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1.
Nat Commun ; 12(1): 1565, 2021 03 10.
Artigo em Inglês | MEDLINE | ID: mdl-33692365

RESUMO

During late lung development, alveolar and microvascular development is finalized to enable sufficient gas exchange. Impaired late lung development manifests as bronchopulmonary dysplasia (BPD) in preterm infants. Single-cell RNA sequencing (scRNA-seq) allows for assessment of complex cellular dynamics during biological processes, such as development. Here, we use MULTI-seq to generate scRNA-seq profiles of over 66,000 cells from 36 mice during normal or impaired lung development secondary to hyperoxia with validation of some of the findings in lungs from BPD patients. We observe dynamic populations of cells, including several rare cell types and putative progenitors. Hyperoxia exposure, which mimics the BPD phenotype, alters the composition of all cellular compartments, particularly alveolar epithelium, stromal fibroblasts, capillary endothelium and macrophage populations. Pathway analysis and predicted dynamic cellular crosstalk suggest inflammatory signaling as the main driver of hyperoxia-induced changes. Our data provides a single-cell view of cellular changes associated with late lung development in health and disease.


Assuntos
Hiperóxia/genética , Hiperóxia/fisiopatologia , Pulmão/metabolismo , Pulmão/patologia , Análise de Sequência de RNA/métodos , Análise de Célula Única/métodos , Animais , Displasia Broncopulmonar/genética , Displasia Broncopulmonar/patologia , Genótipo , Masculino , Camundongos
2.
PLoS One ; 15(9): e0239562, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32966330

RESUMO

Reproducible and unbiased methods to quantify alveolar structure are important for research on many lung diseases. However, manually estimating alveolar structure through stereology is time consuming and inter-observer variability is high. The objective of this work was to develop and validate a fast, reproducible and accurate (semi-)automatic alternative. A FIJI-macro was designed that automatically segments lung images to binary masks, and counts the number of test points falling on tissue and the number of intersections of the air-tissue interface with a set of test lines. Manual selection remains necessary for the recognition of non-parenchymal tissue and alveolar exudates. Volume density of alveolar septa ([Formula: see text]) and mean linear intercept of the airspaces (Lm) as measured by the macro were compared to theoretical values for 11 artificial test images and to manually counted values for 17 lungs slides using linear regression and Bland-Altman plots. Inter-observer agreement between 3 observers, measuring 8 lungs both manually and automatically, was assessed using intraclass correlation coefficients (ICC). [Formula: see text] and Lm measured by the macro closely approached theoretical values for artificial test images (R2 of 0.9750 and 0.9573 and bias of 0.34% and 8.7%). The macro data in lungs were slightly higher for [Formula: see text] and slightly lower for Lm in comparison to manually counted values (R2 of 0.8262 and 0.8288 and bias of -6.0% and 12.1%). Visually, semi-automatic segmentation was accurate. Most importantly, manually counted [Formula: see text] and Lm had only moderate to good inter-observer agreement (ICC 0.859 and 0.643), but agreements were excellent for semi-automatically counted values (ICC 0.956 and 0.900). This semi-automatic method provides accurate and highly reproducible alveolar morphometry results. Future efforts should focus on refining methods for automatic detection of non-parenchymal tissue or exudates, and for assessment of lung structure on 3D reconstructions of lungs scanned with microCT.


Assuntos
Displasia Broncopulmonar/patologia , Interpretação de Imagem Assistida por Computador/métodos , Alvéolos Pulmonares/patologia , Animais , Displasia Broncopulmonar/diagnóstico por imagem , Modelos Animais de Doenças , Feminino , Técnicas Histológicas/estatística & dados numéricos , Variações Dependentes do Observador , Gravidez , Alvéolos Pulmonares/diagnóstico por imagem , Coelhos , Interpretação de Imagem Radiográfica Assistida por Computador/métodos , Microtomografia por Raio-X/estatística & dados numéricos
3.
Am J Respir Crit Care Med ; 202(8): 1088-1104, 2020 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-32628504

RESUMO

Rationale: Promoting endogenous pulmonary regeneration is crucial after damage to restore normal lungs and prevent the onset of chronic adult lung diseases.Objectives: To investigate whether the cell-cycle inhibitor p16INK4a limits lung regeneration after newborn bronchopulmonary dysplasia (BPD), a condition characterized by the arrest of alveolar development, leading to adult sequelae.Methods: We exposed p16INK4a-/- and p16INK4a ATTAC (apoptosis through targeted activation of caspase 8) transgenic mice to postnatal hyperoxia, followed by pneumonectomy of the p16INK4a-/- mice. We measured p16INK4a in blood mononuclear cells of preterm newborns, 7- to 15-year-old survivors of BPD, and the lungs of patients with BPD.Measurements and Main Results: p16INK4a concentrations increased in lung fibroblasts after hyperoxia-induced BPD in mice and persisted into adulthood. p16INK4a deficiency did not protect against hyperoxic lesions in newborn pups but promoted restoration of the lung architecture by adulthood. Curative clearance of p16INK4a-positive cells once hyperoxic lung lesions were established restored normal lungs by adulthood. p16INK4a deficiency increased neutral lipid synthesis and promoted lipofibroblast and alveolar type 2 (AT2) cell development within the stem-cell niche. Besides, lipofibroblasts support self-renewal of AT2 cells into alveolospheres. Induction with a PPARγ (peroxisome proliferator-activated receptor γ) agonist after hyperoxia also increased lipofibroblast and AT2 cell numbers and restored alveolar architecture in hyperoxia-exposed mice. After pneumonectomy, p16INK4a deficiency again led to an increase in lipofibroblast and AT2 cell numbers in the contralateral lung. Finally, we observed p16INK4a mRNA overexpression in the blood and lungs of preterm newborns, which persisted in the blood of older survivors of BPD.Conclusions: These data demonstrate the potential of targeting p16INK4a and promoting lipofibroblast development to stimulate alveolar regeneration from childhood to adulthood.


