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Kennedy L, Glesaaen ER, Palibrk V, Pannone M, Wang W, Al-Jabri A, Suganthan R, Meyer N, Austbø ML, Lin X, Bergersen LH, Bjørås M, Rinholm JE. Lactate receptor HCAR1 regulates neurogenesis and microglia activation after neonatal hypoxia-ischemia. eLife 2022; 11:76451. [PMID: 35942676 PMCID: PMC9363115 DOI: 10.7554/elife.76451] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2021] [Accepted: 06/30/2022] [Indexed: 12/26/2022] Open
Abstract
Neonatal cerebral hypoxia-ischemia (HI) is the leading cause of death and disability in newborns with the only current treatment being hypothermia. An increased understanding of the pathways that facilitate tissue repair after HI may aid the development of better treatments. Here, we study the role of lactate receptor HCAR1 in tissue repair after neonatal HI in mice. We show that HCAR1 knockout mice have reduced tissue regeneration compared with wildtype mice. Furthermore, proliferation of neural progenitor cells and glial cells, as well as microglial activation was impaired. Transcriptome analysis showed a strong transcriptional response to HI in the subventricular zone of wildtype mice involving about 7300 genes. In contrast, the HCAR1 knockout mice showed a modest response, involving about 750 genes. Notably, fundamental processes in tissue repair such as cell cycle and innate immunity were dysregulated in HCAR1 knockout. Our data suggest that HCAR1 is a key transcriptional regulator of pathways that promote tissue regeneration after HI.
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Affiliation(s)
- Lauritz Kennedy
- Department of Microbiology, Oslo University Hospital and University of Oslo, Oslo, Norway.,Division of Physiology, Institute of Basic Medical Sciences, University of Oslo, Oslo, Norway
| | - Emilie R Glesaaen
- Department of Microbiology, Oslo University Hospital and University of Oslo, Oslo, Norway.,Division of Physiology, Institute of Basic Medical Sciences, University of Oslo, Oslo, Norway
| | - Vuk Palibrk
- Department of Clinical and Molecular Medicine, Norwegian University of Science and Technology, Trondheim, Norway
| | - Marco Pannone
- Department of Microbiology, Oslo University Hospital and University of Oslo, Oslo, Norway.,Department of Clinical and Molecular Medicine, Norwegian University of Science and Technology, Trondheim, Norway
| | - Wei Wang
- Department of Clinical and Molecular Medicine, Norwegian University of Science and Technology, Trondheim, Norway
| | - Ali Al-Jabri
- Department of Microbiology, Oslo University Hospital and University of Oslo, Oslo, Norway.,Division of Physiology, Institute of Basic Medical Sciences, University of Oslo, Oslo, Norway
| | - Rajikala Suganthan
- Department of Microbiology, Oslo University Hospital and University of Oslo, Oslo, Norway
| | - Niklas Meyer
- Department of Microbiology, Oslo University Hospital and University of Oslo, Oslo, Norway.,Division of Physiology, Institute of Basic Medical Sciences, University of Oslo, Oslo, Norway
| | - Marie Landa Austbø
- Department of Microbiology, Oslo University Hospital and University of Oslo, Oslo, Norway
| | - Xiaolin Lin
- Department of Microbiology, Oslo University Hospital and University of Oslo, Oslo, Norway.,Department of Clinical and Molecular Medicine, Norwegian University of Science and Technology, Trondheim, Norway
| | - Linda H Bergersen
- The Brain and Muscle Energy Group, Institute of Oral Biology, Faculty of Dentistry, University of Oslo, Oslo, Norway.,Center for Healthy Aging, Department of Neuroscience and Pharmacology, Faculty of Health Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Magnar Bjørås
- Department of Microbiology, Oslo University Hospital and University of Oslo, Oslo, Norway.,Department of Clinical and Molecular Medicine, Norwegian University of Science and Technology, Trondheim, Norway
| | - Johanne E Rinholm
- Department of Microbiology, Oslo University Hospital and University of Oslo, Oslo, Norway.,Division of Physiology, Institute of Basic Medical Sciences, University of Oslo, Oslo, Norway
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2
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Lauritzen KH, Olsen MB, Ahmed MS, Yang K, Rinholm JE, Bergersen LH, Esbensen QY, Sverkeli LJ, Ziegler M, Attramadal H, Halvorsen B, Aukrust P, Yndestad A. Instability in NAD + metabolism leads to impaired cardiac mitochondrial function and communication. eLife 2021; 10:59828. [PMID: 34343089 PMCID: PMC8331182 DOI: 10.7554/elife.59828] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2020] [Accepted: 07/06/2021] [Indexed: 12/18/2022] Open
Abstract
Poly(ADP-ribose) polymerase (PARP) enzymes initiate (mt)DNA repair mechanisms and use nicotinamide adenine dinucleotide (NAD+) as energy source. Prolonged PARP activity can drain cellular NAD+ reserves, leading to de-regulation of important molecular processes. Here, we provide evidence of a pathophysiological mechanism that connects mtDNA damage to cardiac dysfunction via reduced NAD+ levels and loss of mitochondrial function and communication. Using a transgenic model, we demonstrate that high levels of mice cardiomyocyte mtDNA damage cause a reduction in NAD+ levels due to extreme DNA repair activity, causing impaired activation of NAD+-dependent SIRT3. In addition, we show that myocardial mtDNA damage in combination with high dosages of nicotinamideriboside (NR) causes an inhibition of sirtuin activity due to accumulation of nicotinamide (NAM), in addition to irregular cardiac mitochondrial morphology. Consequently, high doses of NR should be used with caution, especially when cardiomyopathic symptoms are caused by mitochondrial dysfunction and instability of mtDNA.
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Affiliation(s)
- Knut H Lauritzen
- Research Institute of Internal Medicine, Oslo University Hospital, Rikshospitalet and University of Oslo, Oslo, Norway
| | - Maria Belland Olsen
- Research Institute of Internal Medicine, Oslo University Hospital, Rikshospitalet and University of Oslo, Oslo, Norway
| | - Mohammed Shakil Ahmed
- Institute for Surgical Research, Oslo University Hospital and University of Oslo, Oslo, Norway
| | - Kuan Yang
- Research Institute of Internal Medicine, Oslo University Hospital, Rikshospitalet and University of Oslo, Oslo, Norway
| | | | - Linda H Bergersen
- Department of Oral Biology, University of Oslo, Oslo, Norway.,Department of Neuroscience and Pharmacology, Center for Healthy Aging, University of Copenhagen, Copenhagen, Denmark
| | - Qin Ying Esbensen
- Department of Clinical Molecular Biology, University of Oslo and Akershus University Hospital, Nordbyhagen, Norway
| | | | - Mathias Ziegler
- Department of Biomedicine, University of Bergen, Bergen, Norway
| | - Håvard Attramadal
- Institute for Surgical Research, Oslo University Hospital and University of Oslo, Oslo, Norway
| | - Bente Halvorsen
- Research Institute of Internal Medicine, Oslo University Hospital, Rikshospitalet and University of Oslo, Oslo, Norway.,Institute of Clinical Medicine, University of Oslo, Faculty of Medicine, Oslo, Norway
| | - Pål Aukrust
- Research Institute of Internal Medicine, Oslo University Hospital, Rikshospitalet and University of Oslo, Oslo, Norway.,Institute of Clinical Medicine, University of Oslo, Faculty of Medicine, Oslo, Norway.,Section of Clinical Immunology and Infectious Diseases, Oslo University Hospital Rikshospitalet, Oslo, Norway
| | - Arne Yndestad
- Research Institute of Internal Medicine, Oslo University Hospital, Rikshospitalet and University of Oslo, Oslo, Norway.,Institute of Clinical Medicine, University of Oslo, Faculty of Medicine, Oslo, Norway
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3
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Hadzic A, Nguyen TD, Hosoyamada M, Tomioka NH, Bergersen LH, Storm-Mathisen J, Morland C. The Lactate Receptor HCA 1 Is Present in the Choroid Plexus, the Tela Choroidea, and the Neuroepithelial Lining of the Dorsal Part of the Third Ventricle. Int J Mol Sci 2020; 21:E6457. [PMID: 32899645 PMCID: PMC7554735 DOI: 10.3390/ijms21186457] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2020] [Revised: 08/31/2020] [Accepted: 09/02/2020] [Indexed: 01/01/2023] Open
Abstract
The volume, composition, and movement of the cerebrospinal fluid (CSF) are important for brain physiology, pathology, and diagnostics. Nevertheless, few studies have focused on the main structure that produces CSF, the choroid plexus (CP). Due to the presence of monocarboxylate transporters (MCTs) in the CP, changes in blood and brain lactate levels are reflected in the CSF. A lactate receptor, the hydroxycarboxylic acid receptor 1 (HCA1), is present in the brain, but whether it is located in the CP or in other periventricular structures has not been studied. Here, we investigated the distribution of HCA1 in the cerebral ventricular system using monomeric red fluorescent protein (mRFP)-HCA1 reporter mice. The reporter signal was only detected in the dorsal part of the third ventricle, where strong mRFP-HCA1 labeling was present in cells of the CP, the tela choroidea, and the neuroepithelial ventricular lining. Co-labeling experiments identified these cells as fibroblasts (in the CP, the tela choroidea, and the ventricle lining) and ependymal cells (in the tela choroidea and the ventricle lining). Our data suggest that the HCA1-containing fibroblasts and ependymal cells have the ability to respond to alterations in CSF lactate in body-brain signaling, but also as a sign of neuropathology (e.g., stroke and Alzheimer's disease biomarker).
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Affiliation(s)
- Alena Hadzic
- Section for Pharmacology and Pharmaceutical Biosciences, Department of Pharmacy, The Faculty of Mathematics and Natural Sciences, University of Oslo, NO-0316 Oslo, Norway; (A.H.); (T.D.N.)
| | - Teresa D. Nguyen
- Section for Pharmacology and Pharmaceutical Biosciences, Department of Pharmacy, The Faculty of Mathematics and Natural Sciences, University of Oslo, NO-0316 Oslo, Norway; (A.H.); (T.D.N.)
| | - Makoto Hosoyamada
- Department of Human Physiology and Pathology, Faculty of Pharma-Science, Teikyo University, Tokyo 173-8605, Japan; (M.H.); (N.H.T.)
| | - Naoko H. Tomioka
- Department of Human Physiology and Pathology, Faculty of Pharma-Science, Teikyo University, Tokyo 173-8605, Japan; (M.H.); (N.H.T.)
| | - Linda H. Bergersen
- The Brain and Muscle Energy Group, Institute of Oral Biology, Faculty of Dentistry, University of Oslo, NO-0318 Oslo, Norway;
- Center for Healthy Aging, Department of Neuroscience and Pharmacology, Faculty of Health Sciences, University of Copenhagen, DK-2200 Copenhagen N, Denmark
| | - Jon Storm-Mathisen
- Amino Acid Transporter Laboratory, Division of Anatomy, Department of Molecular Medicine, Institute of Basic Medical Sciences, Faculty of Medicine, Healthy Brain Aging Centre, University of Oslo, NO-0317 Oslo, Norway;
| | - Cecilie Morland
- Section for Pharmacology and Pharmaceutical Biosciences, Department of Pharmacy, The Faculty of Mathematics and Natural Sciences, University of Oslo, NO-0316 Oslo, Norway; (A.H.); (T.D.N.)
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4
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Cunnane SC, Trushina E, Morland C, Prigione A, Casadesus G, Andrews ZB, Beal MF, Bergersen LH, Brinton RD, de la Monte S, Eckert A, Harvey J, Jeggo R, Jhamandas JH, Kann O, la Cour CM, Martin WF, Mithieux G, Moreira PI, Murphy MP, Nave KA, Nuriel T, Oliet SHR, Saudou F, Mattson MP, Swerdlow RH, Millan MJ. Brain energy rescue: an emerging therapeutic concept for neurodegenerative disorders of ageing. Nat Rev Drug Discov 2020; 19:609-633. [PMID: 32709961 PMCID: PMC7948516 DOI: 10.1038/s41573-020-0072-x] [Citation(s) in RCA: 383] [Impact Index Per Article: 95.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/03/2020] [Indexed: 12/11/2022]
Abstract
The brain requires a continuous supply of energy in the form of ATP, most of which is produced from glucose by oxidative phosphorylation in mitochondria, complemented by aerobic glycolysis in the cytoplasm. When glucose levels are limited, ketone bodies generated in the liver and lactate derived from exercising skeletal muscle can also become important energy substrates for the brain. In neurodegenerative disorders of ageing, brain glucose metabolism deteriorates in a progressive, region-specific and disease-specific manner - a problem that is best characterized in Alzheimer disease, where it begins presymptomatically. This Review discusses the status and prospects of therapeutic strategies for countering neurodegenerative disorders of ageing by improving, preserving or rescuing brain energetics. The approaches described include restoring oxidative phosphorylation and glycolysis, increasing insulin sensitivity, correcting mitochondrial dysfunction, ketone-based interventions, acting via hormones that modulate cerebral energetics, RNA therapeutics and complementary multimodal lifestyle changes.
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Affiliation(s)
- Stephen C Cunnane
- Department of Medicine, Université de Sherbrooke, Sherbrooke, QC, Canada.
- Research Center on Aging, Sherbrooke, QC, Canada.
| | | | - Cecilie Morland
- Department of Pharmaceutical Biosciences, Institute of Pharmacy, University of Oslo, Oslo, Norway
| | - Alessandro Prigione
- Department of General Pediatrics, Neonatology, and Pediatric Cardiology, University of Dusseldorf, Dusseldorf, Germany
| | - Gemma Casadesus
- Department of Biological Sciences, Kent State University, Kent, OH, USA
| | - Zane B Andrews
- Monash Biomedicine Discovery Institute, Monash University, Clayton, VIC, Australia
- Department of Physiology, Monash University, Clayton, VIC, Australia
| | - M Flint Beal
- Department of Neurology, Weill Cornell Medicine, New York, NY, USA
| | - Linda H Bergersen
- Department of Anatomy, Institute of Basic Medical Sciences, University of Oslo, Oslo, Norway
| | | | | | | | - Jenni Harvey
- Ninewells Hospital, University of Dundee, Dundee, UK
- Medical School, University of Dundee, Dundee, UK
| | - Ross Jeggo
- Centre for Therapeutic Innovation in Neuropsychiatry, Institut de Recherche Servier, Croissy sur Seine, France
| | - Jack H Jhamandas
- Department of Medicine, University of Albeta, Edmonton, AB, Canada
- Neuroscience and Mental Health Institute, University of Albeta, Edmonton, AB, Canada
| | - Oliver Kann
- Institute of Physiology and Pathophysiology, University of Heidelberg, Heidelberg, Germany
| | - Clothide Mannoury la Cour
- Centre for Therapeutic Innovation in Neuropsychiatry, Institut de Recherche Servier, Croissy sur Seine, France
| | - William F Martin
- Institute of Molecular Evolution, University of Dusseldorf, Dusseldorf, Germany
| | | | - Paula I Moreira
- CNC Center for Neuroscience and Cell Biology, University of Coimbra, Coimbra, Portugal
- Faculty of Medicine, University of Coimbra, Coimbra, Portugal
| | - Michael P Murphy
- MRC Mitochondrial Biology Unit, University of Cambridge, Cambridge, UK
| | - Klaus-Armin Nave
- Department of Biosciences, University of Heidelberg, Heidelberg, Germany
| | - Tal Nuriel
- Columbia University Medical Center, New York, NY, USA
| | - Stéphane H R Oliet
- Neurocentre Magendie, INSERM U1215, Bordeaux, France
- Université de Bordeaux, Bordeaux, France
| | - Frédéric Saudou
- University of Grenoble Alpes, Grenoble, France
- INSERM U1216, CHU Grenoble Alpes, Grenoble Institute Neurosciences, Grenoble, France
| | - Mark P Mattson
- Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | | | - Mark J Millan
- Centre for Therapeutic Innovation in Neuropsychiatry, Institut de Recherche Servier, Croissy sur Seine, France.
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5
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Gilmour BC, Gudmundsrud R, Frank J, Hov A, Lautrup S, Aman Y, Røsjø H, Brenner C, Ziegler M, Tysnes OB, Tzoulis C, Omland T, Søraas A, Holmøy T, Bergersen LH, Storm-Mathisen J, Nilsen H, Fang EF. Targeting NAD + in translational research to relieve diseases and conditions of metabolic stress and ageing. Mech Ageing Dev 2020; 186:111208. [PMID: 31953124 DOI: 10.1016/j.mad.2020.111208] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2019] [Revised: 01/10/2020] [Accepted: 01/13/2020] [Indexed: 02/07/2023]
Abstract
Nicotinamide adenine dinucleotide (NAD+) plays a fundamental role in life and health through the regulation of energy biogenesis, redox homeostasis, cell metabolism, and the arbitration of cell survival via linkages to apoptosis and autophagic pathways. The importance of NAD+ in ageing and healthy longevity has been revealed from laboratory animal studies and early-stage clinical testing. While basic researchers and clinicians have investigated the molecular mechanisms and translation potential of NAD+, there are still major gaps in applying laboratory science to design the most effective trials. This mini-review was based on the programme and discussions of the 3rd NO-Age Symposium held at the Akershus University Hospital, Norway on the 28th October 2019. This symposium brought together leading basic researchers on NAD+ and clinicians who are leading or are going to perform NAD+ augmentation-related clinical studies. This meeting covered talks about NAD+ synthetic pathways, subcellular homeostasis of NAD+, the benefits of NAD+ augmentation from maternal milk to offspring, current clinical trials of the NAD+ precursor nicotinamide riboside (NR) on Ataxia-Telangiectasia (A-T), Parkinson's disease (PD), post-sepsis fatigue, as well as other potential NR-based clinical trials. Importantly, a consensus is emerging with respect to the design of clinical trials in order to measure meaningful parameters and ensure safety.
