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Neira F, Neira N, Torres J, González-Ortiz M. Physiological and Pathophysiological Role of Large-Conductance Calcium-Activated Potassium Channels (BKCa) in HUVECs and Placenta. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2023; 1428:71-82. [PMID: 37466769 DOI: 10.1007/978-3-031-32554-0_3] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/20/2023]
Abstract
BKCa channels (large-conductance Ca2+-activated K+ channels) play a critical role in regulating vascular tone and blood pressure. These channels are present in the smooth muscle cells of blood vessels and are activated by voltage and increased intracellular Ca2+ concentration. More recently, the expression and activity of BKCa have been proposed to be relevant in endothelial cells, too, specifically in human umbilical vein endothelial cells (HUVECs), the more studied cell type in the fetoplacental circulation. The role of BKCa in endothelial cells is not well understood, but in HUVECs or placental endothelium, these channels could be crucial for vascular tone regulation during pregnancy as part of endothelium-derived hyperpolarization (EDH), a key mechanism for an organ that lacks nervous system innervation like the placenta.In this review, we will discuss the evidence about the role of BKCa (and other Ca2+-activated K+ channels) in HUVECs and the placenta to propose a physiological mechanism for fetoplacental vascular regulation and a pathophysiological role of BKCa, mainly associated with pregnancy pathologies that present maternal hypertension and/or placental hypoxia, like preeclampsia.
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Affiliation(s)
- Fernanda Neira
- Laboratorio de Investigación Materno-Fetal (LIMaF), Departamento de Obstetricia y Ginecología, Facultad de Medicina, Universidad de Concepción, Concepción, Chile
| | - Nataly Neira
- Laboratorio de Investigación Materno-Fetal (LIMaF), Departamento de Obstetricia y Ginecología, Facultad de Medicina, Universidad de Concepción, Concepción, Chile
| | - Javier Torres
- Laboratorio de Investigación Materno-Fetal (LIMaF), Departamento de Obstetricia y Ginecología, Facultad de Medicina, Universidad de Concepción, Concepción, Chile
| | - Marcelo González-Ortiz
- Laboratorio de Investigación Materno-Fetal (LIMaF), Departamento de Obstetricia y Ginecología, Facultad de Medicina, Universidad de Concepción, Concepción, Chile.
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Krause BJ. Novel insights for the role of nitric oxide in placental vascular function during and beyond pregnancy. J Cell Physiol 2021; 236:7984-7999. [PMID: 34121195 DOI: 10.1002/jcp.30470] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2020] [Revised: 05/28/2021] [Accepted: 06/01/2021] [Indexed: 01/02/2023]
Abstract
More than 30 years have passed since endothelial nitric oxide synthesis was described using the umbilical artery and vein endothelium. That seminal report set the cornerstone for unveiling the molecular aspects of endothelial function. In parallel, the understanding of placental physiology has gained growing interest, due to its crucial role in intrauterine development, with considerable long-term health consequences. This review discusses the evidence for nitric oxide (NO) as a critical player of placental development and function, with a special focus on endothelial nitric oxide synthase (eNOS) vascular effects. Also, the regulation of eNOS-dependent vascular responses in normal pregnancy and pregnancy-related diseases and their impact on prenatal and postnatal vascular health are discussed. Recent and compelling evidence has reinforced that eNOS regulation results from a complex network of processes, with novel data concerning mechanisms such as mechano-sensing, epigenetic, posttranslational modifications, and the expression of NO- and l-arginine-related pathways. In this regard, most of these mechanisms are expressed in an arterial-venous-specific manner and reflect traits of the fetal systemic circulation. Several studies using umbilical endothelial cells are not aimed to understand placental function but general endothelial function, reinforcing the influence of the placenta on general knowledge in physiology.
