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McLeod RM, Rosenkrantz TS, Fitch RH, Koski RR. Sex Differences in Microglia Activation in a Rodent Model of Preterm Hypoxic Ischemic Injury with Caffeine Treatment. Biomedicines 2023; 11:biomedicines11010185. [PMID: 36672692 PMCID: PMC9855625 DOI: 10.3390/biomedicines11010185] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2022] [Revised: 12/23/2022] [Accepted: 01/04/2023] [Indexed: 01/15/2023] Open
Abstract
Preterm infants are often treated with caffeine as a respiratory stimulant. However, follow-up data shows caffeine may also have neuroprotective potential. There are several theories as to how caffeine might protect the brain, but none have been proven. This study looked at caffeine effects on microglial activation in rodent brains post hypoxic ischemic (HI) injury. Rat pups underwent either sham or HI surgery on P6, followed by treatment with either caffeine or saline. Forty-eight hours post-injury, brains were collected and underwent paraffin embedding and sectioning followed by immunofluorescence staining. Ionized calcium binding adaptor molecule 1 (Iba-1) was used to label microglia, and 4',6-diamindino-2-phenylindole (DAPI) was used to label DNA. Cell size measurements of microglia were obtained to gauge microglia activation, and chromatin condensation (DAPI optical density) was used as an index of neuronal cell death. Results suggest that caffeine does offer protective effects, based on significantly increased levels of cell death in HI-saline animals not seen in caffeine-treated HI males and females. However, the mechanism of action may be different. Male HI animals showed marginally reduced microglial activation following caffeine treatment, whereas females did not. Results indicate that though caffeine may act protectively in both sexes by reducing cell death, the benefits may be mediated by different mechanisms.
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Affiliation(s)
- Ruth Mae McLeod
- Behavioral Neuroscience Division, Department of Psychological Sciences, University of Connecticut, Storrs, CT 06269, USA
- Correspondence:
| | - Ted S. Rosenkrantz
- Department of Pediatrics, University of Connecticut Health Center and Connecticut Children’s Hospital, Farmington, CT 06030, USA
| | - Roslyn Holly Fitch
- Behavioral Neuroscience Division, Department of Psychological Sciences, University of Connecticut, Storrs, CT 06269, USA
| | - Rachel R. Koski
- Division of Neonatology, Department of Pediatrics, University of Minnesota, Minneapolis, MN 55454, USA
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2
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Colangelo MT, Galli C, Guizzardi S. The effects of polydeoxyribonucleotide on wound healing and tissue regeneration: a systematic review of the literature. Regen Med 2020; 15:1801-1821. [PMID: 32757710 DOI: 10.2217/rme-2019-0118] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
Aim: The present study evaluated the effects of polydeoxyribonucleotide (PDRN) on tissue regeneration, paying special attention to the molecular mechanisms that underlie its tissue remodeling actions to better identify its effective therapeutic potential in wound healing. Materials & methods: Strategic searches were conducted through MEDLINE/PubMed, Google Scholar, Scopus, Web of Science and the Cochrane Central Register of Controlled Trials, from their earliest available dates to March 2020. The studies were included with the following eligibility criteria: studies evaluating tissue regeneration, and being an in vitro, in vivo and clinical study. Results: Out of more than 90 articles, 34 fulfilled the eligibility criteria. All data obtained proved the ability of PDRN in promoting a physiological tissue repair through salvage pathway and adenosine A2A receptor activation. Conclusion: Up to date PDRN has proved promising results in term of wound regeneration, healing time and absence of side effects.
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Affiliation(s)
- Maria T Colangelo
- Department of Medicine & Surgery, Histology & Embryology Lab, University of Parma, Parma, Italy
| | - Carlo Galli
- Department of Medicine & Surgery, University of Parma, Parma, Italy
| | - Stefano Guizzardi
- Department of Medicine & Surgery, Histology & Embryology Lab, University of Parma, Parma, Italy
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3
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Wang L, Zhang J. Exosomal lncRNA AK139128 Derived from Hypoxic Cardiomyocytes Promotes Apoptosis and Inhibits Cell Proliferation in Cardiac Fibroblasts. Int J Nanomedicine 2020; 15:3363-3376. [PMID: 32494135 PMCID: PMC7229807 DOI: 10.2147/ijn.s240660] [Citation(s) in RCA: 46] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2019] [Accepted: 04/08/2020] [Indexed: 01/04/2023] Open
Abstract
Introduction Myocardial infarction (MI) is the leading cause of congestive heart failure and mortality. Hypoxia is an important trigger in the cardiac remodeling of the myocardium in the development and progression of cardiac diseases. Objective Thus, we aimed to investigate the effect of hypoxia-induced exosomes on cardiac fibroblasts (CFs) and its related mechanisms. Materials and Methods In this study, we successfully isolated and identified the exosomes from hypoxic cardiomyocytes (CMs). Exosomes derived from hypoxic CMs promoted apoptosis and inhibited proliferation, migration, and invasion in CFs. RNA-Seq assay suggested that long noncoding RNA AK139128 (lncRNA AK139128) was found to overexpress in both hypoxic CMs and CMs-secreting exosomes. After coculturing with CFs, hypoxic exosomes increased the expression of AK139128 in recipient CFs. Moreover, exosomal AK139128 derived from hypoxic CMs stimulated CFs apoptosis and inhibited proliferation, migration, and invasion. Furthermore, the effect of exosomal AK139128 derived from hypoxic CMs could also exacerbate MI in the rat model. Conclusion Taken together, hypoxia upregulated the level of AK139128 in CMs and exosomes and exosomal AK139128 derived from hypoxic CMs modulated cellular activities of CFs in vitro and in vivo. This study provides a new understanding of the mechanism underlying hypoxia-related cardiac diseases and insight into developing new therapeutic strategies.
