1
|
Song Y, Yang C. Mechanistic advances of hyperoxia-induced immature brain injury. Heliyon 2024; 10:e30005. [PMID: 38694048 PMCID: PMC11058899 DOI: 10.1016/j.heliyon.2024.e30005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2023] [Revised: 04/11/2024] [Accepted: 04/18/2024] [Indexed: 05/03/2024] Open
Abstract
The impact of hyperoxia-induced brain injury in preterm infants is being increasingly investigated. However, the parameters and protocols used to study this condition in animal models lack consistency. Research is further hampered by the fact that hyperoxia exerts both direct and indirect effects on oligodendrocytes and neurons, with the precise underlying mechanisms remaining unclear. In this article, we aim to provide a comprehensive overview of the conditions used to induce hyperoxia in animal models of immature brain injury. We discuss what is known regarding the mechanisms underlying hyperoxia-induced immature brain injury, focusing on the effects on oligodendrocytes and neurons, and briefly describe therapies that may counteract the effects of hyperoxia. We also identify further studies required to fully elucidate the effects of hyperoxia on the immature brain as well as discuss the leading therapeutic options.
Collapse
Affiliation(s)
- Yue Song
- Department of Pediatrics, The First Affiliated Hospital of Chengdu Medical College, Chengdu 610500, Sichuan Province, China
- Department of Clinical Medicine, The Chengdu Medical College, Chengdu 610500, Sichuan Province, China
| | - Changqiang Yang
- Department of Cardiology, The First Affiliated Hospital of Chengdu Medical College, Chengdu 610500, Sichuan Province, China
- Department of Clinical Medicine, The Chengdu Medical College, Chengdu 610500, Sichuan Province, China
| |
Collapse
|
2
|
Xue-Jiao H, Jian-Hua F. A review of the effects of early postnatal hyperoxia exposure on the immature brain. Exp Neurol 2023; 370:114550. [PMID: 37774766 DOI: 10.1016/j.expneurol.2023.114550] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2023] [Revised: 09/17/2023] [Accepted: 09/25/2023] [Indexed: 10/01/2023]
Abstract
Preterm birth is a public health priority worldwide, with approximately 15 million premature babies born each year. Oxygen supplementation is one of the most common interventions for preterm infants. However, prolonged oxygen inhalation at supraphysiological concentrations can lead to the development of bronchopulmonary dysplasia (BPD). In addition to lifelong pulmonary sequelae, clinical evidence suggests that BPD is associated with adverse neurodevelopmental outcomes, such as motor impairment, cognitive impairment, and behavioral deficits, severely affecting the quality of life of preterm infants. However, the mechanisms underlying the combination of neurodevelopmental impairment with BPD remain unclear. Therefore, in recent years, attention has also been focused on the effects of hyperoxia on brain development in preterm infants. In this review, we outline the pathophysiological mechanisms of brain injury caused by developmental hyperoxia exposure in current animal models and briefly describe the pharmacological therapies that may be applicable to the associated brain injury. Overall, more studies are needed to assess the effects of hyperoxia on the immature brain, particularly combined analyses of the lungs and brain in the same experimental setting, to elucidate the potential causes of combined neurodevelopmental impairment in BPD.
Collapse
Affiliation(s)
- Huang Xue-Jiao
- Department of Pediatrics, Shengjing Hospital of China Medical University, Shenyang, China
| | - Fu Jian-Hua
- Department of Pediatrics, Shengjing Hospital of China Medical University, Shenyang, China.
| |
Collapse
|
3
|
Yang M, Shen Y, Zhao S, Zhang R, Dong W, Lei X. Protective effect of resveratrol on mitochondrial biogenesis during hyperoxia-induced brain injury in neonatal pups. BMC Neurosci 2023; 24:27. [PMID: 37098490 PMCID: PMC10127954 DOI: 10.1186/s12868-023-00797-1] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2022] [Accepted: 04/14/2023] [Indexed: 04/27/2023] Open
Abstract
BACKGROUND Neonatal hyperoxic brain injury is caused by exposure to hyperphysiological oxygen content during the period of incomplete development of the oxidative stress defence system, resulting in a large number of reactive oxygen species (ROS) and causing damage to brain tissue. Mitochondrial biogenesis refers to the synthesis of new mitochondria from existing mitochondria, mostly through the PGC-1α/Nrfs/TFAM signalling pathway. Resveratrol (Res), a silencing information regulator 2-related enzyme 1 (Sirt1) agonist, has been shown to upregulate the level of Sirt1 and the expression of peroxisome proliferator-activated receptor gamma coactivator-1α (PGC-1α). We speculate that Res has a protective effect on hyperoxia-induced brain injury through mitochondrial biogenesis. METHODS Sprague-Dawley (SD) pups were randomly divided into the nonhyperoxia (NN) group, the nonhyperoxia with dimethyl sulfoxide (ND) group, the nonhyperoxia with Res (NR) group, the hyperoxia (HN) group, the hyperoxia with dimethyl sulfoxide (HD) group, and the hyperoxia with Res (HR) group within 12 h after birth. The HN, HD, and HR groups were placed in a high-oxygen environment (80‒85%), and the other three groups were placed in the standard atmosphere. The NR and HR groups were given 60 mg/kg Res every day, the ND and HD groups were given the same dose of dimethyl sulfoxide (DMSO) every day, and the NN and HN groups were given the same dose of normal saline every day. On postnatal day (PN) 1, PN7, and PN14, brain samples were acquired for HE staining to assess pathology, TUNEL to detect apoptosis, and real-time quantitative polymerase chain reaction and immunoblotting to detect the expression levels of Sirt1, PGC-1α, nuclear respiratory factor 1 (Nrf1), nuclear respiratory factor 2 (Nrf2) and mitochondrial transcription factor A (TFAM) in brain tissue. RESULTS Hyperoxia induced brain tissue injury; increased brain tissue apoptosis; inhibited Sirt1, PGC-1α, Nrf1, Nrf2, TFAM mRNA expression in mitochondria; diminished the ND1 copy number and ND4/ND1 ratio; and decreased Sirt1, PGC-1α, Nrf1, Nrf2, and TFAM protein levels in the brain. In contrast, Res reduced brain injury and attenuated brain tissue apoptosis in neonatal pups and increased the levels of the corresponding indices. CONCLUSION Res has a protective effect on hyperoxia-induced brain injury in neonatal SD pups by upregulating Sirt1 and stimulating the PGC-1α/Nrfs/TFAM signalling pathway for mitochondrial biogenesis.
Collapse
Affiliation(s)
- Menghan Yang
- Division of Neonatology, Department of Pediatrics, The Affiliated Hospital of Southwest Medical University, No. 8, Section 2, Kangcheng Road, Luzhou, Sichuan, 646000, China
- Department of Perinatology, The Affiliated Hospital of Southwest Medical University, Luzhou, Sichuan, China
- Sichuan Clinical Research Center for Birth Defects, Luzhou, Sichuan, China
| | - Yunchuan Shen
- Division of Neonatology, Department of Pediatrics, The Affiliated Hospital of Southwest Medical University, No. 8, Section 2, Kangcheng Road, Luzhou, Sichuan, 646000, China
- Department of Perinatology, The Affiliated Hospital of Southwest Medical University, Luzhou, Sichuan, China
- Sichuan Clinical Research Center for Birth Defects, Luzhou, Sichuan, China
| | - Shuai Zhao
- Division of Neonatology, Department of Pediatrics, The Affiliated Hospital of Southwest Medical University, No. 8, Section 2, Kangcheng Road, Luzhou, Sichuan, 646000, China
- Department of Perinatology, The Affiliated Hospital of Southwest Medical University, Luzhou, Sichuan, China
- Sichuan Clinical Research Center for Birth Defects, Luzhou, Sichuan, China
| | - Rong Zhang
- Division of Neonatology, Department of Pediatrics, The Affiliated Hospital of Southwest Medical University, No. 8, Section 2, Kangcheng Road, Luzhou, Sichuan, 646000, China
- Department of Perinatology, The Affiliated Hospital of Southwest Medical University, Luzhou, Sichuan, China
- Sichuan Clinical Research Center for Birth Defects, Luzhou, Sichuan, China
| | - Wenbin Dong
- Division of Neonatology, Department of Pediatrics, The Affiliated Hospital of Southwest Medical University, No. 8, Section 2, Kangcheng Road, Luzhou, Sichuan, 646000, China.
- Department of Perinatology, The Affiliated Hospital of Southwest Medical University, Luzhou, Sichuan, China.
- Sichuan Clinical Research Center for Birth Defects, Luzhou, Sichuan, China.
| | - Xiaoping Lei
- Division of Neonatology, Department of Pediatrics, The Affiliated Hospital of Southwest Medical University, No. 8, Section 2, Kangcheng Road, Luzhou, Sichuan, 646000, China.
- Department of Perinatology, The Affiliated Hospital of Southwest Medical University, Luzhou, Sichuan, China.
- Sichuan Clinical Research Center for Birth Defects, Luzhou, Sichuan, China.
| |
Collapse
|
4
|
Mancardi D, Ottolenghi S, Attanasio U, Tocchetti CG, Paroni R, Pagliaro P, Samaja M. Janus, or the Inevitable Battle Between Too Much and Too Little Oxygen. Antioxid Redox Signal 2022; 37:972-989. [PMID: 35412859 DOI: 10.1089/ars.2021.0232] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Significance: Oxygen levels are key regulators of virtually every living mammalian cell, under both physiological and pathological conditions. Starting from embryonic and fetal development, through the growth, onset, and progression of diseases, oxygen is a subtle, although pivotal, mediator of key processes such as differentiation, proliferation, autophagy, necrosis, and apoptosis. Hypoxia-driven modifications of cellular physiology are investigated in depth or for their clinical and translational relevance, especially in the ischemic scenario. Recent Advances: The mild or severe lack of oxygen is, undoubtedly, related to cell death, although abundant evidence points at oscillating oxygen levels, instead of permanent low pO2, as the most detrimental factor. Different cell types can consume oxygen at different rates and, most interestingly, some cells can shift from low to high consumption according to the metabolic demand. Hence, we can assume that, in the intracellular compartment, oxygen tension varies from low to high levels depending on both supply and consumption. Critical Issues: The positive balance between supply and consumption leads to a pro-oxidative environment, with some cell types facing hypoxia/hyperoxia cycles, whereas some others are under fairly constant oxygen tension. Future Directions: Within this frame, the alterations of oxygen levels (dysoxia) are critical in two paradigmatic organs, the heart and brain, under physiological and pathological conditions and the interactions of oxygen with other physiologically relevant gases, such as nitric oxide, can alternatively contribute to the worsening or protection of ischemic organs. Further, the effects of dysoxia are of pivotal importance for iron metabolism. Antioxid. Redox Signal. 37, 972-989.
Collapse
Affiliation(s)
- Daniele Mancardi
- Department of Clinical and Biological Sciences, University of Torino, Turin, Italy
| | - Sara Ottolenghi
- Department of Health Sciences, University of Milano, Milan, Italy
- School of Medicine and Surgery, University of Milano Bicocca, Milan, Italy
| | - Umberto Attanasio
- Cardio-Oncology Unit, Department of Translational Medical Sciences, Federico II University, Naples, Italy
| | - Carlo Gabriele Tocchetti
- Cardio-Oncology Unit, Department of Translational Medical Sciences, Federico II University, Naples, Italy
- Interdepartmental Center for Clinical and Translational Research (CIRCET), Federico II University, Naples, Italy
- Interdepartmental Hypertension Research Center (CIRIAPA), Federico II University, Naples, Italy
- Center for Basic and Clinical Immunology Research (CISI), Federico II University, Naples, Italy
| | - Rita Paroni
- Department of Health Sciences, University of Milano, Milan, Italy
| | - Pasquale Pagliaro
- Department of Clinical and Biological Sciences, University of Torino, Turin, Italy
| | - Michele Samaja
- Department of Health Sciences, University of Milano, Milan, Italy
- MAGI GROUP, San Felice del Benaco, Italy
| |
Collapse
|
5
|
Chaudhari P, Madaan A, Rivera JC, Charfi I, Habelrih T, Hou X, Nezhady M, Lodygensky G, Pineyro G, Muanza T, Chemtob S. Neuronal GPR81 regulates developmental brain angiogenesis and promotes brain recovery after a hypoxic ischemic insult. J Cereb Blood Flow Metab 2022; 42:1294-1308. [PMID: 35107038 PMCID: PMC9207492 DOI: 10.1177/0271678x221077499] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Perinatal hypoxic/ischemic (HI) brain injury is a major clinical problem with devastating neurodevelopmental outcomes in neonates. During HI brain injury, dysregulated factor production contributes to microvascular impairment. Glycolysis-derived lactate accumulated during ischemia has been proposed to protect against ischemic injury, but its mechanism of action is poorly understood. Herein, we hypothesize that lactate via its G-protein coupled receptor (GPR81) controls postnatal brain angiogenesis and plays a protective role after HI injury. We show that GPR81 is predominantly expressed in neurons of the cerebral cortex and hippocampus. GPR81-null mice displayed a delay in cerebral microvascular development linked to reduced levels of various major angiogenic factors and augmented expression of anti-angiogenic Thrombospondin-1 (TSP-1) in comparison to their WT littermates. Coherently, lactate stimulation induced an increase in growth factors (VEGF, Ang1 and 2, PDGF) and reduced TSP-1 expression in neurons, which contributed to accelerating angiogenesis. HI injury in GPR81-null animals curtailed vascular density and consequently increased infarct size compared to changes seen in WT mice; conversely intracerebroventricular lactate injection increased vascular density and diminished infarct size in WT but not in GPR81-null mice. Collectively, we show that lactate acting via GPR81 participates in developmental brain angiogenesis, and attenuates HI injury by restoring compromised microvasculature.
Collapse
Affiliation(s)
- Prabhas Chaudhari
- Departments of Pediatrics, Ophthalmology and Pharmacology, CHU Sainte-Justine Research Center, Montréal, Canada.,Department of Experimental Medicine, McGill University, Montréal, Canada
| | - Ankush Madaan
- Departments of Pediatrics, Ophthalmology and Pharmacology, CHU Sainte-Justine Research Center, Montréal, Canada.,Department of Pharmacology, McGill University, Montréal, Canada
| | - José Carlos Rivera
- Departments of Pediatrics, Ophthalmology and Pharmacology, CHU Sainte-Justine Research Center, Montréal, Canada.,Department of Opthalmology, Université de Montréal, Montréal, Canada.,Maisonneuve-Rosemont Hospital, Research Center, Montréal, Canada
| | - Iness Charfi
- Department of Experimental Medicine, McGill University, Montréal, Canada.,Department of Pharmacology, McGill University, Montréal, Canada
| | - Tiffany Habelrih
- Departments of Pediatrics, Ophthalmology and Pharmacology, CHU Sainte-Justine Research Center, Montréal, Canada
| | - Xin Hou
- Departments of Pediatrics, Ophthalmology and Pharmacology, CHU Sainte-Justine Research Center, Montréal, Canada
| | - Mohammad Nezhady
- Departments of Pediatrics, Ophthalmology and Pharmacology, CHU Sainte-Justine Research Center, Montréal, Canada
| | - Gregory Lodygensky
- Departments of Pediatrics, Ophthalmology and Pharmacology, CHU Sainte-Justine Research Center, Montréal, Canada
| | - Graciela Pineyro
- Departments of Pediatrics, Ophthalmology and Pharmacology, CHU Sainte-Justine Research Center, Montréal, Canada.,Department of Experimental Medicine, McGill University, Montréal, Canada.,Department of Pharmacology, McGill University, Montréal, Canada
| | - Thierry Muanza
- Department of Experimental Medicine, McGill University, Montréal, Canada
| | - Sylvain Chemtob
- Departments of Pediatrics, Ophthalmology and Pharmacology, CHU Sainte-Justine Research Center, Montréal, Canada.,Department of Pharmacology, McGill University, Montréal, Canada.,Department of Opthalmology, Université de Montréal, Montréal, Canada.,Maisonneuve-Rosemont Hospital, Research Center, Montréal, Canada
| |
Collapse
|
6
|
Perinatal Hyperoxia and Developmental Consequences on the Lung-Brain Axis. OXIDATIVE MEDICINE AND CELLULAR LONGEVITY 2022; 2022:5784146. [PMID: 35251477 PMCID: PMC8894035 DOI: 10.1155/2022/5784146] [Citation(s) in RCA: 20] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/25/2021] [Accepted: 01/04/2022] [Indexed: 12/12/2022]
Abstract
Approximately 11.1% of all newborns worldwide are born preterm. Improved neonatal intensive care significantly increased survival rates over the last decades but failed to reduce the risk for the development of chronic lung disease (i.e., bronchopulmonary dysplasia (BPD)) and impaired neurodevelopment (i.e., encephalopathy of prematurity (EoP)), two major long-term sequelae of prematurity. Premature infants are exposed to relative hyperoxia, when compared to physiological in-utero conditions and, if needed to additional therapeutic oxygen supplementation. Both are associated with an increased risk for impaired organ development. Since the detrimental effects of hyperoxia on the immature retina are known for many years, lung and brain have come into focus in the last decade. Hyperoxia-induced excessive production of reactive oxygen species leading to oxidative stress and inflammation contribute to pulmonary growth restriction and abnormal neurodevelopment, including myelination deficits. Despite a large body of studies, which unraveled important pathophysiological mechanisms for both organs at risk, the majority focused exclusively either on lung or on brain injury. However, considering that preterm infants suffering from BPD are at higher risk for poor neurodevelopmental outcome, an interaction between both organs seems plausible. This review summarizes recent findings regarding mechanisms of hyperoxia-induced neonatal lung and brain injury. We will discuss common pathophysiological pathways, which potentially link both injured organ systems. Furthermore, promises and needs of currently suggested therapies, including pharmacological and regenerative cell-based treatments for BPD and EoP, will be emphasized. Limited therapeutic approaches highlight the urgent need for a better understanding of the mechanisms underlying detrimental effects of hyperoxia on the lung-brain axis in order to pave the way for the development of novel multimodal therapies, ideally targeting both severe preterm birth-associated complications.