Assuntos
Displasia Broncopulmonar/patologia , Inibidor p16 de Quinase Dependente de Ciclina/metabolismo , Fibroblastos/metabolismo , Pulmão/fisiologia , Regeneração/fisiologia , Adolescente , Adulto , Células Epiteliais Alveolares/metabolismo , Células Epiteliais Alveolares/patologia , Animais , Animais Recém-Nascidos , Apoptose , Displasia Broncopulmonar/metabolismo , Células Cultivadas , Criança , Modelos Animais de Doenças , Fibroblastos/patologia , Humanos , Hiperóxia/complicações , Hiperóxia/metabolismo , Hiperóxia/patologia , Recém-Nascido , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Alvéolos Pulmonares/patologia , Distribuição Aleatória , Amostragem , Adulto Jovem
4.
PLoS One ; 15(7): e0235901, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32673340

RESUMO

OBJECTIVE: To investigate the risk factors for BPD severity by gestational age (GA) and identify a way to reduce the incidence of moderate-to-severe BPD. STUDY DESIGN: This was a retrospective cohort study of very-low-birth-weight-infants (VLBWIs) delivered at 24 to 28 weeks GA from Korean Neonatal Network registry between 2013 and 2016. BPD was defined using the National Institutes of Health criteria. Study populations were divided by GA and subdivided into no/mild BPD and moderate/severe BPD. The initial statuses of all infants, including those who died before BPD diagnosis and the maternal and neonatal factors of the live infants were compared. Statistical methods included descriptive statistics, comparative tests, and logistic regression. RESULTS: Of 3,976 infants, 3,717 were included (24weeks, n = 456; 25 weeks, n = 650, 26 weeks, n = 742; 27 weeks, n = 836; 28 weeks, n = 1,033). The overall mortality rate was 18% and the rates by GA were 43%, 29%, 11%, and 6% in the 24-, 25-, 26-, 27-, 28-GA groups, respectively. Small for GA (SGA), treated patent ductus arteriosus (PDA), hypotension, and late-onset sepsis were significant risk factors for developing moderate/severe BPD in the 25 to 28-week GA groups in the multivariate analyses. However, for infants born at 24 weeks GA, there were no significant risk factors apart from initial resuscitation. CONCLUSIONS: Effective initial resuscitation was the most important factor for infants delivered at 24 weeks GA determining the severity of BPD. For infants delivered between 25 and 28 weeks, judicious care of SGA infants, aggressive treatment for PDA and hypotension, and intense efforts to decrease the sepsis rate are needed to reduce the development of moderate-to-severe BPD.


Assuntos
Displasia Broncopulmonar/patologia , Idade Gestacional , Displasia Broncopulmonar/epidemiologia , Displasia Broncopulmonar/etiologia , Displasia Broncopulmonar/mortalidade , Permeabilidade do Canal Arterial/complicações , Feminino , Humanos , Hipotensão/complicações , Incidência , Recém-Nascido , Recém-Nascido de muito Baixo Peso , Unidades de Terapia Intensiva Neonatal , Modelos Logísticos , Masculino , Sistema de Registros , República da Coreia , Ressuscitação/efeitos adversos , Estudos Retrospectivos , Fatores de Risco , Sepse/complicações , Índice de Gravidade de Doença , Taxa de Sobrevida
5.
Am J Respir Crit Care Med ; 202(8): 1146-1158, 2020 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-32551816

RESUMO

Rationale: Antenatal inflammation with placental dysfunction is strongly associated with high bronchopulmonary dysplasia (BPD) risk in preterm infants. Whether antenatal or postnatal HIF (hypoxia-inducible factor) augmentation can preserve lung structure and function and prevent pulmonary hypertension after intrauterine inflammation is controversial.Objectives: To determine whether antenatal or postnatal prolyl-hydroxylase inhibitor (PHi) therapy increases lung HIF expression, preserves lung growth and function, and prevents pulmonary hypertension in a rat model of chorioamnionitis-induced BPD caused by antenatal inflammation.Methods: Endotoxin (ETX) was administered to pregnant rats by intraamniotic injection at Embryonic Day 20, and pups were delivered by cesarean section at Embryonic Day 22. Selective PHi drugs, dimethyloxalylglycine or GSK360A, were administered into the amniotic space at Embryonic Day 20 or after birth by intraperitoneal injection for 2 weeks. Placentas and lung tissue were collected at birth for morphometric and Western blot measurements of HIF-1a, HIF-2a, VEGF (vascular endothelial growth factor), and eNOS (endothelial nitric oxide synthase) protein contents. At Day 14, lung function was assessed, and tissues were harvested to determine alveolarization by radial alveolar counts, pulmonary vessel density, and right ventricle hypertrophy (RVH).Measurements and Main Results: Antenatal PHi therapy preserves lung alveolar and vascular growth and lung function and prevents RVH after intrauterine ETX exposure. Antenatal administration of PHi markedly upregulates lung HIF-1a, HIF-2a, VEGF, and eNOS expression after ETX exposure.Conclusions: HIF augmentation improves lung structure and function, prevents RVH, and improves placental structure following antenatal ETX exposure. We speculate that antenatal or postnatal PHi therapy may provide novel strategies to prevent BPD due to antenatal inflammation.