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Affiliation(s)
- Lei Wang
- Cardiovascular Department, Cangzhou Central Hospital, Cangzhou, Hebei Province 061001, People's Republic of China
| | - Jun Zhang
- Cardiovascular Department, Cangzhou Central Hospital, Cangzhou, Hebei Province 061001, People's Republic of China
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Envain F, Vandendriessche D, Mehros W, Houfflin-Debarge V, Garabedian C, Rakza T. Discordant immune complete heart block and growth restriction in dichorionic twin pregnancy with permanent pacemaker implantation of an 1140 g neonate. J Gynecol Obstet Hum Reprod 2019; 48:699-701. [PMID: 31075433 DOI: 10.1016/j.jogoh.2019.05.002] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2018] [Revised: 04/16/2019] [Accepted: 05/02/2019] [Indexed: 10/26/2022]
Abstract
Fetal atrioventricular block is a rare pathology, mostly due to placental transmission of maternal SSA/Ro and SSB/La antibodies, and can lead to severe fetal or neonatal outcomes. We report a case of dichorionic, diamniotic twin pregnancy, with maternal SSA/Ro antibodies. Isolated complete atrioventricular block was diagnosed at 23 weeks in one fetus (Twin A), while the second fetus (Twin B) remained in normal sinus rhythm. Severe asymmetric intrauterine growth restriction occurred in Twin A. Delivery was by caesarean section at 32 + 2 weeks. Neonatal permanent pacemaker was inserted on the first day after birth in 1140 g neonate. Discordant heart block in twin pregnancy has already been reported in a few dichorionic pregnancies, but the pathway of discordant disease expression remains unclear. Extraction decision is a dilemma between cardiac failure prevention and prematurity associated twin morbidity. This case shows a successful pacing in a very low birth weight neonate.
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Affiliation(s)
- François Envain
- Hôpital Jeanne de Flandre, clinique d'obstétrique, CHU de Lille, 59037 Lille Cedex, France.
| | - David Vandendriessche
- Hôpital Jeanne de Flandre, clinique d'obstétrique, CHU de Lille, 59037 Lille Cedex, France
| | - Wala Mehros
- Hôpital Jeanne de Flandre, clinique d'obstétrique, CHU de Lille, 59037 Lille Cedex, France
| | | | - Charles Garabedian
- Hôpital Jeanne de Flandre, clinique d'obstétrique, CHU de Lille, 59037 Lille Cedex, France
| | - Thameur Rakza
- Hôpital Jeanne de Flandre, clinique d'obstétrique, CHU de Lille, 59037 Lille Cedex, France; Hôpital Jeanne de Flandre, Service de pédiatrie en maternité, CHU de Lille 59037, Lille Cedex, France; Hôpital Jeanne de Flandre, Service de cardiologie pédiatrique et foetale, France
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5
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Ahmed M, Miller E. Macrophage migration inhibitory factor (MIF) in the development and progression of pulmonary arterial hypertension. Glob Cardiol Sci Pract 2018; 2018:14. [PMID: 30083544 PMCID: PMC6062764 DOI: 10.21542/gcsp.2018.14] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2018] [Accepted: 04/18/2018] [Indexed: 02/06/2023] Open
Abstract
Macrophage migration inhibitory factor (MIF) has been described as a pro-inflammatory cytokine and regulator of neuro-endocrine function. It plays an important upstream role in the inflammatory cascade by promoting the release of other inflammatory cytokines such as TNF-alpha and IL-6, ultimately triggering a chronic inflammatory immune response. As lungs can synthesize and release MIF, many studies have investigated the potential role of MIF as a biomarker in assessment of patients with pulmonary arterial hypertension (PAH) and using anti-MIFs as a new therapeutic modality for PAH.
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Affiliation(s)
- Mohamed Ahmed
- Neonatal-Perinatal Medicine, Pediatrics Department Cohen Children’s Hospital at New York, Northwell Health System
- The Center for Heart and Lung Research, The Feinstein Institute for Medical Research, Manhasset, New York, USA
- School of Medicine, Hofstra University, Hempstead, New York, USA
| | - Edmund Miller
- The Center for Heart and Lung Research, The Feinstein Institute for Medical Research, Manhasset, New York, USA
- School of Medicine, Hofstra University, Hempstead, New York, USA
- The Elmezzi Graduate School of Molecular Medicine, Manhasset, New York, USA
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TRPM7 regulates angiotensin II-induced sinoatrial node fibrosis in sick sinus syndrome rats by mediating Smad signaling. Heart Vessels 2018; 33:1094-1105. [PMID: 29511803 PMCID: PMC6096742 DOI: 10.1007/s00380-018-1146-0] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/12/2017] [Accepted: 03/02/2018] [Indexed: 01/09/2023]
Abstract
Sinoatrial node fibrosis is involved in the pathogenesis of sinus sick syndrome (SSS). Transient receptor potential (TRP) subfamily M member 7 (TRPM7) is implicated in cardiac fibrosis. However, the mechanisms underlying the regulation of sinoatrial node (SAN) fibrosis in SSS by TRPM7 remain unknown. The aim of this study was to investigate the role of angiotensin II (Ang II)/TRPM7/Smad pathway in the SAN fibrosis in rats with SSS. The rat SSS model was established with sodium hydroxide pinpoint pressing permeation. Forty-eight rats were randomly divided into six groups: normal control (ctrl), sham operation (sham), postoperative 1-, 2-, 3-, and 4-week SSS, respectively. The tissue explant culture method was used to culture cardiac fibroblasts (CFs) from rat SAN tissues. TRPM7 siRNA or encoding plasmids were used to knock down or overexpress TRPM7. Collagen (Col) distribution in SAN and atria was assessed using PASM–Masson staining. Ang II, Col I, and Col III levels in serum and tissues or in CFs were determined by ELISA. TRPM7, smad2 and p-smad2 levels were evaluated by real-time PCR, and/or western blot and immunohistochemistry. SAN and atria in rats of the SSS groups had more fibers and higher levels of Ang II, Col I and III than the sham rats. Similar findings were obtained for TRPM7 and pSmad2 expression. In vitro, Ang II promoted CFs collagen synthesis in a dose-dependent manner, and potentiated TRPM7 and p-Smad2 expression. TRPM7 depletion inhibited Ang II-induced p-Smad2 expression and collagen synthesis in CFs, whereas increased TRPM7 expression did the opposite. SAN fibrosis is regulated by the Ang II/TRPM7/Smad pathway in SSS, indicating that TRPM7 is a potential target for SAN fibrosis therapy in SSS.
