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Bi Y, Yu W, Bian W, Jin M, He Y, Wang J, Miao X, Guo T, Ma X, Gong P, Li R, Xi J, Guo S, Gao Z. Metabolic and Microbial Dysregulation in Preterm Infants with Neonatal Respiratory Distress Syndrome: An Early Developmental Perspective. J Proteome Res 2024; 23:3460-3468. [PMID: 39013122 DOI: 10.1021/acs.jproteome.4c00114] [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] [Indexed: 07/18/2024]
Abstract
Neonatal respiratory distress syndrome (NRDS) is one of the most severe respiratory disorders in preterm infants (PTIs) due to immature lung development. To delineate the serum metabolic alterations and gut microbiota variations in NRDS and assess their implications on neonatal development, we enrolled 13 NRDS neonates and 12 PTIs and collected fecal and serum specimens after birth. Longitudinal fecal sampling was conducted weekly for a month in NRDS neonates. NRDS neonates were characterized by notably reduced gestational ages and birth weights and a higher rate of asphyxia at birth relative to PTIs. Early postnatal disturbances in tryptophan metabolism were evident in the NRDS group, concomitant with elevated relative abundance of Haemophilus, Fusicatenibacter, and Vibrio. Integrative multiomics analyses revealed an inverse relationship between tryptophan concentrations and Blautia abundance. At one-week old, NRDS neonates exhibited cortisol regulation anomalies and augmented hepatic catabolism. Sequential microbial profiling revealed distinct gut microbiota evolution in NRDS subjects, characterized by a general reduction in potentially pathogenic bacteria. The acute perinatal stress of NRDS leads to mitochondrial compromise, hormonal imbalance, and delayed gut microbiota evolution. Despite the short duration of NRDS, its impact on neonatal development is significant and requires extended attention.
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Affiliation(s)
- Yanxu Bi
- Department of Pediatrics, Linfen Central Hospital, Linfen 041000, China
| | - Wenyi Yu
- Department of Respiratory and Critical Care Medicine, Peking University People's Hospital, Beijing 100044, China
| | - Wenjie Bian
- Department of Respiratory and Critical Care Medicine, Peking University People's Hospital, Beijing 100044, China
| | - Mengtong Jin
- Linfen Clinical Medicine Research Center, Linfen 041000, China
| | - Yukun He
- Department of Respiratory and Critical Care Medicine, Peking University People's Hospital, Beijing 100044, China
| | - Jinglei Wang
- Department of Pediatrics, Linfen Central Hospital, Linfen 041000, China
| | - Xiaofeng Miao
- Linfen Clinical Medicine Research Center, Linfen 041000, China
| | - Tiantian Guo
- Linfen Clinical Medicine Research Center, Linfen 041000, China
| | - Xiaojun Ma
- Department of Respiratory and Critical Care Medicine, Linfen Central Hospital, Linfen 041000, China
| | - Pihua Gong
- Department of Respiratory and Critical Care Medicine, Peking University People's Hospital, Beijing 100044, China
| | - Ran Li
- Department of Respiratory and Critical Care Medicine, Peking University People's Hospital, Beijing 100044, China
| | - Jiangli Xi
- Department of Pediatrics, Linfen Central Hospital, Linfen 041000, China
| | - Shuming Guo
- Linfen Clinical Medicine Research Center, Linfen 041000, China
- Institute of Chest and Lung Diseases, Shanxi Medical University, Taiyuan 030001, China
| | - Zhancheng Gao
- Department of Respiratory and Critical Care Medicine, Peking University People's Hospital, Beijing 100044, China
- Institute of Chest and Lung Diseases, Shanxi Medical University, Taiyuan 030001, China
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Curel CJM, Nobeli I, Thornton C. Leflunomide Treatment Does Not Protect Neural Cells following Oxygen-Glucose Deprivation (OGD) In Vitro. Cells 2024; 13:631. [PMID: 38607070 PMCID: PMC11011260 DOI: 10.3390/cells13070631] [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: 01/31/2024] [Revised: 03/25/2024] [Accepted: 03/29/2024] [Indexed: 04/13/2024] Open
Abstract
Neonatal hypoxia-ischemia (HI) affects 2-3 per 1000 live births in developed countries and up to 26 per 1000 live births in developing countries. It is estimated that of the 750,000 infants experiencing a hypoxic-ischemic event during birth per year, more than 400,000 will be severely affected. As treatment options are limited, rapidly identifying new therapeutic avenues is critical, and repurposing drugs already in clinical use offers a fast-track route to clinic. One emerging avenue for therapeutic intervention in neonatal HI is to target mitochondrial dysfunction, which occurs early in the development of brain injury. Mitochondrial dynamics are particularly affected, with mitochondrial fragmentation occurring at the expense of the pro-fusion protein Optic Atrophy (OPA)1. OPA1, together with mitofusins (MFN)1/2, are required for membrane fusion, and therefore, protecting their function may also safeguard mitochondrial dynamics. Leflunomide, an FDA-approved immunosuppressant, was recently identified as an activator of MFN2 with partial effects on OPA1 expression. We, therefore, treated C17.2 cells with Leflunomide before or after oxygen-glucose deprivation, an in vitro mimic of HI, to determine its efficacy as a neuroprotection and inhibitor of mitochondrial dysfunction. Leflunomide increased baseline OPA1 but not MFN2 expression in C17.2 cells. However, Leflunomide was unable to promote cell survival following OGD. Equally, there was no obvious effect on mitochondrial morphology or bioenergetics. These data align with studies suggesting that the tissue and mitochondrial protein profile of the target cell/tissue are critical for taking advantage of the therapeutic actions of Leflunomide.
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Affiliation(s)
- Claire J. M. Curel
- Department of Comparative Biomedical Sciences, Royal Veterinary College, London NW1 0TU, UK
| | - Irene Nobeli
- School of Natural Sciences, Institute of Structural and Molecular Biology, Birkbeck, University of London, London WC1E 7HX, UK
| | - Claire Thornton
- Department of Comparative Biomedical Sciences, Royal Veterinary College, London NW1 0TU, UK
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Jagečić D, Petrović DJ, Šimunić I, Isaković J, Mitrečić D. The Oxygen and Glucose Deprivation of Immature Cells of the Nervous System Exerts Distinct Effects on Mitochondria, Mitophagy, and Autophagy, Depending on the Cells' Differentiation Stage. Brain Sci 2023; 13:910. [PMID: 37371388 DOI: 10.3390/brainsci13060910] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2023] [Revised: 04/28/2023] [Accepted: 05/31/2023] [Indexed: 06/29/2023] Open
Abstract
Perinatal brain damage, one of the most common causes of lifelong impairment, is predominantly caused by a lack of oxygen and glucose during early development. These conditions, in turn, affect cells of the nervous tissue through various stages of their maturation. To quantify the influence of these factors on cell differentiation and mitochondrial parameters, we exposed neural cell precursors to oxygen and glucose deprivation (OGD) during three stages of their differentiation: day 1, day 7, and day 14 (D1, D7, and D14, respectively). The obtained results show that OGD slows down cellular differentiation and causes cell death. Regardless of the level of cell maturity, the overall area of the mitochondria, their length, and the branching of their filaments decreased uniformly when exposed to OGD-related stress. Moreover, the cells in all stages of differentiation exhibited an increase in ROS production, hyperpolarization of the mitochondrial membrane, and autophagy. Interestingly, day 7 was the only stage in which a significant increase in mitochondrial fission, along with measurable instances of mitophagy, were detected. Taken together, the results of this study suggest that, apart from common reactions to a sudden lack of oxygen and glucose, cells in specific stages of neural differentiation can also exhibit increased preferences for mitochondrial fission and mitophagy. Such findings could play a role in guiding the future development of novel therapeutic approaches targeting perinatal brain damage during specific stages of nervous system development.
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Affiliation(s)
- Denis Jagečić
- Laboratory for Stem Cells, Croatian Institute for Brain Research, University of Zagreb School of Medicine, Šalata 3, 10 000 Zagreb, Croatia
| | - Dražen Juraj Petrović
- Laboratory for Stem Cells, Croatian Institute for Brain Research, University of Zagreb School of Medicine, Šalata 3, 10 000 Zagreb, Croatia
- Genos d.o.o., Laboratory for Glycobiology, 10 000 Zagreb, Croatia
| | - Iva Šimunić
- Laboratory for Stem Cells, Croatian Institute for Brain Research, University of Zagreb School of Medicine, Šalata 3, 10 000 Zagreb, Croatia
| | - Jasmina Isaković
- Laboratory for Stem Cells, Croatian Institute for Brain Research, University of Zagreb School of Medicine, Šalata 3, 10 000 Zagreb, Croatia
- Omnion Research International, 10 000 Zagreb, Croatia
| | - Dinko Mitrečić
- Laboratory for Stem Cells, Croatian Institute for Brain Research, University of Zagreb School of Medicine, Šalata 3, 10 000 Zagreb, Croatia
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Li M, Tang H, Li Z, Tang W. Emerging Treatment Strategies for Cerebral Ischemia-Reperfusion Injury. Neuroscience 2022; 507:112-124. [PMID: 36341725 DOI: 10.1016/j.neuroscience.2022.10.020] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2022] [Revised: 10/19/2022] [Accepted: 10/21/2022] [Indexed: 11/06/2022]
Abstract
Cerebral ischemia-reperfusion injury (CI/RI) injury is a common feature of ischemic stroke which occurs when the blood supply is restored after a period of ischemia in the brain. Reduced blood-flow to the brain during CI/RI compromises neuronal cell health as a result of mitochondrial dysfunction, oxidative stress, cytokine production, inflammation and tissue damage. Reperfusion therapy during CI/RI can restore the blood flow to ischemic regions of brain which are not yet infarcted. The long-term goal of CI/RI therapy is to reduce stroke-related neuronal cell death, disability and mortality. A range of drug and interventional therapies have emerged that can alleviate CI/RI mediated oxidative stress, inflammation and apoptosis in the brain. Herein, we review recent studies on CI/RI interventions for which a mechanism of action has been described and the potential of these therapeutic modalities for future use in the clinic.
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Affiliation(s)
- Mengxing Li
- College of Acupuncture and Massage (Rehabilitation Medical College), Anhui University of Chinese Medicine, Hefei 230012, China
| | - Heyong Tang
- College of Integrated Chinese and Western Medicine (School of Life Sciences), Anhui University of Chinese Medicine, Hefei 230012, China
| | - Zhen Li
- College of Acupuncture and Massage (Rehabilitation Medical College), Anhui University of Chinese Medicine, Hefei 230012, China
| | - Wei Tang
- College of Acupuncture and Massage (Rehabilitation Medical College), Anhui University of Chinese Medicine, Hefei 230012, China.
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Romero-Morales AI, Gama V. Revealing the Impact of Mitochondrial Fitness During Early Neural Development Using Human Brain Organoids. Front Mol Neurosci 2022; 15:840265. [PMID: 35571368 PMCID: PMC9102998 DOI: 10.3389/fnmol.2022.840265] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2021] [Accepted: 04/04/2022] [Indexed: 11/13/2022] Open
Abstract
Mitochondrial homeostasis -including function, morphology, and inter-organelle communication- provides guidance to the intrinsic developmental programs of corticogenesis, while also being responsive to environmental and intercellular signals. Two- and three-dimensional platforms have become useful tools to interrogate the capacity of cells to generate neuronal and glia progeny in a background of metabolic dysregulation, but the mechanistic underpinnings underlying the role of mitochondria during human neurogenesis remain unexplored. Here we provide a concise overview of cortical development and the use of pluripotent stem cell models that have contributed to our understanding of mitochondrial and metabolic regulation of early human brain development. We finally discuss the effects of mitochondrial fitness dysregulation seen under stress conditions such as metabolic dysregulation, absence of developmental apoptosis, and hypoxia; and the avenues of research that can be explored with the use of brain organoids.
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Affiliation(s)
| | - Vivian Gama
- Department of Cell and Developmental Biology, Vanderbilt University, Nashville, TN, United States
- Vanderbilt Center for Stem Cell Biology, Vanderbilt University, Nashville, TN, United States
- Vanderbilt Brain Institute, Vanderbilt University, Nashville, TN, United States
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Xiong Q, Li X, Xia L, Yao Z, Shi X, Dong Z. Dihydroartemisinin attenuates hypoxic-ischemic brain damage in neonatal rats by inhibiting oxidative stress. Mol Brain 2022; 15:36. [PMID: 35484595 PMCID: PMC9052669 DOI: 10.1186/s13041-022-00921-y] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2022] [Accepted: 04/13/2022] [Indexed: 02/08/2023] Open
Abstract
Neonatal hypoxic-ischemic encephalopathy (HIE) induced by perinatal asphyxia is a major cause of neurological disability among infants. Dihydroartemisinin (DHA), derived from artemisinin, well known as an anti-malarial medicine, was proved to be able to inhibit oxidative stress and inflammation. However, whether those functions of DHA play roles in hypoxic-ischemic brain damage (HIBD), an animal model of HIE in patient which also been observed to have oxidative stress and inflammation, is unknown. In this study, we demonstrated that the DHA treatment on newborn rats significantly relieved the neuron loss and motor and cognitive impairment caused by HIBD. One of the underlying mechanisms is that DHA enhanced the anti-oxidant capacity of HIBD rats by up-regulating the total antioxidant capacity (T-AOC), gluathione reductase (GR) and catalase (CAT) while down regulating the pro-oxidative substances including hydrogen peroxide (H2O2), total nitric oxide synthase (T-NOS) and inducible nitric oxide synthase (iNOS). Thus, our study illustrated that DHA could alleviate the damage of brains and improve the cognitive and motor function of HIBD rats by inhibiting oxidative stress, provided an opportunity to interrogate potential therapeutics for affected HIE patients.
