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Furukawa T, Fukuda A. Maternal taurine as a modulator of Cl - homeostasis as well as of glycine/GABA A receptors for neocortical development. Front Cell Neurosci 2023; 17:1221441. [PMID: 37601283 PMCID: PMC10435090 DOI: 10.3389/fncel.2023.1221441] [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: 05/12/2023] [Accepted: 07/20/2023] [Indexed: 08/22/2023] Open
Abstract
During brain and spinal cord development, GABA and glycine, the inhibitory neurotransmitters, cause depolarization instead of hyperpolarization in adults. Since glycine and GABAA receptors (GABAARs) are chloride (Cl-) ion channel receptor, the conversion of GABA/glycine actions during development is influenced by changes in the transmembrane Cl- gradient, which is regulated by Cl- transporters, NKCC1 (absorption) and KCC2 (expulsion). In immature neurons, inhibitory neurotransmitters are released in a non-vesicular/non-synaptic manner, transitioning to vesicular/synaptic release as the neuron matures. In other word, in immature neurons, neurotransmitters generally act tonically. Thus, the glycine/GABA system is a developmentally multimodal system that is required for neurogenesis, differentiation, migration, and synaptogenesis. The endogenous agonists for these receptors are not fully understood, we address taurine. In this review, we will discuss about the properties and function of taurine during development of neocortex. Taurine cannot be synthesized by fetuses or neonates, and is transferred from maternal blood through the placenta or maternal milk ingestion. In developing neocortex, taurine level is higher than GABA level, and taurine tonically activates GABAARs to control radial migration as a stop signal. In the marginal zone (MZ) of the developing neocortex, endogenous taurine modulates the spread of excitatory synaptic transmission, activating glycine receptors (GlyRs) as an endogenous agonist. Thus, taurine affects information processing and crucial developmental processes such as axonal growth, cell migration, and lamination in the developing cerebral cortex. Additionally, we also refer to the possible mechanism of taurine-regulating Cl- homeostasis. External taurine is uptake by taurine transporter (TauT) and regulates NKCC1 and KCC2 mediated by intracellular signaling pathway, with-no-lysine kinase 1 (WNK1) and its subsequent kinases STE20/SPS1-related proline-alanine-rich protein kinase (SPAK) and oxidative stress response kinase-1 (OSR1). Through the regulation of NKCC1 and KCC2, mediated by the WNK-SPAK/OSR1 signaling pathway, taurine plays a role in maintaining Cl- homeostasis during normal brain development.
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Affiliation(s)
- Tomonori Furukawa
- Department of Neurophysiology, Hirosaki University Graduate School of Medicine, Hirosaki, Japan
| | - Atsuo Fukuda
- Department of Neurophysiology, Hamamatsu University School of Medicine, Hamamatsu, Japan
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Oyovwi MO, Nwangwa EK, Ben-Azu B, Edesiri TP, Emojevwe V, Igweh JC. Taurine and coenzyme Q10 synergistically prevent and reverse chlorpromazine-induced psycho-neuroendocrine changes and cataleptic behavior in rats. NAUNYN-SCHMIEDEBERG'S ARCHIVES OF PHARMACOLOGY 2021; 394:717-734. [PMID: 33146779 DOI: 10.1007/s00210-020-02003-z] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/02/2020] [Accepted: 10/15/2020] [Indexed: 12/21/2022]
Abstract
Over the years, mounting evidences have suggested a strong association between chronic chlorpromazine therapy, a popular first-generation antipsychotic drug, and psycho-neuroendocrine changes. In this study, we aim to examine whether treatment with taurine and coenzyme Q10 (COQ-10), compounds with steroidogenic-gonadotropin hormone-enhancing properties, can attenuate the negative impacts of chlorpromazine on steroidogenic, gonadotropin, thyroid and HPA-axis hormones, dopamine levels, catalepsy behavior and neuronal cells of the hypothalamus and pituitary gland in the preventive and reversal treatments in male Wister rats. In the drug treatment alone or preventive protocol, rats received oral administration of saline (10 mL/kg), taurine (150 mg/kg/day), COQ-10 (10 mg/kg/day), or both (taurine + COQ-10/day) alone for 56 consecutive days, or in combination with oral chlorpromazine (30 mg/kg/day) treatment from days 29 to 56. In the reversal protocol, the animals received chlorpromazine or saline for 56 days prior to taurine, COQ-10, or the combination from days 29 to 56. Thereafter, serum prolactin, steroidogenic (testosterone, estrogen, progesterone), gonadotropin (luteinizing hormone, LH, follicle-stimulating hormone, FSH), thyroid (thyrotropin-stimulating hormone, tetraiodothyronine, triiodothyronine) hormones, corticosterone, brain dopamine levels and cataleptic behavior were investigated. The histopathological features of the hypothalamus and pituitary gland were also evaluated. Taurine, COQ-10, or their combination prevented and reversed chlorpromazine-induced hyperprolactinemia, decrease in FSH, LH, testosterone, progesterone and dopamine concentrations, as well as the increase in estrogen levels. Taurine and COQ-10 reduced the changes in thyroid hormones, corticosterone release, histological distortions of the hypothalamus and the pituitary gland of chlorpromazine-treated rats. Taurine and COQ-10 attenuated chlorpromazine-induced catalepsy. The study showed that taurine and COQ-10 prevented and reversed chlorpromazine-induced changes in reproductive, thyroid hormones, dopamine level, corticosterone release, neurodegenerations, and cataleptic behavior in rats.
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Affiliation(s)
- Mega O Oyovwi
- Department of Human Physiology, Faculty of Basic Medical Sciences, Delta State University, Abraka, Delta State, Nigeria
- Department of Basic Medical Science, Achievers University, Owo, Ondo State, Nigeria
| | - Eze K Nwangwa
- Department of Human Physiology, Faculty of Basic Medical Sciences, Delta State University, Abraka, Delta State, Nigeria
| | - Benneth Ben-Azu
- Department of Pharmacology, Faculty of Basic Medical Science, PAMO University of Medical Sciences, Port Harcourt, Rivers State, Nigeria.
| | - Tesi P Edesiri
- Department of Science Laboratory Technology, Delta State Polytechnic, Ogwashi-Uku, Delta State, Nigeria
| | - Victor Emojevwe
- Department of Physiology, Faculty of Baic Medical Sciences, University of Medical Sciences, Ondo, Ondo State, Nigeria
| | - John C Igweh
- Department of Human Physiology, Faculty of Basic Medical Sciences, Delta State University, Abraka, Delta State, Nigeria
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Dalangin R, Kim A, Campbell RE. The Role of Amino Acids in Neurotransmission and Fluorescent Tools for Their Detection. Int J Mol Sci 2020; 21:E6197. [PMID: 32867295 PMCID: PMC7503967 DOI: 10.3390/ijms21176197] [Citation(s) in RCA: 64] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2020] [Revised: 08/17/2020] [Accepted: 08/24/2020] [Indexed: 12/20/2022] Open
Abstract
Neurotransmission between neurons, which can occur over the span of a few milliseconds, relies on the controlled release of small molecule neurotransmitters, many of which are amino acids. Fluorescence imaging provides the necessary speed to follow these events and has emerged as a powerful technique for investigating neurotransmission. In this review, we highlight some of the roles of the 20 canonical amino acids, GABA and β-alanine in neurotransmission. We also discuss available fluorescence-based probes for amino acids that have been shown to be compatible for live cell imaging, namely those based on synthetic dyes, nanostructures (quantum dots and nanotubes), and genetically encoded components. We aim to provide tool developers with information that may guide future engineering efforts and tool users with information regarding existing indicators to facilitate studies of amino acid dynamics.
