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Papaioannou I, Dritsoula A, Kang P, Baliga RS, Trinder SL, Cook E, Xu S, Hobbs A, Denton CP, Abraham DJ, Ponticos M. NKX2-5 regulates vessel remodelling in scleroderma-associated pulmonary arterial hypertension. JCI Insight 2024:e164191. [PMID: 38652537 DOI: 10.1172/jci.insight.164191] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/25/2024] Open
Abstract
NKX2-5 is a member of the homeobox-containing transcription factors critical in regulating tissue differentiation in development. Here, we report a role for NKX2-5 in vascular smooth muscle cell phenotypic modulation in vitro and in vascular remodelling in vivo. NKX2-5 is up-regulated in scleroderma (SSc) patients with pulmonary arterial hypertension. Suppression of NKX2-5 expression in smooth muscle cells, halted vascular smooth muscle proliferation and migration, enhanced contractility and blocked the expression of the extracellular matrix genes. Conversely, overexpression of NKX2-5 suppressed the expression of contractile genes (ACTA2, TAGLN, CNN1) and enhanced the expression of matrix genes (COL1) in vascular smooth muscle cells. In vivo, conditional deletion of NKX2-5 attenuated blood vessel remodelling and halted the progression to hypertension in the mouse chronic hypoxia mouse model. This study revealed that signals related to injury such as serum and low confluence, which induce NKX2-5 expression in cultured cells, is potentiated by TGFβ and further enhanced by hypoxia. The effect of TGFβ was sensitive to ERK5 and PI3K inhibition. Our data suggest a pivotal role for NKX2-5 in the phenotypic modulation of smooth muscle cells during pathological vascular remodelling and provide proof of concept for therapeutic targeting of NKX2-5 in vasculopathies.
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Affiliation(s)
- Ioannis Papaioannou
- Division of Medicine, Department of Inflammation, University College London, London, United Kingdom
| | - Athina Dritsoula
- Division of Medicine, Department of Inflammation, University College London, London, United Kingdom
| | - Ping Kang
- Division of Medicine, Department of Inflammation, University College London, London, United Kingdom
| | - Reshma S Baliga
- William Harvey Research Institute, Barts and The London School of Medicine , Queen Mary University of London, London, United Kingdom
| | - Sarah L Trinder
- Division of Medicine, Department of Inflammation, University College London, London, United Kingdom
| | - Emma Cook
- Division of Medicine, Department of Inflammation, University College London, London, United Kingdom
| | - Shiwen Xu
- Division of Medicine, Department of Inflammation, University College London, London, United Kingdom
| | - Adrian Hobbs
- William Harvey Research Institute, Barts and The London School of Medicine , Queen Mary University of London, London, United Kingdom
| | - Christopher P Denton
- Division of Medicine, Department of Inflammation, University College London, London, United Kingdom
| | - David J Abraham
- Division of Medicine, Department of Inflammation, University College London, London, United Kingdom
| | - Markella Ponticos
- Division of Medicine, Department of Inflammation, University College London, London, United Kingdom
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Tam AYY, Horwell AL, Trinder SL, Khan K, Xu S, Ong V, Denton CP, Norman JT, Holmes AM, Bou-Gharios G, Abraham DJ. Selective deletion of connective tissue growth factor attenuates experimentally-induced pulmonary fibrosis and pulmonary arterial hypertension. Int J Biochem Cell Biol 2021; 134:105961. [PMID: 33662577 PMCID: PMC8111417 DOI: 10.1016/j.biocel.2021.105961] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2020] [Revised: 02/15/2021] [Accepted: 02/16/2021] [Indexed: 12/17/2022]
Abstract