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Affiliation(s)
- Bernardo J Krause
- Instituto de Ciencias de la Salud, Universidad de O'Higgins, Rancagua, Chile
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Impairment of BKca channels in human placental chorionic plate arteries is potentially relevant to the development of preeclampsia. Hypertens Res 2017; 41:126-134. [DOI: 10.1038/hr.2017.99] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2017] [Revised: 06/05/2017] [Accepted: 07/18/2017] [Indexed: 01/02/2023]
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Zaborska KE, Wareing M, Austin C. Comparisons between perivascular adipose tissue and the endothelium in their modulation of vascular tone. Br J Pharmacol 2017; 174:3388-3397. [PMID: 27747871 PMCID: PMC5610163 DOI: 10.1111/bph.13648] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2016] [Revised: 09/16/2016] [Accepted: 09/28/2016] [Indexed: 01/06/2023] Open
Abstract
The endothelium is an established modulator of vascular tone; however, the recent discovery of the anti-contractile nature of perivascular adipose tissue (PVAT) suggests that the fat, which surrounds many blood vessels, can also modulate vascular tone. Both the endothelium and PVAT secrete vasoactive substances, which regulate vascular function. Many of these factors are common to both the endothelium and PVAT; therefore, this review will highlight the potential shared mechanisms in the modulation of vascular tone. Endothelial dysfunction is a hallmark of many vascular diseases, including hypertension and obesity. Moreover, PVAT dysfunction is now being reported in several cardio-metabolic disorders. Thus, this review will also discuss the mechanistic insights into endothelial and PVAT dysfunction in order to evaluate whether PVAT modulation of vascular contractility is similar to that of the endothelium in health and disease. LINKED ARTICLES This article is part of a themed section on Molecular Mechanisms Regulating Perivascular Adipose Tissue - Potential Pharmacological Targets? To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v174.20/issuetoc.
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Affiliation(s)
- K E Zaborska
- Institute of Cardiovascular SciencesUniversity of ManchesterUK
| | - M Wareing
- Maternal and Fetal Health Research Centre, Institute of Human DevelopmentUniversity of ManchesterUK
| | - C Austin
- Faculty of Health and Social CareEdge Hill UniversityUK
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Li FF, He MZ, Xie Y, Wu YY, Yang MT, Fan Y, Qiao FY, Deng DR. Involvement of dysregulated IK Ca and SK Ca channels in preeclampsia. Placenta 2017; 58:9-16. [PMID: 28962702 DOI: 10.1016/j.placenta.2017.07.361] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/23/2017] [Revised: 07/25/2017] [Accepted: 07/31/2017] [Indexed: 01/08/2023]
Abstract
INTRODUCTION Excessive constriction of placental chorionic plate arteries (CPAs) may be associated with preeclampsia (PE). Nitric oxide (NO) as well as intermediate and small Ca2+-activated K+ channels (IKCa and SKCa) plays vital roles in vasodilation of CPAs. We hypothesized that dysregulated IKCa and SKCa channels may be involved in the pathogenesis of PE mediated by the impaired NO system on CPAs. METHODS The location of IKCa and SKCa channels, activities of NO synthases (NOS), and expression levels of these molecules were studied on CPAs from 30 normal pregnancies and 30 PE. The vasodilating function of CPAs was measured under openers or blockers of IKCa/SKCa channels in the presence or absence of NO donor or inhibitor. RESULTS IKCa and SKCa channels were located both on endothelium and on smooth muscles of CPAs and the expressions of them were downregulated in PE women comparing to those in normal pregnant women. The protein expressions of endothelial NOS (eNOS) and inducible NOS (iNOS) were downregulated on CPAs in PE accompanied by decreased activity of eNOS. Notably, the vasodilatory functions mediated by IKCa/SKCa channels and by NO were aberrant on preeclamptic CPAs. In addition, IKCa and SKCa channels were responsible for nitric oxide (NO)-attributable vasorelaxation and activity modulation of NO synthases. CONCLUSIONS This study provides evidence that dysregulated IKCa and SKCa channels might contribute to fetal pathogenesis of PE through direct promotion of vascular constriction of CPAs and through affecting functions of NO and activities of NOS.
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Affiliation(s)
- Fan-Fan Li
- Department of Gynecology and Obstetrics, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China
| | - Meng-Zhou He
- Department of Gynecology and Obstetrics, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China
| | - Yin Xie
- Department of Gynecology and Obstetrics, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China
| | - Yuan-Yuan Wu
- Department of Gynecology and Obstetrics, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China
| | - Mei-Tao Yang
- Department of Gynecology and Obstetrics, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China
| | - Yao Fan
- Department of Gynecology and Obstetrics, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China
| | - Fu-Yuan Qiao
- Department of Gynecology and Obstetrics, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China
| | - Dong-Rui Deng
- Department of Gynecology and Obstetrics, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China.