Assuntos
Displasia Broncopulmonar/tratamento farmacológico , Fator 1 Induzível por Hipóxia/metabolismo , Pulmão/efeitos dos fármacos , Peptídeo PHI/farmacologia , Prenhez , Aminoácidos Dicarboxílicos/farmacologia , Animais , Animais Recém-Nascidos , Western Blotting , Displasia Broncopulmonar/metabolismo , Displasia Broncopulmonar/patologia , Modelos Animais de Doenças , Endotoxinas/efeitos adversos , Endotoxinas/farmacologia , Feminino , Fator 1 Induzível por Hipóxia/efeitos dos fármacos , Imuno-Histoquímica , Técnicas In Vitro , Injeções Intralesionais , Pulmão/embriologia , Gravidez , Cuidado Pré-Natal , Alvéolos Pulmonares/efeitos dos fármacos , Alvéolos Pulmonares/crescimento & desenvolvimento , Circulação Pulmonar/efeitos dos fármacos , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley , Valores de Referência , Testes de Função Respiratória , Técnicas de Cultura de Tecidos
6.
Am J Pathol ; 190(9): 1801-1812, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32526165

RESUMO

Bronchopulmonary dysplasia (BPD) and retinopathy of prematurity (ROP) are two debilitating disorders that develop in preterm infants exposed to supplemental oxygen to prevent respiratory failure. Both can lead to lifelong disabilities, such as chronic obstructive pulmonary disease and vision loss. Due to the lack of a standard experimental model of coincident disease, the underlying associations between BPD and ROP are not well characterized. To address this gap, we used the robust mouse model of oxygen-induced retinopathy exposing C57BL/6 mice to 75% oxygen from postnatal day 7 to 12. The cardinal features of ROP were replicated by this strategy, and the lungs of the same mice were simultaneously examined for evidence of BPD-like lung injury, investigating both the short- and long-term effects of early-life supplemental oxygen exposure. At postnatal days 12 and 18, mild lung disease was evident by histopathologic analysis together with the expected vasculopathy in the inner retina. At later time points, the lung lesion had progressed to severe airspace enlargement and alveolar simplification, with concurrent thinning in the outer layer of the retina. In addition, critical angiogenic oxidative stress and inflammatory factors reported to be dysregulated in ROP were similarly impaired in the lungs. These data shed new light on the interconnectedness of these two neonatal disorders, holding potential for the discovery of novel targets to treat BPD and ROP.


Assuntos
Displasia Broncopulmonar/etiologia , Modelos Animais de Doenças , Oxigenoterapia/efeitos adversos , Oxigênio/toxicidade , Retinopatia da Prematuridade/etiologia , Animais , Animais Recém-Nascidos , Displasia Broncopulmonar/patologia , Inflamação/etiologia , Inflamação/patologia , Camundongos , Camundongos Endogâmicos C57BL , Estresse Oxidativo/fisiologia , Retinopatia da Prematuridade/patologia
7.
Am J Pathol ; 190(8): 1763-1773, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32450152

RESUMO

Within the human lung, mast cells typically reside adjacent to the conducting airway and assume a mucosal phenotype (MCT). In rare pathologic conditions, connective tissue phenotype mast cells (MCTCs) can be found in the lung parenchyma. MCTCs accumulate in the lungs of infants with severe bronchopulmonary dysplasia, a chronic lung disease associated with preterm birth, which is characterized by pulmonary vascular dysmorphia. The human mast cell line (LUVA) was used to model MCTCs or MCTs. The ability of MCTCs to affect vascular organization during fetal lung development was tested in mouse lung explant cultures. The effect of MCTCs on in vitro tube formation and barrier function was studied using primary fetal human pulmonary microvascular endothelial cells. The mechanistic role of MCTC proteases was tested using inhibitors. MCTCLUVA but not MCTLUVA was associated with vascular dysmorphia in lung explants. In vitro, the addition of MCTCLUVA potentiated fetal human pulmonary microvascular endothelial cell interactions, inhibited tube stability, and disrupted endothelial cell junctions. Protease inhibitors ameliorated the ability of MCTCLUVA to alter endothelial cell angiogenic activities in vitro and ex vivo. These data indicate that MCTCs may directly contribute to disrupted angiogenesis in bronchopulmonary dysplasia. A better understanding of factors that regulate mast cell subtype and their different effector functions is essential.


Assuntos
Displasia Broncopulmonar/patologia , Células Endoteliais/patologia , Pulmão/patologia , Mastócitos/patologia , Neovascularização Fisiológica/fisiologia , Animais , Linhagem Celular , Células Cultivadas , Humanos , Camundongos
8.
Am J Respir Cell Mol Biol ; 63(3): 338-348, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32374619