Connective tissue growth factor (CTGF, CCN2) is a matricellular protein which plays key roles in normal mammalian development and in tissue homeostasis and repair. In pathological conditions, dysregulated CCN2 has been associated with cancer, cardiovascular disease, and tissue fibrosis. In this study, genetic manipulation of the CCN2 gene was employed to investigate the role of CCN2 expression in vitro and in experimentally-induced models of pulmonary fibrosis and pulmonary arterial hypertension (PAH). Knocking down CCN2 using siRNA reduced expression of pro-fibrotic markers (fibronectin p < 0.01, collagen type I p < 0.05, α-SMA p < 0.0001, TIMP-1 p < 0.05 and IL-6 p < 0.05) in TGF-β-treated lung fibroblasts derived from systemic sclerosis patients. In vivo studies were performed in mice using a conditional gene deletion strategy targeting CCN2 in a fibroblast-specific and time-dependent manner in two models of lung disease. CCN2 deletion significantly reduced pulmonary interstitial scarring and fibrosis following bleomycin-instillation, as assessed by fibrotic scores (wildtype bleomycin 3.733 ± 0.2667 vs CCN2 knockout (KO) bleomycin 4.917 ± 0.3436, p < 0.05) and micro-CT. In the well-established chronic hypoxia/Sugen model of pulmonary hypertension, CCN2 gene deletion resulted in a significant decrease in pulmonary vessel remodelling, less right ventricular hypertrophy and a reduction in the haemodynamic measurements characteristic of PAH (RVSP and RV/LV + S were significantly reduced (p < 0.05) in CCN2 KO compared to WT mice in hypoxic/SU5416 conditions). These results support a prominent role for CCN2 in pulmonary fibrosis and in vessel remodelling associated with PAH. Therefore, therapeutics aimed at blocking CCN2 function are likely to benefit several forms of severe lung disease.
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Affiliation(s)
- Angela Y Y Tam
- Centre for Rheumatology and Connective Tissue Disease, Department of Inflammation, Division of Medicine, University College London, London, NW3 2PF, UK.
| | - Amy L Horwell
- Department of Musculoskeletal and Ageing Science, Institute of Life Course and Medical Sciences, University of Liverpool, Liverpool, L7 8TX, UK
| | - Sarah L Trinder
- Centre for Rheumatology and Connective Tissue Disease, Department of Inflammation, Division of Medicine, University College London, London, NW3 2PF, UK
| | - Korsa Khan
- Centre for Rheumatology and Connective Tissue Disease, Department of Inflammation, Division of Medicine, University College London, London, NW3 2PF, UK
| | - Shiwen Xu
- Centre for Rheumatology and Connective Tissue Disease, Department of Inflammation, Division of Medicine, University College London, London, NW3 2PF, UK
| | - Voon Ong
- Centre for Rheumatology and Connective Tissue Disease, Department of Inflammation, Division of Medicine, University College London, London, NW3 2PF, UK
| | - Christopher P Denton
- Centre for Rheumatology and Connective Tissue Disease, Department of Inflammation, Division of Medicine, University College London, London, NW3 2PF, UK
| | - Jill T Norman
- Department of Renal Medicine, Division of Medicine, University College London, London, NW3 2PF, UK
| | - Alan M Holmes
- Centre for Rheumatology and Connective Tissue Disease, Department of Inflammation, Division of Medicine, University College London, London, NW3 2PF, UK
| | - George Bou-Gharios
- Department of Musculoskeletal and Ageing Science, Institute of Life Course and Medical Sciences, University of Liverpool, Liverpool, L7 8TX, UK
| | - David J Abraham
- Centre for Rheumatology and Connective Tissue Disease, Department of Inflammation, Division of Medicine, University College London, London, NW3 2PF, UK
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Evans DL, Bailey SG, Thumser AE, Trinder SL, Winstone NE, Bailey IG. The Biochemical Literacy Framework: Inviting pedagogical innovation in higher education. FEBS Open Bio 2020; 10:1720-1736. [PMID: 32696491 PMCID: PMC7459419 DOI: 10.1002/2211-5463.12938] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2020] [Revised: 06/22/2020] [Accepted: 07/17/2020] [Indexed: 11/08/2022] Open
Abstract
