1
|
Zhang G, Diamante G, Ahn IS, Palafox-Sanchez V, Cheng J, Cheng M, Ying Z, Wang SSM, Abuhanna KD, Phi N, Arneson D, Cely I, Arellano K, Wang N, Gomez-Pinilla F, Yang X. Thyroid hormone T4 mitigates traumatic brain injury in mice by dynamically remodeling cell type specific genes, pathways, and networks in hippocampus and frontal cortex. Biochim Biophys Acta Mol Basis Dis 2024:167344. [PMID: 39004380 DOI: 10.1016/j.bbadis.2024.167344] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2024] [Revised: 05/30/2024] [Accepted: 07/05/2024] [Indexed: 07/16/2024]
Abstract
The complex pathology of mild traumatic brain injury (mTBI) is a main contributor to the difficulties in achieving a successful therapeutic regimen. Thyroxine (T4) administration has been shown to prevent the cognitive impairments induced by mTBI in mice but the mechanism is poorly understood. To understand the underlying mechanism, we carried out a single cell transcriptomic study to investigate the spatiotemporal effects of T4 on individual cell types in the hippocampus and frontal cortex at three post-injury stages in a mouse model of mTBI. We found that T4 treatment altered the proportions and transcriptomes of numerous cell types across tissues and timepoints, particularly oligodendrocytes, astrocytes, and microglia, which are crucial for injury repair. T4 also reversed the expression of mTBI-affected genes such as Ttr, mt-Rnr2, Ggn12, Malat1, Gnaq, and Myo3a, as well as numerous pathways such as cell/energy/iron metabolism, immune response, nervous system, and cytoskeleton-related pathways. Cell-type specific network modeling revealed that T4 mitigated select mTBI-perturbed dynamic shifts in subnetworks related to cell cycle, stress response, and RNA processing in oligodendrocytes. Cross cell-type ligand-receptor networks revealed the roles of App, Hmgb1, Fn1, and Tnf in mTBI, with the latter two ligands having been previously identified as TBI network hubs. mTBI and/or T4 signature genes were enriched for human genome-wide association study (GWAS) candidate genes for cognitive, psychiatric and neurodegenerative disorders related to mTBI. Our systems-level single cell analysis elucidated the temporal and spatial dynamic reprogramming of cell-type specific genes, pathways, and networks, as well as cell-cell communications as the mechanisms through which T4 mitigates cognitive dysfunction induced by mTBI.
Collapse
Affiliation(s)
- Guanglin Zhang
- Department of Integrative Biology and Physiology, University of California, Los Angeles, Los Angeles, CA 90095, USA
| | - Graciel Diamante
- Department of Integrative Biology and Physiology, University of California, Los Angeles, Los Angeles, CA 90095, USA
| | - In Sook Ahn
- Department of Integrative Biology and Physiology, University of California, Los Angeles, Los Angeles, CA 90095, USA
| | - Victoria Palafox-Sanchez
- Department of Integrative Biology and Physiology, University of California, Los Angeles, Los Angeles, CA 90095, USA
| | - Jenny Cheng
- Department of Integrative Biology and Physiology, University of California, Los Angeles, Los Angeles, CA 90095, USA; Molecular, Cellular and Integrative Physiology Interdepartmental Program, University of California, Los Angeles, Los Angeles, CA 90095, USA
| | - Michael Cheng
- Department of Integrative Biology and Physiology, University of California, Los Angeles, Los Angeles, CA 90095, USA; Bioinformatics Interdepartmental Program, University of California, Los Angeles, Los Angeles, CA 90095, USA
| | - Zhe Ying
- Department of Integrative Biology and Physiology, University of California, Los Angeles, Los Angeles, CA 90095, USA
| | - Susanna Sue-Ming Wang
- Department of Integrative Biology and Physiology, University of California, Los Angeles, Los Angeles, CA 90095, USA
| | - Kevin Daniel Abuhanna
- Department of Human Genetics, David Geffen School of Medicine at UCLA, Los Angeles, CA 90095, USA
| | - Nguyen Phi
- Department of Integrative Biology and Physiology, University of California, Los Angeles, Los Angeles, CA 90095, USA
| | - Douglas Arneson
- Department of Integrative Biology and Physiology, University of California, Los Angeles, Los Angeles, CA 90095, USA; Bioinformatics Interdepartmental Program, University of California, Los Angeles, Los Angeles, CA 90095, USA
| | - Ingrid Cely
- Department of Integrative Biology and Physiology, University of California, Los Angeles, Los Angeles, CA 90095, USA
| | - Kayla Arellano
- Department of Integrative Biology and Physiology, University of California, Los Angeles, Los Angeles, CA 90095, USA
| | - Ning Wang
- Department of Integrative Biology and Physiology, University of California, Los Angeles, Los Angeles, CA 90095, USA
| | - Fernando Gomez-Pinilla
- Department of Integrative Biology and Physiology, University of California, Los Angeles, Los Angeles, CA 90095, USA; Department of Neurosurgery, University of California, Los Angeles, Los Angeles, CA 90095, USA; Brain Injury Research Center, University of California, Los Angeles, Los Angeles, CA 90095, USA
| | - Xia Yang
- Department of Integrative Biology and Physiology, University of California, Los Angeles, Los Angeles, CA 90095, USA; Molecular, Cellular and Integrative Physiology Interdepartmental Program, University of California, Los Angeles, Los Angeles, CA 90095, USA; Bioinformatics Interdepartmental Program, University of California, Los Angeles, Los Angeles, CA 90095, USA; Institute for Quantitative and Computational Biosciences, University of California, Los Angeles, Los Angeles, CA 90095, USA; Molecular Biology Institute, University of California, Los Angeles, Los Angeles, CA 90095, USA; Brain Research Institute, University of California, Los Angeles, Los Angeles, CA 90095, USA; Department of Molecular and Medical Pharmacology, University of California, Los Angeles, Los Angeles, CA 90095, USA.
| |
Collapse
|
2
|
Goodwin AT, John AE, Joseph C, Habgood A, Tatler AL, Susztak K, Palmer M, Offermanns S, Henderson NC, Jenkins RG. Stretch regulates alveologenesis and homeostasis via mesenchymal Gαq/11-mediated TGFβ2 activation. Development 2023; 150:dev201046. [PMID: 37102682 PMCID: PMC10259661 DOI: 10.1242/dev.201046] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2022] [Accepted: 04/05/2023] [Indexed: 04/28/2023]
Abstract
Alveolar development and repair require tight spatiotemporal regulation of numerous signalling pathways that are influenced by chemical and mechanical stimuli. Mesenchymal cells play key roles in numerous developmental processes. Transforming growth factor-β (TGFβ) is essential for alveologenesis and lung repair, and the G protein α subunits Gαq and Gα11 (Gαq/11) transmit mechanical and chemical signals to activate TGFβ in epithelial cells. To understand the role of mesenchymal Gαq/11 in lung development, we generated constitutive (Pdgfrb-Cre+/-;Gnaqfl/fl;Gna11-/-) and inducible (Pdgfrb-Cre/ERT2+/-;Gnaqfl/fl;Gna11-/-) mesenchymal Gαq/11 deleted mice. Mice with constitutive Gαq/11 gene deletion exhibited abnormal alveolar development, with suppressed myofibroblast differentiation, altered mesenchymal cell synthetic function, and reduced lung TGFβ2 deposition, as well as kidney abnormalities. Tamoxifen-induced mesenchymal Gαq/11 gene deletion in adult mice resulted in emphysema associated with reduced TGFβ2 and elastin deposition. Cyclical mechanical stretch-induced TGFβ activation required Gαq/11 signalling and serine protease activity, but was independent of integrins, suggesting an isoform-specific role for TGFβ2 in this model. These data highlight a previously undescribed mechanism of cyclical stretch-induced Gαq/11-dependent TGFβ2 signalling in mesenchymal cells, which is imperative for normal alveologenesis and maintenance of lung homeostasis.
Collapse
Affiliation(s)
- Amanda T. Goodwin
- Centre for Respiratory Research, Translational Medical Sciences, School of Medicine, University of Nottingham, Nottingham, NG7 2RD, UK
- Respiratory Medicine, Nottingham NIHR Biomedical Research Centre, Nottingham, NG7 2RD, UK
- Respiratory Medicine, Biodiscovery Institute, University Park, University of Nottingham, Nottingham, NG7 2RD, UK
| | - Alison E. John
- Margaret Turner Warwick Centre for Fibrosing Lung Disease, National Heart and Lung Institute, Imperial College London, London, SW3 6LY, UK
| | - Chitra Joseph
- Centre for Respiratory Research, Translational Medical Sciences, School of Medicine, University of Nottingham, Nottingham, NG7 2RD, UK
- Respiratory Medicine, Nottingham NIHR Biomedical Research Centre, Nottingham, NG7 2RD, UK
- Respiratory Medicine, Biodiscovery Institute, University Park, University of Nottingham, Nottingham, NG7 2RD, UK
| | - Anthony Habgood
- Centre for Respiratory Research, Translational Medical Sciences, School of Medicine, University of Nottingham, Nottingham, NG7 2RD, UK
- Respiratory Medicine, Nottingham NIHR Biomedical Research Centre, Nottingham, NG7 2RD, UK
- Respiratory Medicine, Biodiscovery Institute, University Park, University of Nottingham, Nottingham, NG7 2RD, UK
| | - Amanda L. Tatler
- Centre for Respiratory Research, Translational Medical Sciences, School of Medicine, University of Nottingham, Nottingham, NG7 2RD, UK
- Respiratory Medicine, Nottingham NIHR Biomedical Research Centre, Nottingham, NG7 2RD, UK
- Respiratory Medicine, Biodiscovery Institute, University Park, University of Nottingham, Nottingham, NG7 2RD, UK
| | - Katalin Susztak
- Department of Medicine, Division of Nephrology, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA 19104, USA
| | - Matthew Palmer
- Department of Pathology, Division of Nephrology, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA 19104-4238, USA
| | - Stefan Offermanns
- Department of Pharmacology, Max Planck Institute for Heart and Lung Research, 61231 Bad Nauheim, Germany
| | - Neil C. Henderson
- Centre for Inflammation Research, University of Edinburgh, EH16 4TJ, UK
- MRC Human Genetics Unit, Institute of Genetics and Molecular Medicine, University of Edinburgh, Edinburgh, EH4 2XU, UK
| | - R. Gisli Jenkins
- Margaret Turner Warwick Centre for Fibrosing Lung Disease, National Heart and Lung Institute, Imperial College London, London, SW3 6LY, UK
| |
Collapse
|
3
|
2-AG-Mediated Control of GABAergic Signaling Is Impaired in a Model of Epilepsy. J Neurosci 2023; 43:571-583. [PMID: 36460464 PMCID: PMC9888507 DOI: 10.1523/jneurosci.0541-22.2022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2022] [Revised: 10/21/2022] [Accepted: 11/25/2022] [Indexed: 12/05/2022] Open
Abstract
Repeated seizures result in a persistent maladaptation of endocannabinoid (eCB) signaling, mediated part by anandamide signaling deficiency in the basolateral amygdala (BLA) that manifests as aberrant synaptic function and altered emotional behavior. Here, we determined the effect of repeated seizures (kindling) on 2-arachidonoylglycerol (2-AG) signaling on GABA transmission by directly measuring tonic and phasic eCB-mediated retrograde signaling in an in vitro BLA slice preparation from male rats. We report that both activity-dependent and muscarinic acetylcholine receptor (mAChR)-mediated depression of GABA synaptic transmission was reduced following repeated seizure activity. These effects were recapitulated in sham rats by preincubating slices with the 2-AG synthesizing enzyme inhibitor DO34. Conversely, preincubating slices with the 2-AG degrading enzyme inhibitor KML29 rescued activity-dependent 2-AG signaling, but not mAChR-mediated synaptic depression, over GABA transmission in kindled rats. These effects were not attributable to a change in cannabinoid type 1 (CB1) receptor sensitivity or altered 2-AG tonic signaling since the application of the highly selective CB1 receptor agonist CP55,940 provoked a similar reduction in GABA synaptic activity in both sham and kindled rats, while no effect of either DO34 or of the CB1 inverse agonist AM251 was observed on frequency and amplitude of spontaneous IPSCs in either sham or kindled rats. Collectively, these data provide evidence that repeated amygdala seizures persistently alter phasic 2-AG-mediated retrograde signaling at BLA GABAergic synapses, probably by impairing stimulus-dependent 2-AG synthesis/release, which contributes to the enduring aberrant synaptic plasticity associated with seizure activity.SIGNIFICANCE STATEMENT The plastic reorganization of endocannabinoid (eCB) signaling after seizures and during epileptogenesis may contribute to the negative neurobiological consequences associated with seizure activity. Therefore, a deeper understanding of the molecular basis underlying the pathologic long-term eCB signaling remodeling following seizure activity will be crucial to the development of novel therapies for epilepsy that not only target seizure activity, but, most importantly, the epileptogenesis and the comorbid conditions associated with epilepsy.