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7
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Can the Drosophila model help in paving the way for translational medicine in heart failure? Biochem Soc Trans 2017; 44:1549-1560. [PMID: 27911738 DOI: 10.1042/bst20160017c] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2016] [Revised: 08/02/2016] [Accepted: 08/15/2016] [Indexed: 01/09/2023]
Abstract
Chronic heart failure is a common consequence of various heart diseases. Mechanical force is known to play a key role in heart failure development through regulating cardiomyocyte hypertrophy. In order to understand the complex disease mechanism, this article discussed a multi-disciplinary approach that may aid the illustration of heart failure molecular process.
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8
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Ugolini GS, Pavesi A, Rasponi M, Fiore GB, Kamm R, Soncini M. Human cardiac fibroblasts adaptive responses to controlled combined mechanical strain and oxygen changes in vitro. eLife 2017; 6. [PMID: 28315522 PMCID: PMC5407858 DOI: 10.7554/elife.22847] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2016] [Accepted: 03/17/2017] [Indexed: 12/21/2022] Open
Abstract
Upon cardiac pathological conditions such as ischemia, microenvironmental changes instruct a series of cellular responses that trigger cardiac fibroblasts-mediated tissue adaptation and inflammation. A comprehensive model of how early environmental changes may induce cardiac fibroblasts (CF) pathological responses is far from being elucidated, partly due to the lack of approaches involving complex and simultaneous environmental stimulation. Here, we provide a first analysis of human primary CF behavior by means of a multi-stimulus microdevice for combined application of cyclic mechanical strain and controlled oxygen tension. Our findings elucidate differential human CFs responses to different combinations of the above stimuli. Individual stimuli cause proliferative effects (PHH3+ mitotic cells, YAP translocation, PDGF secretion) or increase collagen presence. Interestingly, only the combination of hypoxia and a simulated loss of contractility (2% strain) is able to additionally induce increased CF release of inflammatory and pro-fibrotic cytokines and matrix metalloproteinases. DOI:http://dx.doi.org/10.7554/eLife.22847.001 When the supply of oxygen to the heart is reduced, its cells start to die within hours, the heart muscle becomes less able to contract, and the area becomes inflamed. This inflammation is accompanied by an influx of immune cells. It also activates other cells known as cardiac fibroblasts that help to break down the framework of molecules that supported the damaged heart tissue and replace it with a scar. This response is part of the normal repair process, but it can lead to the formation of scar tissue in non-damaged areas of the heart. Excess scar tissue makes the heart muscle less able to contract and increases the affected individual’s chance of dying. Understanding how this repair process works is an important step in developing strategies to minimise the damage caused by coronary artery disease or heart attacks. However, existing laboratory models are only partly able to recreate the conditions seen in real heart tissue. To properly understand the response at the level of living cells, a more complete model is needed. Ugolini et al. now report improvements to a small device, referred to as a lab-on-chip, that can subject cells to mechanical strain. The improvements mean the device could also recreate other conditions seen early on in damaged heart tissue, specifically the reduced supply of oxygen. Replicating combinations of mechanical changes and oxygen supplies meant that the impact of these conditions on human cardiac fibroblasts could be directly observed in the laboratory for the first time. Ugolini et al. found that a lack of contraction and low oxygen levels triggered the cardiac fibroblasts to produce inflammatory molecules and molecules associated with the formation of scar tissue. This resembles the response seen in living hearts. The next step is to improve the lab-on-chip device further by adding other cell types, including heart muscle cells and immune cells. A more complete model may aid future research into how our hearts operate in both health and disease. DOI:http://dx.doi.org/10.7554/eLife.22847.002
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Affiliation(s)
| | - Andrea Pavesi
- Institute of Molecular and Cell Biology, Agency for Science, Technology and Research, Singapore, Singapore.,Biosym IRG, Singapore-MIT Alliance for Research and Technology, Singapore, Singapore
| | - Marco Rasponi
- Department of Electronics, Information and Bioengineering, Politecnico di Milano, Milan, Italy
| | | | - Roger Kamm
- Biosym IRG, Singapore-MIT Alliance for Research and Technology, Singapore, Singapore.,Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, United States
| | - Monica Soncini
- Department of Electronics, Information and Bioengineering, Politecnico di Milano, Milan, Italy
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9
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Grönwall C, Clancy RM, Getu L, Lloyd KA, Siegel DL, Reed JH, Buyon JP, Silverman GJ. Modulation of natural IgM autoantibodies to oxidative stress-related neo-epitopes on apoptotic cells in newborns of mothers with anti-Ro autoimmunity. J Autoimmun 2016; 73:30-41. [PMID: 27289167 DOI: 10.1016/j.jaut.2016.05.014] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2016] [Revised: 05/26/2016] [Accepted: 05/31/2016] [Indexed: 11/17/2022]
Abstract
At birth, the human immune system already contains substantial levels of polymeric IgM, that include autoantibodies to neo-epitopes on apoptotic cells (ACs) that are proposed to play homeostatic and anti-inflammatory roles. Yet the biologic origins and developmental regulation of these naturally arising antibodies remain poorly understood. Herein, we report that levels of IgM-antibodies to malondialdehyde (MDA) protein adducts, a common type of in vivo generated oxidative stress-related neoepitope, directly correlate with the relative binding of neonatal-IgM to ACs. Levels of IgM to phosphorylcholine (PC), a natural antibody prevalent in adults, were relatively scant in cord blood, while there was significantly greater relative representation of IgM anti-MDA antibodies in newborns compared to adults. To investigate the potential interrelationships between neonatal IgM with pathogenic IgG-autoantibodies, we studied 103 newborns born to autoimmune mothers with IgG anti-Ro (i.e., 70 with neonatal lupus and 33 without neonatal lupus). In these subjects the mean levels of IgM anti-Ro60 were significantly higher than in the newborns from non-autoimmune mothers. In contrast, levels of IgM anti-MDA in IgG anti-Ro exposed neonates were significantly lower than in neonates from non-autoimmune mothers. The presence or absence of neonatal lupus did not appear to influence the total levels of IgM in the anti-Ro exposed newborns. Taken together, our studies provide evidence that the immune development of the natural IgM-repertoire may be affected, and become imprinted by, the transfer of maternal IgG into the fetus.