RESUMO

Bronchopulmonary dysplasia (BPD) is a common and serious complication associated with preterm birth. The pathogenesis of BPD is incompletely understood, and there is an unmet clinical need for effective treatments. The role of autophagy as a potential cytoprotective mechanism in BPD remains to be fully elucidated. In the present study, we investigated the role and regulation of autophagy in experimental models of BPD. Regulation and cellular distribution of autophagic activity during postnatal lung development and in neonatal hyperoxia-induced lung injury (nHILI) were assessed in the autophagy reporter transgenic GFP-LC3 (GFP-microtubule-associated protein 1A/1B-light chain 3) mouse model. Autophagic activity and its regulation were also examined in a baboon model of BPD. The role of autophagy in nHILI was determined by assessing lung morphometry, injury, and inflammation in autophagy-deficient Beclin 1 heterozygous knockout mice (Becn1+/-). Autophagic activity was induced during alveolarization in control murine lungs and localized primarily to alveolar type II cells and macrophages. Hyperoxia exposure of neonatal murine lungs and BPD in baboon lungs resulted in impaired autophagic activity in association with insufficient AMPK (5'-AMP-activated protein kinase) and increased mTORC1 (mTOR complex 1) activation. Becn1+/- lungs displayed impaired alveolarization, increased alveolar septal thickness, greater neutrophil accumulation, and increased IL-1ß concentrations when exposed to nHILI. Becn1+/- alveolar macrophages isolated from nHILI-exposed mice displayed increased expression of proinflammatory genes. In conclusion, basal autophagy is induced during alveolarization and disrupted during progression of nHILI in mice and BPD in baboons. Becn1+/- mice are more susceptible to nHILI, suggesting that preservation of autophagic activity may be an effective protective strategy in BPD.


Assuntos
Autofagia/genética , Displasia Broncopulmonar/genética , Displasia Broncopulmonar/patologia , Hiperóxia/patologia , Células Epiteliais Alveolares/metabolismo , Animais , Autofagia/efeitos dos fármacos , Proteína Beclina-1/deficiência , Displasia Broncopulmonar/metabolismo , Modelos Animais de Doenças , Humanos , Hiperóxia/genética , Hiperóxia/metabolismo , Pulmão/patologia , Lesão Pulmonar/genética , Lesão Pulmonar/patologia , Macrófagos Alveolares/metabolismo , Camundongos Knockout , Pneumonia/patologia
9.
Am J Physiol Lung Cell Mol Physiol ; 318(4): L831-L843, 2020 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-32186397

RESUMO

PDGF-A is a key contributor to lung development in mice. Its expression is needed for secondary septation of the alveoli and deletion of the gene leads to abnormally enlarged alveolar air spaces in mice. In humans, the same phenotype is the hallmark of bronchopulmonary dysplasia (BPD), a disease that affects premature babies and may have long lasting consequences in adulthood. So far, the knowledge regarding adult effects of developmental arrest in the lung is limited. This is attributable to few follow-up studies of BPD survivors and lack of good experimental models that could help predict the outcomes of this early age disease for the adult individual. In this study, we used the constitutive lung-specific Pdgfa deletion mouse model to analyze the consequences of developmental lung defects in adult mice. We assessed lung morphology, physiology, cellular content, ECM composition and proteomics data in mature mice, that perinatally exhibited lungs with a BPD-like morphology. Histological and physiological analyses both revealed that enlarged alveolar air spaces remained until adulthood, resulting in higher lung compliance and higher respiratory volume in knockout mice. Still, no or only small differences were seen in cellular, ECM and protein content when comparing knockout and control mice. Taken together, our results indicate that Pdgfa deletion-induced lung developmental arrest has consequences for the adult lung at the morphological and functional level. In addition, these mice can reach adulthood with a BPD-like phenotype, which makes them a robust model to further investigate the pathophysiological progression of the disease and test putative regenerative therapies.


Assuntos
Pulmão/patologia , Fator de Crescimento Derivado de Plaquetas/genética , Animais , Displasia Broncopulmonar/genética , Displasia Broncopulmonar/patologia , Modelos Animais de Doenças , Feminino , Seguimentos , Hiperóxia/genética , Hiperóxia/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Alvéolos Pulmonares/patologia
10.
Eur J Pharmacol ; 873: 172983, 2020 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-32017936

RESUMO

Bronchopulmonary dysplasia (BPD), which remains a major clinical problem for preterm infants, is caused mainly by hyperoxia, mechanical ventilation and inflammation. Many approaches have been developed with the aim of decreasing the incidence of or alleviating BPD, but effective methods are still lacking. Gasotransmitters, a type of small gas molecule that can be generated endogenously, exert a protective effect against BPD-associated lung injury; nitric oxide (NO), carbon monoxide (CO) and hydrogen sulfide (H2S) are three such gasotransmitters. The protective effects of NO have been extensively studied in animal models of BPD, but the results of these studies are inconsistent with those of clinical trials. NO inhalation seems to have no effect on BPD, although side effects have been reported. NO inhalation is not recommended for BPD treatment in preterm infants, except those with severe pulmonary hypertension. Both CO and H2S decreased lung injury in BPD rodent models in preclinical studies. Another small gas molecule, hydrogen, exerts a protective effect against BPD. The nuclear factor erythroid-derived 2 (Nrf2)/heme oxygenase-1 (HO-1) axis seems to play a central role in the protective effect of these gasotransmitters on BPD. Gasotransmitters play important roles in mammals, but further clinical trials are needed to explore their effects on BPD.