Collapse
|
4
|
Abstract
Motherhood goes through preparation, onset and maintenance phases until the natural weaning. A variety of changes in hormonal/neurohormonal systems and brain circuits are involved in the maternal behavior. Hormones, neuropeptides, and neurotransmitters involved in maternal behavior act via G-protein-coupled receptors, many of which in turn activate plasma membrane enzymes including phospholipase C (PLC) β isoforms. In this study, we examined the effect of PLCβ1 knockout (KO) on maternal behavior. There was little difference between PLCβ1-KO and wild-type (WT) dams in the relative time spent in maternal behavior during the period between 24 h prepartum and 12 h postpartum (-24 h ∼ PPH 12). After PPH 18, however, PLCβ1-KO dams neglected their pups so that they all died in 2-3 days. In the pup retrieval test, latency was not different during the period within PPH 12, but after PPH 18, PLCβ1-KO dams could not finish pup retrieval in a given time. During both periods, FosB expression in the nucleus accumbens (NAcc) of PLCβ1-KO dams was significantly lower than WT, but not different in the medial preoptic area (mPOA). Given that mPOA activity is required for initiation of maternal behavior, and that NAcc is known to be involved in maternal motivation and maintenance of maternal behavior, our results suggest that PLCβ1 signaling is essential for transition from the onset to maintenance phase of maternal behavior.
Collapse
Affiliation(s)
- Hea-jin Kim
- Brain Science Institute (BSI), Korea Institute of Science and Technology (KIST), Seoul, Republic of Korea,Division of Bio-Medical Science & Technology, KIST School, Korea University of Science and Technology (UST), Seoul, Republic of Korea
| | - Jaewon Jang
- Brain Science Institute (BSI), Korea Institute of Science and Technology (KIST), Seoul, Republic of Korea,Department of Life Sciences, Korea University, Seoul, Republic of Korea
| | - Hae-Young Koh
- Brain Science Institute (BSI), Korea Institute of Science and Technology (KIST), Seoul, Republic of Korea,Division of Bio-Medical Science & Technology, KIST School, Korea University of Science and Technology (UST), Seoul, Republic of Korea, Hae-Young Koh Brain Science Institute (BSI), Korea Institute of Science and Technology (KIST), Hwarang-ro 14-gil 5, Seongbuk-gu, Seoul, 02792, Republic of Korea
| |
Collapse
|
5
|
Bahceci D, Anderson LL, Kevin RC, Doohan PT, Arnold JC. Hyperthermia-Induced Seizures Enhance Brain Concentrations of the Endocannabinoid-Related Linoleoyl Glycerols in a Scn1a+/- Mouse Model of Dravet Syndrome. Cannabis Cannabinoid Res 2022. [PMID: 36269656 DOI: 10.1089/can.2022.0145] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Introduction: The endocannabinoid system contributes to the homeostatic response to seizure activity in epilepsy, a disease of brain hyperexcitability. Indeed, studies using conventional epilepsy models have shown that seizures increase endocannabinoids in the brain. However, it is unknown whether endocannabinoids and structurally related fatty acid amides and monoacylglycerols are similarly released in response to acute seizures in animal models of drug-resistant epilepsy. Therefore, in this study, we investigated whether a hyperthermia-induced seizure increased concentrations of endocannabinoids and related signaling lipids in the Scn1a+/- mouse model of Dravet syndrome. Materials and Methods: We compared hippocampal concentrations of the major endocannabinoids and related monoglycerols and N-acylethanolamines in wild-type mice, naïve Scn1a+/- mice, and Scn1a+/- mice primed with a single, hyperthermia-induced, generalized tonic-clonic seizure. Samples were collected 5 and 60 min following the seizure and then analyzed with LC-MS/MS. Results: We found that a hyperthermia-induced seizure in Scn1a+/- mice did not affect hippocampal concentrations of the major endocannabinoids, 2-AG and anandamide, or the N-acylethanolamines studied, although the sampling of tissue 5 min postseizure may have been too late to capture any effect on these lipids. Heterozygous deletion of Scn1a alone did not affect these lipid signaling molecules. Notably, however, we found that a hyperthermia-induced seizure significantly increased hippocampal concentrations of the monoacylglycerols, 2-linoleoyl glycerol (2-LG) and 1-linoleoyl glycerol (1-LG), in Scn1a+/- mice. Conclusions: Our results show the unprecedented elevation of the lesser-studied endocannabinoid-related monoacylglycerols, 2-LG and 1-LG, following a hyperthermia-induced seizure in a mouse model of Dravet syndrome. Future research is needed to comprehensively explore the function of these lipid signaling molecules during seizure activity and whether their actions can be exploited to develop new therapeutics.
Collapse
Affiliation(s)
- Dilara Bahceci
- Lambert Initiative for Cannabinoid Therapeutics, The University of Sydney, Camperdown , Australia.,Discipline of Pharmacology, School of Pharmacy, Faculty of Medicine and Health, The University of Sydney, Camperdown, Australia.,Brain and Mind Centre, The University of Sydney, Camperdown, Australia
| | - Lyndsey L Anderson
- Lambert Initiative for Cannabinoid Therapeutics, The University of Sydney, Camperdown , Australia.,Discipline of Pharmacology, School of Pharmacy, Faculty of Medicine and Health, The University of Sydney, Camperdown, Australia.,Brain and Mind Centre, The University of Sydney, Camperdown, Australia
| | - Richard C Kevin
- Lambert Initiative for Cannabinoid Therapeutics, The University of Sydney, Camperdown , Australia.,Discipline of Pharmacology, School of Pharmacy, Faculty of Medicine and Health, The University of Sydney, Camperdown, Australia.,Brain and Mind Centre, The University of Sydney, Camperdown, Australia
| | - Peter T Doohan
- Lambert Initiative for Cannabinoid Therapeutics, The University of Sydney, Camperdown , Australia.,Discipline of Pharmacology, School of Pharmacy, Faculty of Medicine and Health, The University of Sydney, Camperdown, Australia.,Brain and Mind Centre, The University of Sydney, Camperdown, Australia
| | - Jonathon C Arnold
- Lambert Initiative for Cannabinoid Therapeutics, The University of Sydney, Camperdown , Australia.,Discipline of Pharmacology, School of Pharmacy, Faculty of Medicine and Health, The University of Sydney, Camperdown, Australia.,Brain and Mind Centre, The University of Sydney, Camperdown, Australia
| |
Collapse
|
6
|
Dhakal P, Chaudhry SI, Signorelli R, Collins KM. Serotonin signals through postsynaptic Gαq, Trio RhoGEF, and diacylglycerol to promote Caenorhabditis elegans egg-laying circuit activity and behavior. Genetics 2022; 221:iyac084. [PMID: 35579369 PMCID: PMC9252285 DOI: 10.1093/genetics/iyac084] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2022] [Accepted: 04/26/2022] [Indexed: 11/12/2022] Open
Abstract
Activated Gαq signals through phospholipase-Cβ and Trio, a Rho GTPase exchange factor (RhoGEF), but how these distinct effector pathways promote cellular responses to neurotransmitters like serotonin remains poorly understood. We used the egg-laying behavior circuit of Caenorhabditis elegans to determine whether phospholipase-Cβ and Trio mediate serotonin and Gαq signaling through independent or related biochemical pathways. Our genetic rescue experiments suggest that phospholipase-Cβ functions in neurons while Trio Rho GTPase exchange factor functions in both neurons and the postsynaptic vulval muscles. While Gαq, phospholipase-Cβ, and Trio Rho GTPase exchange factor mutants fail to lay eggs in response to serotonin, optogenetic stimulation of the serotonin-releasing HSN neurons restores egg laying only in phospholipase-Cβ mutants. Phospholipase-Cβ mutants showed vulval muscle Ca2+ transients while strong Gαq and Trio Rho GTPase exchange factor mutants had little or no vulval muscle Ca2+ activity. Treatment with phorbol 12-myristate 13-acetate that mimics 1,2-diacylglycerol, a product of PIP2 hydrolysis, rescued egg-laying circuit activity and behavior defects of Gαq signaling mutants, suggesting both phospholipase-C and Rho signaling promote synaptic transmission and egg laying via modulation of 1,2-diacylglycerol levels. 1,2-Diacylglycerol activates effectors including UNC-13; however, we find that phorbol esters, but not serotonin, stimulate egg laying in unc-13 and phospholipase-Cβ mutants. These results support a model where serotonin signaling through Gαq, phospholipase-Cβ, and UNC-13 promotes neurotransmitter release, and that serotonin also signals through Gαq, Trio Rho GTPase exchange factor, and an unidentified, phorbol 12-myristate 13-acetate-responsive effector to promote postsynaptic muscle excitability. Thus, the same neuromodulator serotonin can signal in distinct cells and effector pathways to coordinate activation of a motor behavior circuit.