When developing meaningful curricula, institutions must engage with the desired disciplinary attributes of their graduates. Successfully employed in several areas, including psychology and chemistry, disciplinary literacies provide structure for the development of core competencies-pursuing progressive education. To this end, we have sought to develop a comprehensive blueprint of a graduate biochemist, providing detailed insight into the development of skills in the context of disciplinary knowledge. The Biochemical Literacy Framework (BCLF) aspires to encourage innovative course design in both the biochemical field and beyond through stimulating discussion among individuals developing undergraduate biochemistry degree courses based on pedagogical best practice. Here, we examine the concept of biochemical literacy aiming to start answering the question: What must individuals do and know to approach and transform ideas in the context of the biochemical sciences? The BCLF began with the guidance published by relevant learned societies - including the Royal Society of Biology, the Biochemical Society, the American Society for Biochemistry and Molecular Biology and the Quality Assurance Agency, before considering relevant pedagogical literature. We propose that biochemical literacy is comprised of seven key skills: critical thinking, self-management, communication, information literacy, visual literacy, practical skills and content knowledge. Together, these form a dynamic, highly interconnected and interrelated meta-literacy supporting the use of evidence-based, robust learning techniques. The BCLF is intended to form the foundation for discussion between colleagues, in addition to forming the groundwork for both pragmatic and exploratory future studies into facilitating and further defining biochemical literacy.
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Affiliation(s)
| | - Sarah G. Bailey
- Department of Biochemical SciencesUniversity of SurreyGuildfordUK
| | | | - Sarah L. Trinder
- Department of Biochemical SciencesUniversity of SurreyGuildfordUK
| | | | - Ian G. Bailey
- Department of Biochemical SciencesUniversity of SurreyGuildfordUK
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Good RB, Gilbane AJ, Trinder SL, Denton CP, Coghlan G, Abraham DJ, Holmes AM. Endothelial to Mesenchymal Transition Contributes to Endothelial Dysfunction in Pulmonary Arterial Hypertension. Am J Pathol 2015; 185:1850-8. [PMID: 25956031 DOI: 10.1016/j.ajpath.2015.03.019] [Citation(s) in RCA: 227] [Impact Index Per Article: 25.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/29/2014] [Revised: 02/03/2015] [Accepted: 03/03/2015] [Indexed: 12/16/2022]
Abstract
Pulmonary arterial hypertension (PAH) is a progressive disease characterized by lung endothelial cell dysfunction and vascular remodeling. Normally, the endothelium forms an integral cellular barrier to regulate vascular homeostasis. During embryogenesis endothelial cells exhibit substantial plasticity that contribute to cardiac development by undergoing endothelial-to-mesenchymal transition (EndoMT). We determined the presence of EndoMT in the pulmonary vasculature in vivo and the functional effects on pulmonary artery endothelial cells (PAECs) undergoing EndoMT in vitro. Histologic assessment of patients with systemic sclerosis-associated PAH and the hypoxia/SU5416 mouse model identified the presence von Willebrand factor/α-smooth muscle actin-positive endothelial cells in up to 5% of pulmonary vessels. Induced EndoMT in PAECs by inflammatory cytokines IL-1β, tumor necrosis factor α, and transforming growth factor β led to actin cytoskeleton reorganization and the development of a mesenchymal morphology. Induced EndoMT cells exhibited up-regulation of mesenchymal markers, including collagen type I and α-smooth muscle actin, and a reduction in endothelial cell and junctional proteins, including von Willebrand factor, CD31, occludin, and vascular endothelial-cadherin. Induced EndoMT monolayers failed to form viable biological barriers and induced enhanced leak in co-culture with PAECs. Induced EndoMT cells secreted significantly elevated proinflammatory cytokines, including IL-6, IL-8, and tumor necrosis factor α, and supported higher immune transendothelial migration compared with PAECs. These findings suggest that EndoMT may contribute to the development of PAH.
