| 1. |
- Dahan, Diana, et al.
(författare)
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MicroRNA-Dependent Control of Serotonin-Induced Pulmonary Arterial Contraction
- 2017
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Ingår i: Journal of Vascular Research. - : S. Karger AG. - 1018-1172 .- 1423-0135. ; 54:4, s. 246-256
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Tidskriftsartikel (refereegranskat)abstract
- Background: Serotonin (5-HT) is considered to play a role in pulmonary arterial hypertension by regulating vascular remodeling and smooth muscle contractility. Here, arteries from mice with inducible and smooth muscle-specific deletion of Dicer were used to address mechanisms by which microRNAs control 5-HT-induced contraction. Methods: Mice were used 5 weeks after Dicer deletion, and pulmonary artery contractility was analyzed by wire myography. Results: No change was seen in right ventricular systolic pressure following dicer deletion, but systemic blood pressure was reduced. Enhanced 5-HT-induced contraction in Dicer KO pulmonary arteries was associated with increased 5-HT2A receptor mRNA expression whereas 5-HT1B and 5-HT2B receptor mRNAs were unchanged. Contraction by the 5-HT2A agonist TCB-2 was increased in Dicer KO as was the response to the 5-HT2B agonist BW723C86. Effects of Src and protein kinase C inhibition were similar in control and KO arteries, but the effect of inhibition of Rho kinase was reduced. We identified miR-30c as a potential candidate for 5-HT2A receptor regulation as it repressed 5-HT2A mRNA and protein. Conclusion: Our findings show that 5-HT receptor signaling in the arterial wall is subject to regulation by microRNAs and that this entails altered 5-HT2A receptor expression and signaling.
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| 2. |
- Chang, Ya-Ting, et al.
(författare)
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Perlecan heparan sulfate deficiency impairs pulmonary vascular development and attenuates hypoxic pulmonary hypertension
- 2015
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Ingår i: Cardiovascular Research. - : Oxford University Press (OUP). - 0008-6363 .- 1755-3245. ; 107:1, s. 20-31
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Tidskriftsartikel (refereegranskat)abstract
- Aims Excessive vascular cell proliferation is an important component of pulmonary hypertension (PH). Perlecan is the major heparan sulfate (HS) proteoglycan in the vascular extracellular matrix. It binds growth factors, including FGF2, and either restricts or promotes cell proliferation. In this study, we have explored the effects of perlecan HS deficiency on pulmonary vascular development and in hypoxia-induced PH. Methods and results In normoxia, Hspg2(Delta 3/Delta 3) mice, deficient in perlecan HS, had reduced pericytes and muscularization of intra-acinar vessels. Pulmonary angiography revealed a peripheral perfusion defect. Despite these abnormalities, right ventricular systolic pressure (RVSP) and myocardial mass remained normal. After 4 weeks of hypoxia, increases in the proportion of muscularized vessels, RVSP, and right ventricular hypertrophy were significantly less in Hspg2(Delta 3/Delta 3) compared with wild type. The early phase of hypoxia induced a significantly lower increase in fibroblast growth factor receptor-1 (FGFR1) protein level and receptor phosphorylation, and reduced pulmonary artery smooth muscle cell (PASMC) proliferation in Hspg2(Delta 3/Delta 3). At 4 weeks, FGF2 mRNA and protein were also significantly reduced in Hspg2(Delta 3/Delta 3) lungs. Ligand and carbohydrate engagement assay showed that perlecan HS is required for HS-FGF2-FGFR1 ternary complex formation. In vitro, proliferation assays showed that PASMC proliferation is reduced by selective FGFR1 inhibition. PASMC adhesion to fibronectin was higher in Hspg2(Delta 3/Delta 3) compared with wild type. Conclusions Perlecan HS chains are important for normal vascular arborization and recruitment of pericytes to pulmonary vessels. Perlecan HS deficiency also attenuates hypoxia-induced PH, where the underlying mechanisms involve impaired FGF2/FGFR1 interaction, inhibition of PASMC growth, and altered cell-matrix interactions.
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| 3. |
- Chang, Ya-Ting, et al.
(författare)
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Versican accumulates in vascular lesions in pulmonary arterial hypertension
- 2016
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Ingår i: PULMONARY CIRCULATION. - : Wiley. - 2045-8932 .- 2045-8940. ; 6:3, s. 347-359
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Tidskriftsartikel (refereegranskat)abstract
- Pulmonary arterial hypertension (PAH) is a lethal condition for which there is no effective curative pharmacotherapy. PAH is characterized by vasoconstriction, wall thickening of pulmonary arteries, and increased vascular resistance. Versican is a chondroitin sulfate proteoglycan in the vascular extracellular matrix that accumulates following vascular injury and promotes smooth-muscle cell proliferation in systemic arteries. Here, we investigated whether versican may play a similar role in PAH. Paraffin-embedded lung sections from patients who underwent lung transplantation to treat PAH were used for immunohistochemistry. The etiologies of PAH in the subjects involved in this study were idiopathic PAH, scleroderma, and congenital heart disease (atrial septal defect) with left-to-right shunt. Independent of the underlying etiology, increased versican immunostaining was observed in areas of medial thickening, in neointima, and in plexiform lesions. Western blot of lung tissue lysates confirmed accumulation of versican in patients with PAH. Double staining for versican and CD45 showed only occasional colocalization in neointima of high-grade lesions and plexiform lesions. In vitro, metabolic labeling with [S-35] sulfate showed that human pulmonary artery smooth-muscle cells (hPASMCs) produce mainly chondroitin sulfate glycosaminoglycans. In addition, hypoxia, but not cyclic stretch, was demonstrated to increase both versican messenger RNA expression and protein synthesis by hPASMCs. Versican accumulates in vascular lesions of PAH, and the amount of versican correlates more with lesion severity than with underlying etiology or inflammation. Hypoxia is a possible regulator of versican accumulation, which may promote proliferation of pulmonary smooth-muscle cells and vascular remodeling in PAH.