Collapse
Affiliation(s)
- Pravat Dhakal
- Department of Biology, University of Miami, Coral Gables, FL 33146, USA
| | - Sana I Chaudhry
- Department of Biology, University of Miami, Coral Gables, FL 33146, USA
| | | | - Kevin M Collins
- Department of Biology, University of Miami, Coral Gables, FL 33146, USA
| |
Collapse
|
7
|
Ghasemi Z, Naderi N, Shojaei A, Raoufy MR, Ahmadirad N, Barkley V, Mirnajafi-Zadeh J. Group I metabotropic glutamate receptors contribute to the antiepileptic effect of electrical stimulation in hippocampal CA1 pyramidal neurons. Epilepsy Res 2021; 178:106821. [PMID: 34839145 DOI: 10.1016/j.eplepsyres.2021.106821] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2021] [Revised: 11/04/2021] [Accepted: 11/16/2021] [Indexed: 11/17/2022]
Abstract
Low-frequency deep brain stimulation (LFS) inhibits neuronal hyperexcitability during epilepsy. Accordingly, the use of LFS as a treatment method for patients with drug-resistant epilepsy has been proposed. However, the LFS antiepileptic mechanisms are not fully understood. Here, the role of metabotropic glutamate receptors group I (mGluR I) in LFS inhibitory action on epileptiform activity (EA) was investigated. EA was induced by increasing the K+ concentration in artificial cerebrospinal fluid (ACSF) up to 12 mM in hippocampal slices of male Wistar rats. LFS (1 Hz, 900 pulses) was delivered to the bundles of Schaffer collaterals at the beginning of EA. The excitability of CA1 pyramidal neurons was assayed by intracellular whole-cell recording. Applying LFS reduced the firing frequency during EA and substantially moved the membrane potential toward repolarization after a high-K+ ACSF washout. In addition, LFS attenuated the EA-generated neuronal hyperexcitability. A blockade of both mGluR 1 and mGluR 5 prevented the inhibitory action of LFS on EA-generated neuronal hyperexcitability. Activation of mGluR I mimicked the LFS effects and had similar inhibitory action on excitability of CA1 pyramidal neurons following EA. However, mGluR I agonist's antiepileptic action was not as strong as LFS. The observed LFS effects were significantly attenuated in the presence of a PKC inhibitor. Altogether, the LFS' inhibitory action on neuronal hyperexcitability following EA relies, in part, on the activity of mGluR I and a PKC-related signaling pathway.
Collapse
Affiliation(s)
- Zahra Ghasemi
- Department of Physiology, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran; Lunenfeld-Tanenbaum Research Institute, Mount Sinai Hospital, Toronto, Canada
| | - Nima Naderi
- Department of Pharmacology and Toxicology, School of Pharmacy, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Amir Shojaei
- Department of Physiology, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran
| | - Mohammad Reza Raoufy
- Department of Physiology, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran
| | - Nooshin Ahmadirad
- Department of Physiology, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran
| | - Victoria Barkley
- Krembil Research Institute, University Health Network, Toronto, Canada
| | - Javad Mirnajafi-Zadeh
- Department of Physiology, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran; Institute for Brain Sciences and Cognition, Tarbiat Modares University, Tehran, Iran.
| |
Collapse
|
8
|
Estrada JA, Contreras I. Endocannabinoid Receptors in the CNS: Potential Drug Targets for the Prevention and Treatment of Neurologic and Psychiatric Disorders. Curr Neuropharmacol 2021; 18:769-787. [PMID: 32065105 PMCID: PMC7536826 DOI: 10.2174/1570159x18666200217140255] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2019] [Revised: 12/14/2019] [Accepted: 02/11/2020] [Indexed: 12/15/2022] Open
Abstract
The endocannabinoid system participates in the regulation of CNS homeostasis and functions, including neurotransmission, cell signaling, inflammation and oxidative stress, as well as neuronal and glial cell proliferation, differentiation, migration and survival. Endocannabinoids are produced by multiple cell types within the CNS and their main receptors, CB1 and CB2, are expressed in both neurons and glia. Signaling through these receptors is implicated in the modulation of neuronal and glial alterations in neuroinflammatory, neurodegenerative and psychiatric conditions, including Alzheimer’s, Parkinson’s and Huntington’s disease, multiple sclerosis, amyotrophic lateral sclerosis, stroke, epilepsy, anxiety and depression. The therapeutic potential of endocannabinoid receptors in neurological disease has been hindered by unwelcome side effects of current drugs used to target them; however, due to their extensive expression within the CNS and their involvement in physiological and pathological process in nervous tissue, they are attractive targets for drug development. The present review highlights the potential applications of the endocannabinoid system for the prevention and treatment of neurologic and psychiatric disorders.
Collapse
Affiliation(s)
- José Antonio Estrada
- Neurochemistry Laboratory, Faculty of Medicine, Universidad Autónoma del Estado de México, Toluca, Mexico
| | - Irazú Contreras
- Neurochemistry Laboratory, Faculty of Medicine, Universidad Autónoma del Estado de México, Toluca, Mexico
| |
Collapse
|
9
|
Haj-Mirzaian A, Ramezanzadeh K, Afshari K, Mousapour P, Abbasi N, Haj-Mirzaian A, Nikbakhsh R, Haddadi NS, Dehpour AR. Activation of ATP-sensitive K-channel promotes the anticonvulsant properties of cannabinoid receptor agonist through mitochondrial ATP level reduction. Epilepsy Behav 2019; 93:1-6. [PMID: 30776677 DOI: 10.1016/j.yebeh.2019.01.025] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/27/2018] [Revised: 12/27/2018] [Accepted: 01/17/2019] [Indexed: 11/15/2022]
Abstract
Cannabinoid receptor (CBR) agonist could act as a protective agent against seizure susceptibility in animal models of epilepsy. Studies have shown that potassium channels could play a key role in ameliorating neuronal excitability. In this study, we attempted to evaluate how CBRs and Adenosine Tri-Phosphate (ATP)-sensitive potassium channels collaborate to affect seizure susceptibility by changing the clonic seizure threshold (CST). We used male Naval Medical Research Institute (NMRI) mice and treated them with the following drugs: cromakalim (a potassium channel opener, 10 μg/kg), glibenclamide (a potassium channel blocker, 0.03 and 1 mg/kg), 0.5 mg/kg of AM-251 (a selective CB1 antagonist), AM-630 (a selective CB2 antagonist), and 0.5, 3, and 10 mg/kg of WIN 55,212-2 (a nonselective agonist of CBRs); and CST was appraised after each type of administration. Also, we evaluated the ATP level of the hippocampus in each treatment to clarify the interaction between the cannabinoid system and potassium channel. Our results showed that administration of WIN 55,212-2 at 10 mg/kg significantly increased CST (P < 0.001). This change could be reversed by using AM-251(P < 0.001) but not AM-630. Also, either cromakalim (10 μg/kg) or glibenclamide (0.03 and 1 mg/kg) could not significantly affect the CST. In addition, glibenclamide (1 mg/kg) could reverse the anticonvulsant effect of WIN 55,212-2 (10 mg/kg) on CST (P < 0.001). However, the anticonvulsant effect was observed when cromakalim (10 μg/kg) was added to WIN 55,212-2 at its subeffective dose (3 mg/kg) in comparison to single-treated animals. Interestingly, we observed that CB1 agonist could significantly decrease ATP level. In conclusion, CB1 agonist accomplishes at least a part of its anticonvulsant actions through ATP-sensitive potassium channels, probably by decreasing the mitochondrial ATP level to open the potassium channel to induce its anticonvulsant effect.
Collapse
Affiliation(s)
- Arvin Haj-Mirzaian
- Brain and Spinal Cord Injury Research Center, Neuroscience Institute, Tehran University of Medical Sciences, Tehran, Iran; Experimental Medicine Research Center, Tehran University of Medical Sciences, Tehran, Iran; Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Kiana Ramezanzadeh
- Brain and Spinal Cord Injury Research Center, Neuroscience Institute, Tehran University of Medical Sciences, Tehran, Iran; Experimental Medicine Research Center, Tehran University of Medical Sciences, Tehran, Iran; Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Khashayar Afshari
- Brain and Spinal Cord Injury Research Center, Neuroscience Institute, Tehran University of Medical Sciences, Tehran, Iran; Experimental Medicine Research Center, Tehran University of Medical Sciences, Tehran, Iran
| | - Pouria Mousapour
- Brain and Spinal Cord Injury Research Center, Neuroscience Institute, Tehran University of Medical Sciences, Tehran, Iran; Experimental Medicine Research Center, Tehran University of Medical Sciences, Tehran, Iran; Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Nooshin Abbasi
- Brain and Spinal Cord Injury Research Center, Neuroscience Institute, Tehran University of Medical Sciences, Tehran, Iran; Experimental Medicine Research Center, Tehran University of Medical Sciences, Tehran, Iran; Interdisciplinary Neuroscience Research Program (INRP), Tehran University of Medical Sciences (TUMS), Tehran, Iran
| | - Arya Haj-Mirzaian
- Brain and Spinal Cord Injury Research Center, Neuroscience Institute, Tehran University of Medical Sciences, Tehran, Iran; Experimental Medicine Research Center, Tehran University of Medical Sciences, Tehran, Iran; Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Rajan Nikbakhsh
- Brain and Spinal Cord Injury Research Center, Neuroscience Institute, Tehran University of Medical Sciences, Tehran, Iran; Experimental Medicine Research Center, Tehran University of Medical Sciences, Tehran, Iran; Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Nazgol-Sadat Haddadi
- Brain and Spinal Cord Injury Research Center, Neuroscience Institute, Tehran University of Medical Sciences, Tehran, Iran; Experimental Medicine Research Center, Tehran University of Medical Sciences, Tehran, Iran
| | - Ahmad Reza Dehpour
- Brain and Spinal Cord Injury Research Center, Neuroscience Institute, Tehran University of Medical Sciences, Tehran, Iran; Experimental Medicine Research Center, Tehran University of Medical Sciences, Tehran, Iran.
