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Holubiec MI, Romero JI, Urbainsky C, Gellert M, Galeano P, Capani F, Lillig CH, Hanschmann EM. Nucleoredoxin Plays a Key Role in the Maintenance of Retinal Pigmented Epithelium Differentiation. Antioxidants (Basel) 2022; 11:antiox11061106. [PMID: 35740003 PMCID: PMC9220054 DOI: 10.3390/antiox11061106] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2022] [Revised: 05/29/2022] [Accepted: 05/29/2022] [Indexed: 02/05/2023] Open
Abstract
Nucleoredoxin (Nrx) belongs to the Thioredoxin protein family and functions in redox-mediated signal transduction. It contains the dithiol active site motif Cys-Pro-Pro-Cys and interacts and regulates different proteins in distinct cellular pathways. Nrx was shown to be catalytically active in the insulin assay and recent findings indicate that Nrx functions, in fact, as oxidase. Here, we have analyzed Nrx in the mammalian retina exposed to (perinatal) hypoxia-ischemia/reoxygenation, combining ex vivo and in vitro models. Our data show that Nrx regulates cell differentiation, which is important to (i) increase the number of glial cells and (ii) replenish neurons that are lost following the hypoxic insult. Nrx is essential to maintain cell morphology. These regulatory changes are related to VEGF but do not seem to be linked to the Wnt/β-catenin pathway, which is not affected by Nrx knock-down. In conclusion, our results strongly suggest that hypoxia-ischemia could lead to alterations in the organization of the retina, related to changes in RPE cell differentiation. Nrx may play an essential role in the maintenance of the RPE cell differentiation state via the regulation of VEGF release.
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Affiliation(s)
- Mariana I. Holubiec
- Facultad de Medicina, Instituto de Investigaciones Cardiológicas “Prof. Dr. Alberto C. Taquini” (ININCA), Universidad de Buenos Aires (UBA-CONICET), Buenos Aires 1122, Argentina;
- Instituto de Investigación en Biomedicina de Buenos Aires, Partner Institute of the MaxPlank Society (IBioBA-CONICET-MPSP), Buenos Aires 2390, Argentina
- Correspondence: (M.I.H.); (E.-M.H.); Tel.: +54-11-51618547 (M.I.H.); +49-211-8106040 (E.-M.H.)
| | - Juan I. Romero
- Instituto de Investigaciones Bioquímicas de Buenos Aires (IIBBA-CONICET), Fundación Instituto Leloir, Buenos Aires 1405, Argentina; (J.I.R.); (P.G.)
| | - Claudia Urbainsky
- Institute for Medical Biochemistry and Molecular Biology, University Medicine Greifswald, University of Greifswald, 17489 Greifswald, Germany; (C.U.); (M.G.); (C.H.L.)
| | - Manuela Gellert
- Institute for Medical Biochemistry and Molecular Biology, University Medicine Greifswald, University of Greifswald, 17489 Greifswald, Germany; (C.U.); (M.G.); (C.H.L.)
| | - Pablo Galeano
- Instituto de Investigaciones Bioquímicas de Buenos Aires (IIBBA-CONICET), Fundación Instituto Leloir, Buenos Aires 1405, Argentina; (J.I.R.); (P.G.)
| | - Francisco Capani
- Facultad de Medicina, Instituto de Investigaciones Cardiológicas “Prof. Dr. Alberto C. Taquini” (ININCA), Universidad de Buenos Aires (UBA-CONICET), Buenos Aires 1122, Argentina;
- Facultad de Medicina, Universidad Católica Argentina (UCA), Buenos Aires 1600, Argentina
| | - Christopher Horst Lillig
- Institute for Medical Biochemistry and Molecular Biology, University Medicine Greifswald, University of Greifswald, 17489 Greifswald, Germany; (C.U.); (M.G.); (C.H.L.)
| | - Eva-Maria Hanschmann
- Institute for Medical Biochemistry and Molecular Biology, University Medicine Greifswald, University of Greifswald, 17489 Greifswald, Germany; (C.U.); (M.G.); (C.H.L.)
