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Seyedhosseini Tamijani SM, Beirami E, Ghazvini H, Rafaiee R, Nazeri M, Razavinasab M. A Review on the Disruption of Novel Object Recognition Induced by Methamphetamine. ADDICTION & HEALTH 2023; 15:289-297. [PMID: 38322487 PMCID: PMC10843358 DOI: 10.34172/ahj.2023.1307] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/21/2021] [Accepted: 11/07/2021] [Indexed: 02/08/2024]
Abstract
Background Methamphetamine (MA), is a widely abused synthetic psychostimulant that leads to irreversible brain damage manifested as cognitive impairments in humans and animals. The novel object recognition (NOR) task is a commonly used behavioral assay for the investigation of non-spatial memory in rodents. This test is based on the natural tendency of rodents to spend more time exploring a novel object than a familiar one. NOR test has been used in many studies investigating cognitive deficits caused by MA in rodents. The objective of the present study was to review neurobiological mechanisms that might be responsible for MA-induced NOR alterations. Methods A PubMed search showed 83 publications using novel object recognition and methamphetamine as keywords in the past 10 years. Findings The present study revealed different MA regimens cause recognition memory impairment in rodents. In addition, it was found that the main neurobiological mechanism involved in MA-induced recognition deficits is the dysfunction of monoaminergic systems. Conclusion NOR is a useful test to assess the cognitive functions following MA administration and evaluate the efficacy of new therapeutic agents in MA-addicted individuals.
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Affiliation(s)
| | - Elmira Beirami
- Department of Animal Biology, Faculty of Biological Sciences, Kharazmi University, Tehran, Iran
| | - Hamed Ghazvini
- Department of Neuroscience, School of Advanced Technologies in Medicine, Mazandaran University of Medical Sciences, Sari, Iran
| | - Raheleh Rafaiee
- Department of Neuroscience, School of Advanced Technologies in Medicine, Mazandaran University of Medical Sciences, Sari, Iran
| | - Masoud Nazeri
- Neuroscience Research Center, Neuropharmacology Institute, Kerman University of Medical Sciences, Kerman, Iran
| | - Moazamehosadat Razavinasab
- Neuroscience Research Center, Neuropharmacology Institute, Kerman University of Medical Sciences, Kerman, Iran
- Department of Physiology, Kerman University of Medical Sciences, Kerman, Iran
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2
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Gurung P, Shrestha R, Lim J, Thapa Magar TB, Kim HH, Kim YW. Euonymus alatus Twig Extract Protects against Scopolamine-Induced Changes in Brain and Brain-Derived Cells via Cholinergic and BDNF Pathways. Nutrients 2022; 15:nu15010128. [PMID: 36615789 PMCID: PMC9823662 DOI: 10.3390/nu15010128] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2022] [Revised: 12/20/2022] [Accepted: 12/22/2022] [Indexed: 12/29/2022] Open
Abstract
In the current study, the therapeutic and preventive effects of Euonymus alatus (EA) twig extract were investigated in a mouse model of cognitive deficit and B35 cells. Twig extract 1 was extracted with 70% ethanol and later twig extract 2 was extracted through liquid-liquid extraction with 70% ethanol and hexane. EA twig 2 (300 mg/kg) along with the standard drug donepezil (5 mg/kg) were orally administered to the mice for 34 days. Scopolamine was given intraperitoneally for 7 days. Administration of EA twig extract 2 significantly improved the passive avoidance test (PAT) in mice. EA twigs extract also restored the scopolamine-reduced brain-derived neurotrophic factor (BDNF)/extracellular regulated kinase (ERK)/cyclic AMP responsive element binding protein (CREB) signaling in B35 cells and the mouse hippocampus. In addition, EA twig extract significantly inhibited the acetylcholine esterase (AChE) activity in B35 cells in a dose-dependent manner. Chromatography and ESI MS analysis of EA twig extract revealed the presence of flavonoids; epicatechin, taxifolin, aromadendrin, and naringenin with catechin being the most abundant. These flavonoids exerted protective effects alone and had the possibility of synergistic effects in combination. Our work unmasks the ameliorating effect of EA twig extract 2 on scopolamine-associated cognitive impairments through the restoration of cholinergic systems and the BDNF/ERK/CREB pathway.
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Affiliation(s)
- Pallavi Gurung
- Dongsung Cancer Center, Dongsung Biopharmaceutical, Daegu 41061, Republic of Korea
| | - Rajeev Shrestha
- Dongsung Cancer Center, Dongsung Biopharmaceutical, Daegu 41061, Republic of Korea
| | - Junmo Lim
- Dongsung Cancer Center, Dongsung Biopharmaceutical, Daegu 41061, Republic of Korea
| | | | - Han-Hyuk Kim
- Medical Convergence Textile Center, Gyeongbuk Technopark, Gyeongsan 38412, Republic of Korea
| | - Yong-Wan Kim
- Dongsung Cancer Center, Dongsung Biopharmaceutical, Daegu 41061, Republic of Korea
- Correspondence:
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3
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Slater C, Liu Y, Weiss E, Yu K, Wang Q. The Neuromodulatory Role of the Noradrenergic and Cholinergic Systems and Their Interplay in Cognitive Functions: A Focused Review. Brain Sci 2022; 12:890. [PMID: 35884697 PMCID: PMC9320657 DOI: 10.3390/brainsci12070890] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2022] [Revised: 06/28/2022] [Accepted: 06/30/2022] [Indexed: 12/15/2022] Open
Abstract
The noradrenergic and cholinergic modulation of functionally distinct regions of the brain has become one of the primary organizational principles behind understanding the contribution of each system to the diversity of neural computation in the central nervous system. Decades of work has shown that a diverse family of receptors, stratified across different brain regions, and circuit-specific afferent and efferent projections play a critical role in helping such widespread neuromodulatory systems obtain substantial heterogeneity in neural information processing. This review briefly discusses the anatomical layout of both the noradrenergic and cholinergic systems, as well as the types and distributions of relevant receptors for each system. Previous work characterizing the direct and indirect interaction between these two systems is discussed, especially in the context of higher order cognitive functions such as attention, learning, and the decision-making process. Though a substantial amount of work has been done to characterize the role of each neuromodulator, a cohesive understanding of the region-specific cooperation of these two systems is not yet fully realized. For the field to progress, new experiments will need to be conducted that capitalize on the modular subdivisions of the brain and systematically explore the role of norepinephrine and acetylcholine in each of these subunits and across the full range of receptors expressed in different cell types in these regions.
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Affiliation(s)
- Cody Slater
- Department of Biomedical Engineering, Columbia University, ET 351, 500 W. 120th Street, New York, NY 10027, USA; (C.S.); (Y.L.); (E.W.); (K.Y.)
- Vagelos College of Physicians and Surgeons, Columbia University, 630 West 168th Street, New York, NY 10032, USA
| | - Yuxiang Liu
- Department of Biomedical Engineering, Columbia University, ET 351, 500 W. 120th Street, New York, NY 10027, USA; (C.S.); (Y.L.); (E.W.); (K.Y.)
| | - Evan Weiss
- Department of Biomedical Engineering, Columbia University, ET 351, 500 W. 120th Street, New York, NY 10027, USA; (C.S.); (Y.L.); (E.W.); (K.Y.)
| | - Kunpeng Yu
- Department of Biomedical Engineering, Columbia University, ET 351, 500 W. 120th Street, New York, NY 10027, USA; (C.S.); (Y.L.); (E.W.); (K.Y.)
| | - Qi Wang
- Department of Biomedical Engineering, Columbia University, ET 351, 500 W. 120th Street, New York, NY 10027, USA; (C.S.); (Y.L.); (E.W.); (K.Y.)
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Changes in cortical gene expression in the muscarinic M1 receptor knockout mouse: potential relevance to schizophrenia, Alzheimer's disease and cognition. NPJ SCHIZOPHRENIA 2021; 7:44. [PMID: 34521861 PMCID: PMC8440523 DOI: 10.1038/s41537-021-00174-z] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/03/2021] [Accepted: 07/14/2021] [Indexed: 11/08/2022]
Abstract
Postmortem and neuroimaging studies show low levels of cortical muscarinic M1 receptors (CHRM1) in patients with schizophrenia which is significant because CHRM signalling has been shown to change levels of gene expression and cortical gene expression is altered in schizophrenia. We decided to identify CHRM1-mediated changes in cortical gene expression by measuring levels of RNA in the cortex of the Chrm1-/- mouse (n = 10), where there would be no signalling by that receptor, and in wild type mouse (n = 10) using the Affymetrix Mouse Exon 1.0 ST Array. We detected RNA for 15,501 annotated genes and noncoding RNA of which 1,467 RNAs were higher and 229 RNAs lower in the cortex of the Chrm1-/- mouse. Pathways and proteins affected by the changes in cortical gene expression in the Chrm1-/- are linked to the molecular pathology of schizophrenia. Our human cortical gene expression data showed 47 genes had altered expression in Chrm1-/- mouse and the frontal pole from patients with schizophrenia with the change in expression of 44 genes being in opposite directions. In addition, genes with altered levels of expression in the Chrm1-/- mouse have been shown to affect amyloid precursor protein processing which is associated with the pathophysiology of Alzheimer's disease, and 69 genes with altered expression in the Chrm1-/- mouse are risk genes associated with human cognitive ability. Our findings argue CHRM1-mediated changes in gene expression are relevant to the pathophysiologies of schizophrenia and Alzheimer's disease and the maintenance of cognitive ability in humans.
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van der Westhuizen ET, Choy KHC, Valant C, McKenzie-Nickson S, Bradley SJ, Tobin AB, Sexton PM, Christopoulos A. Fine Tuning Muscarinic Acetylcholine Receptor Signaling Through Allostery and Bias. Front Pharmacol 2021; 11:606656. [PMID: 33584282 PMCID: PMC7878563 DOI: 10.3389/fphar.2020.606656] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2020] [Accepted: 11/30/2020] [Indexed: 12/18/2022] Open
Abstract
The M1 and M4 muscarinic acetylcholine receptors (mAChRs) are highly pursued drug targets for neurological diseases, in particular for Alzheimer's disease and schizophrenia. Due to high sequence homology, selective targeting of any of the M1-M5 mAChRs through the endogenous ligand binding site has been notoriously difficult to achieve. With the discovery of highly subtype selective mAChR positive allosteric modulators in the new millennium, selectivity through targeting an allosteric binding site has opened new avenues for drug discovery programs. However, some hurdles remain to be overcome for these promising new drug candidates to progress into the clinic. One challenge is the potential for on-target side effects, such as for the M1 mAChR where over-activation of the receptor by orthosteric or allosteric ligands can be detrimental. Therefore, in addition to receptor subtype selectivity, a drug candidate may need to exhibit a biased signaling profile to avoid such on-target adverse effects. Indeed, recent studies in mice suggest that allosteric modulators for the M1 mAChR that bias signaling toward specific pathways may be therapeutically important. This review brings together details on the signaling pathways activated by the M1 and M4 mAChRs, evidence of biased agonism at these receptors, and highlights pathways that may be important for developing new subtype selective allosteric ligands to achieve therapeutic benefit.
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Affiliation(s)
- Emma T. van der Westhuizen
- Drug Discovery Biology, Monash Institute for Pharmaceutical Research, Monash University, Parkville, VIC, Australia
| | - K. H. Christopher Choy
- Drug Discovery Biology, Monash Institute for Pharmaceutical Research, Monash University, Parkville, VIC, Australia
| | - Celine Valant
- Drug Discovery Biology, Monash Institute for Pharmaceutical Research, Monash University, Parkville, VIC, Australia
| | - Simon McKenzie-Nickson
- Drug Discovery Biology, Monash Institute for Pharmaceutical Research, Monash University, Parkville, VIC, Australia
| | - Sophie J. Bradley
- Centre for Translational Pharmacology, Institute of Molecular Cell and Systems Biology, University of Glasgow, Glasgow, United Kingdom
| | - Andrew B. Tobin
- Centre for Translational Pharmacology, Institute of Molecular Cell and Systems Biology, University of Glasgow, Glasgow, United Kingdom
| | - Patrick M. Sexton
- Drug Discovery Biology, Monash Institute for Pharmaceutical Research, Monash University, Parkville, VIC, Australia
| | - Arthur Christopoulos
- Drug Discovery Biology, Monash Institute for Pharmaceutical Research, Monash University, Parkville, VIC, Australia
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Wattanathorn J, Palachai N, Thukham-mee W, Muchimapura S. Memory-Enhancing Effect of a Phytosome Containing the Combined Extract of Mulberry Fruit and Ginger in an Animal Model of Ischemic Stroke with Metabolic Syndrome. OXIDATIVE MEDICINE AND CELLULAR LONGEVITY 2020; 2020:3096826. [PMID: 32802263 PMCID: PMC7411500 DOI: 10.1155/2020/3096826] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/14/2020] [Revised: 06/04/2020] [Accepted: 06/26/2020] [Indexed: 12/27/2022]
Abstract
The prevalence of dementia following cerebral ischemia in metabolic syndrome (MetS) condition is increasing, and most of the cases are often severe. Unfortunately, no effective strategy for treating this condition is available. Based on the positive modulation effect of a polyphenol-rich substance on dementia and the improvement in bioavailability and stability of polyphenols induced by the phytosome technique together with the use of the synergistic concept, we hypothesized that a phytosome containing the combined extract of mulberry fruit and ginger (PMG) should mitigate dementia and memory impairment following ischemic stroke in MetS. MetS was induced in male Wistar rats weighing 180-200 g by exposure to a 16-week feeding period of high-carbohydrate high-fat (HCHF) diet. MetS rats were orally given PMG at doses of 50, 100, and 200 mg·kg-1 BW 21 days before and 21 days after the occlusion of the right middle cerebral artery (Rt. MCAO). Then, their spatial memory was determined and the possible underlying mechanisms explored via the alterations of acetylcholinesterase (AChE), neuron density, malondialdehyde (MDA), superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GSH-Px), interleukin-6 (IL-6), and signal transduction via extracellular signal-regulated kinase (ERK) pathway in both the cerebral cortex and the hippocampus. It was found that PMG significantly enhanced memory. It also decreased AChE, IL-6, and MDA but increased SOD, CAT, GSH-Px, neuron density, and phosphorylation of ERK. These data suggested the cognitive enhancing effect of PMG. The possible underlying mechanisms might occur partly via the improvement of cholinergic function via the ERK pathway together with the decrease in neurodegeneration induced by the reduction of oxidative stress and inflammation. However, a subchronic toxicity study is also required to assure the safety of PMG consumption before moving forward to a clinical trial study.