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Affiliation(s)
- Qian Xiong
- Pediatric Research Institute, Ministry of Education Key Laboratory of Child Development and Disorders, National Clinical Research Center for Child Health and Disorders, China International Science and Technology Cooperation Base of Child Development and Critical Disorders, Chongqing Key Laboratory of Translational Medical Research in Cognitive Development and Learning and Memory Disorders, Children's Hospital of Chongqing Medical University, Chongqing, 400014, China
| | - Xiaohuan Li
- Pediatric Research Institute, Ministry of Education Key Laboratory of Child Development and Disorders, National Clinical Research Center for Child Health and Disorders, China International Science and Technology Cooperation Base of Child Development and Critical Disorders, Chongqing Key Laboratory of Translational Medical Research in Cognitive Development and Learning and Memory Disorders, Children's Hospital of Chongqing Medical University, Chongqing, 400014, China
| | - Lei Xia
- Pediatric Research Institute, Ministry of Education Key Laboratory of Child Development and Disorders, National Clinical Research Center for Child Health and Disorders, China International Science and Technology Cooperation Base of Child Development and Critical Disorders, Chongqing Key Laboratory of Translational Medical Research in Cognitive Development and Learning and Memory Disorders, Children's Hospital of Chongqing Medical University, Chongqing, 400014, China
| | - Zhengyu Yao
- Pediatric Research Institute, Ministry of Education Key Laboratory of Child Development and Disorders, National Clinical Research Center for Child Health and Disorders, China International Science and Technology Cooperation Base of Child Development and Critical Disorders, Chongqing Key Laboratory of Translational Medical Research in Cognitive Development and Learning and Memory Disorders, Children's Hospital of Chongqing Medical University, Chongqing, 400014, China
| | - Xiuyu Shi
- Pediatric Research Institute, Ministry of Education Key Laboratory of Child Development and Disorders, National Clinical Research Center for Child Health and Disorders, China International Science and Technology Cooperation Base of Child Development and Critical Disorders, Chongqing Key Laboratory of Translational Medical Research in Cognitive Development and Learning and Memory Disorders, Children's Hospital of Chongqing Medical University, Chongqing, 400014, China.
| | - Zhifang Dong
- Pediatric Research Institute, Ministry of Education Key Laboratory of Child Development and Disorders, National Clinical Research Center for Child Health and Disorders, China International Science and Technology Cooperation Base of Child Development and Critical Disorders, Chongqing Key Laboratory of Translational Medical Research in Cognitive Development and Learning and Memory Disorders, Children's Hospital of Chongqing Medical University, Chongqing, 400014, China.
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7
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Spees WM, Sukstanskii AL, Bretthorst GL, Neil JJ, Ackerman JJH. Rat Brain Global Ischemia-Induced Diffusion Changes Revisited: Biophysical Modeling of the Water and NAA MR "Diffusion Signal". Magn Reson Med 2022; 88:1333-1346. [PMID: 35452137 DOI: 10.1002/mrm.29262] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2021] [Revised: 03/18/2022] [Accepted: 03/20/2022] [Indexed: 11/06/2022]
Abstract
PURPOSE To assess changes in intracellular diffusion as a mechanism for the reduction in water ADC that accompanies brain injury. Using NAA as a marker of neuronal cytoplasmic diffusion, NAA diffusion was measured before and after global ischemia (immediately postmortem) in the female Sprague-Dawley rat. METHODS Diffusion-weighted PRESS spectra, with diffusion encoding in a single direction, were acquired from large voxels of rat brain gray matter in vivo and postischemia employing either pairs of pulsed half-sine-shaped gradients (in vivo and postischemia, bmax = 19 ms/μm2 ) or sinusoidal oscillating gradients (in vivo only) with frequencies of 99.2-250 Hz. A 2D randomly oriented cylinder (neurite) model gave estimates of longitudinal and transverse diffusivities (DL and DT , respectively). In this model, DL represents the "free" diffusivity of NAA, whereas DT reflects highly restricted diffusion. Using oscillating gradients, the frequency dependence of DT [DT (ω)] gave estimates of the cylinder (axon/dendrite) radius. RESULTS A 10% decrease in DL,NAA followed global ischemia, dropping from 0.391 ± 0.012 μm2 /ms to 0.350 ± 0.009 μm2 /ms. Modeling DT,NAA (ω) provided an estimate of the neurite radius of 1.0 ± 0.6 μm. CONCLUSION Whereas the increase in apparent intraneuronal viscosity suggested by changes in DL,NAA may contribute to the overall reduction in water ADC associated with brain injury, it is not sufficient to be the sole explanation. Estimates of neurite radius based on DT (ω) were consistent with literature values.
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Affiliation(s)
- William M Spees
- Biomedical MR Laboratory, Mallinckrodt Institute of Radiology, Washington University School of Medicine, St. Louis, Missouri
| | - Alex L Sukstanskii
- Biomedical MR Laboratory, Mallinckrodt Institute of Radiology, Washington University School of Medicine, St. Louis, Missouri
| | - G Larry Bretthorst
- Biomedical MR Laboratory, Mallinckrodt Institute of Radiology, Washington University School of Medicine, St. Louis, Missouri
| | - Jeffrey J Neil
- Biomedical MR Laboratory, Mallinckrodt Institute of Radiology, Washington University School of Medicine, St. Louis, Missouri.,Department of Neurology, Washington University School of Medicine, St. Louis, Missouri.,Department of Pediatrics, Washington University School of Medicine, St. Louis, Missouri
| | - Joseph J H Ackerman
- Biomedical MR Laboratory, Mallinckrodt Institute of Radiology, Washington University School of Medicine, St. Louis, Missouri.,Department of Chemistry, Washington University, St. Louis, Missouri.,Department of Internal Medicine, Washington University School of Medicine, St. Louis, Missouri.,Alvin J Siteman Cancer Center, Washington University School of Medicine, St. Louis, Missouri
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Nair S, Leverin AL, Rocha-Ferreira E, Sobotka KS, Thornton C, Mallard C, Hagberg H. Induction of Mitochondrial Fragmentation and Mitophagy after Neonatal Hypoxia-Ischemia. Cells 2022; 11:cells11071193. [PMID: 35406757 PMCID: PMC8997592 DOI: 10.3390/cells11071193] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2021] [Revised: 03/25/2022] [Accepted: 03/30/2022] [Indexed: 11/16/2022] Open
Abstract
Hypoxia-ischemia (HI) leads to immature brain injury mediated by mitochondrial stress. If damaged mitochondria cannot be repaired, mitochondrial permeabilization ensues, leading to cell death. Non-optimal turnover of mitochondria is critical as it affects short and long term structural and functional recovery and brain development. Therefore, disposal of deficient mitochondria via mitophagy and their replacement through biogenesis is needed. We utilized mt-Keima reporter mice to quantify mitochondrial morphology (fission, fusion) and mitophagy and their mechanisms in primary neurons after Oxygen Glucose Deprivation (OGD) and in brain sections after neonatal HI. Molecular mechanisms of PARK2-dependent and -independent pathways of mitophagy were investigated in vivo by PCR and Western blotting. Mitochondrial morphology and mitophagy were investigated using live cell microscopy. In primary neurons, we found a primary fission wave immediately after OGD with a significant increase in mitophagy followed by a secondary phase of fission at 24 h following recovery. Following HI, mitophagy was upregulated immediately after HI followed by a second wave at 7 days. Western blotting suggests that both PINK1/Parkin-dependent and -independent mechanisms, including NIX and FUNDC1, were upregulated immediately after HI, whereas a PINK1/Parkin mechanism predominated 7 days after HI. We hypothesize that excessive mitophagy in the early phase is a pathologic response which may contribute to secondary energy depletion, whereas secondary mitophagy may be involved in post-HI regeneration and repair.
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Affiliation(s)
- Syam Nair
- Centre of Perinatal Medicine and Health, The Sahlgrenska Academy, University of Gothenburg, 41685 Gothenburg, Sweden; (A.-L.L.); (E.R.-F.); (K.S.S.); (C.M.); (H.H.)
- Institute of Neuroscience and Physiology, The Sahlgrenska Academy, University of Gothenburg, 41390 Gothenburg, Sweden
- Institute of Clinical Sciences, The Sahlgrenska Academy, University of Gothenburg, 41685 Gothenburg, Sweden
- Correspondence:
| | - Anna-Lena Leverin
- Centre of Perinatal Medicine and Health, The Sahlgrenska Academy, University of Gothenburg, 41685 Gothenburg, Sweden; (A.-L.L.); (E.R.-F.); (K.S.S.); (C.M.); (H.H.)
- Institute of Neuroscience and Physiology, The Sahlgrenska Academy, University of Gothenburg, 41390 Gothenburg, Sweden
| | - Eridan Rocha-Ferreira
- Centre of Perinatal Medicine and Health, The Sahlgrenska Academy, University of Gothenburg, 41685 Gothenburg, Sweden; (A.-L.L.); (E.R.-F.); (K.S.S.); (C.M.); (H.H.)
- Institute of Neuroscience and Physiology, The Sahlgrenska Academy, University of Gothenburg, 41390 Gothenburg, Sweden
- Institute of Clinical Sciences, The Sahlgrenska Academy, University of Gothenburg, 41685 Gothenburg, Sweden
| | - Kristina S. Sobotka
- Centre of Perinatal Medicine and Health, The Sahlgrenska Academy, University of Gothenburg, 41685 Gothenburg, Sweden; (A.-L.L.); (E.R.-F.); (K.S.S.); (C.M.); (H.H.)
- Institute of Neuroscience and Physiology, The Sahlgrenska Academy, University of Gothenburg, 41390 Gothenburg, Sweden
| | - Claire Thornton
- Department of Comparative Biomedical Sciences, Royal Veterinary College, London NW1 0TU, UK;
| | - Carina Mallard
- Centre of Perinatal Medicine and Health, The Sahlgrenska Academy, University of Gothenburg, 41685 Gothenburg, Sweden; (A.-L.L.); (E.R.-F.); (K.S.S.); (C.M.); (H.H.)
- Institute of Neuroscience and Physiology, The Sahlgrenska Academy, University of Gothenburg, 41390 Gothenburg, Sweden
| | - Henrik Hagberg
- Centre of Perinatal Medicine and Health, The Sahlgrenska Academy, University of Gothenburg, 41685 Gothenburg, Sweden; (A.-L.L.); (E.R.-F.); (K.S.S.); (C.M.); (H.H.)
- Institute of Clinical Sciences, The Sahlgrenska Academy, University of Gothenburg, 41685 Gothenburg, Sweden
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Mitochondrial dynamics in the neonatal brain - a potential target following injury? Biosci Rep 2022; 42:231001. [PMID: 35319070 PMCID: PMC8965818 DOI: 10.1042/bsr20211696] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2022] [Revised: 03/09/2022] [Accepted: 03/11/2022] [Indexed: 02/08/2023] Open
Abstract
The impact of birth asphyxia and its sequelae, hypoxic–ischaemic (HI) brain injury, is long-lasting and significant, both for the infant and for their family. Treatment options are limited to therapeutic hypothermia, which is not universally successful and is unavailable in low resource settings. The energy deficits that accompany neuronal death following interruption of blood flow to the brain implicate mitochondrial dysfunction. Such HI insults trigger mitochondrial outer membrane permeabilisation leading to release of pro-apoptotic proteins into the cytosol and cell death. More recently, key players in mitochondrial fission and fusion have been identified as targets following HI brain injury. This review aims to provide an introduction to the molecular players and pathways driving mitochondrial dynamics, the regulation of these pathways and how they are altered following HI insult. Finally, we review progress on repurposing or repositioning drugs already approved for other indications, which may target mitochondrial dynamics and provide promising avenues for intervention following brain injury. Such repurposing may provide a mechanism to fast-track, low-cost treatment options to the clinic.
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Ovcjak A, Xiao A, Kim JS, Xu B, Szeto V, Turlova E, Abussaud A, Chen NH, Miller SP, Sun HS, Feng ZP. Ryanodine receptor inhibitor dantrolene reduces hypoxic-ischemic brain injury in neonatal mice. Exp Neurol 2022; 351:113985. [DOI: 10.1016/j.expneurol.2022.113985] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2021] [Revised: 01/07/2022] [Accepted: 01/13/2022] [Indexed: 11/04/2022]
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Rodríguez M, Valez V, Cimarra C, Blasina F, Radi R. Hypoxic-Ischemic Encephalopathy and Mitochondrial Dysfunction: Facts, Unknowns, and Challenges. Antioxid Redox Signal 2020; 33:247-262. [PMID: 32295425 DOI: 10.1089/ars.2020.8093] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Significance: Hypoxic-ischemic events due to intrapartum complications represent the second cause of neonatal mortality and initiate an acute brain disorder known as hypoxic-ischemic encephalopathy (HIE). In HIE, the brain undergoes primary and secondary energy failure phases separated by a latent phase in which partial neuronal recovery is observed. A hypoxic-ischemic event leads to oxygen restriction causing ATP depletion, neuronal oxidative stress, and cell death. Mitochondrial dysfunction and enhanced oxidant formation in brain cells are characteristic phenomena associated with energy failure. Recent Advances: Mitochondrial sources of oxidants in neurons include complex I of the mitochondrial respiratory chain, as a key contributor to O2•- production via succinate by a reverse electron transport mechanism. The reaction of O2•- with nitric oxide (•NO) yields peroxynitrite, a mitochondrial and cellular toxin. Quantitation of the redox state of cytochrome c oxidase, through broadband near-infrared spectroscopy, represents a promising monitoring approach to evaluate mitochondrial dysfunction in vivo in humans, in conjunction with the determination of cerebral oxygenation and their correlation with the severity of brain injury. Critical Issues: The energetic failure being a key phenomenon in HIE connected with the severity of the encephalopathy, measurement of mitochondrial dysfunction in vivo provides an approach to assess evolution, prognosis, and adequate therapies. Restoration of mitochondrial redox homeostasis constitutes a key therapeutic goal. Future Directions: While hypothermia is the only currently accepted therapy in clinical management to preserve mitochondrial function, other mitochondria-targeted and/or redox-based treatments are likely to synergize to ensure further efficacy.