- Department of Neurology, Medical Faculty, Heinrich-Heine University, 40225 Düsseldorf, Germany
- Correspondence: (M.I.H.); (E.-M.H.); Tel.: +54-11-51618547 (M.I.H.); +49-211-8106040 (E.-M.H.)
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Kieran NW, Suresh R, Dorion MF, MacDonald A, Blain M, Wen D, Fuh SC, Ryan F, Diaz RJ, Stratton JA, Ludwin SK, Sonnen JA, Antel J, Healy LM. MicroRNA-210 regulates the metabolic and inflammatory status of primary human astrocytes. J Neuroinflammation 2022; 19:10. [PMID: 34991629 PMCID: PMC8740343 DOI: 10.1186/s12974-021-02373-y] [Citation(s) in RCA: 23] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2021] [Accepted: 12/27/2021] [Indexed: 11/10/2022] Open
Abstract
Background Astrocytes are the most numerous glial cell type with important roles in maintaining homeostasis and responding to diseases in the brain. Astrocyte function is subject to modulation by microRNAs (miRs), which are short nucleotide strands that regulate protein expression in a post-transcriptional manner. Understanding the miR expression profile of astrocytes in disease settings provides insight into the cellular stresses present in the microenvironment and may uncover pathways of therapeutic interest.
Methods Laser-capture microdissection was used to isolate human astrocytes surrounding stroke lesions and those from neurological control tissue. Astrocytic miR expression profiles were examined using quantitative reverse transcription polymerase chain reaction (RT-qPCR). Primary human fetal astrocytes were cultured under in vitro stress conditions and transfection of a miR mimic was used to better understand how altered levels of miR-210 affect astrocyte function. The astrocytic response to stress was studied using qPCR, enzyme-linked immunosorbent assays (ELISAs), measurement of released lactate, and Seahorse. Results Here, we measured miR expression levels in astrocytes around human ischemic stroke lesions and observed differential expression of miR-210 in chronic stroke astrocytes compared to astrocytes from neurological control tissue. We also identified increased expression of miR-210 in mouse white matter tissue around middle cerebral artery occlusion (MCAO) brain lesions. We aimed to understand the role of miR-210 in primary human fetal astrocytes by developing an in vitro assay of hypoxic, metabolic, and inflammatory stresses. A combination of hypoxic and inflammatory stresses was observed to upregulate miR-210 expression. Transfection with miR-210-mimic (210M) increased glycolysis, enhanced lactate export, and promoted an anti-inflammatory transcriptional and translational signature in astrocytes. Additionally, 210M transfection resulted in decreased expression of complement 3 (C3) and semaphorin 5b (Sema5b). Conclusions We conclude that miR-210 expression in human astrocytes is modulated in response to ischemic stroke disease and under in vitro stress conditions, supporting a role for miR-210 in the astrocytic response to disease conditions. Further, the anti-inflammatory and pro-glycolytic impact of miR-210 on astrocytes makes it a potential candidate for further research as a neuroprotective agent. Supplementary Information The online version contains supplementary material available at 10.1186/s12974-021-02373-y.
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Affiliation(s)
- Nicholas W Kieran
- Neuroimmunology Unit, Montreal Neurological Institute, McGill University, Montreal, QC, Canada
| | - Rahul Suresh
- Department of Neurology and Neurosurgery, Montreal Neurological Institute, McGill University, Montreal, QC, Canada
| | - Marie-France Dorion
- Neuroimmunology Unit, Montreal Neurological Institute, McGill University, Montreal, QC, Canada
| | - Adam MacDonald
- Neuroimmunology Unit, Montreal Neurological Institute, McGill University, Montreal, QC, Canada
| | - Manon Blain
- Neuroimmunology Unit, Montreal Neurological Institute, McGill University, Montreal, QC, Canada
| | - Dingke Wen
- Neuroimmunology Unit, Montreal Neurological Institute, McGill University, Montreal, QC, Canada
| | - Shih-Chieh Fuh
- Neuroimmunology Unit, Montreal Neurological Institute, McGill University, Montreal, QC, Canada
| | - Fari Ryan
- Centre for Research in Neuroscience, The Research Institute of the McGill University Health Center, Montreal, QC, Canada
| | - Roberto J Diaz
- Department of Neurology and Neurosurgery, Montreal Neurological Institute, McGill University, Montreal, QC, Canada
| | - Jo Anne Stratton
- Neuroimmunology Unit, Montreal Neurological Institute, McGill University, Montreal, QC, Canada
| | - Samuel K Ludwin
- Department of Pathology, Queen's University, Kingston, ON, Canada
| | - Joshua A Sonnen
- Departments of Pathology, Neurology and Neurosurgery, McGill University, Montreal, QC, Canada
| | - Jack Antel
- Neuroimmunology Unit, Montreal Neurological Institute, McGill University, Montreal, QC, Canada
| | - Luke M Healy
- Neuroimmunology Unit, Montreal Neurological Institute, McGill University, Montreal, QC, Canada.
