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Tran NT, Penny TR, Chan KY, Tang T, Papagianis PC, Sepehrizadeh T, Nekkanti L, Zahra VA, Pham Y, Yawno T, Nitsos I, Kelly SB, Thiel AM, de Veer M, Alahmari DM, Fahey MC, Jenkin G, Miller SL, Galinsky R, Polglase GR, McDonald CA. Early administration of umbilical cord blood cells following brief high tidal volume ventilation in preterm sheep: a cautionary tale. J Neuroinflammation 2024; 21:121. [PMID: 38720368 PMCID: PMC11077893 DOI: 10.1186/s12974-024-03053-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2024] [Accepted: 02/23/2024] [Indexed: 05/12/2024] Open
Abstract
BACKGROUND Umbilical cord blood (UCB) cells are a promising treatment for preterm brain injury. Access to allogeneic sources of UCB cells offer the potential for early administration to optimise their therapeutic capacities. As preterm infants often require ventilatory support, which can contribute to preterm brain injury, we investigated the efficacy of early UCB cell administration following ventilation to reduce white matter inflammation and injury. METHODS Preterm fetal sheep (0.85 gestation) were randomly allocated to no ventilation (SHAM; n = 5) or 15 min ex utero high tidal volume ventilation. One hour following ventilation, fetuses were randomly allocated to i.v. administration of saline (VENT; n = 7) or allogeneic term-derived UCB cells (24.5 ± 5.0 million cells/kg; VENT + UCB; n = 7). Twenty-four hours after ventilation, lambs were delivered for magnetic resonance imaging and post-mortem brain tissue collected. Arterial plasma was collected throughout the experiment for cytokine analyses. To further investigate the results from the in vivo study, mononuclear cells (MNCs) isolated from human UCB were subjected to in vitro cytokine-spiked culture medium (TNFα and/or IFNγ; 10 ng/mL; n = 3/group) for 16 h then supernatant and cells collected for protein and mRNA assessments respectively. RESULTS In VENT + UCB lambs, systemic IFNγ levels increased and by 24 h, there was white matter neuroglial activation, vascular damage, reduced oligodendrocytes, and increased average, radial and mean diffusivity compared to VENT and SHAM. No evidence of white matter inflammation or injury was present in VENT lambs, except for mRNA downregulation of OCLN and CLDN1 compared to SHAM. In vitro, MNCs subjected to TNFα and/or IFNγ displayed both pro- and anti-inflammatory characteristics indicated by changes in cytokine (IL-18 & IL-10) and growth factor (BDNF & VEGF) gene and protein expression compared to controls. CONCLUSIONS UCB cells administered early after brief high tidal volume ventilation in preterm fetal sheep causes white matter injury, and the mechanisms underlying these changes are likely dysregulated responses of the UCB cells to the degree of injury/inflammation already present. If immunomodulatory therapies such as UCB cells are to become a therapeutic strategy for preterm brain injury, especially after ventilation, our study suggests that the inflammatory state of the preterm infant should be considered when timing UCB cells administration.
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Affiliation(s)
- Nhi T Tran
- The Ritchie Centre, Hudson Institute of Medical Research, Clayton, VIC, Australia.
- Department of Obstetrics and Gynaecology, Monash University, Clayton, VIC, Australia.
| | - Tayla R Penny
- The Ritchie Centre, Hudson Institute of Medical Research, Clayton, VIC, Australia
- Department of Obstetrics and Gynaecology, Monash University, Clayton, VIC, Australia
| | - Kyra Yy Chan
- The Ritchie Centre, Hudson Institute of Medical Research, Clayton, VIC, Australia
- Department of Obstetrics and Gynaecology, Monash University, Clayton, VIC, Australia
| | - Tanya Tang
- The Ritchie Centre, Hudson Institute of Medical Research, Clayton, VIC, Australia
- Department of Obstetrics and Gynaecology, Monash University, Clayton, VIC, Australia
| | - Paris C Papagianis
- Department of Pharmacology, Biomedicine Discovery Institute, Monash University, Clayton, VIC, Australia
| | - Tara Sepehrizadeh
- Monash Biomedical Imaging, Monash University, Clayton, VIC, Australia
| | - Lakshmi Nekkanti
- The Ritchie Centre, Hudson Institute of Medical Research, Clayton, VIC, Australia
| | - Valerie A Zahra
- The Ritchie Centre, Hudson Institute of Medical Research, Clayton, VIC, Australia
| | - Yen Pham
- The Ritchie Centre, Hudson Institute of Medical Research, Clayton, VIC, Australia
| | - Tamara Yawno
- The Ritchie Centre, Hudson Institute of Medical Research, Clayton, VIC, Australia
- Department of Obstetrics and Gynaecology, Monash University, Clayton, VIC, Australia
- Department of Paediatrics, Monash University, Clayton, VIC, Australia
| | - Ilias Nitsos
- The Ritchie Centre, Hudson Institute of Medical Research, Clayton, VIC, Australia
| | - Sharmony B Kelly
- The Ritchie Centre, Hudson Institute of Medical Research, Clayton, VIC, Australia
- Department of Obstetrics and Gynaecology, Monash University, Clayton, VIC, Australia
| | - Alison M Thiel
- The Ritchie Centre, Hudson Institute of Medical Research, Clayton, VIC, Australia
| | - Michael de Veer
- Monash Biomedical Imaging, Monash University, Clayton, VIC, Australia
| | - Dhafer M Alahmari
- Monash Biomedical Imaging, Monash University, Clayton, VIC, Australia
- Monash Biomedicine Discovery Institute and Department of Medical Imaging and Radiation Sciences, Monash University, Clayton, VIC, Australia
- Department of Diagnostic Imaging, Kind Saud Medical City, Riyadh, Saudi Arabia
| | - Michael C Fahey
- Department of Paediatrics, Monash University, Clayton, VIC, Australia
| | - Graham Jenkin
- The Ritchie Centre, Hudson Institute of Medical Research, Clayton, VIC, Australia
- Department of Obstetrics and Gynaecology, Monash University, Clayton, VIC, Australia
| | - Suzanne L Miller
- The Ritchie Centre, Hudson Institute of Medical Research, Clayton, VIC, Australia
- Department of Obstetrics and Gynaecology, Monash University, Clayton, VIC, Australia
| | - Robert Galinsky
- The Ritchie Centre, Hudson Institute of Medical Research, Clayton, VIC, Australia
- Department of Obstetrics and Gynaecology, Monash University, Clayton, VIC, Australia
| | - Graeme R Polglase
- The Ritchie Centre, Hudson Institute of Medical Research, Clayton, VIC, Australia.
- Department of Obstetrics and Gynaecology, Monash University, Clayton, VIC, Australia.
| | - Courtney A McDonald
- The Ritchie Centre, Hudson Institute of Medical Research, Clayton, VIC, Australia.
- Department of Obstetrics and Gynaecology, Monash University, Clayton, VIC, Australia.
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Chan KYY, Tran NT, Papagianis PC, Zahra VA, Nitsos I, Moxham AM, LaRosa DA, McDonald C, Miller SL, Galinsky R, Alahmari DM, Stojanovska V, Polglase GR. Investigating Pathways of Ventilation Induced Brain Injury on Cerebral White Matter Inflammation and Injury After 24 h in Preterm Lambs. Front Physiol 2022; 13:904144. [PMID: 35860659 PMCID: PMC9289398 DOI: 10.3389/fphys.2022.904144] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2022] [Accepted: 06/13/2022] [Indexed: 11/13/2022] Open
Abstract
Initiation of respiratory support in the delivery room increases the risk and severity of brain injury in preterm neonates through two major pathways: an inflammatory pathway and a haemodynamic pathway. The relative contribution of each pathway on preterm brain injury is not known. We aimed to assess the role of the inflammatory and haemodynamic pathway on ventilation-induced brain injury (VIBI) in the preterm lamb. Fetal lambs (125 ± 1 day gestation) were exteriorised, instrumented and ventilated with a high tidal-volume (VT) injurious strategy for 15 min either with placental circulation intact to induce the inflammatory pathway only (INJINF; n = 7) or umbilical cord occluded to induce both the inflammatory and haemodynamic pathways (INJINF+HAE; n = 7). Sham controls were exteriorised but not ventilated (SHAM; n = 5) while unoperated controls (UNOP; n = 7) did not undergo fetal instrumentation. Fetuses were returned in utero following intervention and the ewe allowed to recover. Arterial blood gases and plasma were sampled periodically. Twenty-four hours following intervention, lambs were delivered and maintained on non-injurious ventilation for ∼40 min then brains were collected post-mortem for immunohistochemistry and RT-qPCR to assess inflammation, vascular pathology and cell death within white matter regions. Compared to INJINF lambs, INJINF+HAE lambs achieved a consistently higher VT during injurious ventilation and carotid blood flow was significantly lower than baseline by the end of ventilation. Throughout the 24 h recovery period, systemic arterial IL-6 levels of INJINF+HAE lambs were significantly higher than SHAM while there was no difference between INJINF and SHAM animals. At 24 h, mRNA expression levels of pro-inflammatory cytokines, tight junction proteins, markers of cell death, and histological injury indices of gliosis, blood vessel protein extravasation, oligodendrocyte injury and cell death were not different between groups. Injurious ventilation, irrespective of strategy, did not increase brain inflammation or injury 24 h later when compared to control animals. However, the haemodynamic pathway did influence carotid blood flow adaptations during injurious ventilation and increased systemic arterial IL-6 that may underlie long-term pathology. Future studies are required to further characterise the pathways and their long-term effects on VIBI.