Collapse
|
7
|
Coler BS, Shynlova O, Boros-Rausch A, Lye S, McCartney S, Leimert KB, Xu W, Chemtob S, Olson D, Li M, Huebner E, Curtin A, Kachikis A, Savitsky L, Paul JW, Smith R, Adams Waldorf KM. Landscape of Preterm Birth Therapeutics and a Path Forward. J Clin Med 2021; 10:2912. [PMID: 34209869 PMCID: PMC8268657 DOI: 10.3390/jcm10132912] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2021] [Revised: 06/24/2021] [Accepted: 06/28/2021] [Indexed: 12/24/2022] Open
Abstract
Preterm birth (PTB) remains the leading cause of infant morbidity and mortality. Despite 50 years of research, therapeutic options are limited and many lack clear efficacy. Tocolytic agents are drugs that briefly delay PTB, typically to allow antenatal corticosteroid administration for accelerating fetal lung maturity or to transfer patients to high-level care facilities. Globally, there is an unmet need for better tocolytic agents, particularly in low- and middle-income countries. Although most tocolytics, such as betamimetics and indomethacin, suppress downstream mediators of the parturition pathway, newer therapeutics are being designed to selectively target inflammatory checkpoints with the goal of providing broader and more effective tocolysis. However, the relatively small market for new PTB therapeutics and formidable regulatory hurdles have led to minimal pharmaceutical interest and a stagnant drug pipeline. In this review, we present the current landscape of PTB therapeutics, assessing the history of drug development, mechanisms of action, adverse effects, and the updated literature on drug efficacy. We also review the regulatory hurdles and other obstacles impairing novel tocolytic development. Ultimately, we present possible steps to expedite drug development and meet the growing need for effective preterm birth therapeutics.
Collapse
Affiliation(s)
- Brahm Seymour Coler
- Department of Obstetrics and Gynecology, University of Washington, Seattle, WA 98195, USA; (B.S.C.); (S.M.); (M.L.); (E.H.); (A.C.); (A.K.); (L.S.)
- Elson S. Floyd College of Medicine, Washington State University, Spokane, WA 99202, USA
| | - Oksana Shynlova
- Department of Physiology, University of Toronto, Toronto, ON M5S 1A8, Canada; (O.S.); (A.B.-R.); (S.L.)
- Department of Obstetrics and Gynecology, University of Toronto, Toronto, ON M5G 1E2, Canada
| | - Adam Boros-Rausch
- Department of Physiology, University of Toronto, Toronto, ON M5S 1A8, Canada; (O.S.); (A.B.-R.); (S.L.)
| | - Stephen Lye
- Department of Physiology, University of Toronto, Toronto, ON M5S 1A8, Canada; (O.S.); (A.B.-R.); (S.L.)
- Department of Obstetrics and Gynecology, University of Toronto, Toronto, ON M5G 1E2, Canada
| | - Stephen McCartney
- Department of Obstetrics and Gynecology, University of Washington, Seattle, WA 98195, USA; (B.S.C.); (S.M.); (M.L.); (E.H.); (A.C.); (A.K.); (L.S.)
| | - Kelycia B. Leimert
- Department of Obstetrics and Gynecology, University of Alberta, Edmonton, AB T6G 2R7, Canada; (K.B.L.); (W.X.); (D.O.)
| | - Wendy Xu
- Department of Obstetrics and Gynecology, University of Alberta, Edmonton, AB T6G 2R7, Canada; (K.B.L.); (W.X.); (D.O.)
| | - Sylvain Chemtob
- Departments of Pediatrics, Université de Montréal, Montréal, QC H3T 1J4, Canada;
| | - David Olson
- Department of Obstetrics and Gynecology, University of Alberta, Edmonton, AB T6G 2R7, Canada; (K.B.L.); (W.X.); (D.O.)
- Departments of Pediatrics and Physiology, University of Alberta, Edmonton, AB T6G 2S2, Canada
| | - Miranda Li
- Department of Obstetrics and Gynecology, University of Washington, Seattle, WA 98195, USA; (B.S.C.); (S.M.); (M.L.); (E.H.); (A.C.); (A.K.); (L.S.)
- Department of Biological Sciencies, Columbia University, New York, NY 10027, USA
| | - Emily Huebner
- Department of Obstetrics and Gynecology, University of Washington, Seattle, WA 98195, USA; (B.S.C.); (S.M.); (M.L.); (E.H.); (A.C.); (A.K.); (L.S.)
| | - Anna Curtin
- Department of Obstetrics and Gynecology, University of Washington, Seattle, WA 98195, USA; (B.S.C.); (S.M.); (M.L.); (E.H.); (A.C.); (A.K.); (L.S.)
| | - Alisa Kachikis
- Department of Obstetrics and Gynecology, University of Washington, Seattle, WA 98195, USA; (B.S.C.); (S.M.); (M.L.); (E.H.); (A.C.); (A.K.); (L.S.)
| | - Leah Savitsky
- Department of Obstetrics and Gynecology, University of Washington, Seattle, WA 98195, USA; (B.S.C.); (S.M.); (M.L.); (E.H.); (A.C.); (A.K.); (L.S.)
| | - Jonathan W. Paul
- Mothers and Babies Research Centre, School of Medicine and Public Health, College of Health, Medicine and Wellbeing, University of Newcastle, Callaghan, NSW 2308, Australia; (J.W.P.); (R.S.)
- Hunter Medical Research Institute, 1 Kookaburra Circuit, New Lambton Heights, NSW 2305, Australia
| | - Roger Smith
- Mothers and Babies Research Centre, School of Medicine and Public Health, College of Health, Medicine and Wellbeing, University of Newcastle, Callaghan, NSW 2308, Australia; (J.W.P.); (R.S.)
- Hunter Medical Research Institute, 1 Kookaburra Circuit, New Lambton Heights, NSW 2305, Australia
- John Hunter Hospital, New Lambton Heights, NSW 2305, Australia
| | - Kristina M. Adams Waldorf
- Department of Obstetrics and Gynecology, University of Washington, Seattle, WA 98195, USA; (B.S.C.); (S.M.); (M.L.); (E.H.); (A.C.); (A.K.); (L.S.)
- Department of Global Health, University of Washington, Seattle, WA 98195, USA
| |
Collapse
|
8
|
Chudnovets A, Lei J, Na Q, Dong J, Narasimhan H, Klein SL, Burd I. Dose-dependent structural and immunological changes in the placenta and fetal brain in response to systemic inflammation during pregnancy. Am J Reprod Immunol 2020; 84:e13248. [PMID: 32306461 DOI: 10.1111/aji.13248] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2019] [Revised: 03/22/2020] [Accepted: 04/10/2020] [Indexed: 12/12/2022] Open
Abstract
PROBLEM Systemic maternal inflammation is associated with adverse neonatal sequelae. We tested the hypothesis that IL-1β is a key inflammatory regulator of adverse pregnancy outcomes. METHOD OF STUDY Pregnant mice were treated with intraperitoneal injections of IL-1β (0, 0.1, 0.5, or 1 μg) from embryonic day (E)14 to E17. Placenta and fetal brains were harvested and analyzed for morphologic changes and IL-1β signaling markers. RESULTS As compared with non-treated dams, maternal injections with IL-1β resulted in increased p-NF-κB and caspase-1 in placentas and fetal brains, but not consistently in spleens, suggesting induction of intrinsic IL-1β production. These findings were confirmed by increased levels of IL-1β in the placentas of the IL-1β-treated dams. Systemic treatment of dams with IL-1β suppressed Stat1 signaling. Maternal inflammation caused by IL-1β treatment reduced fetal viability to 80.6% and 58.9%, in dams treated with either 0.5 or 1 μg of IL-1β, respectively. In the placentas, there was an IL-1β dose-dependent distortion of the labyrinth structure, decreased numbers of mononuclear trophoblast giant cells, and reduced proportions of endothelial cells as compared to placentas from control dams. In fetal brains collected at E17, there was an IL-1β dose-dependent reduction in cortical neuronal morphology. CONCLUSION This work demonstrates that systemic IL-1β injection causes dose-dependent structural and functional changes in the placenta and fetal brain.
Collapse
Affiliation(s)
- Anna Chudnovets
- Integrated Research Center for Fetal Medicine, Department of Gynecology and Obstetrics, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Jun Lei
- Integrated Research Center for Fetal Medicine, Department of Gynecology and Obstetrics, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Quan Na
- Integrated Research Center for Fetal Medicine, Department of Gynecology and Obstetrics, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Jie Dong
- Integrated Research Center for Fetal Medicine, Department of Gynecology and Obstetrics, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Harish Narasimhan
- W. Harry Feinstone Department of Molecular Microbiology and Immunology, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, USA
| | - Sabra L Klein
- W. Harry Feinstone Department of Molecular Microbiology and Immunology, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, USA
| | - Irina Burd
- Integrated Research Center for Fetal Medicine, Department of Gynecology and Obstetrics, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| |
Collapse
|
9
|
Morris-Schaffer K, Sobolewski M, Allen JL, Marvin E, Yee M, Arora M, O'Reilly MA, Cory-Slechta DA. Effect of neonatal hyperoxia followed by concentrated ambient ultrafine particle exposure on cumulative learning in C57Bl/6J mice. Neurotoxicology 2018; 67:234-244. [PMID: 29920326 DOI: 10.1016/j.neuro.2018.06.006] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2018] [Revised: 06/11/2018] [Accepted: 06/12/2018] [Indexed: 01/01/2023]
Abstract
Hyperoxia during treatment for prematurity may enhance susceptibility to other risk factors for adverse brain development, such as air pollution exposure, as both of these risk factors have been linked to a variety of adverse neurodevelopmental outcomes. This study investigated the combined effects of neonatal hyperoxia followed by inhalation of concentrated ambient ultrafine particles (CAPS, <100 nm in aerodynamic diameter) on learning. C57BL/6 J mice were birthed into 60% oxygen until postnatal day (PND) 4 and subsequently exposed to filtered air or to CAPS using the Harvard University Concentrated Ambient Particle System (HUCAPS) from PND 4-7 and 10-13. Behavior was assessed on a fixed interval (FI) schedule of reinforcement in which reward is available only after a fixed interval of time elapses, as well as expected reductions in behavior during an extinction procedure when reward was withheld. Both produce highly comparable behavioral performance across species. Performance measures included rate of responding, response accuracy, and temporal control (quarter life). Exposure to hyperoxia or CAPS resulted in lower mean quarter life values, an effect that was further enhanced in males by combined exposure, findings consistent with delayed learning of the FI schedule. Females also initially exhibited greater reductions in quarter life values following the combined exposure to hyperoxia and CAPS and delayed reductions in response rates during extinction. Combined hyperoxia and CAPS produced greater learning deficits than either risk factor alone, consistent with enhanced neurodevelopmental toxicity, findings that could reflect a convergence of both insults on common neurobiological systems. The basis for sex differences in outcome warrants further research. This study highlights the potential for heightened risk of adverse neurodevelopment outcomes in individuals born preterm in regions with higher levels of ultrafine particle (UFP) air pollution, in accord with the multiplicity of risk factors extant in the human environment.
Collapse
Affiliation(s)
- Keith Morris-Schaffer
- Department of Environmental Medicine, University of Rochester Medical Center, Rochester NY 14642, United States
| | - Marissa Sobolewski
- Department of Environmental Medicine, University of Rochester Medical Center, Rochester NY 14642, United States
| | - Joshua L Allen
- Department of Environmental Medicine, University of Rochester Medical Center, Rochester NY 14642, United States
| | - Elena Marvin
- Department of Environmental Medicine, University of Rochester Medical Center, Rochester NY 14642, United States
| | - Min Yee
- Department of Pediatrics, University of Rochester Medical Center, Rochester NY, 14642, United States
| | - Manish Arora
- Department of Environmental Medicine and Public Health, Icahn School of Medicine at Mount Sinai, New York, NY 10029, United States
| | - Michael A O'Reilly
- Department of Pediatrics, University of Rochester Medical Center, Rochester NY, 14642, United States
| | - Deborah A Cory-Slechta
- Department of Environmental Medicine, University of Rochester Medical Center, Rochester NY 14642, United States.
| |
Collapse
|
10
|
Terraneo L, Samaja M. Comparative Response of Brain to Chronic Hypoxia and Hyperoxia. Int J Mol Sci 2017; 18:ijms18091914. [PMID: 28880206 PMCID: PMC5618563 DOI: 10.3390/ijms18091914] [Citation(s) in RCA: 49] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2017] [Revised: 09/01/2017] [Accepted: 09/03/2017] [Indexed: 12/25/2022] Open
Abstract
Two antithetic terms, hypoxia and hyperoxia, i.e., insufficient and excess oxygen availability with respect to needs, are thought to trigger opposite responses in cells and tissues. This review aims at summarizing the molecular and cellular mechanisms underlying hypoxia and hyperoxia in brain and cerebral tissue, a context that may prove to be useful for characterizing not only several clinically relevant aspects, but also aspects related to the evolution of oxygen transport and use by the tissues. While the response to acute hypoxia/hyperoxia presumably recruits only a minor portion of the potentially involved cell machinery, focusing into chronic conditions, instead, enables to take into consideration a wider range of potential responses to oxygen-linked stress, spanning from metabolic to genic. We will examine how various brain subsystems, including energetic metabolism, oxygen sensing, recruitment of pro-survival pathways as protein kinase B (Akt), mitogen-activated protein kinases (MAPK), neurotrophins (BDNF), erythropoietin (Epo) and its receptors (EpoR), neuroglobin (Ngb), nitric oxide (NO), carbon monoxide (CO), deal with chronic hypoxia and hyperoxia to end-up with the final outcomes, oxidative stress and brain damage. A more complex than expected pattern results, which emphasizes the delicate balance between the severity of the stress imposed by hypoxia and hyperoxia and the recruitment of molecular and cellular defense patterns. While for certain functions the expectation that hypoxia and hyperoxia should cause opposite responses is actually met, for others it is not, and both emerge as dangerous treatments.
Collapse
Affiliation(s)
- Laura Terraneo
- Department of Health Science, University of Milan, I-20142 Milano, Italy.
| | - Michele Samaja
- Department of Health Science, University of Milan, I-20142 Milano, Italy.
| |
Collapse
|
11
|
Bulboacă AE, Bolboacă SD, Bulboacă AC, Prodan CI. Association between low thyroid-stimulating hormone, posterior cortical atrophy and nitro-oxidative stress in elderly patients with cognitive dysfunction. Arch Med Sci 2017; 13:1160-1167. [PMID: 28883858 PMCID: PMC5575209 DOI: 10.5114/aoms.2016.60129] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/12/2015] [Accepted: 04/22/2016] [Indexed: 01/14/2023] Open
Abstract
INTRODUCTION Cortical atrophy is known to be a valuable sign of cognitive decline. The purpose of this study was to assess the association between low thyroid-stimulating hormone (TSH), posterior cortical atrophy (Koedam score - KS) and nitro-oxidative stress in elderly patients. MATERIAL AND METHODS A study (SG) and a control group (CG), each subdivided by gender, were investigated. Subjects older than 59 years with low serum TSH level and with mild cognitive impairment were included in the SG. The CG was formed by subjects free of significant cortical atrophy and free or thyroid dysfunction. Demographic and clinical characteristics of the patients (Mini Mental State Examination, MMSE), Koedam score on cranial magnetic resonance imaging, and blood parameters (TSH, FT4, and nitric oxide - NOx) were assessed. RESULTS Subjects in the study group had fewer years of education above the 8th grade compared with the control group (p < 0.0001). A significantly higher percentage of subjects in the study group had a Koedam score of 2 or 3 compared with controls, who had in the majority of cases a Koedam score of zero (p < 0.02). Significantly higher NOx levels were observed when study groups of both genders were compared with corresponding controls (p < 0.001). No significant differences were observed with regard to FT4 (p > 0.70). Nitric oxide was found to be significantly associated with TSH (p < 0.03) and KS (p < 0.002) when the whole study group was considered as well as when just the non-smoker study group was investigated. CONCLUSIONS Our study revealed an association between subclinical thyroid hypofunction, nitro-oxidative stress, and posterior cortical atrophy as an early stage of global atrophy.