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Cabrera L, Saavedra A, Rojas S, Cid M, Valenzuela C, Gallegos D, Careaga P, Basualto E, Haensgen A, Peña E, Rivas C, Vera JC, Gallardo V, Zúñiga L, Escudero C, Sobrevia L, Wareing M, González M. Insulin Induces Relaxation and Decreases Hydrogen Peroxide-Induced Vasoconstriction in Human Placental Vascular Bed in a Mechanism Mediated by Calcium-Activated Potassium Channels and L-Arginine/Nitric Oxide Pathways. Front Physiol 2016; 7:529. [PMID: 27920724 PMCID: PMC5118463 DOI: 10.3389/fphys.2016.00529] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2016] [Accepted: 10/25/2016] [Indexed: 01/04/2023] Open
Abstract
HIGHLIGHTSShort-term incubation with insulin increases the L-arginine transport in HUVECs. Short-term incubation with insulin increases the NO synthesis in HUVECs. Insulin induces relaxation in human placental vascular bed. Insulin attenuates the constriction induced by hydrogen peroxide in human placenta. The relaxation induced by insulin is dependent on BKCa channels activity in human placenta.
Insulin induces relaxation in umbilical veins, increasing the expression of human amino acid transporter 1 (hCAT-1) and nitric oxide synthesis (NO) in human umbilical vein endothelial cells (HUVECs). Short-term effects of insulin on vasculature have been reported in healthy subjects and cell cultures; however, its mechanisms remain unknown. The aim of this study was to characterize the effect of acute incubation with insulin on the regulation of vascular tone of placental vasculature. HUVECs and chorionic vein rings were isolated from normal pregnancies. The effect of insulin on NO synthesis, L-arginine transport, and hCAT-1 abundance was measured in HUVECs. Isometric tension induced by U46619 (thromboxane A2 analog) or hydrogen peroxide (H2O2) were measured in vessels previously incubated 30 min with insulin and/or the following pharmacological inhibitors: tetraethylammonium (KCa channels), iberiotoxin (BKCa channels), genistein (tyrosine kinases), and wortmannin (phosphatidylinositol 3-kinase). Insulin increases L-arginine transport and NO synthesis in HUVECs. In the placenta, this hormone caused relaxation of the chorionic vein, and reduced perfusion pressure in placental cotyledons. In vessels pre-incubated with insulin, the constriction evoked by H2O2 and U46619 was attenuated and the effect on H2O2-induced constriction was blocked with tetraethylammonium and iberiotoxin, but not with genistein, or wortmannin. Insulin rapidly dilates the placental vasculature through a mechanism involving activity of BKCa channels and L-arginine/NO pathway in endothelial cells. This phenomenon is related to quick increases of hCAT-1 abundance and higher capacity of endothelial cells to take up L-arginine and generate NO.
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Affiliation(s)
- Lissette Cabrera
- Vascular Physiology Laboratory, Department of Physiology, Faculty of Biological Sciences, Universidad de ConcepciónConcepción, Chile; Department of Morphophysiology, Faculty of Medicine, Universidad Diego PortalesSantiago, Chile
| | - Andrea Saavedra
- Vascular Physiology Laboratory, Department of Physiology, Faculty of Biological Sciences, Universidad de Concepción Concepción, Chile
| | - Susana Rojas
- Vascular Physiology Laboratory, Department of Physiology, Faculty of Biological Sciences, Universidad de Concepción Concepción, Chile
| | - Marcela Cid
- Department of Obstetrics and Childcare, Faculty of Medicine, Universidad de Concepción Concepción, Chile
| | - Cristina Valenzuela
- Vascular Physiology Laboratory, Department of Physiology, Faculty of Biological Sciences, Universidad de Concepción Concepción, Chile
| | - David Gallegos
- Vascular Physiology Laboratory, Department of Physiology, Faculty of Biological Sciences, Universidad de Concepción Concepción, Chile
| | - Pamela Careaga
- Vascular Physiology Laboratory, Department of Physiology, Faculty of Biological Sciences, Universidad de Concepción Concepción, Chile
| | - Emerita Basualto
- Vascular Physiology Laboratory, Department of Physiology, Faculty of Biological Sciences, Universidad de Concepción Concepción, Chile
| | - Astrid Haensgen
- Vascular Physiology Laboratory, Department of Physiology, Faculty of Biological Sciences, Universidad de Concepción Concepción, Chile
| | - Eduardo Peña
- Department of Pathophysiology, Faculty of Biological Sciences, Universidad de Concepción Concepción, Chile
