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Munari L, Patel V, Johnson N, Mariottini C, Prabha S, Blitzer RD, Iyengar R. Memory discrimination is promoted by the expression of the transcription repressor WT1 in the dentate gyrus. Front Behav Neurosci 2023; 17:1130840. [PMID: 37830039 PMCID: PMC10564998 DOI: 10.3389/fnbeh.2023.1130840] [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] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2022] [Accepted: 08/14/2023] [Indexed: 10/14/2023] Open
Abstract
The hippocampus is critical for the precise formation of contextual memories. Overlapping inputs coming from the entorhinal cortex are processed by the trisynaptic pathway to form distinct memories. Disruption in any step of the circuit flow can lead to a lack of memory precision, and to memory interference. We have identified the transcriptional repressor Wilm's Tumor 1 (WT1) as an important regulator of synaptic plasticity involved in memory discrimination in the hippocampus. In male mice, using viral and transgenic approaches, we showed that WT1 deletion in granule cells of the dentate gyrus (DG) disrupts memory discrimination. With electrophysiological methods, we then identified changes in granule cells' excitability and DG synaptic transmission indicating that WT1 knockdown in DG granule cells disrupts the inhibitory feedforward input from mossy fibers to CA3 by decreasing mIPSCs and shifting the normal excitatory/inhibitory (E/I) balance in the DG → CA3 circuit in favor of excitation. Finally, using a chemogenetic approach, we established a causal link between granule cell hyperexcitability and memory discrimination impairments. Our results suggest that WT1 enables a circuit-level computation that drives pattern discrimination behavior.
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Affiliation(s)
| | | | | | | | | | | | - Ravi Iyengar
- Department of Pharmacological Sciences and Institute for Systems Biomedicine, Icahn School of Medicine at Mount Sinai, New York, NY, United States
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2
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Siddiq MM, Johnson NP, Zorina Y, Yadaw AS, Toro CA, Hansen J, Rabinovich V, Gregorich SM, Xiong Y, Tolentino RE, Hannila SS, Kaplan E, Blitzer RD, Filbin MT, Cardozo CP, Passaglia CL, Iyengar R. A spatially specified systems pharmacology therapy for axonal recovery after injury. Front Pharmacol 2023; 14:1225759. [PMID: 37799971 PMCID: PMC10547904 DOI: 10.3389/fphar.2023.1225759] [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] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2023] [Accepted: 09/06/2023] [Indexed: 10/07/2023] Open
Abstract
There are no known drugs or drug combinations that promote substantial central nervous system axonal regeneration after injury. We used systems pharmacology approaches to model pathways underlying axonal growth and identify a four-drug combination that regulates multiple subcellular processes in the cell body and axons using the optic nerve crush model in rats. We intravitreally injected agonists HU-210 (cannabinoid receptor-1) and IL-6 (interleukin 6 receptor) to stimulate retinal ganglion cells for axonal growth. We applied, in gel foam at the site of nerve injury, Taxol to stabilize growing microtubules, and activated protein C to clear the debris field since computational models predicted that this drug combination regulating two subcellular processes at the growth cone produces synergistic growth. Physiologically, drug treatment restored or preserved pattern electroretinograms and some of the animals had detectable visual evoked potentials in the brain and behavioral optokinetic responses. Morphology experiments show that the four-drug combination protects axons or promotes axonal regrowth to the optic chiasm and beyond. We conclude that spatially targeted drug treatment is therapeutically relevant and can restore limited functional recovery.
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Affiliation(s)
- Mustafa M. Siddiq
- Department of Pharmacological Sciences, Mount Sinai Institute for Systems Biomedicine, Icahn School of Medicine at Mount Sinai, New York, NY, United States
| | - Nicholas P. Johnson
- Department of Pharmacological Sciences, Mount Sinai Institute for Systems Biomedicine, Icahn School of Medicine at Mount Sinai, New York, NY, United States
- Departments of Chemical and Biomedical Engineering, University of South Florida, Tampa, FL, United States
- National Center for the Medical Consequences of Spinal Cord Injury, James J. Peters VA Medical Center, New York, NY, United States
| | - Yana Zorina
- Department of Pharmacological Sciences, Mount Sinai Institute for Systems Biomedicine, Icahn School of Medicine at Mount Sinai, New York, NY, United States
| | - Arjun Singh Yadaw
- Department of Pharmacological Sciences, Mount Sinai Institute for Systems Biomedicine, Icahn School of Medicine at Mount Sinai, New York, NY, United States
| | - Carlos A. Toro
- National Center for the Medical Consequences of Spinal Cord Injury, James J. Peters VA Medical Center, New York, NY, United States
- Department of Medicine, Icahn School of Medicine at Mount Sinai, New York, NY, United States
| | - Jens Hansen
- Department of Pharmacological Sciences, Mount Sinai Institute for Systems Biomedicine, Icahn School of Medicine at Mount Sinai, New York, NY, United States
| | - Vera Rabinovich
- Department of Pharmacological Sciences, Mount Sinai Institute for Systems Biomedicine, Icahn School of Medicine at Mount Sinai, New York, NY, United States
| | - Sarah M. Gregorich
- Departments of Chemical and Biomedical Engineering, University of South Florida, Tampa, FL, United States
| | - Yuguang Xiong
- Department of Pharmacological Sciences, Mount Sinai Institute for Systems Biomedicine, Icahn School of Medicine at Mount Sinai, New York, NY, United States
| | - Rosa E. Tolentino
- Department of Pharmacological Sciences, Mount Sinai Institute for Systems Biomedicine, Icahn School of Medicine at Mount Sinai, New York, NY, United States
| | - Sari S. Hannila
- Department of Human Anatomy and Cell Science, Basic Medical Sciences Building, Winnipeg, NM, United States
| | - Ehud Kaplan
- Department of Pharmacological Sciences, Mount Sinai Institute for Systems Biomedicine, Icahn School of Medicine at Mount Sinai, New York, NY, United States
- Department of Philosophy of Science, Prague and the National Institute of Mental Health, Charles University, Prague, CZ, United States
| | - Robert D. Blitzer
- Department of Pharmacological Sciences, Mount Sinai Institute for Systems Biomedicine, Icahn School of Medicine at Mount Sinai, New York, NY, United States
| | - Marie T. Filbin
- Department of Biological Sciences, Hunter College, City University of New York, New York, NY, United States
| | - Christopher P. Cardozo
- National Center for the Medical Consequences of Spinal Cord Injury, James J. Peters VA Medical Center, New York, NY, United States
- Department of Medicine, Icahn School of Medicine at Mount Sinai, New York, NY, United States
- Department of Rehabilitation Medicine, Icahn School of Medicine at Mount Sinai, New York, NY, United States
| | - Christopher L. Passaglia
- Departments of Chemical and Biomedical Engineering, University of South Florida, Tampa, FL, United States
| | - Ravi Iyengar
- Department of Pharmacological Sciences, Mount Sinai Institute for Systems Biomedicine, Icahn School of Medicine at Mount Sinai, New York, NY, United States
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3
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Godino A, Salery M, Minier-Toribio AM, Patel V, Fullard JF, Parise EM, Martinez-Rivera FJ, Morel C, Roussos P, Blitzer RD, Nestler EJ. Dopaminoceptive D1 and D2 neurons in ventral hippocampus arbitrate approach and avoidance in anxiety. bioRxiv 2023:2023.07.25.550554. [PMID: 37546856 PMCID: PMC10402022 DOI: 10.1101/2023.07.25.550554] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/08/2023]
Abstract
The hippocampus 1-7, as well as dopamine circuits 8-11, coordinate decision-making in anxiety-eliciting situations. Yet, little is known about how dopamine modulates hippocampal representations of emotionally-salient stimuli to inform appropriate resolution of approach versus avoidance conflicts. We here study dopaminoceptive neurons in mouse ventral hippocampus (vHipp), molecularly distinguished by their expression of dopamine D1 or D2 receptors. We show that these neurons are transcriptionally distinct and topographically organized across vHipp subfields and cell types. In the ventral subiculum where they are enriched, both D1 and D2 neurons are recruited during anxiogenic exploration, yet with distinct profiles related to investigation and behavioral selection. In turn, they mediate opposite approach/avoidance responses, and are differentially modulated by dopaminergic transmission in that region. Together, these results suggest that vHipp dopamine dynamics gate exploratory behaviors under contextual uncertainty, implicating dopaminoception in the complex computation engaged in vHipp to govern emotional states.
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Affiliation(s)
- Arthur Godino
- Nash Family Department of Neuroscience & Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | - Marine Salery
- Nash Family Department of Neuroscience & Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | - Angelica M. Minier-Toribio
- Nash Family Department of Neuroscience & Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | - Vishwendra Patel
- Nash Family Department of Neuroscience & Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
- Department of Psychiatry & Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | - John F. Fullard
- Department of Psychiatry & Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
- Department of Genetics and Genomic Sciences & Icahn Genomics Institute, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
- Center for Disease Neurogenomics, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | - Eric M. Parise
- Nash Family Department of Neuroscience & Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | - Freddyson J. Martinez-Rivera
- Nash Family Department of Neuroscience & Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | - Carole Morel
- Nash Family Department of Neuroscience & Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
- Department of Pharmacological Sciences, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | - Panos Roussos
- Department of Psychiatry & Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
- Department of Genetics and Genomic Sciences & Icahn Genomics Institute, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
- Center for Disease Neurogenomics, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
- Mental Illness Research, Education and Clinical Centers, James J. Peters VA Medical Center, Bronx, NY 10468, USA
| | - Robert D. Blitzer
- Department of Psychiatry & Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
- Department of Pharmacological Sciences, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | - Eric J. Nestler
- Nash Family Department of Neuroscience & Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
- Department of Psychiatry & Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
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4
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Fulton SL, Bendl J, Gameiro-Ros I, Fullard JF, Al-Kachak A, Lepack AE, Stewart AF, Singh S, Poller WC, Bastle RM, Hauberg ME, Fakira AK, Chen M, Cuttoli RDD, Cathomas F, Ramakrishnan A, Gleason K, Shen L, Tamminga CA, Milosevic A, Russo SJ, Swirski F, Blitzer RD, Slesinger PA, Roussos P, Maze I. ZBTB7A regulates MDD-specific chromatin signatures and astrocyte-mediated stress vulnerability in orbitofrontal cortex. bioRxiv 2023:2023.05.04.539425. [PMID: 37205394 PMCID: PMC10187272 DOI: 10.1101/2023.05.04.539425] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
Hyperexcitability in the orbitofrontal cortex (OFC) is a key clinical feature of anhedonic domains of Major Depressive Disorder (MDD). However, the cellular and molecular substrates underlying this dysfunction remain unknown. Here, cell-population-specific chromatin accessibility profiling in human OFC unexpectedly mapped genetic risk for MDD exclusively to non-neuronal cells, and transcriptomic analyses revealed significant glial dysregulation in this region. Characterization of MDD-specific cis-regulatory elements identified ZBTB7A - a transcriptional regulator of astrocyte reactivity - as an important mediator of MDD-specific chromatin accessibility and gene expression. Genetic manipulations in mouse OFC demonstrated that astrocytic Zbtb7a is both necessary and sufficient to promote behavioral deficits, cell-type-specific transcriptional and chromatin profiles, and OFC neuronal hyperexcitability induced by chronic stress - a major risk factor for MDD. These data thus highlight a critical role for OFC astrocytes in stress vulnerability and pinpoint ZBTB7A as a key dysregulated factor in MDD that mediates maladaptive astrocytic functions driving OFC hyperexcitability.