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Affiliation(s)
- Brian C Gilmour
- The Norwegian Centre on Healthy Ageing (NO-Age), Oslo, Norway
| | | | - Johannes Frank
- Department of Clinical Molecular Biology, University of Oslo and Akershus University Hospital, 1478 Lørenskog, Norway
| | - Amund Hov
- The Norwegian Centre on Healthy Ageing (NO-Age), Oslo, Norway
| | - Sofie Lautrup
- Department of Clinical Molecular Biology, University of Oslo and Akershus University Hospital, 1478 Lørenskog, Norway
| | - Yahyah Aman
- Department of Clinical Molecular Biology, University of Oslo and Akershus University Hospital, 1478 Lørenskog, Norway
| | - Helge Røsjø
- Division of Research and Innovation, Akershus University Hospital, 1478 Lørenskog, Norway; Institute for Clinical Medicine, University of Oslo, Oslo, Norway
| | - Charles Brenner
- Department of Biochemistry, Carver College of Medicine, University of Iowa, Iowa City, IA, USA
| | - Mathias Ziegler
- Department of Biomedicine, University of Bergen, 5009 Bergen, Norway
| | - Ole-Bjørn Tysnes
- Neuro-SysMed, Department of Neurology, Haukeland University Hospital, 5021 Bergen, Norway; Department of Clinical Medicine, University of Bergen, Bergen, Norway
| | - Charalampos Tzoulis
- Neuro-SysMed, Department of Neurology, Haukeland University Hospital, 5021 Bergen, Norway; Department of Clinical Medicine, University of Bergen, Bergen, Norway
| | - Torbjørn Omland
- Institute for Clinical Medicine, University of Oslo, Oslo, Norway; Department of Cardiology, Division of Medicine, Akershus University Hospital, 1478 Lørenskog, Norway
| | - Arne Søraas
- Department of Microbiology, Oslo University Hospital, Oslo, Norway
| | - Trygve Holmøy
- Department of Neurology, Akershus University Hospital, Lørenskog, Norway; Department of Clinical Medicine, University of Oslo, Oslo, Norway
| | - Linda H Bergersen
- The Norwegian Centre on Healthy Ageing (NO-Age), Oslo, Norway; The Brain and Muscle Energy Group, Electron Microscopy Laboratory, Department of Oral Biology, University of Oslo, NO-0316 Oslo, Norway; Synaptic Neurochemistry and Amino Acid Transporters Labs, Division of Anatomy, Department of Molecular Medicine, Institute of Basic Medical Sciences (IMB) and Healthy Brain Ageing Centre (SERTA), University of Oslo, NO-0317 Oslo, Norway; Center for Healthy Ageing, Department of Neuroscience and Pharmacology, Faculty of Health Sciences, University of Copenhagen, DK-2200 Copenhagen N, Denmark
| | - Jon Storm-Mathisen
- The Norwegian Centre on Healthy Ageing (NO-Age), Oslo, Norway; Synaptic Neurochemistry and Amino Acid Transporters Labs, Division of Anatomy, Department of Molecular Medicine, Institute of Basic Medical Sciences (IMB) and Healthy Brain Ageing Centre (SERTA), University of Oslo, NO-0317 Oslo, Norway
| | - Hilde Nilsen
- Department of Clinical Molecular Biology, University of Oslo and Akershus University Hospital, 1478 Lørenskog, Norway; The Norwegian Centre on Healthy Ageing (NO-Age), Oslo, Norway
| | - Evandro F Fang
- Department of Clinical Molecular Biology, University of Oslo and Akershus University Hospital, 1478 Lørenskog, Norway; The Norwegian Centre on Healthy Ageing (NO-Age), Oslo, Norway.
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6
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Haugen ØP, Vallenari EM, Belhaj I, Småstuen MC, Storm-Mathisen J, Bergersen LH, Åmellem I. Blood lactate dynamics in awake and anaesthetized mice after intraperitoneal and subcutaneous injections of lactate-sex matters. PeerJ 2020; 8:e8328. [PMID: 31934509 PMCID: PMC6951280 DOI: 10.7717/peerj.8328] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2019] [Accepted: 12/02/2019] [Indexed: 11/20/2022] Open
Abstract
Lactate treatment has shown a therapeutic potential for several neurological diseases, including Alzheimer's disease. In order to optimize the administration of lactate for studies in mouse models, we compared blood lactate dynamics after intraperitoneal (IP) and subcutaneous (SC) injections. We used the 5xFAD mouse model for familial Alzheimer's disease and performed the experiments in both awake and anaesthetized mice. Blood glucose was used as an indication of the hepatic conversion of lactate. In awake mice, both injection routes resulted in high blood lactate levels, mimicking levels reached during high-intensity training. In anaesthetized mice, SC injections resulted in significantly lower lactate levels compared to IP injections. Interestingly, we observed that awake males had significantly higher lactate levels than awake females, while the opposite sex difference was observed during anaesthesia. We did not find any significant difference between transgenic and wild-type mice and therefore believe that our results can be generalized to other mouse models. These results should be considered when planning experiments using lactate treatment in mice.
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Affiliation(s)
- Øyvind P Haugen
- The Brain and Muscle Energy Group, Electron Microscopy Laboratory, Institute of Oral Biology, University of Oslo, Oslo, Norway
| | - Evan M Vallenari
- The Brain and Muscle Energy Group, Electron Microscopy Laboratory, Institute of Oral Biology, University of Oslo, Oslo, Norway
| | - Imen Belhaj
- The Brain and Muscle Energy Group, Electron Microscopy Laboratory, Institute of Oral Biology, University of Oslo, Oslo, Norway.,Amino Acid Transporter Laboratory, Division of Anatomy, Department of Molecular Medicine, Institute of Basic Medical Sciences, SERTA: Healthy Brain Ageing Centre, University of Oslo, Oslo, Norway
| | - Milada Cvancarova Småstuen
- Department of Nursing and Health Promotion, Faculty of Health Science, Oslo Metropolitan University, Oslo, Norway
| | - Jon Storm-Mathisen
- Amino Acid Transporter Laboratory, Division of Anatomy, Department of Molecular Medicine, Institute of Basic Medical Sciences, SERTA: Healthy Brain Ageing Centre, University of Oslo, Oslo, Norway
| | - Linda H Bergersen
- The Brain and Muscle Energy Group, Electron Microscopy Laboratory, Institute of Oral Biology, University of Oslo, Oslo, Norway
| | - Ingrid Åmellem
- The Brain and Muscle Energy Group, Electron Microscopy Laboratory, Institute of Oral Biology, University of Oslo, Oslo, Norway
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7
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Aman Y, Frank J, Lautrup SH, Matysek A, Niu Z, Yang G, Shi L, Bergersen LH, Storm-Mathisen J, Rasmussen LJ, Bohr VA, Nilsen H, Fang EF. The NAD +-mitophagy axis in healthy longevity and in artificial intelligence-based clinical applications. Mech Ageing Dev 2020; 185:111194. [PMID: 31812486 PMCID: PMC7545219 DOI: 10.1016/j.mad.2019.111194] [Citation(s) in RCA: 31] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2019] [Revised: 11/24/2019] [Accepted: 12/03/2019] [Indexed: 12/11/2022]
Abstract
Nicotinamide adenine dinucleotide (NAD+) is an important natural molecule involved in fundamental biological processes, including the TCA cycle, OXPHOS, β-oxidation, and is a co-factor for proteins promoting healthy longevity. NAD+ depletion is associated with the hallmarks of ageing and may contribute to a wide range of age-related diseases including metabolic disorders, cancer, and neurodegenerative diseases. One of the central pathways by which NAD+ promotes healthy ageing is through regulation of mitochondrial homeostasis via mitochondrial biogenesis and the clearance of damaged mitochondria via mitophagy. Here, we highlight the contribution of the NAD+-mitophagy axis to ageing and age-related diseases, and evaluate how boosting NAD+ levels may emerge as a promising therapeutic strategy to counter ageing as well as neurodegenerative diseases including Alzheimer's disease. The potential use of artificial intelligence to understand the roles and molecular mechanisms of the NAD+-mitophagy axis in ageing is discussed, including possible applications in drug target identification and validation, compound screening and lead compound discovery, biomarker development, as well as efficacy and safety assessment. Advances in our understanding of the molecular and cellular roles of NAD+ in mitophagy will lead to novel approaches for facilitating healthy mitochondrial homoeostasis that may serve as a promising therapeutic strategy to counter ageing-associated pathologies and/or accelerated ageing.
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Affiliation(s)
- Yahyah Aman
- Department of Clinical Molecular Biology, University of Oslo and Akershus University Hospital, 1478, Lørenskog, Norway
| | - Johannes Frank
- Department of Clinical Molecular Biology, University of Oslo and Akershus University Hospital, 1478, Lørenskog, Norway
| | - Sofie Hindkjær Lautrup
- Department of Clinical Molecular Biology, University of Oslo and Akershus University Hospital, 1478, Lørenskog, Norway
| | - Adrian Matysek
- Department of Clinical Molecular Biology, University of Oslo and Akershus University Hospital, 1478, Lørenskog, Norway; School of Pharmacy and Division of Laboratory Medicine in Sosnowiec, Medical University of Silesia in Katowice, 40-055, Katowice, Poland
| | - Zhangming Niu
- Aladdin Healthcare Technologies Ltd., 24-26 Baltic Street West, London, EC1Y OUR, UK
| | - Guang Yang
- Cardiovascular Research Centre, Royal Brompton Hospital, London, SW3 6NP, UK; National Heart and Lung Institute, Imperial College London, London, SW7 2AZ, UK
| | - Liu Shi
- Department of Psychiatry, University of Oxford, Oxford, UK
| | - Linda H Bergersen
- The Brain and Muscle Energy Group, Electron Microscopy Laboratory, Department of Oral Biology, University of Oslo, NO-0316, Oslo, Norway; Amino Acid Transporters, Division of Anatomy, Department of Molecular Medicine, Institute of Basic Medical Sciences (IMB) and Healthy Brain Ageing Centre (SERTA), University of Oslo, NO-0317, Oslo, Norway; Center for Healthy Aging, Department of Neuroscience and Pharmacology, Faculty of Health Sciences, University of Copenhagen, DK-2200, Copenhagen N, Denmark; The Norwegian Centre on Healthy Ageing (NO-Age), Oslo, Norway
| | - Jon Storm-Mathisen
- Amino Acid Transporters, Division of Anatomy, Department of Molecular Medicine, Institute of Basic Medical Sciences (IMB) and Healthy Brain Ageing Centre (SERTA), University of Oslo, NO-0317, Oslo, Norway; The Norwegian Centre on Healthy Ageing (NO-Age), Oslo, Norway
| | - Lene J Rasmussen
- The Norwegian Centre on Healthy Ageing (NO-Age), Oslo, Norway; Center for Healthy Aging, Department of Cellular and Molecular Medicine, Faculty of Health Sciences, University of Copenhagen, DK-2200, Copenhagen N, Denmark
| | - Vilhelm A Bohr
- Laboratory of Molecular Gerontology, National Institute on Aging, National Institutes of Health, Baltimore, MD, 21224, United States; The Norwegian Centre on Healthy Ageing (NO-Age), Oslo, Norway; Center for Healthy Aging, Department of Cellular and Molecular Medicine, Faculty of Health Sciences, University of Copenhagen, DK-2200, Copenhagen N, Denmark
| | - Hilde Nilsen
- Department of Clinical Molecular Biology, University of Oslo and Akershus University Hospital, 1478, Lørenskog, Norway; The Norwegian Centre on Healthy Ageing (NO-Age), Oslo, Norway
| | - Evandro F Fang
- Department of Clinical Molecular Biology, University of Oslo and Akershus University Hospital, 1478, Lørenskog, Norway; The Norwegian Centre on Healthy Ageing (NO-Age), Oslo, Norway.
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8
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Vohra R, Aldana BI, Waagepetersen H, Bergersen LH, Kolko M. Dual Properties of Lactate in Müller Cells: The Effect of GPR81 Activation. Invest Ophthalmol Vis Sci 2019; 60:999-1008. [PMID: 30884529 DOI: 10.1167/iovs.18-25458] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Purpose Besides being actively metabolized, lactate may also function as a signaling molecule by activation of the G-protein-coupled receptor 81 (GPR81). Thus, we aimed to characterize the metabolic effects of GPR81 activation in Müller cells. Method Primary Müller cells from mice were treated with and without 10 mM L-lactate in the presence or absence of 6 mM glucose. The effects of lactate receptor GPR81 activation were evaluated by the addition of 5 mM 3,5-DHBA (3,5-dihydroxybenzoic acid), a GPR81 agonist. Western blot analyses were used to determine protein expression of GPR81. Cell survival was assessed through 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) viability assays. Lactate release was quantified by commercially available lactate kits. 13C-labeling studies via mass spectroscopy and Seahorse analyses were performed to evaluate metabolism of lactate and glucose, and mitochondrial function. Finally, Müller cell function was evaluated by measuring glutamate uptake. Results The lactate receptor, GPR81, was upregulated during glucose deprivation. Treatment with a GPR81 agonist did not affect Müller cell survival. However, GPR81 activation diminished lactate release allowing lactate to be metabolized intracellularly. Furthermore, GPR81 activation increased metabolism of glucose and mitochondrial function. Finally, maximal glutamate uptake decreased in response to GPR81 activation during glucose deprivation. Conclusions The present study revealed dual properties of lactate via functioning as an active metabolic energy substrate and a regulatory molecule by activation of the GPR81 receptor in primary Müller cells. Thus, combinational therapy of lactate and GPR81 agonists may be of future interest in maintaining Müller cell survival, ultimately leading to increased resistance toward retinal neurodegeneration.
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Affiliation(s)
- Rupali Vohra
- Department of Drug Design and Pharmacology, University of Copenhagen, Copenhagen, Denmark
| | - Blanca I Aldana
- Department of Drug Design and Pharmacology, University of Copenhagen, Copenhagen, Denmark
| | - Helle Waagepetersen
- Department of Drug Design and Pharmacology, University of Copenhagen, Copenhagen, Denmark
| | - Linda H Bergersen
- Center of Healthy Aging, University of Copenhagen, Copenhagen, Denmark.,Brain and Muscle Energy Group, Faculty of Dentistry, Institute of Oral Biology, University of Oslo, Oslo, Norway
| | - Miriam Kolko
- Department of Drug Design and Pharmacology, University of Copenhagen, Copenhagen, Denmark.,Department of Ophthalmology, Rigshospitalet-Glostrup, Copenhagen, Denmark
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9
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Tari AR, Norevik CS, Scrimgeour NR, Kobro-Flatmoen A, Storm-Mathisen J, Bergersen LH, Wrann CD, Selbæk G, Kivipelto M, Moreira JBN, Wisløff U. Are the neuroprotective effects of exercise training systemically mediated? Prog Cardiovasc Dis 2019; 62:94-101. [PMID: 30802460 DOI: 10.1016/j.pcad.2019.02.003] [Citation(s) in RCA: 62] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/21/2019] [Accepted: 02/21/2019] [Indexed: 02/06/2023]
Abstract
To date there is no cure available for dementia, and the field calls for novel therapeutic targets. A rapidly growing body of literature suggests that regular endurance training and high cardiorespiratory fitness attenuate cognitive impairment and reduce dementia risk. Such benefits have recently been linked to systemic neurotrophic factors induced by exercise. These circulating biomolecules may cross the blood-brain barrier and potentially protect against neurodegenerative disorders such as Alzheimer's disease. Identifying exercise-induced systemic neurotrophic factors with beneficial effects on the brain may lead to novel molecular targets for maintaining cognitive function and preventing neurodegeneration. Here we review the recent literature on potential systemic mediators of neuroprotection induced by exercise. We focus on the body of translational research in the field, integrating knowledge from the molecular level, animal models, clinical and epidemiological studies. Taken together, the current literature provides initial evidence that exercise-induced, blood-borne biomolecules, such as BDNF and FNDC5/irisin, may be powerful agents mediating the benefits of exercise on cognitive function and may form the basis for new therapeutic strategies to better prevent and treat dementia.
