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Rabaglino MB, Bojsen-Møller Secher J, Sirard MA, Hyttel P, Kadarmideen HN. Epigenomic and transcriptomic analyses reveal early activation of the HPG axis in in vitro-produced male dairy calves. FASEB J 2021; 35:e21882. [PMID: 34460963 DOI: 10.1096/fj.202101067r] [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: 06/24/2021] [Revised: 08/03/2021] [Accepted: 08/12/2021] [Indexed: 12/13/2022]
Abstract
In cattle, several calves born after IVP ("in vitro" embryo production) present similar birthweight to those generated after MOET (multiple ovulation and embryo transfer). However, the underlying molecular patterns in organs involved in the developmental process are unknown and could indicate physiological programming. The objectives of this study were: (1) to compare epigenomic and transcriptomic modifications in the hypothalamus, pituitary, gonadal and adrenal organs between 3 months old ovum pick-up-IVP and MOET male calves (n = 4 per group) and (2) to use blood epigenomic data to proxy methylation of the inner organs. Extracted gDNA and RNA were sequenced through whole-genome bisulfite sequencing and RNA sequencing, respectively. Next, bioinformatic analyses determined differentially methylated cytosines (DMC) and differentially expressed genes (DEG) (FDR < 0.05) in IVP versus MOET samples and the KEGG pathways that were overrepresented by genes associated with DMC or DEG (FDR < 0.1). Pathways related to hypothalamus, pituitary, gonadal (HPG) axis activation (GnRH secretion in the hypothalamus, GnRH signaling in the pituitary, and steroidogenesis in the testicle) were enriched in IVP calves. Modeling the effect of the methylation levels and the group on the expression of all the genes involved in these pathways confirmed their upregulation in HPG organs in IVP calves. The application of the DIABLO method allowed the identification of 15 epigenetic and five transcriptomic biomarkers, which were able to predict the embryo origin using the epigenomic data from the blood. In conclusion, the use of an integrated epigenomic-transcriptomic approach suggested an early activation of the HPG axis in male IVP calves compared to MOET counterparts, and the identification of potential biomarkers allowed the use of blood samples to proxy methylation levels of the relevant internal organs.
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Affiliation(s)
- María B Rabaglino
- Quantitative Genetics, Bioinformatics and Computational Biology Group, Department of Applied Mathematics and Computer Science, Technical University of Denmark, Lyngby, Denmark
| | | | - Marc-André Sirard
- Departement des Sciences Animales, Centre de Recherche en Reproduction, Développement et Santé Inter-générationnelle (CRDSI), Université Laval, Laval, Quebec, Canada
| | - Poul Hyttel
- Department of Veterinary Clinical Sciences, University of Copenhagen, Frederiksberg, Denmark
| | - Haja N Kadarmideen
- Quantitative Genetics, Bioinformatics and Computational Biology Group, Department of Applied Mathematics and Computer Science, Technical University of Denmark, Lyngby, Denmark
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Lock MC, Tellam RL, Darby JRT, Soo JY, Brooks DA, Macgowan CK, Selvanayagam JB, Porrello ER, Seed M, Keller-Wood M, Morrison JL. Differential gene responses 3 days following infarction in the fetal and adolescent sheep heart. Physiol Genomics 2020; 52:143-159. [PMID: 31961761 DOI: 10.1152/physiolgenomics.00092.2019] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
There are critical molecular mechanisms that can be activated to induce myocardial repair, and in humans this is most efficient during fetal development. The timing of heart development in relation to birth and the size/electrophysiology of the heart are similar in humans and sheep, providing a model to investigate the repair capacity of the mammalian heart and how this can be applied to adult heart repair. Myocardial infarction was induced by ligation of the left anterior descending coronary artery in fetal (105 days gestation when cardiomyocytes are proliferative) and adolescent sheep (6 mo of age when all cardiomyocytes have switched to an adult phenotype). An ovine gene microarray was used to compare gene expression in sham and infarcted (remote, border and infarct areas) cardiac tissue from fetal and adolescent hearts. The gene response to myocardial infarction was less pronounced in fetal compared with adolescent sheep hearts and there were unique gene responses at each age. There were also region-specific changes in gene expression between each age, in the infarct tissue, tissue bordering the infarct, and tissue remote from the infarction. In total, there were 880 genes that responded to MI uniquely in the adolescent samples compared with 170 genes in the fetal response, as well as 742 overlap genes that showed concordant direction of change responses to infarction at both ages. In response to myocardial infarction, there were specific changes in genes within pathways of mitochondrial oxidation, muscle contraction, and hematopoietic cell lineages, suggesting that the control of energy utilization and immune function are critical for effective heart repair. The more restricted gene response in the fetus may be an important factor in its enhanced capacity for cardiac repair.