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Affiliation(s)
- Rochelin Dalangin
- Department of Chemistry, University of Alberta, Edmonton, AB T6G 2G2, Canada; (R.D.); (A.K.)
| | - Anna Kim
- Department of Chemistry, University of Alberta, Edmonton, AB T6G 2G2, Canada; (R.D.); (A.K.)
| | - Robert E. Campbell
- Department of Chemistry, University of Alberta, Edmonton, AB T6G 2G2, Canada; (R.D.); (A.K.)
- Department of Chemistry, Graduate School of Science, The University of Tokyo, Bunkyo City, Tokyo 113-0033, Japan
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Luengo JG, Muñoz MD, Álvarez-Merz I, Herranz AS, González JC, Martín del Río R, Hernández-Guijo JM, Solís JM. Intracellular accumulation of amino acids increases synaptic potentials in rat hippocampal slices. Amino Acids 2019; 51:1337-1351. [DOI: 10.1007/s00726-019-02771-w] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2018] [Accepted: 08/11/2019] [Indexed: 12/22/2022]
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Kim YH, Shim HS, Kim KH, Lee J, Chung BC, Kowall NW, Ryu H, Lee J. Metabolomic Analysis Identifies Alterations of Amino Acid Metabolome Signatures in the Postmortem Brain of Alzheimer's Disease. Exp Neurobiol 2019; 28:376-389. [PMID: 31308797 PMCID: PMC6614073 DOI: 10.5607/en.2019.28.3.376] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/01/2019] [Revised: 05/19/2019] [Accepted: 05/21/2019] [Indexed: 02/06/2023] Open
Abstract
Despite significant advances in neuroscience research over the past several decades, the exact cause of AD has not yet fully understood. The metabolic hypothesis as well as the amyloid and tau hypotheses have been proposed to be associated with AD pathogenesis. In order to identify metabolome signatures from the postmortem brains of sporadic AD patients and control subjects, we performed ultra performance liquid chromatography coupled with linear ion trap-Orbitrap mass spectrometer (UPLC-LTQ-Orbitrap-MS). Not only our study identified new metabolome signatures but also verified previously known metabolome profiles in the brain. Statistical modeling of the analytical data and validation of the structural assignments discovered metabolic biomarkers associated with the AD pathogenesis. Interestingly, hypotaurin, myo-inositol and oxo-proline levels were markedly elevated in AD while lutamate and N-acetyl-aspartate were decreased in the postmortem brain tissue of AD patients. In addition, neurosteroid level such as cortisol was significantly increased in AD. Together, our data indicate that impaired amino acid metabolism is associated with AD pathogenesis and the altered amino acid signatures can be useful diagnostic biomarkers of AD. Thus, modulation of amino acid metabolism may be a possible therapeutic approach to treat AD.
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Affiliation(s)
- Yoon Hwan Kim
- MolecularRecognition Research Center, Korea Institute of Science and Technology, Seoul 02792, Korea
- Department of Biotechnology, Graduate School, Korea University, Seoul 02792, Korea
| | - Hyun Soo Shim
- Center for Neuroscience, Brain Science Institute, Korea Institute of Science and Technology, Seoul 02792, Korea
| | - Kyoung Heon Kim
- Department of Biotechnology, Graduate School, Korea University, Seoul 02792, Korea
| | - Junghee Lee
- Veteran's Affairs Boston Healthcare System, Boston, MA 02130, USA
- Boston University Alzheimer's Disease Center and Department of Neurology, Boston University School of Medicine, Boston, MA 02118, USA
| | - Bong Chul Chung
- MolecularRecognition Research Center, Korea Institute of Science and Technology, Seoul 02792, Korea
| | - Neil W. Kowall
- Veteran's Affairs Boston Healthcare System, Boston, MA 02130, USA
- Boston University Alzheimer's Disease Center and Department of Neurology, Boston University School of Medicine, Boston, MA 02118, USA
| | - Hoon Ryu
- Center for Neuroscience, Brain Science Institute, Korea Institute of Science and Technology, Seoul 02792, Korea
- Veteran's Affairs Boston Healthcare System, Boston, MA 02130, USA
- Boston University Alzheimer's Disease Center and Department of Neurology, Boston University School of Medicine, Boston, MA 02118, USA
- Convergence Research Center for Diagnosis, Treatment and Care System of Dementia, Korea Institute of Science and Technology, Seoul 02792, Korea
| | - Jeongae Lee
- MolecularRecognition Research Center, Korea Institute of Science and Technology, Seoul 02792, Korea
- Convergence Research Center for Diagnosis, Treatment and Care System of Dementia, Korea Institute of Science and Technology, Seoul 02792, Korea
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Liberato JL, Godoy LD, Cunha AOS, Mortari MR, de Oliveira Beleboni R, Fontana ACK, Lopes NP, Dos Santos WF. Parawixin2 Protects Hippocampal Cells in Experimental Temporal Lobe Epilepsy. Toxins (Basel) 2018; 10:toxins10120486. [PMID: 30469496 PMCID: PMC6316435 DOI: 10.3390/toxins10120486] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2018] [Revised: 10/27/2018] [Accepted: 11/13/2018] [Indexed: 12/20/2022] Open
Abstract
Epilepsy is considered as one of the major disabling neuropathologies. Almost one third of adult patients with temporal lobe epilepsy (TLE) do not respond to current antiepileptic drugs (AEDs). Additionally, most AEDs do not have neuroprotective effects against the inherent neurodegenerative process underlying the hippocampal sclerosis on TLE. Dysfunctions in the GABAergic neurotransmission may contribute not only to the onset of epileptic activity but also constitute an important system for therapeutic approaches. Therefore, molecules that enhance GABA inhibitory effects could open novel avenues for the understanding of epileptic plasticity and for drug development. Parawixin2, a compound isolated from Parawixia bistriata spider venom, inhibits both GABA and glycine uptake and has an anticonvulsant effect against a wide range of chemoconvulsants. The neuroprotective potential of Parawixin2 was analyzed in a model of TLE induced by a long-lasting Status Epilepticus (SE), and its efficiency was compared to well-known neuroprotective drugs, such as riluzole and nipecotic acid. Neuroprotection was assessed through histological markers for cell density (Nissl), astrocytic reactivity (GFAP) and cell death labeling (TUNEL), which were performed 24 h and 72 h after SE. Parawixin2 treatment resulted in neuroprotective effects in a dose dependent manner at 24 h and 72 h after SE, as well as reduced reactive astrocytes and apoptotic cell death. Based on these findings, Parawixin2 has a great potential to be used as a tool for neuroscience research and as a probe to the development of novel GABAergic neuroprotective agents.