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Affiliation(s)
- Atefe R Tari
- The Cardiac Exercise Research Group at Department of Circulation and Medical Imaging, The Norwegian University of Science and Technology, Norway; Department of Neurology, St. Olavs Hospital, Trondheim, Norway.
| | - Cecilie S Norevik
- The Cardiac Exercise Research Group at Department of Circulation and Medical Imaging, The Norwegian University of Science and Technology, Norway; Department of Neurology, St. Olavs Hospital, Trondheim, Norway
| | - Nathan R Scrimgeour
- The Cardiac Exercise Research Group at Department of Circulation and Medical Imaging, The Norwegian University of Science and Technology, Norway
| | - Asgeir Kobro-Flatmoen
- Kavli Institute for Systems Neuroscience, Centre for Neural Computation, Egil and Pauline Braathen and Fred Kavli Centre for Cortical Microcircuits, Norwegian University of Science and Technology, Norway
| | | | | | - Christiane D Wrann
- Massachusetts General Hospital and Harvard Medical School, Henry and Allison McCance Center for Brain Health, Massachusetts General Hospital, Boston, MA, United States of America
| | - Geir Selbæk
- Norwegian National Advisory Unit on Ageing and Health, Vestfold Hospital Trust, Tønsberg, Norway; Institute of Health and Society, Faculty of Medicine, University of Oslo, Oslo, Norway; Research Centre for Age-related Functional Decline and Disease, Innlandet Hospital Trust, Ottestad, Norway
| | - Miia Kivipelto
- Division of Clinical Geriatrics, Center for Alzheimer Research, Karolinska Institute, Stockholm, Sweden; Department of Neurology, Institute of Clinical Medicine, University of Eastern Finland, Kuopio, Finland; Age and Epidemiology Research Unit, School of Public Health, Imperial College London, UK
| | - José Bianco N Moreira
- The Cardiac Exercise Research Group at Department of Circulation and Medical Imaging, The Norwegian University of Science and Technology, Norway
| | - Ulrik Wisløff
- The Cardiac Exercise Research Group at Department of Circulation and Medical Imaging, The Norwegian University of Science and Technology, Norway
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10
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11
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Hasan-Olive MM, Lauritzen KH, Ali M, Rasmussen LJ, Storm-Mathisen J, Bergersen LH. A Ketogenic Diet Improves Mitochondrial Biogenesis and Bioenergetics via the PGC1α-SIRT3-UCP2 Axis. Neurochem Res 2018; 44:22-37. [PMID: 30027365 DOI: 10.1007/s11064-018-2588-6] [Citation(s) in RCA: 97] [Impact Index Per Article: 16.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2018] [Revised: 06/20/2018] [Accepted: 06/24/2018] [Indexed: 11/30/2022]
Abstract
A ketogenic diet (KD; high-fat, low-carbohydrate) can benefit refractory epilepsy, but underlying mechanisms are unknown. We used mice inducibly expressing a mutated form of the mitochondrial DNA repair enzyme UNG1 (mutUNG1) to cause progressive mitochondrial dysfunction selectively in forebrain neurons. We examined the levels of mRNAs and proteins crucial for mitochondrial biogenesis and dynamics. We show that hippocampal pyramidal neurons in mutUNG1 mice, as well as cultured rat hippocampal neurons and human fibroblasts with H2O2 induced oxidative stress, improve markers of mitochondrial biogenesis, dynamics and function when fed on a KD, and when exposed to the ketone body β-hydroxybutyrate, respectively, by upregulating PGC1α, SIRT3 and UCP2, and (in cultured cells) increasing the oxygen consumption rate (OCR) and the NAD+/NADH ratio. The mitochondrial level of UCP2 was significantly higher in the perikarya and axon terminals of hippocampus CA1 pyramidal neurons in KD treated mutUNG1 mice compared with mutUNG1 mice fed a standard diet. The β-hydroxybutyrate receptor GPR109a (HCAR2), but not the structurally closely related lactate receptor GPR81 (HCAR1), was upregulated in mutUNG1 mice on a KD, suggesting a selective influence of KD on ketone body receptor mechanisms. We conclude that progressive mitochondrial dysfunction in mutUNG1 expressing mice causes oxidative stress, and that exposure of animals to KD, or of cells to ketone body in vitro, elicits compensatory mechanisms acting to augment mitochondrial mass and bioenergetics via the PGC1α-SIRT3-UCP2 axis (The compensatory processes are overwhelmed in the mutUNG1 mice by all the newly formed mitochondria being dysfunctional).
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Affiliation(s)
- Md Mahdi Hasan-Olive
- Synaptic Neurochemistry and Amino Acid Transporter Laboratory, Division of Anatomy and CMBN/SERTA Healthy Brain Ageing Center, Institute of Basic Medical Sciences, University of Oslo, Oslo, Norway. .,Brain and Muscle Energy Group, Electron Microscopy Laboratory, Institute of Oral Biology, University of Oslo, Oslo, Norway. .,Center for Healthy Aging, Department of Neurosciences and Pharmacology, Faculty of Health Sciences, University of Copenhagen, Copenhagen, Denmark.
| | - Knut H Lauritzen
- Synaptic Neurochemistry and Amino Acid Transporter Laboratory, Division of Anatomy and CMBN/SERTA Healthy Brain Ageing Center, Institute of Basic Medical Sciences, University of Oslo, Oslo, Norway.,Research Institute of Internal Medicine, Oslo University Hospital Rikshospitalet, Oslo, Norway
| | - Mohammad Ali
- Department of Biochemistry, Sir Salimullah Medical College & Mitford Hospital, Dhaka, Bangladesh
| | - Lene Juel Rasmussen
- Center for Healthy Aging, Department of Neurosciences and Pharmacology, Faculty of Health Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Jon Storm-Mathisen
- Synaptic Neurochemistry and Amino Acid Transporter Laboratory, Division of Anatomy and CMBN/SERTA Healthy Brain Ageing Center, Institute of Basic Medical Sciences, University of Oslo, Oslo, Norway
| | - Linda H Bergersen
- Synaptic Neurochemistry and Amino Acid Transporter Laboratory, Division of Anatomy and CMBN/SERTA Healthy Brain Ageing Center, Institute of Basic Medical Sciences, University of Oslo, Oslo, Norway. .,Brain and Muscle Energy Group, Electron Microscopy Laboratory, Institute of Oral Biology, University of Oslo, Oslo, Norway. .,Center for Healthy Aging, Department of Neurosciences and Pharmacology, Faculty of Health Sciences, University of Copenhagen, Copenhagen, Denmark.
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12
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Vardjan N, Chowdhury HH, Horvat A, Velebit J, Malnar M, Muhič M, Kreft M, Krivec ŠG, Bobnar ST, Miš K, Pirkmajer S, Offermanns S, Henriksen G, Storm-Mathisen J, Bergersen LH, Zorec R. Enhancement of Astroglial Aerobic Glycolysis by Extracellular Lactate-Mediated Increase in cAMP. Front Mol Neurosci 2018; 11:148. [PMID: 29867342 PMCID: PMC5953330 DOI: 10.3389/fnmol.2018.00148] [Citation(s) in RCA: 56] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2018] [Accepted: 04/16/2018] [Indexed: 11/13/2022] Open
Abstract
Besides being a neuronal fuel, L-lactate is also a signal in the brain. Whether extracellular L-lactate affects brain metabolism, in particular astrocytes, abundant neuroglial cells, which produce L-lactate in aerobic glycolysis, is unclear. Recent studies suggested that astrocytes express low levels of the L-lactate GPR81 receptor (EC50 ≈ 5 mM) that is in fat cells part of an autocrine loop, in which the Gi-protein mediates reduction of cytosolic cyclic adenosine monophosphate (cAMP). To study whether a similar signaling loop is present in astrocytes, affecting aerobic glycolysis, we measured the cytosolic levels of cAMP, D-glucose and L-lactate in single astrocytes using fluorescence resonance energy transfer (FRET)-based nanosensors. In contrast to the situation in fat cells, stimulation by extracellular L-lactate and the selective GPR81 agonists, 3-chloro-5-hydroxybenzoic acid (3Cl-5OH-BA) or 4-methyl-N-(5-(2-(4-methylpiperazin-1-yl)-2-oxoethyl)-4-(2-thienyl)-1,3-thiazol-2-yl)cyclohexanecarboxamide (Compound 2), like adrenergic stimulation, elevated intracellular cAMP and L-lactate in astrocytes, which was reduced by the inhibition of adenylate cyclase. Surprisingly, 3Cl-5OH-BA and Compound 2 increased cytosolic cAMP also in GPR81-knock out astrocytes, indicating that the effect is GPR81-independent and mediated by a novel, yet unidentified, excitatory L-lactate receptor-like mechanism in astrocytes that enhances aerobic glycolysis and L-lactate production via a positive feedback mechanism.
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Affiliation(s)
- Nina Vardjan
- Laboratory of Neuroendocrinology - Molecular Cell Physiology, Institute of Pathophysiology, Faculty of Medicine, University of Ljubljana, Ljubljana, Slovenia.,Laboratory of Cell Engineering, Celica Biomedical, Ljubljana, Slovenia
| | - Helena H Chowdhury
- Laboratory of Neuroendocrinology - Molecular Cell Physiology, Institute of Pathophysiology, Faculty of Medicine, University of Ljubljana, Ljubljana, Slovenia.,Laboratory of Cell Engineering, Celica Biomedical, Ljubljana, Slovenia
| | - Anemari Horvat
- Laboratory of Neuroendocrinology - Molecular Cell Physiology, Institute of Pathophysiology, Faculty of Medicine, University of Ljubljana, Ljubljana, Slovenia
| | - Jelena Velebit
- Laboratory of Neuroendocrinology - Molecular Cell Physiology, Institute of Pathophysiology, Faculty of Medicine, University of Ljubljana, Ljubljana, Slovenia.,Laboratory of Cell Engineering, Celica Biomedical, Ljubljana, Slovenia
| | - Maja Malnar
- Laboratory of Cell Engineering, Celica Biomedical, Ljubljana, Slovenia
| | - Marko Muhič
- Laboratory of Neuroendocrinology - Molecular Cell Physiology, Institute of Pathophysiology, Faculty of Medicine, University of Ljubljana, Ljubljana, Slovenia
| | - Marko Kreft
- Laboratory of Neuroendocrinology - Molecular Cell Physiology, Institute of Pathophysiology, Faculty of Medicine, University of Ljubljana, Ljubljana, Slovenia.,Laboratory of Cell Engineering, Celica Biomedical, Ljubljana, Slovenia.,Department of Biology, Biotechnical Faculty, University of Ljubljana, Ljubljana, Slovenia
| | - Špela G Krivec
- Laboratory of Neuroendocrinology - Molecular Cell Physiology, Institute of Pathophysiology, Faculty of Medicine, University of Ljubljana, Ljubljana, Slovenia.,Laboratory of Cell Engineering, Celica Biomedical, Ljubljana, Slovenia
| | - Saša T Bobnar
- Laboratory of Neuroendocrinology - Molecular Cell Physiology, Institute of Pathophysiology, Faculty of Medicine, University of Ljubljana, Ljubljana, Slovenia.,Laboratory of Cell Engineering, Celica Biomedical, Ljubljana, Slovenia
| | - Katarina Miš
- Laboratory for Molecular Neurobiology, Institute of Pathophysiology, Faculty of Medicine, University of Ljubljana, Ljubljana, Slovenia
| | - Sergej Pirkmajer
- Laboratory for Molecular Neurobiology, Institute of Pathophysiology, Faculty of Medicine, University of Ljubljana, Ljubljana, Slovenia
| | - Stefan Offermanns
- Department of Pharmacology, Max Planck Institute for Heart and Lung Research, Bad Nauheim, Germany
| | - Gjermund Henriksen
- Nuclear and Energy Physics, Department of Physics, The Faculty of Mathematics and Natural Sciences, University of Oslo, Oslo, Norway.,Norwegian Medical Cyclotron Centre Ltd., Oslo, Norway
| | - Jon Storm-Mathisen
- Division of Anatomy, Department of Molecular Medicine, CMBN/SERTA Healthy Brain Ageing Centre, Institute of Basic Medical Sciences, Faculty of Medicine, University of Oslo, Oslo, Norway
| | - Linda H Bergersen
- Institute of Oral Biology, Faculty of Dentistry, University of Oslo, Oslo, Norway.,Center for Healthy Aging, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Robert Zorec
- Laboratory of Neuroendocrinology - Molecular Cell Physiology, Institute of Pathophysiology, Faculty of Medicine, University of Ljubljana, Ljubljana, Slovenia.,Laboratory of Cell Engineering, Celica Biomedical, Ljubljana, Slovenia
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13
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Morland C, Andersson KA, Haugen ØP, Hadzic A, Kleppa L, Gille A, Rinholm JE, Palibrk V, Diget EH, Kennedy LH, Stølen T, Hennestad E, Moldestad O, Cai Y, Puchades M, Offermanns S, Vervaeke K, Bjørås M, Wisløff U, Storm-Mathisen J, Bergersen LH. Exercise induces cerebral VEGF and angiogenesis via the lactate receptor HCAR1. Nat Commun 2017; 8:15557. [PMID: 28534495 PMCID: PMC5457513 DOI: 10.1038/ncomms15557] [Citation(s) in RCA: 263] [Impact Index Per Article: 37.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2016] [Accepted: 04/07/2017] [Indexed: 12/13/2022] Open
Abstract
Physical exercise can improve brain function and delay neurodegeneration; however, the initial signal from muscle to brain is unknown. Here we show that the lactate receptor (HCAR1) is highly enriched in pial fibroblast-like cells that line the vessels supplying blood to the brain, and in pericyte-like cells along intracerebral microvessels. Activation of HCAR1 enhances cerebral vascular endothelial growth factor A (VEGFA) and cerebral angiogenesis. High-intensity interval exercise (5 days weekly for 7 weeks), as well as L-lactate subcutaneous injection that leads to an increase in blood lactate levels similar to exercise, increases brain VEGFA protein and capillary density in wild-type mice, but not in knockout mice lacking HCAR1. In contrast, skeletal muscle shows no vascular HCAR1 expression and no HCAR1-dependent change in vascularization induced by exercise or lactate. Thus, we demonstrate that a substance released by exercising skeletal muscle induces supportive effects in brain through an identified receptor.
