RESUMO
Impaired pulmonary angiogenesis plays a pivotal role in the progression of pulmonary arterial hypertension (PAH) and patient mortality, yet the molecular mechanisms driving this process remain enigmatic. Our study uncovered a striking connection between mitochondrial dysfunction (MD), caused by a humanized mutation in the NFU1 gene, and severely disrupted pulmonary angiogenesis in adult lungs. Restoring the bioavailability of the NFU1 downstream target, lipoic acid (LA), alleviated MD and angiogenic deficiency and rescued the progressive PAH phenotype in the NFU1G206C model. Notably, significant NFU1 expression and signaling insufficiencies were also identified in idiopathic PAH (iPAH) patients' lungs, emphasizing this study's relevance beyond NFU1 mutation cases. The remarkable improvement in mitochondrial function of PAH patient-derived pulmonary artery endothelial cells (PAECs) following LA supplementation introduces LA as a potential therapeutic approach. In conclusion, this study unveils a novel role for MD in dysregulated pulmonary angiogenesis and PAH manifestation, emphasizing the need to correct MD in PAH patients with unrecognized NFU1/LA deficiency.
Assuntos
Mitocôndrias , Ácido Tióctico , Humanos , Mitocôndrias/metabolismo , Mitocôndrias/patologia , Animais , Ácido Tióctico/farmacologia , Células Endoteliais/metabolismo , Células Endoteliais/patologia , Hipertensão Arterial Pulmonar/metabolismo , Hipertensão Arterial Pulmonar/genética , Hipertensão Arterial Pulmonar/patologia , Neovascularização Patológica/metabolismo , Camundongos , Masculino , Artéria Pulmonar/patologia , Artéria Pulmonar/metabolismo , Pulmão/irrigação sanguínea , Pulmão/metabolismo , Pulmão/patologia , Mutação , Feminino , Hipertensão Pulmonar Primária Familiar/metabolismo , Hipertensão Pulmonar Primária Familiar/genética , Hipertensão Pulmonar Primária Familiar/patologia , Camundongos Endogâmicos C57BL , Transdução de Sinais , Hipertensão Pulmonar/metabolismo , Hipertensão Pulmonar/patologia , Hipertensão Pulmonar/genéticaRESUMO
Evidences illustrate that cell senescence contributes to the development of pulmonary arterial hypertension. However, the molecular mechanisms remain unclear. Since there may be different senescence subtypes between PAH patients, consistent senescence-related genes (SRGs) were utilized for consistent clustering by unsupervised clustering methods. Senescence is inextricably linked to the immune system, and the immune cells in each cluster were estimated by ssGSEA. To further screen out more important SRGs, machine learning algorithms were used for identification and their diagnostic value was assessed by ROC curves. The expression of hub genes were verified in vivo and in vitro. Transcriptome analysis was used to assess the effects of silence of hub gene on different pathways. Three senescence molecular subtypes were identified by consensus clustering. Compared with cluster A and B, most immune cells and checkpoint genes were higher in cluster C. Thus, we identified senescence cluster C as the immune subtype. The ROC curves of IGF1, HOXB7, and YWHAZ were remarkable in both datasets. The expression of these genes was increased in vitro. Western blot and immunohistochemical analyses revealed that YWHAZ expression was also increased. Our transcriptome analysis showed autophagy-related genes were significantly elevated after silence of YWHAZ. Our research provided several prospective SRGs and molecular subtypes. Silence of YWHAZ may contribute to the clearance of senescent endothelial cells by activating autophagy.
Assuntos
Senescência Celular , Hipertensão Pulmonar Primária Familiar , Perfilação da Expressão Gênica , Humanos , Senescência Celular/genética , Hipertensão Pulmonar Primária Familiar/genética , Hipertensão Pulmonar Primária Familiar/metabolismo , Hipertensão Pulmonar Primária Familiar/patologia , Transcriptoma , Feminino , Masculino , Autofagia/genética , Aprendizado de Máquina , Proteínas 14-3-3/genética , Proteínas 14-3-3/metabolismo , Análise por ConglomeradosRESUMO
BACKGROUND: STIM1 (stromal interaction molecule 1) regulates store-operated calcium entry and is involved in pulmonary artery vasoconstriction and pulmonary artery smooth muscle cell proliferation, leading to pulmonary arterial hypertension (PAH). METHODS: Bioinformatics analysis and a 2-stage matched case-control study were conducted to screen for noncoding variants that may potentially affect STIM1 transcriptional regulation in 242 patients with idiopathic PAH and 414 healthy controls. Luciferase reporter assay, real-time quantitative polymerase chain reaction, western blot, 5-ethynyl-2'-deoxyuridine (EdU) assay, and intracellular Ca2+ measurement were performed to study the mechanistic roles of those STIM1 noncoding variants in PAH. RESULTS: Five noncoding variants (rs3794050, rs7934581, rs3750996, rs1561876, and rs3750994) were identified and genotyped using Sanger sequencing. Rs3794050, rs7934581, and rs1561876 were associated with idiopathic PAH (recessive model, all P<0.05). Bioinformatics analysis showed that these 3 noncoding variants possibly affect the enhancer function of STIM1 or the microRNA (miRNA) binding to STIM1. Functional validation performed in HEK293 and pulmonary artery smooth muscle cells demonstrated that the noncoding variant rs1561876-G (STIM1 mutant) had significantly stronger transcriptional activity than the wild-type counterpart, rs1561876-A, by affecting the transcriptional regulatory function of both hsa-miRNA-3140-5p and hsa-miRNA-4766-5p. rs1561876-G enhanced intracellular Ca2+ signaling in human pulmonary artery smooth muscle cells secondary to calcium-sensing receptor activation and promoted proliferation of pulmonary artery smooth muscle cells under both normoxia and hypoxia conditions, suggesting a possible contribution to PAH development. CONCLUSIONS: The potential clinical implications of the 3 noncoding variants of STIM1, rs3794050, rs7934581, and rs1561876, are 2-fold, as they may help predict the risk and prognosis of idiopathic PAH and guide investigations on novel therapeutic pathway(s).