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Affiliation(s)
- Kyra YY Chan
- The Ritchie Centre, Hudson Institute of Medical Research, Clayton, VIC, Australia
- Department of Obstetrics and Gynaecology, Monash University, Clayton, VIC, Australia
| | - Nhi T. Tran
- The Ritchie Centre, Hudson Institute of Medical Research, Clayton, VIC, Australia
- Department of Obstetrics and Gynaecology, Monash University, Clayton, VIC, Australia
| | - Paris C. Papagianis
- The Ritchie Centre, Hudson Institute of Medical Research, Clayton, VIC, Australia
| | - Valerie A. Zahra
- The Ritchie Centre, Hudson Institute of Medical Research, Clayton, VIC, Australia
| | - Ilias Nitsos
- The Ritchie Centre, Hudson Institute of Medical Research, Clayton, VIC, Australia
- Department of Obstetrics and Gynaecology, Monash University, Clayton, VIC, Australia
| | - Alison M. Moxham
- The Ritchie Centre, Hudson Institute of Medical Research, Clayton, VIC, Australia
| | - Domenic A. LaRosa
- The Ritchie Centre, Hudson Institute of Medical Research, Clayton, VIC, Australia
- Department of Obstetrics and Gynaecology, Monash University, Clayton, VIC, Australia
| | - Courtney McDonald
- The Ritchie Centre, Hudson Institute of Medical Research, Clayton, VIC, Australia
- Department of Obstetrics and Gynaecology, Monash University, Clayton, VIC, Australia
| | - Suzanne L. Miller
- The Ritchie Centre, Hudson Institute of Medical Research, Clayton, VIC, Australia
- Department of Obstetrics and Gynaecology, Monash University, Clayton, VIC, Australia
| | - Robert Galinsky
- The Ritchie Centre, Hudson Institute of Medical Research, Clayton, VIC, Australia
- Department of Obstetrics and Gynaecology, Monash University, Clayton, VIC, Australia
| | - Dhafer M. Alahmari
- Monash Biomedicine Discovery Institute and Department of Medical Imaging and Radiation Sciences, Monash University, Clayton, VIC, Australia
- Monash Biomedical Imaging, Monash University, Clayton, VIC, Australia
- Department of Diagnostic Imaging, King Saud Medical City, Riyadh, Saudi Arabia
| | - Vanesa Stojanovska
- The Ritchie Centre, Hudson Institute of Medical Research, Clayton, VIC, Australia
- Department of Obstetrics and Gynaecology, Monash University, Clayton, VIC, Australia
| | - Graeme R. Polglase
- The Ritchie Centre, Hudson Institute of Medical Research, Clayton, VIC, Australia
- Department of Obstetrics and Gynaecology, Monash University, Clayton, VIC, Australia
- *Correspondence: Graeme R. Polglase,
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Gamage TKJB, Fraser M. The Role of Extracellular Vesicles in the Developing Brain: Current Perspective and Promising Source of Biomarkers and Therapy for Perinatal Brain Injury. Front Neurosci 2021; 15:744840. [PMID: 34630028 PMCID: PMC8498217 DOI: 10.3389/fnins.2021.744840] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2021] [Accepted: 08/23/2021] [Indexed: 12/12/2022] Open
Abstract
This comprehensive review focuses on our current understanding of the proposed physiological and pathological functions of extracellular vesicles (EVs) in the developing brain. Furthermore, since EVs have attracted great interest as potential novel cell-free therapeutics, we discuss advances in the knowledge of stem cell- and astrocyte-derived EVs in relation to their potential for protection and repair following perinatal brain injury. This review identified 13 peer-reviewed studies evaluating the efficacy of EVs in animal models of perinatal brain injury; 12/13 utilized mesenchymal stem cell-derived EVs (MSC-EVs) and 1/13 utilized astrocyte-derived EVs. Animal model, method of EV isolation and size, route, timing, and dose administered varied between studies. Notwithstanding, EV treatment either improved and/or preserved perinatal brain structures both macroscopically and microscopically. Additionally, EV treatment modulated inflammatory responses and improved brain function. Collectively this suggests EVs can ameliorate, or repair damage associated with perinatal brain injury. These findings warrant further investigation to identify the optimal cell numbers, source, and dosage regimens of EVs, including long-term effects on functional outcomes.
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Affiliation(s)
- Teena K J B Gamage
- Department of Physiology, The University of Auckland, Auckland, New Zealand
| | - Mhoyra Fraser
- Department of Physiology, The University of Auckland, Auckland, New Zealand
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4
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Menegaux A, Meng C, Bäuml JG, Berndt MT, Hedderich DM, Schmitz-Koep B, Schneider S, Nuttall R, Zimmermann J, Daamen M, Zimmer C, Boecker H, Bartmann P, Wolke D, Sorg C. Aberrant cortico-thalamic structural connectivity in premature-born adults. Cortex 2021; 141:347-362. [PMID: 34126289 DOI: 10.1016/j.cortex.2021.04.009] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2020] [Revised: 02/15/2021] [Accepted: 04/26/2021] [Indexed: 12/29/2022]
Abstract
Premature birth is associated with alterations in brain structure, particularly in white matter. Among white matter, alterations in cortico-thalamic connections are present in premature-born infants, and they have been suggested both to last until adulthood and to contribute to impaired cognitive functions. To test these hypotheses, 70 very premature-born adults and 67 full-term controls underwent cognitive testing and diffusion-weighted imaging. Each cortical hemisphere was parcellated into six lobes, from which probabilistic tractography was performed to the thalamus. Connection probability was chosen as metric of structural connectivity. We found increased cortico-thalamic connection probability between left prefrontal cortices and left medio-dorsal thalamus and reduced connection probability between bilateral temporal cortices and bilateral anterior thalami in very premature-born adults. Aberrant prefronto- and temporo-thalamic connection probabilities were correlated with birth weight and days on ventilation, respectively, supporting the suggestion that these connectivity changes relate with the degree of prematurity. Moreover, an increase in left prefronto-thalamic connection probability also correlated with lower verbal comprehension index indicating its relevance for verbal cognition. Together, our results demonstrate that cortico-thalamic structural connectivity is aberrant in premature-born adults, with these changes being linked with impairments in verbal cognitive abilities. Due to corresponding findings in infants, data suggest aberrant development of cortico-thalamic connectivity after premature birth with lasting effects into adulthood.
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Affiliation(s)
- Aurore Menegaux
- Department of Neuroradiology, School of Medicine, Technical University of Munich, Munich, Germany; TUM Neuroimaging Center, School of Medicine, Technical University of Munich, Munich, Germany.
| | - Chun Meng
- Department of Neuroradiology, School of Medicine, Technical University of Munich, Munich, Germany; TUM Neuroimaging Center, School of Medicine, Technical University of Munich, Munich, Germany; The Clinical Hospital of Chengdu Brain Science Institute, MOE Key Laboratory for Neuroinformation, Center for Information in Medicine, School of Life Science and Technology, University of Electronic Science and Technology of China, Chengdu, China
| | - Josef G Bäuml
- Department of Neuroradiology, School of Medicine, Technical University of Munich, Munich, Germany; TUM Neuroimaging Center, School of Medicine, Technical University of Munich, Munich, Germany
| | - Maria T Berndt
- Department of Neuroradiology, School of Medicine, Technical University of Munich, Munich, Germany; TUM Neuroimaging Center, School of Medicine, Technical University of Munich, Munich, Germany
| | - Dennis M Hedderich
- Department of Neuroradiology, School of Medicine, Technical University of Munich, Munich, Germany; TUM Neuroimaging Center, School of Medicine, Technical University of Munich, Munich, Germany
| | - Benita Schmitz-Koep
- Department of Neuroradiology, School of Medicine, Technical University of Munich, Munich, Germany; TUM Neuroimaging Center, School of Medicine, Technical University of Munich, Munich, Germany
| | - Sebastian Schneider
- Department of Neuroradiology, School of Medicine, Technical University of Munich, Munich, Germany; TUM Neuroimaging Center, School of Medicine, Technical University of Munich, Munich, Germany
| | - Rachel Nuttall
- Department of Neuroradiology, School of Medicine, Technical University of Munich, Munich, Germany; TUM Neuroimaging Center, School of Medicine, Technical University of Munich, Munich, Germany
| | - Juliana Zimmermann
- Department of Neuroradiology, School of Medicine, Technical University of Munich, Munich, Germany; TUM Neuroimaging Center, School of Medicine, Technical University of Munich, Munich, Germany
| | - Marcel Daamen
- Functional Neuroimaging Group, Department of Diagnostic and Interventional Radiology, University Hospital Bonn, Bonn, Germany; Department of Neonatology, University Hospital Bonn, Bonn, Germany
| | - Claus Zimmer
- Department of Neuroradiology, School of Medicine, Technical University of Munich, Munich, Germany; TUM Neuroimaging Center, School of Medicine, Technical University of Munich, Munich, Germany
| | - Henning Boecker
- Functional Neuroimaging Group, Department of Diagnostic and Interventional Radiology, University Hospital Bonn, Bonn, Germany
| | - Peter Bartmann
- Department of Neonatology, University Hospital Bonn, Bonn, Germany
| | - Dieter Wolke
- Department of Psychology, University of Warwick, Coventry, UK; Warwick Medical School, University of Warwick, Coventry, UK
| | - Christian Sorg
- Department of Neuroradiology, School of Medicine, Technical University of Munich, Munich, Germany; TUM Neuroimaging Center, School of Medicine, Technical University of Munich, Munich, Germany; Department of Psychiatry, School of Medicine, Technical University of Munich, Munich, Germany
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5
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O'Connell AB, Kuchel TR, Perumal SR, Sherwood V, Neumann D, Finnie JW, Hemsley KM, Morton AJ. Longitudinal Magnetic Resonance Spectroscopy and Diffusion Tensor Imaging in Sheep (Ovis aries) With Quinolinic Acid Lesions of the Striatum: Time-Dependent Recovery of N-Acetylaspartate and Fractional Anisotropy. J Neuropathol Exp Neurol 2021; 79:1084-1092. [PMID: 32743645 DOI: 10.1093/jnen/nlaa053] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2019] [Indexed: 12/19/2022] Open
Abstract
We created an excitotoxic striatal lesion model of Huntington disease (HD) in sheep, using the N-methyl-d-aspartate receptor agonist, quinolinic acid (QA). Sixteen sheep received a bolus infusion of QA (75 µL, 180 mM) or saline, first into the left and then (4 weeks later) into the right striatum. Magnetic resonance spectroscopy (MRS) and diffusion tensor imaging (DTI) of the striata were performed. Metabolite concentrations and fractional anisotropy (FA) were measured at baseline, acutely (1 week after each surgery) and chronically (5 weeks or greater after the surgeries). There was a significant decrease in the neuronal marker N-acetylaspartate (NAA) and in FA in acutely lesioned striata of the QA-lesioned sheep, followed by a recovery of NAA and FA in the chronically lesioned striata. NAA level changes indicate acute death and/or impairment of neurons immediately after surgery, with recovery of reversibly impaired neurons over time. The change in FA values of the QA-lesioned striata is consistent with acute structural disruption, followed by re-organization and glial cell infiltration with time. Our study demonstrates that MRS and DTI changes in QA-sheep are consistent with HD-like pathology shown in other model species and that the MR investigations can be performed in sheep using a clinically relevant human 3T MRI scanner.