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Affiliation(s)
- Marianela Rodríguez
- Departamento de Bioquímica and Centro de Investigaciones Biomédicas (CEINBIO) and Facultad de Medicina, Hospital de Clínicas, Universidad de la República, Montevideo, Uruguay.,Departamento de Neonatología, Facultad de Medicina, Hospital de Clínicas, Universidad de la República, Montevideo, Uruguay
| | - Valeria Valez
- Departamento de Bioquímica and Centro de Investigaciones Biomédicas (CEINBIO) and Facultad de Medicina, Hospital de Clínicas, Universidad de la República, Montevideo, Uruguay
| | - Carolina Cimarra
- Departamento de Bioquímica and Centro de Investigaciones Biomédicas (CEINBIO) and Facultad de Medicina, Hospital de Clínicas, Universidad de la República, Montevideo, Uruguay
| | - Fernanda Blasina
- Departamento de Neonatología, Facultad de Medicina, Hospital de Clínicas, Universidad de la República, Montevideo, Uruguay
| | - Rafael Radi
- Departamento de Bioquímica and Centro de Investigaciones Biomédicas (CEINBIO) and Facultad de Medicina, Hospital de Clínicas, Universidad de la República, Montevideo, Uruguay
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12
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Chemo-Protective Potential of Cerium Oxide Nanoparticles against Fipronil-Induced Oxidative Stress, Apoptosis, Inflammation and Reproductive Dysfunction in Male White Albino Rats. Molecules 2020; 25:molecules25153479. [PMID: 32751827 PMCID: PMC7435388 DOI: 10.3390/molecules25153479] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2020] [Revised: 07/25/2020] [Accepted: 07/27/2020] [Indexed: 02/06/2023] Open
Abstract
Fipronil (FIP) is an insecticide commonly used in many fields, such as agriculture, veterinary medicine, and public health, and recently it has been proposed as a potential endocrine disrupter. The purpose of this study was to inspect the reproductive impacts of FIP and the possible protective effects of cerium nanoparticles (CeNPs) on male albino rats. Rats received FIP (5 mg/kg bwt; 1/20 LD50), CeNPs (35 mg/kg bwt) and FIP+CeNPs per os daily for 28 days. Serum testosterone levels, testicular oxidative damage, histopathological and immunohistochemical changes were evaluated. FIP provoked testicular oxidative damage as indicated by decreased serum testosterone (≈60%) and superoxide dismutase (≈50%), glutathione peroxidase activity (≈46.67%) and increased malondialdehyde (≈116.67%) and nitric oxide (≈87.5%) levels in testicular tissues. Furthermore, FIP induced edematous changes and degeneration within the seminiferous tubules, hyperplasia, vacuolations, and apoptosis in the epididymides. In addition, FIP exposure upregulated interleukin-1β (IL-1β), nitric oxide synthase 2 (NOS), caspase-3 (Casp3) and downregulated the Burkitt-cell lymphomas (BCL-2), inhibin B proteins (IBP), and androgen receptor (Ar) mRNA expressions Casp3, nitric oxide synthase (iNOS), ionized calcium-binding adapter molecule 1(IBA1), and IL-1β immunoreactions were increased. Also, reduction of proliferating cell nuclear antigen (PCNA), mouse vasa homologue (MVH), and SOX9 protein reactions were reported. Interestingly, CeNPs diminished the harmful impacts of FIP on testicular tissue by decreasing lipid peroxidation, apoptosis and inflammation and increasing the antioxidant activities. The findings reported herein showed that the CeNPs might serve as a supposedly new and efficient protective agent toward reproductive toxicity caused by the FIP insecticide in white male rats.
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13
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Corti O, Blomgren K, Poletti A, Beart PM. Autophagy in neurodegeneration: New insights underpinning therapy for neurological diseases. J Neurochem 2020; 154:354-371. [PMID: 32149395 DOI: 10.1111/jnc.15002] [Citation(s) in RCA: 80] [Impact Index Per Article: 20.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2018] [Revised: 02/27/2020] [Accepted: 03/05/2020] [Indexed: 12/13/2022]
Abstract
In autophagy long-lived proteins, protein aggregates or damaged organelles are engulfed by vesicles called autophagosomes prior to lysosomal degradation. Autophagy dysfunction is a hallmark of several neurodegenerative diseases in which misfolded proteins or dysfunctional mitochondria accumulate. Excessive autophagy can also exacerbate brain injury under certain conditions. In this review, we provide specific examples to illustrate the critical role played by autophagy in pathological conditions affecting the brain and discuss potential therapeutic implications. We show how a singular type of autophagy-dependent cell death termed autosis has attracted attention as a promising target for improving outcomes in perinatal asphyxia and hypoxic-ischaemic injury to the immature brain. We provide evidence that autophagy inhibition may be protective against radiotherapy-induced damage to the young brain. We describe a specialized form of macroautophagy of therapeutic relevance for motoneuron and neuromuscular diseases, known as chaperone-assisted selective autophagy, in which heat shock protein B8 is used to deliver aberrant proteins to autophagosomes. We summarize studies pinpointing mitophagy mediated by the serine/threonine kinase PINK1 and the ubiquitin-protein ligase Parkin as a mechanism potentially relevant to Parkinson's disease, despite debate over the physiological conditions in which it is activated in organisms. Finally, with the example of the autophagy-inducing agent rilmenidine and its discrepant effects in cell culture and mouse models of motor neuron disorders, we illustrate the importance of considering aspects such a disease stage and aggressiveness, type of insult and load of damaged or toxic cellular components, when choosing the appropriate drug, timepoint and duration of treatment.
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Affiliation(s)
- Olga Corti
- Institut National de la Santé et de la Recherche Médicale, Paris, France.,Centre National de la Recherche Scientifique, Paris, France.,Sorbonne Universités, Paris, France.,Institut du Cerveau et de la Moelle épinière, ICM, Paris, France
| | - Klas Blomgren
- Department of Women's and Children's Health, Karolinska Institutet, Stockholm, Sweden.,Department of Paediatric Oncology, Karolinska University Hospital, Stockholm, Sweden
| | - Angelo Poletti
- Dipartimento di Scienze Farmacologiche e Biomolecolari, Centro di Eccellenza sulle Malattie Neurodegenerative, Università degli Studi di Milano, Milan, Italy
| | - Philip M Beart
- Florey Institute of Neuroscience and Mental Health, University of Melbourne, Parkville, Vic, Australia.,Department of Pharmacology, University of Melbourne, Parkville, Vic, Australia
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14
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Gautam M, Xie EF, Kocak N, Ozdinler PH. Mitoautophagy: A Unique Self-Destructive Path Mitochondria of Upper Motor Neurons With TDP-43 Pathology Take, Very Early in ALS. Front Cell Neurosci 2019; 13:489. [PMID: 31787882 PMCID: PMC6854036 DOI: 10.3389/fncel.2019.00489] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2019] [Accepted: 10/17/2019] [Indexed: 12/13/2022] Open
Abstract
Mitochondrial dysfunction is one of the converging paths for many neurodegenerative diseases, including amyotrophic lateral sclerosis (ALS), and TDP-43 pathology is the most common proteinopathy detected in ALS and ALS/Frontotemporal lobar degeneration (ALS/FTLD). We recently identified mitochondrial problems in corticospinal motor neurons (CSMN) and in Betz cells of patients with TDP-43 pathology. However, the timing and the extent of mitochondrial defects, and their mode of degeneration have not been revealed. Because it is important to reveal when problems first begin to emerge and whether they are shared or unique, we investigated the health and integrity of mitochondria in CSMN of prpTDP-43A315T, PFN1G118V, and hSOD1G93A mice at P15 (post-natal day 15)—a very early age in mice without any sign of cellular degeneration.Utilization of immuno-coupled electron microscopy for a detailed surveillance of mitochondria in CSMN and other non-CSMN cells revealed presence of a novel self-destructive path of mitochondrial degeneration, which we named mitoautophagy. Mitoauthopgy is different from mitophagy, as it does not require autophagosome-mediated degradation. In contrast, in this novel path, mitochondria can clear themselves independently. We find that even at this early age, all diseased CSMN begin to display mitochondrial defects, whereas mitochondria in non-CSMN cells are healthy. Our findings not only reveal mitoautophagy as a novel path of mitochondrial clearance that occurs prior to neuronal vulnerability, but it also highlights that it is present mainly in the upper motor neurons of prpTDP-43A315T and PFN1G118V mice, which mimic many aspects of the disease in patients with TDP-43 pathology.
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Affiliation(s)
- Mukesh Gautam
- Davee Department of Neurology and Clinical Neurological Sciences, Northwestern University Feinberg School of Medicine, Chicago, IL, United States.,Les Turner ALS Center, Northwestern University Feinberg School of Medicine, Chicago, IL, United States
| | - Edward F Xie
- Davee Department of Neurology and Clinical Neurological Sciences, Northwestern University Feinberg School of Medicine, Chicago, IL, United States
| | - Nuran Kocak
- Davee Department of Neurology and Clinical Neurological Sciences, Northwestern University Feinberg School of Medicine, Chicago, IL, United States
| | - P Hande Ozdinler
- Davee Department of Neurology and Clinical Neurological Sciences, Northwestern University Feinberg School of Medicine, Chicago, IL, United States.,Les Turner ALS Center, Northwestern University Feinberg School of Medicine, Chicago, IL, United States.,Mesulam Cognitive Neurology and Alzheimer's Disease Center, Northwestern University Feinberg School of Medicine, Chicago, IL, United States.,Robert H. Lurie Comprehensive Cancer Research Center, Northwestern University Feinberg School of Medicine, Chicago, IL, United States
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15
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Mugisho OO, Rupenthal ID, Paquet-Durand F, Acosta ML, Green CR. Targeting connexin hemichannels to control the inflammasome: the correlation between connexin43 and NLRP3 expression in chronic eye disease. Expert Opin Ther Targets 2019; 23:855-863. [PMID: 31554417 DOI: 10.1080/14728222.2019.1673368] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Introduction: Chronic inflammatory diseases, including retinal diseases that are a major cause of vision loss, are associated with activation of the nucleotide-binding domain and leucine-rich repeat containing (NLR) protein-3 (NLRP3) inflammasome pathway. In chronic disease, the inflammasome becomes self-perpetuating, indicating a common pathway in such diseases irrespective of underlying etiology, and implying a shared solution is feasible. Connexin43 hemichannels correlate directly with NLRP3 inflammasome complex assembly (shown here in models of retinal disease). Connexin43 hemichannel-mediated ATP release is proposed to be the principal activator signal for inflammasome complex assembly in primary signal-sensitized cells. Connexin hemichannel block on its own is sufficient to inhibit the inflammasome pathway. Areas covered: We introduce chronic retinal disease, discuss available preclinical models and examine findings from these models regarding the targeting of connexin43 hemichannels and its effects on the inflammasome. Expert opinion: In over 25 animal disease models, connexin hemichannel regulation has shown therapeutic benefit, and one oral connexin hemichannel blocker, tonabersat (Xiflam), is Phase II ready with safety evidence in over 1000 patients. Regulating the connexin hemichannel provides a means to move quickly into clinical trials designed to ameliorate the progression of devastating chronic diseases of the eye, but also elsewhere in the body.
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Affiliation(s)
- Odunayo O Mugisho
- Buchanan Ocular Therapeutics Unit, Department of Ophthalmology, New Zealand National Eye Centre, University of Auckland , New Zealand
| | - Ilva D Rupenthal
- Buchanan Ocular Therapeutics Unit, Department of Ophthalmology, New Zealand National Eye Centre, University of Auckland , New Zealand
| | - Francois Paquet-Durand
- Cell Death Mechanisms Lab, Institute for Ophthalmic Research, University of Tübingen , Tübingen , Germany
| | - Monica L Acosta
- School of Optometry and Vision Science and the New Zealand National Eye Centre, University of Auckland , Auckland , New Zealand
| | - Colin R Green
- Department of Ophthalmology, New Zealand National Eye Centre, University of Auckland , Auckland , New Zealand
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16
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Singh-Mallah G, Nair S, Sandberg M, Mallard C, Hagberg H. The Role of Mitochondrial and Endoplasmic Reticulum Reactive Oxygen Species Production in Models of Perinatal Brain Injury. Antioxid Redox Signal 2019; 31:643-663. [PMID: 30957515 PMCID: PMC6657303 DOI: 10.1089/ars.2019.7779] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/28/2019] [Revised: 04/01/2019] [Accepted: 04/03/2019] [Indexed: 12/20/2022]
Abstract
Significance: Perinatal brain injury is caused by hypoxia-ischemia (HI) in term neonates, perinatal arterial stroke, and infection/inflammation leading to devastating long-term neurodevelopmental deficits. Therapeutic hypothermia is the only currently available treatment but is not successful in more than 50% of term neonates suffering from hypoxic-ischemic encephalopathy. Thus, there is an urgent unmet need for alternative or adjunct therapies. Reactive oxygen species (ROS) are important for physiological signaling, however, their overproduction/accumulation from mitochondria and endoplasmic reticulum (ER) during HI aggravate cell death. Recent Advances and Critical Issues: Mechanisms underlying ER stress-associated ROS production have been primarily elucidated using either non-neuronal cells or adult neurodegenerative experimental models. Findings from mature brain cannot be simply transferred to the immature brain. Therefore, age-specific studies investigating ER stress modulators may help investigate ER stress-associated ROS pathways in the immature brain. New therapeutics such as mitochondrial site-specific ROS inhibitors that selectively inhibit superoxide (O2•-)/hydrogen peroxide (H2O2) production are currently being developed. Future Directions: Because ER stress and oxidative stress accentuate each other, a combinatorial therapy utilizing both antioxidants and ER stress inhibitors may prove to be more protective against perinatal brain injury. Moreover, multiple relevant targets need to be identified for targeting ROS before they are formed. The role of organelle-specific ROS in brain repair needs investigation. Antioxid. Redox Signal. 31, 643-663.