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Affiliation(s)
- Caroline Grönwall
- Department of Medicine, Division of Rheumatology, New York University School of Medicine, New York, NY 10016, USA; Department of Medicine, Unit of Rheumatology, Karolinska Institutet, Karolinska University Hospital, Stockholm, Sweden
| | - Robert M Clancy
- Department of Medicine, Division of Rheumatology, New York University School of Medicine, New York, NY 10016, USA
| | - Lelise Getu
- Department of Medicine, Division of Rheumatology, New York University School of Medicine, New York, NY 10016, USA
| | - Katy A Lloyd
- Department of Medicine, Unit of Rheumatology, Karolinska Institutet, Karolinska University Hospital, Stockholm, Sweden
| | - Don L Siegel
- Department of Pathology and Laboratory Medicine, Division of Transfusion Medicine & Therapeutic Pathology, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Joanne H Reed
- Department of Medicine, Division of Rheumatology, New York University School of Medicine, New York, NY 10016, USA
| | - Jill P Buyon
- Department of Medicine, Division of Rheumatology, New York University School of Medicine, New York, NY 10016, USA
| | - Gregg J Silverman
- Department of Medicine, Division of Rheumatology, New York University School of Medicine, New York, NY 10016, USA.
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10
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Schultz F, Hasan A, Alvarez-Laviada A, Miragoli M, Bhogal N, Wells S, Poulet C, Chambers J, Williamson C, Gorelik J. The protective effect of ursodeoxycholic acid in an in vitro model of the human fetal heart occurs via targeting cardiac fibroblasts. PROGRESS IN BIOPHYSICS AND MOLECULAR BIOLOGY 2016; 120:149-63. [PMID: 26777584 DOI: 10.1016/j.pbiomolbio.2016.01.003] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/15/2015] [Revised: 01/05/2016] [Accepted: 01/06/2016] [Indexed: 12/27/2022]
Abstract
Bile acids are elevated in the blood of women with intrahepatic cholestasis of pregnancy (ICP) and this may lead to fetal arrhythmia, fetal hypoxia and potentially fetal death in utero. The bile acid taurocholic acid (TC) causes abnormal calcium dynamics and contraction in neonatal rat cardiomyocytes. Ursodeoxycholic acid (UDCA), a drug clinically used to treat ICP, prevents adverse effects of TC. During development, the fetus is in a state of relative hypoxia. Although this is essential for the development of the heart and vasculature, resident fibroblasts can transiently differentiate into myofibroblasts and form gap junctions with cardiomyocytes in vitro, resulting in cardiomyocyte depolarization. We expanded on previously published work using an in vitro hypoxia model to investigate the differentiation of human fetal fibroblasts into myofibroblasts. Recent evidence shows that potassium channels are involved in maintaining the membrane potential of ventricular fibroblasts and that ATP-dependent potassium (KATP) channel subunits are expressed in cultured fibroblasts. KATP channels are a valuable target as they are thought to have a cardioprotective role during ischaemic and hypoxic conditions. We investigated whether UDCA could modulate fibroblast membrane potential. We established the isolation and culture of human fetal cardiomyocytes and fibroblasts to investigate the effect of hypoxia, TC and UDCA on human fetal cardiac cells. UDCA hyperpolarized myofibroblasts and prevented TC-induced depolarisation, possibly through the activation of KATP channels that are expressed in cultured fibroblasts. Also, similar to the rat model, UDCA can counteract TC-induced calcium abnormalities in human fetal cultures of cardiomyocytes and myofibroblasts. Under normoxic conditions, we found a higher number of myofibroblasts in cultures derived from human fetal hearts compared to cells isolated from neonatal rat hearts, indicating a possible increased number of myofibroblasts in human fetal hearts. Hypoxia further increased the number of human fetal and rat neonatal myofibroblasts. However, chronically administered UDCA reduced the number of myofibroblasts and prevented hypoxia-induced depolarisation. In conclusion, our results show that the protective effect of UDCA involves both the reduction of fibroblast differentiation into myofibroblasts, and hyperpolarisation of myofibroblasts, most likely through the stimulation of potassium channels, i.e. KATP channels. This could be important in validating UDCA as an antifibrotic and antiarrhythmic drug for treatment of failing hearts and fetal arrhythmia.
