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Corales LG, Inada H, Owada Y, Osumi N. Fatty acid preference for beta-oxidation in mitochondria of murine cultured astrocytes. Genes Cells 2024. [PMID: 38965717 DOI: 10.1111/gtc.13144] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2024] [Revised: 06/24/2024] [Accepted: 06/26/2024] [Indexed: 07/06/2024]
Abstract
The brain utilizes glucose as a primary energy substrate but also fatty acids for the β-oxidation in mitochondria. The β-oxidation is reported to occur mainly in astrocytes, but its capacity and efficacy against different fatty acids remain unknown. Here, we show the fatty acid preference for the β-oxidation in mitochondria of murine cultured astrocytes. Fatty acid oxidation assay using an extracellular flux analyzer showed that saturated or monosaturated fatty acids, palmitic acid and oleic acid, are preferred substrates over polyunsaturated fatty acids like arachidonic acid and docosahexaenoic acid. We also report that fatty acid binding proteins expressed in the astrocytes contribute less to fatty acid transport to mitochondria for β-oxidation. Our results could give insight into understanding energy metabolism through fatty acid consumption in the brain.
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Affiliation(s)
- Laarni Grace Corales
- Department of Developmental Neuroscience, Graduate School of Medicine, Tohoku University, Sendai, Japan
| | - Hitoshi Inada
- Department of Developmental Neuroscience, Graduate School of Medicine, Tohoku University, Sendai, Japan
- Department of Biochemistry and Cellular Biology, National Center of Neurology and Psychiatry, Tokyo, Japan
| | - Yuji Owada
- Department of Organ Anatomy, Graduate School of Medicine, Tohoku University, Sendai, Japan
| | - Noriko Osumi
- Department of Developmental Neuroscience, Graduate School of Medicine, Tohoku University, Sendai, Japan
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2
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Radford-Smith D, Ng TT, Yates AG, Dunstan I, Claridge TDW, Anthony DC, Probert F. Ex-Vivo 13C NMR Spectroscopy of Rodent Brain: TNF Restricts Neuronal Utilization of Astrocyte-Derived Metabolites. J Proteome Res 2024. [PMID: 38943617 DOI: 10.1021/acs.jproteome.4c00035] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/01/2024]
Abstract
Tumor necrosis factor (TNF) has well-established roles in neuroinflammatory disorders, but the effect of TNF on the biochemistry of brain cells remains poorly understood. Here, we microinjected TNF into the brain to study its impact on glial and neuronal metabolism (glycolysis, pentose phosphate pathway, citric acid cycle, pyruvate dehydrogenase, and pyruvate carboxylase pathways) using 13C NMR spectroscopy on brain extracts following intravenous [1,2-13C]-glucose (to probe glia and neuron metabolism), [2-13C]-acetate (probing astrocyte-specific metabolites), or [3-13C]-lactate. An increase in [4,5-13C]-glutamine and [2,3-13C]-lactate coupled with a decrease in [4,5-13C]-glutamate was observed in the [1,2-13C]-glucose-infused animals treated with TNF. As glutamine is produced from glutamate by astrocyte-specific glutamine synthetase the increase in [4,5-13C]-glutamine reflects increased production of glutamine by astrocytes. This was confirmed by infusion with astrocyte substrate [2-13C]-acetate. As lactate is metabolized in the brain to produce glutamate, the simultaneous increase in [2,3-13C]-lactate and decrease in [4,5-13C]-glutamate suggests decreased lactate utilization, which was confirmed using [3-13C]-lactate as a metabolic precursor. These results suggest that TNF rearranges the metabolic network, disrupting the energy supply chain perturbing the glutamine-glutamate shuttle between astrocytes and the neurons. These insights pave the way for developing astrocyte-targeted therapeutic strategies aimed at modulating effects of TNF to restore metabolic homeostasis in neuroinflammatory disorders.
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Affiliation(s)
- Daniel Radford-Smith
- Department of Chemistry, University of Oxford, Oxford OX1 3TA, U.K
- Pharmacology Department, University of Oxford, Oxford OX1 3QT, U.K
| | - Tang T Ng
- Department of Chemistry, University of Oxford, Oxford OX1 3TA, U.K
| | - Abi G Yates
- Department of Chemistry, University of Oxford, Oxford OX1 3TA, U.K
- Pharmacology Department, University of Oxford, Oxford OX1 3QT, U.K
| | - Isobel Dunstan
- Pharmacology Department, University of Oxford, Oxford OX1 3QT, U.K
| | | | - Daniel C Anthony
- Pharmacology Department, University of Oxford, Oxford OX1 3QT, U.K
| | - Fay Probert
- Department of Chemistry, University of Oxford, Oxford OX1 3TA, U.K
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3
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Kim D, Lee SH, Hwang HS, Kim SJ, Yun M. Recent Update on PET/CT Radiotracers for Imaging Cerebral Glioma. Nucl Med Mol Imaging 2024; 58:237-245. [PMID: 38932755 PMCID: PMC11196511 DOI: 10.1007/s13139-024-00847-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2023] [Revised: 01/16/2024] [Accepted: 01/29/2024] [Indexed: 06/28/2024] Open
Abstract
Positron emission tomography/computed tomography (PET/CT) has dramatically altered the landscape of noninvasive glioma evaluation, offering complementary insights to those gained through magnetic resonance imaging (MRI). PET/CT scans enable a multifaceted analysis of glioma biology, supporting clinical applications from grading and differential diagnosis to mapping the full extent of tumors and planning subsequent treatments and evaluations. With a broad array of specialized radiotracers, researchers and clinicians can now probe various biological characteristics of gliomas, such as glucose utilization, cellular proliferation, oxygen deficiency, amino acid trafficking, and reactive astrogliosis. This review aims to provide a recent update on the application of versatile PET/CT radiotracers in glioma research and clinical practice.
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Affiliation(s)
- Dongwoo Kim
- Department of Nuclear Medicine, Severance Hospital, Yonsei University College of Medicine, 50-1 Yonsei-Ro, Seodaemun-Gu, Seoul, 03722 Republic of Korea
| | - Suk-Hyun Lee
- Department of Radiology, Hallym University Kangnam Sacred Heart Hospital, Hallym University College of Medicine, Seoul, 07441 Republic of Korea
| | - Hee Sung Hwang
- Department of Nuclear Medicine, Hallym University Sacred Heart Hospital, Hallym University College of Medicine, Anyang, 14068 Republic of Korea
| | - Sun Jung Kim
- Department of Nuclear Medicine, National Health Insurance Service Ilsan Hospital, Goyang, 10444 Republic of Korea
| | - Mijin Yun
- Department of Nuclear Medicine, Severance Hospital, Yonsei University College of Medicine, 50-1 Yonsei-Ro, Seodaemun-Gu, Seoul, 03722 Republic of Korea
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4
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Kim D, Ko HY, Chung JI, Park YM, Lee S, Kim SY, Kim J, Chun JH, Han KS, Lee M, Ju YH, Park SJ, Park KD, Nam MH, Kim SH, Shim JK, Park Y, Lim H, Park J, Lee GH, Kim H, Kim S, Park U, Ryu H, Lee SY, Park S, Kang SG, Chang JH, Lee CJ, Yun M. Visualizing cancer-originating acetate uptake through monocarboxylate transporter 1 in reactive astrocytes in the glioblastoma tumor microenvironment. Neuro Oncol 2024; 26:843-857. [PMID: 38085571 PMCID: PMC11066945 DOI: 10.1093/neuonc/noad243] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/04/2024] Open
Abstract
BACKGROUND Reactive astrogliosis is a hallmark of various brain pathologies, including neurodegenerative diseases and glioblastomas. However, the specific intermediate metabolites contributing to reactive astrogliosis remain unknown. This study investigated how glioblastomas induce reactive astrogliosis in the neighboring microenvironment and explore 11C-acetate PET as an imaging technique for detecting reactive astrogliosis. METHODS Through in vitro, mouse models, and human tissue experiments, we examined the association between elevated 11C-acetate uptake and reactive astrogliosis in gliomas. We explored acetate from glioblastoma cells, which triggers reactive astrogliosis in neighboring astrocytes by upregulating MAO-B and monocarboxylate transporter 1 (MCT1) expression. We evaluated the presence of cancer stem cells in the reactive astrogliosis region of glioblastomas and assessed the correlation between the volume of 11C-acetate uptake beyond MRI and prognosis. RESULTS Elevated 11C-acetate uptake is associated with reactive astrogliosis and astrocytic MCT1 in the periphery of glioblastomas in human tissues and mouse models. Glioblastoma cells exhibit increased acetate production as a result of glucose metabolism, with subsequent secretion of acetate. Acetate derived from glioblastoma cells induces reactive astrogliosis in neighboring astrocytes by increasing the expression of MAO-B and MCT1. We found cancer stem cells within the reactive astrogliosis at the tumor periphery. Consequently, a larger volume of 11C-acetate uptake beyond contrast-enhanced MRI was associated with a worse prognosis. CONCLUSIONS Our results highlight the role of acetate derived from glioblastoma cells in inducing reactive astrogliosis and underscore the potential value of 11C-acetate PET as an imaging technique for detecting reactive astrogliosis, offering important implications for the diagnosis and treatment of glioblastomas.
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Affiliation(s)
- Dongwoo Kim
- Department of Nuclear Medicine, Severance Hospital, Yonsei University College of Medicine, Seoul, Republic of Korea
| | - Hae Young Ko
- Department of Nuclear Medicine, Severance Hospital, Yonsei University College of Medicine, Seoul, Republic of Korea
| | - Jee-In Chung
- Department of Nuclear Medicine, Severance Hospital, Yonsei University College of Medicine, Seoul, Republic of Korea
| | - Yongmin Mason Park
- Center for Cognition and Sociality, Institute for Basic Science, Daejeon, Republic of Korea
- IBS School, University of Science and Technology, Daejeon, Republic of Korea
| | - Sangwon Lee
- Department of Nuclear Medicine, Severance Hospital, Yonsei University College of Medicine, Seoul, Republic of Korea
| | - Seon Yoo Kim
- Department of Nuclear Medicine, Severance Hospital, Yonsei University College of Medicine, Seoul, Republic of Korea
| | - Jisu Kim
- Department of Nuclear Medicine, Severance Hospital, Yonsei University College of Medicine, Seoul, Republic of Korea
| | - Joong-Hyun Chun
- Department of Nuclear Medicine, Severance Hospital, Yonsei University College of Medicine, Seoul, Republic of Korea
| | - Kyung-Seok Han
- Department of Biological Sciences, Chungnam National University, Daejeon, Republic of Korea
| | - Misu Lee
- Division of Life Science, College of Life Science and Bioengineering, Incheon National University, Incheon, Republic of Korea
| | - Yeon Ha Ju
- Center for Cognition and Sociality, Institute for Basic Science, Daejeon, Republic of Korea
- IBS School, University of Science and Technology, Daejeon, Republic of Korea
- Brain Science Institute, Korea Institute of Science and Technology (KIST), Seoul, Republic of Korea
| | - Sun Jun Park
- Brain Science Institute, Korea Institute of Science and Technology (KIST), Seoul, Republic of Korea
- Division of Bio-Med Science & Technology, KIST School, Korea University of Science and Technology, Seoul, Republic of Korea
| | - Ki Duk Park
- Brain Science Institute, Korea Institute of Science and Technology (KIST), Seoul, Republic of Korea
- Division of Bio-Med Science & Technology, KIST School, Korea University of Science and Technology, Seoul, Republic of Korea
| | - Min-Ho Nam
- Brain Science Institute, Korea Institute of Science and Technology (KIST), Seoul, Republic of Korea
- Division of Bio-Med Science & Technology, KIST School, Korea University of Science and Technology, Seoul, Republic of Korea
- Department of KHU-KIST Convergence Science and Technology, Kyung Hee University, Seoul, Republic of Korea
| | - Se Hoon Kim
- Department of Pathology, Severance Hospital, Yonsei University College of Medicine, Seoul, Republic of Korea
| | - Jin-Kyoung Shim
- Department of Neurosurgery, Severance Hospital, Yonsei University College of Medicine, Seoul, Republic of Korea
| | - Youngjoo Park
- Yonsei University College of Medicine, Seoul, Republic of Korea
| | - Hyunkeong Lim
- Department of Nuclear Medicine, Severance Hospital, Yonsei University College of Medicine, Seoul, Republic of Korea
| | - Jaekyung Park
- Department of Nuclear Medicine, Severance Hospital, Yonsei University College of Medicine, Seoul, Republic of Korea
| | - Gwan-Ho Lee
- Research Resources Division, Korea Institute of Science and Technology (KIST), Seoul, Republic of Korea
| | - Hyunjin Kim
- Brain Science Institute, Korea Institute of Science and Technology (KIST), Seoul, Republic of Korea
| | - Suhyun Kim
- K-Laboratory, Brain Science Institute, Korea Institute of Science and Technology (KIST), Seoul, Republic of Korea
| | - Uiyeol Park
- K-Laboratory, Brain Science Institute, Korea Institute of Science and Technology (KIST), Seoul, Republic of Korea
| | - Hoon Ryu
- K-Laboratory, Brain Science Institute, Korea Institute of Science and Technology (KIST), Seoul, Republic of Korea
| | - So Yun Lee
- Natural Products Research Institute, College of Pharmacy, Seoul National University, Seoul, Republic of Korea
| | - Sunghyouk Park
- Natural Products Research Institute, College of Pharmacy, Seoul National University, Seoul, Republic of Korea
| | - Seok-Gu Kang
- Department of Neurosurgery, Severance Hospital, Yonsei University College of Medicine, Seoul, Republic of Korea
| | - Jong Hee Chang
- Department of Neurosurgery, Severance Hospital, Yonsei University College of Medicine, Seoul, Republic of Korea
| | - C Justin Lee
- IBS School, University of Science and Technology, Daejeon, Republic of Korea
| | - Mijin Yun
- Department of Nuclear Medicine, Severance Hospital, Yonsei University College of Medicine, Seoul, Republic of Korea
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5
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Rae CD, Baur JA, Borges K, Dienel G, Díaz-García CM, Douglass SR, Drew K, Duarte JMN, Duran J, Kann O, Kristian T, Lee-Liu D, Lindquist BE, McNay EC, Robinson MB, Rothman DL, Rowlands BD, Ryan TA, Scafidi J, Scafidi S, Shuttleworth CW, Swanson RA, Uruk G, Vardjan N, Zorec R, McKenna MC. Brain energy metabolism: A roadmap for future research. J Neurochem 2024; 168:910-954. [PMID: 38183680 PMCID: PMC11102343 DOI: 10.1111/jnc.16032] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2023] [Revised: 11/29/2023] [Accepted: 12/05/2023] [Indexed: 01/08/2024]
Abstract
Although we have learned much about how the brain fuels its functions over the last decades, there remains much still to discover in an organ that is so complex. This article lays out major gaps in our knowledge of interrelationships between brain metabolism and brain function, including biochemical, cellular, and subcellular aspects of functional metabolism and its imaging in adult brain, as well as during development, aging, and disease. The focus is on unknowns in metabolism of major brain substrates and associated transporters, the roles of insulin and of lipid droplets, the emerging role of metabolism in microglia, mysteries about the major brain cofactor and signaling molecule NAD+, as well as unsolved problems underlying brain metabolism in pathologies such as traumatic brain injury, epilepsy, and metabolic downregulation during hibernation. It describes our current level of understanding of these facets of brain energy metabolism as well as a roadmap for future research.