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Affiliation(s)
- Gagandeep Singh-Mallah
- Institute of Biomedicine, Department of Medical Biochemistry, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
- Centre of Perinatal Medicine and Health, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
| | - Syam Nair
- Centre of Perinatal Medicine and Health, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
- Institute of Neuroscience and Physiology, Department of Physiology, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
- Institute of Clinical Sciences, Department of Obstetrics and Gynecology, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
| | - Mats Sandberg
- Institute of Biomedicine, Department of Medical Biochemistry, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
- Centre of Perinatal Medicine and Health, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
| | - Carina Mallard
- Centre of Perinatal Medicine and Health, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
- Institute of Neuroscience and Physiology, Department of Physiology, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
| | - Henrik Hagberg
- Centre of Perinatal Medicine and Health, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
- Institute of Clinical Sciences, Department of Obstetrics and Gynecology, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
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17
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Stepanova A, Sosunov S, Niatsetskaya Z, Konrad C, Starkov AA, Manfredi G, Wittig I, Ten V, Galkin A. Redox-Dependent Loss of Flavin by Mitochondrial Complex I in Brain Ischemia/Reperfusion Injury. Antioxid Redox Signal 2019; 31:608-622. [PMID: 31037949 PMCID: PMC6657304 DOI: 10.1089/ars.2018.7693] [Citation(s) in RCA: 37] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Aims: Brain ischemia/reperfusion (I/R) is associated with impairment of mitochondrial function. However, the mechanisms of mitochondrial failure are not fully understood. This work was undertaken to determine the mechanisms and time course of mitochondrial energy dysfunction after reperfusion following neonatal brain hypoxia-ischemia (HI) in mice. Results: HI/reperfusion decreased the activity of mitochondrial complex I, which was recovered after 30 min of reperfusion and then declined again after 1 h. Decreased complex I activity occurred in parallel with a loss in the content of noncovalently bound membrane flavin mononucleotide (FMN). FMN dissociation from the enzyme is caused by succinate-supported reverse electron transfer. Administration of FMN precursor riboflavin before HI/reperfusion was associated with decreased infarct volume, attenuation of neurological deficit, and preserved complex I activity compared with vehicle-treated mice. In vitro, the rate of FMN release during oxidation of succinate was not affected by the oxygen level and amount of endogenously produced reactive oxygen species. Innovation: Our data suggest that dissociation of FMN from mitochondrial complex I may represent a novel mechanism of enzyme inhibition defining respiratory chain failure in I/R. Strategies preventing FMN release during HI and reperfusion may limit the extent of energy failure and cerebral HI injury. The proposed mechanism of acute I/R-induced complex I impairment is distinct from the generally accepted mechanism of oxidative stress-mediated I/R injury. Conclusion: Our study is the first to highlight a critical role of mitochondrial complex I-FMN dissociation in the development of HI-reperfusion injury of the neonatal brain. Antioxid. Redox Signal. 31, 608-622.
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Affiliation(s)
- Anna Stepanova
- 1Division of Neonatology, Department of Pediatrics, Columbia University, New York, New York
| | - Sergey Sosunov
- 1Division of Neonatology, Department of Pediatrics, Columbia University, New York, New York
| | - Zoya Niatsetskaya
- 1Division of Neonatology, Department of Pediatrics, Columbia University, New York, New York
| | - Csaba Konrad
- 2Feil Family Brain and Mind Research Institute, Weill Cornell Medicine, New York, New York
| | - Anatoly A Starkov
- 2Feil Family Brain and Mind Research Institute, Weill Cornell Medicine, New York, New York
| | - Giovanni Manfredi
- 2Feil Family Brain and Mind Research Institute, Weill Cornell Medicine, New York, New York
| | - Ilka Wittig
- 3Functional Proteomics, SFB815 Core Unit, Medical School, Goethe University, Frankfurt, Germany.,4German Center for Cardiovascular Research (DZHK), Partner Site RheinMain, Frankfurt, Germany
| | - Vadim Ten
- 1Division of Neonatology, Department of Pediatrics, Columbia University, New York, New York
| | - Alexander Galkin
- 1Division of Neonatology, Department of Pediatrics, Columbia University, New York, New York
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18
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Stepanova A, Konrad C, Guerrero-Castillo S, Manfredi G, Vannucci S, Arnold S, Galkin A. Deactivation of mitochondrial complex I after hypoxia-ischemia in the immature brain. J Cereb Blood Flow Metab 2019; 39:1790-1802. [PMID: 29629602 PMCID: PMC6727140 DOI: 10.1177/0271678x18770331] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Mortality from perinatal hypoxic-ischemic (HI) brain injury reached 1.15 million worldwide in 2010 and is also a major factor for neurological disability in infants. HI directly influences the oxidative phosphorylation enzyme complexes in mitochondria, but the exact mechanism of HI-reoxygenation response in brain remains largely unresolved. After induction of HI-reoxygenation in postnatal day 10 rats, activities of mitochondrial respiratory chain enzymes were analysed and complexome profiling was performed. The effect of conformational state (active/deactive (A/D) transition) of mitochondrial complex I on H2O2 release was measured simultaneously with mitochondrial oxygen consumption. In contrast to cytochrome c oxidase and succinate dehydrogenase, HI-reoxygenation resulted in inhibition of mitochondrial complex I at 4 h after reoxygenation. Immediately after HI, we observed a robust increase in the content of deactive (D) form of complex I. The D-form is less active in reactive oxygen species (ROS) production via reversed electron transfer, indicating the key role of the deactivation of complex I in ischemia/reoxygenation. We describe a novel mechanism of mitochondrial response to ischemia in the immature brain. HI induced a deactivation of complex I in order to reduce ROS production following reoxygenation. Delayed activation of complex I represents a novel mitochondrial target for pathological-activated therapy.
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Affiliation(s)
- Anna Stepanova
- 1 School of Biological Sciences, Queen's University Belfast, Medical Biology Centre, Belfast, UK.,2 Feil Family Brain and Mind Research Institute, Weill Cornell Medicine, New York, NY, USA
| | - Csaba Konrad
- 2 Feil Family Brain and Mind Research Institute, Weill Cornell Medicine, New York, NY, USA
| | - Sergio Guerrero-Castillo
- 3 Radboud Center for Mitochondrial Medicine, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Giovanni Manfredi
- 2 Feil Family Brain and Mind Research Institute, Weill Cornell Medicine, New York, NY, USA
| | - Susan Vannucci
- 4 Department of Pediatrics/Newborn Medicine, Weill Cornell Medicine, New York, NY, USA
| | - Susanne Arnold
- 3 Radboud Center for Mitochondrial Medicine, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Alexander Galkin
- 1 School of Biological Sciences, Queen's University Belfast, Medical Biology Centre, Belfast, UK.,2 Feil Family Brain and Mind Research Institute, Weill Cornell Medicine, New York, NY, USA
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19
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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: 15] [Impact Index Per Article: 3.0] [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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20
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Yang L, Dong Y, Wu C, Li Y, Guo Y, Yang B, Zong X, Hamblin MR, Cheng-Yi Liu T, Zhang Q. Photobiomodulation preconditioning prevents cognitive impairment in a neonatal rat model of hypoxia-ischemia. JOURNAL OF BIOPHOTONICS 2019; 12:e201800359. [PMID: 30652418 PMCID: PMC6546525 DOI: 10.1002/jbio.201800359] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/20/2018] [Revised: 12/02/2018] [Accepted: 01/12/2019] [Indexed: 05/13/2023]
Abstract
Neonatal hypoxia-ischemia (HI) injury caused by oxygen deprivation is the most common cause of mortality and severe neurologic deficits in neonates. The present work evaluated the preventative effect of photobiomodulation (PBM) preconditioning, and its underlying mechanism of action on brain damage in an HI model in neonatal rats. According to the optimal time response of ATP levels in brain samples removed from normal rats, a PBM preconditioning (PBM-P) regimen (808 nm CW laser, 1 cm2 spot, 100 mW/cm2 , 12 J/cm2 ) was delivered to the scalp 6 hours before HI. PBM-P significantly attenuated cognitive impairment, volume shrinkage in the brain, neuron loss, dendritic and synaptic injury after HI. Further mechanistic investigation found that PBM-P could restore HI-induced mitochondrial dynamics and inhibit mitochondrial fragmentation, followed by a robust suppression of cytochrome c release, and prevention of neuronal apoptosis by inhibition of caspase activation. Our work suggests that PBM-P can attenuate HI-induced brain injury by maintaining mitochondrial dynamics and inhibiting the mitochondrial apoptotic pathway.
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Affiliation(s)
- Luodan Yang
- Laboratory of Laser Sports Medicine, College of Physical Education and Sports Science, South China Normal University, University Town, Guangzhou, GD 510006, China
- Department of Neuroscience & Regenerative Medicine, Medical College of Georgia, Augusta University, Augusta, GA 30912
| | - Yan Dong
- Department of Neuroscience & Regenerative Medicine, Medical College of Georgia, Augusta University, Augusta, GA 30912
| | - Chongyun Wu
- Laboratory of Laser Sports Medicine, College of Physical Education and Sports Science, South China Normal University, University Town, Guangzhou, GD 510006, China
| | - Yong Li
- Department of Neuroscience & Regenerative Medicine, Medical College of Georgia, Augusta University, Augusta, GA 30912
| | - Yichen Guo
- Department of Neuroscience & Regenerative Medicine, Medical College of Georgia, Augusta University, Augusta, GA 30912
| | - Baocheng Yang
- Department of Neuroscience & Regenerative Medicine, Medical College of Georgia, Augusta University, Augusta, GA 30912
| | - Xuemei Zong
- Department of Neuroscience & Regenerative Medicine, Medical College of Georgia, Augusta University, Augusta, GA 30912
| | - Michael R. Hamblin
- Wellman Center for Photomedicine, Massachusetts General Hospital, Boston, MA 02114, USA
- Department of Dermatology, Harvard Medical School, Boston, MA 02115, USA
- Harvard-MIT Division of Health Sciences and Technology, Cambridge, MA 02139, USA
| | - Timon Cheng-Yi Liu
- Laboratory of Laser Sports Medicine, College of Physical Education and Sports Science, South China Normal University, University Town, Guangzhou, GD 510006, China
| | - Quanguang Zhang
- Laboratory of Laser Sports Medicine, College of Physical Education and Sports Science, South China Normal University, University Town, Guangzhou, GD 510006, China
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21
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Zhou KQ, Green CR, Bennet L, Gunn AJ, Davidson JO. The Role of Connexin and Pannexin Channels in Perinatal Brain Injury and Inflammation. Front Physiol 2019; 10:141. [PMID: 30873043 PMCID: PMC6400979 DOI: 10.3389/fphys.2019.00141] [Citation(s) in RCA: 35] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2018] [Accepted: 02/07/2019] [Indexed: 12/21/2022] Open
Abstract
Perinatal brain injury remains a major cause of death and life-long disability. Perinatal brain injury is typically associated with hypoxia-ischemia and/or infection/inflammation. Both hypoxia-ischemia and infection trigger an inflammatory response in the brain. The inflammatory response can contribute to brain cell loss and chronic neuroinflammation leading to neurological impairments. It is now well-established that brain injury evolves over time, and shows a striking spread from injured to previously uninjured regions of the brain. There is increasing evidence that this spread is related to opening of connexin hemichannels and pannexin channels, both of which are large conductance membrane channels found in almost all cell types in the brain. Blocking connexin hemichannels within the first 3 h after hypoxia-ischemia has been shown to improve outcomes in term equivalent fetal sheep but it is important to also understand the downstream pathways linking membrane channel opening with the development of injury in order to identify new therapeutic targets. Open membrane channels release adenosine triphosphate (ATP), and other neuroactive molecules, into the extracellular space. ATP has an important physiological role, but has also been reported to act as a damage-associated molecular pattern (DAMP) signal mediated through specific purinergic receptors and so act as a primary signal 1 in the innate immune system inflammasome pathway. More crucially, extracellular ATP is a key inflammasome signal 2 activator, with purinergic receptor binding triggering the assembly of the multi-protein inflammasome complex. The inflammasome pathway and complex formation contribute to activation of inflammatory caspases, and the release of inflammatory cytokines, including interleukin (IL)-1β, tumor necrosis factor (TNF)-α, IL-18, and vascular endothelial growth factor (VEGF). We propose that the NOD-like receptor protein-3 (NLRP3) inflammasome, which has been linked to inflammatory responses in models of ischemic stroke and various inflammatory diseases, may be one mechanism by which connexin hemichannel opening especially mediates perinatal brain injury.
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Affiliation(s)
- Kelly Q Zhou
- Department of Physiology, The University of Auckland, Auckland, New Zealand
| | - Colin R Green
- Department of Ophthalmology, The University of Auckland, Auckland, New Zealand
| | - Laura Bennet
- Department of Physiology, The University of Auckland, Auckland, New Zealand
| | - Alistair J Gunn
- Department of Physiology, The University of Auckland, Auckland, New Zealand
| | - Joanne O Davidson
- Department of Physiology, The University of Auckland, Auckland, New Zealand.,Department of Ophthalmology, The University of Auckland, Auckland, New Zealand
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22
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Kim M, Stepanova A, Niatsetskaya Z, Sosunov S, Arndt S, Murphy MP, Galkin A, Ten VS. Attenuation of oxidative damage by targeting mitochondrial complex I in neonatal hypoxic-ischemic brain injury. Free Radic Biol Med 2018; 124:517-524. [PMID: 30037775 PMCID: PMC6389362 DOI: 10.1016/j.freeradbiomed.2018.06.040] [Citation(s) in RCA: 38] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/27/2018] [Revised: 06/28/2018] [Accepted: 06/29/2018] [Indexed: 02/02/2023]
Abstract
BACKGROUND Establishing sustained reoxygenation/reperfusion ensures not only the recovery, but may initiate a reperfusion injury in which oxidative stress plays a major role. This study offers the mechanism and this mechanism-specific therapeutic strategy against excessive release of reactive oxygen species (ROS) associated with reperfusion-driven recovery of mitochondrial metabolism. AIMS AND METHODS In neonatal mice subjected to cerebral hypoxia-ischaemia (HI) and reperfusion, we examined conformational changes and activity of mitochondrial complex I with and without post-HI administration of S-nitrosating agent, MitoSNO. Assessment of mitochondrial ROS production, oxidative brain damage, neuropathological and neurofunctional outcomes were used to define neuroprotective strength of MitoSNO. A specificity of reperfusion-driven mitochondrial ROS production to conformational changes in complex I was examined in-vitro. RESULTS HI deactivated complex I, changing its conformation from active form (A) into the catalytically dormant, de-active form (D). Reperfusion rapidly converted the D-form into the A-form and increased ROS generation. Administration of MitoSNO at the onset of reperfusion, decelerated D→A transition of complex I, attenuated oxidative stress, and significantly improved neurological recovery. In cultured neurons, after simulated ischaemia-reperfusion injury, MitoSNO significantly reduced ROS generation and neuronal mortality. In isolated mitochondria subjected to anoxia-reoxygenation, MitoSNO restricted ROS release during D→A transitions. CONCLUSION Rapid D→A conformation in response to reperfusion reactivates complex I. This is essential not only for metabolic recovery, but also contributes to excessive release of mitochondrial ROS and reperfusion injury. We propose that the initiation of reperfusion should be followed by pharmacologically-controlled gradual reactivation of complex I.