| | - Coralia Rivas
- Department of Pathophysiology, Faculty of Biological Sciences, Universidad de Concepción Concepción, Chile
| | - Juan Carlos Vera
- Department of Pathophysiology, Faculty of Biological Sciences, Universidad de Concepción Concepción, Chile
| | - Victoria Gallardo
- Department of Pathophysiology, Faculty of Biological Sciences, Universidad de ConcepciónConcepción, Chile; Group of Research and Innovation in Vascular Health (GRIVAS Health)Chillán, Chile
| | - Leandro Zúñiga
- Centro de Investigaciones Médicas (CIM), School of Medicine, Universidad de Talca Talca, Chile
| | - Carlos Escudero
- Group of Research and Innovation in Vascular Health (GRIVAS Health)Chillán, Chile; Vascular Physiology Laboratory, Group of Investigation in Tumor Angiogenesis (GIANT), Department of Basic Sciences, Universidad del BiobíoChillán, Chile
| | - Luis Sobrevia
- Cellular and Molecular Physiology Laboratory (CMPL), Division of Obstetrics and Gynecology, School of Medicine, Faculty of Medicine, Pontificia Universidad Católica de ChileSantiago, Chile; Department of Physiology, Faculty of Pharmacy, Universidad de SevillaSeville, Spain; University of Queensland Centre for Clinical Research (UQCCR), Faculty of Medicine and Biomedical Sciences, University of QueenslandHerston, QLD, Australia
| | - Mark Wareing
- Maternal and Fetal Health Research Centre, Institute of Human Development, University of ManchesterManchester, UK; Maternal and Fetal Health Research Centre, St. Mary's Hospital, Central Manchester University Hospitals NHS Foundation Trust, Manchester Academic Health Science CentreManchester, UK
| | - Marcelo González
- Vascular Physiology Laboratory, Department of Physiology, Faculty of Biological Sciences, Universidad de ConcepciónConcepción, Chile; Group of Research and Innovation in Vascular Health (GRIVAS Health)Chillán, Chile
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Broegger T, Andersson KE, Aalkjaer C, Forman A, Boedtkjer DB. Sensitivity to the thromboxane A 2 analog U46619 varies with inner diameter in human stem villous arteries. Placenta 2016; 39:111-5. [DOI: 10.1016/j.placenta.2016.01.017] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/27/2015] [Revised: 01/18/2016] [Accepted: 01/20/2016] [Indexed: 11/29/2022]
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Ali TY, Broughton Pipkin F, Khan RN. The effect of pH and ion channel modulators on human placental arteries. PLoS One 2014; 9:e114405. [PMID: 25490401 PMCID: PMC4260857 DOI: 10.1371/journal.pone.0114405] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2014] [Accepted: 11/06/2014] [Indexed: 12/31/2022] Open
Abstract
Chorionic plate arteries (CPA) are located at the maternofetal interface where they are able to respond to local metabolic changes. Unlike many other types of vasculature, the placenta lacks nervous control and requires autoregulation for controlling blood flow. The placental circulation, which is of low-resistance, may become hypoxic easily leading to fetal acidosis and fetal distress however the role of the ion channels in these circumstances is not well-understood. Active potassium channel conductances that are subject to local physicochemical modulation may serve as pathways through which such signals are transduced. The aim of this study was to investigate the modulation of CPA by pH and the channels implicated in these responses using wire myography. CPA were isolated from healthy placentae and pre-contracted with U46619 before testing the effects of extracellular pH using 1 M lactic acid over the pH range 7.4 - 6.4 in the presence of a variety of ion channel modulators. A change from pH 7.4 to 7.2 produced a 29±3% (n = 9) relaxation of CPA which increased to 61±4% at the lowest pH of 6.4. In vessels isolated from placentae of women with pre-eclampsia (n = 6), pH responses were attenuated. L-methionine increased the relaxation to 67±7% (n = 6; p<0.001) at pH 6.4. Similarly the TASK 1/3 blocker zinc chloride (1 mM) gave a maximum relaxation of 72±5% (n = 8; p<0.01) which compared with the relaxation produced by the TREK-1 opener riluzole (75±5%; n = 6). Several other modulators induced no significant changes in vascular responses. Our study confirmed expression of several ion channel subtypes in CPA with our results indicating that extracellular pH within the physiological range has an important role in controlling vasodilatation in the human term placenta.
