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Liu D, Wang J, Tian E, Chen J, Kong W, Lu Y, Zhang S. mGluR1/IP3/ERK signaling pathway regulates vestibular compensation in ON UBCs of the cerebellar flocculus. CNS Neurosci Ther 2024; 30:e14419. [PMID: 37622292 PMCID: PMC10848063 DOI: 10.1111/cns.14419] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2023] [Revised: 07/16/2023] [Accepted: 08/09/2023] [Indexed: 08/26/2023] Open
Abstract
AIMS To investigate the role of mGluR1α in cerebellar unipolar brush cells (UBC) in mediating vestibular compensation (VC), using mGluR1α agonist and antagonist to modulate ON UBC neurons, and explore the mGluR1/IP3/extracellular signal-regulated kinase (ERK) signaling pathway. METHODS First, AAV virus that knockdown ON UBC (mGluR1α) were injected into cerebellar UBC by stereotactic, and verified by immunofluorescence and western blot. The effect on VC was evaluated after unilateral labyrinthectomy (UL). Second, saline, (RS)-3,5-dihydroxyphenylglycine (DHPG), and LY367385 were injected into tubes implanted in rats at different time points after UL separately. The effect on ON UBC neuron activity was evaluated by immunofluorescence. Then, Phosphoinositide (PI) and p-ERK1/2 levels of mGluR1α were analyzed by ELISA after UL. The protein levels of p-ERK and total ERK were verified by western blot. In addition, the effect of mGluR1α activation or inhibition on VC-related behavior was observed. RESULTS mGluR1α knockdown induced VC phenotypes. DHPG increased ON UBC activity, while LY367385 reduced ON UBC activity. DHPG group showed an increase in PI and p-ERK1/2 levels, while LY367385 group showed a decrease in PI and p-ERK1/2 levels in cerebellar UBC of rats. The western blot results of p-ERK and total ERK confirm and support the observations. DHPG alleviated VC-related behavior phenotypes, while LY367385 exacerbated vestibular decompensation-like behavior induced by UL. CONCLUSION mGluR1α activity in cerebellar ON UBC is crucial for mediating VC through the mGluR1/IP3/ERK signaling pathway, which affects ON UBC neuron activity and contributes to the pathogenesis of VC.
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Affiliation(s)
- Dan Liu
- Department of Otorhinolaryngology, Union Hospital, Tongji Medical CollegeHuazhong University of Science and TechnologyWuhanChina
- Institute of Otorhinolaryngology, Union Hospital, Tongji Medical CollegeHuazhong University of Science and TechnologyWuhanChina
| | - Jun Wang
- Department of Otorhinolaryngology, Union Hospital, Tongji Medical CollegeHuazhong University of Science and TechnologyWuhanChina
- Institute of Otorhinolaryngology, Union Hospital, Tongji Medical CollegeHuazhong University of Science and TechnologyWuhanChina
| | - E. Tian
- Department of Otorhinolaryngology, Union Hospital, Tongji Medical CollegeHuazhong University of Science and TechnologyWuhanChina
- Institute of Otorhinolaryngology, Union Hospital, Tongji Medical CollegeHuazhong University of Science and TechnologyWuhanChina
| | - Jingyu Chen
- Department of Otorhinolaryngology, Union Hospital, Tongji Medical CollegeHuazhong University of Science and TechnologyWuhanChina
- Institute of Otorhinolaryngology, Union Hospital, Tongji Medical CollegeHuazhong University of Science and TechnologyWuhanChina
| | - Weijia Kong
- Department of Otorhinolaryngology, Union Hospital, Tongji Medical CollegeHuazhong University of Science and TechnologyWuhanChina
- Institute of Otorhinolaryngology, Union Hospital, Tongji Medical CollegeHuazhong University of Science and TechnologyWuhanChina
| | - Yisheng Lu
- Department of Physiology, School of Basic MedicineHuazhong University of Science and TechnologyWuhanChina
- Institute of Brain Research, Collaborative Innovation Center for Brain ScienceHuazhong University of Science and TechnologyWuhanChina
| | - Sulin Zhang
- Department of Otorhinolaryngology, Union Hospital, Tongji Medical CollegeHuazhong University of Science and TechnologyWuhanChina
- Institute of Otorhinolaryngology, Union Hospital, Tongji Medical CollegeHuazhong University of Science and TechnologyWuhanChina
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Tian P, Zhang W, Li KY, Li HW, Ma K, Han DE. [Effect of Rehmanniae Radix on depression-like behavior and hippocampal monoamine neurotransmitters of chronic unpredictable mild stress model rats]. Zhongguo Zhong Yao Za Zhi 2022; 47:4691-4697. [PMID: 36164876 DOI: 10.19540/j.cnki.cjcmm.20220421.401] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
To investigate the effect of Rehmanniae Radix on depression-like behavior and monoamine neurotransmitters of chronic unpredictable mild stress(CUMS) model rats. CUMS combined with isolated feeding was used to induce the depression model of rats. The depression-like behavior of rats was evaluated by sucrose preference test, open field test, and forced swim test. Hematoxylin-Eosin(HE) staining was used to investigate the pathological changes of neurons in the CA1 and CA3 area of hippocampus. Ultra performance liquid chromatography-tandem mass spectrometry(UPLC-MS) was used to detect the contents of 5-hydroxytryptamine(5-HT), 5-hydroxyindoleacetic acid(5-HIAA), dopamine(DA), 3,4-dihydroxyphenylacetic acid(DOPAC), homovanillic acid(HVA), norepinephrine(NE), and 3-methoxy-4-hydroxyphenyl glycol(MHPG) in rats. Western blot was used to detect the protein expressions of tryptophan hydroxylase 2(TPH2), serotonin transporter(SERT), and monoamine oxidase A(MAO-A) in the hippocampus of rats. Compared with the normal group, depressive-like behavior of rats was obvious in the model group. The arrangements of neurons in the CA1 and CA3 area of hippocampus were loose and disorderly. The levels of 5-HT, 5-HIAA, and 5-HT/5-HIAA in the hippocampal area were decreased(P<0.01). The protein expression of TPH2 was decreased(P<0.01), but those of SERT and MAO-A were increased(P<0.01). In the Rehmanniae Radix groups with 1.8 g·kg~(-1) and 7.2 g·kg~(-1), the depression-like behavior of CUMS rats and pathological changes of neurons in CA1, CA3 area of hippocampus were improved. The protein expression of TPH2(P<0.05, P<0.01) was increased, and those of SERT and MAO-A were down-regulated(P<0.05, P<0.01). The levels of 5-HT, 5-HIAA, and 5-HT/5-HIAA in hippocampus were increased(P<0.05, P<0.01). The changes in DA, DOPAC, HVA, DA/(DOPAC +HVA), NE, DHPG, and NE/DHPG were not statistically significant. The results suggested that Rehmanniae Radix improved depression-like behavior of CUMS rats, and the mechanism might be related to the regulation of synthesis, transportation, and metabolism of 5-HT neurotransmitter in the hippocampus.
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Affiliation(s)
- Ping Tian
- Henan Academy of Chinese Medicine Zhengzhou 450004, China
| | - Wei Zhang
- Henan Academy of Chinese Medicine Zhengzhou 450004, China
| | - Kai-Yan Li
- Henan Academy of Chinese Medicine Zhengzhou 450004, China
| | - Hong-Wei Li
- School of Pharmacy, Henan University of Chinese Medicine Zhengzhou 450046, China
| | - Kai Ma
- Henan Academy of Chinese Medicine Zhengzhou 450004, China
| | - De-En Han
- School of Pharmacy, Henan University of Chinese Medicine Zhengzhou 450046, China
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Lautz JD, Tsegay KB, Zhu Z, Gniffke EP, Welsh JP, Smith SEP. Synaptic protein interaction networks encode experience by assuming stimulus-specific and brain-region-specific states. Cell Rep 2021; 37:110076. [PMID: 34852231 PMCID: PMC8722361 DOI: 10.1016/j.celrep.2021.110076] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2021] [Revised: 10/01/2021] [Accepted: 11/09/2021] [Indexed: 11/02/2022] Open
Abstract
A core network of widely expressed proteins within the glutamatergic post-synapse mediates activity-dependent synaptic plasticity throughout the brain, but the specific proteomic composition of synapses differs between brain regions. Here, we address the question, how does proteomic composition affect activity-dependent protein-protein interaction networks (PINs) downstream of synaptic activity? Using quantitative multiplex co-immunoprecipitation, we compare the PIN response of in vivo or ex vivo neurons derived from different brain regions to activation by different agonists or different forms of eyeblink conditioning. We report that PINs discriminate between incoming stimuli using differential kinetics of overlapping and non-overlapping PIN parameters. Further, these "molecular logic rules" differ by brain region. We conclude that although the PIN of the glutamatergic post-synapse is expressed widely throughout the brain, its activity-dependent dynamics show remarkable stimulus-specific and brain-region-specific diversity. This diversity may help explain the challenges in developing molecule-specific drug therapies for neurological disorders.
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Affiliation(s)
- Jonathan D Lautz
- Center for Integrative Brain Research, Seattle Children's Research Institute, Seattle, WA, USA
| | - Kaleb B Tsegay
- Center for Integrative Brain Research, Seattle Children's Research Institute, Seattle, WA, USA
| | - Zhiyi Zhu
- Center for Integrative Brain Research, Seattle Children's Research Institute, Seattle, WA, USA
| | - Edward P Gniffke
- Center for Integrative Brain Research, Seattle Children's Research Institute, Seattle, WA, USA
| | - John P Welsh
- Center for Integrative Brain Research, Seattle Children's Research Institute, Seattle, WA, USA; Department of Pediatrics, University of Washington, Seattle, WA, USA
| | - Stephen E P Smith
- Center for Integrative Brain Research, Seattle Children's Research Institute, Seattle, WA, USA; Department of Pediatrics, University of Washington, Seattle, WA, USA; Graduate Program in Neuroscience, University of Washington, Seattle, WA, USA.
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Durakoglugil MS, Wasser CR, Wong CH, Pohlkamp T, Xian X, Lane-Donovan C, Fritschle K, Naestle L, Herz J. Reelin Regulates Neuronal Excitability through Striatal-Enriched Protein Tyrosine Phosphatase (STEP 61) and Calcium Permeable AMPARs in an NMDAR-Dependent Manner. J Neurosci 2021; 41:7340-7349. [PMID: 34290083 PMCID: PMC8412985 DOI: 10.1523/jneurosci.0388-21.2021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2021] [Revised: 06/13/2021] [Accepted: 07/08/2021] [Indexed: 11/21/2022] Open
Abstract
Alzheimer's disease (AD) is a progressive neurodegenerative disease marked by the accumulation of amyloid-β (Aβ) plaques and neurofibrillary tangles. Aβ oligomers cause synaptic dysfunction early in AD by enhancing long-term depression (LTD; a paradigm for forgetfulness) via metabotropic glutamate receptor (mGluR)-dependent regulation of striatal-enriched tyrosine phosphatase (STEP61). Reelin is a neuromodulator that signals through ApoE (apolipoprotein E) receptors to protect the synapse against Aβ toxicity (Durakoglugil et al., 2009) Reelin signaling is impaired by ApoE4, the most important genetic risk factor for AD, and Aβ-oligomers activate metabotropic glutamate receptors (Renner et al., 2010). We therefore asked whether Reelin might also affect mGluR-LTD. To this end, we induced chemical mGluR-LTD using DHPG (Dihydroxyphenylglycine), a selective mGluR5 agonist. We found that exogenous Reelin reduces the DHPG-induced increase in STEP61, prevents the dephosphorylation of GluA2, and concomitantly blocks mGluR-mediated LTD. By contrast, Reelin deficiency increased expression of Ca2+-permeable GluA2-lacking AMPA receptors along with higher STEP61 levels, resulting in occlusion of DHPG-induced LTD in hippocampal CA1 neurons. We propose a model in which Reelin modulates local protein synthesis as well as AMPA receptor subunit composition through modulation of mGluR-mediated signaling with implications for memory consolidation or neurodegeneration.SIGNIFICANCE STATEMENT Reelin is an important neuromodulator, which in the adult brain controls synaptic plasticity and protects against neurodegeneration. Amyloid-β has been shown to use mGluRs to induce synaptic depression through endocytosis of NMDA and AMPA receptors, a mechanism referred to as LTD, a paradigm of forgetfulness. Our results show that Reelin regulates the phosphatase STEP, which plays an important role in neurodegeneration, as well as the expression of calcium-permeable AMPA receptors, which play a role in memory formation. These data suggest that Reelin uses mGluR LTD pathways to regulate memory formation as well as neurodegeneration.
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Affiliation(s)
- Murat S Durakoglugil
- Department of Molecular Genetics
- Center for Translational Neurodegeneration Research
| | - Catherine R Wasser
- Department of Molecular Genetics
- Center for Translational Neurodegeneration Research
| | - Connie H Wong
- Department of Molecular Genetics
- Center for Translational Neurodegeneration Research
| | - Theresa Pohlkamp
- Department of Molecular Genetics
- Center for Translational Neurodegeneration Research
| | - Xunde Xian
- Institute of Cardiovascular Sciences and Key Laboratory of Molecular Cardiovascular Sciences, Ministry of Education, Peking University, Beijing 100871, China
| | - Courtney Lane-Donovan
- Weill Institute for Neurosciences, University of California San Francisco, San Francisco, California 94158
| | | | - Lea Naestle
- Ludwig-Maximilians University of Munich, 80539, Munich, Germany
| | - Joachim Herz
- Department of Molecular Genetics
- Center for Translational Neurodegeneration Research
- Departments of Neuroscience and
- Neurology and Neurotherapeutics, University of Texas Southwestern Medical Center, Dallas, Texas 75390
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van Gelder CAGH, Penning R, Veth TS, Catsburg LAE, Hoogenraad CC, MacGillavry HD, Altelaar M. Temporal Quantitative Proteomics of mGluR-induced Protein Translation and Phosphorylation in Neurons. Mol Cell Proteomics 2020; 19:1952-1968. [PMID: 32912969 PMCID: PMC7710149 DOI: 10.1074/mcp.ra120.002199] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2020] [Revised: 09/04/2020] [Indexed: 01/12/2023] Open
Abstract
At neuronal synapses, activation of group I metabotropic glutamate receptors (mGluR1/5) triggers a form of long-term depression (mGluR-LTD) that relies on new protein synthesis and the internalization of AMPA-type glutamate receptors. Dysregulation of these processes has been implicated in the development of mental disorders such as autism spectrum disorders and therefore merit a better understanding on a molecular level. Here, to study mGluR-induced signaling pathways, we integrated quantitative phosphoproteomics with the analyses of newly synthesized proteins via bio-orthogonal amino acids (azidohomoalanine) in a pulsed labeling strategy in cultured hippocampal neurons stimulated with DHPG, a specific agonist for group I mGluRs. We identified several kinases with important roles in DHPG-induced mGluR activation, which we confirmed using small molecule kinase inhibitors. Furthermore, changes in the AMPA receptor endocytosis pathway in both protein synthesis and protein phosphorylation were identified, whereby Intersectin-1 was validated as a novel player in this pathway. This study revealed several new insights into the molecular pathways downstream of group I mGluR activation in hippocampal neurons, and provides a rich resource for further analyses.
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Affiliation(s)
- Charlotte A G H van Gelder
- Biomolecular Mass Spectrometry and Proteomics, Bijvoet Center for Biomolecular Research, and Utrecht Institute for Pharmaceutical Sciences, Utrecht University, Utrecht, The Netherlands; Netherlands Proteomics Center, Utrecht, The Netherlands
| | - Renske Penning
- Biomolecular Mass Spectrometry and Proteomics, Bijvoet Center for Biomolecular Research, and Utrecht Institute for Pharmaceutical Sciences, Utrecht University, Utrecht, The Netherlands; Netherlands Proteomics Center, Utrecht, The Netherlands
| | - Tim S Veth
- Biomolecular Mass Spectrometry and Proteomics, Bijvoet Center for Biomolecular Research, and Utrecht Institute for Pharmaceutical Sciences, Utrecht University, Utrecht, The Netherlands; Netherlands Proteomics Center, Utrecht, The Netherlands
| | - Lisa A E Catsburg
- Cell Biology, Department of Biology, Faculty of Science, Utrecht University, Utrecht, The Netherlands
| | - Casper C Hoogenraad
- Cell Biology, Department of Biology, Faculty of Science, Utrecht University, Utrecht, The Netherlands
| | - Harold D MacGillavry
- Cell Biology, Department of Biology, Faculty of Science, Utrecht University, Utrecht, The Netherlands.
| | - Maarten Altelaar
- Biomolecular Mass Spectrometry and Proteomics, Bijvoet Center for Biomolecular Research, and Utrecht Institute for Pharmaceutical Sciences, Utrecht University, Utrecht, The Netherlands; Netherlands Proteomics Center, Utrecht, The Netherlands.