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Affiliation(s)
- Sasha L. Fulton
- Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York City, New York, USA
- Nash Family Department of Neuroscience, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Jaroslav Bendl
- Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York City, New York, USA
- Center for Disease Neurogenomics, Icahn School of Medicine at Mount Sinai, New York City, New York, USA
- Icahn Institute for Data Science and Genomic Technology, Icahn School of Medicine at Mount Sinai, New York City, New York, USA
- Department of Psychiatry, Icahn School of Medicine at Mount Sinai, New York City, New York, USA
- Department of Genetics and Genomic Science, Icahn School of Medicine at Mount Sinai, New York City, New York, USA
| | - Isabel Gameiro-Ros
- Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York City, New York, USA
- Nash Family Department of Neuroscience, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - John F. Fullard
- Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York City, New York, USA
- Center for Disease Neurogenomics, Icahn School of Medicine at Mount Sinai, New York City, New York, USA
- Icahn Institute for Data Science and Genomic Technology, Icahn School of Medicine at Mount Sinai, New York City, New York, USA
- Department of Psychiatry, Icahn School of Medicine at Mount Sinai, New York City, New York, USA
- Department of Genetics and Genomic Science, Icahn School of Medicine at Mount Sinai, New York City, New York, USA
| | - Amni Al-Kachak
- Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York City, New York, USA
- Nash Family Department of Neuroscience, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Ashley E. Lepack
- Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York City, New York, USA
- Nash Family Department of Neuroscience, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Andrew F. Stewart
- Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York City, New York, USA
- Nash Family Department of Neuroscience, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Sumnima Singh
- Department of Cardiology, Icahn School of Medicine at Mount Sinai, New York City, New York, USA
- Department of Diagnostic, Molecular and Interventional Radiology, Icahn School of Medicine at Mount Sinai, New York City, New York, USA
- The Cardiovascular Research Institute, Icahn School of Medicine at Mount Sinai, New York City, New York, USA
| | - Wolfram C. Poller
- Department of Cardiology, Icahn School of Medicine at Mount Sinai, New York City, New York, USA
- Department of Diagnostic, Molecular and Interventional Radiology, Icahn School of Medicine at Mount Sinai, New York City, New York, USA
- The Cardiovascular Research Institute, Icahn School of Medicine at Mount Sinai, New York City, New York, USA
| | - Ryan M. Bastle
- Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York City, New York, USA
- Nash Family Department of Neuroscience, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Mads E. Hauberg
- Center for Disease Neurogenomics, Icahn School of Medicine at Mount Sinai, New York City, New York, USA
- Icahn Institute for Data Science and Genomic Technology, Icahn School of Medicine at Mount Sinai, New York City, New York, USA
- Department of Psychiatry, Icahn School of Medicine at Mount Sinai, New York City, New York, USA
| | - Amanda K. Fakira
- Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York City, New York, USA
- Nash Family Department of Neuroscience, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Min Chen
- Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York City, New York, USA
- Nash Family Department of Neuroscience, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Romain Durand-de Cuttoli
- Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York City, New York, USA
- Nash Family Department of Neuroscience, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Flurin Cathomas
- Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York City, New York, USA
- Nash Family Department of Neuroscience, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Aarthi Ramakrishnan
- Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York City, New York, USA
- Nash Family Department of Neuroscience, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Kelly Gleason
- Department of Psychiatry, UT Southwestern Medical Center, Dallas, TX, USA
| | - Li Shen
- Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York City, New York, USA
- Nash Family Department of Neuroscience, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Carol A. Tamminga
- Department of Psychiatry, UT Southwestern Medical Center, Dallas, TX, USA
| | - Ana Milosevic
- Laboratory of Molecular and Cellular Neuroscience, Rockefeller University, New York, New York, USA
| | - Scott J. Russo
- Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York City, New York, USA
- Nash Family Department of Neuroscience, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Filip Swirski
- Department of Cardiology, Icahn School of Medicine at Mount Sinai, New York City, New York, USA
- Department of Diagnostic, Molecular and Interventional Radiology, Icahn School of Medicine at Mount Sinai, New York City, New York, USA
- The Cardiovascular Research Institute, Icahn School of Medicine at Mount Sinai, New York City, New York, USA
| | - Robert D. Blitzer
- Department of Pharmacological Sciences, Icahn School of Medicine at Mount Sinai, New York City, New York, USA
| | - Paul A. Slesinger
- Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York City, New York, USA
- Nash Family Department of Neuroscience, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Panos Roussos
- Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York City, New York, USA
- Center for Disease Neurogenomics, Icahn School of Medicine at Mount Sinai, New York City, New York, USA
- Icahn Institute for Data Science and Genomic Technology, Icahn School of Medicine at Mount Sinai, New York City, New York, USA
- Department of Psychiatry, Icahn School of Medicine at Mount Sinai, New York City, New York, USA
- Department of Genetics and Genomic Science, Icahn School of Medicine at Mount Sinai, New York City, New York, USA
- Center for Dementia Research, Nathan Kline Institute for Psychiatric Research, Orangeburg, New York, USA
- Mental Illness Research Education and Clinical Center (MIRECC), James J. Peters VA Medical Center, Bronx, New York, USA
| | - Ian Maze
- Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York City, New York, USA
- Nash Family Department of Neuroscience, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- Department of Pharmacological Sciences, Icahn School of Medicine at Mount Sinai, New York City, New York, USA
- Howard Hughes Medical Institute, Icahn School of Medicine at Mount Sinai, New York, NY, USA
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5
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Fulton SL, Wenderski W, Lepack AE, Eagle AL, Fanutza T, Bastle RM, Ramakrishnan A, Hays EC, Neal A, Bendl J, Farrelly LA, Al-Kachak A, Lyu Y, Cetin B, Chan JC, Tran TN, Neve RL, Roper RJ, Brennand KJ, Roussos P, Schimenti JC, Friedman AK, Shen L, Blitzer RD, Robison AJ, Crabtree GR, Maze I. Rescue of deficits by Brwd1 copy number restoration in the Ts65Dn mouse model of Down syndrome. Nat Commun 2022; 13:6384. [PMID: 36289231 PMCID: PMC9606253 DOI: 10.1038/s41467-022-34200-0] [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] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2020] [Accepted: 10/17/2022] [Indexed: 12/25/2022] Open
Abstract
With an incidence of ~1 in 800 births, Down syndrome (DS) is the most common chromosomal condition linked to intellectual disability worldwide. While the genetic basis of DS has been identified as a triplication of chromosome 21 (HSA21), the genes encoded from HSA21 that directly contribute to cognitive deficits remain incompletely understood. Here, we found that the HSA21-encoded chromatin effector, BRWD1, was upregulated in neurons derived from iPS cells from an individual with Down syndrome and brain of trisomic mice. We showed that selective copy number restoration of Brwd1 in trisomic animals rescued deficits in hippocampal LTP, cognition and gene expression. We demonstrated that Brwd1 tightly binds the BAF chromatin remodeling complex, and that increased Brwd1 expression promotes BAF genomic mistargeting. Importantly, Brwd1 renormalization rescued aberrant BAF localization, along with associated changes in chromatin accessibility and gene expression. These findings establish BRWD1 as a key epigenomic mediator of normal neurodevelopment and an important contributor to DS-related phenotypes.
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Affiliation(s)
- Sasha L. Fulton
- grid.59734.3c0000 0001 0670 2351Nash Family Department of Neuroscience, Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York, NY 10029 USA
| | - Wendy Wenderski
- grid.168010.e0000000419368956Department of Pathology, Stanford Medical School, Palo Alto, CA 94305 USA ,grid.168010.e0000000419368956Department of Genetics, Stanford Medical School, Palo Alto, CA 94305 USA ,grid.168010.e0000000419368956Department of Developmental Biology, Stanford Medical School, Palo Alto, CA 94305 USA ,grid.168010.e0000000419368956Howard Hughes Medical Institute, Stanford University, Palo Alto, CA 94305 USA
| | - Ashley E. Lepack
- grid.59734.3c0000 0001 0670 2351Nash Family Department of Neuroscience, Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York, NY 10029 USA
| | - Andrew L. Eagle
- grid.17088.360000 0001 2150 1785Department of Physiology, Michigan State University, East Lansing, MI 48824 USA
| | - Tomas Fanutza
- grid.59734.3c0000 0001 0670 2351Department of Pharmacological Sciences, Icahn School of Medicine at Mount Sinai, New York, NY 10029 USA
| | - Ryan M. Bastle
- grid.59734.3c0000 0001 0670 2351Nash Family Department of Neuroscience, Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York, NY 10029 USA
| | - Aarthi Ramakrishnan
- grid.59734.3c0000 0001 0670 2351Nash Family Department of Neuroscience, Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York, NY 10029 USA
| | - Emma C. Hays
- grid.59734.3c0000 0001 0670 2351Nash Family Department of Neuroscience, Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York, NY 10029 USA
| | - Arianna Neal
- grid.59734.3c0000 0001 0670 2351Nash Family Department of Neuroscience, Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York, NY 10029 USA
| | - Jaroslav Bendl
- grid.59734.3c0000 0001 0670 2351Department of Psychiatry, Icahn School of Medicine at Mount Sinai, New York, NY 10029 USA ,grid.59734.3c0000 0001 0670 2351Department of Genetics and Genomics, Icahn School of Medicine at Mount Sinai, New York, NY 10029 USA ,grid.59734.3c0000 0001 0670 2351Center for Disease Neuroepigenomics, Icahn School of Medicine at Mount Sinai, New York, NY 10029 USA
| | - Lorna A. Farrelly
- grid.59734.3c0000 0001 0670 2351Nash Family Department of Neuroscience, Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York, NY 10029 USA
| | - Amni Al-Kachak
- grid.59734.3c0000 0001 0670 2351Nash Family Department of Neuroscience, Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York, NY 10029 USA
| | - Yang Lyu
- grid.59734.3c0000 0001 0670 2351Nash Family Department of Neuroscience, Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York, NY 10029 USA
| | - Bulent Cetin
- grid.59734.3c0000 0001 0670 2351Nash Family Department of Neuroscience, Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York, NY 10029 USA
| | - Jennifer C. Chan
- grid.59734.3c0000 0001 0670 2351Nash Family Department of Neuroscience, Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York, NY 10029 USA
| | - Tina N. Tran
- grid.5386.8000000041936877XDepartment of Biomedical Sciences, Cornell University, Ithaca, NY 14853 USA ,grid.5386.8000000041936877XDepartment of Molecular Biology and Genetics, Cornell University, Ithaca, NY 14853 USA
| | - Rachael L. Neve
- grid.116068.80000 0001 2341 2786McGovern Institute for Brain Research, Massachusetts Institute of Technology, Cambridge, MA 02139 USA
| | - Randall J. Roper
- grid.257413.60000 0001 2287 3919Department of Biology, Indiana University-Purdue University, Indianapolis, IN 46202 USA
| | - Kristen J. Brennand
- grid.59734.3c0000 0001 0670 2351Nash Family Department of Neuroscience, Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York, NY 10029 USA ,grid.59734.3c0000 0001 0670 2351Department of Psychiatry, Icahn School of Medicine at Mount Sinai, New York, NY 10029 USA ,grid.59734.3c0000 0001 0670 2351Department of Genetics and Genomics, Icahn School of Medicine at Mount Sinai, New York, NY 10029 USA ,grid.59734.3c0000 0001 0670 2351Black Family Stem Cell Institute, Icahn School of Medicine at Mount Sinai, New York, NY 10029 USA ,grid.47100.320000000419368710Present Address: Departments of Psychiatry and Genetics, Wu Tsai Institute, Yale School of Medicine, New Haven, CT 065109 USA
| | - Panos Roussos
- grid.59734.3c0000 0001 0670 2351Department of Psychiatry, Icahn School of Medicine at Mount Sinai, New York, NY 10029 USA ,grid.59734.3c0000 0001 0670 2351Department of Genetics and Genomics, Icahn School of Medicine at Mount Sinai, New York, NY 10029 USA ,grid.59734.3c0000 0001 0670 2351Center for Disease Neuroepigenomics, Icahn School of Medicine at Mount Sinai, New York, NY 10029 USA ,J.J. Peters Veterans Affairs Hospital, Bronx, NY 10468 USA
| | - John C. Schimenti
- grid.5386.8000000041936877XDepartment of Biomedical Sciences, Cornell University, Ithaca, NY 14853 USA ,grid.5386.8000000041936877XDepartment of Molecular Biology and Genetics, Cornell University, Ithaca, NY 14853 USA
| | - Allyson K. Friedman
- grid.257167.00000 0001 2183 6649Department of Biological Sciences, City University of New York-Hunter College, New York, NY 10065 USA
| | - Li Shen
- grid.59734.3c0000 0001 0670 2351Nash Family Department of Neuroscience, Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York, NY 10029 USA
| | - Robert D. Blitzer
- grid.59734.3c0000 0001 0670 2351Department of Pharmacological Sciences, Icahn School of Medicine at Mount Sinai, New York, NY 10029 USA ,grid.59734.3c0000 0001 0670 2351Department of Psychiatry, Icahn School of Medicine at Mount Sinai, New York, NY 10029 USA
| | - Alfred J. Robison
- grid.17088.360000 0001 2150 1785Department of Physiology, Michigan State University, East Lansing, MI 48824 USA
| | - Gerald R. Crabtree
- grid.168010.e0000000419368956Department of Pathology, Stanford Medical School, Palo Alto, CA 94305 USA ,grid.168010.e0000000419368956Department of Genetics, Stanford Medical School, Palo Alto, CA 94305 USA ,grid.168010.e0000000419368956Department of Developmental Biology, Stanford Medical School, Palo Alto, CA 94305 USA ,grid.168010.e0000000419368956Howard Hughes Medical Institute, Stanford University, Palo Alto, CA 94305 USA
| | - Ian Maze
- grid.59734.3c0000 0001 0670 2351Nash Family Department of Neuroscience, Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York, NY 10029 USA ,grid.59734.3c0000 0001 0670 2351Howard Hughes Medical Institute, Icahn School of Medicine at Mount Sinai, New York, NY 10029 USA
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6
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Takahashi A, Durand-de Cuttoli R, Flanigan ME, Hasegawa E, Tsunematsu T, Aleyasin H, Cherasse Y, Miya K, Okada T, Keino-Masu K, Mitsui K, Li L, Patel V, Blitzer RD, Lazarus M, Tanaka KF, Yamanaka A, Sakurai T, Ogawa S, Russo SJ. Lateral habenula glutamatergic neurons projecting to the dorsal raphe nucleus promote aggressive arousal in mice. Nat Commun 2022; 13:4039. [PMID: 35864121 PMCID: PMC9304121 DOI: 10.1038/s41467-022-31728-z] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [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: 05/14/2021] [Accepted: 06/29/2022] [Indexed: 02/04/2023] Open
Abstract
The dorsal raphe nucleus (DRN) is known to control aggressive behavior in mice. Here, we found that glutamatergic projections from the lateral habenula (LHb) to the DRN were activated in male mice that experienced pre-exposure to a rival male mouse ("social instigation") resulting in heightened intermale aggression. Both chemogenetic and optogenetic suppression of the LHb-DRN projection blocked heightened aggression after social instigation in male mice. In contrast, inhibition of this pathway did not affect basal levels of aggressive behavior, suggesting that the activity of the LHb-DRN projection is not necessary for the expression of species-typical aggressive behavior, but required for the increase of aggressive behavior resulting from social instigation. Anatomical analysis showed that LHb neurons synapse on non-serotonergic DRN neurons that project to the ventral tegmental area (VTA), and optogenetic activation of the DRN-VTA projection increased aggressive behaviors. Our results demonstrate that the LHb glutamatergic inputs to the DRN promote aggressive arousal induced by social instigation, which contributes to aggressive behavior by activating VTA-projecting non-serotonergic DRN neurons as one of its potential targets.
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Affiliation(s)
- Aki Takahashi
- Laboratory of Behavioral Neurobiology, Faculty of Human Sciences, University of Tsukuba, Tsukuba, Ibaraki, 305-8577, Japan.
- Laboratory of Behavioral Neuroendocrinology, Faculty of Human Sciences, University of Tsukuba, Tsukuba, Ibaraki, 305-8577, Japan.