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Increased Calbindin D28k Expression via Long-Term Alternate-Day Fasting Does Not Protect against Ischemia-Reperfusion Injury: A Focus on Delayed Neuronal Death, Gliosis and Immunoglobulin G Leakage. Int J Mol Sci 2021; 22:ijms22020644. [PMID: 33440708 PMCID: PMC7827208 DOI: 10.3390/ijms22020644] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2020] [Revised: 01/06/2021] [Accepted: 01/06/2021] [Indexed: 01/02/2023] Open
Abstract
Calbindin-D28k (CB), a calcium-binding protein, mediates diverse neuronal functions. In this study, adult gerbils were fed a normal diet (ND) or exposed to intermittent fasting (IF) for three months, and were randomly assigned to sham or ischemia operated groups. Ischemic injury was induced by transient forebrain ischemia for 5 min. Short-term memory was examined via passive avoidance test. CB expression was investigated in the Cornu Ammonis 1 (CA1) region of the hippocampus via western blot analysis and immunohistochemistry. Finally, histological analysis was used to assess neuroprotection and gliosis (microgliosis and astrogliosis) in the CA1 region. Short-term memory did not vary significantly between ischemic gerbils with IF and those exposed to ND. CB expression was increased significantly in the CA1 pyramidal neurons of ischemic gerbils with IF compared with that of gerbils fed ND. However, the CB expression was significantly decreased in ischemic gerbils with IF, similarly to that of ischemic gerbils exposed to ND. The CA1 pyramidal neurons were not protected from ischemic injury in both groups, and gliosis (astrogliosis and microgliosis) was gradually increased with time after ischemia. In addition, immunoglobulin G was leaked into the CA1 parenchyma from blood vessels and gradually increased with time after ischemic insult in both groups. Taken together, our study suggests that IF for three months increases CB expression in hippocampal CA1 pyramidal neurons; however, the CA1 pyramidal neurons are not protected from transient forebrain ischemia. This failure in neuroprotection may be attributed to disruption of the blood–brain barrier, which triggers gliosis after ischemic insults.
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Hao Y, Xin M, Feng L, Wang X, Wang X, Ma D, Feng J. Review Cerebral Ischemic Tolerance and Preconditioning: Methods, Mechanisms, Clinical Applications, and Challenges. Front Neurol 2020; 11:812. [PMID: 33071923 PMCID: PMC7530891 DOI: 10.3389/fneur.2020.00812] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2020] [Accepted: 06/29/2020] [Indexed: 12/13/2022] Open
Abstract
Stroke is one of the leading causes of morbidity and mortality worldwide, and it is increasing in prevalence. The limited therapeutic window and potential severe side effects prevent the widespread clinical application of the venous injection of thrombolytic tissue plasminogen activator and thrombectomy, which are regarded as the only approved treatments for acute ischemic stroke. Triggered by various types of mild stressors or stimuli, ischemic preconditioning (IPreC) induces adaptive endogenous tolerance to ischemia/reperfusion (I/R) injury by activating a multitude cascade of biomolecules, for example, proteins, enzymes, receptors, transcription factors, and others, which eventually lead to transcriptional regulation and epigenetic and genomic reprogramming. During the past 30 years, IPreC has been widely studied to confirm its neuroprotection against subsequent I/R injury, mainly including local ischemic preconditioning (LIPreC), remote ischemic preconditioning (RIPreC), and cross preconditioning. Although LIPreC has a strong neuroprotective effect, the clinical application of IPreC for subsequent cerebral ischemia is difficult. There are two main reasons for the above result: Cerebral ischemia is unpredictable, and LIPreC is also capable of inducing unexpected injury with only minor differences to durations or intensity. RIPreC and pharmacological preconditioning, an easy-to-use and non-invasive therapy, can be performed in a variety of clinical settings and appear to be more suitable for the clinical management of ischemic stroke. Hoping to advance our understanding of IPreC, this review mainly focuses on recent advances in IPreC in stroke management, its challenges, and the potential study directions.