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Affiliation(s)
- Tayyba Y Ali
- Division of Medical Sciences & Graduate Entry Medicine, School of Medicine, University of Nottingham, Royal Derby Hospital Centre, Uttoxeter Road, Derby DE22 3DT, United Kingdom
| | - Fiona Broughton Pipkin
- Division of Medical Sciences & Graduate Entry Medicine, School of Medicine, University of Nottingham, Royal Derby Hospital Centre, Uttoxeter Road, Derby DE22 3DT, United Kingdom
| | - Raheela N Khan
- Division of Medical Sciences & Graduate Entry Medicine, School of Medicine, University of Nottingham, Royal Derby Hospital Centre, Uttoxeter Road, Derby DE22 3DT, United Kingdom
- * E-mail:
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Sánchez-Aranguren LC, Prada CE, Riaño-Medina CE, Lopez M. Endothelial dysfunction and preeclampsia: role of oxidative stress. Front Physiol 2014; 5:372. [PMID: 25346691 PMCID: PMC4193194 DOI: 10.3389/fphys.2014.00372] [Citation(s) in RCA: 255] [Impact Index Per Article: 25.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2014] [Accepted: 09/09/2014] [Indexed: 01/22/2023] Open
Abstract
Preeclampsia (PE) is an often fatal pathology characterized by hypertension and proteinuria at the 20th week of gestation that affects 5-10% of the pregnancies. The problem is particularly important in developing countries in where the incidence of hypertensive disorders of pregnancy is higher and maternal mortality rates are 20 times higher than those reported in developed countries. Risk factors for the development of PE include obesity, insulin resistance and hyperlipidemia that stimulate inflammatory cytokine release and oxidative stress leading to endothelial dysfunction (ED). However, how all these clinical manifestations concur to develop PE is still not very well understood. The related poor trophoblast invasion and uteroplacental artery remodeling described in PE, increases reactive oxygen species (ROS), hypoxia and ED. Here we aim to review current literature from research showing the interplay between oxidative stress, ED and PE to the outcomes of current clinical trials aiming to prevent PE with antioxidant supplementation.
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Affiliation(s)
- Lissette C. Sánchez-Aranguren
- Translational Biomedical Research Group, Biotechnology, Innovation and Technology Development, Cardiovascular Foundation of ColombiaFloridablanca, Colombia
- Graduate Program in Biomedical Sciences, Faculty of Health, Universidad del ValleCali, Colombia
| | - Carlos E. Prada
- Translational Biomedical Research Group, Biotechnology, Innovation and Technology Development, Cardiovascular Foundation of ColombiaFloridablanca, Colombia
- Center for Genomic Medicine and Metabolism, Instituto del Corazón de Floridablanca, Cardiovascular Foundation of ColombiaFloridablanca, Colombia
- Division of Human Genetics, Cincinnati Children's Hospital Medical Center, University of Cincinnati College of MedicineCincinnati, OH, USA
| | - Carlos E. Riaño-Medina
- Translational Biomedical Research Group, Biotechnology, Innovation and Technology Development, Cardiovascular Foundation of ColombiaFloridablanca, Colombia
- Maternal-Fetal Medicine Program, Cardiovascular Foundation of ColombiaFloridablanca, Colombia
| | - Marcos Lopez
- Translational Biomedical Research Group, Biotechnology, Innovation and Technology Development, Cardiovascular Foundation of ColombiaFloridablanca, Colombia
- Graduate Program in Biomedical Sciences, Faculty of Health, Universidad del ValleCali, Colombia
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Wareing M. Oxygen sensitivity, potassium channels, and regulation of placental vascular tone. Microcirculation 2014; 21:58-66. [PMID: 23710683 DOI: 10.1111/micc.12069] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2013] [Accepted: 05/21/2013] [Indexed: 12/17/2022]
Abstract
The human fetoplacental vasculature is a low-resistance circulation with deoxygenated arterial relative to venous blood. The placenta lacks neuronal innervation suggesting that local physical (e.g., oxygenation; flow rate), paracrine (e.g., endothelial cell nitric oxide), and circulating (e.g., angiotensin II) factors will contribute to blood flow regulation in small fetoplacental vessels. Oxygenation (specifically hypoxia) has received particular attention. At the macro-level, hypoxic challenge increases vascular resistance, but the data's physiological relevance remains questionable. K(+) channels are a diverse family of proteins known to play important roles in the normal physiological functions of endothelial and smooth muscle cells of a variety of vascular beds. K(+) channels are categorized by their predicted transmembrane structure or gating properties. A small number of perfused placental cotyledon and isolated blood vessels studies have assessed K(+) channel activity. Specific activator/inhibitor application suggests functional voltage-gated channels, whereas toxin inhibitor studies have documented KCa channel activity. Pharmacological KATP channel activation significantly dilates preconstricted placental arteries and veins. There is a paucity of cell subtype-specific expression studies of placental K(+) channels. This review focuses on the roles of K(+) channels and oxygenation in controlling reactivity of small fetoplacental blood vessels.