- Nash Family Department of Neuroscience and Brain & Body Research Center, Icahn School of Medicine at Mount Sinai, New York, NY, 10029, USA.
| | - Romain Durand-de Cuttoli
- Nash Family Department of Neuroscience and Brain & Body Research Center, Icahn School of Medicine at Mount Sinai, New York, NY, 10029, USA
| | - Meghan E Flanigan
- Nash Family Department of Neuroscience and Brain & Body Research Center, Icahn School of Medicine at Mount Sinai, New York, NY, 10029, USA
- Bowles Center for Alcohol Studies, University of North Carolina School of Medicine, Chapel Hill, 27599, NC, USA
| | - Emi Hasegawa
- Department of Molecular Behavioral Physiology, Faculty of Medicine, University of Tsukuba, Tsukuba, Ibaraki, 305-8575, Japan
- International Institute for Integrative Sleep Medicine (WPI-IIIS), University of Tsukuba, Tsukuba, Ibaraki, 305-8575, Japan
| | - Tomomi Tsunematsu
- Super-network Brain Physiology, Graduate School of Life Sciences, Tohoku University, Sendai, Miyagi, 980-8577, Japan
- Advanced Interdisciplinary Research Division, Frontier Research Institute for Interdisciplinary Sciences, Tohoku University, Sendai, Miyagi, 980-8578, Japan
- Precursory Research for Embryonic Science and Technology, Japan Science and Technology Agency, Kawaguchi, Saitama, 332-0012, Japan
| | - Hossein Aleyasin
- Nash Family Department of Neuroscience and Brain & Body Research Center, Icahn School of Medicine at Mount Sinai, New York, NY, 10029, USA
| | - Yoan Cherasse
- International Institute for Integrative Sleep Medicine (WPI-IIIS), University of Tsukuba, Tsukuba, Ibaraki, 305-8575, Japan
| | - Ken Miya
- Department of Molecular Neurobiology, Faculty of Medicine, University of Tsukuba, Tsukuba, Ibaraki, 305-8575, Japan
- Graduate School of Comprehensive Human Sciences, University of Tsukuba, Tsukuba, Ibaraki, 305-8575, Japan
| | - Takuya Okada
- Department of Molecular Neurobiology, Faculty of Medicine, University of Tsukuba, Tsukuba, Ibaraki, 305-8575, Japan
| | - Kazuko Keino-Masu
- Department of Molecular Neurobiology, Faculty of Medicine, University of Tsukuba, Tsukuba, Ibaraki, 305-8575, Japan
| | - Koshiro Mitsui
- Laboratory of Behavioral Neurobiology, Faculty of Human Sciences, University of Tsukuba, Tsukuba, Ibaraki, 305-8577, Japan
- Graduate School of Comprehensive Human Sciences, University of Tsukuba, Tsukuba, Ibaraki, 305-8575, Japan
| | - Long Li
- Nash Family Department of Neuroscience and Brain & Body Research Center, Icahn School of Medicine at Mount Sinai, New York, NY, 10029, USA
| | - Vishwendra Patel
- Department of Pharmacological Sciences and Department of Psychiatry, Icahn School of Medicine at Mount Sinai, New York, NY, 10029, USA
| | - Robert D Blitzer
- Department of Pharmacological Sciences and Department of Psychiatry, Icahn School of Medicine at Mount Sinai, New York, NY, 10029, USA
| | - Michael Lazarus
- International Institute for Integrative Sleep Medicine (WPI-IIIS), University of Tsukuba, Tsukuba, Ibaraki, 305-8575, Japan
| | - Kenji F Tanaka
- Department of Neuropsychiatry, Keio University School of Medicine, Shinjuku, Tokyo, 160-8582, Japan
| | - Akihiro Yamanaka
- Department of Neuroscience II, Research Institute of Environmental Medicine, Nagoya University, Nagoya, Aichi, 464-8601, Japan
| | - Takeshi Sakurai
- Department of Molecular Behavioral Physiology, Faculty of Medicine, University of Tsukuba, Tsukuba, Ibaraki, 305-8575, Japan
- International Institute for Integrative Sleep Medicine (WPI-IIIS), University of Tsukuba, Tsukuba, Ibaraki, 305-8575, Japan
| | - Sonoko Ogawa
- Laboratory of Behavioral Neuroendocrinology, Faculty of Human Sciences, University of Tsukuba, Tsukuba, Ibaraki, 305-8577, Japan
| | - Scott J Russo
- Nash Family Department of Neuroscience and Brain & Body Research Center, Icahn School of Medicine at Mount Sinai, New York, NY, 10029, USA
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7
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Readhead B, Haure-Mirande JV, Mastroeni D, Audrain M, Fanutza T, Kim SH, Blitzer RD, Gandy S, Dudley JT, Ehrlich ME. miR155 regulation of behavior, neuropathology, and cortical transcriptomics in Alzheimer's disease. Acta Neuropathol 2020; 140:295-315. [PMID: 32666270 PMCID: PMC8414561 DOI: 10.1007/s00401-020-02185-z] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2020] [Accepted: 06/24/2020] [Indexed: 12/19/2022]
Abstract
MicroRNAs are recognized as important regulators of many facets of physiological brain function while also being implicated in the pathogenesis of several neurological disorders. Dysregulation of miR155 is widely reported across a variety of neurodegenerative conditions, including Alzheimer's disease (AD), Parkinson's disease, amyotrophic lateral sclerosis, and traumatic brain injury. In previous work, we observed that experimentally validated miR155 gene targets were consistently enriched among genes identified as differentially expressed across multiple brain tissue and disease contexts. In particular, we found that human herpesvirus-6A (HHV-6A) suppressed miR155, recapitulating reports of miR155 inhibition by HHV-6A in infected T-cells, thyrocytes, and natural killer cells. In earlier studies, we also reported the effects of constitutive deletion of miR155 on accelerating the accumulation of Aβ deposits in 4-month-old APP/PSEN1 mice. Herein, we complete the cumulative characterization of transcriptomic, electrophysiological, neuropathological, and learning behavior profiles from 4-, 8- and 10-month-old WT and APP/PSEN1 mice in the absence or presence of miR155. We also integrated human post-mortem brain RNA-sequences from four independent AD consortium studies, together comprising 928 samples collected from six brain regions. We report that gene expression perturbations associated with miR155 deletion in mouse cortex are in aggregate observed to be concordant with AD-associated changes across these independent human late-onset AD (LOAD) data sets, supporting the relevance of our findings to human disease. LOAD has recently been formulated as the clinicopathological manifestation of a multiplex of genetic underpinnings and pathophysiological mechanisms. Our accumulated data are consistent with such a formulation, indicating that miR155 may be uniquely positioned at the intersection of at least four components of this LOAD "multiplex": (1) innate immune response pathways; (2) viral response gene networks; (3) synaptic pathology; and (4) proamyloidogenic pathways involving the amyloid β peptide (Aβ).
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Affiliation(s)
- Ben Readhead
- Arizona State University-Banner Neurodegenerative Disease Research Center, Arizona State University, Tempe, AZ, 85281, USA
- Icahn Institute of Genomic Sciences and Multiscale Biology, Icahn School of Medicine at Mount Sinai, New York, NY, 10029, USA
| | | | - Diego Mastroeni
- Arizona State University-Banner Neurodegenerative Disease Research Center, Arizona State University, Tempe, AZ, 85281, USA
| | - Mickael Audrain
- Department of Neurology, Icahn School of Medicine at Mount Sinai, New York, NY, 10029, USA
| | - Tomas Fanutza
- Department of Neurology, Icahn School of Medicine at Mount Sinai, New York, NY, 10029, USA
| | - Soong H Kim
- Department of Neurology, Icahn School of Medicine at Mount Sinai, New York, NY, 10029, USA
| | - Robert D Blitzer
- Department of Pharmacological Sciences, Icahn School of Medicine at Mount Sinai, New York, NY, 10029, USA
- Department of Psychiatry, Icahn School of Medicine at Mount Sinai, New York, NY, 10029, USA
| | - Sam Gandy
- Department of Neurology, Icahn School of Medicine at Mount Sinai, New York, NY, 10029, USA
- Alzheimer's Disease Research Center, Department of Psychiatry, Icahn School of Medicine at Mount Sinai, New York, NY, 10029, USA
- Mount Sinai Center for Cognitive Health and NFL Neurological Care, Department of Neurology, New York, NY, 10029, USA
- James J. Peters VA Medical Center, 130 West Kingsbridge Road, New York, NY, 10468, USA
| | - Joel T Dudley
- Icahn Institute of Genomic Sciences and Multiscale Biology, Icahn School of Medicine at Mount Sinai, New York, NY, 10029, USA.
| | - Michelle E Ehrlich
- Icahn Institute of Genomic Sciences and Multiscale Biology, Icahn School of Medicine at Mount Sinai, New York, NY, 10029, USA.
- Department of Neurology, Icahn School of Medicine at Mount Sinai, New York, NY, 10029, USA.
- Department of Pediatrics, Icahn School of Medicine at Mount Sinai, New York, NY, 10029, USA.
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8
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Lachance V, Wang Q, Sweet E, Choi I, Cai CZ, Zhuang XX, Zhang Y, Jiang JL, Blitzer RD, Bozdagi-Gunal O, Zhang B, Lu JH, Yue Z. Autophagy protein NRBF2 has reduced expression in Alzheimer's brains and modulates memory and amyloid-beta homeostasis in mice. Mol Neurodegener 2019; 14:43. [PMID: 31775806 PMCID: PMC6882183 DOI: 10.1186/s13024-019-0342-4] [Citation(s) in RCA: 41] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2019] [Accepted: 10/31/2019] [Indexed: 12/24/2022] Open
Abstract
BACKGROUND Dysfunctional autophagy is implicated in Alzheimer's Disease (AD) pathogenesis. The alterations in the expression of many autophagy related genes (ATGs) have been reported in AD brains; however, the disparity of the changes confounds the role of autophagy in AD. METHODS To further understand the autophagy alteration in AD brains, we analyzed transcriptomic (RNAseq) datasets of several brain regions (BA10, BA22, BA36 and BA44 in 223 patients compared to 59 healthy controls) and measured the expression of 130 ATGs. We used autophagy-deficient mouse models to assess the impact of the identified ATGs depletion on memory, autophagic activity and amyloid-β (Aβ) production. RESULTS We observed significant downregulation of multiple components of two autophagy kinase complexes BECN1-PIK3C3 and ULK1/2-FIP200 specifically in the parahippocampal gyrus (BA36). Most importantly, we demonstrated that deletion of NRBF2, a component of the BECN1-PIK3C3 complex, which also associates with ULK1/2-FIP200 complex, impairs memory in mice, alters long-term potentiation (LTP), reduces autophagy in mouse hippocampus, and promotes Aβ accumulation. Furthermore, AAV-mediated NRBF2 overexpression in the hippocampus not only rescues the impaired autophagy and memory deficits in NRBF2-depleted mice, but also reduces β-amyloid levels and improves memory in an AD mouse model. CONCLUSIONS Our data not only implicates NRBF2 deficiency as a risk factor for cognitive impairment associated with AD, but also support the idea of NRBF2 as a potential therapeutic target for AD.
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Affiliation(s)
- Véronik Lachance
- Department of Neurology, The Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York, NY, 10029, USA
| | - Qian Wang
- Department of Neurology, The Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York, NY, 10029, USA.,Department of Genetics and Genomic Sciences, Icahn School of Medicine at Mount Sinai, New York, NY, 10029, USA
| | - Eric Sweet
- Department of Neurology, The Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York, NY, 10029, USA.,Departments of Psychiatry and Pharmacological Sciences, Icahn School of Medicine at Mount Sinai, New York, NY, 10029, USA.,Present Address: Department of Biology, West Chester University, West Chester, PA, 19383, USA
| | - Insup Choi
- Department of Neurology, The Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York, NY, 10029, USA
| | - Cui-Zan Cai
- State Key Laboratory of Quality Research in Chinese Medicine, Institute of Chinese Medical Sciences, University of Macau, Taipa, Macau SAR, China
| | - Xu-Xu Zhuang
- State Key Laboratory of Quality Research in Chinese Medicine, Institute of Chinese Medical Sciences, University of Macau, Taipa, Macau SAR, China
| | - Yuanxi Zhang
- Department of Neurology, The Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York, NY, 10029, USA
| | - Jessica Li Jiang
- Department of Neurology, The Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York, NY, 10029, USA
| | - Robert D Blitzer
- Departments of Psychiatry and Pharmacological Sciences, Icahn School of Medicine at Mount Sinai, New York, NY, 10029, USA
| | - Ozlem Bozdagi-Gunal
- Department of Neuroscience, Icahn School of Medicine at Mount Sinai, New York, NY, 10029, USA.,Present Address: Department of Psychiatry, Rutgers New Jersey Medical School, Newark, NJ, 07103, USA
| | - Bin Zhang
- Department of Genetics and Genomic Sciences, Icahn School of Medicine at Mount Sinai, New York, NY, 10029, USA
| | - Jia-Hong Lu
- State Key Laboratory of Quality Research in Chinese Medicine, Institute of Chinese Medical Sciences, University of Macau, Taipa, Macau SAR, China.
| | - Zhenyu Yue
- Department of Neurology, The Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York, NY, 10029, USA.
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9
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Mariottini C, Munari L, Gunzel E, Seco JM, Tzavaras N, Hansen J, Stern SA, Gao V, Aleyasin H, Sharma A, Azeloglu EU, Hodes GE, Russo SJ, Huff V, Birtwistle MR, Blitzer RD, Alberini CM, Iyengar R. Wilm's tumor 1 promotes memory flexibility. Nat Commun 2019; 10:3756. [PMID: 31434897 PMCID: PMC6704057 DOI: 10.1038/s41467-019-11781-x] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2018] [Accepted: 07/31/2019] [Indexed: 02/06/2023] Open
Abstract
Under physiological conditions, strength and persistence of memory must be regulated in order to produce behavioral flexibility. In fact, impairments in memory flexibility are associated with pathologies such as post-traumatic stress disorder or autism; however, the underlying mechanisms that enable memory flexibility are still poorly understood. Here, we identify transcriptional repressor Wilm's Tumor 1 (WT1) as a critical synaptic plasticity regulator that decreases memory strength, promoting memory flexibility. WT1 is activated in the hippocampus following induction of long-term potentiation (LTP) or learning. WT1 knockdown enhances CA1 neuronal excitability, LTP and long-term memory whereas its overexpression weakens memory retention. Moreover, forebrain WT1-deficient mice show deficits in both reversal, sequential learning tasks and contextual fear extinction, exhibiting impaired memory flexibility. We conclude that WT1 limits memory strength or promotes memory weakening, thus enabling memory flexibility, a process that is critical for learning from new experiences.
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Affiliation(s)
- Chiara Mariottini
- Department of Pharmacological Sciences, Icahn School of Medicine at Mount Sinai, One Gustave Levy Place, New York, 10029, NY, USA.