Collapse
Affiliation(s)
- Adriana E. Bulboacă
- Department of Pathophysiology, Iuliu Haţieganu University of Medicine and Pharmacy, Cluj-Napoca, Romania
| | - Sorana D. Bolboacă
- Department of Medical Informatics and Biostatistics, Iuliu Haţieganu University of Medicine and Pharmacy, Cluj-Napoca, Romania
| | - Angelo C. Bulboacă
- Department of Neurology, Iuliu Haţieganu University of Medicine and Pharmacy, Cluj-Napoca, Romania
| | - Călin I. Prodan
- Department of Neurology, The University of Oklahoma Health Sciences Center & VA Medical Center, Oklahoma City, OK, USA
| |
Collapse
|
12
|
Nadeau-Vallée M, Chin PY, Belarbi L, Brien MÈ, Pundir S, Berryer MH, Beaudry-Richard A, Madaan A, Sharkey DJ, Lupien-Meilleur A, Hou X, Quiniou C, Beaulac A, Boufaied I, Boudreault A, Carbonaro A, Doan ND, Joyal JS, Lubell WD, Olson DM, Robertson SA, Girard S, Chemtob S. Antenatal Suppression of IL-1 Protects against Inflammation-Induced Fetal Injury and Improves Neonatal and Developmental Outcomes in Mice. THE JOURNAL OF IMMUNOLOGY 2017; 198:2047-2062. [PMID: 28148737 DOI: 10.4049/jimmunol.1601600] [Citation(s) in RCA: 80] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/14/2016] [Accepted: 12/30/2016] [Indexed: 01/08/2023]
Abstract
Preterm birth (PTB) is commonly accompanied by in utero fetal inflammation, and existing tocolytic drugs do not target fetal inflammatory injury. Of the candidate proinflammatory mediators, IL-1 appears central and is sufficient to trigger fetal loss. Therefore, we elucidated the effects of antenatal IL-1 exposure on postnatal development and investigated two IL-1 receptor antagonists, the competitive inhibitor anakinra (Kineret) and a potent noncompetitive inhibitor 101.10, for efficacy in blocking IL-1 actions. Antenatal exposure to IL-1β induced Tnfa, Il6, Ccl2, Pghs2, and Mpges1 expression in placenta and fetal membranes, and it elevated amniotic fluid IL-1β, IL-6, IL-8, and PGF2α, resulting in PTB and marked neonatal mortality. Surviving neonates had increased Il1b, Il6, Il8, Il10, Pghs2, Tnfa, and Crp expression in WBCs, elevated plasma levels of IL-1β, IL-6, and IL-8, increased IL-1β, IL-6, and IL-8 in fetal lung, intestine, and brain, and morphological abnormalities: e.g., disrupted lung alveolarization, atrophy of intestinal villus and colon-resident lymphoid follicle, and degeneration and atrophy of brain microvasculature with visual evoked potential anomalies. Late gestation treatment with 101.10 abolished these adverse outcomes, whereas Kineret exerted only modest effects and no benefit for gestation length, neonatal mortality, or placental inflammation. In a LPS-induced model of infection-associated PTB, 101.10 prevented PTB, neonatal mortality, and fetal brain inflammation. There was no substantive deviation in postnatal growth trajectory or adult body morphometry after antenatal 101.10 treatment. The results implicate IL-1 as an important driver of neonatal morbidity in PTB and identify 101.10 as a safe and effective candidate therapeutic.
Collapse
Affiliation(s)
- Mathieu Nadeau-Vallée
- Department of Pediatrics, CHU Sainte-Justine Research Center, Montreal, Quebec H3T 1C5, Canada.,Department of Ophthalmology, CHU Sainte-Justine Research Center, Montreal, Quebec H3T 1C5, Canada.,Department of Pharmacology, CHU Sainte-Justine Research Center, Montreal, Quebec H3T 1C5, Canada.,Department of Pharmacology, University of Montreal, Montreal, Quebec H3T 1J4, Canada
| | - Peck-Yin Chin
- Department of Obstetrics and Gynecology, Adelaide Medical School and Robinson Research Institute, University of Adelaide, Adelaide, South Australia 5005, Australia
| | - Lydia Belarbi
- Department of Pediatrics, CHU Sainte-Justine Research Center, Montreal, Quebec H3T 1C5, Canada.,Department of Ophthalmology, CHU Sainte-Justine Research Center, Montreal, Quebec H3T 1C5, Canada.,Department of Pharmacology, CHU Sainte-Justine Research Center, Montreal, Quebec H3T 1C5, Canada
| | - Marie-Ève Brien
- Department of Obstetrics and Gynecology, University of Montreal, CHU Sainte-Justine Research Center, Montreal, Quebec H3T 1J4, Canada.,Department of Microbiology, Infectiology, and Immunology, University of Montreal, CHU Sainte-Justine Research Center, Montreal, Quebec H3T 1J4, Canada
| | - Sheetal Pundir
- Department of Pediatrics, CHU Sainte-Justine Research Center, Montreal, Quebec H3T 1C5, Canada.,Department of Ophthalmology, CHU Sainte-Justine Research Center, Montreal, Quebec H3T 1C5, Canada.,Department of Pharmacology, CHU Sainte-Justine Research Center, Montreal, Quebec H3T 1C5, Canada.,Department of Pharmacology and Therapeutics, McGill University, Montreal, Quebec H3G 1Y6, Canada
| | - Martin H Berryer
- Department of Neurosciences, CHU Sainte-Justine Research Center, University of Montreal, Montreal, Quebec H3T 1J4, Canada
| | - Alexandra Beaudry-Richard
- Department of Pediatrics, CHU Sainte-Justine Research Center, Montreal, Quebec H3T 1C5, Canada.,Department of Ophthalmology, CHU Sainte-Justine Research Center, Montreal, Quebec H3T 1C5, Canada.,Department of Pharmacology, CHU Sainte-Justine Research Center, Montreal, Quebec H3T 1C5, Canada
| | - Ankush Madaan
- Department of Pediatrics, CHU Sainte-Justine Research Center, Montreal, Quebec H3T 1C5, Canada.,Department of Ophthalmology, CHU Sainte-Justine Research Center, Montreal, Quebec H3T 1C5, Canada.,Department of Pharmacology, CHU Sainte-Justine Research Center, Montreal, Quebec H3T 1C5, Canada.,Department of Pharmacology and Therapeutics, McGill University, Montreal, Quebec H3G 1Y6, Canada
| | - David J Sharkey
- Department of Obstetrics and Gynecology, Adelaide Medical School and Robinson Research Institute, University of Adelaide, Adelaide, South Australia 5005, Australia
| | - Alexis Lupien-Meilleur
- Department of Neurosciences, CHU Sainte-Justine Research Center, University of Montreal, Montreal, Quebec H3T 1J4, Canada
| | - Xin Hou
- Department of Pediatrics, CHU Sainte-Justine Research Center, Montreal, Quebec H3T 1C5, Canada.,Department of Ophthalmology, CHU Sainte-Justine Research Center, Montreal, Quebec H3T 1C5, Canada.,Department of Pharmacology, CHU Sainte-Justine Research Center, Montreal, Quebec H3T 1C5, Canada
| | - Christiane Quiniou
- Department of Pediatrics, CHU Sainte-Justine Research Center, Montreal, Quebec H3T 1C5, Canada.,Department of Ophthalmology, CHU Sainte-Justine Research Center, Montreal, Quebec H3T 1C5, Canada.,Department of Pharmacology, CHU Sainte-Justine Research Center, Montreal, Quebec H3T 1C5, Canada
| | - Alexandre Beaulac
- Department of Pediatrics, CHU Sainte-Justine Research Center, Montreal, Quebec H3T 1C5, Canada.,Department of Ophthalmology, CHU Sainte-Justine Research Center, Montreal, Quebec H3T 1C5, Canada.,Department of Pharmacology, CHU Sainte-Justine Research Center, Montreal, Quebec H3T 1C5, Canada
| | - Ines Boufaied
- Department of Obstetrics and Gynecology, University of Montreal, CHU Sainte-Justine Research Center, Montreal, Quebec H3T 1J4, Canada.,Department of Microbiology, Infectiology, and Immunology, University of Montreal, CHU Sainte-Justine Research Center, Montreal, Quebec H3T 1J4, Canada
| | - Amarilys Boudreault
- Department of Pediatrics, CHU Sainte-Justine Research Center, Montreal, Quebec H3T 1C5, Canada.,Department of Ophthalmology, CHU Sainte-Justine Research Center, Montreal, Quebec H3T 1C5, Canada.,Department of Pharmacology, CHU Sainte-Justine Research Center, Montreal, Quebec H3T 1C5, Canada
| | - Adriana Carbonaro
- Department of Obstetrics and Gynecology, University of Montreal, CHU Sainte-Justine Research Center, Montreal, Quebec H3T 1J4, Canada.,Department of Microbiology, Infectiology, and Immunology, University of Montreal, CHU Sainte-Justine Research Center, Montreal, Quebec H3T 1J4, Canada
| | - Ngoc-Duc Doan
- Department of Chemistry, University of Montreal, Montreal, Quebec H3T 1J4, Canada
| | - Jean-Sebastien Joyal
- Department of Pediatrics, CHU Sainte-Justine Research Center, Montreal, Quebec H3T 1C5, Canada.,Department of Ophthalmology, CHU Sainte-Justine Research Center, Montreal, Quebec H3T 1C5, Canada.,Department of Pharmacology, CHU Sainte-Justine Research Center, Montreal, Quebec H3T 1C5, Canada.,Department of Pharmacology, University of Montreal, Montreal, Quebec H3T 1J4, Canada
| | - William D Lubell
- Department of Chemistry, University of Montreal, Montreal, Quebec H3T 1J4, Canada
| | - David M Olson
- Department of Obstetrics and Gynecology, University of Alberta, Edmonton, Alberta T6G 2R3, Canada.,Department of Pediatrics, University of Alberta, Edmonton, Alberta T6G 2R3, Canada; and.,Department of Physiology, University of Alberta, Edmonton, Alberta T6G 2R3, Canada
| | - Sarah A Robertson
- Department of Obstetrics and Gynecology, Adelaide Medical School and Robinson Research Institute, University of Adelaide, Adelaide, South Australia 5005, Australia;
| | - Sylvie Girard
- Department of Obstetrics and Gynecology, University of Montreal, CHU Sainte-Justine Research Center, Montreal, Quebec H3T 1J4, Canada; .,Department of Microbiology, Infectiology, and Immunology, University of Montreal, CHU Sainte-Justine Research Center, Montreal, Quebec H3T 1J4, Canada
| | - Sylvain Chemtob
- Department of Pediatrics, CHU Sainte-Justine Research Center, Montreal, Quebec H3T 1C5, Canada; .,Department of Ophthalmology, CHU Sainte-Justine Research Center, Montreal, Quebec H3T 1C5, Canada.,Department of Pharmacology, CHU Sainte-Justine Research Center, Montreal, Quebec H3T 1C5, Canada.,Department of Pharmacology, University of Montreal, Montreal, Quebec H3T 1J4, Canada.,Department of Pharmacology and Therapeutics, McGill University, Montreal, Quebec H3G 1Y6, Canada
| |
Collapse
|
13
|
Fletcher E, Wade J, Georgala PA, Gillespie TL, Price DJ, Pilley E, Becher JC. Oxygen flux reduces Cux1 positive neurons and cortical growth in a gestational rodent model of growth restriction. Ann Anat 2016; 210:84-93. [PMID: 27986613 DOI: 10.1016/j.aanat.2016.11.014] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2015] [Revised: 08/18/2016] [Accepted: 11/04/2016] [Indexed: 12/17/2022]
Abstract
BACKGROUND The mammalian cerebral cortex forms in an inside-out manner, establishing deep cortical layers before superficial layers and is regulated by transcription factors which influence cell differentiation. Preterm birth interrupts the trajectory of normal neurodevelopment and adverse perinatal exposures have been implicated in cortical injury. We hypothesise that growth restriction (GR) and fluctuating hyperoxia (ΔO2) impair cortical laminar development. METHODS Sprague-Dawley rats received 18% (non-restricted, NR) or 9% (growth restricted, GR) protein diet from E15-P7. Litters were reared in air or fluctuating hyperoxia (circa 10kPa) from P0 to P7. Cortical laminae were stained and measured. Neuronal subtypes were quantified using immunofluorescence for subtype-specific transcription factors (Satb2, Cux1, Ctip2, Tbr1). RESULTS ΔO2 did not affect brain weight at P7 but reduced cortical thickness in both NR (p<0.05) and GR groups (p<0.001). ΔO2 resulted in superficial cortical thinning in both groups and in the deep layers of GR pups (p<0.001). Cell density was preserved. ΔO2 did not affect proportions of callosal, corticothalamic and corticospinal neurons but resulted in a reduction of neurons expressing Cux1 (p<0.01) implicated in dendritic branching and synapse formation. CONCLUSION Postnatal ΔO2, a modifiable factor in neonatal care, impairs cortical development in a rodent model with preferential disadvantage to superficial neurons.
Collapse
Affiliation(s)
- Elaine Fletcher
- Jennifer Brown Research Laboratory, Centre for Reproductive Health, Queen's Medical Research Institute, University of Edinburgh, 47 Little France Crescent, Edinburgh, Scotland, EH16 4TJ, UK.
| | - Jean Wade
- Jennifer Brown Research Laboratory, Centre for Reproductive Health, Queen's Medical Research Institute, University of Edinburgh, 47 Little France Crescent, Edinburgh, Scotland, EH16 4TJ, UK
| | - Petrina A Georgala
- Centre of Integrative Physiology, Hugh Robson Building, University of Edinburgh, George Square, Edinburgh, Scotland, EH8 9XD, UK
| | - Trudi L Gillespie
- Centre for Inflammation Research, Queens Medical Research Institute, University of Edinburgh, 47 Little France Crescent, Edinburgh, Scotland, EH16 4TJ, UK
| | - David J Price
- Centre of Integrative Physiology, Hugh Robson Building, University of Edinburgh, George Square, Edinburgh, Scotland, EH8 9XD, UK
| | - Elizabeth Pilley
- Jennifer Brown Research Laboratory, Centre for Reproductive Health, Queen's Medical Research Institute, University of Edinburgh, 47 Little France Crescent, Edinburgh, Scotland, EH16 4TJ, UK
| | - Julie-Clare Becher
- Jennifer Brown Research Laboratory, Centre for Reproductive Health, Queen's Medical Research Institute, University of Edinburgh, 47 Little France Crescent, Edinburgh, Scotland, EH16 4TJ, UK
| |
Collapse
|
14
|
Intratracheal transplantation of mesenchymal stem cells simultaneously attenuates both lung and brain injuries in hyperoxic newborn rats. Pediatr Res 2016; 80:415-24. [PMID: 27064241 DOI: 10.1038/pr.2016.88] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/30/2015] [Accepted: 02/20/2016] [Indexed: 12/24/2022]
Abstract
BACKGROUND Bronchopulmonary dysplasia is an independent risk factor for adverse neurodevelopmental outcomes in premature infants. We investigated whether attenuation of hyperoxic lung injury with intratracheal transplantation of human umbilical cord blood-derived mesenchymal stem cells (MSCs) could simultaneously mitigate brain damage in neonatal rats. METHODS Newborn Sprague-Dawley rats were exposed to hyperoxia or normoxia conditions for 14 d. MSCs (5 × 10(5) cells) were transplanted intratracheally at postnatal day (P) 5. At P14, lungs and brains were harvested for histological and biochemical analyses. RESULTS Hyperoxic lung injuries, such as impaired alveolarization evident from increased mean linear intercept (MLI) and elevated inflammatory cytokine levels were significantly alleviated with MSC transplantation. Hyperoxia decreased brain weight, increased brain cell death, and induced hypomyelination. MSC transplantation significantly ameliorated hyperoxia-induced increased terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL)-positive cells in the dentate gyrus and reduced myelin basic protein. In correlation analyses, brain weight and myelin basic protein (MBP) were significantly inversely correlated with lung MLI and inflammatory cytokines, while TUNEL-positive brain cell number showed a significant positive correlation with lung MLI. CONCLUSION Despite no significant improvement in short-term neurofunctional outcome, intratracheal transplantation of MSCs simultaneously attenuated hyperoxic lung and brain injuries in neonatal rats, with the extent of such attenuation being closely linked in the two tissues.
