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AIMS: Cigarette smoke often induces pulmonary and systemic inflammation. In animal models, mesenchymal stem cells (MSC) tend to ameliorate these effects. We aimed to explore the local and systemic expression of cytokines in guinea pigs chronically exposed to cigarette smoke, and their modifications by MSC. MAIN METHODS: Concentrations of IL-1ß, IL-6, IL-8, IL-12, TNF-α, INF-É£, TSG-6, MMP-9, TIMP-1, and/or TIMP-2 in serum and bronchoalveolar lavage (BALF) from animals exposed to tobacco smoke (20 cigarettes/day, 5 days/week for 10 weeks) were determined, and mRNA expression of some of them was measured in lung tissue. Intratracheal instillation of allogeneic bone marrow MSC (5x106 cells in 1 ml) was done at week 2. KEY FINDINGS: After cigarette smoke, IL-6 and IFN-γ increased in serum and BALF, while IL-1ß and IL-12 decreased in serum, and TSG-6 and TIMP-2 increased in BALF. IL-1ß had a paradoxical increase in BALF. MSC had an almost null effect in unexposed animals. The intratracheal administration of MSC in guinea pigs exposed to cigarette smoke was associated with a statistically significant decrease of IL-12 and TSG-6 in serum, as well as a decrease of IL-1ß and IFN-γ and an increase in TIMP-1 in BALF. Concerning mRNA expression in lung tissue, cigarette smoke did not modify the relative amount of the studied transcripts, but even so, MSC decreased the IL-12 mRNA and increased the TIMP-1 mRNA. SIGNIFICANCE: A single intratracheal instillation of MSC reduces the pulmonary and systemic proinflammatory pattern induced by chronic exposure to cigarette smoke in guinea pigs. TRIAL REGISTRATION: Not applicable.
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Fumar Cigarros , Células-Tronco Mesenquimais , Cobaias , Animais , Citocinas/metabolismo , Inibidor Tecidual de Metaloproteinase-1/metabolismo , Inibidor Tecidual de Metaloproteinase-2 , Interleucina-6/farmacologia , Fumar Cigarros/efeitos adversos , Pulmão/metabolismo , Interleucina-12/farmacologia , RNA Mensageiro , Células-Tronco Mesenquimais/metabolismo , Líquido da Lavagem BroncoalveolarRESUMO
Communication between neighboring or distant cells is made through a complex network that includes extracellular vesicles (EVs). Exosomes, which are a subgroup of EVs, are released from most cell types and have been found in biological fluids such as urine, plasma, and airway secretions like bronchoalveolar lavage (BAL), nasal lavage, saliva, and sputum. Mainly, the cargo exosomes are enriched with mRNAs and microRNAs (miRNAs), which can be transferred to a recipient cell consequently modifying and redirecting its biological function. The effects of miRNAs derive from their role as gene expression regulators by repressing or degrading their target mRNAs. Nowadays, various types of research are focused on evaluating the potential of exosomal miRNAs as biomarkers for the prognosis and diagnosis of different pathologies. Nevertheless, there are few reports on their role in the pathophysiology of idiopathic pulmonary fibrosis (IPF), a chronic lung disease characterized by progressive lung scarring with no cure. In this review, we focus on the role and effect of exosomal miRNAs as intercellular communicators in the onset and progression of IPF, as well as discussing their potential utility as therapeutic agents for the treatment of this disease.
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Exossomos , Vesículas Extracelulares , Fibrose Pulmonar Idiopática , MicroRNAs , Biomarcadores/metabolismo , Exossomos/genética , Exossomos/metabolismo , Vesículas Extracelulares/metabolismo , Humanos , Fibrose Pulmonar Idiopática/genética , Fibrose Pulmonar Idiopática/metabolismo , MicroRNAs/metabolismo , RNA Mensageiro/genéticaRESUMO
Wood smoke (WS) contains many harmful compounds, including polycyclic aromatic hydrocarbons (PAHs). WS induces inflammation in the airways and lungs and can lead to the development of various acute and chronic respiratory diseases. Pulmonary fibroblasts are the main cells involved in the remodeling of the extracellular matrix (ECM) during the WS-induced inflammatory response. Although fibroblasts remain in a low proliferation state under physiological conditions, they actively participate in ECM remodeling during the inflammatory response in pathophysiological states. Consequently, we used normal human lung fibroblasts (NHLFs) to assess the potential effects of the PAHs-containing wood smoke extract (WSE) on the growth rate, total collagen synthesis, and the expression levels of collagen I and III, matrix metalloproteinase (MMP)-1, MMP-2, MMP-9, tissue inhibitor of metalloproteinase (TIMP)-1, TIMP-2, and the transforming growth factor (TGF)-ß1. We also assessed MMPs activity. The results showed that WSE induced a trimodal behavior in the growth rate curves in NHLFs; the growth rate increased with 0.5-1 % WSE and decreased with 2.5% WSE, without causing cell damage; 5-20% WSE inhibited the growth and induced cell damage. After 3 hours of exposure, 2.5% WSE induced an increase in total collagen synthesis and upregulation of TGF-ß1, collagen I and III, MMP-1, TIMP-1, and TIMP-2 expression. However, MMP-2 expression was downregulated and MMP-9 was not expressed. The gelatinase activity of MMP-2 was also increased. These results suggest that WSE affects the ECM remodeling in NHLFs and indicate the potential involvement of PAHs in this process.