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Affiliation(s)
- Jintanaporn Wattanathorn
- Department of Physiology, Faculty of Medicine, Khon Kaen University, Khon Kaen, Thailand 40002
- Integrative Complementary Alternative Medicine Research, Khon Kaen University, Khon Kaen, Thailand 40002
- Research Institute for Human High Performance and Health Promotion, Khon Kaen University, Khon Kaen, Thailand 40002
| | - Nut Palachai
- Integrative Complementary Alternative Medicine Research, Khon Kaen University, Khon Kaen, Thailand 40002
- Research Institute for Human High Performance and Health Promotion, Khon Kaen University, Khon Kaen, Thailand 40002
- Department of Physiology and Graduate School (Neuroscience Program), Faculty of Medicine, Khon Kaen University, Khon Kaen, Thailand 40002
| | - Wipawee Thukham-mee
- Department of Physiology, Faculty of Medicine, Khon Kaen University, Khon Kaen, Thailand 40002
- Integrative Complementary Alternative Medicine Research, Khon Kaen University, Khon Kaen, Thailand 40002
- Research Institute for Human High Performance and Health Promotion, Khon Kaen University, Khon Kaen, Thailand 40002
| | - Supaporn Muchimapura
- Department of Physiology, Faculty of Medicine, Khon Kaen University, Khon Kaen, Thailand 40002
- Integrative Complementary Alternative Medicine Research, Khon Kaen University, Khon Kaen, Thailand 40002
- Research Institute for Human High Performance and Health Promotion, Khon Kaen University, Khon Kaen, Thailand 40002
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Durkee CA, Covelo A, Lines J, Kofuji P, Aguilar J, Araque A. G i/o protein-coupled receptors inhibit neurons but activate astrocytes and stimulate gliotransmission. Glia 2019; 67:1076-1093. [PMID: 30801845 DOI: 10.1002/glia.23589] [Citation(s) in RCA: 125] [Impact Index Per Article: 25.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2018] [Revised: 12/06/2018] [Accepted: 12/26/2018] [Indexed: 12/31/2022]
Abstract
G protein-coupled receptors (GPCRs) play key roles in intercellular signaling in the brain. Their effects on cellular function have been largely studied in neurons, but their functional consequences on astrocytes are less known. Using both endogenous and chemogenetic approaches with DREADDs, we have investigated the effects of Gq and Gi/o GPCR activation on astroglial Ca2+ -based activity, gliotransmitter release, and the functional consequences on neuronal electrical activity. We found that while Gq GPCR activation led to cellular activation in both neurons and astrocytes, Gi/o GPCR activation led to cellular inhibition in neurons and cellular activation in astrocytes. Astroglial activation by either Gq or Gi/o protein-mediated signaling stimulated gliotransmitter release, which increased neuronal excitability. Additionally, activation of Gq and Gi/o DREADDs in vivo increased astrocyte Ca2+ activity and modified neuronal network electrical activity. Present results reveal additional complexity of the signaling consequences of excitatory and inhibitory neurotransmitters in astroglia-neuron network operation and brain function.
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Affiliation(s)
- Caitlin A Durkee
- Department of Neuroscience, University of Minnesota, Minneapolis, Minnesota
| | - Ana Covelo
- Department of Neuroscience, University of Minnesota, Minneapolis, Minnesota
| | - Justin Lines
- Department of Neuroscience, University of Minnesota, Minneapolis, Minnesota
| | - Paulo Kofuji
- Department of Neuroscience, University of Minnesota, Minneapolis, Minnesota
| | - Juan Aguilar
- Laboratory of Experimental Neurophysiology, Hospital Nacional de Parapléjicos, Toledo, Spain
| | - Alfonso Araque
- Department of Neuroscience, University of Minnesota, Minneapolis, Minnesota
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Nguyen BT, Sharma N, Shin EJ, Jeong JH, Lee SH, Jang CG, Nah SY, Nabeshima T, Yoneda Y, Kim HC. Theanine attenuates memory impairments induced by klotho gene depletion in mice. Food Funct 2019; 10:325-332. [DOI: 10.1039/c8fo01577e] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Theanine (γ-glutamylethylamide), an amino acid in tea, is a putative neuroprotective and antioxidant compound capable of improving lifespan and cognitive function.
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9
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Sabbir MG, Fernyhough P. Muscarinic receptor antagonists activate ERK-CREB signaling to augment neurite outgrowth of adult sensory neurons. Neuropharmacology 2018; 143:268-281. [PMID: 30248305 DOI: 10.1016/j.neuropharm.2018.09.020] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2018] [Revised: 08/09/2018] [Accepted: 09/12/2018] [Indexed: 01/09/2023]
Abstract
A major cellular effector activated by G protein coupled receptors is extracellular signal-regulated kinase (ERK). The ERK signaling cascade regulates a variety of cellular processes including growth and proliferation. Both G protein and β-arrestin-mediated signaling lead to ERK activation by phosphorylation through different kinases. Recently, we have shown muscarinic acetylcholine type 1 receptor (M1R) antagonists, muscarinic toxin 7 (MT7) and pirenzepine, elevated neurite outgrowth and protected from small and large fiber neuropathy in adult sensory neurons in various animal models. Thus, we tested the novel hypothesis that muscarinic antagonists could drive neurite outgrowth through altered M1R-ERK signaling. We have used two dimensional isoelectric focusing/SDS-PAGE combined with analysis using multiple phospho-epitope specific antibodies to study ERK1/2 phosphorylation and activation of its downstream nuclear effector cyclic response element binding protein (CREB). Activated CREB is known to exhibit neuroprotective and growth promoting effects. One hour of treatment with MT7 and pirenzepine activated ERK through M1R and induced a significant increase in levels of pCREB(S133) in cultured sensory neurons. Further, pharmacological blockade or siRNA based knockdown of ERK abolished the MT7 and pirenzepine mediated neuritogenic effect. In addition, we have shown drug-induced alterations of charged protein fractions that may possess additional post-translationally modified forms of ERK and CREB. For the first time we show that long-term treatment, e.g. 1 h, with muscarinic antagonists selective or specific for M1R can activate a biased β-arrestin dependent ERK-CREB signal cascade. Our study gives novel insight into muscarinic antagonist-mediated modulation of M1R-ERK-CREB signaling which could be exploited for therapy in neuropathic diseases.
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Affiliation(s)
- Mohammad Golam Sabbir
- Division of Neurodegenerative Disorders, St. Boniface Hospital Albrechtsen Research Centre, Winnipeg, MB, R2H 2A6, Canada.
| | - Paul Fernyhough
- Division of Neurodegenerative Disorders, St. Boniface Hospital Albrechtsen Research Centre, Winnipeg, MB, R2H 2A6, Canada; Dept of Pharmacology & Therapeutics, University of Manitoba, MB, R3T 2N2, Canada.
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10
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Yohn SE, Conn PJ. Positive allosteric modulation of M 1 and M 4 muscarinic receptors as potential therapeutic treatments for schizophrenia. Neuropharmacology 2018; 136:438-448. [PMID: 28893562 PMCID: PMC5844786 DOI: 10.1016/j.neuropharm.2017.09.012] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2017] [Revised: 09/06/2017] [Accepted: 09/08/2017] [Indexed: 01/22/2023]
Abstract
Current antipsychotic drugs provide symptomatic relief for positive symptoms of schizophrenia, but do not offer symptom management for negative and cognitive symptoms. In addition, many patients discontinue treatment due to adverse side effects. Therefore, there is a critical need to develop more effective and safe treatment options. Although the etiology of schizophrenia is unclear, considerable data from post-mortem, neuroimaging and neuropharmacology studies support a role of the muscarinic acetylcholine (mAChRs) in the pathophysiology of schizophrenia. Substantial evidence suggests that activation of mAChRs has the potential to treat all symptom domains of schizophrenia. Despite encouraging results in demonstrating efficacy, clinical trials of nonselective mAChR agonists were limited in their clinical utility due to dose-limiting peripheral side effects. Accordingly, efforts have been made to specifically target centrally located M1 and M4 mAChR subtypes devoid of adverse-effect liability. To circumvent this limitation, there have been tremendous advances in the discovery of ligands that bind at allosteric sites, binding sites distinct from the orthosteric site, which are structurally less conserved and thereby afford high levels of receptor subtype selectivity. The discovery of subtype-specific allosteric modulators has greatly advanced our understanding of the physiological role of various muscarinic receptor subtypes in schizophrenia and the potential utility of M1 and M4 mAChR subtypes as targets for the development of novel treatments for schizophrenia and related disorders. This article is part of the Special Issue entitled 'Neuropharmacology on Muscarinic Receptors'.
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Affiliation(s)
- Samantha E Yohn
- Department of Pharmacology, Vanderbilt University, Nashville, TN 37232, United States; Vanderbilt Center for Neuroscience Drug Discovery, Vanderbilt University, Nashville, TN 37232, United States
| | - P Jeffrey Conn
- Department of Pharmacology, Vanderbilt University, Nashville, TN 37232, United States; Vanderbilt Center for Neuroscience Drug Discovery, Vanderbilt University, Nashville, TN 37232, United States.
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Sabbir MG, Calcutt NA, Fernyhough P. Muscarinic Acetylcholine Type 1 Receptor Activity Constrains Neurite Outgrowth by Inhibiting Microtubule Polymerization and Mitochondrial Trafficking in Adult Sensory Neurons. Front Neurosci 2018; 12:402. [PMID: 29997469 PMCID: PMC6029366 DOI: 10.3389/fnins.2018.00402] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2018] [Accepted: 05/24/2018] [Indexed: 11/13/2022] Open
Abstract
The muscarinic acetylcholine type 1 receptor (M1R) is a metabotropic G protein-coupled receptor. Knockout of M1R or exposure to selective or specific receptor antagonists elevates neurite outgrowth in adult sensory neurons and is therapeutic in diverse models of peripheral neuropathy. We tested the hypothesis that endogenous M1R activation constrained neurite outgrowth via a negative impact on the cytoskeleton and subsequent mitochondrial trafficking. We overexpressed M1R in primary cultures of adult rat sensory neurons and cell lines and studied the physiological and molecular consequences related to regulation of cytoskeletal/mitochondrial dynamics and neurite outgrowth. In adult primary neurons, overexpression of M1R caused disruption of the tubulin, but not actin, cytoskeleton and significantly reduced neurite outgrowth. Over-expression of a M1R-DREADD mutant comparatively increased neurite outgrowth suggesting that acetylcholine released from cultured neurons interacts with M1R to suppress neurite outgrowth. M1R-dependent constraint on neurite outgrowth was removed by selective (pirenzepine) or specific (muscarinic toxin 7) M1R antagonists. M1R-dependent disruption of the cytoskeleton also diminished mitochondrial abundance and trafficking in distal neurites, a disorder that was also rescued by pirenzepine or muscarinic toxin 7. M1R activation modulated cytoskeletal dynamics through activation of the G protein (Gα13) that inhibited tubulin polymerization and thus reduced neurite outgrowth. Our study provides a novel mechanism of M1R control of Gα13 protein-dependent modulation of the tubulin cytoskeleton, mitochondrial trafficking and neurite outgrowth in axons of adult sensory neurons. This novel pathway could be harnessed to treat dying-back neuropathies since anti-muscarinic drugs are currently utilized for other clinical conditions.
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Affiliation(s)
- Mohammad G Sabbir
- Division of Neurodegenerative Disorders, St. Boniface Hospital Research Centre, Winnipeg, MB, Canada
| | - Nigel A Calcutt
- Department of Pathology, University of California, San Diego, San Diego, CA, United States
| | - Paul Fernyhough
- Division of Neurodegenerative Disorders, St. Boniface Hospital Research Centre, Winnipeg, MB, Canada.,Department of Pharmacology and Therapeutics, University of Manitoba, Winnipeg, MB, Canada
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12
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Ruan Q, Yu Z, Zhang W, Ruan J, Liu C, Zhang R. Cholinergic Hypofunction in Presbycusis-Related Tinnitus With Cognitive Function Impairment: Emerging Hypotheses. Front Aging Neurosci 2018; 10:98. [PMID: 29681847 PMCID: PMC5897739 DOI: 10.3389/fnagi.2018.00098] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2017] [Accepted: 03/22/2018] [Indexed: 01/21/2023] Open
Abstract
Presbycusis (age-related hearing loss) is a potential risk factor for tinnitus and cognitive deterioration, which result in poor life quality. Presbycusis-related tinnitus with cognitive impairment is a common phenotype in the elderly population. In these individuals, the central auditory system shows similar pathophysiological alterations as those observed in Alzheimer's disease (AD), including cholinergic hypofunction, epileptiform-like network synchronization, chronic inflammation, and reduced GABAergic inhibition and neural plasticity. Observations from experimental rodent models indicate that recovery of cholinergic function can improve memory and other cognitive functions via acetylcholine-mediated GABAergic inhibition enhancement, nicotinic acetylcholine receptor (nAChR)-mediated anti-inflammation, glial activation inhibition and neurovascular protection. The loss of cholinergic innervation of various brain structures may provide a common link between tinnitus seen in presbycusis-related tinnitus and age-related cognitive impairment. We hypothesize a key component of the condition is the withdrawal of cholinergic input to a subtype of GABAergic inhibitory interneuron, neuropeptide Y (NPY) neurogliaform cells. Cholinergic denervation might not only cause the degeneration of NPY neurogliaform cells, but may also result in decreased AChR activation in GABAergic inhibitory interneurons. This, in turn, would lead to reduced GABA release and inhibitory regulation of neural networks. Reduced nAChR-mediated anti-inflammation due to the loss of nicotinic innervation might lead to the transformation of glial cells and release of inflammatory mediators, lowering the buffering of extracellular potassium and glutamate metabolism. Further research will provide evidence for the recovery of cholinergic function with the use of cholinergic input enhancement alone or in combination with other rehabilitative interventions to reestablish inhibitory regulation mechanisms of involved neural networks for presbycusis-related tinnitus with cognitive impairment.