Collapse
|
15
|
Erythropoietin Restores Long-Term Neurocognitive Function Involving Mechanisms of Neuronal Plasticity in a Model of Hyperoxia-Induced Preterm Brain Injury. OXIDATIVE MEDICINE AND CELLULAR LONGEVITY 2016; 2016:9247493. [PMID: 27493706 PMCID: PMC4963567 DOI: 10.1155/2016/9247493] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/22/2016] [Revised: 05/31/2016] [Accepted: 06/13/2016] [Indexed: 12/22/2022]
Abstract
Cerebral white and grey matter injury is the leading cause of an adverse neurodevelopmental outcome in prematurely born infants. High oxygen concentrations have been shown to contribute to the pathogenesis of neonatal brain damage. Here, we focused on motor-cognitive outcome up to the adolescent and adult age in an experimental model of preterm brain injury. In search of the putative mechanisms of action we evaluated oligodendrocyte degeneration, myelination, and modulation of synaptic plasticity-related molecules. A single dose of erythropoietin (20,000 IU/kg) at the onset of hyperoxia (24 hours, 80% oxygen) in 6-day-old Wistar rats improved long-lasting neurocognitive development up to the adolescent and adult stage. Analysis of white matter structures revealed a reduction of acute oligodendrocyte degeneration. However, erythropoietin did not influence hypomyelination occurring a few days after injury or long-term microstructural white matter abnormalities detected in adult animals. Erythropoietin administration reverted hyperoxia-induced reduction of neuronal plasticity-related mRNA expression up to four months after injury. Thus, our findings highlight the importance of erythropoietin as a neuroregenerative treatment option in neonatal brain injury, leading to improved memory function in adolescent and adult rats which may be linked to increased neuronal network connectivity.
Collapse
|
16
|
Poon AWH, Ma EXH, Vadivel A, Jung S, Khoja Z, Stephens L, Thébaud B, Wintermark P. Impact of bronchopulmonary dysplasia on brain and retina. Biol Open 2016; 5:475-83. [PMID: 26988760 PMCID: PMC4890677 DOI: 10.1242/bio.017665] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
Many premature newborns develop bronchopulmonary dysplasia (BPD), a chronic lung disease resulting from prolonged mechanical ventilation and hyperoxia. BPD survivors typically suffer long-term injuries not only to the lungs, but also to the brain and retina. However, currently it is not clear whether the brain and retinal injuries in these newborns are related only to their prematurity, or also to BPD. We investigated whether the hyperoxia known to cause histologic changes in the lungs similar to BPD in an animal model also causes brain and retinal injuries. Sprague Dawley rat pups were exposed to hyperoxia (95% O2, ‘BPD’ group) or room air (21% O2, ‘control’ group) from postnatal day 4–14 (P4–14); the rat pups were housed in room air between P14 and P28. At P28, they were sacrificed, and their lungs, brain, and eyes were extracted. Hematoxylin and eosin staining was performed on lung and brain sections; retinas were stained with Toluidine Blue. Hyperoxia exposure resulted in an increased mean linear intercept in the lungs (P<0.0001). This increase was associated with a decrease in some brain structures [especially the whole-brain surface (P=0.02)], as well as a decrease in the thickness of the retinal layers [especially the total retina (P=0.0008)], compared to the room air control group. In addition, a significant negative relationship was observed between the lung structures and the brain (r=−0.49, P=0.02) and retina (r=−0.70, P=0.0008) structures. In conclusion, hyperoxia exposure impaired lung, brain, and retina structures. More severe lung injuries correlated with more severe brain and retinal injuries. This result suggests that the same animal model of chronic neonatal hyperoxia can be used to simultaneously study lung, brain and retinal injuries related to hyperoxia. Summary: Our results suggest that the same animal model of chronic neonatal hyperoxia can be used to simultaneously study lung, brain and retinal injuries related to hyperoxia.
Collapse
Affiliation(s)
- Annie Wing Hoi Poon
- Division of Newborn Medicine, Department of Pediatrics, McGill University, Montreal, Quebec H4A 3J1, Canada
| | - Emilie Xiao Hang Ma
- Division of Newborn Medicine, Department of Pediatrics, McGill University, Montreal, Quebec H4A 3J1, Canada
| | - Arul Vadivel
- Ottawa Hospital Research Institute, Regenerative Medicine Program, Department of Pediatrics, Children's Hospital of Eastern Ontario, University of Ottawa, Ottawa, Ontario K1H 8L6, Canada
| | - Suna Jung
- Division of Newborn Medicine, Department of Pediatrics, McGill University, Montreal, Quebec H4A 3J1, Canada
| | - Zehra Khoja
- Division of Newborn Medicine, Department of Pediatrics, McGill University, Montreal, Quebec H4A 3J1, Canada
| | - Laurel Stephens
- Division of Newborn Medicine, Department of Pediatrics, McGill University, Montreal, Quebec H4A 3J1, Canada
| | - Bernard Thébaud
- Ottawa Hospital Research Institute, Regenerative Medicine Program, Department of Pediatrics, Children's Hospital of Eastern Ontario, University of Ottawa, Ottawa, Ontario K1H 8L6, Canada
| | - Pia Wintermark
- Division of Newborn Medicine, Department of Pediatrics, McGill University, Montreal, Quebec H4A 3J1, Canada
| |
Collapse
|
17
|
Serdar M, Herz J, Kempe K, Lumpe K, Reinboth BS, Sizonenko SV, Hou X, Herrmann R, Hadamitzky M, Heumann R, Hansen W, Sifringer M, van de Looij Y, Felderhoff-Müser U, Bendix I. Fingolimod protects against neonatal white matter damage and long-term cognitive deficits caused by hyperoxia. Brain Behav Immun 2016; 52:106-119. [PMID: 26456693 DOI: 10.1016/j.bbi.2015.10.004] [Citation(s) in RCA: 57] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/27/2015] [Revised: 09/26/2015] [Accepted: 10/03/2015] [Indexed: 11/29/2022] Open
Abstract
Cerebral white matter injury is a leading cause of adverse neurodevelopmental outcome in prematurely born infants involving cognitive deficits in later life. Despite increasing knowledge about the pathophysiology of perinatal brain injury, therapeutic options are limited. In the adult demyelinating disease multiple sclerosis the sphingosine-1-phosphate (S1P) receptor modulating substance fingolimod (FTY720) has beneficial effects. Herein, we evaluated the neuroprotective potential of FTY720 in a neonatal model of oxygen-toxicity, which is associated with hypomyelination and impaired neuro-cognitive outcome. A single dose of FTY720 (1mg/kg) at the onset of neonatal hyperoxia (24h 80% oxygen on postnatal day 6) resulted in improvement of neuro-cognitive development persisting into adulthood. This was associated with reduced microstructural white matter abnormalities 4 months after the insult. In search of the underlying mechanisms potential non-classical (i.e. lymphocyte-independent) pathways were analysed shortly after the insult, comprising modulation of oxidative stress and local inflammatory responses as well as myelination, oligodendrocyte degeneration and maturation. Treatment with FTY720 reduced hyperoxia-induced oxidative stress, microglia activation and associated pro-inflammatory cytokine expression. In vivo and in vitro analyses further revealed that oxygen-induced hypomyelination is restored to control levels, which was accompanied by reduced oligodendrocyte degeneration and enhanced maturation. Furthermore, hyperoxia-induced elevation of S1P receptor 1 (S1P1) protein expression on in vitro cultured oligodendrocyte precursor cells was reduced by activated FTY720 and protection from degeneration is abrogated after selective S1P1 blockade. Finally, FTY720s' classical mode of action (i.e. retention of immune cells within peripheral lymphoid organs) was analysed demonstrating that FTY720 diminished circulating lymphocyte counts independent from hyperoxia. Cerebral immune cell counts remained unchanged by hyperoxia and by FTY720 treatment. Taken together, these results suggest that beneficial effects of FTY720 in neonatal oxygen-induced brain injury may be rather attributed to its anti-oxidative and anti-inflammatory capacity acting in concert with a direct protection of developing oligodendrocytes than to a modulation of peripheral lymphocyte trafficking. Thus, FTY720 might be a potential new therapeutic option for the treatment of neonatal brain injury through reduction of white matter damage.
Collapse
Affiliation(s)
- Meray Serdar
- Department of Pediatrics 1 - Neonatology, University Hospital Essen, University Duisburg-Essen, Essen, Germany
| | - Josephine Herz
- Department of Pediatrics 1 - Neonatology, University Hospital Essen, University Duisburg-Essen, Essen, Germany
| | - Karina Kempe
- Department of Pediatrics 1 - Neonatology, University Hospital Essen, University Duisburg-Essen, Essen, Germany
| | - Katharina Lumpe
- Department of Pediatrics 1 - Neonatology, University Hospital Essen, University Duisburg-Essen, Essen, Germany
| | - Barbara S Reinboth
- Department of Pediatrics 1 - Neonatology, University Hospital Essen, University Duisburg-Essen, Essen, Germany
| | | | - Xinlin Hou
- Department of Pediatrics 1 - Neonatology, University Hospital Essen, University Duisburg-Essen, Essen, Germany
| | - Ralf Herrmann
- Department of Pediatrics 1 - Neonatology, University Hospital Essen, University Duisburg-Essen, Essen, Germany
| | - Martin Hadamitzky
- Institute of Medical Psychology and Behavioral Immunobiology, University Hospital Essen, University Duisburg-Essen, Essen, Germany
| | - Rolf Heumann
- Molecular Neurochemistry, Faculty of Chemistry and Biochemistry, Ruhr University Bochum, Bochum, Germany
| | - Wiebke Hansen
- Institute of Medical Microbiology, University Hospital Essen, University Duisburg-Essen, Essen, Germany
| | - Marco Sifringer
- Department of Anesthesiology and Intensive Care Medicine, Charité-Universitätsmedizin Berlin, Berlin, Germany
| | - Yohan van de Looij
- Department of Pediatrics, University of Geneva, Genève, Switzerland; Laboratory of Functional and Metabolic Imaging, Ecole Polytechnique Fédérale de Lausanne, Lausanne, Switzerland
| | - Ursula Felderhoff-Müser
- Department of Pediatrics 1 - Neonatology, University Hospital Essen, University Duisburg-Essen, Essen, Germany.
| | - Ivo Bendix
- Department of Pediatrics 1 - Neonatology, University Hospital Essen, University Duisburg-Essen, Essen, Germany.
| |
Collapse
|
18
|
Abdelsaid M, Prakash R, Li W, Coucha M, Hafez S, Johnson MH, Fagan SC, Ergul A. Metformin treatment in the period after stroke prevents nitrative stress and restores angiogenic signaling in the brain in diabetes. Diabetes 2015; 64:1804-17. [PMID: 25524911 PMCID: PMC4407857 DOI: 10.2337/db14-1423] [Citation(s) in RCA: 59] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/15/2014] [Accepted: 12/11/2014] [Indexed: 12/04/2022]
Abstract
Diabetes impedes vascular repair and causes vasoregression in the brain after stroke, but mechanisms underlying this response are still unclear. We hypothesized that excess peroxynitrite formation in diabetic ischemia/reperfusion (I/R) injury inactivates the p85 subunit of phosphoinositide 3-kinase (PI3K) by nitration and diverts the PI3K-Akt survival signal to the p38-mitogen-activated protein kinase apoptosis pathway. Nitrotyrosine (NY), Akt and p38 activity, p85 nitration, and caspase-3 cleavage were measured in brains from control, diabetic (GK), or metformin-treated GK rats subjected to sham or stroke surgery and in brain microvascular endothelial cells (BMVECs) from Wistar and GK rats subjected to hypoxia/reoxygenation injury. GK rat brains showed increased NY, caspase-3 cleavage, and p38 activation and decreased Akt activation. Metformin attenuated stroke-induced nitrative signaling in GK rats. GK rat BMVECs showed increased basal nitrative stress compared with controls. A second hit by hypoxia/reoxygenation injury dramatically increased the nitration of p85 and activation of p38 but decreased Akt. These effects were associated with impairment of angiogenic response and were restored by treatment with the peroxynitrite scavenger 5,10,15,20-tetrakis(4-sulfonatophenyl)porphyrinato iron III chloride or the nitration inhibitor epicatechin. Our results provide evidence that I/R-induced peroxynitrite inhibits survival, induces apoptosis, and promotes peroxynitrite as a novel therapeutic target for the improvement of reparative angiogenesis after stroke in diabetes.
Collapse
Affiliation(s)
- Mohammed Abdelsaid
- Charlie Norwood Veterans Administration Medical Center, Augusta, GA Department of Physiology, Georgia Regents University, Augusta, GA
| | - Roshini Prakash
- Program in Clinical and Experimental Therapeutics, University of Georgia College of Pharmacy, Augusta, GA
| | - Weiguo Li
- Charlie Norwood Veterans Administration Medical Center, Augusta, GA Department of Physiology, Georgia Regents University, Augusta, GA
| | - Maha Coucha
- Department of Physiology, Georgia Regents University, Augusta, GA
| | - Sherif Hafez
- Charlie Norwood Veterans Administration Medical Center, Augusta, GA Program in Clinical and Experimental Therapeutics, University of Georgia College of Pharmacy, Augusta, GA
| | | | - Susan C Fagan
- Charlie Norwood Veterans Administration Medical Center, Augusta, GA Program in Clinical and Experimental Therapeutics, University of Georgia College of Pharmacy, Augusta, GA
| | - Adviye Ergul
- Charlie Norwood Veterans Administration Medical Center, Augusta, GA Department of Physiology, Georgia Regents University, Augusta, GA Program in Clinical and Experimental Therapeutics, University of Georgia College of Pharmacy, Augusta, GA
| |
Collapse
|
19
|
Joyal JS, Nim S, Zhu T, Sitaras N, Rivera JC, Shao Z, Sapieha P, Hamel D, Sanchez M, Zaniolo K, St-Louis M, Ouellette J, Montoya-Zavala M, Zabeida A, Picard E, Hardy P, Bhosle V, Varma DR, Gobeil F, Beauséjour C, Boileau C, Klein W, Hollenberg M, Ribeiro-da-Silva A, Andelfinger G, Chemtob S. Subcellular localization of coagulation factor II receptor-like 1 in neurons governs angiogenesis. Nat Med 2014; 20:1165-73. [PMID: 25216639 DOI: 10.1038/nm.3669] [Citation(s) in RCA: 54] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2014] [Accepted: 07/23/2014] [Indexed: 02/07/2023]
Abstract
Neurons have an important role in retinal vascular development. Here we show that the G protein-coupled receptor (GPCR) coagulation factor II receptor-like 1 (F2rl1, previously known as Par2) is abundant in retinal ganglion cells and is associated with new blood vessel formation during retinal development and in ischemic retinopathy. After stimulation, F2rl1 in retinal ganglion cells translocates from the plasma membrane to the cell nucleus using a microtubule-dependent shuttle that requires sorting nexin 11 (Snx11). At the nucleus, F2rl1 facilitates recruitment of the transcription factor Sp1 to trigger Vegfa expression and, in turn, neovascularization. In contrast, classical plasma membrane activation of F2rl1 leads to the expression of distinct genes, including Ang1, that are involved in vessel maturation. Mutant versions of F2rl1 that prevent nuclear relocalization but not plasma membrane activation interfere with Vegfa but not Ang1 expression. Complementary angiogenic factors are therefore regulated by the subcellular localization of a receptor (F2rl1) that governs angiogenesis. These findings may have implications for the selectivity of drug actions based on the subcellular distribution of their targets.
