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1.
Medicine (Baltimore) ; 99(12): e19650, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32195974

RESUMO

RATIONALE: Mutations of the NKX2-1 gene are associated with brain-lung-thyroid syndrome, which is characterized by benign hereditary chorea, hypothyroidism, and pulmonary disease with variable presentation. Surfactant protein C (SFTPC) gene mutations result in chronic interstitial lung disease in adults or severe neonatal respiratory distress syndrome. PATIENT CONCERNS: Recurrent hypoxemia was observed shortly after birth in a baby at a gestational age of 40 weeks and birth weight of 3150 g. The need for respiratory support gradually increased. He had hypothyroidism and experienced feeding difficulties and irritability. DIAGNOSIS: Genetic examination of the peripheral blood revealed combined mutations of the NKX2-1 and SFTPC genes. INTERVENTIONS: The patient was administered respiratory support, antibiotics, low-dose dexamethasone, supplementary thyroxine, venous nutrition, and other supportive measures. OUTCOMES: The patient's guardian stopped treatment 3 months after commencement of treatment, due to the seriousness of his condition and the patient died. LESSONS: Combined mutations of NKX2-1 and SFTPC genes are very rare. Thus, idiopathic interstitial pneumonia with hypothyroidism and neurological disorders require special attention.


Assuntos
Atetose/genética , Coreia/genética , Hipotireoidismo Congênito/genética , Proteína C/metabolismo , Surfactantes Pulmonares/metabolismo , Síndrome do Desconforto Respiratório do Recém-Nascido/genética , Fator Nuclear 1 de Tireoide/genética , Atetose/sangue , Atetose/diagnóstico , Atetose/terapia , Coreia/sangue , Coreia/diagnóstico , Coreia/terapia , Hipotireoidismo Congênito/sangue , Hipotireoidismo Congênito/diagnóstico , Hipotireoidismo Congênito/terapia , Evolução Fatal , Transtornos da Alimentação e da Ingestão de Alimentos/diagnóstico , Transtornos da Alimentação e da Ingestão de Alimentos/etiologia , Humanos , Hipotireoidismo/diagnóstico , Hipotireoidismo/etiologia , Hipóxia/diagnóstico , Hipóxia/etiologia , Recém-Nascido , Cariotipagem , Doenças Pulmonares Intersticiais/diagnóstico , Doenças Pulmonares Intersticiais/etiologia , Masculino , Mutação , Cuidados Paliativos/métodos , Recidiva , Síndrome do Desconforto Respiratório do Recém-Nascido/sangue , Síndrome do Desconforto Respiratório do Recém-Nascido/diagnóstico , Síndrome do Desconforto Respiratório do Recém-Nascido/etiologia , Síndrome do Desconforto Respiratório do Recém-Nascido/terapia
2.
PLoS One ; 15(2): e0228279, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32027677

RESUMO

Smoke exposure is known to decrease total pulmonary surfactant and alter its composition, but the role of surfactant in chronic obstructive pulmonary disease (COPD) remains unknown. We aimed to analyze the compositional changes in the surfactant lipidome in COPD and identify specific lipids associated with pulmonary function decline. Bronchoalveolar lavage (BAL) fluid was obtained from 12 former smokers with COPD and 5 non-smoking, non-asthmatic healthy control volunteers. Lipids were extracted and analyzed by liquid chromatography and mass spectrometry. Pulmonary function data were obtained by spirometry, and correlations of lung function with lipid species were determined. Wild-type C57BL/6 mice were exposed to 6 months of second-hand smoke in a full-body chamber. Surfactant lipids were decreased by 60% in subjects with COPD. All phospholipid classes were dramatically decreased, including ether phospholipids, which have not been studied in pulmonary surfactant. Availability of phospholipid, cholesterol, and sphingomyelin in BAL strongly correlated with pulmonary function and this was attributable to specific lipid species of phosphatidylcholine with surface tension reducing properties, and of phosphatidylglycerol with antimicrobial roles, as well as to other less studied lipid species. Mice exposed to smoke for six months recapitulated surfactant lipidomic changes observed in human subjects with COPD. In summary, we show that the surfactant lipidome is substantially altered in subjects with COPD, and decreased availability of phospholipids correlated with decreased pulmonary function. Further investigation of surfactant alterations in COPD would improve our understanding of its physiopathology and reveal new potential therapeutic targets.


Assuntos
Lipídeos/análise , Pulmão/metabolismo , Doença Pulmonar Obstrutiva Crônica/fisiopatologia , Surfactantes Pulmonares/metabolismo , Idoso , Animais , Líquido da Lavagem Broncoalveolar/química , Estudos de Casos e Controles , Cromatografia Líquida de Alta Pressão , Modelos Animais de Doenças , Humanos , Espectrometria de Massas , Camundongos , Camundongos Endogâmicos C57BL , Pessoa de Meia-Idade , Fosfatidilcolinas/química , Fosfatidilcolinas/metabolismo , Fosfolipídeos/química , Fosfolipídeos/metabolismo , Fumantes , Poluição por Fumaça de Tabaco
3.
Toxicol In Vitro ; 62: 104656, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31536757