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Matriz Extracelular/efeitos dos fármacos , Fibroblastos/efeitos dos fármacos , Inflamação/induzido quimicamente , Inflamação/fisiopatologia , Pneumopatias/induzido quimicamente , Extratos Vegetais/efeitos adversos , Fumaça/efeitos adversos , Proliferação de Células/efeitos dos fármacos , Humanos , Magnoliopsida/química , Madeira/químicaRESUMO
Idiopathic pulmonary fibrosis (IPF) is a devastating disease characterized by increased activation of fibroblasts/myofibroblasts. Previous reports have shown that IPF fibroblasts are resistant to apoptosis, but the mechanisms remain unclear. Since inhibition of the mitochondrial permeability transition pore (mPTP) has been implicated in the resistance to apoptosis, in this study, we analyzed the role of mitochondrial function and the mPTP on the apoptosis resistance of IPF fibroblasts under basal conditions and after mitomycin C-induced apoptosis. We measured the release of cytochrome c, mPTP opening, mitochondrial calcium release, oxygen consumption, mitochondrial membrane potential, ADP/ATP ratio, ATP concentration, and mitochondrial morphology. We found that IPF fibroblasts were resistant to mitomycin C-induced apoptosis and that calcium, a well-established activator of mPTP, is decreased as well as the release of pro-apoptotic proteins such as cytochrome c. Likewise, IPF fibroblasts showed decreased mitochondrial function, while mPTP was less sensitive to ionomycin-induced opening. Although IPF fibroblasts did not present changes in the mitochondrial membrane potential, we found a fragmented mitochondrial network with scarce, thinned, and disordered mitochondria with reduced ATP levels. Our findings demonstrate that IPF fibroblasts are resistant to mitomycin C-induced apoptosis and that altered mPTP opening contributes to this resistance. In addition, IPF fibroblasts show mitochondrial dysfunction evidenced by a decrease in respiratory parameters.
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Apoptose , Fibroblastos/metabolismo , Fibrose Pulmonar Idiopática/metabolismo , Mitocôndrias/metabolismo , Poro de Transição de Permeabilidade Mitocondrial/metabolismo , Trifosfato de Adenosina/metabolismo , Cálcio/metabolismo , Citocromos c/metabolismo , Fibroblastos/patologia , Humanos , Fibrose Pulmonar Idiopática/etiologia , Fibrose Pulmonar Idiopática/patologia , Ionomicina , Mitocôndrias/patologia , Mitomicina , Oxigênio/metabolismo , Cultura Primária de CélulasRESUMO
The main causes of COPD are smoking (COPD-TS) and exposure to biomass smoke (COPD-BS), considered as different phenotypes. The association of COPD-TS with lung cancer (LC) is well established, but not in COPD-BS. Thus, we studied the serum concentration of cytokines that participate in inflammation, angiogenesis, and tumor progression, used frequently as LC biomarkers, in women with COPD-BS compared with COPD-TS (n = 70). Clinical and physiological characteristics and the serum concentration (multiplex immunoassay) of 16 cytokines were evaluated. The analysis revealed that women with COPD-BS were shorter and older, and had lower concentrations of 12 serum cytokines: 6 proinflammatory and angiogenic IL-6Rα, PECAM-1, leptin, osteopontin, prolactin, and follistatin; and 6 that participate in angiogenesis and in tumor progression FGF-2, HGF, sVEGFR-2, sHER2/neu, sTIE-2, G-CSF, and SCF. Notably, there was a significant increase in sEGFR in women with COPD-BS compared to women with COPD-TS. PDGF-AA/BB and sTIE-2 did not change. These findings suggest that women with COPD-BS have markedly decreased proinflammatory, angiogenic, and tumor progression potential, compared to women with COPD-TS, with sEGFR as the predominant mediator, which might reflect a differential pattern of inflammation in women exposed to BS, favoring the development of chronic bronchitis.