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Affiliation(s)
- Caroline D. Rae
- School of Psychology, The University of New South Wales, NSW 2052 & Neuroscience Research Australia, Randwick, New South Wales, Australia
| | - Joseph A. Baur
- Department of Physiology and Institute for Diabetes, Obesity and Metabolism, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Karin Borges
- School of Biomedical Sciences, Faculty of Medicine, The University of Queensland, St Lucia, QLD, Australia
| | - Gerald Dienel
- Department of Neurology, University of Arkansas for Medical Sciences, Little Rock, Arkansas, USA
- Department of Cell Biology and Physiology, University of New Mexico School of Medicine, Albuquerque, New Mexico, USA
| | - Carlos Manlio Díaz-García
- Department of Biochemistry and Molecular Biology, Center for Geroscience and Healthy Brain Aging, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, USA
| | | | - Kelly Drew
- Center for Transformative Research in Metabolism, Institute of Arctic Biology, University of Alaska Fairbanks, Fairbanks, Alaska, USA
| | - João M. N. Duarte
- Department of Experimental Medical Science, Faculty of Medicine, Lund University, Lund, & Wallenberg Centre for Molecular Medicine, Lund University, Lund, Sweden
| | - Jordi Duran
- Institut Químic de Sarrià (IQS), Universitat Ramon Llull (URL), Barcelona, Spain
- Institute for Bioengineering of Catalonia (IBEC), The Barcelona Institute of Science and Technology, Barcelona, Spain
| | - Oliver Kann
- Institute of Physiology and Pathophysiology, University of Heidelberg, D-69120; Interdisciplinary Center for Neurosciences (IZN), University of Heidelberg, Heidelberg, Germany
| | - Tibor Kristian
- Veterans Affairs Maryland Health Center System, Baltimore, Maryland, USA
- Department of Anesthesiology and the Center for Shock, Trauma, and Anesthesiology Research (S.T.A.R.), University of Maryland School of Medicine, Baltimore, Maryland, USA
| | - Dasfne Lee-Liu
- Facultad de Medicina y Ciencia, Universidad San Sebastián, Santiago, Región Metropolitana, Chile
| | - Britta E. Lindquist
- Department of Neurology, Division of Neurocritical Care, Gladstone Institute of Neurological Disease, University of California at San Francisco, San Francisco, California, USA
| | - Ewan C. McNay
- Behavioral Neuroscience, University at Albany, Albany, New York, USA
| | - Michael B. Robinson
- Departments of Pediatrics and System Pharmacology & Translational Therapeutics, Children’s Hospital of Philadelphia, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Douglas L. Rothman
- Magnetic Resonance Research Center and Departments of Radiology and Biomedical Engineering, Yale University, New Haven, Connecticut, USA
| | - Benjamin D. Rowlands
- School of Chemistry, Faculty of Science, The University of Sydney, Sydney, New South Wales, Australia
| | - Timothy A. Ryan
- Department of Biochemistry, Weill Cornell Medicine, New York, New York, USA
| | - Joseph Scafidi
- Department of Neurology, Kennedy Krieger Institute, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Susanna Scafidi
- Anesthesiology & Critical Care Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - C. William Shuttleworth
- Department of Neurosciences, University of New Mexico School of Medicine Albuquerque, Albuquerque, New Mexico, USA
| | - Raymond A. Swanson
- Department of Neurology, University of California, San Francisco, and San Francisco Veterans Affairs Medical Center, San Francisco, California, USA
| | - Gökhan Uruk
- Department of Neurology, University of California, San Francisco, and San Francisco Veterans Affairs Medical Center, San Francisco, California, USA
| | - Nina Vardjan
- Laboratory of Cell Engineering, Celica Biomedical, Ljubljana, Slovenia
- Laboratory of Neuroendocrinology—Molecular Cell Physiology, Institute of Pathophysiology, Faculty of Medicine, University of Ljubljana, Ljubljana, Slovenia
| | - Robert Zorec
- Laboratory of Cell Engineering, Celica Biomedical, Ljubljana, Slovenia
- Laboratory of Neuroendocrinology—Molecular Cell Physiology, Institute of Pathophysiology, Faculty of Medicine, University of Ljubljana, Ljubljana, Slovenia
| | - Mary C. McKenna
- Department of Pediatrics and Program in Neuroscience, University of Maryland School of Medicine, Baltimore, Maryland, USA
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6
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Wen X, Dong H, Zou W. The role of gut microorganisms and metabolites in intracerebral hemorrhagic stroke: a comprehensive review. Front Neurosci 2024; 18:1346184. [PMID: 38449739 PMCID: PMC10915040 DOI: 10.3389/fnins.2024.1346184] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2023] [Accepted: 02/09/2024] [Indexed: 03/08/2024] Open
Abstract
Intracerebral hemorrhagic stroke, characterized by acute hemorrhage in the brain, has a significant clinical prevalence and poses a substantial threat to individuals' well-being and productivity. Recent research has elucidated the role of gut microorganisms and their metabolites in influencing brain function through the microbiota-gut-brain axis (MGBA). This article provides a comprehensive review of the current literature on the common metabolites, short-chain fatty acids (SCFAs) and trimethylamine-N-oxide (TMAO), produced by gut microbiota. These metabolites have demonstrated the potential to traverse the blood-brain barrier (BBB) and directly impact brain tissue. Additionally, these compounds have the potential to modulate the parasympathetic nervous system, thereby facilitating the release of pertinent substances, impeding the buildup of inflammatory agents within the brain, and manifesting anti-inflammatory properties. Furthermore, this scholarly analysis delves into the existing dearth of investigations concerning the influence of gut microorganisms and their metabolites on cerebral functions, while also highlighting prospective avenues for future research.
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Affiliation(s)
- Xin Wen
- The First Clinical Medical College, Heilongjiang University Of Chinese Medicine, Harbin, China
| | - Hao Dong
- The First Clinical Medical College, Heilongjiang University Of Chinese Medicine, Harbin, China
| | - Wei Zou
- The First Affiliated Hospital of Heilongjiang University of Chinese Medicine, Harbin, China
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7
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Nam MH, Ko HY, Kim D, Lee S, Park YM, Hyeon SJ, Won W, Chung JI, Kim SY, Jo HH, Oh KT, Han YE, Lee GH, Ju YH, Lee H, Kim H, Heo J, Bhalla M, Kim KJ, Kwon J, Stein TD, Kong M, Lee H, Lee SE, Oh SJ, Chun JH, Park MA, Park KD, Ryu H, Yun M, Lee CJ. Visualizing reactive astrocyte-neuron interaction in Alzheimer's disease using 11C-acetate and 18F-FDG. Brain 2023; 146:2957-2974. [PMID: 37062541 PMCID: PMC10517195 DOI: 10.1093/brain/awad037] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2022] [Revised: 01/04/2023] [Accepted: 01/23/2023] [Indexed: 04/18/2023] Open
Abstract
Reactive astrogliosis is a hallmark of Alzheimer's disease (AD). However, a clinically validated neuroimaging probe to visualize the reactive astrogliosis is yet to be discovered. Here, we show that PET imaging with 11C-acetate and 18F-fluorodeoxyglucose (18F-FDG) functionally visualizes the reactive astrocyte-mediated neuronal hypometabolism in the brains with neuroinflammation and AD. To investigate the alterations of acetate and glucose metabolism in the diseased brains and their impact on the AD pathology, we adopted multifaceted approaches including microPET imaging, autoradiography, immunohistochemistry, metabolomics, and electrophysiology. Two AD rodent models, APP/PS1 and 5xFAD transgenic mice, one adenovirus-induced rat model of reactive astrogliosis, and post-mortem human brain tissues were used in this study. We further curated a proof-of-concept human study that included 11C-acetate and 18F-FDG PET imaging analyses along with neuropsychological assessments from 11 AD patients and 10 healthy control subjects. We demonstrate that reactive astrocytes excessively absorb acetate through elevated monocarboxylate transporter-1 (MCT1) in rodent models of both reactive astrogliosis and AD. The elevated acetate uptake is associated with reactive astrogliosis and boosts the aberrant astrocytic GABA synthesis when amyloid-β is present. The excessive astrocytic GABA subsequently suppresses neuronal activity, which could lead to glucose uptake through decreased glucose transporter-3 in the diseased brains. We further demonstrate that 11C-acetate uptake was significantly increased in the entorhinal cortex, hippocampus and temporo-parietal neocortex of the AD patients compared to the healthy controls, while 18F-FDG uptake was significantly reduced in the same regions. Additionally, we discover a strong correlation between the patients' cognitive function and the PET signals of both 11C-acetate and 18F-FDG. We demonstrate the potential value of PET imaging with 11C-acetate and 18F-FDG by visualizing reactive astrogliosis and the associated neuronal glucose hypometablosim for AD patients. Our findings further suggest that the acetate-boosted reactive astrocyte-neuron interaction could contribute to the cognitive decline in AD.
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Affiliation(s)
- Min-Ho Nam
- Brain Science Institute, Korea Institute of Science and Technology (KIST), Seoul 02792, Republic of Korea
- Department of KHU-KIST Convergence Science and Technology, Kyung Hee University, Seoul 02447, Republic of Korea
| | - Hae Young Ko
- Department of Nuclear Medicine, Severance Hospital, Yonsei University College of Medicine, Seoul 03722, Republic of Korea
| | - Dongwoo Kim
- Department of Nuclear Medicine, Severance Hospital, Yonsei University College of Medicine, Seoul 03722, Republic of Korea
| | - Sangwon Lee
- Department of Nuclear Medicine, Severance Hospital, Yonsei University College of Medicine, Seoul 03722, Republic of Korea
| | - Yongmin Mason Park
- Center for Cognition and Sociality, Institute for Basic Science, Daejeon 34126, Republic of Korea
- IBS School, University of Science and Technology, Daejeon 34126, Republic of Korea
| | - Seung Jae Hyeon
- Brain Science Institute, Korea Institute of Science and Technology (KIST), Seoul 02792, Republic of Korea
| | - Woojin Won
- Center for Cognition and Sociality, Institute for Basic Science, Daejeon 34126, Republic of Korea
| | - Jee-In Chung
- Department of Nuclear Medicine, Severance Hospital, Yonsei University College of Medicine, Seoul 03722, Republic of Korea
| | - Seon Yoo Kim
- Department of Nuclear Medicine, Severance Hospital, Yonsei University College of Medicine, Seoul 03722, Republic of Korea
| | - Han Hee Jo
- Department of Nuclear Medicine, Severance Hospital, Yonsei University College of Medicine, Seoul 03722, Republic of Korea
| | - Kyeong Taek Oh
- Department of Medical Engineering, Yonsei University College of Medicine, Seoul 03722, Republic of Korea
| | - Young-Eun Han
- Brain Science Institute, Korea Institute of Science and Technology (KIST), Seoul 02792, Republic of Korea
| | - Gwan-Ho Lee
- Research Resources Division, KIST, Seoul 02792, Republic of Korea
| | - Yeon Ha Ju
- Brain Science Institute, Korea Institute of Science and Technology (KIST), Seoul 02792, Republic of Korea
- Center for Cognition and Sociality, Institute for Basic Science, Daejeon 34126, Republic of Korea
- IBS School, University of Science and Technology, Daejeon 34126, Republic of Korea
| | - Hyowon Lee
- Brain Science Institute, Korea Institute of Science and Technology (KIST), Seoul 02792, Republic of Korea
| | - Hyunjin Kim
- Brain Science Institute, Korea Institute of Science and Technology (KIST), Seoul 02792, Republic of Korea
- Department of KHU-KIST Convergence Science and Technology, Kyung Hee University, Seoul 02447, Republic of Korea
| | - Jaejun Heo
- Brain Science Institute, Korea Institute of Science and Technology (KIST), Seoul 02792, Republic of Korea
| | - Mridula Bhalla
- Center for Cognition and Sociality, Institute for Basic Science, Daejeon 34126, Republic of Korea
- IBS School, University of Science and Technology, Daejeon 34126, Republic of Korea
| | - Ki Jung Kim
- Center for Cognition and Sociality, Institute for Basic Science, Daejeon 34126, Republic of Korea
| | - Jea Kwon
- Center for Cognition and Sociality, Institute for Basic Science, Daejeon 34126, Republic of Korea
| | - Thor D Stein
- Boston University Alzheimer’s Disease Research Center and Department of Pathology, Chobanian and Avedisian Boston University School of Medicine, Boston, MA 02130, USA
| | - Mingyu Kong
- Molecular Recognition Research Center, KIST, Seoul 02792, Republic of Korea
| | - Hyunbeom Lee
- Molecular Recognition Research Center, KIST, Seoul 02792, Republic of Korea
| | - Seung Eun Lee
- Research Resources Division, KIST, Seoul 02792, Republic of Korea
| | - Soo-Jin Oh
- Brain Science Institute, Korea Institute of Science and Technology (KIST), Seoul 02792, Republic of Korea
| | - Joong-Hyun Chun
- Department of Nuclear Medicine, Severance Hospital, Yonsei University College of Medicine, Seoul 03722, Republic of Korea
| | - Mi-Ae Park
- Department of Radiology, UT Southwestern Medical Center, Dallas, TX 75390, USA
| | - Ki Duk Park
- Brain Science Institute, Korea Institute of Science and Technology (KIST), Seoul 02792, Republic of Korea
| | - Hoon Ryu
- Brain Science Institute, Korea Institute of Science and Technology (KIST), Seoul 02792, Republic of Korea
- Boston University Alzheimer’s Disease Research Center and Department of Pathology, Chobanian and Avedisian Boston University School of Medicine, Boston, MA 02130, USA
| | - Mijin Yun
- Department of Nuclear Medicine, Severance Hospital, Yonsei University College of Medicine, Seoul 03722, Republic of Korea
| | - C Justin Lee
- Center for Cognition and Sociality, Institute for Basic Science, Daejeon 34126, Republic of Korea
- IBS School, University of Science and Technology, Daejeon 34126, Republic of Korea
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8
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Zorec R, Vardjan N. Adrenergic regulation of astroglial aerobic glycolysis and lipid metabolism: Towards a noradrenergic hypothesis of neurodegeneration. Neurobiol Dis 2023; 182:106132. [PMID: 37094775 DOI: 10.1016/j.nbd.2023.106132] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2023] [Revised: 04/18/2023] [Accepted: 04/19/2023] [Indexed: 04/26/2023] Open
Abstract
Ageing is a key factor in the development of cognitive decline and dementia, an increasing and challenging problem of the modern world. The most commonly diagnosed cognitive decline is related to Alzheimer's disease (AD), the pathophysiology of which is poorly understood. Several hypotheses have been proposed. The cholinergic hypothesis is the oldest, however, recently the noradrenergic system has been considered to have a role as well. The aim of this review is to provide evidence that supports the view that an impaired noradrenergic system is causally linked to AD. Although dementia is associated with neurodegeneration and loss of neurons, this likely develops due to a primary failure of homeostatic cells, astrocytes, abundant and heterogeneous neuroglial cells in the central nervous system (CNS). The many functions that astrocytes provide to maintain the viability of neural networks include the control of ionic balance, neurotransmitter turnover, synaptic connectivity and energy balance. This latter function is regulated by noradrenaline, released from the axon varicosities of neurons arising from the locus coeruleus (LC), the primary site of noradrenaline release in the CNS. The demise of the LC is linked to AD, whereby a hypometabolic CNS state is observed clinically. This is likely due to impaired release of noradrenaline in the AD brain during states of arousal, attention and awareness. These functions controlled by the LC are needed for learning and memory formation and require activation of the energy metabolism. In this review, we address first the process of neurodegeneration and cognitive decline, highlighting the function of astrocytes. Cholinergic and/or noradrenergic deficits lead to impaired astroglial function. Then, we focus on adrenergic control of astroglial aerobic glycolysis and lipid droplet metabolism, which play a protective role but also promote neurodegeneration under some circumstances, supporting the noradrenergic hypothesis of cognitive decline. We conclude that targeting astroglial metabolism, glycolysis and/or mitochondrial processes may lead to important new developments in the future when searching for medicines to prevent or even halt cognitive decline.
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Affiliation(s)
- 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.
| | - 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.
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9
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Bhat UA, Kumar SA, Chakravarty S, Patel AB, Kumar A. Differential Effects of Chronic Ethanol Use on Mouse Neuronal and Astroglial Metabolic Activity. Neurochem Res 2023:10.1007/s11064-023-03922-y. [PMID: 37069415 DOI: 10.1007/s11064-023-03922-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2022] [Revised: 03/20/2023] [Accepted: 03/24/2023] [Indexed: 04/19/2023]
Abstract
Chronic alcohol use disorder, a major risk factor for the development of neuropsychiatric disorders including addiction to other substances, is associated with several neuropathology including perturbed neuronal and glial activities in the brain. It affects carbon metabolism in specific brain regions, and perturbs neuro-metabolite homeostasis in neuronal and glial cells. Alcohol induced changes in the brain neurochemical profile accompany the negative emotional state associated with dysregulated reward and sensitized stress response to withdrawal. However, the underlying alterations in neuro-astroglial activities and neurochemical dysregulations in brain regions after chronic alcohol use are poorly understood. This study evaluates the impact of chronic ethanol use on the regional neuro-astroglial metabolic activity using 1H-[13C]-NMR spectroscopy in conjunction with infusion of [1,6-13C2]glucose and sodium [2-13C]acetate, respectively, after 48 h of abstinence. Besides establishing detailed 13C labeling of neuro-metabolites in a brain region-specific manner, our results show chronic ethanol induced-cognitive deficits along with a reduction in total glucose oxidation rates in the hippocampus and striatum. Furthermore, using [2-13C]acetate infusion, we showed an alcohol-induced increase in astroglial metabolic activity in the hippocampus and prefrontal cortex. Interestingly, increased astroglia activity in the hippocampus and prefrontal cortex was associated with a differential expression of monocarboxylic acid transporters that are regulating acetate uptake and metabolism in the brain.