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Affiliation(s)
- Adam B O'Connell
- Pre-Clinical, Imaging and Research Laboratories (PIRL), South Australia Health and Medical Research Institute (SAHMRI), Adelaide, South Australia.,School of Medical Specialties, University of Adelaide, Adelaide, South Australia
| | - Timothy R Kuchel
- Pre-Clinical, Imaging and Research Laboratories (PIRL), South Australia Health and Medical Research Institute (SAHMRI), Adelaide, South Australia
| | - Sunthara R Perumal
- Pre-Clinical, Imaging and Research Laboratories (PIRL), South Australia Health and Medical Research Institute (SAHMRI), Adelaide, South Australia
| | | | - Daniel Neumann
- Childhood Dementia Research Group, Hopwood Centre for Neurobiology, SAHMRI, Adelaide, Australia.,Childhood Dementia Research Group, College of Medicine and Public Health, Flinders University, Adelaide, Australia
| | - John W Finnie
- Discipline of Anatomy and Pathology, Adelaide Medical School, University of Adelaide and SA Pathology, Adelaide, Australia
| | - Kim M Hemsley
- Childhood Dementia Research Group, Hopwood Centre for Neurobiology, SAHMRI, Adelaide, Australia.,Childhood Dementia Research Group, College of Medicine and Public Health, Flinders University, Adelaide, Australia
| | - A Jennifer Morton
- Department of Physiology, Development and Neuroscience, Cambridge University, Cambridge, UK
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6
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Tidal volume measurements in the delivery room in preterm infants requiring positive pressure ventilation via endotracheal tube-feasibility study. J Perinatol 2021; 41:1930-1935. [PMID: 34112962 PMCID: PMC8191447 DOI: 10.1038/s41372-021-01113-7] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/08/2021] [Revised: 05/05/2021] [Accepted: 05/18/2021] [Indexed: 01/31/2023]
Abstract
OBJECTIVE Current delivery room (DR) resuscitation utilizes pressure-limited devices without tidal volume (TV) measurements. Clinicians use chest expansion as a surrogate, which is a poor indicator of TV. TV in early life can be highly variable due to rapidly changing lung compliance. Our objectives were to assess feasibility of measuring TV in DR, and to report the generated TV in intubated patients. STUDY DESIGN Prospective, observational, feasibility study in infants <32 weeks GA and intubated in DR. TV was measured using a respiratory function monitor. RESULT Ten infants with mean GA 23.9(±1.5) weeks and mean BW 618.5(±155) gram were included. Total of 178 min (mean 17.8 min/patient) with 8175 individual breaths (mean 817.5 breaths/patient) were analyzed. Goal TV of 4-6 ml/kg was provided 23.5% of times with high TV (>6 ml/kg) provided 47.7% of times. CONCLUSION TV measurement in DR is feasible. It is associated with high intra and inter-patient variability.
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7
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Chan KYY, Miller SL, Schmölzer GM, Stojanovska V, Polglase GR. Respiratory Support of the Preterm Neonate: Lessons About Ventilation-Induced Brain Injury From Large Animal Models. Front Neurol 2020; 11:862. [PMID: 32922358 PMCID: PMC7456830 DOI: 10.3389/fneur.2020.00862] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2020] [Accepted: 07/07/2020] [Indexed: 11/25/2022] Open
Abstract
Many preterm neonates require mechanical ventilation which increases the risk of cerebral inflammation and white matter injury in the immature brain. In this review, we discuss the links between ventilation and brain injury with a focus on the immediate period after birth, incorporating respiratory support in the delivery room and subsequent mechanical ventilation in the neonatal intensive care unit. This review collates insight from large animal models in which acute injurious ventilation and prolonged periods of ventilation have been used to create clinically relevant brain injury patterns. These models are valuable resources in investigating the pathophysiology of ventilation-induced brain injury and have important translational implications. We discuss the challenges of reconciling lung and brain maturation in commonly used large animal models. A comprehensive understanding of ventilation-induced brain injury is necessary to guide the way we care for preterm neonates, with the goal to improve their neurodevelopmental outcomes.
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Affiliation(s)
- Kyra Y Y Chan
- The Ritchie Centre, Hudson Institute of Medical Research, Clayton, VIC, Australia.,Department of Obstetrics and Gynecology, Monash University, Clayton, VIC, Australia
| | - Suzanne L Miller
- The Ritchie Centre, Hudson Institute of Medical Research, Clayton, VIC, Australia.,Department of Obstetrics and Gynecology, Monash University, Clayton, VIC, Australia
| | - Georg M Schmölzer
- Neonatal Research Unit, Centre for the Studies of Asphyxia and Resuscitation, Royal Alexandra Hospital, Edmonton, AB, Canada.,Department of Pediatrics, University of Alberta, Edmonton, AB, Canada
| | - Vanesa Stojanovska
- The Ritchie Centre, Hudson Institute of Medical Research, Clayton, VIC, Australia.,Department of Obstetrics and Gynecology, Monash University, Clayton, VIC, Australia
| | - Graeme R Polglase
- The Ritchie Centre, Hudson Institute of Medical Research, Clayton, VIC, Australia.,Department of Obstetrics and Gynecology, Monash University, Clayton, VIC, Australia
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8
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Cannavò L, Rulli I, Falsaperla R, Corsello G, Gitto E. Ventilation, oxidative stress and risk of brain injury in preterm newborn. Ital J Pediatr 2020; 46:100. [PMID: 32703261 PMCID: PMC7376314 DOI: 10.1186/s13052-020-00852-1] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/21/2020] [Accepted: 06/17/2020] [Indexed: 11/11/2022] Open
Abstract
Preterm infants have an increased risk of cognitive and behavioral deficits and cerebral palsy compared to term born babies. Especially before 32 weeks of gestation, infants may require respiratory support, but at the same time, ventilation is known to induce oxidative stress, increasing the risk of brain injury. Ventilation may cause brain damage through two pathways: localized cerebral inflammatory response and hemodynamic instability. During ventilation, the most important causes of pro-inflammatory cytokine release are oxygen toxicity, barotrauma and volutrauma. The purpose of this review was to analyze the mechanism of ventilation-induced lung injury (VILI) and the relationship between brain injury and VILI in order to provide the safest possible respiratory support to a premature baby. As gentle ventilation from the delivery room is needed to reduce VILI, it is recommended to start ventilation with 21–30% oxygen, prefer a non-invasive respiratory approach and, if mechanical ventilation is required, prefer low Positive End-Expiratory Pressure and tidal volume.
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Affiliation(s)
- Laura Cannavò
- Department of Human Pathology of Adulthood and Childhood, University of Messina, UOC di Pediatria, Pad. NI, 3° piano, AOU Policlinico Gaetano Martino, Via Consolare Valeria, 1, 98125, Messina, Italy.
| | - Immacolata Rulli
- Department of Human Pathology of Adulthood and Childhood, University of Messina, Messina, Italy
| | - Raffaele Falsaperla
- Department of Paediatrics, Policlinico-Vittorio Emanuele University Hospital, Catania, Italy
| | - Giovanni Corsello
- Department of Maternal and Child Health, University of Palermo, Palermo, Italy
| | - Eloisa Gitto
- Department of Human Pathology of Adulthood and Childhood, University of Messina, Messina, Italy
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9
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Yates NJ, Feindel KW, Mehnert A, Beare R, Quick S, Blache D, Pillow JJ, Hunt RW. Ex Vivo MRI Analytical Methods and Brain Pathology in Preterm Lambs Treated with Postnatal Dexamethasone †. Brain Sci 2020; 10:brainsci10040211. [PMID: 32260193 PMCID: PMC7226431 DOI: 10.3390/brainsci10040211] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2020] [Revised: 03/26/2020] [Accepted: 04/01/2020] [Indexed: 01/22/2023] Open
Abstract
Postnatal glucocorticoids such as dexamethasone are effective in promoting lung development in preterm infants, but are prescribed cautiously due to concerns of neurological harm. We developed an analysis pipeline for post-mortem magnetic resonance imaging (MRI) to assess brain development and hence the neurological safety profile of postnatal dexamethasone in preterm lambs. Lambs were delivered via caesarean section at 129 days’ (d) gestation (full term ≈ 150 d) with saline-vehicle control (Saline, n = 9), low-dose tapered dexamethasone (cumulative dose = 0.75 mg/kg, n = 8), or high-dose tapered dexamethasone (cumulative dose = 2.67 mg/kg, n = 8), for seven days. Naïve fetal lambs (136 d gestation) were used as end-point maturation controls. The left-brain hemispheres were immersion-fixed in 10 % formalin (24 h), followed by paraformaldehyde (>6 months). Image sequences were empirically optimized for T1- and T2-weighted MRI and analysed using accessible methods. Spontaneous lesions detected in the white matter of the frontal cortex, temporo-parietal cortex, occipital lobe, and deep to the parahippocampal gyrus were confirmed with histology. Neither postnatal dexamethasone treatment nor gestation showed any associations with lesion incidence, frontal cortex (total, white, or grey matter) or hippocampal volume (all p > 0.05). Postnatal dexamethasone did not appear to adversely affect neurodevelopment. Our post-mortem MRI analysis pipeline is suitable for other animal models of brain development.