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Affiliation(s)
- Robert B Good
- Division of Medicine, University College London Medical School, Royal Free Campus, London, United Kingdom
| | - Adrian J Gilbane
- Division of Medicine, University College London Medical School, Royal Free Campus, London, United Kingdom
| | - Sarah L Trinder
- Division of Medicine, University College London Medical School, Royal Free Campus, London, United Kingdom
| | - Christopher P Denton
- Division of Medicine, University College London Medical School, Royal Free Campus, London, United Kingdom
| | - Gerry Coghlan
- National Pulmonary Hypertension Service, Royal Free Hospital National Health Service Foundation Trust, London, United Kingdom
| | - David J Abraham
- Division of Medicine, University College London Medical School, Royal Free Campus, London, United Kingdom
| | - Alan M Holmes
- Division of Medicine, University College London Medical School, Royal Free Campus, London, United Kingdom.
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Baliga RS, Scotton CJ, Trinder SL, Chambers RC, MacAllister RJ, Hobbs AJ. Intrinsic defence capacity and therapeutic potential of natriuretic peptides in pulmonary hypertension associated with lung fibrosis. Br J Pharmacol 2015; 171:3463-75. [PMID: 24641440 PMCID: PMC4105933 DOI: 10.1111/bph.12694] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2014] [Revised: 03/10/2014] [Accepted: 03/11/2014] [Indexed: 01/04/2023] Open
Abstract
BACKGROUND AND PURPOSE Idiopathic pulmonary fibrosis (IPF) is a progressive fibro-proliferative disorder refractory to current therapy commonly complicated by the development of pulmonary hypertension (PH); the associated morbidity and mortality are substantial. Natriuretic peptides possess vasodilator and anti-fibrotic actions, and pharmacological augmentation of their bioactivity ameliorates renal and myocardial fibrosis. Here, we investigated whether natriuretic peptides possess an intrinsic cytoprotective function preventing the development of pulmonary fibrosis and associated PH, and whether therapeutics targeting natriuretic peptide signalling demonstrate efficacy in this life-threatening disorder. EXPERIMENTAL APPROACH Pulmonary haemodynamics, right ventricular function and markers of lung fibrosis were determined in wild-type (WT) and natriuretic peptide receptor (NPR)-A knockout (KO) mice exposed to bleomycin (1 mg·kg−1). Human myofibroblast differentiation was studied in vitro. KEY RESULTS Exacerbated cardiac, vascular and fibrotic pathology was observed in NPR-A KO animals, compared with WT mice, exposed to bleomycin. Treatment with a drug combination that raised circulating natriuretic peptide levels (ecadotril) and potentiated natriuretic peptide-dependent signalling (sildenafil) reduced indices of disease progression, whether administered prophylactically or to animals with established lung disease. This positive pharmacodynamic effect was diminished in NPR-A KO mice. Atrial natriuretic peptide and sildenafil synergistically reduced TGFβ-induced human myofibroblast differentiation, a key driver of remodelling in IPF patients. CONCLUSIONS AND IMPLICATIONS These data highlight an endogenous host-defence capacity of natriuretic peptides in lung fibrosis and PH. A combination of ecadotril and sildenafil reversed the pulmonary haemodynamic aberrations and remodelling that characterize the disease, advocating therapeutic manipulation of natriuretic peptide bioactivity in patients with IPF.