RESUMO

The toxicity of some per- and polyfluoroalkyl substances (PFASs), such as perfluorooctane sulfonate (PFOS) and perfluorooctanoic acid (PFOA) has been studied thoroughly, showing that systemic PFASs targets the lungs. However, regulators lack data to assess the impact of other PFASs on the lungs and alternative methods to test substances for lung toxicity are needed. We combined two in vitro models to assess toxicity to the respiratory system; i) a lung surfactant (LS) function assay to assess the acute inhalation toxicity potential, and ii) a cell model with human bronchial epithelial cells to study pro-inflammatory potential and modulation of inflammatory responses. We tested salts of four PFASs: perfluorobutane sulfonate (PFBS), perfluorohexane sulfonate (PFHxS), PFOS, and PFOA as well as the fluorotelomer 8:2 FTOH. The results show that PFHxS, PFOA and PFOS can inhibit LS function. High PFOS concentrations induced a pro-inflammatory response, measured as increased IL-1α/ß release. Moderate concentrations of PFOS suppressed release of the chemokines CXCL8 and CXCL10, whereas both PFOS and PFOA stimulated the release of the pro-inflammatory cytokine IL-1ß in immune stimulated human bronchial epithelial cells. These findings support the concern that some PFASs may increase the risk of acute lung toxicity and of airway infections.


Assuntos
Ácidos Alcanossulfônicos/toxicidade , Caprilatos/toxicidade , Citocinas/metabolismo , Fluorcarbonetos/toxicidade , Surfactantes Pulmonares/metabolismo , Brônquios/citologia , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Humanos
4.
Environ Toxicol ; 35(1): 27-36, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31498972

RESUMO

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 ICR
5.
Ecotoxicol Environ Saf ; 186: 109770, 2019 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-31606643

RESUMO

Cultured human lung epithelial cells, particularly A549 cells, are commonly used as the in vitro model to evaluate the inhalational toxicity of nanoparticles (NPs). However, A549 cells are cancer cells that might not reflect the response of normal tissues to NP exposure. In addition, the possible influence of pulmonary surfactant also should be considered. This study used silica NPs as model NPs, and evaluated the toxicity of silica NPs to both 16HBE human bronchial epithelial cells and A549 adenocarcinomic cells, with or without the presence of pulmonary surfactant component dipalmitoyl phosphatidylcholine (DPPC). We found that silica NPs induced cytotoxicity at the concentration of 128 µg/mL in 16HBE cells but not A5490 cells, and the cytotoxicity of silica NPs to 16HBE cells was inhibited by DPPC. Intracellular reactive oxygen species (ROS) was only induced in 16HBE cells, accompanying with decreased thiol levels. Moreover, 16HBE cells internalized more silica NPs compared with A549 cells, and the internalization was reduced with the presence of DPPC in both types of cells. The retention of ABC transporter substrate Calcein was only significantly induced by silica NPs at high concentrations in 16HBE cells, and was partially reduced due to the presence of DPPC. In addition, ABC transporter inhibitor MK571 increased the toxicity of silica NPs to both types of cells, with 16HBE cells being more sensitive. Our data revealed that the cell types and pulmonary surfactant components could influence the toxicological consequences of silica NPs to human lung cells. Therefore, it is recommended that in vitro studies should carefully select suitable models to evaluate the inhalational toxicity of NPs.


Assuntos
1,2-Dipalmitoilfosfatidilcolina/metabolismo , Células Epiteliais/efeitos dos fármacos , Pulmão/efeitos dos fármacos , Nanopartículas/toxicidade , Surfactantes Pulmonares/metabolismo , Dióxido de Silício/toxicidade , 1,2-Dipalmitoilfosfatidilcolina/análogos & derivados , Células A549 , Sobrevivência Celular/efeitos dos fármacos , Células Epiteliais/metabolismo , Humanos , Pulmão/metabolismo , Espécies Reativas de Oxigênio/metabolismo
6.
Eur J Pharm Biopharm ; 144: 230-243, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31560956

RESUMO

The rapid development of nanotechnology is opening a huge world of promising possibilities in healthcare, but this is also increasing the necessity to study the potential risk of nanoparticles on public health and the environment. Since the main route for airborne particles to enter into our organism is through the lungs, it has become essential to prove that the nanoparticles generated by human activities do not compromise the respiratory function. This review explains the key role of pulmonary surfactant to sustain the normal function of breathing, as well as the stability and immunity of lungs. Particular emphasis is made on the importance of analysing the features of nanoparticles, defining their interactions with surfactant and unravelling the mutual effects. The implication of the nanoparticle-surfactant interaction on the function and fate of both structures is described, as well as the main in vitro methodologies used to evaluate this interaction. Finally, the incorporation of pulmonary surfactant in appropriate in vitro models is used in order to obtain an extensive understanding of how nanoparticles may act in the context of the lung. The main goal of this review is to offer a general view on inhaled nanoparticles and their effects on the structure and function of lungs derived from their interaction with the pulmonary surfactant system.