Assuntos
Artéria Pulmonar , Molécula 1 de Interação Estromal , Humanos , Molécula 1 de Interação Estromal/genética , Molécula 1 de Interação Estromal/metabolismo , Masculino , Feminino , Estudos de Casos e Controles , Pessoa de Meia-Idade , Adulto , Proteínas de Neoplasias/genética , Miócitos de Músculo Liso/metabolismo , Hipertensão Pulmonar Primária Familiar/genética , Hipertensão Pulmonar Primária Familiar/fisiopatologia , Predisposição Genética para Doença , Músculo Liso Vascular/metabolismo , Regulação da Expressão Gênica , Proliferação de Células/genética , Polimorfismo de Nucleotídeo ÚnicoRESUMO
BACKGROUND: Pulmonary hypertension (PH) is a common complication of systemic sclerosis (SSc) and a leading cause of mortality among patients with this disease. PH can also occur as an idiopathic condition (idiopathic pulmonary arterial hypertension). Investigation of transcriptomic alterations in vascular populations is critical to elucidating cellular mechanisms underlying pathobiology of SSc-associated and idiopathic PH. METHODS: We analyzed single-cell RNA sequencing profiles of endothelial and perivascular mesenchymal populations from explanted lung tissue of patients with SSc-associated PH (n=16), idiopathic pulmonary arterial hypertension (n=3), and healthy controls (n=15). Findings were validated by immunofluorescence staining of explanted human lung tissue. RESULTS: Three disease-associated endothelial populations emerged. Two angiogenic endothelial cell (EC) subtypes markedly expanded in SSc-associated PH lungs: tip ECs expressing canonical tip markers PGF and APLN and phalanx ECs expressing genes associated with vascular development, endothelial barrier integrity, and Notch signaling. Gene regulatory network analysis suggested enrichment of Smad1 (SMAD family member 1) and PPAR-γ (peroxisome proliferator-activated receptor-γ) regulon activities in these 2 populations, respectively. Mapping of potential ligand-receptor interactions highlighted Notch, apelin-APJ (apelin receptor), and angiopoietin-Tie (tyrosine kinase with immunoglobulin-like and EGF-like domains 1) signaling pathways between angiogenic ECs and perivascular cells. Transitional cells, expressing both endothelial and pericyte/smooth muscle cell markers, provided evidence for the presence of endothelial-to-mesenchymal transition. Transcriptional programs associated with arterial endothelial dysfunction implicated VEGF-A (vascular endothelial growth factor-A), TGF-ß1 (transforming growth factor beta-1), angiotensin, and TNFSF12 (tumor necrosis factor ligand superfamily member 12)/TWEAK (TNF-related weak inducer of apoptosis) in the injury/remodeling phenotype of PH arterial ECs. CONCLUSIONS: These data provide high-resolution insights into the complexity and plasticity of the pulmonary endothelium in SSc-associated PH and idiopathic pulmonary arterial hypertension and provide direct molecular insights into soluble mediators and transcription factors driving PH vasculopathy.
