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Dakroub F, Kobeissy F, Mondello S, Yang Z, Xu H, Sura L, Rossignol C, Albayram M, Rajderkar D, Wang K, Weiss MD. MicroRNAs as biomarkers of brain injury in neonatal encephalopathy: an observational cohort study. Sci Rep 2024; 14:6645. [PMID: 38503820 PMCID: PMC10951356 DOI: 10.1038/s41598-024-57166-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2023] [Accepted: 03/14/2024] [Indexed: 03/21/2024] Open
Abstract
Neonatal Encephalopathy (NE) is a major cause of lifelong disability and neurological complications in affected infants. Identifying novel diagnostic biomarkers in this population may assist in predicting MRI injury and differentiate neonates with NE from those with low-cord pH or healthy neonates and may help clinicians make real-time decisions. To compare the microRNA (miRNA) profiles between neonates with NE, healthy controls, and neonates with low cord pH. Moreover, miRNA concentrations were compared to brain injury severity in neonates with NE. This is a retrospective analysis of miRNA profiles from select samples in the biorepository and data registry at the University of Florida Health Gainesville. The Firefly miRNA assay was used to screen a total of 65 neurological miRNA targets in neonates with NE (n = 36), low cord pH (n = 18) and healthy controls (n = 37). Multivariate statistical techniques, including principal component analysis and orthogonal partial least squares discriminant analysis, and miRNA Enrichment Analysis and Annotation were used to identify miRNA markers and their pathobiological relevance. A set of 10 highly influential miRNAs were identified, which were significantly upregulated in the NE group compared to healthy controls. Of these, miR-323a-3p and mir-30e-5p displayed the highest fold change in expression levels. Moreover, miR-34c-5p, miR-491-5p, and miR-346 were significantly higher in the NE group compared to the low cord pH group. Furthermore, several miRNAs were identified that can differentiate between no/mild and moderate/severe injury in the NE group as measured by MRI. MiRNAs represent promising diagnostic and prognostic tools for improving the management of NE.
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Affiliation(s)
- Fatima Dakroub
- Department of Experimental Pathology, Immunology and Microbiology, Center for Infectious Diseases Research, American University of Beirut, Beirut, Lebanon
| | - Firas Kobeissy
- Center for Neurotrauma, MultiOmics and Biomarkers, Department of Neurobiology, Morehouse School of Medicine, Atlanta, GA, USA
| | - Stefania Mondello
- Department of Biomedical and Dental Sciences and Morphofunctional Imaging, University of Messina, Via Consolare Valeria 1, 98125, Messina, Italy
| | - Zhihui Yang
- Department of Emergency Medicine, University of Florida, 1149 Newell Drive, L3-166, Gainesville, FL, 32611, USA
| | - Haiyan Xu
- Department of Emergency Medicine, University of Florida, 1149 Newell Drive, L3-166, Gainesville, FL, 32611, USA
| | - Livia Sura
- Department of Pediatrics, University of Florida, 1600 SW Archer Road, Gainesville, FL, 32610-0296, USA
| | - Candace Rossignol
- Department of Pediatrics, University of Florida, 1600 SW Archer Road, Gainesville, FL, 32610-0296, USA
| | - Mehmet Albayram
- Department of Radiology, University of Florida, Gainesville, FL, 32610, USA
| | | | - Kevin Wang
- Center for Neurotrauma, MultiOmics and Biomarkers, Department of Neurobiology, Morehouse School of Medicine, Atlanta, GA, USA
- Brain Rehabilitation Research Center, Malcom Randall VA Medical Center, North Florida/South Georgia Veterans Health System, 1601 SW Archer Road, Gainesville, FL, 32608, USA
| | - Michael D Weiss
- Department of Pediatrics, University of Florida, 1600 SW Archer Road, Gainesville, FL, 32610-0296, USA.
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Amrein Almira A, Chen MW, El Demerdash N, Javdan C, Park D, Lee JK, Martin LJ. Proteasome localization and activity in pig brain and in vivo small molecule screening for activators. Front Cell Neurosci 2024; 18:1353542. [PMID: 38469354 PMCID: PMC10925635 DOI: 10.3389/fncel.2024.1353542] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2023] [Accepted: 02/06/2024] [Indexed: 03/13/2024] Open
Abstract
Introduction Loss of proteasome function, proteinopathy, and proteotoxicity may cause neurodegeneration across the human lifespan in several forms of brain injury and disease. Drugs that activate brain proteasomes in vivo could thus have a broad therapeutic impact in neurology. Methods Using pigs, a clinically relevant large animal with a functionally compartmental gyrencephalic cerebral cortex, we evaluated the localization and biochemical activity of brain proteasomes and tested the ability of small molecules to activate brain proteasomes. Results By Western blotting, proteasome protein subunit PSMB5 and PSMA3 levels were similar in different pig brain regions. Immunohistochemistry for PSMB5 showed localization in the cytoplasm (diffuse and particulate) and nucleus (cytoplasm < nucleus). Some PSMB5 immunoreactivity was colocalized with mitochondrial (voltage-gated anion channel and cyclophilin D) and cell death (Aven) proteins in the neuronal soma and neuropil in the neocortex of pig and human brains. In the nucleus, PSMB5 immunoreactivity was diffuse, particulate, and clustered, including perinucleolar decorations. By fluorogenic assay, proteasome chymotrypsin-like activities (CTL) in crude tissue soluble fractions were generally similar within eight different pig brain regions. Proteasome CTL activity in the hippocampus was correlated with activity in nasal mucosa biopsies. In pilot analyses of subcellular fractions of pig cerebral cortex, proteasome CTL activity was highest in the cytosol and then ~50% lower in nuclear fractions; ~15-20% of total CTL activity was in pure mitochondrial fractions. With in-gel activity assay, 26S-singly and -doubly capped proteasomes were the dominant forms in the pig cerebral cortex. With a novel in situ histochemical activity assay, MG132-inhibitable proteasome CTL activity was localized to the neuropil, as a mosaic, and to cell bodies, nuclei, and centrosome-like perinuclear satellites. In piglets treated intravenously with pyrazolone derivative and chlorpromazine over 24 h, brain proteasome CTL activity was modestly increased. Discussion This study shows that the proteasome in the pig brain has relative regional uniformity, prominent nuclear and perinuclear presence with catalytic activity, a mitochondrial association with activity, 26S-single cap dominance, and indications from small molecule systemic administration of pyrazolone derivative and chlorpromazine that brain proteasome function appears safely activable.
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Affiliation(s)
- Adriana Amrein Almira
- Department of Anesthesiology and Critical Care Medicine, Johns Hopkins University School of Medicine, Baltimore, MD, United States
| | - May W. Chen
- Departments of Pediatrics, Johns Hopkins University School of Medicine, Baltimore, MD, United States
| | - Nagat El Demerdash
- Department of Anesthesiology and Critical Care Medicine, Johns Hopkins University School of Medicine, Baltimore, MD, United States
| | - Cameron Javdan
- Department of Anesthesiology and Critical Care Medicine, Johns Hopkins University School of Medicine, Baltimore, MD, United States
| | - Dongseok Park
- Department of Pathology, Johns Hopkins University School of Medicine, Baltimore, MD, United States
| | - Jennifer K. Lee
- Department of Anesthesiology and Critical Care Medicine, Johns Hopkins University School of Medicine, Baltimore, MD, United States
| | - Lee J. Martin
- Department of Anesthesiology and Critical Care Medicine, Johns Hopkins University School of Medicine, Baltimore, MD, United States
- Department of Pathology, Johns Hopkins University School of Medicine, Baltimore, MD, United States
- Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD, United States
- Pathobiology Graduate Training Program, Johns Hopkins University School of Medicine, Baltimore, MD, United States
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Primiani CT, Lee JK, O’Brien CE, Chen MW, Perin J, Kulikowicz E, Santos P, Adams S, Lester B, Rivera-Diaz N, Olberding V, Niedzwiecki MV, Ritzl EK, Habela CW, Liu X, Yang ZJ, Koehler RC, Martin LJ. Hypothermic Protection in Neocortex Is Topographic and Laminar, Seizure Unmitigating, and Partially Rescues Neurons Depleted of RNA Splicing Protein Rbfox3/NeuN in Neonatal Hypoxic-Ischemic Male Piglets. Cells 2023; 12:2454. [PMID: 37887298 PMCID: PMC10605428 DOI: 10.3390/cells12202454] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2023] [Revised: 10/10/2023] [Accepted: 10/13/2023] [Indexed: 10/28/2023] Open
Abstract
The effects of hypothermia on neonatal encephalopathy may vary topographically and cytopathologically in the neocortex with manifestations potentially influenced by seizures that alter the severity, distribution, and type of neuropathology. We developed a neonatal piglet survival model of hypoxic-ischemic (HI) encephalopathy and hypothermia (HT) with continuous electroencephalography (cEEG) for seizures. Neonatal male piglets received HI-normothermia (NT), HI-HT, sham-NT, or sham-HT treatments. Randomized unmedicated sham and HI piglets underwent cEEG during recovery. Survival was 2-7 days. Normal and pathological neurons were counted in different neocortical areas, identified by cytoarchitecture and connectomics, using hematoxylin and eosin staining and immunohistochemistry for RNA-binding FOX-1 homolog 3 (Rbfox3/NeuN). Seizure burden was determined. HI-NT piglets had a reduced normal/total neuron ratio and increased ischemic-necrotic/total neuron ratio relative to sham-NT and sham-HT piglets with differing severities in the anterior and posterior motor, somatosensory, and frontal cortices. Neocortical neuropathology was attenuated by HT. HT protection was prominent in layer III of the inferior parietal cortex. Rbfox3 immunoreactivity distinguished cortical neurons as: Rbfox3-positive/normal, Rbfox3-positive/ischemic-necrotic, and Rbfox3-depleted. HI piglets had an increased Rbfox3-depleted/total neuron ratio in layers II and III compared to sham-NT piglets. Neuronal Rbfox3 depletion was partly rescued by HT. Seizure burdens in HI-NT and HI-HT piglets were similar. We conclude that the neonatal HI piglet neocortex has: (1) suprasylvian vulnerability to HI and seizures; (2) a limited neuronal cytopathological repertoire in functionally different regions that engages protective mechanisms with HT; (3) higher seizure burden, insensitive to HT, that is correlated with more panlaminar ischemic-necrotic neurons in the somatosensory cortex; and (4) pathological RNA splicing protein nuclear depletion that is sensitive to HT. This work demonstrates that HT protection of the neocortex in neonatal HI is topographic and laminar, seizure unmitigating, and restores neuronal depletion of RNA splicing factor.
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Affiliation(s)
- Christopher T. Primiani
- Department of Neurology, Johns Hopkins University School of Medicine, 558 Ross Building, 720 Rutland Avenue, Baltimore, MD 21205-2196, USA
| | - Jennifer K. Lee
- Department of Anesthesiology and Critical Care Medicine, Johns Hopkins University School of Medicine, 558 Ross Building, 720 Rutland Avenue, Baltimore, MD 21205-2196, USA; (J.K.L.); (E.K.); (V.O.); (M.V.N.)
| | - Caitlin E. O’Brien
- Department of Anesthesiology and Critical Care Medicine, Johns Hopkins University School of Medicine, 558 Ross Building, 720 Rutland Avenue, Baltimore, MD 21205-2196, USA; (J.K.L.); (E.K.); (V.O.); (M.V.N.)
| | - May W. Chen
- Department Pediatrics, Johns Hopkins University School of Medicine, 558 Ross Building, 720 Rutland Avenue, Baltimore, MD 21205-2196, USA
| | - Jamie Perin
- Department of Biostatistics and Epidemiology, Johns Hopkins University School of Medicine, 558 Ross Building, 720 Rutland Avenue, Baltimore, MD 21205-2196, USA
| | - Ewa Kulikowicz
- Department of Anesthesiology and Critical Care Medicine, Johns Hopkins University School of Medicine, 558 Ross Building, 720 Rutland Avenue, Baltimore, MD 21205-2196, USA; (J.K.L.); (E.K.); (V.O.); (M.V.N.)
| | - Polan Santos
- Department of Anesthesiology and Critical Care Medicine, Johns Hopkins University School of Medicine, 558 Ross Building, 720 Rutland Avenue, Baltimore, MD 21205-2196, USA; (J.K.L.); (E.K.); (V.O.); (M.V.N.)
| | - Shawn Adams
- Department of Anesthesiology and Critical Care Medicine, Johns Hopkins University School of Medicine, 558 Ross Building, 720 Rutland Avenue, Baltimore, MD 21205-2196, USA; (J.K.L.); (E.K.); (V.O.); (M.V.N.)
| | - Bailey Lester
- Department of Anesthesiology and Critical Care Medicine, Johns Hopkins University School of Medicine, 558 Ross Building, 720 Rutland Avenue, Baltimore, MD 21205-2196, USA; (J.K.L.); (E.K.); (V.O.); (M.V.N.)
| | - Natalia Rivera-Diaz
- Department of Anesthesiology and Critical Care Medicine, Johns Hopkins University School of Medicine, 558 Ross Building, 720 Rutland Avenue, Baltimore, MD 21205-2196, USA; (J.K.L.); (E.K.); (V.O.); (M.V.N.)
| | - Valerie Olberding
- Department of Anesthesiology and Critical Care Medicine, Johns Hopkins University School of Medicine, 558 Ross Building, 720 Rutland Avenue, Baltimore, MD 21205-2196, USA; (J.K.L.); (E.K.); (V.O.); (M.V.N.)
| | - Mark V. Niedzwiecki
- Department of Anesthesiology and Critical Care Medicine, Johns Hopkins University School of Medicine, 558 Ross Building, 720 Rutland Avenue, Baltimore, MD 21205-2196, USA; (J.K.L.); (E.K.); (V.O.); (M.V.N.)
| | - Eva K. Ritzl
- Department of Neurology, Johns Hopkins University School of Medicine, 558 Ross Building, 720 Rutland Avenue, Baltimore, MD 21205-2196, USA
| | - Christa W. Habela
- Department of Neurology, Johns Hopkins University School of Medicine, 558 Ross Building, 720 Rutland Avenue, Baltimore, MD 21205-2196, USA
| | - Xiuyun Liu
- Department of Anesthesiology and Critical Care Medicine, Johns Hopkins University School of Medicine, 558 Ross Building, 720 Rutland Avenue, Baltimore, MD 21205-2196, USA; (J.K.L.); (E.K.); (V.O.); (M.V.N.)
| | - Zeng-Jin Yang
- Department of Anesthesiology and Critical Care Medicine, Johns Hopkins University School of Medicine, 558 Ross Building, 720 Rutland Avenue, Baltimore, MD 21205-2196, USA; (J.K.L.); (E.K.); (V.O.); (M.V.N.)
| | - Raymond C. Koehler
- Department of Anesthesiology and Critical Care Medicine, Johns Hopkins University School of Medicine, 558 Ross Building, 720 Rutland Avenue, Baltimore, MD 21205-2196, USA; (J.K.L.); (E.K.); (V.O.); (M.V.N.)
| | - Lee J. Martin
- Department of Anesthesiology and Critical Care Medicine, Johns Hopkins University School of Medicine, 558 Ross Building, 720 Rutland Avenue, Baltimore, MD 21205-2196, USA; (J.K.L.); (E.K.); (V.O.); (M.V.N.)