Assuntos
Pulmão/metabolismo , Nanopartículas/metabolismo , Surfactantes Pulmonares/metabolismo , Administração por Inalação , Animais , Sistemas de Liberação de Medicamentos/métodos , Humanos , Interações Hidrofóbicas e Hidrofílicas , Lipoproteínas/metabolismo , Nanotecnologia/métodos
7.
Respir Res ; 20(1): 175, 2019 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-31382955

RESUMO

BACKGROUND: The amount of surfactant deposited in the lungs and its overall pulmonary distribution determine the therapeutic outcome of surfactant replacement therapy. Most of the currently available methods to determine the intrapulmonary distribution of surfactant are time-consuming and require surfactant labelling. Our aim was to assess the potential of Mass Spectrometry Imaging (MSI) as a label-free technique to qualitatively and quantitatively evaluate the distribution of surfactant to the premature lamb. METHODS: Twelve preterm lambs (gestational age 126-127d, term ~150d) were allocated in two experimental groups. Seven lambs were treated with an intratracheal bolus of the synthetic surfactant CHF5633 (200 mg/kg) and 5 lambs were managed with mechanical ventilation for 120 min, as controls. The right lung lobes of all lambs were gradually frozen while inflated to 20 cmH2O pressure for lung cryo-sections for MSI analysis. The intensity signals of SP-C analog and SP-B analog, the two synthetic peptides contained in the CHF5633 surfactant, were used to locate, map and quantify the intrapulmonary exogenous surfactant. RESULTS: Surfactant treatment was associated with a significant improvement of the mean arterial oxygenation and lung compliance (p < 0.05). Nevertheless, the physiological response to surfactant treatment was not uniform across all animals. SP-C analog and SP-B analog were successfully imaged and quantified by means of MSI in the peripheral lungs of all surfactant-treated animals. The intensity of the signal was remarkably low in untreated lambs, corresponding to background noise. The signal intensity of SP-B analog in each surfactant-treated animal, which represents the surfactant distributed to the peripheral right lung, correlated well with the physiologic response as assessed by the area under the curves of the individual arterial partial oxygen pressure and dynamic lung compliance curves of the lambs. CONCLUSIONS: Applying MSI, we were able to detect, locate and quantify the amount of exogenous surfactant distributed to the lower right lung of surfactant-treated lambs. The distribution pattern of SP-B analog correlated well with the pulmonary physiological outcomes of the animals. MSI is a valuable label-free technique which is able to simultaneously evaluate qualitative and quantitative drug distribution in the lung.


Assuntos
Pulmão/metabolismo , Fragmentos de Peptídeos/análise , Fragmentos de Peptídeos/metabolismo , Fosfatidilcolinas/análise , Fosfatidilcolinas/metabolismo , Proteína B Associada a Surfactante Pulmonar/análise , Proteína B Associada a Surfactante Pulmonar/metabolismo , Proteína C Associada a Surfactante Pulmonar/análise , Proteína C Associada a Surfactante Pulmonar/metabolismo , Surfactantes Pulmonares/análise , Surfactantes Pulmonares/metabolismo , Animais , Animais Recém-Nascidos , Pulmão/efeitos dos fármacos , Espectrometria de Massas/métodos , Fragmentos de Peptídeos/farmacologia , Fosfatidilcolinas/farmacologia , Proteína B Associada a Surfactante Pulmonar/farmacologia , Proteína C Associada a Surfactante Pulmonar/farmacologia , Surfactantes Pulmonares/farmacologia , Ovinos , Distribuição Tecidual
8.
Respir Res ; 20(1): 158, 2019 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-31319861

RESUMO

BACKGROUND: Respiratory Distress Syndrome (RDS) is a prematurity-related breathing disorder caused by a quantitative deficiency of pulmonary surfactant. Surfactant replacement therapy is effective for RDS newborns, although treatment failure has been reported. The aim of this study is to trace exogenous surfactant by 13C variation and estimate the amount reaching the lungs at different doses of the drug. METHODS: Forty-four surfactant-depleted rabbits were obtained by serial bronchoalveolar lavages (BALs), that were merged into a pool (BAL pool) for each animal. Rabbits were in nasal continuous positive airway pressure and treated with 0, 25, 50, 100 or 200 mg/kg of poractant alfa by InSurE. After 90 min, rabbits were depleted again and a new pool (BAL end experiment) was collected. Disaturated-phosphatidylcholine (DSPC) was measured by gas chromatography. DSPC-Palmitic acid (PA) 13C/12C was analyzed by isotope ratio mass spectrometry. One-way non-parametric ANOVA and post-hoc Dunn's multiple comparison were used to assess differences among experimental groups. RESULTS: Based on DSPC-PA 13C/12C in BAL pool and BAL end experiment, the estimated amount of exogenous surfactant ranged from 61 to 87% in dose-dependent way (p < 0.0001) in animals treated with 25 up to 200 mg/kg. Surfactant administration stimulated endogenous surfactant secretion. The percentage of drug recovered from lungs did not depend on the administered dose and accounted for 31% [24-40] of dose. CONCLUSIONS: We reported a risk-free method to trace exogenous surfactant in vivo. It could be a valuable tool for assessing, alongside the physiological response, the delivery efficiency of surfactant administration techniques.