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Affiliation(s)
- R S Baliga
- William Harvey Research Institute, Barts & The London School of Medicine, Queen Mary University of London, Charterhouse Square, London, UK
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Gilbane AJ, Derrett-Smith E, Trinder SL, Good RB, Pearce A, Denton CP, Holmes AM. Impaired Bone Morphogenetic Protein Receptor II Signaling in a Transforming Growth Factor-β–Dependent Mouse Model of Pulmonary Hypertension and in Systemic Sclerosis. Am J Respir Crit Care Med 2015; 191:665-77. [DOI: 10.1164/rccm.201408-1464oc] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
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Bubb KJ, Trinder SL, Baliga RS, Patel J, Clapp LH, MacAllister RJ, Hobbs AJ. Inhibition of phosphodiesterase 2 augments cGMP and cAMP signaling to ameliorate pulmonary hypertension. Circulation 2014; 130:496-507. [PMID: 24899690 DOI: 10.1161/circulationaha.114.009751] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
BACKGROUND Pulmonary hypertension (PH) is a life-threatening disorder characterized by increased pulmonary artery pressure, remodeling of the pulmonary vasculature, and right ventricular failure. Loss of endothelium-derived nitric oxide (NO) and prostacyclin contributes to PH pathogenesis, and current therapies are targeted to restore these pathways. Phosphodiesterases (PDEs) are a family of enzymes that break down cGMP and cAMP, which underpin the bioactivity of NO and prostacyclin. PDE5 inhibitors (eg, sildenafil) are licensed for PH, but a role for PDE2 in lung physiology and disease has yet to be established. Herein, we investigated whether PDE2 inhibition modulates pulmonary cyclic nucleotide signaling and ameliorates experimental PH. METHODS AND RESULTS The selective PDE2 inhibitor BAY 60-7550 augmented atrial natriuretic peptide- and treprostinil-evoked pulmonary vascular relaxation in isolated arteries from chronically hypoxic rats. BAY 60-7550 prevented the onset of both hypoxia- and bleomycin-induced PH and produced a significantly greater reduction in disease severity when given in combination with a neutral endopeptidase inhibitor (enhances endogenous natriuretic peptides), trepostinil, inorganic nitrate (NO donor), or a PDE5 inhibitor. Proliferation of pulmonary artery smooth muscle cells from patients with pulmonary arterial hypertension was reduced by BAY 60-7550, an effect further enhanced in the presence of atrial natriuretic peptide, NO, and treprostinil. CONCLUSIONS PDE2 inhibition elicits pulmonary dilation, prevents pulmonary vascular remodeling, and reduces the right ventricular hypertrophy characteristic of PH. This favorable pharmacodynamic profile is dependent on natriuretic peptide bioactivity and is additive with prostacyclin analogues, PDE5 inhibitor, and NO. PDE2 inhibition represents a viable, orally active therapy for PH.
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Affiliation(s)
- Kristen J Bubb
- From the William Harvey Research Institute, Barts and The London School of Medicine and Dentistry, Queen Mary University of London (K.J.B., S.L.T., R.S.B., A.J.H.); and Centre for Clinical Pharmacology, University College London (J.P., L.H.C., R.J.M.), London, United Kingdom
| | - Sarah L Trinder
- From the William Harvey Research Institute, Barts and The London School of Medicine and Dentistry, Queen Mary University of London (K.J.B., S.L.T., R.S.B., A.J.H.); and Centre for Clinical Pharmacology, University College London (J.P., L.H.C., R.J.M.), London, United Kingdom
| | - Reshma S Baliga
- From the William Harvey Research Institute, Barts and The London School of Medicine and Dentistry, Queen Mary University of London (K.J.B., S.L.T., R.S.B., A.J.H.); and Centre for Clinical Pharmacology, University College London (J.P., L.H.C., R.J.M.), London, United Kingdom
| | - Jigisha Patel
- From the William Harvey Research Institute, Barts and The London School of Medicine and Dentistry, Queen Mary University of London (K.J.B., S.L.T., R.S.B., A.J.H.); and Centre for Clinical Pharmacology, University College London (J.P., L.H.C., R.J.M.), London, United Kingdom
| | - Lucie H Clapp
- From the William Harvey Research Institute, Barts and The London School of Medicine and Dentistry, Queen Mary University of London (K.J.B., S.L.T., R.S.B., A.J.H.); and Centre for Clinical Pharmacology, University College London (J.P., L.H.C., R.J.M.), London, United Kingdom
| | - Raymond J MacAllister
- From the William Harvey Research Institute, Barts and The London School of Medicine and Dentistry, Queen Mary University of London (K.J.B., S.L.T., R.S.B., A.J.H.); and Centre for Clinical Pharmacology, University College London (J.P., L.H.C., R.J.M.), London, United Kingdom
| | - Adrian J Hobbs
- From the William Harvey Research Institute, Barts and The London School of Medicine and Dentistry, Queen Mary University of London (K.J.B., S.L.T., R.S.B., A.J.H.); and Centre for Clinical Pharmacology, University College London (J.P., L.H.C., R.J.M.), London, United Kingdom.