- Department of Pathology, Johns Hopkins University School of Medicine, 558 Ross Building, 720 Rutland Avenue, Baltimore, MD 21205-2196, USA
- Department of Neuroscience, Johns Hopkins University School of Medicine, 558 Ross Building, 720 Rutland Avenue, Baltimore, MD 21205-2196, USA
- The Pathobiology Graduate Training Program, Johns Hopkins University School of Medicine, 558 Ross Building, 720 Rutland Avenue, Baltimore, MD 21205-2196, USA
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Andelius TCK, Bøgh N, Pedersen MV, Omann C, Andersen M, Andersen HB, Hjortdal VE, Pedersen M, Rasmussen MB, Kyng KJ, Henriksen TB. Early changes in cerebral metabolism after perinatal hypoxia-ischemia: a study in normothermic and hypothermic piglets. Front Pediatr 2023; 11:1167396. [PMID: 37325341 PMCID: PMC10264796 DOI: 10.3389/fped.2023.1167396] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/16/2023] [Accepted: 05/09/2023] [Indexed: 06/17/2023] Open
Abstract
Introduction Hypoxic ischemic encephalopathy (HIE) after a perinatal insult is a dynamic process that evolves over time. Therapeutic hypothermia (TH) is standard treatment for severe to moderate HIE. There is a lack of evidence on the temporal change and interrelation of the underlying mechanisms that constitute HIE under normal and hypothermic conditions. We aimed to describe early changes in intracerebral metabolism after a hypoxic-ischemic insult in piglets treated with and without TH and in controls. Methods Three devices were installed into the left hemisphere of 24 piglets: a probe measuring intracranial pressure, a probe measuring blood flow and oxygen tension, and a microdialysis catheter measuring lactate, glucose, glycerol, and pyruvate. After a standardized hypoxic ischemic insult, the piglets were randomized to either TH or normothermia. Results Glycerol, a marker of cell lysis, increased immediately after the insult in both groups. There was a secondary increase in glycerol in normothermic piglets but not in piglets treated with TH. Intracerebral pressure, blood flow, oxygen tension, and extracellular lactate remained stable during the secondary increase in glycerol. Conclusion This exploratory study depicted the development of the pathophysiological mechanisms in the hours following a perinatal hypoxic-ischemic insult with and without TH and controls.
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Affiliation(s)
- Ted C. K. Andelius
- Department of Pediatrics, Aarhus University Hospital, Aarhus, Denmark
- Department of Clinical Medicine, Faculty of Health, Aarhus University, Aarhus, Denmark
| | - Nikolaj Bøgh
- The MR Research Centre, Aarhus University, Aarhus, Denmark
| | - Mette V. Pedersen
- Department of Pediatrics, Aarhus University Hospital, Aarhus, Denmark
- Department of Clinical Medicine, Faculty of Health, Aarhus University, Aarhus, Denmark
| | - Camilla Omann
- Department of Cardiothoracic and Vascular Surgery, Aarhus University Hospital, Aarhus, Denmark
| | - Mads Andersen
- Department of Pediatrics, Aarhus University Hospital, Aarhus, Denmark
- Department of Clinical Medicine, Faculty of Health, Aarhus University, Aarhus, Denmark
| | - Hannah B. Andersen
- Department of Pediatrics, Aarhus University Hospital, Aarhus, Denmark
- Department of Clinical Medicine, Faculty of Health, Aarhus University, Aarhus, Denmark
| | - Vibeke E. Hjortdal
- Department of Cardiothoracic and Vascular Surgery, Aarhus University Hospital, Aarhus, Denmark
| | - Michael Pedersen
- Comparative Medicine Lab, Aarhus University Hospital, Aarhus, Denmark
| | - Martin B. Rasmussen
- Department of Pediatrics, Aarhus University Hospital, Aarhus, Denmark
- Department of Clinical Medicine, Faculty of Health, Aarhus University, Aarhus, Denmark
| | - Kasper J. Kyng
- Department of Pediatrics, Aarhus University Hospital, Aarhus, Denmark
- Department of Clinical Medicine, Faculty of Health, Aarhus University, Aarhus, Denmark
| | - Tine B. Henriksen
- Department of Pediatrics, Aarhus University Hospital, Aarhus, Denmark
- Department of Clinical Medicine, Faculty of Health, Aarhus University, Aarhus, Denmark
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Effects of Hypothermia and Allopurinol on Oxidative Status in a Rat Model of Hypoxic Ischemic Encephalopathy. Antioxidants (Basel) 2021; 10:antiox10101523. [PMID: 34679658 PMCID: PMC8533154 DOI: 10.3390/antiox10101523] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2021] [Accepted: 09/20/2021] [Indexed: 12/22/2022] Open
Abstract
Hypoxic ischemic encephalopathy (HIE) is one of the main causes of morbidity and mortality during the neonatal period, despite treatment with hypothermia. There is evidence that oxidative damage plays an important role in the pathophysiology of hypoxic-ischemic (HI) brain injury. Our aim was to investigate whether postnatal allopurinol administration in combination with hypothermia would reduce oxidative stress (OS) biomarkers in an animal model of HIE. Postnatal 10-day rat pups underwent unilateral HI of moderate severity. Pups were randomized into: Sham operated, hypoxic-ischemic (HI), HI + allopurinol (HIA), HI + hypothermia (HIH), and HI + hypothermia + allopurinol (HIHA). Biomarkers of OS and antioxidants were evaluated: GSH/GSSG ratio and carbonyl groups were tested in plasma. Total antioxidant capacity (TAC) was analyzed in plasma and cerebrospinal fluid, and 8-iso-prostaglandin F2α was measured in brain tissue. Plasma 2,2′–azinobis-(3-ethyl-benzothiazoline-6-sulfonic acid) (ABTS) levels were preserved in those groups that received allopurinol and dual therapy. In cerebrospinal fluid, only the HIA group presented normal ferric reducing ability of plasma (FRAP) levels. Protein oxidation and lipid peroxidation were significantly reduced in all groups treated with hypothermia and allopurinol, thus enhancing neuroprotection in HIE.
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Abstract
The cerebral microcirculation undergoes dynamic changes in parallel with the development of neurons, glia, and their energy metabolism throughout gestation and postnatally. Cerebral blood flow (CBF), oxygen consumption, and glucose consumption are as low as 20% of adult levels in humans born prematurely but eventually exceed adult levels at ages 3 to 11 years, which coincide with the period of continued brain growth, synapse formation, synapse pruning, and myelination. Neurovascular coupling to sensory activation is present but attenuated at birth. By 2 postnatal months, the increase in CBF often is disproportionately smaller than the increase in oxygen consumption, in contrast to the relative hyperemia seen in adults. Vascular smooth muscle myogenic tone increases in parallel with developmental increases in arterial pressure. CBF autoregulatory response to increased arterial pressure is intact at birth but has a more limited range with arterial hypotension. Hypoxia-induced vasodilation in preterm fetal sheep with low oxygen consumption does not sustain cerebral oxygen transport, but the response becomes better developed for sustaining oxygen transport by term. Nitric oxide tonically inhibits vasomotor tone, and glutamate receptor activation can evoke its release in lambs and piglets. In piglets, astrocyte-derived carbon monoxide plays a central role in vasodilation evoked by glutamate, ADP, and seizures, and prostanoids play a large role in endothelial-dependent and hypercapnic vasodilation. Overall, homeostatic mechanisms of CBF regulation in response to arterial pressure, neuronal activity, carbon dioxide, and oxygenation are present at birth but continue to develop postnatally as neurovascular signaling pathways are dynamically altered and integrated. © 2021 American Physiological Society. Compr Physiol 11:1-62, 2021.
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Deng C, Yi R, Fei M, Li T, Han Y, Wang H. Naringenin attenuates endoplasmic reticulum stress, reduces apoptosis, and improves functional recovery in experimental traumatic brain injury. Brain Res 2021; 1769:147591. [PMID: 34324877 DOI: 10.1016/j.brainres.2021.147591] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2020] [Revised: 07/09/2021] [Accepted: 07/23/2021] [Indexed: 11/15/2022]
Abstract
Traumatic brain injury (TBI) is a significant cause of disability and death worldwide. Accumulating evidence suggests that endoplasmic reticulum (ER) stress would be an important component in the pathogenesis of TBI. Although the neuroprotective effects of naringenin, a natural flavonoid isolated from citrus plants, have been confirmed in several neurological diseases, its mechanism of action in TBI needs further investigation. In ICR mice, we found that TBI induced elevated expression of ER stress marker proteins, including 78-kDa glucose-regulated protein (GRP78) and C/EBP homologous protein (CHOP) in the perilesional cortex, which peaked at 7 days and 3 days after TBI, respectively. The induction of ER stress-related proteins partly coincided with ER architectural changes at 3 days post-TBI, indicating ER stress activation in our TBI model. Our results also revealed that continuous naringenin administration ameliorated neurological dysfunction, cerebral edema, plasmalemma permeability, and neuron cell loss at day 3 after TBI. Further, Naringenin suppressed TBI-induced activation of the ER stress pathway (p-eIF2α, ATF4, and CHOP), oxidative stress and apoptosis on day 3 after TBI. In summary, our data suggest that naringenin could ameliorate TBI-induced secondary brain injury by pleiotropic effects, including ER stress attenuation.
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Affiliation(s)
- Chulei Deng
- Department of Neurosurgery, Jinling Hospital, The First School of Clinical Medicine, Southern Medical University, Nanjing 210002, PR China
| | - Renxin Yi
- Department of Neurosurgery, Jinling Hospital, Southeast University, School of Medicine, Nanjing 210002, PR China
| | - Maoxing Fei
- Department of Neurosurgery, Jinling Hospital, Nanjing Medical University, School of Medicine, Nanjing 210002, PR China
| | - Tao Li
- Department of Neurosurgery, Jinling Hospital, Nanjing Medical University, School of Medicine, Nanjing 210002, PR China
| | - Yanling Han
- Department of Neurosurgery, Jinling Hospital, School of Medicine, Nanjing University, Nanjing 210002, PR China
| | - Handong Wang
- Department of Neurosurgery, Jinling Hospital, School of Medicine, Nanjing University, Nanjing 210002, PR China.
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Liu D, Jiang D, Tekes A, Kulikowicz E, Martin LJ, Lee JK, Liu P, Qin Q. Multi-Parametric Evaluation of Cerebral Hemodynamics in Neonatal Piglets Using Non-Contrast-Enhanced Magnetic Resonance Imaging Methods. J Magn Reson Imaging 2021; 54:1053-1065. [PMID: 33955613 DOI: 10.1002/jmri.27638] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2021] [Revised: 03/31/2021] [Accepted: 04/01/2021] [Indexed: 12/20/2022] Open
Abstract
BACKGROUND Disruption of brain oxygen delivery and consumption after hypoxic-ischemic injury contributes to neonatal mortality and neurological impairment. Measuring cerebral hemodynamic parameters, including cerebral blood flow (CBF), oxygen extraction fraction (OEF), and cerebral metabolic rate of oxygen (CMRO2 ), is clinically important. PURPOSE Phase-contrast (PC), velocity-selective arterial spin labeling (VSASL), and T2 -relaxation-under-phase-contrast (TRUPC) are magnetic resonance imaging (MRI) techniques that have shown promising results in assessing cerebral hemodynamics in humans. We aimed to test their feasibility in quantifying CBF, OEF, and CMRO2 in piglets. STUDY TYPE Prospective. ANIMAL MODEL Ten neonatal piglets subacutely recovered from global hypoxia-ischemia (N = 2), excitotoxic brain injury (N = 6), or sham procedure (N = 2). FIELD STRENGTH/SEQUENCE VSASL, TRUPC, and PC MRI acquired at 3.0 T. ASSESSMENT Regional CBF was measured by VSASL. Global CBF was quantified by both PC and VSASL. TRUPC assessed OEF at the superior sagittal sinus (SSS) and internal cerebral veins (ICVs). CMRO2 was calculated from global CBF and SSS-derived OEF. End-tidal carbon dioxide (EtCO2 ) levels of the piglets were also measured. Brain damage was assessed in tissue sections postmortem by counting damaged neurons. STATISTICAL TESTS Spearman correlations were performed to evaluate associations among CBF (by PC or VSASL), OEF, CMRO2 , EtCO2 , and the pathological neuron counts. Paired t-test was used to compare OEF at SSS with OEF at ICV. RESULTS Global CBF was 32.1 ± 14.9 mL/100 g/minute and 30.9 ± 8.3 mL/100 g/minute for PC and VSASL, respectively, showing a significant correlation (r = 0.82, P < 0.05). OEF was 54.9 ± 8.8% at SSS and 46.1 ± 5.6% at ICV, showing a significant difference (P < 0.05). Global CMRO2 was 79.1 ± 26.2 μmol/100 g/minute and 77.2 ± 12.2 μmol/100 g/minute using PC and VSASL-derived CBF, respectively. EtCO2 correlated positively with PC-based CBF (r = 0.81, P < 0.05) but negatively with OEF at SSS (r = -0.84, P < 0.05). Relative CBF of subcortical brain regions and OEF at ICV did not significantly correlate, respectively, with the ratios of degenerating-to-total neurons (P = 0.30, P = 0.10). DATA CONCLUSION Non-contrast MRI can quantify cerebral hemodynamic parameters in normal and brain-injured neonatal piglets. LEVEL OF EVIDENCE 1 TECHNICAL EFFICACY STAGE: 2.
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Affiliation(s)
- Dapeng Liu
- The Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA.,F.M. Kirby Research Center for Functional Brain Imaging, Kennedy Krieger Institute, Baltimore, Maryland, USA
| | - Dengrong Jiang
- The Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Aylin Tekes
- The Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Ewa Kulikowicz
- Department of Anesthesiology and Critical Care Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Lee J Martin
- Department of Pathology, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Jennifer K Lee
- Department of Anesthesiology and Critical Care Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Peiying Liu
- The Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Qin Qin
- The Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA.,F.M. Kirby Research Center for Functional Brain Imaging, Kennedy Krieger Institute, Baltimore, Maryland, USA
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The Kynurenic Acid Analog SZR72 Enhances Neuronal Activity after Asphyxia but Is Not Neuroprotective in a Translational Model of Neonatal Hypoxic Ischemic Encephalopathy. Int J Mol Sci 2021; 22:ijms22094822. [PMID: 34062911 PMCID: PMC8125407 DOI: 10.3390/ijms22094822] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2021] [Revised: 04/28/2021] [Accepted: 04/29/2021] [Indexed: 11/17/2022] Open
Abstract
Hypoxic-ischemic encephalopathy (HIE) remains to be a major cause of long-term neurodevelopmental deficits in term neonates. Hypothermia offers partial neuroprotection warranting research for additional therapies. Kynurenic acid (KYNA), an endogenous product of tryptophan metabolism, was previously shown to be beneficial in rat HIE models. We sought to determine if the KYNA analog SZR72 would afford neuroprotection in piglets. After severe asphyxia (pHa = 6.83 ± 0.02, ΔBE = -17.6 ± 1.2 mmol/L, mean ± SEM), anesthetized piglets were assigned to vehicle-treated (VEH), SZR72-treated (SZR72), or hypothermia-treated (HT) groups (n = 6, 6, 6; Tcore = 38.5, 38.5, 33.5 °C, respectively). Compared to VEH, serum KYNA levels were elevated, recovery of EEG was faster, and EEG power spectral density values were higher at 24 h in the SZR72 group. However, instantaneous entropy indicating EEG signal complexity, depression of the visual evoked potential (VEP), and the significant neuronal damage observed in the neocortex, the putamen, and the CA1 hippocampal field were similar in these groups. In the caudate nucleus and the CA3 hippocampal field, neuronal damage was even more severe in the SZR72 group. The HT group showed the best preservation of EEG complexity, VEP, and neuronal integrity in all examined brain regions. In summary, SZR72 appears to enhance neuronal activity after asphyxia but does not ameliorate early neuronal damage in this HIE model.