Assuntos
Displasia Broncopulmonar/tratamento farmacológico , Monóxido de Carbono/uso terapêutico , Gasotransmissores/uso terapêutico , Sulfeto de Hidrogênio/uso terapêutico , Óxido Nítrico/uso terapêutico , Administração por Inalação , Animais , Displasia Broncopulmonar/patologia , Humanos , Hidrogênio/uso terapêutico , Recém-Nascido , Recém-Nascido Prematuro , Pulmão/patologia , Camundongos , Ratos
11.
Am J Surg Pathol ; 44(4): 509-515, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31934918

RESUMO

Bronchopulmonary dysplasia (BPD) is usually seen in premature infants who require mechanical ventilation and oxygen therapy for acute respiratory distress. Although most patients wean from oxygen therapy by the ages of 2 to 3, rehospitalization for respiratory problems is common in these patients in adulthood. There have been few studies that document the long-term outcomes of BPD survivors and information about the pulmonary function and radiographic findings of adult BPD are limited. Data on pathologic features of adult BPD are scarce. Three adult patients who underwent recent lung transplantation for BPD from 2 institutions were identified. Clinical data including clinical presentation, chest radiographic images, pulmonary function tests, cardiac catheterization, and echocardiography were retrieved from the electronic medical records. Hematoxylin and eosin and selective elastic stained sections of the explant lungs were examined. CD31 immunohistochemical stain is performed on representative sections. All 3 cases had similar clinical and radiologic features including the history of prematurity and long-term mechanical ventilation after birth, hyperexpanded lungs with air trapping and mosaic attenuation on chest computed tomographic scan, severe obstructive changes on pulmonary function test, and pulmonary hypertension. Pathologic examination showed common features including enlarged and simplified alveoli, peribronchial, subpleural, and interlobular septal fibrosis, narrowing/obliteration of the small airways by elastosis and muscular hypertrophy, thickening of venous walls by fibromuscular hyperplasia, and bronchitis/bronchiolitis. Cholesterol granulomas were seen in 2 cases. The common pathologic findings in the lungs explain the clinical and radiologic findings. Future studies are warranted to further characterize the clinical and pathologic features of adult BPD to develop optimal management strategies for these patients.


Assuntos
Displasia Broncopulmonar/patologia , Displasia Broncopulmonar/cirurgia , Transplante de Pulmão , Pulmão/patologia , Pulmão/cirurgia , Adulto , Fatores Etários , Biópsia , Displasia Broncopulmonar/diagnóstico por imagem , Displasia Broncopulmonar/fisiopatologia , Feminino , Humanos , Indiana , Pulmão/diagnóstico por imagem , Pulmão/fisiopatologia , Masculino , Michigan , Sobreviventes , Fatores de Tempo , Tomografia Computadorizada por Raios X , Resultado do Tratamento , Adulto Jovem
12.
Curr Opin Pediatr ; 32(2): 210-215, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31833951

RESUMO

PURPOSE OF REVIEW: Clinical trials of mesenchymal stem/stromal cell (MSC) therapy for bronchopulmonary dysplasia (BPD) are underway. A thorough understanding of the preclinical work that underpins these trials is critical for neonatal practitioners to properly evaluate them. RECENT FINDINGS: Significant progress has been made in understanding that MSCs have anti-inflammatory and proangiogenic effects, and that these can be mediated by the noncellular exosome fraction of MSCs. SUMMARY: In rodent hyperoxia models of BPD, MSCs have a proangiogenic effect mediated largely by vascular endothelial growth factor and shift the balance of endogenous lung cells from a proinflammatory to a prohealing phenotype. MSC-derived exosomes can recapitulate these effects.


Assuntos
Displasia Broncopulmonar/terapia , Transplante de Células-Tronco Mesenquimais/métodos , Células-Tronco Mesenquimais/imunologia , Fibrose Pulmonar/prevenção & controle , Displasia Broncopulmonar/metabolismo , Displasia Broncopulmonar/patologia , Displasia Broncopulmonar/fisiopatologia , Exossomos , Humanos , Recém-Nascido , Unidades de Terapia Intensiva Neonatal , Células-Tronco Mesenquimais/fisiologia , Fibrose Pulmonar/terapia , Resultado do Tratamento , Fator A de Crescimento do Endotélio Vascular
13.
Biochem Biophys Res Commun ; 522(1): 33-39, 2020 01 29.
Artigo em Inglês | MEDLINE | ID: mdl-31735330

RESUMO

The objective of this study was to assess the role of NETs in BPD of hyperoxia-induced rat model and the effect of heparin on alveolarization and vascular development in BPD. The neonatal rats exposed to 90% oxygen continuously for 7 days to mimic BPD, meanwhile, the rats were injected by different doses of histones to evaluate the impact on lung injury. The newborn rats exposed to hyperoxia were injected by different doses of heparin (250 U/kg, 500 U/kg) or anti-H4 antibody to evaluate the effect of heparin. Histones and hyperoxia impaired alveolarization with the increase of mean linear intercept (MLI) and the decrease of radial alveolar count (RAC), decreased lung angiogenesis with the decrease expression of VEGF, and increased the expression of NETs, histones and pro-inflammatory factor. However, low dose heparin (250U/kg) administration enhanced survival, improved alveolarization and vascular development in hyperoxia-induced BPD, as well as reduced expression of NETs, histones and pro-inflammatory factor. We concluded that heparin improves alveolarization and vascularization in BPD by inhibiting NETs.