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Affiliation(s)
- Mark Wareing
- Maternal and Fetal Health Research Centre, Institute of Human Development, University of Manchester, Manchester, UK; Maternal and Fetal Health Research Centre, St. Mary's Hospital, Central Manchester University Hospitals NHS Foundation Trust, Manchester Academic Health Science Centre, Manchester, UK
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Herrera EA, Krause B, Ebensperger G, Reyes RV, Casanello P, Parra-Cordero M, Llanos AJ. The placental pursuit for an adequate oxidant balance between the mother and the fetus. Front Pharmacol 2014; 5:149. [PMID: 25009498 PMCID: PMC4068002 DOI: 10.3389/fphar.2014.00149] [Citation(s) in RCA: 64] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2014] [Accepted: 06/06/2014] [Indexed: 11/13/2022] Open
Abstract
The placenta is the exchange organ that regulates metabolic processes between the mother and her developing fetus. The adequate function of this organ is clearly vital for a physiologic gestational process and a healthy baby as final outcome. The umbilico-placental vasculature has the capacity to respond to variations in the materno-fetal milieu. Depending on the intensity and the extensity of the insult, these responses may be immediate-, mediate-, and long-lasting, deriving in potential morphostructural and functional changes later in life. These adjustments usually compensate the initial insults, but occasionally may switch to long-lasting remodeling and dysfunctional processes, arising maladaptation. One of the most challenging conditions in modern perinatology is hypoxia and oxidative stress during development, both disorders occurring in high-altitude and in low-altitude placental insufficiency. Hypoxia and oxidative stress may induce endothelial dysfunction and thus, reduction in the perfusion of the placenta and restriction in the fetal growth and development. This Review will focus on placental responses to hypoxic conditions, usually related with high-altitude and placental insufficiency, deriving in oxidative stress and vascular disorders, altering fetal and maternal health. Although day-to-day clinical practice, basic and clinical research are clearly providing evidence of the severe impact of oxygen deficiency and oxidative stress establishment during pregnancy, further research on umbilical and placental vascular function under these conditions is badly needed to clarify the myriad of questions still unsettled.
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Affiliation(s)
- Emilio A Herrera
- Laboratorio de Función y Reactividad Vascular, Programa de Fisiopatología, Instituto de Ciencias Biomédicas, Facultad de Medicina, Universidad de Chile Santiago, Chile ; International Center for Andean Studies, Universidad de Chile Santiago, Chile
| | - Bernardo Krause
- División de Obstetricia y Ginecología, Facultad de Medicina, Pontificia Universidad Católica de Chile Santiago, Chile
| | - German Ebensperger
- Laboratorio de Función y Reactividad Vascular, Programa de Fisiopatología, Instituto de Ciencias Biomédicas, Facultad de Medicina, Universidad de Chile Santiago, Chile
| | - Roberto V Reyes
- Laboratorio de Función y Reactividad Vascular, Programa de Fisiopatología, Instituto de Ciencias Biomédicas, Facultad de Medicina, Universidad de Chile Santiago, Chile
| | - Paola Casanello
- División de Obstetricia y Ginecología, Facultad de Medicina, Pontificia Universidad Católica de Chile Santiago, Chile ; División de Pediatría, Facultad de Medicina, Pontificia Universidad Católica de Chile Santiago, Chile
| | - Mauro Parra-Cordero
- Unidad Materno-Fetal, Hospital Clínico Universidad de Chile, Universidad de Chile Santiago, Chile
| | - Anibal J Llanos
- Laboratorio de Función y Reactividad Vascular, Programa de Fisiopatología, Instituto de Ciencias Biomédicas, Facultad de Medicina, Universidad de Chile Santiago, Chile ; International Center for Andean Studies, Universidad de Chile Santiago, Chile