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10
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Chen MW, Santos P, Kulikowicz E, Koehler RC, Lee JK, Martin LJ. Targeting the mitochondrial permeability transition pore for neuroprotection in a piglet model of neonatal hypoxic-ischemic encephalopathy. J Neurosci Res 2021; 99:1550-1564. [PMID: 33675112 DOI: 10.1002/jnr.24821] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2021] [Accepted: 02/17/2021] [Indexed: 11/07/2022]
Abstract
Neonatal hypoxic-ischemic encephalopathy (HIE) causes significant morbidity despite treatment with therapeutic hypothermia. Mitochondrial dysfunction may drive the mechanisms underlying neuronal cell death, thereby making mitochondria prime targets for neuroprotection. The mitochondrial permeability transition pore (mPTP) is one such target within mitochondria. In adult animal models, mPTP inhibition is neuroprotective. However, evidence for mPTP inhibition in neonatal models of neurologic disease is less certain. We tested the therapeutic efficacy of the mPTP small molecule inhibitor GNX-4728 and examined the developmental presence of brain mPTP proteins for drug targeting in a neonatal piglet model of hypoxic-ischemic brain injury. Male neonatal piglets were randomized to hypoxia-ischemia (HI) or sham procedure with GNX-4728 (15 mg/kg, IV) or vehicle (saline/cyclodextrin/DMSO, IV). GNX-4728 was administered as a single dose within 5 min after resuscitation from bradycardic arrest. Normal, ischemic, and injured neurons were counted in putamen and somatosensory cortex using hematoxylin and eosin staining. In separate neonatal and juvenile pigs, western blots of putamen mitochondrial-enriched fractions were used to evaluate mitochondrial integrity and the presence of mPTP proteins. We found that a single dose of GNX-4728 did not protect putamen and cortical neurons from cell death after HI. However, loss of mitochondrial matrix integrity occurred within 6h after HI, and while mPTP components are present in the neonatal brain their levels were significantly different compared to that of a mature juvenile brain. Thus, the neonatal brain mPTP may not be a good target for current neurotherapeutic drugs that are developed based on adult mitochondria.
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Affiliation(s)
- May W Chen
- Division of Neonatology, Department of Pediatrics, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Polan Santos
- Department of Anesthesiology and Critical Care Medicine, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Ewa Kulikowicz
- Department of Anesthesiology and Critical Care Medicine, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Raymond C Koehler
- Department of Anesthesiology and Critical Care Medicine, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Jennifer K Lee
- Department of Anesthesiology and Critical Care Medicine, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Lee J Martin
- Department of Neuroscience and Pathology, Johns Hopkins University School of Medicine, Baltimore, MD, USA
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Wang B, Kulikowicz E, Lee JK, Koehler RC, Yang ZJ. Sulforaphane Protects Piglet Brains from Neonatal Hypoxic-Ischemic Injury. Dev Neurosci 2020; 42:124-134. [PMID: 33302269 DOI: 10.1159/000511888] [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] [Received: 06/25/2020] [Accepted: 09/22/2020] [Indexed: 12/30/2022] Open
Abstract
The striatal, primary sensorimotor cortical, and thalamic neurons are highly vulnerable to hypoxia-ischemia (HI) in term newborns. In a piglet model of HI that exhibits similar selective regional vulnerability, we tested the hypothesis that early treatment with sulforaphane, an activator of the Nrf2 transcription factor, protects vulnerable neurons from HI injury. Anesthetized piglets (aged 3-7 days) were subjected to 45 min of hypoxia and 7 min of airway occlusion. At 15 min after resuscitation, the piglets received intravenous vehicle or sulforaphane. At 4 days of recovery, the density of viable neurons in the putamen of vehicle-treated piglets was 31 ± 34% (±SD) that of sham-operated controls. Treatment with sulforaphane significantly increased viability to 77 ± 31%. In the sensorimotor cortex, neuronal viability was also increased; it was 59 ± 35% in the vehicle-treated and 89 ± 15% in the sulforaphane-treated animals. Treatment with sulforaphane increased the nuclear Nrf2 and γ-glu-tamylcysteine synthetase expression at 6 h of recovery in these regions. We conclude that systemic administration of sulforaphane 15 min after HI can induce the translocation of Nrf2 to the nucleus, increase expression of an enzyme involved in glutathione synthesis, and salvage neurons in the highly vulnerable putamen and sensorimotor cortex in a large-animal model of HI. Therefore, targeting Nrf2 activation soon after recovery from HI is a feasible approach for neuroprotection in the newborn brain.
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Affiliation(s)
- Bing Wang
- Department of Anesthesiology and Critical Care Medicine, Johns Hopkins University, Baltimore, Maryland, USA
| | - Ewa Kulikowicz
- Department of Anesthesiology and Critical Care Medicine, Johns Hopkins University, Baltimore, Maryland, USA
| | - Jennifer K Lee
- Department of Anesthesiology and Critical Care Medicine, Johns Hopkins University, Baltimore, Maryland, USA
| | - Raymond C Koehler
- Department of Anesthesiology and Critical Care Medicine, Johns Hopkins University, Baltimore, Maryland, USA
| | - Zeng-Jin Yang
- Department of Anesthesiology and Critical Care Medicine, Johns Hopkins University, Baltimore, Maryland, USA,
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12
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O'Brien CE, Santos PT, Kulikowicz E, Lee JK, Koehler RC, Martin LJ. Neurologic effects of short-term treatment with a soluble epoxide hydrolase inhibitor after cardiac arrest in pediatric swine. BMC Neurosci 2020; 21:43. [PMID: 33129262 PMCID: PMC7603774 DOI: 10.1186/s12868-020-00596-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2020] [Accepted: 10/09/2020] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Cardiac arrest (CA) is the most common cause of acute neurologic insult in children. Many survivors have significant neurocognitive deficits at 1 year of recovery. Epoxyeicosatrienoic acids (EETs) are multifunctional endogenous lipid signaling molecules that are involved in brain pathobiology and may be therapeutically relevant. However, EETs are rapidly metabolized to less active dihydroxyeicosatrienoic acids by soluble epoxide hydrolase (sEH), limiting their bioavailability. We hypothesized that sEH inhibition would improve outcomes after CA in an infant swine model. Male piglets (3-4 kg, 2 weeks old) underwent hypoxic-asphyxic CA. After resuscitation, they were randomized to intravenous treatment with an sEH inhibitor (TPPU, 1 mg/kg; n = 8) or vehicle (10% poly(ethylene glycol); n = 9) administered at 30 min and 24 h after return of spontaneous circulation. Two sham-operated groups received either TPPU (n = 9) or vehicle (n = 8). Neurons were counted in hematoxylin- and eosin-stained sections from putamen and motor cortex in 4-day survivors. RESULTS Piglets in the CA + vehicle groups had fewer neurons than sham animals in both putamen and motor cortex. However, the number of neurons after CA did not differ between vehicle- and TPPU-treated groups in either anatomic area. Further, 20% of putamen neurons in the Sham + TPPU group had abnormal morphology, with cell body attrition and nuclear condensation. TPPU treatment also did not reduce neurologic deficits. CONCLUSION Treatment with an sEH inhibitor at 30 min and 24 h after resuscitation from asphyxic CA does not protect neurons or improve acute neurologic outcomes in piglets.
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Affiliation(s)
- Caitlin E O'Brien
- Department of Anesthesiology and Critical Care Medicine, Johns Hopkins University School of Medicine, 1800 Orleans Street, Bloomberg Children's Center Suite 6302, Baltimore, MD, 21287, USA.
| | - Polan T Santos
- Department of Anesthesiology and Critical Care Medicine, Johns Hopkins University School of Medicine, 1800 Orleans Street, Bloomberg Children's Center Suite 6302, Baltimore, MD, 21287, USA
| | - Ewa Kulikowicz
- Department of Anesthesiology and Critical Care Medicine, Johns Hopkins University School of Medicine, 1800 Orleans Street, Bloomberg Children's Center Suite 6302, Baltimore, MD, 21287, USA
| | - Jennifer K Lee
- Department of Anesthesiology and Critical Care Medicine, Johns Hopkins University School of Medicine, 1800 Orleans Street, Bloomberg Children's Center Suite 6302, Baltimore, MD, 21287, USA
- Pathobiology Graduate Training Program, Johns Hopkins University School of Medicine, 1800 Orleans Street, Bloomberg Children's Center Suite 6302, Baltimore, MD, 21287, USA
| | - Raymond C Koehler
- Department of Anesthesiology and Critical Care Medicine, Johns Hopkins University School of Medicine, 1800 Orleans Street, Bloomberg Children's Center Suite 6302, Baltimore, MD, 21287, USA
| | - Lee J Martin
- Department of Pathology, Johns Hopkins University School of Medicine, 600 N. Wolfe Street, Baltimore, MD, 21287, USA
- Pathobiology Graduate Training Program, Johns Hopkins University School of Medicine, 1800 Orleans Street, Bloomberg Children's Center Suite 6302, Baltimore, MD, 21287, USA
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13
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Perrotta I. The microscopic anatomy of endothelial cells in human atherosclerosis: Focus on ER and mitochondria. J Anat 2020; 237:1015-1025. [PMID: 32735733 DOI: 10.1111/joa.13281] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2020] [Revised: 06/30/2020] [Accepted: 06/30/2020] [Indexed: 12/15/2022] Open
Abstract
Once regarded merely as a bland lipid storage disease consequence of aging, atherosclerosis is currently considered a slow and continuous inflammatory process (partially controllable by treatment) with complex etiology involving a multitude of genetic and environmental risk factors which ultimately result in the formation of the plaque. The vascular endothelium, a monolayer of endothelial cells (ECs), is an important regulatory "organ" critical for cardiovascular homeostasis in health which also contributes significantly to the pathomechanisms of several disease states, including atherosclerosis. Over the years, there has been evidence highlighting the central role of endoplasmic reticulum (ER) in the maintenance of endothelial function and perturbations in ER biology have been proposed to adversely affect a diverse range of endothelial functions. Of particular interest is the evidence that under certain pathophysiological circumstances, abnormal ER ultrastructure correlates with altered ER function and signaling and can contribute to cell injury and apoptosis. Therefore, the ultrastructural traits of ER membranes can have important implications not only for their functional bearings but also for the etiology and pathophysiology of diverse human disorders. With regard to atherosclerosis, the focus of ER research has been centered on the molecular signals originated from the ER to manage conditions of stress, leaving the fine structure of this organelle an almost unexplored (but promising) area of studies. There is, also, increasing evidence that mitochondrial dysfunction plays a critical role in promoting cell apoptosis, inflammation, and oxidative stress, thereby contributing to atheroma growth. It is within this context that the present study has been undertaken to investigate the microscopic architecture of ECs in human atherosclerosis and to determine whether the potential structural abnormalities of ER and mitochondria may play a central pathogenic role in atherogenesis or may merely reflect the condition of a tissue whose integrity has already been disturbed or destroyed. For this purpose, transmission electron microscopy (TEM) remains a powerful technique that can not only provide information about the ultrastructural state of cell organelles but also allow the correlation between different subcellular alterations indicative of a certain pathophysiological condition and cellular response. The present study expands the spectrum of ultrastructural defects known to exist in human atherosclerosis and suggests that ER alterations may be of great importance in the pathogenesis of the disease. The architectural changes of ER may be considered early pathological events that precede any overt histologic abnormalities in the vascular endothelium and its subcellular organelles, primarily the mitochondrial pool.
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Affiliation(s)
- Ida Perrotta
- Centre for Microscopy and Microanalysis, Transmission Electron Microscopy Laboratory, Department of Biology, Ecology and Earth Sciences (Di.B.E.S.T.), University of Calabria, Arcavacata di Rende, Italy
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14
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Deng K, Li Y, Xiao M, Wang F, Zhou P, Zhang W, Heep A, Li X. Lycium ruthenicum Murr polysaccharide protects cortical neurons against oxygen-glucose deprivation/reperfusion in neonatal hypoxic-ischemic encephalopathy. Int J Biol Macromol 2020; 158:562-568. [PMID: 32380112 DOI: 10.1016/j.ijbiomac.2020.04.122] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2019] [Revised: 04/11/2020] [Accepted: 04/18/2020] [Indexed: 02/08/2023]
Abstract
Neonatal hypoxic-ischemic encephalopathy (HIE) is a complex condition that remains the leading cause of mortality and morbidity among infants. Polysaccharide has been reported to possess diverse biological activities, however, the neuro-protective activity of polysaccharide isolated from Lycium ruthenicum remains unknown so far. However, the role of Lycium ruthenicum polysaccharide 3 (LRP3) in HIE has not been evaluated. Herein, we investigated the effect of LRP3 on oxygen-glucose deprivation/reoxygenation (OGD/R)-induced primary cortical neurons. Our results demonstrated that LRP3 significantly improved the cell viability of OGD/R-induced cortical neurons. The OGD/R-caused increase in ROS production and decrease in the activities of anti-oxidative enzymes including catalase (CAT), superoxide dismutase (SOD) and glutathione peroxidase (GPx) were mitigated by LRP3. Besides, the caspase-3 activity in OGD/R-induced cortical neurons was markedly decreased after LRP3 treatment. The increased bax expression and decreased bcl-2 expression caused by OGD/R stimulation were alleviated by pretreatment with LRP3. In addition, LRP3 significantly induced the expressions of nuclear factor erythroid 2-related factor (Nrf2) and heme oxygenase-1 (HO-1) in OGD/R-induced cortical neurons. However, inhibition of Nrf2/HO-1 signaling pathway through transfection with siRNA targeting Nrf2 reversed the protective effects of LRP3. In conclusion, LRP3 exerts a neuroprotective effect against OGD/R-induced neuronal injury in rat primary cortical neurons.
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Affiliation(s)
- Kewei Deng
- Department of Neonatology, Northwest Women's and Children's Hospital, Xi'an 710061, PR China
| | - Yanling Li
- Department of Neonatology, Qujiang Maternity Hospital, Xi'an 710060, PR China
| | - Mi Xiao
- Department of Neonatology, the First Affiliated Hospital of Xi'an Jiaotong University, Xi'an 710061, PR China
| | - Fanghui Wang
- Department of Neonatology, the First Affiliated Hospital of Xi'an Jiaotong University, Xi'an 710061, PR China
| | - Ping Zhou
- Clinical Laboratory, the First Affiliated Hospital of Xi'an Jiaotong University, Xi'an 710061, PR China
| | - Wei Zhang
- Department of Neonatology, the First Affiliated Hospital of Xi'an Jiaotong University, Xi'an 710061, PR China
| | - Axel Heep
- Neonatal Unit, Southmead Hospital, North Bristol NHS Trust, Bristol, United Kingdom
| | - Xiaoquan Li
- Department of Neonatology, the First Affiliated Hospital of Xi'an Jiaotong University, Xi'an 710061, PR China.