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Affiliation(s)
- José Luiz Liberato
- Neurobiology and Venoms Laboratory (LNP), Department of Biology, College of Philosophy, Sciences and Literature of Ribeirão Preto, University of São Paulo, Av. Bandeirantes, 3900, Ribeirão Preto, 14040-901 São Paulo, Brazil.
- Neuroscience Behavioral Institute (INEC), Av. do Café, 2450, Ribeirão Preto, 14050-220 São Paulo, Brazil.
| | - Lívea Dornela Godoy
- Neurobiology and Venoms Laboratory (LNP), Department of Biology, College of Philosophy, Sciences and Literature of Ribeirão Preto, University of São Paulo, Av. Bandeirantes, 3900, Ribeirão Preto, 14040-901 São Paulo, Brazil.
- Neuroscience Behavioral Institute (INEC), Av. do Café, 2450, Ribeirão Preto, 14050-220 São Paulo, Brazil.
| | - Alexandra Olimpio Siqueira Cunha
- Neurobiology and Venoms Laboratory (LNP), Department of Biology, College of Philosophy, Sciences and Literature of Ribeirão Preto, University of São Paulo, Av. Bandeirantes, 3900, Ribeirão Preto, 14040-901 São Paulo, Brazil.
| | - Marcia Renata Mortari
- Laboratory of Neuropharmacology, Department of Physiological Sciences, Institute of Biological Sciences, University of Brasília, DF 70910-900 Brasília, Brazil.
| | - Rene de Oliveira Beleboni
- Department of Biotechnology/School of Medicine, University of Ribeirão Preto, Av. Costábile Romano, 2201, Ribeirão Preto, 14096-900 São Paulo, Brazil.
| | - Andréia C K Fontana
- Department of Pharmacology and Physiology, Drexel University College of Medicine, 245 N. 15th Street, Philadelphia, PA 19102, USA.
| | - Norberto Peporine Lopes
- NPPNS, Department of Physics and Chemistry, College of Pharmaceutical Sciences of Ribeirão Preto, University of São Paulo, Ribeirão Preto, SP, Brazil, Av. do Cafe s/n, Ribeirão Preto, 14040-903 São Paulo, Brazil.
| | - Wagner Ferreira Dos Santos
- Neurobiology and Venoms Laboratory (LNP), Department of Biology, College of Philosophy, Sciences and Literature of Ribeirão Preto, University of São Paulo, Av. Bandeirantes, 3900, Ribeirão Preto, 14040-901 São Paulo, Brazil.
- Neuroscience Behavioral Institute (INEC), Av. do Café, 2450, Ribeirão Preto, 14050-220 São Paulo, Brazil.
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Niu X, Zheng S, Liu H, Li S. Protective effects of taurine against inflammation, apoptosis, and oxidative stress in brain injury. Mol Med Rep 2018; 18:4516-4522. [PMID: 30221665 PMCID: PMC6172387 DOI: 10.3892/mmr.2018.9465] [Citation(s) in RCA: 45] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2018] [Accepted: 08/28/2018] [Indexed: 12/14/2022] Open
Abstract
The protective effect of taurine against inflammation, apoptosis and oxidative stress in traumatic brain injury was investigated in the present study. Taurine is a non-proteogenic and essential amino acid in animals. It plays a critical nutritional role in brain cell growth, differentiation, and development. Taurine is involved in regeneration and neuroprotection in the injured nervous system, and is an effective antioxidant against lead-, cadmium-, and exercise-induced oxidative stress. Astrocytes and neuron cells were co-cultured and cells were treated with different concentrations of taurine (100, 200 and 300 mg/l) for 72 h, and the levels of reactive oxygen species, malondialdehyde, reduced glutathione, glutathione peroxidase, superoxide dismutase, catalase, acetylcholinesterase, tumor necrosis factor-α, interleukin-6, caspase-3, p53, B-cell lymphoma 2 and Bcl-2-associated X protein were determined. These inflammatory, apoptotic, and oxidative stress markers were substantially increased in injured cells, and returned to normal levels following taurine supplementation. Thus, taurine supplementation may be effective against oxidative stress, apoptosis, and inflammation in injured brain cells.
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Affiliation(s)
- Xiaoli Niu
- Department of Anesthesiology, The Second Affiliated Hospital of Xi'an Jiaotong University, Xi'an, Shaanxi 710004, P.R. China
| | - Simin Zheng
- Department of Anesthesiology, The Second Affiliated Hospital of Xi'an Jiaotong University, Xi'an, Shaanxi 710004, P.R. China
| | - Hongtao Liu
- Department of Anesthesiology, The Second Affiliated Hospital of Xi'an Jiaotong University, Xi'an, Shaanxi 710004, P.R. China
| | - Siyuan Li
- Department of Anesthesiology, The Second Affiliated Hospital of Xi'an Jiaotong University, Xi'an, Shaanxi 710004, P.R. China
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Rossi F, Geiszler PC, Meng W, Barron MR, Prior M, Herd-Smith A, Loreto A, Lopez MY, Faas H, Pardon MC, Conforti L. NAD-biosynthetic enzyme NMNAT1 reduces early behavioral impairment in the htau mouse model of tauopathy. Behav Brain Res 2018; 339:140-152. [PMID: 29175372 PMCID: PMC5769520 DOI: 10.1016/j.bbr.2017.11.030] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2017] [Revised: 11/08/2017] [Accepted: 11/22/2017] [Indexed: 11/04/2022]
Abstract
NAD metabolism and the NAD biosynthetic enzymes nicotinamide nucleotide adenylyltransferases (NMNATs) are thought to play a key neuroprotective role in tauopathies, including Alzheimer's disease. Here, we investigated whether modulating the expression of the NMNAT nuclear isoform NMNAT1, which is important for neuronal maintenance, influences the development of behavioral and neuropathological abnormalities in htau mice, which express non-mutant human tau isoforms and represent a model of tauopathy relevant to Alzheimer's disease. Prior to the development of cognitive symptoms, htau mice exhibit tau hyperphosphorylation associated with a selective deficit in food burrowing, a behavior reminiscent to activities of daily living which are impaired early in Alzheimer's disease. We crossed htau mice with Nmnat1 transgenic and knockout mice and tested the resulting offspring until the age of 6 months. We show that overexpression of NMNAT1 ameliorates the early deficit in food burrowing characteristic of htau mice. At 6 months of age, htau mice did not show neurodegenerative changes in both the cortex and hippocampus, and these were not induced by downregulating NMNAT1 levels. Modulating NMNAT1 levels produced a corresponding effect on NMNAT enzymatic activity but did not alter NAD levels in htau mice. Although changes in local NAD levels and subsequent modulation of NAD-dependent enzymes cannot be ruled out, this suggests that the effects seen on behavior may be due to changes in tau phosphorylation. Our results suggest that increasing NMNAT1 levels can slow the progression of symptoms and neuropathological features of tauopathy, but the underlying mechanisms remain to be established.