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Affiliation(s)
- Minso Kim
- Department of Pediatrics, Division of Neonatology, Columbia University, NY, USA
| | - Anna Stepanova
- Department of Pediatrics, Division of Neonatology, Columbia University, NY, USA; School of Biological Sciences, Queen's University Belfast, UK
| | - Zoya Niatsetskaya
- Department of Pediatrics, Division of Neonatology, Columbia University, NY, USA
| | - Sergey Sosunov
- Department of Pediatrics, Division of Neonatology, Columbia University, NY, USA
| | - Sabine Arndt
- MRC Mitochondrial Biology Unit, University of Cambridge, Cambridge, UK
| | - Michael P Murphy
- MRC Mitochondrial Biology Unit, University of Cambridge, Cambridge, UK
| | - Alexander Galkin
- Department of Pediatrics, Division of Neonatology, Columbia University, NY, USA; School of Biological Sciences, Queen's University Belfast, UK.
| | - Vadim S Ten
- Department of Pediatrics, Division of Neonatology, Columbia University, NY, USA.
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Perinatal Asphyxia and Brain Development: Mitochondrial Damage Without Anatomical or Cellular Losses. Mol Neurobiol 2018; 55:8668-8679. [PMID: 29582399 DOI: 10.1007/s12035-018-1019-7] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2018] [Accepted: 03/16/2018] [Indexed: 01/05/2023]
Abstract
Perinatal asphyxia remains a significant cause of neonatal mortality and is associated with long-term neurodegenerative disorders. In the present study, we evaluated cellular and subcellular damages to brain development in a model of mild perinatal asphyxia. Survival rate in the experimental group was 67%. One hour after the insult, intraperitoneally injected Evans blue could be detected in the fetuses' brains, indicating disruption of the blood-brain barrier. Although brain mass and absolute cell numbers (neurons and non-neurons) were not reduced after perinatal asphyxia immediately and in late brain development, subcellular alterations were detected. Cortical oxygen consumption increased immediately after asphyxia, and remained high up to 7 days, returning to normal levels after 14 days. We observed an increased resistance to mitochondrial membrane permeability transition, and calcium buffering capacity in asphyxiated animals from birth to 14 days after the insult. In contrast to ex vivo data, mitochondrial oxygen consumption in primary cell cultures of neurons and astrocytes was not altered after 1% hypoxia. Taken together, our results demonstrate that although newborns were viable and apparently healthy, brain development is subcellularly altered by perinatal asphyxia. Our findings place the neonate brain mitochondria as a potential target for therapeutic protective interventions.
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24
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Galinsky R, Davidson JO, Dean JM, Green CR, Bennet L, Gunn AJ. Glia and hemichannels: key mediators of perinatal encephalopathy. Neural Regen Res 2018; 13:181-189. [PMID: 29557357 PMCID: PMC5879879 DOI: 10.4103/1673-5374.226378] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Perinatal encephalopathy remains a major cause of disability, such as cerebral palsy. Therapeutic hypothermia is now well established to partially reduce risk of disability in late preterm/term infants. However, new and complementary therapeutic targets are needed to further improve outcomes. There is increasing evidence that glia play a key role in neural damage after hypoxia-ischemia and infection/inflammation. In this review, we discuss the role of astrocytic gap junction (connexin) hemichannels in the spread of neural injury after hypoxia-ischemia and/or infection/inflammation. Potential mechanisms of hemichannel mediated injury likely involve impaired intracellular calcium handling, loss of blood-brain barrier integrity and release of adenosine triphosphate (ATP) resulting in over-activation of purinergic receptors. We propose the hypothesis that inflammation-induced opening of connexin hemichannels is a key regulating event that initiates a vicious cycle of excessive ATP release, which in turn propagates activation of purinergic receptors on microglia and astrocytes. This suggests that developing new neuroprotective strategies for preterm infants will benefit from a detailed understanding of glial and connexin hemichannel responses.
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Affiliation(s)
- Robert Galinsky
- Department of Physiology, University of Auckland, Auckland, New Zealand; The Ritchie Centre, Hudson Institute of Medical Research, Victoria, Australia
| | - Joanne O Davidson
- Department of Physiology, University of Auckland, Auckland, New Zealand
| | - Justin M Dean
- Department of Physiology, University of Auckland, Auckland, New Zealand
| | - Colin R Green
- Department of Ophthalmology, University of Auckland, Auckland, New Zealand
| | - 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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25
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Thornton C, Jones A, Nair S, Aabdien A, Mallard C, Hagberg H. Mitochondrial dynamics, mitophagy and biogenesis in neonatal hypoxic-ischaemic brain injury. FEBS Lett 2017; 592:812-830. [PMID: 29265370 DOI: 10.1002/1873-3468.12943] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2017] [Revised: 11/22/2017] [Accepted: 12/11/2017] [Indexed: 12/13/2022]
Abstract
Hypoxic-ischaemic encephalopathy, resulting from asphyxia during birth, affects 2-3 in every 1000 term infants and depending on severity, brings about life-changing neurological consequences or death. This hypoxic-ischaemia (HI) results in a delayed neural energy failure during which the majority of brain injury occurs. Currently, there are limited treatment options and additional therapies are urgently required. Mitochondrial dysfunction acts as a focal point in injury development in the immature brain. Not only do mitochondria become permeabilised, but recent findings implicate perturbations in mitochondrial dynamics (fission, fusion), mitophagy and biogenesis. Mitoprotective therapies may therefore offer a new avenue of intervention for babies who suffer lifelong disabilities due to birth asphyxia.
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Affiliation(s)
- Claire Thornton
- Perinatal Brain Injury Group, Division of Imaging Sciences and Biomedical Engineering, Centre for the Developing Brain, King's College London, King's Health Partners, St. Thomas' Hospital, London, UK
| | - Adam Jones
- Perinatal Brain Injury Group, Division of Imaging Sciences and Biomedical Engineering, Centre for the Developing Brain, King's College London, King's Health Partners, St. Thomas' Hospital, London, UK
| | - Syam Nair
- Perinatal Center, Department of Physiology, Institute of Physiology and Neuroscience, Sahlgrenska Academy, University of Gothenburg, Sweden
| | - Afra Aabdien
- Perinatal Brain Injury Group, Division of Imaging Sciences and Biomedical Engineering, Centre for the Developing Brain, King's College London, King's Health Partners, St. Thomas' Hospital, London, UK
| | - Carina Mallard
- Perinatal Center, Department of Physiology, Institute of Physiology and Neuroscience, Sahlgrenska Academy, University of Gothenburg, Sweden
| | - Henrik Hagberg
- Perinatal Brain Injury Group, Division of Imaging Sciences and Biomedical Engineering, Centre for the Developing Brain, King's College London, King's Health Partners, St. Thomas' Hospital, London, UK.,Perinatal Center, Department of Clinical Sciences & Physiology and Neuroscience, Sahlgrenska Academy, University of Gothenburg, Sweden
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26
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Oxidative stress and endoplasmic reticulum (ER) stress in the development of neonatal hypoxic-ischaemic brain injury. Biochem Soc Trans 2017; 45:1067-1076. [PMID: 28939695 PMCID: PMC5652227 DOI: 10.1042/bst20170017] [Citation(s) in RCA: 46] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2017] [Revised: 08/09/2017] [Accepted: 08/11/2017] [Indexed: 02/06/2023]
Abstract
Birth asphyxia in term neonates affects 1–2/1000 live births and results in the development of hypoxic–ischaemic encephalopathy with devastating life-long consequences. The majority of neuronal cell death occurs with a delay, providing the potential of a treatment window within which to act. Currently, treatment options are limited to therapeutic hypothermia which is not universally successful. To identify new interventions, we need to understand the molecular mechanisms underlying the injury. Here, we provide an overview of the contribution of both oxidative stress and endoplasmic reticulum stress in the development of neonatal brain injury and identify current preclinical therapeutic strategies.
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27
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Thornton C, Leaw B, Mallard C, Nair S, Jinnai M, Hagberg H. Cell Death in the Developing Brain after Hypoxia-Ischemia. Front Cell Neurosci 2017; 11:248. [PMID: 28878624 PMCID: PMC5572386 DOI: 10.3389/fncel.2017.00248] [Citation(s) in RCA: 110] [Impact Index Per Article: 15.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2017] [Accepted: 08/07/2017] [Indexed: 01/11/2023] Open
Abstract
Perinatal insults such as hypoxia–ischemia induces secondary brain injury. In order to develop the next generation of neuroprotective therapies, we urgently need to understand the underlying molecular mechanisms leading to cell death. The cell death mechanisms have been shown to be quite different in the developing brain compared to that in the adult. The aim of this review is update on what cell death mechanisms that are operating particularly in the setting of the developing CNS. In response to mild stress stimuli a number of compensatory mechanisms will be activated, most often leading to cell survival. Moderate-to-severe insults trigger regulated cell death. Depending on several factors such as the metabolic situation, cell type, nature of the stress stimulus, and which intracellular organelle(s) are affected, the cell undergoes apoptosis (caspase activation) triggered by BAX dependent mitochondrial permeabilzation, necroptosis (mixed lineage kinase domain-like activation), necrosis (via opening of the mitochondrial permeability transition pore), autophagic cell death (autophagy/Na+, K+-ATPase), or parthanatos (poly(ADP-ribose) polymerase 1, apoptosis-inducing factor). Severe insults cause accidental cell death that cannot be modulated genetically or by pharmacologic means. However, accidental cell death leads to the release of factors (damage-associated molecular patterns) that initiate systemic effects, as well as inflammation and (regulated) secondary brain injury in neighboring tissue. Furthermore, if one mode of cell death is inhibited, another route may step in at least in a scenario when upstream damaging factors predominate over protective responses. The provision of alternative routes through which the cell undergoes death has to be taken into account in the hunt for novel brain protective strategies.
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Affiliation(s)
- Claire Thornton
- Division of Imaging Sciences and Biomedical Engineering, Centre for the Developing Brain, King's College London, King's Health Partners, St. Thomas' HospitalLondon, United Kingdom
| | - Bryan Leaw
- The Ritchie Centre, Hudson Institute of Medical ResearchClayton, VIC, Australia
| | - Carina Mallard
- Department of Physiology, Perinatal Center, Institute of Physiology and Neuroscience, Sahlgrenska Academy, University of GothenburgGothenburg, Sweden
| | - Syam Nair
- Department of Physiology, Perinatal Center, Institute of Physiology and Neuroscience, Sahlgrenska Academy, University of GothenburgGothenburg, Sweden
| | - Masako Jinnai
- Department of Physiology, Perinatal Center, Institute of Physiology and Neuroscience, Sahlgrenska Academy, University of GothenburgGothenburg, Sweden
| | - Henrik Hagberg
- Division of Imaging Sciences and Biomedical Engineering, Centre for the Developing Brain, King's College London, King's Health Partners, St. Thomas' HospitalLondon, United Kingdom.,Department of Clinical Sciences and Physiology and Neuroscience, Perinatal Center, Sahlgrenska Academy, Gothenburg UniversityGothenburg, Sweden
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28
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Baburamani AA, Sobotka KS, Vontell R, Mallard C, Supramaniam VG, Thornton C, Hagberg H. Effect of Trp53 gene deficiency on brain injury after neonatal hypoxia-ischemia. Oncotarget 2017; 8:12081-12092. [PMID: 28076846 PMCID: PMC5355327 DOI: 10.18632/oncotarget.14518] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2016] [Accepted: 12/26/2016] [Indexed: 02/06/2023] Open
Abstract
Hypoxia-ischemia (HI) can result in permanent life-long injuries such as motor and cognitive deficits. In response to cellular stressors such as hypoxia, tumor suppressor protein p53 is activated, potently initiating apoptosis and promoting Bax-dependent mitochondrial outer membrane permeabilization. The aim of this study was to investigate the effect of Trp53 genetic inhibition on injury development in the immature brain following HI. HI (50 min or 60 min) was induced at postnatal day 9 (PND9) in Trp53 heterozygote (het) and wild type (WT) mice. Utilizing Cre-LoxP technology, CaMK2α-Cre mice were bred with Trp53-Lox mice, resulting in knockdown of Trp53 in CaMK2α neurons. HI was induced at PND12 (50 min) and PND28 (40 min). Extent of brain injury was assessed 7 days following HI. Following 50 min HI at PND9, Trp53 het mice showed protection in the posterior hippocampus and thalamus. No difference was seen between WT or Trp53 het mice following a severe, 60 min HI. Cre-Lox mice that were subjected to HI at PND12 showed no difference in injury, however we determined that neuronal specific CaMK2α-Cre recombinase activity was strongly expressed by PND28. Concomitantly, Trp53 was reduced at 6 weeks of age in KO-Lox Trp53 mice. Cre-Lox mice subjected to HI at PND28 showed no significant difference in brain injury. These data suggest that p53 has a limited contribution to the development of injury in the immature/juvenile brain following HI. Further studies are required to determine the effect of p53 on downstream targets.