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Affiliation(s)
- Unis Ahmad Bhat
- Epigenetics and Neuropsychiatric Disorders Laboratory, CSIR-Centre for Cellular and Molecular Biology (CCMB), Uppal Road, Habsiguda, Hyderabad, Telangana State (TS), 500007, India
| | - Sreemantula Arun Kumar
- Applied Biology, CSIR-Indian Institute of Chemical Technology, Hyderabad, Telangana, India
| | - Sumana Chakravarty
- Applied Biology, CSIR-Indian Institute of Chemical Technology, Hyderabad, Telangana, India
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, India
| | - Anant Bahadur Patel
- Epigenetics and Neuropsychiatric Disorders Laboratory, CSIR-Centre for Cellular and Molecular Biology (CCMB), Uppal Road, Habsiguda, Hyderabad, Telangana State (TS), 500007, India.
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, India.
- NMR Microimaging and Spectroscopy, CSIR-Centre for Cellular and Molecular Biology (CCMB), Uppal Road, Habsiguda, Hyderabad, Telangana State (TS), 500007, India.
| | - Arvind Kumar
- Epigenetics and Neuropsychiatric Disorders Laboratory, CSIR-Centre for Cellular and Molecular Biology (CCMB), Uppal Road, Habsiguda, Hyderabad, Telangana State (TS), 500007, India.
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, India.
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10
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Metabolic and Cellular Compartments of Acetyl-CoA in the Healthy and Diseased Brain. Int J Mol Sci 2022; 23:ijms231710073. [PMID: 36077475 PMCID: PMC9456256 DOI: 10.3390/ijms231710073] [Citation(s) in RCA: 18] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2022] [Revised: 08/29/2022] [Accepted: 08/31/2022] [Indexed: 11/25/2022] Open
Abstract
The human brain is characterised by the most diverse morphological, metabolic and functional structure among all body tissues. This is due to the existence of diverse neurons secreting various neurotransmitters and mutually modulating their own activity through thousands of pre- and postsynaptic interconnections in each neuron. Astroglial, microglial and oligodendroglial cells and neurons reciprocally regulate the metabolism of key energy substrates, thereby exerting several neuroprotective, neurotoxic and regulatory effects on neuronal viability and neurotransmitter functions. Maintenance of the pool of mitochondrial acetyl-CoA derived from glycolytic glucose metabolism is a key factor for neuronal survival. Thus, acetyl-CoA is regarded as a direct energy precursor through the TCA cycle and respiratory chain, thereby affecting brain cell viability. It is also used for hundreds of acetylation reactions, including N-acetyl aspartate synthesis in neuronal mitochondria, acetylcholine synthesis in cholinergic neurons, as well as divergent acetylations of several proteins, peptides, histones and low-molecular-weight species in all cellular compartments. Therefore, acetyl-CoA should be considered as the central point of metabolism maintaining equilibrium between anabolic and catabolic pathways in the brain. This review presents data supporting this thesis.
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11
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Cuervo-Zanatta D, Syeda T, Sánchez-Valle V, Irene-Fierro M, Torres-Aguilar P, Torres-Ramos MA, Shibayama-Salas M, Silva-Olivares A, Noriega LG, Torres N, Tovar AR, Ruminot I, Barros LF, García-Mena J, Perez-Cruz C. Dietary Fiber Modulates the Release of Gut Bacterial Products Preventing Cognitive Decline in an Alzheimer's Mouse Model. Cell Mol Neurobiol 2022; 43:1595-1618. [PMID: 35953741 DOI: 10.1007/s10571-022-01268-7] [Citation(s) in RCA: 18] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2022] [Accepted: 07/28/2022] [Indexed: 12/11/2022]
Abstract
Fiber intake is associated with a lower risk for Alzheimer´s disease (AD) in older adults. Intake of plant-based diets rich in soluble fiber promotes the production of short-chain fatty acids (SCFAs: butyrate, acetate, propionate) by gut bacteria. Butyrate administration has antiinflammatory actions, but propionate promotes neuroinflammation. In AD patients, gut microbiota dysbiosis is a common feature even in the prodromal stages of the disease. It is unclear whether the neuroprotective effects of fiber intake rely on gut microbiota modifications and specific actions of SCFAs in brain cells. Here, we show that restoration of the gut microbiota dysbiosis through the intake of soluble fiber resulted in lower propionate and higher butyrate production, reduced astrocyte activation and improved cognitive function in 6-month-old male APP/PS1 mice. The neuroprotective effects were lost in antibiotic-treated mice. Moreover, propionate promoted higher glycolysis and mitochondrial respiration in astrocytes, while butyrate induced a more quiescent metabolism. Therefore, fiber intake neuroprotective action depends on the modulation of butyrate/propionate production by gut bacteria. Our data further support and provide a mechanism to explain the beneficial effects of dietary interventions rich in soluble fiber to prevent dementia and AD. Fiber intake restored the concentration of propionate and butyrate by modulating the composition of gut microbiota in male transgenic (Tg) mice with Alzheimer´s disease. Gut dysbiosis was associated with intestinal damage and high propionate levels in control diet fed-Tg mice. Fiber-rich diet restored intestinal integrity and promoted the abundance of butyrate-producing bacteria. Butyrate concentration was associated with better cognitive performance in fiber-fed Tg mice. A fiber-rich diet may prevent the development of a dysbiotic microbiome and the related cognitive dysfunction in people at risk of developing Alzheimer´s disease.
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Affiliation(s)
- Daniel Cuervo-Zanatta
- Laboratorio de Neuroplasticidad y Neurodegeneración, Departamento de Farmacologia, Centro de Investigación y de Estudios Avanzados del I.P.N. (Cinvestav), Av. IPN 2508, Ciudad de Mexico, 07360, México.,Laboratorio de Referencia y Soporte Para Genomas, Transcriptomas y Caracterización de Microbiomas, Departamento de Genética y Biología Molecular, Centro de Investigación y de Estudios Avanzados del I.P.N. (Cinvestav), Av. IPN 2508, Ciudad de Mexico, 07360, México
| | - Tauqeerunnisa Syeda
- Laboratorio de Neuroplasticidad y Neurodegeneración, Departamento de Farmacologia, Centro de Investigación y de Estudios Avanzados del I.P.N. (Cinvestav), Av. IPN 2508, Ciudad de Mexico, 07360, México
| | - Vicente Sánchez-Valle
- Laboratorio de Neuroplasticidad y Neurodegeneración, Departamento de Farmacologia, Centro de Investigación y de Estudios Avanzados del I.P.N. (Cinvestav), Av. IPN 2508, Ciudad de Mexico, 07360, México
| | - Mariangel Irene-Fierro
- Laboratorio de Neuroplasticidad y Neurodegeneración, Departamento de Farmacologia, Centro de Investigación y de Estudios Avanzados del I.P.N. (Cinvestav), Av. IPN 2508, Ciudad de Mexico, 07360, México
| | - Pablo Torres-Aguilar
- Unidad Periférica de Neurociencias, Instituto de Neurología y Neurocirugía Manuel Velasco Suárez (INNNMVS), Ciudad de Mexico, 14269, México
| | - Mónica Adriana Torres-Ramos
- Unidad Periférica de Neurociencias, Instituto de Neurología y Neurocirugía Manuel Velasco Suárez (INNNMVS), Ciudad de Mexico, 14269, México
| | - Mineko Shibayama-Salas
- Departmento de Infectómica y Patogénesis Molecular, Centro de Investigación y de Estudios Avanzados del I.P.N. (Cinvestav), Av. IPN 2508, 07360, Ciudad de Mexico, Mexico
| | - Angélica Silva-Olivares
- Departmento de Infectómica y Patogénesis Molecular, Centro de Investigación y de Estudios Avanzados del I.P.N. (Cinvestav), Av. IPN 2508, 07360, Ciudad de Mexico, Mexico
| | - Lilia G Noriega
- Departamento de Fisiología de la Nutrición, Instituto Nacional de Ciencias Médicas y de la Nutrición "Salvador Zubiran" (INCMNSZ), 14080, Ciudad de México, Mexico
| | - Nimbe Torres
- Departamento de Fisiología de la Nutrición, Instituto Nacional de Ciencias Médicas y de la Nutrición "Salvador Zubiran" (INCMNSZ), 14080, Ciudad de México, Mexico
| | - Armando R Tovar
- Departamento de Fisiología de la Nutrición, Instituto Nacional de Ciencias Médicas y de la Nutrición "Salvador Zubiran" (INCMNSZ), 14080, Ciudad de México, Mexico
| | - Iván Ruminot
- Universidad San Sebastián, Facultad de Medicina y Ciencia, Centro de Estudios Científicos-CECs, Valdivia, Chile
| | - L Felipe Barros
- Universidad San Sebastián, Facultad de Medicina y Ciencia, Centro de Estudios Científicos-CECs, Valdivia, Chile
| | - Jaime García-Mena
- Laboratorio de Referencia y Soporte Para Genomas, Transcriptomas y Caracterización de Microbiomas, Departamento de Genética y Biología Molecular, Centro de Investigación y de Estudios Avanzados del I.P.N. (Cinvestav), Av. IPN 2508, Ciudad de Mexico, 07360, México.
| | - Claudia Perez-Cruz
- Laboratorio de Neuroplasticidad y Neurodegeneración, Departamento de Farmacologia, Centro de Investigación y de Estudios Avanzados del I.P.N. (Cinvestav), Av. IPN 2508, Ciudad de Mexico, 07360, México.
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12
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Roy D, Puvvada M, Kapanaiah SKT, Patel AB. Enhanced Cortical Metabolic Activity in Females and Males of a Slow Progressing Mouse Model of Amyotrophic Lateral Sclerosis. Neurochem Res 2022; 47:1765-1777. [PMID: 35347633 DOI: 10.1007/s11064-022-03568-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2021] [Revised: 02/23/2022] [Accepted: 02/28/2022] [Indexed: 10/18/2022]
Abstract
Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disorder with selective degeneration of motor neurons in the central nervous system. The pathophysiology of ALS is not well understood. We have used 1H-[13C]-NMR spectroscopy together with an administration of [1,6-13C2]glucose and [2-13C]acetate in female and male SOD1G37R mice to assess neuronal and astroglial metabolic activity, respectively, in the central nervous system in ALS condition. The female (p = 0.0008) and male (p < 0.0001) SOD1G37R mice exhibited decreased forelimb strength when compared with wild-type mice. There was a reduction in N-acetylaspartylglutamate level, and elevation in myo-inositol in the spinal cord of female and male SOD1G37R mice. The transgenic male mice exhibited increased acetate oxidation in the spinal cord (p = 0.05) and cerebral cortex (p = 0.03), while females showed an increase in the spinal cord (p = 0.02) only. As acetate is transported and preferentially metabolized in the astrocytes, the finding of increased rate of acetate oxidation in the transgenic mice is suggestive of astrocytic involvement in the pathogenesis of ALS. The rates of glucose oxidation in glutamatergic (p = 0.0004) and GABAergic neurons (p = 0.0052) were increased in the cerebral cortex of male SOD1G37R mice when compared with the controls. The female mice showed an increase in glutamatergic (p = 0.039) neurometabolic activity only. The neurometabolic activity was unperturbed in the spinal cord of either sex. These data suggest differential changes in neurometabolic activity across the central nervous system in SOD1G37R mice.
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Affiliation(s)
- Dipak Roy
- NMR Microimaging and Spectroscopy, CSIR-Centre for Cellular and Molecular Biology, Habsiguda, Uppal Road, Hyderabad, 500007, India
| | - Madhuri Puvvada
- NMR Microimaging and Spectroscopy, CSIR-Centre for Cellular and Molecular Biology, Habsiguda, Uppal Road, Hyderabad, 500007, India
| | - Sampath K T Kapanaiah
- NMR Microimaging and Spectroscopy, CSIR-Centre for Cellular and Molecular Biology, Habsiguda, Uppal Road, Hyderabad, 500007, India
| | - Anant Bahadur Patel
- NMR Microimaging and Spectroscopy, CSIR-Centre for Cellular and Molecular Biology, Habsiguda, Uppal Road, Hyderabad, 500007, India. .,Academy of Scientific and Innovative Research, Ghaziabad, 201002, India.
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13
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Liu Y, Jiang H, Qin X, Tian M, Zhang H. PET imaging of reactive astrocytes in neurological disorders. Eur J Nucl Med Mol Imaging 2021; 49:1275-1287. [PMID: 34873637 PMCID: PMC8921128 DOI: 10.1007/s00259-021-05640-5] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2021] [Accepted: 11/24/2021] [Indexed: 12/17/2022]
Abstract
The reactive astrocytes manifest molecular, structural, and functional remodeling in injury, infection, or diseases of the CNS, which play a critical role in the pathological mechanism of neurological diseases. A growing need exists for dependable approach to better characterize the activation of astrocyte in vivo. As an advanced molecular imaging technology, positron emission tomography (PET) has the potential for visualizing biological activities at the cellular levels. In the review, we summarized the PET visualization strategies for reactive astrocytes and discussed the applications of astrocyte PET imaging in neurological diseases. Future studies are needed to pay more attention to the development of specific imaging agents for astrocytes and further improve our exploration of reactive astrocytes in various diseases.
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Affiliation(s)
- Yu Liu
- Department of Nuclear Medicine and PET Center, The Second Affiliated Hospital of Zhejiang University School of Medicine, 88 Jiefang Road, Hangzhou, 310009, Zhejiang, China.,Institute of Nuclear Medicine and Molecular Imaging of Zhejiang University, Hangzhou, China.,Key Laboratory of Medical Molecular Imaging of Zhejiang Province, Hangzhou, China
| | - Han Jiang
- PET-CT Center, Fujian Medical University Union Hospital, Fuzhou, 350001, China
| | - Xiyi Qin
- Department of Nuclear Medicine and PET Center, The Second Affiliated Hospital of Zhejiang University School of Medicine, 88 Jiefang Road, Hangzhou, 310009, Zhejiang, China.,Institute of Nuclear Medicine and Molecular Imaging of Zhejiang University, Hangzhou, China.,Key Laboratory of Medical Molecular Imaging of Zhejiang Province, Hangzhou, China
| | - Mei Tian
- Department of Nuclear Medicine and PET Center, The Second Affiliated Hospital of Zhejiang University School of Medicine, 88 Jiefang Road, Hangzhou, 310009, Zhejiang, China. .,Institute of Nuclear Medicine and Molecular Imaging of Zhejiang University, Hangzhou, China. .,Key Laboratory of Medical Molecular Imaging of Zhejiang Province, Hangzhou, China.
| | - Hong Zhang
- Department of Nuclear Medicine and PET Center, The Second Affiliated Hospital of Zhejiang University School of Medicine, 88 Jiefang Road, Hangzhou, 310009, Zhejiang, China. .,Institute of Nuclear Medicine and Molecular Imaging of Zhejiang University, Hangzhou, China. .,Key Laboratory of Medical Molecular Imaging of Zhejiang Province, Hangzhou, China. .,College of Biomedical Engineering & Instrument Science, Zhejiang University, Hangzhou, China. .,Key Laboratory for Biomedical Engineering of Ministry of Education, Zhejiang University, Hangzhou, China.
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14
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Positron emission tomography in multiple sclerosis - straight to the target. Nat Rev Neurol 2021; 17:663-675. [PMID: 34545219 DOI: 10.1038/s41582-021-00537-1] [Citation(s) in RCA: 26] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/30/2021] [Indexed: 02/08/2023]
Abstract
Following the impressive progress in the treatment of relapsing-remitting multiple sclerosis (MS), the major challenge ahead is the development of treatments to prevent or delay the irreversible accumulation of clinical disability in progressive forms of the disease. The substrate of clinical progression is neuro-axonal degeneration, and a deep understanding of the mechanisms that underlie this process is a precondition for the development of therapies for progressive MS. PET imaging involves the use of radiolabelled compounds that bind to specific cellular and metabolic targets, thereby enabling direct in vivo measurement of several pathological processes. This approach can provide key insights into the clinical relevance of these processes and their chronological sequence during the disease course. In this Review, we focus on the contribution that PET is making to our understanding of extraneuronal and intraneuronal mechanisms that are involved in the pathogenesis of irreversible neuro-axonal damage in MS. We consider the major challenges with the use of PET in MS and the steps necessary to realize clinical benefits of the technique. In addition, we discuss the potential of emerging PET tracers and future applications of existing compounds to facilitate the identification of effective neuroprotective treatments for patients with MS.