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Affiliation(s)
- Francesca Rossi
- School of Life Sciences, University of Nottingham, Queen's Medical Centre Medical School, Nottingham, NG7 2UH, UK; Department of Biomedical Sciences, Cagliari University, Cagliari 09042, Italy
| | - Philippine C Geiszler
- School of Life Sciences, University of Nottingham, Queen's Medical Centre Medical School, Nottingham, NG7 2UH, UK
| | - Weina Meng
- School of Life Sciences, University of Nottingham, Queen's Medical Centre Medical School, Nottingham, NG7 2UH, UK
| | - Matthew R Barron
- School of Life Sciences, University of Nottingham, Queen's Medical Centre Medical School, Nottingham, NG7 2UH, UK
| | - Malcolm Prior
- Department of Biomedical Sciences, Cagliari University, Cagliari 09042, Italy
| | - Anna Herd-Smith
- School of Life Sciences, University of Nottingham, Queen's Medical Centre Medical School, Nottingham, NG7 2UH, UK
| | - Andrea Loreto
- School of Life Sciences, University of Nottingham, Queen's Medical Centre Medical School, Nottingham, NG7 2UH, UK
| | - Maria Yanez Lopez
- Sir Peter Mansfield Imaging Centre, School of Medicine, University of Nottingham, Queen's Medical Centre, Medical School, Nottingham NG7 2UH, UK; Faculty of Medicine, Department of Medicine, Imperial College London, Burlington Danes, Hammersmith campus, London W12 0NN, UK
| | - Henryk Faas
- Sir Peter Mansfield Imaging Centre, School of Medicine, University of Nottingham, Queen's Medical Centre, Medical School, Nottingham NG7 2UH, UK
| | - Marie-Christine Pardon
- School of Life Sciences, University of Nottingham, Queen's Medical Centre Medical School, Nottingham, NG7 2UH, UK.
| | - Laura Conforti
- School of Life Sciences, University of Nottingham, Queen's Medical Centre Medical School, Nottingham, NG7 2UH, UK
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Betaine in the Brain: Characterization of Betaine Uptake, its Influence on Other Osmolytes and its Potential Role in Neuroprotection from Osmotic Stress. Neurochem Res 2017; 42:3490-3503. [PMID: 28918494 DOI: 10.1007/s11064-017-2397-3] [Citation(s) in RCA: 49] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2017] [Revised: 07/15/2017] [Accepted: 08/29/2017] [Indexed: 01/17/2023]
Abstract
Betaine (N-trimethylglycine), a common osmolyte, has received attention because of the number of clinical reports associating betaine supplementation with improved cognition, neuroprotection and exercise physiology. However, tissue analyses report little accumulation of betaine in brain tissue despite the presence of betaine/GABA transporters (BGT1) at the blood brain barrier and in nervous tissue, calling into question whether betaine influences neuronal function directly or indirectly. Therefore, the focus of this study was to determine what capacity nervous tissue has to accumulate betaine, specifically in the hippocampus, a region of the brain associated with learning and memory and one that is particularly susceptible to damage (e.g., seizure activity). Here we report that hippocampal slices actively accumulate betaine in a time, dose and osmolality dependent manner, resulting in peak intracellular concentrations four times extracellular concentrations within 8 h. Our data also indicate that betaine uptake differentially influences the accumulation of other osmolytes. Under isosmotic conditions, betaine uptake minimally impacted some osmolytes (e.g., glycerylphosphorylcholine and glutamate) while significantly reducing others (taurine, creatine, and myo-inositol). Under osmotic stress (hyperosmotic) conditions, we observed dramatic changes in osmolytes like glycine and glutamine-key players in inhibitory neurotransmission-and little change in osmolytes such as taurine, creatine and myo-inositol when betaine was available. These data suggest that betaine may influence pathways of inhibitory neurotransmitter production/recycling in addition to serving as an osmolyte and metabolic intermediate. In sum, our data provide detailed characterization of betaine uptake in the hippocampus that implicates betaine in the modulation of hippocampal neurophysiology and neuroprotection.
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Zhang Y, Li D, Li H, Hou D, Hou J. Taurine Pretreatment Prevents Isoflurane-Induced Cognitive Impairment by Inhibiting ER Stress-Mediated Activation of Apoptosis Pathways in the Hippocampus in Aged Rats. Neurochem Res 2016; 41:2517-2525. [DOI: 10.1007/s11064-016-1963-4] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2016] [Revised: 05/01/2016] [Accepted: 05/24/2016] [Indexed: 11/30/2022]
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Shiohira S, Komatsu M, Okazaki M, Naganuma T, Kawaguchi H, Nitta K, Tsuchiya K. Effect of Taurine on Hemodiafiltration in Patients With Chronic Heart Failure. Ther Apher Dial 2015; 20:20-6. [PMID: 26712423 DOI: 10.1111/1744-9987.12330] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Taurine, an important factor in the living body, is essential for cardiovascular function and development and function of skeletal muscle, retina and central nervous system. In the present study, its effect on cardiovascular function was specifically taken into consideration. In hemodiafiltration (HDF) patients, the effect of taurine on patients with chronic heart failure (CHF), in whom dry weight was difficult to control, was evaluated. All patients who were subjected to regular HDF for 4 h three times per week at Joban hospital were included in this study. Patients with chronic heart failure, in whom dry weight was difficult to control (N = 4), were included in the evaluation of clinical status. X-ray and echocardiography were determined before and after taurine treatment. Almost all patients were taking nitric acid, warfarin, anti-platelet agents and vasopressors. Because vital signs were unstable in chronic heart failure, all cases withheld antihypertensive drugs during HDF. For unstable vital signs during HDF, pulmonary congestion was chronically recognized. After taurine was started, vital signs stabilized and lowering of dry weight was possible. In addition, X-ray and cardiac diastolic failure on echocardiography improved. Taurine was effective for CHF patients on HDF in whom dry weight was difficult to control in spite of various medications.