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Rueda-Clausen CF, Stanley JL, Thambiraj DF, Poudel R, Davidge ST, Baker PN. Effect of prenatal hypoxia in transgenic mouse models of preeclampsia and fetal growth restriction. Reprod Sci 2013; 21:492-502. [PMID: 24084523 DOI: 10.1177/1933719113503401] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Mice lacking endothelial nitric oxide synthase (eNOS(-)(/-)) or catechol-O-methyl transferase (COMT(-/-)) exhibit a preeclampsia-like phenotype and fetal growth restriction. We hypothesized that a hypoxic insult would result in a more severe phenotype. Pregnant eNOS(-/-), COMT(-/-) and control (C57BL/6J) mice were randomized to hypoxic (10.5% O(2)) or normal conditions (20.9% O(2)) from gestational day 10.5 to 18.5. Hypoxia increased the blood pressure in all genotypes and proteinuria in C57BL/6J and eNOS(-/-) mice. Fetal survival was significantly reduced following hypoxia, particularly in eNOS(-/-) mice. Birth weight was decreased in both C57BL/6J and COMT(-/-) mice. Placentas from COMT(-/-) mice demonstrated increased peroxynitrite. Despite similar hypoxia-induced effects on maternal blood pressure and proteinuria, eNOS(-/-) embryos have a decreased tolerance to hypoxia. Compared to C57BL/6J, COMT(-/-) mice exhibited less severe changes in proteinuria and fetal growth when exposed to prenatal hypoxia. This relative resistance to prenatal hypoxia was associated with a significant increase in placental levels of peroxynitrite.
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Affiliation(s)
- C F Rueda-Clausen
- 1Department of Obstetrics and Gynecology, University of Alberta, Edmonton, Alberta, Canada
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Stanley JL, Andersson IJ, Poudel R, Rueda-Clausen CF, Sibley CP, Davidge ST, Baker PN. Sildenafil citrate rescues fetal growth in the catechol-O-methyl transferase knockout mouse model. Hypertension 2012; 59:1021-8. [PMID: 22392899 DOI: 10.1161/hypertensionaha.111.186270] [Citation(s) in RCA: 95] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Preeclampsia and fetal growth restriction are responsible for the majority of maternal and perinatal morbidity and mortality associated with complicated pregnancies. Although their etiologies are complex and multifactorial, both are associated with increased uterine artery resistance. Sildenafil citrate is able to rescue the dysfunction observed ex vivo in uterine arteries of women with preeclampsia. The ability of sildenafil citrate to increase uterine artery vasodilation, thereby decreasing uterine artery resistance and, hence, ameliorated preeclampsia and fetal growth restriction, was tested in a mouse model of preeclampsia, the catechol-O-methyl transferase knockout mouse (COMT(-/-)). COMT(-/-) and C57BL/6J mice were treated (0.2 mg/mL in drinking water, n=6-12) from gestational day 12.5 to 18.5. Measures of pup growth, including body weight, crown/rump length, and abdominal circumference, were reduced in COMT(-/-) mice; this was normalized after treatment with Sildenafil. COMT(-/-) mice also demonstrated abnormal umbilical Doppler waveforms, including reverse arterial blood flow velocity. This was normalized after treatment with Sildenafil. Abnormal uterine artery Doppler waveforms were not demonstrated in COMT(-/-) mice, although ex vivo responses of uterine arteries to phenylephrine were increased; moreover, treatment with Sildenafil did improve ex vivo sensitivity to an endothelium-dependent vasodilator. The data presented here demonstrate that Sildenafil can rescue pup growth and improve abnormal umbilical Doppler waveforms, providing support for a potential new therapeutic strategy targeting fetal growth restriction.
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Affiliation(s)
- Joanna L Stanley
- Department of Obstetrics and Gynecology, University of Alberta, Edmonton, Alberta, Canada.
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Mihu D, Sabău L, Costin N, Ciortea R, Măluţan A, Mihu CM. Implications of maternal systemic oxidative stress in normal pregnancy and in pregnancy complicated by preeclampsia. J Matern Fetal Neonatal Med 2011; 25:944-51. [DOI: 10.3109/14767058.2011.600796] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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Wareing M, Greenwood SL. Review: Potassium channels in the human fetoplacental vasculature. Placenta 2011; 32 Suppl 2:S203-6. [PMID: 21227507 DOI: 10.1016/j.placenta.2010.12.022] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/15/2010] [Revised: 12/16/2010] [Accepted: 12/16/2010] [Indexed: 01/12/2023]
Abstract
Despite their fundamental importance for normal cellular function, potassium (K) channels have been poorly studied in placental vascular tissues. This lack of experimental focus may relate to the fact that, as yet, no pregnancy complications have been directly attributable to a specific "channelopathy". K channel activity is central to normal cellular function. Vascular smooth muscle and endothelial cells within the fetoplacental circulation would be expected to be heavily influenced by the behaviour of K channels, as has been well-documented in other vascular beds. In this review, we summarise current understanding of K channel expression and activity in fetoplacental vasculature in normal and complicated pregnancies.
