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Evans AM, Mahmoud AD, Moral-Sanz J, Hartmann S. The emerging role of AMPK in the regulation of breathing and oxygen supply. Biochem J 2016; 473:2561-72. [PMID: 27574022 PMCID: PMC5003690 DOI: 10.1042/bcj20160002] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2016] [Revised: 04/20/2016] [Accepted: 05/03/2016] [Indexed: 01/25/2023]
Abstract
Regulation of breathing is critical to our capacity to accommodate deficits in oxygen availability and demand during, for example, sleep and ascent to altitude. It is generally accepted that a fall in arterial oxygen increases afferent discharge from the carotid bodies to the brainstem and thus delivers increased ventilatory drive, which restores oxygen supply and protects against hypoventilation and apnoea. However, the precise molecular mechanisms involved remain unclear. We recently identified as critical to this process the AMP-activated protein kinase (AMPK), which is key to the cell-autonomous regulation of metabolic homoeostasis. This observation is significant for many reasons, not least because recent studies suggest that the gene for the AMPK-α1 catalytic subunit has been subjected to natural selection in high-altitude populations. It would appear, therefore, that evolutionary pressures have led to AMPK being utilized to regulate oxygen delivery and thus energy supply to the body in the short, medium and longer term. Contrary to current consensus, however, our findings suggest that AMPK regulates ventilation at the level of the caudal brainstem, even when afferent input responses from the carotid body are normal. We therefore hypothesize that AMPK integrates local hypoxic stress at defined loci within the brainstem respiratory network with an index of peripheral hypoxic status, namely afferent chemosensory inputs. Allied to this, AMPK is critical to the control of hypoxic pulmonary vasoconstriction and thus ventilation-perfusion matching at the lungs and may also determine oxygen supply to the foetus by, for example, modulating utero-placental blood flow.
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Affiliation(s)
- A Mark Evans
- Centre for Integrative Physiology, College of Medicine and Veterinary Medicine, Hugh Robson Building, University of Edinburgh, Edinburgh EH8 9XD, U.K.
| | - Amira D Mahmoud
- Centre for Integrative Physiology, College of Medicine and Veterinary Medicine, Hugh Robson Building, University of Edinburgh, Edinburgh EH8 9XD, U.K
| | - Javier Moral-Sanz
- Centre for Integrative Physiology, College of Medicine and Veterinary Medicine, Hugh Robson Building, University of Edinburgh, Edinburgh EH8 9XD, U.K
| | - Sandy Hartmann
- Centre for Integrative Physiology, College of Medicine and Veterinary Medicine, Hugh Robson Building, University of Edinburgh, Edinburgh EH8 9XD, U.K
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102
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Chang WT, Weng SF, Hsu CH, Shih JY, Wang JJ, Wu CY, Chen ZC. Prognostic Factors in Patients With Pulmonary Hypertension-A Nationwide Cohort Study. J Am Heart Assoc 2016; 5:JAHA.116.003579. [PMID: 27572822 PMCID: PMC5079023 DOI: 10.1161/jaha.116.003579] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Background Pulmonary hypertension (PH) is a rare but fatal condition. Large‐scale studies to examine the prognostic factors are lacking. In the present study, we aimed to investigate the factors associated with overall mortality in PH patients. Methods and Results Based on Taiwan's National Health Insurance Database, we identified 1092 newly identified PH patients between 1999 and 2011. These patients were matched with 8736 healthy subjects based on propensity score calculated with age, sex, and chronic cardiovascular risk factors. Overall mortality, death incidence rate ratio, and hazard ratio were calculated. Patients with PH had a higher mortality than controls (56.45 versus 18.51 per 1000 person‐years, P<0.0001), with hazard ratio at 3.3 (95% CI: 2.92–3.73, P<0.001). The long‐term survival rates of the PH patients at 1, 5, and 10 years were 87.9%, 72.5%, and 62.6%, respectively, which were significantly lower than controls with 98.4%, 90.8%, and 83.6% at 1, 5, and 10 years, respectively. Among patients with PH, the mortality rate was higher in the older and male patients. However, after stratifying by age and sex, the younger (<50 years) and female patients had a higher risk. Regarding different etiologies of PH, chronic obstructive pulmonary disease and pulmonary embolism led to most cases of mortality (adjusted hazard ratio: 3.2, 95% CI: 2.76–3.71 and 4.64, 95% CI: 2.74–7.87, P<0.05). Conclusions PH has high mortality, especially in females, and patients with younger age and with chronic diseases. Chronic obstructive pulmonary disease and pulmonary embolism contributed to an increased risk of mortality in PH patients.
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Affiliation(s)
- Wei-Ting Chang
- Department of Cardiology, Chi Mei Medical Center, Tainan, Taiwan Department of Biotechnology, Southern Taiwan University of Science and Technology, Tainan 710, Taiwan
| | - Shih-Feng Weng
- Department of Healthcare Administration and Medical Informatics, Kaohsiung Medical University, Kaohsiung, Taiwan
| | - Chih-Hsin Hsu
- Department of Internal Medicine, Cheng Kung University Hospital, Tainan, Taiwan
| | - Jhih-Yuan Shih
- Department of Cardiology, Chi Mei Medical Center, Tainan, Taiwan
| | - Jhi-Joung Wang
- Department of Medical Research, Chi Mei Medical Center, Tainan, Taiwan
| | - Chun-Ying Wu
- Division of Gastroenterology, Taichung Veterans General Hospital, Taichung, Taiwan
| | - Zhih-Cherng Chen
- Department of Cardiology, Chi Mei Medical Center, Tainan, Taiwan Department of Pharmacy, Chia Nan University of Pharmacy and Science, Tainan City, Taiwan
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103
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Affiliation(s)
- Tim Lahm
- Division of Pulmonary, Critical Care, Occupational and Sleep Medicine; Department of Medicine, Indiana University School of Medicine, and Richard L. Roudebush VA Medical Center, Indianapolis, IN, USA
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104
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Moral-Sanz J, Mahmoud AD, Ross FA, Eldstrom J, Fedida D, Hardie DG, Evans AM. AMP-activated protein kinase inhibits Kv 1.5 channel currents of pulmonary arterial myocytes in response to hypoxia and inhibition of mitochondrial oxidative phosphorylation. J Physiol 2016; 594:4901-15. [PMID: 27062501 PMCID: PMC5009768 DOI: 10.1113/jp272032] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2015] [Accepted: 03/26/2016] [Indexed: 12/29/2022] Open
Abstract
Key points Progression of hypoxic pulmonary hypertension is thought to be due, in part, to suppression of voltage‐gated potassium channels (Kv) in pulmonary arterial smooth muscle by hypoxia, although the precise molecular mechanisms have been unclear. AMP‐activated protein kinase (AMPK) has been proposed to couple inhibition of mitochondrial metabolism by hypoxia to acute hypoxic pulmonary vasoconstriction and progression of pulmonary hypertension. Inhibition of complex I of the mitochondrial electron transport chain activated AMPK and inhibited Kv1.5 channels in pulmonary arterial myocytes. AMPK activation by 5‐aminoimidazole‐4‐carboxamide riboside, A769662 or C13 attenuated Kv1.5 currents in pulmonary arterial myocytes, and this effect was non‐additive with respect to Kv1.5 inhibition by hypoxia and mitochondrial poisons. Recombinant AMPK phosphorylated recombinant human Kv1.5 channels in cell‐free assays, and inhibited K+ currents when introduced into HEK 293 cells stably expressing Kv1.5. These results suggest that AMPK is the primary mediator of reductions in Kv1.5 channels following inhibition of mitochondrial oxidative phosphorylation during hypoxia and by mitochondrial poisons.