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Affiliation(s)
- Shunji Shiohira
- Department of Medicine IV, Tokyo Women's Medical University, Tokyo, Japan.,Department of Blood Purification, Joban Hospital, Fukushima, Japan
| | - Mizuki Komatsu
- Department of Blood Purification, Joban Hospital, Fukushima, Japan
| | - Masayuki Okazaki
- Department of Blood Purification, Joban Hospital, Fukushima, Japan
| | | | | | - Kosaku Nitta
- Department of Medicine IV, Tokyo Women's Medical University, Tokyo, Japan
| | - Ken Tsuchiya
- Department of Medicine IV, Tokyo Women's Medical University, Tokyo, Japan
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Villeneuve LM, Purnell PR, Boska MD, Fox HS. Early Expression of Parkinson's Disease-Related Mitochondrial Abnormalities in PINK1 Knockout Rats. Mol Neurobiol 2014; 53:171-186. [PMID: 25421206 DOI: 10.1007/s12035-014-8927-y] [Citation(s) in RCA: 60] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2014] [Accepted: 10/07/2014] [Indexed: 12/21/2022]
Abstract
PTEN-induced kinase 1 (PINK1) mutations are responsible for an autosomal recessive, familial form of Parkinson's disease. PINK1 protein is a Ser/Thr kinase localized to the mitochondrial membrane and is involved in many processes including mitochondrial trafficking, mitophagy, and proteasomal function. Using a new PINK1 knockout (PINK1 KO) rat model, we found altered brain metabolomic markers using magnetic resonance spectroscopy, identified changes in mitochondrial pathways with quantitative proteomics using sequential window acquisition of all theoretical spectra (SWATH) mass spectrometry, and demonstrated mitochondrial functional alterations through measurement of oxygen consumption and acidification rates. The observed alterations included reduced creatine, decreased levels of complex I of the electron transport chain, and increased proton leak in the electron transport chain in PINK1 KO rat brains. In conjunction, these results demonstrate metabolomic and mitochondrial alterations occur during the asymptomatic phase of Parkinson's disease in this model. These results indicate both potential early diagnostic markers and therapeutic pathways that can be used in PD.
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Affiliation(s)
- Lance M Villeneuve
- Department of Pharmacology and Experimental Neuroscience, University of Nebraska Medical Center, 985800 Nebraska Medical Center-DRC1 3008, Omaha, NE, 68198-5800, USA
| | - Phillip R Purnell
- Department of Pharmacology and Experimental Neuroscience, University of Nebraska Medical Center, 985800 Nebraska Medical Center-DRC1 3008, Omaha, NE, 68198-5800, USA
| | - Michael D Boska
- Department of Pharmacology and Experimental Neuroscience, University of Nebraska Medical Center, 985800 Nebraska Medical Center-DRC1 3008, Omaha, NE, 68198-5800, USA.,Department of Radiology, University of Nebraska Medical Center, Omaha, NE, 68198, USA
| | - Howard S Fox
- Department of Pharmacology and Experimental Neuroscience, University of Nebraska Medical Center, 985800 Nebraska Medical Center-DRC1 3008, Omaha, NE, 68198-5800, USA.
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13
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Suárez LM, Bustamante J, Orensanz LM, Martín del Río R, Solís JM. Cooperation of taurine uptake and dopamine D1 receptor activation facilitates the induction of protein synthesis-dependent late LTP. Neuropharmacology 2014; 79:101-11. [DOI: 10.1016/j.neuropharm.2013.10.035] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2013] [Revised: 10/28/2013] [Accepted: 10/30/2013] [Indexed: 01/07/2023]
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14
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Qian T, Chen R, Nakamura M, Furukawa T, Kumada T, Akita T, Kilb W, Luhmann HJ, Nakahara D, Fukuda A. Activity-dependent endogenous taurine release facilitates excitatory neurotransmission in the neocortical marginal zone of neonatal rats. Front Cell Neurosci 2014; 8:33. [PMID: 24574969 PMCID: PMC3918584 DOI: 10.3389/fncel.2014.00033] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2013] [Accepted: 01/22/2014] [Indexed: 12/27/2022] Open
Abstract
In the developing cerebral cortex, the marginal zone (MZ), consisting of early-generated neurons such as Cajal-Retzius cells, plays an important role in cell migration and lamination. There is accumulating evidence of widespread excitatory neurotransmission mediated by γ-aminobutyric acid (GABA) in the MZ. Cajal-Retzius cells express not only GABAA receptors but also α2/β subunits of glycine receptors, and exhibit glycine receptor-mediated depolarization due to high [Cl−]i. However, the physiological roles of glycine receptors and their endogenous agonists during neurotransmission in the MZ are yet to be elucidated. To address this question, we performed optical imaging from the MZ using the voltage-sensitive dye JPW1114 on tangential neocortical slices of neonatal rats. A single electrical stimulus evoked an action-potential-dependent optical signal that spread radially over the MZ. The amplitude of the signal was not affected by glutamate receptor blockers, but was suppressed by either GABAA or glycine receptor antagonists. Combined application of both antagonists nearly abolished the signal. Inhibition of Na+, K+-2Cl− cotransporter by 20 µM bumetanide reduced the signal, indicating that this transporter contributes to excitation. Analysis of the interstitial fluid obtained by microdialysis from tangential neocortical slices with high-performance liquid chromatography revealed that GABA and taurine, but not glycine or glutamate, were released in the MZ in response to the electrical stimulation. The ambient release of taurine was reduced by the addition of a voltage-sensitive Na+ channel blocker. Immunohistochemistry and immunoelectron microscopy indicated that taurine was stored both in Cajal-Retzius and non-Cajal-Retzius cells in the MZ, but was not localized in presynaptic structures. Our results suggest that activity-dependent non-synaptic release of endogenous taurine facilitates excitatory neurotransmission through activation of glycine receptors in the MZ.