Assuntos
Neovascularização Patológica , Escleroderma Sistêmico , Remodelação Vascular , Humanos , Escleroderma Sistêmico/genética , Escleroderma Sistêmico/patologia , Escleroderma Sistêmico/metabolismo , Escleroderma Sistêmico/complicações , Masculino , Feminino , Pessoa de Meia-Idade , Hipertensão Pulmonar Primária Familiar/metabolismo , Hipertensão Pulmonar Primária Familiar/genética , Hipertensão Pulmonar Primária Familiar/fisiopatologia , Hipertensão Pulmonar Primária Familiar/patologia , Estudos de Casos e Controles , Células Endoteliais/metabolismo , Células Endoteliais/patologia , Artéria Pulmonar/metabolismo , Artéria Pulmonar/patologia , Artéria Pulmonar/fisiopatologia , Transcriptoma , Transdução de Sinais , Adulto , Análise de Célula Única , Pulmão/metabolismo , Pulmão/irrigação sanguínea , Pulmão/patologia , Redes Reguladoras de Genes , AngiogêneseRESUMO
BACKGROUND: Inflammation and dysregulated immunity play vital roles in idiopathic pulmonary arterial hypertension (IPAH), while the mechanisms that initiate and promote these processes are unclear. METHODS: Transcriptomic data of lung tissues from IPAH patients and controls were obtained from the Gene Expression Omnibus database. Weighted gene co-expression network analysis (WGCNA), differential expression analysis, protein-protein interaction (PPI) and functional enrichment analysis were combined with a hemodynamically-related histopathological score to identify inflammation-associated hub genes in IPAH. The monocrotaline-induced rat model of pulmonary hypertension was utilized to confirm the expression pattern of these hub genes. Single-cell RNA-sequencing (scRNA-seq) data were used to identify the hub gene-expressing cell types and their intercellular interactions. RESULTS: Through an extensive bioinformatics analysis, CXCL9, CCL5, GZMA and GZMK were identified as hub genes that distinguished IPAH patients from controls. Among these genes, pulmonary expression levels of Cxcl9, Ccl5 and Gzma were elevated in monocrotaline-exposed rats. Further investigation revealed that only CCL5 and GZMA were highly expressed in T and NK cells, where CCL5 mediated T and NK cell interaction with endothelial cells, smooth muscle cells, and fibroblasts through multiple receptors. CONCLUSIONS: Our study identified a new inflammatory pathway in IPAH, where T and NK cells drove heightened inflammation predominantly via the upregulation of CCL5, providing groundwork for the development of targeted therapeutics.
Assuntos
Quimiocina CCL5 , Hipertensão Pulmonar Primária Familiar , Células Matadoras Naturais , RNA-Seq , Análise de Célula Única , Linfócitos T , Animais , Humanos , Quimiocina CCL5/metabolismo , Quimiocina CCL5/genética , Células Matadoras Naturais/metabolismo , Células Matadoras Naturais/imunologia , Hipertensão Pulmonar Primária Familiar/genética , Hipertensão Pulmonar Primária Familiar/patologia , Hipertensão Pulmonar Primária Familiar/metabolismo , Linfócitos T/metabolismo , Linfócitos T/imunologia , Masculino , Comunicação Celular/genética , Ratos Sprague-Dawley , Pulmão/patologia , Ratos , Redes Reguladoras de Genes , Monocrotalina , Mapas de Interação de Proteínas/genética , Biologia ComputacionalRESUMO
Heritable pulmonary arterial hypertension (PAH) can be triggered by at least 18 genes. The most frequently altered gene is the bone morphogenetic protein receptor 2 (BMPR2). Further genes from the same pathway are also well known PAH-causing genes. Genetic testing can aid to confirm differential diagnoses such as a pulmonary veno-occlusive disease. It also enables the testing of healthy family members. In addition to the PAH patient population particularly served by genetic testing, this article touches on the mode of inheritance and provides insights into the first treatments soon on the market that rebalance the BMPR2 signaling pathway.
Assuntos
Receptores de Proteínas Morfogenéticas Ósseas Tipo II , Humanos , Receptores de Proteínas Morfogenéticas Ósseas Tipo II/genética , Receptores de Proteínas Morfogenéticas Ósseas Tipo II/metabolismo , Testes Genéticos , Hipertensão Arterial Pulmonar/genética , Hipertensão Arterial Pulmonar/diagnóstico , Hipertensão Arterial Pulmonar/fisiopatologia , Hipertensão Pulmonar/genética , Hipertensão Pulmonar/diagnóstico , Hipertensão Pulmonar/terapia , Hipertensão Pulmonar Primária Familiar/genética , Hipertensão Pulmonar Primária Familiar/diagnóstico , Hipertensão Pulmonar Primária Familiar/fisiopatologia , Predisposição Genética para Doença , Transdução de SinaisRESUMO
Pulmonary hypertension (PH) is a progressive, severe and to date not curable disease of the pulmonary vasculature. Alterations of the insulin-like growth factor 1 (IGF-1) system are known to play a role in vascular pathologies and IGF-binding proteins (IGFBPs) are important regulators of the bioavailability and function of IGFs. In this study, we show that circulating plasma levels of IGFBP-1, IGFBP-2 and IGFBP-3 are increased in idiopathic pulmonary arterial hypertension (IPAH) patients compared to healthy individuals. These binding proteins inhibit the IGF-1 induced IGF-1 receptor (IGF1R) phosphorylation and exhibit diverging effects on the IGF-1 induced signaling pathways in human pulmonary arterial cells (i.e. healthy as well as IPAH-hPASMCs, and healthy hPAECs). Furthermore, IGFBPs are differentially expressed in an experimental mouse model of PH. In hypoxic mouse lungs, IGFBP-1 mRNA expression is decreased whereas the mRNA for IGFBP-2 is increased. In contrast to IGFBP-1, IGFBP-2 shows vaso-constrictive properties in the murine pulmonary vasculature. Our analyses show that IGFBP-1 and IGFBP-2 exhibit diverging effects on IGF-1 signaling and display a unique IGF1R-independent kinase activation pattern in human pulmonary arterial smooth muscle cells (hPASMCs), which represent a major contributor of PAH pathobiology. Furthermore, we could show that IGFBP-2, in contrast to IGFBP-1, induces epidermal growth factor receptor (EGFR) signaling, Stat-3 activation and expression of Stat-3 target genes. Based on our results, we conclude that the IGFBP family, especially IGFBP-1, IGFBP-2 and IGFBP-3, are deregulated in PAH, that they affect IGF signaling and thereby regulate the cellular phenotype in PH.