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Trinder SL, Shi-wen X, Ahned-Abdi B, Denton C, Budd DC, Abraham D, Holmes A. 304. Modulating the Fibrotic Effects of Fibrocytes from Scleroderma Patients. Rheumatology (Oxford) 2014. [DOI: 10.1093/rheumatology/keu127.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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Trinder SL, Shi-wen X, Abdi BA, Denton CP, Budd DC, Abraham DJ, Holmes AM. The role of endothelin receptors (ETRA/B) in fibrocyte differentiation. Life Sci 2013. [DOI: 10.1016/j.lfs.2013.12.143] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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Derrett-Smith EC, Dooley A, Gilbane AJ, Trinder SL, Khan K, Baliga R, Holmes AM, Hobbs AJ, Abraham D, Denton CP. Endothelial injury in a transforming growth factor β-dependent mouse model of scleroderma induces pulmonary arterial hypertension. Arthritis Rheum 2013; 65:2928-39. [PMID: 23839959 DOI: 10.1002/art.38078] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/03/2012] [Accepted: 06/27/2013] [Indexed: 11/08/2022]
Abstract
OBJECTIVE To delineate the constitutive pulmonary vascular phenotype of the TβRIIΔk-fib mouse model of scleroderma, and to selectively induce pulmonary endothelial cell injury using vascular endothelial growth factor (VEGF) inhibition to develop a model with features characteristic of pulmonary arterial hypertension (PAH). METHODS The TβRIIΔk-fib mouse strain expresses a kinase-deficient transforming growth factor β (TGFβ) receptor type II driven by a fibroblast-specific promoter, leading to ligand-dependent up-regulation of TGFβ signaling, and replicates key fibrotic features of scleroderma. Structural, biochemical, and functional assessments of pulmonary vessels, including in vivo hemodynamic studies, were performed before and following VEGF inhibition, which induced pulmonary endothelial cell apoptosis. These assessments included biochemical analysis of the TGFβ and VEGF signaling axes in tissue sections and explanted smooth muscle cells. RESULTS In the TβRIIΔk-fib mouse strain, a constitutive pulmonary vasculopathy with medial thickening, a perivascular proliferating chronic inflammatory cell infiltrate, and mildly elevated pulmonary artery pressure resembled the well-described chronic hypoxia model of pulmonary hypertension. Following administration of SU5416, the pulmonary vascular phenotype was more florid, with pulmonary arteriolar luminal obliteration by apoptosis-resistant proliferating endothelial cells. These changes resulted in right ventricular hypertrophy, confirming hemodynamically significant PAH. Altered expression of TGFβ and VEGF ligand and receptor was consistent with a scleroderma phenotype. CONCLUSION In this study, we replicated key features of systemic sclerosis-related PAH in a mouse model. Our results suggest that pulmonary endothelial cell injury in a genetically susceptible mouse strain triggers this complication and support the underlying role of functional interplay between TGFβ and VEGF, which provides insight into the pathogenesis of this disease.