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Affiliation(s)
| | | | | | | | | | - Di Ma
- Department of Neurology and Neuroscience Center, The First Hospital of Jilin University, Changchun, China
| | - Jiachun Feng
- Department of Neurology and Neuroscience Center, The First Hospital of Jilin University, Changchun, China
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Ohk TG, Ahn JH, Park YE, Lee TK, Kim B, Lee JC, Cho JH, Park JH, Won MH, Lee CH. Comparison of neuronal death and expression of TNF‑α and MCT4 in the gerbil hippocampal CA1 region induced by ischemia/reperfusion under hyperthermia to those under normothermia. Mol Med Rep 2020; 22:1044-1052. [PMID: 32468005 PMCID: PMC7339721 DOI: 10.3892/mmr.2020.11182] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2020] [Accepted: 05/12/2020] [Indexed: 12/19/2022] Open
Abstract
Monocarboxylate transporter 4 (MCT4) is a high-capacity lactate transporter in cells and the alteration in MCT4 expression harms cellular survival. The present study investigated whether hypothermia affects tumor necrosis factor-α (TNF-α) and MCT4 immunoreactivity in the subfield cornu ammonis 1 (CA1) following cerebral ischemia/reperfusion (IR) in gerbils. Hypothermia was induced for 30 min before and during ischemia. It was found that IR-induced death of pyramidal neurons was markedly augmented and occurred faster under hyperthermia than under normothermia. TNF-α immunoreactivity in the pyramidal cells started to increase at 3 h after IR and peaked at 1 day after IR under normothermia. However, in hyperthermic control and sham operated gerbils, TNF-α immunoreactivity was significantly increased compared with the normothermic gerbils, and IR under hyperthermia caused a more rapid and significant increase in TNF-α immunoreactivity in pyramidal neurons than under normothermia. In addition, in the normothermic gerbils, MCT4 immunoreactivity began to decrease in pyramidal neurons from 3 h after IR and markedly increased at 1 and 2 days after IR. On the other hand, MCT4 immunoreactivity in pyramidal neurons of the hyperthermic gerbils was significantly increased from 3 h after IR, maintained until 1 day after IR and markedly decreased at 2 days after IR. These results indicate that acceleration of IR-induced neuronal death under hyperthermia might be closely associated with early alteration of TNF-α and MCT4 protein expression in the gerbil hippocampus after IR.