Assuntos
Modelos Animais de Doenças , Proteína 1 de Ligação a Fator de Crescimento Semelhante à Insulina , Proteína 2 de Ligação a Fator de Crescimento Semelhante à Insulina , Proteína 3 de Ligação a Fator de Crescimento Semelhante à Insulina , Fator de Crescimento Insulin-Like I , Miócitos de Músculo Liso , Artéria Pulmonar , Receptor IGF Tipo 1 , Transdução de Sinais , Humanos , Animais , Receptor IGF Tipo 1/metabolismo , Receptor IGF Tipo 1/genética , Artéria Pulmonar/metabolismo , Artéria Pulmonar/patologia , Artéria Pulmonar/fisiopatologia , Proteína 3 de Ligação a Fator de Crescimento Semelhante à Insulina/metabolismo , Proteína 3 de Ligação a Fator de Crescimento Semelhante à Insulina/genética , Proteína 2 de Ligação a Fator de Crescimento Semelhante à Insulina/metabolismo , Proteína 2 de Ligação a Fator de Crescimento Semelhante à Insulina/genética , Fator de Crescimento Insulin-Like I/metabolismo , Miócitos de Músculo Liso/metabolismo , Miócitos de Músculo Liso/patologia , Células Cultivadas , Masculino , Proteína 1 de Ligação a Fator de Crescimento Semelhante à Insulina/metabolismo , Proteína 1 de Ligação a Fator de Crescimento Semelhante à Insulina/genética , Fosforilação , Fator de Transcrição STAT3/metabolismo , Estudos de Casos e Controles , Camundongos Endogâmicos C57BL , Hipertensão Pulmonar Primária Familiar/metabolismo , Hipertensão Pulmonar Primária Familiar/fisiopatologia , Hipertensão Pulmonar Primária Familiar/patologia , Hipertensão Pulmonar Primária Familiar/genética , Feminino , Receptores ErbB/metabolismo , Pessoa de Meia-Idade , Remodelação Vascular , Adulto , Músculo Liso Vascular/metabolismo , Músculo Liso Vascular/patologiaRESUMO
Rationale: Idiopathic pulmonary arterial hypertension (IPAH) is characterized by extensive pulmonary vascular remodeling caused by plexiform and obliterative lesions, media hypertrophy, inflammatory cell infiltration, and alterations of the adventitia. Objective: We sought to test the hypothesis that microscopic IPAH vascular lesions express unique molecular profiles, which collectively are different from control pulmonary arteries. Methods: We used digital spatial transcriptomics to profile the genomewide differential transcriptomic signature of key pathological lesions (plexiform, obliterative, intima+media hypertrophy, and adventitia) in IPAH lungs (n = 11) and compared these data with the intima+media hypertrophy and adventitia of control pulmonary artery (n = 5). Measurements and Main Results: We detected 8,273 transcripts in the IPAH lesions and control lung pulmonary arteries. Plexiform lesions and IPAH adventitia exhibited the greatest number of differentially expressed genes when compared with intima+media hypertrophy and obliterative lesions. Plexiform lesions in IPAH showed enrichment for 1) genes associated with transforming growth factor ß signaling and 2) mutated genes affecting the extracellular matrix and endothelial-mesenchymal transformation. Plexiform lesions and IPAH adventitia showed upregulation of genes involved in immune and IFN signaling, coagulation, and complement pathways. Cellular deconvolution indicated variability in the number of vascular and inflammatory cells between IPAH lesions, which underlies the differential transcript profiling. Conclusions: IPAH lesions express unique molecular transcript profiles enriched for pathways involving pathogenetic pathways, including genetic disease drivers, innate and acquired immunity, hypoxia sensing, and angiogenesis signaling. These data provide a rich molecular-structural framework in IPAH vascular lesions that inform novel biomarkers and therapeutic targets in this highly morbid disease.