Abstract Progression of hypoxic pulmonary hypertension is thought to be due, in part, to suppression of voltage‐gated potassium channels (Kv) in pulmonary arterial smooth muscle cells that is mediated by the inhibition of mitochondrial oxidative phosphorylation. We sought to determine the role in this process of the AMP‐activated protein kinase (AMPK), which is intimately coupled to mitochondrial function due to its activation by LKB1‐dependent phosphorylation in response to increases in the cellular AMP:ATP and/or ADP:ATP ratios. Inhibition of complex I of the mitochondrial electron transport chain using phenformin activated AMPK and inhibited Kv currents in pulmonary arterial myocytes, consistent with previously reported effects of mitochondrial inhibitors. Myocyte Kv currents were also markedly inhibited upon AMPK activation by A769662, 5‐aminoimidazole‐4‐carboxamide riboside and C13 and by intracellular dialysis from a patch‐pipette of activated (thiophosphorylated) recombinant AMPK heterotrimers (α2β2γ1 or α1β1γ1). Hypoxia and inhibitors of mitochondrial oxidative phosphorylation reduced AMPK‐sensitive K+ currents, which were also blocked by the selective Kv1.5 channel inhibitor diphenyl phosphine oxide‐1 but unaffected by the presence of the BKCa channel blocker paxilline. Moreover, recombinant human Kv1.5 channels were phosphorylated by AMPK in cell‐free assays, and K+ currents carried by Kv1.5 stably expressed in HEK 293 cells were inhibited by intracellular dialysis of AMPK heterotrimers and by A769662, the effects of which were blocked by compound C. We conclude that AMPK mediates Kv channel inhibition by hypoxia in pulmonary arterial myocytes, at least in part, through phosphorylation of Kv1.5 and/or an associated protein. Progression of hypoxic pulmonary hypertension is thought to be due, in part, to suppression of voltage‐gated potassium channels (Kv) in pulmonary arterial smooth muscle by hypoxia, although the precise molecular mechanisms have been unclear. AMP‐activated protein kinase (AMPK) has been proposed to couple inhibition of mitochondrial metabolism by hypoxia to acute hypoxic pulmonary vasoconstriction and progression of pulmonary hypertension. Inhibition of complex I of the mitochondrial electron transport chain activated AMPK and inhibited Kv1.5 channels in pulmonary arterial myocytes. AMPK activation by 5‐aminoimidazole‐4‐carboxamide riboside, A769662 or C13 attenuated Kv1.5 currents in pulmonary arterial myocytes, and this effect was non‐additive with respect to Kv1.5 inhibition by hypoxia and mitochondrial poisons. Recombinant AMPK phosphorylated recombinant human Kv1.5 channels in cell‐free assays, and inhibited K+ currents when introduced into HEK 293 cells stably expressing Kv1.5. These results suggest that AMPK is the primary mediator of reductions in Kv1.5 channels following inhibition of mitochondrial oxidative phosphorylation during hypoxia and by mitochondrial poisons.
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Affiliation(s)
- Javier Moral-Sanz
- Centre for Integrative Physiology, College of Medicine and Veterinary Medicine, Hugh Robson Building, George Square, University of Edinburgh, Edinburgh, EH8 9XD, UK
| | - Amira D Mahmoud
- Centre for Integrative Physiology, College of Medicine and Veterinary Medicine, Hugh Robson Building, George Square, University of Edinburgh, Edinburgh, EH8 9XD, UK
| | - Fiona A Ross
- Division of Cell Signalling & Immunology, School of Life Sciences, University of Dundee, Dow Street, Dundee, DD1 5EH, UK
| | - Jodene Eldstrom
- Department of Anaesthesiology. Pharmacology and Therapeutics, University of British Columbia, 2350 Health Science Mall, Vancouver, Canada, V6T 1Z3
| | - David Fedida
- Department of Anaesthesiology. Pharmacology and Therapeutics, University of British Columbia, 2350 Health Science Mall, Vancouver, Canada, V6T 1Z3
| | - D Grahame Hardie
- Division of Cell Signalling & Immunology, School of Life Sciences, University of Dundee, Dow Street, Dundee, DD1 5EH, UK
| | - A Mark Evans
- Centre for Integrative Physiology, College of Medicine and Veterinary Medicine, Hugh Robson Building, George Square, University of Edinburgh, Edinburgh, EH8 9XD, UK
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105
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Lahm T, Frump AL, Albrecht ME, Fisher AJ, Cook TG, Jones TJ, Yakubov B, Whitson J, Fuchs RK, Liu A, Chesler NC, Brown MB. 17β-Estradiol mediates superior adaptation of right ventricular function to acute strenuous exercise in female rats with severe pulmonary hypertension. Am J Physiol Lung Cell Mol Physiol 2016; 311:L375-88. [PMID: 27288487 DOI: 10.1152/ajplung.00132.2016] [Citation(s) in RCA: 54] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2016] [Accepted: 06/08/2016] [Indexed: 12/12/2022] Open
Abstract
17β-Estradiol (E2) exerts protective effects on right ventricular (RV) function in pulmonary arterial hypertension (PAH). Since acute exercise-induced increases in afterload may lead to RV dysfunction in PAH, we sought to determine whether E2 allows for superior RV adaptation after an acute exercise challenge. We studied echocardiographic, hemodynamic, structural, and biochemical markers of RV function in male and female rats with sugen/hypoxia (SuHx)-induced pulmonary hypertension, as well as in ovariectomized (OVX) SuHx females, with or without concomitant E2 repletion (75 μg·kg(-1)·day(-1)) immediately after 45 min of treadmill running at 75% of individually determined maximal aerobic capacity (75% aerobic capacity reserve). Compared with males, intact female rats exhibited higher stroke volume and cardiac indexes, a strong trend for better RV compliance, and less pronounced increases in indexed total pulmonary resistance. OVX abrogated favorable RV adaptations, whereas E2 repletion after OVX markedly improved RV function. E2's effects on pulmonary vascular remodeling were complex and less robust than its RV effects. Postexercise hemodynamics in females with endogenous or exogenous E2 were similar to hemodynamics in nonexercised controls, whereas OVX rats exhibited more severely altered postexercise hemodynamics. E2 mediated inhibitory effects on RV fibrosis and attenuated increases in RV collagen I/III ratio. Proapoptotic signaling, endothelial nitric oxide synthase phosphorylation, and autophagic flux markers were affected by E2 depletion and/or repletion. Markers of impaired autophagic flux correlated with endpoints of RV structure and function. Endogenous and exogenous E2 exerts protective effects on RV function measured immediately after an acute exercise challenge. Harnessing E2's mechanisms may lead to novel RV-directed therapies.