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Affiliation(s)
- Nathanael J. Yates
- School of Human Sciences, University of Western Australia, Perth 6009, Australia;
- Queensland Brain Institute, University of Queensland, Brisbane 4072, Australia
- Correspondence: ; Tel.: +61-7-344-66361
| | - Kirk W. Feindel
- Centre for Microscopy, Characterisation and Analysis, University of Western Australia, Perth 6009, Australia; (K.W.F.); (A.M.); (S.Q.)
- School of Biomedical Sciences, University of Western Australia, Perth 6009, Australia
| | - Andrew Mehnert
- Centre for Microscopy, Characterisation and Analysis, University of Western Australia, Perth 6009, Australia; (K.W.F.); (A.M.); (S.Q.)
| | - Richard Beare
- Developmental Imaging, Murdoch Children’s Research Institute, Melbourne 3052, Australia;
- Department of Medicine, Monash University, Melbourne 3800, Australia
| | - Sophia Quick
- Centre for Microscopy, Characterisation and Analysis, University of Western Australia, Perth 6009, Australia; (K.W.F.); (A.M.); (S.Q.)
| | - Dominique Blache
- School of Agriculture and Environment, University of Western Australia, Perth 6009, Australia;
| | - J. Jane Pillow
- School of Human Sciences, University of Western Australia, Perth 6009, Australia;
| | - Rod W. Hunt
- Murdoch Children’s Research Institute, Melbourne 3052, Australia;
- Department of Paediatrics, University of Melbourne, Melbourne 3052, Australia
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10
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Stojanovska V, Barton SK, Tolcos M, Gill AW, Kluckow M, Miller SL, Zahra V, Hooper SB, Galinsky R, Polglase GR. The Effect of Antenatal Betamethasone on White Matter Inflammation and Injury in Fetal Sheep and Ventilated Preterm Lambs. Dev Neurosci 2019; 40:497-507. [PMID: 30840951 DOI: 10.1159/000496466] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2018] [Accepted: 12/20/2018] [Indexed: 11/19/2022] Open
Abstract
Antenatal administration of betamethasone (BM) is a common antecedent of preterm birth, but there is limited information about its impact on the acute evolution of preterm neonatal brain injury. We aimed to compare the effects of maternal BM in combination with mechanical ventilation on the white matter (WM) of late preterm sheep. At 0.85 of gestation, pregnant ewes were randomly assigned to receive intra-muscular (i.m.) saline (n = 9) or i.m. BM (n = 13). Lambs were delivered and unventilated controls (UVCSal, n = 4; UVCBM, n = 6) were humanely killed without intervention; ventilated lambs (VentSal, n = 5; VentBM, n = 7) were injuriously ventilated for 15 min, followed by conventional ventilation for 75 min. Cardiovascular and cerebral haemodynamics and oxygenation were measured continuously. The cerebral WM underwent assessment of inflammation and injury, and oxidative stress was measured in the cerebrospinal fluid (CSF). In the periventricular and subcortical WM tracts, the proportion of amoeboid (activated) microglia, the density of astrocytes, and the number of blood vessels with protein extravasation were higher in UVCBM than in UVCSal (p < 0.05 for all). During ventilation, tidal volume, mean arterial pressure, carotid blood flow, and oxygen delivery were higher in -VentBM lambs (p < 0.05 vs. VentSal). In the subcortical WM, microglial infiltration was increased in the VentSal group compared to UVCSal. The proportion of activated microglia and protein extravasation was higher in the VentBM group compared to VentSal within the periventricular and subcortical WM tracts (p < 0.05). CSF oxidative stress was increased in the VentBM group compared to UVCSal, UVCBM, and VentSal groups (p < 0.05). Antenatal BM was associated with inflammation and vascular permeability in the WM of late preterm fetal sheep. During the immediate neonatal period, the increased carotid perfusion and oxygen delivery in BM-treated lambs was associated with increased oxidative stress, microglial activation and microvascular injury.
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Affiliation(s)
- Vanesa Stojanovska
- The Ritchie Centre, Hudson Institute of Medical Research, Melbourne, Victoria, Australia.,Department of Obstetrics and Gynaecology, Monash University, Melbourne, Victoria, Australia
| | - Samantha K Barton
- The Ritchie Centre, Hudson Institute of Medical Research, Melbourne, Victoria, Australia.,Centre for Clinical Brain Sciences, University of Edinburgh, Edinburgh, United Kingdom
| | - Mary Tolcos
- School of Health and Biomedical Sciences, RMIT University, Bundoora, Victoria, Australia
| | - Andrew W Gill
- Centre for Neonatal Research and Education, The University of Western Australia, Crawley, Washington, Australia
| | - Martin Kluckow
- Department of Neonatal Medicine, Royal North Shore Hospital and University of Sydney, Sydney, New South Wales, Australia
| | - Suzanne L Miller
- The Ritchie Centre, Hudson Institute of Medical Research, Melbourne, Victoria, Australia.,Department of Obstetrics and Gynaecology, Monash University, Melbourne, Victoria, Australia
| | - Valerie Zahra
- The Ritchie Centre, Hudson Institute of Medical Research, Melbourne, Victoria, Australia
| | - Stuart B Hooper
- The Ritchie Centre, Hudson Institute of Medical Research, Melbourne, Victoria, Australia.,Department of Obstetrics and Gynaecology, Monash University, Melbourne, Victoria, Australia
| | - Robert Galinsky
- The Ritchie Centre, Hudson Institute of Medical Research, Melbourne, Victoria, Australia.,Department of Obstetrics and Gynaecology, Monash University, Melbourne, Victoria, Australia
| | - Graeme R Polglase
- The Ritchie Centre, Hudson Institute of Medical Research, Melbourne, Victoria, Australia, .,Department of Obstetrics and Gynaecology, Monash University, Melbourne, Victoria, Australia,
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11
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Martherus T, Oberthuer A, Dekker J, Hooper SB, McGillick EV, Kribs A, Te Pas AB. Supporting breathing of preterm infants at birth: a narrative review. Arch Dis Child Fetal Neonatal Ed 2019; 104:F102-F107. [PMID: 30049727 DOI: 10.1136/archdischild-2018-314898] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/31/2018] [Revised: 06/14/2018] [Accepted: 07/02/2018] [Indexed: 11/03/2022]
Abstract
Most very preterm infants have difficulty aerating their lungs and require respiratory support at birth. Currently in clinical practice, non-invasive ventilation in the form of continuous positive airway pressure (CPAP) and positive pressure ventilation (PPV) is applied via facemask. As most very preterm infants breathe weakly and unnoticed at birth, PPV is often administered. PPV is, however, frequently ineffective due to pressure settings, mask leak and airway obstruction. Meanwhile, high positive inspiratory pressures and spontaneous breathing coinciding with inflations can generate high tidal volumes. Evidence from preclinical studies demonstrates that high tidal volumes can be injurious to the lungs and brains of premature newborns. To reduce the need for PPV in the delivery room, it should be considered to optimise spontaneous breathing with CPAP. CPAP is recommended in guidelines and commonly used in the delivery room after a period of PPV, but little data is available on the ideal CPAP strategy and CPAP delivering devices and interfaces used in the delivery room. This narrative review summarises the currently available evidence for why PPV can be inadequate at birth and what is known about different CPAP strategies, devices and interfaces used the delivery room.
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Affiliation(s)
- Tessa Martherus
- Department of Paediatrics, Leiden University Medical Center, Leiden, Netherlands
| | - André Oberthuer
- Department of Neonatology, Children's Hospital University of Cologne, Cologne, Germany
| | - Janneke Dekker
- Department of Paediatrics, Leiden University Medical Center, Leiden, Netherlands
| | - Stuart B Hooper
- The Ritchie Centre, Hudson Institute for Medical Research, Clayton, Victoria, Australia.,Department of Obstetrics and Gynaecology, Monash University, Melbourne, Victoria, Australia
| | - Erin V McGillick
- The Ritchie Centre, Hudson Institute for Medical Research, Clayton, Victoria, Australia.,Department of Obstetrics and Gynaecology, Monash University, Melbourne, Victoria, Australia
| | - Angela Kribs
- Department of Neonatology, Children's Hospital University of Cologne, Cologne, Germany
| | - Arjan B Te Pas
- Department of Paediatrics, Leiden University Medical Center, Leiden, Netherlands
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12
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Mian Q, Cheung PY, O'Reilly M, Barton SK, Polglase GR, Schmölzer GM. Impact of delivered tidal volume on the occurrence of intraventricular haemorrhage in preterm infants during positive pressure ventilation in the delivery room. Arch Dis Child Fetal Neonatal Ed 2019; 104:F57-F62. [PMID: 29353261 DOI: 10.1136/archdischild-2017-313864] [Citation(s) in RCA: 45] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/02/2017] [Revised: 12/21/2017] [Accepted: 12/22/2017] [Indexed: 11/04/2022]
Abstract
BACKGROUND AND OBJECTIVES Delivery of inadvertent high tidal volume (VT) during positive pressure ventilation (PPV) in the delivery room is common. High VT delivery during PPV has been associated with haemodynamic brain injury in animal models. We examined if VT delivery during PPV at birth is associated with brain injury in preterm infants <29 weeks' gestation. METHODS A flow-sensor was placed between the mask and the ventilation device. VT values were compared with recently described reference ranges for VT in spontaneously breathing preterm infants at birth. Infants were divided into two groups: VT<6 mL/kg or VT>6 mL/kg (normal and high VT, respectively). Brain injury (eg, intraventricular haemorrhage (IVH)) was assessed using routine ultrasound imaging within the first days after birth. RESULTS A total of 165 preterm infants were included, 124 (75%) had high VT and 41 (25%) normal VT. The mean (SD) gestational age and birth weight in high and normal VT group was similar, 26 (2) and 26 (1) weeks, 858 (251) g and 915 (250) g, respectively. IVH in the high VT group was diagnosed in 63 (51%) infants compared with 5 (13%) infants in the normal VT group (P=0.008).Severe IVH (grade III or IV) developed in 33/124 (27%) infants in the high VT group and 2/41 (6%) in the normal VT group (P=0.01). CONCLUSIONS High VT delivery during mask PPV at birth was associated with brain injury. Strategies to limit VT delivery during mask PPV should be used to prevent high VT delivery.