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MESH Headings
- Animals
- Brain/blood supply
- Capillaries/cytology
- Capillaries/drug effects
- Capillaries/metabolism
- Injections, Subcutaneous
- Lactic Acid/administration & dosage
- Lactic Acid/blood
- Lactic Acid/metabolism
- Male
- Mice
- Mice, Knockout
- Models, Animal
- Muscle, Skeletal/blood supply
- Muscle, Skeletal/drug effects
- Muscle, Skeletal/metabolism
- Neovascularization, Physiologic/physiology
- Pericytes/metabolism
- Physical Conditioning, Animal/physiology
- Receptors, G-Protein-Coupled/genetics
- Receptors, G-Protein-Coupled/metabolism
- Vascular Endothelial Growth Factor A/metabolism
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Affiliation(s)
- Cecilie Morland
- The Brain and Muscle Energy Group, Electron Microscopy Laboratory, Department of Oral Biology, University of Oslo, NO-0316 Oslo, Norway
- Institute for Behavioral Sciences, Faculty of Health Sciences, Oslo and Akershus University College, NO-0167 Oslo, Norway
- The Synaptic Neurochemistry Lab, Division of Anatomy, Department of Molecular Medicine, Institute of Basic Medical Sciences, Healthy Brain Ageing Centre, University of Oslo, NO-0317 Oslo, Norway
| | - Krister A. Andersson
- The Brain and Muscle Energy Group, Electron Microscopy Laboratory, Department of Oral Biology, University of Oslo, NO-0316 Oslo, Norway
- Institute for Behavioral Sciences, Faculty of Health Sciences, Oslo and Akershus University College, NO-0167 Oslo, Norway
- The Synaptic Neurochemistry Lab, Division of Anatomy, Department of Molecular Medicine, Institute of Basic Medical Sciences, Healthy Brain Ageing Centre, University of Oslo, NO-0317 Oslo, Norway
| | - Øyvind P. Haugen
- The Brain and Muscle Energy Group, Electron Microscopy Laboratory, Department of Oral Biology, University of Oslo, NO-0316 Oslo, Norway
| | - Alena Hadzic
- The Brain and Muscle Energy Group, Electron Microscopy Laboratory, Department of Oral Biology, University of Oslo, NO-0316 Oslo, Norway
- Institute for Behavioral Sciences, Faculty of Health Sciences, Oslo and Akershus University College, NO-0167 Oslo, Norway
- The Synaptic Neurochemistry Lab, Division of Anatomy, Department of Molecular Medicine, Institute of Basic Medical Sciences, Healthy Brain Ageing Centre, University of Oslo, NO-0317 Oslo, Norway
| | - Liv Kleppa
- The Brain and Muscle Energy Group, Electron Microscopy Laboratory, Department of Oral Biology, University of Oslo, NO-0316 Oslo, Norway
- The Synaptic Neurochemistry Lab, Division of Anatomy, Department of Molecular Medicine, Institute of Basic Medical Sciences, Healthy Brain Ageing Centre, University of Oslo, NO-0317 Oslo, Norway
| | - Andreas Gille
- Institute for Experimental and Clinical Pharmacology and Toxicology, Mannheim Medical Faculty, Heidelberg University, D-68169 Mannheim, Germany
| | - Johanne E. Rinholm
- The Brain and Muscle Energy Group, Electron Microscopy Laboratory, Department of Oral Biology, University of Oslo, NO-0316 Oslo, Norway
- The Synaptic Neurochemistry Lab, Division of Anatomy, Department of Molecular Medicine, Institute of Basic Medical Sciences, Healthy Brain Ageing Centre, University of Oslo, NO-0317 Oslo, Norway
| | - Vuk Palibrk
- Department of Cancer Research and Molecular Medicine, Norwegian University of Science and Technology, NO-7491 Trondheim, Norway
| | - Elisabeth H. Diget
- The Brain and Muscle Energy Group, Electron Microscopy Laboratory, Department of Oral Biology, University of Oslo, NO-0316 Oslo, Norway
- Center for Healthy Aging, Department of Neuroscience and Pharmacology, Faculty of Health Sciences, University of Copenhagen, DK-2200 Copenhagen N, Denmark
| | - Lauritz H. Kennedy
- The Brain and Muscle Energy Group, Electron Microscopy Laboratory, Department of Oral Biology, University of Oslo, NO-0316 Oslo, Norway
- The Synaptic Neurochemistry Lab, Division of Anatomy, Department of Molecular Medicine, Institute of Basic Medical Sciences, Healthy Brain Ageing Centre, University of Oslo, NO-0317 Oslo, Norway
| | - Tomas Stølen
- K.G. Jebsen Center of Exercise in Medicine, Department of Circulation and Medical Imaging, Norwegian University of Science and Technology, NO-7491 Trondheim, Norway
| | - Eivind Hennestad
- Laboratory of Neural Computation, Department of Physiology, University of Oslo, NO-0317 Oslo, Norway
| | - Olve Moldestad
- Centre for Rare Disorders, Oslo University Hospital, Rikshospitalet, NO-0424 Oslo, Norway
| | - Yiqing Cai
- The Brain and Muscle Energy Group, Electron Microscopy Laboratory, Department of Oral Biology, University of Oslo, NO-0316 Oslo, Norway
| | - Maja Puchades
- The Synaptic Neurochemistry Lab, Division of Anatomy, Department of Molecular Medicine, Institute of Basic Medical Sciences, Healthy Brain Ageing Centre, University of Oslo, NO-0317 Oslo, Norway
| | - Stefan Offermanns
- Max-Planck-Institute for Heart and Lung Research, Department of Pharmacology, D-61231 Bad Nauheim, Germany
| | - Koen Vervaeke
- Laboratory of Neural Computation, Department of Physiology, University of Oslo, NO-0317 Oslo, Norway
| | - Magnar Bjørås
- Department of Cancer Research and Molecular Medicine, Norwegian University of Science and Technology, NO-7491 Trondheim, Norway
| | - Ulrik Wisløff
- K.G. Jebsen Center of Exercise in Medicine, Department of Circulation and Medical Imaging, Norwegian University of Science and Technology, NO-7491 Trondheim, Norway
| | - Jon Storm-Mathisen
- The Synaptic Neurochemistry Lab, Division of Anatomy, Department of Molecular Medicine, Institute of Basic Medical Sciences, Healthy Brain Ageing Centre, University of Oslo, NO-0317 Oslo, Norway
| | - Linda H. Bergersen
- The Brain and Muscle Energy Group, Electron Microscopy Laboratory, Department of Oral Biology, University of Oslo, NO-0316 Oslo, Norway
- The Synaptic Neurochemistry Lab, Division of Anatomy, Department of Molecular Medicine, Institute of Basic Medical Sciences, Healthy Brain Ageing Centre, University of Oslo, NO-0317 Oslo, Norway
- Center for Healthy Aging, Department of Neuroscience and Pharmacology, Faculty of Health Sciences, University of Copenhagen, DK-2200 Copenhagen N, Denmark
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14
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Jensen J, Storm-Mathisen J, Bergersen LH, Wærhaug O, Samuelsen G, Osen KK. Minneord: Hans A. Dahl. Tidsskriftet 2017; 137:17-0487. [DOI: 10.4045/tidsskr.17.0487] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022] Open
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15
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Hamilton NB, Clarke LE, Arancibia-Carcamo IL, Kougioumtzidou E, Matthey M, Káradóttir R, Whiteley L, Bergersen LH, Richardson WD, Attwell D. Endogenous GABA controls oligodendrocyte lineage cell number, myelination, and CNS internode length. Glia 2016; 65:309-321. [PMID: 27796063 PMCID: PMC5214060 DOI: 10.1002/glia.23093] [Citation(s) in RCA: 66] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2015] [Revised: 10/07/2016] [Accepted: 10/11/2016] [Indexed: 11/30/2022]
Abstract
Adjusting the thickness and internodal length of the myelin sheath is a mechanism for tuning the conduction velocity of axons to match computational needs. Interactions between oligodendrocyte precursor cells (OPCs) and developing axons regulate the formation of myelin around axons. We now show, using organotypic cerebral cortex slices from mice expressing eGFP in Sox10‐positive oligodendrocytes, that endogenously released GABA, acting on GABAA receptors, greatly reduces the number of oligodendrocyte lineage cells. The decrease in oligodendrocyte number correlates with a reduction in the amount of myelination but also an increase in internode length, a parameter previously thought to be set by the axon diameter or to be a property intrinsic to oligodendrocytes. Importantly, while TTX block of neuronal activity had no effect on oligodendrocyte lineage cell number when applied alone, it was able to completely abolish the effect of blocking GABAA receptors, suggesting that control of myelination by endogenous GABA may require a permissive factor to be released from axons. In contrast, block of AMPA/KA receptors had no effect on oligodendrocyte lineage cell number or myelination. These results imply that, during development, GABA can act as a local environmental cue to control myelination and thus influence the conduction velocity of action potentials within the CNS. GLIA 2017;65:309–321
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Affiliation(s)
- Nicola B Hamilton
- Department of Neuroscience, Pharmacology and Physiology, University College London, London, WC1E 6BT, United Kingdom
| | - Laura E Clarke
- Department of Neuroscience, Pharmacology and Physiology, University College London, London, WC1E 6BT, United Kingdom
| | - I Lorena Arancibia-Carcamo
- Department of Neuroscience, Pharmacology and Physiology, University College London, London, WC1E 6BT, United Kingdom
| | - Eleni Kougioumtzidou
- Department of Cell and Developmental Biology, Wolfson Institute for Biomedical Research, University College London, London, WC1E 6BT, United Kingdom
| | - Moritz Matthey
- Wellcome Trust-MRC Cambridge Stem Cell Institute, Cambridge, CB2 1QR, United Kingdom
| | - Ragnhildur Káradóttir
- Wellcome Trust-MRC Cambridge Stem Cell Institute, Cambridge, CB2 1QR, United Kingdom
| | - Louise Whiteley
- Department of Neuroscience, Pharmacology and Physiology, University College London, London, WC1E 6BT, United Kingdom
| | - Linda H Bergersen
- Department of Oral Biology, Brain and Muscle Energy Group, University of Oslo, Blindern, Oslo, N-0317, Norway.,Department of Anatomy, University of Oslo, Blindern, Oslo, N-0317, Norway
| | - William D Richardson
- Department of Cell and Developmental Biology, Wolfson Institute for Biomedical Research, University College London, London, WC1E 6BT, United Kingdom
| | - David Attwell
- Department of Neuroscience, Pharmacology and Physiology, University College London, London, WC1E 6BT, United Kingdom
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16
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Lauritzen KH, Hasan-Olive MM, Regnell CE, Kleppa L, Scheibye-Knudsen M, Gjedde A, Klungland A, Bohr VA, Storm-Mathisen J, Bergersen LH. A ketogenic diet accelerates neurodegeneration in mice with induced mitochondrial DNA toxicity in the forebrain. Neurobiol Aging 2016; 48:34-47. [PMID: 27639119 DOI: 10.1016/j.neurobiolaging.2016.08.005] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2015] [Revised: 08/03/2016] [Accepted: 08/09/2016] [Indexed: 12/12/2022]
Abstract
Mitochondrial genome maintenance plays a central role in preserving brain health. We previously demonstrated accumulation of mitochondrial DNA damage and severe neurodegeneration in transgenic mice inducibly expressing a mutated mitochondrial DNA repair enzyme (mutUNG1) selectively in forebrain neurons. Here, we examine whether severe neurodegeneration in mutUNG1-expressing mice could be rescued by feeding the mice a ketogenic diet, which is known to have beneficial effects in several neurological disorders. The diet increased the levels of superoxide dismutase 2, and mitochondrial mass, enzymes, and regulators such as SIRT1 and FIS1, and appeared to downregulate N-methyl-D-aspartic acid (NMDA) receptor subunits NR2A/B and upregulate γ-aminobutyric acid A (GABAA) receptor subunits α1. However, unexpectedly, the ketogenic diet aggravated neurodegeneration and mitochondrial deterioration. Electron microscopy showed structurally impaired mitochondria accumulating in neuronal perikarya. We propose that aggravation is caused by increased mitochondrial biogenesis of generally dysfunctional mitochondria. This study thereby questions the dogma that a ketogenic diet is unambiguously beneficial in mitochondrial disorders.
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Affiliation(s)
- Knut H Lauritzen
- Synaptic Neurochemistry Laboratory, Division of Anatomy and CMBN/SERTA Healthy Brain Ageing Centre, Institute of Basic Medical Sciences, University of Oslo, Oslo, Norway; Brain and Muscle Energy Group, Electron Microscopy Laboratory, Institute of Oral Biology, University of Oslo, Oslo, Norway
| | - Md Mahdi Hasan-Olive
- Synaptic Neurochemistry Laboratory, Division of Anatomy and CMBN/SERTA Healthy Brain Ageing Centre, Institute of Basic Medical Sciences, University of Oslo, Oslo, Norway; Brain and Muscle Energy Group, Electron Microscopy Laboratory, Institute of Oral Biology, University of Oslo, Oslo, Norway
| | - Christine E Regnell
- Synaptic Neurochemistry Laboratory, Division of Anatomy and CMBN/SERTA Healthy Brain Ageing Centre, Institute of Basic Medical Sciences, University of Oslo, Oslo, Norway; Brain and Muscle Energy Group, Electron Microscopy Laboratory, Institute of Oral Biology, University of Oslo, Oslo, Norway; Center for Healthy Aging and Department of Neuroscience and Pharmacology, Faculty of Health Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Liv Kleppa
- Synaptic Neurochemistry Laboratory, Division of Anatomy and CMBN/SERTA Healthy Brain Ageing Centre, Institute of Basic Medical Sciences, University of Oslo, Oslo, Norway; Brain and Muscle Energy Group, Electron Microscopy Laboratory, Institute of Oral Biology, University of Oslo, Oslo, Norway
| | - Morten Scheibye-Knudsen
- Laboratory of Molecular Gerontology, National Institute on Aging, National Institutes of Health, Baltimore, MD, USA
| | - Albert Gjedde
- Center for Healthy Aging and Department of Neuroscience and Pharmacology, Faculty of Health Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Arne Klungland
- Institute of Medical Microbiology, Oslo University Hospital and University of Oslo, Oslo, Norway; Department of Molecular Medicine, Institute of Basic Medical Sciences, University of Oslo, Oslo, Norway
| | - Vilhelm A Bohr
- Laboratory of Molecular Gerontology, National Institute on Aging, National Institutes of Health, Baltimore, MD, USA
| | - Jon Storm-Mathisen
- Synaptic Neurochemistry Laboratory, Division of Anatomy and CMBN/SERTA Healthy Brain Ageing Centre, Institute of Basic Medical Sciences, University of Oslo, Oslo, Norway
| | - Linda H Bergersen
- Synaptic Neurochemistry Laboratory, Division of Anatomy and CMBN/SERTA Healthy Brain Ageing Centre, Institute of Basic Medical Sciences, University of Oslo, Oslo, Norway; Brain and Muscle Energy Group, Electron Microscopy Laboratory, Institute of Oral Biology, University of Oslo, Oslo, Norway; Center for Healthy Aging and Department of Neuroscience and Pharmacology, Faculty of Health Sciences, University of Copenhagen, Copenhagen, Denmark.
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17
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Kolko M, Vosborg F, Henriksen UL, Hasan-Olive MM, Diget EH, Vohra R, Gurubaran IRS, Gjedde A, Mariga ST, Skytt DM, Utheim TP, Storm-Mathisen J, Bergersen LH. Erratum to: Lactate Transport and Receptor Actions in Retina: Potential Roles in Retinal Function and Disease. Neurochem Res 2016; 41:1237. [PMID: 27113043 DOI: 10.1007/s11064-016-1916-y] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Miriam Kolko
- Department of Neuroscience and Pharmacology, Faculty of Health Sciences, and Center for Healthy Aging, University of Copenhagen, The Panum Institute, Blegdamsvej 3B, 2200, Copenhagen, Denmark. .,Department of Ophthalmology, Roskilde Hospital, Roskilde, Denmark.
| | - Fia Vosborg
- Department of Neuroscience and Pharmacology, Faculty of Health Sciences, and Center for Healthy Aging, University of Copenhagen, The Panum Institute, Blegdamsvej 3B, 2200, Copenhagen, Denmark
| | - Ulrik L Henriksen
- Department of Neuroscience and Pharmacology, Faculty of Health Sciences, and Center for Healthy Aging, University of Copenhagen, The Panum Institute, Blegdamsvej 3B, 2200, Copenhagen, Denmark
| | - Md Mahdi Hasan-Olive
- Synaptic Neurochemistry Laboratory, Division of Anatomy, Institute of Basic Medical Sciences, University of Oslo, Oslo, Norway.,Brain and Muscle Energy Group, Faculty of Dentistry, Institute of Oral Biology, University of Oslo, PO Box 1152, Blindern, 0316, Oslo, Norway
| | - Elisabeth Holm Diget
- Department of Neuroscience and Pharmacology, Faculty of Health Sciences, and Center for Healthy Aging, University of Copenhagen, The Panum Institute, Blegdamsvej 3B, 2200, Copenhagen, Denmark.,Brain and Muscle Energy Group, Faculty of Dentistry, Institute of Oral Biology, University of Oslo, PO Box 1152, Blindern, 0316, Oslo, Norway
| | - Rupali Vohra
- Department of Neuroscience and Pharmacology, Faculty of Health Sciences, and Center for Healthy Aging, University of Copenhagen, The Panum Institute, Blegdamsvej 3B, 2200, Copenhagen, Denmark
| | - Iswariya Raja Sridevi Gurubaran
- Department of Neuroscience and Pharmacology, Faculty of Health Sciences, and Center for Healthy Aging, University of Copenhagen, The Panum Institute, Blegdamsvej 3B, 2200, Copenhagen, Denmark
| | - Albert Gjedde
- Department of Neuroscience and Pharmacology, Faculty of Health Sciences, and Center for Healthy Aging, University of Copenhagen, The Panum Institute, Blegdamsvej 3B, 2200, Copenhagen, Denmark
| | - Shelton Tendai Mariga
- Department of Neuroscience and Pharmacology, Faculty of Health Sciences, and Center for Healthy Aging, University of Copenhagen, The Panum Institute, Blegdamsvej 3B, 2200, Copenhagen, Denmark.,Synaptic Neurochemistry Laboratory, Division of Anatomy, Institute of Basic Medical Sciences, University of Oslo, Oslo, Norway.,Brain and Muscle Energy Group, Faculty of Dentistry, Institute of Oral Biology, University of Oslo, PO Box 1152, Blindern, 0316, Oslo, Norway
| | - Dorte M Skytt
- Department of Neuroscience and Pharmacology, Faculty of Health Sciences, and Center for Healthy Aging, University of Copenhagen, The Panum Institute, Blegdamsvej 3B, 2200, Copenhagen, Denmark
| | - Tor Paaske Utheim
- Brain and Muscle Energy Group, Faculty of Dentistry, Institute of Oral Biology, University of Oslo, PO Box 1152, Blindern, 0316, Oslo, Norway.,Department of Medical Biochemistry, Oslo University Hospital, Oslo, Norway
| | - Jon Storm-Mathisen
- Synaptic Neurochemistry Laboratory, Division of Anatomy, Institute of Basic Medical Sciences, University of Oslo, Oslo, Norway
| | - Linda H Bergersen
- Department of Neuroscience and Pharmacology, Faculty of Health Sciences, and Center for Healthy Aging, University of Copenhagen, The Panum Institute, Blegdamsvej 3B, 2200, Copenhagen, Denmark. .,Brain and Muscle Energy Group, Faculty of Dentistry, Institute of Oral Biology, University of Oslo, PO Box 1152, Blindern, 0316, Oslo, Norway.