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Affiliation(s)
- Francisca Schultz
- National Heart and Lung Institute, Imperial Centre for Translational and Experimental Medicine, Imperial College London, London, UK; Institute of Reproductive and Developmental Biology, Imperial College London, London, UK
| | - Alveera Hasan
- National Heart and Lung Institute, Imperial Centre for Translational and Experimental Medicine, Imperial College London, London, UK
| | - Anita Alvarez-Laviada
- National Heart and Lung Institute, Imperial Centre for Translational and Experimental Medicine, Imperial College London, London, UK
| | - Michele Miragoli
- National Heart and Lung Institute, Imperial Centre for Translational and Experimental Medicine, Imperial College London, London, UK; Humanitas Clinical and Research Institute, Rozzano, Italy
| | - Navneet Bhogal
- National Heart and Lung Institute, Imperial Centre for Translational and Experimental Medicine, Imperial College London, London, UK
| | - Sarah Wells
- National Heart and Lung Institute, Imperial Centre for Translational and Experimental Medicine, Imperial College London, London, UK
| | - Claire Poulet
- National Heart and Lung Institute, Imperial Centre for Translational and Experimental Medicine, Imperial College London, London, UK
| | - Jenny Chambers
- Institute of Reproductive and Developmental Biology, Imperial College London, London, UK; Women's Health Academic Centre, King's College London, London, United Kingdom
| | - Catherine Williamson
- Institute of Reproductive and Developmental Biology, Imperial College London, London, UK; Women's Health Academic Centre, King's College London, London, United Kingdom
| | - Julia Gorelik
- National Heart and Lung Institute, Imperial Centre for Translational and Experimental Medicine, Imperial College London, London, UK.
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Zhao X, Wang K, Hu F, Qian C, Guan H, Feng K, Zhou Y, Chen Z. MicroRNA-101 protects cardiac fibroblasts from hypoxia-induced apoptosis via inhibition of the TGF-β signaling pathway. Int J Biochem Cell Biol 2015; 65:155-64. [DOI: 10.1016/j.biocel.2015.06.005] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2015] [Revised: 05/26/2015] [Accepted: 06/04/2015] [Indexed: 12/12/2022]
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12
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Atrial Fibrillation and Fibrosis: Beyond the Cardiomyocyte Centric View. BIOMED RESEARCH INTERNATIONAL 2015; 2015:798768. [PMID: 26229964 PMCID: PMC4502285 DOI: 10.1155/2015/798768] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/31/2014] [Revised: 03/27/2015] [Accepted: 03/30/2015] [Indexed: 12/31/2022]
Abstract
Atrial fibrillation (AF) associated with fibrosis is characterized by the appearance of interstitial myofibroblasts. These cells are responsible for the uncontrolled deposition of the extracellular matrix, which pathologically separate cardiomyocyte bundles. The enhanced fibrosis is thought to contribute to arrhythmias “indirectly” because a collagenous septum is a passive substrate for propagation, resulting in impulse conduction block and/or zigzag conduction. However, the emerging results demonstrate that myofibroblasts in vitro also promote arrhythmogenesis due to direct implications upon cardiomyocyte electrophysiology. This electrical interference may be considered beneficial as it resolves any conduction blocks; however, the passive properties of myofibroblasts might cause a delay in impulse propagation, thus promoting AF due to discontinuous slow conduction. Moreover, low-polarized myofibroblasts reduce, via cell-density dependence, the fast driving inward current for cardiac impulse conduction, therefore resulting in arrhythmogenic uniformly slow propagation. Critically, the subsequent reduction in cardiomyocytes resting membrane potential in vitro significantly increases the likelihood of ectopic activity. Myofibroblast densities and the degree of coupling at cellular border zones also impact upon this likelihood. By considering future in vivo studies, which identify myofibroblasts “per se” as a novel targets for cardiac arrhythmias, this review aims to describe the implications of noncardiomyocyte view in the context of AF.
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CAI ZHIGANG, LI HAITAO, ZHANG HEFANG, HAN SHUO, AN RUIJIN, YAN XIXIN. Novel insights into the role of hypoxia-inducible factor-1 in the pathogenesis of human post-intubation tracheal stenosis. Mol Med Rep 2013; 8:903-8. [DOI: 10.3892/mmr.2013.1595] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2013] [Accepted: 07/18/2013] [Indexed: 11/06/2022] Open
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Insel PA, Murray F, Yokoyama U, Romano S, Yun H, Brown L, Snead A, Lu D, Aroonsakool N. cAMP and Epac in the regulation of tissue fibrosis. Br J Pharmacol 2012; 166:447-56. [PMID: 22233238 DOI: 10.1111/j.1476-5381.2012.01847.x] [Citation(s) in RCA: 112] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Fibrosis, the result of excess deposition of extracellular matrix (ECM), in particular collagen, leads to scarring and loss of function in tissues that include the heart, lung, kidney and liver. The second messenger cAMP can inhibit the formation and extent of ECM during this late phase of inflammation, but the mechanisms for these actions of cAMP and of agents that elevate tissue cAMP levels are not well understood. In this article, we review the fibrotic process and focus on two recently recognized aspects of actions of cAMP and its effector Epac (Exchange protein activated by cAMP): (a) blunting of epithelial-mesenchymal transformation (EMT) and (b) down-regulation of Epac expression by profibrotic agents (e.g. TGF-β, angiotensin II), which may promote tissue fibrosis by decreasing Epac-mediated antifibrotic actions. Pharmacological approaches that raise cAMP or blunt the decrease in Epac expression by profibrotic agents may thus be strategies to block or perhaps reverse tissue fibrosis. LINKED ARTICLES This article is part of a themed section on Novel cAMP Signalling Paradigms. To view the other articles in this section visit http://dx.doi.org/10.1111/bph.2012.166.issue-2.
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Affiliation(s)
- Paul A Insel
- Departments of Pharmacology Medicine, University of California San Diego, La Jolla, CA 92093, USA.