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15
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Oxygen for respiratory support of moderate and late preterm and term infants at birth: Is air best? Semin Fetal Neonatal Med 2020; 25:101074. [PMID: 31843378 DOI: 10.1016/j.siny.2019.101074] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Oxygen has been used for newborn infant resuscitation for more than two centuries. In the last two decades, concerns about oxidative stress and injury have changed this practice. Air (FiO2 0.21) is now preferred as the starting point for respiratory support of infants 34 weeks gestation and above. These recommendations are derived from studies that were conducted on asphyxiated, term infants, recruited more than 10 years ago using strategies that are not commonly used today. The applicability of these recommendations to current practice, is uncertain. In addition, whether initiating respiratory support with air for infants with pulmonary disorders provides sufficient oxygenation is also unclear. This review will address these concerns and provide suggestions for future steps to address knowledge and practice gaps.
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16
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Kim BW, Jeong YE, Wong M, Martin LJ. DNA damage accumulates and responses are engaged in human ALS brain and spinal motor neurons and DNA repair is activatable in iPSC-derived motor neurons with SOD1 mutations. Acta Neuropathol Commun 2020; 8:7. [PMID: 32005289 PMCID: PMC6995159 DOI: 10.1186/s40478-019-0874-4] [Citation(s) in RCA: 43] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2019] [Accepted: 12/17/2019] [Indexed: 12/12/2022] Open
Abstract
DNA damage is implicated in the pathogenesis of amyotrophic lateral sclerosis (ALS). However, relationships between DNA damage accumulation, DNA damage response (DDR), and upper and lower motor neuron vulnerability in human ALS are unclear; furthermore, it is unknown whether epigenetic silencing of DNA repair pathways contributes to ALS pathogenesis. We tested the hypotheses that DNA damage accumulates in ALS motor neurons along with diminished DDR, and that DNA repair genes undergo hypermethylation. Human postmortem CNS tissue was obtained from ALS cases (N = 34) and age-matched controls without neurologic disease (N = 15). Compared to age-matched controls, abasic sites accumulated in genomic DNA of ALS motor cortex and laser capture microdissection-acquired spinal motor neurons but not in motor neuron mitochondrial DNA. By immunohistochemistry, DNA damage accumulated significantly in upper and lower motor neurons in ALS cases as single-stranded DNA and 8-hydroxy-deoxyguanosine (OHdG) compared to age-matched controls. Significant DDR was engaged in ALS motor neurons as evidenced by accumulation of c-Abl, nuclear BRCA1, and ATM activation. DNA damage and DDR were present in motor neurons at pre-attritional stages and throughout the somatodendritic attritional stages of neurodegeneration. Motor neurons with DNA damage were also positive for activated p53 and cleaved caspase-3. Gene-specific promoter DNA methylation pyrosequencing identified the DNA repair genes Ogg1, Apex1, Pnkp and Aptx as hypomethylated in ALS. In human induced-pluripotent stem cell (iPSC)-derived motor neurons with familial ALS SOD1 mutations, DNA repair capacity was similar to isogenic control motor neurons. Our results show that vulnerable neurons in human ALS accumulate DNA damage, and contrary to our hypothesis, strongly activate and mobilize response effectors and DNA repair genes. This DDR in ALS motor neurons involves recruitment of c-Abl and BRCA1 to the nucleus in vivo, and repair of DNA double-strand breaks in human ALS motor neurons with SOD1 mutations in cell culture.
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Affiliation(s)
- Byung Woo Kim
- Department of Pathology, Johns Hopkins University School of Medicine, 558 Ross Building, 720 Rutland Avenue, Baltimore, MD, 21205-2196, USA
- Division of Neuropathology, the Pathobiology Graduate Training Program, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Ye Eun Jeong
- Division of Neuropathology, the Pathobiology Graduate Training Program, Johns Hopkins University School of Medicine, Baltimore, MD, USA
- Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Margaret Wong
- Department of Pathology, Johns Hopkins University School of Medicine, 558 Ross Building, 720 Rutland Avenue, Baltimore, MD, 21205-2196, USA
| | - Lee J Martin
- Department of Pathology, Johns Hopkins University School of Medicine, 558 Ross Building, 720 Rutland Avenue, Baltimore, MD, 21205-2196, USA.
- Division of Neuropathology, the Pathobiology Graduate Training Program, Johns Hopkins University School of Medicine, Baltimore, MD, USA.
- Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD, USA.
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17
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Santos PT, O'Brien CE, Chen MW, Hopkins CD, Adams S, Kulikowicz E, Singh R, Koehler RC, Martin LJ, Lee JK. Proteasome Biology Is Compromised in White Matter After Asphyxic Cardiac Arrest in Neonatal Piglets. J Am Heart Assoc 2019; 7:e009415. [PMID: 30371275 PMCID: PMC6474957 DOI: 10.1161/jaha.118.009415] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Background Neurological deficits in hypoxic‐ischemic encephalopathy, even with therapeutic hypothermia, are partially attributed to white matter injury. We theorized that proteasome insufficiency contributes to white matter injury. Methods and Results Neonatal piglets received hypoxia‐ischemia (HI) or sham procedure with normothermia, hypothermia, or hypothermia+rewarming. Some received a proteasome activator drug (oleuropein) or white matter–targeted, virus‐mediated proteasome knockdown. We measured myelin oligodendrocyte glycoprotein, proteasome subunit 20S (P20S), proteasome activity, and carbonylated and ubiquitinated protein levels in white matter and cerebral cortex. HI reduced myelin oligodendrocyte glycoprotein levels regardless of temperature, and myelin oligodendrocyte glycoprotein loss was associated with increased ubiquitinated and carbonylated protein levels. Ubiquitinated and carbonyl‐damaged proteins increased in white matter 29 hours after HI during hypothermia to exceed levels at 6 to 20 hours. In cortex, ubiquitinated proteins decreased. Ubiquitinated and carbonylated protein accumulation coincided with lower P20S levels in white matter; P20S levels also decreased in cerebral cortex. However, proteasome activity in white matter lagged behind that in cortex 29 hours after HI during hypothermia. Systemic oleuropein enhanced white matter P20S and protected the myelin, whereas proteasome knockdown exacerbated myelin oligodendrocyte glycoprotein loss and ubiquitinated protein accumulation after HI. At the cellular level, temperature and HI interactively affected macroglial P20S enrichment in subcortical white matter. Rewarming alone increased macroglial P20S immunoreactivity, but this increase was blocked by HI. Conclusions Oxidized and ubiquitinated proteins accumulate with HI‐induced white matter injury. Proteasome insufficiency may drive this injury. Hypothermia did not prevent myelin damage, protect the proteasome, or preserve oxidized and ubiquitinated protein clearance after HI.
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Affiliation(s)
- Polan T Santos
- 1 Department of Anesthesiology and Critical Care Medicine Johns Hopkins University Baltimore MD
| | - Caitlin E O'Brien
- 1 Department of Anesthesiology and Critical Care Medicine Johns Hopkins University Baltimore MD
| | - May W Chen
- 2 Division of Neonatology Department of Pediatrics Johns Hopkins University Baltimore MD
| | - C Danielle Hopkins
- 1 Department of Anesthesiology and Critical Care Medicine Johns Hopkins University Baltimore MD
| | - Shawn Adams
- 1 Department of Anesthesiology and Critical Care Medicine Johns Hopkins University Baltimore MD
| | - Ewa Kulikowicz
- 1 Department of Anesthesiology and Critical Care Medicine Johns Hopkins University Baltimore MD
| | - Rashmi Singh
- 1 Department of Anesthesiology and Critical Care Medicine Johns Hopkins University Baltimore MD
| | - Raymond C Koehler
- 1 Department of Anesthesiology and Critical Care Medicine Johns Hopkins University Baltimore MD
| | - Lee J Martin
- 3 Department of Pathology Johns Hopkins University Baltimore MD
| | - Jennifer K Lee
- 1 Department of Anesthesiology and Critical Care Medicine Johns Hopkins University Baltimore MD
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18
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Wu D, Martin LJ, Northington FJ, Zhang J. Oscillating-gradient diffusion magnetic resonance imaging detects acute subcellular structural changes in the mouse forebrain after neonatal hypoxia-ischemia. J Cereb Blood Flow Metab 2019; 39:1336-1348. [PMID: 29436246 PMCID: PMC6668516 DOI: 10.1177/0271678x18759859] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
The recently developed oscillating-gradient diffusion MRI (OG-dMRI) technique extends our ability to examine brain structures at different spatial scales. In this study, we investigated the sensitivity of OG-dMRI in detecting cellular and subcellular structural changes in a mouse model of neonatal hypoxia ischemia (HI). Neonatal mice received unilateral HI injury or sham injury at postnatal day 10, followed by in vivo T2-weighted and diffusion MRI of the brains at 3-6 h and 24 h after HI. Apparent diffusion coefficient (ADC) maps were acquired using conventional pulsed-gradient dMRI (PG-dMRI) and OG-dMRI with oscillating frequencies from 50 to 200 Hz. Pathology at cellular and subcellular levels was evaluated using neuronal, glial, and mitochondrial markers. We found significantly higher rates of ADC increase with oscillating frequencies (ΔfADC) in the ipsilateral edema region, compared to the contralateral side, starting as early as 3 h after HI. Even in injured regions that showed no apparent change in PG-ADC or pseudo-normalized PG-ADC measurements, ΔfADC remained significantly elevated. Histopathology showed swelling of sub-cellular structures in these regions with no apparent whole-cell level change. These results suggest that OG-dMRI is sensitive to subcellular structural changes in the brain after HI and is less susceptible to pseudo-normalization than PG-dMRI.
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Affiliation(s)
- Dan Wu
- 1 Key Laboratory for Biomedical Engineering of Ministry of Education, College of Biomedical Engineering & Instrument Science, Zhejiang University, Hangzhou, China.,2 Department of Radiology, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Lee J Martin
- 3 Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD, USA.,4 Department of Pathology, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Frances J Northington
- 5 Department of Pediatrics, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Jiangyang Zhang
- 6 Department of Radiology, New York University School of Medicine, New York, NY, USA
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19
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Martin LJ, Wong M, Hanaford A. Neonatal Brain Injury and Genetic Causes of Adult-Onset Neurodegenerative Disease in Mice Interact With Effects on Acute and Late Outcomes. Front Neurol 2019; 10:635. [PMID: 31275228 PMCID: PMC6591316 DOI: 10.3389/fneur.2019.00635] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2018] [Accepted: 05/30/2019] [Indexed: 12/27/2022] Open
Abstract
Neonatal brain damage and age-related neurodegenerative disease share many common mechanisms of injury involving mitochondriopathy, oxidative stress, excitotoxicity, inflammation, and neuronal cell death. We hypothesized that genes causing adult-onset neurodegeneration can influence acute outcome after CNS injury at immaturity and on the subsequent development of chronic disability after early-life brain injury. In two different transgenic (Tg) mouse models of adult-onset neurodegenerative disease, a human A53T-α-synuclein (hαSyn) model of Parkinson's disease (PD) and a human G93A-superoxide dismutase-1(hSOD1) model of amyotrophic lateral sclerosis (ALS), mortality and survivor morbidity were significantly greater than non-Tg mice and a Tg mouse model of Alzheimer's disease after neonatal traumatic brain injury (TBI). Acutely after brain injury, hαSyn neonatal mice showed a marked enhancement of protein oxidative damage in forebrain, brain regional mitochondrial oxidative metabolism, and mitochondriopathy. Extreme protein oxidative damage was also observed in neonatal mutant SOD1 mice after TBI. At 1 month of age, neuropathology in forebrain, midbrain, and brainstem of hαSyn mice with neonatal TBI was greater compared to sham hαSyn mice. Surviving hαSyn mice with TBI showed increased hαSyn aggregation and nitration and developed adult-onset disease months sooner and died earlier than non-injured hαSyn mice. Surviving hSOD1 mice with TBI also developed adult-onset disease and died sooner than non-injured hSOD1 mice. We conclude that mutant genes causing PD and ALS in humans have significant impact on mortality and morbidity after early-life brain injury and on age-related disease onset and proteinopathy in mice. This study provides novel insight into genetic determinants of poor outcomes after acute injury to the neonatal brain and how early-life brain injury can influence adult-onset neurodegenerative disease during aging.
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Affiliation(s)
- Lee J Martin
- Division of Neuropathology, Department of Pathology, Johns Hopkins University School of Medicine, Baltimore, MD, United States.,Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD, United States.,Pathobiology Graduate Training Program, Johns Hopkins University School of Medicine, Baltimore, MD, United States
| | - Margaret Wong
- Division of Neuropathology, Department of Pathology, Johns Hopkins University School of Medicine, Baltimore, MD, United States
| | - Allison Hanaford
- Pathobiology Graduate Training Program, Johns Hopkins University School of Medicine, Baltimore, MD, United States
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O'Brien CE, Santos PT, Kulikowicz E, Reyes M, Koehler RC, Martin LJ, Lee JK. Hypoxia-Ischemia and Hypothermia Independently and Interactively Affect Neuronal Pathology in Neonatal Piglets with Short-Term Recovery. Dev Neurosci 2019; 41:17-33. [PMID: 31108487 DOI: 10.1159/000496602] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2018] [Accepted: 01/06/2019] [Indexed: 12/25/2022] Open
Abstract
Therapeutic hypothermia is the standard of clinical care for moderate neonatal hypoxic-ischemic encephalopathy. We investigated the independent and interactive effects of hypoxia-ischemia (HI) and temperature on neuronal survival and injury in basal ganglia and cerebral cortex in neonatal piglets. Male piglets were randomized to receive HI injury or sham procedure followed by 29 h of normothermia, sustained hypothermia induced at 2 h, or hypothermia with rewarming during fentanyl-nitrous oxide anesthesia. Viable and injured neurons and apoptotic profiles were counted in the anterior putamen, posterior putamen, and motor cortex at 29 h after HI injury or sham procedure. Terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) identified genomic DNA fragmentation to confirm cell death. Though hypothermia after HI preserved viable neurons in the anterior and posterior putamen, hypothermia prevented neuronal injury in only the anterior putamen. Hypothermia initiated 2 h after injury did not protect against apoptotic cell death in either the putamen or motor cortex, and rewarming from hypothermia was associated with increased apoptosis in the motor cortex. In non-HI shams, sustained hypothermia during anesthesia was associated with neuronal injury and corresponding viable neuron loss in the anterior putamen and motor cortex. TUNEL confirmed increased neurodegeneration in the putamen of hypothermic shams. Anesthetized, normothermic shams did not show abnormal neuronal cytopathology in the putamen or motor cortex, thereby demonstrating minimal contribution of the anesthetic regimen to neuronal injury during normothermia. We conclude that the efficacy of hypothermic protection after HI is region specific and that hypothermia during anesthesia in the absence of HI may be associated with neuronal injury in the developing brain. Studies examining the potential interactions between hypothermia and anesthesia, as well as with longer durations of hypothermia, are needed.