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18
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Holm-Hansen S, Low JK, Zieba J, Gjedde A, Bergersen LH, Karl T. Behavioural effects of high fat diet in a mutant mouse model for the schizophrenia risk gene neuregulin 1. Genes Brain Behav 2016; 15:295-304. [PMID: 26707035 DOI: 10.1111/gbb.12267] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/25/2015] [Revised: 07/29/2015] [Accepted: 07/29/2015] [Indexed: 11/29/2022]
Abstract
Schizophrenia patients are often obese or overweight and poor dietary choices appear to be a factor in this phenomenon. Poor diet has been found to have complex consequences for the mental state of patients. Thus, this study investigated whether an unhealthy diet [i.e. high fat diet (HFD)] impacts on the behaviour of a genetic mouse model for the schizophrenia risk gene neuregulin 1 (i.e. transmembrane domain Nrg1 mutant mice: Nrg1 HET). Female Nrg1 HET and wild-type-like littermates (WT) were fed with either HFD or a control chow diet. The mice were tested for baseline (e.g. anxiety) and schizophrenia-relevant behaviours after 7 weeks of diet exposure. HFD increased body weight and impaired glucose tolerance in all mice. Only Nrg1 females on HFD displayed a hyper-locomotive phenotype as locomotion-suppressive effects of HFD were only evident in WT mice. HFD also induced an anxiety-like response and increased freezing in the context and the cued version of the fear conditioning task. Importantly, CHOW-fed Nrg1 females displayed impaired social recognition memory, which was absent in HFD-fed mutants. Sensorimotor gating deficits of Nrg1 females were not affected by diet. In summary, HFD had complex effects on the behavioural phenotype of test mice and attenuated particular cognitive deficits of Nrg1 mutant females. This topic requires further investigations thereby also considering other dietary factors of relevance for schizophrenia as well as interactive effects of diet with medication and sex.
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Affiliation(s)
- S Holm-Hansen
- Department of Neuroscience and Pharmacology, University of Copenhagen, Copenhagen, Denmark.,Brain and Muscle Energy Group, Electron Microscopy Laboratory, Institute of Oral Biology, University of Oslo, Oslo, Norway
| | - J K Low
- Neuroscience Research Australia, Sydney, Australia.,Schizophrenia Research Institute, Randwick, Australia
| | - J Zieba
- Neuroscience Research Australia, Sydney, Australia.,Schizophrenia Research Institute, Randwick, Australia
| | - A Gjedde
- Department of Neuroscience and Pharmacology, University of Copenhagen, Copenhagen, Denmark.,Center for Healthy Aging, Faculty of Health Sciences, University of Copenhagen, Copenhagen, Denmark
| | - L H Bergersen
- Department of Neuroscience and Pharmacology, University of Copenhagen, Copenhagen, Denmark.,Brain and Muscle Energy Group, Electron Microscopy Laboratory, Institute of Oral Biology, University of Oslo, Oslo, Norway.,Center for Healthy Aging, Faculty of Health Sciences, University of Copenhagen, Copenhagen, Denmark
| | - T Karl
- Neuroscience Research Australia, Sydney, Australia.,Schizophrenia Research Institute, Randwick, Australia.,School of Medical Sciences, University of New South Wales, Sydney, Australia
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19
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Rinholm JE, Vervaeke K, Tadross MR, Tkachuk AN, Kopek BG, Brown TA, Bergersen LH, Clayton DA. Movement and structure of mitochondria in oligodendrocytes and their myelin sheaths. Glia 2016; 64:810-25. [PMID: 26775288 DOI: 10.1002/glia.22965] [Citation(s) in RCA: 74] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2015] [Accepted: 12/22/2015] [Indexed: 12/30/2022]
Abstract
Mitochondria play several crucial roles in the life of oligodendrocytes. During development of the myelin sheath they are essential providers of carbon skeletons and energy for lipid synthesis. During normal brain function their consumption of pyruvate will be a key determinant of how much lactate is available for oligodendrocytes to export to power axonal function. Finally, during calcium-overload induced pathology, as occurs in ischemia, mitochondria may buffer calcium or induce apoptosis. Despite their important functions, very little is known of the properties of oligodendrocyte mitochondria, and mitochondria have never been observed in the myelin sheaths. We have now used targeted expression of fluorescent mitochondrial markers to characterize the location and movement of mitochondria within oligodendrocytes. We show for the first time that mitochondria are able to enter and move within the myelin sheath. Within the myelin sheath the highest number of mitochondria was in the cytoplasmic ridges along the sheath. Mitochondria moved more slowly than in neurons and, in contrast to their behavior in neurons and astrocytes, their movement was increased rather than inhibited by glutamate activating NMDA receptors. By electron microscopy we show that myelin sheath mitochondria have a low surface area of cristae, which suggests a low ATP production. These data specify fundamental properties of the oxidative phosphorylation system in oligodendrocytes, the glial cells that enhance cognition by speeding action potential propagation and provide metabolic support to axons.
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Affiliation(s)
- Johanne E Rinholm
- Department of Anatomy, The Brain and Muscle Energy Group, University of Oslo, Oslo, Norway.,Department of Oral Biology, The Brain and Muscle Energy Group, Electron Microscopic Laboratory, University of Oslo, Oslo, Norway.,Howard Hughes Medical Institute, Ashburn, Virginia
| | - Koen Vervaeke
- Howard Hughes Medical Institute, Ashburn, Virginia.,Department of Physiology, Laboratory of Neural Computation, University of Oslo, Oslo, Norway
| | | | | | | | | | - Linda H Bergersen
- Department of Oral Biology, The Brain and Muscle Energy Group, Electron Microscopic Laboratory, University of Oslo, Oslo, Norway
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20
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Lauritzen KH, Kleppa L, Aronsen JM, Eide L, Carlsen H, Haugen ØP, Sjaastad I, Klungland A, Rasmussen LJ, Attramadal H, Storm-Mathisen J, Bergersen LH. Impaired dynamics and function of mitochondria caused by mtDNA toxicity leads to heart failure. Am J Physiol Heart Circ Physiol 2015; 309:H434-49. [PMID: 26055793 DOI: 10.1152/ajpheart.00253.2014] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/15/2014] [Accepted: 06/02/2015] [Indexed: 11/22/2022]
Abstract
Cardiac mitochondrial dysfunction has been implicated in heart failure of diverse etiologies. Generalized mitochondrial disease also leads to cardiomyopathy with various clinical manifestations. Impaired mitochondrial homeostasis may over time, such as in the aging heart, lead to cardiac dysfunction. Mitochondrial DNA (mtDNA), close to the electron transport chain and unprotected by histones, may be a primary pathogenetic site, but this is not known. Here, we test the hypothesis that cumulative damage of cardiomyocyte mtDNA leads to cardiomyopathy and heart failure. Transgenic mice with Tet-on inducible, cardiomyocyte-specific expression of a mutant uracil-DNA glycosylase 1 (mutUNG1) were generated. The mutUNG1 is known to remove thymine in addition to uracil from the mitochondrial genome, generating apyrimidinic sites, which obstruct mtDNA function. Following induction of mutUNG1 in cardiac myocytes by administering doxycycline, the mice developed hypertrophic cardiomyopathy, leading to congestive heart failure and premature death after ∼2 mo. The heart showed reduced mtDNA replication, severely diminished mtDNA transcription, and suppressed mitochondrial respiration with increased Pgc-1α, mitochondrial mass, and antioxidative defense enzymes, and finally failing mitochondrial fission/fusion dynamics and deteriorating myocardial contractility as the mechanism of heart failure. The approach provides a model with induced cardiac-restricted mtDNA damage for investigation of mtDNA-based heart disease.
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Affiliation(s)
- Knut H Lauritzen
- Department of Oral Biology, Brain and Muscle Energy Group, University of Oslo, Oslo, Norway; Department of Anatomy, Institute of Basic Medical Sciences, and Healthy Brain Ageing Centre, University of Oslo, Oslo, Norway
| | - Liv Kleppa
- Department of Oral Biology, Brain and Muscle Energy Group, University of Oslo, Oslo, Norway; Department of Anatomy, Institute of Basic Medical Sciences, and Healthy Brain Ageing Centre, University of Oslo, Oslo, Norway
| | - Jan Magnus Aronsen
- Institute for Experimental Medical Research, Oslo University Hospital Ullevål and University of Oslo, Oslo, Norway; KG Jebsen Cardiac Research Center and Center for Heart Failure Research, University of Oslo, Norway, Oslo, Norway
| | - Lars Eide
- Department of Medical Biochemistry, University of Oslo, Oslo, Norway
| | - Harald Carlsen
- Department of Nutrition Research, Institute of Basic Medical Sciences, University of Oslo, Oslo, Norway
| | - Øyvind P Haugen
- Department of Oral Biology, Brain and Muscle Energy Group, University of Oslo, Oslo, Norway; Department of Anatomy, Institute of Basic Medical Sciences, and Healthy Brain Ageing Centre, University of Oslo, Oslo, Norway
| | - Ivar Sjaastad
- Institute for Experimental Medical Research, Oslo University Hospital Ullevål and University of Oslo, Oslo, Norway; KG Jebsen Cardiac Research Center and Center for Heart Failure Research, University of Oslo, Norway, Oslo, Norway
| | - Arne Klungland
- Department of Nutrition Research, Institute of Basic Medical Sciences, University of Oslo, Oslo, Norway; Institute of Medical Microbiology, Oslo University Hospital, Oslo, Norway
| | - Lene Juel Rasmussen
- Center for Healthy Aging, University of Copenhagen, Copenhagen, Denmark; Department of Cellular and Molecular Medicine, University of Copenhagen, Denmark
| | - Håvard Attramadal
- Institute for Surgical Research, Oslo University Hospital, Oslo, Norway; and Center for Heart Failure Research, University of Oslo, Oslo, Norway
| | - Jon Storm-Mathisen
- Department of Anatomy, Institute of Basic Medical Sciences, and Healthy Brain Ageing Centre, University of Oslo, Oslo, Norway
| | - Linda H Bergersen
- Department of Oral Biology, Brain and Muscle Energy Group, University of Oslo, Oslo, Norway; Center for Healthy Aging, University of Copenhagen, Copenhagen, Denmark;
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21
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Affiliation(s)
- Linda H Bergersen
- From the Departments of Oral Biology and of Basic Medical Sciences, University of Oslo, Oslo (L.H.B.); and the Department of Laboratory Medicine, Yale University School of Medicine, New Haven, CT (T.E.)
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22
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Scheibye-Knudsen M, Mitchell SJ, Fang EF, Iyama T, Ward T, Wang J, Dunn CA, Singh N, Veith S, Hasan-Olive MM, Mangerich A, Wilson MA, Mattson MP, Bergersen LH, Cogger VC, Warren A, Le Couteur DG, Moaddel R, Wilson DM, Croteau DL, de Cabo R, Bohr VA. A high-fat diet and NAD(+) activate Sirt1 to rescue premature aging in cockayne syndrome. Cell Metab 2014; 20:840-855. [PMID: 25440059 PMCID: PMC4261735 DOI: 10.1016/j.cmet.2014.10.005] [Citation(s) in RCA: 262] [Impact Index Per Article: 26.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/15/2014] [Revised: 07/12/2014] [Accepted: 10/06/2014] [Indexed: 12/15/2022]
Abstract
Cockayne syndrome (CS) is an accelerated aging disorder characterized by progressive neurodegeneration caused by mutations in genes encoding the DNA repair proteins CS group A or B (CSA or CSB). Since dietary interventions can alter neurodegenerative processes, Csb(m/m) mice were given a high-fat, caloric-restricted, or resveratrol-supplemented diet. High-fat feeding rescued the metabolic, transcriptomic, and behavioral phenotypes of Csb(m/m) mice. Furthermore, premature aging in CS mice, nematodes, and human cells results from aberrant PARP activation due to deficient DNA repair leading to decreased SIRT1 activity and mitochondrial dysfunction. Notably, β-hydroxybutyrate levels are increased by the high-fat diet, and β-hydroxybutyrate, PARP inhibition, or NAD(+) supplementation can activate SIRT1 and rescue CS-associated phenotypes. Mechanistically, CSB can displace activated PARP1 from damaged DNA to limit its activity. This study connects two emerging longevity metabolites, β-hydroxybutyrate and NAD(+), through the deacetylase SIRT1 and suggests possible interventions for CS.
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Affiliation(s)
- Morten Scheibye-Knudsen
- Laboratory of Molecular Gerontology, National Institute on Aging, National Institutes of Health, Baltimore, MD 21224, USA
| | - Sarah J Mitchell
- Translational Gerontology Branch, National Institute on Aging, National Institutes of Health, Baltimore, MD 21224, USA; Sydney Medical School, University of Sydney, Sydney, NSW 2006, Australia
| | - Evandro F Fang
- Laboratory of Molecular Gerontology, National Institute on Aging, National Institutes of Health, Baltimore, MD 21224, USA
| | - Teruaki Iyama
- Laboratory of Molecular Gerontology, National Institute on Aging, National Institutes of Health, Baltimore, MD 21224, USA
| | - Theresa Ward
- Translational Gerontology Branch, National Institute on Aging, National Institutes of Health, Baltimore, MD 21224, USA
| | - James Wang
- Laboratory of Molecular Gerontology, National Institute on Aging, National Institutes of Health, Baltimore, MD 21224, USA
| | - Christopher A Dunn
- Laboratory of Molecular Gerontology, National Institute on Aging, National Institutes of Health, Baltimore, MD 21224, USA
| | - Nagendra Singh
- Laboratory of Clinical Investigation, National Institute on Aging, National Institutes of Health, Baltimore, MD 21224, USA
| | - Sebastian Veith
- Molecular Toxicology Group, Department of Biology, University of Konstanz, D-78457 Konstanz, Germany
| | - Md Mahdi Hasan-Olive
- Laboratory of Neurosciences, National Institute on Aging, National Institutes of Health, Baltimore, MD 21224, USA
| | - Aswin Mangerich
- Molecular Toxicology Group, Department of Biology, University of Konstanz, D-78457 Konstanz, Germany
| | - Mark A Wilson
- Laboratory of Neurosciences, National Institute on Aging, National Institutes of Health, Baltimore, MD 21224, USA
| | - Mark P Mattson
- Laboratory of Neurosciences, National Institute on Aging, National Institutes of Health, Baltimore, MD 21224, USA
| | - Linda H Bergersen
- The Brain and Muscle Energy Group - Synaptic Neurochemistry Laboratory, Department of Anatomy, Institute of Basic Medical Sciences, University of Oslo, 0317 Oslo, Norway; Danish Center for Healthy Aging, ICMM, University of Copenhagen, Copenhagen, Denmark
| | - Victoria C Cogger
- Sydney Medical School, University of Sydney, Sydney, NSW 2006, Australia; Centre for Education and Research on Ageing and ANZAC Research Institute, Concord Hospital and University of Sydney, Sydney, NSW 2139, Australia
| | - Alessandra Warren
- Centre for Education and Research on Ageing and ANZAC Research Institute, Concord Hospital and University of Sydney, Sydney, NSW 2139, Australia
| | - David G Le Couteur
- Sydney Medical School, University of Sydney, Sydney, NSW 2006, Australia; Centre for Education and Research on Ageing and ANZAC Research Institute, Concord Hospital and University of Sydney, Sydney, NSW 2139, Australia
| | - Ruin Moaddel
- Laboratory of Clinical Investigation, National Institute on Aging, National Institutes of Health, Baltimore, MD 21224, USA
| | - David M Wilson
- Laboratory of Molecular Gerontology, National Institute on Aging, National Institutes of Health, Baltimore, MD 21224, USA
| | - Deborah L Croteau
- Laboratory of Molecular Gerontology, National Institute on Aging, National Institutes of Health, Baltimore, MD 21224, USA
| | - Rafael de Cabo
- Translational Gerontology Branch, National Institute on Aging, National Institutes of Health, Baltimore, MD 21224, USA.
| | - Vilhelm A Bohr
- Laboratory of Molecular Gerontology, National Institute on Aging, National Institutes of Health, Baltimore, MD 21224, USA; Danish Center for Healthy Aging, ICMM, University of Copenhagen, Copenhagen, Denmark.
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23
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Abstract
Cerebral malaria (CM), caused by Plasmodium falciparum infection, is a prevalent neurological disorder in the tropics. Most of the patients are children, typically with intractable seizures and high mortality. Current treatment is unsatisfactory. Understanding the pathogenesis of CM is required in order to identify therapeutic targets. Here, we argue that cerebral energy metabolic defects are probable etiological factors in CM pathogenesis, because malaria parasites consume large amounts of glucose metabolized mostly to lactate. Monocarboxylate transporters (MCTs) mediate facilitated transfer, which serves to equalize lactate concentrations across cell membranes in the direction of the concentration gradient. The equalizing action of MCTs is the basis for lactate’s role as a volume transmitter of metabolic signals in the brain. Lactate binds to the lactate receptor GPR81, recently discovered on brain cells and cerebral blood vessels, causing inhibition of adenylyl cyclase. High levels of lactate delivered by the parasite at the vascular endothelium may damage the blood–brain barrier, disrupt lactate homeostasis in the brain, and imply MCTs and the lactate receptor as novel therapeutic targets in CM.