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Affiliation(s)
- Qaasim Mian
- Centre for the Studies of Asphyxia and Resuscitation, Royal Alexandra Hospital, Edmonton, Alberta, Canada.,Department of Pediatrics, University of Alberta, Edmonton, Alberta, Canada
| | - Po-Yin Cheung
- Centre for the Studies of Asphyxia and Resuscitation, Royal Alexandra Hospital, Edmonton, Alberta, Canada.,Department of Pediatrics, University of Alberta, Edmonton, Alberta, Canada
| | - Megan O'Reilly
- Centre for the Studies of Asphyxia and Resuscitation, Royal Alexandra Hospital, Edmonton, Alberta, Canada.,Department of Pediatrics, University of Alberta, Edmonton, Alberta, Canada
| | - Samantha K Barton
- The Ritchie Centre, Hudson Institute of Medical Research, and Department of Obstetrics and Gynaecology, Monash University, Melbourne, Victoria, Australia
| | - Graeme R Polglase
- The Ritchie Centre, Hudson Institute of Medical Research, and Department of Obstetrics and Gynaecology, Monash University, Melbourne, Victoria, Australia
| | - Georg M Schmölzer
- Centre for the Studies of Asphyxia and Resuscitation, Royal Alexandra Hospital, Edmonton, Alberta, Canada.,Department of Pediatrics, University of Alberta, Edmonton, Alberta, Canada
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13
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Morrison JL, Berry MJ, Botting KJ, Darby JRT, Frasch MG, Gatford KL, Giussani DA, Gray CL, Harding R, Herrera EA, Kemp MW, Lock MC, McMillen IC, Moss TJ, Musk GC, Oliver MH, Regnault TRH, Roberts CT, Soo JY, Tellam RL. Improving pregnancy outcomes in humans through studies in sheep. Am J Physiol Regul Integr Comp Physiol 2018; 315:R1123-R1153. [PMID: 30325659 DOI: 10.1152/ajpregu.00391.2017] [Citation(s) in RCA: 101] [Impact Index Per Article: 16.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Experimental studies that are relevant to human pregnancy rely on the selection of appropriate animal models as an important element in experimental design. Consideration of the strengths and weaknesses of any animal model of human disease is fundamental to effective and meaningful translation of preclinical research. Studies in sheep have made significant contributions to our understanding of the normal and abnormal development of the fetus. As a model of human pregnancy, studies in sheep have enabled scientists and clinicians to answer questions about the etiology and treatment of poor maternal, placental, and fetal health and to provide an evidence base for translation of interventions to the clinic. The aim of this review is to highlight the advances in perinatal human medicine that have been achieved following translation of research using the pregnant sheep and fetus.
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Affiliation(s)
- Janna L Morrison
- Early Origins of Adult Health Research Group, School of Pharmacy and Medical Sciences, University of South Australia, Adelaide, South Australia, Australia
| | - Mary J Berry
- Department of Paediatrics and Child Health, University of Otago , Wellington , New Zealand
| | - Kimberley J Botting
- Department of Physiology, Development, and Neuroscience, University of Cambridge , Cambridge , United Kingdom
| | - Jack R T Darby
- Early Origins of Adult Health Research Group, School of Pharmacy and Medical Sciences, University of South Australia, Adelaide, South Australia, Australia
| | - Martin G Frasch
- Department of Obstetrics and Gynecology, University of Washington , Seattle, Washington
| | - Kathryn L Gatford
- Robinson Research Institute and Adelaide Medical School, University of Adelaide , Adelaide, South Australia , Australia
| | - Dino A Giussani
- Department of Physiology, Development, and Neuroscience, University of Cambridge , Cambridge , United Kingdom
| | - Clint L Gray
- Department of Paediatrics and Child Health, University of Otago , Wellington , New Zealand
| | - Richard Harding
- Department of Anatomy and Developmental Biology, Monash University , Clayton, Victoria , Australia
| | - Emilio A Herrera
- Pathophysiology Program, Biomedical Sciences Institute (ICBM), Faculty of Medicine, University of Chile , Santiago , Chile
| | - Matthew W Kemp
- Division of Obstetrics and Gynecology, University of Western Australia , Perth, Western Australia , Australia
| | - Mitchell C Lock
- Early Origins of Adult Health Research Group, School of Pharmacy and Medical Sciences, University of South Australia, Adelaide, South Australia, Australia
| | - I Caroline McMillen
- Early Origins of Adult Health Research Group, School of Pharmacy and Medical Sciences, University of South Australia, Adelaide, South Australia, Australia
| | - Timothy J Moss
- The Ritchie Centre, Hudson Institute of Medical Research, Department of Obstetrics and Gynaecology, Monash University , Clayton, Victoria , Australia
| | - Gabrielle C Musk
- Animal Care Services, University of Western Australia , Perth, Western Australia , Australia
| | - Mark H Oliver
- Liggins Institute, University of Auckland , Auckland , New Zealand
| | - Timothy R H Regnault
- Department of Obstetrics and Gynecology and Department of Physiology and Pharmacology, Western University, and Children's Health Research Institute , London, Ontario , Canada
| | - Claire T Roberts
- Robinson Research Institute and Adelaide Medical School, University of Adelaide , Adelaide, South Australia , Australia
| | - Jia Yin Soo
- Early Origins of Adult Health Research Group, School of Pharmacy and Medical Sciences, University of South Australia, Adelaide, South Australia, Australia
| | - Ross L Tellam
- Early Origins of Adult Health Research Group, School of Pharmacy and Medical Sciences, University of South Australia, Adelaide, South Australia, Australia
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14
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Malhotra A, Castillo-Melendez M, Allison BJ, Sutherland AE, Nitsos I, Pham Y, Alves de Alencar Rocha AK, Fahey MC, Polglase GR, Jenkin G, Miller SL. Neuropathology as a consequence of neonatal ventilation in premature growth-restricted lambs. Am J Physiol Regul Integr Comp Physiol 2018; 315:R1183-R1194. [PMID: 30230932 DOI: 10.1152/ajpregu.00171.2018] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Fetal growth restriction (FGR) and prematurity are associated with high risk of brain injury and long-term neurological deficits. FGR infants born preterm are commonly exposed to mechanical ventilation, but it is not known whether ventilation differentially induces brain pathology in FGR infants compared with appropriate for gestational age (AGA) infants. We investigated markers of neuropathology in moderate- to late-preterm FGR lambs, compared with AGA lambs, delivered by caesarean birth and ventilated under standard neonatal conditions for 24 h. FGR was induced by single umbilical artery ligation in fetal sheep at 88-day gestation (term, 150 days). At 125-day gestation, FGR and AGA lambs were delivered, dried, intubated, and commenced on noninjurious ventilation, with surfactant administration at 10 min. A group of unventilated FGR and AGA lambs at the same gestation was also examined. Over 24 h, circulating pH, Po2, and lactate levels were similar between groups. Ventilated FGR lambs had lower cerebral blood flow compared with AGA lambs ( P = 0.01). The brain of ventilated FGR lambs showed neuropathology compared with unventilated FGR, and unventilated and ventilated AGA lambs, with increased apoptosis (caspase-3), blood-brain barrier dysfunction (albumin extravasation), activated microglia (Iba-1), and increased expression of cellular oxidative stress (4-hydroxynonenal). The neuropathologies seen in the ventilated FGR brain were most pronounced in the periventricular and subcortical white matter but also evident in the subventricular zone, cortical gray matter, and hippocampus. Ventilation of preterm FGR lambs increased brain injury compared with AGA preterm lambs and unventilated FGR lambs, mediated via increased vascular permeability, neuroinflammation and oxidative stress.