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Hien A, Molinaro G, Liu B, Huber KM, Richter JD. Ribosome profiling in mouse hippocampus: plasticity-induced regulation and bidirectional control by TSC2 and FMRP. Mol Autism 2020; 11:78. [PMID: 33054857 PMCID: PMC7556950 DOI: 10.1186/s13229-020-00384-9] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2020] [Accepted: 09/23/2020] [Indexed: 01/09/2023] Open
Abstract
BACKGROUND Mutations in TSC2 are the most common cause of tuberous sclerosis (TSC), a disorder with a high incidence of autism and intellectual disability. TSC2 regulates mRNA translation required for group 1 metabotropic glutamate receptor-dependent synaptic long-term depression (mGluR-LTD) and behavior, but the identity of mRNAs responsive to mGluR-LTD signaling is largely unknown. METHODS We utilized Tsc2+/- mice as a mouse model of TSC and prepared hippocampal slices from these animals. We induced mGluR-LTD synaptic plasticity in slices and processed the samples for RNA-seq and ribosome profiling to identify differentially expressed genes in Tsc2+/- and following mGluR-LTD synaptic plasticity. RESULTS Ribosome profiling reveals that in Tsc2+/- mouse hippocampal slices, the expression of several mRNAs was dysregulated: terminal oligopyrimidine (TOP)-containing mRNAs decreased, while FMRP-binding targets increased. Remarkably, we observed the opposite changes of FMRP binding targets in Fmr1-/y hippocampi. In wild-type hippocampus, induction of mGluR-LTD caused rapid changes in the steady-state levels of hundreds of mRNAs, many of which are FMRP targets. Moreover, mGluR-LTD failed to promote phosphorylation of eukaryotic elongation factor 2 (eEF2) in TSC mice, and chemically mimicking phospho-eEF2 with low cycloheximide enhances mGluR-LTD in TSC mice. CONCLUSION These results suggest a molecular basis for bidirectional regulation of synaptic plasticity and behavior by TSC2 and FMRP. Our study also suggests that altered mGluR-regulated translation elongation contributes to impaired synaptic plasticity in Tsc2+/- mice.
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Affiliation(s)
- Annie Hien
- Program in Molecular Medicine, University of Massachusetts Medical School, Worcester, MA, 01605, USA
- Medical Scientist Training Program, University of Massachusetts Medical School, Worcester, MA, 01655, USA
| | - Gemma Molinaro
- Department of Neuroscience, University of Texas Southwestern Medical Center, Dallas, TX, 75390, USA
| | - Botao Liu
- Program in Molecular Medicine, University of Massachusetts Medical School, Worcester, MA, 01605, USA
| | - Kimberly M Huber
- Department of Neuroscience, University of Texas Southwestern Medical Center, Dallas, TX, 75390, USA.
| | - Joel D Richter
- Program in Molecular Medicine, University of Massachusetts Medical School, Worcester, MA, 01605, USA.
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Kepura F, Braun E, Dietrich A, Plant TD. TRPC1 Regulates the Activity of a Voltage-Dependent Nonselective Cation Current in Hippocampal CA1 Neurons. Cells 2020; 9:cells9020459. [PMID: 32085504 PMCID: PMC7072794 DOI: 10.3390/cells9020459] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2019] [Revised: 02/12/2020] [Accepted: 02/14/2020] [Indexed: 12/26/2022] Open
Abstract
The cation channel subunit TRPC1 is strongly expressed in central neurons including neurons in the CA1 region of the hippocampus where it forms complexes with TRPC4 and TRPC5. To investigate the functional role of TRPC1 in these neurons and in channel function, we compared current responses to group I metabotropic glutamate receptor (mGluR I) activation and looked for major differences in dendritic morphology in neurons from TRPC1+/+ and TRPC1-/- mice. mGluR I stimulation resulted in the activation of a voltage-dependent nonselective cation current in both genotypes. Deletion of TRPC1 resulted in a modification of the shape of the current-voltage relationship, leading to an inward current increase. In current clamp recordings, the percentage of neurons that responded to depolarization in the presence of an mGluR I agonist with a plateau potential was increased in TRPC1-/- mice. There was also a small increase in the minor population of CA1 neurons that have more than one apical dendrite in TRPC1-/- mice. We conclude that TRPC1 has an inhibitory effect on receptor-operated nonselective cation channels in hippocampal CA1 neurons probably as a result of heterotetramer formation with other TRPC isoforms, and that TRPC1 deletion has only minor effects on dendritic morphology.
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Affiliation(s)
- Frauke Kepura
- Pharmakologisches Institut, BPC-Marburg, Fachbereich Medizin, Philipps-Universität Marburg, Karl-von-Frisch-Straße 2, 35043 Marburg, Germany; (F.K.); (E.B.); (A.D.)
| | - Eva Braun
- Pharmakologisches Institut, BPC-Marburg, Fachbereich Medizin, Philipps-Universität Marburg, Karl-von-Frisch-Straße 2, 35043 Marburg, Germany; (F.K.); (E.B.); (A.D.)
| | - Alexander Dietrich
- Pharmakologisches Institut, BPC-Marburg, Fachbereich Medizin, Philipps-Universität Marburg, Karl-von-Frisch-Straße 2, 35043 Marburg, Germany; (F.K.); (E.B.); (A.D.)
- Walther-Straub-Institut für Pharmakologie und Toxikologie, Ludwig-Maximilians-Universität München, 80336 München, Germany
| | - Tim D. Plant
- Pharmakologisches Institut, BPC-Marburg, Fachbereich Medizin, Philipps-Universität Marburg, Karl-von-Frisch-Straße 2, 35043 Marburg, Germany; (F.K.); (E.B.); (A.D.)
- Center for Mind, Brain and Behavior, Philipps-Universität Marburg, 35032 Marburg, Germany
- Correspondence: ; Tel.: +49-6421-28-65038
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Singh R, Saxena A, Giri L. Single Neuron Imaging Reveals Metabotropic Glutamate Receptor-Mediated Bursting and Delay in Calcium Oscillation in Hippocampal Neurons. Annu Int Conf IEEE Eng Med Biol Soc 2020; 2019:5146-5149. [PMID: 31947017 DOI: 10.1109/embc.2019.8856638] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Measurement of cytosolic calcium activity in single neuron and quantification of response to drug treatment over a longer period remain challenging. Especially, analysis of amplitude, frequency, and delay in calcium response in G-protein coupled receptors (GPCR) targeting drug-treated neurons is complicated due to inherent heterogeneity. To address this, we have utilized k- means clustering to identify various sub-populations. Here we focus on measuring drug dose response in the single neuron by means of high-resolution confocal imaging. Metabotropic glutamate receptor was activated using 3,5-dihydroxyphenylglycine (DHPG). The result reveals an unusual delay in calcium response for higher dose particularly in responding neurons. The proposed methodology can be used for selection of drug dose and optimization of the time window for neurodegenerative diseases.
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Kalampaliki AD, Giannouli V, Skaltsounis AL, Kostakis IK. A Three-Step, Gram-Scale Synthesis of Hydroxytyrosol, Hydroxytyrosol Acetate, and 3,4-Dihydroxyphenylglycol. Molecules 2019; 24:E3239. [PMID: 31492013 PMCID: PMC6767028 DOI: 10.3390/molecules24183239] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2019] [Revised: 09/01/2019] [Accepted: 09/03/2019] [Indexed: 12/11/2022] Open
Abstract
Hydroxytyrosol and two other polyphenols of olive tree, hydroxytyrosol acetate and 3,4-dihydroxyphenylglycol, are known for a wide range of beneficial activities in human health and prevention from diseases. The inability to isolate high, pure amounts of these natural compounds and the difficult and laborious procedures for the synthesis of them led us to describe herein an efficient, easy, cheap, and scaling up synthetic procedure, from catechol, via microwave irradiation.
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Affiliation(s)
- Amalia D Kalampaliki
- Division of Pharmaceutical Chemistry, Department of Pharmacy, National and Kapodistrian University of Athens, Panepistimiopolis-Zografou, 15771 Athens, Greece.
| | - Vassiliki Giannouli
- Division of Pharmaceutical Chemistry, Department of Pharmacy, National and Kapodistrian University of Athens, Panepistimiopolis-Zografou, 15771 Athens, Greece.
| | - Alexios-Leandros Skaltsounis
- Division of Pharmacognosy & Natural Product Chemistry, Department of Pharmacy, National and Kapodistrian University of Athens, Panepistimiopolis-Zografou, 15771 Athens, Greece.
| | - Ioannis K Kostakis
- Division of Pharmaceutical Chemistry, Department of Pharmacy, National and Kapodistrian University of Athens, Panepistimiopolis-Zografou, 15771 Athens, Greece.
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Galván I, Solano F, Zougagh M, de Andrés F, Murtada K, Ríos Á, de la Peña E, Carranza J. Unprecedented high catecholamine production causing hair pigmentation after urinary excretion in red deer. Cell Mol Life Sci 2019; 76:397-404. [PMID: 30413834 PMCID: PMC11105493 DOI: 10.1007/s00018-018-2962-1] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2018] [Revised: 10/29/2018] [Accepted: 10/31/2018] [Indexed: 10/27/2022]
Abstract
Hormones have not been found in concentrations of orders of magnitude higher than nanograms per milliliter. Here, we report urine concentrations of a catecholamine (norepinephrine) ranging from 0.05 to 0.5 g/l, and concentrations of its metabolite DL-3,4-dihydroxyphenyl glycol (DOPEG) ranging from 1.0 to 44.5 g/l, in wild male red deer Cervus elaphus hispanicus after LC-MS analyses. The dark ventral patch of male red deer, a recently described sexually selected signal, contains high amounts of DOPEG (0.9-266.9 mg/l) stuck in the hairs, while DOPEG is not present in non-darkened hair. The formation of this dark patch is explained by the chemical structure of DOPEG, which is a catecholamine-derived o-diphenol susceptible to be oxidized by air and form allomelanins, nitrogen-free pigments similar to cutaneous melanins; by its high concentration in urine; and by the urine spraying behavior of red deer by which urine is spread through the ventral body area. Accordingly, the size of the dark ventral patch was positively correlated with the concentration of DOPEG in urine, which was in turn correlated with DOPEG absorbed in ventral hair. These findings represent catecholamine concentrations about one million higher than those previously reported for any hormone in an organism. This may have favored the evolution of the dark ventral patch of red deer by transferring information on the fighting capacity to rivals and mates. Physiological limits for hormone production in animals are thus considerably higher than previously thought. These results also unveil a novel mechanism of pigmentation based on the self-application of urine over the fur.
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Affiliation(s)
- Ismael Galván
- Department of Evolutionary Ecology, Doñana Biological Station, Consejo Superior de Investigaciones Científicas (CSIC), C/ Américo Vespucio 26, 41092, Seville, Spain.
| | - Francisco Solano
- Department of Biochemistry and Molecular Biology B and Immunology, Faculty of Medicine, University of Murcia, Campus de Espinardo, 30100, Murcia, Spain
| | - Mohammed Zougagh
- Regional Institute for Applied Scientific Research (IRICA), University of Castilla-La Mancha, Ciudad Real, Spain
- Department of Analytical Chemistry and Food Technology, Faculty of Pharmacy, University of Castilla-La Mancha, Albacete, Spain
| | - Fernando de Andrés
- Regional Institute for Applied Scientific Research (IRICA), University of Castilla-La Mancha, Ciudad Real, Spain
- Department of Analytical Chemistry and Food Technology, Faculty of Pharmacy, University of Castilla-La Mancha, Albacete, Spain
| | - Khaled Murtada
- Regional Institute for Applied Scientific Research (IRICA), University of Castilla-La Mancha, Ciudad Real, Spain
- Department of Analytical Chemistry and Food Technology, Faculty of Chemical Science and Technology, University of Castilla-La Mancha, Ciudad Real, Spain
| | - Ángel Ríos
- Regional Institute for Applied Scientific Research (IRICA), University of Castilla-La Mancha, Ciudad Real, Spain
- Department of Analytical Chemistry and Food Technology, Faculty of Chemical Science and Technology, University of Castilla-La Mancha, Ciudad Real, Spain
| | - Eva de la Peña
- Ungulate Research Unit, Cátedra de Recursos Cinegéticos y Piscícolas (CRCP), University of Cordoba, Campus de Rabanales, 14071, Córdoba, Spain
| | - Juan Carranza
- Ungulate Research Unit, Cátedra de Recursos Cinegéticos y Piscícolas (CRCP), University of Cordoba, Campus de Rabanales, 14071, Córdoba, Spain
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11
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Sanderson TM, Bradley CA, Georgiou J, Hong YH, Ng AN, Lee Y, Kim HD, Kim D, Amici M, Son GH, Zhuo M, Kim K, Kaang BK, Kim SJ, Collingridge GL. The Probability of Neurotransmitter Release Governs AMPA Receptor Trafficking via Activity-Dependent Regulation of mGluR1 Surface Expression. Cell Rep 2018; 25:3631-3646.e3. [PMID: 30590038 PMCID: PMC6315206 DOI: 10.1016/j.celrep.2018.12.010] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2018] [Revised: 09/28/2018] [Accepted: 12/03/2018] [Indexed: 12/14/2022] Open
Abstract
A major mechanism contributing to synaptic plasticity involves alterations in the number of AMPA receptors (AMPARs) expressed at synapses. Hippocampal CA1 synapses, where this process has been most extensively studied, are highly heterogeneous with respect to their probability of neurotransmitter release, P(r). It is unknown whether there is any relationship between the extent of plasticity-related AMPAR trafficking and the initial P(r) of a synapse. To address this question, we induced metabotropic glutamate receptor (mGluR) dependent long-term depression (mGluR-LTD) and assessed AMPAR trafficking and P(r) at individual synapses, using SEP-GluA2 and FM4-64, respectively. We found that either pharmacological or synaptic activation of mGluR1 reduced synaptic SEP-GluA2 in a manner that depends upon P(r); this process involved an activity-dependent reduction in surface mGluR1 that selectively protects high-P(r) synapses from synaptic weakening. Consequently, the extent of postsynaptic plasticity can be pre-tuned by presynaptic activity.
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Affiliation(s)
- Thomas M Sanderson
- Department of Brain and Cognitive Sciences, College of Natural Sciences, Seoul National University, Seoul 151-746, Korea; Neuroscience Research Institute, Seoul National University College of Medicine, 28 Yeongeon-dong, Jongno-gu, Seoul 110-799, Korea; School of Physiology, Pharmacology & Neuroscience, University of Bristol, Dorothy Hodgkin Building, Whitson Street, Bristol BS1 3NY, UK; Lunenfeld-Tanenbaum Research Institute, Mount Sinai Hospital, Toronto, ON M5G 1X5, Canada
| | - Clarrisa A Bradley
- Department of Brain and Cognitive Sciences, College of Natural Sciences, Seoul National University, Seoul 151-746, Korea; Neuroscience & Mental Health Program, The Hospital for Sick Children, Toronto, ON, Canada
| | - John Georgiou
- Lunenfeld-Tanenbaum Research Institute, Mount Sinai Hospital, Toronto, ON M5G 1X5, Canada
| | - Yun Hwa Hong
- Neuroscience Research Institute, Seoul National University College of Medicine, 28 Yeongeon-dong, Jongno-gu, Seoul 110-799, Korea; Department of Physiology, Seoul National University College of Medicine, 28, Yeongeon-dong, Jongno-gu, Seoul 110-799, Korea
| | - Ai Na Ng
- School of Physiology, Pharmacology & Neuroscience, University of Bristol, Dorothy Hodgkin Building, Whitson Street, Bristol BS1 3NY, UK
| | - Yeseul Lee
- Department of Brain and Cognitive Sciences, College of Natural Sciences, Seoul National University, Seoul 151-746, Korea; School of Physiology, Pharmacology & Neuroscience, University of Bristol, Dorothy Hodgkin Building, Whitson Street, Bristol BS1 3NY, UK
| | - Hee-Dae Kim
- Department of Brain and Cognitive Sciences, DGIST, and Korea Brain Institute (KBRI), Daegu, 41068, Korea
| | - Doyeon Kim
- Department of Brain and Cognitive Sciences, DGIST, and Korea Brain Institute (KBRI), Daegu, 41068, Korea
| | - Mascia Amici
- School of Physiology, Pharmacology & Neuroscience, University of Bristol, Dorothy Hodgkin Building, Whitson Street, Bristol BS1 3NY, UK
| | - Gi Hoon Son
- Department of Biomedical Sciences, Korea University College of Medicine, Seoul 136-705, Seoul, Korea
| | - Min Zhuo
- Department of Brain and Cognitive Sciences, College of Natural Sciences, Seoul National University, Seoul 151-746, Korea; Department of Physiology, Faculty of Medicine, University of Toronto, Toronto, ON M5S 1A8, Canada; Department of Biological Sciences, College of Natural Sciences, Seoul National University, Building 504, Room 202, 599 Gwanangno, Gwanak-gu 151-747, Seoul, Korea; Center for Neuron and Disease, Frontier Institutes of Science and Technology, Xi'an Jiaotong University, Xi'an, 710049, China
| | - Kyungjin Kim
- Department of Brain and Cognitive Sciences, DGIST, and Korea Brain Institute (KBRI), Daegu, 41068, Korea
| | - Bong-Kiun Kaang
- Department of Brain and Cognitive Sciences, College of Natural Sciences, Seoul National University, Seoul 151-746, Korea; Department of Biological Sciences, College of Natural Sciences, Seoul National University, Building 504, Room 202, 599 Gwanangno, Gwanak-gu 151-747, Seoul, Korea; Center for Neuron and Disease, Frontier Institutes of Science and Technology, Xi'an Jiaotong University, Xi'an, 710049, China
| | - Sang Jeong Kim
- Department of Brain and Cognitive Sciences, College of Natural Sciences, Seoul National University, Seoul 151-746, Korea; Neuroscience Research Institute, Seoul National University College of Medicine, 28 Yeongeon-dong, Jongno-gu, Seoul 110-799, Korea; Department of Physiology, Seoul National University College of Medicine, 28, Yeongeon-dong, Jongno-gu, Seoul 110-799, Korea.
| | - Graham L Collingridge
- Department of Brain and Cognitive Sciences, College of Natural Sciences, Seoul National University, Seoul 151-746, Korea; School of Physiology, Pharmacology & Neuroscience, University of Bristol, Dorothy Hodgkin Building, Whitson Street, Bristol BS1 3NY, UK; Lunenfeld-Tanenbaum Research Institute, Mount Sinai Hospital, Toronto, ON M5G 1X5, Canada; Department of Physiology, Faculty of Medicine, University of Toronto, Toronto, ON M5S 1A8, Canada.