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Affiliation(s)
- Shelton T Mariga
- Department of Neuroscience and Pharmacology, University of Copenhagen Copenhagen, Denmark
| | - Miriam Kolko
- Department of Neuroscience and Pharmacology, University of Copenhagen Copenhagen, Denmark ; Department of Ophthalmology, Roskilde Hospital Roskilde, Denmark
| | - Albert Gjedde
- Department of Neuroscience and Pharmacology, University of Copenhagen Copenhagen, Denmark
| | - Linda H Bergersen
- Department of Neuroscience and Pharmacology, University of Copenhagen Copenhagen, Denmark ; The Brain and Muscle Energy Group and SN-Lab, Department of Anatomy and Department of Oral Biology, Institute of Basic Medical Sciences and Centre for Molecular Biology and Neuroscience/SERTA Healthy Brain Aging Centre, University of Oslo Oslo, Norway
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24
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Lauritzen F, Eid T, Bergersen LH. Monocarboxylate transporters in temporal lobe epilepsy: roles of lactate and ketogenic diet. Brain Struct Funct 2013; 220:1-12. [PMID: 24248427 DOI: 10.1007/s00429-013-0672-x] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2013] [Accepted: 11/05/2013] [Indexed: 11/29/2022]
Abstract
Epilepsy is a serious neurological disorder that affects approximately 1 % of the general population, making it one of the most common disorders of the central nervous system. Furthermore, up to 40 % of all patients with epilepsy cannot control their seizures with current medications. More efficacious treatments for medication refractory epilepsy are therefore needed. A better understanding of the mechanisms that cause this disorder is likely to facilitate the discovery of such treatments. Impairment in cerebral energy metabolism has been proposed as a possible causative factor in the pathogenesis of temporal lobe epilepsy (TLE), which is one of the most common types of medication-refractory epilepsies in adults. In this review, we will discuss some of the current hypotheses regarding the possible causal relationship between brain energy metabolism and TLE. Emphasis will be placed on the role of energy substrates (lactate and ketone bodies) and their transporter molecules, particularly monocarboxylate transporters 1 and 2 (MCT1 and MCT2). We recently reported that the cellular distribution of MCT1 and MCT2 is perturbed in the hippocampus in patients with TLE. The changes may be an adaptive response aimed at keeping high levels of lactate in the epileptic tissue, which may serve to counteract epileptic activity by downregulating cAMP levels through the lactate receptor GPR81, newly discovered in hippocampus. We propose that the perturbation of MCTs may be further involved in the pathophysiology of TLE by influencing brain energy homeostasis, mitochondrial function, GABA-ergic and glutamatergic neurotransmission, and flux of lactate through the brain.
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Affiliation(s)
- Fredrik Lauritzen
- The Brain and Muscle Energy Group, Department of Anatomy and Department of Oral Biology, University of Oslo, P.O. Box 1105, Blindern, 0317, Oslo, Norway
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25
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Nagelhus EA, Amiry-Moghaddam M, Bergersen LH, Bjaalie JG, Eriksson J, Gundersen V, Leergaard TB, Morth JP, Storm-Mathisen J, Torp R, Walhovd KB, Tønjum T. The glia doctrine: addressing the role of glial cells in healthy brain ageing. Mech Ageing Dev 2013; 134:449-59. [PMID: 24141107 DOI: 10.1016/j.mad.2013.10.001] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2013] [Revised: 10/03/2013] [Accepted: 10/04/2013] [Indexed: 01/14/2023]
Abstract
Glial cells in their plurality pervade the human brain and impact on brain structure and function. A principal component of the emerging glial doctrine is the hypothesis that astrocytes, the most abundant type of glial cells, trigger major molecular processes leading to brain ageing. Astrocyte biology has been examined using molecular, biochemical and structural methods, as well as 3D brain imaging in live animals and humans. Exosomes are extracelluar membrane vesicles that facilitate communication between glia, and have significant potential for biomarker discovery and drug delivery. Polymorphisms in DNA repair genes may indirectly influence the structure and function of membrane proteins expressed in glial cells and predispose specific cell subgroups to degeneration. Physical exercise may reduce or retard age-related brain deterioration by a mechanism involving neuro-glial processes. It is most likely that additional information about the distribution, structure and function of glial cells will yield novel insight into human brain ageing. Systematic studies of glia and their functions are expected to eventually lead to earlier detection of ageing-related brain dysfunction and to interventions that could delay, reduce or prevent brain dysfunction.
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Affiliation(s)
- Erlend A Nagelhus
- Department of Physiology, Institute of Basic Medical Sciences, University of Oslo, Norway; Centre for Molecular Medicine Norway (NCMM), The Nordic EMBL Partnership, University of Oslo, Norway; Department of Neurology, Oslo University Hospital, Norway
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26
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Abstract
About half of the human brain is white matter, characterized by axons covered in myelin, which facilitates the high speed of nerve signals from one brain area to another. At the time of myelination, the oligodendrocytes that synthesize myelin require a large amount of energy for this task. Conditions that deprive the tissue of energy can kill the oligodendrocytes. During brain development, the oligodendrocytes may use lactate as an alternative source of energy and material for myelin formation. Mature oligodendrocytes, however, can release lactate through the myelin sheath as nutrient for axons. In addition, lactate carries signals as a volume transmitter. Myelin thus seems to serve as a provider of substrates and signals for axons, and not as a mere insulator. We review the fluxes of lactate in white matter and their significance in brain function.
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Affiliation(s)
- J E Rinholm
- The Brain and Muscle Energy Group, Department of Anatomy, Institute of Basic Medical Sciences, University of Oslo, PB1105 Blindern, N-0317 Oslo, Norway; Janelia Farm Research Campus, Howard Hughes Medical Institute, Ashburn, VA, USA
| | - L H Bergersen
- The Brain and Muscle Energy Group, Department of Anatomy, Institute of Basic Medical Sciences, University of Oslo, PB1105 Blindern, N-0317 Oslo, Norway; Department of Neuroscience and Pharmacology, University of Copenhagen, Copenhagen, Denmark; Center for Healthy Aging, Faculty of Health Sciences, University of Copenhagen, Copenhagen, Denmark; Department of Oral Biology, University of Oslo, Norway.
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27
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Rodell A, Rasmussen LJ, Bergersen LH, Singh KK, Gjedde A. Natural selection of mitochondria during somatic lifetime promotes healthy aging. Front Neuroenergetics 2013; 5:7. [PMID: 23964235 PMCID: PMC3740293 DOI: 10.3389/fnene.2013.00007] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/22/2013] [Accepted: 07/22/2013] [Indexed: 01/08/2023]
Abstract
Stimulation of mitochondrial biogenesis during life-time challenges both eliminates disadvantageous properties and drives adaptive selection of advantageous phenotypic variations. Intermittent fission and fusion of mitochondria provide specific targets for health promotion by brief temporal stressors, interspersed with periods of recovery and biogenesis. For mitochondria, the mechanisms of selection, variability, and heritability, are complicated by interaction of two independent genomes, including the multiple copies of DNA in each mitochondrion, as well as the shared nuclear genome of each cell. The mechanisms of stress-induced fission, followed by recovery-induced fusion and biogenesis, drive the improvement of mitochondrial functions, not only as directed by genotypic variations, but also as enabled by phenotypic diversity. Selective adaptation may explain unresolved aspects of aging, including the health effects of exercise, hypoxic and poisonous preconditioning, and tissue-specific mitochondrial differences. We propose that intermittent purposeful enhancement of mitochondrial biogenesis by stressful episodes with subsequent recovery paradoxically promotes adaptive mitochondrial health and continued healthy aging.
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Affiliation(s)
- Anders Rodell
- Department of Nuclear Medicine & PET Centre, Aarhus University Hospital Aarhus, Denmark
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Lauritzen KH, Morland C, Puchades M, Holm-Hansen S, Hagelin EM, Lauritzen F, Attramadal H, Storm-Mathisen J, Gjedde A, Bergersen LH. Lactate receptor sites link neurotransmission, neurovascular coupling, and brain energy metabolism. Cereb Cortex 2013; 24:2784-95. [PMID: 23696276 DOI: 10.1093/cercor/bht136] [Citation(s) in RCA: 228] [Impact Index Per Article: 20.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
The G-protein-coupled lactate receptor, GPR81 (HCA1), is known to promote lipid storage in adipocytes by downregulating cAMP levels. Here, we show that GPR81 is also present in the mammalian brain, including regions of the cerebral neocortex and hippocampus, where it can be activated by physiological concentrations of lactate and by the specific GPR81 agonist 3,5-dihydroxybenzoate to reduce cAMP. Cerebral GPR81 is concentrated on the synaptic membranes of excitatory synapses, with a postsynaptic predominance. GPR81 is also enriched at the blood-brain-barrier: the GPR81 densities at endothelial cell membranes are about twice the GPR81 density at membranes of perivascular astrocytic processes, but about one-seventh of that on synaptic membranes. There is only a slight signal in perisynaptic processes of astrocytes. In synaptic spines, as well as in adipocytes, GPR81 immunoreactivity is located on subplasmalemmal vesicular organelles, suggesting trafficking of the protein to and from the plasma membrane. The results indicate roles of lactate in brain signaling, including a neuronal glucose and glycogen saving response to the supply of lactate. We propose that lactate, through activation of GPR81 receptors, can act as a volume transmitter that links neuronal activity, cerebral energy metabolism and energy substrate availability.
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Affiliation(s)
- Knut H Lauritzen
- The Brain and Muscle Energy Group, Department of Neuroscience and Pharmacology, Center for Healthy Aging, Faculty of Health Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Cecilie Morland
- The Brain and Muscle Energy Group, Glio- and Neurotransmitter Group, Synaptic Neurochemistry Lab, Department of Anatomy and Centre for Molecular Biology and Neuroscience/SERTA Healthy Brain Aging, Institute of Basic Medical Sciences, University of Oslo, Oslo, Norway
| | - Maja Puchades
- Glio- and Neurotransmitter Group, Synaptic Neurochemistry Lab, Department of Anatomy and Centre for Molecular Biology and Neuroscience/SERTA Healthy Brain Aging, Institute of Basic Medical Sciences, University of Oslo, Oslo, Norway
| | - Signe Holm-Hansen
- The Brain and Muscle Energy Group, Department of Neuroscience and Pharmacology, Center for Healthy Aging, Faculty of Health Sciences, University of Copenhagen, Copenhagen, Denmark
| | | | - Fredrik Lauritzen
- The Brain and Muscle Energy Group, Department of Neuroscience and Pharmacology, Center for Healthy Aging, Faculty of Health Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Håvard Attramadal
- Institute for Surgical Research, Oslo University Hospital, Oslo, Norway, Center for Heart Failure Research
| | - Jon Storm-Mathisen
- The Brain and Muscle Energy Group, Glio- and Neurotransmitter Group, Synaptic Neurochemistry Lab, Department of Anatomy and Centre for Molecular Biology and Neuroscience/SERTA Healthy Brain Aging, Institute of Basic Medical Sciences, University of Oslo, Oslo, Norway
| | - Albert Gjedde
- Department of Neuroscience and Pharmacology, Center for Healthy Aging, Faculty of Health Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Linda H Bergersen
- The Brain and Muscle Energy Group, Department of Neuroscience and Pharmacology, Center for Healthy Aging, Faculty of Health Sciences, University of Copenhagen, Copenhagen, Denmark, Institute of Oral Biology, University of Oslo, Norway
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Rasmussen LJ, Shiloh Y, Bergersen LH, Sander M, Bohr VA, Tønjum T. DNA damage response, bioenergetics, and neurological disease: the challenge of maintaining brain health in an aging human population. Mech Ageing Dev 2013; 134:427-33. [PMID: 23665461 PMCID: PMC5903438 DOI: 10.1016/j.mad.2013.05.001] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Affiliation(s)
- Lene Juel Rasmussen
- Center for Healthy Aging, Faculty of Health Sciences, University of Copenhagen, Denmark
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Eid T, Lee TSW, Wang Y, Perez E, Peréz E, Drummond J, Lauritzen F, Bergersen LH, Meador-Woodruff JH, Spencer DD, de Lanerolle NC, McCullumsmith RE. Gene expression of glutamate metabolizing enzymes in the hippocampal formation in human temporal lobe epilepsy. Epilepsia 2013; 54:228-38. [PMID: 23384343 PMCID: PMC3578420 DOI: 10.1111/epi.12008] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
PURPOSE Increased interictal concentrations of extracellular hippocampal glutamate have been implicated in the pathophysiology of temporal lobe epilepsy (TLE). Recent studies suggest that perturbations of the glutamate metabolizing enzymes glutamine synthetase (GS) and phosphate activated glutaminase (PAG) may underlie the glutamate excess in TLE. However, the molecular mechanism of the enzyme perturbations remains unclear. A better understanding of the regulatory mechanisms of GS and PAG could facilitate the discovery of novel therapeutics for TLE. METHODS We used in situ hybridization on histologic sections to assess the distribution and quantity of messenger RNA (mRNA) for GS and PAG in subfields of hippocampal formations from the following: (1) patients with TLE and concomitant hippocampal sclerosis, (2) patients with TLE and no hippocampal sclerosis, and (3) nonepilepsy autopsy subjects. KEY FINDINGS GS mRNA was increased by ~50% in the CA3 in TLE patients without hippocampal sclerosis versus in TLE patients with sclerosis and in nonepilepsy subjects. PAG mRNA was increased by >100% in the subiculum in both TLE patient categories versus in nonepilepsy subjects. PAG mRNA was also increased in the CA1, CA2, CA3, and dentate hilus in TLE without hippocampal sclerosis versus in TLE with sclerosis. Finally, PAG mRNA was increased in the dentate gyrus in TLE with sclerosis versus in nonepilepsy subjects, and also increased in the hilus in TLE without sclerosis versus in TLE with sclerosis. SIGNIFICANCE These findings demonstrate complex changes in the expression of mRNAs for GS and PAG in the hippocampal formation in TLE, and raise the possibility that both transcriptional and posttranscriptional mechanisms may underlie the regulation of GS and PAG proteins in the epileptic brain.
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Affiliation(s)
- Tore Eid
- Departments of Laboratory Medicine Psychiatry Neurosurgery, Yale University School of Medicine, New Haven, Connecticut 06520-8035, USA.
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Puchades M, Sogn CJ, Maehlen J, Bergersen LH, Gundersen V. Unaltered lactate and glucose transporter levels in the MPTP mouse model of Parkinson's disease. Journal of Parkinson's Disease 2013; 3:371-85. [DOI: 10.3233/jpd-130190] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Affiliation(s)
- Maja Puchades
- Glio- and Neurotransmitter Group, Centre for Molecular Biology and Neuroscience and Institute for Basic Medical Sciences, University of Oslo, Oslo, Norway
| | - Carl Johan Sogn
- Glio- and Neurotransmitter Group, Centre for Molecular Biology and Neuroscience and Institute for Basic Medical Sciences, University of Oslo, Oslo, Norway
| | - Jan Maehlen
- Department of Pathology, Oslo University Hospital-Ullevål. Oslo, Norway
| | - Linda H. Bergersen
- The Brain and Muscle Energy Group, Centre for Molecular Biology and Neuroscience and Institute for Basic Medical Sciences, University of Oslo, Oslo, Norway
- Department of Neuroscience and Pharmacology, University of Copenhagen, Copenhagen, Denmark
- Center for Healthy Aging, Faculty of Health Sciences, University of Copenhagen, Copenhagen, Denmark
- Department of Neurology, Oslo University Hospital, Norway
| | - Vidar Gundersen
- Glio- and Neurotransmitter Group, Centre for Molecular Biology and Neuroscience and Institute for Basic Medical Sciences, University of Oslo, Oslo, Norway
- Department of Oral Biology, University of Oslo, Norway
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Regnell CE, Hildrestrand GA, Sejersted Y, Medin T, Moldestad O, Rolseth V, Krokeide SZ, Suganthan R, Luna L, Bjørås M, Bergersen LH. Hippocampal adult neurogenesis is maintained by Neil3-dependent repair of oxidative DNA lesions in neural progenitor cells. Cell Rep 2012; 2:503-10. [PMID: 22959434 DOI: 10.1016/j.celrep.2012.08.008] [Citation(s) in RCA: 76] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2012] [Revised: 06/14/2012] [Accepted: 08/10/2012] [Indexed: 12/31/2022] Open
Abstract
Accumulation of oxidative DNA damage has been proposed as a potential cause of age-related cognitive decline. The major pathway for removal of oxidative DNA base lesions is base excision repair, which is initiated by DNA glycosylases. In mice, Neil3 is the main DNA glycosylase for repair of hydantoin lesions in single-stranded DNA of neural stem/progenitor cells, promoting neurogenesis. Adult neurogenesis is crucial for maintenance of hippocampus-dependent functions involved in behavior. Herein, behavioral studies reveal learning and memory deficits and reduced anxiety-like behavior in Neil3(-/-) mice. Neural stem/progenitor cells from aged Neil3(-/-) mice show impaired proliferative capacity and reduced DNA repair activity. Furthermore, hippocampal neurons in Neil3(-/-) mice display synaptic irregularities. It appears that Neil3-dependent repair of oxidative DNA damage in neural stem/progenitor cells is required for maintenance of adult neurogenesis to counteract the age-associated deterioration of cognitive performance.