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Affiliation(s)
- Atul Malhotra
- Monash Newborn, Monash Children's Hospital , Melbourne , Australia.,Department of Paediatrics, Monash University , Melbourne , Australia.,The Ritchie Centre, Hudson Institute of Medical Research , Melbourne , Australia
| | - Margie Castillo-Melendez
- The Ritchie Centre, Hudson Institute of Medical Research , Melbourne , Australia.,Department of Obstetrics and Gynaecology, Monash University , Melbourne , Australia
| | - Beth J Allison
- The Ritchie Centre, Hudson Institute of Medical Research , Melbourne , Australia.,Department of Obstetrics and Gynaecology, Monash University , Melbourne , Australia
| | - Amy E Sutherland
- The Ritchie Centre, Hudson Institute of Medical Research , Melbourne , Australia
| | - Ilias Nitsos
- The Ritchie Centre, Hudson Institute of Medical Research , Melbourne , Australia
| | - Yen Pham
- The Ritchie Centre, Hudson Institute of Medical Research , Melbourne , Australia
| | | | - Michael C Fahey
- Department of Paediatrics, Monash University , Melbourne , Australia.,The Ritchie Centre, Hudson Institute of Medical Research , Melbourne , Australia
| | - Graeme R Polglase
- The Ritchie Centre, Hudson Institute of Medical Research , Melbourne , Australia.,Department of Obstetrics and Gynaecology, Monash University , Melbourne , Australia
| | - Graham Jenkin
- The Ritchie Centre, Hudson Institute of Medical Research , Melbourne , Australia.,Department of Obstetrics and Gynaecology, Monash University , Melbourne , Australia
| | - Suzanne L Miller
- The Ritchie Centre, Hudson Institute of Medical Research , Melbourne , Australia.,Department of Obstetrics and Gynaecology, Monash University , Melbourne , Australia
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15
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Galinsky R, Lear CA, Dean JM, Wassink G, Dhillon SK, Fraser M, Davidson JO, Bennet L, Gunn AJ. Complex interactions between hypoxia-ischemia and inflammation in preterm brain injury. Dev Med Child Neurol 2018; 60:126-133. [PMID: 29194585 DOI: 10.1111/dmcn.13629] [Citation(s) in RCA: 78] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 10/17/2017] [Indexed: 12/12/2022]
Abstract
UNLABELLED Children surviving preterm birth have a high risk of disability, particularly cognitive and learning problems. There is extensive clinical and experimental evidence that disability is now primarily related to dysmaturation of white and gray matter, defined by failure of oligodendrocyte maturation and neuronal dendritic arborization, rather than cell death alone. The etiology of this dysmaturation is multifactorial, with contributions from hypoxia-ischemia, infection/inflammation and barotrauma. Intriguingly, these factors can interact to both increase and decrease damage. In this review we summarize preclinical and clinical evidence that all of these factors trigger secondary or chronic inflammation and gliosis. Thus, we hypothesize that these shared pathological features play a key role in a final common pathway that leads to the impaired neural maturation and connectivity and cognitive/motor impairments that are commonly observed in infants born preterm. This raises the possibility that secondary or chronic inflammation may be a viable therapeutic target for delayed interventions to improve neurodevelopmental outcomes after preterm birth. WHAT THIS PAPER ADDS Hypoxia-ischemia, infection/inflammation, and barotrauma/volutrauma all contribute to preterm brain injury. Multiple different triggers of preterm brain injury are associated with central nervous system dysmaturation. Secondary brain inflammation may be a viable target to improve neurodevelopment after preterm birth.
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Affiliation(s)
- Robert Galinsky
- The Department of Physiology, University of Auckland, Auckland, New Zealand.,The Ritchie Centre, Hudson Institute of Medical Research, Clayton, Victoria, Australia
| | - Christopher A Lear
- The Department of Physiology, University of Auckland, Auckland, New Zealand
| | - Justin M Dean
- The Department of Physiology, University of Auckland, Auckland, New Zealand
| | - Guido Wassink
- The Department of Physiology, University of Auckland, Auckland, New Zealand
| | | | - Mhoyra Fraser
- The Department of Physiology, University of Auckland, Auckland, New Zealand
| | - Joanne O Davidson
- The Department of Physiology, University of Auckland, Auckland, New Zealand
| | - Laura Bennet
- The Department of Physiology, University of Auckland, Auckland, New Zealand
| | - Alistair J Gunn
- The Department of Physiology, University of Auckland, Auckland, New Zealand
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16
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Diffusion tensor imaging detects ventilation-induced brain injury in preterm lambs. PLoS One 2017; 12:e0188737. [PMID: 29211751 PMCID: PMC5718608 DOI: 10.1371/journal.pone.0188737] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2017] [Accepted: 11/13/2017] [Indexed: 12/15/2022] Open
Abstract
Purpose Injurious mechanical ventilation causes white matter (WM) injury in preterm infants through inflammatory and haemodynamic pathways. The relative contribution of each of these pathways is not known. We hypothesised that in vivo magnetic resonance imaging (MRI) can detect WM brain injury resulting from mechanical ventilation 24 h after preterm delivery. Further we hypothesised that the combination of inflammatory and haemodynamic pathways, induced by umbilical cord occlusion (UCO) increases brain injury at 24 h. Methods Fetuses at 124±2 days gestation were exposed, instrumented and either ventilated for 15 min using a high tidal-volume (VT) injurious strategy with the umbilical cord intact (INJ; inflammatory pathway only), or occluded (INJ+UCO; inflammatory and haemodynamic pathway). The ventilation groups were compared to lambs that underwent surgery but were not ventilated (Sham), and lambs that did not undergo surgery (unoperated control; Cont). Fetuses were placed back in utero after the 15 min intervention and ewes recovered. Twenty-four hours later, lambs were delivered, placed on a protective ventilation strategy, and underwent MRI of the brain using structural, diffusion tensor imaging (DTI) and magnetic resonance spectroscopy (MRS) techniques. Results Absolute MRS concentrations of creatine and choline were significantly decreased in INJ+UCO compared to Cont lambs (P = 0.03, P = 0.009, respectively); no significant differences were detected between the INJ or Sham groups and the Cont group. Axial diffusivities in the internal capsule and frontal WM were lower in INJ and INJ+UCO compared to Cont lambs (P = 0.05, P = 0.04, respectively). Lambs in the INJ and INJ+UCO groups had lower mean diffusivities in the frontal WM compared to Cont group (P = 0.04). DTI colour mapping revealed lower diffusivity in specific WM regions in the Sham, INJ, and INJ+UCO groups compared to the Cont group, but the differences did not reach significance. INJ+UCO lambs more likely to exhibit lower WM diffusivity than INJ lambs. Conclusions Twenty-four hours after injurious ventilation, DTI and MRS showed increased brain injury in the injuriously ventilated lambs compared to controls. DTI colour mapping threshold approach provides evidence that the haemodynamic and inflammatory pathways have additive effects on the progression of brain injury compared to the inflammatory pathway alone.
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17
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The Effect of Mechanical Ventilation on TASK-1 Expression in the Brain in a Rat Model. Can Respir J 2017; 2017:8530352. [PMID: 29093631 PMCID: PMC5637865 DOI: 10.1155/2017/8530352] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2017] [Revised: 08/05/2017] [Accepted: 08/13/2017] [Indexed: 12/30/2022] Open
Abstract
Background and Objective TWIK-related acid-sensitive potassium channel 1 (TASK-1) is closely related to respiratory central control and neuronal injury. We investigated the effect of MV on TASK-1's functions and explored the mechanism using a rat model. Methods Male Sprague-Dawley rats were randomized to three groups: (1) high tidal volume (HVt): MV for four hours with Vt at 10 mL/kg; (2) low Vt (LVt): MV for four hours with Vt at 5 mL/kg; (3) basal (BAS): anesthetized and unventilated animals. We measured lung histology and plasma and brain levels of proteins (IL-6, TNF-α, and S-100B) and determined TASK-1 levels in rat brainstems as a marker of respiratory centre activity. Results The LISs (lung injury scores) were significantly higher in the HVt group. Brain inflammatory cytokines levels were different to those in serum. TASK-1 levels were significantly lower in the MV groups (P = 0.002) and the HVt group tended to have a lower level of TASK-1 than the LVt group. Conclusion MV causes not only lung injury, but also brain injury. MV affects the regulation of the respiratory centre, perhaps causing damage to it. Inflammation is probably not the main mechanism of ventilator-related brain injury.
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18
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Antenatal exposure to antidepressants is associated with altered brain development in very preterm-born neonates. Neuroscience 2017; 342:252-262. [DOI: 10.1016/j.neuroscience.2016.11.025] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2015] [Revised: 11/15/2016] [Accepted: 11/17/2016] [Indexed: 11/21/2022]
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19
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Alahmari DM, Skiöld B, Barton SK, Nitsos I, McDonald C, Miller SL, Zahra V, Galinsky R, Wu Q, Farrell MJ, Moss TJ, Hooper SB, Pearson JT, Polglase GR. Diffusion Tensor Imaging Colour Mapping Threshold for Identification of Ventilation-Induced Brain Injury after Intrauterine Inflammation in Preterm Lambs. Front Pediatr 2017; 5:70. [PMID: 28424764 PMCID: PMC5380678 DOI: 10.3389/fped.2017.00070] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/28/2016] [Accepted: 03/20/2017] [Indexed: 11/23/2022] Open
Abstract
PURPOSE The aim of this study is to examine whether advanced magnetic resonance imaging (MRI) techniques can detect early brain injury caused by intrauterine inflammation and inappropriate initial respiratory support in preterm lambs. HYPOTHESIS Neuropathology caused by intrauterine inflammation is exacerbated by mechanical ventilation at birth and is detectable with advanced MRI techniques. METHODS Pregnant ewes received intra-amniotic lipopolysaccharide (LPS) 7 days prior to delivery at ~125 days of gestation (85% of gestation), whereupon lambs were delivered and randomised to receive an injurious (LPS + INJ, n = 6) or protective (LPS + PROT, n = 6) ventilation strategy. MRI of the brain was conducted 90 min after preterm delivery, using structural, diffusion tensor imaging (DTI), and magnetic resonance spectroscopy (MRS) techniques. A colour map threshold technique was utilised to compare distributions of low diffusivity voxels in the brains of LPS-exposed lambs with those not exposed to LPS (PROT, n = 7 PROT and INJ, n = 10). RESULTS No overt cerebral injury was identified on structural MRI images of any lamb. However, on DTI, axial diffusivity, radial diffusivity, and mean diffusivity values were lower and significantly more heterogeneous in specific brain regions of lambs in the LPS + INJ group compared to the LPS + PROT group. Colour mapping revealed lower diffusivity in the thalamus, periventricular white matter, internal capsule, and frontal white matter in the LPS + INJ group compared to LPS + PROT group. The MRS peak area ratios of lactate, relative to those for the metabolites creatine, choline, and N-acetylaspartate, were not different between LPS-exposed groups. Lambs exposed to LPS had lower diffusivity within the white matter regions assessed than non-LPS-treated control lambs. CONCLUSION DTI colour map threshold techniques detected early brain injury in preterm lambs exposed to intrauterine inflammation and detected differences between injurious and protective ventilation strategies. DTI mapping approaches are potentially useful for early detection of subtle brain injury in premature infants.