Assuntos
Produtos Biológicos/metabolismo , Isótopos de Carbono/metabolismo , Pulmão/metabolismo , Fosfolipídeos/metabolismo , Surfactantes Pulmonares/metabolismo , Animais , Produtos Biológicos/administração & dosagem , Isótopos de Carbono/administração & dosagem , Relação Dose-Resposta a Droga , Pulmão/efeitos dos fármacos , Masculino , Fosfolipídeos/administração & dosagem , Surfactantes Pulmonares/administração & dosagem , Coelhos , Tensoativos/administração & dosagem , Tensoativos/metabolismo
9.
Respir Res ; 20(1): 134, 2019 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-31266508

RESUMO

BACKGROUND: Non-invasive delivery of nebulized surfactant has been a neonatology long-pursued goal. Nevertheless, the clinical efficacy of nebulized surfactant remains inconclusive, in part, due to the great technical challenges of depositing nebulized drugs in the lungs of preterm infants. The aim of this study was to investigate the feasibility of delivering nebulized surfactant (poractant alfa) in vitro and in vivo with an adapted, neonate-tailored aerosol delivery strategy. METHODS: Particle size distribution of undiluted poractant alfa aerosols generated by a customized eFlow-Neos nebulizer system was determined by laser diffraction. The theoretical nebulized surfactant lung dose was estimated in vitro in a clinical setting replica including a neonatal continuous positive airway pressure (CPAP) circuit, a cast of the upper airways of a preterm neonate, and a breath simulator programmed with the tidal breathing pattern of an infant with mild respiratory distress syndrome (RDS). A dose-response study with nebulized surfactant covering the 100-600 mg/kg nominal dose-range was conducted in RDS-modelling, lung-lavaged spontaneously-breathing rabbits managed with nasal CPAP. The effects of nebulized poractant alfa on arterial gas exchange and lung mechanics were assessed. Exogenous alveolar disaturated-phosphatidylcholine (DSPC) in the lungs was measured as a proxy of surfactant deposition efficacy. RESULTS: Laser diffraction studies demonstrated suitable aerosol characteristics for inhalation (mass median diameter, MMD = 3 µm). The mean surfactant lung dose determined in vitro was 13.7% ± 4.0 of the 200 mg/kg nominal dose. Nebulized surfactant delivered to spontaneously-breathing rabbits during nasal CPAP significantly improved arterial oxygenation compared to animals receiving CPAP only. Particularly, the groups of animals treated with 200 mg/kg and 400 mg/kg of nebulized poractant alfa achieved an equivalent pulmonary response in terms of oxygenation and lung mechanics as the group of animals treated with instilled surfactant (200 mg/kg). CONCLUSIONS: The customized eFlow-Neos vibrating-membrane nebulizer system efficiently generated respirable aerosols of undiluted poractant alfa. Nebulized surfactant delivered at doses of 200 mg/kg and 400 mg/kg elicited a pulmonary response equivalent to that observed after treatment with an intratracheal surfactant bolus of 200 mg/kg. This bench-characterized nebulized surfactant delivery strategy is now under evaluation in Phase II clinical trial (EUDRACT No.:2016-004547-36).


Assuntos
Produtos Biológicos/administração & dosagem , Sistemas de Liberação de Medicamentos/métodos , Modelos Biológicos , Nebulizadores e Vaporizadores , Fosfolipídeos/administração & dosagem , Surfactantes Pulmonares/administração & dosagem , Animais , Produtos Biológicos/metabolismo , Humanos , Recém-Nascido , Pulmão/efeitos dos fármacos , Pulmão/metabolismo , Masculino , Tamanho da Partícula , Fosfolipídeos/metabolismo , Surfactantes Pulmonares/metabolismo , Coelhos
10.
Drug Deliv ; 26(1): 604-611, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31204848

RESUMO

Intra-tracheal instillation of budesonide using surfactant as a vehicle significantly decreased the incidence of bronchopulmonary dysplasia or death in preterm infants. The formularity of surfactant supplemented with budesonide and biophysical and chemical stability of the suspension has not been well reported. The aims are to investigate the biophysical and chemical stability of two surfactant preparations, Survanta and Curosurf, supplemented with budesonide. Biophysical property of the surface tension of Survanta and Survanta/budesonide suspension and of Curosurf and Curosurf/budesonide suspension was conducted by a pulsating bubble surfactometer and by a drop shape tensiometer. Chemical stability of Survanta/budesonide and of Curosurf/budesonide suspensions was tested by high-performance liquid chromatography analysis (HPLC). Pulmonary distribution of Survanta/18F-budesonide suspension was examined by a Nano/PET digital scan in rats. The Marangoni effect of Survanta, Curosurf, and budesonide was tested by digital high speed photography. For Survanta supplemented with budesonide, with a concentration ratio of ≥50, the surface tension-lowering activity was minimally affected. Similarly, the surface tension-lowering activity of Curosurf was not significantly affected by addition of budesonide, if the concentration ratio was ≥160. With these concentration ratios of both suspensions, HPLC analysis revealed no new compounds identified. Curosurf as compared to Survanta exhibited a significantly higher Marangoni effect. We conclude that with current dosage recommended for Survanta and Curosurf, both surfactant/budesonide suspensions are biophysically and chemically stable. Both surfactants can act as an effective vehicle for budesonide delivery.


