-induced NF-κB phosphorylation in lungs of mice while increasing the expression of Nrf2 and HO-1. These results indicate that 18ß-GA protects OVA-induced allergic inflammation of airway by inhibiting phosphorylation of NF-κB and enhancing the Nrf2/HO-1 pathway, and serves as a potential treatment option for allergic inflammation of airway.


Assuntos
Asma/tratamento farmacológico , Ácido Glicirretínico/análogos & derivados , Inflamação/tratamento farmacológico , Animais , Asma/metabolismo , Líquido da Lavagem Broncoalveolar , China , Citocinas/metabolismo , Modelos Animais de Doenças , Feminino , Ácido Glicirretínico/farmacologia , Heme Oxigenase-1/metabolismo , Imunoglobulina E/metabolismo , Pulmão/patologia , Proteínas de Membrana/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Fator 2 Relacionado a NF-E2/metabolismo , NF-kappa B/metabolismo , Pneumonia/patologia , Transdução de Sinais/efeitos dos fármacos
16.
PLoS One ; 17(2): e0262956, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35104293

RESUMO

INTRODUCTION: Community-acquired pneumonia is associated with higher morbidity, hospitalization, and mortality in adults. Likewise, antimicrobial resistance has increased in recent decades in Ethiopia. Therefore, this study was aimed to determine the bacterial isolates, their antimicrobial susceptibility patterns, and factors associated with community-acquired pneumonia among adult patients in Gondar, Northwest Ethiopia. MATERIALS AND METHODS: This institutional-based cross-sectional study was conducted from April to June 2021. Sociodemographic, clinical, and other relevant data were collected using a pre-tested questionnaire. A total of 312 sputum specimens were collected using sputum cups and inoculated into blood agar, chocolate agar, mannitol salt agar, and MacConkey agar plates, which were then incubated at 37°C for 24 hours. The bacterial isolates were identified based on Gram staining, colony characteristics, and biochemical tests. Antimicrobial susceptibility testing was performed using the Kirby-Bauer disk diffusion method. Inducible clindamycin resistance among the S. aureus isolates was detected by the D-test. Data were entered using EPI data version 4.6 and analyzed using SPSS version 20. P-value ≤ 0.05 at 95% CI was considered statistically significant. RESULTS: Of 312 cases, 39.4% (n = 123; 95% CI: 34.1%-44.9%) were found to have culture-confirmed pneumonia. The most common isolates were K. pneumoniae (31.0%, n = 39), S. pneumoniae (26.2%, n = 33), and S. aureus (20.6%, n = 26). The gram-positive bacteria were susceptible to chloramphenicol (100%) and clindamycin (96.6%). Gram-negative bacteria were susceptible to gentamicin (87.5%), azithromycin (87.1%), ciprofloxacin (86.6%), and ceftriaxone (79.0%) but highly resistant to ampicillin (100%), followed by tetracycline (87.1%), doxycycline (86.4%), co-trimoxazole (80.6%), and amoxicillin-clavulanic acid (79.0%). Overall, 72.2% of the isolates were multi-drug resistant to K. pneumoniae (94.9%, n = 37), E. coli (93.8%, n = 15), and S. pneumoniae (72.7%, n = 24). Only, 7.7% of S. aureus isolates showed inducible clindamycin resistance. Aging (AOR: 3.248, 95% CI: 1.001-10.545, p = 0.050), a history of pneumonia (AOR: 7.004, 95% CI: 3.591-13.658, p = 0.001), alcohol use (AOR: 6.614, 95% CI: 3.399-12.872, p < 0.001), and overcrowded living conditions (AOR: 4.348, 95% CI: 1.964-9.624, p = 0.001) were significantly associated with culture-positive sputum. CONCLUSION AND RECOMMENDATIONS: This study found a high prevalence of bacteria-caused community-acquired pneumonia among adults and low susceptibility to ampicillin, tetracyclines, and amoxicillin-clavulanic acid. Therefore, culture-based bacterial identification and local antibiotic susceptibility testing should be performed regularly. Additionally, new insights into vaccine coverage against highly multi-drug resistant bacteria, particularly K. pneumoniae, are necessary.


Assuntos
Antibacterianos/farmacologia , Infecções Comunitárias Adquiridas/microbiologia , Farmacorresistência Bacteriana Múltipla/efeitos dos fármacos , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Pneumonia/microbiologia , Adolescente , Adulto , Idoso , Cloranfenicol/farmacologia , Ciprofloxacina/farmacologia , Infecções Comunitárias Adquiridas/patologia , Estudos Transversais , Etiópia , Feminino , Bactérias Gram-Negativas/isolamento & purificação , Bactérias Gram-Positivas/isolamento & purificação , Humanos , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Pneumonia/patologia , Escarro/microbiologia , Adulto Jovem
17.
Int J Mol Sci ; 23(3)2022 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-35163010

RESUMO

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.