Collapse
Affiliation(s)
- Jean-Sébastien Joyal
- 1] Department of Pediatrics, Centre Hospitalier Universitaire (CHU) Sainte-Justine Research Center, Université de Montréal, Montréal, Québec, Canada. [2] Department of Ophthalmology, Hôpital Maisonneuve-Rosemont Research Center, Université de Montreal, Montreal, Québec, Canada. [3] Department of Pharmacology, Université de Montréal, Montréal, Québec, Canada. [4] Department of Pharmacology and Therapeutics, McGill University, Montréal, Québec, Canada. [5]
| | - Satra Nim
- 1] Department of Pharmacology and Therapeutics, McGill University, Montréal, Québec, Canada. [2]
| | - Tang Zhu
- 1] Department of Pediatrics, Centre Hospitalier Universitaire (CHU) Sainte-Justine Research Center, Université de Montréal, Montréal, Québec, Canada. [2]
| | - Nicholas Sitaras
- 1] Department of Ophthalmology, Hôpital Maisonneuve-Rosemont Research Center, Université de Montreal, Montreal, Québec, Canada. [2] Department of Pharmacology, Université de Montréal, Montréal, Québec, Canada
| | - José Carlos Rivera
- 1] Department of Pediatrics, Centre Hospitalier Universitaire (CHU) Sainte-Justine Research Center, Université de Montréal, Montréal, Québec, Canada. [2] Department of Ophthalmology, Hôpital Maisonneuve-Rosemont Research Center, Université de Montreal, Montreal, Québec, Canada
| | - Zhuo Shao
- Department of Pharmacology and Therapeutics, McGill University, Montréal, Québec, Canada
| | - Przemyslaw Sapieha
- Department of Ophthalmology, Hôpital Maisonneuve-Rosemont Research Center, Université de Montreal, Montreal, Québec, Canada
| | - David Hamel
- Department of Pharmacology, Université de Montréal, Montréal, Québec, Canada
| | - Melanie Sanchez
- Department of Pharmacology and Therapeutics, McGill University, Montréal, Québec, Canada
| | - Karine Zaniolo
- Department of Pediatrics, Centre Hospitalier Universitaire (CHU) Sainte-Justine Research Center, Université de Montréal, Montréal, Québec, Canada
| | - Manon St-Louis
- Department of Pharmacology and Therapeutics, McGill University, Montréal, Québec, Canada
| | - Johanne Ouellette
- Department of Pharmacology and Therapeutics, McGill University, Montréal, Québec, Canada
| | | | - Alexandra Zabeida
- Department of Pediatrics, Centre Hospitalier Universitaire (CHU) Sainte-Justine Research Center, Université de Montréal, Montréal, Québec, Canada
| | - Emilie Picard
- Department of Pediatrics, Centre Hospitalier Universitaire (CHU) Sainte-Justine Research Center, Université de Montréal, Montréal, Québec, Canada
| | - Pierre Hardy
- Department of Pediatrics, Centre Hospitalier Universitaire (CHU) Sainte-Justine Research Center, Université de Montréal, Montréal, Québec, Canada
| | - Vikrant Bhosle
- Department of Pharmacology and Therapeutics, McGill University, Montréal, Québec, Canada
| | - Daya R Varma
- Department of Pharmacology and Therapeutics, McGill University, Montréal, Québec, Canada
| | - Fernand Gobeil
- Department of Pharmacology, Sherbrooke University, Sherbrooke, Quebec, Canada
| | | | - Christelle Boileau
- Department of Pharmacology, Université de Montréal, Montréal, Québec, Canada
| | - William Klein
- Department of Systems Biology, University of Texas MD Anderson Cancer Center, Houston, Texas, USA
| | - Morley Hollenberg
- Department of Physiology and Pharmacology, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada
| | | | - Gregor Andelfinger
- Department of Cardiology, CHU Sainte-Justine Research Center, Université de Montréal, Montréal, Québec, Canada
| | - Sylvain Chemtob
- 1] Department of Pediatrics, Centre Hospitalier Universitaire (CHU) Sainte-Justine Research Center, Université de Montréal, Montréal, Québec, Canada. [2] Department of Ophthalmology, Hôpital Maisonneuve-Rosemont Research Center, Université de Montreal, Montreal, Québec, Canada. [3] Department of Pharmacology, Université de Montréal, Montréal, Québec, Canada. [4] Department of Pharmacology and Therapeutics, McGill University, Montréal, Québec, Canada
| |
Collapse
|
20
|
Derivation of traceable and transplantable photoreceptors from mouse embryonic stem cells. Stem Cell Reports 2014; 2:853-65. [PMID: 24936471 PMCID: PMC4050344 DOI: 10.1016/j.stemcr.2014.04.010] [Citation(s) in RCA: 81] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2013] [Revised: 04/15/2014] [Accepted: 04/16/2014] [Indexed: 01/12/2023] Open
Abstract
Retinal degenerative diseases resulting in the loss of photoreceptors are one of the major causes of blindness. Photoreceptor replacement therapy is a promising treatment because the transplantation of retina-derived photoreceptors can be applied now to different murine retinopathies to restore visual function. To have an unlimited source of photoreceptors, we derived a transgenic embryonic stem cell (ESC) line in which the Crx-GFP transgene is expressed in photoreceptors and assessed the capacity of a 3D culture protocol to produce integration-competent photoreceptors. This culture system allows the production of a large number of photoreceptors recapitulating the in vivo development. After transplantation, integrated cells showed the typical morphology of mature rods bearing external segments and ribbon synapses. We conclude that a 3D protocol coupled with ESCs provides a safe and renewable source of photoreceptors displaying a development and transplantation competence comparable to photoreceptors from age-matched retinas. De novo isolation of Crx-GFP embryonic stem cell lines to trace photoreceptors 3D culture system fine-tuning to generate many integration-competent photoreceptors Revealing in-vitro- and in-vivo-developing retina similarities Characterization of the most appropriate stage to transplant photoreceptors
Collapse
|
21
|
Hsu YC, Chang YC, Lin YC, Sze CI, Huang CC, Ho CJ. Cerebral microvascular damage occurs early after hypoxia-ischemia via nNOS activation in the neonatal brain. J Cereb Blood Flow Metab 2014; 34:668-76. [PMID: 24398931 PMCID: PMC3982088 DOI: 10.1038/jcbfm.2013.244] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/13/2013] [Accepted: 12/16/2013] [Indexed: 11/09/2022]
Abstract
Microvascular injury early after hypoxic ischemia (HI) may contribute to neonatal brain damage. N-methyl-D-aspartate receptor overstimulation activates neuronal nitric oxide synthases (nNOS). We hypothesized that microvascular damage occurs early post-HI via nNOS activation and contributes to brain injury. Postpartum day-7 rat pups were treated with 7-nitroindazole (7-NI) or aminoguanidine (AG) before or after HI. Electron microscopy was performed to measure neuronal and endothelial cell damage. There were vascular lumen narrowing at 1 hour, pyknotic neurons at 3 hours, and extensive neuronal damage and loss of vessels at 24 hours post HI. Early after reoxygenation, there were neurons with heterochromatic chromatin and endothelial cells with enlarged nuclei occluding the lumen. There was also increased 3-nitrotyrosin in the microvessels and decreased cerebral blood perfusion. 7-NI and AG treatment before hypoxia provided complete and partial neuroprotection, respectively. Early post-reoxygenation, the AG group showed significantly increased microvascular nitrosative stress, microvascular interruptions, swollen nuclei that narrowed the vascular lumen, and decreased cerebral perfusion. The 7-NI group showed significantly decreased microvascular nitrosative stress, patent vascular lumen, and increased cerebral perfusion. Our results indicate that microvascular damage occurs early and progressively post HI. Neuronal nitric oxide synthases activation contributes to microvascular damage and decreased cerebral perfusion early after reoxygenation and worsens brain damage.
Collapse
Affiliation(s)
- Yi-Ching Hsu
- Institute of Basic Medical Sciences, National Cheng Kung University Medical College, Tainan City, Taiwan
| | - Ying-Chao Chang
- Department of Pediatrics, Chang Gung Kaohsiung Medical Center, Chang Gung University College of Medicine, Kaohsiung City, Taiwan
| | - Yung-Chieh Lin
- 1] Institute of Clinical Medicine, National Cheng Kung University Medical College, Tainan City, Taiwan [2] Department of Pediatrics, National Cheng Kung University Hospital, Tainan City, Taiwan
| | - Chun-I Sze
- Institute of Cell Biology and Anatomy, National Cheng Kung University Medical College, Tainan City, Taiwan
| | - Chao-Ching Huang
- 1] Department of Pediatrics, National Cheng Kung University Hospital, Tainan City, Taiwan [2] Department of Pediatrics, Taipei Medical University, College of Medicine, Taipei, Taiwan
| | - Chien-Jung Ho
- Department of Pediatrics, National Cheng Kung University Hospital, Tainan City, Taiwan
| |
Collapse
|
22
|
Mehdi MKIM, Sage-Ciocca D, Challet E, Malan A, Hicks D. Oxygen-induced retinopathy induces short-term glial stress and long-term impairment of photoentrainment in mice. Graefes Arch Clin Exp Ophthalmol 2014; 252:595-608. [PMID: 24509649 DOI: 10.1007/s00417-014-2579-5] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2013] [Revised: 01/14/2014] [Accepted: 01/16/2014] [Indexed: 10/25/2022] Open
Abstract
BACKGROUND Retinopathy of prematurity is a serious potentially blinding disease of pre-term infants. There is extensive vascular remodeling and tissue stress, but data concerning alterations in retinal neurons and glia, and long-term functional sequelae are still incomplete. METHODS ROP was induced using the oxygen-induced retinopathy (OIR) mouse model. Postnatal day 7 (P7) 129SVE mice were exposed to hyperoxia (75 ± 0.5 % oxygen) for 5 days, and then returned to normoxia to induce OIR. Exposed animals were euthanized at 5 (P17-OIR) and 14 days (P26-OIR) after return to normal air, together with corresponding age-matched control mice (P17-C and P26-C respectively) raised only in room air. Their retinas were examined by immunohistochemistry using a battery of antibodies against key glial and neuronal proteins. A further group of OIR mice and controls were examined at 10 weeks of age for their ability to re-entrain to changing 12 h light/12 h dark cycles, assayed by wheel-running actimetry. In this protocol, animals were subjected to three successive conditions of 300 lux, 15 lux and 1 lux ambient light intensity coupled with 6 hours of jetlag. Animals were euthanized at 4 months of age and used in immunoblotting for rhodopsin. RESULTS Compared to P17-C, immunohistochemical staining of P17-OIR sections showed up-regulation of stress-related and glutamate-regulatory proteins in astrocytes and Müller glial cells. In contrast, glial phenotypic expression in P26-OIR retinas largely resembled that in P26-C. There was no loss in total retinal ganglion cells (RGC) at either P17-OIR or P26-OIR compared to corresponding controls, whereas intrinsically photosensitive RGC showed significant decreases, with 375 ± 13/field in P26-OIR compared to 443 ± 30/field in P26-C (p < 0.05). Wheel actimetry performed on control and OIR-treated mice at 4 months demonstrated that animals raised in hyperoxic conditions had impaired photoentrainment at low illuminance of 1 lux, as well as significantly reduced levels of rhodopsin compared to age-matched controls. CONCLUSIONS OIR leads to transient up-regulation of retinal glial proteins involved in metabolism, and partial degeneration of intrinsically photosensitive RGC and rod photoreceptors. OIR affects circadian photo-entrainment at low illuminance values, possibly by affecting the rod pathway and/or intrinsically photosensitive RGC input to the circadian clock. This study hence shows that retinopathy of prematurity affects light-regulated circadian behavior in an animal model, and may induce similar problems in humans.
Collapse
Affiliation(s)
- Madah Khawn-I-Muhammad Mehdi
- Département de Neurobiologie des Rythmes, Institut des Neurosciences Cellulaires et Intégratives, CNRS UPR 3212 Université de Strasbourg, 5 rue Blaise Pascal, 67084, Strasbourg, Cedex, France
| | | | | | | | | |
Collapse
|
23
|
Imaging of an inflammatory injury in the newborn rat brain with photoacoustic tomography. PLoS One 2013; 8:e83045. [PMID: 24386140 PMCID: PMC3873292 DOI: 10.1371/journal.pone.0083045] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2013] [Accepted: 11/06/2013] [Indexed: 12/29/2022] Open
Abstract
Background The precise assessment of cerebral saturation changes during an inflammatory injury in the developing brain, such as seen in periventricular leukomalacia, is not well defined. This study investigated the impact of inflammation on locoregional cerebral oxygen saturation in a newborn rodent model using photoacoustic imaging. Methods 1 mg/kg of lipopolysaccharide(LPS) diluted in saline or saline alone was injected under ultrasound guidance directly in the corpus callosum of P3 rat pups. Coronal photoacoustic images were carried out 24 h after LPS exposure. Locoregional oxygen saturation (SO2) and resting state connectivity were assessed in the cortex and the corpus callosum. Microvasculature was then evaluated on cryosection slices by lectin histochemistry. Results Significant reduction of SO2 was found in the corpus callosum; reduced SO2 was also found in the cortex ipsilateral to the injection site. Seed-based functional connectivity analysis showed that bilateral connectivity was not affected by LPS exposure. Changes in locoregional oxygen saturation were accompanied by a significant reduction in the average length of microvessels in the left cortex but no differences were observed in the corpus callosum. Conclusion Inflammation in the developing brain induces marked reduction of locoregional oxygen saturation, predominantly in the white matter not explained by microvascular degeneration. The ability to examine regional saturation offers a new way to monitor injury and understand physiological disturbance non-invasively.
Collapse
|
24
|
Morken TS, Nyman AKG, Sandvig I, Torp SH, Skranes J, Goa PE, Brubakk AM, Widerøe M. Brain development after neonatal intermittent hyperoxia-hypoxia in the rat studied by longitudinal MRI and immunohistochemistry. PLoS One 2013; 8:e84109. [PMID: 24358332 PMCID: PMC3866165 DOI: 10.1371/journal.pone.0084109] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2013] [Accepted: 11/12/2013] [Indexed: 01/19/2023] Open
Abstract
BACKGROUND Neonatal intermittent hyperoxia-hypoxia (IHH) is involved in the pathogenesis of retinopathy of prematurity. Whether similar oxygen fluctuations will create pathological changes in the grey and white matter of the brain is unknown. METHODS From birth until postnatal day 14 (P14), two litters (total n = 22) were reared in IHH: hyperoxia (50% O2) interrupted by three consecutive two-minute episodes of hypoxia (12% O2) every sixth hour. Controls (n = 8) were reared in room-air (20.9% O2). Longitudinal MRI (Diffusion Tensor Imaging and T2-mapping) was performed on P14 and P28 and retinal and brain tissue were examined for histopathological changes. Long-term neurodevelopment was assessed on P20 and P27. RESULTS Mean, radial and axial diffusivity were higher in white matter of IHH versus controls at P14 (p < 0.04), while fractional anisotropy (FA) was lower in the hippocampal fimbria and tended to be lower in corpus callosum (p = 0.08) and external capsule (p = 0.05). White matter diffusivity in IHH was similar to controls at P28. Higher cortical vessel density (p = 0.005) was observed at P14. Cortical and thalamic T2-relaxation time and mean diffusivity were higher in the IHH group at P14 (p ≤ 0.03), and albumin leakage was present at P28. Rats in the IHH group ran for a longer time on a Rotarod than the control group (p ≤ 0.005). Pups with lower bodyweight had more severe MRI alterations and albumin leakage. CONCLUSION IHH led to subtle reversible changes in brain white matter diffusivity, grey matter water content and vascular density. However, alterations in blood-brain barrier permeability may point to long-term effects. The changes seen after IHH exposure were more severe in animals with lower bodyweight and future studies should aim at exploring possible interactions between IHH and growth restriction.
Collapse
Affiliation(s)
- Tora Sund Morken
- Department of Laboratory Medicine, Children’s and Women’s Health, Norwegian University of Science and Technology (NTNU), Trondheim, Norway
| | - Axel Karl Gottfrid Nyman
- Department of Circulation and Medical Imaging, Norwegian University of Science and Technology, Trondheim, Norway
| | - Ioanna Sandvig
- Department of Circulation and Medical Imaging, Norwegian University of Science and Technology, Trondheim, Norway
| | - Sverre Helge Torp
- Department of Laboratory Medicine, Children’s and Women’s Health, Norwegian University of Science and Technology (NTNU), Trondheim, Norway
| | - Jon Skranes
- Department of Laboratory Medicine, Children’s and Women’s Health, Norwegian University of Science and Technology (NTNU), Trondheim, Norway
- Department of Pediatrics, St. Olav University Hospital, Central Norway Regional Health Authority, Trondheim, Norway
| | - Pål Erik Goa
- Department of Radiology, St. Olav University Hospital, Central Norway Regional Health Authority, Trondheim, Norway
| | - Ann-Mari Brubakk
- Department of Laboratory Medicine, Children’s and Women’s Health, Norwegian University of Science and Technology (NTNU), Trondheim, Norway
- Department of Pediatrics, St. Olav University Hospital, Central Norway Regional Health Authority, Trondheim, Norway
| | - Marius Widerøe
- Department of Circulation and Medical Imaging, Norwegian University of Science and Technology, Trondheim, Norway
| |
Collapse
|
25
|
Hamel D, Sanchez M, Duhamel F, Roy O, Honoré JC, Noueihed B, Zhou T, Nadeau-Vallée M, Hou X, Lavoie JC, Mitchell G, Mamer OA, Chemtob S. G-protein-coupled receptor 91 and succinate are key contributors in neonatal postcerebral hypoxia-ischemia recovery. Arterioscler Thromb Vasc Biol 2013; 34:285-93. [PMID: 24285580 DOI: 10.1161/atvbaha.113.302131] [Citation(s) in RCA: 55] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
OBJECTIVE Prompt post-hypoxia-ischemia (HI) revascularization has been suggested to improve outcome in adults and newborn subjects. Other than hypoxia-inducible factor, sensors of metabolic demand remain largely unknown. During HI, anaerobic respiration is arrested resulting in accumulation of carbohydrate metabolic intermediates. As such succinate readily increases, exerting its biological effects via a specific receptor, G-protein-coupled receptor (GPR) 91. We postulate that succinate/GPR91 enhances post-HI vascularization and reduces infarct size in a model of newborn HI brain injury. APPROACH AND RESULTS The Rice-Vannucci model of neonatal HI was used. Succinate was measured by mass spectrometry, and microvascular density was evaluated by quantification of lectin-stained cryosection. Gene expression was evaluated by real-time polymerase chain reaction. Succinate levels rapidly increased in the penumbral region of brain infarcts. GPR91 was foremost localized not only in neurons but also in astrocytes. Microvascular density increased at 96 hours after injury in wild-type animals; it was diminished in GPR91-null mice leading to an increased infarct size. Stimulation with succinate led to an increase in growth factors implicated in angiogenesis only in wild-type mice. To explain the mode of action of succinate/GPR91, we investigated the role of prostaglandin E2-prostaglandin E receptor 4, previously proposed in neural angiogenesis. Succinate-induced vascular endothelial growth factor expression was abrogated by a cyclooxygenase inhibitor and a selective prostaglandin E receptor 4 antagonist. This antagonist also abolished succinate-induced neovascularization. CONCLUSIONS We uncover a dominant metabolic sensor responsible for post-HI neurovascular adaptation, notably succinate/GPR91, acting via prostaglandin E2-prostaglandin E receptor 4 to govern expression of major angiogenic factors. We propose that pharmacological intervention targeting GPR91 could improve post-HI brain recovery.