Assuntos
Budesonida/química , Budesonida/metabolismo , Pulmão/metabolismo , Surfactantes Pulmonares/química , Surfactantes Pulmonares/metabolismo , Animais , Produtos Biológicos/química , Produtos Biológicos/metabolismo , Injeção Intratimpânica/métodos , Masculino , Fosfolipídeos/química , Fosfolipídeos/metabolismo , Ratos , Ratos Sprague-Dawley , Tensão Superficial/efeitos dos fármacos
11.
Respir Res ; 20(1): 75, 2019 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-30992006

RESUMO

BACKGROUND: It is not known if the endogenous surfactant pool available early in life is associated with the RDS clinical course in preterm neonates treated with CPAP. We aim to clarify the clinical factors affecting surfactant pool in preterm neonates and study its association with CPAP failure. METHODS: Prospective, pragmatic, blind, cohort study. Gastric aspirates were obtained (within the first 6 h of life and before the first feeding) from 125 preterm neonates with RDS. Surfactant pool was measured by postnatal automated lamellar body count based on impedancemetry, without any pre-analytical treatment. A formal respiratory care protocol based on European guidelines was applied. Clinical data and perinatal risk factors influencing RDS severity or lamellar body count were real-time recorded. Investigators performing lamellar body count were blind to the clinical data and LBC was not used in clinical practice. RESULTS: Multivariate analysis showed gestational age to be the only factor significantly associated with lamellar body count (standardized ß:0.233;p = 0.023). Lamellar body count was significantly higher in neonates with CPAP success (43.500 [23.750-93.750]bodies/µL), than in those failing CPAP (20.500 [12.250-49.750] bodies/µL;p = 0.0003).LBC had a moderate reliability to detect CPAP failure (AUC: 0.703 (0.615-0.781);p < 0.0001; best cut-off: ≤30,000 bodies/µL). Upon adjustment for possible confounders, neither lamellar body count, nor its interaction factor with gestational age resulted associated with CPAP failure. CONCLUSIONS: Early postnatal lamellar body count on gastric aspirates in CPAP-treated preterm neonates with RDS is significantly influenced only by gestational age. Lamellar bodies are not associated with CPAP failure. Thus, the endogenous surfactant pool available early in life only has a moderate reliability to predict CPAP failure.


Assuntos
Pressão Positiva Contínua nas Vias Aéreas/tendências , Recém-Nascido Prematuro/metabolismo , Surfactantes Pulmonares/metabolismo , Síndrome do Desconforto Respiratório do Recém-Nascido/metabolismo , Síndrome do Desconforto Respiratório do Recém-Nascido/terapia , Estudos de Coortes , Feminino , Idade Gestacional , Humanos , Recém-Nascido , Masculino , Gravidez , Estudos Prospectivos , Surfactantes Pulmonares/análise , Método Simples-Cego , Falha de Tratamento
12.
Cell Mol Biol Lett ; 24: 25, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30988675

RESUMO

Background: Pulmonary surfactant is the complex mixture of lipid and protein that covers the alveolar surface. Pulmonary surfactant deficiency is one of the main causes of neonatal respiratory distress. Recent studies showed that miRNA plays an important role in lung development, but research into miR-431 regulation of pulmonary surfactant are sparse. In this study, we explored the regulatory role of miR-431-5p in the expression of pulmonary surfactant and identified its potential target gene, Smad4. Methods: The bioinformatics tool TargetScan was used to predict the targets of miR-431. The expression of miR-431-5p was achieved via transfection of miR-431-5p mimics, an miR-431-5p inhibitor and corresponding negative control. The level of miR-431-5p was determined using quantitative real-time PCR. The CCK8 assay was conducted to confirm cell growth 12 h after transfection with miR-431-5p mimics, inhibitor or NC. Smad4 and surfactant-associated proteins in A549 were analyzed using western blot and quantitative real-time PCR. Results: Smad4 was validated as a target of miR-431 in A549 cells. Overexpression of miR-431 accelerated A549 proliferation and inhibited A549 apoptosis. The mRNA and protein levels for the surfactant proteins (SP-A, SP-B, SP-C and SP-D) were found to be differentially expressed in A549 cells over- or under-expressing miR-431-5p. Conclusion: Our results show that miR-431-5p is critical for pulmonary surfactant expression and that its regulation is closely related to the TGF-ß/Smad4 pathway. These results will help us to study the pathophysiological mechanism of lung developmental diseases.


Assuntos
MicroRNAs/metabolismo , Surfactantes Pulmonares/metabolismo , Regiões 3' não Traduzidas/genética , Células A549 , Apoptose/genética , Sequência de Bases , Proliferação de Células/genética , Humanos , MicroRNAs/genética , Proteína Smad4/metabolismo
13.
PLoS One ; 14(4): e0215611, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31002676

RESUMO

Limited information is available on how fetal growth retardation (FGR) affects the lung in the neonatal period in males and females. This led us to test the hypothesis that FGR alters lung mechanics and the surfactant system during the neonatal period. To test this hypothesis a model of FGR was utilized in which pregnant rat dams were fed a low protein diet during both the gestation and lactation period. We subsequently analyzed lung mechanics using a FlexiVent ventilator in male and female pups at postnatal day 7 and 21. Lung lavage material was obtained at postnatal day 1, 7 and 21, and was used for analysis of the surfactant system which included measurement of the pool size of surfactant and its subfraction as well as the surface tension reducing ability of the surfactant. The main result of the study was a significantly lower lung compliance and higher tissue elastance which was observed in FGR female offspring at day 21 compared to control offspring. In addition, female LP offspring exhibited lower surfactant pool sizes at postnatal day 1compared to controls. These changes were not observed in the male offspring. It is concluded that FGR has a different impact on pulmonary function and on surfactant in female, as compared to male, offspring.