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12
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Bermúdez-Oria A, Rodríguez-Gutiérrez G, Rodríguez-Juan E, González-Benjumea A, Fernández-Bolaños J. Molecular interactions between 3,4-dihydroxyphenylglycol and pectin and antioxidant capacity of this complex in vitro. Carbohydr Polym 2018; 197:260-268. [PMID: 30007612 DOI: 10.1016/j.carbpol.2018.05.089] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2017] [Revised: 05/28/2018] [Accepted: 05/30/2018] [Indexed: 11/18/2022]
Abstract
This study explored the interaction of pectin with 3,4-dihydroxyphenylglycol (DHPG), a potent phenolic antioxidant naturally found in olive fruit, via encapsulation into pectinate beads. MALDI TOF-TOF analysis supported the formation of complexes between DHPG and pectin. A combination of covalent bonds (ester bonds) and non-covalent interactions, mostly hydrogen bonding, were suggested as the cause of DHPG-pectin complex formation. Free radical scavenging assays confirmed that DHPG maintained its antioxidant activity after complexation and after a digestion simulated in vitro with gastric and intestinal fluids. Therefore, DHPG-pectin beads could reach the large intestine and contribute to a healthy antioxidant environment.
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Affiliation(s)
- Alejandra Bermúdez-Oria
- Department of Food Phytochemistry, Instituto de la Grasa (Spanish National Research Council, CSIC), Ctra. de Utrera km. 1, Pablo de Olavide University Campus, Building 46, 41013 Seville, Spain
| | - Guillermo Rodríguez-Gutiérrez
- Department of Food Phytochemistry, Instituto de la Grasa (Spanish National Research Council, CSIC), Ctra. de Utrera km. 1, Pablo de Olavide University Campus, Building 46, 41013 Seville, Spain
| | - Elisa Rodríguez-Juan
- Department of Food Phytochemistry, Instituto de la Grasa (Spanish National Research Council, CSIC), Ctra. de Utrera km. 1, Pablo de Olavide University Campus, Building 46, 41013 Seville, Spain
| | - Alejandro González-Benjumea
- Department of Organic Chemistry, Faculty of Chemistry, University of Seville, Profesor García González 1, Seville 41012, Spain
| | - Juan Fernández-Bolaños
- Department of Food Phytochemistry, Instituto de la Grasa (Spanish National Research Council, CSIC), Ctra. de Utrera km. 1, Pablo de Olavide University Campus, Building 46, 41013 Seville, Spain.
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13
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Wang W, Duclot F, Groveman BR, Carrier N, Qiao H, Fang XQ, Wang H, Xin W, Jiang XH, Salter MW, Ding XS, Kabbaj M, Yu XM. Hippocampal protein kinase D1 is necessary for DHPG-induced learning and memory impairments in rats. PLoS One 2018; 13:e0195095. [PMID: 29614089 PMCID: PMC5882104 DOI: 10.1371/journal.pone.0195095] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2017] [Accepted: 03/18/2018] [Indexed: 11/18/2022] Open
Abstract
Background Understanding molecular mechanisms underlying the induction of learning and memory impairments remains a challenge. Recent investigations have shown that the activation of group I mGluRs (mGluR1 and mGluR5) in cultured hippocampal neurons by application of (S)-3,5-Dihydroxyphenylglycine (DHPG) causes the regulated internalization of N-methyl-D-aspartate receptors (NMDARs), which subsequently activates protein kinase D1 (PKD1). Through phosphorylating the C-terminals of the NMDAR GluN2 subunits, PKD1 down-regulates the activity of remaining (non-internalized) surface NMDARs. The knockdown of PKD1 does not affect the DHPG-induced inhibition of AMPA receptor-mediated miniature excitatory post-synaptic currents (mEPSCs) but prevents the DHPG-induced inhibition of NMDAR-mediated mEPSCs in vitro. Thus, we investigated the in vivo effects of bilateral infusions of DHPG into the hippocampal CA1 area of rats in the Morris water maze (MWM) and the novel object discrimination (NOD) tests. Methods A total of 300 adult male Sprague Dawley rats (250–280 g) were used for behavioral tests. One hundred ninety four were used in MWM test and the other 106 rats in the NOD test. Following one week of habituation to the vivarium, rats were bilaterally implanted under deep anesthesia with cannulas aimed at the CA1 area of the hippocampus (CA1 coordinates in mm from Bregma: AP -3.14; lateral +/-2; DV -3.0). Through implanted cannulas artificial cerebrospinal fluid (ACSF), the group1 mGluR antagonist 6-Methyl-2-(phenylethynyl)pyridine (MPEP), the dynamin-dependent internalization inhibitor Dynasore, or the PKD1 inhibitor CID755673 were infused into the bilateral hippocampal CA1 areas (2 μL per side, over 5 min). The effects of these infusions and the effects of PKD1 knockdown were examined in MWM or NOD test. Results DHPG infusion increased the latency to reach the platform in the MWM test and reduced the preference for the novel object in the NOD task. We found that the DHPG effects were dose-dependent and could be maintained for up to 2 days. Notably, these effects could be prevented by pre-infusion of the group1 mGluR antagonist MPEP, the dynamin-dependent internalization inhibitor Dynasore, the PKD1 inhibitor CID755673, or by PKD1 knockdown in the hippocampal CA1 area. Conclusion Altogether, these findings provide direct evidence that PKD1-mediated signaling may play a critical role in the induction of learning and memory impairments by DHPG infusion into the hippocampal CA1 area.
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Affiliation(s)
- Wei Wang
- Department of Neurology, the First Affiliated Hospital of Nanjing Medical University, Nanjing, People’s Republic of China
- BenQ Affiliated Hospital and Neurological Institute, Nanjing Medical University, Nanjing, People’s Republic of China
| | - Florian Duclot
- Department of Biomedical Sciences, Florida State University, Tallahassee, Florida, United States of America
| | - Bradley R. Groveman
- Department of Biomedical Sciences, Florida State University, Tallahassee, Florida, United States of America
| | - Nicole Carrier
- Department of Biomedical Sciences, Florida State University, Tallahassee, Florida, United States of America
| | - Haifa Qiao
- Department of Biomedical Sciences, Florida State University, Tallahassee, Florida, United States of America
| | - Xiao-Qian Fang
- Department of Biomedical Sciences, Florida State University, Tallahassee, Florida, United States of America
- Department of Biomedical Sciences, University of Texas Rio Grande Valley School of Medicine, Edinburg, Texas, United States of America
| | - Hui Wang
- Department of Biomedical Sciences, Florida State University, Tallahassee, Florida, United States of America
| | - Wenkuan Xin
- College of Pharmaceutical Sciences, Southwest University, Chongqing, People’s Republic of China
| | - Xing-Hong Jiang
- Department of Physiology and Neurobiology, Medical College of Soochow University, Suzhou, People’s Republic of China
| | - Michael W. Salter
- Program in Neuroscience and Mental Health, Hospital for Sick Children, University of Toronto, Toronto, Ontario, Canada
| | - Xin-Sheng Ding
- Department of Neurology, the First Affiliated Hospital of Nanjing Medical University, Nanjing, People’s Republic of China
- BenQ Affiliated Hospital and Neurological Institute, Nanjing Medical University, Nanjing, People’s Republic of China
- * E-mail: (XD); (MK); (XMY)
| | - Mohamed Kabbaj
- Department of Biomedical Sciences, Florida State University, Tallahassee, Florida, United States of America
- * E-mail: (XD); (MK); (XMY)
| | - Xian-Min Yu
- BenQ Affiliated Hospital and Neurological Institute, Nanjing Medical University, Nanjing, People’s Republic of China
- Department of Biomedical Sciences, Florida State University, Tallahassee, Florida, United States of America
- Department of Physiology and Neurobiology, Medical College of Soochow University, Suzhou, People’s Republic of China
- * E-mail: (XD); (MK); (XMY)
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14
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Yashiro S, Seki K. Association of social defeat stress-induced anhedonia-like symptoms with mGluR1-dependent decrease in membrane-bound AMPA-GluR1 in the mouse ventral midbrain. Stress 2017; 20:404-418. [PMID: 28554247 DOI: 10.1080/10253890.2017.1336534] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/23/2023] Open
Abstract
Anhedonia is a core symptom of social defeat stress (SDS)-induced depression associated with the reward system. We previously reported that decreased membrane-bound AMPA-GluR1 in the reward system is associated with lipopolysaccharide-induced anhedonia-like symptoms. Since group I metabotropic glutamate receptor (mGluR) activation reduces the surface density of GluR1, we examined whether group I mGluR-dependent decrease in membrane-bound GluR1 in the reward system is involved in SDS-induced anhedonia-like symptoms. Mice exposed to SDS for 4 consecutive days had markedly decreased membrane-bound GluR1 and GluR2 in the prefrontal cortex (PFC) and membrane-bound GluR1 in the ventral midbrain (VM) along with lower sucrose preference (SP). Intra-PFC injection of the group I mGluR agonist (S)-3,5-dihydroxyphenylglycine (DHPG; 100 μmol) demonstrated decrease in membrane-bound GluR1 and GluR2 in the PFC 2 and 24 h and membrane-bound GluR1 in the VM 24 h after injection. Moreover, intra-PFC injection of DHPG decreased SP only in the second 24-h (24-48 h) period. Conversely, intra-VM injection of DHPG decreased SP in both the first and second 24-h period and decreased membrane-bound GluR1 in the VM 2 and 24 h after injection. Pre-treatment with the mGluR1 antagonist JNJ16259685 (30 mg/kg, subcutaneous) prevented SDS-decreased SP and membrane-bound GluR1 in the VM. The mGluR5 antagonist 2-methyl-6-(phenylethynyl)pyridine (MPEP; 10 mg/kg, subcutaneous) prevented SDS-induced decrease in membrane-bound GluR1 and GluR2 in the PFC, whereas MPEP did not affect SDS-induced decrease in SP and membrane-bound GluR1 in the VM. These results suggest that mGluR1-mediated decrease in membrane-bound GluR1 in VM is involved in SDS-induced anhedonia-like symptoms.
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Affiliation(s)
- Sayori Yashiro
- a Department of Pharmacology, School of Pharmaceutical Science , Ohu University , Tomitamachi, Koriyama , Fukushima , Japan
| | - Kenjiro Seki
- a Department of Pharmacology, School of Pharmaceutical Science , Ohu University , Tomitamachi, Koriyama , Fukushima , Japan
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15
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Sánchez-Barrionuevo L, González-Benjumea A, Escobar-Niño A, García MT, López Ó, Maya I, Fernández-Bolaños JG, Cánovas D, Mellado E. A Straightforward Access to New Families of Lipophilic Polyphenols by Using Lipolytic Bacteria. PLoS One 2016; 11:e0166561. [PMID: 27855214 PMCID: PMC5113952 DOI: 10.1371/journal.pone.0166561] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2016] [Accepted: 10/30/2016] [Indexed: 11/18/2022] Open
Abstract
The chemical synthesis of new lipophilic polyphenols with improved properties presents technical difficulties. Here we describe the selection, isolation and identification of lipolytic bacteria from food-processing industrial wastes, and their use for tailoring a new set of compounds with great interest in the food industry. These bacteria were employed to produce lipolytic supernatants, which were applied without further purification as biocatalysts in the chemoselective and regioselective synthesis of lipophilic partially acetylated phenolic compounds derived from olive polyphenols. The chemoselectivity of polyphenols acylation/deacylation was analyzed, revealing the preference of the lipases for phenolic hydroxyl groups and phenolic esters. In addition, the alcoholysis of peracetylated 3,4-dihydroxyphenylglycol resulted in a series of lipophilic 2-alkoxy-2-(3,4-dihydroxyphenyl)ethyl acetate through an unexpected lipase-mediated etherification at the benzylic position. These new compounds are more lipophilic and retained their antioxidant properties. This approach can provide access to unprecedented derivatives of 3,4-dihydroxyphenylglycol with improved properties.
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Affiliation(s)
- Leyre Sánchez-Barrionuevo
- Department of Genetics, Faculty of Biology, University of Seville, Seville, Spain
- Department of Microbiology and Parasitology, Faculty of Pharmacy, University of Seville, Seville, Spain
| | | | - Almudena Escobar-Niño
- Department of Genetics, Faculty of Biology, University of Seville, Seville, Spain
- Department of Microbiology and Parasitology, Faculty of Pharmacy, University of Seville, Seville, Spain
| | - María Teresa García
- Department of Microbiology and Parasitology, Faculty of Pharmacy, University of Seville, Seville, Spain
| | - Óscar López
- Department of Organic Chemistry, Faculty of Chemistry, University of Seville, Seville, Spain
| | - Inés Maya
- Department of Organic Chemistry, Faculty of Chemistry, University of Seville, Seville, Spain
| | | | - David Cánovas
- Department of Genetics, Faculty of Biology, University of Seville, Seville, Spain
- * E-mail: (EM); (DC)
| | - Encarnación Mellado
- Department of Microbiology and Parasitology, Faculty of Pharmacy, University of Seville, Seville, Spain
- * E-mail: (EM); (DC)
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Dadak S, Bouquier N, Goyet E, Fagni L, Levenes C, Perroy J. mGlu1 receptor canonical signaling pathway contributes to the opening of the orphan GluD2 receptor. Neuropharmacology 2016; 115:92-99. [PMID: 27276689 DOI: 10.1016/j.neuropharm.2016.06.001] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2015] [Revised: 05/19/2016] [Accepted: 06/02/2016] [Indexed: 11/18/2022]
Abstract
The orphan Glutamate receptor Delta2 (GluD2) intrinsic ion channel activity is indirectly triggered by glutamate through stimulation of the metabotropic glutamate receptor 1 (mGlu1), in cerebellar Purkinje cells. However, the mechanisms of GluD2 ion channel opening are entirely unknown. In this work, we investigated the signaling pathways underlying the mGlu1-induced GluD2 current, performing whole-cell voltage-clamp recordings from mGlu1 and GluD2 transfected HEK293 cells. We show that the activation of GluD2 channels via DHPG-induced mGlu1 stimulation is Gαq-dependent. Moreover, inhibition of the downstream components of the mGlu1 canonical signaling pathway PLC and PKC with U73122 and GF109203X, respectively, strongly reduced the DHPG-induced GluD2 current. These results were further confirmed on endogenous receptors at the Parallel Fiber - Purkinje Cell cerebellar synapse, indicating that the opening of the GluD2 channel by mGlu1 receptor mobilizes the canonical Gq-PLC-PKC pathway. This article is part of the Special Issue entitled 'Metabotropic Glutamate Receptors, 5 years on'.