Collapse
Affiliation(s)
- David Hamel
- From the Department of Pediatrics, Research Center-CHU Ste-Justine, Montréal, Quebec, Canada (D.H., O.R., J.C.H., T.Z., X.H., J.-C.L., G.A.M., S.C.); Departments of Pharmacology (D.H., F.D., S.C.) and Biomedical Sciences (O.R., M.N.-V.), Université de Montréal, Montréal, Quebec, Canada; and Department of Pharmacology and Therapeutics (M.S., B.N., S.C.), Goodman Cancer Research and Metabolomics Core Facility (O.A.M.), McGill University, Montréal, Quebec, Canada
| | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
26
|
Prager S, Singer BB, Bendix I, Schlager GW, Bertling F, Ceylan B, Keller M, Felderhoff-Mueser U, Ergün S. CEACAM1 expression in oligodendrocytes of the developing rat brain shows a spatiotemporal relation to myelination and is altered in a model of encephalopathy of prematurity. Dev Neurosci 2013; 35:226-40. [PMID: 23651919 DOI: 10.1159/000348436] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2012] [Accepted: 01/28/2013] [Indexed: 11/19/2022] Open
Abstract
CEACAM1 is the founder molecule of the family of 'carcinoembryonic antigen-related cell adhesion molecules' and part of the immunoglobulin superfamily. Due to its role as a coreceptor to many other receptors (e.g. Toll-like receptor 2, Toll-like receptor 4, T-cell receptor, B-cell receptor, epidermal growth factor receptor and vascular endothelial growth factor receptor) and its different isoforms, CEACAM1 is a multifunctional protein with an impact on proliferation and differentiation of multiple cell types. Although different modes of action in other tissues are described, the role of CEACAM1 in the developing brain remains elusive. Here we report for the first time that CEACAM1 is expressed ontogenetically in oligodendrocytes of the developing rat brain, and that CEACAM1 expression has a spatiotemporal relation to myelination. In addition, CEACAM1 expression is altered in a model of hyperoxia- and inflammation-induced encephalopathy of prematurity, a myelination disorder of children born preterm. Furthermore, primary oligodendrocytes stimulated with CEACAM1 show increased myelination. Therefore, we postulate that CEACAM1 is, at least in part, involved in hyperoxia- and inflammation-induced disruption of myelination, but may also play a role in intact myelination as it is ontogenetically expressed in myelinating oligodendrocytes.
Collapse
Affiliation(s)
- Sebastian Prager
- Department of Pediatrics 1, Neonatology, University Hospital Essen, Essen, Germany.
| | | | | | | | | | | | | | | | | |
Collapse
|
27
|
Honoré JC, Kooli A, Hamel D, Alquier T, Rivera JC, Quiniou C, Hou X, Kermorvant-Duchemin E, Hardy P, Poitout V, Chemtob S. Fatty acid receptor Gpr40 mediates neuromicrovascular degeneration induced by transarachidonic acids in rodents. Arterioscler Thromb Vasc Biol 2013; 33:954-61. [PMID: 23520164 DOI: 10.1161/atvbaha.112.300943] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
OBJECTIVE Nitro-oxidative stress exerts a significant role in the genesis of hypoxic-ischemic (HI) brain injury. We previously reported that the ω-6 long chain fatty acids, transarachidonic acids (TAAs), which are nitrative stress-induced nonenzymatically generated arachidonic acid derivatives, trigger selective microvascular endothelial cell death in neonatal neural tissue. The primary molecular target of TAAs remains unidentified. GPR40 is a G protein-coupled receptor activated by long chain fatty acids, including ω-6; it is highly expressed in brain, but its functions in this tissue are largely unknown. We hypothesized that TAAs play a significant role in neonatal HI-induced cerebral microvascular degeneration through GPR40 activation. APPROACH AND RESULTS Within 24 hours of a HI insult to postnatal day 7 rat pups, a cerebral infarct and a 40% decrease in cerebrovascular density was observed. These effects were associated with an increase in nitrative stress markers (3-nitrotyrosine immunoreactivity and TAA levels) and were reduced by treatment with nitric oxide synthase inhibitor. GPR40 was expressed in rat pup brain microvasculature. In vitro, in GPR40-expressing human embryonic kidney (HEK)-293 cells, [(14)C]-14E-AA (radiolabeled TAA) bound specifically, and TAA induced calcium transients, extracellular signal-regulated kinase 1/2 phosphorylation, and proapoptotic thrombospondin-1 expression. In vivo, intracerebroventricular injection of TAAs triggered thrombospondin-1 expression and cerebral microvascular degeneration in wild-type mice, but not in GPR40-null congeners. Additionally, HI-induced neurovascular degeneration and cerebral infarct were decreased in GPR40-null mice. CONCLUSIONS GPR40 emerges as the first identified G protein-coupled receptor conveying actions of nonenzymatically generated nitro-oxidative products, specifically TAAs, and is involved in (neonatal) HI encephalopathy.
Collapse
Affiliation(s)
- Jean-Claude Honoré
- Department of Pediatrics, Research Center-CHU Ste-Justine, Montréal, Quebec, Canada
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
28
|
Mayo JN, Beard RS, Price TO, Chen CH, Erickson MA, Ercal N, Banks WA, Bearden SE. Nitrative stress in cerebral endothelium is mediated by mGluR5 in hyperhomocysteinemia. J Cereb Blood Flow Metab 2012; 32:825-34. [PMID: 22186670 PMCID: PMC3345916 DOI: 10.1038/jcbfm.2011.185] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Hyperhomocysteinemia (HHcy) disrupts nitric oxide (NO) signaling and increases nitrative stress in cerebral microvascular endothelial cells (CMVECs). This is mediated, in part, by protein nitrotyrosinylation (3-nitrotyrosine; 3-NT) though the mechanisms by which extracellular homocysteine (Hcy) generates intracellular 3-NT are unknown. Using a murine model of mild HHcy (cbs(+/-) mouse), we show that 3-NT is significantly elevated in cerebral microvessels with concomitant reductions in serum NO bioavailability as compared with wild-type littermate controls (cbs(+/+)). Directed pharmacology identified a receptor-dependent mechanism for 3-NT formation in CMVECs. Homocysteine increased expression of inducible NO synthase (iNOS) and formation of 3-NT, both of which were blocked by inhibition of metabotropic glutamate receptor-5 (mGluR5) with the specific antagonist 2-methyl-6-(phenylethynyl) pyridine hydrochloride. Activation of mGluR5 is both sufficient and necessary to drive the nitrative stress because direct activation using the mGluR5-specific agonist (RS)-2-chloro-5-hydroxyphenylglycine also increased iNOS expression and 3-NT formation while knockdown of mGluR5 receptor expression by short hairpin RNA (shRNA) blocked their increase in response to Hcy. Nitric oxide derived from iNOS was required for Hcy-mediated formation of 3-NT because the effect was blocked by 1400W. These results provide the first evidence for a receptor-dependent process that explains how plasma Hcy levels control intracellular nitrative stress in cerebral microvascular endothelium.
Collapse
Affiliation(s)
- Jamie N Mayo
- Department of Biological Sciences, Idaho State University, Pocatello, ID 83209, USA
| | | | | | | | | | | | | | | |
Collapse
|
29
|
Zaghloul N, Nasim M, Patel H, Codipilly C, Marambaud P, Dewey S, Schiffer WK, Ahmed M. Overexpression of extracellular superoxide dismutase has a protective role against hyperoxia-induced brain injury in neonatal mice. FEBS J 2012; 279:871-81. [PMID: 22240000 DOI: 10.1111/j.1742-4658.2012.08478.x] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
There is increasing evidence that hyperoxia, particularly at the time of birth, may result in neurological injury, in particular to the susceptible vasculature of these tissues. This study was aimed at determining whether overexpression of extracellular superoxide dismutase (EC-SOD) is protective against brain injury induced by hyperoxia. Transgenic (TG) mice (with an extra copy of the human extracellular superoxide dismutase gene) and wild-type (WT) neonate mice were exposed to hyperoxia (95% of F(i) o(2) ) for 7 days after birth versus the control group in room air. Brain positron emission tomography (PET) scanning with fludeoxyglucose (FDG) isotope uptake was performed after exposure. To assess apoptosis induced by hyperoxia exposure, caspase 3 ELISA and terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) staining were performed. Quantitative western blot for the following inflammatory markers was performed: glial fibrillary acidic protein, ionized calcium-binding adaptor molecule 1, macrophage-inhibiting factor, and phospho-AMP-activated protein kinase. PET scanning with FDG isotope uptake showed significantly higher uptake in the WT hyperoxia neonate brain group (0.14 ± 0.03) than in both the TG group (0.09 ± 0.01) and the control group (0.08 ± 0.02) (P< 0.05). Histopathological investigation showed more apoptosis and dead neurons in hippocampus and cerebellum brain sections of WT neonate mice after exposure to hyperoxia than in TG mice; this finding was also confirmed by TUNEL staining. The caspase 3 assay confirmed the finding of more apoptosis in WT hyperoxia neonates (0.814 ± 0.112) than in the TG hyperoxic group (0.579 ± 0.144) (P < 0.05); this finding was also confirmed by TUNEL staining. Quantitative western blotting for the inflammatory and metabolic markers showed significantly higher expression in the WT group than in the TG and control groups. Thus, overexpression of EC-SOD in the neonate brain offers significant protection against hyperoxia-induced brain damage.
Collapse
Affiliation(s)
- Nahla Zaghloul
- Department of Pediatrics, Cohen Children's Medical Center, NS-LIJ, Manhasset, NY 11030, USA
| | | | | | | | | | | | | | | |
Collapse
|
30
|
Li J, Yu S, Lu Z, Mohamad O, Wei L. N-methyl-D-aspartate receptor subtype 3A promotes apoptosis in developing mouse brain exposed to hyperoxia. Neural Regen Res 2012; 7:273-7. [PMID: 25806068 PMCID: PMC4353099 DOI: 10.3969/j.issn.1673-5374.2012.04.006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2011] [Accepted: 12/22/2011] [Indexed: 11/18/2022] Open
Abstract
In the present study, 7 day postnatal C57/BL6 wild-type mice (hyperoxia group) and 7 day postnatal N-methyl-D-aspartate receptor subtype 3A knockout mice (NR3A KO group) were exposed to 75% oxygen and 15% nitrogen in a closed container for 5 days. Wild-type mice raised in normoxia served as controls. TdT-mediated dUTP nick end labeling (TUNEL)/neuron-specific nuclear protein (NeuN) and 5-bromo-2'-deoxyuridine (BrdU)/NeuN immunofluorescence staining showed that the number of apoptotic cells and the number of proliferative cells in the dentate subgranular zone significantly increased in the hyperoxia group compared with the control group. However, in the same hyperoxia environment, the number of apoptotic cells and the number of proliferative cells significantly decreased in the NR3A KO group compared with hyperoxia group. TUNEL(+)/NeuN(+) and BrdU(+)/NeuN(+) cells were observed in the NR3A KO and the hyperoxia groups. These results demonstrated that the NR3A gene can promote cell apoptosis and mediate the potential damage in the developing brain induced by exposure to non-physiologically high concentrations of oxygen.
Collapse
Affiliation(s)
- Jimei Li
- Department of Neurology, Beijing Friendship Hospital, Capital Medical University, Beijing 100050, China ; Departments of Pathology and Laboratory Medicine, Medical University of South Carolina, SC 29425, USA
| | - Shanping Yu
- Department of Anesthesiology, Emory University School of Medicine, Atlanta, GA 30322, USA
| | - Zhongyang Lu
- Departments of Pathology and Laboratory Medicine, Medical University of South Carolina, SC 29425, USA
| | - Osama Mohamad
- Department of Anesthesiology, Emory University School of Medicine, Atlanta, GA 30322, USA
| | - Ling Wei
- Departments of Pathology and Laboratory Medicine, Medical University of South Carolina, SC 29425, USA ; Department of Anesthesiology, Emory University School of Medicine, Atlanta, GA 30322, USA
| |
Collapse
|
31
|
Wayenberg JL, Cavedon C, Ghaddhab C, Lefèvre N, Bottari SP. Early transient hypoglycemia is associated with increased albumin nitration in the preterm infant. Neonatology 2011; 100:387-97. [PMID: 21791930 DOI: 10.1159/000326936] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/05/2010] [Accepted: 03/03/2011] [Indexed: 01/08/2023]
Abstract
BACKGROUND The clinical significance of early transient hypoglycemia (ETH), a frequent event in preterm newborns, is a highly controversial issue. In experimental models, hypoglycemia has been reported to cause oxidative stress. Among the reactive species, early generated peroxynitrite is responsible for protein nitration and lipid peroxidation, a process referred to as nitrative stress. OBJECTIVES The aim of the present study is to investigate whether ETH is associated with protein nitration in the preterm newborn. METHODS Using a novel highly sensitive ELISA, we quantified plasma nitroalbumin (PNA) as a marker of peroxynitrite generation in 72 preterm newborns (28-36 weeks), among which 25 had a glycemia level of <2.5 mmol/l during the first hour of life (H1). RESULTS PNA was significantly higher in ETH than in normoglycemic infants at H1 [median = 6.3 (3.8-8.8) vs. 3.4 ng/ml (2.1-5.1), p = 0.027] and at day 1 [median = 6.6 (5.6-15.3) vs. 3.9 ng/ml (2.3-4.6), p = 0.014]. PNA was inversely correlated with glycemia at H1 (r = -0.30, p = 0.01) and at day 1 (r = -0.63, p = 0.001). In ETH infants, lactatemia was inversely correlated with PNA. At day 1, PNA was higher in ETH infants treated by gavage than in those treated with intravenous dextrose [median = 8.9 ng/ml (7.1-10.4) vs. 4.4 ng/ml (2.6-5.7), p = 0.008]. CONCLUSIONS These results indicate that ETH is associated with increased peroxynitrite generation resulting in systemic protein nitration in premature newborns. Treatment of ETH with intravenous dextrose is associated with lower PNA levels than gavage.