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Affiliation(s)
- M Wareing
- Maternal and Fetal Health Research Centre, School of Biomedicine, The University of Manchester, St. Mary's Hospital, Manchester, UK.
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Negre-Salvayre A, Auge N, Ayala V, Basaga H, Boada J, Brenke R, Chapple S, Cohen G, Feher J, Grune T, Lengyel G, Mann GE, Pamplona R, Poli G, Portero-Otin M, Riahi Y, Salvayre R, Sasson S, Serrano J, Shamni O, Siems W, Siow RCM, Wiswedel I, Zarkovic K, Zarkovic N. Pathological aspects of lipid peroxidation. Free Radic Res 2010; 44:1125-71. [PMID: 20836660 DOI: 10.3109/10715762.2010.498478] [Citation(s) in RCA: 474] [Impact Index Per Article: 33.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Lipid peroxidation (LPO) product accumulation in human tissues is a major cause of tissular and cellular dysfunction that plays a major role in ageing and most age-related and oxidative stress-related diseases. The current evidence for the implication of LPO in pathological processes is discussed in this review. New data and literature review are provided evaluating the role of LPO in the pathophysiology of ageing and classically oxidative stress-linked diseases, such as neurodegenerative diseases, diabetes and atherosclerosis (the main cause of cardiovascular complications). Striking evidences implicating LPO in foetal vascular dysfunction occurring in pre-eclampsia, in renal and liver diseases, as well as their role as cause and consequence to cancer development are addressed.
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Williams PJ, Mistry HD, Innes BA, Bulmer JN, Broughton Pipkin F. Expression of AT1R, AT2R and AT4R and their roles in extravillous trophoblast invasion in the human. Placenta 2010; 31:448-55. [PMID: 20304486 DOI: 10.1016/j.placenta.2010.02.014] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/21/2009] [Revised: 02/22/2010] [Accepted: 02/23/2010] [Indexed: 10/19/2022]
Abstract
The placental renin-angiotensin system (RAS) is active from early pregnancy and may have a role in placentation. Angiotensin II (AngII) acts via binding to receptor types AT1R and AT2R. Recently smaller peptide members of the angiotensin family have been recognised as having biological relevance. Angiotensin (3-8) (AngIV) has a specific receptor (AT4R) and evokes hypertrophy, vasodilatation and vascular inflammatory response. The aim of this study was to characterise placental expression of AT1R, AT2R and AT4R, and to determine whether AngII and AngIV regulate extravillous trophoblast (EVT) invasion, apoptosis and proliferation. Placental samples were obtained from women undergoing elective surgical termination of pregnancy (TOP) at 8-10 weeks gestation (early TOP), 12-14 weeks gestation (mid TOP) or at delivery following normal pregnancy or with pre-eclampsia (PE). Immunohistochemistry and qRT-PCR were performed to determine placental mRNA and protein expression of AT1R, AT2R and AT4R at all gestational ages. EVT invasion following culture with AngII or AngIV was assessed in early placental tissue using Matrigel invasion assays. Invasion was assessed on day 6 of culture and placental explants were harvested for immunohistochemical analysis of apoptosis and proliferation. The results from qRT-PCR and immunohistochemistry showed placental AT1R expression which did not vary with gestation. The highest levels of expression of AT2R were found in early and mid TOP placentae compared to term pregnancy. Expression of AT4R was increased in term placentae, with a significant reduction in PE placentae. Moreover, culture with AngIV or AngII increased EVT invasion from placental explants, which showed increased trophoblast proliferation and reduced apoptosis. This study has characterised expression of AT4R and AT1R and AT2R in human placenta throughout normal pregnancy and in PE. Both AngIV and AngII may play an important role in normal pregnancy.
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Affiliation(s)
- P J Williams
- School of Clinical Sciences, University of Nottingham, City Hospital Nottingham, Nottingham NG5 1PB, United Kingdom
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