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Neoplasias , Doença Pulmonar Obstrutiva Crônica , Biomarcadores , Biomassa , Receptores ErbB , Feminino , Humanos , Fumaça/efeitos adversos , FumarRESUMO
BACKGROUND: Chronic obstructive pulmonary disease (COPD) is characterized by persistent respiratory symptoms and airflow limitation that is due to airway and/or alveolar abnormalities. The main causes of COPD are Gene-environment interactions associated with tobacco smoking (COPD-TS) and biomass smoke (COPD-BS). It is well know that microRNAs (miRNAs) participate in the control of post-transcriptional regulation and are involved in COPD-TS; nevertheless, those miRNAS are participating in the COPD-BS are unidentified. Thus, we studied which miRNAs are involved in COPD-BS (GOLD stages I-II). METHODS: In the screening phase, the profile of the miRNAs was analyzed in serum samples (n = 3) by means of a PCR array. Subsequently, the miRNAs were validated with RT-qPCR (n = 25) in the corresponding study groups. Additionally, the serum concentration of Notch1 was measured comparing COPD-BS vs COPD-TS. RESULTS: miR-34a was down-regulated in COPD- BS vs COPD-TS. In the other study groups, three miRNAs were differentially expressed: miR-374a was down-regulated in COPD-BS vs C, miR-191-5p was up-regulated in COPD-BS vs H-BS, and miR-21-5p was down-regulated in COPD-TS compared to the C group. Moreover, the serum concentration of Notch1, one of the targets of miR-34a, was increased in COPD-BS compared to women with COPD-TS. CONCLUSIONS: This is the first study in patients with COPD due to biomass that demonstrates miRNA expression differences between patients. The observations support the concept that COPD by biomass has a different phenotype than COPD due to tobacco smoking, which could have important implications for the treatment of these diseases.
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Biomassa , Exposição Ambiental , MicroRNAs/sangue , Doença Pulmonar Obstrutiva Crônica/sangue , Fumaça , Idoso , Exposição Ambiental/efeitos adversos , Feminino , Humanos , Pessoa de Meia-Idade , Doença Pulmonar Obstrutiva Crônica/etiologia , Índice de Gravidade de Doença , Fumaça/efeitos adversosRESUMO
INTRODUCTION: With recent clinical placement demands exceeding supply, the University Health Network (UHN) Respiratory Therapy (RT) department implemented a 2:1 student-to-preceptor model where a focus on peer learning (PL) becomes a key component of program success. PL can be defined as students learning from and with each other in both formal and informal ways. The shift towards facilitative student-directed models in other health care professions can be seen globally with the literature suggesting that 2:1 models not only support increases in student capacity but also improve the student learning experience through PL strategies. The aim of this study was to explore the perceptions of RT preceptors and students regarding the 2:1 model as an educational strategy in the context of their clinical experience. The study further explored experiences of PL to understand how learning is enabled in RT practice-based education, particularly within 2:1 models. METHODS: A qualitative descriptive study using single-episode semi-structured interviews with RT preceptors (n = 10) and students (n = 10) was conducted during the 2015-2016 RT student clinical year. Twelve open-ended interview questions were designed to draw out study participants' PL experiences and exploration of issues using a 2:1 model in the context of their clinical experience. Data were recorded, transcribed verbatim, and analyzed using thematic analysis. RESULTS: The content analysis resulted in two broad themes with respect to the RT 2:1 educational model: "enablers" and "barriers" to a PL approach. The 2:1 model was preferred by students and preceptors early on in the clinical training due to the benefits of PL, whereas opportunities to showcase independent practice was preferred towards the end of their clinical year. Furthermore, careful planning, resources, and supports need to be implemented to augment benefits and diminish potential disadvantages of using a 2:1 model structure. CONCLUSION: Participants felt that a 2:1 model strongly contributes to a supportive learning environment and can have a positive influence on the RT student clinical experience at UHN. Along with the improved critical thinking and student engagement opportunities that a 2:1 model offers, increased placement numbers are also supported.
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INTRODUCTION: Chronic obstructive pulmonary disease (COPD) is a complex and multifactorial disease involving systemic inflammation. Although certain genetic components have been implicated in the development and progression of this disease, few studies have examined the participation of polymorphisms in proinflammatory genes and the extent to which polymorphisms are related to plasma levels of cytokines involved in the inflammatory process. METHODS: Of the 1125 smokers participating in the study, 438 had COPD, and 687 did not. We determined the genotype of 5 SNPs distributed in the genes: IL6, CXL8, CSF2, CCL1 and IL1B. The plasma protein expression of these genes was also evaluated and categorized according to genotype and the severity of COPD (GOLD grade). RESULTS: An analysis using the codominant model showed an association between rs1818879 in IL6 and susceptibility to COPD (GA ORâ¯=â¯1.1, AA ORâ¯=â¯1.77; pâ¯<â¯0.01), as well as an association between rs25882 in CSF2 and a greater severity of the disease (TC ORâ¯=â¯1.84, CC ORâ¯=â¯3.62; pâ¯<â¯0.01). No association was found between the presence of certain alleles in the SNPs and the plasma levels of the corresponding proteins. CONCLUSIONS: There are genetic polymorphisms related to susceptibility to COPD (rs1818879/A in IL6), as well as to the risk of greater severity of the disease (rs25882/T in CSF2). The presence of the alleles of interest did not significantly affect plasma levels of the codified proteins.