Collapse
Affiliation(s)
- Jean-Louis Wayenberg
- Department of Pediatrics, Hôpital Universitaire des Enfants Reine Fabiola, Université Libre de Bruxelles, Brussels, Belgium
| | | | | | | | | |
Collapse
|
32
|
Honoré JC, Kooli A, Hou X, Hamel D, Rivera JC, Picard É, Hardy P, Tremblay S, Varma DR, Jankov RP, Mancini JA, Balazy M, Chemtob S. Sustained hypercapnia induces cerebral microvascular degeneration in the immature brain through induction of nitrative stress. Am J Physiol Regul Integr Comp Physiol 2010; 298:R1522-30. [DOI: 10.1152/ajpregu.00807.2009] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
Hypercapnia is regularly observed in chronic lung disease, such as bronchopulmonary dysplasia in preterm infants. Hypercapnia results in increased nitric oxide synthase activity and in vitro formation of nitrates. Neural vasculature of the immature subject is particularly sensitive to nitrative stress. We investigated whether exposure to clinically relevant sustained high CO2 causes microvascular degeneration in the newborn brain by inducing nitrative stress, and whether this microvascular degeneration has an impact on brain growth. Newborn rat pups were exposed to 10% CO2 as inspired gas (PaCO2 = 60–70 mmHg) starting within 24 h of birth until postnatal day 7 (P7). Brains were notably collected at different time points to measure vascular density, determine brain cortical nitrite/nitrate, and trans-arachidonic acids (TAAs; products of nitration) levels as effectors of vessel damage. Chronic exposure of rat pups to high CO2 (PaCO2 ≈ 65 mmHg) induced a 20% loss in cerebrovascular density at P3 and a 15% decrease in brain mass at P7; at P30, brain mass remained lower in CO2-exposed animals. Within 24 h of exposure to CO2, brain eNOS expression and production of nitrite/nitrate doubled, lipid nitration products (TAAs) increased, and protein nitration (3-nitrotyrosine immunoreactivity) was also coincidently augmented on brain microvessels (lectin positive). Intracerebroventricular injection of TAAs (10 μM) replicated cerebrovascular degeneration. Treatment of rat pups with NOS inhibitor (l-Nω-nitroarginine methyl ester) or a peroxynitrite decomposition catalyst (FeTPPS) prevented hypercapnia-induced microvascular degeneration and preserved brain mass. Cytotoxic effects of high CO2 were reproduced in vitro /ex vivo on cultured endothelial cells and sprouting microvessels. In summary, hypercapnia at values frequently observed in preterm infants with chronic lung disease results in increased nitrative stress, which leads to cerebral cortical microvascular degeneration and curtails brain growth.
Collapse
Affiliation(s)
- Jean-Claude Honoré
- Department of Pediatrics, Research Center-Centre Hospitalier Universitaire Ste-Justine, Montréal, Quebec, Canada
- Department of Pharmacology, Université de Montréal, Quebec, Canada
| | - Amna Kooli
- Department of Pediatrics, Research Center-Centre Hospitalier Universitaire Ste-Justine, Montréal, Quebec, Canada
- Department of Pharmacology and Therapeutics, McGill University, Montréal, Quebec, Canada
| | - Xin Hou
- Department of Pediatrics, Research Center-Centre Hospitalier Universitaire Ste-Justine, Montréal, Quebec, Canada
| | - David Hamel
- Department of Pediatrics, Research Center-Centre Hospitalier Universitaire Ste-Justine, Montréal, Quebec, Canada
- Department of Pharmacology, Université de Montréal, Quebec, Canada
| | - José Carlos Rivera
- Department of Pediatrics, Research Center-Centre Hospitalier Universitaire Ste-Justine, Montréal, Quebec, Canada
- Department of Pharmacology, Université de Montréal, Quebec, Canada
| | - Émilie Picard
- Department of Pediatrics, Research Center-Centre Hospitalier Universitaire Ste-Justine, Montréal, Quebec, Canada
- Department of Pharmacology, Université de Montréal, Quebec, Canada
| | - Pierre Hardy
- Department of Pediatrics, Research Center-Centre Hospitalier Universitaire Ste-Justine, Montréal, Quebec, Canada
- Department of Pharmacology, Université de Montréal, Quebec, Canada
| | - Sophie Tremblay
- Department of Pediatrics, Research Center-Centre Hospitalier Universitaire Ste-Justine, Montréal, Quebec, Canada
| | - Daya R. Varma
- Department of Pharmacology and Therapeutics, McGill University, Montréal, Quebec, Canada
| | - Robert P. Jankov
- Department of Pediatrics, University of Toronto, Toronto, Ontario, Canada; and
| | - Joseph A. Mancini
- Department of Pediatrics, Research Center-Centre Hospitalier Universitaire Ste-Justine, Montréal, Quebec, Canada
| | - Michael Balazy
- Department of Pathology, New York Medical College, New York, New York
| | - Sylvain Chemtob
- Department of Pediatrics, Research Center-Centre Hospitalier Universitaire Ste-Justine, Montréal, Quebec, Canada
- Department of Pharmacology, Université de Montréal, Quebec, Canada
- Department of Pharmacology and Therapeutics, McGill University, Montréal, Quebec, Canada
| |
Collapse
|
33
|
Inhaled nitric oxide prevents 3-nitrotyrosine formation in the lungs of neonatal mice exposed to >95% oxygen. Lung 2010; 188:217-27. [PMID: 20237791 DOI: 10.1007/s00408-010-9235-6] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2009] [Accepted: 03/02/2010] [Indexed: 10/19/2022]
Abstract
Inhaled nitric oxide is being evaluated as a preventative therapy for patients at risk for bronchopulmonary dysplasia (BPD). Nitric oxide (NO), in the presence of superoxide, forms peroxynitrite, which reacts with tyrosine residues on proteins to form 3-nitrotyrosine (3-NT). However, NO can also act as an antioxidant and was recently found to improve the oxidative balance in preterm infants. Thus, we tested the hypothesis that the addition of a therapeutically relevant concentration (10 ppm) of NO to a hyperoxic exposure would lead to decreased 3-NT formation in the lung. FVB mouse pups were exposed to either room air (21% O(2)) or >95% O(2) with or without 10 ppm NO within 24 h of birth. In the first set of studies, body weights and survival were monitored for 7 days, and exposure to >95% O(2) resulted in impaired weight gain and near 100% mortality by 7 days. However, the mortality occurred earlier in pups exposed to >95% O(2) + NO than in pups exposed to >95% O(2) alone. In a second set of studies, lungs were harvested at 72 h. Immunohistochemistry of the lungs at 72 h revealed that the addition of NO decreased alveolar, bronchial, and vascular 3-NT staining in pups exposed to both room air and hyperoxia. The lung nitrite levels were higher in animals exposed to >95% oxygen + NO than in animals exposed to >95% oxygen alone. The protein levels of myeloperoxidase, monocyte chemotactic protein-1, and intracellular adhesion molecule-1 were assessed after 72 h of exposure and found to be greatest in the lungs of pups exposed to >95% O(2). This hyperoxia-induced protein expression was significantly attenuated by the addition of 10 ppm NO. We propose that in the presence of >95% O(2), peroxynitrite formation results in protein nitration; however, adding excess NO to the >95% O(2) exposure prevents 3-NT formation by NO reacting with peroxynitrite to produce nitrite and NO(2). We speculate that the decreased protein nitration observed with the addition of NO may be a potential mechanism limiting hyperoxic lung injury.
Collapse
|
34
|
Kunert MP, Friesma J, Falck JR, Lombard JH. CYP450 4A inhibition attenuates O2 induced arteriolar constriction in chronic but not acute Goldblatt hypertension. Microvasc Res 2009; 78:442-6. [PMID: 19761780 DOI: 10.1016/j.mvr.2009.09.002] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2009] [Revised: 08/13/2009] [Accepted: 09/08/2009] [Indexed: 10/20/2022]
Abstract
We explored the role of 20-hydroxy-5Z, 8Z, 11Z, 14Z-eicosatetraenoic acid (20-HETE) in oxygen-induced vasoconstriction in a normal renin form of hypertension [the 1 kidney-1 clip Goldblatt hypertensive rat (1K1C)] and a high renin form of hypertension [the 2 kidney-1 clip Goldblatt hypertensive rat (2K1C)]. A silver clip was placed around the left renal artery of adult Sprague-Dawley males. The right kidney was removed in the 1K1C group and left intact in the 2K1C group. Arteriolar responses to elevation of O(2) concentration in the superfusion solution from 0% O(2) to 21% O(2) were determined in the in situ cremaster muscle before and after inhibition of cytochrome P450 4A omega-hydroxylase (CYP450 4A) with N-methyl-sulfonyl-12, 12-dibromododec-11-enamide (DDMS). Arteriolar constriction to elevated PO(2) was enhanced in the chronic 1K1C but not the acute 1K1C or 2K1C. DDMS eliminated O(2)-induced arteriolar constriction in the 9-week 1K1C, but had no effect in the 2-week 1K1C, and only partially inhibited O(2)-induced constriction of arterioles in the 4-week 2K1C rat. These findings indicate that although the CYP4A/20-HETE system contributes to arteriolar constriction in response to elevated PO(2) in the established stage of 1K1C renovascular hypertension, physiological alterations in other mechanisms are the primary determinants of O(2)-induced constriction of arterioles in the early and developing stages of 1K1C and 2K1C hypertension.
Collapse
|
35
|
Effect of hyperoxia on serine phosphorylation of apoptotic proteins in mitochondrial membranes of the cerebral cortex of newborn piglets. Neurochem Res 2009; 34:1219-25. [PMID: 19169818 DOI: 10.1007/s11064-008-9898-z] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/17/2008] [Indexed: 10/21/2022]
Abstract
Previous studies have shown that hyperoxia results in cerebral cortical neuronal apoptosis. Studies have also shown that phosphorylation of anti-apoptotic proteins Bcl-2 and Bcl-xl results in loss of their anti-apoptotic potential leading to alteration in mitochondrial membrane permeability and the release of apoptogenic proteins in the neuronal cell of the newborn piglets. The present study tests the hypothesis that cerebral hyperoxia will result in increased serine phosphorylation of apoptotic proteins Bcl-2, Bcl-xl, Bax, and Bad in the mitochondrial membranes of the cerebral cortex of newborn piglets. Twelve newborn piglets were divided into normoxic (Nx, n = 6) exposed to an FiO(2) of 0.21 for 1 h and hyperoxic (Hyx, n = 6) exposed to FiO(2) of 1.0 for 1 h. In the Hyx group, PaO(2) was maintained above 400 mmHg while the Nx group was kept at 80-100 mmHg. Cerebral cortical tissue was harvested and mitochondrial fractions were isolated. Mitochondrial membrane proteins were separated using 12% SDS-PAGE, and probed with anti-serine phosphorylated Bcl-2, Bcl-xl, Bax, and Bad antibodies. Protein bands were detected, analyzed by imaging densitometry and density expressed as absorbance (OD x mm(2)). Phosphorylated Bcl-2 (p-Bcl-2) protein density (OD x mm(2)) was 81.81 +/- 9.24 in Nx and 158.34 +/- 10.66 in Hyx (P < 0.05). Phosphorylated Bcl-xl (p-Bcl-xl) protein density was 52.98 +/- 3.59 in Nx and 99.62 +/- 18.22 in Hyx (P < 0.05). Phosphorylated Bax (p-Bax) protein was 161.13 +/- 6.27 in Nx and 174.21 +/- 15.95 in Hyx (P = NS). Phosphorylated Bad (p-Bad) protein was 166.24 +/- 9.47 in Nx 155.38 +/- 12.32 in Hyx (P = NS). The data show that there is a significant increase in serine phosphorylation of Bcl-2 and Bcl-xl proteins while phosphorylation of Bad and Bax proteins were not altered during hyperoxia in the mitochondrial fraction of the cerebral cortex of newborn piglets. We conclude that hyperoxia results in differential post-translational modification of anti-apoptotic proteins Bcl-2 and Bcl-xl as compared to pro-apoptotic proteins Bax and Bad in mitochondria. We speculate that phosphorylation of Bcl-2 and Bcl-xl will result in loss of their anti-apoptotic potential by preventing their dimerization with Bax leading to activation of the caspase cascade of neuronal death.
Collapse
|
36
|
Dzietko M, Boos V, Sifringer M, Polley O, Gerstner B, Genz K, Endesfelder S, Börner C, Jacotot E, Chauvier D, Obladen M, Bührer C, Felderhoff-Mueser U. A critical role for Fas/CD-95 dependent signaling pathways in the pathogenesis of hyperoxia-induced brain injury. Ann Neurol 2009; 64:664-73. [PMID: 19107989 DOI: 10.1002/ana.21516] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
OBJECTIVE Prematurely born infants are at risk for development of neurocognitive impairment in later life. Oxygen treatment has been recently identified as a trigger of neuronal and oligodendrocyte apoptosis in the developing rodent brain. We investigated the role of the Fas death receptor pathway in oxygen-triggered developmental brain injury. METHODS Six-day-old Wistar rats were exposed to 80% oxygen for various periods (2, 6, 12, 24, 48, and 72 hours), and mice deficient in either Fas (B6.MRL-Tnfrsf6(lpr)) or Fas ligand (B6Smn.C3-Fasl(gld)) and control mice (C57BL/6J) were exposed to 80% oxygen for 24 hours. Polymerase chain reaction, Western blotting, and caspase activity assays of thalamus and cortex tissue were performed. RESULTS Fas and Fas ligand messenger RNA and protein were upregulated. Furthermore, hyperoxia resulted in induction of downstream signaling events of Fas, such as Fas-associated death domain (FADD), the long and short form of FADD-like interleukin-1beta-converting enzyme (FLICE) inhibitory protein (FLIP-L, FLIP-S), and cleavage of caspase-8 and caspase-3. Injection of a selective caspase-8 inhibitor (TRP801, 1mg/kg) at the beginning of hyperoxia blocked subsequent caspase-3 cleavage in this model. B6.MRL-Tnfrsf6(lpr) mice were protected against oxygen-mediated injury, confirming Fas involvement in hyperoxia-induced cell death. Mice deficient in Fas ligand did not differ from control animals in the amount of cell death. INTERPRETATION We conclude that neonatal hyperoxia triggers Fas receptor and its downstream signaling events in a Fas ligand-independent fashion. Lack of functional Fas receptors and selective pharmacological inhibition of caspase-8 prevents activation of caspase-3 and provides significant neuroprotection.
Collapse
Affiliation(s)
- Mark Dzietko
- Department of Neonatology, Charité, Universitätsmedizin-Berlin, Campus Virchow Klinikum, Berlin, Germany.
| | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
37
|
Stark S, Schuller A, Sifringer M, Gerstner B, Brehmer F, Weber S, Altmann R, Obladen M, Buhrer C, Felderhoff-Mueser U. Suramin induces and enhances apoptosis in a model of hyperoxia-induced oligodendrocyte injury. Neurotox Res 2008; 13:197-207. [PMID: 18522899 DOI: 10.1007/bf03033503] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
Recent evidence suggests oxygen as a powerful trigger for cell death in the immature white matter, leading to periventricular leukomalacia (PVL) as a cause of adverse neurological outcome in survivors of preterm birth. This oligodendrocyte (OL) death is associated with oxidative stress, upregulation of apoptotic signaling factors (i.e., Fas, caspase-3) and decreased amounts of neurotrophins. In search of neuroprotective strategies we investigated whether the polysulfonated urea derivative suramin, recently identified as a potent inhibitor of Fas signaling, affords neuroprotection in an in vitro model of hyperoxia-induced injury to immature oligodendrocytes. Immature OLs (OLN-93) were subjected to 80% hyperoxia (48 h) in the presence or absence of suramin (0, 30, 60, 120 microM). Cell death was assessed by flow cytometry (Annexin V, caspase-3 activity assay) and immunohistochemistry for activated caspase-3. Immunoblotting for the death receptor Fas, cleaved caspase-8 and the phosphorylated isoform of the serine-threonin kinase Akt (pAkt) was performed. Suramin lead to OL apoptosis and potentiated hyperoxia-induced injury in a dose-dependent manner. Immunoblotting revealed increased Fas and caspase-8 expression by suramin treatment. This effect was significantly enhanced when suramin was combined with hyperoxia. Furthermore, pAkt levels decreased following suramin exposure, indicating interference with neurotrophin-dependent growth factor signaling. These data indicate that suramin causes apoptotic cell death and aggravates hyperoxia-induced cell death in immature OLs. Its mechanism of action includes an increase of previously described hyperoxia-induced expression of pro-apoptotic factors and deprivation of growth factor dependent signaling components.
Collapse
Affiliation(s)
- Simone Stark
- Department of Neonatology, Campus Virchow-Klinikum, Charité, Universitätsmedizin Berlin, D-13353 Berlin, Germany
| | | | | | | | | | | | | | | | | | | |
Collapse
|
38
|
Yiş U, Kurul SH, Kumral A, Tuğyan K, Cilaker S, Yilmaz O, Genç S, Genç K. Effect of erythropoietin on oxygen-induced brain injury in the newborn rat. Neurosci Lett 2008; 448:245-9. [PMID: 18973793 DOI: 10.1016/j.neulet.2008.10.060] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2008] [Revised: 10/12/2008] [Accepted: 10/14/2008] [Indexed: 11/17/2022]
Abstract
The developing nervous system is sensitive to supraphysiological oxygen concentrations. Recent studies showed that exposure to hyperoxia in infant rats leads to extensive apoptotic degeneration in the cortex and white matter of the developing brain. A wide variety of experimental studies have shown that erythropoietin exerts a remarkable neuroprotection in both cell cultures and in animal models of nervous system disorders. In the present study, we investigated the effect of erythropoietin against hyperoxia-induced neurodegeneration in the developing brain. Eighteen Wistar rat pups were divided into three groups: control group, hyperoxia+saline-treated group and hyperoxia+erythropoietin-treated group. Hyperoxia groups were exposed to 80% oxygen (n=12) in a plexiglas chamber in which the oxygen concentration was monitored twice daily from birth until postnatal day 5. Hyperoxia exposure was 24h/day for 5 days. The hyperoxia+erythropoietin group received an intraperitoneal injection of recombinant human erythropoietin at a dose of 1000U/(kgday). At postnatal day 5, all animals were sacrificed. Neuronal cell death and apoptosis were evaluated. Histopathological examination showed that erythropoietin significantly diminished apoptosis in the CA1 region and dentate gyrus of hippocampus and parietal cortex in hyperoxia+erythropoietin-treated group. Regarding the safety profile of erythropoietin in premature and mature infants, this agent may be potentially beneficial in preventing hyperoxic brain injury.