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15
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Inhibition of Glutamate Release, but Not of Glutamine Recycling to Glutamate, Is Involved in Delaying the Onset of Initial Lithium-Pilocarpine-Induced Seizures in Young Rats by a Non-Convulsive MSO Dose. Int J Mol Sci 2021; 22:ijms222011127. [PMID: 34681786 PMCID: PMC8536987 DOI: 10.3390/ijms222011127] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2021] [Revised: 10/08/2021] [Accepted: 10/12/2021] [Indexed: 12/12/2022] Open
Abstract
Initial seizures observed in young rats during the 60 min after administration of pilocarpine (Pilo) were delayed and attenuated by pretreatment with a non-convulsive dose of methionine sulfoximine (MSO). We hypothesized that the effect of MSO results from a) glutamine synthetase block-mediated inhibition of conversion of Glu/Gln precursors to neurotransmitter Glu, and/or from b) altered synaptic Glu release. Pilo was administered 60 min prior to sacrifice, MSO at 75 mg/kg, i.p., 2.5 h earlier. [1,2-13C]acetate and [U-13C]glucose were i.p.-injected either together with Pilo (short period) or 15 min before sacrifice (long period). Their conversion to Glu and Gln in the hippocampus and entorhinal cortex was followed using [13C] gas chromatography-mass spectrometry. Release of in vitro loaded Glu surrogate, [3H]d-Asp from ex vivo brain slices was monitored in continuously collected superfusates. [3H]d-Asp uptake was tested in freshly isolated brain slices. At no time point nor brain region did MSO modify incorporation of [13C] to Glu or Gln in Pilo-treated rats. MSO pretreatment decreased by ~37% high potassium-induced [3H]d-Asp release, but did not affect [3H]d-Asp uptake. The results indicate that MSO at a non-convulsive dose delays the initial Pilo-induced seizures by interfering with synaptic Glu-release but not with neurotransmitter Glu recycling.
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16
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Soni ND, Ramesh A, Roy D, Patel AB. Brain energy metabolism in intracerebroventricularly administered streptozotocin mouse model of Alzheimer's disease: A 1H-[ 13C]-NMR study. J Cereb Blood Flow Metab 2021; 41:2344-2355. [PMID: 33657898 PMCID: PMC8393290 DOI: 10.1177/0271678x21996176] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Alzheimer's disease (AD) is a very common neurodegenerative disorder. Although a majority of the AD cases are sporadic, most of the studies are conducted using transgenic models. Intracerebroventricular (ICV) administered streptozotocin (STZ) animals have been used to explore mechanisms in sporadic AD. In this study, we have investigated memory and neurometabolism of ICV-STZ-administered C57BL6/J mice. The neuronal and astroglial metabolic activity was measured in 1H-[13C]-NMR spectrum of cortical and hippocampal tissue extracts of mice infused with [1,6-13C2]glucose and [2-13C]acetate, respectively. STZ-administered mice exhibited reduced (p = 0.00002) recognition index for memory. The levels of creatine, GABA, glutamate and NAA were reduced (p ≤ 0.04), while that of myo-inositol was increased (p < 0.05) in STZ-treated mice. There was a significant (p ≤ 0.014) reduction in aspartate-C3, glutamate-C4/C3, GABA-C2 and glutamine-C4 labeling from [1,6-13C2]glucose. This resulted in decreased rate of glucose oxidation in the cerebral cortex (0.64 ± 0.05 vs. 0.77 ± 0.05 µmol/g/min, p = 0.0008) and hippocampus (0.60 ± 0.04 vs. 0.73 ± 0.07 µmol/g/min, p = 0.001) of STZ-treated mice, due to similar reductions of glucose oxidation in glutamatergic and GABAergic neurons. Additionally, reduced glutamine-C4 labeling points towards compromised synaptic neurotransmission in STZ-treated mice. These data suggest that the ICV-STZ model exhibits neurometabolic deficits typically observed in AD, and its utility in understanding the mechanism of sporadic AD.
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Affiliation(s)
- Narayan D Soni
- NMR Microimaging and Spectroscopy, CSIR-Centre for Cellular and Molecular Biology, Hyderabad, India
| | - Akila Ramesh
- NMR Microimaging and Spectroscopy, CSIR-Centre for Cellular and Molecular Biology, Hyderabad, India
| | - Dipak Roy
- NMR Microimaging and Spectroscopy, CSIR-Centre for Cellular and Molecular Biology, Hyderabad, India
| | - Anant B Patel
- NMR Microimaging and Spectroscopy, CSIR-Centre for Cellular and Molecular Biology, Hyderabad, India.,Academy of Scientific and Innovative Research, Ghaziabad, India
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17
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Galkina OV, Vetrovoy OV, Eschenko ND. The Role of Lipids in Implementing Specific Functions in the Central Nervous System. RUSSIAN JOURNAL OF BIOORGANIC CHEMISTRY 2021. [DOI: 10.1134/s1068162021050253] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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18
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Anbalagan S. Endocrine cross-talk between the gut microbiome and glial cells in development and disease. J Neuroendocrinol 2021; 33:e12924. [PMID: 34019340 DOI: 10.1111/jne.12924] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/03/2020] [Revised: 11/20/2020] [Accepted: 11/20/2020] [Indexed: 11/27/2022]
Abstract
Glial cells make up the major cellular component of the nervous system. Glial development is usually investigated through perturbations of host genetics, although non-host-derived signalling molecules can also regulate glial cells. Indeed, gut microbiome colonisation and the presence of microbiome-derived factors in the blood coincide with glial cell development. Emerging data suggest that the gut microbiome can regulate gliogenesis, myelination and glial epigenetics. Neurodegenerative diseases are characterised by changes in the gut microbiome and glial dysfunction. This perspective discusses the ways in which microbiome-derived molecules can engage in cross-talk with glial cells during development and in dysfunctional glial diseases.
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Affiliation(s)
- Savani Anbalagan
- ReMedy International Research Agenda Programme, Centre of New Technologies, University of Warsaw, Warsaw, Poland
- Institute of Molecular Biology and Biotechnology, Faculty of Biology, Adam Mickiewicz University in Poznań, Poznań, Poland
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19
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Tanabe J, Neff S, Sutton B, Ellis S, Patten L, Brown MS, Hoffman PL, Tabakoff B, Burnham EL. Effects of acetate on cerebral blood flow, systemic inflammation, and behavior in alcohol use disorder. Alcohol Clin Exp Res 2021; 45:922-933. [PMID: 33682145 PMCID: PMC8496991 DOI: 10.1111/acer.14588] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2020] [Revised: 02/19/2021] [Accepted: 02/22/2021] [Indexed: 11/30/2022]
Abstract
BACKGROUND Alcohol use disorders (AUDs) are associated with altered regulation of physiological processes in the brain. Acetate, a metabolite of ethanol, has been implicated in several processes that are disrupted in AUDs including transcriptional regulation, metabolism, inflammation, and neurotransmission. To further understand the effects of acetate on brain function in AUDs, we investigated the effects of acetate on cerebral blood flow (CBF), systemic inflammatory cytokines, and behavior in AUD. METHODS Sixteen participants with AUD were recruited from a nonmedical, clinically managed detoxification center. Each participant received acetate and placebo in a randomly assigned order of infusion and underwent 3T MR scanning using quantitative pseudo-continuous arterial spin labeling. Participants and the study team were blinded to the infusion. CBF values (ml/100 g/min) extracted from thalamus were compared between placebo and acetate using a mixed effect linear regression model accounting for infusion order. Voxel-wise CBF comparisons were set at threshold of p < 0.05 cluster-corrected for multiple comparisons, voxel-level p < 0.0001. Plasma cytokine levels and behavior were also assessed between infusions. RESULTS Fifteen men and 1 woman were enrolled with Alcohol Use Disorders Identification Test (AUDIT) scores between 13 and 38 with a mean of 28.3 ± 9.1. Compared to placebo, acetate administration increased CBF in the thalamus bilaterally (Left: 51.2 vs. 68.8, p < 0.001; Right: 53.7 vs. 69.6, p = 0.001), as well as the cerebellum, brainstem, and cortex. Older age and higher AUDIT scores were associated with increases in acetate-induced thalamic blood flow. Cytokine levels and behavioral measures did not differ between placebo and acetate infusions. CONCLUSIONS This pilot study in AUD suggests that during the first week of abstinence from alcohol, the brain's response to acetate differs by brain region and this response may be associated with the severity of alcohol dependence.
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Affiliation(s)
- Jody Tanabe
- Department of Radiology, School of Medicine, University of Colorado Anschutz Medical Campus, Aurora, CO, 80045
- Department of Psychiatry, School of Medicine, University of Colorado Anschutz Medical Campus, Aurora, CO, 80045
| | - Sarah Neff
- Department of Medicine, School of Medicine, University of Colorado Anschutz Medical Campus, Aurora, CO, 80045
| | - Brianne Sutton
- Department of Psychiatry, School of Medicine, University of Colorado Anschutz Medical Campus, Aurora, CO, 80045
| | - Sam Ellis
- Department of Pharmaceutical Sciences, School of Pharmacy, University of Colorado Anschutz Medical Campus, Aurora, CO, 80045
| | - Luke Patten
- Department of Biostatistics and Informatics, School of Public Health; University of Colorado Anschutz Medical Campus, Aurora, CO, 80045
| | - Mark S. Brown
- Department of Radiology, School of Medicine, University of Colorado Anschutz Medical Campus, Aurora, CO, 80045
| | - Paula L. Hoffman
- Department of Pharmacology, School of Medicine, University of Colorado Anschutz Medical Campus, Aurora, CO, 80045
| | - Boris Tabakoff
- Department of Pharmaceutical Sciences, School of Pharmacy, University of Colorado Anschutz Medical Campus, Aurora, CO, 80045
| | - Ellen L. Burnham
- Department of Medicine, School of Medicine, University of Colorado Anschutz Medical Campus, Aurora, CO, 80045
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20
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Lotun A, Gessler DJ, Gao G. Canavan Disease as a Model for Gene Therapy-Mediated Myelin Repair. Front Cell Neurosci 2021; 15:661928. [PMID: 33967698 PMCID: PMC8102781 DOI: 10.3389/fncel.2021.661928] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2021] [Accepted: 03/23/2021] [Indexed: 11/13/2022] Open
Abstract
In recent years, the scientific and therapeutic fields for rare, genetic central nervous system (CNS) diseases such as leukodystrophies, or white matter disorders, have expanded significantly in part due to technological advancements in cellular and clinical screenings as well as remedial therapies using novel techniques such as gene therapy. However, treatments aimed at normalizing the pathological changes associated with leukodystrophies have especially been complicated due to the innate and variable effects of glial abnormalities, which can cause large-scale functional deficits in developmental myelination and thus lead to downstream neuronal impairment. Emerging research in the past two decades have depicted glial cells, particularly oligodendrocytes and astrocytes, as key, regulatory modulators in constructing and maintaining myelin function and neuronal viability. Given the significance of myelin formation in the developing brain, myelin repair in a time-dependent fashion is critical in restoring homeostatic functionality to the CNS of patients diagnosed with white matter disorders. Using Canavan Disease (CD) as a leukodystrophy model, here we review the hypothetical roles of N-acetylaspartate (NAA), one of the brain's most abundant amino acid derivatives, in Canavan disease's CNS myelinating pathology, as well as discuss the possible functions astrocytes serve in both CD and other leukodystrophies' time-sensitive disease correction. Through this analysis, we also highlight the potential remyelinating benefits of gene therapy for other leukodystrophies in which alternative CNS cell targeting for white matter disorders may be an applicable path for reparative treatment.
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Affiliation(s)
- Anoushka Lotun
- Horae Gene Therapy Center, University of Massachusetts Medical School, Worcester, MA, United States.,Department of Microbiology and Physiological Systems, University of Massachusetts Medical School, Worcester, MA, United States
| | - Dominic J Gessler
- Horae Gene Therapy Center, University of Massachusetts Medical School, Worcester, MA, United States.,Department of Microbiology and Physiological Systems, University of Massachusetts Medical School, Worcester, MA, United States.,Department of Neurosurgery, University of Minnesota, Minneapolis, MN, United States
| | - Guangping Gao
- Horae Gene Therapy Center, University of Massachusetts Medical School, Worcester, MA, United States.,Department of Microbiology and Physiological Systems, University of Massachusetts Medical School, Worcester, MA, United States.,Li Weibo Institute for Rare Diseases Research, University of Massachusetts Medical School, Worcester, MA, United States
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21
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Gasmi A, Peana M, Arshad M, Butnariu M, Menzel A, Bjørklund G. Krebs cycle: activators, inhibitors and their roles in the modulation of carcinogenesis. Arch Toxicol 2021; 95:1161-1178. [DOI: 10.1007/s00204-021-02974-9] [Citation(s) in RCA: 33] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2020] [Accepted: 01/04/2021] [Indexed: 12/12/2022]
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22
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Effects of ketogenic diet and ketone monoester supplement on acute alcohol withdrawal symptoms in male mice. Psychopharmacology (Berl) 2021; 238:833-844. [PMID: 33410985 PMCID: PMC7914216 DOI: 10.1007/s00213-020-05735-1] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/24/2020] [Accepted: 11/24/2020] [Indexed: 12/25/2022]
Abstract
RATIONALE After alcohol ingestion, the brain partly switches from consumption of glucose to consumption of the alcohol metabolite acetate. In heavy drinkers, the switch persists after abrupt abstinence, leading to the hypothesis that the resting brain may be "starved" when acetate levels suddenly drop during abstinence, despite normal blood glucose, contributing to withdrawal symptoms. We hypothesized that ketone bodies, like acetate, could act as alternative fuels in the brain and alleviate withdrawal symptoms. OBJECTIVES We previously reported that a ketogenic diet during alcohol exposure reduced acute withdrawal symptoms in rats. Here, our goals were to test whether (1) we could reproduce our findings, in mice and with longer alcohol exposure; (2) ketone bodies alone are sufficient to reduce withdrawal symptoms (clarifying mechanism); (3) introduction of ketogenic diets at abstinence (a clinically more practical implementation) would also be effective. METHODS Male C57BL/6NTac mice had intermittent alcohol exposure for 3 weeks using liquid diet. Somatic alcohol withdrawal symptoms were measured as handling-induced convulsions; anxiety-like behavior was measured using the light-dark transition test. We tested a ketogenic diet, and a ketone monoester supplement with a regular carbohydrate-containing diet. RESULTS The regular diet with ketone monoester was sufficient to reduce handling-induced convulsions and anxiety-like behaviors in early withdrawal. Only the ketone monoester reduced handling-induced convulsions when given during abstinence, consistent with faster elevation of blood ketones, relative to ketogenic diet. CONCLUSIONS These findings support the potential utility of therapeutic ketosis as an adjunctive treatment in early detoxification in alcohol-dependent patients seeking to become abstinent. TRIAL REGISTRATION clinicaltrials.gov NCT03878225, NCT03255031.
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23
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Kato H, Okuno T, Isohashi K, Koda T, Shimizu M, Mochizuki H, Nakatsuji Y, Hatazawa J. Astrocyte metabolism in multiple sclerosis investigated by 1-C-11 acetate PET. J Cereb Blood Flow Metab 2021; 41:369-379. [PMID: 32169013 PMCID: PMC7812519 DOI: 10.1177/0271678x20911469] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
This study was aimed at evaluating the metabolism of reactive astrocytes in the brains of patients with multiple sclerosis by quantitative 1-C-11 acetate positron emission tomography (PET). Magnetic resonance imaging and 1-C-11 quantitative PET were performed in eight patients with multiple sclerosis and 10 normal control subjects. The efflux rate (k2) of 1-C-11 acetate, which reportedly reflects the metabolic rate of 1-C-11 acetate, was calculated based on the one-tissue compartmental model. Fractional anisotropy was also determined to evaluate the integrity of the neuronal tracts. The values of k2 in the patients with multiple sclerosis were significantly higher than those in the normal control subjects, in both the white matter (p = 0.003) and the gray matter (p = 0.02). In addition, the white matter/gray matter ratio of k2 was significantly higher in the multiple sclerosis patients than in the normal control subjects (p = 0.02). Voxel-based statistical analysis revealed most prominent increase in k2 in the neuronal fiber tracts, as well as decrease in fractional anisotropy in them in the multiple sclerosis patients. The present study clarified that the pathological changes associated with astrocytic reactivation in multiple sclerosis patients could be visualized by quantitative 1-C-11 acetate PET.