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Citocinas/genética , Inflamação/genética , Polimorfismo de Nucleotídeo Único/genética , Doença Pulmonar Obstrutiva Crônica/genética , Idoso , Alelos , Proteínas Sanguíneas/genética , Estudos de Casos e Controles , Feminino , Predisposição Genética para Doença/genética , Genótipo , Humanos , Interleucina-1beta/genética , Interleucina-6/genética , Masculino , Pessoa de Meia-IdadeRESUMO
BACKGROUND: The main causes of COPD are tobacco smoking (COPD-TS) and biomass smoke exposure (COPD-BS). COPD-TS is known to induce changes in adipokines, incretins, and peptide hormones, frequent biomarkers of inflammation; however, it is unknown if similar changes occur in COPD-BS. METHODS: Clinical and physiological characteristics, and serum concentration of C-peptide, ghrelin, GIP, GLP-1, glucagon, insulin, leptin, PAI-1, resistin, and visfatin were measured in women with COPD-BS, COPD-TS, and healthy controls. Data were compared with one-way ANOVA and Tukey's post hoc test; nonparametric were expressed as median (interquartile ranges), with Kruskal-Wallis and Dunn's post-hoc test. Multivariate analysis, age, BMI, MS, and FEV1% pred with levels of inflammatory mediators in COPD women. RESULTS: FEV1% pred, FVC% pred, and FEV1/FVC ratio were decremented in COPD. In COPD-TS increased C-peptide, ghrelin, GIP, GLP-1, and leptin, and reduced glucagon, PAI-1, resistin, and visfatin. In COPD-BS enlarged ghrelin, insulin, leptin, and PAI-1 comparatively with COPD-TS and control, while C-peptide and GLP-1 relatively with controls; conversely, glucagon, and resistin were reduced. Multivariate analysis showed association of ghrelin, insulin, PAI-1, and visfatin with BS exposure. CONCLUSIONS: women with COPD-BS have a distinct profile of adipokines, incretins, and peptide hormones, and specifically with ghrelin, insulin, PAI-1, and visfatin related to BS exposure.
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Adipocinas/sangue , Fumar Cigarros/sangue , Incretinas/sangue , Hormônios Peptídicos/sangue , Doença Pulmonar Obstrutiva Crônica/sangue , Fumantes , Idoso , Idoso de 80 Anos ou mais , Biomarcadores/sangue , Fumar Cigarros/epidemiologia , Feminino , Humanos , Pessoa de Meia-Idade , Doença Pulmonar Obstrutiva Crônica/diagnóstico , Doença Pulmonar Obstrutiva Crônica/epidemiologiaRESUMO
Obesity and emphysema are associated with low-grade systemic inflammation and oxidant stress. Assuming that the oxidant stress induced by emphysema would be decreased by obesity, we analyzed the oxidant/antioxidant state in a rat model combining both diseases simultaneously. Obesity was induced using sucrose, while emphysema by exposure to tobacco smoke. End-points evaluated were: body weight, abdominal fat, plasma dyslipidemia and malondialdehyde (MDA), insulin and glucose AUC, activities of Mn-superoxide dismutase (Mn-SOD), glutathione reductase (GR), glutathione transferase (GST) and glutathione peroxidase (GPx); lung MnSOD and 3-nitrotyrosine (3-NT) immunostaining, and expression of αV and ß6 integrin subunits. In rats with obesity, the body weight, abdominal fat, plasma triglyceride levels, glucose AUC, insulin levels, GST activity, and αV and ß6 integrin expressions were amplified. The rats with emphysema had lower values of body weight, abdominal fat, plasma insulin, triglycerides and glucose AUC but higher values of plasma MDA, GPx activity, and the lung expression of the αV and ß6 integrins. The combination of obesity and emphysema compared to either condition alone led to diminished body weight, abdominal fat, plasma insulin MDA levels, GPx and GST activities, and αV and ß6 integrin expressions; these parameters were all previously increased by obesity. Immunostaining for MnSOD augmented in all experimental groups, but the staining for 3-NT only increased in rats treated with tobacco alone or combined with sucrose. Results showed that obesity reduces oxidant stress and integrin expression, increasing antioxidant enzyme activities; these changes seem to partly contribute to a protective mechanism of obesity against emphysema development.
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Enfisema/metabolismo , Pulmão/efeitos dos fármacos , Nicotiana , Obesidade/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Fumaça/efeitos adversos , Animais , Antioxidantes/metabolismo , Glicemia/análise , Enfisema/induzido quimicamente , Teste de Tolerância a Glucose , Peróxidos Lipídicos/metabolismo , Pulmão/metabolismo , Pulmão/patologia , Masculino , Obesidade/complicações , Ratos Wistar , Poluição por Fumaça de Tabaco/efeitos adversosRESUMO
INTRODUCTION: Surfactant protein D (SP-D) plays an important role in the innate responses against pathogens and its production is altered in lung disorders. METHODS: We studied the circulating levels of SP-D in 37 patients with acute respiratory distress syndrome due to the A/H1N1 virus infection and in 40 healthy controls. Cox logistic regression models were constructed to explore the association of SP-D levels and risk of death. RESULTS: Mortality rate after a 28-day was 32.42 %. Significant higher levels of SP-D were detected in A/H1N1 patients with fatal outcome (p < 0.05). After adjusting for confounding variables, levels of SP-D ≥250 ng/mL were associated with increased the risk of death (HR = 8.27, 95 % CI 1.1-64.1, p = 0.043). CONCLUSIONS: Our results revealed that higher circulating levels of SP-D are associated with higher mortality risk in critically ill A/H1N1 patients. SP-D might be a predictive factor of poor outcomes in viral pneumonia.