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Chen W, Frangogiannis NG. Fibroblasts in post-infarction inflammation and cardiac repair. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2012; 1833:945-53. [PMID: 22982064 DOI: 10.1016/j.bbamcr.2012.08.023] [Citation(s) in RCA: 192] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/02/2012] [Revised: 08/29/2012] [Accepted: 08/31/2012] [Indexed: 02/07/2023]
Abstract
Fibroblasts are the predominant cell type in the cardiac interstitium. As the main matrix-producing cells in the adult mammalian heart, fibroblasts maintain the integrity of the extracellular matrix network, thus preserving geometry and function. Following myocardial infarction fibroblasts undergo dynamic phenotypic alterations and direct the reparative response. Due to their strategic location, cardiac fibroblasts serve as sentinel cells that sense injury and activate the inflammasome secreting cytokines and chemokines. During the proliferative phase of healing, infarct fibroblasts undergo myofibroblast transdifferentiation forming stress fibers and expressing contractile proteins (such as α-smooth muscle actin). Mechanical stress, transforming growth factor (TGF)-β/Smad3 signaling and alterations in the composition of the extracellular matrix induce acquisition of the myofibroblast phenotype. In the highly cellular and growth factor-rich environment of the infarct, activated myofibroblasts produce matrix proteins, proteases and their inhibitors regulating matrix metabolism. As the infarct matures, "stress-shielding" of myofibroblasts by the cross-linked matrix and growth factor withdrawal may induce quiescence and ultimately cause apoptotic death. Because of their critical role in post-infarction cardiac remodeling, fibroblasts are promising therapeutic targets following myocardial infarction. However, the complexity of fibroblast functions and the pathophysiologic heterogeneity of post-infarction remodeling in the clinical context discourage oversimplified approaches in clinical translation. This article is part of a Special Issue entitled: Cardiomyocyte Biology: Cardiac Pathways of Differentiation, Metabolism and Contraction.
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Affiliation(s)
- Wei Chen
- Department of Medicine, Albert Einstein College of Medicine, Bronx NY, USA
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16
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Takahashi K, Sakamoto K, Kimura J. Hypoxic stress induces transient receptor potential melastatin 2 (TRPM2) channel expression in adult rat cardiac fibroblasts. J Pharmacol Sci 2012; 118:186-97. [PMID: 22293297 DOI: 10.1254/jphs.11128fp] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/14/2022] Open
Abstract
When cardiac tissue is exposed to hypoxia, myocytes are damaged, while fibroblasts are activated. However, it is unknown what changes are induced by hypoxia in cardiac fibroblasts. In this study, using the whole cell patch-clamp technique, we investigated the effect of hypoxia on membrane currents in fibroblasts primarily cultured from adult rat hearts. Cardiac fibroblasts were incubated for 24 h under normoxic or hypoxic conditions using Anaeropack. Hypoxia increased a current which reversed at around -20 mV in the cardiac fibroblasts. This current was inhibited by clotrimazole, which is an inhibitor of transient receptor potential melastatin 2 (TRPM2) channel and intermediate-conductance Ca(2+)-activated K(+) channel (KCa3.1). ADP ribose in the pipette solution enhanced this current. Quantitative RT-PCR revealed that mRNA of TRPM2, but not that of KCa3.1, was increased by hypoxia. RNA interference of TRPM2 prevented the development of the hypoxia-induced current. H(2)O(2), an activator of TRPM2 channel, induced a higher [Ca(2+)](i) elevation in hypoxia-exposed cardiac fibroblasts than that in normoxia-exposed cells. We conclude that hypoxia induces TRPM2 channel expression in adult rat cardiac fibroblasts.
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Affiliation(s)
- Kenji Takahashi
- Department of Pharmacology, Fukushima Medical University, School of Medicine, Japan.
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Miragoli M, Kadir SHSA, Sheppard MN, Salvarani N, Virta M, Wells S, Lab MJ, Nikolaev VO, Moshkov A, Hague WM, Rohr S, Williamson C, Gorelik J. A protective antiarrhythmic role of ursodeoxycholic acid in an in vitro rat model of the cholestatic fetal heart. Hepatology 2011; 54:1282-92. [PMID: 21809354 PMCID: PMC4900448 DOI: 10.1002/hep.24492] [Citation(s) in RCA: 58] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/24/2011] [Accepted: 06/02/2011] [Indexed: 12/27/2022]
Abstract
UNLABELLED Intrahepatic cholestasis of pregnancy may be complicated by fetal arrhythmia, fetal hypoxia, preterm labor, and, in severe cases, intrauterine death. The precise etiology of fetal death is not known. However, taurocholate has been demonstrated to cause arrhythmia and abnormal calcium dynamics in cardiomyocytes. To identify the underlying reason for increased susceptibility of fetal cardiomyocytes to arrhythmia, we studied myofibroblasts (MFBs), which appear during structural remodeling of the adult diseased heart. In vitro, they depolarize rat cardiomyocytes via heterocellular gap junctional coupling. Recently, it has been hypothesized that ventricular MFBs might appear in the developing human heart, triggered by physiological fetal hypoxia. However, their presence in the fetal heart (FH) and their proarrhythmogenic effects have not been systematically characterized. Immunohistochemistry demonstrated that ventricular MFBs transiently appear in the human FH during gestation. We established two in vitro models of the maternal heart (MH) and FH, both exposed to increasing doses of taurocholate. The MH model consisted of confluent strands of rat cardiomyocytes, whereas for the FH model, we added cardiac MFBs on top of cardiomyocytes. Taurocholate in the FH model, but not in the MH model, slowed conduction velocity from 19 to 9 cm/s, induced early after depolarizations, and resulted in sustained re-entrant arrhythmias. These arrhythmic events were prevented by ursodeoxycholic acid, which hyperpolarized MFB membrane potential by modulating potassium conductance. CONCLUSION These results illustrate that the appearance of MFBs in the FH may contribute to arrhythmias. The above-described mechanism represents a new therapeutic approach for cardiac arrhythmias at the level of MFB.