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Affiliation(s)
- Caitlin E O'Brien
- Department of Anesthesiology and Critical Care Medicine, Johns Hopkins University, Baltimore, Maryland, USA,
| | - Polan T Santos
- Department of Anesthesiology and Critical Care Medicine, Johns Hopkins University, Baltimore, Maryland, USA
| | - Ewa Kulikowicz
- Department of Anesthesiology and Critical Care Medicine, Johns Hopkins University, Baltimore, Maryland, USA
| | - Michael Reyes
- Department of Anesthesiology and Critical Care Medicine, Johns Hopkins University, Baltimore, Maryland, USA
| | - Raymond C Koehler
- Department of Anesthesiology and Critical Care Medicine, Johns Hopkins University, Baltimore, Maryland, USA
| | - Lee J Martin
- Department of Pathology, Johns Hopkins University, Baltimore, Maryland, USA.,Pathobiology Graduate Training Program, Johns Hopkins University, Baltimore, Maryland, USA
| | - Jennifer K Lee
- Department of Anesthesiology and Critical Care Medicine, Johns Hopkins University, Baltimore, Maryland, USA.,Pathobiology Graduate Training Program, Johns Hopkins University, Baltimore, Maryland, USA
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Spatial T-maze identifies cognitive deficits in piglets 1 month after hypoxia-ischemia in a model of hippocampal pyramidal neuron loss and interneuron attrition. Behav Brain Res 2019; 369:111921. [PMID: 31009645 DOI: 10.1016/j.bbr.2019.111921] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2018] [Revised: 04/02/2019] [Accepted: 04/19/2019] [Indexed: 12/19/2022]
Abstract
Neonatal brain injury from hypoxia-ischemia (HI) causes major morbidity. Piglet HI is an established method for testing neuroprotective treatments in large, gyrencephalic brain. Though many neurobehavior tests exist for rodents, such tests and their associations with neuropathologic injury remain underdeveloped and underutilized in large, neonatal HI animal models. We examined whether spatial T-maze and inclined beam tests distinguish cognitive and motor differences between HI and sham piglets and correlate with neuropathologic injury. Neonatal piglets were randomized to whole-body HI or sham procedure, and they began T-maze and inclined beam testing 17 days later. HI piglets had more incorrect T-maze turns than did shams. Beam walking time did not differ between groups. Neuropathologic evaluations at 33 days validated the injury with putamen neuron loss after HI to below that of sham procedure. HI decreased the numbers of CA3 pyramidal neurons but not CA1 pyramidal neurons or dentate gyrus granule neurons. Though the number of hippocampal parvalbumin-positive interneurons did not differ between groups, HI reduced the number of CA1 interneuron dendrites. Piglets with more incorrect turns had greater CA3 neuron loss, and piglets that took longer in the maze had fewer CA3 interneurons. The number of putamen neurons was unrelated to T-maze or beam performance. We conclude that neonatal HI causes hippocampal CA3 neuron loss, CA1 interneuron dendritic attrition, and putamen neuron loss at 1-month recovery. The spatial T-maze identifies learning and memory deficits that are related to loss of CA3 pyramidal neurons and fewer parvalbumin-positive interneurons independent of putamen injury.
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22
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Ponnusamy V, Yip PK. The role of microRNAs in newborn brain development and hypoxic ischaemic encephalopathy. Neuropharmacology 2019; 149:55-65. [PMID: 30716413 DOI: 10.1016/j.neuropharm.2018.11.041] [Citation(s) in RCA: 34] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2018] [Revised: 11/28/2018] [Accepted: 11/30/2018] [Indexed: 02/08/2023]
Abstract
Neonates can develop hypoxic-ischaemic encephalopathy (HIE) due to lack of blood supply or oxygen, resulting in a major cause of death and disability among term newborns. However, current definitive treatment of therapeutic hypothermia, will only benefit one out of nine babies. Furthermore, the mechanisms of HIE and therapeutic hypothermia are not fully understood. Recently, microRNAs (miRNAs) have become of interest to many researchers due to their important role in post-transcriptional control and deep evolutionary history. Despite this, role of miRNAs in newborns with HIE remains largely unknown due to limited research in this field. Therefore, this review aims to understand the role of miRNAs in normal brain development and HIE pathophysiology with reliance on extrapolated data from other diseases, ages and species due to current limited data. This will provide us with an overview of how miRNAs in normal brain development changes after HIE. Furthermore, it will indicate how miRNAs are affected specifically or globally by the various pathophysiological events. In addition, we discuss about how drugs and commercially available agents can specifically target certain miRNAs as a mechanism of action and potential safety issue with off-target effects. Improving our understanding of the role of miRNAs on the cellular response after HIE would enhance the success of effective diagnosis, prognosis, and treatment of newborns with HIE.
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Affiliation(s)
- Vennila Ponnusamy
- Centre of Genomics and Child Health, Blizard Institute, Barts and London School of Medicine and Dentistry, Queen Mary University of London, UK; Neonatal Intensive Care Unit, Ashford and St. Peter's Hospitals NHS Trust, Chertsey, UK.
| | - Ping K Yip
- Center of Neuroscience, Surgery and Trauma, Blizard Institute, Barts and London School of Medicine and Dentistry, Queen Mary University of London, UK.
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23
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Koehler RC, Yang ZJ, Lee JK, Martin LJ. Perinatal hypoxic-ischemic brain injury in large animal models: Relevance to human neonatal encephalopathy. J Cereb Blood Flow Metab 2018; 38:2092-2111. [PMID: 30149778 PMCID: PMC6282216 DOI: 10.1177/0271678x18797328] [Citation(s) in RCA: 47] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Perinatal hypoxia-ischemia resulting in death or lifelong disabilities remains a major clinical disorder. Neonatal models of hypoxia-ischemia in rodents have enhanced our understanding of cellular mechanisms of neural injury in developing brain, but have limitations in simulating the range, accuracy, and physiology of clinical hypoxia-ischemia and the relevant systems neuropathology that contribute to the human brain injury pattern. Large animal models of perinatal hypoxia-ischemia, such as partial or complete asphyxia at the time of delivery of fetal monkeys, umbilical cord occlusion and cerebral hypoperfusion at different stages of gestation in fetal sheep, and severe hypoxia and hypoperfusion in newborn piglets, have largely overcome these limitations. In monkey, complete asphyxia produces preferential injury to cerebellum and primary sensory nuclei in brainstem and thalamus, whereas partial asphyxia produces preferential injury to somatosensory and motor cortex, basal ganglia, and thalamus. Mid-gestational fetal sheep provide a valuable model for studying vulnerability of progenitor oligodendrocytes. Hypoxia followed by asphyxia in newborn piglets replicates the systems injury seen in term newborns. Efficacy of post-insult hypothermia in animal models led to the success of clinical trials in term human neonates. Large animal models are now being used to explore adjunct therapy to augment hypothermic neuroprotection.
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Affiliation(s)
- Raymond C Koehler
- 1 Department of Anesthesiology and Critical Care Medicine, Johns Hopkins University, Baltimore, MD, USA
| | - Zeng-Jin Yang
- 1 Department of Anesthesiology and Critical Care Medicine, Johns Hopkins University, Baltimore, MD, USA
| | - Jennifer K Lee
- 1 Department of Anesthesiology and Critical Care Medicine, Johns Hopkins University, Baltimore, MD, USA.,2 The Pathobiology Graduate Training Program, Johns Hopkins University, Baltimore, MD, USA
| | - Lee J Martin
- 2 The Pathobiology Graduate Training Program, Johns Hopkins University, Baltimore, MD, USA.,3 Department of Pathology, Division of Neuropathology, Johns Hopkins University, Baltimore, MD, USA
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24
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Hsieh YS, Kwon S, Lee HS, Seol GH. Linalyl acetate prevents hypertension-related ischemic injury. PLoS One 2018; 13:e0198082. [PMID: 29799836 PMCID: PMC5969747 DOI: 10.1371/journal.pone.0198082] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2017] [Accepted: 05/14/2018] [Indexed: 01/01/2023] Open
Abstract
Ischemic stroke remains an important cause of disability and mortality. Hypertension is a critical risk factor for the development of ischemic stroke. Control of risk factors, including hypertension, is therefore important for the prevention of ischemic stroke. Linalyl acetate (LA) has been reported to have therapeutic effects in ischemic stroke by modulating intracellular Ca2+ concentration and having anti-oxidative properties. The preventive efficacy of LA has not yet been determined. This study therefore investigated the preventive efficacy of LA in rat aortas exposed to hypertension related-ischemic injury, and the mechanism of action of LA.Hypertension was induced in vivo following ischemic injury to the aorta induced by oxygen-glucose deprivation and reoxygenation in vitro. Effects of LA were assayed by western blotting, by determining concentrations of lactate dehydrogenase (LDH) and reactive oxygen species (ROS) and by vascular contractility assays. LA significantly reduced systolic blood pressure in vivo. In vitro, LA suppressed ischemic injury-induced expression of the nicotinamide adenine dinucleotide phosphate (NADPH) oxidase subunit p47phox, as well as ROS production, LDH release, and ROS-induced endothelial nitric oxide synthase suppression. These findings indicate that LA has anti-hypertensive properties that can prevent hypertension-related ischemic injury and can prevent NADPH oxidase-induced production of ROS.
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Affiliation(s)
- Yu Shan Hsieh
- Department of Basic Nursing Science, School of Nursing, Korea University, Seoul, Republic of Korea
| | - Soonho Kwon
- Department of Basic Nursing Science, School of Nursing, Korea University, Seoul, Republic of Korea
| | - Hui Su Lee
- Department of Basic Nursing Science, School of Nursing, Korea University, Seoul, Republic of Korea
| | - Geun Hee Seol
- Department of Basic Nursing Science, School of Nursing, Korea University, Seoul, Republic of Korea
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25
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Wassink G, Davidson JO, Lear CA, Juul SE, Northington F, Bennet L, Gunn AJ. A working model for hypothermic neuroprotection. J Physiol 2018; 596:5641-5654. [PMID: 29660115 DOI: 10.1113/jp274928] [Citation(s) in RCA: 57] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2017] [Accepted: 03/28/2018] [Indexed: 01/04/2023] Open
Abstract
Therapeutic hypothermia significantly improves survival without disability in near-term and full-term newborns with moderate to severe hypoxic-ischaemic encephalopathy. However, hypothermic neuroprotection is incomplete. The challenge now is to find ways to further improve outcomes. One major limitation to progress is that the specific mechanisms of hypothermia are only partly understood. Evidence supports the concept that therapeutic cooling suppresses multiple extracellular death signals, including intracellular pathways of apoptotic and necrotic cell death and inappropriate microglial activation. Thus, the optimal depth of induced hypothermia is that which effectively suppresses the cell death pathways after hypoxia-ischaemia, but without inhibiting recovery of the cellular environment. Thus mild hypothermia needs to be continued until the cell environment has recovered until it can actively support cell survival. This review highlights that key survival cues likely include the inter-related restoration of neuronal activity and growth factor release. This working model suggests that interventions that target overlapping mechanisms, such as anticonvulsants, are unlikely to materially augment hypothermic neuroprotection. We suggest that further improvements are most likely to be achieved with late interventions that maximise restoration of the normal cell environment after therapeutic hypothermia, such as recombinant human erythropoietin or stem cell therapy.
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Affiliation(s)
- Guido Wassink
- Department of Physiology, University of Auckland, Auckland, New Zealand
| | - Joanne O Davidson
- Department of Physiology, University of Auckland, Auckland, New Zealand
| | | | - Sandra E Juul
- Department of Pediatrics, University of Washington, Seattle, WA, USA
| | - Frances Northington
- Department of Pediatrics, Johns Hopkins School of Medicine, Baltimore, MD, USA
| | - Laura Bennet
- Department of Physiology, University of Auckland, Auckland, New Zealand
| | - Alistair J Gunn
- Department of Physiology, University of Auckland, Auckland, New Zealand
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26
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Dogan Z, Elbe H, Taslidere E, Soysal H, Cetin A, Demirtas S. Effects of ciprofloxacin on fetal rat liver during pregnancy and protective effects of quercetin. Biotech Histochem 2017; 92:481-486. [PMID: 28836867 DOI: 10.1080/10520295.2017.1356469] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
Urinary tract infections are common in pregnant women and ciprofloxacin frequently is used as a broad spectrum antibiotic. It has been suggested that ciprofloxacin causes liver damage in fetuses. Quercetin is a flavonoid with antioxidant properties. We investigated the efficacy of quercetin treatment for preventing fetal liver damage caused by ciprofloxacin. Pregnant rats were divided into four groups: untreated control group (C), 20 mg/kg quercetin for 21 days group (Q), 20 mg/kg twice/day ciprofloxacin for 10 days group (CP), and 20 mg/kg, ciprofloxacin + quercetin for 21 days group (CP + Q). Fetal livers were removed on day 21 of gestation to measure antioxidants and for histological observation. Malondialdehyde (MDA) and glutathione (GSH) levels, and superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GSH-Px) activities were measured in tissue samples. GSH-Px, SOD and CAT activities were significantly lower in the CP group compared to group C. A significant increase in MDA was observed in the CP group compared to group C. There was no significant difference in GSH levels in any group. MDA levels were lower and CAT, SOD and GSH-Px enzyme activities were higher in the CP + Q group compared to group CP. Liver samples of the CP group exhibited central vein dilation, portal vein congestion, pyknotic nuclei and cytoplasmic vacuolization in some hepatocytes. Histological changes were less prominent in the rats treated with quercetin. Use of ciprofloxacin during pregnancy caused oxidative damage in fetal liver tissue. Oxidative stress was ameliorated by quercetin. Quercetin supports the antioxidant defense mechanism and it is beneficial for treating fetal liver damage caused by ciprofloxacin.
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Affiliation(s)
- Z Dogan
- a Department of Anatomy, Faculty of Medicine , Adiyaman University , Adiyaman
| | - H Elbe
- b Department of Histology and Embryology, Faculty of Medicine , Mugla Sıtkı Kocman University , Mugla
| | - E Taslidere
- c Department of Histology and Embryology, Faculty of Medicine , Bezmialem Vakif University , Istanbul
| | - H Soysal
- d Department of Anatomy, Faculty of Medicine , Baskent University , Ankara
| | | | - S Demirtas
- f Biochemistry , Inonu University, Faculty of Medicine , Malatya , Turkey
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Impaired autophagosome clearance contributes to neuronal death in a piglet model of neonatal hypoxic-ischemic encephalopathy. Cell Death Dis 2017; 8:e2919. [PMID: 28703794 DOI: 10.1038/cddis.2017.318] [Citation(s) in RCA: 45] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2017] [Revised: 05/29/2017] [Accepted: 06/07/2017] [Indexed: 01/21/2023]
Abstract
To examine the temporal relationship of cortical autophagic flux with delayed neuronal cell death after hypoxia-ischemia (HI) in neonatal piglets. HI was produced with 45-min hypoxia and 7-min airway occlusion in 3-5-day-old piglets. Markers of autophagic, lysosomal and cell death signaling were studied via immunohistochemistry, immunoblotting, and histochemistry in piglet brains. In vitro, autophagy was impaired in cultured mouse cortical neurons treated with chloroquine with or without rapamycin for 1 d in the presence of Z-VAD-fmk, cyclosporine A, or vehicle control, and cell viability was assessed with the MTT assay. In vivo, neuronal cell death of sensorimotor cortex was delayed by 1-2 days after HI, whereas LC3-II, Beclin-1, PI3KC3, ATG12-ATG-5, and p-ULK1 increased by 1.5-6 h. Autophagosomes accumulated in cortical neurons by 1 d owing to enhanced autophagy and later to decreased autophagosome clearance, as indicated by LC3, Beclin-1, and p62 accumulation. Autophagy flux impairment was attributable to lysosomal dysfunction, as indicated by low lysosomal-associated membrane protein 2, cathepsin B, and cathepsin D levels at 1 d. Ubiquitin levels increased at 1 d. Autophagosome and p62 accumulated predominantly in neurons at 1 d, with p62 puncta occurring in affected cells. Beclin-1 colocalized with markers of caspase-dependent and caspase-independent apoptosis and necrosis in neurons. In vitro, mouse neonatal cortical neurons treated with rapamycin and chloroquine showed increased autophagosomes, but not autolysosomes, and increased cell death that was attenuated by cyclosporine A. Neonatal HI initially increases autophagy but later impairs autophagosome clearance, coinciding with delayed cortical neuronal death.