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Vírus da Influenza A Subtipo H1N1/patogenicidade , Influenza Humana/diagnóstico , Pneumonia Viral/diagnóstico , Proteína D Associada a Surfactante Pulmonar/sangue , Síndrome do Desconforto Respiratório/diagnóstico , Adulto , Biomarcadores/sangue , Estudos de Casos e Controles , Distribuição de Qui-Quadrado , Estado Terminal , Feminino , Mortalidade Hospitalar , Humanos , Influenza Humana/sangue , Influenza Humana/mortalidade , Influenza Humana/terapia , Influenza Humana/virologia , Estimativa de Kaplan-Meier , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Pneumonia Viral/sangue , Pneumonia Viral/mortalidade , Pneumonia Viral/terapia , Pneumonia Viral/virologia , Prognóstico , Modelos de Riscos Proporcionais , Síndrome do Desconforto Respiratório/sangue , Síndrome do Desconforto Respiratório/mortalidade , Síndrome do Desconforto Respiratório/terapia , Síndrome do Desconforto Respiratório/virologia , Fatores de Risco , Fatores de Tempo , Regulação para CimaRESUMO
Domestic exposure to biomass smoke represents the second cause of chronic obstructive lung disease. Previous studies have shown that exposure of guinea pigs to wood smoke is capable of generating oxidative stress in lung tissue, and this may involve a failure at a mitochondrial level, given its close relation with the production of reactive oxygen species (ROS). The purpose of this study was to evaluate, in guinea pigs exposed to wood smoke, the lung mitochondrial functionality through O2 consumption measurement and the determination of the mitochondrial complexes enzymatic activity. We found that normal and maximum respiration decreased at 15 and 30 min of wood smoke exposure, recovering its normal values at 180 min. The same behavior was observed for the respiratory control rate (RCR) and the ADP/O value. Complex I activity decreased significantly after 30 min of exposure and it returned to baseline after 180 min. The greatest alteration was observed by the decrease of 85% on complex IV activity at 30 min of exposure, which returned to control values after 180 min of exposure. It is concluded that even when wood smoke exposure induces severe mitochondrial respiration alterations at the first 30 min, it seems that there is one or many ways by which mitochondria can reinstate its normal function after 180 min of exposure.
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Complexo IV da Cadeia de Transporte de Elétrons/metabolismo , Complexo I de Transporte de Elétrons/metabolismo , Pulmão/metabolismo , Mitocôndrias/metabolismo , Fumaça/efeitos adversos , Madeira , Animais , Respiração Celular , Feminino , Cobaias , Espécies Reativas de Oxigênio/metabolismoRESUMO
BACKGROUND: Matrix metalloproteinases (MMPs) and C-reactive protein (CRP) are involved in chronic obstructive pulmonary disease (COPD) pathogenesis. The aim of the present work was to determine plasma concentrations of MMPs and CRP in COPD associated to biomass combustion exposure (BE) and tobacco smoking (TS). METHODS: Pulmonary function tests, plasma levels of MMP-1, MMP-7, MMP-9, MMP-9/TIMP-1 and CRP were measured in COPD associated to BE (n = 40) and TS (n =40) patients, and healthy non-smoking (NS) healthy women (controls, n = 40). RESULTS: Plasma levels of MMP-1, MMP-7, MMP-9, and MMP-9/TIMP-1 and CRP were higher in BE and TS than in the NS healthy women (p <0.01). An inverse correlation between MMP-1, MMP-7, MMP-9, MMP-9/TIMP-1 and CRP plasma concentrations and FEV1 was observed. CONCLUSIONS: Increase of MMPs and CRP plasma concentrations in BE suggests a systemic inflammatory phenomenon similar to that observed in COPD associated to tobacco smoking, which may also play a role in COPD pathogenesis.