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Affiliation(s)
- Taek Geun Ohk
- Department of Emergency Medicine, and Institute of Medical Sciences, Kangwon National University Hospital, School of Medicine, Kangwon National University, Chuncheon, Gangwon 24289, Republic of Korea
| | - Ji Hyeon Ahn
- Department of Biomedical Science, Research Institute of Bioscience and Biotechnology, Hallym University, Chuncheon, Gangwon 24252, Republic of Korea
| | - Young Eun Park
- Department of Neurobiology, School of Medicine, Kangwon National University, Chuncheon, Gangwon 24341, Republic of Korea
| | - Tae-Kyeong Lee
- Department of Biomedical Science, Research Institute of Bioscience and Biotechnology, Hallym University, Chuncheon, Gangwon 24252, Republic of Korea
| | - Bora Kim
- Department of Neurobiology, School of Medicine, Kangwon National University, Chuncheon, Gangwon 24341, Republic of Korea
| | - Jae-Chul Lee
- Department of Neurobiology, School of Medicine, Kangwon National University, Chuncheon, Gangwon 24341, Republic of Korea
| | - Jun Hwi Cho
- Department of Emergency Medicine, and Institute of Medical Sciences, Kangwon National University Hospital, School of Medicine, Kangwon National University, Chuncheon, Gangwon 24289, Republic of Korea
| | - Joon Ha Park
- Department of Anatomy, College of Korean Medicine, Dongguk University, Gyeongju, Gyeongbuk 38066, Republic of Korea
| | - Moo-Ho Won
- Department of Neurobiology, School of Medicine, Kangwon National University, Chuncheon, Gangwon 24341, Republic of Korea
| | - Choong-Hyun Lee
- Department of Pharmacy, College of Pharmacy, Dankook University, Cheonan, Chungcheongnam 31116, Republic of Korea
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Camberos-Luna L, Massieu L. Therapeutic strategies for ketosis induction and their potential efficacy for the treatment of acute brain injury and neurodegenerative diseases. Neurochem Int 2019; 133:104614. [PMID: 31785349 DOI: 10.1016/j.neuint.2019.104614] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2019] [Revised: 11/26/2019] [Accepted: 11/26/2019] [Indexed: 12/13/2022]
Abstract
The therapeutic use of ketone bodies (KB) against acute brain injury and neurodegenerative disorders has lately been suggested by many studies. Several mechanisms responsible for the protective action of KB have been described, including metabolic, anti-inflammatory and epigenetic. However, it is still not clear whether a specific mechanism of action can be associated with a particular neurological disorder. Different strategies to induce ketosis including the ketogenic diet (KD), caloric restriction (CR), intermittent fasting (IF), as well as the administration of medium chain triglycerides (MCTs), exogenous ketones or KB derivatives, have been used in animal models of brain injury and in humans. They have shown different degrees of success to prevent neuronal damage, motor alterations and cognitive decline. However, more investigation is needed in order to establish safe protocols for clinical application. Throughout the present review, we describe the different approaches that have been used to elevate blood KB and discuss their effectiveness considering their advantages and limitations, as tested in models of brain injury, neurodegeneration and clinical research. We also describe the mechanisms of action of KB in non-pathologic conditions and in association with their protective effect against neuronal damage in acute neurological disorders and neurodegenerative diseases.
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Affiliation(s)
- Lucy Camberos-Luna
- División de Neurociencias, Instituto de Fisiología Celular, Universidad Nacional Autónoma de México, Ciudad de México, CP 04510, Mexico.
| | - Lourdes Massieu
- División de Neurociencias, Instituto de Fisiología Celular, Universidad Nacional Autónoma de México, Ciudad de México, CP 04510, Mexico.
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Alvarez-Flores MP, Hébert A, Gouelle C, Geller S, Chudzinski-Tavassi AM, Pellerin L. Neuroprotective effect of rLosac on supplement-deprived mouse cultured cortical neurons involves maintenance of monocarboxylate transporter MCT2 protein levels. J Neurochem 2018; 148:80-96. [PMID: 30347438 DOI: 10.1111/jnc.14617] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2018] [Revised: 09/02/2018] [Accepted: 10/17/2018] [Indexed: 01/08/2023]
Abstract
The recombinant Lonomia obliqua Stuart-factor activator (rLosac) is a recombinant hemolin which belongs to the immunoglobulin superfamily of cell adhesion molecules. It is capable of inducing pro-survival activity in serum-deprived human umbilical vein endothelial cells (HUVECs) and fibroblasts by increasing mitochondrial metabolism. We hypothesize that it could promote neuronal survival by acting on neuroenergetics. Our study reveals that treatment of primary mouse cortical neurons cultured in neurobasal medium lacking B27 supplement with rLosac led to an enhancement of cell viability in a time- and concentration-dependent manner. In parallel, preserved or enhanced phosphorylation of Akt, p44, and p42 MAPK, as well as mTOR was observed following treatment with rLosac. During deprivation, as assessed by western blot and qRT-PCR, protein and mRNA expression of MCT2 (the predominant neuronal monocarboxylate transporter allowing lactate use as an alternative energy substrate) decreased significantly in B27 supplement-deprived cortical neurons and was hardly detected after 24 h of deprivation. Interestingly, rLosac maintained MCT2 protein expression after 24 h of deprivation including at the cell surface without preventing mRNA loss. MCT2 knockdown reduced rLosac-enhanced cell viability, confirming its involvement in rLosac effect. Enhanced uptake of lactate was detected following rLosac treatment and might contribute to rLosac-enhanced viability during deprivation. In the presence of both lactate and rLosac, cell viability was higher than in the presence of lactate alone. Our observations suggest that rLosac promotes cell viability in stressed (B27 supplement-deprived) neurons by facilitating the use of lactate as energy substrate via the preservation of MCT2 protein expression. OPEN SCIENCE BADGES: This article has received a badge for *Open Materials* because it provided all relevant information to reproduce the study in the manuscript. The complete Open Science Disclosure form for this article can be found at the end of the article. More information about the Open Practices badges can be found at https://cos.io/our-services/open-science-badges/.