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Affiliation(s)
- Tim Lahm
- Division of Pulmonary, Allergy, Critical Care, Occupational and Sleep Medicine, Department of Medicine, Indiana University School of Medicine, Indianapolis, Indiana; Department of Cellular and Integrative Physiology, Indiana University School of Medicine, Indianapolis, Indiana; Richard L. Roudebush Veterans Affairs Medical Center, Indianapolis, Indiana;
| | - Andrea L Frump
- Division of Pulmonary, Allergy, Critical Care, Occupational and Sleep Medicine, Department of Medicine, Indiana University School of Medicine, Indianapolis, Indiana
| | - Marjorie E Albrecht
- Division of Pulmonary, Allergy, Critical Care, Occupational and Sleep Medicine, Department of Medicine, Indiana University School of Medicine, Indianapolis, Indiana
| | - Amanda J Fisher
- Department of Anesthesiology, Indiana University School of Medicine, Indianapolis, Indiana
| | - Todd G Cook
- Indiana Center for Vascular Biology and Medicine, Indianapolis, Indiana
| | - Thomas J Jones
- Division of Pulmonary, Allergy, Critical Care, Occupational and Sleep Medicine, Department of Medicine, Indiana University School of Medicine, Indianapolis, Indiana
| | - Bakhtiyor Yakubov
- Division of Pulmonary, Allergy, Critical Care, Occupational and Sleep Medicine, Department of Medicine, Indiana University School of Medicine, Indianapolis, Indiana
| | - Jordan Whitson
- Division of Pulmonary, Allergy, Critical Care, Occupational and Sleep Medicine, Department of Medicine, Indiana University School of Medicine, Indianapolis, Indiana
| | - Robyn K Fuchs
- Department of Physical Therapy, Indiana University School of Health and Rehabilitation Sciences, Indianapolis, Indiana; and
| | - Aiping Liu
- Department of Biomedical Engineering, University of Wisconsin-Madison College of Engineering, Madison, Wisconsin
| | - Naomi C Chesler
- Department of Biomedical Engineering, University of Wisconsin-Madison College of Engineering, Madison, Wisconsin
| | - M Beth Brown
- Department of Physical Therapy, Indiana University School of Health and Rehabilitation Sciences, Indianapolis, Indiana; and
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106
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Stevens HC, Deng L, Grant JS, Pinel K, Thomas M, Morrell NW, MacLean MR, Baker AH, Denby L. Regulation and function of miR-214 in pulmonary arterial hypertension. Pulm Circ 2016; 6:109-17. [PMID: 27162619 PMCID: PMC4860547 DOI: 10.1086/685079] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
Dysregulation of microRNAs (miRNAs) can contribute to the etiology of diseases, including pulmonary arterial hypertension (PAH). Here we investigated a potential role for the miR-214 stem loop miRNA and the closely linked miR-199a miRNAs in PAH. All 4 miRNAs were upregulated in the lung and right ventricle (RV) in mice and rats exposed to the Sugen (SU) 5416 hypoxia model of PAH. Further, expression of the miRNAs was increased in pulmonary artery smooth muscle cells exposed to transforming growth factor β1 but not BMP4. We then examined miR-214(-/-) mice exposed to the SU 5416 hypoxia model of PAH or normoxic conditions and littermate controls. There were no changes in RV systolic pressure or remodeling observed between the miR-214(-/-) and wild-type hypoxic groups. However, we observed a significant increase in RV hypertrophy (RVH) in hypoxic miR-214(-/-) male mice compared with controls. Further, we identified that the validated miR-214 target phosphatase and tensin homolog was upregulated in miR-214(-/-) mice. Thus, miR-214 stem loop loss leads to elevated RVH and may contribute to the heart failure associated with PAH.