- Systems Biology Center, Icahn School of Medicine at Mount Sinai, One Gustave Levy Place, New York, 10029, NY, USA.
| | - Leonardo Munari
- Department of Pharmacological Sciences, Icahn School of Medicine at Mount Sinai, One Gustave Levy Place, New York, 10029, NY, USA
| | - Ellen Gunzel
- Department of Pharmacological Sciences, Icahn School of Medicine at Mount Sinai, One Gustave Levy Place, New York, 10029, NY, USA
- Systems Biology Center, Icahn School of Medicine at Mount Sinai, One Gustave Levy Place, New York, 10029, NY, USA
| | - Joseph M Seco
- Department of Pharmacological Sciences, Icahn School of Medicine at Mount Sinai, One Gustave Levy Place, New York, 10029, NY, USA
| | - Nikos Tzavaras
- Department of Pharmacological Sciences, Icahn School of Medicine at Mount Sinai, One Gustave Levy Place, New York, 10029, NY, USA
| | - Jens Hansen
- Department of Pharmacological Sciences, Icahn School of Medicine at Mount Sinai, One Gustave Levy Place, New York, 10029, NY, USA
- Systems Biology Center, Icahn School of Medicine at Mount Sinai, One Gustave Levy Place, New York, 10029, NY, USA
| | - Sarah A Stern
- Department of Neuroscience, Icahn School of Medicine at Mount Sinai, One Gustave Levy Place, New York, 10029, NY, USA
- Center for Neural Science, New York University, New York, 10003, NY, USA
| | - Virginia Gao
- Department of Neuroscience, Icahn School of Medicine at Mount Sinai, One Gustave Levy Place, New York, 10029, NY, USA
- Center for Neural Science, New York University, New York, 10003, NY, USA
| | - Hossein Aleyasin
- Department of Neuroscience, Icahn School of Medicine at Mount Sinai, One Gustave Levy Place, New York, 10029, NY, USA
| | - Ali Sharma
- Department of Pharmacological Sciences, Icahn School of Medicine at Mount Sinai, One Gustave Levy Place, New York, 10029, NY, USA
| | - Evren U Azeloglu
- Department of Medicine, Division of Nephrology, Icahn School of Medicine at Mount Sinai, One Gustave Levy Place, New York, 10029, NY, USA
| | - Georgia E Hodes
- Department of Neuroscience, Icahn School of Medicine at Mount Sinai, One Gustave Levy Place, New York, 10029, NY, USA
| | - Scott J Russo
- Department of Neuroscience, Icahn School of Medicine at Mount Sinai, One Gustave Levy Place, New York, 10029, NY, USA
| | - Vicki Huff
- Department of Genetics, M.D. Anderson Cancer Center, University of Texas, Houston, 77030, TX, USA
| | - Marc R Birtwistle
- Department of Pharmacological Sciences, Icahn School of Medicine at Mount Sinai, One Gustave Levy Place, New York, 10029, NY, USA
- Systems Biology Center, Icahn School of Medicine at Mount Sinai, One Gustave Levy Place, New York, 10029, NY, USA
| | - Robert D Blitzer
- Department of Pharmacological Sciences, Icahn School of Medicine at Mount Sinai, One Gustave Levy Place, New York, 10029, NY, USA
| | - Cristina M Alberini
- Department of Neuroscience, Icahn School of Medicine at Mount Sinai, One Gustave Levy Place, New York, 10029, NY, USA.
- Center for Neural Science, New York University, New York, 10003, NY, USA.
| | - Ravi Iyengar
- Department of Pharmacological Sciences, Icahn School of Medicine at Mount Sinai, One Gustave Levy Place, New York, 10029, NY, USA.
- Systems Biology Center, Icahn School of Medicine at Mount Sinai, One Gustave Levy Place, New York, 10029, NY, USA.
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10
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Haure-Mirande JV, Wang M, Audrain M, Fanutza T, Kim SH, Heja S, Readhead B, Dudley JT, Blitzer RD, Schadt EE, Zhang B, Gandy S, Ehrlich ME. Correction: Integrative approach to sporadic Alzheimer's disease: deficiency of TYROBP in cerebral Aβ amyloidosis mouse normalizes clinical phenotype and complement subnetwork molecular pathology without reducing Aβ burden. Mol Psychiatry 2019; 24:472. [PMID: 30464330 PMCID: PMC7608234 DOI: 10.1038/s41380-018-0301-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
This article was originally published under standard licence, but has now been made available under a CC BY 4.0 license. The PDF and HTML versions of the paper have been modified accordingly.
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Affiliation(s)
- Jean-Vianney Haure-Mirande
- 0000 0001 0670 2351grid.59734.3cDepartment of Neurology, Icahn School of Medicine at Mount Sinai, New York, NY 10029 USA
| | - Minghui Wang
- 0000 0001 0670 2351grid.59734.3cDepartment of Genetics and Genomic Sciences and Icahn Institute of Genomic Sciences, Icahn School of Medicine at Mount Sinai, New York, NY 10029 USA
| | - Mickael Audrain
- 0000 0001 0670 2351grid.59734.3cDepartment of Neurology, Icahn School of Medicine at Mount Sinai, New York, NY 10029 USA
| | - Tomas Fanutza
- 0000 0001 0670 2351grid.59734.3cDepartment of Neurology, Icahn School of Medicine at Mount Sinai, New York, NY 10029 USA
| | - Soong Ho Kim
- 0000 0001 0670 2351grid.59734.3cDepartment of Neurology, Icahn School of Medicine at Mount Sinai, New York, NY 10029 USA
| | - Szilvia Heja
- 0000 0001 0670 2351grid.59734.3cDepartment of Neurology, Icahn School of Medicine at Mount Sinai, New York, NY 10029 USA
| | - Ben Readhead
- 0000 0001 0670 2351grid.59734.3cDepartment of Genetics and Genomic Sciences and Icahn Institute of Genomic Sciences, Icahn School of Medicine at Mount Sinai, New York, NY 10029 USA
| | - Joel T. Dudley
- 0000 0001 0670 2351grid.59734.3cDepartment of Genetics and Genomic Sciences and Icahn Institute of Genomic Sciences, Icahn School of Medicine at Mount Sinai, New York, NY 10029 USA
| | - Robert D. Blitzer
- 0000 0001 0670 2351grid.59734.3cDepartments of Pharmacological Sciences and Psychiatry, Icahn School of Medicine at Mount Sinai, New York, NY 10029 USA
| | - Eric E. Schadt
- 0000 0001 0670 2351grid.59734.3cDepartment of Genetics and Genomic Sciences and Icahn Institute of Genomic Sciences, Icahn School of Medicine at Mount Sinai, New York, NY 10029 USA ,Sema4, a Mount Sinai venture, Stamford, CT 06902 USA
| | - Bin Zhang
- Department of Genetics and Genomic Sciences and Icahn Institute of Genomic Sciences, Icahn School of Medicine at Mount Sinai, New York, NY, 10029, USA.
| | - Sam Gandy
- Department of Neurology, Icahn School of Medicine at Mount Sinai, New York, NY, 10029, USA. .,Department of Psychiatry and Alzheimer's Disease Research Center, Icahn School of Medicine at Mount Sinai, New York, NY, 10029, USA.
| | - Michelle E. Ehrlich
- 0000 0001 0670 2351grid.59734.3cDepartment of Neurology, Icahn School of Medicine at Mount Sinai, New York, NY 10029 USA ,0000 0001 0670 2351grid.59734.3cDepartment of Genetics and Genomic Sciences and Icahn Institute of Genomic Sciences, Icahn School of Medicine at Mount Sinai, New York, NY 10029 USA ,0000 0001 0670 2351grid.59734.3cDepartment of Pediatrics, Icahn School of Medicine at Mount Sinai, New York, NY 10029 USA
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11
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Haure-Mirande JV, Audrain M, Fanutza T, Kim SH, Klein WL, Glabe C, Readhead B, Dudley JT, Blitzer RD, Wang M, Zhang B, Schadt EE, Gandy S, Ehrlich ME. Deficiency of TYROBP, an adapter protein for TREM2 and CR3 receptors, is neuroprotective in a mouse model of early Alzheimer's pathology. Acta Neuropathol 2017; 134:769-788. [PMID: 28612290 PMCID: PMC5645450 DOI: 10.1007/s00401-017-1737-3] [Citation(s) in RCA: 74] [Impact Index Per Article: 10.6] [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: 02/20/2017] [Revised: 05/21/2017] [Accepted: 06/02/2017] [Indexed: 01/28/2023]
Abstract
Conventional genetic approaches and computational strategies have converged on immune-inflammatory pathways as key events in the pathogenesis of late onset sporadic Alzheimer’s disease (LOAD). Mutations and/or differential expression of microglial specific receptors such as TREM2, CD33, and CR3 have been associated with strong increased risk for developing Alzheimer’s disease (AD). DAP12 (DNAX-activating protein 12)/TYROBP, a molecule localized to microglia, is a direct partner/adapter for TREM2, CD33, and CR3. We and others have previously shown that TYROBP expression is increased in AD patients and in mouse models. Moreover, missense mutations in the coding region of TYROBP have recently been identified in some AD patients. These lines of evidence, along with computational analysis of LOAD brain gene expression, point to DAP12/TYROBP as a potential hub or driver protein in the pathogenesis of AD. Using a comprehensive panel of biochemical, physiological, behavioral, and transcriptomic assays, we evaluated in a mouse model the role of TYROBP in early stage AD. We crossed an Alzheimer’s model mutant APPKM670/671NL/PSEN1Δexon9(APP/PSEN1) mouse model with Tyrobp−/− mice to generate AD model mice deficient or null for TYROBP (APP/PSEN1; Tyrobp+/− or APP/PSEN1; Tyrobp−/−). While we observed relatively minor effects of TYROBP deficiency on steady-state levels of amyloid-β peptides, there was an effect of Tyrobp deficiency on the morphology of amyloid deposits resembling that reported by others for Trem2−/− mice. We identified modulatory effects of TYROBP deficiency on the level of phosphorylation of TAU that was accompanied by a reduction in the severity of neuritic dystrophy. TYROBP deficiency also altered the expression of several AD related genes, including Cd33. Electrophysiological abnormalities and learning behavior deficits associated with APP/PSEN1 transgenes were greatly attenuated on a Tyrobp-null background. Some modulatory effects of TYROBP on Alzheimer’s-related genes were only apparent on a background of mice with cerebral amyloidosis due to overexpression of mutant APP/PSEN1. These results suggest that reduction of TYROBP gene expression and/or protein levels could represent an immune-inflammatory therapeutic opportunity for modulating early stage LOAD, potentially leading to slowing or arresting the progression to full-blown clinical and pathological LOAD.
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Affiliation(s)
| | - Mickael Audrain
- Department of Neurology, Icahn School of Medicine at Mount Sinai, New York, NY, 10029, USA
| | - Tomas Fanutza
- Department of Neurology, Icahn School of Medicine at Mount Sinai, New York, NY, 10029, USA
| | - Soong Ho Kim
- Department of Neurology, Icahn School of Medicine at Mount Sinai, New York, NY, 10029, USA
| | - William L Klein
- Department of Biochemistry, Northwestern University, Chicago, IL, 60611, USA
| | - Charles Glabe
- Department of Biochemistry and Molecular Biology, University of California at Irvine, Irvine, CA, 92697, USA
| | - Ben Readhead
- Department of Genetics and Genomic Sciences, Icahn Institute of Genomic Sciences, Icahn School of Medicine at Mount Sinai, New York, NY, 10029, USA
| | - Joel T Dudley
- Department of Genetics and Genomic Sciences, Icahn Institute of Genomic Sciences, Icahn School of Medicine at Mount Sinai, New York, NY, 10029, USA
| | - Robert D Blitzer
- Department of Neuroscience, Icahn School of Medicine at Mount Sinai, New York, NY, 10029, USA
| | - Minghui Wang
- Department of Genetics and Genomic Sciences, Icahn Institute of Genomic Sciences, Icahn School of Medicine at Mount Sinai, New York, NY, 10029, USA
| | - Bin Zhang
- Department of Genetics and Genomic Sciences, Icahn Institute of Genomic Sciences, Icahn School of Medicine at Mount Sinai, New York, NY, 10029, USA
| | - Eric E Schadt
- Department of Genetics and Genomic Sciences, Icahn Institute of Genomic Sciences, Icahn School of Medicine at Mount Sinai, New York, NY, 10029, USA
| | - Sam Gandy
- Department of Neurology, Icahn School of Medicine at Mount Sinai, New York, NY, 10029, USA.
- Department of Psychiatry and Alzheimer's Disease Research Center, Icahn School of Medicine at Mount Sinai, New York, NY, 10029, USA.
| | - Michelle E Ehrlich
- Department of Neurology, Icahn School of Medicine at Mount Sinai, New York, NY, 10029, USA.
- Department of Pediatrics, Icahn School of Medicine at Mount Sinai, New York, NY, 10029, USA.
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Travaglia A, Bisaz R, Sweet ES, Blitzer RD, Alberini CM. Erratum: Infantile amnesia reflects a developmental critical period for hippocampal learning. Nat Neurosci 2017; 20:1033. [DOI: 10.1038/nn0717-1033a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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13
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Travaglia A, Bisaz R, Sweet ES, Blitzer RD, Alberini CM. Infantile amnesia reflects a developmental critical period for hippocampal learning. Nat Neurosci 2016; 19:1225-33. [PMID: 27428652 PMCID: PMC5003643 DOI: 10.1038/nn.4348] [Citation(s) in RCA: 103] [Impact Index Per Article: 12.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2016] [Accepted: 06/24/2016] [Indexed: 02/07/2023]
Abstract
Episodic memories formed during the first postnatal period are rapidly forgotten, a phenomenon known as infantile amnesia. In spite of this memory loss, early experiences influence adult behavior, raising the question of which mechanisms underlie infantile memories and amnesia. Here we show that in rats an experience learned during the infantile amnesia period is stored as a latent memory trace for a long time; indeed, a later reminder reinstates a robust, context-specific and long-lasting memory. The formation and storage of this latent memory requires the hippocampus, follows a sharp temporal boundary, and occurs through mechanisms typical of developmental critical periods, including brain-derived-neurotrophic-factor (BDNF)- and metabotropic-glutamate-receptor-5 (mGluR5)-dependent expression switch of the N-methyl-D-aspartate receptor subunits 2B-2A. BDNF or mGlur5 activation after training rescues the infantile amnesia. Thus, early episodic memories are not lost, but remain stored long-term. These data suggest that the hippocampus undergoes a developmental critical period to become functionally competent.