Assuntos
Artéria Pulmonar , Humanos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Artéria Pulmonar/patologia , Remodelação Vascular/genética , Perfilação da Expressão Gênica/métodos , Hipertensão Arterial Pulmonar/genética , Transcriptoma/genética , Hipertensão Pulmonar Primária Familiar/genética , Hipertensão Pulmonar Primária Familiar/fisiopatologiaRESUMO
BACKGROUND: Pathologic variants in the bone morphogenetic protein receptor-2 (BMPR2) gene cause a pulmonary arterial hypertension phenotype in an autosomal-dominant pattern with incomplete penetrance. Straight back syndrome is one of the causes of pseudo-heart diseases. To date, no cases of idiopathic or heritable pulmonary arterial hypertension with straight back syndrome have been reported. CASE PRESENTATION: A 30-year-old female was diagnosed with pulmonary arterial hypertension by right heart catheterization. Computed tomography revealed a decreased anteroposterior thoracic space with heart compression, indicating a straight back syndrome. Genetic analysis by whole exome sequencing identified a novel c.2423_2424delGT (p.G808Gfs*4) germline frameshift variant within BMPR2 affecting the cytoplasmic tail domain. CONCLUSIONS: This is the first report of different straight back characteristics in heritable pulmonary arterial hypertension with a novel germline BMPR2 variant. This finding may provide a new perspective on the variable penetrance of the pulmonary arterial hypertension phenotype.
Assuntos
Hipertensão Arterial Pulmonar , Feminino , Humanos , Adulto , Hipertensão Pulmonar Primária Familiar/genética , Hipertensão Arterial Pulmonar/genética , Fenótipo , Mutação , Receptores de Proteínas Morfogenéticas Ósseas Tipo II/genética , Receptores de Proteínas Morfogenéticas Ósseas Tipo II/metabolismoRESUMO
Asians have a higher carrier rate of pulmonary arterial hypertension (PAH)-related genetic variants than Caucasians do. This study aimed to identify PAH-related genetic variants using whole exome sequencing (WES) in Asian idiopathic and heritable PAH cohorts. A WES library was constructed, and candidate variants were further validated by polymerase chain reaction and Sanger sequencing in the PAH cohort. In a total of 69 patients, the highest incidence of variants was found in the BMPR2, ATP13A3, and GDF2 genes. Regarding the BMPR2 gene variants, there were two nonsense variants (c.994C>T, p. Arg332*; c.1750C>T, p. Arg584*), one missense variant (c.1478C>T, p. Thr493Ile), and one novel in-frame deletion variant (c.877_888del, p. Leu293_Ser296del). Regarding the GDF2 variants, there was one likely pathogenic nonsense variant (c.259C>T, p. Gln87*) and two missense variants (c.1207G>A, p. Val403Ile; c.38T>C, p. Leu13Pro). The BMPR2 and GDF2 variant subgroups had worse hemodynamics. Moreover, the GDF2 variant patients were younger and had a significantly lower GDF2 value (135.6 ± 36.2 pg/mL, p = 0.002) in comparison to the value in the non-BMPR2/non-GDF2 mutant group (267.8 ± 185.8 pg/mL). The BMPR2 variant carriers had worse hemodynamics compared to the patients with the non-BMPR2/non-GDF2 mutant group. Moreover, there was a significantly lower GDF2 value in the GDF2 variant carriers compared to the control group. GDF2 may be a protective or corrected modifier in certain genetic backgrounds.
Assuntos
Hipertensão Arterial Pulmonar , Humanos , Hipertensão Arterial Pulmonar/genética , Hipertensão Pulmonar Primária Familiar/genética , Mutação de Sentido Incorreto , Hemodinâmica , Deleção de Sequência , Receptores de Proteínas Morfogenéticas Ósseas Tipo II/genética , Mutação , Adenosina Trifosfatases/genética , Proteínas de Membrana Transportadoras/genética , Fator 2 de Diferenciação de Crescimento/genéticaRESUMO
BACKGROUND: Pulmonary arterial hypertension (PAH) exhibits phenotypic heterogeneity and variable response to therapy. The metabolome has been implicated in the pathogenesis of PAH, but previous works have lacked power to implicate specific metabolites. Mendelian randomization (MR) is a method for causal inference between exposures and outcomes. METHODS AND RESULTS: Using genome-wide association study summary statistics, we implemented MR analysis to test for potential causal relationships between serum concentration of 575 metabolites and PAH. Five metabolites were causally associated with the risk of PAH after multiple testing correction. Next, we measured serum concentration of candidate metabolites in an independent clinical cohort of 449 patients with PAH to check whether metabolite concentrations are correlated with markers of disease severity. Of the 5 candidates nominated by our MR work, serine was negatively associated and homostachydrine was positively associated with clinical severity of PAH via direct measurement in this independent clinical cohort. Finally we used conditional and orthogonal approaches to explore the biology underlying our lead metabolites. Rare variant burden testing was carried out using whole exome sequencing data from 578 PAH cases and 361 675 controls. Multivariable MR is an extension of MR that uses a single set of instrumental single-nucleotide polymorphisms to measure multiple exposures; multivariable MR is used to determine interdependence between the effects of different exposures on a single outcome. Rare variant analysis demonstrated that loss-of-function mutations within activating transcription factor 4, a transcription factor responsible for upregulation of serine synthesis under conditions of serine starvation, are associated with higher risk for PAH. Homostachydrine is a xenobiotic metabolite that is structurally related to l-proline betaine, which has previously been linked to modulation of inflammation and tissue remodeling in PAH. Our multivariable MR analysis suggests that the effect of l-proline betaine is actually mediated indirectly via homostachydrine. CONCLUSIONS: Our data present a method for study of the metabolome in the context of PAH, and suggests several candidates for further evaluation and translational research.