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Affiliation(s)
- Michele Miragoli
- National Heart and Lung Institute, Imperial College London, London, England
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18
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Olson N, van der Vliet A. Interactions between nitric oxide and hypoxia-inducible factor signaling pathways in inflammatory disease. Nitric Oxide 2011; 25:125-37. [PMID: 21199675 DOI: 10.1016/j.niox.2010.12.010] [Citation(s) in RCA: 99] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2010] [Revised: 12/22/2010] [Accepted: 12/29/2010] [Indexed: 02/06/2023]
Abstract
Induction and activation of nitric oxide (NO) synthases (NOS) and excessive production of NO are common features of almost all diseases associated with infection and acute or chronic inflammation, although the contribution of NO to the pathophysiology of these diseases is highly multifactorial and often still a matter of controversy. Because of its direct impact on tissue oxygenation and cellular oxygen (O(2)) consumption and re-distribution, the ability of NO to regulate various aspects of hypoxia-induced signaling has received widespread attention. Conditions of tissue hypoxia and the activation of hypoxia-inducible factors (HIF) have been implicated in hypoxia or in cancer biology, but are also being increasingly recognized as important features of acute and chronic inflammation. Thus, the activation of HIF transcription factors has been increasingly implicated in inflammatory diseases, and recent studies have indicated its critical importance in regulating phagocyte function, inflammatory mediator production, and regulation of epithelial integrity and repair processes. Finally, HIF also appears to contribute to important features of tissue fibrosis and epithelial-to-mesenchymal transition, processes that are associated with tissue remodeling in various non-malignant chronic inflammatory disorders. In this review, we briefly summarize the current state of knowledge with respect to the general mechanisms involved in HIF regulation and the impact of NO on HIF activation. Secondly, we will summarize the major recent findings demonstrating a role for HIF signaling in infection, inflammation, and tissue repair and remodeling, and will address the involvement of NO. The growing interest in hypoxia-induced signaling and its relation with NO biology is expected to lead to further insights into the complex roles of NO in acute or chronic inflammatory diseases and may point to the importance of HIF signaling as key feature of NO-mediated events during these disorders.
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Affiliation(s)
- Nels Olson
- Department of Pathology, College of Medicine, University of Vermont, Burlington, VT 05405, USA
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19
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Feng Y, Caiping M, Li C, Can R, Feichao X, Li Z, Zhice X. Fetal and offspring arrhythmia following exposure to nicotine during pregnancy. J Appl Toxicol 2010; 30:53-8. [PMID: 19728315 DOI: 10.1002/jat.1471] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
Although recent studies have demonstrated prenatal nicotine can increase cardiovascular risk in the offspring, it is unknown whether exposure to nicotine during pregnancy also may be a risk for development of arrhythmia in the offspring. In addition, in previous studies of fetal arrhythmia affected by smoking, only two patterns, bradycardia and tachycardia, were observed. The present study examined acute effects of maternal nicotine on the fetal arrhythmia in utero, and chronic influence on offspring arrhythmia at adult stage following prenatal exposure to nicotine. Nicotine was administered to pregnant ewes and rats. In the fetal sheep, intravenous nicotine not only induced changes of fetal heart rate, but also caused cardiac cycle irregularity, single and multiple dropped cardiac cycles. Although maternal nicotine had no influence on fetal blood pH, lactic acid, hemocrit, Na(+), K(+) levels and plasma osmolality, fetal blood PO(2) levels were significantly decreased following maternal nicotine in ewes. In offspring rats at 4-5 months after birth, prenatal exposure to nicotine significantly increased heart rate and premature ventricular contraction in restraint stress. In addition, arrhythmias induced by injection of nicotine were higher in the offspring prenatal exposure to nicotine in utero. The results provide new evidence that exposure to nicotine in pregnancy can cause fetal arrhythmia in various patterns besides tachycardia and bradycardia, the possible mechanisms for nicotine-induced fetal arrhythmia included in utero hypoxia. Importantly, following exposure to nicotine significantly increased risk of arrhythmia in the adult offspring. The finding offers new insight for development of cardiac rhythm problems in fetal origins.
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Affiliation(s)
- Yu Feng
- Perinatal Biology Center, Soochow University, Suzhou 213325, China
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20
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Abstract
Hypoxia-inducible factor (HIF) is an important transcriptional regulator of cell metabolism and the adaptation to cellular stress caused by oxygen deficiency (hypoxia). Phagocytic cells have an essential role in innate immune defence against pathogens and this is a battle that takes place mainly in the hypoxic microenvironments of infected tissues. It has now become clear that HIF promotes the bactericidal activities of phagocytic cells and supports the innate immune functions of dendritic cells, mast cells and epithelial cells. In response to microbial pathogens, HIF expression is upregulated through pathways involving the key immune response regulator nuclear factor-kappaB, highlighting an interdependence of the innate immune and hypoxic responses to infection and tissue damage. In turn, HIF-driven innate immune responses have important consequences for both the pathogen and the host, such that the tissue microenvironment fundamentally influences susceptibility to infectious disease.
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Monsarrat N, Houfflin-Debarge V, Richard A, Launay D, Lambert M, Hatron PY, Subtil D, Deruelle P. [Fetal ultrasonography and Doppler in isolated congenital heart block]. ACTA ACUST UNITED AC 2009; 37:633-44. [PMID: 19586792 DOI: 10.1016/j.gyobfe.2009.05.003] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2008] [Accepted: 05/18/2009] [Indexed: 12/23/2022]
Abstract
Isolated congenital heart block is linked to transplacental passage of maternal anti-SSA/Ro and/or anti-SSB/La antibodies that may be related to a connective tissue disease. Ultrasonography and Doppler are essential to screen fetus at risk. They allow the diagnosis of first- and second-degree blocks which are probably preliminary stages in conducting tissue's injury. In these situations, a maternal treatment by fluorinated steroids can be proposed because of its possible effect on partial blocks. However, these early signs of nodal injury can be lacking: some fetus present a complete heart block without previously detected less advanced block. Moreover, the significance of first-degree block is unclear since it could reverse spontaneously. Other markers of nodal injury would be valuable. In case of complete congenital heart block, ultrasonography is useful to detect congestive heart failure and help the obstetrical management when unfavorable prognostic signs occur.