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Affiliation(s)
- Christine Elisabeth Regnell
- Department of Anatomy, Centre for Molecular Biology and Neuroscience, University of Oslo, N-0317 Oslo, Norway
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Perez EL, Lauritzen F, Wang Y, Lee TSW, Kang D, Zaveri HP, Chaudhry FA, Ottersen OP, Bergersen LH, Eid T. Evidence for astrocytes as a potential source of the glutamate excess in temporal lobe epilepsy. Neurobiol Dis 2012; 47:331-7. [PMID: 22659305 DOI: 10.1016/j.nbd.2012.05.010] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2011] [Revised: 05/07/2012] [Accepted: 05/24/2012] [Indexed: 12/26/2022] Open
Abstract
Increased extracellular brain glutamate has been implicated in the pathophysiology of human refractory temporal lobe epilepsy (TLE), but the cause of the excessive glutamate is unknown. Prior studies by us and others have shown that the glutamate degrading enzyme glutamine synthetase (GS) is deficient in astrocytes in the epileptogenic hippocampal formation in a subset of patients with TLE. We have postulated that the loss of GS in TLE leads to increased glutamate in astrocytes with elevated concentrations of extracellular glutamate and recurrent seizures as the ultimate end-points. Here we test the hypothesis that the deficiency in GS leads to increased glutamate in astrocytes. Rats were chronically infused with methionine sulfoximine (MSO, n=4) into the hippocampal formation to induce GS deficiency and recurrent seizures. A separate group of rats was infused with 0.9% NaCl (saline) as a control (n=6). At least 10days after the start of infusion, once recurrent seizures were established in the MSO-treated rats, the concentration of glutamate was assessed in CA1 of the hippocampal formation by immunogold electron microscopy. The concentration of glutamate was 47% higher in astrocytes in the MSO-treated vs. saline-treated rats (p=0.02), and the ratio of glutamate in astrocytes relative to axon terminals was increased by 74% in the MSO-treated rats (p=0.003). These data support our hypothesis that a deficiency in GS leads to increased glutamate in astrocytes. We additionally propose that the GS-deficient astrocytes in the hippocampal formation in TLE lead to elevated extracellular brain glutamate either through decreased clearance of extracellular glutamate or excessive release of glutamate into the extracellular space from these cells, or a combination of the two.
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Affiliation(s)
- Edgar L Perez
- Department of Laboratory Medicine, Yale University School of Medicine, New Haven, CT 06520, USA
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35
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Lauritzen F, Heuser K, de Lanerolle NC, Lee TSW, Spencer DD, Kim JH, Gjedde A, Eid T, Bergersen LH. Redistribution of monocarboxylate transporter 2 on the surface of astrocytes in the human epileptogenic hippocampus. Glia 2012; 60:1172-81. [PMID: 22535546 DOI: 10.1002/glia.22344] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2011] [Accepted: 03/30/2012] [Indexed: 01/05/2023]
Abstract
Emerging evidence points to monocarboxylates as key players in the pathophysiology of temporal lobe epilepsy (TLE) with hippocampal sclerosis (mesial temporal lobe epilepsy, MTLE). Monocarboxylate transporters (MCTs) 1 and 2, which are abundantly present on brain endothelial cells and perivascular astrocyte endfeet, respectively, facilitate the transport of monocarboxylates and protons across cell membranes. Recently, we reported that the density of MCT1 protein is reduced on endothelial cells and increased on astrocyte plasma membranes in the hippocampal formation in patients with MTLE and in several animal models of the disorder. Because the perivascular astrocyte endfeet comprise an important part of the neurovascular unit, we now assessed the distribution of the MCT2 in hippocampal formations in TLE patients with (MTLE) or without hippocampal sclerosis (non-MTLE). Light microscopic immunohistochemistry revealed significantly less perivascular MCT2 immunoreactivity in the hippocampal formation in MTLE (n = 6) than in non-MTLE (n = 6) patients, and to a lesser degree in non-MTLE than in nonepilepsy patients (n = 4). Immunogold electron microscopy indicated that the loss of MCT2 protein occurred on perivascular astrocyte endfeet. Interestingly, the loss of MCT2 on astrocyte endfeet in MTLE (n = 3) was accompanied by an upregulation of the protein on astrocyte membranes facing synapses in the neuropil, when compared with non-MTLE (n = 3). We propose that the altered distribution of MCT1 and MCT2 in TLE (especially MTLE) limits the flux of monocarboxylates across the blood-brain barrier and enhances the exchange of monocarboxylates within the brain parenchyma.
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Affiliation(s)
- Fredrik Lauritzen
- The Brain and Muscle Energy Group, Department of Anatomy and Centre for Molecular Biology and Neuroscience, University of Oslo, Blindern, NO-0317 Oslo, Norway
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Abstract
We present the perspective that lactate is a volume transmitter of cellular signals in brain that acutely and chronically regulate the energy metabolism of large neuronal ensembles. From this perspective, we interpret recent evidence to mean that lactate transmission serves the maintenance of network metabolism by two different mechanisms, one by regulating the formation of cAMP via the lactate receptor GPR81, the other by adjusting the NADH/NAD(+) redox ratios, both linked to the maintenance of brain energy turnover and possibly cerebral blood flow. The role of lactate as mediator of metabolic information rather than metabolic substrate answers a number of questions raised by the controversial oxidativeness of astrocytic metabolism and its contribution to neuronal function.
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Affiliation(s)
- Linda H Bergersen
- The Brain and Muscle Energy Group, Centre for Molecular Biology and Neuroscience, Institute for Basic Medical Sciences, University of Oslo, Oslo, Norway
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Bergersen LH, Morland C, Ormel L, Rinholm JE, Larsson M, Wold JFH, Røe AT, Stranna A, Santello M, Bouvier D, Ottersen OP, Volterra A, Gundersen V. Immunogold detection of L-glutamate and D-serine in small synaptic-like microvesicles in adult hippocampal astrocytes. ACTA ACUST UNITED AC 2011; 22:1690-7. [PMID: 21914633 DOI: 10.1093/cercor/bhr254] [Citation(s) in RCA: 83] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
Glutamate and the N-methyl-D-aspartate receptor ligand D-serine are putative gliotransmitters. Here, we show by immunogold cytochemistry of the adult hippocampus that glutamate and D-serine accumulate in synaptic-like microvesicles (SLMVs) in the perisynaptic processes of astrocytes. The estimated concentration of fixed glutamate in the astrocytic SLMVs is comparable to that in synaptic vesicles of excitatory nerve terminals (≈ 45 and ≈ 55 mM, respectively), whereas the D-serine level is about 6 mM. The vesicles are organized in small spaced clusters located near the astrocytic plasma membrane. Endoplasmic reticulum is regularly found in close vicinity to SLMVs, suggesting that astrocytes contain functional nanodomains, where a local Ca(2+) increase can trigger release of glutamate and/or D-serine.
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Affiliation(s)
- L H Bergersen
- Department of Anatomy, Centre for Molecular Biology and Neuroscience, Institute of Basic Medical Sciences, University of Oslo, 0317 Oslo, Norway
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Lauritzen F, Perez EL, Melillo ER, Roh JM, Zaveri HP, Lee TSW, Wang Y, Bergersen LH, Eid T. Altered expression of brain monocarboxylate transporter 1 in models of temporal lobe epilepsy. Neurobiol Dis 2011; 45:165-76. [PMID: 21856423 DOI: 10.1016/j.nbd.2011.08.001] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2011] [Revised: 07/15/2011] [Accepted: 08/03/2011] [Indexed: 12/22/2022] Open
Abstract
Monocarboxylate transporter 1 (MCT1) facilitates the transport of monocarboxylate fuels (lactate, pyruvate and ketone bodies) and acidic drugs, such as valproic acid, across cell membranes. We recently reported that MCT1 is deficient on microvessels in the epileptogenic hippocampal formation in patients with medication-refractory temporal lobe epilepsy (TLE). To further define the role of MCT1 in the pathophysiology of TLE, we used immunohistochemistry and stereological analysis to localize and quantify the transporter in the hippocampal formation in three novel and highly relevant rat models of TLE and in nonepileptic control animals. One model utilizes methionine sulfoximine to induce brain glutamine synthetase deficiency and recurrent limbic seizures, while two models employ an episode of perforant pathway stimulation to cause epilepsy. MCT1 was lost on microvessels and upregulated on astrocytes in the hippocampal formation in all models of TLE. Notably, the loss of MCT1 on microvessels was not due to a reduction in microvessel density. The similarities in MCT1 expression among human subjects with TLE and several animal models of the disease strongly suggest a critical role of this molecule in the pathogenesis of TLE. We hypothesize that the downregulation of MCT1 may promote seizures via impaired uptake of ketone bodies and antiepileptic drugs by the epileptogenic brain. We also propose that the overexpression of MCT1 on astrocytes may lead to increased uptake or release of monocarboxylates by these cells, with important implications for brain metabolism and excitability. These hypotheses can now be rigorously tested in several animal models that replicate key features of human TLE.
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Affiliation(s)
- Fredrik Lauritzen
- Department of Laboratory Medicine, Yale University School of Medicine, P.O. Box 208035, New Haven, CT 06520, USA
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Bergersen LH, Sander M, Storm-Mathisen J. What the nose knows, what the eyes see, how we feel, how we learn, how we understand motor acts, why "YY" is essential for ion transport, how epigenetics meet neurobiology in Rett syndrome: seven topics at the 2010 Kavli Prize Symposium on Neuroscience. Neuroscience 2011; 190:1-11. [PMID: 21624437 DOI: 10.1016/j.neuroscience.2011.05.036] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2011] [Accepted: 05/16/2011] [Indexed: 10/18/2022]
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Lauritzen KH, Cheng C, Wiksen H, Bergersen LH, Klungland A. Mitochondrial DNA toxicity compromises mitochondrial dynamics and induces hippocampal antioxidant defenses. DNA Repair (Amst) 2011; 10:639-53. [PMID: 21550321 DOI: 10.1016/j.dnarep.2011.04.011] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2010] [Revised: 03/18/2011] [Accepted: 04/06/2011] [Indexed: 11/20/2022]
Abstract
Mitochondria are highly dynamic organelles that can be actively transported within the cell to satisfy local requirements. They are vital for providing cellular energy, but are also an important endogenous source of reactive oxygen species. The distribution of mitochondria is particularly important for neurons because of the morphological complexity of these cells, and because neural processing is metabolically expensive. Defects in mitochondrial distribution, observed in several neurodegenerative diseases, can result in synaptic dysfunction. We have generated transgenic mice expressing an enzyme in forebrain neurons that causes mitochondrial DNA (mtDNA) damage in the form of abasic-sites, creating mtDNA toxicity. Here, we report that mitochondrial distribution is disturbed in hippocampal neurons of these mice. Moreover, mtDNA copy number and mitochondrial transcription are reduced, and oxidative stress is increased. There is also a loss of receptors at excitatory glutamatergic synapses in the dentate gyrus, and the size of the postsynaptic density in this region is abnormal. We speculate that the loss of synaptic mitochondria caused by accumulation in the neuronal cell body contributes to the observed synaptic abnormalities, as well as the overall loss of mtDNA and diminished mitochondrial transcription. Collectively, these changes lead to mitochondria with reduced function and increased oxidative stress.
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Affiliation(s)
- Knut H Lauritzen
- Centre for Molecular Biology and Neuroscience, Institute of Medical Microbiology, Oslo University Hospital and University of Oslo, NO-0027 Oslo, Norway
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Paulsen G, Lauritzen F, Bayer ML, Kalhovde JM, Ugelstad I, Owe SG, Hallén J, Bergersen LH, Raastad T. Subcellular movement and expression of HSP27, alphaB-crystallin, and HSP70 after two bouts of eccentric exercise in humans. J Appl Physiol (1985) 2009; 107:570-82. [PMID: 19498098 DOI: 10.1152/japplphysiol.00209.2009] [Citation(s) in RCA: 93] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
The aims of this study were to investigate the sarcomeric accumulation and expression of heat shock proteins (HSPs) after two bouts of maximal eccentric exercise. Twenty-four subjects performed two bouts of 70 maximal voluntary eccentric actions using the elbow flexors in one arm. The bouts were separated by 3 wk. The changes in concentric (60 degrees/s) and isometric (90 degrees) force-generating capacity were monitored for 9 days after each bout, and biopsies were taken 1 and 48 h and 4 and 7 days after bout 1 and 1 and 48 h after bout 2. The content of HSP27, alphaB-crystallin, HSP70, and desmin in the cytosolic and cytoskeleton/myofibrillar fractions of homogenized muscle samples was determined by immunoassays, and the cellular and subcellular localization of the HSPs in the myofibrillar structure was analyzed by conventional and confocal immunofluorescence microscopy and quantitative electron microscopy. The force-generating capacity was reduced by approximately 50% and did not recover completely during the 3 wk following bout 1. After bout 2, the subjects recovered within 4 days. The HSP levels increased in the cytosolic fraction after bout 1, especially HSP70 (approximately 300% 2-7 days after exercise). Increased levels of HSP27, alphaB-crystallin, and HSP70 were found in the cytoskeletal/myofibrillar fraction after both bouts, despite reduced damage after bout 2. At the ultrastructural level, HSP27 and alphaB-crystallin accumulated in Z-disks, in intermediate desmin-like structures (alphaB-crystallin), and in areas of myofibrillar disruption. In conclusion, HSP27 and alphaB-crystallin accumulated in myofibrillar structures, especially in the Z-disks and the intermediate structures (desmin). The function of the small HSPs is possibly to stabilize and protect the myofibrillar structures during and after unaccustomed eccentric exercise. The large amount of HSP27, alphaB-crystallin, and HSP70 in the cytoskeletal/myofibrillar fraction after a repeated bout of exercise suggests a protective role as part of the repeated-bout effect.
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Affiliation(s)
- G Paulsen
- Norwegian School of Sport Sciences, Department of Anatomy, University of Oslo, P.O. Box 4014 U.S., N-0806 Oslo, Norway.
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Owe SG, Jensen V, Evergren E, Ruiz A, Shupliakov O, Kullmann DM, Storm-Mathisen J, Walaas SI, Hvalby Ø, Bergersen LH. Synapsin- and actin-dependent frequency enhancement in mouse hippocampal mossy fiber synapses. Cereb Cortex 2008; 19:511-23. [PMID: 18550596 PMCID: PMC2638812 DOI: 10.1093/cercor/bhn101] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
The synapsin proteins have different roles in excitatory and inhibitory synaptic terminals. We demonstrate a differential role between types of excitatory terminals. Structural and functional aspects of the hippocampal mossy fiber (MF) synapses were studied in wild-type (WT) mice and in synapsin double-knockout mice (DKO). A severe reduction in the number of synaptic vesicles situated more than 100 nm away from the presynaptic membrane active zone was found in the synapsin DKO animals. The ultrastructural level gave concomitant reduction in F-actin immunoreactivity observed at the periactive endocytic zone of the MF terminals. Frequency facilitation was normal in synapsin DKO mice at low firing rates (approximately 0.1 Hz) but was impaired at firing rates within the physiological range (approximately 2 Hz). Synapses made by associational/commissural fibers showed comparatively small frequency facilitation at the same frequencies. Synapsin-dependent facilitation in MF synapses of WT mice was attenuated by blocking F-actin polymerization with cytochalasin B in hippocampal slices. Synapsin III, selectively seen in MF synapses, is enriched specifically in the area adjacent to the synaptic cleft. This may underlie the ability of synapsin III to promote synaptic depression, contributing to the reduced frequency facilitation observed in the absence of synapsins I and II.