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Affiliation(s)
- Mitchell C Lock
- 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
| | - 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
| | - Jia Yin Soo
- Early Origins of Adult Health Research Group, School of Pharmacy and Medical Sciences, University of South Australia, Adelaide, South Australia, Australia
| | - Doug A Brooks
- Mechanisms in Cell Biology and Disease Research Group, School of Pharmacy and Medical Sciences, University of South Australia, Adelaide, South Australia, Australia
| | | | - Joseph B Selvanayagam
- Cardiac Imaging Research Group, Department of Heart Health, South Australian Health & Medical Research Institute, and Flinders University, Adelaide, South Australia, Australia
| | - Enzo R Porrello
- Murdoch Children's Research Institute, The Royal Children's Hospital, Parkville, Victoria, Australia.,Department of Physiology, The University of Melbourne, Parkville, Victoria, Australia
| | - Mike Seed
- Hospital for Sick Children, Division of Cardiology, Toronto, Ontario, Canada
| | | | - Janna L Morrison
- 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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Yu K, Rodriguez MD, Paul Z, Gordon E, Rice K, Triplett EW, Keller-Wood M, Wood CE. Proof of principle: Physiological transfer of small numbers of bacteria from mother to fetus in late-gestation pregnant sheep. PLoS One 2019; 14:e0217211. [PMID: 31170184 PMCID: PMC6553719 DOI: 10.1371/journal.pone.0217211] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2018] [Accepted: 05/07/2019] [Indexed: 01/08/2023] Open
Abstract
Fetal development is thought to proceed in a sterile environment. Recent reports of the presence of bacterial DNA in human placenta, the transfer of live bacteria from mother to fetus after hypoxia in the pregnant sheep, and the presence of bacteria in the meconium of newborn infants have suggested that the fetus might be exposed to bacteria in utero. The present experiments were designed to test the hypothesis that small numbers of bacteria introduced into the maternal bloodstream (too few to induce fever or changes in maternal food consumption), can be found in the fetus days later. We injected 100 colony forming units of green-, red- and far red- fluorescent protein (GFP, RFP, FRFP) expressing S. aureus into late-gestation pregnant sheep intravenously. Five to 7 days later, the animals were euthanized and tissues collected for analysis of GFP. The inoculations did not cause any fever or other measurable behavioral response in the ewes, but did result in the appearance of GFP DNA, and protein in various tissues within the fetuses. Immunohistochemical analysis reveals GFP protein-containing bacteria that appear to be mostly contained within other cells. We were unable to recover any live GFP-expressing bacteria from the fetal tissues. We conclude that S. aureus, and perhaps other bacteria, gain access to the fetus, although it is not clear from these experiments that they survive in the fetus. It is possible that these low inocula and their progeny were effectively cleared by the fetal immune system.