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Affiliation(s)
- Hiroki Kato
- Department of Nuclear Medicine and Tracer Kinetics, Osaka University Graduate School of Medicine, Osaka, Japan
| | - Tatsusada Okuno
- Department of Neurology, Osaka University Graduate School of Medicine, Osaka, Japan
| | - Kayako Isohashi
- Department of Nuclear Medicine and Tracer Kinetics, Osaka University Graduate School of Medicine, Osaka, Japan
| | - Toru Koda
- Department of Medical Innovation, Osaka University Hospital Department of Neurology, Osaka University Graduate School of Medicine, Osaka, Japan
| | - Mikito Shimizu
- Department of Neurology, Osaka University Graduate School of Medicine, Osaka, Japan
| | - Hideki Mochizuki
- Department of Neurology, Osaka University Graduate School of Medicine, Osaka, Japan
| | - Yuji Nakatsuji
- Department of Neurology, Toyama University Hospital, Toyama, Japan
| | - Jun Hatazawa
- Department of Nuclear Medicine and Tracer Kinetics, Osaka University Graduate School of Medicine, Osaka, Japan
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24
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Shaidullov I, Ermakova E, Gaifullina A, Mosshammer A, Yakovlev A, Weiger TM, Hermann A, Sitdikova G. Alcohol metabolite acetic acid activates BK channels in a pH-dependent manner and decreases calcium oscillations and exocytosis of secretory granules in rat pituitary GH3 cells. Pflugers Arch 2021; 473:67-77. [PMID: 33113008 DOI: 10.1007/s00424-020-02484-0] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2020] [Revised: 10/16/2020] [Accepted: 10/20/2020] [Indexed: 12/11/2022]
Abstract
Acetaldehyde and acetic acid/acetate, the active metabolites of alcohol (ethanol, EtOH), generate actions of their own ranging from behavioral, physiological, to pathological/cancerogenic effects. EtOH and acetaldehyde have been studied to some depth, whereas the effects of acetic acid have been less well explored. In this study, we investigated the effect of acetic acid on big conductance calcium-activated potassium (BK) channels present in GH3 rat pituitary tumor cells in more detail. In whole cell voltage clamp recordings, extracellular application of acetic acid increased total outward currents in a dose-dependent manner. This effect was prevented after the application of the specific BK channel blocker paxilline. Acetic acid action was pH-dependent-in whole cell current and single BK channel recordings, open probability (Po) was significantly increased by extracellular pH reduction and decreased by neutral or base pH. Acetic acid hyperpolarized the membrane potential, whereas acidic physiological solution had a depolarizing effect. Moreover, acetic acid reduced calcium (Ca2+) oscillations and exocytosis of growth hormone contained secretory granules from GH3 cells. These effects were partially prevented by BK inhibitors-tetraethylammonium or paxillin. In conclusion, our experiments indicate that acetic acid activates BK channels in GH3 cells which eventually contribute to acetic acid-induced membrane hyperpolarization, cessation of Ca2+ oscillations, and decrease of growth hormone release.
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Affiliation(s)
- Ilnar Shaidullov
- Department of Human and Animal Physiology, Institute of Fundamental Medicine and Biology, Kazan Federal University, Kremlevskaya str. 18, Kazan, 420008, Russia
| | - Elizaveta Ermakova
- Department of Human and Animal Physiology, Institute of Fundamental Medicine and Biology, Kazan Federal University, Kremlevskaya str. 18, Kazan, 420008, Russia
| | | | - Anna Mosshammer
- Department of Neurophysiology and Neuropharmacology, Center of Physiology and Pharmacology, Medical University of Vienna, Vienna, Austria
| | - Aleksey Yakovlev
- Department of Human and Animal Physiology, Institute of Fundamental Medicine and Biology, Kazan Federal University, Kremlevskaya str. 18, Kazan, 420008, Russia
| | - Thomas M Weiger
- Department of Biosciences, University of Salzburg, Salzburg, Austria
| | - Anton Hermann
- Department of Biosciences, University of Salzburg, Salzburg, Austria
| | - Guzel Sitdikova
- Department of Human and Animal Physiology, Institute of Fundamental Medicine and Biology, Kazan Federal University, Kremlevskaya str. 18, Kazan, 420008, Russia.
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25
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Moffett JR, Puthillathu N, Vengilote R, Jaworski DM, Namboodiri AM. Acetate Revisited: A Key Biomolecule at the Nexus of Metabolism, Epigenetics and Oncogenesis-Part 1: Acetyl-CoA, Acetogenesis and Acyl-CoA Short-Chain Synthetases. Front Physiol 2020; 11:580167. [PMID: 33281616 PMCID: PMC7689297 DOI: 10.3389/fphys.2020.580167] [Citation(s) in RCA: 57] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2020] [Accepted: 09/23/2020] [Indexed: 12/19/2022] Open
Abstract
Acetate is a major end product of bacterial fermentation of fiber in the gut. Acetate, whether derived from the diet or from fermentation in the colon, has been implicated in a range of health benefits. Acetate is also generated in and released from various tissues including the intestine and liver, and is generated within all cells by deacetylation reactions. To be utilized, all acetate, regardless of the source, must be converted to acetyl coenzyme A (acetyl-CoA), which is carried out by enzymes known as acyl-CoA short-chain synthetases. Acyl-CoA short-chain synthetase-2 (ACSS2) is present in the cytosol and nuclei of many cell types, whereas ACSS1 is mitochondrial, with greatest expression in heart, skeletal muscle, and brown adipose tissue. In addition to acting to redistribute carbon systemically like a ketone body, acetate is becoming recognized as a cellular regulatory molecule with diverse functions beyond the formation of acetyl-CoA for energy derivation and lipogenesis. Acetate acts, in part, as a metabolic sensor linking nutrient balance and cellular stress responses with gene transcription and the regulation of protein function. ACSS2 is an important task-switching component of this sensory system wherein nutrient deprivation, hypoxia and other stressors shift ACSS2 from a lipogenic role in the cytoplasm to a regulatory role in the cell nucleus. Protein acetylation is a critical post-translational modification involved in regulating cell behavior, and alterations in protein acetylation status have been linked to multiple disease states, including cancer. Improving our fundamental understanding of the "acetylome" and how acetate is generated and utilized at the subcellular level in different cell types will provide much needed insight into normal and neoplastic cellular metabolism and the epigenetic regulation of phenotypic expression under different physiological stressors. This article is Part 1 of 2 - for Part 2 see doi: 10.3389/fphys.2020.580171.
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Affiliation(s)
- John R Moffett
- Department of Anatomy, Physiology and Genetics, and Neuroscience Program, Uniformed Services University of the Health Sciences, Bethesda, MD, United States
| | - Narayanan Puthillathu
- Department of Anatomy, Physiology and Genetics, and Neuroscience Program, Uniformed Services University of the Health Sciences, Bethesda, MD, United States
| | - Ranjini Vengilote
- Department of Anatomy, Physiology and Genetics, and Neuroscience Program, Uniformed Services University of the Health Sciences, Bethesda, MD, United States
| | - Diane M Jaworski
- Department of Neurological Sciences, University of Vermont College of Medicine, Burlington, VT, United States
| | - Aryan M Namboodiri
- Department of Anatomy, Physiology and Genetics, and Neuroscience Program, Uniformed Services University of the Health Sciences, Bethesda, MD, United States
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26
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Moffett JR, Puthillathu N, Vengilote R, Jaworski DM, Namboodiri AM. Acetate Revisited: A Key Biomolecule at the Nexus of Metabolism, Epigenetics, and Oncogenesis - Part 2: Acetate and ACSS2 in Health and Disease. Front Physiol 2020; 11:580171. [PMID: 33304273 PMCID: PMC7693462 DOI: 10.3389/fphys.2020.580171] [Citation(s) in RCA: 35] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2020] [Accepted: 10/19/2020] [Indexed: 12/19/2022] Open
Abstract
Acetate, the shortest chain fatty acid, has been implicated in providing health benefits whether it is derived from the diet or is generated from microbial fermentation of fiber in the gut. These health benefits range widely from improved cardiac function to enhanced red blood cell generation and memory formation. Understanding how acetate could influence so many disparate biological functions is now an area of intensive research. Protein acetylation is one of the most common post-translational modifications and increased systemic acetate strongly drives protein acetylation. By virtue of acetylation impacting the activity of virtually every class of protein, acetate driven alterations in signaling and gene transcription have been associated with several common human diseases, including cancer. In part 2 of this review, we will focus on some of the roles that acetate plays in health and human disease. The acetate-activating enzyme acyl-CoA short-chain synthetase family member 2 (ACSS2) will be a major part of that focus due to its role in targeted protein acetylation reactions that can regulate central metabolism and stress responses. ACSS2 is the only known enzyme that can recycle acetate derived from deacetylation reactions in the cytoplasm and nucleus of cells, including both protein and metabolite deacetylation reactions. As such, ACSS2 can recycle acetate derived from histone deacetylase reactions as well as protein deacetylation reactions mediated by sirtuins, among many others. Notably, ACSS2 can activate acetate released from acetylated metabolites including N-acetylaspartate (NAA), the most concentrated acetylated metabolite in the human brain. NAA has been associated with the metabolic reprograming of cancer cells, where ACSS2 also plays a role. Here, we discuss the context-specific roles that acetate can play in health and disease.
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Affiliation(s)
- John R. Moffett
- Department of Anatomy, Physiology and Genetics, and Neuroscience Program, Uniformed Services University of the Health Sciences, Bethesda, MD, United States
| | - Narayanan Puthillathu
- Department of Anatomy, Physiology and Genetics, and Neuroscience Program, Uniformed Services University of the Health Sciences, Bethesda, MD, United States
| | - Ranjini Vengilote
- Department of Anatomy, Physiology and Genetics, and Neuroscience Program, Uniformed Services University of the Health Sciences, Bethesda, MD, United States
| | - Diane M. Jaworski
- Department of Neurological Sciences, University of Vermont College of Medicine, Burlington, VT, United States
| | - Aryan M. Namboodiri
- Department of Anatomy, Physiology and Genetics, and Neuroscience Program, Uniformed Services University of the Health Sciences, Bethesda, MD, United States
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27
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Thoman ME, McKarns SC. Metabolomic Profiling in Neuromyelitis Optica Spectrum Disorder Biomarker Discovery. Metabolites 2020; 10:metabo10090374. [PMID: 32961928 PMCID: PMC7570337 DOI: 10.3390/metabo10090374] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2020] [Revised: 09/04/2020] [Accepted: 09/12/2020] [Indexed: 12/21/2022] Open
Abstract
There is no specific test for diagnosing neuromyelitis optica spectrum disorder (NMOSD), a disabling autoimmune disease of the central nervous system. Instead, diagnosis relies on ruling out other related disorders with overlapping clinical symptoms. An urgency for NMOSD biomarker discovery is underscored by adverse responses to treatment following misdiagnosis and poor prognosis following the delayed onset of treatment. Pathogenic autoantibiotics that target the water channel aquaporin-4 (AQP4) and myelin oligodendrocyte glycoprotein (MOG) contribute to NMOSD pathology. The importance of early diagnosis between AQP4-Ab+ NMOSD, MOG-Ab+ NMOSD, AQP4-Ab− MOG-Ab− NMOSD, and related disorders cannot be overemphasized. Here, we provide a comprehensive data collection and analysis of the currently known metabolomic perturbations and related proteomic outcomes of NMOSD. We highlight short chain fatty acids, lipoproteins, amino acids, and lactate as candidate diagnostic biomarkers. Although the application of metabolomic profiling to individual NMOSD patient care shows promise, more research is needed.
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Affiliation(s)
- Maxton E. Thoman
- Department of Surgery, University of Missouri School of Medicine, Columbia, MO 65212, USA;
- Laboratory of TGF-β Biology, Epigenetics, and Cytokine Regulation, Department of Surgery, University of Missouri School of Medicine, Columbia, MO 65212, USA
| | - Susan C. McKarns
- Department of Surgery, University of Missouri School of Medicine, Columbia, MO 65212, USA;
- Laboratory of TGF-β Biology, Epigenetics, and Cytokine Regulation, Department of Surgery, University of Missouri School of Medicine, Columbia, MO 65212, USA
- Department of Microbiology and Immunology, University of Missouri School of Medicine, Columbia, MO 65212, USA
- Correspondence:
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28
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Singh C, Tran V, McCollum L, Bolok Y, Allan K, Yuan A, Hoppe G, Brunengraber H, Sears JE. Hyperoxia induces glutamine-fuelled anaplerosis in retinal Müller cells. Nat Commun 2020; 11:1277. [PMID: 32152301 PMCID: PMC7062830 DOI: 10.1038/s41467-020-15066-6] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2019] [Accepted: 02/17/2020] [Indexed: 01/03/2023] Open
Abstract
Although supplemental oxygen is required to promote survival of severely premature infants, hyperoxia is simultaneously harmful to premature developing tissues such as in the retina. Here we report the effect of hyperoxia on central carbon metabolism in primary mouse Müller glial cells and a human Müller glia cell line (M10-M1 cells). We found decreased flux from glycolysis entering the tricarboxylic acid cycle in Müller cells accompanied by increased glutamine consumption in response to hyperoxia. In hyperoxia, anaplerotic catabolism of glutamine by Müller cells increased ammonium release two-fold. Hyperoxia induces glutamine-fueled anaplerosis that reverses basal Müller cell metabolism from production to consumption of glutamine. Prematurely born babies need extra oxygen to survive, but this can cause damage to the eyes and lead to infant blindness. Here the authors show that this hyperoxia changes the metabolism of Müller cells in the retina such that they use up, rather than produce, glutamine and secrete excess ammonium.
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Affiliation(s)
- Charandeep Singh
- Ophthalmic Research, Cole Eye Institute, Cleveland Clinic, Cleveland, OH, 44195, USA
| | - Vincent Tran
- Ophthalmic Research, Cole Eye Institute, Cleveland Clinic, Cleveland, OH, 44195, USA
| | - Leah McCollum
- Ophthalmic Research, Cole Eye Institute, Cleveland Clinic, Cleveland, OH, 44195, USA
| | - Youstina Bolok
- Ophthalmic Research, Cole Eye Institute, Cleveland Clinic, Cleveland, OH, 44195, USA
| | - Kristin Allan
- Ophthalmic Research, Cole Eye Institute, Cleveland Clinic, Cleveland, OH, 44195, USA.,Molecular Medicine, Case Western Reserve School of Medicine Cleveland, Cleveland, OH, 44106, USA
| | - Alex Yuan
- Ophthalmic Research, Cole Eye Institute, Cleveland Clinic, Cleveland, OH, 44195, USA
| | - George Hoppe
- Ophthalmic Research, Cole Eye Institute, Cleveland Clinic, Cleveland, OH, 44195, USA
| | - Henri Brunengraber
- Department of Nutrition, Case Western Reserve School of Medicine Cleveland, Cleveland, OH, 44106, USA
| | - Jonathan E Sears
- Ophthalmic Research, Cole Eye Institute, Cleveland Clinic, Cleveland, OH, 44195, USA. .,Cardiovascular and Metabolic Sciences, Cleveland Clinic, Cleveland, OH, 44195, USA.
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29
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Jakkamsetti V, Marin-Valencia I, Ma Q, Good LB, Terrill T, Rajasekaran K, Pichumani K, Khemtong C, Hooshyar MA, Sundarrajan C, Patel MS, Bachoo RM, Malloy CR, Pascual JM. Brain metabolism modulates neuronal excitability in a mouse model of pyruvate dehydrogenase deficiency. Sci Transl Med 2020; 11:11/480/eaan0457. [PMID: 30787166 DOI: 10.1126/scitranslmed.aan0457] [Citation(s) in RCA: 42] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2017] [Revised: 09/25/2018] [Accepted: 01/31/2019] [Indexed: 12/25/2022]
Abstract
Glucose is the ultimate substrate for most brain activities that use carbon, including synthesis of the neurotransmitters glutamate and γ-aminobutyric acid via mitochondrial tricarboxylic acid (TCA) cycle. Brain metabolism and neuronal excitability are thus interdependent. However, the principles that govern their relationship are not always intuitive because heritable defects of brain glucose metabolism are associated with the paradoxical coexistence, in the same individual, of episodic neuronal hyperexcitation (seizures) with reduced basal cerebral electrical activity. One such prototypic disorder is pyruvate dehydrogenase (PDH) deficiency (PDHD). PDH is central to metabolism because it steers most of the glucose-derived flux into the TCA cycle. To better understand the pathophysiology of PDHD, we generated mice with brain-specific reduced PDH activity that paralleled salient human disease features, including cerebral hypotrophy, decreased amplitude electroencephalogram (EEG), and epilepsy. The mice exhibited reductions in cerebral TCA cycle flux, glutamate content, spontaneous, and electrically evoked in vivo cortical field potentials and gamma EEG oscillation amplitude. Episodic decreases in gamma oscillations preceded most epileptiform discharges, facilitating their prediction. Fast-spiking neuron excitability was decreased in brain slices, contributing to in vivo action potential burst prolongation after whisker pad stimulation. These features were partially reversed after systemic administration of acetate, which augmented cerebral TCA cycle flux, glutamate-dependent synaptic transmission, inhibition and gamma oscillations, and reduced epileptiform discharge duration. Thus, our results suggest that dysfunctional excitability in PDHD is consequent to reduced oxidative flux, which leads to decreased neuronal activation and impaired inhibition, and can be mitigated by an alternative metabolic substrate.