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Affiliation(s)
- Ana A Baburamani
- Perinatal Brain Injury Group, Centre for the Developing Brain, Division of Imaging Sciences and Biomedical Engineering, King's College London, King's Health Partners, St. Thomas' Hospital, London, United Kingdom.,Perinatal Center, Institute of Neuroscience and Physiology, Clinical Sciences, Sahlgrenska Academy, University of Gothenburg, Sweden
| | - Kristina S Sobotka
- Perinatal Center, Institute of Neuroscience and Physiology, Clinical Sciences, Sahlgrenska Academy, University of Gothenburg, Sweden
| | - Regina Vontell
- Perinatal Brain Injury Group, Centre for the Developing Brain, Division of Imaging Sciences and Biomedical Engineering, King's College London, King's Health Partners, St. Thomas' Hospital, London, United Kingdom
| | - Carina Mallard
- Perinatal Center, Institute of Neuroscience and Physiology, Clinical Sciences, Sahlgrenska Academy, University of Gothenburg, Sweden
| | - Veena G Supramaniam
- Perinatal Brain Injury Group, Centre for the Developing Brain, Division of Imaging Sciences and Biomedical Engineering, King's College London, King's Health Partners, St. Thomas' Hospital, London, United Kingdom
| | - Claire Thornton
- Perinatal Brain Injury Group, Centre for the Developing Brain, Division of Imaging Sciences and Biomedical Engineering, King's College London, King's Health Partners, St. Thomas' Hospital, London, United Kingdom
| | - Henrik Hagberg
- Perinatal Brain Injury Group, Centre for the Developing Brain, Division of Imaging Sciences and Biomedical Engineering, King's College London, King's Health Partners, St. Thomas' Hospital, London, United Kingdom.,Perinatal Center, Institute of Neuroscience and Physiology, Clinical Sciences, Sahlgrenska Academy, University of Gothenburg, Sweden
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29
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Galinsky R, Davidson JO, Lear CA, Bennet L, Green CR, Gunn AJ. Connexin hemichannel blockade improves survival of striatal GABA-ergic neurons after global cerebral ischaemia in term-equivalent fetal sheep. Sci Rep 2017; 7:6304. [PMID: 28740229 PMCID: PMC5524909 DOI: 10.1038/s41598-017-06683-1] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2017] [Accepted: 06/15/2017] [Indexed: 11/17/2022] Open
Abstract
Basal ganglia injury at term remains a major cause of disability, such as cerebral palsy. In this study we tested the hypotheses that blockade of astrocytic connexin hemichannels with a mimetic peptide would improve survival of striatal phenotypic neurons after global cerebral ischaemia in term-equivalent fetal sheep, and that neuronal survival would be associated with electrophysiological recovery. Fetal sheep (0.85 gestation) were randomly assigned to receive a short or long (1 or 25 h) intracerebroventricular infusion of a mimetic peptide or vehicle, starting 90 minutes after 30 minutes of cerebral ischaemia. Sheep were killed 7 days after ischaemia. Cerebral ischaemia was associated with reduced numbers of calbindin-28k, calretinin, parvalbumin and GAD positive striatal neurons (P < 0.05 ischaemia + vehicle, n = 6 vs. sham ischaemia, n = 6) but not ChAT or nNOS positive neurons. Short infusion of peptide (n = 6) did not significantly improve survival of any striatal phenotype. Long infusion of peptide (n = 6) was associated with increased survival of calbindin-28k, calretinin, parvalbumin and GAD positive neurons (P < 0.05 vs. ischaemia + vehicle). Neurophysiological recovery was associated with improved survival of calbindin-28k, calretinin and parvalbumin positive striatal neurons (P < 0.05 for all). In conclusion, connexin hemichannel blockade after cerebral ischaemia in term-equivalent fetal sheep improves survival of striatal GABA-ergic neurons.
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Affiliation(s)
- Robert Galinsky
- Department of Physiology, The University of Auckland, Auckland, New Zealand.,The Ritchie Centre, Hudson Institute of Medical Research, Victoria, Australia
| | - Joanne O Davidson
- Department of Physiology, The University of Auckland, Auckland, New Zealand
| | - Christopher A Lear
- Department of Physiology, The University of Auckland, Auckland, New Zealand
| | - Laura Bennet
- Department of Physiology, The University of Auckland, Auckland, New Zealand
| | - Colin R Green
- Department of Ophthalmology, The University of Auckland, Auckland, New Zealand
| | - Alistair J Gunn
- Department of Physiology, The University of Auckland, Auckland, New Zealand.
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30
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Effect of Hypoxic Injury in Mood Disorder. Neural Plast 2017; 2017:6986983. [PMID: 28717522 PMCID: PMC5498932 DOI: 10.1155/2017/6986983] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2017] [Revised: 05/26/2017] [Accepted: 06/06/2017] [Indexed: 12/12/2022] Open
Abstract
Hypoxemia is a common complication of the diseases associated with the central nervous system, and neurons are highly sensitive to the availability of oxygen. Neuroplasticity is an important property of the neural system controlling breathing, memory, and cognitive ability. However, the underlying mechanism has not yet been clearly elucidated. In recent years, several pieces of evidence have highlighted the effect of hypoxic injury on neuronal plasticity in the pathogenesis and treatment of mood disorder. Therefore, the present study reviewed the relevant articles regarding hypoxic injury and neuronal plasticity and discussed the pathological changes and physiological functions of neurons in hypoxemia in order to provide a translational perspective to the relevance of hypoxic injury and mood disorder.
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31
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Riew TR, Shin YJ, Kim HL, Cho JM, Pak HJ, Lee MY. Spatiotemporal Progression of Microcalcification in the Hippocampal CA1 Region following Transient Forebrain Ischemia in Rats: An Ultrastructural Study. PLoS One 2016; 11:e0159229. [PMID: 27414398 PMCID: PMC4945069 DOI: 10.1371/journal.pone.0159229] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2016] [Accepted: 06/29/2016] [Indexed: 11/19/2022] Open
Abstract
Calcification in areas of neuronal degeneration is a common finding in several neuropathological disorders including ischemic insults. Here, we performed a detailed examination of the onset and spatiotemporal profile of calcification in the CA1 region of the hippocampus, where neuronal death has been observed after transient forebrain ischemia. Histopathological examinations showed very little alizarin red staining in the CA1 pyramidal cell layer until day 28 after reperfusion, while prominent alizarin red staining was detected in CA1 dendritic subfields, particularly in the stratum radiatum, by 14 days after reperfusion. Electron microscopy using the osmium/potassium dichromate method and electron probe microanalysis revealed selective calcium deposits within the mitochondria of degenerating dendrites at as early as 7 days after reperfusion, with subsequent complete mineralization occurring throughout the dendrites, which then coalesced to form larger mineral conglomerates with the adjacent calcifying neurites by 14 days after reperfusion. Large calcifying deposits were frequently observed at 28 days after reperfusion, when they were closely associated with or completely engulfed by astrocytes. In contrast, no prominent calcification was observed in the somata of CA1 pyramidal neurons showing the characteristic features of necrotic cell death after ischemia, although what appeared to be calcified mitochondria were noted in some degenerated neurons that became dark and condensed. Thus, our data indicate that intrahippocampal calcification after ischemic insults initially occurs within the mitochondria of degenerating dendrites, which leads to the extensive calcification that is associated with ischemic injuries. These findings suggest that in degenerating neurons, the calcified mitochondria in the dendrites, rather than in the somata, may serve as the nidus for further calcium precipitation in the ischemic hippocampus.
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Affiliation(s)
- Tae-Ryong Riew
- Department of Anatomy, Catholic Neuroscience Institute, Cell Death Disease Research Center, College of Medicine, The Catholic University of Korea, 137-701, Seoul, Korea
| | - Yoo-Jin Shin
- Department of Anatomy, Catholic Neuroscience Institute, Cell Death Disease Research Center, College of Medicine, The Catholic University of Korea, 137-701, Seoul, Korea
| | - Hong Lim Kim
- Integrative Research Support Center, Laboratory of Electron Microscope, College of Medicine, The Catholic University of Korea, Seoul, Korea, 137-701, Seoul, Korea
| | - Jeong Min Cho
- Department of Anatomy, Catholic Neuroscience Institute, Cell Death Disease Research Center, College of Medicine, The Catholic University of Korea, 137-701, Seoul, Korea
| | - Ha-Jin Pak
- Department of Anatomy, Catholic Neuroscience Institute, Cell Death Disease Research Center, College of Medicine, The Catholic University of Korea, 137-701, Seoul, Korea
| | - Mun-Yong Lee
- Department of Anatomy, Catholic Neuroscience Institute, Cell Death Disease Research Center, College of Medicine, The Catholic University of Korea, 137-701, Seoul, Korea
- * E-mail:
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32
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Plasticity in the Neonatal Brain following Hypoxic-Ischaemic Injury. Neural Plast 2016; 2016:4901014. [PMID: 27047695 PMCID: PMC4800097 DOI: 10.1155/2016/4901014] [Citation(s) in RCA: 122] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2015] [Revised: 01/12/2016] [Accepted: 02/07/2016] [Indexed: 12/03/2022] Open
Abstract
Hypoxic-ischaemic damage to the developing brain is a leading cause of child death, with high mortality and morbidity, including cerebral palsy, epilepsy, and cognitive disabilities. The developmental stage of the brain and the severity of the insult influence the selective regional vulnerability and the subsequent clinical manifestations. The increased susceptibility to hypoxia-ischaemia (HI) of periventricular white matter in preterm infants predisposes the immature brain to motor, cognitive, and sensory deficits, with cognitive impairment associated with earlier gestational age. In term infants HI causes selective damage to sensorimotor cortex, basal ganglia, thalamus, and brain stem. Even though the immature brain is more malleable to external stimuli compared to the adult one, a hypoxic-ischaemic event to the neonate interrupts the shaping of central motor pathways and can affect normal developmental plasticity through altering neurotransmission, changes in cellular signalling, neural connectivity and function, wrong targeted innervation, and interruption of developmental apoptosis. Models of neonatal HI demonstrate three morphologically different types of cell death, that is, apoptosis, necrosis, and autophagy, which crosstalk and can exist as a continuum in the same cell. In the present review we discuss the mechanisms of HI injury to the immature brain and the way they affect plasticity.
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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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34
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Kim HL, Lee MY, Shin YJ, Song DW, Park J, Chang BS, Lee JH. Increased Expression of Osteopontin in the Degenerating Striatum of Rats Treated with Mitochondrial Toxin 3-Nitropropionic Acid: A Light and Electron Microscopy Study. Acta Histochem Cytochem 2015; 48:135-43. [PMID: 26633905 PMCID: PMC4652028 DOI: 10.1267/ahc.15010] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2015] [Accepted: 09/04/2015] [Indexed: 12/16/2022] Open
Abstract
The mycotoxin 3-nitropropionic acid (3NP) is an irreversible inhibitor that induces neuronal damage by inhibiting mitochondrial complex II. Neurodegeneration induced by 3NP, which is preferentially induced in the striatum, is caused by an excess influx and accumulation of calcium in mitochondria. Osteopontin (OPN) is a glycosylated phosphoprotein and plays a role in the regulation of calcium precipitation in the injured brain. The present study was designed to examine whether induction of OPN protein is implicated in the pathogenesis of 3NP-induced striatal neurodegeneration. We observed overlapping regional expression of OPN, the neurodegeneration marker Fluoro-Jade B, and the microglial marker ionized calcium-binding adaptor molecule 1 (Iba1) in the 3NP-lesioned striatum. OPN expression was closely associated with the mitochondrial marker NADH dehydrogenase (ubiquinone) flavoprotein 2 in the damaged striatum. In addition, immunoelectron microscopy demonstrated that OPN protein was specifically localized to the inner membrane and matrix of the mitochondria in degenerating striatal neurons, and cell fragments containing OPN-labeled mitochondria were also present within activated brain macrophages. Thus, our study revealed that OPN expression is associated with mitochondrial dysfunction produced by 3NP-induced alteration of mitochondrial calcium homeostasis, suggesting that OPN is involved in the pathogenesis of striatal degeneration by 3NP administration.
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Affiliation(s)
- Hong-Lim Kim
- Department of Veterinary Anatomy, College of Veterinary Medicine, Konkuk University
- Integrative Research Support Center, College of Medicine, Catholic University
| | - Mun-Yong Lee
- Department of Anatomy, College of Medicine, Catholic University
| | - Yoo-Jin Shin
- Department of Anatomy, College of Medicine, Catholic University
| | - Doo-Won Song
- Department of Veterinary Internal Medicine, College of Veterinary Medicine, Konkuk University
| | - Jieun Park
- Integrative Research Support Center, College of Medicine, Catholic University
| | | | - Jong-Hwan Lee
- Department of Veterinary Anatomy, College of Veterinary Medicine, Konkuk University
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Perinatal brain damage: The term infant. Neurobiol Dis 2015; 92:102-12. [PMID: 26409031 PMCID: PMC4915441 DOI: 10.1016/j.nbd.2015.09.011] [Citation(s) in RCA: 70] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2015] [Revised: 08/27/2015] [Accepted: 09/22/2015] [Indexed: 12/21/2022] Open
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Mitochondrial Optic Atrophy (OPA) 1 Processing Is Altered in Response to Neonatal Hypoxic-Ischemic Brain Injury. Int J Mol Sci 2015; 16:22509-26. [PMID: 26393574 PMCID: PMC4613321 DOI: 10.3390/ijms160922509] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2015] [Revised: 08/26/2015] [Accepted: 09/11/2015] [Indexed: 01/02/2023] Open
Abstract
Perturbation of mitochondrial function and subsequent induction of cell death pathways are key hallmarks in neonatal hypoxic-ischemic (HI) injury, both in animal models and in term infants. Mitoprotective therapies therefore offer a new avenue for intervention for the babies who suffer life-long disabilities as a result of birth asphyxia. Here we show that after oxygen-glucose deprivation in primary neurons or in a mouse model of HI, mitochondrial protein homeostasis is altered, manifesting as a change in mitochondrial morphology and functional impairment. Furthermore we find that the mitochondrial fusion and cristae regulatory protein, OPA1, is aberrantly cleaved to shorter forms. OPA1 cleavage is normally regulated by a balanced action of the proteases Yme1L and Oma1. However, in primary neurons or after HI in vivo, protein expression of YmelL is also reduced, whereas no change is observed in Oma1 expression. Our data strongly suggest that alterations in mitochondria-shaping proteins are an early event in the pathogenesis of neonatal HI injury.