Assuntos
Hipertensão Arterial Pulmonar , Humanos , Hipertensão Arterial Pulmonar/genética , Estudo de Associação Genômica Ampla , Análise da Randomização Mendeliana , Seguimentos , Hipertensão Pulmonar Primária Familiar/genética , SerinaRESUMO
BACKGROUND: Mutations in the T-Box 4 (TBX4) gene are a lesser-known cause of heritable pulmonary arterial hypertension (PAH). Patients with heritable PAH typically have worse outcomes when compared with patients with idiopathic PAH, yet little is known about the phenotypical presentation of this mutation. OBJECTIVE: This article reviews the pattern of chest CT findings in pediatric patients with PAH and TBX4 mutations and compares their radiographic presentation with those of age-matched patients with PAH but without TBX4 mutations. MATERIALS AND METHODS: A retrospective chart review of the pulmonary arterial hypertension database was performed. Pediatric patients with PAH-confirmed TBX4 mutations and an available high CT were included. Fifteen (9 females) patients met the inclusion criteria. Fourteen (8 females) age-matched controls with diagnosed PAH but without TBX4 mutations were also evaluated. The median age at diagnosis was 7.4 years (range: 0.1-16.4 years). Demographic information and clinical outcomes were collected. CTs of the chest were reviewed for multiple airway, parenchymal, and structural abnormalities (16 imaging findings in total). Chi-square tests were used to compare the prevalence of each imaging finding in the TBX4 cohort compared to the control group. RESULTS: Patients with TBX-4 mutations had increased presence of peripheral or subpleural irregularity (73% vs 0%, P < 0.01), cystic lucencies (67% vs 7%, P < 0.01), and linear or reticular opacity (53% vs 0%, P < 0.01) compared to the control group. Ground glass opacities, bronchiectasis, and centrilobular nodules were not significantly different between the two patient groups (P > 0.05). CONCLUSION: TBX4 mutations have distinct imaging phenotypes in pediatric patients with PAH. Compared to patients without this mutation, patients with TBX-4 genes typically present with peripheral or subpleural irregularity, cystic lucencies, and linear or reticular opacity.
Assuntos
Hipertensão Pulmonar , Hipertensão Arterial Pulmonar , Feminino , Humanos , Criança , Lactente , Pré-Escolar , Adolescente , Estudos Retrospectivos , Artéria Pulmonar , Hipertensão Pulmonar/diagnóstico por imagem , Hipertensão Pulmonar/genética , Hipertensão Pulmonar Primária Familiar/genética , Mutação , Tomografia Computadorizada por Raios X , Proteínas com Domínio T/genéticaRESUMO
Rationale: Unraveling immune-driven vascular pathology in pulmonary arterial hypertension (PAH) requires a comprehensive understanding of the immune cell landscape. Although patients with hereditary (H)PAH and bone morphogenetic protein receptor type 2 (BMPR2) mutations have more severe pulmonary vascular pathology, it is not known whether this is related to specific immune cell subsets. Objectives: This study aims to elucidate immune-driven vascular pathology by identifying immune cell subtypes linked to severity of pulmonary arterial lesions in PAH. Methods: We used cutting-edge multiplexed ion beam imaging by time of flight to compare pulmonary arteries (PAs) and adjacent tissue in PAH lungs (idiopathic [I]PAH and HPAH) with unused donor lungs, as controls. Measurements and Main Results: We quantified immune cells' proximity and abundance, focusing on those features linked to vascular pathology, and evaluated their impact on pulmonary arterial smooth muscle cells (SMCs) and endothelial cells. Distinct immune infiltration patterns emerged between PAH subtypes, with intramural involvement independently linked to PA occlusive changes. Notably, we identified monocyte-derived dendritic cells within PA subendothelial and adventitial regions, influencing vascular remodeling by promoting SMC proliferation and suppressing endothelial gene expression across PAH subtypes. In patients with HPAH, pronounced immune dysregulation encircled PA walls, characterized by heightened perivascular inflammation involving T cell immunoglobulin and mucin domain-3 (TIM-3)+ T cells. This correlated with an expanded DC subset expressing indoleamine 2,3-dioxygenase 1, TIM-3, and SAM and HD domain-containing deoxynucleoside triphosphate triphosphohydrolase 1, alongside increased neutrophils, SMCs, and alpha-smooth muscle actin (ACTA2)+ endothelial cells, reinforcing the heightened severity of pulmonary vascular lesions. Conclusions: This study presents the first architectural map of PAH lungs, connecting immune subsets not only with specific PA lesions but also with heightened severity in HPAH compared with IPAH. Our findings emphasize the therapeutic potential of targeting monocyte-derived dendritic cells, neutrophils, cellular interactions, and immune responses to alleviate severe vascular pathology in IPAH and HPAH.