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Affiliation(s)
- Kevin Yu
- Department of Physiology and Functional Genomics, University of Florida College of Medicine, Gainesville, Florida, United States of America
| | - Michelle D. Rodriguez
- Department of Microbiology and Cell Science, University of Florida Institute of Food and Agricultural Sciences, Gainesville, Florida, United States of America
| | - Zubin Paul
- Department of Physiology and Functional Genomics, University of Florida College of Medicine, Gainesville, Florida, United States of America
| | - Elizabeth Gordon
- Department of Physiology and Functional Genomics, University of Florida College of Medicine, Gainesville, Florida, United States of America
| | - Kelly Rice
- Department of Microbiology and Cell Science, University of Florida Institute of Food and Agricultural Sciences, Gainesville, Florida, United States of America
| | - Eric W. Triplett
- Department of Microbiology and Cell Science, University of Florida Institute of Food and Agricultural Sciences, Gainesville, Florida, United States of America
| | - Maureen Keller-Wood
- Department of Pharmacodynamics, University of Florida College of Pharmacy, Gainesville, Florida, United States of America
| | - Charles E. Wood
- Department of Physiology and Functional Genomics, University of Florida College of Medicine, Gainesville, Florida, United States of America
- * E-mail:
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Wood CE, Keller-Wood M. Current paradigms and new perspectives on fetal hypoxia: implications for fetal brain development in late gestation. Am J Physiol Regul Integr Comp Physiol 2019; 317:R1-R13. [PMID: 31017808 DOI: 10.1152/ajpregu.00008.2019] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
The availability of oxygen to the fetus is limited by the route taken by oxygen from the atmosphere to fetal tissues, aided or diminished by pregnancy-associated changes in maternal physiology and, ultimately, a function of atmospheric pressure and composition of the mother's inspired gas. Much of our understanding of the fetal physiological response to hypoxia comes from experiments designed to elucidate the cardiovascular and endocrine responses to transient hypoxia. Complementing this work is equally impactful research into the origins of intrauterine growth restriction in which animal models designed to restrict the transfer of oxygen from the maternal to the fetal circulation were used. A common assumption has been that outcomes measured after a period of hypoxia are related to cellular deprivation of oxygen and reoxygenation: an assumption based on a focus on what we can see "under the streetlights." Recent studies demonstrate that availability of oxygen may not tell the whole story. Transient hypoxia in the fetal sheep stimulates transcriptomics responses that mirror inflammation. This response is accompanied by the appearance of bacteria in the fetal brain and other tissues, likely resulting from a hypoxia-stimulated release of bacteria from the placenta. The appearance of bacteria in the fetus after transient hypoxia complements the recent discovery of bacterial DNA in the normal human placenta and in the tissues of fetal sheep. An understanding of the mechanism of the physiological, cellular, and molecular responses to hypoxia requires an appreciation of stimuli other than cellular oxygen deprivation: stimuli that we would have never known about without looking "between the streetlights," illuminating direct responses to the manipulated variables.
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Affiliation(s)
- Charles E Wood
- Department of Physiology and Functional Genomics, University of Florida College of Medicine , Gainesville, Florida
| | - Maureen Keller-Wood
- Department of Pharmacodynamics, University of Florida College of Pharmacy , Gainesville, Florida
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Chang EI, Zarate MA, Arndt TJ, Richards EM, Rabaglino MB, Keller-Wood M, Wood CE. Ketamine Reduces Inflammation Pathways in the Hypothalamus and Hippocampus Following Transient Hypoxia in the Late-Gestation Fetal Sheep. Front Physiol 2019; 9:1858. [PMID: 30666211 PMCID: PMC6330334 DOI: 10.3389/fphys.2018.01858] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2018] [Accepted: 12/11/2018] [Indexed: 12/12/2022] Open
Abstract
The physiological response to hypoxia in the fetus has been extensively studied with regard to redistribution of fetal combined ventricular output and sparing of oxygen delivery to fetal brain and heart. Previously, we have shown that the fetal brain is capable of mounting changes in gene expression that are consistent with tissue inflammation. The present study was designed to use transcriptomics and systems biology modeling to test the hypothesis that ketamine reduces or prevents the upregulation of inflammation-related pathways in hypothalamus and hippocampus after transient hypoxic hypoxia. Chronically catheterized fetal sheep (122 ± 5 days gestation) were subjected to 30 min hypoxia (relative reduction in PaO2∼50%) caused by infusion of nitrogen into the inspired gas of the pregnant ewe. RNA was isolated from fetal hypothalamus and hippocampus collected 24 h after hypoxia, and was analyzed for gene expression using the Agilent 15.5 k ovine microarray. Ketamine, injected 10 min prior to hypoxia, reduced the cerebral immune response activation to the hypoxia in both brain regions. Genes both upregulated by hypoxia and downregulated by ketamine after hypoxia were significantly associated with gene ontology terms and KEGG pathways that are, themselves, associated with the tissue response to exposure to bacteria. We conclude that the results are consistent with interruption of the cellular response to bacteria by ketamine.