Assuntos
Displasia Broncopulmonar/metabolismo , Armadilhas Extracelulares/metabolismo , Heparina/farmacologia , Hiperóxia/metabolismo , Alvéolos Pulmonares/metabolismo , Animais , Animais Recém-Nascidos , Displasia Broncopulmonar/patologia , Feminino , Histonas/metabolismo , Inflamação , Pulmão/patologia , Neovascularização Fisiológica , Oxigênio/metabolismo , Ratos , Ratos Sprague-Dawley , Fator A de Crescimento do Endotélio Vascular/metabolismo
14.
Respir Res ; 20(1): 255, 2019 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-31718614

RESUMO

BACKGROUND: Bronchopulmonary dysplasia (BPD) is characterized by alveolar simplification and disordered angiogenesis. Stromal derived factor-1 (SDF-1) is a chemokine which modulates cell migration, proliferation, and angiogenesis. Here we tested the hypothesis that intra-tracheal (IT) administration of a naked plasmid DNA expressing SDF-1 would attenuate neonatal hyperoxia-induced lung injury in an experimental model of BPD, by promoting angiogenesis. DESIGN/METHODS: Newborn Sprague-Dawley rat pups (n = 18-20/group) exposed to room air (RA) or hyperoxia (85% O2) from postnatal day (P) 1 to 14 were randomly assigned to receive IT a naked plasmid expressing SDF-1, JVS-100 (Juventas Therapeutics, Cleveland, Ohio) or placebo (PL) on P3. Lung alveolarization, angiogenesis, inflammation, vascular remodeling and pulmonary hypertension (PH) were assessed on P14. PH was determined by measuring right ventricular systolic pressure (RVSP) and the weight ratio of the right to left ventricle + septum (RV/LV + S). Capillary tube formation in SDF-1 treated hyperoxia-exposed human pulmonary microvascular endothelial cells (HPMEC) was determined by matrigel assay. Data is expressed as mean ± SD and analyzed by two-way ANOVA. RESULTS: Exposure of neonatal pups to 14 days of hyperoxia decreased lung SDF-1 gene expression. Moreover, whilst hyperoxia exposure inhibited capillary tube formation in HPMEC, SDF-1 treatment increased tube length and branching in HPMEC. PL-treated hyperoxia-exposed pups had decreased alveolarization and lung vascular density. This was accompanied by an increase in RVSP, RV/LV + S, pulmonary vascular remodeling and inflammation. In contrast, IT JVS-100 improved lung structure, reduced inflammation, PH and vascular remodeling. CONCLUSIONS: Intratracheal administration of a naked plasmid expressing SDF-1 improves alveolar and vascular structure in an experimental model of BPD. These findings suggest that therapies which modulate lung SDF-1 expression may have beneficial effects in preterm infants with BPD.


Assuntos
Displasia Broncopulmonar/tratamento farmacológico , Quimiocina CXCL12/administração & dosagem , Pulmão/efeitos dos fármacos , Plasmídeos/administração & dosagem , Traqueia/efeitos dos fármacos , Animais , Animais Recém-Nascidos , Displasia Broncopulmonar/patologia , Displasia Broncopulmonar/fisiopatologia , Sistemas de Liberação de Medicamentos/métodos , Feminino , Expressão Gênica , Pulmão/anatomia & histologia , Pulmão/fisiologia , Plasmídeos/biossíntese , Plasmídeos/genética , Gravidez , Ratos , Ratos Sprague-Dawley , Roedores , Traqueia/fisiologia
15.
J Immunol ; 203(7): 1952-1960, 2019 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-31471525

RESUMO

IL-33, an IL-1 family cytokine, is constitutively expressed in mucosal tissues and other organs in healthy humans and animals, and expression levels increase in inflammatory conditions. Although IL-33-mediated promotion of type 2 immune responses has been well established, a gap in our knowledge regarding the functional diversity of this pleiotropic cytokine remains. To address this gap, we developed a new IL-33 transgenic mouse model in which overexpression of full-length IL-33 is induced in lung epithelial cells under conditional control. In adult mice, an ∼3-fold increase in the steady-state IL-33 levels produced no pathologic effects in the lungs. When exposed to airborne allergens, adult transgenic mice released more IL-33 extracellularly and exhibited robust type 2 immune responses. In neonatal transgenic mice, up to postnatal day 14, a similar increase in steady-state IL-33 levels resulted in increased mortality, enlarged alveolar spaces resembling bronchopulmonary dysplasia, and altered expression of genes associated with tissue morphogenesis. Processed 25-kDa IL-33 protein was detected in bronchoalveolar lavage fluids without any exogenous stimuli, and pathologic changes were abolished in mice deficient in the IL-33 receptor ST2. These findings suggest that adult lungs are relatively resistant to IL-33 overexpression unless they encounter environmental insults, whereas developing lungs are highly susceptible, with IL-33 overexpression resulting in detrimental and pathologic outcomes.


Assuntos
Alérgenos/imunologia , Displasia Broncopulmonar/imunologia , Exposição Ambiental/efeitos adversos , Proteína 1 Semelhante a Receptor de Interleucina-1/imunologia , Interleucina-33/imunologia , Alvéolos Pulmonares/imunologia , Animais , Animais Recém-Nascidos , Displasia Broncopulmonar/patologia , Células Epiteliais/imunologia , Células Epiteliais/patologia , Proteína 1 Semelhante a Receptor de Interleucina-1/genética , Interleucina-33/genética , Camundongos , Camundongos Knockout , Alvéolos Pulmonares/patologia
16.
Arch. bronconeumol. (Ed. impr.) ; 55(9): 465-471, sept. 2019. tab, graf
Artigo em Inglês | IBECS | ID: ibc-186156

RESUMO

Introduction: Endocan levels were found to be associated with severity and mortality of the respiratory system diseases. Objective: We aimed to figure out whether endocan was an important marker for the diagnosis, severity and follow-up of bronchopulmonary dysplasia (BPD). Materials and methods: Infants with moderate/severe BPD, and who required hydrocortisone treatment were included in the study group. Infants without BPD were allocated in the control group. Endocan levels were compared between the control group and the study group, and before and after the treatment in the study group. Results: A total of 148 infants, 74 infants in the control group and 74 infants in the BPD group, were included. The endocan level was higher in the BPD group than in the control group (P = .001). Endocan levels before treatment in the BPD group was found to be higher than endocan level after treatment (P = .021). Conclusion: Our study found that endocan levels increased in moderate/severe BPD. Serum endocan levels may be a safe and novel indicator for the follow-up of response to treatment and the prognosis of the severity of the disease