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Affiliation(s)
- Miryam P Alvarez-Flores
- Department of Physiology, University of Lausanne, Lausanne, Switzerland.,Laboratory of Molecular Biology - Centre of Excellence in New Target Discover CENTD, Butantan Institute, São Paulo, Brazil
| | - Audrey Hébert
- Department of Physiology, University of Lausanne, Lausanne, Switzerland
| | - Cathy Gouelle
- Department of Physiology, University of Lausanne, Lausanne, Switzerland
| | - Sarah Geller
- Department of Physiology, University of Lausanne, Lausanne, Switzerland
| | - Ana M Chudzinski-Tavassi
- Laboratory of Molecular Biology - Centre of Excellence in New Target Discover CENTD, Butantan Institute, São Paulo, Brazil
| | - Luc Pellerin
- Department of Physiology, University of Lausanne, Lausanne, Switzerland.,Centre de Résonance Magnétique des Systèmes Biologiques, UMR5536 CNRS, LabEx TRAIL-IBIO, Université de Bordeaux, Bordeaux Cedex, France
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8
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Yoo DY, Park JH, Lee KY, Kwon HJ, Jung HY, Kim JW, Kim DW, Choi JH, Moon SM, Yoon YS, Won MH, Hwang IK. Temporal and spatial changes of monocarboxylate transporter 4 expression in the hippocampal CA1 region following transient forebrain ischemia in the Mongolian gerbil. Mol Med Rep 2017; 15:4225-4230. [PMID: 28440446 DOI: 10.3892/mmr.2017.6508] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2016] [Accepted: 02/13/2017] [Indexed: 11/06/2022] Open
Abstract
Transient forebrain ischemia depletes glucose and oxygen levels in the brain. In this pathological condition, lactate serves an important role in cellular metabolism as the end product of glycolysis. The present study investigated the expression of monocarboxylate transporter 4 (MCT4) in lactate metabolism in the hippocampal CA1 region following induction of transient forebrain ischemia. MCT4 immunoreactivity was detected in CA1 pyramidal cells of the sham-operated group. Animals from the ischemic group exhibited a transient decrease in MCT4 immunoreactivity in the CA1 region between 30 min and 3 h following ischemia compared with the sham‑operated group. The initial decrease in immunoreactivity observed between 30 min and 3 h following ischemia was followed by an increase at 2 days after the treatment. A significant increase in MCT4 immunoreactivity levels was observed 2 days after ischemia compared with the sham‑operated group. Limited MCT4 immunoreactivity was observed in the pyramidal neurons 3 days after ischemia. At 4‑10 days after ischemia, MCT4 immunoreactivity was detected in the strata radiatum, oriens and pyramidale. Furthermore, MCT4 immunoreactivity levels in the CA1 region exhibited a time‑dependent increase following ischemia. The results indicated that there were transient alterations observed in the localization of MCT4 following the induction of ischemia, and further studies are required to investigate the association between MCT4 expression and lactate metabolism in providing energy to the post‑ischemic brain.