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Affiliation(s)
- Hannah C Stevens
- Institute of Cardiovascular and Medical Sciences, University of Glasgow, Glasgow, United Kingdom; Present affiliation: Queens Medical Research Institute, University of Edinburgh, Edinburgh
| | - Lin Deng
- Institute of Cardiovascular and Medical Sciences, University of Glasgow, Glasgow, United Kingdom; Present affiliation: Queens Medical Research Institute, University of Edinburgh, Edinburgh
| | - Jennifer S Grant
- Institute of Cardiovascular and Medical Sciences, University of Glasgow, Glasgow, United Kingdom; Present affiliation: Institute of Cellular Medicine, Newcastle University, Newcastle-upon-Tyne, United Kingdom
| | - Karine Pinel
- Institute of Cardiovascular and Medical Sciences, University of Glasgow, Glasgow, United Kingdom; Present affiliation: Queens Medical Research Institute, University of Edinburgh, Edinburgh
| | - Matthew Thomas
- Novartis Pharmaceuticals, Frimley Business Park, Frimley, Camberley, Surrey, United Kingdom; Present affiliations: AstraZeneca Research and Development and Göteborgs Universitet, Vastra Gotaland County, Sweden
| | - Nicholas W Morrell
- Division of Respiratory Medicine, Department of Medicine, Addenbrooke's Hospital, University of Cambridge School of Clinical Medicine, Cambridge, United Kingdom
| | - Margaret R MacLean
- Institute of Cardiovascular and Medical Sciences, University of Glasgow, Glasgow, United Kingdom
| | - Andrew H Baker
- Institute of Cardiovascular and Medical Sciences, University of Glasgow, Glasgow, United Kingdom; Present affiliation: Queens Medical Research Institute, University of Edinburgh, Edinburgh; These authors contributed equally to this work
| | - Laura Denby
- Institute of Cardiovascular and Medical Sciences, University of Glasgow, Glasgow, United Kingdom; Present affiliation: Queens Medical Research Institute, University of Edinburgh, Edinburgh; These authors contributed equally to this work
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107
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Abstract
In patients with pulmonary hypertension (PH), the primary cause of death is right ventricular (RV) failure. Improvement in RV function is therefore one of the most important treatment goals. In order to be able to reverse RV dysfunction and also prevent RV failure, a detailed understanding of the pathobiology of RV failure and the underlying mechanisms concerning the transition from a pressure-overloaded adapted right ventricle to a dilated and failing right ventricle is required. Here, we propose that insufficient RV contractility, myocardial fibrosis, capillary rarefaction, and a disturbed metabolism are important features of a failing right ventricle. Furthermore, an overview is provided about the potential direct RV effects of PH-targeted therapies and the effects of RV-directed medical treatments.
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Affiliation(s)
- Mariëlle C van de Veerdonk
- Department of Pulmonary Diseases, Institute for Cardiovascular Research (ICaR-VU), VU University Medical Center, Amsterdam, The Netherlands
| | - Harm J Bogaard
- Department of Pulmonary Diseases, Institute for Cardiovascular Research (ICaR-VU), VU University Medical Center, Amsterdam, The Netherlands
| | - Norbert F Voelkel
- The Victoria Johnson Pulmonary Research Laboratory, Virginia Commonwealth University, 1220 East Broad Street, Richmond, VA, 23298, USA.
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108
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109
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Ventetuolo CE, Mitra N, Wan F, Manichaikul A, Barr RG, Johnson C, Bluemke DA, Lima JAC, Tandri H, Ouyang P, Kawut SM. Oestradiol metabolism and androgen receptor genotypes are associated with right ventricular function. Eur Respir J 2015; 47:553-63. [PMID: 26647441 DOI: 10.1183/13993003.01083-2015] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2015] [Accepted: 10/09/2015] [Indexed: 11/05/2022]
Abstract
Sex hormones are linked to right ventricular (RV) function, but the relationship between genetic variation in these pathways and RV function is unknown.We performed a cross-sectional study of 2761 genotyped adults without cardiovascular disease. The relationships between RV measures and single nucleotide polymorphisms (SNPs) in 10 candidate genes were assessed. Urinary oestradiol (E2) metabolites produced by cytochrome P4501B1 (CYP1B1) and serum testosterone were measured in women and men respectively.In African-American (AA) women, the CYP1B1 SNP rs162561 was associated with RV ejection fraction (RVEF), such that each copy of the A allele was associated with a 2.0% increase in RVEF. Haplotype analysis revealed associations with RVEF in AA (global p<7.2×10(-6)) and white (global p=0.05) women. In white subjects, higher E2 metabolite levels were associated with significantly higher RVEF. In men, androgen receptors SNPs (rs1337080; rs5918764) were significantly associated with all RV measures and modified the relationship between testosterone and RVEF.Genetic variation in E2 metabolism and androgen signalling was associated with RV morphology in a sex-specific manner. The CYP1B1 SNP identified is in tight linkage disequilibrium with SNPs associated with pulmonary hypertension and oncogenesis, suggesting these pathways may underpin sexual dimorphism in RV failure.
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Affiliation(s)
- Corey E Ventetuolo
- Depts of Medicine and Health Services, Policy and Practice, Alpert Medical School of Brown University, Providence, RI, USA
| | - Nandita Mitra
- Dept of Biostatistics and Epidemiology, University of Pennsylvania, Philadelphia, PA, USA
| | - Fei Wan
- Dept of Biostatistics and Epidemiology, University of Pennsylvania, Philadelphia, PA, USA
| | - Ani Manichaikul
- Center for Public Health Genomics, Department of Public Health Sciences, University of Virginia, Charlottesville, VA, USA
| | - R Graham Barr
- Dept of Medicine, College of Physicians and Surgeons, Columbia University, New York, NY, USA
| | - Craig Johnson
- Dept of Biostatistics, University of Washington, Seattle, WA, USA
| | - David A Bluemke
- Radiology and Imaging Sciences, National Institutes of Health/Clinical Center, National Institute for Biomedical Imaging and Bioengineering, Bethesda, MD, USA
| | - Joao A C Lima
- Dept of Medicine, Johns Hopkins School of Medicine, Baltimore, MD, USA
| | - Hari Tandri
- Dept of Medicine, Johns Hopkins School of Medicine, Baltimore, MD, USA
| | - Pamela Ouyang
- Dept of Medicine, Johns Hopkins School of Medicine, Baltimore, MD, USA
| | - Steven M Kawut
- Dept of Biostatistics and Epidemiology, University of Pennsylvania, Philadelphia, PA, USA Dept of Medicine, University of Pennsylvania, Philadelphia, PA, USA Penn Cardiovascular Institute, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
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Kandhi S, Qin J, Froogh G, Jiang H, Luo M, Wolin MS, Huang A, Sun D. EET-dependent potentiation of pulmonary arterial pressure: sex-different regulation of soluble epoxide hydrolase. Am J Physiol Lung Cell Mol Physiol 2015; 309:L1478-86. [PMID: 26498250 DOI: 10.1152/ajplung.00208.2015] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2015] [Accepted: 10/17/2015] [Indexed: 01/24/2023] Open
Abstract
We tested the hypothesis that suppression of epoxyeicosatrienoic acid (EET) metabolism via genetic knockout of the gene for soluble epoxide hydrolase (sEH-KO), or female-specific downregulation of sEH expression, plays a role in the potentiation of pulmonary hypertension. We used male (M) and female (F) wild-type (WT) and sEH-KO mice; the latter have high pulmonary EETs. Right ventricular systolic pressure (RVSP) and mean arterial blood pressure (MABP) in control and in response to in vivo administration of U46619 (thromboxane analog), 14,15-EET, and 14,15-EEZE [14,15-epoxyeicosa-5(z)-enoic acid; antagonist of EETs] were recorded. Basal RVSP was comparable among all groups of mice, whereas MABP was significantly lower in F-WT than M-WT mice and further reduced predominantly in F-KO compared with M-KO mice. U46619 dose dependently increased RVSP and MABP in all groups of mice. The increase in RVSP was significantly greater and coincided with smaller increases in MABP in M-KO and F-WT mice compared with M-WT mice. In F-KO mice, the elevation of RVSP by U46619 was even higher than in M-KO and F-WT mice, associated with the least increase in MABP. 14,15-EEZE prevented the augmentation of U46619-induced elevation of RVSP in sEH-KO mice, whereas 14,15-EET-induced pulmonary vasoconstriction was comparable in all groups of mice. sEH expression in the lungs was reduced, paralleled with higher levels of EETs in F-WT compared with M-WT mice. In summary, EETs initiate pulmonary vasoconstriction but act as vasodilators systemically. High pulmonary EETs, as a function of downregulation or deletion of sEH, potentiate U46619-induced increases in RVSP in a female-susceptible manner.