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Proteína C-Reativa/metabolismo , Volume Expiratório Forçado/fisiologia , Metaloproteinase 1 da Matriz/sangue , Metaloproteinase 7 da Matriz/sangue , Metaloproteinase 9 da Matriz/sangue , Doença Pulmonar Obstrutiva Crônica/sangue , Fumar/sangue , Idoso , Idoso de 80 Anos ou mais , Biomarcadores/sangue , Biomassa , Feminino , Óleos Combustíveis/efeitos adversos , Humanos , Pessoa de Meia-Idade , Doença Pulmonar Obstrutiva Crônica/diagnóstico , Doença Pulmonar Obstrutiva Crônica/epidemiologia , Fumaça/efeitos adversos , Fumar/efeitos adversos , Fumar/epidemiologiaRESUMO
Idiopathic pulmonary fibrosis (IPF) is an ageing-related lung disorder characterised by expansion of the myofibroblast population and aberrant lung remodelling. Dehydroepiandrosterone (DHEA), a steroid pro-hormone, decreases with age but an exaggerated decline has been associated with chronic degenerative diseases. We quantified the plasma levels of DHEA and its sulfated form (DHEA-S) in 137 IPF patients and 58 controls and examined the effects of DHEA on human lung fibroblasts. Plasma DHEA/DHEA-S was significantly decreased in male IPF patients (median (range) DHEA: 4.4 (0.2-29.2) versus 6.7 (2.1-15.2) ng · mL(-1), p<0.01; DHEA-S: 47 (15.0-211) versus 85.2 (37.6-247.0) µg · dL(-1), p<0.001), while in females only DHEA-S was significantly decreased (32.6 (15.0-303.0) versus 68.3 (16.4-171) µg · dL(-1), p<0.001). DHEA caused a decrease in fibroblast proliferation and an approximately two-fold increase in fibroblast apoptosis, probably through the intrinsic pathway with activation of caspase-9. This effect was accompanied by upregulation of several pro-apoptotic proteins (Bax and cyclin-dependent kinase-inhibitor CDNK1A) and downregulation of anti-apoptotic proteins, such as cellular inhibitor of apoptosis (c-IAP)1 and c-IAP2. DHEA also caused a significant decrease of transforming growth factor-ß1-induced collagen production and fibroblast to myofibroblast differentiation, and inhibited platelet-derived growth factor-induced fibroblast migration. These findings demonstrate a disproportionate decrease of DHEA/DHEA-S in IPF patients and indicate that this molecule has multiple antifibrotic properties.
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Desidroepiandrosterona/sangue , Desidroepiandrosterona/farmacologia , Fibroblastos/efeitos dos fármacos , Fibrose Pulmonar Idiopática/tratamento farmacológico , Idoso , Apoptose , Lavagem Broncoalveolar , Estudos de Casos e Controles , Caspase 9/metabolismo , Diferenciação Celular/efeitos dos fármacos , Linhagem Celular , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Colágeno/metabolismo , Sulfato de Desidroepiandrosterona/farmacologia , Feminino , Fibroblastos/metabolismo , Perfilação da Expressão Gênica , Humanos , Masculino , Pessoa de Meia-Idade , Fator de Crescimento Derivado de Plaquetas/metabolismo , Fator de Crescimento Transformador beta1/metabolismoRESUMO
Idiopathic pulmonary fibrosis (IPF) is a progressive and irreversible lung disease of unknown etiology. Myofibroblasts are organized in peculiar subepithelial fibroblasts foci (FF), where they abnormally persist and exclude lymphocytes by unclear mechanisms. FF are the source of an excessive extracellular matrix, which results in progressive stiffening and destruction of the lung architecture. We hypothesized that the absence of T cells inside the FF could be related, at least partially, to an inefficient function of lymphocytes induced by IPF fibroblasts. Here, we evaluated the effect of a supernatant from IPF fibroblasts on T-cell apoptosis and migration capacity. Data showed that IPF fibroblasts secrete pro-apoptotic molecules (both from extrinsic and intrinsic pathways), generating a microenvironment that induces apoptosis of T cells at 3 h of culture, despite a weak anti-apoptotic profile exhibited by these T cells. At 24 h of culture, the supernatants from both IPF and control fibroblasts provoked T-cell death. However, at this time of culture, IPF fibroblasts caused a marked decrease in T-cell migration; in contrast, control lung fibroblasts induced an increase of T-cell migration. The reduction of T-cell migratory capacity provoked by IPF fibroblasts was associated with a negative regulation of RHOA and ROCK, two essential GTPases for migration, and was independent of the expression of chemokine receptors. In conclusion, our findings demonstrate that IPF fibroblasts/myofibroblasts induce apoptosis and affect T-cell migration, revealing a mechanism involved in the virtual absence of T lymphocytes inside the FF.