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Affiliation(s)
- Selma Dadak
- CNRS, UMR-5203, Institut de Génomique Fonctionnelle, Montpellier, F-34094, France; INSERM, U1191, Montpellier, F-34094, France; Université de Montpellier, UMR-5203, Montpellier, F-34094, France
| | - Nathalie Bouquier
- CNRS, UMR-5203, Institut de Génomique Fonctionnelle, Montpellier, F-34094, France; INSERM, U1191, Montpellier, F-34094, France; Université de Montpellier, UMR-5203, Montpellier, F-34094, France
| | - Elise Goyet
- CNRS, UMR-5203, Institut de Génomique Fonctionnelle, Montpellier, F-34094, France; INSERM, U1191, Montpellier, F-34094, France; Université de Montpellier, UMR-5203, Montpellier, F-34094, France
| | - Laurent Fagni
- CNRS, UMR-5203, Institut de Génomique Fonctionnelle, Montpellier, F-34094, France; INSERM, U1191, Montpellier, F-34094, France; Université de Montpellier, UMR-5203, Montpellier, F-34094, France
| | - Carole Levenes
- CNRS, UMR 8119 Neurophysics and Physiology Laboratory, Université Paris Descartes, Paris, France
| | - Julie Perroy
- CNRS, UMR-5203, Institut de Génomique Fonctionnelle, Montpellier, F-34094, France; INSERM, U1191, Montpellier, F-34094, France; Université de Montpellier, UMR-5203, Montpellier, F-34094, France.
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17
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Wennberg P, Boraxbekk CJ, Wheeler M, Howard B, Dempsey PC, Lambert G, Eikelis N, Larsen R, Sethi P, Occleston J, Hernestål-Boman J, Ellis KA, Owen N, Dunstan DW. Acute effects of breaking up prolonged sitting on fatigue and cognition: a pilot study. BMJ Open 2016; 6:e009630. [PMID: 26920441 PMCID: PMC4769400 DOI: 10.1136/bmjopen-2015-009630] [Citation(s) in RCA: 92] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
OBJECTIVES To compare the acute effects of uninterrupted sitting with sitting interrupted by brief bouts of light-intensity walking on self-reported fatigue, cognition, neuroendocrine biomarkers and cardiometabolic risk markers in overweight/obese adults. DESIGN Randomised two-condition crossover trial. SETTING Laboratory study conducted in Melbourne, Australia. PARTICIPANTS 19 overweight/obese adults (45-75 years). INTERVENTIONS After an initial 2 h period seated, participants consumed a meal-replacement beverage and completed (on 2 days separated by a 6-day washout period) each condition over the next 5 h: uninterrupted sitting (sedentary condition) or sitting with 3 min bouts of light-intensity walking every 30 min (active condition). PRIMARY OUTCOME MEASURES Self-reported fatigue, executive function and episodic memory at 0 h, 4 h and 7 h. SECONDARY OUTCOME MEASURES Neuroendocrine biomarkers and cardiometabolic risk markers (blood collections at 0 h, 4 h and 7 h, blood pressure and heart rate measured hourly and interstitial glucose measured using a continuous glucose monitoring system). RESULTS During the active condition, fatigue levels were lower at 4 h (-13.32 (95% CI -23.48 to -3.16)) and at 7 h (-10.73 (95% CI -20.89 to -0.58)) compared to the sedentary condition. Heart rate was higher at 4 h (4.47 (95% CI 8.37 to 0.58)) and at 7 h (4.32 (95% CI 8.21 to 0.42)) during the active condition compared to the sedentary condition. There were no significant differences between conditions by time for other variables. In the sedentary condition, changes in fatigue scores over time correlated with a decrease in heart rate and plasma dihydroxyphenylalanine (DOPA) and an increase in plasma dihydroxyphenylglycol (DHPG). CONCLUSIONS Interrupting prolonged sitting with light-intensity walking breaks may be an effective fatigue countermeasure acutely. Fatigue levels corresponded with the heart rate and neuroendocrine biomarker changes in uninterrupted sitting in this pilot study. Further research is needed to identify potential implications, particularly for the occupational health context. TRIAL REGISTRATION NUMBER ACTRN12613000137796; Results.
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Affiliation(s)
- Patrik Wennberg
- Department of Public Health and Clinical Medicine, Umeå University, Umeå, Sweden
| | | | - Michael Wheeler
- Baker IDI Heart and Diabetes Institute, Melbourne, Australia
- School of Sport Science, Exercise & Health, University of Western Australia, Perth, Australia
| | - Bethany Howard
- Baker IDI Heart and Diabetes Institute, Melbourne, Australia
- Central Clinical School, Monash University, Melbourne, Australia
| | - Paddy C Dempsey
- Baker IDI Heart and Diabetes Institute, Melbourne, Australia
- Central Clinical School, Monash University, Melbourne, Australia
| | - Gavin Lambert
- Baker IDI Heart and Diabetes Institute, Melbourne, Australia
- Central Clinical School, Monash University, Melbourne, Australia
| | - Nina Eikelis
- Baker IDI Heart and Diabetes Institute, Melbourne, Australia
| | - Robyn Larsen
- Baker IDI Heart and Diabetes Institute, Melbourne, Australia
| | - Parneet Sethi
- Baker IDI Heart and Diabetes Institute, Melbourne, Australia
| | | | | | - Kathryn A Ellis
- The Academic Unit for Psychiatry of Old Age, Department of Psychiatry, University of Melbourne, Melbourne, Australia
| | - Neville Owen
- Baker IDI Heart and Diabetes Institute, Melbourne, Australia
- Central Clinical School, Monash University, Melbourne, Australia
- School of Population Health, The University of Queensland, Brisbane, Australia
- Melbourne School of Population and Global Health, The University of Melbourne, Melbourne, Australia
| | - David W Dunstan
- Baker IDI Heart and Diabetes Institute, Melbourne, Australia
- School of Sport Science, Exercise & Health, University of Western Australia, Perth, Australia
- Central Clinical School, Monash University, Melbourne, Australia
- School of Population Health, The University of Queensland, Brisbane, Australia
- Melbourne School of Population and Global Health, The University of Melbourne, Melbourne, Australia
- School of Exercise & Nutrition Sciences, Deakin University, Melbourne, Australia
- Mary MacKillop Institute for Health Research, Australian Catholic University, Melbourne, Australia
- Department of Epidemiology and Preventive Medicine, Monash University, Melbourne, Australia
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18
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Imamura Y, Mizoguchi Y, Nabeta H, Matsushima J, Watanabe I, Kojima N, Kawashima T, Yamada S, Monji A. Belief in life after death, salivary 3-methoxy-4-hydroxyphenylglycol, and well-being among older people without cognitive impairment dwelling in rural Japan. Int J Geriatr Psychiatry 2015; 30:256-64. [PMID: 24760761 DOI: 10.1002/gps.4135] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/15/2014] [Revised: 03/26/2014] [Accepted: 03/27/2014] [Indexed: 11/07/2022]
Abstract
OBJECTIVES Research has found that spirituality/religiosity has a salutary association with mental/physical health. However, the association of belief in life after death with well-being has rarely been studied, and the same is true of its association with biological indices, such as monoamine transmitters. Therefore, we examined the associations between well-being and religiosity, salivary 3-methoxy-4-hydroxyphenylglycol (sMHPG), and demographic characteristics. METHODS The participants were 346 community-dwelling people, aged 65 years or older, without cognitive or mental deficits, in rural Japan. Measures of religiosity consisted of belief in life after death, attachment to life, and experiences related to death and religion. The measures were assessed by scales specifically suited for Japanese religious orientations. Participants' well-being was assessed by a life satisfaction scale containing two subscales. We also measured sMHPG, a major metabolite of noradrenaline that is thought to reflect certain psychological states, such as psychomotor retardation and effortful attention. RESULTS One subscale of life satisfaction was positively associated with belief in life after death and sMHPG, and the other life satisfaction subscale was positively associated with education and death/religion-related experiences (e.g., visiting family graves or loss of a friend). Gender differences were found in afterlife beliefs and each life satisfaction subscale. CONCLUSIONS These results suggest that religiosity, including belief in life after death and death/religion-related experiences, is salubriously associated with mental health among older people, especially women, living in rural Japan. The basal level of sMHPG was positively associated with life satisfaction, but not with belief in life after death.
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Affiliation(s)
- Yoshiomi Imamura
- Department of Psychiatry, Faculty of Medicine, Saga University, Saga, Japan; Institute of Comparative Studies of International Cultures and Societies, Kurume University, Kurume, Fukuoka, Japan
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Aparicio-Soto M, Sánchez-Fidalgo S, González-Benjumea A, Maya I, Fernández-Bolaños JG, Alarcón-de-la-Lastra C. Naturally occurring hydroxytyrosol derivatives: hydroxytyrosyl acetate and 3,4-dihydroxyphenylglycol modulate inflammatory response in murine peritoneal macrophages. Potential utility as new dietary supplements. J Agric Food Chem 2015; 63:836-846. [PMID: 25526103 DOI: 10.1021/jf503357s] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
This work evaluated the effects of extra virgin olive oil (EVOO) phenols, hydroxytyrosyl acetate (2) and 3,4-dihydroxyphenylglycol (3), as well as two new acyl derivatives of 3, 4-(1,2-di(butanoyloxy)ethyl)benzene-1,2-diol (7) and 4-(1,2-di(lauroyloxy)ethyl)benzene-1,2-diol (8), on LPS-stimulated murine peritoneal macrophages in comparison with hydroxytyrosol (HTy, 1). Compounds 2, 3, 7, and 8 showed a strong reactive oxygen species (ROS)-scavenging activity, reducing significantly nitrite levels with a significant decrease on iNOS expression [2 (50 μM, 0.44 ± 0.03; 100 μM, 0.44 ± 0.01; p < 0.01); 3 (50 μM, 0.37 ± 0.03; 100 μM, 0.37 ± 0.01; p < 0.001); 7 (50 μM, 0.45 ± 0.06; p < 0.01)] . However, only 2 and 3 down-regulated COX-2 expression [2 (50 μM, 0.72 ± 0.04, p < 0.05; 100 μM, 0.54 ± 0.06, p < 0.01); 3 (50 μM, 0.56 ± 0.05, p < 0.05; 100 μM, 0.37 ± 0.04; p < 0.001)] and prevented IKBα degradation [2 (100 μM, 1.63 ± 0.14, p < 0.01); 3 (100 μM, 1.82 ± 0.09; p < 0.01)] ; the diacylated compounds 7 and 8 showed worse anti-inflammatory activity than the parent 3. In conclusion, 2 and 3 phenolic derivatives could play an important role in the anti-inflammatory effect of EVOO. The implication of this study for the nutrition and general health of the population rests in the possible use of natural HTy derivatives with better hydrophilic/lipophilic balance, thus improving its pharmacodynamic and pharmacokinetic profiles, as new dietary supplements in foods.
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Affiliation(s)
- Marina Aparicio-Soto
- Department of Pharmacology, Faculty of Pharmacy, University of Seville , Profesor García González Street 2, 41012 Seville, Spain
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Kubota H, Nagao S, Obata K, Hirono M. mGluR1-mediated excitation of cerebellar GABAergic interneurons requires both G protein-dependent and Src-ERK1/2-dependent signaling pathways. PLoS One 2014; 9:e106316. [PMID: 25181481 PMCID: PMC4152260 DOI: 10.1371/journal.pone.0106316] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2013] [Accepted: 08/05/2014] [Indexed: 12/26/2022] Open
Abstract
Stimulation of type I metabotropic glutamate receptors (mGluR1/5) in several neuronal types induces slow excitatory responses through activation of transient receptor potential canonical (TRPC) channels. GABAergic cerebellar molecular layer interneurons (MLIs) modulate firing patterns of Purkinje cells (PCs), which play a key role in cerebellar information processing. MLIs express mGluR1, and activation of mGluR1 induces an inward current, but its precise intracellular signaling pathways are unknown. We found that mGluR1 activation facilitated spontaneous firing of mouse cerebellar MLIs through an inward current mediated by TRPC1 channels. This mGluR1-mediated inward current depends on both G protein-dependent and -independent pathways. The nonselective protein tyrosine kinase inhibitors genistein and AG490 as well as the selective extracellular signal-regulated kinase 1/2 (ERK1/2) inhibitors PD98059 and SL327 suppressed the mGluR1-mediated current responses. Following G protein blockade, the residual mGluR1-mediated inward current was significantly reduced by the selective Src tyrosine kinase inhibitor PP2. In contrast to cerebellar PCs, GABAB receptor activation in MLIs did not alter the mGluR1-mediated inward current, suggesting that there is no cross-talk between mGluR1 and GABAB receptors in MLIs. Thus, activation of mGluR1 facilitates firing of MLIs through the TRPC1-mediated inward current, which depends on not only G protein-dependent but also Src–ERK1/2-dependent signaling pathways, and consequently depresses the excitability of cerebellar PCs.
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Affiliation(s)
- Hideo Kubota
- Materials Management, Medical Hospital, Tokyo Medical and Dental University (TMDU), Bunkyo, Tokyo, Japan
- * E-mail: (HK); (MH)
| | - Soichi Nagao
- Laboratory for Motor Learning Control, RIKEN Brain Science Institute, Wako, Saitama, Japan
| | - Kunihiko Obata
- Obata Research Unit, RIKEN Brain Science Institute, Wako, Saitama, Japan
| | - Moritoshi Hirono
- Laboratory for Motor Learning Control, RIKEN Brain Science Institute, Wako, Saitama, Japan
- Obata Research Unit, RIKEN Brain Science Institute, Wako, Saitama, Japan
- * E-mail: (HK); (MH)
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Straznicky NE, Grima MT, Sari CI, Eikelis N, Lambert GW, Nestel PJ, Karapanagiotidis S, Wong C, Richards K, Marusic P, Dixon JB, Schlaich MP, Lambert EA. A randomized controlled trial of the effects of pioglitazone treatment on sympathetic nervous system activity and cardiovascular function in obese subjects with metabolic syndrome. J Clin Endocrinol Metab 2014; 99:E1701-7. [PMID: 24937541 DOI: 10.1210/jc.2014-1976] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
CONTEXT Insulin resistance and sympathetic nervous system overactivity are closely associated and contribute to cardiovascular risk. OBJECTIVE The objective of the study was to test the hypotheses that pharmacological improvement in insulin sensitivity would (1) attenuate sympathetic neural drive and (2) enhance neuronal norepinephrine uptake. PARTICIPANTS AND METHODS A randomized, double-blind trial was conducted in 42 obese, unmedicated individuals with metabolic syndrome (mean age 56 ± 1 y, body mass index 34 ± 0.6 kg/m(2)) who received 12 weeks of pioglitazone (PIO; 15 mg for 6 wk, then 30 mg daily) or matched placebo. Clinical measurements included whole-body norepinephrine kinetics [spillover rate, plasma clearance, and the steady state ratio of tritiated 3,4-dihydroxyphenylglycol to tritiated norepinephrine ([(3)H]-DHPG to [(3)H]-NE) as an index of neuronal uptake-1], muscle sympathetic nerve activity, spontaneous baroreflex sensitivity, euglycemic hyperinsulinemic clamp, oral glucose tolerance test, ambulatory blood pressure, and Doppler echocardiography. RESULTS PIO treatment increased glucose uptake by 35% and was accompanied by significant reductions in diastolic blood pressure and improved left ventricular diastolic and endothelial function. Resting muscle sympathetic nerve activity burst frequency decreased by -6 ± 3 burst/min compared with baseline (P = .03), but the magnitude of change was not different from placebo (P = .89). Norepinephrine spillover and clearance rates and baroreflex sensitivity were unchanged. Post hoc subgroup analyses revealed an 83% increase in [(3)H]-DHPG to [(3)H]-NE ratio in hyperinsulinemic (P = .04) but not normoinsulinemic subjects (time × group interaction, P = .045). Change in [(3)H]-DHPG to [(3)H]-NE ratio correlated with improvements in diastolic blood pressure (r = -0.67, P = .002), the ratio of early (E) to late (A) peak transmitral diastolic inflow velocity (r = 0.62, P = .008), E wave deceleration time (r = -0.48, P = .05), and Δinsulin area under the curve0-120 during the oral glucose tolerance test (r = -0.42, P = .08). CONCLUSIONS Compared with placebo, PIO does not affect resting sympathetic drive or norepinephrine disposition in obese subjects with metabolic syndrome. Treatment induced changes in the [(3)H]-DHPG to [(3)H]-NE ratio related to reduction in hyperinsulinemia and improvements in diastolic function.