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Affiliation(s)
- Qingwei Ruan
- Shanghai Institute of Geriatrics and Gerontology, Shanghai Key Laboratory of Clinical Geriatrics, Huadong Hospital, and Research Center of Aging and Medicine, Shanghai Medical College, Fudan University, Shanghai, China
| | - Zhuowei Yu
- Shanghai Institute of Geriatrics and Gerontology, Shanghai Key Laboratory of Clinical Geriatrics, Huadong Hospital, and Research Center of Aging and Medicine, Shanghai Medical College, Fudan University, Shanghai, China
| | - Weibin Zhang
- Shanghai Institute of Geriatrics and Gerontology, Shanghai Key Laboratory of Clinical Geriatrics, Huadong Hospital, and Research Center of Aging and Medicine, Shanghai Medical College, Fudan University, Shanghai, China
| | - Jian Ruan
- Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Chunhui Liu
- Department of Otolaryngology, Huadong Hospital, Shanghai Medical College, Fudan University, Shanghai, China
| | - Ruxin Zhang
- Department of Otolaryngology, Huadong Hospital, Shanghai Medical College, Fudan University, Shanghai, China
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Mai HN, Sharma N, Shin EJ, Nguyen BT, Nguyen PT, Jeong JH, Jang CG, Cho EH, Nah SY, Kim NH, Nabeshima T, Kim HC. Exposure to far-infrared rays attenuates methamphetamine-induced recognition memory impairment via modulation of the muscarinic M1 receptor, Nrf2, and PKC. Neurochem Int 2018; 116:63-76. [PMID: 29572053 DOI: 10.1016/j.neuint.2018.03.009] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2017] [Revised: 03/15/2018] [Accepted: 03/19/2018] [Indexed: 01/15/2023]
Abstract
We demonstrated that activation of protein kinase Cδ (PKCδ) and inactivation of the glutathione peroxidase-1 (GPx-1)-dependent systems are critical for methamphetamine (MA)-induced recognition memory impairment. We also demonstrated that exposure to far-infrared rays (FIR) causes induction of the glutathione (GSH)-dependent system, including induction of the GPx-1 gene. Here, we investigated whether exposure to FIR rays affects MA-induced recognition memory impairment and whether it modulates PKC, cholinergic receptors, and the GSH-dependent system. Because the PKC activator bryostatin-1 mainly induces PKCα, PKCε, and PKCδ, we assessed expression of these proteins after MA treatment. MA treatment selectively increased PKCδ expression and its phosphorylation. Exposure to FIR rays significantly attenuated MA-induced increases in PKCδ phosphorylation. Importantly, bryostatin-1 potentiated MA-induced phosphorylation of PKCδ. MA treatment significantly decreased M1, M3, and M4 muscarinic acetylcholine receptors (mAChRs) and β2 nicotinic acetylcholine receptor expression. Of these, the decrease was most pronounced in M1 mAChR. Exposure to FIR significantly attenuated MA-induced decreases in the M1 mAChR and phospho-ERK1/2, while it facilitated Nrf2-dependent GSH induction. Dicyclomine, an M1 mAChR antagonist, and l-buthionine-(S, R)-sulfoximine (BSO), an inhibitor of GSH synthesis, counteracted against the protective potentials mediated by FIR. More importantly, the memory-enhancing potential of FIR rays was significantly counteracted by bryostatin-1, dicyclomine, and BSO. Our results suggest that exposure to FIR rays attenuates MA-induced impairment in recognition memory via up-regulation of M1 mAChR, Nrf2-dependent GSH induction, and ERK1/2 phosphorylation by inhibiting PKCδ phosphorylation by bryostatin-1.
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Affiliation(s)
- Huynh Nhu Mai
- Neuropsychopharmacology and Toxicology Program, College of Pharmacy, Kangwon National University, Chunchon 24341, Republic of Korea
| | - Naveen Sharma
- Neuropsychopharmacology and Toxicology Program, College of Pharmacy, Kangwon National University, Chunchon 24341, Republic of Korea
| | - Eun-Joo Shin
- Neuropsychopharmacology and Toxicology Program, College of Pharmacy, Kangwon National University, Chunchon 24341, Republic of Korea
| | - Bao Trong Nguyen
- Neuropsychopharmacology and Toxicology Program, College of Pharmacy, Kangwon National University, Chunchon 24341, Republic of Korea
| | - Phuong Tram Nguyen
- Neuropsychopharmacology and Toxicology Program, College of Pharmacy, Kangwon National University, Chunchon 24341, Republic of Korea
| | - Ji Hoon Jeong
- Department of Pharmacology, College of Medicine, Chung-Ang University, Seoul 06974, Republic of Korea
| | - Choon-Gon Jang
- Department of Pharmacology, School of Pharmacy, Sungkyunkwan University, Suwon 16419, Republic of Korea
| | - Eun-Hee Cho
- Department of Internal Medicine, Medical School, Kangwon National University, Chunchon 24341, Republic of Korea
| | - Seung-Yeol Nah
- Ginsentology Research Laboratory and Department of Physiology, College of Veterinary Medicine and Bio/Molecular Informatics Center, KonKuk University, Seoul 05029, Republic of Korea
| | - Nam Hun Kim
- College of Forest and Environmental Sciences, Kangwon National University, Chunchon 24341, Republic of Korea.
| | - Toshitaka Nabeshima
- Advanced Diagnostic System Research Laboratory, Fujita Health University Graduate School of Health Sciences, Aichi 470-1192, Japan; Aino University, Ibaragi, 567-0012, Japan
| | - Hyoung-Chun Kim
- Neuropsychopharmacology and Toxicology Program, College of Pharmacy, Kangwon National University, Chunchon 24341, Republic of Korea.
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Pariyar R, Yoon CS, Svay T, Kim DS, Cho HK, Kim SY, Oh H, Kim YC, Kim J, Lee HS, Seo J. Vitis labruscana leaf extract ameliorates scopolamine-induced impairments with activation of Akt, ERK and CREB in mice. PHYTOMEDICINE : INTERNATIONAL JOURNAL OF PHYTOTHERAPY AND PHYTOPHARMACOLOGY 2017; 36:8-17. [PMID: 29157831 DOI: 10.1016/j.phymed.2017.09.008] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/22/2016] [Revised: 06/17/2017] [Accepted: 09/21/2017] [Indexed: 06/07/2023]
Abstract
BACKGROUND Grapes are among the most widely consumed plants and are used as a folk medicine. Vitis species have been traditionally used as anti-inflammatory, analgesic, and memory-enhancing agents, but, their biological activities of discarded grape leaves are not completely understood. PURPOSE We investigated the effects of alcoholic aqueous leaf extract of Vitis labruscana (LEVL) in a mouse model of memory impairment and tried to ascertain its mechanism. We also evaluated its effects in SH-SY5Y cells. METHODS LEVL (50, 100, and 150 mg/kg) was administered to ICR mice once daily for 7 days. Memory impairment was induced with intraperitoneal scopolamine injections (1 mg/kg) and measured with the Y-maze test and a passive avoidance task. LEVL-induced signaling was evaluated in SH-SY5Y cells and mouse hippocampi. RESULTS We first identified quercetin-3-O-glucuronide as LEVL's major component. We then showed that LEVL promoted phosphorylation of Akt, extracellular regulated kinase (ERK), and cyclic AMP response element binding protein (CREB) and proliferation of SH-SY5Y cells. Oral LEVL administration (100 mg/kg) for 7 days significantly reversed scopolamine-induced reductions of spontaneous alternation in the Y-maze test and scopolamine-induced shortening of latency times in the passive avoidance task's retention trial. Consistent with the cell experiment results, LEVL restored scopolamine-decreased phosphorylation of Akt, ERK, and CREB and scopolamine-reduced expression of brain-derived neuroprotective factor expression in mouse hippocampi. CONCLUSION Our results suggest that LEVL promotes phosphorylation of Akt, ERK, and CREB in the hippocampus and ameliorates scopolamine-induced memory impairment in mice.
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Affiliation(s)
- Ramesh Pariyar
- Institute of Pharmaceutical Research and Development, College of Pharmacy, Wonkwang University, Iksan 570-749, Republic of Korea; Hanbang Body-Fluid Research Center, Wonkwang University, Iksan 570-749, Republic of Korea
| | - Chi-Su Yoon
- Institute of Pharmaceutical Research and Development, College of Pharmacy, Wonkwang University, Iksan 570-749, Republic of Korea; Hanbang Body-Fluid Research Center, Wonkwang University, Iksan 570-749, Republic of Korea; Standardized Material Bank for New Botanical Drugs, College of Pharmacy, Wonkwang University, Iksan 570-749, Republic of Korea
| | - Thida Svay
- Institute of Pharmaceutical Research and Development, College of Pharmacy, Wonkwang University, Iksan 570-749, Republic of Korea; Hanbang Body-Fluid Research Center, Wonkwang University, Iksan 570-749, Republic of Korea
| | - Dae-Sung Kim
- Hanpoong Pharm & Foods Co., Ltd., Jeonju, 561-841, Republic of Korea
| | - Hyoung-Kwon Cho
- Hanpoong Pharm & Foods Co., Ltd., Jeonju, 561-841, Republic of Korea
| | - Sung Yeon Kim
- Institute of Pharmaceutical Research and Development, College of Pharmacy, Wonkwang University, Iksan 570-749, Republic of Korea
| | - Hyuncheol Oh
- Institute of Pharmaceutical Research and Development, College of Pharmacy, Wonkwang University, Iksan 570-749, Republic of Korea; Hanbang Body-Fluid Research Center, Wonkwang University, Iksan 570-749, Republic of Korea; Standardized Material Bank for New Botanical Drugs, College of Pharmacy, Wonkwang University, Iksan 570-749, Republic of Korea
| | - Youn-Chul Kim
- Institute of Pharmaceutical Research and Development, College of Pharmacy, Wonkwang University, Iksan 570-749, Republic of Korea; Hanbang Body-Fluid Research Center, Wonkwang University, Iksan 570-749, Republic of Korea; Standardized Material Bank for New Botanical Drugs, College of Pharmacy, Wonkwang University, Iksan 570-749, Republic of Korea
| | - Jaehyo Kim
- Hanbang Body-Fluid Research Center, Wonkwang University, Iksan 570-749, Republic of Korea; College of Oriental Medicine, Wonkwang Universit, Iksan 570-749, Republic of Korea
| | - Ho-Sub Lee
- Hanbang Body-Fluid Research Center, Wonkwang University, Iksan 570-749, Republic of Korea; College of Oriental Medicine, Wonkwang Universit, Iksan 570-749, Republic of Korea
| | - Jungwon Seo
- Institute of Pharmaceutical Research and Development, College of Pharmacy, Wonkwang University, Iksan 570-749, Republic of Korea; Hanbang Body-Fluid Research Center, Wonkwang University, Iksan 570-749, Republic of Korea.
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15
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Thomsen M, Sørensen G, Dencker D. Physiological roles of CNS muscarinic receptors gained from knockout mice. Neuropharmacology 2017; 136:411-420. [PMID: 28911965 DOI: 10.1016/j.neuropharm.2017.09.011] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2016] [Revised: 09/06/2017] [Accepted: 09/08/2017] [Indexed: 12/29/2022]
Abstract
Because the five muscarinic acetylcholine receptor subtypes have overlapping distributions in many CNS tissues, and because ligands with a high degree of selectivity for a given subtype long remained elusive, it has been difficult to determine the physiological functions of each receptor. Genetically engineered knockout mice, in which one or more muscarinic acetylcholine receptor subtype has been inactivated, have been instrumental in identifying muscarinic receptor functions in the CNS, at the neuronal, circuit, and behavioral level. These studies revealed important functions of muscarinic receptors modulating neuronal activity and neurotransmitter release in many brain regions, shaping neuronal plasticity, and affecting functions ranging from motor and sensory function to cognitive processes. As gene targeting technology evolves including the use of conditional, cell type specific strains, knockout mice are likely to continue to provide valuable insights into brain physiology and pathophysiology, and advance the development of new medications for a range of conditions such as Alzheimer's disease, Parkinson's disease, schizophrenia, and addictions, as well as non-opioid analgesics. This article is part of the Special Issue entitled 'Neuropharmacology on Muscarinic Receptors'.
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Affiliation(s)
- Morgane Thomsen
- Laboratory of Neuropsychiatry, Psychiatric Center Copenhagen and University of Copenhagen, Denmark; Alcohol and Drug Abuse Research Center, McLean Hospital/Harvard Medical School, 115 Mill Street, Belmont, MA 02478, USA.
| | - Gunnar Sørensen
- Alcohol and Drug Abuse Research Center, McLean Hospital/Harvard Medical School, 115 Mill Street, Belmont, MA 02478, USA
| | - Ditte Dencker
- Laboratory of Neuropsychiatry, Psychiatric Center Copenhagen and University of Copenhagen, Denmark
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Lu C, Shi Z, Sun X, Pan R, Chen S, Li Y, Qu L, Sun L, Dang H, Bu L, Chen L, Liu X. Kai Xin San aqueous extract improves Aβ 1-40-induced cognitive deficits on adaptive behavior learning by enhancing memory-related molecules expression in the hippocampus. JOURNAL OF ETHNOPHARMACOLOGY 2017; 201:73-81. [PMID: 27751826 DOI: 10.1016/j.jep.2016.10.002] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/04/2015] [Revised: 09/18/2016] [Accepted: 10/03/2016] [Indexed: 06/06/2023]
Abstract
ETHNOPHARMACOLOGICAL RELEVANCE Kai Xin San (KXS), a traditional formula of Chinese medicine, has been used to treat dementia. AIM OF THE STUDY The present study aimed to investigate its ameliorating effects on Aβ1-40-induced cognitive impairment in rats using a series of novel reward-directed instrumental learning tasks, and to determine its possible mechanism of action. MATERIALS AND METHODS Rats were pretreated with KXS aqueous extract (0.72 and 1.44g/kg, p.o.) for 10 days, and were trained to gain reward reinforcement by lever pressing at the meantime. Thereafter, rats received a bilateral microinjection of Aβ1-40 in CA1 regions of the hippocampus. Cognitive performance was evaluated with the goal directed (higher response ratio) and habit (visual signal discrimination and extinction) learning tasks, as well as on the levels of memory-related biochemical parameters and molecules. RESULTS Our findings first demonstrated that KXS can improve Aβ1-40-induced amnesia in RDIL via enhancing the comprehension of action-outcome association and the utilization of cue information to guide behavior. Then, its ameliorating effects should be attributed to the modulation of memory-related molecules in the hippocampus. CONCLUSION In conclusion, KXS has the potential to prevent and/or delay the deterioration of cognitive impairment in AD.