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Fibrose Pulmonar Idiopática , Apoptose , Fibroblastos/metabolismo , Humanos , Fibrose Pulmonar Idiopática/metabolismo , Miofibroblastos/metabolismo , Linfócitos T/metabolismoRESUMO
Exposure to air pollutants in wildfire smoke and indoor pollution causes lung diseases. Short-term exposure to wood smoke (WS) is partially known to alter the expression of human matrix metalloproteinases (MMPs), inflammatory cytokines, and tissue inhibitors of metalloproteinases (TIMPs). Accordingly, we investigated the effect of exposing guinea pigs to WS for two and four three-hour periods on different days. The daily content of particles reported by indoor pollution was produced by 60 g of pinewood. We analyzed the cell profile and collagen content in bronchoalveolar lavages (BAL). The mRNA expression of pro-inflammatory cytokines, MMPs, and TIMPs was studied in lung tissue. Cytokines and gelatinolytic activity were analyzed in BAL and serum. The results showed that total cells, macrophages, neutrophils, and collagen increased in BAL, whereas neutrophils and lymphocytes decreased. TGF-ß1, TNF-α, IFN-γ, IL-1ß, IL-6, IL-8, MMP-2, MMP-9, TIMP-1, and TIMP-2 were upregulated in lungs, downregulating IL-12. TNF-α, IFN-γ, TGF-ß1, IL-1ß, IL-6, and IL-8 were increased in BAL and serum, decreasing IL-12. Gelatinase activity was increased in serum. Thus, guinea pigs exposed to short-term domestic doses of WS overexpressed pro-inflammatory cytokines, MMPs, and TIMPs. These results are similar to ECM remodeling and pulmonary and systemic inflammation reported in humans.
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. In passages above ten and growing very actively, we observed that some human lung fibroblasts cultured under standard conditions were transformed into a lineage of epithelial-like cells (ELC). To systematically evaluate the possible mesenchymal-epithelial transition (MET) occurrence, fibroblasts were obtained from normal lungs and also from lungs affected by idiopathic interstitial diseases. When an unusual epithelial-like phenotypic change was observed, cultured cells were characterized by confocal immunofluorescence microscopy, immunoblotting, immunocytochemistry, cytofluorometry, gelatin zymography, RT-qPCR, and hybridization in a whole-transcript human microarray. Additionally, microvesicles fraction (MVs) from ELC and fibroblasts were used to induce MET, while the microRNAs (miRNAs) contained in the MVs were identified. Pattern-gene expression of the original fibroblasts and the derived ELC revealed profound changes, upregulating characteristic epithelial-cell genes and downregulating mesenchymal genes, with a marked increase of E-cadherin, cytokeratin, and ZO-1, and the loss of expression of α-SMA, collagen type I, and Thy-1 cell surface antigen (CD90). Fibroblasts, exposed to culture media or MVs from the ELC, acquired ELC phenotype. The miRNAs in MVs shown six expressed exclusively in fibroblasts, and three only in ELC; moreover, twelve miRNAs were differentially expressed between fibroblasts and ELC, all of them but one was overexpressed in fibroblasts. These findings suggest that the MET-like process can occur in human lung fibroblasts, either from normal or diseased lungs. However, the biological implication is unclear.
Assuntos
Transição Epitelial-Mesenquimal , Fibroblastos/patologia , Doenças Pulmonares Intersticiais/patologia , Pulmão/patologia , Actinas/metabolismo , Idoso , Biomarcadores/metabolismo , Micropartículas Derivadas de Células/metabolismo , Células Cultivadas , Análise por Conglomerados , Colágeno Tipo I/metabolismo , Regulação para Baixo , Células Epiteliais/metabolismo , Células Epiteliais/patologia , Transição Epitelial-Mesenquimal/genética , Fibroblastos/metabolismo , Humanos , Doenças Pulmonares Intersticiais/metabolismo , Masculino , Metaloproteinase 2 da Matriz/metabolismo , Metaloproteinase 9 da Matriz/metabolismo , MicroRNAs/genética , MicroRNAs/metabolismo , Fenótipo , Antígenos Thy-1/metabolismoRESUMO
Idiopathic pulmonary fibrosis (IPF) is a progressive and lethal lung disease characterized by the expansion of the fibroblast/myofibroblast population and aberrant remodeling. However, the origin of mesenchymal cells in this disorder is still under debate. Recent evidence indicates that epithelial-mesenchymal transition (EMT) induced primarily by TGF-beta1 plays an important role; however, studies regarding the opposite process, mesenchymal-epithelial transition, are scanty. We have previously shown that fibroblast growth factor-1 (FGF-1) inhibits several profibrogenic effects of TGF-beta1. In this study, we examined the effects of FGF-1 on TGF-beta1-induced EMT. A549 and RLE-6TN (human and rat) alveolar epithelial-like cell lines were stimulated with TGF-beta1 for 72 h, and then, in the presence of TGF-beta1, were cultured with FGF-1 plus heparin for an additional 48 h. After TGF-beta1 treatment, epithelial cells acquired a spindle-like mesenchymal phenotype with a substantial reduction of E-cadherin and cytokeratins and concurrent induction of alpha-smooth muscle actin measured by real-time PCR, Western blotting, and immunocytochemistry. FGF-1 plus heparin reversed these morphological changes and returned the epithelial and mesenchymal markers to control levels. Signaling pathways analyzed by selective pharmacological inhibitors showed that TGF-beta1 induces EMT through Smad pathway, while reversion by FGF-1 occurs through MAPK/ERK kinase pathway, resulting in ERK-1 phosphorylation and Smad2 dephosphorylation. These findings indicate that TGF-beta1-induced EMT is reversed by FGF-1 and suggest therapeutic approaches to target this process in IPF.