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Affiliation(s)
- Nora E Straznicky
- Laboratories of Human Neurotransmitters (N.E.S., M.T.G., C.L.S., N.E., G.W.L., K.R., J.B.D., E.A.L.), Cardiovascular Nutrition (P.J.N.), and Neurovascular Hypertension and Kidney Disease (P.M., M.P.S.) and Alfred Baker Medical Unit (S.K., C.W.), Baker IDI Heart and Diabetes Institute, Melbourne, Victoria 8008, Australia; Faculty of Medicine, Nursing, and Health Sciences (G.W.L., M.P.S.) and the Departments of Physiology (E.A.L.) and Primary Health Care (J.B.D.), Monash University, Melbourne, Victoria 3800, Australia; and the Department of Physiology (E.A.L.), University of Melbourne, Melbourne 3010, Australia
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Straznicky NE, Lambert EA, Grima MT, Eikelis N, Richards K, Nestel PJ, Dawood T, Masuo K, Sari CI, Dixon JB, Esler MD, Paul E, Schlaich MP, Lambert GW. The effects of dietary weight loss on indices of norepinephrine turnover: modulatory influence of hyperinsulinemia. Obesity (Silver Spring) 2014; 22:652-62. [PMID: 23997009 DOI: 10.1002/oby.20614] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/15/2013] [Revised: 08/19/2013] [Accepted: 08/22/2013] [Indexed: 11/11/2022]
Abstract
OBJECTIVES This study was conducted to examine (1) the effects of dietary weight loss on indices of norepinephrine (NE) turnover and (2) whether baseline hyperinsulinemia modulates sympathetic neural adaptations. METHODS Obese individuals aged 56 ± 1 year, BMI 32.5 ± 0.4 kg/m(2) , with metabolic syndrome, underwent a 12-week hypocaloric diet (HCD, n = 39) or no treatment (n = 26). Neurochemical measurements comprised arterial dihydroxyphenylalanine (DOPA), 3,4-dihydroxyphenylglycol (DHPG), and NE concentrations, the steady-state ratio of [3H]-DHPG to [3H]-NE, as an index of neuronal uptake, and calculated whole-body plasma NE clearance and spillover rates. RESULTS Body weight decreased by -7.4 ± 0.5% in HCD group (P < 0.001) and was accompanied by reductions in DOPA, NE, and DHPG averaging -14 ± 5% (P = 0.001), -23 ± 4% (P <0.001), and -5 ± 4% (P = 0.03), respectively. NE spillover rate decreased by -88 ± 39 ng/min (P = 0.01), whereas neuronal uptake and NE plasma clearance were unchanged. Despite similar weight loss, hyperinsulinemic subjects exhibited greater reductions in NE and NE spillover rate, compared to normoinsulinemic subjects (group by time interaction P < 0.05). CONCLUSIONS Weight loss is associated with down-regulation of sympathetic nervous activity but no overall alteration in disposition indices. Hyperinsulinemic subjects derive a greater sympathoinhibitory benefit during weight loss.
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Affiliation(s)
- Nora E Straznicky
- Laboratories of Human Neurotransmitters, Baker IDI Heart & Diabetes Institute, Melbourne, Victoria, Australia
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Sakuragi S, Tominaga-Yoshino K, Ogura A. Involvement of TrkB- and p75(NTR)-signaling pathways in two contrasting forms of long-lasting synaptic plasticity. Sci Rep 2013; 3:3185. [PMID: 24212565 PMCID: PMC3822391 DOI: 10.1038/srep03185] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2013] [Accepted: 10/25/2013] [Indexed: 12/17/2022] Open
Abstract
The repetition of experience is often necessary to establish long-lasting memory. However, the cellular mechanisms underlying this repetition-dependent consolidation of memory remain unclear. We previously observed in organotypic slice cultures of the rodent hippocampus that repeated inductions of long-term potentiation (LTP) led to a slowly developing long-lasting synaptic enhancement coupled with synaptogenesis. We also reported that repeated inductions of long-term depression (LTD) produced a long-lasting synaptic suppression coupled with synapse elimination. We proposed these phenomena as useful in vitro models for analyzing repetition-dependent consolidation. Here, we hypothesized that the enhancement and suppression are mediated by the brain-derived neurotrophic factor (BDNF)-TrkB signaling pathway and the proBDNF-p75(NTR) pathway, respectively. When we masked the respective pathways, reversals of the enhancement and suppression resulted. These results suggest the alternative activation of the p75(NTR) pathway by BDNF under TrkB-masking conditions and of the TrkB pathway by proBDNF under p75(NTR)-masking conditions, thus supporting the aforementioned hypothesis.
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Affiliation(s)
- Shigeo Sakuragi
- Department of Neuroscience, Osaka University Graduate School of Frontier Biosciences, Suita 565-0871 Osaka, Japan
| | - Keiko Tominaga-Yoshino
- Department of Neuroscience, Osaka University Graduate School of Frontier Biosciences, Suita 565-0871 Osaka, Japan
| | - Akihiko Ogura
- Department of Neuroscience, Osaka University Graduate School of Frontier Biosciences, Suita 565-0871 Osaka, Japan
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Rudenko A, Dawlaty MM, Seo J, Cheng AW, Meng J, Le T, Faull KF, Jaenisch R, Tsai LH. Tet1 is critical for neuronal activity-regulated gene expression and memory extinction. Neuron 2013; 79:1109-1122. [PMID: 24050401 PMCID: PMC4543319 DOI: 10.1016/j.neuron.2013.08.003] [Citation(s) in RCA: 320] [Impact Index Per Article: 29.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/23/2013] [Indexed: 12/22/2022]
Abstract
The ten-eleven translocation (Tet) family of methylcytosine dioxygenases catalyze oxidation of 5-methylcytosine (5mC) to 5-hydroxymethylcytosine (5hmC) and promote DNA demethylation. Despite the abundance of 5hmC and Tet proteins in the brain, little is known about the functions of the neuronal Tet enzymes. Here, we analyzed Tet1 knockout mice (Tet1KO) and found downregulation of multiple neuronal activity-regulated genes, including Npas4, c-Fos, and Arc. Furthermore, Tet1KO animals exhibited abnormal hippocampal long-term depression and impaired memory extinction. Analysis of the key regulatory gene, Npas4, indicated that its promoter region, containing multiple CpG dinucleotides, is hypermethylated in both naive Tet1KO mice and after extinction training. Such hypermethylation may account for the diminished expression of Npas4 itself and its downstream targets, impairing transcriptional programs underlying cognitive processes. In summary, we show that neuronal Tet1 regulates normal DNA methylation levels, expression of activity-regulated genes, synaptic plasticity, and memory extinction.
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Affiliation(s)
- Andrii Rudenko
- The Picower Institute for Learning and Memory, 77 Massachusetts Avenue, Cambridge, MA, 02139
- Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA, 02139
- Howard Hughes Medical Institute, Cambridge, MA
| | | | - Jinsoo Seo
- The Picower Institute for Learning and Memory, 77 Massachusetts Avenue, Cambridge, MA, 02139
- Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA, 02139
- Howard Hughes Medical Institute, Cambridge, MA
| | - Albert W. Cheng
- Whitehead Institute for Biomedical Research, Cambridge, MA
- Computational and Systems Biology Program, Cambridge, MA 02142, USA
| | - Jia Meng
- The Picower Institute for Learning and Memory, 77 Massachusetts Avenue, Cambridge, MA, 02139
| | - Thuc Le
- Pasarow Mass Spectrometry Laboratory, Department of Psychiatry and Biobehavioral Sciences and Semel Institute for Neuroscience and Human Behavior, David Geffen School of Medicine, University of California, Los Angeles, CA 90095, USA
| | - Kym F. Faull
- Pasarow Mass Spectrometry Laboratory, Department of Psychiatry and Biobehavioral Sciences and Semel Institute for Neuroscience and Human Behavior, David Geffen School of Medicine, University of California, Los Angeles, CA 90095, USA
| | - Rudolf Jaenisch
- Whitehead Institute for Biomedical Research, Cambridge, MA
- Department of Biology Massachusetts Institute of Technology, Cambridge, MA 02142, USA
| | - Li-Huei Tsai
- The Picower Institute for Learning and Memory, 77 Massachusetts Avenue, Cambridge, MA, 02139
- Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA, 02139
- Howard Hughes Medical Institute, Cambridge, MA
- Stanley Center for Psychiatric Research, Broad Institute, Cambridge, MA
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Moussouttas M, Bhatnager M, Huynh TT, Lai EW, Khoury J, Dombrowski K, DeCaro M, Pacak K. Association between sympathetic response, neurogenic cardiomyopathy, and venous thromboembolization in patients with primary subarachnoid hemorrhage. Acta Neurochir (Wien) 2013; 155:1501-10. [PMID: 23636336 DOI: 10.1007/s00701-013-1725-x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2012] [Accepted: 04/12/2013] [Indexed: 11/28/2022]
Abstract
INTRODUCTION Sympathetic activation promotes hemostasis, and subarachnoid hemorrhage (SAH) is associated with pronounced sympathetic activation. This investigation will assess whether catecholaminergic activity relates to venous thrombotic events in patients with acute SAH. METHODS Observational study of consecutive SAH grade 3-5 patients requiring ventriculostomy insertion who did not undergo open surgical treatment of cerebral aneurysm. Cerebrospinal fluid (CSF) samples were obtained within 48 h of hemorrhage for assay of catecholamines, which were related to occurrence of deep venous thrombosis (DVT) and pulmonary embolization (PE). RESULTS Of the 92 subjects, mean age was 57 years, 76% were female, and 57% Caucasian; 11% experienced lower extremity (LE) DVT, 12% developed upper extremity (UE) or LE DVT, and 23% developed any DVT/PE. Mean time to occurrence of UE/LE DVT was 7.8 days (+/-5.9 days), and mean time to development of PE was 8.8 days (+/-5.4 days). In hazards analysis models, independent predictors of LE DVT included neurogenic cardiomyopathy (NC) [HR 4.97 (95%CI 1.32-18.7)], norepinephrine/3,4-dihydroxyphenylglycol ratio (NE/DHPG) [3.81 (2.04-7.14)], NE [5.91 (2.14-16.3)], and dopamine (DA) [2.27 (1.38-3.72)]. Predictors of UE/LE DVT included NC [5.78 (1.70-19.7)], cerebral infarction [4.01 (1.18-13.7)], NE [3.58 (1.40-9.19)], NE/DHPG [3.38 (1.80-6.33)] and DA [2.01 (1.20-3.35)]. Predictors of DVT/PE included Hunt-Hess grade (H/H) [3.02 (1.19-7.66)], NE [2.56 (1.23-5.37)] and 3,4-dihydroxyphenylalanine (DOPA) [3.49 (1.01-12.0)]. CONCLUSIONS In severe SAH, central sympathetic activity and clinical manifestations of (nor)adrenergic activity relate to the development of venous thromboemboli. Catecholamine activation may promote hemostasis, or may represent a biomarker for venous thromboses.
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Affiliation(s)
- Michael Moussouttas
- Neurocritical Care Division, Capital Institute for Neuroscience, Capital Regional Medical Center, 750 Brunswick Avenue, Trenton, NJ 08638, USA.
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Lama-Muñoz A, Rodríguez-Gutiérrez G, Rubio-Senent F, Palacios-Díaz R, Fernández-Bolaños J. A study of the precursors of the natural antioxidant phenol 3,4-dihydroxyphenylglycol in olive oil waste. Food Chem 2013; 140:154-60. [PMID: 23578627 DOI: 10.1016/j.foodchem.2013.02.063] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2012] [Revised: 01/30/2013] [Accepted: 02/11/2013] [Indexed: 01/03/2023]
Abstract
3,4-Dihydroxyphenylglycol (DHPG) is a potent antioxidant recently found in the free form in olive oil and table olives. DHPG can be recovered from olive oil solid waste by a hydrothermal treatment. It was observed that an increase in the concentration of DHPG occurred when alperujo aqueous extracts were subjected to mild thermal conditions (post-treatment). This fact indicates that certain solubilized compounds or precursors containing DHPG which is released with the post-treatment. In the present study, the precursors of DHPG were identified and characterized after extraction from alperujo using thermal treatment and purification by fractionation on Amberlite® XAD16 polyamide and semi-preparative reverse-phase HPLC columns. Their structures were elucidated using HPLC coupled to diode array detector (DAD) and electrospray ionization mass spectrometry (ESI-MS). The results identified three compounds as precursors, and their structures can be attributed to the diastereoisomeric forms of the two β-hydroxy derivatives of verbascoside and isoverbascoside (β-hydroxyacteoside and β-hydroxyisoacteoside), and 2″-hydroxyoleuropein, all of which contain a DHPG moiety, potentially explaining the increases in the concentration of this phenolic compound in olive oil waste.
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Affiliation(s)
- Antonio Lama-Muñoz
- Departamento de Biotecnología de Alimentos, Instituto de la Grasa (Consejo Superior de Investigaciones Científicas, CSIC), Avda. Padre García Tejero, 4, 41012 Seville, Spain
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Abstract
Drug addiction is driven, in part, by powerful drug-related memories. Deficits in social life, particularly during adolescence, increase addiction vulnerability. Social isolation in rodents has been used extensively to model the effects of deficient social experience, yet its impact on learning and memory processes underlying addiction remains elusive. Here, we show that social isolation of rats during a critical period of adolescence (postnatal days 21-42) enhances long-term potentiation of NMDA receptor (NMDAR)-mediated glutamatergic transmission in the ventral tegmental area (VTA). This enhancement, which is caused by an increase in metabotropic glutamate receptor-dependent Ca(2+) signaling, cannot be reversed by subsequent resocialization. Notably, memories of amphetamine- and ethanol-paired contextual stimuli are acquired faster and, once acquired, amphetamine-associated contextual memory is more resistant to extinction in socially isolated rats. We propose that NMDAR plasticity in the VTA may represent a neural substrate by which early life deficits in social experience increase addiction vulnerability.
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Affiliation(s)
- Leslie R. Whitaker
- Waggoner Center for Alcohol and Addiction Research, University of Texas at Austin, 2400 Speedway, Austin, TX, 78712, USA
- Section of Neurobiology, University of Texas at Austin, 2400 Speedway, Austin, TX, 78712, USA
- Institute for Neuroscience, University of Texas at Austin, 2400 Speedway, Austin, TX, 78712, USA
| | - Mickael Degoulet
- Waggoner Center for Alcohol and Addiction Research, University of Texas at Austin, 2400 Speedway, Austin, TX, 78712, USA
- Section of Neurobiology, University of Texas at Austin, 2400 Speedway, Austin, TX, 78712, USA
- Institute for Neuroscience, University of Texas at Austin, 2400 Speedway, Austin, TX, 78712, USA
| | - Hitoshi Morikawa
- Waggoner Center for Alcohol and Addiction Research, University of Texas at Austin, 2400 Speedway, Austin, TX, 78712, USA
- Section of Neurobiology, University of Texas at Austin, 2400 Speedway, Austin, TX, 78712, USA
- Institute for Neuroscience, University of Texas at Austin, 2400 Speedway, Austin, TX, 78712, USA
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Gregg LC, Jung KM, Spradley JM, Nyilas R, Suplita RL, Zimmer A, Watanabe M, Mackie K, Katona I, Piomelli D, Hohmann AG. Activation of type 5 metabotropic glutamate receptors and diacylglycerol lipase-α initiates 2-arachidonoylglycerol formation and endocannabinoid-mediated analgesia. J Neurosci 2012; 32:9457-68. [PMID: 22787031 PMCID: PMC3652685 DOI: 10.1523/jneurosci.0013-12.2012] [Citation(s) in RCA: 64] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2011] [Revised: 05/11/2012] [Accepted: 05/17/2012] [Indexed: 11/21/2022] Open
Abstract
Acute stress reduces pain sensitivity by engaging an endocannabinoid signaling circuit in the midbrain. The neural mechanisms governing this process and molecular identity of the endocannabinoid substance(s) involved are unknown. We combined behavior, pharmacology, immunohistochemistry, RNA interference, quantitative RT-PCR, enzyme assays, and lipidomic analyses of endocannabinoid content to uncover the role of the endocannabinoid 2-arachidonoyl-sn-glycerol (2-AG) in controlling pain sensitivity in vivo. Here, we show that footshock stress produces antinociception in rats by activating type 5 metabotropic glutamate receptors (mGlu(5)) in the dorsolateral periaqueductal gray (dlPAG) and mobilizing 2-AG. Stimulation of mGlu(5) in the dlPAG with DHPG [(S)-3,5-dihydroxyphenylglycine] triggered 2-AG formation and enhanced stress-dependent antinociception through a mechanism dependent upon both postsynaptic diacylglycerol lipase (DGL) activity, which releases 2-AG, and presynaptic CB(1) cannabinoid receptors. Pharmacological blockade of DGL activity in the dlPAG with RHC80267 [1,6-bis(cyclohexyloximinocarbonylamino)hexane] and (-)-tetrahydrolipstatin (THL), which inhibit activity of DGL-α and DGL-β isoforms, suppressed stress-induced antinociception. Inhibition of DGL activity in the dlPAG with THL selectively decreased accumulation of 2-AG without altering levels of anandamide. The putative 2-AG-synthesizing enzyme DGL-α colocalized with mGlu(5) at postsynaptic sites of the dlPAG, whereas CB(1) was confined to presynaptic terminals, consistent with a role for 2-AG as a retrograde signaling messenger. Finally, virally mediated silencing of DGL-α, but not DGL-β, transcription in the dlPAG mimicked effects of DGL inhibition in suppressing both endocannabinoid-mediated stress antinociception and 2-AG formation. The results indicate that activation of the postsynaptic mGlu(5)-DGL-α cascade triggers retrograde 2-AG signaling in vivo. This pathway is required for endocannabinoid-mediated stress-induced analgesia.