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28
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Ramdial K, Franco MC, Estevez AG. Cellular mechanisms of peroxynitrite-induced neuronal death. Brain Res Bull 2017; 133:4-11. [DOI: 10.1016/j.brainresbull.2017.05.008] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2016] [Revised: 04/21/2017] [Accepted: 05/12/2017] [Indexed: 12/13/2022]
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Netto CA, Sanches E, Odorcyk FK, Duran-Carabali LE, Weis SN. Sex-dependent consequences of neonatal brain hypoxia-ischemia in the rat. J Neurosci Res 2016; 95:409-421. [DOI: 10.1002/jnr.23828] [Citation(s) in RCA: 59] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2016] [Revised: 06/14/2016] [Accepted: 06/20/2016] [Indexed: 12/25/2022]
Affiliation(s)
- Carlos Alexandre Netto
- Department of Biochemistry, Instituto de Ciências Básicas da Saúde; Universidade Federal do Rio Grande do Sul; Porto Alegre Rio Grande do Sul Brazil
| | - Eduardo Sanches
- Division of Child Development and Growth, Department of Pediatrics; University of Geneva; Geneva Switzerland
| | - Felipe Kawa Odorcyk
- Postgraduate Program of Neurosciences, Instituto de Ciências Básicas da Saúde; Universidade Federal do Rio Grande do Sul; Porto Alegre Rio Grande do Sul Brazil
| | - Luz Elena Duran-Carabali
- Postgraduate Program of Physiology, Instituto de Ciências Básicas da Saúde; Universidade Federal do Rio Grande do Sul; Porto Alegre Rio Grande do Sul Brazil
| | - Simone Nardin Weis
- Department of Cellular Biology; Universidade de Brasília; Brasilia Distrito Federal Brazil
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Short-term effects of cannabidiol after global hypoxia-ischemia in newborn piglets. Pediatr Res 2016; 80:710-718. [PMID: 27441365 DOI: 10.1038/pr.2016.149] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/07/2016] [Accepted: 05/15/2016] [Indexed: 12/21/2022]
Abstract
BACKGROUND Cannabidiol (CBD), a nonpsychoactive cannabinoid, has shown neuroprotective actions after neonatal hypoxia-ischemia (HI) in animals. We wanted to further explore the effects of CBD, alone and in conjunction with hypothermia, in a piglet model of global HI. METHODS Fifty-five anesthetized newborn piglets were randomized to either controls (n = 7) or HI (n = 48) by ventilation with 8% O2 until mean arterial blood pressure reached 20 mmHg and/or base excess reached -20 mmol/l. After resuscitation piglets were randomized to either: vehicle (VEH), CBD 1mg/kg, VEH+hypothermia (H) or CBD 1mg/kg+H (each n = 12). Piglets were euthanized 9.5 h after HI and plasma, urine, cerebrospinal fluid, and brain tissue were sampled for analysis. RESULTS HI induced global damage with significantly increased neuropathology score, S100B in cerebrospinal fluid, hippocampal proton magnetic resonance spectroscopy biomarkers, plasma troponin-T, and urinary neutrophil gelatinase-associated lipocalin. CBD alone did not have any significant effects on these parameters while CBD+H reduced urinary neutrophil gelatinase-associated lipocalin compared with VEH+H (P < 0.05). Both hypothermic groups had significantly lower glutamate/N-acetylaspartate ratios (P < 0.01) and plasma troponin-T (P<0.05) levels compared with normothermic groups. CONCLUSION In contrast to previous studies, we do not find significant protective effects of CBD after HI in piglets. Evaluation of CBD in higher doses might be warranted.
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Lee JK, Wang B, Reyes M, Armstrong JS, Kulikowicz E, Santos PT, Lee JH, Koehler RC, Martin LJ. Hypothermia and Rewarming Activate a Macroglial Unfolded Protein Response Independent of Hypoxic-Ischemic Brain Injury in Neonatal Piglets. Dev Neurosci 2016; 38:277-294. [PMID: 27622292 DOI: 10.1159/000448585] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2016] [Accepted: 07/20/2016] [Indexed: 12/22/2022] Open
Abstract
Therapeutic hypothermia provides incomplete neuroprotection after hypoxia-ischemia (HI)-induced brain injury in neonates. We previously showed that cortical neuron and white matter apoptosis are promoted by hypothermia and early rewarming in a piglet model of HI. The unfolded protein response (UPR) may be one of the potential mediators of this cell death. Here, neonatal piglets underwent HI or sham surgery followed by 29 h of normothermia, 2 h of normothermia + 27 h of hypothermia or 18 h of hypothermia + rewarming. Piglets recovered for 29 h. Immunohistochemistry for endoplasmic reticulum to nucleus signaling-1 protein (ERN1), a marker of UPR activation, was used to determine the ratios of ERN1+ macroglia and neurons in the motor subcortical white matter and cerebral cortex. The ERN1+ macroglia were immunophenotyped as oligodendrocytes and astrocytes by immunofluorescent colabeling. Temperature (p = 0.046) and HI (p < 0.001) independently affected the ratio of ERN1+ macroglia. In sham piglets, sustained hypothermia (p = 0.011) and rewarming (p = 0.004) increased the ERN1+ macroglia ratio above that in normothermia. HI prior to hypothermia diminished the UPR. Ratios of ERN1+ macroglia correlated with white matter apoptotic profile counts in shams (r = 0.472; p = 0.026), thereby associating UPR activation with white matter apoptosis during hypothermia and rewarming. Accordingly, macroglial cell counts decreased in shams that received sustained hypothermia (p = 0.009) or rewarming (p = 0.007) compared to those in normothermic shams. HI prior to hypothermia neutralized the macroglial cell loss. Neither HI nor temperature affected ERN1+ neuron ratios. In summary, delayed hypothermia and rewarming activate the macroglial UPR, which is associated with white matter apoptosis. HI may decrease the macroglial endoplasmic reticulum stress response after hypothermia and rewarming.
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Affiliation(s)
- Jennifer K Lee
- Department of Anesthesiology and Critical Care Medicine, Johns Hopkins University, Baltimore, Md., USA
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32
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The role of Golgi reassembly and stacking protein 65 phosphorylation in H2O2-induced cell death and Golgi morphological changes. Med Mol Morphol 2016; 49:217-223. [DOI: 10.1007/s00795-016-0138-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2015] [Accepted: 02/15/2016] [Indexed: 11/25/2022]
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33
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Kletkiewicz H, Nowakowska A, Siejka A, Mila-Kierzenkowska C, Woźniak A, Caputa M, Rogalska J. Deferoxamine prevents cerebral glutathione and vitamin E depletions in asphyxiated neonatal rats: role of body temperature. Int J Hyperthermia 2016; 32:211-20. [PMID: 26794834 DOI: 10.3109/02656736.2015.1125955] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Hypoxic-ischaemic brain injury involves increased oxidative stress. In asphyxiated newborns iron deposited in the brain catalyses formation of reactive oxygen species. Glutathione (GSH) and vitamin E are key factors protecting cells against such agents. Our previous investigation has demonstrated that newborn rats, showing physiological low body temperature as well as their hyperthermic counterparts injected with deferoxamine (DF) are protected against iron-mediated, delayed neurotoxicity of perinatal asphyxia. Therefore, we decided to study the effects of body temperature and DF on the antioxidant status of the brain in rats exposed neonatally to critical anoxia. Two-day-old newborn rats were exposed to anoxia in 100% nitrogen atmosphere for 10 min. Rectal temperature was kept at 33 °C (physiological to rat neonates), or elevated to the level typical of healthy adult rats (37 °C), or of febrile adult rats (39 °C). Half of the rats exposed to anoxia under extremely hyperthermic conditions (39 °C) were injected with DF. Cerebral concentrations of malondialdehyde (MDA, lipid peroxidation marker) and the levels of GSH and vitamin E were determined post-mortem, (1) immediately after anoxia, (2) 3 days, (3) 7 days, and (4) 2 weeks after anoxia. There were no post-anoxic changes in MDA, GSH and vitamin E concentrations in newborn rats kept at body temperature of 33 °C. In contrast, perinatal anoxia at elevated body temperatures intensified oxidative stress and depleted the antioxidant pool in a temperature-dependent manner. Both the depletion of antioxidants and lipid peroxidation were prevented by post-anoxic DF injection. The data support the idea that hyperthermia may extend perinatal anoxia-induced brain lesions.
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Affiliation(s)
- Hanna Kletkiewicz
- a N. Copernicus University , Department of Animal Physiology, Faculty of Biology and Environmental Protection , Toruń , Poland and
| | - Anna Nowakowska
- a N. Copernicus University , Department of Animal Physiology, Faculty of Biology and Environmental Protection , Toruń , Poland and
| | - Agnieszka Siejka
- a N. Copernicus University , Department of Animal Physiology, Faculty of Biology and Environmental Protection , Toruń , Poland and
| | | | - Alina Woźniak
- b N. Copernicus University , Department of Medical Biology, Collegium Medicum , Bydgoszcz , Poland
| | - Michał Caputa
- a N. Copernicus University , Department of Animal Physiology, Faculty of Biology and Environmental Protection , Toruń , Poland and
| | - Justyna Rogalska
- a N. Copernicus University , Department of Animal Physiology, Faculty of Biology and Environmental Protection , Toruń , Poland and
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Chavez-Valdez R, Flock DL, Martin LJ, Northington FJ. Endoplasmic reticulum pathology and stress response in neurons precede programmed necrosis after neonatal hypoxia-ischemia. Int J Dev Neurosci 2015; 48:58-70. [PMID: 26643212 DOI: 10.1016/j.ijdevneu.2015.11.007] [Citation(s) in RCA: 49] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2015] [Revised: 11/24/2015] [Accepted: 11/24/2015] [Indexed: 11/26/2022] Open
Abstract
The endoplasmic reticulum (ER) is tasked, among many other functions, with preventing excitotoxicity from killing neurons following neonatal hypoxia-ischemia (HI). With the search for delayed therapies to treat neonatal HI, the study of delayed ER responses becomes relevant. We hypothesized that ER stress is a prominent feature of delayed neuronal death via programmed necrosis after neonatal HI. Since necrostatin-1 (Nec-1), an inhibitor of programmed necrosis, provides delayed neuroprotection against neonatal HI in male mice, Nec-1 is an ideal tool to study delayed ER responses. C57B6 male mice were exposed to right carotid ligation followed by exposure to FiO2=0.08 for 45 min at p7. Mice were treated with vehicle or Nec-1 (0.1 μl of 8 μmol) intracerebroventricularly with age-matched littermates as controls. Biochemistry assays at 3 and 24h and electron microscopy (EM) and immunohistochemistry at 96 h after HI were performed. EM showed ER dilation and mitochondrial swelling as apparent early changes in neurons. With advanced neurodegeneration, large cytoplasmic fragments containing dilated ER "shed" into the surrounding neuropil and calreticulin immunoreactivity was lost concurrent with nuclear features suggestive of programmed necrosis. Nec-1 attenuated biochemical markers of ER stress after neonatal HI, including PERK and eIF2α phosphorylation, and unconventional XBP-1 splicing, consistent with the mitigation of later ER pathology. ER pathology may be an indicator of severity of neuronal injury and potential for recovery characterized by cytoplasmic shedding, distinct from apoptotic blebbing, that we term neuronal macrozeiosis. Therapies to attenuate ER stress applied at delayed stages may rescue stressed neurons after neonatal HI.
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Affiliation(s)
- Raul Chavez-Valdez
- Department of Pediatrics, Neonatal Research Laboratory, Johns Hopkins University School of Medicine, 600 N. Wolfe Street, CMSC 6-104, Baltimore, MD 21287, USA.
| | - Debbie L Flock
- Department of Pediatrics, Neonatal Research Laboratory, Johns Hopkins University School of Medicine, 600 N. Wolfe Street, CMSC 6-104, Baltimore, MD 21287, USA.
| | - Lee J Martin
- Departments of Pathology and Neuroscience, Johns Hopkins University School of Medicine, 720 Rutland Ave. Ross Research Building, Room 558, Baltimore, MD 21205, USA.
| | - Frances J Northington
- Department of Pediatrics, Neonatal Research Laboratory, Johns Hopkins University School of Medicine, 600 N. Wolfe Street, CMSC 6-104, Baltimore, MD 21287, USA.
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Marcelino TB, de Lemos Rodrigues PI, Miguel PM, Netto CA, Pereira Silva LO, Matté C. Effect of maternal exercise on biochemical parameters in rats submitted to neonatal hypoxia-ischemia. Brain Res 2015; 1622:91-101. [DOI: 10.1016/j.brainres.2015.06.024] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2015] [Revised: 06/17/2015] [Accepted: 06/18/2015] [Indexed: 01/25/2023]
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Lu Q, Harris VA, Rafikov R, Sun X, Kumar S, Black SM. Nitric oxide induces hypoxia ischemic injury in the neonatal brain via the disruption of neuronal iron metabolism. Redox Biol 2015. [PMID: 26209813 PMCID: PMC4804102 DOI: 10.1016/j.redox.2015.06.007] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
We have recently shown that increased hydrogen peroxide (H2O2) generation is involved in hypoxia–ischemia (HI)-mediated neonatal brain injury. H2O2 can react with free iron to form the hydroxyl radical, through Fenton Chemistry. Thus, the objective of this study was to determine if there was a role for the hydroxyl radical in neonatal HI brain injury and to elucidate the underlying mechanisms. Our data demonstrate that HI increases the deposition of free iron and hydroxyl radical formation, in both P7 hippocampal slice cultures exposed to oxygen–glucose deprivation (OGD), and the neonatal rat exposed to HI. Both these processes were found to be nitric oxide (NO) dependent. Further analysis demonstrated that the NO-dependent increase in iron deposition was mediated through increased transferrin receptor expression and a decrease in ferritin expression. This was correlated with a reduction in aconitase activity. Both NO inhibition and iron scavenging, using deferoxamine administration, reduced hydroxyl radical levels and neuronal cell death. In conclusion, our results suggest that increased NO generation leads to neuronal cell death during neonatal HI, at least in part, by altering iron homeostasis and hydroxyl radical generation. HI increases the deposition of free iron and hydroxyl radical formation in the neonatal brain. Both these processes are NO dependent. Increased iron deposition is mediated via increased TfR and decreased ferritin expression. These processes are involved in the neuronal cell death associated with neonatal HI.