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Affiliation(s)
- Vikram Jakkamsetti
- Rare Brain Disorders Program, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA.,Department of Neurology and Neurotherapeutics, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Isaac Marin-Valencia
- Rare Brain Disorders Program, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA.,Department of Neurology and Neurotherapeutics, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA.,Laboratory of Developmental Neurobiology, The Rockefeller University, New York, NY 10065, USA
| | - Qian Ma
- Rare Brain Disorders Program, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA.,Department of Neurology and Neurotherapeutics, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Levi B Good
- Rare Brain Disorders Program, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA.,Department of Neurology and Neurotherapeutics, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Tyler Terrill
- Rare Brain Disorders Program, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA.,Department of Neurology and Neurotherapeutics, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Karthik Rajasekaran
- Rare Brain Disorders Program, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA.,Department of Neurology and Neurotherapeutics, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Kumar Pichumani
- Advanced Imaging Research Center, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Chalermchai Khemtong
- Advanced Imaging Research Center, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA.,Department of Radiology, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - M Ali Hooshyar
- Department of Mathematical Sciences, The University of Texas at Dallas, Richardson, TX 75080, USA
| | - Chandrasekhar Sundarrajan
- Rare Brain Disorders Program, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA.,Department of Neurology and Neurotherapeutics, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Mulchand S Patel
- Department of Biochemistry, SUNY Buffalo, Buffalo, NY 14203, USA
| | - Robert M Bachoo
- Department of Neurology and Neurotherapeutics, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA.,Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Craig R Malloy
- Advanced Imaging Research Center, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA.,Department of Radiology, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA.,Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Juan M Pascual
- Rare Brain Disorders Program, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA. .,Department of Neurology and Neurotherapeutics, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA.,Department of Physiology, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA.,Department of Pediatrics, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA.,Eugene McDermott Center for Human Growth & Development / Center for Human Genetics, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
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30
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Wilson DF, Matschinsky FM. Ethanol metabolism: The good, the bad, and the ugly. Med Hypotheses 2020; 140:109638. [PMID: 32113062 DOI: 10.1016/j.mehy.2020.109638] [Citation(s) in RCA: 46] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2020] [Revised: 02/14/2020] [Accepted: 02/17/2020] [Indexed: 12/20/2022]
Abstract
Throughout the world, ethanol is both an important commercial commodity and a source of major medical and social problems. Ethanol readily passes through biological membranes and distributes throughout the body. It is oxidized, first to acetaldehyde and then to acetate, and finally by the citric acid cycle in virtually all tissues. The oxidation of ethanol is irreversible and unregulated, making the rate dependent only on local concentration and enzyme activity. This unregulated input of reducing equivalents increases reduction of both cytoplasmic and intramitochondrial NAD and, through the latter, cellular energy state {[ATP]/([ADP][Pi])}. In brain, this increase in energy state stimulates dopaminergic neural activity signalling reward and a sense of well being, while suppressing glutamatergic neural activity signalling anxiety and unease. These positive responses to ethanol ingestion are important to social alcohol consumption. Importantly, decreased free [AMP] decreases AMP-dependent protein kinase (AMPK) activity, an important regulator of cellular energy metabolism. Oxidation of substrates used for energy metabolism in the absence of ethanol is down regulated to accommodate the input from ethanol. In liver, chronic ethanol metabolism results in fatty liver and general metabolic dysfunction. In brain, transport of other oxidizable metabolites through the blood-brain barrier and the enzymes for their oxidation are both down regulated. For exposures of short duration, ethanol induced regulatory changes are rapid and reversible, recovering completely when the concentrations of ethanol and acetate fall again. Longer periods of ethanol exposure and associated chronic suppression of AMPK activity activates regulatory mechanisms, including gene expression, that operate over longer time scales, both in onset and reversal. If chronic alcohol consumption is abruptly ended, metabolism is no longer able to respond rapidly enough to compensate. Glutamatergic neural activity adapts to chronic dysregulation of glutamate metabolism and suppression of glutamatergic neural activity by increasing excitatory and decreasing inhibitory amino acid receptors. A point is reached (ethanol dependence) where withdrawal of ethanol results in significant metabolic energy depletion in neurons and other brain cells as well as hyperexcitation of the glutamatergic system. The extent and regional specificity of energy depletion in the brain, combined with hyperactivity of the glutamatergic neuronal system, largely determines the severity of withdrawal symptoms.
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Affiliation(s)
- David F Wilson
- Department of Biochemistry and Biophysics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, United States.
| | - Franz M Matschinsky
- Department of Biochemistry and Biophysics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, United States.
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31
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Tanabe J, Yamamoto DJ, Sutton B, Brown MS, Hoffman PL, Burnham EL, Glueck DH, Tabakoff B. Effects of Alcohol and Acetate on Cerebral Blood Flow: A Pilot Study. Alcohol Clin Exp Res 2019; 43:2070-2078. [PMID: 31386214 PMCID: PMC7066986 DOI: 10.1111/acer.14173] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2019] [Accepted: 07/25/2019] [Indexed: 12/18/2022]
Abstract
BACKGROUND Acute alcohol produces effects on cerebral metabolism and blood flow. Alcohol is converted to acetate, which serves as a source of energy for the brain and is an agonist at G protein-coupled receptors distributed in different cell types in the body including neurons. Acetate has been hypothesized to play a role in the cerebral blood flow (CBF) response after alcohol ingestion. We tested whether administration of acetate would alter CBF in a pattern similar to or different from that of alcohol ingestion in healthy individuals. METHODS Twenty-four healthy participants were assigned by convenience to receive either 0.6 g/kg alcohol orally (n = 12) or acetate intravenously (n = 12). For each participant, CBF maps were acquired using an arterial spin labeling sequence on a 3T magnetic resonance scanner after placebo and after drug administration. Whole-brain CBF maps were compared between placebo and drug using a paired t-test, and set at a threshold of p < 0.05 corrected for multiple comparisons (k ≥ 142 voxels, ≥3.78 cm3 ), voxel-level p < 0.005. Intoxication was measured after placebo and drug administration with a Subjective High Assessment Scale (SHAS-7). RESULTS Compared to placebo, alcohol and acetate were associated with increased CBF in the medial thalamus. Alcohol, but not acetate, was associated with increased CBF in the right orbitofrontal, medial prefrontal and cingulate cortex, and hippocampus. Plasma acetate levels increased following administration of alcohol and acetate and did not differ between the 2 arms. Alcohol, but not acetate, was associated with an increase in SHAS-7 scores (p < 0.001). CONCLUSIONS Increased thalamic CBF associated with either alcohol or acetate administration suggests that the thalamic CBF response after alcohol could be mediated by acetate. Compared to other brain regions, thalamus may differ in its ability to metabolize acetate or expression of receptors responsive to acetate. Increased prefrontal and limbic CBF associated with alcohol may be linked to alcohol's behavioral effects.
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Affiliation(s)
- Jody Tanabe
- Department of Radiology, School of Medicine, University of
Colorado Anschutz Medical Campus, Aurora, CO, 80045, USA
- Department of Psychiatry, School of Medicine, University of
Colorado Anschutz Medical Campus, Aurora, CO, 80045, USA
| | - Dorothy J. Yamamoto
- Department of Radiology, School of Medicine, University of
Colorado Anschutz Medical Campus, Aurora, CO, 80045, USA
| | - Brianne Sutton
- Department of Radiology, School of Medicine, University of
Colorado Anschutz Medical Campus, Aurora, CO, 80045, USA
- Department of Psychiatry, School of Medicine, University of
Colorado Anschutz Medical Campus, Aurora, CO, 80045, USA
| | - Mark S. Brown
- Department of Radiology, School of Medicine, University of
Colorado Anschutz Medical Campus, Aurora, CO, 80045, USA
| | - Paula L. Hoffman
- Department of Pharmacology, School of Medicine, University
of Colorado Anschutz Medical Campus, Aurora, CO, 80045, USA
| | - Ellen L. Burnham
- Department of Medicine, School of Medicine, University of
Colorado Anschutz Medical Campus, Aurora, CO, 80045, USA
| | - Deborah H. Glueck
- Department of Pediatrics, School of Medicine, University of
Colorado Anschutz Medical Campus, Aurora, CO, 80045, USA
| | - Boris Tabakoff
- Department of Pharmaceutical Sciences, School of Pharmacy,
University of Colorado Anschutz Medical Campus, Aurora, CO, 80045, USA
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Tefera TW, Borges K. Neuronal glucose metabolism is impaired while astrocytic TCA cycling is unaffected at symptomatic stages in the hSOD1 G93A mouse model of amyotrophic lateral sclerosis. J Cereb Blood Flow Metab 2019; 39:1710-1724. [PMID: 29553298 PMCID: PMC6727138 DOI: 10.1177/0271678x18764775] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Although alterations in energy metabolism are known in ALS, the specific mechanisms leading to energy deficit are not understood. We measured metabolite levels derived from injected [1-13C]glucose and [1,2-13C]acetate (i.p.) in cerebral cortex and spinal cord extracts of wild type and hSOD1G93A mice at onset and mid disease stages using high-pressure liquid chromatography, 1H and 13C nuclear magnetic resonance spectroscopy. Levels of spinal and cortical CNS total lactate, [3-13C]lactate, total alanine and [3-13C]alanine, but not cortical glucose and [1-13C]glucose, were reduced mostly at mid stage indicating impaired glycolysis. The [1-13C]glucose-derived [4-13C]glutamate, [4-13C]glutamine and [2-13C]GABA amounts were diminished at mid stage in cortex and both time points in spinal cord, suggesting decreased [3-13C]pyruvate entry into the TCA cycle. Lack of changes in [1,2-13C]acetate-derived [4,5-13C]glutamate, [4,5-13C]glutamine and [1,2-13C]GABA levels indicate unchanged astrocytic 13C-acetate metabolism. Reduced levels of leucine, isoleucine and valine in CNS suggest compensatory breakdown to refill TCA cycle intermediate levels. Unlabelled, [2-13C] and [4-13C]GABA concentrations were decreased in spinal cord indicating that impaired glucose metabolism contributes to hyperexcitability and supporting the use of treatments which increase GABA amounts. In conclusion, CNS glucose metabolism is compromised, while astrocytic TCA cycling appears to be normal in the hSOD1G93A mouse model at symptomatic disease stages.
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Affiliation(s)
- Tesfaye W Tefera
- Department of Pharmacology, School of Biomedical Sciences, Faculty of Medicine, The University of Queensland, Brisbane, QLD, Australia
| | - Karin Borges
- Department of Pharmacology, School of Biomedical Sciences, Faculty of Medicine, The University of Queensland, Brisbane, QLD, Australia
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Macaisa CM, Watabe T, Liu Y, Romanov V, Kanai Y, Horitsugi G, Kato H, Shimosegawa E, Hatazawa J. Preserved Cerebral Oxygen Metabolism in Astrocytic Dysfunction: A Combination Study of 15O-Gas PET with 14C-Acetate Autoradiography. Brain Sci 2019; 9:brainsci9050101. [PMID: 31058865 PMCID: PMC6562644 DOI: 10.3390/brainsci9050101] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2019] [Revised: 04/24/2019] [Accepted: 04/29/2019] [Indexed: 02/07/2023] Open
Abstract
Fluorocitrate (FC) is a specific metabolic inhibitor of the tricarboxylic acid (TCA) cycle in astrocytes. The purpose of this study was to evaluate whether inhibition of the astrocyte TCA cycle by FC would affect the oxygen metabolism in the rat brain. At 4 h after the intracranial FC injection, the rats (n = 9) were investigated by 15O-labeled gas PET to measure the cerebral blood flow (CBF), the cerebral metabolic rate of oxygen (CMRO2), oxygen extraction fraction (OEF), and cerebral blood volume (CBV). After the 15O-gas PET, the rats were given an intravenous injection of 14C-acetate for autoradiography. 15O-gas PET showed no significant differences in any of the measured parameters between the ipsilateral and contralateral striatum (high dose group: CBF (54.4 ± 8.8 and 55.3 ± 11.6 mL/100mL/min), CMRO2 (7.0 ± 0.9 and 7.1 ± 1.2 mL/100mL/min), OEF (72.0 ± 8.9 and 70.8 ± 8.2%), and CBV (4.1 ± 0.8 and 4.2 ± 0.9 mL/100mL), respectively). In contrast, the 14C-acetate autoradiography revealed a significant inhibition of the astrocyte metabolism in the ipsilateral striatum. The regional cerebral oxygen consumption as well as the hemodynamic parameters were maintained even in the face of inhibition of the astrocyte TCA cycle metabolism in the rat brain.
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Affiliation(s)
- Carla Mari Macaisa
- Department of Nuclear Medicine and Tracer Kinetics, Osaka University Graduate School of Medicine, Suita 565-0871, Japan.
| | - Tadashi Watabe
- Department of Nuclear Medicine and Tracer Kinetics, Osaka University Graduate School of Medicine, Suita 565-0871, Japan.
| | - Yuwei Liu
- Department of Nuclear Medicine and Tracer Kinetics, Osaka University Graduate School of Medicine, Suita 565-0871, Japan.
| | - Victor Romanov
- Department of Nuclear Medicine and Tracer Kinetics, Osaka University Graduate School of Medicine, Suita 565-0871, Japan.
| | - Yasukazu Kanai
- Department of Molecular Imaging in Medicine, Osaka University Graduate School of Medicine,Suita 565-0871, Japan.
| | - Genki Horitsugi
- Department of Nuclear Medicine and Tracer Kinetics, Osaka University Graduate School of Medicine, Suita 565-0871, Japan.
| | - Hiroki Kato
- Department of Nuclear Medicine and Tracer Kinetics, Osaka University Graduate School of Medicine, Suita 565-0871, Japan.
| | - Eku Shimosegawa
- Department of Molecular Imaging in Medicine, Osaka University Graduate School of Medicine,Suita 565-0871, Japan.
| | - Jun Hatazawa
- Department of Nuclear Medicine and Tracer Kinetics, Osaka University Graduate School of Medicine, Suita 565-0871, Japan.
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Oyarzabal A, Marin-Valencia I. Synaptic energy metabolism and neuronal excitability, in sickness and health. J Inherit Metab Dis 2019; 42:220-236. [PMID: 30734319 DOI: 10.1002/jimd.12071] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/29/2018] [Revised: 01/06/2019] [Accepted: 01/30/2019] [Indexed: 12/11/2022]
Abstract
Most of the energy produced in the brain is dedicated to supporting synaptic transmission. Glucose is the main fuel, providing energy and carbon skeletons to the cells that execute and support synaptic function: neurons and astrocytes, respectively. It is unclear, however, how glucose is provided to and used by these cells under different levels of synaptic activity. It is even more unclear how diseases that impair glucose uptake and oxidation in the brain alter metabolism in neurons and astrocytes, disrupt synaptic activity, and cause neurological dysfunction, of which seizures are one of the most common clinical manifestations. Poor mechanistic understanding of diseases involving synaptic energy metabolism has prevented the expansion of therapeutic options, which, in most cases, are limited to symptomatic treatments. To shed light on the intersections between metabolism, synaptic transmission, and neuronal excitability, we briefly review current knowledge of compartmentalized metabolism in neurons and astrocytes, the biochemical pathways that fuel synaptic transmission at resting and active states, and the mechanisms by which disorders of brain glucose metabolism disrupt neuronal excitability and synaptic function and cause neurological disease in the form of epilepsy.
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Affiliation(s)
- Alfonso Oyarzabal
- Synaptic Metabolism Laboratory, Department of Neurology, Hospital Sant Joan de Deu, Barcelona, Spain
| | - Isaac Marin-Valencia
- Laboratory of Developmental Neurobiology, The Rockefeller University, New York, New York
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35
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Correspondence between cerebral glucose metabolism and BOLD reveals relative power and cost in human brain. Nat Commun 2019; 10:690. [PMID: 30741935 PMCID: PMC6370887 DOI: 10.1038/s41467-019-08546-x] [Citation(s) in RCA: 51] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2018] [Accepted: 01/17/2019] [Indexed: 12/02/2022] Open
Abstract
The correspondence between cerebral glucose metabolism (indexing energy utilization) and synchronous fluctuations in blood oxygenation (indexing neuronal activity) is relevant for neuronal specialization and is affected by brain disorders. Here, we define novel measures of relative power (rPWR, extent of concurrent energy utilization and activity) and relative cost (rCST, extent that energy utilization exceeds activity), derived from FDG-PET and fMRI. We show that resting-state networks have distinct energetic signatures and that brain could be classified into major bilateral segments based on rPWR and rCST. While medial-visual and default-mode networks have the highest rPWR, frontoparietal networks have the highest rCST. rPWR and rCST estimates are generalizable to other indexes of energy supply and neuronal activity, and are sensitive to neurocognitive effects of acute and chronic alcohol exposure. rPWR and rCST are informative metrics for characterizing brain pathology and alternative energy use, and may provide new multimodal biomarkers of neuropsychiatric disorders. The brain primarily uses glucose to generate energy, but the relationship of neuronal activity to glucose utilization is not necessarily a simple linear one. Here, the authors introduce relative power (rPWR) and relative cost (rCST) as new metrics to quantify how brain activity relates to glucose consumption.