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Affiliation(s)
- Cong Lu
- Research Center for Pharmacology & Toxicology, Institute of Medicinal Plant Development (IMPLAD), Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China.
| | - Zhe Shi
- Research Center for Pharmacology & Toxicology, Institute of Medicinal Plant Development (IMPLAD), Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
| | - Xiuping Sun
- Research Center for Pharmacology & Toxicology, Institute of Medicinal Plant Development (IMPLAD), Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
| | - Ruile Pan
- Research Center for Pharmacology & Toxicology, Institute of Medicinal Plant Development (IMPLAD), Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
| | - Shanguang Chen
- China Astronaut Research and Training Center, Beijing, China
| | - Yinghui Li
- China Astronaut Research and Training Center, Beijing, China
| | - Lina Qu
- China Astronaut Research and Training Center, Beijing, China
| | - Lihua Sun
- Chinese Academy of Chinese Medical Sciences, Beijing, China
| | - Haixia Dang
- Chinese Academy of Chinese Medical Sciences, Beijing, China
| | - Lanlan Bu
- Hunan University of Traditional Chinese Medicine, Changsha, Hunan, China
| | - Lingling Chen
- Hunan University of Traditional Chinese Medicine, Changsha, Hunan, China
| | - Xinmin Liu
- Research Center for Pharmacology & Toxicology, Institute of Medicinal Plant Development (IMPLAD), Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China; Hunan University of Traditional Chinese Medicine, Changsha, Hunan, China.
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17
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α-Isocubebenol alleviates scopolamine-induced cognitive impairment by repressing acetylcholinesterase activity. Neurosci Lett 2017; 638:121-128. [DOI: 10.1016/j.neulet.2016.12.012] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2016] [Revised: 11/29/2016] [Accepted: 12/06/2016] [Indexed: 01/09/2023]
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Mao LM, Wang HH, Wang JQ. Antagonism of Muscarinic Acetylcholine Receptors Alters Synaptic ERK Phosphorylation in the Rat Forebrain. Neurochem Res 2016; 42:1202-1210. [PMID: 28032295 DOI: 10.1007/s11064-016-2157-9] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2016] [Revised: 12/08/2016] [Accepted: 12/19/2016] [Indexed: 11/25/2022]
Abstract
Acetylcholine (ACh) is a key transmitter in the mesocorticolimbic circuit. By interacting with muscarinic ACh receptors (mAChR) enriched in the circuit, ACh actively regulates various neuronal and synaptic activities. The extracellular signal-regulated kinase (ERK) is one of members of the mitogen-activated protein kinase family and is subject to the regulation by dopamine receptors, although the regulation of ERKs by limbic mAChRs is poorly understood. In this study, we investigated the role of mAChRs in the regulation of ERK phosphorylation (activation) in the mesocorticolimbic system of adult rat brains in vivo. We targeted a sub-pool of ERKs at synaptic sites. We found that a systemic injection of the mAChR antagonist scopolamine increased phosphorylation of synaptic ERKs in the striatum (caudate putamen and nucleus accumbens) and medial prefrontal cortex (mPFC). Increases in ERK phosphorylation in both forebrain regions were rapid and transient. Notably, pretreatment with a dopamine D1 receptor (D1R) antagonist SCH23390 blocked the scopolamine-stimulated ERK phosphorylation in these brain regions, while a dopamine D2 receptor antagonist eticlopride did not. Scopolamine and SCH23390 did not change the amount of total ERK proteins. These results demonstrate that mAChRs inhibit synaptic ERK phosphorylation in striatal and mPFC neurons under normal conditions. Blockade of this inhibitory mAChR tone leads to the upregulation of ERK phosphorylation likely through a mechanism involving the level of D1R activity.
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Affiliation(s)
- Li-Min Mao
- Department of Basic Medical Science, School of Medicine, University of Missouri-Kansas City, 2411 Holmes Street, Kansas City, MO, 64108, USA
| | - Henry H Wang
- Department of Basic Medical Science, School of Medicine, University of Missouri-Kansas City, 2411 Holmes Street, Kansas City, MO, 64108, USA
| | - John Q Wang
- Department of Basic Medical Science, School of Medicine, University of Missouri-Kansas City, 2411 Holmes Street, Kansas City, MO, 64108, USA. .,Department of Anesthesiology, School of Medicine, University of Missouri-Kansas City, Kansas City, MO, 64108, USA.
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19
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Mondola P, Damiano S, Sasso A, Santillo M. The Cu, Zn Superoxide Dismutase: Not Only a Dismutase Enzyme. Front Physiol 2016; 7:594. [PMID: 27965593 PMCID: PMC5126113 DOI: 10.3389/fphys.2016.00594] [Citation(s) in RCA: 78] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2016] [Accepted: 11/15/2016] [Indexed: 01/09/2023] Open
Abstract
The Cu,Zn superoxide dismutase (SOD1) is an ubiquitary cytosolic dimeric carbohydrate free molecule, belonging to a family of isoenzymes involved in the scavenger of superoxide anions. This effect certainly represents the main and well known function ascribed to this enzyme. Here we highlight new aspects of SOD1 physiology that point out some inedited effects of this enzyme in addition to the canonic role of oxygen radical enzymatic dismutation. In the last two decades our research group produced many data obtained in in vitro studies performed in many cellular lines, mainly neuroblastoma SK-N-BE cells, indicating that this enzyme is secreted either constitutively or after depolarization induced by high extracellular K+ concentration. In addition, we gave many experimental evidences showing that SOD1 is able to stimulate, through muscarinic M1 receptor, pathways involving ERK1/2, and AKT activation. These effects are accompanied with an intracellular calcium increase. In the last part of this review we describe researches that link deficient extracellular secretion of mutant SOD1G93A to its intracellular accumulation and toxicity in NSC-34 cells. Alternatively, SOD1G93A toxicity has been attributed to a decrease of Km for H2O2 with consequent OH radical formation. Interestingly, this last inedited effect of SOD1G93A could represent a gain of function that could be involved in the pathogenesis of familial Amyotrophic Lateral Sclerosis (fALS).
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Affiliation(s)
- Paolo Mondola
- Dipartimento di Medicina Clinica e Chirurgia, Unità di Fisiologia Umana, Università degli Studi di Napoli "Federico II," Napoli, Italy
| | - Simona Damiano
- Dipartimento di Medicina Clinica e Chirurgia, Unità di Fisiologia Umana, Università degli Studi di Napoli "Federico II," Napoli, Italy
| | - Anna Sasso
- Dipartimento di Medicina Clinica e Chirurgia, Unità di Fisiologia Umana, Università degli Studi di Napoli "Federico II," Napoli, Italy
| | - Mariarosaria Santillo
- Dipartimento di Medicina Clinica e Chirurgia, Unità di Fisiologia Umana, Università degli Studi di Napoli "Federico II," Napoli, Italy
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Olianas MC, Dedoni S, Onali P. Protection from interferon-β-induced neuronal apoptosis through stimulation of muscarinic acetylcholine receptors coupled to ERK1/2 activation. Br J Pharmacol 2016; 173:2910-28. [PMID: 27474091 DOI: 10.1111/bph.13570] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2016] [Revised: 06/30/2016] [Accepted: 07/20/2016] [Indexed: 11/29/2022] Open
Abstract
BACKGROUND AND PURPOSE Although clinically useful for their immunomodulatory, antiproliferative and antiviral properties, type I interferons (IFNs) are involved in the pathogenesis of several neurodegenerative/neuroinflammatory diseases. In the present study, we investigated the ability of cholinergic stimulation to protect from IFN-β-induced neuronal apoptosis. EXPERIMENTAL APPROACH The effects of the ACh receptor agonist carbachol (CCh) on IFN-β-induced apoptosis of human SH-SY5Y neuroblastoma cells were examined by using western blots, immunofluorescence and cytofluorimetry. The involvement of muscarinic acetylcholine receptors (mAChRs) was assessed by using selective antagonists and siRNA transfection. Pharmacological inhibitors and overexpression of ERK2 and an ERK2 constitutively active form (ERK2-CA) were employed to study ERK1/2 signalling. The effects of oxotremorine-M (Oxo-M) on IFN-β-induced apoptosis of mouse hippocampal neurons were examined by measuring cleaved caspase 3 expression. KEY RESULTS In SH-SY5Y cells, CCh inhibited IFN-β-induced mitochondrial cytochrome c release, activation of caspases 9, 7 and 3, PARP cleavage and DNA fragmentation. The anti-apoptotic effect of CCh was mediated by M3 receptors, blocked by Gq/11 antagonist YM254890 and PKC inhibitor Go 6983, impaired by inhibition of ERK1/2 pathway, potentiated by overexpression of ERK2 and mimicked by ERK2-CA. Blockade of JNK activation enhanced the CCh anti-apoptotic response. IFN-β inhibited JNK activation and up-regulated CCh-induced ERK1/2 signalling. In hippocampal neurons, Oxo-M reduced IFN-β-induced apoptosis; this effect was antagonized by blockade of M1 /M3 receptors and ERK1/2. CONCLUSIONS AND IMPLICATIONS Stimulation of mAChRs counteracted IFN-β-induced neuronal apoptosis through the activation of ERK1/2 signalling. The data indicate that activation of ERK1/2-coupled mAChRs may be an effective strategy for preventing IFNs neurotoxicity.
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Affiliation(s)
- Maria C Olianas
- Laboratory of Cellular and Molecular Pharmacology, Section of Neurosciences and Clinical Pharmacology, Department of Biomedical Sciences, University of Cagliari, Cagliari, Italy
| | - Simona Dedoni
- Laboratory of Cellular and Molecular Pharmacology, Section of Neurosciences and Clinical Pharmacology, Department of Biomedical Sciences, University of Cagliari, Cagliari, Italy
| | - Pierluigi Onali
- Laboratory of Cellular and Molecular Pharmacology, Section of Neurosciences and Clinical Pharmacology, Department of Biomedical Sciences, University of Cagliari, Cagliari, Italy.
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Damar U, Gersner R, Johnstone JT, Schachter S, Rotenberg A. Huperzine A as a neuroprotective and antiepileptic drug: a review of preclinical research. Expert Rev Neurother 2016; 16:671-80. [PMID: 27086593 DOI: 10.1080/14737175.2016.1175303] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
Huperzine A (HupA) is an acetylcholinesterase (AChE) inhibitor extracted from Huperzia Serrata, a firmoss, which has been used for various diseases in traditional Chinese medicine for fever and inflammation. More recently, it has been used in Alzheimer's disease and other forms of dementia with a presumed mechanism of action via central nicotinic and muscarinic receptors. HupA is marketed as a dietary supplement in the U.S. This article reviews newly proposed neuroprotective and anticonvulsant HupA properties based on animal studies. HupA exerts its effects mainly via α7nAChRs and α4β2nAChRs, thereby producing a potent anti-inflammatory response by decreasing IL-1β, TNF-α protein expression, and suppressing transcriptional activation of NF-κB signaling. Thus, it provides protection from excitotoxicity and neuronal death as well as increase in GABAergic transmission associated with anticonvulsant activity.
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Affiliation(s)
- U Damar
- a F.M. Kirby Neurobiology Center, Department of Neurology , Boston Children's Hospital, Harvard Medical School , Boston , MA , USA
| | - R Gersner
- a F.M. Kirby Neurobiology Center, Department of Neurology , Boston Children's Hospital, Harvard Medical School , Boston , MA , USA
| | - J T Johnstone
- b Research and Development - Neurology , Biscayne Pharmaceuticals, Inc ., Miami , FL , USA
| | - S Schachter
- c Departments of Neurology, Beth Israel Deaconess Medical Center, Massachusetts General Hospital , Harvard Medical School , Boston , MA , USA
| | - A Rotenberg
- a F.M. Kirby Neurobiology Center, Department of Neurology , Boston Children's Hospital, Harvard Medical School , Boston , MA , USA
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Hopper S, Udawela M, Scarr E, Dean B. Allosteric modulation of cholinergic system: Potential approach to treating cognitive deficits of schizophrenia. World J Pharmacol 2016; 5:32-43. [DOI: 10.5497/wjp.v5.i1.32] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/19/2015] [Revised: 11/26/2015] [Accepted: 01/04/2016] [Indexed: 02/06/2023] Open
Abstract
Schizophrenia is a psychiatric disorder affecting approximately 1% of the population worldwide and is characterised by the presence of positive and negative symptoms and cognitive deficits. Whilst current therapeutics ameliorate positive symptoms, they are largely ineffective in improving negative symptoms and cognitive deficits. The cholinergic neurotransmitter system heavily influences cognitive function and there is evidence that implicates disruption of the central cholinergic system in schizophrenia. Historically, targeting the cholinergic system has been impeded by poor selectivity leading to intolerable side effects warranting the need to develop more targeted therapeutic compounds. In this review we will summarise evidence supporting the roles of the cholinergic system, particularly the muscarinic M1 receptor, in the pathophysiology of schizophrenia and discuss the potential of a promising new class of candidate compounds, allosteric ligands, for addressing the difficulties involved in targeting this system. The body of evidence presented here highlights the dysfunction of the cholinergic system in schizophrenia and that targeting this system by taking advantage of allosteric ligands is having clinically meaningful effect on cognitive deficits.