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Affiliation(s)
- N Monsarrat
- Clinique d'obstétrique, hôpital Jeanne-de-Flandre, centre hospitalier régional et universitaire (CHRU) de Lille, avenue Eugène-Avinée, 59037 Lille cedex, France.
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Cardiac manifestations of neonatal lupus erythematosus: guidelines to management, integrating clues from the bench and bedside. Nat Rev Rheumatol 2009; 5:139-48. [PMID: 19252519 DOI: 10.1038/ncprheum1018] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2008] [Accepted: 01/05/2009] [Indexed: 12/25/2022]
Abstract
One of the strongest clinical associations with autoantibodies against components of the SSA/Ro-SSB/La ribonucleoprotein complex is the development of congenital heart block in an offspring, an alarming prospect facing 2% of primigravid mothers with these reactivities. This risk is increased tenfold in women who have had a previous child with congenital heart block. Accumulated evidence suggests that anti-SSA/Ro and anti-SSB/La antibodies are necessary but insufficient for fetal disease. Basic and clinical research is heavily focused on identifying fetal and environmental factors that convert disease susceptibility to disease development. A disturbing observation that has emerged from current research efforts is the rapidity of disease progression, with advanced heart block and life-threatening cardiomyopathy being observed less than 2 weeks after detection of a normal sinus rhythm. Once third-degree block is unequivocally identified, reversal has never been achieved, despite dexamethasone treatment. Accordingly, strategies aimed at preventing disease before irrevocable scarring ensues assume a high priority. One approach has been the implementation of serial echocardiography to monitor for a prolonged PR interval. Intravenous immunoglobulin is being evaluated as a potential prophylactic approach in mothers who have previously had an affected child.
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Buyon JP, Clancy RM, Friedman DM. Autoimmune associated congenital heart block: integration of clinical and research clues in the management of the maternal / foetal dyad at risk. J Intern Med 2009; 265:653-62. [PMID: 19493059 PMCID: PMC3551292 DOI: 10.1111/j.1365-2796.2009.02100.x] [Citation(s) in RCA: 101] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
One of the strongest associations with autoantibodies directed to components of the SSA/Ro-SSB/La ribonucleoprotein complex is the development of congenital heart block (CHB) in an offspring, an alarming prospect facing 2% of primigravid mothers with these reactivities. This risk is 10-fold higher in women who have had a previously affected child with CHB. Anti-Ro/La antibodies are necessary but insufficient to cause disease. In vitro and in vivo experiments suggest that the pathogenesis involves exaggerated apoptosis, macrophage/myfibroblast crosstalk, TGFbeta expression and extensive fibrosis in the conducting system and in some cases surrounding myocardium. A disturbing observation is the rapidity of disease progression, with advanced heart block and life-threatening cardiomyopathy observed <2 weeks from normal sinus rhythm. Once 3rd degree (complete) block is identified, reversal has never been achieved, despite dexamethasone. Current strategies include the evaluation of an early echocardiographic marker of injury, such as a prolonged PR interval and the use of IVIG as a preventative measure for pregnancies of mothers with previously affected children.
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Affiliation(s)
- J P Buyon
- Department of Medicine, New York University Langone School of Medicine, New York, 10016, USA.
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Cardiac fibroblasts: at the heart of myocardial remodeling. Pharmacol Ther 2009; 123:255-78. [PMID: 19460403 DOI: 10.1016/j.pharmthera.2009.05.002] [Citation(s) in RCA: 737] [Impact Index Per Article: 49.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2009] [Accepted: 05/05/2009] [Indexed: 12/24/2022]
Abstract
Cardiac fibroblasts are the most prevalent cell type in the heart and play a key role in regulating normal myocardial function and in the adverse myocardial remodeling that occurs with hypertension, myocardial infarction and heart failure. Many of the functional effects of cardiac fibroblasts are mediated through differentiation to a myofibroblast phenotype that expresses contractile proteins and exhibits increased migratory, proliferative and secretory properties. Cardiac myofibroblasts respond to proinflammatory cytokines (e.g. TNFalpha, IL-1, IL-6, TGF-beta), vasoactive peptides (e.g. angiotensin II, endothelin-1, natriuretic peptides) and hormones (e.g. noradrenaline), the levels of which are increased in the remodeling heart. Their function is also modulated by mechanical stretch and changes in oxygen availability (e.g. ischaemia-reperfusion). Myofibroblast responses to such stimuli include changes in cell proliferation, cell migration, extracellular matrix metabolism and secretion of various bioactive molecules including cytokines, vasoactive peptides and growth factors. Several classes of commonly prescribed therapeutic agents for cardiovascular disease also exert pleiotropic effects on cardiac fibroblasts that may explain some of their beneficial outcomes on the remodeling heart. These include drugs for reducing hypertension (ACE inhibitors, angiotensin receptor blockers, beta-blockers), cholesterol levels (statins, fibrates) and insulin resistance (thiazolidinediones). In this review, we provide insight into the properties of cardiac fibroblasts that underscores their importance in the remodeling heart, including their origin, electrophysiological properties, role in matrix metabolism, functional responses to environmental stimuli and ability to secrete bioactive molecules. We also review the evidence suggesting that certain cardiovascular drugs can reduce myocardial remodeling specifically via modulatory effects on cardiac fibroblasts.
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