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36
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Chapp AD, Behnke JE, Driscoll KM, Fan Y, Hoban E, Shan Z, Zhang L, Chen QH. Acetate Mediates Alcohol Excitotoxicity in Dopaminergic-like PC12 Cells. ACS Chem Neurosci 2019; 10:235-245. [PMID: 30247872 DOI: 10.1021/acschemneuro.8b00189] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
Neuronal excitotoxicity is the major cause of alcohol-related brain damage, yet the underlying mechanism remains poorly understood. Using dopaminergic-like PC12 cells, we evaluated the effect of N-methyl-d-aspartate receptors (NMDAR) on acetate-induced changes in PC12 cells: cell death, cytosolic calcium, and expression levels of the pro-inflammatory cytokine tumor necrosis factor alpha (TNFα). Treatment of PC12 cells with increasing concentrations of acetate for 4 h caused a dose-dependent increase in the percentage of cells staining positive for cell death using propidium iodide (PI) exclusion and cytosolic reactive oxygen species (ROS) using cell ROX detection analyzed via flow cytometry. The EC50 value for acetate was calculated and found to be 4.40 mM for PI and 1.81 mM for ROS. Ethanol up to 100 mM had no apparent changes in the percent of cells staining positive for PI or ROS. Acetate (6 mM) treatment caused an increase in cytosolic calcium measured in real-time with Fluo-4AM, which was abolished by coapplication with the NMDAR blocker memantine (10 μM). Furthermore, cells treated with acetate (6 mM) for 4 h had increased expression levels of TNFα relative to control, which was abolished by coapplication of memantine (10 μM). Co-application of acetate (6 mM) and memantine had no apparent reduction in acetate-induced cell death. These findings suggest that acetate is capable of increasing cytosolic calcium concentrations and expression levels of the pro-inflammatory cytokine TNFα through an NMDAR-dependent mechanism. Cell death from acetate was not reduced through NMDAR blockade, suggesting alternative pathways independent of NMDAR activation for excitotoxicity.
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Affiliation(s)
- Andrew D. Chapp
- Department of Kinesiology and Integrative Physiology, Michigan Technological University, Houghton, Michigan 49931, United States
- Department of Biological Sciences, Michigan Technological University, Houghton, Michigan 49931, United States
| | - Jessica E. Behnke
- Department of Biological Sciences, Michigan Technological University, Houghton, Michigan 49931, United States
| | - Kyle M. Driscoll
- Department of Biological Sciences, Michigan Technological University, Houghton, Michigan 49931, United States
| | - Yuanyuan Fan
- Department of Kinesiology and Integrative Physiology, Michigan Technological University, Houghton, Michigan 49931, United States
| | - Eileen Hoban
- Department of Biological Sciences, Michigan Technological University, Houghton, Michigan 49931, United States
| | - Zhiying Shan
- Department of Kinesiology and Integrative Physiology, Michigan Technological University, Houghton, Michigan 49931, United States
- Department of Biological Sciences, Michigan Technological University, Houghton, Michigan 49931, United States
| | - Li Zhang
- Laboratory for Integrative Neuroscience, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Rockville, Maryland 20852, United States
| | - Qing-Hui Chen
- Department of Kinesiology and Integrative Physiology, Michigan Technological University, Houghton, Michigan 49931, United States
- Department of Biological Sciences, Michigan Technological University, Houghton, Michigan 49931, United States
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37
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Brain metabolic and functional alterations in a liver-specific PTEN knockout mouse model. PLoS One 2018; 13:e0204043. [PMID: 30235271 PMCID: PMC6147462 DOI: 10.1371/journal.pone.0204043] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2018] [Accepted: 08/31/2018] [Indexed: 01/11/2023] Open
Abstract
Insulin resistance-as observed in aging, diabetes, obesity, and other pathophysiological situations, affects brain function, for insulin signaling is responsible for neuronal glucose transport and control of energy homeostasis and is involved in the regulation of neuronal growth and synaptic plasticity. This study investigates brain metabolism and function in a liver-specific Phosphatase and Tensin Homologue (Pten) knockout mouse model (Liver-PtenKO), a negative regulator of insulin signaling. The Liver-PtenKO mouse model showed an increased flux of glucose into the liver-thus resulting in an overall hypoglycemic and hypoinsulinemic state-and significantly lower hepatic production of the ketone body beta-hydroxybutyrate (as compared with age-matched control mice). The Liver-PtenKO mice exhibited increased brain glucose uptake, improved rate of glycolysis and flux of metabolites in the TCA cycle, and improved synaptic plasticity in the hippocampus. Brain slices from both control- and Liver-PtenKO mice responded to the addition of insulin (in terms of pAKT/AKT levels), thereby neglecting an insulin resistance scenario. This study underscores the significance of insulin signaling in brain bioenergetics and function and helps recognize deficits in diseases associated with insulin resistance.
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38
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Patel AB, Tiwari V, Veeraiah P, Saba K. Increased astroglial activity and reduced neuronal function across brain in AβPP-PS1 mouse model of Alzheimer's disease. J Cereb Blood Flow Metab 2018; 38:1213-1226. [PMID: 28585882 PMCID: PMC6434450 DOI: 10.1177/0271678x17709463] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Alzheimer's disease (AD) is the most common neurodegenerative disease associated with progressive loss of cognitive function, personality, and behavior. The present study evaluates neuronal and astroglial metabolic activity, and neurotransmitter cycle fluxes in AβPP-PS1 mouse model of AD by using 1H-[13C]-nuclear magnetic resonance (NMR) spectroscopy together with an infusion of either [1,6-13C2]glucose or [2-13C]acetate. The levels of N-acetyl-aspartate (NAA) and glutamate were found to be decreased in the cerebral cortex and hippocampus in AβPP-PS1 mice, when compared with wild type controls. The cerebral metabolic rate of acetate oxidation was increased in the hippocampus and cerebral cortex of AβPP-PS1 mice suggesting enhanced astroglial activity in AD. AβPP-PS1 mice exhibit severe reduction in glutamatergic and gamma-amino butyric acid (GABA)ergic neuronal metabolic activity and neurotransmitter cycling fluxes in the hippocampus, cerebral cortex, and striatum as compared with controls. These data suggest that metabolic activity of excitatory and inhibitory neurons is compromised across brain in AβPP-PS1 mouse model of AD.
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Affiliation(s)
- Anant B Patel
- CSIR-Centre for Cellular and Molecular Biology, Hyderabad, India
| | - Vivek Tiwari
- CSIR-Centre for Cellular and Molecular Biology, Hyderabad, India
| | | | - Kamal Saba
- CSIR-Centre for Cellular and Molecular Biology, Hyderabad, India
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The roles of 11C-acetate PET/CT in predicting tumor differentiation and survival in patients with cerebral glioma. Eur J Nucl Med Mol Imaging 2018; 45:1012-1020. [PMID: 29511838 DOI: 10.1007/s00259-018-3948-9] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2017] [Accepted: 01/11/2018] [Indexed: 12/15/2022]
Abstract
PURPOSE This prospective study aimed to evaluate the clinical values of 11C-acetate positron emission tomography/computed tomography (PET/CT) in predicting histologic grades and survival in patients with cerebral glioma. METHODS Seventy-three patients with surgically confirmed cerebral gliomas (19 grade II, 21 grade III, and 33 grade IV) who underwent 11C-acetate PET/CT before surgery were included. Tumor-to-choroid plexus ratio (TCR), which was defined as the maximum standardized uptake value (SUV) of tumors to the mean SUV of choroid plexus, was compared between three World Health Organization (WHO) grade groups. Moreover, metabolic tumor volumes (MTV) were calculated. Progression-free survival (PFS) and overall survival (OS) curves were plotted using the Kaplan-Meier method, and differences in survival between groups were assessed using the log-rank test. RESULTS Median TCR was 1.20 (interquartile range [IQR], 1.14 to 1.4) in grade II, 1.65 (IQR, 1.26 to 1.79) in grade III, and 2.53 (IQR, 1.93 to 3.30) in grade IV gliomas. Significant differences in TCR were seen among the three WHO grade groups (P < 0.001). In Cox regression analysis including TCR, MTV, molecular markers, and other clinical factors, TCR was prognostic for PFS (P = 0.016) and TCR and MTV were prognostic for OS (P = 0.024 [TCR], P = 0.030 [MTV]). PFS and OS were significantly shorter in patients with a TCR ≥ 1.6 than in those with a TCR < 1.6. OS were significantly shorter in patients with a MTV ≥ 1 than in those with a TCR < 1. CONCLUSIONS TCR on 11C-acetate PET/CT significantly differed between low- and high-grade cerebral gliomas, and it showed the capability to further differentiate grade III from grade IV tumors. TCR and MTV were independent prognostic factors and predicted survival better than did the WHO grade.
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Abstract
Magnetic Resonance Spectroscopy is a technique that has the capability of measuring metabolites in vivo and, in appropriate conditions, to infer its metabolic rates. The success of MRS depends a lot on its sensitivity, which limits the usage of X-nuclei MRS. However, technological developments and refinements in methods have made in vivo heteronuclear MRS possible in humans and in small animals. This chapter provides detailed descriptions of the main procedures needed to perform successful in vivo heteronuclear MRS experiments, with a particular focus on experimental setup in 13C MRS experiments in rodents.
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Affiliation(s)
- Blanca Lizarbe
- Laboratory for Functional and Metabolic Imaging (LIFMET), École Polytechnique Fédérale de Lausanne, Lausanne, Switzerland.
| | - Antoine Cherix
- Laboratory for Functional and Metabolic Imaging (LIFMET), École Polytechnique Fédérale de Lausanne, Lausanne, Switzerland
| | - Rolf Gruetter
- Laboratory for Functional and Metabolic Imaging (LIFMET), École Polytechnique Fédérale de Lausanne, Lausanne, Switzerland.,Department of Radiology, University of Geneva, Geneva, Switzerland.,Department of Radiology, University of Lausanne, Lausanne, Switzerland
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41
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Choi JY, Park M, Cho H, Kim MH, Kang K, Choi IS. Neuro-Compatible Metabolic Glycan Labeling of Primary Hippocampal Neurons in Noncontact, Sandwich-Type Neuron-Astrocyte Coculture. ACS Chem Neurosci 2017; 8:2607-2612. [PMID: 28953350 DOI: 10.1021/acschemneuro.7b00300] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Glycans are intimately involved in several facets of neuronal development and neuropathology. However, the metabolic labeling of surface glycans in primary neurons is a difficult task because of the neurotoxicity of unnatural monosaccharides that are used as a metabolic precursor, hindering the progress of metabolic engineering in neuron-related fields. Therefore, in this paper, we report a neurosupportive, neuron-astrocyte coculture system that neutralizes the neurotoxic effects of unnatural monosaccharides, allowing for the long-term observation and characterization of glycans in primary neurons in vitro. Polysialic acids in neurons are selectively imaged, via the metabolic labeling of sialoglycans with peracetylated N-azidoacetyl-d-mannosamine (Ac4ManNAz), for up to 21 DIV. Two-color labeling shows that neuronal activities, such as neurite outgrowth and recycling of membrane components, are highly dynamic and change over time during development. In addition, the insertion sites of membrane components are suggested to not be random, but be predominantly localized in developing neurites. This work provides a new research platform and also suggests advanced 3D systems for metabolic-labeling studies of glycans in primary neurons.
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Affiliation(s)
- Ji Yu Choi
- Center
for Cell-Encapsulation Research, Department of Chemistry, KAIST, Daejeon 34141, Korea
| | - Matthew Park
- Center
for Cell-Encapsulation Research, Department of Chemistry, KAIST, Daejeon 34141, Korea
| | - Hyeoncheol Cho
- Center
for Cell-Encapsulation Research, Department of Chemistry, KAIST, Daejeon 34141, Korea
| | - Mi-Hee Kim
- Center
for Cell-Encapsulation Research, Department of Chemistry, KAIST, Daejeon 34141, Korea
| | - Kyungtae Kang
- Department
of Applied Chemistry, Kyung Hee University, Yongin, Gyeonggi 17104, Korea
| | - Insung S. Choi
- Center
for Cell-Encapsulation Research, Department of Chemistry, KAIST, Daejeon 34141, Korea
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Hsieh YJ, Wu LC, Ke CC, Chang CW, Kuo JW, Huang WS, Chen FD, Yang BH, Tai HT, Chen SCJ, Liu RS. Effects of the Acute and Chronic Ethanol Intoxication on Acetate Metabolism and Kinetics in the Rat Brain. Alcohol Clin Exp Res 2017; 42:329-337. [PMID: 29205407 DOI: 10.1111/acer.13573] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2017] [Accepted: 11/20/2017] [Indexed: 10/18/2022]
Abstract
BACKGROUND Ethanol (EtOH) intoxication inhibits glucose transport and decreases overall brain glucose metabolism; however, humans with long-term EtOH consumption were found to have a significant increase in [1-11 C]-acetate uptake in the brain. The relationship between the cause and effect of [1-11 C]-acetate kinetics and acute/chronic EtOH intoxication, however, is still unclear. METHODS [1-11 C]-acetate positron emission tomography (PET) with dynamic measurement of K1 and k2 rate constants was used to investigate the changes in acetate metabolism in different brain regions of rats with acute or chronic EtOH intoxication. RESULTS PET imaging demonstrated decreased [1-11 C]-acetate uptake in rat brain with acute EtOH intoxication, but this increased with chronic EtOH intoxication. Tracer uptake rate constant K1 and clearance rate constant k2 were decreased in acutely intoxicated rats. No significant change was noted in K1 and k2 in chronic EtOH intoxication, although 6 of 7 brain regions showed slightly higher k2 than baseline. These results indicate that acute EtOH intoxication accelerated acetate transport and metabolism in the rat brain, whereas chronic EtOH intoxication status showed no significant effect. CONCLUSIONS In vivo PET study confirmed the modulatory role of EtOH, administered acutely or chronically, in [1-11 C]-acetate kinetics and metabolism in the rat brain. Acute EtOH intoxication may inhibit the transport and metabolism of acetate in the brain, whereas chronic EtOH exposure may lead to the adaptation of the rat brain to EtOH in acetate utilization. [1-11 C]-acetate PET imaging is a feasible approach to study the effect of EtOH on acetate metabolism in rat brain.