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The Ameliorating Effect of Myrrh on Scopolamine-Induced Memory Impairments in Mice. EVIDENCE-BASED COMPLEMENTARY AND ALTERNATIVE MEDICINE 2015; 2015:925432. [PMID: 26635888 PMCID: PMC4655272 DOI: 10.1155/2015/925432] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/25/2015] [Accepted: 10/11/2015] [Indexed: 12/28/2022]
Abstract
Myrrh has been used since ancient times for the treatment of various diseases such as inflammatory diseases, gynecological diseases, and hemiplegia. In the present study, we investigated the effects of aqueous extracts of myrrh resin (AEM) on scopolamine-induced memory impairments in mice. AEM was estimated with (2E,5E)-6-hydroxy-2,6-dimethylhepta-2,4-dienal as a representative constituent by HPLC. The oral administration of AEM for 7 days significantly reversed scopolamine-induced reduction of spontaneous alternation in the Y-maze test. In the passive avoidance task, AEM also restored the decreased latency time of the retention trial by scopolamine treatment. In addition, Western blot analysis and Immunohistochemistry revealed that AEM reversed scopolamine-decreased phosphorylation of Akt and extracellular signal-regulated kinase (ERK). Our study demonstrates for the first time that AEM ameliorates the scopolamine-induced memory impairments in mice and increases the phosphorylation of Akt and ERK in the hippocampus of mice brain. These results suggest that AEM has the therapeutic potential in memory impairments.
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Shi Z, Lu C, Sun X, Wang Q, Chen S, Li Y, Qu L, Chen L, Bu L, Liao D, Liu X. Tong Luo Jiu Nao ameliorates Aβ1-40-induced cognitive impairment on adaptive behavior learning by modulating ERK/CaMKII/CREB signaling in the hippocampus. Altern Ther Health Med 2015; 15:55. [PMID: 25888276 PMCID: PMC4380248 DOI: 10.1186/s12906-015-0584-9] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2014] [Accepted: 02/21/2015] [Indexed: 12/25/2022]
Abstract
BACKGROUND Tong Luo Jiu Nao (TLJN), a modern formula of Chinese medicine extracts on the basis of Traditional Chinese Medicine theory, has been used to treat dementia. The present study aimed to investigate its ameliorating effects on Aβ1-40-induced cognitive impairment in rats using a series of novel reward-directed instrumental learning (RDIL) tasks, and to determine its possible mechanism of action. METHODS Rats were pretreated with TLJN extract (0.9 and 1.8 g/kg, p.o.) for 10 daysbefore surgery, and were trained to gain reward reinforcement by lever pressing at the meantime. Thereafter, rats received a bilateral microinjection of Aβ1-40 in CA1 regions of the hippocampus. Cognitive performance was evaluated with the goal directed (higher response ratio) and habit (visual signal discrimination and extinction) learning tasks, as well as on the levels of biochemical parameters and molecules. RESULTS Our findings first demonstrated that TLJN can improve Aβ1-40-induced amnesia in RDIL via enhancing the comprehension of action-outcome association and the utilization of cue information to guide behavior. Then, its ameliorating effects should attribute to the modulation of ERK/CaMKII/CREB signaling in the hippocampus. CONCLUSION TLJN can markedly enhance cognitions of Aβ1-40 microinjection animal model in adaptive behavioral tasks. It has the potential, possibly as complementary and alternative therapy, to prevent and/or delay the deterioration of cognitive impairment in AD.
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Giovannini MG, Lana D, Pepeu G. The integrated role of ACh, ERK and mTOR in the mechanisms of hippocampal inhibitory avoidance memory. Neurobiol Learn Mem 2015; 119:18-33. [PMID: 25595880 DOI: 10.1016/j.nlm.2014.12.014] [Citation(s) in RCA: 68] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2014] [Revised: 12/29/2014] [Accepted: 12/30/2014] [Indexed: 11/28/2022]
Abstract
The purpose of this review is to summarize the present knowledge on the interplay among the cholinergic system, Extracellular signal-Regulated Kinase (ERK) and Mammalian Target of Rapamycin (mTOR) pathways in the development of short and long term memories during the acquisition and recall of the step-down inhibitory avoidance in the hippocampus. The step-down inhibitory avoidance is a form of associative learning that is acquired in a relatively simple one-trial test through several sensorial inputs. Inhibitory avoidance depends on the integrated activity of hippocampal CA1 and other brain areas. Recall can be performed at different times after acquisition, thus allowing for the study of both short and long term memory. Among the many neurotransmitter systems involved, the cholinergic neurons that originate in the basal forebrain and project to the hippocampus are of crucial importance in inhibitory avoidance processes. Acetylcholine released from cholinergic fibers during acquisition and/or recall of behavioural tasks activates muscarinic and nicotinic acetylcholine receptors and brings about a long-lasting potentiation of the postsynaptic membrane followed by downstream activation of intracellular pathway (ERK, among others) that create conditions favourable for neuronal plasticity. ERK appears to be salient not only in long term memory, but also in the molecular mechanisms underlying short term memory formation in the hippocampus. Since ERK can function as a biochemical coincidence detector in response to extracellular signals in neurons, the activation of ERK-dependent downstream effectors is determined, in part, by the duration of ERK phosphorylation itself. Long term memories require protein synthesis, that in the synapto-dendritic compartment represents a direct mechanism that can produce rapid changes in protein content in response to synaptic activity. mTOR in the brain regulates protein translation in response to neuronal activity, thereby modulating synaptic plasticity and long term memory formation. Some studies demonstrate a complex interplay among the cholinergic system, ERK and mTOR. It has been shown that co-activation of muscarinic acetylcholine receptors and β-adrenergic receptors facilitates the conversion of short term to long term synaptic plasticity through an ERK- and mTOR-dependent mechanism which requires translation initiation. It seems therefore that the complex interplay among the cholinergic system, ERK and mTOR is crucial in the development of new inhibitory avoidance memories in the hippocampus.
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Affiliation(s)
- Maria Grazia Giovannini
- Department of Health Sciences, Section of Clinical Pharmacology and Oncology, University of Florence, Viale Pieraccini 6, 50139 Firenze, Italy.
| | - Daniele Lana
- Department of Health Sciences, Section of Clinical Pharmacology and Oncology, University of Florence, Viale Pieraccini 6, 50139 Firenze, Italy.
| | - Giancarlo Pepeu
- Department of Neuroscience, Psychology, Drug Research and Child Health, Division of Pharmacology and Toxicology, University of Florence, Viale Pieraccini 6, 50139 Firenze, Italy.
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Kow RL, Cheng EM, Jiang K, Le JH, Stella N, Nathanson NM. Muscarinic M1 receptor and cannabinoid CB1 receptor do not modulate paraoxon-induced seizures. Pharmacol Res Perspect 2014; 3:e00100. [PMID: 25692018 PMCID: PMC4317231 DOI: 10.1002/prp2.100] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2014] [Revised: 08/19/2014] [Accepted: 09/16/2014] [Indexed: 11/24/2022] Open
Abstract
One of the major signs of severe organophosphate poisoning is seizures. Previous studies have shown that both muscarinic agonist- and organophosphate-induced seizures require activation of muscarinic acetylcholine receptors in the central nervous system. Seizures induced by the muscarinic agonist pilocarpine require the M1 receptor and are modulated by cannabinoid CB1 receptors. In this study, we determined whether M1 and CB1 receptors also regulated seizures induced by the organophosphate paraoxon. We found no differences in seizures induced by paraoxon in wild-type (WT) and M1 knockout (KO) mice, indicating that in contrast to pilocarpine seizures, M1 receptors are not required for paraoxon seizures. Furthermore, we found that pilocarpine administration resulted in seizure-independent activation of ERK in the hippocampus in a M1 receptor-dependent manner, while paraoxon did not induce seizure-independent activation of ERK in the mouse hippocampus. This shows that pilocarpine and paraoxon activated M1 receptors in the hippocampus to different extents. There were no differences in seizures induced by paraoxon in WT and CB1 KO mice, and neither CB1 agonist nor antagonist administration had significant effects on paraoxon seizures, indicating that, in contrast to pilocarpine seizures, paraoxon seizures are not modulated by CB1 receptors. These results demonstrate that there are fundamental molecular differences in the regulation of seizures induced by pilocarpine and paraoxon.
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Affiliation(s)
- Rebecca L Kow
- Department of Pharmacology, University of Washington Seattle, Washington
| | - Eugene M Cheng
- Department of Pharmacology, University of Washington Seattle, Washington
| | - Kelly Jiang
- Department of Pharmacology, University of Washington Seattle, Washington
| | - Joshua H Le
- Department of Pharmacology, University of Washington Seattle, Washington
| | - Nephi Stella
- Department of Pharmacology, University of Washington Seattle, Washington
| | - Neil M Nathanson
- Department of Pharmacology, University of Washington Seattle, Washington
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Zhao Y, Li J, Tang Q, Gao J, Chen C, Jing L, Zhang P, Li S. Apolipoprotein E mimetic peptide protects against diffuse brain injury. Neural Regen Res 2014; 9:463-73. [PMID: 25206840 PMCID: PMC4153503 DOI: 10.4103/1673-5374.130060] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/25/2013] [Indexed: 01/11/2023] Open
Abstract
Apolipoprotein E plays a crucial role in inhibiting chronic neurodegenerative processes. However, its impact on neurological function following diffuse brain injury is still unclear. This study was designed to evaluate the therapeutic effects and mechanisms of action of apolipoprotein E mimetic peptide on diffuse brain injury. Apolipoprotein E mimetic peptide was administered into the caudal vein of rats with diffuse brain injury before and after injury. We found that apolipoprotein E mimetic peptide significantly decreased the number of apoptotic neurons, reduced extracellular signal-regulated kinase1/2 phosphorylation, down-regulated Bax and cytochrome c expression, decreased malondialdehyde content, and increased superoxide dismutase activity in a dose-dependent manner. These experimental findings demonstrate that apolipoprotein E mimetic peptide improves learning and memory function and protects against diffuse brain injury-induced apoptosis by inhibiting the extracellular signal-regulated kinase1/2-Bax mitochondrial apoptotic pathway.
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Affiliation(s)
- Yaning Zhao
- College of Rehabilitation, Hebei United University, Tangshan, Hebei Province, China
| | - Jianmin Li
- Affiliated Hospital of Hebei United University, Tangshan, Hebei Province, China
| | - Qiqun Tang
- College of Rehabilitation, Hebei United University, Tangshan, Hebei Province, China
| | - Junling Gao
- College of Rehabilitation, Hebei United University, Tangshan, Hebei Province, China
| | - Changxiang Chen
- College of Rehabilitation, Hebei United University, Tangshan, Hebei Province, China
| | - Liwei Jing
- College of Rehabilitation, Hebei United University, Tangshan, Hebei Province, China
| | - Pan Zhang
- College of Rehabilitation, Hebei United University, Tangshan, Hebei Province, China
| | - Shuxing Li
- College of Rehabilitation, Hebei United University, Tangshan, Hebei Province, China
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David O, Barrera I, Chinnakkaruppan A, Kaphzan H, Nakazawa T, Yamamoto T, Rosenblum K. Dopamine-induced tyrosine phosphorylation of NR2B (Tyr1472) is essential for ERK1/2 activation and processing of novel taste information. Front Mol Neurosci 2014; 7:66. [PMID: 25100942 PMCID: PMC4103512 DOI: 10.3389/fnmol.2014.00066] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2014] [Accepted: 07/02/2014] [Indexed: 01/14/2023] Open
Abstract
Understanding the heterosynaptic interaction between glutamatergic and neuromodulatory synapses is highly important for revealing brain function in health and disease. For instance, the interaction between dopamine and glutamate neurotransmission is vital for memory and synaptic plasticity consolidation, and it is known to converge on extracellular signal-regulated kinase (ERK)-MAPK signaling in neurons. Previous studies suggest that dopamine induces N-methyl-D-aspartate (NMDA) receptor phosphorylation at the NR2B Y1472 subunit, influencing receptor internalization at the synaptic plasma membrane. However, it is unclear whether this phosphorylation is upstream to and/or necessary for ERK1/2 activation, which is known to be crucial for synaptic plasticity and memory consolidation. Here, we tested the hypothesis that tyrosine phosphorylation of NR2B at Y1472 is correlated with ERK1/2 activation by dopamine and necessary for it as well. We find that dopamine receptor D1, but not D2, activates ERK1/2 and leads to NR2BY1472 phosphorylation in the mature hippocampus and cortex. Moreover, our results indicate that NR2B Y1472 phosphorylation is necessary for ERK1/2 activation. Importantly, application of dopamine or the D1 receptor agonist SKF38393 to hippocampal slices from NR2B F1472 mutant mice did not result in ERK1/2 activation, suggesting this site is not only correlated with ERK1/2 activation by dopamine stimulation, but also necessary for it. In addition, NR2B F1472 mice show impairment in learning of attenuation of taste neophobia but not associative taste learning. Our study shows that the dopaminergic and glutamatergic transmission converge on the NMDA receptor itself, at the Y1472 site of the NR2B subunit, and that this convergence is essential for ERK1/2 activation in the mature brain and for processing new sensory information in the cortex.