Collapse
Affiliation(s)
- Uluç Yiş
- Department of Pediatric Neurology, School of Medicine, Dokuz Eylül University, Inciralti, 35340 Izmir, Turkey.
| | | | | | | | | | | | | | | |
Collapse
|
39
|
Quiniou C, Kooli E, Joyal JS, Sapieha P, Sennlaub F, Lahaie I, Shao Z, Hou X, Hardy P, Lubell W, Chemtob S. Interleukin-1 and ischemic brain injury in the newborn: development of a small molecule inhibitor of IL-1 receptor. Semin Perinatol 2008; 32:325-33. [PMID: 18929155 DOI: 10.1053/j.semperi.2008.07.001] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Inflammation participates in the genesis and progression of hypoxic-ischemic brain injury. Interleukin (IL)-1 is a major pro-inflammatory cytokine, which plays a dominant role in hypoxic-ischemic (and postinfectious) brain damage. Abundant evidence reveals the principal involvement of IL-1 over other pro-inflammatory cytokines. IL-1 interacts with the IL-1 receptor I (IL-1RI). The natural IL-1 receptor antagonist (IL-1ra) is a large 17.5-kDa peptide that competes with IL-1 for its binding site on IL-1RI. Recombinant IL-1ra (Kineret) is effective in human inflammatory conditions. However, a number of drawbacks of IL-1ra limit its broader use; these include injection site reactions [70%], broad immunosuppression, and high costs. We hereby report the characterization of a small (peptide) IL-1RI antagonist we developed, namely rytvela (termed 101.10), and its efficacy in models of (gut) inflammation and of newborn hypoxic-ischemic brain injury. Experiments reveal that 101.10 is selective for the IL-1RI and inhibits to a variable extent different effects induced by IL-1. 101.10 is effective in vivo (on systemic as well as oral administration) in established models of inflammation involving IL-1, notably in inflammatory bowel disease, and is superior to dexamethasone. In a rat pup model of hypoxic-ischemic brain injury (Rice-Vannucci model), where IL-1 and IL-1R expression is increased, 101.10 preserved microvascular density, parenchymal integrity, and brain mass. In conclusion, we hereby describe for the first time the discovery of a stable, potent, and effective specific IL-1RI small (peptide) antagonist, namely 101.10 (rytvela), which exhibits allosteric modulatory properties, and is effective in vivo in models of inflammation (known to involve IL-1) and in particular in hypoxic-ischemic newborn brain injury. 101.10 (and small alike compounds) may be suitable alternatives to IL-1ra.
Collapse
Affiliation(s)
- Christiane Quiniou
- Department of Pediatrics and Pharmacology, Hôpital Ste Justine, Research Center, Montreal, Quebec, CA
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
40
|
Yiş U, Kurul SH, Kumral A, Cilaker S, Tuğyan K, Genç S, Yilmaz O. Hyperoxic exposure leads to cell death in the developing brain. Brain Dev 2008; 30:556-62. [PMID: 18329209 DOI: 10.1016/j.braindev.2008.01.010] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/27/2007] [Revised: 01/14/2008] [Accepted: 01/24/2008] [Indexed: 11/26/2022]
Abstract
Premature infants have high incidence of motor and cognitive impairment in later life. Supraphysiological oxygen concentrations are routinely used in neonatal intensive care units and elicit injury to premature lungs and retina. Since the effects of hyperoxia on the developing brain are scarce, we studied the effects of high oxygen on this tissue. Wistar rat pups were exposed from birth until day 5 to 21% or 80% oxygen. The neuronal density and apoptosis in CA1 and dentate gyrus of hippocampus, prefrontal cortex, parietal cortex, subiculum, and retrosplenial cortex were assessed by immunohistochemistry and ELISA cell death assay. Neuronal density of the investigated brain areas were significantly decreased in the hyperoxia group. Furthermore, using ELISA cell death and TUNEL assays, we observed increased cell death in the developing brain. Our results show that hyperoxia induces cell death in the developing rat brain. This may be one of the important mechanisms that cause motor and cognitive impairment in later life of premature infants.
Collapse
Affiliation(s)
- Uluç Yiş
- Department of Pediatric Neurology, School of Medicine, Dokuz Eylül University, Inciralti, 35340 Izmir, Turkey.
| | | | | | | | | | | | | |
Collapse
|
41
|
De Matteo R, Stacy V, Probyn ME, Brew N, Blasch N, Harding R. Does moderate preterm birth lead to altered arterial pressure? Studies in sheep. Clin Exp Pharmacol Physiol 2008; 35:1426-32. [PMID: 18671717 DOI: 10.1111/j.1440-1681.2008.05014.x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
1. Low birth weight (LBW) is associated with an increased risk of cardiovascular disease. Preterm birth is a major determinant of LBW and has been shown to result in elevated arterial pressure (AP) in humans, but few studies have investigated the effects of preterm birth in the absence of potentially confounding factors. Our aim was to determine whether moderately preterm birth per se alters the postnatal development of AP in lambs. 2. Preterm lambs were delivered approximately 14 days before term (i.e. approximately 133 days of gestation); controls were born at term (approximately 147 days). Mean arterial pressure (MAP), heart rate (HR), blood composition and indices of growth were measured at 4 and 8 weeks post term-equivalent age (PTEA). We also studied a separate cohort of preterm and term sheep as young adults (approximately 1.1 years). 3. Preterm lambs had significantly lower birth weights than term lambs, but bodyweights were not significantly different by Day 12 PTEA. In addition, MAP, HR and most blood variables did not differ between term and preterm lambs at 4 or 8 weeks PTEA. Preterm birth per se did not alter MAP or HR in young adult sheep. 4. Low birth weight due to preterm birth does not result in an altered AP during early postnatal life or at maturity. Moderate intrauterine growth restriction (IUGR) due to twinning, which further reduces birth weight, does not affect MAP in preterm lambs. Other factors, such as the degree of prematurity or IUGR, exposure to corticosteroids or postnatal nutrition, may be important in the later development of elevated AP.
Collapse
Affiliation(s)
- Robert De Matteo
- Department of Anatomy and Developmental Biology, Monash University, Clayton, Victoria, Australia.
| | | | | | | | | | | |
Collapse
|
42
|
Koch JD, Miles DK, Gilley JA, Yang CP, Kernie SG. Brief exposure to hyperoxia depletes the glial progenitor pool and impairs functional recovery after hypoxic-ischemic brain injury. J Cereb Blood Flow Metab 2008; 28:1294-306. [PMID: 18334993 PMCID: PMC2652354 DOI: 10.1038/jcbfm.2008.15] [Citation(s) in RCA: 64] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Patterns of hypoxic-ischemic brain injury in infants and children suggest vulnerability in regions of white matter development, and injured patients develop defects in myelination resulting in cerebral palsy and motor deficits. Reperfusion exacerbates the oxidative stress that occurs after such injuries and may impair recovery. Resuscitation after hypoxic-ischemic injury is routinely performed using 100% oxygen, and this practice may increase the oxidative stress that occurs during reperfusion and further damage an already compromised brain. We show that brief exposure (30 mins) to 100% oxygen during reperfusion worsens the histologic injury in young mice after unilateral brain hypoxia-ischemia, causes an accumulation of the oxidative metabolite nitrotyrosine, and depletes preoligodendrocyte glial progenitors present in the cortex. This damage can be reversed with administration of the antioxidant ebselen, a glutathione peroxidase mimetic. Moreover, mice recovered in 100% oxygen have a more disrupted pattern of myelination and develop a static motor deficit that mimics cerebral palsy and manifests itself by significantly worse performance on wire hang and rotorod motor testing. We conclude that exposure to 100% oxygen during reperfusion after hypoxic-ischemic brain injury increases secondary neural injury, depletes developing glial progenitors, interferes with myelination, and ultimately impairs functional recovery.
Collapse
Affiliation(s)
- Joshua D Koch
- Department of Pediatrics, University of Texas Southwestern Medical Center, Dallas, Texas, USA
| | | | | | | | | |
Collapse
|
43
|
Kooli A, Kermorvant-Duchemin E, Sennlaub F, Bossolasco M, Hou X, Honoré JC, Dennery PA, Sapieha P, Varma D, Lachapelle P, Zhu T, Tremblay S, Hardy P, Jain K, Balazy M, Chemtob S. trans-Arachidonic acids induce a heme oxygenase-dependent vasorelaxation of cerebral microvasculature. Free Radic Biol Med 2008; 44:815-25. [PMID: 18082639 DOI: 10.1016/j.freeradbiomed.2007.11.006] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/22/2007] [Revised: 10/24/2007] [Accepted: 11/07/2007] [Indexed: 10/22/2022]
Abstract
Nitrative stress is an important regulator of vascular tone. We have recently described that trans-arachidonic acids (TAA) are major products of NO(2)(.)-mediated isomerization of arachidonic acid in cell membranes and that nitrative stress increases TAA levels leading to neural microvascular degeneration. In the present study, we explored whether TAA exert acute effects on neuromicrovascular tone and investigated potential mechanisms thereof. TAA induced an endothelium-dependent vasorelaxation of rat brain pial microvasculature. This vasorelaxation was independent of nitric oxide, prostanoids, lipoxygenase products, and CYP(450) metabolite trans-hydroxyeicosatetraenoic acids. However, inhibition of heme oxygenase (using zinc protoporphyrin IX) and of dependent soluble guanylate cyclase (sGC; using ODQ) significantly diminished (by approximately 70%) the TAA-induced vasorelaxation. Consistent with these findings, TAA stimulated heme oxygenase (HO)-2-dependent bilirubin (using siRNA HO-2) and cGMP formation, and the HO product carbon monoxide (using CO-releasing CORM-2) reproduced the sGC-dependent cGMP formation and vasorelaxation. Further exploration revealed that TAA-induced vasorelaxation and bilirubin formation (HO activation) were nearly abrogated by large-conductance calcium-dependent potassium channels (BK(Ca)) (using TEA and iberiotoxin). Opening of BK(Ca) with the selective activator NS1619 induced a concentration-dependent vasorelaxation, which was inhibited by HO and sGC inhibitors. Coimmunoprecipitation suggested a molecular complex interaction between BK(Ca) and HO-2 (but not HO-1). Collectively, these findings identify new properties of TAA, specifically cerebral vasorelaxation through interactive activation of BK(Ca) with HO-2 and, in turn, sGC. Our findings provide new insights into the characterization of nitrative stress-derived TAA products, by showing they can act as acute mediators of nitrative stress on neurovascular tone.
Collapse
Affiliation(s)
- Amna Kooli
- Department of Paediatrics, Research Center of Hôpital Ste-Justine, Montréal, Quebec, Canada
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
44
|
Hyperoxia causes maturation-dependent cell death in the developing white matter. J Neurosci 2008; 28:1236-45. [PMID: 18234901 DOI: 10.1523/jneurosci.3213-07.2008] [Citation(s) in RCA: 140] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023] Open
Abstract
Periventricular leukomalacia is the predominant injury in the preterm infant leading to cerebral palsy. Oxygen exposure may be an additional cause of brain injury in these infants. In this study, we investigated pathways of maturation-dependent oligodendrocyte (OL) death induced by hyperoxia in vitro and in vivo. Developing and mature OLs were subjected to 80% oxygen (0-24 h). Lactate dehydrogenase (LDH) assay was used to assess cell viability. Furthermore, 3-, 6-, and 10-d-old rat pups were subjected to 80% oxygen (24 h), and their brains were processed for myelin basic protein staining. Significant cell death was detected after 6-24 h incubation in 80% oxygen in pre-OLs (O4+,O1-), but not in mature OLs (MBP+). Cell death was executed by a caspase-dependent apoptotic pathway and could be blocked by the pan-caspase inhibitor zVAD-fmk. Overexpression of BCL2 (Homo sapiens B-cell chronic lymphocytic leukemia/lymphoma 2) significantly reduced apoptosis. Accumulation of superoxide and generation of reactive oxygen species (ROS) were detected after 2 h of oxygen exposure. Lipoxygenase inhibitors 2,3,5-trimethyl-6-(12-hydroxy-5-10-dodecadiynyl-1,4-benzoquinone and N-benzyl-N-hydroxy-5-phenylpentamide fully protected the cells from oxidative injury. Overexpression of superoxide dismutase (SOD1) dramatically increased injury to pre-OLs but not to mature OLs. We extended these studies by testing the effects of hyperoxia on neonatal white matter. Postnatal day 3 (P3) and P6 rats, but not P10 pups, showed bilateral reduction in MBP (myelin basic protein) expression with 24 h exposure to 80% oxygen. Hyperoxia causes oxidative stress and triggers maturation-dependent apoptosis in pre-OLs, which involves the generation of ROS and caspase activation, and leads to white matter injury in the neonatal rat brain. These observations may be relevant to white matter injury observed in premature infants.
Collapse
|
45
|
Mechanisms underlying developmental programming of elevated blood pressure and vascular dysfunction: evidence from human studies and experimental animal models. Clin Sci (Lond) 2008; 114:1-17. [PMID: 18047465 DOI: 10.1042/cs20070113] [Citation(s) in RCA: 134] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Cardiovascular-related diseases are the leading cause of death in the world in both men and women. In addition to the environmental and genetic factors, early life conditions are now also considered important contributing elements to these pathologies. The concept of 'fetal' or 'developmental' origins of adult diseases has received increased recognition over the last decade, yet the mechanism by which altered perinatal environment can lead to dysfunction mostly apparent in the adult are incompletely understood. This review will focus on the mechanisms and pathways that epidemiological studies and experimental models have revealed underlying the adult cardiovascular phenotype dictated by the perinatal experience, as well as the probable key causal or triggering elements. Programmed elevated blood pressure in the adult human or animal is characterized by vascular dysfunction and microvascular rarefaction. Developmental mechanisms that have been more extensively studied include glucocorticoid exposure, the role of the kidneys and the renin-angiotensin system. Other pathophysiological pathways have been explored, such as the role of the brain and the sympathetic nervous system, oxidative stress and epigenetic changes. As with many complex diseases, a unifying hypothesis linking the perinatal environment to elevated blood pressure and vascular dysfunction in later life cannot be presumed, and a better understanding of those mechanisms is critical before clinical trials of preventive or 'deprogramming' measures can be designed.
Collapse
|
46
|
Hoehn T, Janssen S, Mani AR, Brauers G, Moore KP, Schadewaldt P, Mayatepek E. Urinary excretion of the nitrotyrosine metabolite 3-nitro-4-hydroxyphenylacetic acid in preterm and term infants. Neonatology 2008; 93:73-6. [PMID: 17684421 DOI: 10.1159/000106783] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/03/2007] [Accepted: 05/30/2007] [Indexed: 11/19/2022]
Abstract
BACKGROUND Newborn infants are exposed to various sources of oxidative and/or nitrative stress, which refers to either oxidation and/or nitration of endogenous proteins including loss of their original function. Nitrative stress is predominantly caused following synthesis of peroxynitrite. Particularly preterm infants with immature defense mechanisms against free radical injury appear at risk. OBJECTIVE To test the feasibility of quantifying the degradation products of the peroxynitrite marker nitrotyrosine [3-nitro-4-hydroxyphenylacetic acid (NHPA) and para-hydroxyphenylacetic acid (PHPA)] in neonatal urine samples. METHODS NHPA and PHPA were determined by gas chromatography/mass spectroscopy in urinary samples of preterm and term infants (mean gestational age = 28.4 and 39.6 weeks, respectively). RESULTS The urinary NHPA levels were lower in preterm infants in comparison with term infants. When the NHPA levels were adjusted to the urinary PHPA levels, no differences were found between the two groups. CONCLUSIONS Nitrotyrosine can be quantified in urinary samples of even the most immature infants. Nitration of endogenous PHPA in the gastrointestinal tract of term infants may have masked potentially higher levels of NHPA in preterm infants.
Collapse
Affiliation(s)
- Thomas Hoehn
- Neonatology and Paediatric Intensive Care Medicine, Department of General Paediatrics, Heinrich Heine University, Dusseldorf, Germany.
| | | | | | | | | | | | | |
Collapse
|