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Affiliation(s)
- Ya-Ju Hsieh
- Department of Medical Imaging and Radiological Sciences, Kaohsiung Medical University, Kaohsiung, Taiwan.,Department of Medical Research, Kaohsiung Medical University Hospital, Kaohsiung, Taiwan
| | - Liang-Chih Wu
- National PET/Cyclotron Center, Department of Nuclear Medicine, Taipei Veterans General Hospital, Taipei, Taiwan
| | - Chien-Chih Ke
- Biomedical Imaging Research Center, National Yang-Ming University, Taipei, Taiwan.,Molecular and Genetic Imaging Core/Taiwan Mouse Clinic, National Comprehensive Mouse Phenotyping and Drug Testing Center, Taipei, Taiwan
| | - Chi-Wei Chang
- National PET/Cyclotron Center, Department of Nuclear Medicine, Taipei Veterans General Hospital, Taipei, Taiwan
| | - Jung-Wen Kuo
- Biomedical Imaging Research Center, National Yang-Ming University, Taipei, Taiwan.,Molecular and Genetic Imaging Core/Taiwan Mouse Clinic, National Comprehensive Mouse Phenotyping and Drug Testing Center, Taipei, Taiwan
| | - Wen-Sheng Huang
- National PET/Cyclotron Center, Department of Nuclear Medicine, Taipei Veterans General Hospital, Taipei, Taiwan
| | - Fu-Du Chen
- Biomedical Imaging Research Center, National Yang-Ming University, Taipei, Taiwan.,Department of Biomedical Imaging and Radiological Sciences, National Yang-Ming University, Taipei, Taiwan
| | - Bang-Hung Yang
- National PET/Cyclotron Center, Department of Nuclear Medicine, Taipei Veterans General Hospital, Taipei, Taiwan.,Department of Biomedical Imaging and Radiological Sciences, National Yang-Ming University, Taipei, Taiwan
| | - Hsiao-Ting Tai
- Department of Medical Research, Kaohsiung Medical University Hospital, Kaohsiung, Taiwan
| | - Sharon Chia-Ju Chen
- Department of Medical Imaging and Radiological Sciences, Kaohsiung Medical University, Kaohsiung, Taiwan
| | - Ren-Shyan Liu
- National PET/Cyclotron Center, Department of Nuclear Medicine, Taipei Veterans General Hospital, Taipei, Taiwan.,Biomedical Imaging Research Center, National Yang-Ming University, Taipei, Taiwan.,Molecular and Genetic Imaging Core/Taiwan Mouse Clinic, National Comprehensive Mouse Phenotyping and Drug Testing Center, Taipei, Taiwan.,Department of Biomedical Imaging and Radiological Sciences, National Yang-Ming University, Taipei, Taiwan.,Institute of Clinical Medicine, National Yang-Ming University, Taipei, Taiwan.,Biophotonic and Molecular Imaging Research Center, National Yang-Ming University, Taipei, Taiwan.,Department of Nuclear Medicine, Cheng-Hsin General Hospital, Taipei, Taiwan
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43
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Beltrán-Castillo S, Olivares MJ, Contreras RA, Zúñiga G, Llona I, von Bernhardi R, Eugenín JL. D-serine released by astrocytes in brainstem regulates breathing response to CO 2 levels. Nat Commun 2017; 8:838. [PMID: 29018191 PMCID: PMC5635109 DOI: 10.1038/s41467-017-00960-3] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2016] [Accepted: 08/09/2017] [Indexed: 11/17/2022] Open
Abstract
Central chemoreception is essential for adjusting breathing to physiological demands, and for maintaining CO2 and pH homeostasis in the brain. CO2-induced ATP release from brainstem astrocytes stimulates breathing. NMDA receptor (NMDAR) antagonism reduces the CO2-induced hyperventilation by unknown mechanisms. Here we show that astrocytes in the mouse caudal medullary brainstem can synthesize, store, and release d-serine, an agonist for the glycine-binding site of the NMDAR, in response to elevated CO2 levels. We show that systemic and raphe nucleus d-serine administration to awake, unrestrained mice increases the respiratory frequency. Application of d-serine to brainstem slices also increases respiratory frequency, which was prevented by NMDAR blockade. Inhibition of d-serine synthesis, enzymatic degradation of d-serine, or the sodium fluoroacetate-induced impairment of astrocyte functions decrease the basal respiratory frequency and the CO2-induced respiratory response in vivo and in vitro. Our findings suggest that astrocytic release of d-serine may account for the glutamatergic contribution to central chemoreception. Astrocytes are involved in chemoreception in brainstem areas that regulate breathing rhythm, and astrocytes are known to release d-serine. Here the authors show that astrocyte release of d-serine contributes to CO2 sensing and breathing in brainstem slices, and in vivo in awake unrestrained mice.
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Affiliation(s)
- S Beltrán-Castillo
- Departamento de Biología, Facultad de Química y Biología, Universidad de Santiago de Chile, USACH, Santiago, 9170022, Chile
| | - M J Olivares
- Departamento de Biología, Facultad de Química y Biología, Universidad de Santiago de Chile, USACH, Santiago, 9170022, Chile
| | - R A Contreras
- Departamento de Biología, Facultad de Química y Biología, Universidad de Santiago de Chile, USACH, Santiago, 9170022, Chile
| | - G Zúñiga
- Departamento de Biología, Facultad de Química y Biología, Universidad de Santiago de Chile, USACH, Santiago, 9170022, Chile
| | - I Llona
- Departamento de Biología, Facultad de Química y Biología, Universidad de Santiago de Chile, USACH, Santiago, 9170022, Chile
| | - R von Bernhardi
- Departamento de Neurología, Facultad de Medicina, Pontificia Universidad Católica de Chile, Santiago, 8330024, Chile.
| | - J L Eugenín
- Departamento de Biología, Facultad de Química y Biología, Universidad de Santiago de Chile, USACH, Santiago, 9170022, Chile.
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44
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Dehghani M, Kunz N, Lanz B, Yoshihara HAI, Gruetter R. Diffusion-weighted MRS of acetate in the rat brain. NMR IN BIOMEDICINE 2017; 30:e3768. [PMID: 28796319 DOI: 10.1002/nbm.3768] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/06/2016] [Revised: 05/04/2017] [Accepted: 05/31/2017] [Indexed: 06/07/2023]
Abstract
Acetate has been proposed as an astrocyte-specific energy substrate for metabolic studies in the brain. The determination of the relative contribution of the intracellular and extracellular compartments to the acetate signal using diffusion-weighted magnetic resonance spectroscopy can provide an insight into the cellular environment and distribution volume of acetate in the brain. In the present study, localized 1 H nuclear magnetic resonance (NMR) spectroscopy employing a diffusion-weighted stimulated echo acquisition mode (STEAM) sequence at an ultra-high magnetic field (14.1 T) was used to investigate the diffusivity characteristics of acetate and N-acetylaspartate (NAA) in the rat brain in vivo during prolonged acetate infusion. The persistence of the acetate resonance in 1 H spectra acquired at very large diffusion weighting indicated restricted diffusion of acetate and was attributed to intracellular spaces. However, the significantly greater diffusion of acetate relative to NAA suggests that a substantial fraction of acetate is located in the extracellular space of the brain. Assuming an even distribution for acetate in intracellular and extracellular spaces, the diffusion properties of acetate yielded a smaller volume of distribution for acetate relative to water and glucose in the rat brain.
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Affiliation(s)
- Masoumeh Dehghani
- Laboratoire d'imagerie fonctionnelle et métabolique (LIFMET), École polytechnique fédérale de Lausanne (EPFL), Lausanne, Switzerland
| | - Nicolas Kunz
- Centre d'Imagerie BioMédicale (CIBM)-AIT, École polytechnique fédérale de Lausanne (EPFL), Lausanne, Switzerland
| | - Bernard Lanz
- Laboratoire d'imagerie fonctionnelle et métabolique (LIFMET), École polytechnique fédérale de Lausanne (EPFL), Lausanne, Switzerland
- Sir Peter Mansfield Imaging Centre, School of Physics and Astronomy, University of Nottingham, Nottingham, UK
| | - Hikari A I Yoshihara
- Service de Cardiologie, Centre Hospitalier Universitaire Vaudois (CHUV), Lausanne, Switzerland
| | - Rolf Gruetter
- Laboratoire d'imagerie fonctionnelle et métabolique (LIFMET), École polytechnique fédérale de Lausanne (EPFL), Lausanne, Switzerland
- Centre d'Imagerie BioMédicale (CIBM), École polytechnique fédérale de Lausanne (EPFL), Lausanne, Switzerland
- Department of Radiology, Université de Lausanne (UNIL), Lausanne, Switzerland
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45
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Lanz B, Rackayova V, Braissant O, Cudalbu C. MRS studies of neuroenergetics and glutamate/glutamine exchange in rats: Extensions to hyperammonemic models. Anal Biochem 2017; 529:245-269. [DOI: 10.1016/j.ab.2016.11.021] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2016] [Revised: 11/16/2016] [Accepted: 11/30/2016] [Indexed: 01/27/2023]
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46
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Salzillo TC, Hu J, Nguyen L, Whiting N, Lee J, Weygand J, Dutta P, Pudakalakatti S, Millward NZ, Gammon ST, Lang FF, Heimberger AB, Bhattacharya PK. Interrogating Metabolism in Brain Cancer. Magn Reson Imaging Clin N Am 2017; 24:687-703. [PMID: 27742110 DOI: 10.1016/j.mric.2016.07.003] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
This article reviews existing and emerging techniques of interrogating metabolism in brain cancer from well-established proton magnetic resonance spectroscopy to the promising hyperpolarized metabolic imaging and chemical exchange saturation transfer and emerging techniques of imaging inflammation. Some of these techniques are at an early stage of development and clinical trials are in progress in patients to establish the clinical efficacy. It is likely that in vivo metabolomics and metabolic imaging is the next frontier in brain cancer diagnosis and assessing therapeutic efficacy; with the combined knowledge of genomics and proteomics a complete understanding of tumorigenesis in brain might be achieved.
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Affiliation(s)
- Travis C Salzillo
- Department of Cancer Systems Imaging, MD Anderson Cancer Center, The University of Texas, Houston, TX, USA; The University of Texas Health Science Center at Houston, Houston, TX, USA
| | - Jingzhe Hu
- Department of Cancer Systems Imaging, MD Anderson Cancer Center, The University of Texas, Houston, TX, USA; Department of Bioengineering, Rice University, Houston, TX, USA
| | - Linda Nguyen
- The University of Texas Health Science Center at Houston, Houston, TX, USA
| | - Nicholas Whiting
- Department of Cancer Systems Imaging, MD Anderson Cancer Center, The University of Texas, Houston, TX, USA
| | - Jaehyuk Lee
- Department of Cancer Systems Imaging, MD Anderson Cancer Center, The University of Texas, Houston, TX, USA
| | - Joseph Weygand
- Department of Cancer Systems Imaging, MD Anderson Cancer Center, The University of Texas, Houston, TX, USA; The University of Texas Health Science Center at Houston, Houston, TX, USA
| | - Prasanta Dutta
- Department of Cancer Systems Imaging, MD Anderson Cancer Center, The University of Texas, Houston, TX, USA
| | - Shivanand Pudakalakatti
- Department of Cancer Systems Imaging, MD Anderson Cancer Center, The University of Texas, Houston, TX, USA
| | - Niki Zacharias Millward
- Department of Cancer Systems Imaging, MD Anderson Cancer Center, The University of Texas, Houston, TX, USA
| | - Seth T Gammon
- Department of Cancer Systems Imaging, MD Anderson Cancer Center, The University of Texas, Houston, TX, USA
| | - Frederick F Lang
- Department of Neurosurgery, MD Anderson Cancer Center, The University of Texas, Houston, TX, USA
| | - Amy B Heimberger
- Department of Neurosurgery, MD Anderson Cancer Center, The University of Texas, Houston, TX, USA
| | - Pratip K Bhattacharya
- Department of Cancer Systems Imaging, MD Anderson Cancer Center, The University of Texas, Houston, TX, USA; The University of Texas Health Science Center at Houston, Houston, TX, USA.
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47
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Hu J, Lin S, Zheng B, Cheung PCK. Short-chain fatty acids in control of energy metabolism. Crit Rev Food Sci Nutr 2017; 58:1243-1249. [PMID: 27786539 DOI: 10.1080/10408398.2016.1245650] [Citation(s) in RCA: 244] [Impact Index Per Article: 34.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Short-chain fatty acids (SCFAs), especially acetate, propionate and butyrate, are the end products from the intestinal microbial fermentation of dietary fibers and resistant starch. It has been well documented that plasma and colonic SCFAs are associated with metabolic syndromes. Recently, the involvement of SCFAs in energy homeostasis regulation has been extensively studied. The importance of SCFAs on energy metabolism has highlighted the potential of modulating SCFAs as a nutritional target to prevent and counteract metabolism disorders and its associated diseases such as obesity and type 2 diabetes. Here, we summarize the current knowledge about the biological properties of SCFAs with their impact on the energy homeostasis.
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Affiliation(s)
- Jiamiao Hu
- a College of Food Science , Fujian Agriculture and Forestry University , Fuzhou , Fujian , P.R. China.,b Translational & Experimental Medicine, Division of Biomedical Sciences, Warwick Medical School , University of Warwick , Coventry , UK
| | - Shaoling Lin
- a College of Food Science , Fujian Agriculture and Forestry University , Fuzhou , Fujian , P.R. China
| | - Baodong Zheng
- a College of Food Science , Fujian Agriculture and Forestry University , Fuzhou , Fujian , P.R. China
| | - Peter C K Cheung
- c School of Life Sciences , The Chinese University of Hong Kong , Shatin, New Territories , Hong Kong SAR
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48
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L-Carnitine and Acetyl-L-carnitine Roles and Neuroprotection in Developing Brain. Neurochem Res 2017; 42:1661-1675. [PMID: 28508995 DOI: 10.1007/s11064-017-2288-7] [Citation(s) in RCA: 160] [Impact Index Per Article: 22.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2017] [Revised: 04/27/2017] [Accepted: 04/28/2017] [Indexed: 12/30/2022]
Abstract
L-Carnitine functions to transport long chain fatty acyl-CoAs into the mitochondria for degradation by β-oxidation. Treatment with L-carnitine can ameliorate metabolic imbalances in many inborn errors of metabolism. In recent years there has been considerable interest in the therapeutic potential of L-carnitine and its acetylated derivative acetyl-L-carnitine (ALCAR) for neuroprotection in a number of disorders including hypoxia-ischemia, traumatic brain injury, Alzheimer's disease and in conditions leading to central or peripheral nervous system injury. There is compelling evidence from preclinical studies that L-carnitine and ALCAR can improve energy status, decrease oxidative stress and prevent subsequent cell death in models of adult, neonatal and pediatric brain injury. ALCAR can provide an acetyl moiety that can be oxidized for energy, used as a precursor for acetylcholine, or incorporated into glutamate, glutamine and GABA, or into lipids for myelination and cell growth. Administration of ALCAR after brain injury in rat pups improved long-term functional outcomes, including memory. Additional studies are needed to better explore the potential of L-carnitine and ALCAR for protection of developing brain as there is an urgent need for therapies that can improve outcome after neonatal and pediatric brain injury.
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49
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Spick C, Herrmann K, Czernin J. Evaluation of Prostate Cancer with 11C-Acetate PET/CT. J Nucl Med 2017; 57:30S-37S. [PMID: 27694168 DOI: 10.2967/jnumed.115.169599] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2016] [Accepted: 03/10/2016] [Indexed: 11/16/2022] Open
Abstract
In this article, we will first describe the metabolic fate of 11C-acetate; then discuss its biodistribution in health and disease; and subsequently focus on its key clinical applications, the detection and localization of prostate cancer tissue in patients with primary or recurrent disease. Finally, we will discuss the potential role of 11C-acetate in the context of other prostate cancer imaging probes and non-radionuclide-based imaging approaches.
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Affiliation(s)
- Claudio Spick
- Ahmanson Translational Imaging Division, Department of Molecular and Medical Pharmacology, David Geffen School of Medicine at UCLA, Los Angeles, California
| | - Ken Herrmann
- Ahmanson Translational Imaging Division, Department of Molecular and Medical Pharmacology, David Geffen School of Medicine at UCLA, Los Angeles, California
| | - Johannes Czernin
- Ahmanson Translational Imaging Division, Department of Molecular and Medical Pharmacology, David Geffen School of Medicine at UCLA, Los Angeles, California
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50
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Witt AM, Larsen FS, Bjerring PN. Accumulation of lactate in the rat brain during hyperammonaemia is not associated with impaired mitochondrial respiratory capacity. Metab Brain Dis 2017; 32:461-470. [PMID: 27928693 DOI: 10.1007/s11011-016-9934-7] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/18/2016] [Accepted: 11/29/2016] [Indexed: 01/27/2023]
Abstract
In acute liver failure (ALF) cerebral oedema and high intracranial pressure (ICP) are potentially deadly complications. Astrocytes cultured in ammonia have shown mitochondrial dysfunction and in rat models of liver failure, de novo lactate production in the brain has been observed and has led to a hypothesis of compromised brain metabolism during ALF. In contrast, normal lactate levels are found in cerebral microdialysate of ALF patients and the oxygen: glucose ratio of cerebral metabolic rates remains normal. To investigate this inconsistency we studied the mitochondrial function in brain tissue with respirometry in animal models of hyperammonaemia. Wistar rats with systemic inflammation induced by lipopolysaccharide or liver insufficiency induced by 90% hepatectomy were given ammonium or sodium acetate for 120 min. A cerebral cortex homogenate was studied with respirometry and substrates of the citric acid cycle, uncouplers and inhibitors of the mitochondrial complexes were successively added to investigate the mitochondrial function in detail. In a separate dose-response experiment cortex from healthy rats was incubated for 120 min in ammonium acetate in concentrations up to 80 mM prior to respirometry. Hyperammonaemia was associated with elevated ICP and increased tissue lactate concentration. No difference between groups was found in total respiratory capacity or the function of individual mitochondrial complexes. Ammonium in concentrations of 40 and 80 mM reduced the respiratory capacity in vitro. In conclusion, acute hyperammonaemia leads to elevated ICP and cerebral lactate accumulation. We found no indications of impaired oxidative metabolism in vivo but only in vitro at extreme concentrations of ammonium.
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Affiliation(s)
- Anne Møller Witt
- Department of Hepatology, Rigshospitalet, DK-2100, Copenhagen, Denmark
| | - Fin Stolze Larsen
- Department of Hepatology, Rigshospitalet, DK-2100, Copenhagen, Denmark
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