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Affiliation(s)
- Orit David
- Sagol Department of Neurobiology, University of Haifa Haifa, Israel
| | - Iliana Barrera
- Sagol Department of Neurobiology, University of Haifa Haifa, Israel
| | | | - Hanoch Kaphzan
- Sagol Department of Neurobiology, University of Haifa Haifa, Israel
| | - Takanobu Nakazawa
- Division of Oncology, Institute of Medical Science, University of Tokyo Tokyo, Japan
| | - Tadashi Yamamoto
- Division of Oncology, Institute of Medical Science, University of Tokyo Tokyo, Japan
| | - Kobi Rosenblum
- Sagol Department of Neurobiology, University of Haifa Haifa, Israel ; Center for Gene Manipulation in the Brain, University of Haifa Haifa, Israel
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Park SJ, Shin EJ, Min SS, An J, Li Z, Hee Chung Y, Hoon Jeong J, Bach JH, Nah SY, Kim WK, Jang CG, Kim YS, Nabeshima YI, Nabeshima T, Kim HC. Inactivation of JAK2/STAT3 signaling axis and downregulation of M1 mAChR cause cognitive impairment in klotho mutant mice, a genetic model of aging. Neuropsychopharmacology 2013; 38:1426-37. [PMID: 23389690 PMCID: PMC3682136 DOI: 10.1038/npp.2013.39] [Citation(s) in RCA: 58] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
We previously reported cognitive dysfunction in klotho mutant mice. In the present study, we further examined novel mechanisms involved in cognitive impairment in these mice. Significantly decreased janus kinase 2 (JAK2) and signal transducer and activator of transcription3 (STAT3) phosphorylation were observed in the hippocampus of klotho mutant mice. A selective decrease in protein expression and binding density of the M1 muscarinic cholinergic receptor (M1 mAChR) was observed in these mice. Cholinergic parameters (ie, acetylcholine (ACh), choline acetyltransferase (ChAT), and acetylcholinesterase (AChE)) and NMDAR-dependent long-term potentiation (LTP) were significantly impaired in klotho mutant mice. McN-A-343 (McN), an M1 mAChR agonist, significantly attenuated these impairments. AG490 (AG), a JAK2 inhibitor, counteracted the attenuating effects of McN, although AG did not significantly alter the McN-induced effect on AChE. Furthermore, AG significantly inhibited the attenuating effects of McN on decreased NMDAR-dependent LTP, protein kinase C βII, p-ERK, p-CREB, BDNF, and p-JAK2/p-STAT3-expression in klotho mutant mice. In addition, k252a, a BDNF receptor tyrosine kinase B (TrkB) inhibitor, significantly counteracted McN effects on decreased ChAT, ACh, and M1 mAChR and p-JAK2/p-STAT3 expression. McN-induced effects on cognitive impairment in klotho mutant mice were consistently counteracted by either AG or k252a. Our results suggest that inactivation of the JAK2/STAT3 signaling axis and M1 mAChR downregulation play a critical role in cognitive impairment observed in klotho mutant mice.
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Affiliation(s)
- Seok-Joo Park
- Neuropsychopharmacology and Toxicology Program, Department of Pharmacy, College of Pharmacy, Kangwon National University, Chunchon, South Korea,Ilsong Institute of Life Science, Hallym University, Anyang, South Korea
| | - Eun-Joo Shin
- Neuropsychopharmacology and Toxicology Program, Department of Pharmacy, College of Pharmacy, Kangwon National University, Chunchon, South Korea
| | - Sun Seek Min
- Department of Physiology and Biophysics, College of Medicine, Eulji University, Daejeon, South Korea,Department of Physiology and Biophysics, College of Medicine, Eulji University, Daejeon 301-746, South Korea, Tel: +82 42 259 1633, Fax: +82 42 259 1639, E-mail:
| | - Jihua An
- Department of Physiology and Biophysics, College of Medicine, Eulji University, Daejeon, South Korea
| | - Zhengyi Li
- Neuropsychopharmacology and Toxicology Program, Department of Pharmacy, College of Pharmacy, Kangwon National University, Chunchon, South Korea
| | - Yoon Hee Chung
- Department of Anatomy, College of Medicine, Chung-Ang University, Seoul, South Korea
| | - Ji Hoon Jeong
- Department of Pharmacology, College of Medicine, Chung-Ang University, Seoul, South Korea
| | - Jae-Hyung Bach
- Neuropsychopharmacology and Toxicology Program, Department of Pharmacy, College of Pharmacy, Kangwon National University, Chunchon, South Korea
| | - Seung-Yeol Nah
- Ginsentology Research Laboratory, Department of Physiology, College of Veterinary Medicine and Bio/Molecular Informatics Center, Konkuk University, Seoul, South Korea
| | - Won-Ki Kim
- Department of Neuroscience, College of Medicine, Korea University, Seoul, South Korea
| | - Choon-Gon Jang
- Department of Pharmacology, School of Pharmacy, Sungkyunkwan University, Suwon, South Korea
| | - Yong-Sun Kim
- Ilsong Institute of Life Science, Hallym University, Anyang, South Korea
| | - Yo-ichi Nabeshima
- Laboratory of Molecular Life Science, Institute of Biomedical Research and Innovation, Foundation for Biomedical Research and Innovation, Kobe, Japan
| | - Toshitaka Nabeshima
- Department of Regional Pharmaceutical Care and Science, Graduate School of Pharmaceutical Sciences, Meijo University, Nagoya, Japan
| | - Hyoung-Chun Kim
- Neuropsychopharmacology and Toxicology Program, Department of Pharmacy, College of Pharmacy, Kangwon National University, Chunchon, South Korea,Neuropsychopharmacology and Toxicology Program, Department of Pharmacy, College of Pharmacy, Kangwon National University, Chunchon 200-701, South Korea, Tel: +82 33 250 6917, Fax: +82 33 255 7865, E-mail:
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Kim BK, Tran HYP, Shin EJ, Lee C, Chung YH, Jeong JH, Bach JH, Kim WK, Park DH, Saito K, Nabeshima T, Kim HC. IL-6 attenuates trimethyltin-induced cognitive dysfunction via activation of JAK2/STAT3, M1 mAChR and ERK signaling network. Cell Signal 2013; 25:1348-60. [PMID: 23499905 DOI: 10.1016/j.cellsig.2013.02.017] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2013] [Accepted: 02/19/2013] [Indexed: 12/26/2022]
Abstract
We previously reported that interleukin (IL)-6 deficiency potentiates trimethyltin (TMT)-induced convulsive neurotoxicity. The purpose in this study was to investigate the molecular mechanism by which cytokines affect TMT-induced cognitive impairment. To accomplish this, we examined hippocampal changes in Janus kinase 2 (JAK2)/signal transducer and activator of transcription 3 (STAT3) signaling in relation to cholinergic parameters after TMT treatment in mice genetically deficient in IL-6 (IL-6(-/-)), tumor necrosis factor-α (TNF-α(-/-)), or interferon-γ (IFN-γ(-/-)). The IL-6(-/-) mice were the most susceptible to TMT-induced cognitive dysfunction and exhibited significant decreases in JAK2/STAT3 signaling and M1 muscarinic acetylcholine receptor (mAChR) expression, as well as other cholinergic parameters, compared with wild-type (WT) animals. Recombinant IL-6 protein (rIL-6) significantly attenuated these impairments in TMT-treated IL-6(-/-) mice, whereas an IL-6 receptor antibody potentiated these impairments in TMT-treated WT animals. Inhibition of JAK2 with AG490 or inhibition of cholinergic signaling with the M1 mAChR antagonist dicyclomine counteracted the attenuating effects of rIL-6 on phosphorylated extracellular signal-regulated kinase (ERK) expression, or on cognitive impairment in TMT-treated IL-6(-/-) mice. However, neither AG490 nor dicyclomine significantly attenuated effects of rIL-6 on acetylcholinesterase values. Our results suggest that activation of JAK2/STAT3 signaling and upregulation of the M1 mAChR are essential components of IL-6-mediated memory improvement against TMT toxicity.
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Affiliation(s)
- Beom Keun Kim
- Department of Pharmacology, College of Medicine, Chung-Ang University, Seoul 156-756, South Korea
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Damiano S, Petrozziello T, Ucci V, Amente S, Santillo M, Mondola P. Cu-Zn superoxide dismutase activates muscarinic acetylcholine M1 receptor pathway in neuroblastoma cells. Mol Cell Neurosci 2012; 52:31-7. [PMID: 23147108 DOI: 10.1016/j.mcn.2012.11.001] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2012] [Revised: 10/25/2012] [Accepted: 11/02/2012] [Indexed: 01/25/2023] Open
Abstract
Muscarinic receptors (mAChRs) control several neuronal functions and are widely expressed in the central nervous system (CNS): M1 subtype represents the predominant mAChR in the CNS. Previously, we showed that antioxidant enzyme Cu-Zn superoxide dismutase (SOD1) is secreted by many cellular lines and specifically interacts with cell surface membrane of human neuroblastoma SK-N-BE cells thus activating phospholipase C (PLC) transduction pathway and increasing intracellular calcium concentration ([Ca(2+)](i)). In addition, we demonstrated that a small amount of SOD1 is contained in large core dense vesicles and that it is secreted in response to depolarization induced by elevated extracellular K(+) concentration. In the present study, we investigated the involvement of muscarinic M1 receptors in SOD1-induced activation of PLC transduction pathway. We showed that, in SK-N-BE cells, SOD1 was able to activate muscarinic M1 receptor producing a phosphorylation of ERK 1/2 and Akt in dose- and time-dependent manner. Interestingly, in the presence of the M1 antagonist pirenzepine, ERK 1/2 and Akt phosphorylation induced by SOD1 was remarkably prevented. This effect was mimicked by knocking-down M1 receptor using two sequences of RNA silencing (siRNA). At functional level, siRNAs against M1 receptor were able to prevent the increase in [Ca(2+)](i) induced by SOD1. The same inhibitory effect on [Ca(2+)](i) changes was produced by the M1 antagonist pirenzepine. Collectively, the results of this study demonstrated that SOD1 could activate a transductional pathway through the involvement of M1 muscarinic receptor.
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Affiliation(s)
- Simona Damiano
- Dipartimento di Neuroscienze, Unità di Fisiologia Umana, Università degli Studi di Napoli Federico II, Napoli, Italy
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Connor SA, Maity S, Roy B, Ali DW, Nguyen PV. Conversion of short-term potentiation to long-term potentiation in mouse CA1 by coactivation of -adrenergic and muscarinic receptors. Learn Mem 2012; 19:535-42. [DOI: 10.1101/lm.026898.112] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Moosavi M, Khales GY, Abbasi L, Zarifkar A, Rastegar K. Agmatine protects against scopolamine-induced water maze performance impairment and hippocampal ERK and Akt inactivation. Neuropharmacology 2012; 62:2018-23. [PMID: 22248637 DOI: 10.1016/j.neuropharm.2011.12.031] [Citation(s) in RCA: 56] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2011] [Revised: 12/27/2011] [Accepted: 12/29/2011] [Indexed: 02/08/2023]
Abstract
Cholinergic brain activity plays a significant role in memory. Scopolamine a muscarinic cholinergic antagonist is known to induce impairment in Morris water maze performance, the task which is mainly dependent on the hippocampus. It is suggested that hippocampal ERK and Akt activation play roles in synaptic plasticity and some types of learning and memory. Agmatine, a polyamine derived from l-arginine decarboxylation, is recently shown to exert some neuroprotective effects. This study was aimed to investigate if agmatine could reverse scopolamine-induced memory impairment and possible hippocampal ERK and Akt activity alteration. Adult male Sprague-Dawley rats weighing 200-250 g were randomly assigned into 5 groups. The animals were trained for 3 days in Morris water maze and in day 4 their memory retention was assessed in probe trial which was consisted of a 60 s trial with no platform. Scopolamine (1 mg/kg/ip) or saline were injected 30 min and agmatine (20 or 40 mg/kg/ip) was administered 60 min before each session. The hippocampi were isolated after behavioral studies and western blotting studies on hippocampal lysates were done to determine the levels of activated ERK and Akt. Scopolamine treatment not only impaired water maze learning and memory, but also decreased the amount of phosphorylated (activated) ERK and Akt. Agmatine pre-treatment prevented both the learning impairment and hippocampal ERK and Akt inactivation induced by scopolamine. It seems that agmatine may act as a candidate substance against amnesia.
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Affiliation(s)
- Maryam Moosavi
- Shiraz Neuroscience Research Center and department of Physiology, Shiraz University of Medical Sciences, Zand Street, Shiraz, Iran.
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Abstract
Schizophrenia is a devastating disease with several broad symptom clusters and the current monoamine-based treatments do not adequately treat the disease, especially negative and cognitive symptoms. A proposed alternative approach for treating schizophrenia is through the use of compounds that activate certain muscarinic receptor subtypes, the so-called muscarinic cholinergic hypothesis theory. This theory has been revitalized with a number of recent and provocative findings including postmortem reports in schizophrenia patients showing decreased numbers of muscarinic M(1) and M(4) receptors in brain regions associated with schizophrenia as well as decreased muscarinic receptors in an in vivo imaging study. Studies with M(4) knockout mice have shown that there is a reciprocal relationship between M(4) and dopamine receptor function, and a number of muscarinic agonists have shown antidopaminergic activity in a variety of preclinical assays predictive of antipsychotic efficacy in the clinic. Furthermore, the M(1)/M(4) preferring partial agonist xanomeline has been shown to have antipsychotic-like and pro-cognitive activity in preclinical models and in clinical trials to decrease psychotic-like behaviors in Alzheimer's patients and positive, negative, and cognitive symptoms in patients with schizophrenia. Therefore, we propose that an agonist with M(1) and M(4) interactions would effectively treat core symptom clusters associated with schizophrenia. Currently, research is focused on developing subtype-selective muscarinic agonists and positive allosteric modulators that have reduced propensity for parasympathetic side-effects, but retain the therapeutic benefit observed with their less selective predecessors.
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Affiliation(s)
- David L McKinzie
- Lilly Research Laboratories, Eli Lilly and Co., Indianapolis, IN 46285, USA.