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Affiliation(s)
- Alessio Travaglia
- Center for Neural Science, New York University, New York, New York, USA
| | - Reto Bisaz
- Center for Neural Science, New York University, New York, New York, USA
| | - Eric S Sweet
- Department of Pharmacological Sciences, Icahn School of Medicine at Mount Sinai, New York, New York, USA.,Department of Neurology, Icahn School of Medicine at Mount Sinai, New York, New York, USA
| | - Robert D Blitzer
- Department of Pharmacological Sciences, Icahn School of Medicine at Mount Sinai, New York, New York, USA.,Department of Psychiatry, Icahn School of Medicine at Mount Sinai, New York, New York, USA
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Wang J, Varghese M, Ono K, Yamada M, Levine S, Tzavaras N, Gong B, Hurst WJ, Blitzer RD, Pasinetti GM. Cocoa extracts reduce oligomerization of amyloid-β: implications for cognitive improvement in Alzheimer's disease. J Alzheimers Dis 2015; 41:643-50. [PMID: 24957018 DOI: 10.3233/jad-132231] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
BACKGROUND Alzheimer's disease (AD) is the most common age-related neurodegenerative disorder, characterized by pathological aggregates of amyloid peptide-β (Aβ) and tau protein. Currently available therapies mediate AD symptoms without modifying disease progression. Polyphenol-rich diets are reported to reduce the risk for AD. OBJECTIVE In the present study, we investigated the AD disease-modifying effects of cocoa, a rich source of flavanols, which are a class of polyphenols. We hypothesized that cocoa extracts interfere with amyloid-β oligomerization to prevent synaptic deficits. METHODS We tested the effects of three different cocoa extracts, viz. Natural, Dutched, and Lavado extracts, on Aβ42 and Aβ40 oligomerization, using photo-induced cross-linking of unmodified proteins technique. To assess the effects of cocoa extracts on synaptic function, we measured long term potentiation in mouse brain hippocampal slices exposed to oligomeric Aβ. RESULTS Our results indicate that cocoa extracts are effective in preventing the oligomerization of Aβ, with Lavado extract being most effective. Lavado extract, but not Dutched extract, was effective in restoring the long term potentiation response reduced by oligomeric Aβ. CONCLUSION Our findings indicate that cocoa extracts have multiple disease-modifying properties in AD and present a promising route of therapeutic and/or preventative initiatives.
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Affiliation(s)
- Jun Wang
- Department of Neurology, Icahn School of Medicine at Mount Sinai, New York, NY, USA Geriatric Research, Education and Clinical Center, James J. Peters Veterans Affairs Medical Center, Bronx, NY, USA
| | - Merina Varghese
- Department of Neurology, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Kenjiro Ono
- Department of Neurology and Neurobiology and Aging, Kanazawa University Graduate School of Medical Science, Kanazawa, Japan
| | - Masahito Yamada
- Department of Neurology and Neurobiology and Aging, Kanazawa University Graduate School of Medical Science, Kanazawa, Japan
| | - Samara Levine
- Department of Neurology, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Nikos Tzavaras
- Department of Pharmacology and System Therapeutics, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Bing Gong
- Department of Neurology, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - William J Hurst
- The Hershey Center of Health and Nutrition, The Hershey Company, Hershey, PA, USA
| | - Robert D Blitzer
- Department of Pharmacology and System Therapeutics, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Giulio Maria Pasinetti
- Department of Neurology, Icahn School of Medicine at Mount Sinai, New York, NY, USA Geriatric Research, Education and Clinical Center, James J. Peters Veterans Affairs Medical Center, Bronx, NY, USA
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15
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Szutorisz H, DiNieri JA, Sweet E, Egervari G, Michaelides M, Carter JM, Ren Y, Miller ML, Blitzer RD, Hurd YL. Parental THC exposure leads to compulsive heroin-seeking and altered striatal synaptic plasticity in the subsequent generation. Neuropsychopharmacology 2014; 39:1315-23. [PMID: 24385132 PMCID: PMC3988557 DOI: 10.1038/npp.2013.352] [Citation(s) in RCA: 132] [Impact Index Per Article: 13.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/20/2013] [Revised: 12/09/2013] [Accepted: 12/10/2013] [Indexed: 12/20/2022]
Abstract
Recent attention has been focused on the long-term impact of cannabis exposure, for which experimental animal studies have validated causal relationships between neurobiological and behavioral alterations during the individual's lifetime. Here, we show that adolescent exposure to Δ(9)-tetrahydrocannabinol (THC), the main psychoactive component of cannabis, results in behavioral and neurobiological abnormalities in the subsequent generation of rats as a consequence of parental germline exposure to the drug. Adult F1 offspring that were themselves unexposed to THC displayed increased work effort to self-administer heroin, with enhanced stereotyped behaviors during the period of acute heroin withdrawal. On the molecular level, parental THC exposure was associated with changes in the mRNA expression of cannabinoid, dopamine, and glutamatergic receptor genes in the striatum, a key component of the neuronal circuitry mediating compulsive behaviors and reward sensitivity. Specifically, decreased mRNA and protein levels, as well as NMDA receptor binding were observed in the dorsal striatum of adult offspring as a consequence of germline THC exposure. Electrophysiologically, plasticity was altered at excitatory synapses of the striatal circuitry that is known to mediate compulsive and goal-directed behaviors. These findings demonstrate that parental history of germline THC exposure affects the molecular characteristics of the striatum, can impact offspring phenotype, and could possibly confer enhanced risk for psychiatric disorders in the subsequent generation.
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Affiliation(s)
- Henrietta Szutorisz
- Department of Psychiatry, Icahn School of Medicine at Mount Sinai, New York, NY, USA,Department of Neuroscience, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Jennifer A DiNieri
- Department of Psychiatry, Icahn School of Medicine at Mount Sinai, New York, NY, USA,Department of Neuroscience, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Eric Sweet
- Department of Neurology, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Gabor Egervari
- Department of Psychiatry, Icahn School of Medicine at Mount Sinai, New York, NY, USA,Department of Neuroscience, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Michael Michaelides
- Department of Psychiatry, Icahn School of Medicine at Mount Sinai, New York, NY, USA,Department of Neuroscience, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Jenna M Carter
- Department of Psychiatry, Icahn School of Medicine at Mount Sinai, New York, NY, USA,Department of Neuroscience, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Yanhua Ren
- Department of Psychiatry, Icahn School of Medicine at Mount Sinai, New York, NY, USA,Department of Neuroscience, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Michael L Miller
- Department of Psychiatry, Icahn School of Medicine at Mount Sinai, New York, NY, USA,Department of Neuroscience, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Robert D Blitzer
- Department of Psychiatry, Icahn School of Medicine at Mount Sinai, New York, NY, USA,Department of Pharmacology and Systems Therapeutics, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Yasmin L Hurd
- Department of Psychiatry, Icahn School of Medicine at Mount Sinai, New York, NY, USA,Department of Neuroscience, Icahn School of Medicine at Mount Sinai, New York, NY, USA,James J Peters Veterans Medical Center, Bronx, NY, USA,Departments of Psychiatry and Neuroscience, Icahn School of Medicine at Mount Sinai, One Gustave L. Levy Place, Box 1065, New York, NY 10029, USA, Tel.: +1 212 824 8314, Fax: +1 646 527 9598, E-mail:
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16
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Gaidamakov S, Maximova OA, Chon H, Blewett NH, Wang H, Crawford AK, Day A, Tulchin N, Crouch RJ, Morse HC, Blitzer RD, Maraia RJ. Targeted deletion of the gene encoding the La autoantigen (Sjögren's syndrome antigen B) in B cells or the frontal brain causes extensive tissue loss. Mol Cell Biol 2014; 34:123-31. [PMID: 24190965 PMCID: PMC3911279 DOI: 10.1128/mcb.01010-13] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [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: 08/06/2013] [Revised: 09/09/2013] [Accepted: 10/23/2013] [Indexed: 11/20/2022] Open
Abstract
La antigen (Sjögren's syndrome antigen B) is a phosphoprotein associated with nascent precursor tRNAs and other RNAs, and it is targeted by autoantibodies in patients with Sjögren's syndrome, systemic lupus erythematosus, and neonatal lupus. Increased levels of La are associated with leukemias and other cancers, and various viruses usurp La to promote their replication. Yeast cells (Saccharomyces cerevisiae and Schizosaccharomyces pombe) genetically depleted of La grow and proliferate, whereas deletion from mice causes early embryonic lethality, raising the question of whether La is required by mammalian cells generally or only to surpass a developmental stage. We developed a conditional La allele and used it in mice that express Cre recombinase in either B cell progenitors or the forebrain. B cell Mb1(Cre) La-deleted mice produce no B cells. Consistent with αCamKII Cre, which induces deletion in hippocampal CA1 cells in the third postnatal week and later throughout the neocortex, brains develop normally in La-deleted mice until ∼5 weeks and then lose a large amount of forebrain cells and mass, with evidence of altered pre-tRNA processing. The data indicate that La is required not only in proliferating cells but also in nondividing postmitotic cells. Thus, La is essential in different cell types and required for normal development of various tissue types.
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Affiliation(s)
- Sergei Gaidamakov
- Intramural Research Programs of the Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland, USA
| | - Olga A. Maximova
- Laboratory of Infectious Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, USA
| | - Hyongi Chon
- Intramural Research Programs of the Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland, USA
| | - Nathan H. Blewett
- Intramural Research Programs of the Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland, USA
| | - Hongsheng Wang
- Laboratory of Immunogenetics, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, USA
| | - Amanda K. Crawford
- Intramural Research Programs of the Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland, USA
| | - Amanda Day
- Intramural Research Programs of the Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland, USA
| | - Natalie Tulchin
- Department of Pathology, Mount Sinai School of Medicine, New York, New York, USA
| | - Robert J. Crouch
- Intramural Research Programs of the Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland, USA
| | - Herbert C. Morse
- Laboratory of Immunogenetics, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, USA
| | - Robert D. Blitzer
- Department of Pharmacology and Systems Therapeutics, Mount Sinai School of Medicine, New York, New York, USA
| | - Richard J. Maraia
- Intramural Research Programs of the Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland, USA
- Commissioned Corps, U.S. Public Health Service, Washington, DC, USA
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Rozenfeld R, Bushlin I, Gomes I, Tzavaras N, Gupta A, Neves S, Battini L, Gusella GL, Lachmann A, Ma'ayan A, Blitzer RD, Devi LA. Receptor heteromerization expands the repertoire of cannabinoid signaling in rodent neurons. PLoS One 2012; 7:e29239. [PMID: 22235275 PMCID: PMC3250422 DOI: 10.1371/journal.pone.0029239] [Citation(s) in RCA: 60] [Impact Index Per Article: 5.0] [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: 05/05/2011] [Accepted: 11/23/2011] [Indexed: 11/18/2022] Open
Abstract
A fundamental question in G protein coupled receptor biology is how a single ligand acting at a specific receptor is able to induce a range of signaling that results in a variety of physiological responses. We focused on Type 1 cannabinoid receptor (CB1R) as a model GPCR involved in a variety of processes spanning from analgesia and euphoria to neuronal development, survival and differentiation. We examined receptor dimerization as a possible mechanism underlying expanded signaling responses by a single ligand and focused on interactions between CB1R and delta opioid receptor (DOR). Using co-immunoprecipitation assays as well as analysis of changes in receptor subcellular localization upon co-expression, we show that CB1R and DOR form receptor heteromers. We find that heteromerization affects receptor signaling since the potency of the CB1R ligand to stimulate G-protein activity is increased in the absence of DOR, suggesting that the decrease in CB1R activity in the presence of DOR could, at least in part, be due to heteromerization. We also find that the decrease in activity is associated with enhanced PLC-dependent recruitment of arrestin3 to the CB1R-DOR complex, suggesting that interaction with DOR enhances arrestin-mediated CB1R desensitization. Additionally, presence of DOR facilitates signaling via a new CB1R-mediated anti-apoptotic pathway leading to enhanced neuronal survival. Taken together, these results support a role for CB1R-DOR heteromerization in diversification of endocannabinoid signaling and highlight the importance of heteromer-directed signal trafficking in enhancing the repertoire of GPCR signaling.
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Affiliation(s)
- Raphael Rozenfeld
- Department of Pharmacology and Systems Therapeutics, Mount Sinai School of Medicine, New York, New York, United States of America
| | - Ittai Bushlin
- Department of Pharmacology and Systems Therapeutics, Mount Sinai School of Medicine, New York, New York, United States of America
- Department of Neuroscience and The Friedman Brain Institute, Mount Sinai School of Medicine, New York, New York, United States of America
| | - Ivone Gomes
- Department of Pharmacology and Systems Therapeutics, Mount Sinai School of Medicine, New York, New York, United States of America
| | - Nikos Tzavaras
- Department of Pharmacology and Systems Therapeutics, Mount Sinai School of Medicine, New York, New York, United States of America
| | - Achla Gupta
- Department of Pharmacology and Systems Therapeutics, Mount Sinai School of Medicine, New York, New York, United States of America
| | - Susana Neves
- Department of Pharmacology and Systems Therapeutics, Mount Sinai School of Medicine, New York, New York, United States of America
- Systems Biology Center of New York, Mount Sinai School of Medicine, New York, New York, United States of America
| | - Lorenzo Battini
- Department of Medicine, Mount Sinai School of Medicine, New York, New York, United States of America
| | - G. Luca Gusella
- Department of Medicine, Mount Sinai School of Medicine, New York, New York, United States of America
| | - Alexander Lachmann
- Department of Pharmacology and Systems Therapeutics, Mount Sinai School of Medicine, New York, New York, United States of America
- Systems Biology Center of New York, Mount Sinai School of Medicine, New York, New York, United States of America
| | - Avi Ma'ayan
- Department of Pharmacology and Systems Therapeutics, Mount Sinai School of Medicine, New York, New York, United States of America
- Systems Biology Center of New York, Mount Sinai School of Medicine, New York, New York, United States of America
| | - Robert D. Blitzer
- Department of Pharmacology and Systems Therapeutics, Mount Sinai School of Medicine, New York, New York, United States of America
- Systems Biology Center of New York, Mount Sinai School of Medicine, New York, New York, United States of America
| | - Lakshmi A. Devi
- Department of Pharmacology and Systems Therapeutics, Mount Sinai School of Medicine, New York, New York, United States of America
- Department of Neuroscience and The Friedman Brain Institute, Mount Sinai School of Medicine, New York, New York, United States of America
- Systems Biology Center of New York, Mount Sinai School of Medicine, New York, New York, United States of America
- * E-mail:
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18
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Wu Y, Bauman WA, Blitzer RD, Cardozo C. Testosterone-induced hypertrophy of L6 myoblasts is dependent upon Erk and mTOR. Biochem Biophys Res Commun 2010; 400:679-83. [DOI: 10.1016/j.bbrc.2010.08.127] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2010] [Accepted: 08/27/2010] [Indexed: 01/09/2023]
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19
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Ma T, Hoeffer CA, Capetillo-Zarate E, Yu F, Wong H, Lin MT, Tampellini D, Klann E, Blitzer RD, Gouras GK. Dysregulation of the mTOR pathway mediates impairment of synaptic plasticity in a mouse model of Alzheimer's disease. PLoS One 2010; 5. [PMID: 20862226 PMCID: PMC2942840 DOI: 10.1371/journal.pone.0012845] [Citation(s) in RCA: 178] [Impact Index Per Article: 12.7] [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: 06/09/2010] [Accepted: 08/16/2010] [Indexed: 01/22/2023] Open
Abstract
Background The mammalian target of rapamycin (mTOR) is an evolutionarily conserved Ser/Thr protein kinase that plays a pivotal role in multiple fundamental biological processes, including synaptic plasticity. We explored the relationship between the mTOR pathway and β-amyloid (Aβ)-induced synaptic dysfunction, which is considered to be critical in the pathogenesis of Alzheimer's disease (AD). Methodology/Principal Findings We provide evidence that inhibition of mTOR signaling correlates with impairment in synaptic plasticity in hippocampal slices from an AD mouse model and in wild-type slices exposed to exogenous Aβ1-42. Importantly, by up-regulating mTOR signaling, glycogen synthase kinase 3 (GSK3) inhibitors rescued LTP in the AD mouse model, and genetic deletion of FK506-binding protein 12 (FKBP12) prevented Aβ-induced impairment in long-term potentiation (LTP). In addition, confocal microscopy demonstrated co-localization of intraneuronal Aβ42 with mTOR. Conclusions/Significance These data support the notion that the mTOR pathway modulates Aβ-related synaptic dysfunction in AD.