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Affiliation(s)
- Laura C. Gregg
- Neuroscience Program, Biomedical and Health Sciences Institute, and
| | - Kwang-Mook Jung
- Department of Pharmacology, University of California, Irvine, Irvine, California 92697
| | | | - Rita Nyilas
- Institute of Experimental Medicine, Hungarian Academy of Sciences, H-1083 Budapest, Hungary
| | - Richard L. Suplita
- Psychology Department, University of Georgia, Athens, Georgia 30602-3013
| | - Andreas Zimmer
- Insitute of Molecular Psychiatry, University of Bonn, 53105 Bonn, Germany
| | - Masahiko Watanabe
- Department of Anatomy, Hokkaido University School of Medicine, Sapporo 060-8638, Japan
| | - Ken Mackie
- Department of Psychological and Brain Sciences, Indiana University, Bloomington, Indiana 47405-2204, and
| | - István Katona
- Institute of Experimental Medicine, Hungarian Academy of Sciences, H-1083 Budapest, Hungary
| | - Daniele Piomelli
- Department of Pharmacology, University of California, Irvine, Irvine, California 92697
- Unit of Drug Discovery and Development, Italian Institute of Technology, 16163 Genoa, Italy
| | - Andrea G. Hohmann
- Neuroscience Program, Biomedical and Health Sciences Institute, and
- Psychology Department, University of Georgia, Athens, Georgia 30602-3013
- Department of Psychological and Brain Sciences, Indiana University, Bloomington, Indiana 47405-2204, and
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29
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Sun L, Gu L, Wang S, Yuan J, Yang H, Zhu J, Zhang H. N-acetylcysteine protects against apoptosis through modulation of group I metabotropic glutamate receptor activity. PLoS One 2012; 7:e32503. [PMID: 22442667 PMCID: PMC3307713 DOI: 10.1371/journal.pone.0032503] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2011] [Accepted: 01/31/2012] [Indexed: 01/27/2023] Open
Abstract
The activation of group I metabotropic glutamate receptor (group I mGlus) has been shown to produce neuroprotective or neurotoxic effects. In this study, we investigated the effects of N-acetylcysteine (NAC), a precursor of the antioxidant glutathione, on group I mGlus activation in apoptosis of glial C6 and MN9D cell lines, and a rat model of Parkinson's disease (PD). We demonstrated that NAC protected against apoptosis through modulation of group I mGlus activity. In glial C6 cells, NAC promoted phosphorylation of ERK induced by (s)-3,5- dihydroxy-phenylglycine (DHPG), an agonist of group I mGlus. NAC enhanced the group I mGlus-mediated protection from staurosporine (STS)-induced apoptosis following DHPG treatment. Moreover, in rotenone-treated MN9D cells and PD rat model, NAC protected against group I mGlus-induced toxicity by compromising the decrease in phosphorylation of ERK, phosphorylation or expression level of TH. Furthermore, the results showed that NAC prohibited the level of ROS and oxidation of cellular GSH/GSSG (Eh) accompanied by activated group I mGlus in the experimental models. Our results suggest that NAC might act as a regulator of group I mGlus-mediated activities in both neuroprotection and neurotoxicity via reducing the oxidative stress, eventually to protect cell survival. The study also suggests that NAC might be a potential therapeutics targeting for group I mGlus activation in the treatment of PD.
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Affiliation(s)
- Lili Sun
- Department of Cell Biology, Key Laboratory for Neurodegenerative Disease, Ministry of Education, Capital Medical University, Beijing, China
| | - Li Gu
- Department of Cell Biology, Key Laboratory for Neurodegenerative Disease, Ministry of Education, Capital Medical University, Beijing, China
| | - Shuting Wang
- Department of Cell Biology, Key Laboratory for Neurodegenerative Disease, Ministry of Education, Capital Medical University, Beijing, China
| | - Jifang Yuan
- Department of Cell Biology, Key Laboratory for Neurodegenerative Disease, Ministry of Education, Capital Medical University, Beijing, China
| | - Huimin Yang
- Department of Cell Biology, Key Laboratory for Neurodegenerative Disease, Ministry of Education, Capital Medical University, Beijing, China
| | - Jiawei Zhu
- Department of Cell Biology, Key Laboratory for Neurodegenerative Disease, Ministry of Education, Capital Medical University, Beijing, China
| | - Hong Zhang
- Department of Cell Biology, Key Laboratory for Neurodegenerative Disease, Ministry of Education, Capital Medical University, Beijing, China
- Department of Neurobiology, Key Laboratory for Neurodegenerative Disease, Ministry of Education, Capital Medical University, Beijing, China
- * E-mail:
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30
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Ji G, Neugebauer V. Pain-related deactivation of medial prefrontal cortical neurons involves mGluR1 and GABA(A) receptors. J Neurophysiol 2011; 106:2642-52. [PMID: 21880942 PMCID: PMC3214095 DOI: 10.1152/jn.00461.2011] [Citation(s) in RCA: 123] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2011] [Accepted: 08/29/2011] [Indexed: 11/22/2022] Open
Abstract
Pain-related hyperactivity in the amygdala leads to deactivation of the medial prefrontal cortex (mPFC) and decision-making deficits. The mechanisms of pain-related inhibition of the mPFC are not yet known. Here, we used extracellular single-unit recordings of prelimbic mPFC neurons to determine the role of GABA(A) receptors and metabotropic glutamate receptor (mGluR) subtypes, mGluR1 and mGluR5, in pain-related activity changes of mPFC neurons. Background and evoked activity of mPFC neurons decreased after arthritis induction. To determine pain-related changes, the same neuron was recorded continuously before and after induction of arthritis in one knee joint by intra-articular injection of kaolin/carrageenan. Stereotaxic administration of a GABA(A) receptor antagonist {[R-(R*,S*)]-5-(6,8-dihydro-8-oxofuro[3,4-e]-1,3-benzodioxol-6-yl)-5,6,7,8-tetrahydro-6,6-dimethyl-1,3-dioxolo[4,5-g]isoquinolinium iodide (bicuculline)} into the mPFC by microdialysis reversed pain-related inhibition, whereas offsite injections into the adjacent anterior cingulate cortex had no or opposite effects on prelimbic mPFC neurons. A selective mGluR1/5 agonist [(S)-3,5-dihydroxyphenylglycine (DHPG)] inhibited background and evoked activity under normal conditions through a GABAergic mechanism, because the inhibitory effect was blocked with bicuculline. In the arthritis pain state, DHPG, alone or in the presence of bicuculline, had no effect. Consistent with the involvement of mGluR1 in pain-related inhibition of the mPFC, a selective mGluR1 antagonist [(S)-(+)-α-amino-4-carboxy-2-methylbenzeneacetic acid] reversed the pain-related decrease of background and evoked activity of mPFC neurons in arthritis, whereas a selective mGluR5 antagonist [2-methyl-6-(phenylethynyl)pyridine hydrochloride] had no effect. The mGluR antagonists had no effect under normal conditions. We interpret our data to suggest that pain-related inhibition of mPFC neurons in the arthritis model depends on mGluR1-mediated endogenous activation of GABA(A) receptors. Exogenous activation of mGluR1/5 produces GABAergic inhibition under normal conditions. Restoring normal activity in the mPFC may be a therapeutic strategy to improve cognitive deficits associated with persistent pain.
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Affiliation(s)
- Guangchen Ji
- Dept. of Neuroscience and Cell Biology, The Univ. of Texas Medical Branch, 301 Univ. Blvd., Galveston, TX 77555-1069, USA
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31
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Yang K, Takeuchi K, Wei F, Dubner R, Ren K. Activation of group I mGlu receptors contributes to facilitation of NMDA receptor membrane current in spinal dorsal horn neurons after hind paw inflammation in rats. Eur J Pharmacol 2011; 670:509-18. [PMID: 21951968 DOI: 10.1016/j.ejphar.2011.09.009] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2011] [Revised: 08/10/2011] [Accepted: 09/10/2011] [Indexed: 10/17/2022]
Abstract
The interaction between the group I metabotropic glutamate (mGlu) receptors and N-methyl-D-aspartate (NMDA) receptors plays a critical role in spinal hyperexcitability and hyperalgesia. The cellular mechanisms underlying this interaction remain unknown. Utilizing an ex vivo spinal slice preparation from young adult rats, we investigated the group I mGlu receptor modulation of NMDA receptor-mediated current in superficial dorsal horn neurons by patch clamp recording after complete Freund's adjuvant (CFA)-induced hind paw inflammation. We show that NMDA receptor-mediated dorsal root stimulation-evoked EPSC (eEPSC) and NMDA-induced current was enhanced in the inflamed rats, compared to naïve rats and this effect was attenuated by AIDA (1 mM), a group I mGlu receptor antagonist. There were also increases in the frequency and amplitude of miniature excitatory postsynaptic currents in the presence of tetrodotoxin, suggesting enhanced presynaptic glutamate release probability and postsynaptic membrane responsiveness in inflamed rats. DHPG (10 μM), a selective group I mGlu receptor agonist, further facilitated NMDA receptor-mediated eEPSC and NMDA-induced current in inflamed rats. The DHPG-produced facilitation of NMDA-induced current was blocked by intracellular dialysis of GDP-beta-S (1 mM), a G protein antagonist, and BAPTA (15 mM), an intracellular calcium chelating agent; and by pretreatment with U73,122 (10 μM), a PLC inhibitor, or 2-APB (100 μM), an IP₃-receptor antagonist. These findings support the hypothesis that signal transduction coupling between group I mGlu receptors and NMDA receptors underlies the activation of NMDA receptors in spinal hyperexcitability and hyperalgesia.
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Affiliation(s)
- Kun Yang
- Department of Neural and Pain Sciences, School of Dentistry and Program in Neuroscience, University of Maryland, Baltimore, MD 21201, USA
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32
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Rendu F, Peoc’h K, Berlin I, Thomas D, Launay JM. Smoking related diseases: the central role of monoamine oxidase. Int J Environ Res Public Health 2011; 8:136-47. [PMID: 21318020 PMCID: PMC3037066 DOI: 10.3390/ijerph8010136] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/03/2010] [Revised: 12/24/2010] [Accepted: 01/06/2011] [Indexed: 01/24/2023]
Abstract
Smoking is a major risk factor of morbidity and mortality. It is well established that monoamine oxidase (MAO) activity is decreased in smokers. Serotonin (5-HT), a major substrate for MAO that circulates as a reserve pool stored in platelets, is a marker of platelet activation. We recently reported that smoking durably modifies the platelet 5-HT/MAO system by inducing a demethylation of the MAO gene promoter resulting in high MAO protein concentration persisting more than ten years after quitting smoking. The present data enlarges the results to another MAO substrate, norepinephrine (NE), further confirming the central role of MAO in tobacco use-induced diseases. Thus, MAO could be a readily accessible and helpful marker in the risk evaluation of smoking-related diseases, from cardiovascular and pulmonary diseases to depression, anxiety and cancer. The present review implements the new finding of epigenetic regulation of MAO and suggests that smoking-induced MAO demethylation can be considered as a hallmark of smoking-related cancers similarly to other aberrant DNA methylations.
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Affiliation(s)
- Francine Rendu
- UMRS 956 (Génétique, Pharmacologie et Physiopathologie des maladies cardiovasculaires), Faculté de Médecine Pitié-Salpétrière, Université Pierre et Marie Curie, 91 Bd de l’hôpital, 75634 Paris cedex 13, France
- Author to whom correspondence should be addressed; E-Mail: ; Tel.: +33-(0)140-779-907; Fax: +33-(0)140-779-645
| | - Katell Peoc’h
- Service de Biochimie et Biologie Moléculaire, Assistance Publique des Hôpitaux de Paris (AP-HP), and Biologie cellulaire, Faculté de Pharmacie, Université Paris-Descartes, Hôpital Lariboisière 2 rue Ambroise Paré, 75475 Paris cedex 10, France; E-Mails: (K.P.); (J.-M.L.)
| | - Ivan Berlin
- Pharmacologie clinique du tabagisme; Inserm U894, Faculté de Médecine Pitié-Salpétrière, Université Pierre et Marie Curie and Service de pharmacologie, Hôpital Pitié-Salpétrière, 47 Bd de l'Hôpital, 75651 Paris cedex13, France; E-Mail:
| | - Daniel Thomas
- Institut de Cardiologie, Hôpital Pitié-Salpétrière, 47 Bd de l'Hôpital, 75651 Paris cedex13, France; E-Mail:
| | - Jean-Marie Launay
- Service de Biochimie et Biologie Moléculaire, Assistance Publique des Hôpitaux de Paris (AP-HP), and Biologie cellulaire, Faculté de Pharmacie, Université Paris-Descartes, Hôpital Lariboisière 2 rue Ambroise Paré, 75475 Paris cedex 10, France; E-Mails: (K.P.); (J.-M.L.)
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33
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Montoya A, Escobar R, García-Polavieja MJ, Lachno DR, Alda JÁ, Artigas J, Cardo E, García M, Gastaminza X, Gilaberte I. Changes of urine dihydroxyphenylglycol to norepinephrine ratio in children with attention-deficit hyperactivity disorder (ADHD) treated with atomoxetine. J Child Neurol 2011; 26:31-6. [PMID: 20525942 DOI: 10.1177/0883073810371981] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
This study investigated changes in the urine dihydroxyphenylglycol to norepinephrine ratio in patients with attention-deficit hyperactivity disorder (ADHD) treated with atomoxetine. The possible relationship with clinical response was also explored. Newly ADHD diagnosed, treatment-naïve children or adolescents were double-blindly randomized (2:1) to atomoxetine (n = 28) or placebo (n = 13). The dihydroxyphenylglycol to norepinephrine ratio decreased in both groups, showing significantly greater changes with atomoxetine than with placebo at week 6 (-42% versus -14%; P = .001), when dosed at 1.2 mg/kg/day, than at week 2 (-20% versus -2%; P = .118) with a dose of 0.5 mg/kg/day. Although the significant dihydroxyphenylglycol to norepinephrine ratio decrease with atomoxetine indicated norepinephrine transporter blockade, no association with ADHD clinical response (ADHD Rating Scale-IV-Parent:Investigator) was found. Therefore, dihydroxyphenylglycol to norepinephrine ratio might be a useful pharmacodynamic/pharmacokinetic biomarker, although not sufficiently sensitive to predict clinical efficacy. It remains a possibility that this ratio might have value to facilitate personalized atomoxetine pharmacotherapy in ADHD patients.
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Park JY, Remy S, Varela J, Cooper DC, Chung S, Kang HW, Lee JH, Spruston N. A post-burst after depolarization is mediated by group i metabotropic glutamate receptor-dependent upregulation of Ca(v)2.3 R-type calcium channels in CA1 pyramidal neurons. PLoS Biol 2010; 8:e1000534. [PMID: 21103408 PMCID: PMC2982802 DOI: 10.1371/journal.pbio.1000534] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2010] [Accepted: 09/21/2010] [Indexed: 12/20/2022] Open
Abstract
The excitability of hippocampal pyramidal neurons is regulated by activation of metabotropic glutamate receptors, an effect that is mediated by modulation of R-type calcium channels. Activation of group I metabotropic glutamate receptors (subtypes mGluR1 and mGluR5) regulates neural activity in a variety of ways. In CA1 pyramidal neurons, activation of group I mGluRs eliminates the post-burst afterhyperpolarization (AHP) and produces an afterdepolarization (ADP) in its place. Here we show that upregulation of Cav2.3 R-type calcium channels is responsible for a component of the ADP lasting several hundred milliseconds. This medium-duration ADP is rapidly and reversibly induced by activation of mGluR5 and requires activation of phospholipase C (PLC) and release of calcium from internal stores. Effects of mGluR activation on subthreshold membrane potential changes are negligible but are large following action potential firing. Furthermore, the medium ADP exhibits a biphasic activity dependence consisting of short-term facilitation and longer-term inhibition. These findings suggest that mGluRs may dramatically alter the firing of CA1 pyramidal neurons via a complex, activity-dependent modulation of Cav2.3 R-type channels that are activated during spiking at physiologically relevant rates and patterns. The hippocampus is an essential structure in the brain for the formation of new declarative memories. Understanding the cellular basis of memory formation, storage, and recall in the hippocampus requires a knowledge of the properties of the relevant neurons and how they are modulated by activity in the neural circuit. For many years, we have known that various chemical neurotransmitters can modulate the electrical excitability of neurons in the hippocampus. Here, we report new experiments to reveal how the chemical neurotransmitter glutamate increases neuronal excitability. The effect we study is the conversion of the afterhyperpolarization (a cellular consequence of firing an action potential) to an afterdepolarization. We identified the metabotropic glutamate receptors involved in this conversion (receptors called mGluR1 and mGluR5) as well as the final target of modulation (R-type calcium channels composed of Cav2.3 subunits), which cause the neurons to exhibit altered excitability in the presence of glutamate. We also determined some of the intermediate steps between activation of the glutamate receptors and modulation of the calcium channels responsible for the change in excitability, offering further mechanistic insight into how synaptic transmission can regulate cellular and network activity.