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Affiliation(s)
- Eileen I Chang
- Department of Physiology and Functional Genomics, University of Florida College of Medicine, Gainesville, FL, United States
| | - Miguel A Zarate
- Department of Physiology and Functional Genomics, University of Florida College of Medicine, Gainesville, FL, United States
| | - Thomas J Arndt
- Department of Physiology and Functional Genomics, University of Florida College of Medicine, Gainesville, FL, United States
| | - Elaine M Richards
- Department of Pharmacodynamics, University of Florida College of Pharmacy, Gainesville, FL, United States
| | - Maria B Rabaglino
- CEPROCOR, National Scientific and Technical Research Council (CONICET), Córdoba, Argentina
| | - Maureen Keller-Wood
- Department of Pharmacodynamics, University of Florida College of Pharmacy, Gainesville, FL, United States
| | - Charles E Wood
- Department of Physiology and Functional Genomics, University of Florida College of Medicine, Gainesville, FL, United States
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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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Rabaglino MB, Keller‐Wood M, Wood CE. A transcriptomics model of estrogen action in the ovine fetal hypothalamus: evidence for estrogenic effects of ICI 182,780. Physiol Rep 2018; 6:e13871. [PMID: 30221477 PMCID: PMC6139289 DOI: 10.14814/phy2.13871] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2018] [Accepted: 08/28/2018] [Indexed: 01/13/2023] Open
Abstract
Estradiol plays a critical role in stimulating the fetal hypothalamus-pituitary-adrenal axis at the end of gestation. Estradiol action is mediated through nuclear and membrane receptors that can be modulated by ICI 182,780, a pure antiestrogen compound. The objective of this study was to evaluate the transcriptomic profile of estradiol and ICI 182,780, testing the hypothesis that ICI 182,780 antagonizes the action of estradiol in the fetal hypothalamus. Chronically catheterized ovine fetuses were infused for 48 h with: vehicle (Control, n = 6), 17β-estradiol 500 μg/kg/day (Estradiol, n = 4), ICI 182,780 5 μg/kg/day (ICI 5 μg, n = 4) and ICI 182,780 5 mg/kg/day (ICI 5 mg, n = 5). Fetal hypothalami were collected afterward, and gene expression was measured through microarray. Statistical analysis of transcriptomic data was performed with Bioconductor-R and Cytoscape software. Unexpectedly, 35% and 15.5% of the upregulated differentially expressed genes (DEG) by Estradiol significantly overlapped (P < 0.05) with upregulated DEG by ICI 5 mg and ICI 5 μg, respectively. For the downregulated DEG, these percentages were 29.9% and 15.5%, respectively. There was almost no overlap for DEG following opposite directions between Estradiol and ICI ICI 5 mg or ICI 5 μg. Furthermore, most of the genes in the estrogen signaling pathway - after activation of the epidermal growth factor receptor - followed the same direction in Estradiol, ICI 5 μg or ICI 5 mg compared to Control. In conclusion, estradiol and ICI 182,780 have estrogenic genomic effects in the developing brain, suggesting the possibility that the major action of estradiol on the fetal hypothalamus involves another receptor system rather than estrogen receptors.
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Affiliation(s)
- Maria Belen Rabaglino
- Department of Physiology and Functional GenomicsCollege of MedicineUniversity of FloridaGainesvilleFloridaUSA
| | - Maureen Keller‐Wood
- PharmacodynamicsCollege of PharmacyUniversity of FloridaGainesvilleFloridaUSA
| | - Charles E. Wood
- Department of Physiology and Functional GenomicsCollege of MedicineUniversity of FloridaGainesvilleFloridaUSA
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Post-hypoxia Invasion of the fetal brain by multidrug resistant Staphylococcus. Sci Rep 2017; 7:6458. [PMID: 28743956 PMCID: PMC5527097 DOI: 10.1038/s41598-017-06789-6] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2016] [Accepted: 06/19/2017] [Indexed: 01/12/2023] Open
Abstract
Herein we describe an association between activation of inflammatory pathways following transient hypoxia and the appearance of the multidrug resistant bacteria Staphylococcus simulans in the fetal brain. Reduction of maternal arterial oxygen tension by 50% over 30 min resulted in a subseiuent significant over-expression of genes associated with immune responses 24 h later in the fetal brain. The activated genes were consistent with stimulation by bacterial lipopolysaccharide; an influx of macrophages and appearance of live bacteria were found in these fetal brains. S. simulans was the predominant bacterial species in fetal brain after hypoxia, but was found in placenta of all animals. Strains of S. simulans from the placenta and fetal brain were equally highly resistant to multiple antibiotics including methicillin and had identical genome sequences. These results suggest that bacteria from the placenta invade the fetal brain after maternal hypoxia.