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MESH Headings
- Angiogenesis Inhibitors/pharmacology
- Animals
- Disease Models, Animal
- Endothelium, Vascular/physiopathology
- Familial Primary Pulmonary Hypertension
- Female
- Hypertension, Pulmonary/etiology
- Hypertension, Pulmonary/genetics
- Hypertension, Pulmonary/physiopathology
- Hypoxia/genetics
- Hypoxia/physiopathology
- Indoles/pharmacology
- Lac Operon
- Male
- Mice
- Mice, Transgenic
- Phenotype
- Protein Serine-Threonine Kinases/genetics
- Protein Serine-Threonine Kinases/metabolism
- Pulmonary Circulation/physiology
- Pyrroles/pharmacology
- Receptor, Transforming Growth Factor-beta Type II
- Receptors, Transforming Growth Factor beta/genetics
- Receptors, Transforming Growth Factor beta/metabolism
- Receptors, Vascular Endothelial Growth Factor/antagonists & inhibitors
- Scleroderma, Systemic/complications
- Scleroderma, Systemic/genetics
- Scleroderma, Systemic/physiopathology
- Signal Transduction/physiology
- Transforming Growth Factor beta/metabolism
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Baliga RS, Milsom AB, Ghosh SM, Trinder SL, Macallister RJ, Ahluwalia A, Hobbs AJ. Dietary nitrate ameliorates pulmonary hypertension: cytoprotective role for endothelial nitric oxide synthase and xanthine oxidoreductase. Circulation 2012; 125:2922-32. [PMID: 22572914 DOI: 10.1161/circulationaha.112.100586] [Citation(s) in RCA: 92] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
BACKGROUND Pulmonary hypertension (PH) is a multifactorial disease characterized by increased pulmonary vascular resistance and right ventricular failure; morbidity and mortality remain unacceptably high. Loss of nitric oxide (NO) bioactivity is thought to contribute to the pathogenesis of PH, and agents that augment pulmonary NO signaling are clinically effective in the disease. Inorganic nitrate (NO(3)(-)) and nitrite (NO(2)(-)) elicit a reduction in systemic blood pressure in healthy individuals; this effect is underpinned by endogenous and sequential reduction to NO. Herein, we determined whether dietary nitrate and nitrite might be preferentially reduced to NO by the hypoxia associated with PH, and thereby offer a convenient, inexpensive method of supplementing NO functionality to reduce disease severity. METHODS AND RESULTS Dietary nitrate reduced the right ventricular pressure and hypertrophy, and pulmonary vascular remodeling in wild-type mice exposed to 3 weeks of hypoxia; this beneficial activity was mirrored largely by dietary nitrite. The cytoprotective effects of dietary nitrate were associated with increased plasma and lung concentrations of nitrite and cGMP. The beneficial effects of dietary nitrate and nitrite were reduced in mice lacking endothelial NO synthase or treated with the xanthine oxidoreductase inhibitor allopurinol. CONCLUSIONS These data demonstrate that dietary nitrate, and to a lesser extent dietary nitrite, elicit pulmonary dilatation, prevent pulmonary vascular remodeling, and reduce the right ventricular hypertrophy characteristic of PH. This favorable pharmacodynamic profile depends on endothelial NO synthase and xanthine oxidoreductase -catalyzed reduction of nitrite to NO. Exploitation of this mechanism (ie, dietary nitrate/nitrite supplementation) represents a viable, orally active therapy for PH.
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Affiliation(s)
- Reshma S Baliga
- William Harvey Research Institute, Queen Mary University of London, Charterhouse Square, London, EC1M 6BQ, United Kingdom.
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12
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Baliga RS, Trinder SL, Scotton CJ, Chambers RC, MacAllister RJ, Hobbs AJ. Enhancing natriuretic peptide bioactivity prevents bleomycin-induced pulmonary fibrosis. BMC Pharmacol 2011. [PMCID: PMC3363223 DOI: 10.1186/1471-2210-11-s1-p3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/02/2022] Open
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