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Affiliation(s)
- Dae Young Yoo
- Department of Anatomy and Cell Biology, College of Veterinary Medicine and Research Institute for Veterinary Science, Seoul National University, Seoul 08826, Republic of Korea
| | - Joon Ha Park
- Department of Neurobiology, School of Medicine, Kangwon National University, Chuncheon, Gangwon 24341, Republic of Korea
| | - Kwon Young Lee
- Department of Anatomy, College of Veterinary Medicine, Kangwon National University, Chuncheon, Gangwon 24341, Republic of Korea
| | - Hyun Jung Kwon
- Department of Biochemistry and Molecular Biology, Research Institute of Oral Sciences, College of Dentistry, Gangneung‑Wonju National University, Gangneung, Gangwon 25457, Republic of Korea
| | - Hyo Young Jung
- Department of Anatomy and Cell Biology, College of Veterinary Medicine and Research Institute for Veterinary Science, Seoul National University, Seoul 08826, Republic of Korea
| | - Jong Whi Kim
- Department of Anatomy and Cell Biology, College of Veterinary Medicine and Research Institute for Veterinary Science, Seoul National University, Seoul 08826, Republic of Korea
| | - Dae Won Kim
- Department of Biochemistry and Molecular Biology, Research Institute of Oral Sciences, College of Dentistry, Gangneung‑Wonju National University, Gangneung, Gangwon 25457, Republic of Korea
| | - Jung Hoon Choi
- Department of Anatomy, College of Veterinary Medicine, Kangwon National University, Chuncheon, Gangwon 24341, Republic of Korea
| | - Seung Myung Moon
- Department of Neurosurgery, Dongtan Sacred Heart Hospital, College of Medicine, Hallym University, Hwaseong, Gyeonggi 18450, Republic of Korea
| | - Yeo Sung Yoon
- Department of Anatomy and Cell Biology, College of Veterinary Medicine and Research Institute for Veterinary Science, Seoul National University, Seoul 08826, Republic of Korea
| | - Moo-Ho Won
- Department of Neurobiology, School of Medicine, Kangwon National University, Chuncheon, Gangwon 24341, Republic of Korea
| | - In Koo Hwang
- Department of Anatomy and Cell Biology, College of Veterinary Medicine and Research Institute for Veterinary Science, Seoul National University, Seoul 08826, Republic of Korea
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9
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Yao H, Azad P, Zhao HW, Wang J, Poulsen O, Freitas BC, Muotri AR, Haddad GG. The Na +/HCO 3- co-transporter is protective during ischemia in astrocytes. Neuroscience 2016; 339:329-337. [PMID: 27717805 DOI: 10.1016/j.neuroscience.2016.09.050] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2016] [Revised: 09/24/2016] [Accepted: 09/29/2016] [Indexed: 02/03/2023]
Abstract
The sodium bicarbonate co-transporter (NBC) is the major bicarbonate-dependent acid-base transporter in mammalian astrocytes and has been implicated in ischemic brain injury. A malfunction of astrocytes could have great impact on the outcome of stroke due to their participation in the formation of blood-brain barrier, synaptic transmission, and electrolyte balance in the human brain. Nevertheless, the role of NBC in the ischemic astrocyte death has not been well understood. In this work, we obtained skin biopsies from healthy human subjects and had their fibroblasts grown in culture and reprogrammed into human-induced pluripotent stem cells (hiPSCs). These hiPSCs were further differentiated into neuroprogenitor cells (NPCs) and then into human astrocytes. These astrocytes express GFAP and S100β and readily propagate calcium waves upon mechanical stimulation. Using pH-sensitive dye BCECF [2',7'-bis-(carboxyethyl)-5-(and-6)-carboxyfluorescein] and qPCR technique, we have confirmed that these astrocytes express functional NBC including electrogenic NBC (NBCe). In addition, astrocytes exposed to an ischemic solution (IS) that mimics the ischemic penumbral environment enhanced both mRNA and protein expression level of NBCe1 in astrocytes. Using IS and a generic NBC blocker S0859, we have studied the involvement of NBC in IS-induced human astrocytes death. Our results show that a 30μM S0859 induced a 97.5±1.6% (n=10) cell death in IS-treated astrocytes, which is significantly higher than 43.6±4.5%, (n=10) in the control group treated with IS alone. In summary, a NBC blocker exaggerates IS-induced cell death, suggesting that NBC activity is essential for astrocyte survival when exposed to ischemic penumbral environment.