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Affiliation(s)
- Dhafer M Alahmari
- Department of Medical Imaging and Radiation Sciences, Monash Biomedicine Discovery Institute, Monash University, Clayton, VIC, Australia.,Monash Biomedical Imaging, Monash University, Clayton, VIC, Australia
| | - Beatrice Skiöld
- Department of Women's and Children's Health, Karolinska Institutet, Stockholm, Sweden
| | - Samantha K Barton
- The Ritchie Centre, Hudson Institute of Medical Research, Clayton, VIC, Australia
| | - Ilias Nitsos
- The Ritchie Centre, Hudson Institute of Medical Research, Clayton, VIC, Australia
| | - Courtney McDonald
- The Ritchie Centre, Hudson Institute of Medical Research, Clayton, VIC, Australia
| | - Suzanne L Miller
- The Ritchie Centre, Hudson Institute of Medical Research, Clayton, VIC, Australia.,Department of Obstetrics and Gynaecology and Paediatrics, Monash University, Clayton, VIC, Australia
| | - Valerie Zahra
- The Ritchie Centre, Hudson Institute of Medical Research, Clayton, VIC, Australia
| | - Robert Galinsky
- The Ritchie Centre, Hudson Institute of Medical Research, Clayton, VIC, Australia.,Department of Physiology, University of Auckland, Grafton, New Zealand
| | - Qizhu Wu
- Monash Biomedical Imaging, Monash University, Clayton, VIC, Australia
| | - Michael John Farrell
- Department of Medical Imaging and Radiation Sciences, Monash Biomedicine Discovery Institute, Monash University, Clayton, VIC, Australia.,Monash Biomedical Imaging, Monash University, Clayton, VIC, Australia
| | - Timothy J Moss
- The Ritchie Centre, Hudson Institute of Medical Research, Clayton, VIC, Australia.,Department of Obstetrics and Gynaecology and Paediatrics, Monash University, Clayton, VIC, Australia
| | - Stuart B Hooper
- The Ritchie Centre, Hudson Institute of Medical Research, Clayton, VIC, Australia.,Department of Obstetrics and Gynaecology and Paediatrics, Monash University, Clayton, VIC, Australia
| | - James T Pearson
- Monash Biomedical Imaging, Monash University, Clayton, VIC, Australia.,Department of Physiology, Monash University, Clayton, VIC, Australia.,Department of Cardiac Physiology, National Cerebral and Cardiovascular Center, Suita, Osaka, Japan
| | - Graeme R Polglase
- The Ritchie Centre, Hudson Institute of Medical Research, Clayton, VIC, Australia.,Department of Obstetrics and Gynaecology and Paediatrics, Monash University, Clayton, VIC, Australia
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20
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Barton SK, Tolcos M, Miller SL, Christoph-Roehr C, Schmölzer GM, Moss TJM, Hooper SB, Wallace EM, Polglase GR. Ventilation-Induced Brain Injury in Preterm Neonates: A Review of Potential Therapies. Neonatology 2016; 110:155-62. [PMID: 27105430 DOI: 10.1159/000444918] [Citation(s) in RCA: 42] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/16/2015] [Accepted: 02/23/2016] [Indexed: 11/19/2022]
Abstract
Mechanical ventilation is a risk factor for cerebral inflammation and brain injury in preterm neonates. The risk increases proportionally with the intensity of treatment. Recent studies have shown that cerebral inflammation and injury can be initiated in the delivery room. At present, initiation of intermittent positive pressure ventilation (IPPV) in the delivery room is one of the least controlled interventions a preterm infant will likely face. Varying pressures and volumes administered shortly after birth are sufficient to trigger pathways of ventilation-induced lung and brain injury. The pathways involved in ventilation-induced brain injury include a complex inflammatory cascade and haemodynamic instability, both of which have an impact on the brain. However, regardless of the strategy employed to deliver IPPV, any ventilation has the potential to have an impact on the immature brain. This is particularly important given that preterm infants are already at a high risk for brain injury simply due to immaturity. This highlights the importance of improving the initial respiratory support in the delivery room. We review the mechanisms of ventilation-induced brain injury and discuss the need for, and the most likely, current therapeutic agents to protect the preterm brain. These include therapies already employed clinically, such as maternal glucocorticoid therapy and allopurinol, as well as other agents, such as erythropoietin, human amnion epithelial cells and melatonin, already showing promise in preclinical studies. Their mechanisms of action are discussed, highlighting their potential for use immediately after birth.
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Affiliation(s)
- Samantha K Barton
- The Ritchie Centre, Hudson Institute of Medical Research, Clayton, Vic., UK
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21
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Barton SK, McDougall ARA, Melville JM, Moss TJM, Zahra VA, Lim T, Crossley KJ, Polglase GR, Tolcos M. Differential short-term regional effects of early high dose erythropoietin on white matter in preterm lambs after mechanical ventilation. J Physiol 2015; 594:1437-49. [PMID: 26332509 DOI: 10.1113/jp271376] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2015] [Accepted: 08/13/2015] [Indexed: 11/08/2022] Open
Abstract
Inadvertently injurious ventilation of preterm neonates in the delivery room can cause cerebral white matter (WM) inflammation and injury. We investigated the impact of an early high dose of recombinant human erythropoietin (EPO) on ventilation-induced WM changes in preterm lambs. Injurious ventilation, targeting a V(T) of 15 ml kg(-1) with no positive end-expiratory pressure, was initiated for 15 min in preterm lambs (0.85 gestation). Conventional ventilation was continued for a further 105 min. Lambs received either 5000 IU kg(-1) of EPO (EPREX®; Vent+EPO; n = 6) or vehicle (Vent; n = 8) via an umbilical vein at 4 ± 2 min. Markers of WM injury and inflammation were assessed using quantitative real-time PCR (qPCR) and immunohistochemistry and compared to a group of unventilated controls (UVC; n = 4). In Vent+EPO lambs compared to Vent lambs: (i) interleukin (IL)-1β and IL-6 mRNA levels in the periventricular WM and IL-8 mRNA levels in the subcortical WM were higher (P < 0.05 for all); (ii) the density of microglia within the aggregations was not different in the periventricular WM and was lower in the subcortical WM (P = 0.001); (iii) the density of astrocytes was lower in the subcortical WM (P = 0.002); (iv) occludin and claudin-1 mRNA levels were higher in the periventricular WM (P < 0.02 for all) and (vi) the number of blood vessels with protein extravasation was lower (P < 0.05). Recombinant human EPO had variable regional effects within the WM when administered during injurious ventilation. The adverse short-term outcomes discourage the use of early high dose EPO administration in preterm ventilated babies.
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Affiliation(s)
- Samantha K Barton
- The Ritchie Centre, Hudson Institute of Medical Research, Clayton, Victoria, 3168, Australia
| | - Annie R A McDougall
- The Ritchie Centre, Hudson Institute of Medical Research, Clayton, Victoria, 3168, Australia.,Department of Biochemistry and Molecular Biology, Monash University, Clayton, Victoria, 3168, Australia
| | - Jacqueline M Melville
- The Ritchie Centre, Hudson Institute of Medical Research, Clayton, Victoria, 3168, Australia
| | - Timothy J M Moss
- The Ritchie Centre, Hudson Institute of Medical Research, Clayton, Victoria, 3168, Australia.,Department of Obstetrics and Gynaecology, Monash University, Clayton, Victoria, 3168, Australia
| | - Valerie A Zahra
- The Ritchie Centre, Hudson Institute of Medical Research, Clayton, Victoria, 3168, Australia
| | - Tammy Lim
- The Ritchie Centre, Hudson Institute of Medical Research, Clayton, Victoria, 3168, Australia
| | - Kelly J Crossley
- The Ritchie Centre, Hudson Institute of Medical Research, Clayton, Victoria, 3168, Australia
| | - Graeme R Polglase
- The Ritchie Centre, Hudson Institute of Medical Research, Clayton, Victoria, 3168, Australia.,Department of Obstetrics and Gynaecology, Monash University, Clayton, Victoria, 3168, Australia
| | - Mary Tolcos
- The Ritchie Centre, Hudson Institute of Medical Research, Clayton, Victoria, 3168, Australia.,Department of Obstetrics and Gynaecology, Monash University, Clayton, Victoria, 3168, Australia
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22
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Schwaberger B, Pichler G, Avian A, Binder-Heschl C, Baik N, Urlesberger B. Do Sustained Lung Inflations during Neonatal Resuscitation Affect Cerebral Blood Volume in Preterm Infants? A Randomized Controlled Pilot Study. PLoS One 2015; 10:e0138964. [PMID: 26406467 PMCID: PMC4583511 DOI: 10.1371/journal.pone.0138964] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2015] [Accepted: 09/04/2015] [Indexed: 11/18/2022] Open
Abstract
BACKGROUND Sustained lung inflations (SLI) during neonatal resuscitation may promote alveolar recruitment in preterm infants. While most of the studies focus on respiratory outcome, the impact of SLI on the brain hasn't been investigated yet. OBJECTIVE Do SLI affect cerebral blood volume (CBV) in preterm infants? METHODS Preterm infants of gestation 28 weeks 0 days to 33 weeks 6 days with requirement for respiratory support (RS) were included in this randomized controlled pilot trial. Within the first 15 minutes after birth near-infrared spectroscopy (NIRS) measurements using 'NIRO-200-NX' (Hamamatsu, Japan) were performed to evaluate changes in CBV and cerebral tissue oxygenation. Two groups were compared based on RS: In SLI group RS was given by applying 1-3 SLI (30 cmH2O for 15 s) continued by respiratory standard care. Control group received respiratory standard care only. RESULTS 40 infants (20 in each group) with mean gestational age of 32 weeks one day (±2 days) and birth weight of 1707 (±470) g were included. In the control group ΔCBV was significantly decreasing, whereas in SLI group ΔCBV showed similar values during the whole period of 15 minutes. Comparing both groups within the first 15 minutes ΔCBV showed a tendency toward different overall courses (p = 0.051). CONCLUSION This is the first study demonstrating an impact of SLI on CBV. Further studies are warranted including reconfirmation of the present findings in infants with lower gestational age. Future investigations on SLI should not only focus on respiratory outcome but also on the consequences on the developing brain. TRIAL REGISTRATION German Clinical Trials Register DRKS00005161 https://drks-neu.uniklinik-freiburg.de/drks_web/setLocale_EN.do.