Assuntos
Hidralazina/análogos & derivados , Hipertensão Pulmonar , Hipertensão Arterial Pulmonar , Humanos , Receptor Celular 2 do Vírus da Hepatite A/metabolismo , Células Endoteliais/metabolismo , Hipertensão Pulmonar Primária Familiar/genética , Artéria Pulmonar , Receptores de Proteínas Morfogenéticas Ósseas Tipo II/genética , Proliferação de Células , HidrazonasRESUMO
Tbx4 protein, expressed in mesenchyme of the developing lung, contributes to airway branching and distal lung growth. An association between pediatric onset of pulmonary arterial hypertension (PAH) and genetic variations coding for the T-box transcription factor 4 gene (TBX4) has been increasingly recognized. Tbx4-related PAH onset has a bimodal age distribution, including severe to lethal PAH in newborns and later onset PAH. We present an autopsy study of a 24-year-old male with a heterozygous TBX4 variant, who developed pulmonary arterial hypertension at age 12 years. This unique case highlights the complex pulmonary histopathology leading to lethal cardiopulmonary failure in the setting of TBX4 mutation.
Assuntos
Mutação em Linhagem Germinativa , Hipertensão Arterial Pulmonar , Masculino , Criança , Humanos , Recém-Nascido , Adulto Jovem , Adulto , Hipertensão Arterial Pulmonar/metabolismo , Proteínas com Domínio T/genética , Proteínas com Domínio T/metabolismo , Pulmão , Mutação , Fenótipo , Hipertensão Pulmonar Primária Familiar/genética , Hipertensão Pulmonar Primária Familiar/metabolismo , Fatores de Transcrição/genéticaRESUMO
Heritable pulmonary arterial hypertension (HPAH) is a rare type of pulmonary arterial hypertension that often presents with progressive exertional dyspnea and for which there is no significant effective drug. A HPAH patient was admitted to our hospital more than three years ago, and the gene mutation was bone morphogenetic protein 2 (BMPR2). For the first 45 months, she was given oral imatinib 100 mg once daily, and her symptoms and hemodynamics improved significantly, with no apparent side effects. It is reported that, in combination with the characteristics of the case and related literatures, it provides clinicians with other feasible treatment options for HPAH.
Assuntos
Hipertensão Pulmonar , Humanos , Feminino , Hipertensão Pulmonar Primária Familiar/genética , Hipertensão Pulmonar/tratamento farmacológico , Hipertensão Pulmonar/genética , Mesilato de Imatinib/uso terapêutico , Mutação , Receptores de Proteínas Morfogenéticas Ósseas Tipo II/genética , Receptores de Proteínas Morfogenéticas Ósseas Tipo II/metabolismoRESUMO
BACKGROUND: Little is known about the effectiveness of treprostinil in higher-risk paediatric patients with various pulmonary arterial hypertension genotypes. This study was designed to investigate the prognosis of higher-risk paediatric patients with idiopathic or heritable pulmonary arterial hypertension (IPAH/HPAH) after treprostinil therapy. METHODS: Children with IPAH/HPAH who were stratified as higher risk and treated with treprostinil in our centre were included as the study cohort. Those who received only oral medications were included as the reference cohort. All patients in the study cohort received PAH-related genotyping. Survival was defined as no death. Event-free survival was defined as no death, Potts shunt, or atrial septostomy. RESULTS: Forty-nine children (median age 7.7 years [interquartile range (IQR) 4.2-11.5 years], 65% female) were included in the study cohort and 48 children were included in the reference cohort; 84% of the study cohort had genetic disorders after genetic testing with a dominance of BMPR2 and ACVRL1 mutations. After a median therapy duration of 5.56 months (IQR 2.66-11.12 months), all patients were alive with significant improvements in clinical characteristics. One-, 2-, and 3-year survival rates were 91%, 84%, and 69%, respectively with a median follow-up duration of 19.17 months (IQR 9.7-29.79 months), which was significantly superior to the reference cohort (P = 0.038). Multivariate Cox regression analysis identified World Health Organisation functional class after therapy as a predictor for survival. There was no significant difference in survival among patients with different genotypes. CONCLUSIONS: Treprostinil can significantly improve the prognosis in children with IPAH/HPAH who are at higher risk, despite genetic backgrounds.
Assuntos
Epoprostenol/análogos & derivados , Hidralazina/análogos & derivados , Hipertensão Pulmonar , Humanos , Criança , Feminino , Pré-Escolar , Masculino , Hipertensão Pulmonar Primária Familiar/tratamento farmacológico , Hipertensão Pulmonar Primária Familiar/genética , Epoprostenol/uso terapêutico , Epoprostenol/efeitos adversos , Estudos Retrospectivos , Receptores de Activinas Tipo II/uso terapêutico , HidrazonasRESUMO
The recently published new European guidelines for diagnosis and treatment of pulmonary hypertension now offer the so far most extensive description of genetic testing and counselling for pulmonary arterial hypertension patients. In addition, the importance of a clinical screening of healthy mutation carriers is highlighted as well as the genetic testing of patients with a suspicion of pulmonary veno-occlusive disease. We frame the respective parts of the guidelines on genetic testing and counselling in the context of recent data and provide comments. Finally, we give an outlook on novel molecular approaches starting from Sotatercept, addressing ion channels and novel therapeutic developments.