Assuntos
Transdiferenciação Celular/efeitos dos fármacos , Células Epiteliais/fisiologia , Fator 1 de Crescimento de Fibroblastos/farmacologia , Mesoderma/fisiologia , Fator de Crescimento Transformador beta1/farmacologia , Animais , Células Cultivadas , Células Epiteliais/efeitos dos fármacos , Humanos , Fibrose Pulmonar Idiopática/etiologia , Fibrose Pulmonar Idiopática/patologia , Metaloproteinase 2 da Matriz/biossíntese , Metaloproteinase 9 da Matriz/biossíntese , Mesoderma/efeitos dos fármacos , Microscopia de Fluorescência , Quinases de Proteína Quinase Ativadas por Mitógeno/fisiologia , Fosforilação , Ratos , Transdução de Sinais , Proteína Smad2/metabolismo , Fator de Crescimento Transformador beta1/antagonistas & inibidoresRESUMO
Tobacco smoking is the primary risk factor for chronic obstructive pulmonary disease (COPD). However, recent epidemiological studies have established domestic exposure to wood smoke and other biomass fuels as additional important risk factors, characteristic in developing countries. Oxidative stress is one of the mechanisms concerned with pathogenesis of COPD. However, the molecular mechanisms involved in the onset and progress of COPD associated with biomass and specifically that derived from wood smoke exposure remain unknown. We analyzed the relationship between forced expiratory volume in first second (FEV(1)) with plasma malondialdehyde (MDA) concentration and activities of superoxide dismutase (SOD), glutathione peroxidase (GPx), glutathione reductase (GR), and glutathione-S-transferase (GST) in COPD patients associated with wood smoke (WSG; n = 30), tobacco smoking (TSG; n = 30), and healthy control subjects (HCG; n = 30). Differences between FEV(1) from WSG and TSG (58 +/- 22% and 51 +/- 24%, respectively) with HCG (100 +/- 6%) were observed (P < 0.01). Plasma MDA concentration was higher in both WSG and TSG (1.87 +/- 0.81 and 1.68 +/- 0.82 nmol/mL, respectively) compared with HCG (0.42 +/- 0.17 nmol/mL; P < 0.01). SOD activity showed a significant increase in both WSG and TSG (0.36 +/- 0.12 and 0.37 +/- 0.13 U/mL) compared with HCG (0.19 +/- 0.04 U/mL; P < 0.01). No differences were shown regarding GPx, GR, and GST activities between COPD and control groups. Inverse correlations were founded between MDA and SOD with FEV(1) in both COPD patients and control subjects (P < 0.001). These results indicate a role for oxidative stress in COPD associated with wood smoke similar to that observed with tobacco smoking in subjects who ceased at least 10 years previous to this study.
Assuntos
Nicotiana , Estresse Oxidativo/efeitos dos fármacos , Doença Pulmonar Obstrutiva Crônica/etiologia , Lesão por Inalação de Fumaça/induzido quimicamente , Fumaça/efeitos adversos , Madeira , Idoso , Feminino , Volume Expiratório Forçado/efeitos dos fármacos , Volume Expiratório Forçado/fisiologia , Humanos , Malondialdeído/sangue , Doença Pulmonar Obstrutiva Crônica/metabolismo , Doença Pulmonar Obstrutiva Crônica/fisiopatologia , Lesão por Inalação de Fumaça/sangue , Lesão por Inalação de Fumaça/fisiopatologia , Abandono do Hábito de Fumar , Superóxido Dismutase/sangueRESUMO
Idiopathic pulmonary fibrosis (IPF) is a progressive and lethal lung disorder of unknown etiology. IPF is likely the result of complex interrelationships between environmental and host factors, although the genetic risk factors are presently uncertain. Because we have found that some MHC polymorphisms confer susceptibility to IPF, in the present study we aimed to evaluate the role of the MHC class I chain-related gene A (MICA) in the risk of developing the disease. MICA molecular typing was done by reference strand mediated conformation analysis in a cohort of 80 IPF patients and 201 controls. In addition, the lung cellular source of the protein was examined by immunohistochemistry, the expression of the MICA receptor NKG2D in lung cells by flow cytometry and soluble MICA by ELISA. A significant increase of MICA*001 was observed in the IPF cohort (OR = 2.91, 95% CI = 1.04-8.25; pC = 0.03). Likewise, the frequency of the MICA*001/*00201 genotype was significantly increased in patients with IPF compared with the healthy controls (OR = 4.72, 95% CI = 1.15-22.51; pC = 0.01). Strong immunoreactive MICA staining was localized in alveolar epithelial cells and fibroblasts from IPF lungs while control lungs were negative. Soluble MICA was detected in 35% of IPF patients compared with 12% of control subjects (P = 0.0007). The expression of NKG2D was significantly decreased in gammadelta T cells and natural killer cells obtained from IPF lungs. These findings indicate that MICA polymorphisms and abnormal expression of the MICA receptor NKG2D might contribute to IPF susceptibility.