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Affiliation(s)
- Hang Yao
- Departments of Pediatrics, University of California San Diego, La Jolla, CA 92093, United States
| | - Priti Azad
- Departments of Pediatrics, University of California San Diego, La Jolla, CA 92093, United States
| | - Huiwen W Zhao
- Departments of Pediatrics, University of California San Diego, La Jolla, CA 92093, United States
| | - Juan Wang
- Departments of Pediatrics, University of California San Diego, La Jolla, CA 92093, United States
| | - Orit Poulsen
- Departments of Pediatrics, University of California San Diego, La Jolla, CA 92093, United States
| | - Beatriz C Freitas
- Department of Pediatrics/Rady Children's Hospital San Diego, Department of Cellular & Molecular Medicine, Stem Cell Program, La Jolla, CA 92093, United States
| | - Alysson R Muotri
- Department of Pediatrics/Rady Children's Hospital San Diego, Department of Cellular & Molecular Medicine, Stem Cell Program, La Jolla, CA 92093, United States
| | - Gabriel G Haddad
- Departments of Pediatrics & Neuroscience, University of California-San Diego, La Jolla, CA 92093, United States; Rady Children's Hospital-San Diego, San Diego, CA 92123, United States.
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10
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Jha MK, Lee IK, Suk K. Metabolic reprogramming by the pyruvate dehydrogenase kinase-lactic acid axis: Linking metabolism and diverse neuropathophysiologies. Neurosci Biobehav Rev 2016; 68:1-19. [PMID: 27179453 DOI: 10.1016/j.neubiorev.2016.05.006] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2016] [Revised: 04/11/2016] [Accepted: 05/09/2016] [Indexed: 12/12/2022]
Abstract
Emerging evidence indicates that there is a complex interplay between metabolism and chronic disorders in the nervous system. In particular, the pyruvate dehydrogenase (PDH) kinase (PDK)-lactic acid axis is a critical link that connects metabolic reprogramming and the pathophysiology of neurological disorders. PDKs, via regulation of PDH complex activity, orchestrate the conversion of pyruvate either aerobically to acetyl-CoA, or anaerobically to lactate. The kinases are also involved in neurometabolic dysregulation under pathological conditions. Lactate, an energy substrate for neurons, is also a recently acknowledged signaling molecule involved in neuronal plasticity, neuron-glia interactions, neuroimmune communication, and nociception. More recently, the PDK-lactic acid axis has been recognized to modulate neuronal and glial phenotypes and activities, contributing to the pathophysiologies of diverse neurological disorders. This review covers the recent advances that implicate the PDK-lactic acid axis as a novel linker of metabolism and diverse neuropathophysiologies. We finally explore the possibilities of employing the PDK-lactic acid axis and its downstream mediators as putative future therapeutic strategies aimed at prevention or treatment of neurological disorders.
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Affiliation(s)
- Mithilesh Kumar Jha
- Department of Pharmacology, Brain Science and Engineering Institute, BK21 PLUS KNU Biomedical Convergence Program, Kyungpook National University School of Medicine, Daegu, Republic of Korea; Department of Neurology, Division of Neuromuscular Medicine, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - In-Kyu Lee
- Department of Internal Medicine, Division of Endocrinology and Metabolism, Kyungpook National University School of Medicine, Daegu, Republic of Korea
| | - Kyoungho Suk
- Department of Pharmacology, Brain Science and Engineering Institute, BK21 PLUS KNU Biomedical Convergence Program, Kyungpook National University School of Medicine, Daegu, Republic of Korea.
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