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Affiliation(s)
- Sharath Kandhi
- Department of Physiology, New York Medical College, Valhalla, New York
| | - Jun Qin
- Department of Physiology, New York Medical College, Valhalla, New York; Department of Surgery, Renji Hospital, Shanghai Jiaotong University, School of Medicine, People's Republic of China; and
| | - Ghezal Froogh
- Department of Physiology, New York Medical College, Valhalla, New York
| | - Houli Jiang
- Department of Pharmacology, New York Medical College, Valhalla, New York
| | - Meng Luo
- Department of Surgery, Renji Hospital, Shanghai Jiaotong University, School of Medicine, People's Republic of China; and Shanghai 9th Hospital, Shanghai Jiaotong University, School of Medicine, People's Republic of China
| | - Michael S Wolin
- Department of Physiology, New York Medical College, Valhalla, New York
| | - An Huang
- Department of Physiology, New York Medical College, Valhalla, New York
| | - Dong Sun
- Department of Physiology, New York Medical College, Valhalla, New York;
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111
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Matalon S, Bartoszewski R, Collawn JF. Role of epithelial sodium channels in the regulation of lung fluid homeostasis. Am J Physiol Lung Cell Mol Physiol 2015; 309:L1229-38. [PMID: 26432872 DOI: 10.1152/ajplung.00319.2015] [Citation(s) in RCA: 94] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2015] [Accepted: 09/25/2015] [Indexed: 01/11/2023] Open
Abstract
In utero, fetal lung epithelial cells actively secrete Cl(-) ions into the lung air spaces while Na(+) ions follow passively to maintain electroneutrality. This process, driven by an electrochemical gradient generated by the Na(+)-K(+)-ATPase, is responsible for the secretion of fetal fluid that is essential for normal lung development. Shortly before birth, a significant upregulation of amiloride-sensitive epithelial channels (ENaCs) on the apical side of the lung epithelial cells results in upregulation of active Na(+) transport. This process is critical for the reabsorption of fetal lung fluid and the establishment of optimum gas exchange. In the adult lung, active Na(+) reabsorption across distal lung epithelial cells limits the degree of alveolar edema in patients with acute lung injury and cardiogenic edema. Cl(-) ions are transported either paracellularly or transcellularly to preserve electroneutrality. An increase in Cl(-) secretion across the distal lung epithelium has been reported following an acute increase in left atrial pressure and may result in pulmonary edema. In contrast, airway epithelial cells secrete Cl(-) through apical cystic fibrosis transmembrane conductance regulator and Ca(2+)-activated Cl(-) channels and absorb Na(+). Thus the coordinated action of Cl(-) secretion and Na(+) absorption is essential for maintenance of the volume of epithelial lining fluid that, in turn, maximizes mucociliary clearance and facilitates clearance of bacteria and debris from the lungs. Any factor that interferes with Na(+) or Cl(-) transport or dramatically upregulates ENaC activity in airway epithelial cells has been associated with lung diseases such as cystic fibrosis or chronic obstructive lung disease. In this review we focus on the role of the ENaC, the mechanisms involved in ENaC regulation, and how ENaC dysregulation can lead to lung pathology.
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Affiliation(s)
- Sadis Matalon
- Department of Anesthesiology and Perioperative Medicine, School of Medicine, University of Alabama at Birmingham, Birmingham, Alabama; Department of Cell, Developmental, and Integrative Biology, School of Medicine, University of Alabama at Birmingham, Birmingham, Alabama; Pulmonary Injury and Repair Center, School of Medicine, University of Alabama at Birmingham, Birmingham, Alabama; Gregory Fleming James Cystic Fibrosis Center, School of Medicine, University of Alabama at Birmingham, Birmingham, Alabama; and
| | - Rafal Bartoszewski
- Department of Biology and Pharmaceutical Botany, Medical University of Gdansk, Gdansk, Poland
| | - James F Collawn
- Department of Cell, Developmental, and Integrative Biology, School of Medicine, University of Alabama at Birmingham, Birmingham, Alabama; Pulmonary Injury and Repair Center, School of Medicine, University of Alabama at Birmingham, Birmingham, Alabama; Gregory Fleming James Cystic Fibrosis Center, School of Medicine, University of Alabama at Birmingham, Birmingham, Alabama; and
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112
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Sehgal PB, Yang YM, Miller EJ. Hypothesis: Neuroendocrine Mechanisms (Hypothalamus-Growth Hormone-STAT5 Axis) Contribute to Sex Bias in Pulmonary Hypertension. Mol Med 2015; 21:688-701. [PMID: 26252185 PMCID: PMC4749490 DOI: 10.2119/molmed.2015.00122] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2015] [Accepted: 07/30/2015] [Indexed: 12/12/2022] Open
Abstract
Pulmonary hypertension (PH) is a disease with high morbidity and mortality. The prevalence of idiopathic pulmonary arterial hypertension (IPAH) and hereditary pulmonary arterial hypertension (HPAH) is approximately two- to four-fold higher in women than in men. Paradoxically, there is an opposite male bias in typical rodent models of PH (chronic hypoxia or monocrotaline); in these models, administration of estrogenic compounds (for example, estradiol-17β [E2]) is protective. Further complexities are observed in humans ingesting anorexigens (female bias) and in rodent models, such as after hypoxia plus SU5416/Sugen (little sex bias) or involving serotonin transporter overexpression or dexfenfluramine administration (female bias). These complexities in sex bias in PH remain incompletely understood. We recently discovered that conditional deletion of signal transducer and activator of transcription 5a/b (STAT5a/b) in vascular smooth muscle cells abrogated the male bias in PH in hypoxic mice and that late-stage obliterative lesions in patients of both sexes with IPAH and HPAH showed reduced STAT5a/b, reduced Tyr-P-STAT5 and reduced B-cell lymphoma 6 protein (BCL6). In trying to understand the significance of these observations, we realized that there existed a well-characterized E2-sensitive central neuroendocrine mechanism of sex bias, studied over the last 40 years, that, at its peripheral end, culminated in species-specific male ("pulsatile") versus female ("more continuous") temporal patterns of circulating growth hormone (GH) levels leading to male versus female patterned activation of STAT5a/b in peripheral tissues and thus sex-biased expression of hundreds of genes. In this report, we consider the contribution of this neuroendocrine mechanism (hypothalamus-GH-STAT5) in the generation of sex bias in different PH situations.