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Affiliation(s)
- Taizhe Qian
- Department of Neurophysiology, Hamamatsu University School of Medicine Hamamatsu, Japan
| | - Rongqing Chen
- Institute of Physiology, University Medical Center of the Johannes Gutenberg-University Mainz, Germany
| | - Masato Nakamura
- Department of Psychology and Behavioral Neuroscience, Hamamatsu University School of Medicine Hamamatsu, Japan
| | - Tomonori Furukawa
- Department of Neurophysiology, Hamamatsu University School of Medicine Hamamatsu, Japan
| | - Tatsuro Kumada
- Department of Neurophysiology, Hamamatsu University School of Medicine Hamamatsu, Japan ; Department of Occupational Therapy, Tokoha University Hamamatsu, Japan
| | - Tenpei Akita
- Department of Neurophysiology, Hamamatsu University School of Medicine Hamamatsu, Japan
| | - Werner Kilb
- Institute of Physiology, University Medical Center of the Johannes Gutenberg-University Mainz, Germany
| | - Heiko J Luhmann
- Institute of Physiology, University Medical Center of the Johannes Gutenberg-University Mainz, Germany
| | - Daiichiro Nakahara
- Department of Psychology and Behavioral Neuroscience, Hamamatsu University School of Medicine Hamamatsu, Japan
| | - Atsuo Fukuda
- Department of Neurophysiology, Hamamatsu University School of Medicine Hamamatsu, Japan
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15
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Abstract
The mammalian genome contains four genes encoding GABA transporters (GAT1, slc6a1; GAT2, slc6a13; GAT3, slc6a11; BGT1, slc6a12) and five glutamate transporter genes (EAAT1, slc1a3; EAAT2, slc1a2; EAAT3, slc1a1; EAAT4, slc1a6; EAAT5, slc1a7). These transporters keep the extracellular levels of GABA and excitatory amino acids low and provide amino acids for metabolic purposes. The various transporters have different properties both with respect to their transport functions and with respect to their ability to act as ion channels. Further, they are differentially regulated. To understand the physiological roles of the individual transporter subtypes, it is necessary to obtain information on their distributions and expression levels. Quantitative data are important as the functional capacity is limited by the number of transporter molecules. The most important and most abundant transporters for removal of transmitter glutamate in the brain are EAAT2 (GLT-1) and EAAT1 (GLAST), while GAT1 and GAT3 are the major GABA transporters in the brain. EAAT3 (EAAC1) does not appear to play a role in signal transduction, but plays other roles. Due to their high uncoupled anion conductance, EAAT4 and EAAT5 seem to be acting more like inhibitory glutamate receptors than as glutamate transporters. GAT2 and BGT1 are primarily expressed in the liver and kidney, but are also found in the leptomeninges, while the levels in brain tissue proper are too low to have any impact on GABA removal, at least in normal young adult mice. The present review will provide summary of what is currently known and will also discuss some methodological pitfalls.
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Affiliation(s)
- Yun Zhou
- The Neurotransporter Group, Department of Anatomy, Institute of Basic Medical Sciences, University of Oslo, Oslo, Norway
| | - Niels Christian Danbolt
- The Neurotransporter Group, Department of Anatomy, Institute of Basic Medical Sciences, University of Oslo, Oslo, Norway
- *Correspondence: Niels Christian Danbolt, The Neurotransporter Group, Department of Anatomy, Institute of Basic Medical Sciences, University of Oslo, P.O. Box 1105 Blindern, Oslo N-0317, Norway e-mail:
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Zhou Y, Holmseth S, Guo C, Hassel B, Höfner G, Huitfeldt HS, Wanner KT, Danbolt NC. Deletion of the γ-aminobutyric acid transporter 2 (GAT2 and SLC6A13) gene in mice leads to changes in liver and brain taurine contents. J Biol Chem 2012; 287:35733-35746. [PMID: 22896705 DOI: 10.1074/jbc.m112.368175] [Citation(s) in RCA: 76] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Abstract
The GABA transporters (GAT1, GAT2, GAT3, and BGT1) have mostly been discussed in relation to their potential roles in controlling the action of transmitter GABA in the nervous system. We have generated the first mice lacking the GAT2 (slc6a13) gene. Deletion of GAT2 (both mRNA and protein) neither affected growth, fertility, nor life span under nonchallenging rearing conditions. Immunocytochemistry showed that the GAT2 protein was predominantly expressed in the plasma membranes of periportal hepatocytes and in the basolateral membranes of proximal tubules in the renal cortex. This was validated by processing tissue from wild-type and knockout mice in parallel. Deletion of GAT2 reduced liver taurine levels by 50%, without affecting the expression of the taurine transporter TAUT. These results suggest an important role for GAT2 in taurine uptake from portal blood into liver. In support of this notion, GAT2-transfected HEK293 cells transported [(3)H]taurine. Furthermore, most of the uptake of [(3)H]GABA by cultured rat hepatocytes was due to GAT2, and this uptake was inhibited by taurine. GAT2 was not detected in brain parenchyma proper, excluding a role in GABA inactivation. It was, however, expressed in the leptomeninges and in a subpopulation of brain blood vessels. Deletion of GAT2 increased brain taurine levels by 20%, suggesting a taurine-exporting role for GAT2 in the brain.
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Affiliation(s)
- Yun Zhou
- Centre of Molecular Biology and Neuroscience, Department of Anatomy, Institute of Basic Medical Sciences, University of Oslo, N-0317 Oslo, Norway
| | - Silvia Holmseth
- Centre of Molecular Biology and Neuroscience, Department of Anatomy, Institute of Basic Medical Sciences, University of Oslo, N-0317 Oslo, Norway
| | - Caiying Guo
- HHMI, Janelia Farm Research Campus, Ashburn, Virginia 20147
| | - Bjørnar Hassel
- Department for Neurohabilitation, Oslo University Hospital, N-0372 Oslo, Norway; Norwegian Defense Research Establishment, N-2027 Kjeller, Norway
| | - Georg Höfner
- Department für Pharmazie, Zentrum für Pharmaforschung, Ludwig-Maximilians-Universität München, D-81377 München, Germany
| | - Henrik S Huitfeldt
- Department of Pathology, Oslo University Hospital, University of Oslo, N-0372 Oslo, Norway
| | - Klaus T Wanner
- Department für Pharmazie, Zentrum für Pharmaforschung, Ludwig-Maximilians-Universität München, D-81377 München, Germany
| | - Niels C Danbolt
- Centre of Molecular Biology and Neuroscience, Department of Anatomy, Institute of Basic Medical Sciences, University of Oslo, N-0317 Oslo, Norway.
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Inoue K, Furukawa T, Kumada T, Yamada J, Wang T, Inoue R, Fukuda A. Taurine inhibits K+-Cl- cotransporter KCC2 to regulate embryonic Cl- homeostasis via with-no-lysine (WNK) protein kinase signaling pathway. J Biol Chem 2012; 287:20839-50. [PMID: 22544747 PMCID: PMC3375508 DOI: 10.1074/jbc.m111.319418] [Citation(s) in RCA: 72] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2011] [Revised: 04/02/2012] [Indexed: 01/01/2023] Open
Abstract
GABA inhibits mature neurons and conversely excites immature neurons due to lower K(+)-Cl(-) cotransporter 2 (KCC2) expression. We observed that ectopically expressed KCC2 in embryonic cerebral cortices was not active; however, KCC2 functioned in newborns. In vitro studies revealed that taurine increased KCC2 inactivation in a phosphorylation-dependent manner. When Thr-906 and Thr-1007 residues in KCC2 were substituted with Ala (KCC2T906A/T1007A), KCC2 activity was facilitated, and the inhibitory effect of taurine was not observed. Exogenous taurine activated the with-no-lysine protein kinase 1 (WNK1) and downstream STE20/SPS1-related proline/alanine-rich kinase (SPAK)/oxidative stress response 1 (OSR1), and overexpression of active WNK1 resulted in KCC2 inhibition in the absence of taurine. Phosphorylation of SPAK was consistently higher in embryonic brains compared with that of neonatal brains and down-regulated by a taurine transporter inhibitor in vivo. Furthermore, cerebral radial migration was perturbed by a taurine-insensitive form of KCC2, KCC2T906A/T1007A, which may be regulated by WNK-SPAK/OSR1 signaling. Thus, taurine and WNK-SPAK/OSR1 signaling may contribute to embryonic neuronal Cl(-) homeostasis, which is required for normal brain development.