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Affiliation(s)
- Jin-Yong Park
- Department of Neurobiology and Physiology, Northwestern University, Evanston, Illinois, United States of America
| | - Stefan Remy
- Department of Neurobiology and Physiology, Northwestern University, Evanston, Illinois, United States of America
| | - Juan Varela
- Department of Neurobiology and Physiology, Northwestern University, Evanston, Illinois, United States of America
| | - Donald C. Cooper
- Department of Neurobiology and Physiology, Northwestern University, Evanston, Illinois, United States of America
| | - Sungkwon Chung
- Department of Neurobiology and Physiology, Northwestern University, Evanston, Illinois, United States of America
| | - Ho-Won Kang
- Department of Life Science and Basic Science Institute for Cell Damage Control, Sogang University, Seoul, Korea
| | - Jung-Ha Lee
- Department of Life Science and Basic Science Institute for Cell Damage Control, Sogang University, Seoul, Korea
| | - Nelson Spruston
- Department of Neurobiology and Physiology, Northwestern University, Evanston, Illinois, United States of America
- * E-mail:
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35
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Kao DI, Aldridge GM, Weiler IJ, Greenough WT. Altered mRNA transport, docking, and protein translation in neurons lacking fragile X mental retardation protein. Proc Natl Acad Sci U S A 2010; 107:15601-6. [PMID: 20713728 PMCID: PMC2932564 DOI: 10.1073/pnas.1010564107] [Citation(s) in RCA: 111] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
Abstract
Fragile X syndrome is caused by the absence of functional fragile X mental retardation protein (FMRP), an RNA binding protein. The molecular mechanism of aberrant protein synthesis in fmr1 KO mice is closely associated with the role of FMRP in mRNA transport, delivery, and local protein synthesis. We show that GFP-labeled Fmr1 and CaMKIIalpha mRNAs undergo decelerated motion at 0-40 min after group I mGluR stimulation, and later recover at 40-60 min. Then we investigate targeting of mRNAs associated with FMRP after neuronal stimulation. We find that FMRP is synthesized closely adjacent to stimulated mGluR5 receptors. Moreover, in WT neurons, CaMKIIalpha mRNA can be delivered and translated in dendritic spines within 10 min in response to group I mGluR stimulation, whereas KO neurons fail to show this response. These data suggest that FMRP can mediate spatial mRNA delivery for local protein synthesis in response to synaptic stimulation.
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MESH Headings
- Animals
- Calcium-Calmodulin-Dependent Protein Kinase Type 2/genetics
- Calcium-Calmodulin-Dependent Protein Kinase Type 2/metabolism
- Cells, Cultured
- Dendrites/metabolism
- Fragile X Mental Retardation Protein/genetics
- Fragile X Mental Retardation Protein/metabolism
- Green Fluorescent Proteins/genetics
- Green Fluorescent Proteins/metabolism
- Hippocampus/cytology
- In Situ Hybridization, Fluorescence
- Kinetics
- Methoxyhydroxyphenylglycol/analogs & derivatives
- Methoxyhydroxyphenylglycol/pharmacology
- Mice
- Mice, Inbred C57BL
- Mice, Knockout
- Microscopy, Fluorescence
- Neurons/cytology
- Neurons/drug effects
- Neurons/metabolism
- Protein Binding
- Protein Biosynthesis
- RNA Transport
- RNA, Messenger/genetics
- RNA, Messenger/metabolism
- Receptor, Metabotropic Glutamate 5
- Receptors, Metabotropic Glutamate/genetics
- Receptors, Metabotropic Glutamate/metabolism
- Time Factors
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Affiliation(s)
- Der-I Kao
- Department of Cell and Developmental Biology
- Beckman Institute
| | | | | | - William T. Greenough
- Department of Cell and Developmental Biology
- Beckman Institute
- Neuroscience Program, and
- Departments of Psychology and Psychiatry, University of Illinois at Urbana–Champaign, Urbana, IL 61801
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36
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Gross C, Nakamoto M, Yao X, Chan CB, Yim SY, Ye K, Warren ST, Bassell GJ. Excess phosphoinositide 3-kinase subunit synthesis and activity as a novel therapeutic target in fragile X syndrome. J Neurosci 2010; 30:10624-38. [PMID: 20702695 PMCID: PMC2924772 DOI: 10.1523/jneurosci.0402-10.2010] [Citation(s) in RCA: 208] [Impact Index Per Article: 14.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2010] [Revised: 05/09/2010] [Accepted: 06/11/2010] [Indexed: 01/30/2023] Open
Abstract
Fragile X syndrome (FXS) is an inherited neurologic disease caused by loss of fragile X mental retardation protein (FMRP), which is hypothesized to mediate negative regulation of mRNA translation at synapses. A prominent feature of FXS animal models is exaggerated signaling through group 1 metabotropic glutamate receptors (gp1 mGluRs), and therapeutic strategies to treat FXS are targeted mainly at gp1 mGluRs. Recent studies, however, indicate that a variety of receptor-mediated signal transduction pathways are dysregulated in FXS, suggesting that FMRP acts on a common downstream signaling molecule. Here, we show that deficiency of FMRP results in excess activity of phosphoinositide 3-kinase (PI3K), a downstream signaling molecule of many cell surface receptors. In Fmr1 knock-out neurons, excess synaptic PI3K activity can be reduced by perturbation of gp1 mGluR-mediated signaling. Remarkably, increased PI3K activity was also observed in FMRP-deficient non-neuronal cells in the absence of gp1 mGluRs. Here, we show that FMRP regulates the synthesis and synaptic localization of p110beta, the catalytic subunit of PI3K. In wild type, gp1 mGluR activation induces p110beta translation, p110beta protein expression, and PI3K activity. In contrast, both p110beta protein synthesis and PI3K activity are elevated and insensitive to gp1 mGluR stimulation in Fmr1 knock-out. This suggests that dysregulated PI3K signaling may underlie the synaptic impairments in FXS. In support of this hypothesis, we show that PI3K antagonists rescue three FXS-associated phenotypes: dysregulated synaptic protein synthesis, excess AMPA receptor internalization, and increased spine density. Targeting excessive PI3K activity might thus be a potent therapeutic strategy for FXS.
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Affiliation(s)
| | | | | | | | | | | | | | - Gary J. Bassell
- Departments of Cell Biology
- Neurology, Emory University School of Medicine, Atlanta, Georgia 30322
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37
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Shinoda Y, Tanaka T, Tominaga-Yoshino K, Ogura A. Persistent synapse loss induced by repetitive LTD in developing rat hippocampal neurons. PLoS One 2010; 5:e10390. [PMID: 20436928 PMCID: PMC2861005 DOI: 10.1371/journal.pone.0010390] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2010] [Accepted: 04/08/2010] [Indexed: 11/19/2022] Open
Abstract
Synaptic pruning is a physiological event that eliminates excessive or inappropriate synapses to form proper synaptic connections during development of neurons. Appropriate synaptic pruning is required for normal neural development. However, the mechanism of synaptic pruning is not fully understood. Strength of synaptic activity under competitive circumstances is thought to act as a selective force for synaptic pruning. Long-term depression (LTD) is a synaptic plasticity showing persistent decreased synaptic efficacy, which is accompanied by morphological changes of dendritic spines including transient retraction. Repetitive induction of LTD has been shown to cause persistent loss of synapses in mature neurons. Here, we show that multiple, but not single, induction of LTD caused a persistent reduction in the number of dendritic synapses in cultured rat developing hippocampal neurons. When LTD was induced in 14 days in vitro cultures by application of (RS)-3,5-dihydroxyphenylglycine (DHPG), a group I metabotropic glutamate receptor (mGluR) agonist, and repeated three times with a one day interval, there was a significant decrease in the number of dendritic synapses. This effect continued up to at least two weeks after the triple LTD induction. The persistent reduction in synapse number occurred in the proximal dendrites, but not the distal dendrites, and was prevented by simultaneous application of the group I/II mGluR antagonist (S)-a-methyl-4-carboxyphenylglycine (MCPG). In conclusion, we found that repetitive LTD induction in developing neurons elicits synaptic pruning and contributes to activity-dependent regulation of synapse number in rat hippocampal neurons.
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Affiliation(s)
- Yo Shinoda
- Laboratory for Molecular Neurogenesis, RIKEN Brain Science Institute, Wako, Saitama, Japan.
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38
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Naumenko SE, Latysheva TV, Gilinskiĭ MA. [Ischemic preconditioning and metabolism of myocardial adrenaline]. Kardiologiia 2010; 50:48-52. [PMID: 20659027] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
We implanted under urethane narcosis microdialysis probes into myocardium of Wistar rats. In experimental group we used ischemic preconditioning. After this left descending coronary artery was occluded for 60 minutes and then reperfused for 60 min. In control group prolonged occlusion was preceded by 30 min of rest. Significant elevation of noradrenaline concentration in myocardial interstitium was noted at 20th and 10th minutes of testing ischemia in experimental and control groups respectively. From 20th minute to the termination of occlusion noradrenaline concentration in myocardial in animals of control group was significantly higher than that in preconditioned animals. Concentration of dihydroxyphenylglycol in interstitium reflecting noradrenaline metabolism in axoplasm fell during ischemia and rose when reperfusion was started. Elevation of dihydroxyphenylglycol was statistically significant compared with both baseline level and control (p<0.005) practically at all stages of reperfusion. Thus ischemic preconditioning inhibits effectively noradrenaline accumulation in myocardial interstitium during prolonged ischemia. After ischemic preconditioning normal mechanism of noradrenaline reuptake functions longer however because of impaired storage in vesicles substantial part of noradrenaline remains in free state in axoplasm to be subjected to deamination with participation of monoamine oxidase.
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Rodríguez G, Lama A, Jaramillo S, Fuentes-Alventosa JM, Guillén R, Jiménez-Araujo A, Rodríguez-Arcos R, Fernández-Bolaños J. 3,4-Dihydroxyphenylglycol (DHPG): an important phenolic compound present in natural table olives. J Agric Food Chem 2009; 57:6298-6304. [PMID: 19545148 DOI: 10.1021/jf803512r] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
The presence of 3,4-dihydroxyphenylglycol (DHPG) was studied in 32 samples and 10 different cultivars of natural table olives, using an accurate method to avoid wrong quantification. Hydroxytyrosol (HT), tyrosol, and verbascoside were also quantified, as these four compounds comprise the majority of the chromatographic profile. Analyses were carried out by HPLC-DAD-UV after extraction of all phenolics, and hydroxytyrosol was the major component in nearly all samples. High levels of DHPG (up to 368 mg/kg of dry weight) were found in the pulp of natural black olives independent of cultivar and processing method, similar to its concentration in the brine in almost all of the samples. The presented data for this antioxidant indicate that natural table olives are a rich source of DHPG and hydroxytyrosol, compounds with interesting nutritional and antioxidant properties.
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Affiliation(s)
- Guillermo Rodríguez
- Departamento de Biotecnología de los Alimentos, Instituto de la Grasa (CSIC), Apartado 1078, 41012 Sevilla, Spain
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Mitchell DA, Lambert G, Secher NH, Raven PB, van Lieshout J, Esler MD. Jugular venous overflow of noradrenaline from the brain: a neurochemical indicator of cerebrovascular sympathetic nerve activity in humans. J Physiol 2009; 587:2589-97. [PMID: 19403604 PMCID: PMC2714023 DOI: 10.1113/jphysiol.2008.167999] [Citation(s) in RCA: 61] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2008] [Accepted: 04/08/2009] [Indexed: 11/08/2022] Open
Abstract
A novel neurochemical method was applied for studying the activity of sympathetic nerves in the human cerebral vascular system. The aim was to investigate whether noradrenaline plasma kinetic measurements made with internal jugular venous sampling reflect cerebrovascular sympathetic activity. A database was assembled of fifty-six healthy subjects in whom total body noradrenaline spillover (indicative of whole body sympathetic nervous activity), brain noradrenaline spillover and brain lipophlic noradrenaline metabolite (3,4-dihydroxyphenolglycol (DHPG) and 3-methoxy-4-hydroxyphenylglycol (MHPG)) overflow rates were measured. These measurements were also made following ganglion blockade (trimethaphan, n = 6), central sympathetic inhibition (clonidine, n = 4) and neuronal noradrenaline uptake blockade (desipramine, n = 13) and in a group of patients (n = 9) with pure autonomic failure (PAF). The mean brain noradrenline spillover and brain noradrenaline metabolite overflow in healthy subjects were 12.5 +/- 1.8, and 186.4 +/- 25 ng min(-1), respectively, with unilateral jugular venous sampling for both. Total body noradrenaline spillover was 605.8 ng min(-1) +/- 34.4 ng min(-1). As expected, trimethaphan infusion lowered brain noradrenaline spillover (P = 0.03), but perhaps surprisingly increased jugular overflow of brain metabolites (P = 0.01). Suppression of sympathetic nervous outflow with clonidine lowered brain noradrenaline spillover (P = 0.004), without changing brain metabolite overflow (P = 0.3). Neuronal noradrenaline uptake block with desipramine lowered the transcranial plasma extraction of tritiated noradrenaline (P = 0.001). The PAF patients had 77% lower brain noradrenaline spillover than healthy recruits (P = 0.06), indicating that in them sympathetic nerve degeneration extended to the cerebral circulation, but metabolites overflow was similar to healthy subjects (P = 0.3). The invariable discordance between noradrenline spillover and noradrenaline metabolite overflow from the brain under these different circumstances indicates that the two measures arise from different sources, i.e. noradrenaline spillover originates from the cerebral vasculature outside the blood-brain barrier, and the noradrenaline metabolites originate primarily from brain noradrenergic neurons. We suggest that measurements of transcranial plasma noradrenaline spillover have utility as a method for assessing the sympathetic nerve activity of the cerebral vasculature.
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Affiliation(s)
- David A Mitchell
- Human Neurotransmitter Laboratory, Baker Medical Research Institute, Prahran, Victoria, Australia.
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Goldstein DS, Holmes C, Axelrod FB. Plasma catechols in familial dysautonomia: a long-term follow-up study. Neurochem Res 2008; 33:1889-93. [PMID: 18357519 DOI: 10.1007/s11064-008-9662-4] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2008] [Accepted: 03/10/2008] [Indexed: 11/25/2022]
Abstract
This study tested whether familial dysautonomia (FD) involves progressive loss of noradrenergic nerves. Plasma levels of catechols, including dihydroxyphenylglycol (DHPG), norepinephrine (NE), dopamine (DA), and DOPA, were measured in 7 adult patients with FD and 50 healthy control subjects. FD patients were re-tested after a mean follow-up period of 13 years. Compared to controls, FD patients had low plasma levels of DHPG (P < 0.001), high DOPA and DA levels (P = 0.01, P = 0.0002), and high NE:DHPG (P < 0.0001), DA:NE (P = 0.0003), and DOPA:DHPG (P < 0.0001) ratios. At follow-up there were no changes in plasma levels of individual catechols; however, there were further increases in DOPA:DHPG ratios (mean 24 +/- 7%, P = 0.01). In FD, plasma catechol profiles are sufficiently stable, at least over a decade, to be used as a biomarker of disease involvement. An increasing DOPA:DHPG ratio suggests slight but consistent, progressive loss of noradrenergic neurons.
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Affiliation(s)
- David S Goldstein
- Clinical Neurocardiology Section, National Institute of Neurological Disorders and Stroke, NIH, Building 10 Room 6N252, 10 Center Drive MSC-1620, Bethesda, MD 20892-1620, USA.