Introducción: Los niveles de endocan se han asociado con la mortalidad y la gravedad de enfermedades del aparato respiratorio. Objetivo: El objetivo fue averiguar si el endocan es un marcador útil para el diagnóstico, la gravedad y el seguimiento de la displasia broncopulmonar (DBP). Materiales y métodos: Se incluyeron en el estudio lactantes con DBP moderada/grave que requirieron tratamiento con hidrocortisona (grupo DBP). El grupo control lo constituyeron lactantes sin DBP. Los niveles de endocan se compararon entre el grupo control y el grupo de estudio y, en este último, tanto antes como después del tratamiento. Resultados: Se incluyeron un total de 148 lactantes; 74 en el grupo control y 74 en el grupo DBP. Los niveles de endocan fueron más elevados en el grupo DBP que en el grupo control (p = 0,001). Los niveles de endocan también resultaron superiores en el grupo DBP antes del tratamiento que después del mismo (p = 0,021). Conclusión: Nuestro estudio halló que los niveles de endocan se encuentran incrementados en la DBP moderada/grave. Los niveles séricos de endocan podrían utilizarse como un nuevo indicador seguro para el seguimiento de la respuesta al tratamiento y el pronóstico de gravedad de la enfermedad


Assuntos
Humanos , Lactente , Pulmão/patologia , Displasia Broncopulmonar/sangue , Recém-Nascido de muito Baixo Peso/sangue , Prognóstico , Proteoglicanas/análise , Pulmão/fisiopatologia , Biomarcadores/sangue , Displasia Broncopulmonar/diagnóstico , Displasia Broncopulmonar/patologia , Índice de Gravidade de Doença , Hidrocortisona/uso terapêutico
17.
Eur J Pharmacol ; 860: 172588, 2019 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-31377154

RESUMO

Bronchopulmonary dysplasia (BPD) is a chronic lung disease that often occurs in preterm infants. However, there is still no effective treatment for BPD. Recent studies demonstrated that connective tissue growth factor (CTGF) is involved in the development of BPD in experimental models. CTGF, also known as CCN2, is the second member of the CCN family and is necessary for normal lung development. The expression of CTGF is increased in lung tissues in infants with BPD. Hyperoxia, inflammation and mechanic ventilation increase CTGF expression which may promote fibroblast proliferation, matrix production and vascular remodeling. Conditional overexpression of CTGF in alveolar epithelial type II cells disrupts alveolarization and vascular development, induces vascular remodeling, and results in pulmonary hypertension, the pathological hallmarks of severe BPD. Further studies have shown that inhibition of CTGF by a CTGF monoclonal antibody improved alveolarization and vascular development, and decreased pulmonary vascular remodeling and pulmonary hypertension in a rodent model of BPD induced by hyperoxia. CTGF may be a novel target for BPD therapy in preterm infants.


Assuntos
Displasia Broncopulmonar/tratamento farmacológico , Fator de Crescimento do Tecido Conjuntivo/metabolismo , Terapia de Alvo Molecular/métodos , Animais , Displasia Broncopulmonar/metabolismo , Displasia Broncopulmonar/patologia , Humanos
18.
Cardiol Young ; 29(7): 945-953, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31287038

RESUMO

INTRODUCTION: Prematurity impacts myocardial development and may determine long-term outcomes. The objective of this study was to test the hypothesis that preterm neonates develop right ventricle dysfunction and adaptive remodelling by 32 weeks post-menstrual age that persists through 1 year corrected age. MATERIALS AND METHODS: A subset of 80 preterm infants (born <29 weeks) was selected retrospectively from a prospectively enrolled cohort and measures of right ventricle systolic function and morphology by two-dimensional echocardiography were assessed at 32 weeks post-menstrual age and at 1 year of corrected age. Comparisons were made to 50 term infants at 1 month and 1 year of age. Sub-analyses were performed in preterm-born infants with bronchopulmonary dysplasia and/or pulmonary hypertension. RESULT: In both term and preterm infants, right ventricle function and morphology increased over the first year (p < 0.01). The magnitudes of right ventricle function measures were lower in preterm-born infants at each time period (p < 0.01 for all) and right ventricle morphology indices were wider in all preterm infants by 1 year corrected age, irrespective of lung disease. Measures of a) right ventricle function were further decreased and b) morphology increased through 1 year in preterm infants with bronchopulmonary dysplasia and/or pulmonary hypertension (p < 0.01). CONCLUSION: Preterm infants exhibit abnormal right ventricle performance with remodelling at 32 weeks post-menstrual age that persists through 1 year corrected age, suggesting a less developed intrinsic myocardial function response following preterm birth. The development of bronchopulmonary dysplasia and pulmonary hypertension leave a further negative impact on right ventricle mechanics over the first year of age.