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Affiliation(s)
- Qing Lu
- Department of Neuroscience and Regenerative Medicine, Georgia Regents University, Augusta, GA 30912, USA
| | - Valerie A Harris
- Vascular Biology Center, Georgia Regents University, Augusta, GA 30912, USA
| | - Ruslan Rafikov
- Division of Translational and Regenerative Medicine, Department of Medicine, University of Arizona, Tucson, AZ 85724, USA
| | - Xutong Sun
- Division of Translational and Regenerative Medicine, Department of Medicine, University of Arizona, Tucson, AZ 85724, USA
| | - Sanjiv Kumar
- Vascular Biology Center, Georgia Regents University, Augusta, GA 30912, USA
| | - Stephen M Black
- Division of Translational and Regenerative Medicine, Department of Medicine, University of Arizona, Tucson, AZ 85724, USA.
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Rewarming from therapeutic hypothermia induces cortical neuron apoptosis in a swine model of neonatal hypoxic-ischemic encephalopathy. J Cereb Blood Flow Metab 2015; 35:781-93. [PMID: 25564240 PMCID: PMC4420851 DOI: 10.1038/jcbfm.2014.245] [Citation(s) in RCA: 54] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/25/2014] [Revised: 12/05/2014] [Accepted: 12/08/2014] [Indexed: 11/08/2022]
Abstract
The consequences of therapeutic hypothermia for neonatal hypoxic-ischemic encephalopathy are poorly understood. Adverse effects from suboptimal rewarming could diminish neuroprotection from hypothermia. Therefore, we tested whether rewarming is associated with apoptosis. Piglets underwent hypoxia-asphyxia followed by normothermic or hypothermic recovery at 2 hours. Hypothermic groups were divided into those with no rewarming, rewarming at 0.5 °C/hour, or rewarming at 4 °C/hour. Neurodegeneration at 29 hours was assessed by hematoxylin and eosin staining, TUNEL assay, and immunoblotting for cleaved caspase-3. Rewarmed piglets had more apoptosis in motor cortex than did those that remained hypothermic after hypoxia-asphyxia. Apoptosis in piriform cortex was greater in hypoxic-asphyxic, rewarmed piglets than in naive/sham piglets. Caspase-3 inhibitor suppressed apoptosis with rewarming. Rapidly rewarmed piglets had more caspase-3 cleavage in cerebral cortex than did piglets that remained hypothermic or piglets that were rewarmed slowly. We conclude that rewarming from therapeutic hypothermia can adversely affect the newborn brain by inducing apoptosis through caspase mechanisms.
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Zhu J, Wang B, Lee JH, Armstrong JS, Kulikowicz E, Bhalala US, Martin LJ, Koehler RC, Yang ZJ. Additive Neuroprotection of a 20-HETE Inhibitor with Delayed Therapeutic Hypothermia after Hypoxia-Ischemia in Neonatal Piglets. Dev Neurosci 2015; 37:376-89. [PMID: 25721266 DOI: 10.1159/000369007] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2014] [Accepted: 10/10/2014] [Indexed: 12/28/2022] Open
Abstract
The severity of perinatal hypoxia-ischemia and the delay in initiating therapeutic hypothermia limit the efficacy of hypothermia. After hypoxia-ischemia in neonatal piglets, the arachidonic acid metabolite 20-hydroxyeicosatetraenoic acid (20-HETE) has been found to contribute to oxidative stress at 3 h of reoxygenation and to eventual neurodegeneration. We tested whether early administration of a 20-HETE synthesis inhibitor after reoxygenation augments neuroprotection with 3-hour delayed hypothermia. In two hypothermic groups, whole body cooling from 38.5 to 34°C was initiated 3 h after hypoxia-ischemia. Rewarming occurred from 20 to 24 h; then anesthesia was discontinued. One hypothermic group received a 20-HETE inhibitor at 5 min after reoxygenation. A sham-operated group and another hypoxia-ischemia group remained normothermic. At 10 days of recovery, resuscitated piglets with delayed hypothermia alone had significantly greater viable neuronal density in the putamen, caudate nucleus, sensorimotor cortex, CA3 hippocampus, and thalamus than did piglets with normothermic recovery, but the values remained less than those in the sham-operated group. In piglets administered the 20-HETE inhibitor before hypothermia, the density of viable neurons in the putamen, cortex and thalamus was significantly greater than in the group with hypothermia alone. Cytochrome P450 4A, which can synthesize 20-HETE, was expressed in piglet neurons in these regions. We conclude that early treatment with a 20-HETE inhibitor enhances the therapeutic benefit of delayed hypothermia in protecting neurons in brain regions known to be particularly vulnerable to hypoxia-ischemia in term newborns.
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Affiliation(s)
- Junchao Zhu
- Department of Anesthesiology and Critical Care Medicine, Johns Hopkins University, Baltimore, Md, USA
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Hoque N, Sabir H, Maes E, Bishop S, Thoresen M. Validation of a neuropathology score using quantitative methods to evaluate brain injury in a pig model of hypoxia ischaemia. J Neurosci Methods 2014; 230:30-6. [PMID: 24747875 DOI: 10.1016/j.jneumeth.2014.04.005] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2014] [Revised: 03/30/2014] [Accepted: 04/05/2014] [Indexed: 01/20/2023]
Abstract
BACKGROUND Neuropathological examination is the classic outcome measure in experimental studies of newborn brain injury to evaluate novel therapies. We have used a graded neuropathology score in an established global model of perinatal hypoxic-ischaemic (HI) injury. We wished to validate the score using cell counting in our model. NEW METHOD 32 newborn pigs underwent a 45 min global HI insult then maintained at normothermia (NT, rectal temperature, Trectal 38.5 °C) for 72 h or mild total body hypothermia (HT, Trectal 37.0 °C) combined with selective head cooling for 48 h and subsequently maintained at NT for 24h before brain perfusion fixation. A perinatal pathologist scored haematoxylin and eosin stained 6 μm histological sections for injury in the hippocampus and basal ganglia on a 9-step scale (0.0=no injury, 4.0=>75% injury). We counted the number of healthy neurons in the hippocampus CA1 region and putamen using morphological criteria in eight random, non-overlapping fields from representative sections. RESULTS Healthy neuronal cell density correlated with neuropathology score in the hippocampus CA1 (r = -0.74) and in the putamen (r = -0.75) and both measures detected a difference between groups. The correlation coefficients were better for the NT compared to the HT group in both the hippocampus (r = -0.87 vs. -0.53) and putamen (r = -0.77 vs. -0.54). COMPARISON WITH EXISTING METHOD We have validated a histological neuropathological scoring system in our model of perinatal HI by showing correlation between neuronal cell count and estimated injury. CONCLUSIONS Our neuropathology score is a valid method to assess brain injury with good reproducibility and sensitivity.
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Affiliation(s)
- Nicholas Hoque
- Neonatal Neuroscience, School of Clinical Sciences, University of Bristol, St Michael's Hospital, Southwell Street, Bristol, Avon BS2 8EG, United Kingdom
| | - Hemmen Sabir
- Neonatal Neuroscience, School of Clinical Sciences, University of Bristol, St Michael's Hospital, Southwell Street, Bristol, Avon BS2 8EG, United Kingdom
| | - Elke Maes
- Neonatal Neuroscience, School of Clinical Sciences, University of Bristol, St Michael's Hospital, Southwell Street, Bristol, Avon BS2 8EG, United Kingdom; Department of Physiology, Institute of Basic Medical Sciences, University of Oslo, Postboks 1103, Blindern, 0317 Oslo, Norway
| | - Sarah Bishop
- Neonatal Neuroscience, School of Clinical Sciences, University of Bristol, St Michael's Hospital, Southwell Street, Bristol, Avon BS2 8EG, United Kingdom
| | - Marianne Thoresen
- Neonatal Neuroscience, School of Clinical Sciences, University of Bristol, St Michael's Hospital, Southwell Street, Bristol, Avon BS2 8EG, United Kingdom; Department of Physiology, Institute of Basic Medical Sciences, University of Oslo, Postboks 1103, Blindern, 0317 Oslo, Norway.
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Ji G, Ji H, Mo X, Li T, Yu Y, Hu Z. The role of GRASPs in morphological alterations of Golgi apparatus: mechanisms and effects. Rev Neurosci 2014; 24:485-97. [PMID: 24002661 DOI: 10.1515/revneuro-2013-0020] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2013] [Accepted: 08/10/2013] [Indexed: 11/15/2022]
Abstract
The Golgi apparatus (GA) is a pivotal organelle in cell metabolism, functioning not only in the processing and transportation of cargoes but also in ion homeostasis, cell apoptosis, and stress sensing. We are interested in the intricate role of GA and the recently present novel concept of 'GA stress'. GA shows various morphological alterations in many neurodegenerative diseases and cell apoptosis induced by biochemical reagents, mechanisms in which oxidative stress is strongly involved. In turn, the structural changes and morphological alterations of the GA could also transduce stress signals. Therefore, besides the biochemical changes, more attention should be paid to the morphological alterations of the GA itself during pathological processes and diseases. The Golgi reassembly and stacking proteins (GRASPs) have been identified as important components acting in the transformation of Golgi structure, and they may thus affect the Golgi functions and cell behavior. In this review, we will discuss the intricate role of the GRASPs in remodeling the GA morphology and focus on their mechanisms and effects in the processes of Golgi stacking, mitosis, cell apoptosis, and cargo secretion. We would also like to provide a further prospective of their potential biological values in neurodegenerative diseases.
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The olfactory bulb in newborn piglet is a reservoir of neural stem and progenitor cells. PLoS One 2013; 8:e81105. [PMID: 24278384 PMCID: PMC3836747 DOI: 10.1371/journal.pone.0081105] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2013] [Accepted: 10/14/2013] [Indexed: 12/16/2022] Open
Abstract
The olfactory bulb (OB) periventricular zone is an extension of the forebrain subventricular zone (SVZ) and thus is a source of neuroprogenitor cells and neural stem cells. While considerable information is available on the SVZ-OB neural stem cell (NSC)/neuroprogenitor cell (NPC) niche in rodents, less work has been done on this system in large animals. The newborn piglet is used as a preclinical translational model of neonatal hypoxic-ischemic brain damage, but information about the endogenous sources of NSCs/NPCs in piglet is needed to implement endogenous or autologous cell-based therapies in this model. We characterized NSC/NPC niches in piglet forebrain and OB-SVZ using western blotting, histological, and cell culture methods. Immunoblotting revealed nestin, a NSC/NPC marker, in forebrain-SVZ and OB-SVZ in newborn piglet. Several progenitor or newborn neuron markers, including Dlx2, musashi, doublecortin, and polysialated neural cell adhesion molecule were also detected in OB-SVZ by immunoblotting. Immunohistochemistry confirmed the presence of nestin, musashi, and doublecortin in forebrain-SVZ and OB-SVZ. Bromodeoxyuridine (BrdU) labeling showed that the forebrain-SVZ and OB-SVZ accumulate newly replicated cells. BrdU-positive cells were immunolabeled for astroglial, oligodendroglial, and neuronal markers. A lateral migratory pathway for newly born neuron migration to primary olfactory cortex was revealed by BrdU labeling and co-labeling for doublecortin and class III β tubulin. Isolated and cultured forebrain-SVZ and OB-SVZ cells from newborn piglet had the capacity to generate numerous neurospheres. Single cell clonal analysis of neurospheres revealed the capacity for self-renewal and multipotency. Neurosphere-derived cells differentiated into neurons, astrocytes, and oligodendrocytes and were amenable to permanent genetic tagging with lentivirus encoding green fluorescent protein. We conclude that the piglet OB-SVZ is a reservoir of NSCs and NPCs suitable to use in autologous cell therapy in preclinical models of neonatal/pediatric brain injury.
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Anju T, Paulose C. Striatal cholinergic functional alterations in hypoxic neonatal rats: Role of glucose, oxygen, and epinephrine resuscitation. Biochem Cell Biol 2013; 91:350-6. [DOI: 10.1139/bcb-2012-0102] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
Molecular processes regulating cholinergic functions play an important role in the control of respiration under hypoxia. Cholinergic alterations and its further complications in respiration due to hypoxic insult in neonatal rats and the effect of glucose, oxygen, and epinephrine resuscitation was evaluated in the present study. Receptor binding and gene expression studies were done in the corpus striatum to analyse the changes in total muscarinic receptors, muscarinic M1, M2, M3 receptors, and the enzymes involved in acetylcholine metabolism, choline acetyltransferase and acetylcholinesterase. Neonatal hypoxia decreased total muscarinic receptors with reduced expression of muscarinic M1, M2, and M3 receptor genes. The reduction in acetylcholine metabolism is indicated by the downregulated choline acetyltransferase and upregulated acetyl cholinesterase expression. These cholinergic disturbances were reversed to near control in glucose-resuscitated hypoxic neonates. The adverse effects of immediate oxygenation and epinephrine administration are also reported. The present findings points to the cholinergic alterations due to neonatal hypoxic shock and suggests a proper resuscitation method to ameliorate these striatal changes.
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Affiliation(s)
- T.R. Anju
- Molecular Neurobiology and Cell Biology Unit, Centre for Neuroscience, Department of Biotechnology, Cochin University of Science and Technology, Cochin-682022, Kerala, India
| | - C.S. Paulose
- Molecular Neurobiology and Cell Biology Unit, Centre for Neuroscience, Department of Biotechnology, Cochin University of Science and Technology, Cochin-682022, Kerala, India
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Begum P, Fugetsu B. Induction of cell death by graphene in Arabidopsis thaliana (Columbia ecotype) T87 cell suspensions. JOURNAL OF HAZARDOUS MATERIALS 2013; 260:1032-41. [PMID: 23892171 DOI: 10.1016/j.jhazmat.2013.06.063] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/18/2013] [Revised: 06/21/2013] [Accepted: 06/22/2013] [Indexed: 05/24/2023]
Abstract
The toxicity of graphene on suspensions of Arabidopsis thaliana (Columbia ecotype) T87 cells was investigated by examining the morphology, mitochondrial dysfunction, reactive oxygen species generation (ROS), and translocation of graphene as the toxicological endpoints. The cells were grown in Jouanneau and Péaud-Lenoel (JPL) media and exposed to graphene at concentrations 0-80 mg/L. Morphological changes were observed by scanning electron microscope and the adverse effects such as fragmented nuclei, membrane damage, mitochondrial dysfunction was observed with fluorescence microscopy by staining with Hoechst 33342/propidium iodide and succinate dehydrogenase (mitochondrial bioenergetic enzyme). Analysis of intracellular ROS by 2',7'-dichlorofluorescein diacetate demonstrated that graphene induced a 3.3-fold increase in ROS, suggesting that ROS are key mediators in the cell death signaling pathway. Transmission electron microscopy verified the translocation of graphene into cells and an endocytosis-like structure was observed which suggested graphene entering into the cells by endocytosis. In conclusion, our results show that graphene induced cell death in T87 cells through mitochondrial damage mediated by ROS.