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| 4. |
- Hansmann, Georg, et al.
(författare)
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2019 updated consensus statement on the diagnosis and treatment of pediatric pulmonary hypertension: The European Pediatric Pulmonary Vascular Disease Network (EPPVDN), endorsed by AEPC, ESPR and ISHLT
- 2019
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Ingår i: The Journal of Heart and Lung Transplantation. - : Elsevier BV. - 1053-2498. ; 38:9, s. 879-901
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Forskningsöversikt (refereegranskat)abstract
- © 2019 The European Pediatric Pulmonary Vascular Disease Network is a registered, non-profit organization that strives to define and develop effective, innovative diagnostic methods and treatment options in all forms of pediatric pulmonary hypertensive vascular disease, including pulmonary hypertension (PH) associated with bronchopulmonary dysplasia, PH associated with congenital heart disease (CHD), persistent PH of the newborn, and related cardiac dysfunction. The executive writing group members conducted searches of the PubMed/MEDLINE bibliographic database (1990–2018) and held face-to-face and web-based meetings. Ten section task forces voted on the updated recommendations, based on the 2016 executive summary. Clinical trials, meta-analyses, guidelines, and other articles that include pediatric data were searched using the term “pulmonary hypertension” and other keywords. Class of recommendation (COR) and level of evidence (LOE) were assigned based on European Society of Cardiology/American Heart Association definitions and on pediatric data only, or on adult studies that included >10% children or studies that enrolled adults with CHD. New definitions by the World Symposium on Pulmonary Hypertension 2018 were included. We generated 10 tables with graded recommendations (COR/LOE). The topics include diagnosis/monitoring, genetics/biomarkers, cardiac catheterization, echocardiography, cardiac magnetic resonance/chest computed tomography, associated forms of PH, intensive care unit/lung transplantation, and treatment of pediatric PH. For the first time, a set of specific recommendations on the management of PH in middle- and low-income regions was developed. Taken together, these executive, up-to-date guidelines provide a specific, comprehensive, detailed but practical framework for the optimal clinical care of children and young adults with PH.
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| 5. |
- Tannenberg, Philip, et al.
(författare)
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Extracellular retention of PDGF-B directs vascular remodeling in mouse hypoxia-induced pulmonary hypertension
- 2018
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Ingår i: American Journal of Physiology - Lung cellular and Molecular Physiology. - : AMER PHYSIOLOGICAL SOC. - 1040-0605 .- 1522-1504. ; 314:4, s. 1593-1605
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Tidskriftsartikel (refereegranskat)abstract
- Pulmonary hypertension (PH) is a lethal condition, and current vasodilator therapy has limited effect. Antiproliferative strategies targeting platelet-derived growth factor (PDGF) receptors, such as imatinib, have generated promising results in animal studies. Imatinib is, however, a nonspecific tyrosine kinase inhibitor and has in clinical studies caused unacceptable adverse events. Further studies are needed on the role of PDGF signaling in PH. Here, mice expressing a variant of PDGF-B with no retention motif (Pdgfb(ret/ret)), resulting in defective binding to extracellular matrix, were studied. Following 4 wk of hypoxia, right ventricular systolic pressure, right ventricular hypertrophy, and vascular remodeling were examined. Pdgfb(ret/ret) mice did not develop PH, as assessed by hemodynamic parameters. Hypoxia did, however, induce vascular remodeling in Pdgfb(ret/ret) mice; but unlike the situation in controls where the remodeling led to an increased concentric muscularization of arteries, the vascular remodeling in Pdgfb(ret/ret) mice was characterized by a diffuse muscularization, in which cells expressing smooth muscle cell markers were found in the interalveolar septa detached from the normally muscularized intra-acinar vessels. Additionally, fewer NG2-positive perivascular cells were found in Pdgfb(ret/ret) lungs, and mRNA analyses showed significantly increased levels of Il6 following hypoxia, a known promigratory factor for pericytes. No differences in proliferation were detected at 4 wk. This study emphasizes the importance of extracellular matrix-growth factor interactions and adds to previous knowledge of PDGF-B in PH pathobiology. In summary, Pdgfb(ret/ret) mice have unaltered hemodynamic parameters following chronic hypoxia, possibly secondary to a disorganized vascular muscularization.
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