Assuntos
Displasia Broncopulmonar/complicações , Hipertensão Pulmonar/complicações , Doenças do Prematuro/patologia , Disfunção Ventricular Direita/etiologia , Disfunção Ventricular Direita/patologia , Remodelação Ventricular , Displasia Broncopulmonar/patologia , Ecocardiografia , Feminino , Humanos , Hipertensão Pulmonar/patologia , Lactente , Recém-Nascido , Recém-Nascido Prematuro , Doenças do Prematuro/diagnóstico por imagem , Doenças do Prematuro/etiologia , Masculino , Estudos Retrospectivos , Disfunção Ventricular Direita/diagnóstico por imagem
19.
Development ; 146(15)2019 08 09.
Artigo em Inglês | MEDLINE | ID: mdl-31331942

RESUMO

Postnatal alveolar formation is the most important and the least understood phase of lung development. Alveolar pathologies are prominent in neonatal and adult lung diseases. The mechanisms of alveologenesis remain largely unknown. We inactivated Pdgfra postnatally in secondary crest myofibroblasts (SCMF), a subpopulation of lung mesenchymal cells. Lack of Pdgfra arrested alveologenesis akin to bronchopulmonary dysplasia (BPD), a neonatal chronic lung disease. The transcriptome of mutant SCMF revealed 1808 altered genes encoding transcription factors, signaling and extracellular matrix molecules. Elastin mRNA was reduced, and its distribution was abnormal. Absence of Pdgfra disrupted expression of elastogenic genes, including members of the Lox, Fbn and Fbln families. Expression of EGF family members increased when Tgfb1 was repressed in mouse. Similar, but not identical, results were found in human BPD lung samples. In vitro, blocking PDGF signaling decreased elastogenic gene expression associated with increased Egf and decreased Tgfb family mRNAs. The effect was reversible by inhibiting EGF or activating TGFß signaling. These observations demonstrate the previously unappreciated postnatal role of PDGFA/PDGFRα in controlling elastogenic gene expression via a secondary tier of signaling networks composed of EGF and TGFß.


Assuntos
Família de Proteínas EGF/metabolismo , Miofibroblastos/metabolismo , Alvéolos Pulmonares/embriologia , Receptor alfa de Fator de Crescimento Derivado de Plaquetas/metabolismo , Fator de Crescimento Transformador beta1/metabolismo , Animais , Displasia Broncopulmonar/patologia , Proteínas de Ligação ao Cálcio/biossíntese , Diferenciação Celular/fisiologia , Células Cultivadas , Elastina/genética , Proteínas da Matriz Extracelular/biossíntese , Fibrilina-1/biossíntese , Humanos , Camundongos , Camundongos Knockout , Proteína-Lisina 6-Oxidase/biossíntese , RNA Mensageiro/genética , Fator de Crescimento Transformador beta1/biossíntese
20.
Front Immunol ; 10: 1480, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31354700

RESUMO

Pulmonary hypertension secondary to bronchopulmonary dysplasia (BPD-PH) represents a major complication of BPD in extremely preterm infants for which there are currently no safe and effective interventions. The abundance of interleukin-1 (IL-1) is strongly correlated with the severity and long-term outcome of BPD infants and we have previously shown that IL-1 receptor antagonist (IL-1Ra) protects against murine BPD; therefore, we hypothesized that IL-1Ra may also be effective against BPD-PH. We employed daily injections of IL-1Ra in a murine model in which BPD/BPD-PH was induced by antenatal LPS and postnatal hyperoxia of 65% O2. Pups reared in hyperoxia for 28 days exhibited a BPD-PH-like disease accompanied by significant changes in pulmonary vascular morphology: micro-CT revealed an 84% reduction in small vessels (4-5 µm diameter) compared to room air controls; this change was prevented by IL-1Ra. Pulmonary vascular resistance, assessed at day 28 of life by echocardiography using the inversely-related surrogate marker time-to-peak-velocity/right ventricular ejection time (TPV/RVET), increased in hyperoxic mice (0.27 compared to 0.32 in air controls), and fell significantly with daily IL-1Ra treatment (0.31). Importantly, in vivo cine-angiography revealed that this protection afforded by IL-1Ra treatment for 28 days is maintained at day 60 of life. Despite an increased abundance of mediators of pulmonary angiogenesis in day 5 lung lysates, namely vascular endothelial growth factor (VEGF) and endothelin-1 (ET-1), no difference was detected in ex vivo pulmonary vascular reactivity between air and hyperoxia mice as measured in precision cut lung slices, or by immunohistochemistry in alpha-smooth muscle actin (α-SMA) and endothelin receptor type-A (ETA) at day 28. Further, on day 28 of life we observed cardiac fibrosis by Sirius Red staining, which was accompanied by an increase in mRNA expression of galectin-3 and CCL2 (chemokine (C-C motif) ligand 2) in whole hearts of hyperoxic pups, which improved with IL-1Ra. In summary, our findings suggest that daily administration of the anti-inflammatory IL-1Ra prevents the increase in pulmonary vascular resistance and the pulmonary dysangiogenesis of murine BPD-PH, thus pointing to IL-1Ra as a promising candidate for the treatment of both BPD and BPD-PH.


Assuntos
Anti-Inflamatórios/farmacologia , Displasia Broncopulmonar/prevenção & controle , Hipertensão Pulmonar/prevenção & controle , Proteína Antagonista do Receptor de Interleucina 1/farmacologia , Resistência Vascular/efeitos dos fármacos , Animais , Animais Recém-Nascidos , Displasia Broncopulmonar/patologia , Modelos Animais de Doenças , Endotelina-1/metabolismo , Hiperóxia , Lipopolissacarídeos/toxicidade , Camundongos , Camundongos Endogâmicos C57BL , Fator A de Crescimento do Endotélio Vascular/metabolismo
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