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Ragozzino ME, Artis S, Singh A, Twose TM, Beck JE, Messer WS. The selective M1 muscarinic cholinergic agonist CDD-0102A enhances working memory and cognitive flexibility. J Pharmacol Exp Ther 2011; 340:588-94. [PMID: 22135384 DOI: 10.1124/jpet.111.187625] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Various neurodegenerative diseases and psychiatric disorders are marked by alterations in brain cholinergic function and cognitive deficits. Efforts to alleviate such deficits have been limited by a lack of selective M(1) muscarinic agonists. 5-(3-Ethyl-1,2,4-oxadiazol-5-yl)-1,4,5,6-tetrahydropyrimidine hydrochloride (CDD-0102A) is a partial agonist at M(1) muscarinic receptors with limited activity at other muscarinic receptor subtypes. The present studies investigated the effects of CDD-0102A on working memory and strategy shifting in rats. CDD-0102A administered intraperitoneally 30 min before testing at 0.1, 0.3, and 1 mg/kg significantly enhanced delayed spontaneous alternation performance in a four-arm cross maze, suggesting improvement in working memory. In separate experiments, CDD-0102A had potent enhancing effects on learning and switching between a place and visual cue discrimination. Treatment with CDD-0102A did not affect acquisition of either a place or visual cue discrimination. In contrast, CDD-0102A at 0.03 and 0.1 mg/kg significantly enhanced a shift between a place and visual cue discrimination. Analysis of the errors in the shift to the place or shift to the visual cue strategy revealed that in both cases CDD-0102A significantly increased the ability to initially inhibit a previously relevant strategy and maintain a new, relevant strategy once selected. In anesthetized rats, the minimum dose required to induce salivation was approximately 0.3 mg/kg i.p. Salivation increased with dose, and the estimated ED(50) was 2.0 mg/kg. The data suggest that CDD-0102A has unique memory and cognitive enhancing properties that might be useful in the treatment of neurological disorders at doses that do not produce adverse effects such as salivation.
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Affiliation(s)
- Michael E Ragozzino
- Department of Psychology, Laboratory of Integrative Neuroscience, University of Illinois at Chicago, Chicago, Illinois, USA
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Maehara S, Satow A, Hikichi H, Ohta H. Antipsychotic effects of N-desmethylclozapine on sensorimotor gating function in rats — Possible involvement of activation of M1 muscarinic receptors. Eur J Pharmacol 2011; 667:242-9. [DOI: 10.1016/j.ejphar.2011.05.063] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2011] [Revised: 05/09/2011] [Accepted: 05/22/2011] [Indexed: 12/01/2022]
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Serotonin signaling is associated with lower amyloid-β levels and plaques in transgenic mice and humans. Proc Natl Acad Sci U S A 2011; 108:14968-73. [PMID: 21873225 DOI: 10.1073/pnas.1107411108] [Citation(s) in RCA: 241] [Impact Index Per Article: 18.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Aggregation of amyloid-β (Aβ) as toxic oligomers and amyloid plaques within the brain appears to be the pathogenic event that initiates Alzheimer's disease (AD) lesions. One therapeutic strategy has been to reduce Aβ levels to limit its accumulation. Activation of certain neurotransmitter receptors can regulate Aβ metabolism. We assessed the ability of serotonin signaling to alter brain Aβ levels and plaques in a mouse model of AD and in humans. In mice, brain interstitial fluid (ISF) Aβ levels were decreased by 25% following administration of several selective serotonin reuptake inhibitor (SSRI) antidepressant drugs. Similarly, direct infusion of serotonin into the hippocampus reduced ISF Aβ levels. Serotonin-dependent reductions in Aβ were reversed if mice were pretreated with inhibitors of the extracellular regulated kinase (ERK) signaling cascade. Chronic treatment with an SSRI, citalopram, caused a 50% reduction in brain plaque load in mice. To test whether serotonin signaling could impact Aβ plaques in humans, we retrospectively compared brain amyloid load in cognitively normal elderly participants who were exposed to antidepressant drugs within the past 5 y to participants who were not. Antidepressant-treated participants had significantly less amyloid load as quantified by positron emission tomography (PET) imaging with Pittsburgh Compound B (PIB). Cumulative time of antidepressant use within the 5-y period preceding the scan correlated with less plaque load. These data suggest that serotonin signaling was associated with less Aβ accumulation in cognitively normal individuals.
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Davis AA, Heilman CJ, Brady AE, Miller NR, Fuerstenau-Sharp M, Hanson BJ, Lindsley CW, Conn PJ, Lah JJ, Levey AI. Differential effects of allosteric M(1) muscarinic acetylcholine receptor agonists on receptor activation, arrestin 3 recruitment, and receptor downregulation. ACS Chem Neurosci 2010; 1:542-551. [PMID: 20835371 DOI: 10.1021/cn100011e] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
Abstract
Muscarinic acetylcholine receptors (mAChRs) are drug targets for multiple neurodegenerative and neuropsychiatric disorders, but the full therapeutic potential of mAChR-targeted drugs has not been realized, mainly because of a lack of subtype-selective agonists. Recent advances have allowed the development of highly selective agonists that bind to an allosteric site on the M(1) mAChR that is spatially distinct from the orthosteric acetylcholine binding site, but less is known about the profile of intracellular signals activated by orthosteric versus allosteric M(1) mAChR agonists. We investigated the activation and regulatory mechanisms of two structurally distinct allosteric M(1) mAChR agonists, AC260584 and TBPB. We show that allosteric agonists potently activate multiple signal transduction pathways linked to the M(1) mAChR receptor but, compared to orthosteric agonists, much less efficiently recruit arrestin 3, a protein involved in regulation of G-protein coupled receptor signaling. Consistent with decreased arrestin recruitment, both allosteric agonists showed blunted responses in measurements of receptor desensitization, internalization, and downregulation. These results advance the understanding of mAChR biology and may shed light on unanticipated differences in the pharmacology of orthosteric vs. allosteric agonists that might be capitalized upon for drug development for the treatment of CNS diseases.
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Affiliation(s)
- Albert A. Davis
- Center for Neurodegenerative Disease and Department of Neurology, Emory University School of Medicine, Atlanta, Georgia 30322
| | - Craig J. Heilman
- Center for Neurodegenerative Disease and Department of Neurology, Emory University School of Medicine, Atlanta, Georgia 30322
| | - Ashley E. Brady
- Department of Pharmacology, Vanderbilt University Medical Center, Nashville, Tennessee 37232
| | - Nicole R. Miller
- Department of Pharmacology, Vanderbilt University Medical Center, Nashville, Tennessee 37232
| | | | | | - Craig W. Lindsley
- Department of Pharmacology, Vanderbilt University Medical Center, Nashville, Tennessee 37232
- Department of Chemistry, Vanderbilt University Medical Center, Nashville, Tennessee 37232
- Vanderbilt Program in Drug Discovery, Vanderbilt University Medical Center, Nashville, Tennessee 37232
| | - P. Jeffrey Conn
- Department of Pharmacology, Vanderbilt University Medical Center, Nashville, Tennessee 37232
- Department of Chemistry, Vanderbilt University Medical Center, Nashville, Tennessee 37232
| | - James J. Lah
- Center for Neurodegenerative Disease and Department of Neurology, Emory University School of Medicine, Atlanta, Georgia 30322
| | - Allan I. Levey
- Center for Neurodegenerative Disease and Department of Neurology, Emory University School of Medicine, Atlanta, Georgia 30322
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Digby GJ, Shirey JK, Conn PJ. Allosteric activators of muscarinic receptors as novel approaches for treatment of CNS disorders. MOLECULAR BIOSYSTEMS 2010; 6:1345-54. [PMID: 20582339 PMCID: PMC4780333 DOI: 10.1039/c002938f] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Muscarinic acetylcholine receptors (mAChRs) represent exciting therapeutic targets for the treatment of multiple CNS disorders. The high degree of conservation of amino acids comprising the orthosteric acetylcholine (ACh) binding site between individual mAChR subtypes has hindered the development of subtype-selective compounds that bind to this site. As a result, many academic and industry researchers are now focusing on developing allosteric activators of mAChRs including both positive allosteric modulators (PAMs) and allosteric agonists. In the past 10 years major advances have been achieved in the discovery of allosteric ligands that possess much greater selectivity for individual mAChR subtypes when compared to previously developed orthosteric agents. These novel allosteric modulators of mAChRs may provide therapeutic potential for treatment of a number of CNS disorders such as Alzheimer's disease and schizophrenia.
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Affiliation(s)
- Gregory J. Digby
- 1215 Light Hall, 2215B Garland Ave., Nashville, TN 37237-0575, USA. ; Fax: +1 615 343 3088; Tel: +1 615 322 6730
| | - Jana K. Shirey
- 8410E Medical Research Building IV, 2215B Garland Ave., Nashville, TN 37237-0575, USA. ; Fax: +1 615 936-2661; Tel: +1 615 936-8424
| | - P. Jeffrey Conn
- 2215B Garland Ave., Nashville, TN 37237-0575, USA. ; Fax: +1 615 343 3088; Tel: +1 615 322 6730
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Abreu-Villaça Y, Filgueiras CC, Manhães AC. Developmental aspects of the cholinergic system. Behav Brain Res 2010; 221:367-78. [PMID: 20060019 DOI: 10.1016/j.bbr.2009.12.049] [Citation(s) in RCA: 111] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2009] [Accepted: 12/26/2009] [Indexed: 01/19/2023]
Abstract
Beyond its importance in sustaining or modulating different aspects of the activity of the central nervous system (CNS), the cholinergic system plays important roles during development. In the current review, we focus on the developmental aspects associated with major components of the cholinergic system: Acetylcholine, choline acetyltransferase, vesicular acetylcholine transporter, high-affinity choline transporter, acetylcholinesterase, nicotinic and muscarinic receptors. We describe when and where each one of these components is first identified in the CNS and the changes in their levels that occur during the course of prenatal and postnatal development. We also describe how these components are relevant to many events that occur during the development of the CNS, including progenitor cells proliferation and differentiation, neurogenesis, gliogenesis, neuronal maturation and plasticity, axonal pathfinding, regulation of gene expression and cell survival. It will be noticed that evidence regarding the developmental aspects of the cholinergic system comes mostly from studies that used agonists, such as nicotine, and antagonists, such as hemicholinium-3. Studies using immunohistochemistry and genetically altered mice also provided valuable information.
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Affiliation(s)
- Yael Abreu-Villaça
- Laboratório de Neurofisiologia, Departamento de Ciências Fisiológicas, Instituto de Biologia Roberto Alcantara Gomes, Centro Biomédico, Universidade do Estado do Rio de Janeiro, Av. Prof. Manoel de Abreu 444, 5 andar, Vila Isabel, Rio de Janeiro, RJ 20550-170, Brazil.
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Jin CH, Shin EJ, Park JB, Jang CG, Li Z, Kim MS, Koo KH, Yoon HJ, Park SJ, Choi WC, Yamada K, Nabeshima T, Kim HC. Fustin flavonoid attenuates β-amyloid (1-42)-induced learning impairment. J Neurosci Res 2009; 87:3658-70. [DOI: 10.1002/jnr.22159] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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AC-260584, an orally bioavailable M(1) muscarinic receptor allosteric agonist, improves cognitive performance in an animal model. Neuropharmacology 2009; 58:365-73. [PMID: 19835892 DOI: 10.1016/j.neuropharm.2009.10.003] [Citation(s) in RCA: 58] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2009] [Revised: 10/06/2009] [Accepted: 10/07/2009] [Indexed: 01/01/2023]
Abstract
The recent discovery of allosteric potentiators and agonists of the muscarinic M(1) receptor represents a significant advance in the muscarinic receptor pharmacology. In the current study we describe the receptor pharmacology and pro-cognitive action of the allosteric agonist AC-260584. Using in vitro cell-based assays with cell proliferation, phosphatidylinositol hydrolysis or calcium mobilization as endpoints, AC-260584 was found to be a potent (pEC(50) 7.6-7.7) and efficacious (90-98% of carbachol) muscarinic M(1) receptor agonist. Furthermore, as compared to orthosteric binding agonists, AC-260584 showed functional selectivity for the M(1) receptor over the M(2), M(3), M(4) and M(5) muscarinic receptor subtypes. Using GTPgammaS binding assays, its selectivity was found to be similar in native tissues expressing mAChRs to its profile in recombinant systems. In rodents, AC-260584 activated extracellular signal-regulated kinase 1 and 2 (ERK1/2) phosphorylation in the hippocampus, prefrontal cortex and perirhinal cortex. The ERK1/2 activation was dependent upon muscarinic M(1) receptor activation since it was not observed in M(1) knockout mice. AC-260584 also improved the cognitive performance of mice in the novel object recognition assay and its action is blocked by the muscarinic receptor antagonist pirenzepine. Taken together these results indicate for the first time that a M(1) receptor agonist selective over the other mAChR subtypes can have a symptomatically pro-cognitive action. In addition, AC-260584 was found to be orally bioavailable in rodents. Therefore, AC-260584 may serve as a lead compound in the development of M(1) selective drugs for the treatment of cognitive impairment associated with schizophrenia and Alzheimer's disease.
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Ravassard P, Pachoud B, Comte JC, Mejia-Perez C, Scoté-Blachon C, Gay N, Claustrat B, Touret M, Luppi PH, Salin PA. Paradoxical (REM) sleep deprivation causes a large and rapidly reversible decrease in long-term potentiation, synaptic transmission, glutamate receptor protein levels, and ERK/MAPK activation in the dorsal hippocampus. Sleep 2009; 32:227-40. [PMID: 19238810 DOI: 10.1093/sleep/32.2.227] [Citation(s) in RCA: 126] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
STUDY OBJECTIVES It has been shown that wake (W) and slow wave sleep (SWS) modulate synaptic transmission in neocortical projections. However the impact of paradoxical sleep (PS) quantities on synaptic transmission remains unknown. We examined whether PS modulated the excitatory transmission and expression of glutamate receptor subtypes and phosphorylated extracellular signal-regulated kinases (p-ERK1/2). DESIGN PS deprivation (PSD) was carried out with the multiple platforms method on adult male Sprague-Dawley rats. LTP, late-LTP, and synaptic transmission were studied in the dorsal and ventral hippocampus of controls, 75-h PSD and 150-min PS rebound (PSR). GluR1 and NR1 protein and mRNA expression were evaluated by western blot and real-time PCR. p-ERK1/2 level was quantified by western blot and immunohistochemistry. MEASUREMENT AND RESULTS PSD decreased synaptic transmission and LTP selectively in dorsal CA1 and PSR rescued these deficits. PSD-induced synaptic modifications in CA1 were associated with a decrease in GluR1, NR1, and p-ERK1/2 levels in dorsal CA1 without change in GluR1 and NR1 mRNA expression. Regression analysis shows that LTP is positively correlated with both PS quantities and SWS episodes duration, whereas synaptic transmission and late-LTP are positively correlated with PS quantities and negatively correlated with SWS quantities. CONCLUSIONS These findings unveil previously unrecognized roles of PSD on synaptic transmission and LTP in the dorsal, but not in the ventral, hippocampus. The fact that the decrease in protein expression of GluR1 and NR1 was not associated with a change in mRNA expression of these receptors suggests that a sleep-induced modulation of translational mechanisms occurs in dorsal CA1.