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Affiliation(s)
- Simen G Owe
- Department of Anatomy, Institute of Basic Medical Sciences, University of Oslo, Oslo, Norway
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Jensen V, Rinholm JE, Johansen TJ, Medin T, Storm-Mathisen J, Sagvolden T, Hvalby O, Bergersen LH. N-methyl-D-aspartate receptor subunit dysfunction at hippocampal glutamatergic synapses in an animal model of attention-deficit/hyperactivity disorder. Neuroscience 2008; 158:353-64. [PMID: 18571865 DOI: 10.1016/j.neuroscience.2008.05.016] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2008] [Revised: 05/13/2008] [Accepted: 05/15/2008] [Indexed: 11/15/2022]
Abstract
Attention-deficit/hyperactivity disorder (ADHD) is the most common neurobehavioural disorder among children. ADHD children are hyperactive, impulsive and have problems with sustained attention. These cardinal features are also present in the best validated animal model of ADHD, the spontaneously hypertensive rat (SHR), which is derived from the Wistar Kyoto rat (WKY). Current theories of ADHD relate symptom development to factors that alter learning. N-methyl-D-aspartate receptor (NMDAR) dependent long term changes in synaptic efficacy in the mammalian CNS are thought to represent underlying cellular mechanisms for some forms of learning. We therefore hypothesized that synaptic abnormality in excitatory, glutamatergic synaptic transmission might contribute to the altered behavior in SHRs. We studied physiological and anatomical aspects of hippocampal CA3-to-CA1 synapses in age-matched SHR and WKY (controls). Electrophysiological analysis of these synapses showed reduced synaptic transmission (reduced field excitatory postsynaptic potential for a defined fiber volley size) in SHR, whereas short-term forms of synaptic plasticity, like paired-pulse facilitation, frequency facilitation, and delayed response enhancement were comparable in the two genotypes, and long-term potentiation (LTP) of synaptic transmission was of similar magnitude. However, LTP in SHR was significantly reduced (by 50%) by the NR2B specific blocker CP-101,606 (10 microM), whereas the blocker had no effect on LTP magnitude in the control rats. This indicates that the SHR has a functional predominance of NR2B, a feature characteristic of early developmental stages in these synapses. Quantitative immunofluorescence and electron microscopic postembedding immunogold cytochemistry of the three major NMDAR subunits (NR1, NR2A; and NR2B) in stratum radiatum spine synapses revealed no differences between SHR and WKY. The results indicate that functional impairments in glutamatergic synaptic transmission may be one of the underlying mechanisms leading to the abnormal behavior in SHR, and possibly in human ADHD.
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Affiliation(s)
- V Jensen
- Molecular Neurobiology Research Group, Institute of Basic Medical Sciences, University of Oslo, Oslo, Norway
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Bergersen LH, Gundersen V. Morphological evidence for vesicular glutamate release from astrocytes. Neuroscience 2008; 158:260-5. [PMID: 18479831 DOI: 10.1016/j.neuroscience.2008.03.074] [Citation(s) in RCA: 66] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2008] [Revised: 03/31/2008] [Accepted: 03/31/2008] [Indexed: 01/23/2023]
Abstract
There is now growing evidence that astrocytes, like neurons, can release transmitters. One transmitter that in a vast number of studies has been shown to be released from astrocytes is glutamate. Although asytrocytic glutamate may be released by several mechanisms, the evidence in favor of exocytosis is most compelling. Astrocytes may respond to neuronal activity by such exocytotic release of glutamate. The astrocyte derived glutamate can in turn activate neuronal glutamate receptors, in particular N-methyl-D-aspartate (NMDA) receptors. Here we review the morphological data supporting that astrocytes possess the machinery for exocytosis of glutamate. We describe the presence of small synaptic-like microvesicles, SNARE proteins and vesicular glutamate transporters in astrocytes, as well as NMDA receptors situated in vicinity of the astrocytic vesicles.
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Affiliation(s)
- L H Bergersen
- Department of Anatomy, Institute of Basic Medical Sciences, University of Oslo, POB 1105 Blindern, 0317 Oslo, Norway.
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Tonazzini I, Trincavelli ML, Storm-Mathisen J, Martini C, Bergersen LH. Co-localization and functional cross-talk between A1 and P2Y1 purine receptors in rat hippocampus. Eur J Neurosci 2007; 26:890-902. [PMID: 17672857 PMCID: PMC2121138 DOI: 10.1111/j.1460-9568.2007.05697.x] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
Adenosine and ATP, via their specific P1 and P2 receptors, modulate a wide variety of cellular and tissue functions, playing a neuroprotective or neurodegenerative role in brain damage conditions. Although, in general, adenosine inhibits excitability and ATP functions as an excitatory transmitter in the central nervous system, recent data suggest the existence of a heterodimerization and a functional interaction between P1 and P2 receptors in the brain. In particular, interactions of adenosine A1 and P2Y1 receptors may play important roles in the purinergic signalling cascade. In the present work, we investigated the subcellular localization/co-localization of the receptors and their functional cross-talk at the membrane level in Wistar rat hippocampus. This is a particularly vulnerable brain area, which is sensitive to adenosine- and ATP-mediated control of glutamatergic transmission. The postembedding immunogold electron microscopy technique showed that the two receptors are co-localized at the synaptic membranes and surrounding astroglial membranes of glutamatergic synapses. To investigate the functional cross-talk between the two types of purinergic receptors, we evaluated the reciprocal effects of their activation on their G protein coupling. P2Y1 receptor stimulation impaired the potency of A1 receptor coupling to G protein, whereas the stimulation of A1 receptors increased the functional responsiveness of P2Y1 receptors. The results demonstrated an A1-P2Y1 receptor co-localization at glutamatergic synapses and surrounding astrocytes and a functional interaction between these receptors in hippocampus, suggesting ATP and adenosine can interact in purine-mediated signalling. This may be particularly important during pathological conditions, when large amounts of these mediators are released.
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Affiliation(s)
- I Tonazzini
- Department of Psychiatry Neurobiology Pharmacology and Biotechnology, University of Pisa, 56126, Pisa, Italy
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Bergersen LH. Is lactate food for neurons? Comparison of monocarboxylate transporter subtypes in brain and muscle. Neuroscience 2007; 145:11-9. [PMID: 17218064 DOI: 10.1016/j.neuroscience.2006.11.062] [Citation(s) in RCA: 168] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2006] [Revised: 11/08/2006] [Accepted: 11/21/2006] [Indexed: 10/23/2022]
Abstract
Intercellular monocarboxylate transport is important, particularly in tissues with high energy demands, such as brain and muscle. In skeletal muscle, it is well established that glycolytic fast twitch muscle fibers produce lactate, which is transported out of the cell through the monocarboxylate transporter (MCT) 4. Lactate is then taken up and oxidized by the oxidative slow twitch muscle fibers, which express MCT1. In the brain it is still questioned whether lactate produced in astrocytes is taken up and oxidized by neurons upon activation. Several studies have reported that astrocytes express MCT4, whereas neurons express MCT2. By comparing the localizations of MCTs in oxidative and glycolytic compartments I here give support to the idea that there is a lactate shuttle in the brain similar to that in muscle. This conclusion is based on studies in rodents using high resolution immunocytochemical methods at the light and electron microscopical levels.
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Affiliation(s)
- L H Bergersen
- Centre for Molecular Biology and Neuroscience, and Department of Anatomy, IBM, University of Oslo, Domus Medica, Room 1293, Songsvannsveien 9, POB 1105 Blindern, N-0317 Oslo, Norway.
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Jourdain P, Bergersen LH, Bhaukaurally K, Bezzi P, Santello M, Domercq M, Matute C, Tonello F, Gundersen V, Volterra A. Glutamate exocytosis from astrocytes controls synaptic strength. Nat Neurosci 2007; 10:331-9. [PMID: 17310248 DOI: 10.1038/nn1849] [Citation(s) in RCA: 592] [Impact Index Per Article: 34.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2006] [Accepted: 01/16/2007] [Indexed: 01/07/2023]
Abstract
The release of transmitters from glia influences synaptic functions. The modalities and physiological functions of glial release are poorly understood. Here we show that glutamate exocytosis from astrocytes of the rat hippocampal dentate molecular layer enhances synaptic strength at excitatory synapses between perforant path afferents and granule cells. The effect is mediated by ifenprodil-sensitive NMDA ionotropic glutamate receptors and involves an increase of transmitter release at the synapse. Correspondingly, we identify NMDA receptor 2B subunits on the extrasynaptic portion of excitatory nerve terminals. The receptor distribution is spatially related to glutamate-containing synaptic-like microvesicles in the apposed astrocytic processes. This glial regulatory pathway is endogenously activated by neuronal activity-dependent stimulation of purinergic P2Y1 receptors on the astrocytes. Thus, we provide the first combined functional and ultrastructural evidence for a physiological control of synaptic activity via exocytosis of glutamate from astrocytes.
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Affiliation(s)
- Pascal Jourdain
- Department of Cell Biology and Morphology, University of Lausanne, Rue du Bugnon 9, 1005 Lausanne, Switzerland
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Rinholm JE, Slettaløkken G, Marcaggi P, Skare Ø, Storm-Mathisen J, Bergersen LH. Subcellular localization of the glutamate transporters GLAST and GLT at the neuromuscular junction in rodents. Neuroscience 2007; 145:579-91. [PMID: 17289278 DOI: 10.1016/j.neuroscience.2006.12.041] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2006] [Revised: 12/15/2006] [Accepted: 12/19/2006] [Indexed: 11/26/2022]
Abstract
The vertebrate neuromuscular junction (NMJ) is known to be a cholinergic synapse at which acetylcholine (ACh) is released from the presynaptic terminal to act on postsynaptic nicotinic ACh receptors. There is now growing evidence that glutamate, which is the main excitatory transmitter in the CNS and at invertebrate NMJs, may have a signaling function together with ACh also at the vertebrate NMJ. In the CNS, the extracellular concentration of glutamate is kept at a subtoxic level by Na(+)-driven high-affinity glutamate transporters located in plasma membranes of astrocytes and neurons. The glutamate transporters are also pivotal for shaping glutamate receptor responses at synapses. In order to throw further light on the potential role of glutamate as a cotransmitter at the NMJ we used high-resolution immunocytochemical methods to investigate the localization of the plasma membrane glutamate transporters GLAST (glutamate aspartate transporter) and GLT (glutamate transporter 1) in rat and mice NMJ regions. Confocal laser-scanning immunocytochemistry showed that GLT is restricted to the NMJ in rat and mouse skeletal muscle. Lack of labeling signal in knock-out mice confirmed that the immunoreactivity observed at the NMJ was specific for GLT. GLAST was also localized at the NMJ in rat but not detected in mouse NMJ (while abundant in mouse brain). Post-embedding electron microscopic immunocytochemistry and quantitative analyses in rat showed that GLAST and GLT are enriched in the junctional folds of the postsynaptic membrane at the NMJ. GLT was relatively higher in the slow-twitch muscle soleus than in the fast-twitch muscle extensor digitorum longus, whereas GLAST was relatively higher in extensor digitorum longus than in soleus. The findings show--together with previous demonstration of vesicular glutamate, a vesicular glutamate transporter and glutamate receptors--that mammalian NMJs contain the machinery required for synaptic release and action of glutamate. This indicates a signaling role for glutamate at the normal NMJ and provides a basis for the ability of denervated muscle to be reinnervated by glutamatergic axons from the CNS.
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MESH Headings
- Animals
- Excitatory Amino Acid Transporter 1/genetics
- Excitatory Amino Acid Transporter 1/metabolism
- Excitatory Amino Acid Transporter 2/genetics
- Excitatory Amino Acid Transporter 2/metabolism
- Glutamic Acid/metabolism
- Immunohistochemistry
- Male
- Mice
- Mice, Inbred C57BL
- Mice, Knockout
- Microscopy, Confocal
- Microscopy, Immunoelectron
- Motor Neurons/metabolism
- Motor Neurons/ultrastructure
- Muscle Fibers, Fast-Twitch/metabolism
- Muscle Fibers, Fast-Twitch/ultrastructure
- Muscle Fibers, Slow-Twitch/metabolism
- Muscle Fibers, Slow-Twitch/ultrastructure
- Muscle, Skeletal/innervation
- Neuromuscular Junction/metabolism
- Neuromuscular Junction/ultrastructure
- Rats
- Rats, Wistar
- Signal Transduction/physiology
- Species Specificity
- Synaptic Membranes/metabolism
- Synaptic Membranes/ultrastructure
- Synaptic Transmission/physiology
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Affiliation(s)
- J E Rinholm
- Department of Anatomy and Centre for Molecular Biology and Neuroscience, University of Oslo, P.O. Box 1105 Blindern, N0317 Oslo, Norway
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Gylterud Owe S, Bogen IL, Walaas SI, Storm-Mathisen J, Bergersen LH. Ultrastructural quantification of glutamate receptors at excitatory synapses in hippocampus of synapsin I+II double knock-out mice. Neuroscience 2006; 136:769-77. [PMID: 16344150 DOI: 10.1016/j.neuroscience.2005.08.056] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2005] [Revised: 08/19/2005] [Accepted: 08/27/2005] [Indexed: 10/25/2022]
Abstract
Previous findings, mainly in in vitro systems, have shown that the density of vesicles and the synaptic efficacy at excitatory synapses are reduced in the absence of synapsins, despite the fact that transgenic mice lacking synapsins develop an epileptic phenotype. Here we study glutamate receptors by quantitative immunoblotting and by quantitative electron microscopic postembedding immunocytochemistry in hippocampus of perfusion fixed control wild type and double knock-out mice lacking synapsins I and II. In wild type hippocampus the densities of alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor subunits were higher (indicated for glutamate receptor subunit 1, highly significant for glutamate receptor subunits 2/3) in mossy fiber-to-cornu ammonis 3 pyramidal cell synapses than in the Schaffer collateral/commissural-to-cornu ammonis 1 pyramidal cell synapses, the two synapse categories that carry the main excitatory throughput of the hippocampus. The opposite was true for N-methyl-D-aspartate receptors. The difference in localization of glutamate receptor subunit 1 receptor subunits was increased in the double knock-out mice while there was no change in the overall expression of the glutamate receptors in hippocampus as shown by quantitative Western blotting. The increased level of glutamate receptor subunit 1 at the mossy fiber-to-cornu ammonis 3 pyramidal cell synapse may result in alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptors with reduced proportions of glutamate receptor subunit 2, and hence increased Ca2+ influx, which could cause increased excitability despite of impaired synaptic function (cf. [Krestel HE, Shimshek DR, Jensen V, Nevian T, Kim J, Geng Y, Bast T, Depaulis A, Schonig K, Schwenk F, Bujard H, Hvalby O, Sprengel R, Seeburg PH (2004) A genetic switch for epilepsy in adult mice. J Neurosci 24:10568-10578]), possibly underlying the seizure proneness in the synapsin double knock-out mice. In addition, the tendency to increased predominance of N-methyl-d-aspartate receptors at the main type of excitatory synapse onto cornu ammonis 1 pyramidal cells might contribute to the seizure susceptibility of the synapsin deficient mice. The results showed no significant changes in the proportion of 'silent' Schaffer collateral/commissural synapses lacking alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptors or in the synaptic membrane size, indicating that plasticity involving these parameters is not preferentially triggered due to lack of synapsins.
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Affiliation(s)
- S Gylterud Owe
- Department of Anatomy and Centre for Molecular Biology and Neuroscience CMBN, University of Oslo, P.O. Box 1105 Blindern, N0317 Oslo, Norway
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50
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Káradóttir R, Cavelier P, Bergersen LH, Attwell D. NMDA receptors are expressed in oligodendrocytes and activated in ischaemia. Nature 2006; 438:1162-6. [PMID: 16372011 PMCID: PMC1416283 DOI: 10.1038/nature04302] [Citation(s) in RCA: 555] [Impact Index Per Article: 30.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2005] [Accepted: 10/10/2005] [Indexed: 11/09/2022]
Abstract
Glutamate-mediated damage to oligodendrocytes contributes to mental or physical impairment in periventricular leukomalacia (pre- or perinatal white matter injury leading to cerebral palsy), spinal cord injury, multiple sclerosis and stroke. Unlike neurons, white matter oligodendrocytes reportedly lack NMDA (N-methyl-d-aspartate) receptors. It is believed that glutamate damages oligodendrocytes, especially their precursor cells, by acting on calcium-permeable AMPA (alpha-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid)/kainate receptors alone or by reversing cystine-glutamate exchange and depriving cells of antioxidant protection. Here we show that precursor, immature and mature oligodendrocytes in the white matter of the cerebellum and corpus callosum exhibit NMDA-evoked currents, mediated by receptors that are blocked only weakly by Mg2+ and that may contain NR1, NR2C and NR3 NMDA receptor subunits. NMDA receptors are present in the myelinating processes of oligodendrocytes, where the small intracellular space could lead to a large rise in intracellular ion concentration in response to NMDA receptor activation. Simulating ischaemia led to development of an inward current in oligodendrocytes, which was partly mediated by NMDA receptors. These results point to NMDA receptors of unusual subunit composition as a potential therapeutic target for preventing white matter damage in a variety of diseases.
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Affiliation(s)
| | | | | | - David Attwell
- Send correspondence to: David Attwell, Dept. Physiology, University College London, Gower St., London, WC1E 6BT, England, Tel: (+44)-20-7679-7342; Fax: (+44)-20-7383-7005; E-mail
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