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Affiliation(s)
- Tao Ma
- Department of Neurology and Neuroscience, Weill Cornell Medical College, New York, New York, United States of America
| | - Charles A. Hoeffer
- Center for Neural Science, New York University, New York, New York, United States of America
| | - Estibaliz Capetillo-Zarate
- Department of Neurology and Neuroscience, Weill Cornell Medical College, New York, New York, United States of America
| | - Fangmin Yu
- Department of Neurology and Neuroscience, Weill Cornell Medical College, New York, New York, United States of America
| | - Helen Wong
- Center for Neural Science, New York University, New York, New York, United States of America
| | - Michael T. Lin
- Department of Neurology and Neuroscience, Weill Cornell Medical College, New York, New York, United States of America
| | - Davide Tampellini
- Department of Neurology and Neuroscience, Weill Cornell Medical College, New York, New York, United States of America
| | - Eric Klann
- Center for Neural Science, New York University, New York, New York, United States of America
| | - Robert D. Blitzer
- Department of Pharmacology and Systems Therapeutics, Mount Sinai School of Medicine, New York, New York, United States of America
| | - Gunnar K. Gouras
- Department of Neurology and Neuroscience, Weill Cornell Medical College, New York, New York, United States of America
- Rockefeller University, New York, New York, United States of America
- * E-mail:
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20
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Wu Y, Zhao W, Zhao J, Zhang Y, Qin W, Pan J, Bauman WA, Blitzer RD, Cardozo C. REDD1 is a major target of testosterone action in preventing dexamethasone-induced muscle loss. Endocrinology 2010; 151:1050-9. [PMID: 20032058 PMCID: PMC2840688 DOI: 10.1210/en.2009-0530] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.8] [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: 01/22/2023]
Abstract
Glucocorticoids are a well-recognized and common cause of muscle atrophy that can be prevented by testosterone. However, the molecular mechanisms underlying such protection have not been described. Thus, the global effects of testosterone on dexamethasone-induced changes in gene expression were evaluated in rat gastrocnemius muscle using DNA microarrays. Gene expression was analyzed after 7-d administration of dexamethasone, dexamethasone plus testosterone, or vehicle. Dexamethasone changed expression of 876 probe sets by at least 2-fold. Among these, 474 probe sets were changed by at least 2-fold in the opposite direction in the dexamethasone plus testosterone group (genes in opposition). Major biological themes represented by genes in opposition included IGF-I signaling, myogenesis and muscle development, and cell cycle progression. Testosterone completely prevented the 22-fold increase in expression of the mammalian target of rapamycin (mTOR) inhibitor regulated in development and DNA damage responses 1 (REDD1), and attenuated dexamethasone induced increased expression of eIF4E binding protein 1, Forkhead box O1, and the p85 regulatory subunit of the IGF-I receptor but prevented decreased expression of IRS-1. Testosterone attenuated increases in REDD1 protein in skeletal muscle and L6 myoblasts and prevented dephosphorylation of p70S6 kinase at the mTOR-dependent site Thr389 in L6 myoblast cells. Effects of testosterone on REDD1 mRNA levels occurred within 1 h, required the androgen receptor, were blocked by bicalutamide, and were due to inhibition of transcriptional activation of REDD1 by dexamethasone. These data suggest that testosterone blocks dexamethasone-induced changes in expression of REDD1 and other genes that collectively would otherwise down-regulate mTOR activity and hence also down-regulate protein synthesis.
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Affiliation(s)
- Yong Wu
- Center of Excellence for the Medical Consequences of Spinal Cord Injury, James J. Peters VA Medical Center, 953 Southern Boulevard, Bronx, New York 10468, USA
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21
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Neves SR, Tsokas P, Sarkar A, Grace EA, Rangamani P, Taubenfeld SM, Alberini CM, Schaff JC, Blitzer RD, Moraru II, Iyengar R. Cell shape and negative links in regulatory motifs together control spatial information flow in signaling networks. Cell 2008; 133:666-80. [PMID: 18485874 PMCID: PMC2728678 DOI: 10.1016/j.cell.2008.04.025] [Citation(s) in RCA: 199] [Impact Index Per Article: 12.4] [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: 05/10/2007] [Revised: 01/30/2008] [Accepted: 04/10/2008] [Indexed: 11/19/2022]
Abstract
The role of cell size and shape in controlling local intracellular signaling reactions, and how this spatial information originates and is propagated, is not well understood. We have used partial differential equations to model the flow of spatial information from the beta-adrenergic receptor to MAPK1,2 through the cAMP/PKA/B-Raf/MAPK1,2 network in neurons using real geometries. The numerical simulations indicated that cell shape controls the dynamics of local biochemical activity of signal-modulated negative regulators, such as phosphodiesterases and protein phosphatases within regulatory loops to determine the size of microdomains of activated signaling components. The model prediction that negative regulators control the flow of spatial information to downstream components was verified experimentally in rat hippocampal slices. These results suggest a mechanism by which cellular geometry, the presence of regulatory loops with negative regulators, and key reaction rates all together control spatial information transfer and microdomain characteristics within cells.
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Affiliation(s)
- Susana R. Neves
- Department of Pharmacology and Systems Therapeutics, Mount Sinai School of Medicine, One Gustave L. Levy Place, Box 1215, New York, NY 10029, USA
| | - Panayiotis Tsokas
- Department of Pharmacology and Systems Therapeutics, Mount Sinai School of Medicine, One Gustave L. Levy Place, Box 1215, New York, NY 10029, USA
| | - Anamika Sarkar
- Department of Pharmacology and Systems Therapeutics, Mount Sinai School of Medicine, One Gustave L. Levy Place, Box 1215, New York, NY 10029, USA
| | - Elizabeth A. Grace
- Department of Pharmacology and Systems Therapeutics, Mount Sinai School of Medicine, One Gustave L. Levy Place, Box 1215, New York, NY 10029, USA
| | - Padmini Rangamani
- Department of Pharmacology and Systems Therapeutics, Mount Sinai School of Medicine, One Gustave L. Levy Place, Box 1215, New York, NY 10029, USA
| | - Stephen M. Taubenfeld
- Department of Neuroscience, Mount Sinai School of Medicine, One Gustave L. Levy Place, Box 1215, New York, NY 10029, USA
| | - Cristina M. Alberini
- Department of Neuroscience, Mount Sinai School of Medicine, One Gustave L. Levy Place, Box 1215, New York, NY 10029, USA
| | - James C. Schaff
- Center for Cell Analysis and Modeling, University of Connecticut Health Center Farmington, CT 06030, USA
| | - Robert D. Blitzer
- Department of Pharmacology and Systems Therapeutics, Mount Sinai School of Medicine, One Gustave L. Levy Place, Box 1215, New York, NY 10029, USA
| | - Ion I. Moraru
- Center for Cell Analysis and Modeling, University of Connecticut Health Center Farmington, CT 06030, USA
| | - Ravi Iyengar
- Department of Pharmacology and Systems Therapeutics, Mount Sinai School of Medicine, One Gustave L. Levy Place, Box 1215, New York, NY 10029, USA
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22
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Tsokas P, Ma T, Iyengar R, Landau EM, Blitzer RD. Mitogen-activated protein kinase upregulates the dendritic translation machinery in long-term potentiation by controlling the mammalian target of rapamycin pathway. J Neurosci 2007; 27:5885-94. [PMID: 17537959 PMCID: PMC6672260 DOI: 10.1523/jneurosci.4548-06.2007] [Citation(s) in RCA: 142] [Impact Index Per Article: 8.4] [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] [Indexed: 02/02/2023] Open
Abstract
Protein synthesis is required for persistent forms of synaptic plasticity, including long-term potentiation (LTP). A key regulator of LTP-related protein synthesis is mammalian target of rapamycin (mTOR), which is thought to modulate translational capacity by facilitating the synthesis of particular components of the protein synthesis machinery. Recently, extracellularly regulated kinase (ERK) also was shown to mediate plasticity-related translation, an effect that may involve regulation of the mTOR pathway. We studied the interaction between the mTOR and ERK pathways in hippocampal LTP induced at CA3-CA1 synapses by high-frequency synaptic stimulation (HFS). Within minutes after HFS, the expression of multiple translational proteins, the synthesis of which is under the control of mTOR, increased in area CA1 stratum radiatum. This upregulation was detected in pyramidal cell dendrites and was blocked by inhibitors of the ERK pathway. In addition, ERK mediated the stimulation of mTOR by HFS. The possibility that ERK regulates mTOR by acting at a component further upstream in the phosphatidylinositide 3-kinase (PI3K)-mTOR pathway was tested by probing the phosphorylation of p90-S6 kinase, phosphoinositide-dependent kinase 1 (PDK1), and Akt. ERK inhibitors blocked HFS-induced phosphorylation of all three proteins at sites implicated in the regulation of mTOR. Moreover, a component of basal and HFS-induced ERK activity depended on PI3K, indicating that mTOR-mediated protein synthesis in LTP requires coincident and mutually dependent activity in the PI3K and ERK pathways. The role of ERK in regulating PDK1 and Akt, with their extensive effects on cellular function, has important implications for the coordinated response of the neuron to LTP-inducing stimulation.
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Affiliation(s)
| | - Tao Ma
- Departments of Pharmacology and Biological Chemistry and
| | - Ravi Iyengar
- Departments of Pharmacology and Biological Chemistry and
| | - Emmanuel M. Landau
- Departments of Pharmacology and Biological Chemistry and
- Psychiatry, Mount Sinai School of Medicine, New York, New York 10029, and
- Psychiatry Service, Bronx Veterans Administration Medical Center, Bronx, New York 10463
| | - Robert D. Blitzer
- Departments of Pharmacology and Biological Chemistry and
- Psychiatry, Mount Sinai School of Medicine, New York, New York 10029, and
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23
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Tsokas P, Grace EA, Chan P, Ma T, Sealfon SC, Iyengar R, Landau EM, Blitzer RD. Local protein synthesis mediates a rapid increase in dendritic elongation factor 1A after induction of late long-term potentiation. J Neurosci 2006; 25:5833-43. [PMID: 15958750 PMCID: PMC6724870 DOI: 10.1523/jneurosci.0599-05.2005] [Citation(s) in RCA: 194] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023] Open
Abstract
The maintenance of long-term potentiation (LTP) requires a brief period of accelerated protein synthesis soon after synaptic stimulation, suggesting that an early phase of enhanced translation contributes to stable LTP. The mechanism regulating protein synthesis and the location and identities of mRNAs translated are not well understood. Here, we show in acute brain slices that the induction of protein synthesis-dependent hippocampal LTP increases the expression of elongation factor 1A (eEF1A), the mRNA of which contains a 5' terminal oligopyrimidine tract. This effect is blocked by rapamycin, indicating that the increase in EF1A expression is mediated by the mammalian target of rapamycin (mTOR) pathway. We find that mRNA for eEF1A is present in pyramidal cell dendrites and that the LTP-associated increase in eEF1A expression was intact in dendrites that had been severed from their cell bodies before stimulation. eEF1A levels increased within 5 min after stimulation in a translation-dependent manner, and this effect remained stable for 3 h. These results suggest a mechanism whereby synaptic stimulation, by signaling through the mTOR pathway, produces an increase in dendritic translational capacity that contributes to LTP maintenance.
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Affiliation(s)
- Panayiotis Tsokas
- Department of Pharmacology and Biological Chemistry, Mount Sinai School of Medicine, New York, New York 10029, USA
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24
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Abstract
Synapses in general exhibit various forms of plasticity; that is, the efficiency of transmission across the synapse can be potentiated or depressed in response to a prior history of stimulation. The persistence of the change in efficiency can be relatively brief, exemplified by post-tetanic potentiation (PTP), which decays within a few seconds. At the other extreme, very stable forms of plasticity, long-term potentiation (LTP) and long-term depression (LTD), can be established at many synapses in the brain. LTP is often proposed as a candidate for the cellular basis of memory, but direct evidence for this hypothesis is lacking. That said, a large body of research has provided correlative evidence for LTP as a process that underlies memory formation. This lecture, which is a part of the course "Cell Signaling Systems: A Course for Graduate Students," describes LTP from a cell biological perspective. Topics include the signaling network responsible for LTP induction, evidence for upregulated postsynaptic mechanisms in LTP, and the role of gene expression regulation, at the transcriptional and translational levels, in the maintenance of LTP.
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Affiliation(s)
- Robert D Blitzer
- Department of Pharmacology and Biological Chemistry, Mount Sinai School of Medicine, New York, NY 10029, USA.
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25
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Ma’ayan A, Jenkins SL, Neves S, Hasseldine A, Grace E, Dubin-Thaler B, Eungdamrong NJ, Weng G, Ram PT, Rice JJ, Kershenbaum A, Stolovitzky GA, Blitzer RD, Iyengar R. Formation of regulatory patterns during signal propagation in a Mammalian cellular network. Science 2005; 309:1078-83. [PMID: 16099987 PMCID: PMC3032439 DOI: 10.1126/science.1108876] [Citation(s) in RCA: 261] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
We developed a model of 545 components (nodes) and 1259 interactions representing signaling pathways and cellular machines in the hippocampal CA1 neuron. Using graph theory methods, we analyzed ligand-induced signal flow through the system. Specification of input and output nodes allowed us to identify functional modules. Networking resulted in the emergence of regulatory motifs, such as positive and negative feedback and feedforward loops, that process information. Key regulators of plasticity were highly connected nodes required for the formation of regulatory motifs, indicating the potential importance of such motifs in determining cellular choices between homeostasis and plasticity.