| |
Collapse
|
10
|
Gorzkiewicz A, Szemraj J. Brain endocannabinoid signaling exhibits remarkable complexity. Brain Res Bull 2018; 142:33-46. [PMID: 29953913 DOI: 10.1016/j.brainresbull.2018.06.012] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2018] [Revised: 06/06/2018] [Accepted: 06/21/2018] [Indexed: 01/04/2023]
Abstract
The endocannabinoid (eCB) signaling system is one of the most extensive of the mammalian brain. Despite the involvement of only few specific ligands and receptors, the system encompasses a vast diversity of triggered mechanisms and driven effects. It mediates a wide range of phenomena, including the regulation of transmitter release, neural excitability, synaptic plasticity, impulse spread, long-term neuronal potentiation, neurogenesis, cell death, lineage segregation, cell migration, inflammation, oxidative stress, nociception and the sleep cycle. It is also known to be involved in the processes of learning and memory formation. This extensive scope of action is attained by combining numerous variables. In a properly functioning brain, the correlations of these variables are kept in a strictly controlled balance; however, this balance is disrupted in many pathological conditions. However, while this balance is known to be disrupted by drugs in the case of addicts, the stimuli and mechanisms influencing the neurodegenerating brain remain elusive. This review examines the multiple factors and phenomena affecting the eCB signaling system in the brain. It evaluates techniques of controlling the eCB system to identify the obstacles in their applications and highlights the crucial interdependent variables that may influence biomedical research outcomes.
Collapse
Affiliation(s)
- Anna Gorzkiewicz
- Medical University of Lodz, ul.Mazowiecka 6/8, 92-215, Lodz, Poland.
| | - Janusz Szemraj
- Medical University of Lodz, ul.Mazowiecka 6/8, 92-215, Lodz, Poland
| |
Collapse
|
11
|
Fatty acid amide hydrolase inhibitor URB597 may protect against kainic acid-induced damage to hippocampal neurons: Dependence on the degree of injury. Epilepsy Res 2017; 137:84-94. [PMID: 28963903 DOI: 10.1016/j.eplepsyres.2017.09.017] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2017] [Revised: 08/22/2017] [Accepted: 09/21/2017] [Indexed: 01/24/2023]
Abstract
OBJECTIVE Status epilepticus (SE) provokes changes, which lead to neuronal alterations. Endocannabinoids (eCBs) can affect the neuronal survival during excitotoxicity and brain damage. Using a kainic acid (KA)-induced experimental SE model, we investigated whether cellular changes entail damage to endoplasmic reticulum (ER), mitochondria, and nuclei in hippocampal cells (CA1 field), and whether these alterations can be diminished by treatment with URB597, an inhibitor of eCB enzymatic degradation. MATERIAL AND METHODS SE was induced in Wistar rats by the microinjection of KA into the lateral ventricle. URB597 or a vehicle (10% DMSO) were injected in the same way into the brain of animals 24h after the KA infusion and then daily for the next nine days. The behavior of animals was controlled visually and recorded with a video system. The intensity of SE significantly varied in different animals. Convulsive (stages 3-5 according to the Racine scale) and nonconvulsive seizures (mainly stages 1, 2 and rarely 3, 4) were recognized. RESULTS Two weeks after SE, a significant loss of hippocampal cells occurred in animals with KA injections. In survived cells, ultrastructural alterations in ER, mitochondria, and nuclei of hippocampal neurons were observed. The degree of cell injury depended on the severity of SE. Alterations evoked by moderate seizures were prevented or diminished by URB597, but strong seizures induced mostly irreversible damage. CONCLUSIONS The beneficial impact of the FAAH inhibitor URB597 can give impetus to the development of novel neuroprotective strategies.
Collapse
|
12
|
Shubina L, Aliev R, Kitchigina V. Endocannabinoid-dependent protection against kainic acid-induced long-term alteration of brain oscillations in guinea pigs. Brain Res 2017; 1661:1-14. [DOI: 10.1016/j.brainres.2017.02.003] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2016] [Revised: 02/02/2017] [Accepted: 02/03/2017] [Indexed: 01/12/2023]
|
13
|
Perescis MFJ, de Bruin N, Heijink L, Kruse C, Vinogradova L, Lüttjohann A, van Luijtelaar G, van Rijn CM. Cannabinoid antagonist SLV326 induces convulsive seizures and changes in the interictal EEG in rats. PLoS One 2017; 12:e0165363. [PMID: 28151935 PMCID: PMC5289424 DOI: 10.1371/journal.pone.0165363] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2016] [Accepted: 10/11/2016] [Indexed: 11/18/2022] Open
Abstract
Cannabinoid CB1 antagonists have been investigated for possible treatment of e.g. obesity-related disorders. However, clinical application was halted due to their symptoms of anxiety and depression. In addition to these adverse effects, we have shown earlier that chronic treatment with the CB1 antagonist rimonabant may induce EEG-confirmed convulsive seizures. In a regulatory repeat-dose toxicity study violent episodes of “muscle spasms” were observed in Wistar rats, daily dosed with the CB1 receptor antagonist SLV326 during 5 months. The aim of the present follow-up study was to investigate whether these violent movements were of an epileptic origin. In selected SLV326-treated and control animals, EEG and behavior were monitored for 24 hours. 25% of SLV326 treated animals showed 1 to 21 EEG-confirmed generalized convulsive seizures, whereas controls were seizure-free. The behavioral seizures were typical for a limbic origin. Moreover, interictal spikes were found in 38% of treated animals. The frequency spectrum of the interictal EEG of the treated rats showed a lower theta peak frequency, as well as lower gamma power compared to the controls. These frequency changes were state-dependent: they were only found during high locomotor activity. It is concluded that long term blockade of the endogenous cannabinoid system can provoke limbic seizures in otherwise healthy rats. Additionally, SLV326 alters the frequency spectrum of the EEG when rats are highly active, suggesting effects on complex behavior and cognition.
Collapse
Affiliation(s)
- Martin F. J. Perescis
- Donders Institute for Brain, Cognition and Behaviour, Radboud University, Nijmegen, The Netherlands
- HAS University of Applied Sciences, ‘s-Hertogenbosch, The Netherlands
- * E-mail:
| | - Natasja de Bruin
- Abbott Healthcare Products BV (formerly Solvay Pharmaceuticals), Weesp, The Netherlands
| | - Liesbeth Heijink
- Abbott Healthcare Products BV (formerly Solvay Pharmaceuticals), Weesp, The Netherlands
| | - Chris Kruse
- Abbott Healthcare Products BV (formerly Solvay Pharmaceuticals), Weesp, The Netherlands
| | - Lyudmila Vinogradova
- Institute of Higher Nervous Activity and Neurophysiology, Russian Academy of Sciences, Moscow, Russia
| | - Annika Lüttjohann
- Institut für Physiologie I, Westfälische Wilhelms Universität Münster, Münster, Germany
| | - Gilles van Luijtelaar
- Donders Institute for Brain, Cognition and Behaviour, Radboud University, Nijmegen, The Netherlands
| | - Clementina M. van Rijn
- Donders Institute for Brain, Cognition and Behaviour, Radboud University, Nijmegen, The Netherlands
| |
Collapse
|
14
|
Reim T, Balfanz S, Baumann A, Blenau W, Thamm M, Scheiner R. AmTAR2: Functional characterization of a honeybee tyramine receptor stimulating adenylyl cyclase activity. INSECT BIOCHEMISTRY AND MOLECULAR BIOLOGY 2017; 80:91-100. [PMID: 27939988 DOI: 10.1016/j.ibmb.2016.12.004] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/20/2016] [Revised: 12/02/2016] [Accepted: 12/06/2016] [Indexed: 06/06/2023]
Abstract
The biogenic monoamines norepinephrine and epinephrine regulate important physiological functions in vertebrates. Insects such as honeybees do not synthesize these neuroactive substances. Instead, they employ octopamine and tyramine for comparable physiological functions. These biogenic amines activate specific guanine nucleotide-binding (G) protein-coupled receptors (GPCRs). Based on pharmacological data obtained on heterologously expressed receptors, α- and β-adrenergic-like octopamine receptors are better activated by octopamine than by tyramine. Conversely, GPCRs forming the type 1 tyramine receptor clade (synonymous to octopamine/tyramine receptors) are better activated by tyramine than by octopamine. More recently, receptors were characterized which are almost exclusively activated by tyramine, thus forming an independent type 2 tyramine receptor clade. Functionally, type 1 tyramine receptors inhibit adenylyl cyclase activity, leading to a decrease in intracellular cAMP concentration ([cAMP]i). Type 2 tyramine receptors can mediate Ca2+ signals or both Ca2+ signals and effects on [cAMP]i. We here provide evidence that the honeybee tyramine receptor 2 (AmTAR2), when heterologously expressed in flpTM cells, exclusively causes an increase in [cAMP]i. The receptor displays a pronounced preference for tyramine over octopamine. Its activity can be blocked by a series of established antagonists, of which mianserin and yohimbine are most efficient. The functional characterization of two tyramine receptors from the honeybee, AmTAR1 (previously named AmTYR1) and AmTAR2, which respond to tyramine by changing cAMP levels in opposite direction, is an important step towards understanding the actions of tyramine in honeybee behavior and physiology, particularly in comparison to the effects of octopamine.