Assuntos
Fenômenos Fisiológicos da Nutrição Animal/fisiologia , Dieta com Restrição de Proteínas/efeitos adversos , Retardo do Crescimento Fetal/fisiopatologia , Surfactantes Pulmonares/metabolismo , Mecânica Respiratória/fisiologia , Animais , Animais Recém-Nascidos , Feminino , Retardo do Crescimento Fetal/etiologia , Lactação , Pulmão/crescimento & desenvolvimento , Pulmão/metabolismo , Pulmão/fisiopatologia , Masculino , Gravidez , Ratos Wistar , Fatores Sexuais
14.
J Surg Res ; 239: 242-252, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-30856517

RESUMO

BACKGROUND: Understanding inconsistent clinical outcomes in infants with severe congenital diaphragmatic hernia (CDH) after tracheal occlusion (TO) is a crucial step for advancing neonatal care. The objective of this study is to explore the heterogeneous airspace morphometry and the metabolic landscape changes in fetal lungs after TO. METHODS: Fetal lungs on days 1 and 4 after TO were examined using mass spectrometry-based metabolomics, fluorescence lifetime imaging microscopy (FLIM), the number of airspaces, and tissue-to-airspace ratio (TAR). RESULTS: Two morphometric areas were identified in TO lungs compared with controls (more small airspaces at day 1 and a higher number of enlarged airspaces at day 4). Global metabolomics analysis revealed a significant upregulation of glycolysis and a suppression of the tricarboxylic acid cycle in day 4 TO lungs compared with day 1 TO lungs. In addition, there was a significant increase in polyamines involved in cell growth and proliferation. Locally, FLIM analysis on day 1 TO lungs demonstrated two types of heterogeneous zones-similar to control and with increased oxidative phosphorylation. FLIM on day 4 TO lungs demonstrated appearance of zones with enlarged airspaces and a metabolic shift toward glycolysis, accompanied by a decrease in the FLIM "lipid-surfactant" signal. CONCLUSIONS: In normal fetal lungs, we report a novel temporal pattern of varied morphometric and metabolic changes. Initially, there is formation of zones with small airspaces, followed by airspace enlargement over time. Metabolically day 1 TO lungs have zones with increased oxidative phosphorylation, whereas day 4 TO lungs have a shift toward glycolysis in the enlarged airspaces. Based on our observations, we speculate that the "best responders" to tracheal occlusion should have bigger lungs with small airspaces and normal surfactant production.


Assuntos
Obstrução das Vias Respiratórias/complicações , Feto/embriologia , Hérnias Diafragmáticas Congênitas/patologia , Pulmão/embriologia , Organogênese/fisiologia , Obstrução das Vias Respiratórias/metabolismo , Obstrução das Vias Respiratórias/patologia , Animais , Modelos Animais de Doenças , Feminino , Feto/metabolismo , Feto/patologia , Glicólise/fisiologia , Hérnias Diafragmáticas Congênitas/etiologia , Hérnias Diafragmáticas Congênitas/metabolismo , Humanos , Pulmão/metabolismo , Pulmão/patologia , Metabolômica , Tamanho do Órgão/fisiologia , Fosforilação Oxidativa , Gravidez , Surfactantes Pulmonares/metabolismo , Coelhos , Traqueia/cirurgia
15.
Nat Rev Dis Primers ; 5(1): 16, 2019 03 07.
Artigo em Inglês | MEDLINE | ID: mdl-30846703

RESUMO

Pulmonary alveolar proteinosis (PAP) is a syndrome characterized by the accumulation of alveolar surfactant and dysfunction of alveolar macrophages. PAP results in progressive dyspnoea of insidious onset, hypoxaemic respiratory failure, secondary infections and pulmonary fibrosis. PAP can be classified into different types on the basis of the pathogenetic mechanism: primary PAP is characterized by the disruption of granulocyte-macrophage colony-stimulating factor (GM-CSF) signalling and can be autoimmune (caused by elevated levels of GM-CSF autoantibodies) or hereditary (due to mutations in CSF2RA or CSF2RB, encoding GM-CSF receptor subunits); secondary PAP results from various underlying conditions; and congenital PAP is caused by mutations in genes involved in surfactant production. In most patients, pathogenesis is driven by reduced GM-CSF-dependent cholesterol clearance in alveolar macrophages, which impairs alveolar surfactant clearance. PAP has a prevalence of at least 7 cases per million individuals in large population studies and affects men, women and children of all ages, ethnicities and geographical locations irrespective of socioeconomic status, although it is more-prevalent in smokers. Autoimmune PAP accounts for >90% of all cases. Management aims at improving symptoms and quality of life; whole-lung lavage effectively removes excessive surfactant. Novel pathogenesis-based therapies are in development, targeting GM-CSF signalling, immune modulation and cholesterol homeostasis.