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Affiliation(s)
- Avi Ma’ayan
- Department of Pharmacology and Biological Chemistry, Mount Sinai School of Medicine, New York, NY 10029, USA
| | - Sherry L. Jenkins
- Department of Pharmacology and Biological Chemistry, Mount Sinai School of Medicine, New York, NY 10029, USA
| | - Susana Neves
- Department of Pharmacology and Biological Chemistry, Mount Sinai School of Medicine, New York, NY 10029, USA
| | - Anthony Hasseldine
- Department of Pharmacology and Biological Chemistry, Mount Sinai School of Medicine, New York, NY 10029, USA
| | - Elizabeth Grace
- Department of Pharmacology and Biological Chemistry, Mount Sinai School of Medicine, New York, NY 10029, USA
| | | | - Narat J. Eungdamrong
- Department of Pharmacology and Biological Chemistry, Mount Sinai School of Medicine, New York, NY 10029, USA
| | - Gehzi Weng
- Department of Pharmacology and Biological Chemistry, Mount Sinai School of Medicine, New York, NY 10029, USA
| | - Prahlad T. Ram
- Department of Pharmacology and Biological Chemistry, Mount Sinai School of Medicine, New York, NY 10029, USA
| | - J. Jeremy Rice
- Functional Genomics and Systems Biology, IBM T. J. Watson Research Center, Yorktown Heights, NY 10598, USA
| | - Aaron Kershenbaum
- Functional Genomics and Systems Biology, IBM T. J. Watson Research Center, Yorktown Heights, NY 10598, USA
| | - Gustavo A. Stolovitzky
- Functional Genomics and Systems Biology, IBM T. J. Watson Research Center, Yorktown Heights, NY 10598, USA
| | - Robert D. Blitzer
- Department of Pharmacology and Biological Chemistry, Mount Sinai School of Medicine, New York, NY 10029, USA
- Department of Psychiatry, Mount Sinai School of Medicine, New York, NY 10029, USA
| | - Ravi Iyengar
- Department of Pharmacology and Biological Chemistry, Mount Sinai School of Medicine, New York, NY 10029, USA
- To whom correspondence should be addressed.
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26
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Abstract
Progress in experimental and theoretical biology is likely to provide us with the opportunity to assemble detailed predictive models of mammalian cells. Using a functional format to describe the organization of mammalian cells, we describe current approaches for developing qualitative and quantitative models using data from a variety of experimental sources. Recent developments and applications of graph theory to biological networks are reviewed. The use of these qualitative models to identify the topology of regulatory motifs and functional modules is discussed. Cellular homeostasis and plasticity are interpreted within the framework of balance between regulatory motifs and interactions between modules. From this analysis we identify the need for detailed quantitative models on the basis of the representation of the chemistry underlying the cellular process. The use of deterministic, stochastic, and hybrid models to represent cellular processes is reviewed, and an initial integrated approach for the development of large-scale predictive models of a mammalian cell is presented.
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27
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Blitzer RD, Iyengar R, Landau EM. Postsynaptic signaling networks: cellular cogwheels underlying long-term plasticity. Biol Psychiatry 2005; 57:113-9. [PMID: 15652868 DOI: 10.1016/j.biopsych.2004.02.031] [Citation(s) in RCA: 92] [Impact Index Per Article: 4.8] [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] [Received: 11/12/2003] [Revised: 02/18/2004] [Accepted: 02/26/2004] [Indexed: 10/26/2022]
Abstract
Learning depends on positive or negative changes in synaptic transmission that are synapse-specific and sustained. Synaptic signals can be directly measured and respond to certain kinds of stimulation by becoming persistently enhanced (long-term potentiation, LTP) or decreased (long-term depression, LTD). Studying LTP and LTD opens a window on to the molecular mechanisms of memory. Although changes in both pre- and postsynaptic strength have been implicated in LTP and LTD, most attention has been focused on changes in postsynaptic glutamate receptor density. This is controlled by intracellular Ca(2+) ions via a network of signaling molecules. Changes in postsynaptic Ca(2+) concentration depend on the coincidence of appropriate synaptic signals, as is found in learning situations. The long-term persistence of LTP and LTD requires gene transcription and translation. It is posited that local translation at the synapse, in a self-sustaining manner, mediates the persistence of long-term changes despite constant turnover of the synaptic components.
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Affiliation(s)
- Robert D Blitzer
- Department of Psychiatry, Mount Sinai School of Medicine, New York, New York 10029, USA
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28
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Giovannini MG, Blitzer RD, Wong T, Asoma K, Tsokas P, Morrison JH, Iyengar R, Landau EM. Mitogen-activated protein kinase regulates early phosphorylation and delayed expression of Ca2+/calmodulin-dependent protein kinase II in long-term potentiation. J Neurosci 2001; 21:7053-62. [PMID: 11549715 PMCID: PMC6762991] [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] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2001] [Revised: 06/25/2001] [Accepted: 06/26/2001] [Indexed: 02/21/2023] Open
Abstract
Activation of mitogen-activated protein kinase (MAPK) and Ca(2+)/calmodulin-dependent protein kinase II (CaMKII) are required for numerous forms of neuronal plasticity, including long-term potentiation (LTP). We induced LTP in rat hippocampal area CA1 using theta-pulse stimulation (TPS) paired with beta-adrenergic receptor activation [isoproterenol (ISO)], a protocol that may be particularly relevant to normal patterns of hippocampal activity during learning. This stimulation resulted in a transient phosphorylation of p42 MAPK, and the resulting LTP was MAPK dependent. In addition, CaMKII was regulated in two, temporally distinct ways after TPS-ISO: a transient rise in the fraction of phosphorylated CaMKII and a subsequent persistent increase in CaMKII expression. The increases in MAPK and CaMKII phosphorylation were strongly colocalized in the dendrites and cell bodies of CA1 pyramidal cells, and both the transient phosphorylation and delayed expression of CaMKII were prevented by inhibiting p42/p44 MAPK. These results establish a novel bimodal regulation of CaMKII by MAPK, which may contribute to both post-translational modification and increased gene expression.
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Affiliation(s)
- M G Giovannini
- Department of Pharmacology, Mount Sinai School of Medicine, New York, New York 10029, USA
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29
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Brown GP, Blitzer RD, Connor JH, Wong T, Shenolikar S, Iyengar R, Landau EM. Long-term potentiation induced by theta frequency stimulation is regulated by a protein phosphatase-1-operated gate. J Neurosci 2000; 20:7880-7. [PMID: 11050107 PMCID: PMC6772713] [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] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/18/2023] Open
Abstract
Long-term potentiation (LTP) can be induced in the Schaffer collateral-->CA1 synapse of hippocampus by stimulation in the theta frequency range (5-12 Hz), an effect that depends on activation of the cAMP pathway. We investigated the mechanisms of the cAMP contribution to this form of LTP in the rat hippocampal slice preparation. theta pulse stimulation (TPS; 150 stimuli at 10 Hz) by itself did not induce LTP, but the addition of either the beta-adrenergic agonist isoproterenol or the cAMP analog 8-bromo-cAMP (8-Br-cAMP) enabled TPS-induced LTP. The isoproterenol effect was blocked by postsynaptic inhibition of cAMP-dependent protein kinase. Several lines of evidence indicated that cAMP enabled LTP by blocking postsynaptic protein phosphatase-1 (PP1). Activators of the cAMP pathway reduced PP1 activity in the CA1 region and increased the active form of inhibitor-1, an endogenous inhibitor of PP1. Postsynaptic injection of activated inhibitor-1 mimicked the LTP-enabling effect of cAMP pathway stimulation. TPS evoked complex spiking when isoproterenol was present. However, complex spiking was not sufficient to enable TPS-induced LTP, which additionally required the inhibition of postsynaptic PP1. PP1 inhibition seems to promote the activation of Ca(2+)/calmodulin-dependent protein kinase (CaMKII), because (1) a CaMKII inhibitor blocked the induction of LTP by TPS paired with either isoproterenol or activated inhibitor-1 and (2) CaMKII in area CA1 was activated by the combination of TPS and 8-Br-cAMP but not by either stimulus alone. These results indicate that the cAMP pathway enables TPS-induced LTP by inhibiting PP1, thereby enhancing Ca(2+)-independent CaMKII activity.
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Affiliation(s)
- G P Brown
- Departments of Pharmacology and Psychiatry, Mount Sinai School of Medicine, New York, New York 10029, USA
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30
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Blitzer RD, Wong T, Giovannini MG, Pangalos MN, Robakis NK, Landau EM. Amyloid beta peptides activate the phosphoinositide signaling pathway in oocytes expressing rat brain RNA. Brain Res Mol Brain Res 2000; 76:115-20. [PMID: 10719221 DOI: 10.1016/s0169-328x(99)00340-x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Amyloid beta peptides (Abetas) of 39-43 amino acids constitute the major protein component of the amyloid plaques found in Alzheimer's disease brain. The generation of Abetas is regulated by the phosphoinositide (PI) pathway, which commonly couples to transmitter receptors. This study reports evidence for the activation of the PI pathway by Abetas in Xenopus oocytes expressing rat brain RNA. The naturally occurring peptides Abeta1-40 and Abeta1-42 were both active, whereas the cytotoxic fragment Abeta25-35 and the reverse peptide Abeta40-1 did not stimulate the PI pathway. Abetas rapidly lost potency in solution, suggesting that they were active only in their non-aggregated form. The Abeta response was saturable and not reduced by a substance P antagonist. This pharmacology excludes the participation of known Abeta binding proteins. The results indicate that a PI coupled receptor for non-aggregated Abeta may be present in brain.
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Affiliation(s)
- R D Blitzer
- Department of Psychiatry, Mount Sinai School of Medicine, New York, NY 10029, USA.
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31
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Abstract
Long-term potentiation (LTP) at the Schaffer collateral-CA1 synapse involves interacting signaling components, including calcium (Ca2+)/calmodulin-dependent protein kinase II (CaMKII) and cyclic adenosine monophosphate (cAMP) pathways. Postsynaptic injection of thiophosphorylated inhibitor-1 protein, a specific inhibitor of protein phosphatase-1 (PP1), substituted for cAMP pathway activation in LTP. Stimulation that induced LTP triggered cAMP-dependent phosphorylation of endogenous inhibitor-1 and a decrease in PP1 activity. This stimulation also increased phosphorylation of CaMKII at Thr286 and Ca2+-independent CaMKII activity in a cAMP-dependent manner. The blockade of LTP by a CaMKII inhibitor was not overcome by thiophosphorylated inhibitor-1. Thus, the cAMP pathway uses PP1 to gate CaMKII signaling in LTP.
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Affiliation(s)
- R D Blitzer
- Bronx VA Medical Center and Department of Psychiatry, Mount Sinai School of Medicine, New York, NY 10029, USA.
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32
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Nouranifar R, Blitzer RD, Wong T, Landau E. Metabotropic glutamate receptors limit adenylyl cyclase-mediated effects in rat hippocampus via protein kinase C. Neurosci Lett 1998; 244:101-5. [PMID: 9572595 DOI: 10.1016/s0304-3940(98)00131-1] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [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: 02/07/2023]
Abstract
Glutamate receptors of the metabotropic type (mGluRs) activate protein kinase C in hippocampus, but few physiological functions of this pathway are known. The present data show that mGluRs utilize protein kinase C to inhibit another second messenger system, the adenylyl cyclase pathway, in neurons of the CA1 area of hippocampus. Activation of mGluRs prevented beta-adrenergic receptors, which couple to adenylyl cyclase, from blocking the slow Ca2+-dependent afterhyperpolarization (AHP). Since the afterhyperpolarization modulates neuronal responsiveness, crosstalk between protein kinase C and the adenylyl cyclase pathway is likely to have physiological consequences. Moreover, mGluRs themselves block the afterhyperpolarization, so the observed interference with the beta-adrenergic response constitutes a hierarchical relationship in which mGluRs are dominant over beta-adrenergic receptors.
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Affiliation(s)
- R Nouranifar
- Psychiatry Service, Bronx Veterans Administration Medical Center, NY 10468, USA
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33
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Klein JT, Davis L, Olsen GE, Wong GS, Huger FP, Smith CP, Petko WW, Cornfeldt M, Wilker JC, Blitzer RD, Landau E, Haroutunian V, Martin LL, Effland RC. Synthesis and structure-activity relationships of N-propyl-N-(4-pyridinyl)-1H-indol-1-amine (besipirdine) and related analogs as potential therapeutic agents for Alzheimer's disease. J Med Chem 1996; 39:570-81. [PMID: 8558529 DOI: 10.1021/jm9506433] [Citation(s) in RCA: 44] [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] [Indexed: 01/31/2023]
Abstract
A series of novel N-(4-pyridinyl)-1H-indol-1-amines and other heteroaryl analogs was synthesized and evaluated in tests to determine potential utility for the treatment of Alzheimer's disease. From these compounds, N-propyl-N-(4-pyridinyl)-1H-indol-1-amine (besipirdine, 4c) was selected for clinical development based on in-depth biological evaluation. In addition to cholinomimetic properties based initially on in vitro inhibition of [3H]quinuclidinyl benzilate binding, in vivo reversal of scopolamine-induced behavioral deficits, and subsequently on other results, 4c also displayed enhancement of adrenergic mechanisms as evidenced in vitro by inhibition of [3H] clonidine binding and synaptosomal biogenic amine uptake, and in vivo by reversal of tetrabenazine-induced ptosis. The synthesis, structure-activity relationships for this series, and the biological profile of 4c are reported.
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Affiliation(s)
- J T Klein
- Hoechst-Roussel Pharmaceuticals Inc., Somerville, New Jersey 08876, USA
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34
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Abstract
The role of the cAMP pathway in LTP was studied in the CA1 region of hippocampus. Widely spaced trains of high frequency stimulation generated cAMP postsynaptically via NMDA receptors and calmodulin, consistent with the Ca2+/calmodulin-mediated stimulation of postsynaptic adenylyl cyclase. The early phase of LTP produced by the same pattern of high frequency stimulation was dependent on postsynaptic cAMP. However, synaptic transmission was not increased by postsynaptic application of cAMP. Early LTP became cAMP-independent when protein phosphatase inhibitors were injected postsynaptically. These observations indicate that in early LTP the cAMP signaling pathway, instead of transmitting signals for the generation of LTP, gates LTP through postsynaptic protein phosphatases.