Assuntos
Hipertensão Pulmonar , Hipertensão Arterial Pulmonar , Pneumopatia Veno-Oclusiva , Humanos , Hipertensão Pulmonar Primária Familiar/diagnóstico , Hipertensão Pulmonar Primária Familiar/genética , Hipertensão Pulmonar Primária Familiar/terapia , Hipertensão Pulmonar/diagnóstico , Hipertensão Pulmonar/genética , Hipertensão Pulmonar/terapia , Pneumopatia Veno-Oclusiva/diagnóstico , Pneumopatia Veno-Oclusiva/genética , Pneumopatia Veno-Oclusiva/terapiaRESUMO
Pulmonary arterial hypertension (PAH) is a rare disease that can be caused by (likely) pathogenic germline genomic variants. In addition to the most prevalent disease gene, BMPR2 (bone morphogenetic protein receptor 2), several genes, some belonging to distinct functional classes, are also now known to predispose to the development of PAH. As a consequence, specialist and non-specialist clinicians and healthcare professionals are increasingly faced with a range of questions regarding the need for, approaches to and benefits/risks of genetic testing for PAH patients and/or related family members. We provide a consensus-based approach to recommendations for genetic counselling and assessment of current best practice for disease gene testing. We provide a framework and the type of information to be provided to patients and relatives through the process of genetic counselling, and describe the presently known disease causal genes to be analysed. Benefits of including molecular genetic testing within the management protocol of patients with PAH include the identification of individuals misclassified by other diagnostic approaches, the optimisation of phenotypic characterisation for aggregation of outcome data, including in clinical trials, and importantly through cascade screening, the detection of healthy causal variant carriers, to whom regular assessment should be offered.
Assuntos
Hipertensão Pulmonar , Hipertensão Arterial Pulmonar , Humanos , Aconselhamento Genético/métodos , Hipertensão Arterial Pulmonar/genética , Hipertensão Pulmonar/diagnóstico , Hipertensão Pulmonar/genética , Hipertensão Pulmonar/terapia , Mutação , Hipertensão Pulmonar Primária Familiar/diagnóstico , Hipertensão Pulmonar Primária Familiar/genética , Testes Genéticos/métodos , Predisposição Genética para DoençaRESUMO
Approximately one-third of bone morphogenic protein receptor-2 (BMPR2) mutation carriers develop pulmonary arterial hypertension (PAH), which indicates that additional risk factors are needed for the manifestation of the disease. It is questionable whether pregnancy is a risk factor for PAH development in these patients. We represent a 30-year-old woman with a heterozygous BMPR2 mutation who was diagnosed with PAH during the postpartum period and reviewed the literature in this report. We also discussed the possible underlying mechanisms that might have resulted in PAH development during pregnancy in BMPR2 mutation carriers.
Assuntos
Hipertensão Pulmonar , Hipertensão Arterial Pulmonar , Gravidez , Feminino , Humanos , Adulto , Hipertensão Pulmonar Primária Familiar/diagnóstico , Hipertensão Pulmonar Primária Familiar/genética , Hipertensão Pulmonar/diagnóstico , Hipertensão Pulmonar/genética , Mutação , Período Pós-Parto , Receptores de Proteínas Morfogenéticas Ósseas Tipo II/genética , Receptores de Proteínas Morfogenéticas Ósseas Tipo II/metabolismoRESUMO
Idiopathic pulmonary arterial hypertension (IPAH) is a serious and fatal disease. Recently, m6A has been reported to play an important role in the lungs of IPAH patients and experimental pulmonary hypertension models. However, the meaning of m6A mRNAs in the peripheral blood of IPAH patients remains largely unexplored. We aimed to construct a transcriptome-wide map of m6A mRNAs in the peripheral blood of IPAH patients. M6A RNA Methylation Quantification Kit was utilized to measure the total m6A levels in the peripheral blood of IPAH patients. A combination of MeRIP-seq, RNA-seq and bioinformatics analysis was utilized to select m6A-modified hub genes of IPAH. MeRIP-qPCR and RT-qPCR were used to measure the m6A levels and mRNA levels of TP53, RPS27A, SMAD3 and FoxO3 in IPAH patients. Western blot was performed to assess the protein levels of m6A related regulators and m6A related genes in experimental PH animal models, hypoxia-treated and PDGF-BB induced PASMCs. We found that the total m6A levels were increased in peripheral blood of IPAH patients and verified that m6A levels of RPS27A and SMAD3 were significantly elevated and m6A levels of TP53 and FoxO3 were significantly reduced. The mRNA or protein levels of RPS27A, SMAD3, TP53 and FoxO3 were changed in human blood samples, experimental PH animal models and PDGF-BB induced PASMCs. Moreover, METTL3 and YTHDF1 were increased in the hypoxia induced pulmonary hypertension rat model, hypoxia-treated and PDGF-BB induced PASMCs. These finding suggested that m6A may play an important role in IPAH.