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Affiliation(s)
- Pravin B Sehgal
- Department of Cell Biology and Anatomy, New York Medical College, Valhalla, New York, United States of America
- Department of Medicine, New York Medical College, Valhalla, New York, United States of America
| | - Yang-Ming Yang
- Department of Cell Biology and Anatomy, New York Medical College, Valhalla, New York, United States of America
| | - Edmund J Miller
- Center for Heart and Lung Research, The Feinstein Institute for Medical Research, Manhasset, New York, United States of America
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113
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Sehgal PB, Yang YM, Yuan H, Miller EJ. STAT5a/b contribute to sex bias in vascular disease: A neuroendocrine perspective. JAKSTAT 2015; 4:1-20. [PMID: 27141328 DOI: 10.1080/21623996.2015.1090658] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2015] [Revised: 08/25/2015] [Accepted: 08/27/2015] [Indexed: 12/24/2022] Open
Abstract
Previous studies have elucidated a neuroendocrine mechanism consisting of the hypothalamus (growth hormone releasing hormone, GHRH) - pituitary (growth hormone, GH) - STAT5a/b axis that underlies sex-biased gene expression in the liver. It is now established that male vs female patterned secretion of GHRH, and thus of circulating GH levels ("pulsatile" vs "more continuous" respectively), leading to differently patterned activation of PY-STAT5a/b in hepatocytes results in sex-biased gene expression of cohorts of hundreds of downstream genes. This review outlines new data in support of a STAT5a/b-based mechanism of sex bias in the vascular disease pulmonary hypertension (PH). Puzzling observations in PH include its 2-4-fold higher prevalence in women but a male-dominance in many rodent models, and, paradoxically, inhibition of PH development by estrogens in such models. We observed that conditional deletion of STAT5a/b in vascular smooth muscle cells (SMC) in mice converted the male-dominant model of chronic hypoxia-induced PH into a female-dominant phenotype. In human idiopathic PH, there was reduced STAT5a/b and PY-STAT5 in cells in late-stage obliterative pulmonary arterial lesions in both men and women. A juxtaposition of the prior liver data with the newer PH-related data drew attention to the hypothalamus-GH-STAT5 axis, which is the major target of estrogens at the level of the hypothalamus. This hypothesis explains many of the puzzling aspects of sex bias in PH in humans and rodent models. The extension of STAT5-anchored mechanisms of sex bias to vascular disease emphasizes the contribution of central neuroendocrine processes in generating sexual dimorphism in different tissues and cell types.
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Affiliation(s)
- Pravin B Sehgal
- Departments of Cell Biology & Anatomy; New York Medical College; Valhalla, NY USA; Department of Medicine; New York Medical College; Valhalla, NY USA
| | - Yang-Ming Yang
- Departments of Cell Biology & Anatomy; New York Medical College ; Valhalla, NY USA
| | - Huijuan Yuan
- Departments of Cell Biology & Anatomy; New York Medical College ; Valhalla, NY USA
| | - Edmund J Miller
- Center for Heart and Lung Research; The Feinstein Institute for Medical Research ; Manhasset, NY USA
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114
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Silva DMG, Nardiello C, Pozarska A, Morty RE. Recent advances in the mechanisms of lung alveolarization and the pathogenesis of bronchopulmonary dysplasia. Am J Physiol Lung Cell Mol Physiol 2015; 309:L1239-72. [PMID: 26361876 DOI: 10.1152/ajplung.00268.2015] [Citation(s) in RCA: 114] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2015] [Accepted: 09/09/2015] [Indexed: 02/08/2023] Open
Abstract
Alveolarization is the process by which the alveoli, the principal gas exchange units of the lung, are formed. Along with the maturation of the pulmonary vasculature, alveolarization is the objective of late lung development. The terminal airspaces that were formed during early lung development are divided by the process of secondary septation, progressively generating an increasing number of alveoli that are of smaller size, which substantially increases the surface area over which gas exchange can take place. Disturbances to alveolarization occur in bronchopulmonary dysplasia (BPD), which can be complicated by perturbations to the pulmonary vasculature that are associated with the development of pulmonary hypertension. Disturbances to lung development may also occur in persistent pulmonary hypertension of the newborn in term newborn infants, as well as in patients with congenital diaphragmatic hernia. These disturbances can lead to the formation of lungs with fewer and larger alveoli and a dysmorphic pulmonary vasculature. Consequently, affected lungs exhibit a reduced capacity for gas exchange, with important implications for morbidity and mortality in the immediate postnatal period and respiratory health consequences that may persist into adulthood. It is the objective of this Perspectives article to update the reader about recent developments in our understanding of the molecular mechanisms of alveolarization and the pathogenesis of BPD.