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Affiliation(s)
- R D Blitzer
- Department of Psychiatry, Mount Sinai School of Medicine, New York, New York 10029, USA
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35
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Blitzer RD, Wong T, Nouranifar R, Landau EM. The cholinergic inhibition of afterhyperpolarization in rat hippocampus is independent of cAMP-dependent protein kinase. Brain Res 1994; 646:312-4. [PMID: 8069680 DOI: 10.1016/0006-8993(94)90096-5] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.4] [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: 01/28/2023]
Abstract
The possible involvement of protein kinase A (PKA) in the muscarinic inhibition of the slow afterhyperpolarizing current (IAHP) was investigated in rat hippocampal pyramidal cells. IAHP was recorded using the whole cell method in hippocampal slices, and Rp-cAMPS, a PKA antagonist, was applied intracellularly. The inhibition of IAHP by carbachol was not affected by Rp-cAMPS. In contrast, Rp-cAMPS reduced the cAMP-dependent inhibition of IAHP by norepinephrine. The results show that phosphorylation by PKA does not contribute to the muscarinic effect on IAHP.
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Affiliation(s)
- R D Blitzer
- Department of Psychiatry, Mount Sinai Medical Center, New York, NY 10029
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36
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Affiliation(s)
- E M Landau
- Department of Psychiatry, Bronx Veterans Administration Medical Center, New York, New York
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37
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Affiliation(s)
- R D Blitzer
- Department of Psychiatry, Bronx Veterans Administrations Medical Center, New York
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38
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Ma HW, Blitzer RD, Healy EC, Premont RT, Landau EM, Iyengar R. Receptor-evoked Cl- current in Xenopus oocytes is mediated through a beta-type phospholipase C. Cloning of a new form of the enzyme. J Biol Chem 1993; 268:19915-8. [PMID: 8397190] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
Abstract
Xenopus oocytes exhibit a receptor-evoked Cl- current that is mediated through the activation of phospholipase C (PLC) and release of intracellular Ca2+. The identity of PLC(s) mediating this effect is unknown. We have cloned cDNAs encoding a new form of PLC-beta from a Xenopus oocyte cDNA library. The Xenopus PLC-beta has substantial (33-64%) homology with mammalian beta 1, beta 2, beta 3, and beta 4 phospholipase C and is closest to PLC-beta 3, with 64% identity and 80% similarity. Injection of antisense oligonucleotides to a specific region of Xenopus PLC-beta results in degradation of its mRNA and significantly reduces Cl- currents evoked by both endogenous angiotensin receptors and expressed mammalian alpha 1b-adrenergic receptors and M1-muscarinic receptors as compared to responses in sense oligonucleotide-injected oocytes. Inhibition of the M1-muscarinic response by antisense oligonucleotides was nonadditive with pertussis toxin inhibition. PLC antisense oligonucleotide-injected oocytes show Cl- current responses to IP3 that are indistinguishable from sense oligonucleotide-injected oocytes. Since the receptor responses are pertussis toxin-sensitive, we conclude that we have isolated a new form of PLC-beta involved in the pertussis toxin-sensitive receptor stimulation of the Ca2+ activated Cl- current in Xenopus oocytes.
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MESH Headings
- Amino Acid Sequence
- Animals
- Base Sequence
- Chloride Channels
- Chlorides/metabolism
- Cloning, Molecular
- Drosophila/enzymology
- Drosophila/genetics
- Female
- Gene Library
- Isoenzymes/biosynthesis
- Isoenzymes/genetics
- Isoenzymes/metabolism
- Mammals
- Membrane Proteins/drug effects
- Membrane Proteins/physiology
- Molecular Sequence Data
- Oligodeoxyribonucleotides
- Oligonucleotides, Antisense/pharmacology
- Oocytes/drug effects
- Oocytes/enzymology
- Oocytes/physiology
- Pertussis Toxin
- RNA, Messenger/metabolism
- Receptors, Adrenergic, alpha/biosynthesis
- Receptors, Adrenergic, alpha/physiology
- Receptors, Angiotensin/physiology
- Receptors, Muscarinic/biosynthesis
- Receptors, Muscarinic/physiology
- Type C Phospholipases/biosynthesis
- Type C Phospholipases/genetics
- Type C Phospholipases/metabolism
- Virulence Factors, Bordetella/pharmacology
- Xenopus
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Affiliation(s)
- H W Ma
- Department of Pharmacology, Mount Sinai School of Medicine, City University of New York, New York 10029
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39
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Blitzer RD, Omri G, De Vivo M, Carty DJ, Premont RT, Codina J, Birnbaumer L, Cotecchia S, Caron MG, Lefkowitz RJ. Coupling of the expressed alpha 1B-adrenergic receptor to the phospholipase C pathway in Xenopus oocytes. The role of Go. J Biol Chem 1993; 268:7532-7. [PMID: 8385110] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
Abstract
alpha 1B-Adrenergic receptor mRNA was injected into Xenopus oocytes, resulting in a norepinephrine-evoked Cl- current. The response was proportional to norepinephrine concentration, blocked by prazosin, and dependent on intracellular Ca2+ derived from inositol trisphosphate-sensitive stores. Oocytes treated with 2 micrograms/ml pertussis toxin showed a time-dependent decrease of the norepinephrine response, taking up to 72 h to show an 80% decrease. Overnight treatment with 10 micrograms/ml pertussis toxin also resulted in 80% reduction. Responses to two other cloned receptors (M1-muscarinic and serotonin-1c) expressed in oocytes were also reduced 50% or more by 72 h of pertussis toxin treatment. Pertussis toxin labeling of the cloned Xenopus alpha o-subunit translated in vitro showed that it was a significantly poorer substrate for pertussis toxin than the two mammalian alpha o-subunits expressed and assayed under identical conditions. This unexpected biochemical behavior of the Xenopus alpha o-subunit is in agreement with the rather unusual treatment conditions required to observe the effects of pertussis toxin on the receptor-evoked Cl- current in the oocyte. Injection of mammalian heterotrimeric G(o) but not Gi3 significantly enhanced the norepinephrine-evoked Cl- current in oocytes. Injection of mixtures of anti-sense oligonucleotides to the Xenopus alpha o-subunit reduced the norepinephrine-evoked Cl- current by 60% within 24 h, compared with oocytes injected with the oligonucleotides encoding sense sequences. These studies indicate that the expressed alpha 1B-adrenergic receptor, like the native muscarinic receptor, utilizes G(o) to couple to the phospholipase C-mediated Cl- current in Xenopus oocytes.
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Affiliation(s)
- R D Blitzer
- Department of Psychiatry, Mount Sinai School of Medicine, City University of New York, New York 10029
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40
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Abstract
The possibility that cholinergic stimulation might directly activate a receptor-operated Ca2+ channel was investigated in the CA1 region of guinea pig hippocampus using intracellular recording techniques. Two cholinergic responses were studied: (1) the plateau depolarization evoked by cholinergic stimulation in the presence of Ba2+; and (2) the Ca2(+)-dependent component of membrane depolarization. Both of these responses were blocked by 1-5 microM of nifedipine, a blocker of voltage-dependent L-type Ca2+ channels. In addition, the plateau response was mimicked by direct postsynaptic depolarization in the presence of Ba2+. We conclude that cholinergic stimulation does not directly activate a Ca2+ conductance in these neurons, but rather leads to the indirect activation of L channels which may be located both pre- and postsynaptically.
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Affiliation(s)
- R D Blitzer
- Psychiatry Service, Bronx V.A. Medical Center, NY 10468
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41
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Abstract
Acute ethanol ingestion impairs memory in humans at concentrations associated with mild intoxication. A possible neurophysiological correlate of this effect is the suppression by ethanol of long-tem potentiation (LTP), a persistent increase in synaptic efficiency which has been proposed as a substrate for memory. However, in previous studies ethanol has been shown to impair LTP only at very high concentrations, near the lethal level in humans. We now report that ethanol can significantly reduce LTP in rat hippocampus at concentrations as low as 5 mM, a level attainable following ingestion of a single alcoholic drink. We also demonstrate that the potency of ethanol in depressing LTP correlates well with its potency in inhibiting the response to N-methyl-D-aspartate, an agonist at the glutamate receptors implicated in LTP induction. The influence of low ethanol concentrations on LTP may contribute to the memory impairment associated with its use in humans.
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Affiliation(s)
- R D Blitzer
- Psychiatry Service, Bronx V.A. Medical Center, NY 10468
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42
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Abstract
The effect of the cholinergic agonist carbachol on a putative substrate for memory (long-term potentiation; LTP) was investigated in slices of rat hippocampus (CA1 region). Carbachol (5 microM) increased LTP when the presynaptic depression of the EPSP was controlled. The results indicate that carbachol enhances the effectiveness of the tetanus, probably through postsynaptic mechanisms. This effect may have implications for the role of acetylcholine in memory and the use of cholinergics in memory disorders.
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Affiliation(s)
- R D Blitzer
- Psychiatry Service, Bronx V.A. Medical Center, NY 10468
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43
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Abstract
The effects of ethanol were studied intracellularly in hippocampal pyramidal cells in vitro. Ethanol, 50-100 mM, produced a marked suppression of neuronal firing. This effect was blocked by treating the cell with cyclic 3', 5'-adenosine monophosphate (cAMP) or cadmium ions. Ethanol had no effect on the after-hyperpolarizing current. It is concluded that the ethanol-induced reduction of firing rate is due to a calcium-dependent process, and modulated by cAMP.
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Affiliation(s)
- D M Benson
- Department of Psychiatry, Bronx VA Medical Center, NY 10468
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44
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Abstract
The effects of carbachol (CCh), a cholinergic agonist, were compared in voltage-clamped hippocampal pyramidal neurons in vitro, obtained from normal and fimbria-fornix-lesioned rats. A substantial increase in sensitivity to the effects of CCh was seen in denervated neurons. The supersensitivity was demonstrated on both the inward leak current and the calcium-dependent potassium current, IAHP. These findings provide convincing evidence for cholinergic denervation supersensitivity in the hippocampus.
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Affiliation(s)
- D M Benson
- Department of Psychiatry and Pharmacology, Mt. Sinai School of Medicine, Bronx, NY
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45
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Abstract
1. The effects of carbachol on hippocampal pyramidal neurones were studied in tissue slices in vitro with intracellular microelectrodes, employing current clamp and voltage clamp methods. 2. The calcium-dependent potassium current, IAHP, and the voltage-dependent potassium current, IM, were both reversibly blocked by the application of carbachol (5-10 microM). 3. Carbachol (1-10 microM) induced a steady inward current under circumstances in which both IAHP and IM were inactive. This inward current was sometimes difficult to reverse upon carbachol wash-out, an effect possibly related to receptor desensitization. 4. The depolarizing effect of carbachol was reversed by 0.1 microM-atropine, and exhibited an apparent dissociation coefficient of 1.2 microM for carbachol and 18 nM for pirenzepine, indicating that it is mediated by activation of an M1 muscarinic receptor. 5. The depolarizing effect or inward current induced by carbachol was completely blocked by the potassium channel blockers caesium, tetraethylammonium and barium. 6. The slope of the current-voltage (I-V) plots in carbachol was reduced in the majority of cells, and crossed the control I-V plots at a negative membrane potential. The reversal potentials in carbachol shifted in a positive direction when bathing potassium concentration was increased. 7. In a number of cells, the I-V curves in carbachol were parallel to or converged positively with the control I-V curves. 8. The effects of carbachol were compared to those of serotonin, which increases a 'pure' potassium conductance. Serotonin (10 microM) produced an increase in the slope of the I-V curve, with a reversal potential sensitive to changes in bathing potassium concentration. The carbachol reversal potential values were negative to those of serotonin at 5 and 10 mM-potassium. The equilibrium potentials for carbachol and serotonin were equal at 25 mM-potassium. 9. The negative values of the reversal potential at 5 and 10 mM-potassium and the occurrence of non-crossing I-V characteristics in carbachol could be explained by postulating a second effect of carbachol: namely, a non-specific conductance increase in the dendrites. 10. It is concluded that carbachol depolarizes pyramidal cells in the hippocampus by blocking a voltage-insensitive potassium leak channel and does so by activating M1 muscarinic receptors. In addition, carbachol may also activate a second conductance in the dendrites, which could account for the anomalous I-V characteristics sometimes seen in response to carbachol in these cells.
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Affiliation(s)
- D M Benson
- Department of Psychiatry, Mt Sinai School of Medicine, Bronx, NY
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46
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Abstract
Total RNA was extracted from 15-day-old whole rat brains. Microinjection of the RNA into Xenopus laevis oocytes induced electrophysiological responsiveness to cholecystokinin-8 (CCK) and bombesin (BBS) but not to corticotropin-releasing factor (CRF) or somatostatin. The responses to CCK and BBS were similar in shape, time course, and reversal potential to that induced by receptor mediated phospholipid breakdown and that which is induced by intracellular injection of IP3. These responses were not blocked by atropine or by mianserin, did not require extracellular Ca2+ and were completely suppressed by intracellular injection of EGTA.
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Affiliation(s)
- T M Moriarty
- Department of Psychiatry, Mount Sinai School of Medicine, New York, NY 10029
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47
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Abstract
Using a two-lever operant task rats were trained to discriminate 40 mg/kg IP of bupropion from saline. Despite bupropion's established dopaminergic activity in vitro and in vivo, it was found that the bupropion cue was neither mimicked by the dopaminergic drugs L-DOPA and bromocriptine nor blocked by a variety of neuroleptics (haloperidol, thioridazine, and thiothixene). In addition, bupropion was active in attenuating the behavior-suppressing effects of haloperidol, unlike amphetamine and the atypical antidepressants, nomifensine and viloxazine. The bupropion cue was not mimicked or disrupted by adrenergic or serotonergic drugs, but it did generalize to some stimulants (amphetamine, cocaine and caffeine) as well as to nomifensine and viloxazine. The generalizations were blocked by neuroleptics. These data indicate that bupropion's cue properties may not be based on its ability to modulate dopaminergic receptor activity. The possible involvement of phenylethylamine in the bupropion cue is also discussed.
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