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Affiliation(s)
- Bernhard Schwaberger
- Research Unit for Cerebral Development and Oximetry, Medical University of Graz, Graz, Austria
- Research Unit for Neonatal Micro- and Macrocirculation, Medical University of Graz, Graz, Austria
- Division of Neonatology, Department of Pediatrics, Medical University of Graz, Graz, Austria
| | - Gerhard Pichler
- Research Unit for Cerebral Development and Oximetry, Medical University of Graz, Graz, Austria
- Research Unit for Neonatal Micro- and Macrocirculation, Medical University of Graz, Graz, Austria
- Division of Neonatology, Department of Pediatrics, Medical University of Graz, Graz, Austria
| | - Alexander Avian
- Institute for Medical Informatics, Statistics and Documentation, Medical University of Graz, Graz, Austria
| | - Corinna Binder-Heschl
- Research Unit for Cerebral Development and Oximetry, Medical University of Graz, Graz, Austria
- Research Unit for Neonatal Micro- and Macrocirculation, Medical University of Graz, Graz, Austria
- Division of Neonatology, Department of Pediatrics, Medical University of Graz, Graz, Austria
| | - Nariae Baik
- Research Unit for Cerebral Development and Oximetry, Medical University of Graz, Graz, Austria
- Research Unit for Neonatal Micro- and Macrocirculation, Medical University of Graz, Graz, Austria
- Division of Neonatology, Department of Pediatrics, Medical University of Graz, Graz, Austria
| | - Berndt Urlesberger
- Research Unit for Cerebral Development and Oximetry, Medical University of Graz, Graz, Austria
- Research Unit for Neonatal Micro- and Macrocirculation, Medical University of Graz, Graz, Austria
- Division of Neonatology, Department of Pediatrics, Medical University of Graz, Graz, Austria
- * E-mail:
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23
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Barton SK, Melville JM, Tolcos M, Polglase GR, McDougall ARA, Azhan A, Crossley KJ, Jenkin G, Moss TJM. Human Amnion Epithelial Cells Modulate Ventilation-Induced White Matter Pathology in Preterm Lambs. Dev Neurosci 2015; 37:338-48. [PMID: 25720586 DOI: 10.1159/000371415] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2014] [Accepted: 12/08/2014] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND Preterm infants can be inadvertently exposed to high tidal volumes (VT) during resuscitation in the delivery room due to limitations of available equipment. High VT ventilation of preterm lambs produces cerebral white matter (WM) pathology similar to that observed in preterm infants who develop cerebral palsy. We hypothesized that human amnion epithelial cells (hAECs), which have anti-inflammatory and regenerative properties, would reduce ventilation-induced WM pathology in neonatal late preterm lamb brains. METHODS Two groups of lambs (0.85 gestation) were used, as follows: (1) ventilated lambs (Vent; n = 8) were ventilated using a protocol that induces injury (VT targeting 15 ml/kg for 15 min, with no positive end-expiratory pressure) and were then maintained for another 105 min, and (2) ventilated + hAECs lambs (Vent+hAECs; n = 7) were similarly ventilated but received intravenous and intratracheal administration of 9 × 10(7) hAECs (18 × 10(7) hAECs total) at birth. Oxygenation and ventilation parameters were monitored in real time; cerebral oxygenation was measured using near-infrared spectroscopy. qPCR (quantitative real-time PCR) and immunohistochemistry were used to assess inflammation, vascular leakage and astrogliosis in both the periventricular and subcortical WM of the frontal and parietal lobes. An unventilated control group (UVC; n = 5) was also used for qPCR analysis of gene expression. Two-way repeated measures ANOVA was used to compare physiological data. Student's t test and one-way ANOVA were used for immunohistological and qPCR data comparisons, respectively. RESULTS Respiratory parameters were not different between groups. Interleukin (IL)-6 mRNA levels in subcortical WM were lower in the Vent+hAECs group than the Vent group (p = 0.028). IL-1β and IL-6 mRNA levels in periventricular WM were higher in the Vent+hAECs group than the Vent group (p = 0.007 and p = 0.001, respectively). The density of Iba-1-positive microglia was lower in the subcortical WM of the parietal lobes (p = 0.010) in the Vent+hAECs group but not in the periventricular WM. The number of vessels in the WM of the parietal lobe exhibiting protein extravasation was lower (p = 0.046) in the Vent+hAECs group. Claudin-1 mRNA levels were higher in the periventricular WM (p = 0.005). The density of GFAP-positive astrocytes was not different between groups. CONCLUSIONS Administration of hAECs at the time of birth alters the effects of injurious ventilation on the preterm neonatal brain. Further studies are required to understand the regional differences in the effects of hAECs on ventilation-induced WM pathology and their net effect on the developing brain.
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Affiliation(s)
- Samantha K Barton
- The Ritchie Centre, MIMR-PHI Institute of Medical Research, Clayton, Vic., Australia
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24
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Barton SK, Tolcos M, Miller SL, Roehr CC, Schmölzer GM, Davis PG, Moss TJM, LaRosa DA, Hooper SB, Polglase GR. Unraveling the Links Between the Initiation of Ventilation and Brain Injury in Preterm Infants. Front Pediatr 2015; 3:97. [PMID: 26618148 PMCID: PMC4639621 DOI: 10.3389/fped.2015.00097] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/14/2015] [Accepted: 10/26/2015] [Indexed: 11/13/2022] Open
Abstract
The initiation of ventilation in the delivery room is one of the most important but least controlled interventions a preterm infant will face. Tidal volumes (V T) used in the neonatal intensive care unit are carefully measured and adjusted. However, the V Ts that an infant receives during resuscitation are usually unmonitored and highly variable. Inappropriate V Ts delivered to preterm infants during respiratory support substantially increase the risk of injury and inflammation to the lungs and brain. These may cause cerebral blood flow instability and initiate a cerebral inflammatory cascade. The two pathways increase the risk of brain injury and potential life-long adverse neurodevelopmental outcomes. The employment of new technologies, including respiratory function monitors, can improve and guide the optimal delivery of V Ts and reduce confounders, such as leak. Better respiratory support in the delivery room has the potential to improve both respiratory and neurological outcomes in this vulnerable population.
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Affiliation(s)
- Samantha K Barton
- The Ritchie Centre, Hudson Institute of Medical Research , Melbourne, VIC , Australia
| | - Mary Tolcos
- The Ritchie Centre, Hudson Institute of Medical Research , Melbourne, VIC , Australia ; Department of Obstetrics and Gynecology, Monash University , Melbourne, VIC , Australia
| | - Suzie L Miller
- The Ritchie Centre, Hudson Institute of Medical Research , Melbourne, VIC , Australia ; Department of Obstetrics and Gynecology, Monash University , Melbourne, VIC , Australia
| | - Charles C Roehr
- The Ritchie Centre, Hudson Institute of Medical Research , Melbourne, VIC , Australia ; Newborn Services, John Radcliffe Hospital, Oxford University Hospitals , Oxford , UK
| | - Georg M Schmölzer
- Department of Pediatrics, University of Alberta , Edmonton, AB , Canada ; Centre for the Study of Asphyxia and Resuscitation, Neonatal Research Unit, Royal Alexandra Hospital, Alberta Health Services , Edmonton, AB , Canada
| | - Peter G Davis
- Neonatal Services, Newborn Research Centre, The Royal Women's Hospital , Melbourne, VIC , Australia
| | - Timothy J M Moss
- The Ritchie Centre, Hudson Institute of Medical Research , Melbourne, VIC , Australia ; Department of Obstetrics and Gynecology, Monash University , Melbourne, VIC , Australia
| | - Domenic A LaRosa
- The Ritchie Centre, Hudson Institute of Medical Research , Melbourne, VIC , Australia
| | - Stuart B Hooper
- The Ritchie Centre, Hudson Institute of Medical Research , Melbourne, VIC , Australia ; Department of Obstetrics and Gynecology, Monash University , Melbourne, VIC , Australia
| | - Graeme R Polglase
- The Ritchie Centre, Hudson Institute of Medical Research , Melbourne, VIC , Australia ; Department of Obstetrics and Gynecology, Monash University , Melbourne, VIC , Australia
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