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Affiliation(s)
- Diogo M G Silva
- Department of Internal Medicine (Pulmonology), University of Giessen and Marburg Lung Center (UGMLC), Member of the German Center for Lung Research (DZL), Giessen, Germany; Department of Lung Development and Remodelling, Max Planck Institute for Heart and Lung Research, Bad Nauheim, Germany
| | - Claudio Nardiello
- Department of Internal Medicine (Pulmonology), University of Giessen and Marburg Lung Center (UGMLC), Member of the German Center for Lung Research (DZL), Giessen, Germany; Department of Lung Development and Remodelling, Max Planck Institute for Heart and Lung Research, Bad Nauheim, Germany
| | - Agnieszka Pozarska
- Department of Internal Medicine (Pulmonology), University of Giessen and Marburg Lung Center (UGMLC), Member of the German Center for Lung Research (DZL), Giessen, Germany; Department of Lung Development and Remodelling, Max Planck Institute for Heart and Lung Research, Bad Nauheim, Germany
| | - Rory E Morty
- Department of Internal Medicine (Pulmonology), University of Giessen and Marburg Lung Center (UGMLC), Member of the German Center for Lung Research (DZL), Giessen, Germany; Department of Lung Development and Remodelling, Max Planck Institute for Heart and Lung Research, Bad Nauheim, Germany
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115
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Swift AJ, Capener D, Hammerton C, Thomas SM, Elliot C, Condliffe R, Wild JM, Kiely DG. Right ventricular sex differences in patients with idiopathic pulmonary arterial hypertension characterised by magnetic resonance imaging: pair-matched case controlled study. PLoS One 2015; 10:e0127415. [PMID: 25996939 PMCID: PMC4440634 DOI: 10.1371/journal.pone.0127415] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2014] [Accepted: 04/14/2015] [Indexed: 11/25/2022] Open
Abstract
Purpose Sex differences exist in both the prevalence and survival of patients with idiopathic pulmonary arterial hypertension (IPAH). Men are less frequently affected by the condition but have worse outcome as compared to females. We sought to characterise the sex related differences in right ventricular remodelling in age matched male and female patients with IPAH using cardiac magnetic resonance imaging (MRI). Methods A case controlled pair-matched study was conducted with patients matched by age and sex. Steady state free precession (SSFP) MRI of the heart was performed at 1.5T. Cardiac volume, function and mass measurements were corrected for age, sex and BSA according to reference data. Results 40 age and sex matched patients with IPAH were identified. The mean age was 57 (SD 17) in both male and female cohorts. Men had proportionally lower right ventricular (RV) ejection fraction, RV stroke volume and LV stroke volume than females, p=0.028, p=0.007 and p=0.013, respectively. However, there was no significant difference in RV mass or haemodynamic indices of mPAP and PVR between males and females. Conclusion Male patients with IPAH have proportionally worse RV function despite similar afterload. We hypothesise that adaptive remodelling of the RV in response to increased afterload in IPAH is more effective in females.
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Affiliation(s)
- Andrew J. Swift
- Department of Cardiovascular Science, University of Sheffield, Sheffield, United Kingdom
- INSIGNEO, Institute for In Silico Medicine, University of Sheffield, Sheffield, United Kingdom
- * E-mail:
| | - Dave Capener
- Department of Cardiovascular Science, University of Sheffield, Sheffield, United Kingdom
| | - Charlotte Hammerton
- Department of Cardiovascular Science, University of Sheffield, Sheffield, United Kingdom
| | - Steven M. Thomas
- Radiology Department, Sheffield Teaching Hospitals NHS Foundation Trust, Sheffield, United Kingdom
| | - Charlie Elliot
- Sheffield Pulmonary Vascular Disease Unit, Royal Hallamshire Hospital, Sheffield Teaching Hospitals NHS Foundation Trust, Sheffield, United Kingdom
| | - Robin Condliffe
- Sheffield Pulmonary Vascular Disease Unit, Royal Hallamshire Hospital, Sheffield Teaching Hospitals NHS Foundation Trust, Sheffield, United Kingdom
| | - Jim M. Wild
- Department of Cardiovascular Science, University of Sheffield, Sheffield, United Kingdom
- INSIGNEO, Institute for In Silico Medicine, University of Sheffield, Sheffield, United Kingdom
| | - David G. Kiely
- INSIGNEO, Institute for In Silico Medicine, University of Sheffield, Sheffield, United Kingdom
- Sheffield Pulmonary Vascular Disease Unit, Royal Hallamshire Hospital, Sheffield Teaching Hospitals NHS Foundation Trust, Sheffield, United Kingdom
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116
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Kuijpers JM, van der Bom T, van Riel ACMJ, Meijboom FJ, van Dijk APJ, Pieper PG, Vliegen HW, Waskowsky WM, Oomen T, Zomer AC, Wagenaar LJ, Heesen WF, Roos-Hesselink JW, Zwinderman AH, Mulder BJM, Bouma BJ. Secundum atrial septal defect is associated with reduced survival in adult men. Eur Heart J 2015; 36:2079-2086. [DOI: 10.1093/eurheartj/ehv097] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/12/2014] [Accepted: 03/11/2015] [Indexed: 02/02/2023] Open
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Yang YM, Yuan H, Edwards JG, Skayian Y, Ochani K, Miller EJ, Sehgal PB. Deletion of STAT5a/b in vascular smooth muscle abrogates the male bias in hypoxic pulmonary hypertension in mice: implications in the human disease. Mol Med 2015; 20:625-38. [PMID: 25470773 DOI: 10.2119/molmed.2014.00180] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2014] [Accepted: 11/20/2014] [Indexed: 12/27/2022] Open
Abstract
Chronic hypoxia typically elicits pulmonary hypertension (PH) in mice with a male-dominant phenotype. There is an opposite-sex bias in human PH, with a higher prevalence in women, but greater survival (the "estrogen paradox"). We investigated the involvement of the STAT5a/b species, previously established to mediate sexual dimorphism in other contexts, in the sex bias in PH. Mice with heterozygous or homozygous deletions of the STAT5a/b locus in vascular smooth muscle cells (SMCs) were generated in crosses between STAT5a/b(fl/fl) and transgelin (SM22α)-Cre(+/+) parents. Wild-type (wt) males subjected to chronic hypoxia showed significant PH and pulmonary arterial remodeling, with wt females showing minimal changes (a male-dominant phenotype). However, in conditional STAT5(+/-) or STAT5(-/-) mice, hypoxic females showed the severest manifestations of PH (a female-dominant phenotype). Immunofluorescence studies on human lung sections showed that obliterative pulmonary arterial lesions in patients with idiopathic pulmonary arterial hypertension (IPAH) or hereditary pulmonary arterial hypertension (HPAH), both male and female, overall had reduced STAT5a/b, reduced PY-STAT5 and reduced endoplasmic reticulum (ER) GTPase atlastin-3 (ATL3). Studies of SMCs and endothelial cell (EC) lines derived from vessels isolated from lungs of male and female IPAH patients and controls revealed instances of coordinate reductions in STAT5a, STAT5b and ATL3 in IPAH-derived cells, including SMCs and ECs from the same patient. Taken together, these data provide the first definitive evidence for a contribution of STAT5a/b to the sex bias in PH in the hypoxic mouse and implicate reduced STAT5 in the pathogenesis of the human disease.