Collapse
Affiliation(s)
- Tina Reim
- Institute of Biochemistry and Biology, University of Potsdam, Potsdam, Germany
| | - Sabine Balfanz
- Institute of Complex Systems, ICS-4, Forschungszentrum Jülich, Jülich, Germany
| | - Arnd Baumann
- Institute of Complex Systems, ICS-4, Forschungszentrum Jülich, Jülich, Germany
| | - Wolfgang Blenau
- Zoological Institute, University of Cologne, Cologne, Germany
| | - Markus Thamm
- Institute of Biochemistry and Biology, University of Potsdam, Potsdam, Germany; Behavioral Physiology and Sociobiology (Zoology II), Biocenter, University of Würzburg, Würzburg, Germany
| | - Ricarda Scheiner
- Institute of Biochemistry and Biology, University of Potsdam, Potsdam, Germany; Behavioral Physiology and Sociobiology (Zoology II), Biocenter, University of Würzburg, Würzburg, Germany.
| |
Collapse
|
15
|
Huang J, Liu W, Qi YX, Luo J, Montell C. Neuromodulation of Courtship Drive through Tyramine-Responsive Neurons in the Drosophila Brain. Curr Biol 2016; 26:2246-56. [PMID: 27498566 DOI: 10.1016/j.cub.2016.06.061] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2016] [Revised: 06/02/2016] [Accepted: 06/27/2016] [Indexed: 01/12/2023]
Abstract
Neuromodulators influence the activities of collections of neurons and have profound impacts on animal behavior. Male courtship drive is complex and subject to neuromodulatory control. Using the fruit fly Drosophila melanogaster, we identified neurons in the brain (inferior posterior slope; IPS) that impact courtship drive and were controlled by tyramine-a biogenic amine related to dopamine, whose roles in most animals are enigmatic. We knocked out a tyramine-specific receptor, TyrR, which was expressed in IPS neurons. Loss of TyrR led to a striking elevation in courtship activity between males. This effect occurred only in the absence of females, as TyrR(Gal4) mutant males exhibited a wild-type preference for females. Artificial hyperactivation of IPS neurons caused a large increase in male-male courtship, whereas suppression of IPS activity decreased male-female courtship. We conclude that TyrR is a receptor for tyramine, and suggest that it serves to curb high levels of courtship activity through functioning as an inhibitory neuromodulator.
Collapse
Affiliation(s)
- Jia Huang
- Institute of Insect Sciences, Zhejiang University, Hangzhou 310058, China; Neuroscience Research Institute and Department of Molecular, Cellular and Developmental Biology, University of California, Santa Barbara, Santa Barbara, CA 93106, USA.
| | - Weiwei Liu
- Neuroscience Research Institute and Department of Molecular, Cellular and Developmental Biology, University of California, Santa Barbara, Santa Barbara, CA 93106, USA
| | - Yi-Xiang Qi
- Institute of Insect Sciences, Zhejiang University, Hangzhou 310058, China
| | - Junjie Luo
- Neuroscience Research Institute and Department of Molecular, Cellular and Developmental Biology, University of California, Santa Barbara, Santa Barbara, CA 93106, USA; The Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Craig Montell
- Neuroscience Research Institute and Department of Molecular, Cellular and Developmental Biology, University of California, Santa Barbara, Santa Barbara, CA 93106, USA.
| |
Collapse
|
16
|
Wang X, Wang Y, Zhang C, Liu C, Zhao B, Wei N, Zhang JG, Zhang K. CB1 receptor antagonism prevents long-term hyperexcitability after head injury by regulation of dynorphin-KOR system and mGluR5 in rat hippocampus. Brain Res 2016; 1646:174-181. [PMID: 27262683 DOI: 10.1016/j.brainres.2016.05.055] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2015] [Revised: 05/28/2016] [Accepted: 05/31/2016] [Indexed: 01/23/2023]
Abstract
Both endocannabinoids and dynorphin are feedback messengers in nervous system that act at the presynaptic nerve terminal to inhibit transmitter release. Many studies showed the cannabinoid-opioid cross-modulation in antinociception, hypothermia, sedation and reward. The aim of this study was to assess the influence of early application of cannabinoid type 1 (CB1) receptor antagonism SR141716A after brain injury on dynorphin-κ opioid receptor (KOR) system and the expression of metabotropic glutamate receptors (mGluRs) in a rat model of fluid percussion injury (FPI). Firstly, seizure latency induced by pentylenetetrazole was significantly prolonged 6 weeks after brain injury in group of SR141716A treatment. Then, PCR and western blot showed that SR141716A inhibited the long-term up-regulation of CB1 receptors in hippocampus. However, SR141716A resulted in long-term potentiation of dynorphin release and did not influence the up-regulation of KOR in hippocampus after brain injury. Furthermore, SR141716A reverse the overexpression of mGluR5 in the late stage of brain injury. We propose that during the induction of epileptogenesis after brain injury, early application of CB1 receptor antagonism could prevent long-term hyperexcitability by up-regulation of dynorphin-KOR system and prevention of mGluR5 induced epileptogenesis in hippocampus.
Collapse
Affiliation(s)
- Xiu Wang
- Department of Neurosurgery, Beijing Tiantan Hospital, Capital Medical University, Tiantan xili 6, Dongcheng, Beijing 100050, China; Beijing Key Laboratory of Neurostimulation, Tiantan xili 6, Dongcheng, Beijing 100050, China
| | - Yao Wang
- Beijing Jingmei Group General Hospital, Heishan Street 18, Mentougou, Beijing 102300, China
| | - Chao Zhang
- Department of Neurosurgery, Beijing Tiantan Hospital, Capital Medical University, Tiantan xili 6, Dongcheng, Beijing 100050, China; Beijing Key Laboratory of Neurostimulation, Tiantan xili 6, Dongcheng, Beijing 100050, China
| | - Chang Liu
- Department of Neurosurgery, Beijing Tiantan Hospital, Capital Medical University, Tiantan xili 6, Dongcheng, Beijing 100050, China; Beijing Key Laboratory of Neurostimulation, Tiantan xili 6, Dongcheng, Beijing 100050, China
| | - Baotian Zhao
- Department of Neurosurgery, Beijing Tiantan Hospital, Capital Medical University, Tiantan xili 6, Dongcheng, Beijing 100050, China; Beijing Key Laboratory of Neurostimulation, Tiantan xili 6, Dongcheng, Beijing 100050, China
| | - Naili Wei
- Department of Neurosurgery, The Second Hospital of Lanzhou University, Chengguan District, Lanzhou, Gansu 730030, China
| | - Jian-Guo Zhang
- Department of Neurosurgery, Beijing Tiantan Hospital, Capital Medical University, Tiantan xili 6, Dongcheng, Beijing 100050, China; Beijing Neurosurgical Institute, Tiantan xili 6, Dongcheng, Beijing 100050, China; Beijing Key Laboratory of Neurostimulation, Tiantan xili 6, Dongcheng, Beijing 100050, China
| | - Kai Zhang
- Department of Neurosurgery, Beijing Tiantan Hospital, Capital Medical University, Tiantan xili 6, Dongcheng, Beijing 100050, China; Beijing Neurosurgical Institute, Tiantan xili 6, Dongcheng, Beijing 100050, China; Beijing Key Laboratory of Neurostimulation, Tiantan xili 6, Dongcheng, Beijing 100050, China.
| |
Collapse
|
17
|
Guggenhuber S, Romo-Parra H, Bindila L, Leschik J, Lomazzo E, Remmers F, Zimmermann T, Lerner R, Klugmann M, Pape HC, Lutz B. Impaired 2-AG Signaling in Hippocampal Glutamatergic Neurons: Aggravation of Anxiety-Like Behavior and Unaltered Seizure Susceptibility. Int J Neuropsychopharmacol 2015; 19:pyv091. [PMID: 26232789 PMCID: PMC4772822 DOI: 10.1093/ijnp/pyv091] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/20/2015] [Accepted: 07/29/2015] [Indexed: 12/21/2022] Open
Abstract
BACKGROUND Postsynaptically generated 2-arachidonoylglycerol activates the presynaptic cannabinoid type-1 receptor, which is involved in synaptic plasticity at both glutamatergic and GABAergic synapses. However, the differential function of 2-arachidonoylglycerol signaling at glutamatergic vs GABAergic synapses in the context of animal behavior has not been investigated yet. METHODS Here, we analyzed the role of 2-arachidonoylglycerol signaling selectively in hippocampal glutamatergic neurons. Monoacylglycerol lipase, the primary degrading enzyme of 2-arachidonoylglycerol, is expressed at presynaptic sites of excitatory and inhibitory neurons. By adeno-associated virus-mediated overexpression of monoacylglycerol lipase in glutamatergic neurons of the mouse hippocampus, we selectively interfered with 2-arachidonoylglycerol signaling at glutamatergic synapses of these neurons. RESULTS Genetic modification of monoacylglycerol lipase resulted in a 50% decrease in 2-arachidonoylglycerol tissue levels without affecting the content of the second major endocannabinoid anandamide. A typical electrophysiological read-out for 2-arachidonoylglycerol signaling is the depolarization-induced suppression of excitation and of inhibition. Elevated monoacylglycerol lipase levels at glutamatergic terminals selectively impaired depolarization-induced suppression of excitation, while depolarization-induced suppression of inhibition was not significantly changed. At the behavioral level, mice with impaired hippocampal glutamatergic 2-arachidonoylglycerol signaling exhibited increased anxiety-like behavior but showed no alterations in aversive memory formation and seizure susceptibility. CONCLUSION Our data indicate that 2-arachidonoylglycerol signaling selectively in hippocampal glutamatergic neurons is essential for the animal's adaptation to aversive situations.
Collapse
Affiliation(s)
| | | | | | | | | | | | | | | | | | | | - Beat Lutz
- Institute of Physiological Chemistry, University Medical Center of the Johannes Gutenberg University, Mainz, Germany (Dr Guggenhuber, Dr Bindila, Dr Leschik, Dr Lomazzo, Dr Remmers, Ms Zimmermann, Ms Lerner, Dr Klugmann, and Dr Lutz); Institute of Physiology I (Neurophysiology), Westfaelische Wilhelms-University, Muenster, Germany (Drs Romo-Parra and Pape); Translational Neuroscience Facility, Department of Physiology, School of Medical Sciences, University of New South Wales, UNSW Kensington Campus, Sydney, NSW, Australia (Dr Klugmann).
| |
Collapse
|
18
|
Dholaniya PS, Ghosh S, Surampudi BR, Kondapi AK. A knowledge driven supervised learning approach to identify gene network of differentially up-regulated genes during neuronal senescence in Rattus norvegicus. Biosystems 2015; 135:9-14. [PMID: 26163927 DOI: 10.1016/j.biosystems.2015.07.002] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2015] [Revised: 05/18/2015] [Accepted: 07/06/2015] [Indexed: 12/22/2022]
Abstract
Various approaches have been described to infer the gene interaction network from expression data. Several models based on computational and mathematical methods are available. The fundamental thing in the identification of the gene interaction is their biological relevance. Two genes belonging to the same pathway are more likely to affect the expression of each other than the genes of two different pathways. In the present study, interaction network of genes is described based on upregulated genes during neuronal senescence in the Cerebellar granule neurons of rat. We have adopted a supervised learning method and used it in combination with biological pathway information of the genes to develop a gene interaction network. Further modular analysis of the network has been done to identify senescence-related marker genes. Currently there is no adequate information available about the genes implicated in neuronal senescence. Thus identifying multipath genes belonging to the pathway affected by senescence might be very useful in studying the senescence process.