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Tataranno ML, Perrone S, Buonocore G. Plasma Biomarkers of Oxidative Stress in Neonatal Brain Injury. Clin Perinatol 2015; 42:529-39. [PMID: 26250915 DOI: 10.1016/j.clp.2015.04.011] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Perinatal encephalopathy is a leading cause of lifelong disability. Increasing evidence indicates that the pathogenesis of perinatal brain damage is much more complex than originally thought, with multiple pathways involved. An important role of oxidative stress (OS) in the pathogenesis of brain injury is recognized for preterm and term infants. This article examines potential reliable and specific OS biomarkers that can be used in premature and term infants for the early detection and follow-up of the most common neonatal brain injuries, such as hypoxic-ischemic encephalopathy, intraventricular hemorrhage, and periventricular leukomalacia. The next step will be to explore the correlation between brain-specific OS biomarkers and functional brain outcomes.
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Affiliation(s)
- Maria Luisa Tataranno
- Department of Molecular and Developmental Medicine, University of Siena, Via Banchi di Sotto, 55, 53100 Siena, Italy
| | - Serafina Perrone
- Department of Molecular and Developmental Medicine, University of Siena, Via Banchi di Sotto, 55, 53100 Siena, Italy.
| | - Giuseppe Buonocore
- Department of Molecular and Developmental Medicine, University of Siena, Via Banchi di Sotto, 55, 53100 Siena, Italy
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Affiliation(s)
- Sophia Häfner
- University of Copenhagen, BRIC Biotech Research & Innovation Centre, Lund Group, 2200 Copenhagen, Denmark.
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Riew TR, Kim HL, Shin YJ, Park JH, Pak HJ, Lee MY. Ultrastructural investigation of microcalcification and the role of oxygen-glucose deprivation in cultured rat hippocampal slices. Brain Res 2015; 1622:430-42. [PMID: 26188662 DOI: 10.1016/j.brainres.2015.06.048] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2015] [Revised: 06/24/2015] [Accepted: 06/25/2015] [Indexed: 01/09/2023]
Abstract
Intracellular calcium accumulation is associated with cell death in several neuropathological disorders including brain ischemia, but the exact mechanisms of calcification need to be clarified. We used organotypic hippocampal slice culture - cultures subjected to oxygen-glucose deprivation (OGD) mimicking the in vivo situation to investigate the events underlying ectopic calcification. Alizarin red staining indicating calcium deposition was observed in the cornu ammonis (CA)1 and dentate gyrus regions in control hippocampal slices despite no specific labeling for cell death markers. Electron microscopy using the osmium/potassium dichromate method revealed scattered degenerated cells throughout the normally appearing CA1 region. They contained electron-dense precipitates within mitochondria, and electron probe microanalysis confirmed that they were calcifying mitochondria. Selective calcium deposition was noted within, but not beyond, mitochondria in these mineralized cells. They showed ultrastructural features of non-necrotic, non-apoptotic cell death and retained their compact ultrastructure, even after the majority of mitochondria were calcified. Unexpectedly, no intracellular calcification was noted in necrotic CA1 pyramidal cells after OGD, and there was no progression of calcification in OGD-lesioned slices. In addition, mineralized cells in both control and OGD-lesioned slices were closely associated with or completely engulfed by astrocytes but not microglia. These astrocytes were laden with heterogeneous cytoplasmic inclusions that appeared to be related with their phagocytic activity. These data demonstrate that microcalcification specifically associated with mitochondria might lead to a novel type of cell death and suggest that astrocytes may be involved in the phagocytosis of these mineralized cells and possibly in the regulation of ectopic calcification.
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Affiliation(s)
- Tae-Ryong Riew
- Department of Anatomy, Catholic Neuroscience Institute, College of Medicine, The Catholic University of Korea, 137-701 Seoul, Korea
| | - Hong Lim Kim
- Integrative Research Support Center, Laboratory of Electron Microscope, College of Medicine, The Catholic University of Korea, Seoul, Korea
| | - Yoo-Jin Shin
- Department of Anatomy, Catholic Neuroscience Institute, College of Medicine, The Catholic University of Korea, 137-701 Seoul, Korea
| | - Joo-Hee Park
- Department of Anatomy, Catholic Neuroscience Institute, College of Medicine, The Catholic University of Korea, 137-701 Seoul, Korea
| | - Ha-Jin Pak
- Department of Anatomy, Catholic Neuroscience Institute, College of Medicine, The Catholic University of Korea, 137-701 Seoul, Korea
| | - Mun-Yong Lee
- Department of Anatomy, Catholic Neuroscience Institute, College of Medicine, The Catholic University of Korea, 137-701 Seoul, Korea.
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Thornton C, Hagberg H. Role of mitochondria in apoptotic and necroptotic cell death in the developing brain. Clin Chim Acta 2015; 451:35-8. [PMID: 25661091 PMCID: PMC4661434 DOI: 10.1016/j.cca.2015.01.026] [Citation(s) in RCA: 73] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2014] [Revised: 01/28/2015] [Accepted: 01/28/2015] [Indexed: 11/26/2022]
Abstract
Hypoxic–ischemic encephalopathy induces secondary brain injury characterized by delayed energy failure. Currently, therapeutic hypothermia is the sole treatment available after severe intrapartum asphyxia in babies and acts to attenuate secondary loss of high energy phosphates improving both short- and long-term outcome. In order to develop the next generation of neuroprotective therapies, we urgently need to understand the underlying molecular mechanisms leading to cell death. Hypoxia–ischemia creates a toxic intracellular environment including accumulation of reactive oxygen/nitrosative species and intracellular calcium after the insult, inducing mitochondrial impairment. More specifically mitochondrial respiration is suppressed and calcium signaling is dysregulated. At a certain threshold, Bax-dependent mitochondrial permeabilization will occur leading to activation of caspase-dependent and apoptosis-inducing factor-dependent apoptotic cell death. In addition, hypoxia–ischemia induces inflammation, which leads to the release of TNF-α, TRAIL, TWEAK, FasL and Toll-like receptor agonists that will activate death receptors on neurons and oligodendroglia. Death receptors trigger apoptotic death via caspase-8 and necroptotic cell death through formation of the necrosome (composed of RIP1, RIP3 and MLKL), both of which converge at the mitochondria. Hypoxic-ischemic encephalopathy induces secondary brain injury characterized by delayed energy failure and excitotoxicity. Hypoxia-ischemia triggers accumulation of reactive oxygen species andintracellular calcium, which induces mitochondrial dysfunction. Mitochondrial impairment can cause Bax-dependent mitochondrial permeabilization, which triggers release of pro-apoptotic proteins and cell death. During the recovery phase, Inflammation is produced leading to death receptor activation and induction of necroptosis.
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Affiliation(s)
- Claire Thornton
- Centre for the Developing Brain, Division of Imaging Sciences and Biomedical Engineering, King's College London, King's Health Partners, St. Thomas' Hospital, London SE1 7EH, United Kingdom
| | - Henrik Hagberg
- Centre for the Developing Brain, Division of Imaging Sciences and Biomedical Engineering, King's College London, King's Health Partners, St. Thomas' Hospital, London SE1 7EH, United Kingdom; Perinatal Center, Department of Clinical Sciences & Physiology and Neuroscience, Sahlgrenska Academy, Gothenburg University, Sweden
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Hsu YC, Chang YC, Lin YC, Sze CI, Huang CC, Ho CJ. Cerebral microvascular damage occurs early after hypoxia-ischemia via nNOS activation in the neonatal brain. J Cereb Blood Flow Metab 2014; 34:668-76. [PMID: 24398931 PMCID: PMC3982088 DOI: 10.1038/jcbfm.2013.244] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/13/2013] [Accepted: 12/16/2013] [Indexed: 11/09/2022]
Abstract
Microvascular injury early after hypoxic ischemia (HI) may contribute to neonatal brain damage. N-methyl-D-aspartate receptor overstimulation activates neuronal nitric oxide synthases (nNOS). We hypothesized that microvascular damage occurs early post-HI via nNOS activation and contributes to brain injury. Postpartum day-7 rat pups were treated with 7-nitroindazole (7-NI) or aminoguanidine (AG) before or after HI. Electron microscopy was performed to measure neuronal and endothelial cell damage. There were vascular lumen narrowing at 1 hour, pyknotic neurons at 3 hours, and extensive neuronal damage and loss of vessels at 24 hours post HI. Early after reoxygenation, there were neurons with heterochromatic chromatin and endothelial cells with enlarged nuclei occluding the lumen. There was also increased 3-nitrotyrosin in the microvessels and decreased cerebral blood perfusion. 7-NI and AG treatment before hypoxia provided complete and partial neuroprotection, respectively. Early post-reoxygenation, the AG group showed significantly increased microvascular nitrosative stress, microvascular interruptions, swollen nuclei that narrowed the vascular lumen, and decreased cerebral perfusion. The 7-NI group showed significantly decreased microvascular nitrosative stress, patent vascular lumen, and increased cerebral perfusion. Our results indicate that microvascular damage occurs early and progressively post HI. Neuronal nitric oxide synthases activation contributes to microvascular damage and decreased cerebral perfusion early after reoxygenation and worsens brain damage.
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Affiliation(s)
- Yi-Ching Hsu
- Institute of Basic Medical Sciences, National Cheng Kung University Medical College, Tainan City, Taiwan
| | - Ying-Chao Chang
- Department of Pediatrics, Chang Gung Kaohsiung Medical Center, Chang Gung University College of Medicine, Kaohsiung City, Taiwan
| | - Yung-Chieh Lin
- 1] Institute of Clinical Medicine, National Cheng Kung University Medical College, Tainan City, Taiwan [2] Department of Pediatrics, National Cheng Kung University Hospital, Tainan City, Taiwan
| | - Chun-I Sze
- Institute of Cell Biology and Anatomy, National Cheng Kung University Medical College, Tainan City, Taiwan
| | - Chao-Ching Huang
- 1] Department of Pediatrics, National Cheng Kung University Hospital, Tainan City, Taiwan [2] Department of Pediatrics, Taipei Medical University, College of Medicine, Taipei, Taiwan
| | - Chien-Jung Ho
- Department of Pediatrics, National Cheng Kung University Hospital, Tainan City, Taiwan
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Hagberg H, Mallard C, Rousset CI, Thornton C. Mitochondria: hub of injury responses in the developing brain. Lancet Neurol 2014; 13:217-32. [PMID: 24457191 DOI: 10.1016/s1474-4422(13)70261-8] [Citation(s) in RCA: 133] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Progress in the field of mitochondrial biology in the past few years has shown that mitochondrial activities go beyond bioenergetics. These new aspects of mitochondrial physiology and pathophysiology have important implications for the immature brain. A picture emerges in which mitochondrial biogenesis, mitophagy, migration, and morphogenesis are crucial for brain development and synaptic pruning, and play a part in recovery after acute insults. Mitochondria also affect brain susceptibility to injury, and mitochondria-directed interventions can make the immature brain highly resistant to acute injury. Finally, the mitochondrion is a platform for innate immunity, contributes to inflammation in response to infection and acute damage, and participates in antiviral and antibacterial defence. Understanding of these new aspects of mitochondrial function will provide insights into brain development and neurological disease, and enable discovery and development of new strategies for treatment.
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Affiliation(s)
- Henrik Hagberg
- Centre for the Developing Brain, Perinatal Imaging & Health, King's College London, St Thomas' Hospital, London, UK; Perinatal Center, Departments of Clinical Sciences and Physiology & Neurosciences, Sahlgrenska Academy, Sahlgrenska University Hospital, Gothenburg, Sweden.
| | - Carina Mallard
- Perinatal Center, Departments of Clinical Sciences and Physiology & Neurosciences, Sahlgrenska Academy, Sahlgrenska University Hospital, Gothenburg, Sweden
| | - Catherine I Rousset
- Centre for the Developing Brain, Perinatal Imaging & Health, King's College London, St Thomas' Hospital, London, UK
| | - Claire Thornton
- Centre for the Developing Brain, Perinatal Imaging & Health, King's College London, St Thomas' Hospital, London, UK
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Wassink G, Gunn ER, Drury PP, Bennet L, Gunn AJ. The mechanisms and treatment of asphyxial encephalopathy. Front Neurosci 2014; 8:40. [PMID: 24578682 PMCID: PMC3936504 DOI: 10.3389/fnins.2014.00040] [Citation(s) in RCA: 136] [Impact Index Per Article: 13.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2013] [Accepted: 02/12/2014] [Indexed: 11/13/2022] Open
Abstract
Acute post-asphyxial encephalopathy occurring around the time of birth remains a major cause of death and disability. The recent seminal insight that allows active neuroprotective treatment is that even after profound asphyxia (the “primary” phase), many brain cells show initial recovery from the insult during a short “latent” phase, typically lasting approximately 6 h, only to die hours to days later after a “secondary” deterioration characterized by seizures, cytotoxic edema, and progressive failure of cerebral oxidative metabolism. Although many of these secondary processes are potentially injurious, they appear to be primarily epiphenomena of the “execution” phase of cell death. Animal and human studies designed around this conceptual framework have shown that moderate cerebral hypothermia initiated as early as possible but before the onset of secondary deterioration, and continued for a sufficient duration to allow the secondary deterioration to resolve, has been associated with potent, long-lasting neuroprotection. Recent clinical trials show that while therapeutic hypothermia significantly reduces morbidity and mortality, many babies still die or survive with disabilities. The challenge for the future is to find ways of improving the effectiveness of treatment. In this review, we will dissect the known mechanisms of hypoxic-ischemic brain injury in relation to the known effects of hypothermic neuroprotection.