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Chang EI, Zárate MA, Rabaglino MB, Richards EM, Arndt TJ, Keller-Wood M, Wood CE. Ketamine decreases inflammatory and immune pathways after transient hypoxia in late gestation fetal cerebral cortex. Physiol Rep 2016; 4:4/6/e12741. [PMID: 27033443 PMCID: PMC4814891 DOI: 10.14814/phy2.12741] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2016] [Accepted: 02/23/2016] [Indexed: 12/27/2022] Open
Abstract
Transient hypoxia in pregnancy stimulates a physiological reflex response that redistributes blood flow and defends oxygen delivery to the fetal brain. We designed the present experiment to test the hypotheses that transient hypoxia produces damage of the cerebral cortex and that ketamine, an antagonist of NMDA receptors and a known anti‐inflammatory agent, reduces the damage. Late gestation, chronically catheterized fetal sheep were subjected to a 30‐min period of ventilatory hypoxia that decreased fetal PaO2 from 17 ± 1 to 10 ± 1 mmHg, or normoxia (PaO2 17 ± 1 mmHg), with or without pretreatment (10 min before hypoxia/normoxia) with ketamine (3 mg/kg, i.v.). One day (24 h) after hypoxia/normoxia, fetal cerebral cortex was removed and mRNA extracted for transcriptomics and systems biology analysis (n = 3–5 per group). Hypoxia stimulated a transcriptomic response consistent with a reduction in cellular metabolism and an increase in inflammation. Ketamine pretreatment reduced both of these responses. The inflammation response modeled with transcriptomic systems biology was validated by immunohistochemistry and showed increased abundance of microglia/macrophages after hypoxia in the cerebral cortical tissue that ketamine significantly reduced. We conclude that transient hypoxia produces inflammation of the fetal cerebral cortex and that ketamine, in a standard clinical dose, reduces the inflammation response.
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Affiliation(s)
- Eileen I Chang
- Department of Physiology and Functional Genomics, University of Florida College of Medicine, Gainesville, Florida
| | - Miguel A Zárate
- Department of Physiology and Functional Genomics, University of Florida College of Medicine, Gainesville, Florida
| | - Maria B Rabaglino
- CEPROCOR, National Scientific and Technical Research Council (CONICET), Córdoba, Argentina
| | - Elaine M Richards
- Department of Pharmacodynamics, University of Florida College of Pharmacy, Gainesville, Florida
| | - Thomas J Arndt
- Department of Physiology and Functional Genomics, University of Florida College of Medicine, Gainesville, Florida
| | - Maureen Keller-Wood
- Department of Pharmacodynamics, University of Florida College of Pharmacy, Gainesville, Florida
| | - Charles E Wood
- Department of Physiology and Functional Genomics, University of Florida College of Medicine, Gainesville, Florida
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Abstract
The fetal hypothalamus-pituitary-adrenal (HPA) axis is at the center of mechanisms controlling fetal readiness for birth, survival after birth and, in several species, determination of the timing of birth. Stereotypical increases in fetal HPA axis activity at the end of gestation are critical for preparing the fetus for successful transition to postnatal life. The fundamental importance in fetal development of the endogenous activation of this endocrine axis at the end of gestation has led to the use of glucocorticoids for reducing neonatal morbidity in premature infants. However, the choice of dose and repetition of treatments has been controversial, raising the possibility that excess glucocorticoid might program an increased incidence of adult disease (e.g., coronary artery disease and diabetes). We make the argument that because of the critical importance of the fetal HPA axis and its interaction with the maternal HPA axis, dysregulation of cortisol plasma concentrations or inappropriate manipulation pharmacologically can have negative consequences at the beginning of extrauterine life and for decades thereafter.
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Affiliation(s)
- Charles E Wood
- Department of Physiology and Functional Genomics, University of Florida College of Medicine, FL, USA
| | - Maureen Keller-Wood
- Department of Pharmacodynamics, University of Florida College of Pharmacy, FL, USA
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A question of cytokine signaling in the fetus. J Cereb Blood Flow Metab 2015; 35:1387. [PMID: 26082011 PMCID: PMC4640328 DOI: 10.1038/jcbfm.2015.135] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/18/2015] [Accepted: 05/18/2015] [Indexed: 11/09/2022]
Abstract
The study by Sadowska and colleagues, featured in this edition of Journal of Cerebral Blood Flow and Metabolism, provides compelling insight into a critical mechanism of signaling that links somatic and brain inflammatory pathways. Brain inflammation is often treated as an isolated event, but the work by Sadowska et al clearly demonstrate that interleukin 1β crosses the fetal blood brain barrier, and that the rate of transfer increases after cerebral ischemia. It is, perhaps, time to link blood-borne cytokine signaling with alterations in the course of fetal brain development, especially after transient fetal hypoxia.
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