Collapse
Affiliation(s)
- Pankaj Singh Dholaniya
- Department of Biotechnology and Bioinfomatics, School of Life Sciences, University of Hyderabad, Hyderabad 500046, Telangana, India; Cognitive Science Lab, International Institute of Information Technology (IIIT) Hyderabad, Hyderabad 500032, Telangana, India
| | - Soumitra Ghosh
- School of Computer and Information Sciences, University of Hyderabad, Hyderabad 500046, Telangana, India; Cognitive Science Lab, International Institute of Information Technology (IIIT) Hyderabad, Hyderabad 500032, Telangana, India
| | - Bapi Raju Surampudi
- School of Computer and Information Sciences, University of Hyderabad, Hyderabad 500046, Telangana, India; Cognitive Science Lab, International Institute of Information Technology (IIIT) Hyderabad, Hyderabad 500032, Telangana, India
| | - Anand K Kondapi
- Department of Biotechnology and Bioinfomatics, School of Life Sciences, University of Hyderabad, Hyderabad 500046, Telangana, India; Cognitive Science Lab, International Institute of Information Technology (IIIT) Hyderabad, Hyderabad 500032, Telangana, India.
| |
Collapse
|
19
|
Graham DL, Buendia MA, Chapman MA, Durai HH, Stanwood GD. Deletion of Gαq in the telencephalon alters specific neurobehavioral outcomes. Synapse 2015; 69:434-45. [PMID: 25963901 DOI: 10.1002/syn.21830] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2015] [Revised: 05/01/2015] [Accepted: 05/04/2015] [Indexed: 02/04/2023]
Abstract
G(αq) -coupled receptors are ubiquitously expressed throughout the brain and body, and it has been shown that these receptors and associated signaling cascades are involved in a number of functional outputs, including motor function and learning and memory. Genetic alterations to G(αq) have been implicated in neurodevelopmental disorders such as Sturge-Weber syndrome. Some of these associated disease outcomes have been modeled in laboratory animals, but as G(αq) is expressed in all cell types, it is difficult to differentiate the underlying circuitry or causative neuronal population. To begin to address neuronal cell type diversity in G(αq) function, we utilized a conditional knockout mouse whereby G(αq) was eliminated from telencephalic glutamatergic neurons. Unlike the global G(αq) knockout mouse, we found that these conditional knockout mice were not physically different from control mice, nor did they exhibit any gross motor abnormalities. However, similarly to the constitutive knockout animal, G(αq) conditional knockout mice demonstrated apparent deficits in spatial working memory. Loss of G(αq) from glutamatergic neurons also produced enhanced sensitivity to cocaine-induced locomotion, suggesting that cortical G(αq) signaling may limit behavioral responses to psychostimulants. Screening for a variety of markers of forebrain neuronal architecture revealed no obvious differences in the conditional knockouts, suggesting that the loss of G(αq) in telencephalic excitatory neurons does not result in major alterations in brain structure or neuronal differentiation. Taken together, our results define specific modulation of spatial working memory and psychostimulant responses through disruptions in G(αq) signaling within cerebral cortical glutamatergic neurons.
Collapse
Affiliation(s)
- Devon L Graham
- Department of Biomedical Sciences, Florida State University College of Medicine, Tallahassee, Florida, 32303
| | - Matthew A Buendia
- Department of Pharmacology, Vanderbilt University School of Medicine, Nashville, Tennessee, 37232
| | - Michelle A Chapman
- Department of Pharmacology, Vanderbilt University School of Medicine, Nashville, Tennessee, 37232
| | - Heather H Durai
- Department of Pharmacology, Vanderbilt University School of Medicine, Nashville, Tennessee, 37232
| | - Gregg D Stanwood
- Department of Biomedical Sciences, Florida State University College of Medicine, Tallahassee, Florida, 32303
| |
Collapse
|
20
|
Gupta KP, Dholaniya PS, Chekuri A, Kondapi AK. Analysis of gene expression during aging of CGNs in culture: implication of SLIT2 and NPY in senescence. AGE (DORDRECHT, NETHERLANDS) 2015; 37:62. [PMID: 26047956 PMCID: PMC4493715 DOI: 10.1007/s11357-015-9789-6] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/08/2015] [Accepted: 04/27/2015] [Indexed: 06/04/2023]
Abstract
Senescence is the major key factor that leads to the loss of neurons throughout aging. Cellular senescence is not the consequence of single cause, but there are multiple aspects which may induce senescence in a cell. Various causes such as gene expression, molecular interactions and protein processing and chromatin organization are described as causal factor for senescence. It is well known that the damage to the nuclear or mitochondrial DNA contributes to the aging either directly by inducing the apoptosis/cellular senescence or indirectly by altering cellular functions. The significant nuclear DNA damage with the age is directly associated with the continuous declining in DNA repair. The continuous decline in expression of topoisomerase 2 beta (Topo IIβ) in cultured cerebellar granule neurons over time indicated the decline in the repair of damage DNA. DNA Topo IIβ is an enzyme that is crucial for solving topological problems of DNA and thus has an important role in DNA repair. The enzyme is predominantly present in non-proliferating cells such as neurons. In this paper, we have studied the genes which were differentially expressed over time in cultured cerebellar granule neurons (CGNs) and identified potential genes associated with the senescence. Our results showed that the two genes neuropeptide Y (Npy) and Slit homolog 2 (Drosophila) (Slit2) gradually increase during aging, and upon suppression of these two genes, there was gradual increase in cell viability along with restoration of the expression of Topo IIβ and potential repair proteins.
Collapse
Affiliation(s)
- K. Preeti Gupta
- Department of Biotechnology and Bioinformatics, School of Life Sciences, University of Hyderabad, Hyderabad, 500046 Andhra Pradesh India
| | - Pankaj Singh Dholaniya
- Department of Biotechnology and Bioinformatics, School of Life Sciences, University of Hyderabad, Hyderabad, 500046 Andhra Pradesh India
| | - Anil Chekuri
- Department of Biotechnology and Bioinformatics, School of Life Sciences, University of Hyderabad, Hyderabad, 500046 Andhra Pradesh India
| | - Anand K. Kondapi
- Department of Biotechnology and Bioinformatics, School of Life Sciences, University of Hyderabad, Hyderabad, 500046 Andhra Pradesh India
| |
Collapse
|
21
|
Xie AX, Petravicz J, McCarthy KD. Molecular approaches for manipulating astrocytic signaling in vivo. Front Cell Neurosci 2015; 9:144. [PMID: 25941472 PMCID: PMC4403552 DOI: 10.3389/fncel.2015.00144] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2015] [Accepted: 03/27/2015] [Indexed: 12/26/2022] Open
Abstract
Astrocytes are the predominant glial type in the central nervous system and play important roles in assisting neuronal function and network activity. Astrocytes exhibit complex signaling systems that are essential for their normal function and the homeostasis of the neural network. Altered signaling in astrocytes is closely associated with neurological and psychiatric diseases, suggesting tremendous therapeutic potential of these cells. To further understand astrocyte function in health and disease, it is important to study astrocytic signaling in vivo. In this review, we discuss molecular tools that enable the selective manipulation of astrocytic signaling, including the tools to selectively activate and inactivate astrocyte signaling in vivo. Lastly, we highlight a few tools in development that present strong potential for advancing our understanding of the role of astrocytes in physiology, behavior, and pathology.
Collapse
Affiliation(s)
- Alison X Xie
- Department of Pharmacology, School of Medicine, University of North Carolina at Chapel Hill Chapel Hill, NC, USA
| | - Jeremy Petravicz
- Department of Brain and Cognitive Sciences, Picower Institute for Learning and Memory, Massachusetts Institute of Technology Cambridge, MA, USA
| | - Ken D McCarthy
- Department of Pharmacology, School of Medicine, University of North Carolina at Chapel Hill Chapel Hill, NC, USA
| |
Collapse
|
22
|
Abstract
The antiepileptic potential of Cannabis sativa preparations has been historically recognized. Recent changes in legal restrictions and new well-documented cases reporting remarkably strong beneficial effects have triggered an upsurge in exploiting medical marijuana in patients with refractory epilepsy. Parallel research efforts in the last decade have uncovered the fundamental role of the endogenous cannabinoid system in controlling neuronal network excitability raising hopes for cannabinoid-based therapeutic approaches. However, emerging data show that patient responsiveness varies substantially, and that cannabis administration may sometimes even exacerbate seizures. Qualitative and quantitative chemical variability in cannabis products and personal differences in the etiology of seizures, or in the pathological reorganization of epileptic networks, can all contribute to divergent patient responses. Thus, the consensus view in the neurologist community is that drugs modifying the activity of the endocannabinoid system should first be tested in clinical trials to establish efficacy, safety, dosing, and proper indication in specific forms of epilepsies. To support translation from anecdote-based practice to evidence-based therapy, the present review first introduces current preclinical and clinical efforts for cannabinoid- or endocannabinoid-based epilepsy treatments. Next, recent advances in our knowledge of how endocannabinoid signaling limits abnormal network activity as a central component of the synaptic circuit-breaker system will be reviewed to provide a framework for the underlying neurobiological mechanisms of the beneficial and adverse effects. Finally, accumulating evidence demonstrating robust synapse-specific pathophysiological plasticity of endocannabinoid signaling in epileptic networks will be summarized to gain better understanding of how and when pharmacological interventions may have therapeutic relevance.