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Affiliation(s)
- Parvin Begum
- Laboratory of Environmental Medical Chemistry, Graduate School of Environmental Science, Hokkaido University, Sapporo 060-0810, Japan.
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Nakamura S, Kusaka T, Yasuda S, Ueno M, Miki T, Koyano K, Nakamura M, Okada H, Okazaki K, Isobe K, Itoh S. Cerebral blood volume combined with amplitude-integrated EEG can be a suitable guide to control hypoxic/ischemic insult in a piglet model. Brain Dev 2013. [PMID: 23199679 DOI: 10.1016/j.braindev.2012.10.007] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
INTRODUCTION The purposes of this study are to compare two hypoxic/ischemic (H/I) insults using amplitude-integrated EEG (aEEG), alone or combined with cerebral blood volume (CBV), as a guide to control hypoxia and to determine which protocol most effectively produces a consistent degree of survivable neuropathological damage in a newborn piglet model of perinatal asphyxia. METHODS Eighteen piglets were subjected to H/I insult of 20-min low aEEG (LAEEG). After the 20-min, the aEEG group was maintained with low mean arterial blood pressure for 10min. The procedure for the aEEG plus CBV group was stopped if CBV became the rated value after 20min of LAEEG. We measured changes in CBV using a near-infrared time-resolved spectroscopy (TRS) and cerebral electrocortical activity using aEEG until 6h post-insult. At 5days post insult, the piglets' brains were perfusion-fixed and stained with hematoxylin/eosin. Piglets were grouped as undamaged or damaged; piglets that did not survive to 5days were grouped separately as dead. RESULTS Among surviving piglets, CBV combined with aEEG resulted in significantly greater percentage of damaged piglets than aEEG alone. CONCLUSIONS We conclude that combining CBV with aEEG may be a more effective guide to control H/I insult in a newborn piglet model than aEEG alone.
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Affiliation(s)
- Shinji Nakamura
- Department of Pediatrics, Faculty of Medicine, Kagawa University, Kagawa, Japan
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Lu Q, Wainwright MS, Harris VA, Aggarwal S, Hou Y, Rau T, Poulsen DJ, Black SM. Increased NADPH oxidase-derived superoxide is involved in the neuronal cell death induced by hypoxia-ischemia in neonatal hippocampal slice cultures. Free Radic Biol Med 2012; 53:1139-51. [PMID: 22728269 PMCID: PMC3527086 DOI: 10.1016/j.freeradbiomed.2012.06.012] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/16/2012] [Revised: 06/07/2012] [Accepted: 06/08/2012] [Indexed: 11/25/2022]
Abstract
Neonatal brain hypoxia-ischemia (HI) results in neuronal cell death. Previous studies indicate that reactive oxygen species, such as superoxide, play a key role in this process. However, the cellular sources have not been established. In this study we examine the role of the nicotinamide adenine dinucleotide phosphate (NADPH) oxidase complex in neonatal HI brain injury and elucidate its mechanism of activation. Rat hippocampal slices were exposed to oxygen glucose deprivation (OGD) to mimic the conditions seen in HI. Initial studies confirmed an important role for NADPH oxidase-derived superoxide in the oxidative stress associated with OGD. Further, the OGD-mediated increase in apoptotic cell death was inhibited by the NADPH oxidase inhibitor apocynin. The activation of NADPH oxidase was found to be dependent on the p38 mitogen-activated protein kinase-mediated phosphorylation and activation of the p47(phox) subunit. Using an adeno-associated virus antisense construct to selectively decrease p47(phox) expression in neurons showed that this led to inhibition of both the increase in superoxide and the neuronal cell death associated with OGD. We also found that NADPH oxidase inhibition in a neonatal rat model of HI or scavenging hydrogen peroxide reduced brain injury. Thus, we conclude that activation of the NADPH oxidase complex contributes to the oxidative stress during HI and that therapies targeted against this complex could provide neuroprotection against the brain injury associated with neonatal HI.
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Affiliation(s)
- Qing Lu
- Vascular Biology Center, Georgia Health Sciences University, Augusta, GA 30912, USA
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Ni X, Yang ZJ, Wang B, Carter EL, Larson AC, Martin LJ, Koehler RC. Early antioxidant treatment and delayed hypothermia after hypoxia-ischemia have no additive neuroprotection in newborn pigs. Anesth Analg 2012; 115:627-37. [PMID: 22745113 DOI: 10.1213/ane.0b013e31825d3600] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
BACKGROUND The implementation and clinical efficacy of hypothermia in neonatal hypoxic-ischemic (HI) encephalopathy are limited, in part, by the delay in instituting hypothermia and access to equipment. In a piglet model of HI, half of the neurons in putamen already showed ischemic cytopathology by 6 hours of recovery. We tested the hypothesis that treatment with the superoxide dismutase-catalase mimetic EUK-134 at 30 minutes of recovery provides additive neuronal protection when combined with 1 day of whole-body hypothermia implemented 4 hours after resuscitation. METHODS Anesthetized piglets were subjected to 40 minutes of hypoxia (10% inspired oxygen) followed by 7 minutes of airway occlusion and resuscitation. Body temperature was maintained at 38.5°C in normothermic groups and at 34°C in hypothermic groups. All groups were mechanically ventilated, sedated, and received muscle relaxants during the first day of recovery. Neuropathology was assessed by profile and stereological cell-counting methods. RESULTS At 10 days of recovery, neuronal viability in putamen of a normothermic group treated with saline vehicle was reduced to 17% ± 6% (±95% confidence interval) of the value in a sham-operated control group (100% ± 15%). Intravenous infusion of EUK-134 (2.5 mg/kg at 30 minutes of recovery + 1.25 mg/kg/h until 4 hours of recovery) with normothermic recovery resulted in 40% ± 12% viable neurons in putamen. Treatment with saline vehicle followed by delayed hypothermia resulted in partial protection (46% ± 15%). Combining early EUK-134 treatment with delayed hypothermia also produced partial protection (47% ± 18%) that was not significantly greater than single treatment with EUK-134 (confidence interval of difference: -15% to 29%) or delayed hypothermia (-16% to 19%). Furthermore, no additive neuroprotection was detected in caudate nucleus or parasagittal neocortex, where neuronal loss was less severe. CONCLUSIONS We conclude that early treatment with this antioxidant does not substantially enhance the therapeutic benefit of delayed hypothermia in protecting highly vulnerable neurons in HI-insulted newborns, possibly because basal ganglia neurons are already undergoing irreversible cell death signaling by the time EUK-134 is administered or because this compound and hypothermia attenuate similar mechanisms of injury.
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Affiliation(s)
- Xinli Ni
- Department of Anesthesiology/Critical Care Medicine, Johns Hopkins University, Baltimore, MD 21287-4961, USA
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Hüttemann M, Helling S, Sanderson TH, Sinkler C, Samavati L, Mahapatra G, Varughese A, Lu G, Liu J, Ramzan R, Vogt S, Grossman LI, Doan JW, Marcus K, Lee I. Regulation of mitochondrial respiration and apoptosis through cell signaling: cytochrome c oxidase and cytochrome c in ischemia/reperfusion injury and inflammation. BIOCHIMICA ET BIOPHYSICA ACTA 2012; 1817:598-609. [PMID: 21771582 PMCID: PMC3229836 DOI: 10.1016/j.bbabio.2011.07.001] [Citation(s) in RCA: 194] [Impact Index Per Article: 16.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/30/2011] [Revised: 06/30/2011] [Accepted: 07/01/2011] [Indexed: 01/09/2023]
Abstract
Cytochrome c (Cytc) and cytochrome c oxidase (COX) catalyze the terminal reaction of the mitochondrial electron transport chain (ETC), the reduction of oxygen to water. This irreversible step is highly regulated, as indicated by the presence of tissue-specific and developmentally expressed isoforms, allosteric regulation, and reversible phosphorylations, which are found in both Cytc and COX. The crucial role of the ETC in health and disease is obvious since it, together with ATP synthase, provides the vast majority of cellular energy, which drives all cellular processes. However, under conditions of stress, the ETC generates reactive oxygen species (ROS), which cause cell damage and trigger death processes. We here discuss current knowledge of the regulation of Cytc and COX with a focus on cell signaling pathways, including cAMP/protein kinase A and tyrosine kinase signaling. Based on the crystal structures we highlight all identified phosphorylation sites on Cytc and COX, and we present a new phosphorylation site, Ser126 on COX subunit II. We conclude with a model that links cell signaling with the phosphorylation state of Cytc and COX. This in turn regulates their enzymatic activities, the mitochondrial membrane potential, and the production of ATP and ROS. Our model is discussed through two distinct human pathologies, acute inflammation as seen in sepsis, where phosphorylation leads to strong COX inhibition followed by energy depletion, and ischemia/reperfusion injury, where hyperactive ETC complexes generate pathologically high mitochondrial membrane potentials, leading to excessive ROS production. Although operating at opposite poles of the ETC activity spectrum, both conditions can lead to cell death through energy deprivation or ROS-triggered apoptosis.
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Affiliation(s)
- Maik Hüttemann
- Wayne State University School of Medicine, Detroit, MI 48201, USA.
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Yang ZJ, Carter EL, Kibler KK, Kwansa H, Crafa DA, Martin LJ, Roman RJ, Harder DR, Koehler RC. Attenuation of neonatal ischemic brain damage using a 20-HETE synthesis inhibitor. J Neurochem 2012; 121:168-79. [PMID: 22251169 PMCID: PMC3303996 DOI: 10.1111/j.1471-4159.2012.07666.x] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
20-Hydroxyeicosatetraenoic acid (20-HETE) is a cytochrome P450 metabolite of arachidonic acid that that contributes to infarct size following focal cerebral ischemia. However, little is known about the role of 20-HETE in global cerebral ischemia or neonatal hypoxia-ischemia (H-I). The present study examined the effects of blockade of the synthesis of 20-HETE with N-hydroxy-N'-(4-n-butyl-2-methylphenyl) formamidine (HET0016) in neonatal piglets after H-I to determine if it protects highly vulnerable striatal neurons. Administration of HET0016 after H-I improved early neurological recovery and protected neurons in putamen after 4 days of recovery. HET0016 had no significant effect on cerebral blood flow. cytochrome P450 4A immunoreactivity was detected in putamen neurons, and direct infusion of 20-HETE in the putamen increased phosphorylation of Na(+), K(+) -ATPase and NMDA receptor NR1 subunit selectively at protein kinase C-sensitive sites but not at protein kinase A-sensitive sites. HET0016 selectively inhibited the H-I induced phosphorylation at these same sites at 3 h of recovery and improved Na(+), K(+) -ATPase activity. At 3 h, HET0016 also suppressed H-I induced extracellular signal-regulated kinase 1/2 activation and protein markers of nitrosative and oxidative stress. Thus, 20-HETE can exert direct effects on key proteins involved in neuronal excitotoxicity in vivo and contributes to neurodegeneration after global cerebral ischemia in immature brain.
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Affiliation(s)
- Zeng-Jin Yang
- Department of Anesthesiology and Critical Care Medicine, Johns Hopkins University, Baltimore, MD 21205, USA.
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Ni X, Yang ZJ, Carter EL, Martin LJ, Koehler RC. Striatal neuroprotection from neonatal hypoxia-ischemia in piglets by antioxidant treatment with EUK-134 or edaravone. Dev Neurosci 2011; 33:299-311. [PMID: 21701140 DOI: 10.1159/000327243] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2010] [Accepted: 12/15/2010] [Indexed: 11/19/2022] Open
Abstract
Striatal neurons are highly vulnerable to hypoxia-ischemia (HI) in term newborns. In a piglet model of HI, striatal neurons develop oxidative stress and organelle disruption by 3-6 h of recovery and ischemic cytopathology over 6-24 h of recovery. We tested the hypothesis that early treatment with the antioxidants EUK-134 (a manganese-salen derivative that acts as a scavenger of superoxide, hydrogen peroxide, nitric oxide or NO and peroxynitrite) or edaravone (MCI-186, a scavenger of hydroxyl radical and NO) protects striatal neurons from HI. Anesthetized newborn piglets were subjected to 40 min of hypoxia and 7 min of airway occlusion. At 30 min after resuscitation, the piglets received vehicle, EUK-134 or edaravone. Drug treatment did not affect arterial blood pressure, blood gases, blood glucose or rectal temperature. At 4 days of recovery, the density of viable neurons in the putamen of vehicle-treated piglets was 12 ± 6% (±SD) of sham-operated control density. Treatment with EUK-134 increased viability to 41 ± 17%, and treatment with edaravone increased viability to 39 ± 19%. In the caudate nucleus, neuronal viability was increased from 54 ± 11% in the vehicle group to 78 ± 15% in the EUK-134 group and to 73 ± 13% in the edaravone group. Antioxidant drug treatment accelerated recovery from neurologic deficits and decreased oxidative and nitrative damage to nucleic acids. Treatment with EUK-134 reduced the HI-induced formation of protein carbonyl groups and tyrosine nitration at 3 h of recovery. We conclude that systemic administration of antioxidant agents by 30 min after resuscitation from HI can reduce oxidative stress and salvage neurons in the highly vulnerable striatum in a large-animal model of neonatal HI. Therefore, oxidative stress is an important mechanism for this injury, and antioxidant therapy is a rational, mechanism-based approach to neuroprotection in the newborn brain.
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Affiliation(s)
- Xinli Ni
- Department of Anesthesiology and Critical Care Medicine, Johns Hopkins University, Baltimore, MD 21287-4961, USA
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Northington FJ, Chavez-Valdez R, Martin LJ. Neuronal cell death in neonatal hypoxia-ischemia. Ann Neurol 2011; 69:743-58. [PMID: 21520238 DOI: 10.1002/ana.22419] [Citation(s) in RCA: 269] [Impact Index Per Article: 20.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Perinatal hypoxic-ischemic encephalopathy (HIE) is a significant cause of mortality and morbidity in infants and young children. Therapeutic opportunities are very limited for neonatal and pediatric HIE. Specific neural systems and populations of cells are selectively vulnerable in HIE; however, the mechanisms of degeneration are unresolved. These mechanisms involve oxidative stress, excitotoxicity, inflammation, and the activation of several different cell death pathways. Decades ago the structural and mechanistic basis of the cellular degeneration in HIE was thought to be necrosis. Subsequently, largely due to advances in cell biology and to experimental animal studies, emphasis has been switched to apoptosis or autophagy mediated by programmed cell death (PCD) mechanisms as important forms of degeneration in HIE. We have conceptualized based on morphological and biochemical data that this degeneration is better classified according to an apoptosis-necrosis cell death continuum and that programmed cell necrosis has prominent contribution in the neurodegeneration of HIE in animal models. It is likely that neonatal HIE evolves through many cell death chreodes influenced by the dynamic injury landscape. The relevant injury mechanisms remain to be determined in human neonatal HIE, though preliminary work suggests a complexity in the cell death mechanisms greater than that anticipated from experimental animal models. The accurate identification of the various cell death chreodes and their mechanisms unfolding within the immature brain matrix could provide fresh insight for developing meaningful therapies for neonatal and pediatric HIE.
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Affiliation(s)
- Frances J Northington
- Division of Neonatology, Department of Pediatrics, Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA.
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