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Affiliation(s)
- Guido Wassink
- Fetal Physiology and Neuroscience Team, Department of Physiology, Faculty of Medical and Health Sciences, University of Auckland Auckland, New Zealand
| | - Eleanor R Gunn
- Fetal Physiology and Neuroscience Team, Department of Physiology, Faculty of Medical and Health Sciences, University of Auckland Auckland, New Zealand
| | - Paul P Drury
- Fetal Physiology and Neuroscience Team, Department of Physiology, Faculty of Medical and Health Sciences, University of Auckland Auckland, New Zealand
| | - Laura Bennet
- Fetal Physiology and Neuroscience Team, Department of Physiology, Faculty of Medical and Health Sciences, University of Auckland Auckland, New Zealand
| | - Alistair J Gunn
- Fetal Physiology and Neuroscience Team, Department of Physiology, Faculty of Medical and Health Sciences, University of Auckland Auckland, New Zealand
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Sharma J, Johnston MV, Hossain MA. Sex differences in mitochondrial biogenesis determine neuronal death and survival in response to oxygen glucose deprivation and reoxygenation. BMC Neurosci 2014; 15:9. [PMID: 24410996 PMCID: PMC3898007 DOI: 10.1186/1471-2202-15-9] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2013] [Accepted: 12/31/2013] [Indexed: 12/05/2022] Open
Abstract
Background Mitochondrial dysfunction has been linked to neuronal death and a wide array of neurodegenerative diseases. Previously, we have shown sex differences in mitochondria-mediated cell death pathways following hypoxia-ischemia. However, the role of mitochondrial biogenesis in hypoxic-ischemic brain injury between male vs. female has not been studied yet. Results Primary cerebellar granule neurons (CGNs), isolated from P7 male and female mice (CD-1) segregated based on visual inspection of sex, were exposed to 2 h of oxygen glucose deprivation (OGD) followed by 6–24 h of reoxygenation (Reox). Mitochondrial membrane potential (ΔΨm) and cellular ATP levels were reduced significantly in XX CGNs as compared to XY CGNs. Mitochondrial DNA (mtDNA) content was increased (>2-fold) at 2 h OGD in XY CGNs and remained increased up to 24 h of Reox compared to XX neurons and normoxia controls. The expression of mitochondrial transcription factor A (Tfam), the nuclear respiratory factor-1 (NRF-1) and the peroxisome proliferator-activated receptor γ coactivator-1α (PGC-1α), a master regulator of mitochondrial biogenesis, were up-regulated (2-fold, ***p < 0.001) in XY CGNs but slightly reduced or remained unchanged in XX neurons. Similarly, the TFAM and PGC-1α protein levels and the mitochondrial proteins HSP60 and COXIV were increased in XY neurons only. Supportively, a balanced stimulation of fusion (Mfn 1and Mfn 2) and fission (Fis 1 and Drp 1) genes and enhanced formation of donut-shaped mitochondria were observed in XY CGNs vs. XX neurons (**p < 0.01). Conclusions Our results demonstrate that OGD/Reox alters mitochondrial biogenesis and morphological changes in a sex-specific way, influencing neuronal injury/survival differently in both sexes.
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Affiliation(s)
| | | | - Mir Ahamed Hossain
- Department of Neurology, The Hugo W, Moser Research Institute at Kennedy Krieger, Baltimore, MD, USA.
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45
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Perrone S, Tataranno LM, Stazzoni G, Ramenghi L, Buonocore G. Brain susceptibility to oxidative stress in the perinatal period. J Matern Fetal Neonatal Med 2013; 28 Suppl 1:2291-5. [PMID: 23968388 DOI: 10.3109/14767058.2013.796170] [Citation(s) in RCA: 51] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Oxidative stress (OS) occurs at birth in all newborns as a consequence of the hyperoxic challenge due to the transition from the hypoxic intrauterine environment to extrauterine life. Free radical (FRs) sources such as inflammation, hyperoxia, hypoxia, ischaemia-reperfusion, neutrophil and macrophage activation, glutamate and free iron release, all increases the OS during the perinatal period. Newborns, and particularly preterm infants, have reduced antioxidant defences and are not able to counteract the harmful effects of FRs. Energy metabolism is central to life because cells cannot exist without an adequate supply of ATP. Due to its growth, the mammalian brain can be considered as a steady-state system in which ATP production matches ATP utilisation. The developing brain is particularly sensitive to any disturbances in energy generation, and even a short-term interruption can lead to long-lasting and irreversible damage. Whenever energy failure develops, brain damage can occur. Accumulating evidence indicates that OS is implicated in the pathogenesis of many neurological diseases, such as intraventricular haemorrhage, hypoxic-ischaemic encephalopathy and epilepsy.
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Affiliation(s)
- Serafina Perrone
- a Department of Pediatrics , Obstetrics and Reproduction Medicine, University of Siena , Siena , Italy and
| | - Luisa M Tataranno
- a Department of Pediatrics , Obstetrics and Reproduction Medicine, University of Siena , Siena , Italy and
| | - Gemma Stazzoni
- a Department of Pediatrics , Obstetrics and Reproduction Medicine, University of Siena , Siena , Italy and
| | - Luca Ramenghi
- b Neonatal Pathology Unit , Giannina Gaslini Hospital , Genova , Italy
| | - Giuseppe Buonocore
- a Department of Pediatrics , Obstetrics and Reproduction Medicine, University of Siena , Siena , Italy and
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46
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Sanderson TH, Reynolds CA, Kumar R, Przyklenk K, Hüttemann M. Molecular mechanisms of ischemia-reperfusion injury in brain: pivotal role of the mitochondrial membrane potential in reactive oxygen species generation. Mol Neurobiol 2012; 47:9-23. [PMID: 23011809 DOI: 10.1007/s12035-012-8344-z] [Citation(s) in RCA: 465] [Impact Index Per Article: 38.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2012] [Accepted: 08/27/2012] [Indexed: 12/20/2022]
Abstract
Stroke and circulatory arrest cause interferences in blood flow to the brain that result in considerable tissue damage. The primary method to reduce or prevent neurologic damage to patients suffering from brain ischemia is prompt restoration of blood flow to the ischemic tissue. However, paradoxically, restoration of blood flow causes additional damage and exacerbates neurocognitive deficits among patients who suffer a brain ischemic event. Mitochondria play a critical role in reperfusion injury by producing excessive reactive oxygen species (ROS) thereby damaging cellular components, and initiating cell death. In this review, we summarize our current understanding of the mechanisms of mitochondrial ROS generation during reperfusion, and specifically, the role the mitochondrial membrane potential plays in the pathology of cerebral ischemia/reperfusion. Additionally, we propose a temporal model of ROS generation in which posttranslational modifications of key oxidative phosphorylation (OxPhos) proteins caused by ischemia induce a hyperactive state upon reintroduction of oxygen. Hyperactive OxPhos generates high mitochondrial membrane potentials, a condition known to generate excessive ROS. Such a state would lead to a "burst" of ROS upon reperfusion, thereby causing structural and functional damage to the mitochondria and inducing cell death signaling that eventually culminate in tissue damage. Finally, we propose that strategies aimed at modulating this maladaptive hyperpolarization of the mitochondrial membrane potential may be a novel therapeutic intervention and present specific studies demonstrating the cytoprotective effect of this treatment modality.
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Affiliation(s)
- Thomas H Sanderson
- Cardiovascular Research Institute, Wayne State University School of Medicine, Detroit, MI 48201, USA.
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Sun Y, Zhang Y, Wang X, Blomgren K, Zhu C. Apoptosis-inducing factor downregulation increased neuronal progenitor, but not stem cell, survival in the neonatal hippocampus after cerebral hypoxia-ischemia. Mol Neurodegener 2012; 7:17. [PMID: 22534064 PMCID: PMC3464153 DOI: 10.1186/1750-1326-7-17] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2012] [Accepted: 04/25/2012] [Indexed: 11/23/2022] Open
Abstract
BACKGROUND A considerable proportion of all newly generated cells in the hippocampus will die before becoming fully differentiated, both under normal and pathological circumstances. The caspase-independent apoptosis-inducing factor (AIF) has not been investigated previously in this context. RESULTS Postnatal day 8 (P8) harlequin (Hq) mutant mice, expressing lower levels of AIF, and wild type littermates were injected with BrdU once daily for two days to label newborn cells. On P10 mice were subjected to hypoxia-ischemia (HI) and their brains were analyzed 4 h, 24 h or 4 weeks later. Overall tissue loss was 63.5% lower in Hq mice 4 weeks after HI. Short-term survival (4 h and 24 h) of labeled cells in the subgranular zone was neither affected by AIF downregulation, nor by HI. Long-term (4 weeks) survival of undifferentiated, BLBP-positive stem cells was reduced by half after HI, but this was not changed by AIF downregulation. Neurogenesis, however, as judged by BrdU/NeuN double labeling, was reduced by half after HI in wild type mice but preserved in Hq mice, indicating that primarily neural progenitors and neurons were protected. A wave of cell death started early after HI in the innermost layers of the granule cell layer (GCL) and moved outward, such that 24 h after HI dying cells could be detected in the entire GCL. CONCLUSIONS These findings demonstrate that AIF downregulation provides not only long-term overall neuroprotection after HI, but also protects neural progenitor cells, thereby rescuing hippocampal neurogenesis.
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Affiliation(s)
- Yanyan Sun
- Center for Brain Repair and Rehabilitation, Institute of Neuroscience and Physiology, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
- Department of Pediatrics, The Third Affiliated Hospital of Zhengzhou University, Zhengzhou, China
- Department of Pediatrics, Zhengzhou Children’s Hospital, Zhengzhou, China
| | - Yu Zhang
- Center for Brain Repair and Rehabilitation, Institute of Neuroscience and Physiology, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
- Department of Pediatrics, The Third Affiliated Hospital of Zhengzhou University, Zhengzhou, China
| | - Xiaoyang Wang
- Department of Pediatrics, The Third Affiliated Hospital of Zhengzhou University, Zhengzhou, China
- Perinatal Center, Institute of Neuroscience and Physiology, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
| | - Klas Blomgren
- Center for Brain Repair and Rehabilitation, Institute of Neuroscience and Physiology, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
- Department of Pediatrics, The Queen Silvia Children’s Hospital, University of Gothenburg, Gothenburg, Sweden
- Department of Women’s and Children’s Health, Karolinska Institutet, Karolinska University Hospital, Stockholm, Sweden
| | - Changlian Zhu
- Center for Brain Repair and Rehabilitation, Institute of Neuroscience and Physiology, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
- Department of Pediatrics, The Third Affiliated Hospital of Zhengzhou University, Zhengzhou, China
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48
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Park JM, Shin YJ, Kim HL, Cho JM, Lee MY. Sustained expression of osteopontin is closely associated with calcium deposits in the rat hippocampus after transient forebrain ischemia. J Histochem Cytochem 2012; 60:550-9. [PMID: 22496158 DOI: 10.1369/0022155412441707] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The present study was designed to evaluate the extent and topography of osteopontin (OPN) protein expression in the rat hippocampus 4 to 12 weeks following transient forebrain ischemia, and to compare OPN expression patterns with those of calcium deposits and astroglial and microglial reactions. Two patterns of OPN staining were recognized by light microscopy: 1) a diffuse pattern of tiny granular deposits throughout the CA1 region at 4 weeks after ischemia and 2) non-diffuse ovoid to round deposits, which formed conglomerates in the CA1 pyramidal cell layer over the chronic interval of 8 to 12 weeks. Immunogold-silver electron microscopy and electron probe microanalysis demonstrated that OPN deposits were indeed diverse types of calcium deposits, which were clearly delineated by profuse silver grains indicative of OPN expression. Intracellular OPN deposits were frequently observed within reactive astrocytes and neurons 4 weeks after ischemia but rarely at later times. By contrast, extracellular OPN deposits progressively increased in size and appeared to be gradually phagocytized by microglia or brain macrophages and some astrocytes over 8 to 12 weeks. These data indicate an interaction between OPN and calcium in the hippocampus in the chronic period after ischemia, suggesting that OPN binding to calcium deposits may be involved in scavenging mechanisms.
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Affiliation(s)
- Jang-Mi Park
- Department of Anatomy, College of Medicine, The Catholic University of Korea, Seoul, Korea
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Hypoxic-ischemic injury in the developing brain: the role of reactive oxygen species originating in mitochondria. Neurol Res Int 2012; 2012:542976. [PMID: 22548167 PMCID: PMC3323863 DOI: 10.1155/2012/542976] [Citation(s) in RCA: 78] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2011] [Revised: 11/12/2011] [Accepted: 11/22/2011] [Indexed: 02/01/2023] Open
Abstract
Mitochondrial dysfunction is the most fundamental mechanism of cell damage in cerebral hypoxia-ischemia and reperfusion. Mitochondrial respiratory chain (MRC) is increasingly recognized as a source for reactive oxygen species (ROS) in the postischemic tissue. Potentially, ROS originating in MRC can contribute to the reperfusion-driven oxidative stress, promoting mitochondrial membrane permeabilization. The loss of mitochondrial membranes integrity during reperfusion is considered as the major mechanism of secondary energy failure. This paper focuses on current data that support a pathogenic role of ROS originating from mitochondrial respiratory chain in the promotion of secondary energy failure and proposes potential therapeutic strategy against reperfusion-driven oxidative stress following hypoxia-ischemia-reperfusion injury of the developing brain.
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Rousset CI, Baburamani AA, Thornton C, Hagberg H. Mitochondria and perinatal brain injury. J Matern Fetal Neonatal Med 2012; 25 Suppl 1:35-8. [PMID: 22348594 DOI: 10.3109/14767058.2012.666398] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Secondary brain injury after hypoxia-ischemia is associated with delayed loss of high energy phosphates implicating bioenergetic mitochondrial failure at least partly related to deregulation of the energy sensor adenosine monophosphate-activated protein kinase. Furthermore, the toxic intracellular environment (accumulation of reactive oxygen/nitrosative species and intracellular calcium) during post-ischemic reperfusion triggers Bax-dependent mitochondrial permeabilization (MP) leading to activation of caspase-dependent and apoptosis-inducing factor dependent cell death. We still do not understand how MP is induced but some data suggest that mitochondrial fusion/fission as well as migration play a critical role. Mitochondrial dynamics also seem critical for brain development as genetic deficiency of proteins involved in mitochondrial fusion and fission results in malformations including microcephaly, abnormal brain development and dysmyelination. In this brief review, we update the critical role of mitochondria in brain development and the decision of cell fate after hypoxia-ischemia in the immature CNS.
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Affiliation(s)
- Catherine I Rousset
- Centre for the Developing Brain, Institute of Reproductive and Developmental biology, Department of Surgery & Cancer, Imperial College, Hammersmith Campus, London, UK
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