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Abstract
BACKGROUND Menkes disease is a fatal neurodegenerative disorder of infancy caused by diverse mutations in a copper-transport gene, ATP7A. Early treatment with copper injections may prevent death and illness, but presymptomatic detection is hindered by the inadequate sensitivity and specificity of diagnostic tests. Exploiting the deficiency of a copper enzyme, dopamine-beta-hydroxylase, we prospectively evaluated the diagnostic usefulness of plasma neurochemical levels, assessed the clinical effect of early detection, and investigated the molecular bases for treatment outcomes. METHODS Between May 1997 and July 2005, we measured plasma dopamine, norepinephrine, dihydroxyphenylacetic acid, and dihydroxyphenylglycol in 81 infants at risk. In 12 newborns who met the eligibility criteria and began copper-replacement therapy within 22 days after birth, we tracked survival and neurodevelopment longitudinally for 1.5 to 8 years. We characterized ATP7A mutations using yeast complementation, reverse-transcriptase-polymerase-chain-reaction analysis, and immunohistochemical analysis. RESULTS Of 81 infants at risk, 46 had abnormal neurochemical findings indicating low dopamine-beta-hydroxylase activity. On the basis of longitudinal follow-up, patients were classified as affected or unaffected by Menkes disease, and the neurochemical profiles were shown to have high sensitivity and specificity for detecting disease. Among 12 newborns with positive screening tests who were treated early with copper, survival at a median follow-up of 4.6 years was 92%, as compared with 13% at a median follow-up of 1.8 years for a historical control group of 15 late-diagnosis and late-treatment patients. Two of the 12 patients had normal neurodevelopment and brain myelination; 1 of these patients had a mutation that complemented a Saccharomyces cerevisiae copper-transport mutation, indicating partial ATPase activity, and the other had a mutation that allowed some correct ATP7A splicing. CONCLUSIONS Neonatal diagnosis of Menkes disease by plasma neurochemical measurements and early treatment with copper may improve clinical outcomes. Affected newborns who have mutations that do not completely abrogate ATP7A function may be especially responsive to early copper treatment. (ClinicalTrials.gov number, NCT00001262.)
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Affiliation(s)
- Stephen G Kaler
- Unit on Pediatric Genetics, Program in Molecular Medicine, National Institute of Child Health and Human Development, National Institutes of Health, Bldg. 10, Rm. 5-2571, 10 Center Dr., MSC 1832, Bethesda, MD 20892-1832,
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Meurs A, Clinckers R, Ebinger G, Michotte Y, Smolders I. Seizure activity and changes in hippocampal extracellular glutamate, GABA, dopamine and serotonin. Epilepsy Res 2007; 78:50-9. [PMID: 18054462 DOI: 10.1016/j.eplepsyres.2007.10.007] [Citation(s) in RCA: 88] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2007] [Revised: 10/08/2007] [Accepted: 10/18/2007] [Indexed: 12/28/2022]
Abstract
Increases in hippocampal extracellular neurotransmitter levels have consistently been observed during temporal lobe seizures in humans, but animal studies on this subject have yielded conflicting results. Our aim was to better characterise the relationship between seizure activity and changes in hippocampal glutamate, GABA, dopamine and serotonin by comparing three limbic seizure models which differ only in the pharmacological mechanism used to induce seizures. Seizures were evoked in freely moving rats by intrahippocampal microperfusion, via a microdialysis probe, of the muscarinic receptor agonist pilocarpine (10mM), GABA(A) receptor antagonist picrotoxin (100microM) or group I metabotropic glutamate receptor agonist (R,S)-3,5-dihydroxyphenylglycine (DHPG) (1mM). Seizure-related behavioural changes were scored and hippocampal extracellular glutamate, GABA, dopamine and serotonin concentrations were monitored. Seizures were of comparable severity in all groups. During seizures, hippocampal glutamate, GABA and dopamine concentrations increased in all groups. Glutamate increases were significantly higher in the picrotoxin group. Hippocampal serotonin concentration increased following pilocarpine and picrotoxin, but not DHPG. Our results suggest a direct relationship between seizure activity and increased hippocampal extracellular concentrations of glutamate, GABA and dopamine, but not serotonin. The fact that picrotoxin induces seizures by disinhibition, rather than direct excitation, may account for the larger glutamate increases in this group.
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Kishida I, Aklillu E, Kawanishi C, Bertilsson L, Agren H. Monoamine metabolites level in CSF is related to the 5-HTT gene polymorphism in treatment-resistant depression. Neuropsychopharmacology 2007; 32:2143-51. [PMID: 17299512 DOI: 10.1038/sj.npp.1301336] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
The serotonin (5-hydroxytryptamine) transporter (5-HTT) is considered to affect the pathogenesis of mood disorders. Large number of genetic association studies between 5-HTT functional polymorphisms and vulnerability of mood disorders and therapeutic response to antidepressants has been carried out. We investigated the influence of 5-HTT-linked polymorphic region (5-HTTLPR) and 5-HTT 17 bp variable number of tandem repeat polymorphism (5-HTTVNTR) polymorphisms on concentrations of monoamine metabolites in cerebrospinal fluid (CSF) among treatment-resistant patients with mood disorders. Subjects were 119 Swedish patients with persistent mood disorders and 141 healthy subjects. In 112 of these patients, we measured 5-hydroxyindoleacetic acid (5-HIAA), homovanillic acid (HVA), and 3-methoxy-4-hydroxyphenylglycol in CSF. Genotyping for 5-HTT polymorphisms from genomic DNA was carried out by PCR. There was no significant difference in allele/genotype frequency between patients and healthy subjects. In patients with mood disorders, we found significant difference in mean 5-HIAA concentration between 5-HTTLPR genotypes (p=0.03). Although the 5-HIAA concentration showed a tendency to be higher in short (S) carriers than in non-S carriers of the 5-HTTLPR in patients (p=0.06), when considering patients with major depressive disorder (MDD), the 5-HIAA concentration was significantly higher among S carriers than among non-S carriers (p=0.02). Moreover, the 5-HIAA concentration was higher in S/S subjects compared to long (L)/L (p=0.0001) and L/S (p=0.002) subjects in patients with MDD. Similarly, there was higher HVA concentration in S/S subjects compared to L/L (p=0.002) and L/S subjects (p=0.002). There was no effect of 5-HTTVNTR. Our findings show that the 5-HTTLPR polymorphism affects 5-HIAA and HVA concentrations among treatment-resistant patients with mood disorders.
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Affiliation(s)
- Ikuko Kishida
- Division of Clinical Pharmacology, Department of Laboratory Medicine, Karolinska Institutet, Karolinska University Hospital Huddinge,C-168,SE-141 86 Stockholm, Sweden
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Kumar A, Foster TC. Shift in induction mechanisms underlies an age-dependent increase in DHPG-induced synaptic depression at CA3 CA1 synapses. J Neurophysiol 2007; 98:2729-36. [PMID: 17898145 DOI: 10.1152/jn.00514.2007] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
Several forms of log-term synaptic plasticity have been identified and the mechanisms for induction and expression of synaptic modifications change over development and maturation. The present study examines age-related changes in the induction of group I metabotropic receptor selective agonist (R,S)-3,5-dihydroxyphenylglycine (DHPG) induced long-term synaptic depression (DHPG-LTD) at CA3-CA1 synapses. The results demonstrate that the magnitude of DHPG-LTD is enhanced in male aged Fischer 344 rats compared with young adults. The role of mGluR1 in the induction of DHPG-LTD was increased with advanced age and, in contrast to young adults, induction involved a significant contribution of NMDA receptors and L-type Ca(2+) channels. Moreover, the protein tyrosine phosphatase inhibitor sodium orthovanadate significantly attenuated DHPG-LTD only in young adults. The expression of DHPG-LTD in aged animals was dependent on protein synthesis and the enhanced expression was associated with an increase in paired-pulse facilitation. The results provide evidence that DHPG-LTD is one of the few forms of synaptic plasticity that increases with advanced age and suggest that DHPG-LTD may contribute to age-related changes in hippocampal function.
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Affiliation(s)
- Ashok Kumar
- Department of Neuroscience, McKnight Brain Institute, University of Florida, PO Box 100244, Gainesville, FL 32610-0244, USA
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Abstract
We have explored the potential involvement of the three main classes of metabotropic glutamate receptor in the modulation of a spinal locomotor network using tadpoles of the anuran amphibian Xenopus laevis. Selective activation of group I receptors in Xenopus embryos and young larvae using the general group I agonist DHPG [(S)-3,5-dihyroxyphenylglycine] significantly increased the frequency of swimming and the number of spontaneously occurring swimming episodes, as monitored by extracellular recordings from ventral roots. Group I receptor activation was without significant effect on the duration or amplitude of motor bursts, the duration of swimming episodes, or the head-to-tail delay in the propagation of swimming activity. Activation of either group II or group III receptors, however, following bath applications of the specific agonists APDC [(2R,4R)-aminopyrrolidine-2,4-dicarboxylic acid] and L-AP4 (L-2-amino-4-phosphonobutanoate), respectively, produced a net inhibitory effect on many of the parameters of fictive swimming at both developmental stages, including a reduction in swimming frequency and episode duration, along with a significant reduction in motor burst amplitude and duration in larval animals only. Applications of selective antagonists provide evidence for activation of all three groups during swimming. The group II and III antagonists EGLU (1-ethyl-2-benzimidazolinone) and MAP4 [(S)-2-amino-2-methyl-4-phosphonobutanoate], respectively, increased, while group I antagonists, CPCCOEt and MPEP, decreased swim frequency. Our findings thus provide evidence for the presence and endogenous activation of three classes of metabotropic glutamate receptor which may function as an intrinsic modulatory control system during fictive swimming in Xenopus tadpoles.
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Affiliation(s)
- Rebecca J Chapman
- School of Biology, Bute Medical Buildings, University of St. Andrews, St. Andrews, Fife KY16 9TS, UK
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Dewing P, Boulware MI, Sinchak K, Christensen A, Mermelstein PG, Micevych P. Membrane estrogen receptor-alpha interactions with metabotropic glutamate receptor 1a modulate female sexual receptivity in rats. J Neurosci 2007; 27:9294-300. [PMID: 17728443 PMCID: PMC2904398 DOI: 10.1523/jneurosci.0592-07.2007] [Citation(s) in RCA: 182] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
In rats, female sexual behavior is regulated by a well defined limbic-hypothalamic circuit that integrates sensory and hormonal information. Estradiol activation of this circuit results in mu-opioid receptor (MOR) internalization in the medial preoptic nucleus, an important step for full expression of sexual receptivity. Estradiol acts through both membrane and intracellular receptors to influence neuronal activity and behavior, yet the mechanism(s) and physiological significance of estradiol-mediated membrane responses in vivo have remained elusive. Recent in vitro evidence found that stimulation of membrane-associated estrogen receptor-alpha (ER alpha) led to activation of metabotropic glutamate receptor 1a (mGluR1a). Furthermore, mGluR1a signaling was responsible for the observed downstream effects of estradiol. Here we present data that show that ER alpha and mGluR1a directly interact to mediate a rapid estradiol-induced activation of MOR in the medial preoptic nucleus, leading to female sexual receptivity. In addition, blockade of mGluR1a in the arcuate nucleus of the hypothalamus resulted in a significant attenuation of estradiol-induced MOR internalization, leading to diminished female sexual behavior. These results link membrane-initiated estradiol actions to neural events modulating behavior, demonstrating the physiological importance of ER alpha-to-mGluR1a signaling.
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Affiliation(s)
- Phoebe Dewing
- Department of Neurobiology and Laboratory of Neuroendocrinology of the Brain Research Institute, David Geffen School of Medicine at the University of California, Los Angeles, Los Angeles, California 90095, and
| | - Marissa I. Boulware
- Department of Neuroscience, University of Minnesota, Minneapolis, Minnesota 55455
| | - Kevin Sinchak
- Department of Neurobiology and Laboratory of Neuroendocrinology of the Brain Research Institute, David Geffen School of Medicine at the University of California, Los Angeles, Los Angeles, California 90095, and
| | - Amy Christensen
- Department of Neurobiology and Laboratory of Neuroendocrinology of the Brain Research Institute, David Geffen School of Medicine at the University of California, Los Angeles, Los Angeles, California 90095, and
| | - Paul G. Mermelstein
- Department of Neuroscience, University of Minnesota, Minneapolis, Minnesota 55455
| | - Paul Micevych
- Department of Neurobiology and Laboratory of Neuroendocrinology of the Brain Research Institute, David Geffen School of Medicine at the University of California, Los Angeles, Los Angeles, California 90095, and
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Sergeeva OA, Doreulee N, Chepkova AN, Kazmierczak T, Haas HL. Long-term depression of cortico-striatal synaptic transmission by DHPG depends on endocannabinoid release and nitric oxide synthesis. Eur J Neurosci 2007; 26:1889-94. [PMID: 17868368 DOI: 10.1111/j.1460-9568.2007.05815.x] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
In models of early stage Parkinson's disease (PD), motor deficits are accompanied by excessive activation of striatal glutamate receptors. Metabotropic glutamate group I receptors (mGluR I) play an important but not well-understood role in PD progression. In mouse brain slices, bath application of the mGluR I agonist (RS)-DHPG (3,5-dihydroxyphenylglycine, 100 microm for 20 min) caused a long-term depression of corticostriatal transmission (LTD(DHPG)), which was reversed by three mGluR I antagonists: LY 367385, CPCCOEt and MPEP. LTD(DHPG) required nitric oxide (NO) synthesis as it was blocked by the broad-spectrum NO synthase (NOS) inhibitor Nomega-nitro-l-arginine (NL-Arg) and impaired under blockade of neuronal NOS and in endothelial NOS-deficient mice. Release of endocannabinoids (eCB) was critically involved in this form of striatal plasticity givem that the CB1 receptor antagonist AM251 prevented LTD(DHPG), while the CB1 agonist ACEA elicited LTD. The NO synthesis necessary for LTD(DHPG) induction occurred downstream of CB1 activation as ACEA-evoked LTD was also abolished by NL-Arg. These findings are relevant for the pathophysiology of PD, as they link the overactivation of group I mGluRs and striatal NO production.
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Affiliation(s)
- O A Sergeeva
- Department of Neurophysiology, Heinrich-Heine-University, D-40001, Dusseldorf, Germany.
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Kirschstein T, Bauer M, Müller L, Rüschenschmidt C, Reitze M, Becker AJ, Schoch S, Beck H. Loss of metabotropic glutamate receptor-dependent long-term depression via downregulation of mGluR5 after status epilepticus. J Neurosci 2007; 27:7696-704. [PMID: 17634364 PMCID: PMC6672893 DOI: 10.1523/jneurosci.4572-06.2007] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Synaptic plasticity is thought to be a key mechanism of information storage in the CNS. Different forms of synaptic long-term potentiation have been shown to be impaired in neurological disorders. Here, we show that metabotropic glutamate receptor (mGluR)-dependent long-term depression (LTD), but not NMDA receptor-dependent LTD at Schaffer collateral-CA1 synapses, is profoundly impaired after status epilepticus. Brief application of the group I mGluR agonist (R,S)-3,5-dihydroxyphenylglycine (100 microM; 5 min) induced mGluR LTD in control, but not in pilocarpine-treated rats. Experiments in the presence of selective inhibitors of either mGluR5 [2-methyl-6-(phenylethynyl)-pyridine] or mGluR1 [7-(hydroxyimino)cyclopropachromen-carboxylate ethyl ester and (S)-(+)-alpha-amino-4-carboxy-2-methylbenzeneacetic acid] demonstrate that loss of mGluR LTD is most likely attributable to a loss of mGluR5 function. Quantitative real-time reverse transcription PCR revealed a specific downregulation of mGluR5 mRNA, but not of mGluR1 mRNA in the CA1 region. Furthermore, we detected a strong reduction in mGluR5 protein expression by immunofluorescence and quantitative immunoblotting. Additionally, the scaffolding protein Homer that mediates coupling of mGluR5 to downstream signaling cascades was downregulated. Thus, we conclude that the reduction of mGluR LTD after pilocarpine-induced status epilepticus is the result of the subtype-specific downregulation of mGluR5 and associated downstream signaling components.
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Affiliation(s)
- Timo Kirschstein
- Department of Epileptology, University of Bonn, D-53105 Bonn, Germany.
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Abstract
The activation of metabotropic glutamate receptors (mGluRs) leads to long-term depression (mGluR-LTD) at many synapses of the brain. The induction of mGluR-LTD is well characterized, whereas the mechanisms underlying its expression remain largely elusive. mGluR-LTD in the ventral tegmental area (VTA) efficiently reverses cocaine-induced strengthening of excitatory inputs onto dopamine neurons. We show that mGluR-LTD is expressed by an exchange of GluR2-lacking AMPA receptors for GluR2-containing receptors with a lower single-channel conductance. The synaptic insertion of GluR2 depends on de novo protein synthesis via rapid messenger RNA translation of GluR2. Regulated synthesis of GluR2 in the VTA is therefore required to reverse cocaine-induced synaptic plasticity.
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Affiliation(s)
- Manuel Mameli
- Department of Basic Neuroscience, Medical Faculty, University of Geneva, CH-1211 Geneva, Switzerland
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