Assuntos
Proteinose Alveolar Pulmonar/diagnóstico , Proteinose Alveolar Pulmonar/terapia , Lavagem Broncoalveolar/métodos , Broncoscopia/métodos , Humanos , Proteinose Alveolar Pulmonar/epidemiologia , Fibrose Pulmonar/etiologia , Surfactantes Pulmonares/metabolismo , Qualidade de Vida/psicologia , Fatores de Risco , Tomografia Computadorizada por Raios X/métodos
16.
Am J Physiol Lung Cell Mol Physiol ; 316(4): L669-L678, 2019 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-30702343

RESUMO

Smoking alters pulmonary reverse lipid transport and leads to intracellular lipid accumulation in alveolar macrophages. We investigated whether stimulating reverse lipid transport with an agonist of the liver X receptor (LXR) would help alveolar macrophages limit lipid accumulation and dampen lung inflammation in response to cigarette smoke. Mice were exposed to cigarette smoke and treated intraperitoneally with the LXR agonist T0901317. Expression of lipid capture and lipid export genes was assessed in lung tissue and alveolar macrophages. Pulmonary inflammation was assessed in the bronchoalveolar lavage (BAL). Finally, cholesterol efflux capacity and pulmonary surfactant levels were determined. In room air-exposed mice, T0901317 increased the expression of lipid export genes in macrophages and the whole lung and increased cholesterol efflux capacity without inducing inflammation or affecting the pulmonary surfactant. However, cigarette smoke-exposed mice treated with T0901317 showed a marked increase in BAL neutrophils, IL-1α, C-C motif chemokine ligand 2, and granulocyte-colony-stimulating factor levels. T0901317 treatment in cigarette smoke-exposed mice failed to increase the ability of alveolar macrophages to export cholesterol and markedly exacerbated IL-1α release. Finally, T0901317 led to pulmonary surfactant depletion only in cigarette smoke-exposed mice. This study shows that hyperactivation of LXR and the associated lipid capture/export mechanisms only have minor pulmonary effects on the normal lung. However, in the context of cigarette smoke exposure, where the pulmonary surfactant is constantly oxidized, hyperactivation of LXR has dramatic adverse effects, once again showing the central role of lipid homeostasis in the pulmonary response to cigarette smoke exposure.


Assuntos
Receptores X do Fígado/agonistas , Macrófagos Alveolares/efeitos dos fármacos , Macrófagos Alveolares/metabolismo , Surfactantes Pulmonares/metabolismo , Fumaça/efeitos adversos , Tabaco/toxicidade , Animais , Fumar Cigarros/efeitos adversos , Fumar Cigarros/genética , Fumar Cigarros/metabolismo , Feminino , Expressão Gênica/efeitos dos fármacos , Homeostase/efeitos dos fármacos , Hidrocarbonetos Fluorados/farmacologia , Metabolismo dos Lipídeos/efeitos dos fármacos , Metabolismo dos Lipídeos/genética , Pulmão/efeitos dos fármacos , Pulmão/metabolismo , Macrófagos Alveolares/patologia , Camundongos , Camundongos Endogâmicos C57BL , Modelos Animais , Sulfonamidas/farmacologia
17.
Artigo em Inglês | MEDLINE | ID: mdl-30718243

RESUMO

The present study aimed to clarify the mechanism underlying the high distribution of lascufloxacin in epithelial lining fluid (ELF). Involvement of transporters was examined by transcellular transport across Calu-3 and transporter-overexpressing cells; the binding of lascufloxacin to ELF components was examined by an organic solvent-water partitioning system that employed pulmonary surfactant and phospholipids. Transcellular transport across the transporter-overexpressing cells indicated lascufloxacin to be a substrate of both P-glycoprotein (P-gp) and breast cancer resistance protein (BCRP); therefore, its transport across Calu-3 cells was inhibited by P-gp and BCRP inhibitors. However, permeability and efflux ratios of lascufloxacin were similar to those of the other quinolones with relatively low ELF distribution, indicating the existence of another mechanism for lascufloxacin distribution in ELF. Amongst pulmonary surfactants, which are a primary component of ELF, lascufloxacin preferentially bound to phosphatidylserine (PhS) from several phospholipids, and the binding was significantly greater than that for other quinolones. This binding was saturable with two apparent classes of binding sites and inhibited by some weakly basic drugs, indicating the presence of an ionic bond. In conclusion, the results of this study suggest that the binding of lascufloxacin to PhS in the pulmonary surfactant is the major mechanism of the high distribution of lascufloxacin in the ELF.