Assuntos
Niclosamida/administração & dosagem , Pneumonia/tratamento farmacológico , Sistema Respiratório/efeitos dos fármacos , Animais , Asma/tratamento farmacológico , Asma/metabolismo , Asma/patologia , COVID-19/complicações , COVID-19/tratamento farmacológico , Células Cultivadas , Modelos Animais de Doenças , Portadores de Fármacos/química , Composição de Medicamentos , Humanos , Hidrogéis/química , Instilação de Medicamentos , Camundongos , Microesferas , Muco/efeitos dos fármacos , Muco/metabolismo , Nanosferas/administração & dosagem , Nanosferas/química , Niclosamida/química , Niclosamida/farmacocinética , Pneumonia/patologia , Polietilenoglicóis/química , Mucosa Respiratória/efeitos dos fármacos , Mucosa Respiratória/metabolismo , Sistema Respiratório/metabolismo , SARS-CoV-2/efeitos dos fármacos , SARS-CoV-2/fisiologia , Traqueia
18.
Front Immunol ; 13: 790043, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35185885

RESUMO

Diffuse alveolar hemorrhage (DAH), although rare, is a life-threatening complication of systemic lupus erythematosus (SLE). Little is known about the pathophysiology of DAH in humans, although increasingly neutrophils, NETosis and inflammatory monocytes have been shown to play an important role in the pristane-induced model of SLE which develops lung hemorrhage and recapitulates many of the pathologic features of human DAH. Using this experimental model, we asked whether endoplasmic reticulum (ER) stress played a role in driving the pathology of pulmonary hemorrhage and what role infiltrating neutrophils had in this process. Analysis of lung tissue from pristane-treated mice showed genes associated with ER stress and NETosis were increased in a time-dependent manner and reflected the timing of CD11b+Ly6G+ neutrophil accumulation in the lung. Using precision cut lung slices from untreated mice we observed that neutrophils isolated from the peritoneal cavity of pristane-treated mice could directly induce the expression of genes associated with ER stress, namely Chop and Bip. Mice which had myeloid-specific deletion of PAD4 were generated and treated with pristane to assess the involvement of PAD4 and PAD4-dependent NET formation in pristane-induced lung inflammation. Specific deletion of PAD4 in myeloid cells resulted in decreased expression of ER stress genes in the pristane model, with accompanying reduction in IFN-driven genes and pathology. Lastly, coculture experiments of human neutrophils and human lung epithelial cell line (BEAS-2b) showed neutrophils from SLE patients induced significantly more ER stress and interferon-stimulated genes in epithelial cells compared to healthy control neutrophils. These results support a pathogenic role of neutrophils and NETs in lung injury during pristane-induced DAH through the induction of ER stress response and suggest that overactivation of neutrophils in SLE and NETosis may underlie development of DAH.


Assuntos
Células Epiteliais/imunologia , Armadilhas Extracelulares/imunologia , Hemorragia/imunologia , Neutrófilos/imunologia , Pneumonia/imunologia , Alvéolos Pulmonares/imunologia , Animais , Modelos Animais de Doenças , Células Epiteliais/patologia , Feminino , Hemorragia/patologia , Humanos , Lúpus Eritematoso Sistêmico/genética , Camundongos , Camundongos Endogâmicos C57BL , Neutrófilos/patologia , Pneumonia/etiologia , Pneumonia/patologia , Alvéolos Pulmonares/patologia , Terpenos/toxicidade
19.
Nature ; 603(7899): 145-151, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35045565

RESUMO

COVID-19, which is caused by infection with SARS-CoV-2, is characterized by lung pathology and extrapulmonary complications1,2. Type I interferons (IFNs) have an essential role in the pathogenesis of COVID-19 (refs 3-5). Although rapid induction of type I IFNs limits virus propagation, a sustained increase in the levels of type I IFNs in the late phase of the infection is associated with aberrant inflammation and poor clinical outcome5-17. Here we show that the cyclic GMP-AMP synthase (cGAS)-stimulator of interferon genes (STING) pathway, which controls immunity to cytosolic DNA, is a critical driver of aberrant type I IFN responses in COVID-19 (ref. 18). Profiling COVID-19 skin manifestations, we uncover a STING-dependent type I IFN signature that is primarily mediated by macrophages adjacent to areas of endothelial cell damage. Moreover, cGAS-STING activity was detected in lung samples from patients with COVID-19 with prominent tissue destruction, and was associated with type I IFN responses. A lung-on-chip model revealed that, in addition to macrophages, infection with SARS-CoV-2 activates cGAS-STING signalling in endothelial cells through mitochondrial DNA release, which leads to cell death and type I IFN production. In mice, pharmacological inhibition of STING reduces severe lung inflammation induced by SARS-CoV-2 and improves disease outcome. Collectively, our study establishes a mechanistic basis of pathological type I IFN responses in COVID-19 and reveals a principle for the development of host-directed therapeutics.