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Affiliation(s)
- Yang-Ming Yang
- Department of Cell Biology & Anatomy, New York Medical College, Valhalla, New York, United States of America
| | - Huijuan Yuan
- Department of Cell Biology & Anatomy, New York Medical College, Valhalla, New York, United States of America
| | - John G Edwards
- Department of Physiology, New York Medical College, Valhalla, New York, United States of America
| | - Yester Skayian
- Department of Physiology, New York Medical College, Valhalla, New York, United States of America
| | - Kanta Ochani
- Center for Heart and Lung Research, The Feinstein Institute for Medical Research, Manhasset, New York, United States of America
| | - Edmund J Miller
- Center for Heart and Lung Research, The Feinstein Institute for Medical Research, Manhasset, New York, United States of America
| | - Pravin B Sehgal
- Department of Cell Biology & Anatomy, New York Medical College, Valhalla, New York, United States of America.,Department of Medicine, New York Medical College, Valhalla, New York, United States of America
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Frump AL, Goss KN, Vayl A, Albrecht M, Fisher A, Tursunova R, Fierst J, Whitson J, Cucci AR, Brown MB, Lahm T. Estradiol improves right ventricular function in rats with severe angioproliferative pulmonary hypertension: effects of endogenous and exogenous sex hormones. Am J Physiol Lung Cell Mol Physiol 2015; 308:L873-90. [PMID: 25713318 DOI: 10.1152/ajplung.00006.2015] [Citation(s) in RCA: 106] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2015] [Accepted: 02/18/2015] [Indexed: 12/22/2022] Open
Abstract
Estrogens are disease modifiers in PAH. Even though female patients exhibit better right ventricular (RV) function than men, estrogen effects on RV function (a major determinant of survival in PAH) are incompletely characterized. We sought to determine whether sex differences exist in RV function in the SuHx model of PAH, whether hormone depletion in females worsens RV function, and whether E2 repletion improves RV adaptation. Furthermore, we studied the contribution of ERs in mediating E2's RV effects. SuHx-induced pulmonary hypertension (SuHx-PH) was induced in male and female Sprague-Dawley rats as well as OVX females with or without concomitant E2 repletion (75 μg·kg(-1)·day(-1)). Female SuHx rats exhibited superior CI than SuHx males. OVX worsened SuHx-induced decreases in CI and SuHx-induced increases in RVH and inflammation (MCP-1 and IL-6). E2 repletion in OVX rats attenuated SuHx-induced increases in RV systolic pressure (RVSP), RVH, and pulmonary artery remodeling and improved CI and exercise capacity (V̇o2max). Furthermore, E2 repletion ameliorated SuHx-induced alterations in RV glutathione activation, proapoptotic signaling, cytoplasmic glycolysis, and proinflammatory cytokine expression. Expression of ERα in RV was decreased in SuHx-OVX but was restored upon E2 repletion. RV ERα expression was inversely correlated with RVSP and RVH and positively correlated with CO and apelin RNA levels. RV-protective E2 effects observed in females were recapitulated in male SuHx rats treated with E2 or with pharmacological ERα or ERβ agonists. Our data suggest significant RV-protective ER-mediated effects of E2 in a model of severe PH.
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Affiliation(s)
- Andrea L Frump
- Division of Pulmonary, Allergy, Critical Care, Occupational and Sleep Medicine; Department of Medicine, Indiana University School of Medicine, Indianapolis, Indiana
| | - Kara N Goss
- Division of Pulmonary, Allergy, Critical Care, Occupational and Sleep Medicine; Department of Medicine, Indiana University School of Medicine, Indianapolis, Indiana
| | - Alexandra Vayl
- Division of Pulmonary, Allergy, Critical Care, Occupational and Sleep Medicine; Department of Medicine, Indiana University School of Medicine, Indianapolis, Indiana
| | - Marjorie Albrecht
- Division of Pulmonary, Allergy, Critical Care, Occupational and Sleep Medicine; Department of Medicine, Indiana University School of Medicine, Indianapolis, Indiana
| | - Amanda Fisher
- Department of Anesthesiology, Indiana University School of Medicine, Indianapolis, Indiana
| | - Roziya Tursunova
- Division of Pulmonary, Allergy, Critical Care, Occupational and Sleep Medicine; Department of Medicine, Indiana University School of Medicine, Indianapolis, Indiana
| | - John Fierst
- Division of Pulmonary, Allergy, Critical Care, Occupational and Sleep Medicine; Department of Medicine, Indiana University School of Medicine, Indianapolis, Indiana
| | - Jordan Whitson
- Division of Pulmonary, Allergy, Critical Care, Occupational and Sleep Medicine; Department of Medicine, Indiana University School of Medicine, Indianapolis, Indiana
| | - Anthony R Cucci
- Division of Pulmonary, Allergy, Critical Care, Occupational and Sleep Medicine; Department of Medicine, Indiana University School of Medicine, Indianapolis, Indiana
| | - M Beth Brown
- Department of Physical Therapy, Indiana University School of Health and Rehabilitation Sciences
| | - Tim Lahm
- Division of Pulmonary, Allergy, Critical Care, Occupational and Sleep Medicine; Department of Medicine, Indiana University School of Medicine, Indianapolis, Indiana; Center for Immunobiology, Indiana University School of Medicine, Indianapolis, Indiana; and Richard L. Roudebush VA Medical Center, Indianapolis, Indiana
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