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Affiliation(s)
- Pascal Ravassard
- UMR 5167 CNRS, Physio-pathologie des reseaux neuronaux du cycle veille-sommeil, Institut Feddratifdes Neurosciences de Lyon (IFNL, IFR 19), Université Lyon, Lyon, France
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Moore SJ, Cooper DC, Spruston N. Plasticity of burst firing induced by synergistic activation of metabotropic glutamate and acetylcholine receptors. Neuron 2009; 61:287-300. [PMID: 19186170 DOI: 10.1016/j.neuron.2008.12.013] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2007] [Revised: 04/14/2008] [Accepted: 12/09/2008] [Indexed: 11/25/2022]
Abstract
Subiculum, the primary efferent pathway of hippocampus, participates in memory for spatial tasks, relapse to drug abuse, and temporal lobe seizures. Subicular pyramidal neurons exhibit low-threshold burst firing driven by a spike afterdepolarization. Here we report that burst firing can be regulated by stimulation of afferent projections to subiculum. Unlike synaptic plasticity, burst plasticity did not require synaptic depolarization, activation of AMPA or NMDA receptors, or action potential firing. Rather, enhancement of burst firing required synergistic activation of group I, subtype 1 metabotropic glutamate receptors (mGluRs) and muscarinic acetylcholine receptors (mAChR). When either of these receptors was blocked, a suppression of bursting was revealed, which in turn was blocked by antagonists of group I, subtype 5 mGluRs. These results indicate that the output of subiculum can be strongly and bidirectionally regulated by activation of glutamatergic inputs within the hippocampus and cholinergic afferents from the medial septum.
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Affiliation(s)
- Shannon J Moore
- Department of Neurobiology and Physiology, Northwestern University, 2205 Tech Drive, Evanston, IL 60208, USA
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45
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Luo L, Chen WH, Wang M, Zhu DM, She JQ, Ruan DY. Modulation of long-term potentiation by individual subtypes of muscarinic acetylcholine receptor in the rat dentate gyrus. Hippocampus 2008; 18:989-95. [PMID: 18548582 DOI: 10.1002/hipo.20461] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
The roles of the muscarinic acetylcholine (ACh) receptors (mAChRs) in long-term potentiation (LTP) at many areas of the central nervous system including the hippocampus, have been extensively studied. However, not much is known about the modulation of LTP through individual subtypes of mAChR (M(1)-M(5) subtype). In this study, we investigated the involvement of each individual subtypes of mAChR in LTP induction by intrahippocampal administration of cholinergic ligands at the dentate gyrus (DG) of anesthetized rats. We found atropine, an antagonist of mAChRs, suppressed the induction of LTP. This observation confirmed that the muscarinic system is involved in LTP. We then examined the effects of M(1)AChR antagonists (pirenzepine and telenzepine), M(2/4)AChR antagonists (Methoctramine and {11-[[2-[(diethylamino)methyl]-1-piperidinyl]acetyl]-5,11-dihydro-6H-pyrido[2,3-b][1,4]benzodiazepin-6-one}(AFDX-116)), and M(3/5)AChR antagonist (4-diphenylacetoxy-N-methylpiperidine methiodide (4-DAMP)) on LTP. Our results showed that both M(1)AChR and M(2/4)AChR antagonists but not M(3/5)AChR antagonist suppressed the amplitude of LTP. We also examined the effects of these cholinergic ligands on basal synaptic transmission and found that only pirenzepine augmented the amplitude of population spike. This study suggests that individual mAChR subtypes play different modulation roles in LTP induction in the DG of rats.
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Affiliation(s)
- Le Luo
- School of Life Sciences, University of Science and Technology of China, Hefei, Anhui, People's Republic of China 230027
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Kim SJ, Lee K. Extracts of Liriopsis tuber protect AMPA induced brain damage and improve memory with the activation of insulin receptor and ERK I/II. Phytother Res 2008; 22:1450-7. [PMID: 18803226 DOI: 10.1002/ptr.2475] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
The brain insulin receptor and ERK I/II are known to play an important role in memory formation and neuroprotection. A series of experiments was designed to explore if Liriopsis tuber (LT) extracts could exhibit neuroprotection and memory enhancing actions. LT was extracted with 70% methanol and subsequently fractionated into chloroform (fraction C), chloroform/methanol-(3:1) (fraction CM), methanol-soluble (fraction M) and methanol-insoluble, water-soluble fractions (fraction A). The LT fractions (T, C, M, A) significantly inhibited the cortical depolarization induced by AMPA in cortical slices of rats. In addition, these fractions were also effective in promoting memory in the passive avoidance test in mice. To gain insight into the mechanism of memory enhancing effects by Liriopsis tuber extracts, the activities of hippocampal insulin receptors and ERK I/II were tested in rats. Extract of LT (T) dramatically stimulated tyrosine phosphorylation of the insulin receptor, while fraction C of LT also significantly stimulated the same. In addition, ERK I/II were stimulated and cholinesterase activities were inhibited by fractions T, C, M and A in the rat hippocampus. These results suggest that Liriopsis tuber extracts may exert neuroprotection and memory enhancing effects via activation of the insulin receptor and ERK I/II as well as inhibiting cholinesterase.
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Affiliation(s)
- Sung-Jin Kim
- Department of Pharmacology, Metabolic Diseases Research Laboratory, School of Dentistry, Kyung Hee University, Seoul, Korea.
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Shor OL, Fidzinski P, Behr J. Muscarinic acetylcholine receptors and voltage-gated calcium channels contribute to bidirectional synaptic plasticity at CA1-subiculum synapses. Neurosci Lett 2008; 449:220-3. [PMID: 19010390 DOI: 10.1016/j.neulet.2008.11.012] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2008] [Revised: 11/05/2008] [Accepted: 11/06/2008] [Indexed: 11/30/2022]
Abstract
Hippocampal output is mediated via the subiculum, which is the principal target of CA1 pyramidal cells, and which sends projections to a variety of cortical and subcortical regions. Pyramidal cells in the subiculum display two different firing modes and are classified as being burst-spiking or regular-spiking. In a previous study, we found that low-frequency stimulation induces an NMDA receptor-dependent long-term depression (LTD) in burst-spiking cells and a metabotropic glutamate receptor-dependent long-term potentiation (LTP) in regular-spiking cells [P. Fidzinski, O. Shor, J. Behr, Target-cell-specific bidirectional synaptic plasticity at hippocampal output synapses, Eur. J. Neurosci., 27 (2008) 1111-1118]. Here, we present evidence that this bidirectional plasticity relies upon the co-activation of muscarinic acetylcholine receptors, as scopolamine blocks synaptic plasticity in both cell types. In addition, we demonstrate that the L-type calcium channel inhibitor nifedipine converts LTD to LTP in burst-spiking cells and LTP to LTD in regular-spiking cells, indicating that the polarity of synaptic plasticity is modulated by voltage-gated calcium channels. Bidirectional synaptic plasticity in subicular cells therefore appears to be governed by a complex signaling system, involving cell-specific recruitment of ligand and voltage-gated ion channels as well as metabotropic receptors. This complex regulation might be necessary for fine-tuning of synaptic efficacy at hippocampal output synapses.
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Affiliation(s)
- Oded Lipa Shor
- Department of Psychiatry and Psychotherapy, Charité Universitätsmedizin Berlin, Chariteplatz 1, 10117 Berlin, Germany
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Coactivation of M(1) muscarinic and alpha1 adrenergic receptors stimulates extracellular signal-regulated protein kinase and induces long-term depression at CA3-CA1 synapses in rat hippocampus. J Neurosci 2008; 28:5350-8. [PMID: 18480291 DOI: 10.1523/jneurosci.5058-06.2008] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Intact cholinergic innervation from the medial septum and noradrenergic innervation from the locus ceruleus are required for hippocampal-dependent learning and memory. However, much remains unclear about the precise roles of acetylcholine (ACh) and norepinephrine (NE) in hippocampal function, particularly in terms of how interactions between these two transmitter systems might play an important role in synaptic plasticity. Previously, we reported that activation of either muscarinic M(1) or adrenergic alpha1 receptors induces activity- and NMDA receptor-dependent long-term depression (LTD) at CA3-CA1 synapses in acute hippocampal slices, referred to as muscarinic LTD (mLTD) and norepinephrine LTD (NE LTD), respectively. In this study, we tested the hypothesis that mLTD and NE LTD are independent forms of LTD, yet require activation of a common Galphaq-coupled signaling pathway for their induction, and investigated the net effect of coactivation of M(1) and alpha1 receptors on the magnitude of LTD induced. We find that neither mLTD nor NE LTD requires phospholipase C activation, but both plasticities are prevented by inhibiting the Src kinase family and extracellular signal-regulated protein kinase (ERK) activation. Interestingly, LTD can be induced when M(1) and alpha1 agonists are coapplied at concentrations too low to induce LTD when applied separately, via a summed increase in ERK activation. Thus, because ACh and NE levels in vivo covary, especially during periods of memory encoding and consolidation, cooperative signaling through M(1) and alpha1 receptors could function to induce long-term changes in synaptic function important for cognition.
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Giovannini MG, Cerbai F, Bellucci A, Melani C, Grossi C, Bartolozzi C, Nosi D, Casamenti F. Differential activation of mitogen-activated protein kinase signalling pathways in the hippocampus of CRND8 transgenic mouse, a model of Alzheimer's disease. Neuroscience 2008; 153:618-33. [PMID: 18406062 DOI: 10.1016/j.neuroscience.2008.02.061] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2008] [Revised: 02/05/2008] [Accepted: 02/05/2008] [Indexed: 01/03/2023]
Abstract
Transgenic Centre for Research in Neurodegenerative Diseases 8 (TgCRND8) mice expressing a double mutant form of human amyloid precursor protein represent a good model of Alzheimer's disease, and can be useful to clarify the involvement of mitogen-activated protein kinases (MAPK) dysregulation in the pathophysiology of this neurodegenerative disorder. Activation of extracellular regulated kinase (ERK) 1/2, jun kinase (JNK) and p38MAPK was studied in the hippocampus of 7-month-old TgCRND8 mice by immunohistochemistry and Western blot analysis using antibodies selective for the phosphorylated, and thus active, forms of the enzymes. We demonstrated that the three main MAPK pathways were differentially activated in cells of the hippocampus of TgCRND8 mice in comparison to wild type (Wt) littermates, p38MAPK and JNK being more activated, while ERK less activated. p38MAPK was significantly activated in microglia, astrocytes and neurons, around and distant from the plaques. JNK was highly activated in cells closely surrounding the plaques. No difference was observed in the activation of the two major bands of JNK, at a molecular weight of 46 kDa and 54 kDa. These data indicate the possible involvement of p38MAPK and JNK pathways dysregulation in the pathogenesis of Alzheimer's disease. The ERK2 isoform of the ERK pathway was less activated in the hippocampal dentate gyrus of Tg mice in basal conditions. Furthermore activation of the ERK pathway by ex vivo cholinergic stimulation with carbachol caused significantly higher activation of ERK in the hippocampus of Wt mice than in Tg mice. These findings may pose a molecular basis for the memory disruption of Alzheimer's disease, since proper functioning of the basal forebrain cholinergic neurons and of ERK2 is critical for memory formation.
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Affiliation(s)
- M G Giovannini
- Dipartimento di Farmacologia, University of Florence, Florence, Italy.
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Salah-Uddin H, Thomas DR, Davies CH, Hagan JJ, Wood MD, Watson JM, Challiss RAJ. Pharmacological assessment of m1 muscarinic acetylcholine receptor-gq/11 protein coupling in membranes prepared from postmortem human brain tissue. J Pharmacol Exp Ther 2008; 325:869-74. [PMID: 18322150 DOI: 10.1124/jpet.108.137968] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Using a selective Galpha(q/11) protein antibody capture guanosine 5'-O-(3-[35S]thio)triphosphate ([35S]GTPgammaS) binding approach, it has been possible to perform a quantitative pharmacological examination of the functional activity of the M(1) muscarinic acetylcholine receptor (mAChR) in membranes prepared from human postmortem cerebral cortex. Oxotremorine-M caused a > or = 2-fold increase in [35S]GTPgammaS-Galpha(q/11) binding with a pEC(50) of 6.06 +/- 0.16 in Brodmann's areas 23 and 25 that was almost completely inhibited by preincubation of membranes with the M(1) mAChR subtype-selective antagonist muscarinic toxin-7. In addition, the orthosteric and allosteric agonists, xanomeline [3(3-hexyloxy-1,2,5-thiadiazol-4-yl)-1,2,5,6-tetrahydro-1-methylpyridine] and AC-42 (4-n-butyl-1-[4-(2-methylphenyl)-4-oxo-1-butyl]-piperidine hydrogen chloride), increased [35S]-GTPgammaS-Galpha(q/11) binding, but with reduced intrinsic activities, inducing maximal responses that were 42 +/- 1 and 44 +/- 2% of the oxotremorine-M-induced response, respectively. These data indicate that the M(1) receptor is the predominant mAChR subtype coupling to the Galpha(q/11) G protein in these brain regions and that it is possible to quantify the potency and intrinsic activity of full and partial M(1) mAChR receptor agonists in postmortem human brain using a selective Galpha(q/11) protein antibody capture [35S]GTPgammaS binding assay.
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Affiliation(s)
- Hasib Salah-Uddin
- Department of Cell Physiology and Pharmacology, University of Leicester, Henry Wellcome Building, Lancaster Road, Leicester LE1 9HN, United Kingdom
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