Assuntos
COVID-19/imunologia , COVID-19/patologia , Interferon Tipo I/imunologia , Proteínas de Membrana/metabolismo , Nucleotidiltransferases/metabolismo , SARS-CoV-2/imunologia , Animais , COVID-19/metabolismo , COVID-19/virologia , Células Cultivadas , DNA Mitocondrial/metabolismo , Modelos Animais de Doenças , Progressão da Doença , Células Endoteliais/patologia , Feminino , Regulação da Expressão Gênica/imunologia , Humanos , Imunidade Inata , Pulmão/imunologia , Pulmão/metabolismo , Pulmão/patologia , Pulmão/virologia , Macrófagos/imunologia , Proteínas de Membrana/antagonistas & inibidores , Camundongos , Camundongos Endogâmicos C57BL , Pneumonia/imunologia , Pneumonia/metabolismo , Pneumonia/patologia , Pneumonia/virologia , SARS-CoV-2/patogenicidade , Transdução de Sinais , Pele/imunologia , Pele/metabolismo , Pele/patologia
20.
J Ethnopharmacol ; 287: 114965, 2022 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-34990767

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Coronavirus and influenza virus infection seriously threaten human health. Cangma Huadu Granules (CMHD) is an in-hospital preparation composed of eight traditional Chinese medicines (TCM), which has been clinically used against COVID-19 in China and may be a promising candidate for the treatment of influenza. However, the role of its treatment urgently needs to be studied. AIM OF THE STUDY: To evaluate the therapeutic effects of CMHD on pneumonia induced by coronavirus (HCoV-229E) and influenza A virus (H1N1/FM1) in mice and explore its mechanism of anti-infection. MATERIALS AND METHODS: Mice were infected with HCoV-229E or H1N1/FM1 virus through the nasal cavity. CMHD (12.1, 6.05 and 3.03 g/kg/d) or the positive control drugs were administered intragastrically. The lung index and histopathological changes were used to evaluate the therapeutic effect of CMHD. The expression of TNF-α, IL-1ß, IL-6 and IL-4 in Serum and the proportion of CD4+ and CD8+ T lymphocytes in peripheral blood were detected to evaluate the anti-inflammatory and immune regulation effects of CMHD, respectively. Furthermore, the levels of p-NF-κBp65/ NF-κB p65, which was the key targets of the NF-κB pathway was analyzed. RESULTS: In HCoV-229E-induced pneumonia, the lung index was markedly reduced, and lung pathology was improved in mice that treated with CMHD (12.1, 6.05 g/kg/d). Meanwhile, the expression of TNF-α, IL-6 were obviously inhibited, but the expression of IL-4 was significantly increased in CMHD groups. Compared with the model group, CMHD could also markedly upregulate the level of CD4+ and CD8+. Furthermore, CMHD has a markedly effect on inhibit the expression of p-NF-κB p65/NF-κB p65 in the lung. In H1N1-induced pneumonia, the lung index of mice in the CMHD (12.1 g/kg/d) treatment group was lower than that in the model group, and less inflammatory infiltration could be seen in the lung pathological. Moreover, CMHD could also obviously decrease the expression of TNF-α, IL-1ß, IL-6, but significantly increase the expression of IL-4. Except for that, CMHD could also markedly downregulate the level of CD4+ and upregulate the level of CD8+ compared with the model group. In addition, CMHD has a markedly effect on inhibit the expression of p-NF-κB p65/NF-κB p65 in the lung. CONCLUSION: CMHD can significantly combats viral infections caused by HCoV-229E and H1N1, and the mechanism may be related to its multiple functions of anti-inflammatory, immunity regulating and inhibiting NF-κB signal transduction pathway.


Assuntos
Anti-Inflamatórios/farmacologia , Infecções por Coronavirus/tratamento farmacológico , Medicamentos de Ervas Chinesas/farmacologia , Vírus da Influenza A Subtipo H1N1/efeitos dos fármacos , Medicina Tradicional Chinesa/métodos , Infecções por Orthomyxoviridae/tratamento farmacológico , Animais , Anti-Inflamatórios/uso terapêutico , Coronavirus Humano 229E/efeitos dos fármacos , Citocinas/metabolismo , Modelos Animais de Doenças , Medicamentos de Ervas Chinesas/uso terapêutico , Feminino , Imunidade/efeitos dos fármacos , Masculino , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos ICR , Pneumonia/tratamento farmacológico , Pneumonia/patologia , Linfócitos T/metabolismo , Fator de Transcrição RelA/metabolismo
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