Collapse
Affiliation(s)
- István Katona
- Momentum Laboratory of Molecular Neurobiology, Institute of Experimental Medicine, Hungarian Academy of Sciences, Szigony u. 43, Budapest, 1083, Hungary.
| |
Collapse
|
23
|
García del Caño G, Montaña M, Aretxabala X, González-Burguera I, López de Jesús M, Barrondo S, Sallés J. Nuclear phospholipase C-β1 and diacylglycerol LIPASE-α in brain cortical neurons. Adv Biol Regul 2014; 54:12-23. [PMID: 24076015 DOI: 10.1016/j.jbior.2013.09.003] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2013] [Revised: 09/03/2013] [Accepted: 09/03/2013] [Indexed: 06/02/2023]
Abstract
Phosphoinositide (PtdIns) signaling involves the generation of lipid second messengers in response to stimuli in a receptor-mediated manner at the plasma membrane. In neuronal cells of adult brain, the standard model proposes that activation of metabotropic receptors coupled to Phospholipase C-β1 (PLC-β1) is linked to endocannabinoid signaling through the production of diacylglycerol (DAG), which could be systematically metabolized by 1,2-diacylglycerol Lipases (DAGL) to produce an increase of 2-arachidonoyl-glycerol (2-AG), the most abundant endocannabinoid in the brain. However, the existence of a nuclear PtdIns metabolism independent from that occurring elsewhere in the cell is now widely accepted, suggesting that the nucleus constitutes both a functional and a distinct compartment for PtdIns metabolism. In this review, we shall highlight the main achievements in the field of neuronal nuclear inositol lipid metabolism with particular attention to progress made linked to the 2-AG biosynthesis. Our aim has been to identify potential sites of 2-AG synthesis other than the neuronal cytoplasmic compartment by determining the subcellular localization of PLC-β1 and DAGL-α, which is much more abundant than DAGL-β in brain. Our data show that PLC-β1 and DAGL-α are detected in discrete brain regions, with a marked predominance of pyramidal morphologies of positive cortical cells, consistent with their role in the biosynthesis and release of 2-AG by pyramidal neurons to control their synaptic inputs. However, as novelty, we showed here an integrated description of the localization of PLC-β1 and DAGL-α in the neuronal nuclear compartment. We discuss our comparative analysis of the expression patterns of PLC-β1 and DAGL-α, providing some insight into the potential autocrine role of 2-AG production in the neuronal nuclear compartment that probably subserve additional roles to the recognized activation of the CB1 cannabinoid receptor.
Collapse
Affiliation(s)
- Gontzal García del Caño
- Departamento de Neurociencias, Facultad de Farmacia (Vitoria-Gasteiz), Universidad del País Vasco (UPV/EHU), Spain
| | - Mario Montaña
- Departamento de Farmacología, Facultad de Farmacia (Vitoria-Gasteiz), Universidad del País Vasco (UPV/EHU), Spain; CIBERSAM, Spain
| | - Xabier Aretxabala
- Departamento de Neurociencias, Facultad de Farmacia (Vitoria-Gasteiz), Universidad del País Vasco (UPV/EHU), Spain
| | - Imanol González-Burguera
- Departamento de Farmacología, Facultad de Farmacia (Vitoria-Gasteiz), Universidad del País Vasco (UPV/EHU), Spain
| | - Maider López de Jesús
- Departamento de Farmacología, Facultad de Farmacia (Vitoria-Gasteiz), Universidad del País Vasco (UPV/EHU), Spain; CIBERSAM, Spain
| | - Sergio Barrondo
- Departamento de Farmacología, Facultad de Farmacia (Vitoria-Gasteiz), Universidad del País Vasco (UPV/EHU), Spain; CIBERSAM, Spain
| | - Joan Sallés
- Departamento de Farmacología, Facultad de Farmacia (Vitoria-Gasteiz), Universidad del País Vasco (UPV/EHU), Spain; CIBERSAM, Spain.
| |
Collapse
|
24
|
Conrad KL, Davis AR, Silberman Y, Sheffler DJ, Shields AD, Saleh SA, Sen N, Matthies HJG, Javitch JA, Lindsley CW, Winder DG. Yohimbine depresses excitatory transmission in BNST and impairs extinction of cocaine place preference through orexin-dependent, norepinephrine-independent processes. Neuropsychopharmacology 2012; 37:2253-66. [PMID: 22617356 PMCID: PMC3422490 DOI: 10.1038/npp.2012.76] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The alpha2 adrenergic receptor (α(2)-AR) antagonist yohimbine is a widely used tool for the study of anxiogenesis and stress-induced drug-seeking behavior. We previously demonstrated that yohimbine paradoxically depresses excitatory transmission in the bed nucleus of the stria terminalis (BNST), a region critical to the integration of stress and reward pathways, and produces an impairment of extinction of cocaine-conditioned place preference (cocaine-CPP) independent of α(2)-AR signaling. Recent studies show yohimbine-induced drug-seeking behavior is attenuated by orexin receptor 1 (OX(1)R) antagonists. Moreover, yohimbine-induced cocaine-seeking behavior is BNST-dependent. Here, we investigated yohimbine-orexin interactions. Our results demonstrate yohimbine-induced depression of excitatory transmission in the BNST is unaffected by alpha1-AR and corticotropin-releasing factor receptor-1 (CRFR(1)) antagonists, but is (1) blocked by OxR antagonists and (2) absent in brain slices from orexin knockout mice. Although the actions of yohimbine were not mimicked by the norepinephrine transporter blocker reboxetine, they were by exogenously applied orexin A. We find that, as with yohimbine, orexin A depression of excitatory transmission in BNST is OX(1)R-dependent. Finally, we find these ex vivo effects are paralleled in vivo, as yohimbine-induced impairment of cocaine-CPP extinction is blocked by a systemically administered OX(1)R antagonist. These data highlight a new mechanism for orexin on excitatory anxiety circuits and demonstrate that some of the actions of yohimbine may be directly dependent upon orexin signaling and independent of norepinephrine and CRF in the BNST.
Collapse
Affiliation(s)
- Kelly L Conrad
- Department of Molecular Physiology and Biophysics, Vanderbilt University School of Medicine, Nashville, TN, USA
| | - Adeola R Davis
- Department of Center for Molecular Neuroscience, Vanderbilt University School of Medicine, Nashville, TN, USA
| | - Yuval Silberman
- Department of Molecular Physiology and Biophysics, Vanderbilt University School of Medicine, Nashville, TN, USA
| | - Douglas J Sheffler
- Department of Pharmacology, Vanderbilt University School of Medicine, Nashville, TN, USA,Department of Vanderbilt Center for Neuroscience Drug Discovery, Vanderbilt University School of Medicine, Nashville, TN, USA
| | - Angela D Shields
- Department of Molecular Physiology and Biophysics, Vanderbilt University School of Medicine, Nashville, TN, USA
| | - Sam A Saleh
- Department of Pharmacology, Vanderbilt University School of Medicine, Nashville, TN, USA
| | - Namita Sen
- Department of Psychiatry, College of Physicians and Surgeons, Columbia University, New York, NY, USA,Department of Pharmacology, College of Physicians and Surgeons, Columbia University, New York, NY, USA,Department of Pharmacology, Center for Molecular Recognition, College of Physicians and Surgeons, Columbia University, New York, NY, USA
| | - Heinrich JG Matthies
- Department of Center for Molecular Neuroscience, Vanderbilt University School of Medicine, Nashville, TN, USA
| | - Jonathan A Javitch
- Department of Psychiatry, College of Physicians and Surgeons, Columbia University, New York, NY, USA,Department of Pharmacology, College of Physicians and Surgeons, Columbia University, New York, NY, USA,Department of Pharmacology, Center for Molecular Recognition, College of Physicians and Surgeons, Columbia University, New York, NY, USA
| | - Craig W Lindsley
- Department of Pharmacology, Vanderbilt University School of Medicine, Nashville, TN, USA,Department of Vanderbilt Center for Neuroscience Drug Discovery, Vanderbilt University School of Medicine, Nashville, TN, USA
| | - Danny G Winder
- Department of Molecular Physiology and Biophysics, Vanderbilt University School of Medicine, Nashville, TN, USA,Department of Center for Molecular Neuroscience, Vanderbilt University School of Medicine, Nashville, TN, USA,Kennedy Center for Research on Human Development, Vanderbilt University School of Medicine, Nashville, TN, USA,Vanderbilt Brain Institute, Nashville, TN, USA,Department of Molecular Physiology and Biophysics, Vanderbilt University School of Medicine, Nashville, TN 37232, USA, Tel: +1 615 322 1144, Fax: +1 615 322 1462, E-mail:
| |
Collapse
|
25
|
Abstract
Despite being regarded as a hippie science for decades, cannabinoid research has finally found its well-deserved position in mainstream neuroscience. A series of groundbreaking discoveries revealed that endocannabinoid molecules are as widespread and important as conventional neurotransmitters such as glutamate or GABA, yet they act in profoundly unconventional ways. We aim to illustrate how uncovering the molecular, anatomical, and physiological characteristics of endocannabinoid signaling has revealed new mechanistic insights into several fundamental phenomena in synaptic physiology. First, we summarize unexpected advances in the molecular complexity of biogenesis and inactivation of the two endocannabinoids, anandamide and 2-arachidonoylglycerol. Then, we show how these new metabolic routes are integrated into well-known intracellular signaling pathways. These endocannabinoid-producing signalosomes operate in phasic and tonic modes, thereby differentially governing homeostatic, short-term, and long-term synaptic plasticity throughout the brain. Finally, we discuss how cell type- and synapse-specific refinement of endocannabinoid signaling may explain the characteristic behavioral effects of cannabinoids.
Collapse
Affiliation(s)
- István Katona
- Institute of Experimental Medicine, Hungarian Academy of Sciences, 1051 Budapest, Hungary.
| | | |
Collapse
|
26
|
Rudenko V, Rafiuddin A, Leheste JR, Friedman LK. Inverse relationship of cannabimimetic (R+)WIN 55, 212 on behavior and seizure threshold during the juvenile period. Pharmacol Biochem Behav 2011; 100:474-84. [PMID: 22019959 DOI: 10.1016/j.pbb.2011.10.005] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/15/2011] [Revised: 09/26/2011] [Accepted: 10/02/2011] [Indexed: 11/28/2022]
Abstract
Cannabinoids have anti-convulsant effects in both in vivo and in vitro models of status epilepticus. Since the development of spontaneous seizures and neuronal vulnerability are age-dependent, we hypothesized that the anti-convulsant effects of cannabimimetics are also age-dependent. We administered a single injection of varied doses of (R+)WIN 55,212 (0.5, 1, 5 mg/kg) to postnatal (P) day 20 rats 90 min prior to induction of kainate (KA)-induced status epilepticus. The highest dose of (R+)WIN 55,212 (5 mg/kg) resulted in rapid onset of behavioral stupor, loss of balance, stiffening and immobility while standing on hind legs or laying flat in prone position; lower doses had minimal or no behavioral effect. After KA administration, seizure scores and electroencephalography (EEG) recordings were inversely related to (R+)WIN 55,212 dosage whereby higher doses were associated with high seizures scores and synchronous epileptiform activity and low doses with low seizure scores and diminished spiking in the EEG. Immunohistochemistry revealed a dose-dependent reduction in CB1 receptor expression with increasing concentrations of (R+)WIN 55,212 in presence or absence of KA seizures. Nissl and NeuN staining showed hippocampal injury was attenuated only when seizures were mild following low doses of WIN 55,212 (0.5, 1 mg/kg), consistent with the level of CB1 expression. Since low doses abolished seizures without psychotropic side-effects further study may facilitate a groundbreaking cannabamimetic therapeutic strategy to treat early-life seizures. Higher doses had adverse effects on behavior and failed to prevent seizures and protect CA1 neurons possibly due to inactivation or loss of CB1 receptors.