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Affiliation(s)
- Koichi Inoue
- From the Department of Physiology, Hamamatsu University School of Medicine, 1-20-1 Handayama, Higashi-ku, Hamamatsu, Shizuoka 431-3192, Japan and
| | - Tomonori Furukawa
- From the Department of Physiology, Hamamatsu University School of Medicine, 1-20-1 Handayama, Higashi-ku, Hamamatsu, Shizuoka 431-3192, Japan and
| | - Tatsuro Kumada
- From the Department of Physiology, Hamamatsu University School of Medicine, 1-20-1 Handayama, Higashi-ku, Hamamatsu, Shizuoka 431-3192, Japan and
| | - Junko Yamada
- the Department of Neurophysiology, Hirosaki University Graduate School of Medicine, Hirosaki, Aomori 036-8562, Japan
| | - Tianying Wang
- From the Department of Physiology, Hamamatsu University School of Medicine, 1-20-1 Handayama, Higashi-ku, Hamamatsu, Shizuoka 431-3192, Japan and
| | - Rieko Inoue
- From the Department of Physiology, Hamamatsu University School of Medicine, 1-20-1 Handayama, Higashi-ku, Hamamatsu, Shizuoka 431-3192, Japan and
| | - Atsuo Fukuda
- From the Department of Physiology, Hamamatsu University School of Medicine, 1-20-1 Handayama, Higashi-ku, Hamamatsu, Shizuoka 431-3192, Japan and
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18
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Tachikawa M, Hosoya KI. Transport characteristics of guanidino compounds at the blood-brain barrier and blood-cerebrospinal fluid barrier: relevance to neural disorders. Fluids Barriers CNS 2011; 8:13. [PMID: 21352605 PMCID: PMC3058069 DOI: 10.1186/2045-8118-8-13] [Citation(s) in RCA: 63] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2010] [Accepted: 02/28/2011] [Indexed: 12/24/2022] Open
Abstract
Guanidino compounds (GCs), such as creatine, phosphocreatine, guanidinoacetic acid, creatinine, methylguanidine, guanidinosuccinic acid, γ-guanidinobutyric acid, β-guanidinopropionic acid, guanidinoethane sulfonic acid and α-guanidinoglutaric acid, are present in the mammalian brain. Although creatine and phosphocreatine play important roles in energy homeostasis in the brain, accumulation of GCs may induce epileptic discharges and convulsions. This review focuses on how physiologically important and/or neurotoxic GCs are distributed in the brain under physiological and pathological conditions. Transporters for GCs at the blood-brain barrier (BBB) and the blood-cerebrospinal fluid (CSF) barrier (BCSFB) have emerged as substantial contributors to GCs distribution in the brain. Creatine transporter (CRT/solute carrier (SLC) 6A8) expressed at the BBB regulates creatine concentration in the brain, and represents a major pathway for supply of creatine from the circulating blood to the brain. CRT may be a key factor facilitating blood-to-brain guanidinoacetate transport in patients deficient in S-adenosylmethionine:guanidinoacetate N-methyltransferase, the creatine biosynthetic enzyme, resulting in cerebral accumulation of guanidinoacetate. CRT, taurine transporter (TauT/SLC6A6) and organic cation transporter (OCT3/SLC22A3) expressed at the BCSFB are involved in guanidinoacetic acid or creatinine efflux transport from CSF. Interestingly, BBB efflux transport of GCs, including guanidinoacetate and creatinine, is negligible, though the BBB has a variety of efflux transport systems for synthetic precursors of GCs, such as amino acids and neurotransmitters. Instead, the BCSFB functions as a major cerebral clearance system for GCs. In conclusion, transport of GCs at the BBB and BCSFB appears to be the key determinant of the cerebral levels of GCs, and changes in the transport characteristics may cause the abnormal distribution of GCs in the brain seen in patients with certain neurological disorders.
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Affiliation(s)
- Masanori Tachikawa
- Department of Pharmaceutics, Graduate School of Medicine and Pharmaceutical Sciences, University of Toyama, Toyama, Japan.
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19
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Li Z, Zharikova A, Vaughan CH, Bastian J, Zandy S, Esperon L, Axman E, Rowland NE, Peris J. Intermittent high-dose ethanol exposures increase motivation for operant ethanol self-administration: possible neurochemical mechanism. Brain Res 2009; 1310:142-53. [PMID: 19944084 DOI: 10.1016/j.brainres.2009.11.029] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2009] [Revised: 11/07/2009] [Accepted: 11/11/2009] [Indexed: 11/24/2022]
Abstract
We investigated the neurochemical mechanism of how high-dose ethanol exposure may increase motivation for ethanol consumption. First, we developed an animal model of increased motivation for ethanol using a progressive ratio (PR) schedule. Sprague-Dawley rats were trained to administer 10% ethanol-containing gelatin or plain gelatin (on alternate weeks) in daily 30-min sessions under different fixed ratio (FR) and PR schedules. During FR schedules, rats self-administered about 1 g/kg ethanol, which was decreased to 0.4+/-0.03 g/kg under PR10. Rats then received four pairs of either 3 g/kg ethanol or saline injections during the weeks when the reinforcer was plain gelatin. During subsequent ethanol gel sessions, breakpoints and ethanol consumption rose 40% in the high-dose ethanol group by the fourth set of injections with no change in plain gel responding. Alterations in amino acids in the ventral striatum (VS) during PR10 responding for 10% ethanol gelatin and plain gelatin were measured using microdialysis sampling coupled with capillary electrophoresis and laser-induced fluorescence detection. There was greater release of taurine, glycine and glutamate in the NAC of the high-dose ethanol rats during 10% ethanol-containing gelatin responding, compared to the control rats or during plain gel responding. An increase in the release of glycine in this same brain region has recently been shown to be involved with anticipation of a reward. Thus, it appears that intermittent high-dose ethanol exposure not only increases motivation for ethanol responding but may also change neurotransmitter release that mediates anticipation of reinforcement, which may play a key role in the development of alcoholism.