Assuntos
Células Epiteliais/metabolismo , Fluoroquinolonas/metabolismo , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/metabolismo , Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP/metabolismo , Transporte Biológico/fisiologia , Linhagem Celular , Humanos , Fosfatidilserinas/metabolismo , Fosfolipídeos/metabolismo , Surfactantes Pulmonares/metabolismo , Quinolonas/metabolismo
18.
Chemosphere ; 222: 603-610, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30731380

RESUMO

Understanding the interaction between pulmonary surfactant (PS) and inhalable pollutants is vital for risk assessment of respiratory health. Here, PS extracted from porcine lung (EPS) was used to investigate the interaction of PS with nano-silica particles and polycyclic aromatic hydrocarbons (PAHs). Our results demonstrated that silica significantly affected the phase behavior and foaming ability of EPS; EPS and its major components (dipalmitoyl phosphatidylcholine, DPPC; bovine serum albumin, BSA) exhibited great enhancing effect on PAHs solubility, which follows the order: EPS > DPPC > BSA, and it was positively correlated with the hydrophobicity of PAHs. Further experiments demonstrated that mixed phospholipids of EPS were largely responsible for the solubilization of EPS on PAHs. In the presence of EPS, DPPC or BSA, adsorption of PAHs by silica was notably inhibited, indicating competitive adsorption between PAHs and PS components on silica. These findings provide evidence for the surface chemistry by which PS facilitates the solubilization of PAHs and reducing the adsorption of PAHs on silica, which may be helpful for deeply understanding the effects of particulate matter and PAHs on lung health.


Assuntos
Hidrocarbonetos Policíclicos Aromáticos/metabolismo , Surfactantes Pulmonares/metabolismo , Sistema Respiratório/efeitos dos fármacos , Dióxido de Silício/metabolismo , Tensoativos/metabolismo , Adsorção , Animais , Surfactantes Pulmonares/efeitos adversos , Tensoativos/efeitos adversos , Suínos
19.
J Biol Chem ; 294(12): 4282-4289, 2019 03 22.
Artigo em Inglês | MEDLINE | ID: mdl-30733339

RESUMO

Toll-like receptors (TLRs) coupled to intracellular signaling cascades function as central elements of innate immunity that control transcription of numerous pro-inflammatory genes. Two minor anionic phospholipids present in the pulmonary surfactant complex, palmitoyl-oleoyl-phosphatidylglycerol (POPG) and phosphatidylinositol (PI), antagonize the cognate ligand activation of TLRs 2 and 4. The lipids block recognition of activating ligands by the TLRs, either directly or via the TLR4 coreceptors CD14 and MD2. Antagonism of TLR activation results in inhibition of the initiating step of the pro-inflammatory signaling pathways. Evidence for this mechanism of action comes from direct binding studies between CD14 and MD2 with POPG and PI. Additional evidence for this mechanism of antagonism also comes from monitoring the reduction of protein phosphorylation events that characterize the intracellular signaling by activated TLRs. The pathogenesis of respiratory syncytial virus (RSV) and influenza A virus (IAV) have been linked to TLR4 activation, and we examined the action of POPG and PI as potential antagonists of the pathology of these viruses. Surprisingly, POPG and PI dramatically curtail infection, in addition to inhibiting inflammatory sequelae associated with RSV and IAV infections. The mechanism of action by the lipids is disruption of virus particle binding to host cell plasma membrane receptors, required for viral uptake. The antagonism of activation of TLRs and virus binding to the alveolar epithelium by resident constituents of the pulmonary surfactant system suggests that POPG and PI function in homeostasis, to prevent inflammatory processes that result in reductions in gas exchange within the alveolar compartment.


Assuntos
Imunidade Inata/fisiologia , Vírus da Influenza A/isolamento & purificação , Fosfolipídeos/fisiologia , Vírus Sinciciais Respiratórios/isolamento & purificação , Infecções Respiratórias/imunologia , Infecções Respiratórias/virologia , Animais , Humanos , Fosfolipídeos/metabolismo , Surfactantes Pulmonares/metabolismo
20.
Am J Vet Res ; 80(3): 300-305, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30801214

RESUMO

OBJECTIVE To evaluate the lipidomic profile of surfactant obtained from horses with asthma at various clinical stages and to compare results with findings for healthy horses exposed to the same conditions. SAMPLE Surfactant samples obtained from 6 horses with severe asthma and 7 healthy horses. PROCEDURES Clinical evaluation of horses and surfactant analysis were performed. Samples obtained from horses with severe asthma and healthy horses before (baseline), during, and after exposure to hay were analyzed. Crude surfactant pellets were dried prior to dissolution in a solution of isopropanol:methanol:chloroform (4:2:1) containing 7.5mM ammonium acetate. Shotgun lipidomics were performed by use of high-resolution data acquisition on an ion-trap mass spectrometer. Findings were analyzed by use of an ANOVA with a Tukey-Kramer post hoc test. RESULTS Results of lipidomic analysis were evaluated to detect significant differences between groups of horses and among exposure statuses within groups of horses. Significantly increased amounts of cyclic phosphatidic acid (cPA) and diacylglycerol (DAG) were detected in surfactant from severely asthmatic horses during exposure to hay, compared with baseline and postexposure concentrations. Concentrations of cPA and DAG did not change significantly in healthy horses regardless of exposure status. CONCLUSIONS AND CLINICAL RELEVANCE cPA 16:0 and DAG 36:2 were 2 novel lipid mediators identified in surfactant obtained from asthmatic horses with clinical disease. These molecules were likely biomarkers of sustained inflammation. Further studies are needed to evaluate a possible correlation with disease severity and potential alterations in the plasma lipidomic profile of horses with asthma.


Assuntos
Asma/veterinária , Doenças dos Cavalos/metabolismo , Metabolismo dos Lipídeos , Surfactantes Pulmonares/metabolismo , Animais , Biomarcadores/metabolismo , Cavalos , Poaceae
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