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Affiliation(s)
- Zhimin Li
- Department of Pharmacodynamics, Box 100487, University of Florida, Gainesville, FL 32610, USA
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20
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Tachikawa M, Kasai Y, Yokoyama R, Fujinawa J, Ganapathy V, Terasaki T, Hosoya KI. The blood-brain barrier transport and cerebral distribution of guanidinoacetate in rats: involvement of creatine and taurine transporters. J Neurochem 2009; 111:499-509. [DOI: 10.1111/j.1471-4159.2009.06332.x] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
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Begriche K, Massart J, Fromenty B. Effects of β-aminoisobutyric acid on leptin production and lipid homeostasis: mechanisms and possible relevance for the prevention of obesity. Fundam Clin Pharmacol 2009; 24:269-82. [DOI: 10.1111/j.1472-8206.2009.00765.x] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
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22
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Flora SJS. Structural, chemical and biological aspects of antioxidants for strategies against metal and metalloid exposure. OXIDATIVE MEDICINE AND CELLULAR LONGEVITY 2009; 2:191-206. [PMID: 20716905 PMCID: PMC2763257 DOI: 10.4161/oxim.2.4.9112] [Citation(s) in RCA: 293] [Impact Index Per Article: 19.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/23/2009] [Revised: 05/28/2009] [Accepted: 05/28/2009] [Indexed: 02/08/2023]
Abstract
Oxidative stress contributes to the pathophysiology of exposure to heavy metals/metalloid. Beneficial renal effects of some medications, such as chelation therapy depend at least partially on the ability to alleviate oxidative stress. The administration of various natural or synthetic antioxidants has been shown to be of benefit in the prevention and attenuation of metal induced biochemical alterations. These include vitamins, N-acetylcysteine, alpha-lipoic acid, melatonin, dietary flavonoids and many others. Human studies are limited in this regard. Under certain conditions, surprisingly, the antioxidant supplements may exhibit pro-oxidant properties and even worsen metal induced toxic damage. To date, the evidence is insufficient to recommend antioxidant supplements in subject with exposure to metals. Prospective, controlled clinical trials on safety and effectiveness of different therapeutic antioxidant strategies either individually or in combination with chelating agent are indispensable. The present review focuses on structural, chemical and biological aspects of antioxidants particularly related to their chelating properties.
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Affiliation(s)
- Swaran J S Flora
- Department of Pharmacology and Toxicology, Defence Research and Development Establishment, Gwalior, India.
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23
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Navneet AK, Appukuttan TA, Pandey M, Mohanakumar KP. Taurine fails to protect against 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine-induced striatal dopamine depletion in mice. Amino Acids 2007; 35:457-61. [PMID: 17701098 DOI: 10.1007/s00726-007-0571-7] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2007] [Accepted: 06/12/2007] [Indexed: 11/25/2022]
Abstract
Taurine, a known antioxidant and neuroprotector has been investigated for its free radical scavenging action in vitro in isolated mitochondria, and tested whether it protects against 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-induced dopaminergic neurodegeneration in mice. Taurine (0.1-10 mM) did not affect 1-methyl-4-phenyl pyridinium-induced hydroxyl radical production in isolated mitochondria. Systemic administration of taurine (250 mg/kg, i.p.) caused a small, but significant loss of dopamine levels in the striatum of mice. Taurine failed to reverse MPTP-induced striatal dopamine depletion, but caused significant increase in dopamine turnover in these animals. In the light of the present study it may be suggested that consumption of taurine may neither help in scavenging of neurotoxic hydroxyl radicals in the brain mitochondria, nor would it help in blocking the process of neurodegeneration.
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Affiliation(s)
- A K Navneet
- Laboratory of Clinical and Experimental Neuroscience, Division of Cell Biology and Physiology, Indian Institute of Chemical Biology, Jadavpur, Kolkata, India
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Xu H, Wang W, Tang ZQ, Xu TL, Chen L. Taurine acts as a glycine receptor agonist in slices of rat inferior colliculus. Hear Res 2006; 220:95-105. [PMID: 16949227 DOI: 10.1016/j.heares.2006.07.005] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/06/2006] [Revised: 07/13/2006] [Accepted: 07/17/2006] [Indexed: 11/18/2022]
Abstract
Taurine is an important endogenous amino acid for neural development and for many physiological functions, but little is known about its functional role in the central auditory system. We investigated in young rats (P10-P14) the effects of taurine on the neuronal responses and synaptic transmissions in the central nucleus of the inferior colliculus (ICC) with a brain slice preparation and with whole-cell patch-clamp recordings. Perfusion of taurine at 1mM reliably evoked a current across the membrane and decreased the input resistance in neurons of the ICC. Taurine also depressed the spontaneous and current-evoked firing of ICC neurons. All these effects were reversible after washout and could be blocked by 3 microM strychnine, an antagonist of glycine receptors, but not by 10 microM bicuculline, an antagonist of GABA(A) receptors. When the inhibitory receptors were not pharmacologically blocked, taurine reversibly reduced the postsynaptic currents/potentials evoked by electrically stimulating the commissure of the inferior colliculus or the ipsilateral lateral lemniscus. The results demonstrate that taurine reduces the neuronal excitability and depresses the synaptic transmission in the ICC by activating glycine-gated chloride channels. Our findings suggest that taurine acts as a ligand of glycine receptors in the ICC and can be involved in the information processing of the central auditory system similarly like the neurotransmitter glycine.
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Affiliation(s)
- Han Xu
- Auditory Research Laboratory, School of Life Sciences, University of Science and Technology of China, Hefei 230027, China
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Chepkova AN, Sergeeva OA, Haas HL. Mechanisms of long-lasting enhancement of corticostriatal neurotransmission by taurine. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2006; 583:401-10. [PMID: 17153626 DOI: 10.1007/978-0-387-33504-9_45] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
The long-lasting enhancement of corticostriatal neurotransmission by taurine, LLE-TAU represents a complex phenomenon requiring concurrent activation of glycine, DA and Ach receptors as well as taurine uptake. The data on the mechanisms of corticostriatal LLE-TAU can be integrated in the following scheme. Taurine interaction with glycine and GABAA receptors causes depolarization of striatal medium spiny cells (Chepkova et al., 2002) which is enhanced by taurine electrogenic uptake by TauT (Sarkar et al., 2003). This depolarization leads to Ca2+ entry via low voltage gated Ca2+ channels. Muscarinic M1 receptors are expressed in medium spiny neurons (Yan et al., 2001) and regulate their excitability mostly via phospholipase C (PLC)/PKC cascade (Lin et al., 2004). Concurrent activation of M1 and PLC-coupled D1 receptors (O'Sullivan et al., 2004) can amplify Ca2+ signal via IP3- stimulated Ca2+ release from intracellular stores and stimulate PKC.
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Affiliation(s)
- Aisa N Chepkova
- Institute of Neurophysiology, Heinrich Heine University, Düsseldorf, D-40001, Germany (POB 101007).
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