Collapse
Affiliation(s)
- V Rudenko
- New York College of Osteopathic Medicine, Old Westbury, NY 11568, USA
| | | | | | | |
Collapse
|
27
|
Molecular and morphological configuration for 2-arachidonoylglycerol-mediated retrograde signaling at mossy cell-granule cell synapses in the dentate gyrus. J Neurosci 2011; 31:7700-14. [PMID: 21613483 DOI: 10.1523/jneurosci.5665-10.2011] [Citation(s) in RCA: 68] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
2-Arachidonoylglycerol (2-AG) is the endocannabinoid that mediates retrograde suppression of neurotransmission in the brain. In the present study, we investigated the 2-AG signaling system at mossy cell (MC)-granule cell (GC) synapses in the mouse dentate gyrus, an excitatory recurrent circuit where endocannabinoids are thought to suppress epileptogenesis. First, we showed by electrophysiology that 2-AG produced by diacylglycerol lipase α (DGLα) mediated both depolarization-induced suppression of excitation and its enhancement by group I metabotropic glutamate receptor activation at MC-GC synapses, as they were abolished in DGLα-knock-out mice. Immunohistochemistry revealed that DGLα was enriched in the neck portion of GC spines forming synapses with MC terminals, whereas cannabinoid CB(1) receptors accumulated in the terminal portion of MC axons. On the other hand, the major 2-AG-degrading enzyme, monoacylglycerol lipase (MGL), was absent at MC-GC synapses but was expressed in astrocytes and some inhibitory terminals. Serial electron microscopy clarified that a given GC spine was innervated by a single MC terminal and also contacted nonsynaptically by other MC terminals making synapses with other GC spines in the neighborhood. MGL-expressing elements, however, poorly covered GC spines, amounting to 17% of the total surface of GC spines by astrocytes and 4% by inhibitory terminals. Our findings provide a basis for 2-AG-mediated retrograde suppression of MC-GC synaptic transmission and also suggest that 2-AG released from activated GC spines is readily accessible to nearby MC-GC synapses by escaping from enzymatic degradation. This molecular-anatomical configuration will contribute to adjust network activity in the dentate gyrus after enhanced excitation.
Collapse
|
28
|
Kuroda KO, Tachikawa K, Yoshida S, Tsuneoka Y, Numan M. Neuromolecular basis of parental behavior in laboratory mice and rats: with special emphasis on technical issues of using mouse genetics. Prog Neuropsychopharmacol Biol Psychiatry 2011; 35:1205-31. [PMID: 21338647 DOI: 10.1016/j.pnpbp.2011.02.008] [Citation(s) in RCA: 85] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/26/2010] [Revised: 02/14/2011] [Accepted: 02/14/2011] [Indexed: 01/07/2023]
Abstract
To support the well-being of the parent-infant relationship, the neuromolecular mechanisms of parental behaviors should be clarified. From neuroanatomical analyses in laboratory rats, the medial preoptic area (MPOA) has been shown to be of critical importance in parental retrieving behavior. More recently, various gene-targeted mouse strains have been found to be defective in different aspects of parental behaviors, contributing to the identification of molecules and signaling pathways required for the behavior. Therefore, the neuromolecular basis of "mother love" is now a fully approachable research field in modern molecular neuroscience. In this review, we will provide a summary of the required brain areas and gene for parental behavior in laboratory mice (Mus musculus) and rats (Rattus norvegicus). Basic protocols and technical considerations on studying the mechanism of parental behavior using genetically-engineered mouse strains will also be presented.
Collapse
Affiliation(s)
- Kumi O Kuroda
- Unit for Affiliative Social Behavior, RIKEN Brain Science Institute, Saitama 351-0198, Japan.
| | | | | | | | | |
Collapse
|
29
|
Adjobo-Hermans MJW, Goedhart J, van Weeren L, Nijmeijer S, Manders EMM, Offermanns S, Gadella TWJ. Real-time visualization of heterotrimeric G protein Gq activation in living cells. BMC Biol 2011; 9:32. [PMID: 21619590 PMCID: PMC3129320 DOI: 10.1186/1741-7007-9-32] [Citation(s) in RCA: 75] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2011] [Accepted: 05/27/2011] [Indexed: 12/28/2022] Open
Abstract
Background Gq is a heterotrimeric G protein that plays an important role in numerous physiological processes. To delineate the molecular mechanisms and kinetics of signalling through this protein, its activation should be measurable in single living cells. Recently, fluorescence resonance energy transfer (FRET) sensors have been developed for this purpose. Results In this paper, we describe the development of an improved FRET-based Gq activity sensor that consists of a yellow fluorescent protein (YFP)-tagged Gγ2 subunit and a Gαq subunit with an inserted monomeric Turquoise (mTurquoise), the best cyan fluorescent protein variant currently available. This sensor enabled us to determine, for the first time, the kon (2/s) of Gq activation. In addition, we found that the guanine nucleotide exchange factor p63RhoGEF has a profound effect on the number of Gq proteins that become active upon stimulation of endogenous histamine H1 receptors. The sensor was also used to measure ligand-independent activation of the histamine H1 receptor (H1R) upon addition of a hypotonic stimulus. Conclusions Our observations reveal that the application of a truncated mTurquoise as donor and a YFP-tagged Gγ2 as acceptor in FRET-based Gq activity sensors substantially improves their dynamic range. This optimization enables the real-time single cell quantification of Gq signalling dynamics, the influence of accessory proteins and allows future drug screening applications by virtue of its sensitivity.
Collapse
Affiliation(s)
- Merel J W Adjobo-Hermans
- Swammerdam Institute for Life Sciences, Section of Molecular Cytology, van Leeuwenhoek Centre for Advanced Microscopy, University of Amsterdam, Science Park 904, 1098 XH, Amsterdam, The Netherlands
| | | | | | | | | | | | | |
Collapse
|
30
|
Lourenço J, Matias I, Marsicano G, Mulle C. Pharmacological activation of kainate receptors drives endocannabinoid mobilization. J Neurosci 2011; 31:3243-8. [PMID: 21368036 PMCID: PMC6623943 DOI: 10.1523/jneurosci.3512-10.2011] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2010] [Revised: 12/21/2010] [Accepted: 12/30/2010] [Indexed: 02/04/2023] Open
Abstract
Activation of both presynaptic metabotropic cannabinoid type 1 receptors (CB(1)s) and ionotropic kainate receptors (KARs) can efficiently modulate GABA release at many synapses of the CNS. The inhibitory effect of kainic acid (KA) has been ascribed to metabotropic actions, and KAR-induced release of secondary neuromodulatory agents may partly mediate these actions. Here, we investigated the involvement of the endocannabinoid system in the modulation of GABAergic synaptic transmission by pharmacological activation of KARs with KA in CA1 pyramidal neurons of the mouse hippocampus. We show that the depression of GABAergic synaptic transmission induced by KA (3 μm) is strongly inhibited by the simultaneous blockade of CB(1) and GABA(B) receptors with SR141716A (5 μm) and CGP55845 (5 μm), respectively. KA induces a calcium-dependent mobilization of the endocannabinoid anandamide (AEA) by activation of GluK2-containing KARs in postsynaptic pyramidal neurons. Consistently, the effect of KA is prolonged by the inhibitor of AEA degradation URB597 (1 μm) in a CB(1)-dependent manner, but it is not altered by blockade of degradation or synthesis of the other main endocannabinoid 2-arachidonoylglycerol (2AG). Hence, our work reveals that the pharmacological activation of KARs leads to the stimulation of secondary metabotropic signaling systems. In addition, these data further underline the profound mechanistic differences between exogenous and endogenous activation of KARs in the hippocampus.
Collapse
MESH Headings
- Animals
- Cannabinoid Receptor Modulators/metabolism
- Cannabinoid Receptor Modulators/physiology
- Endocannabinoids
- Hippocampus/drug effects
- Hippocampus/metabolism
- Kainic Acid/pharmacology
- Mice
- Mice, Inbred C57BL
- Mice, Knockout
- Piperidines/pharmacology
- Pyrazoles/pharmacology
- Receptor Cross-Talk/drug effects
- Receptor Cross-Talk/physiology
- Receptor, Cannabinoid, CB1/antagonists & inhibitors
- Receptor, Cannabinoid, CB1/metabolism
- Receptors, GABA-B/metabolism
- Receptors, Kainic Acid/agonists
- Receptors, Kainic Acid/metabolism
- Receptors, Kainic Acid/physiology
- Rimonabant
- Signal Transduction/drug effects
- Signal Transduction/physiology
- GluK2 Kainate Receptor
Collapse
Affiliation(s)
- Joana Lourenço
- INSERM U862 NeuroCentre Magendie, “Endocannabinoids and Neuroadaptation,” 33077 Bordeaux, France
- PhD Programme in Experimental Biology and Biomedicine, Center for Neuroscience and Cell Biology, University of Coimbra, 3004-504 Coimbra, Portugal
- Laboratoire “Physiologie Cellulaire de la Synapse” CNRS UMR 5091, 33077 Bordeaux, France, and
- University of Bordeaux, 33077 Bordeaux, France
| | - Isabel Matias
- INSERM U862 NeuroCentre Magendie, “Endocannabinoids and Neuroadaptation,” 33077 Bordeaux, France
- University of Bordeaux, 33077 Bordeaux, France
| | - Giovanni Marsicano
- INSERM U862 NeuroCentre Magendie, “Endocannabinoids and Neuroadaptation,” 33077 Bordeaux, France
- University of Bordeaux, 33077 Bordeaux, France
| | - Christophe Mulle
- Laboratoire “Physiologie Cellulaire de la Synapse” CNRS UMR 5091, 33077 Bordeaux, France, and
- University of Bordeaux, 33077 Bordeaux, France
| |
Collapse
|
31
|
Di Marzo V. Endocannabinoid signaling in the brain: biosynthetic mechanisms in the limelight. Nat Neurosci 2011; 14:9-15. [PMID: 21187849 DOI: 10.1038/nn.2720] [Citation(s) in RCA: 134] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Studies of the endocannabinoid system in the CNS have been mostly focused on endocannabinoid receptors and inactivating mechanisms. Until recently, very little was known about the role of biosynthetic enzymes in endocannabinoid signaling. New data from the recent development of pharmacological and genetic tools for the study of these enzymes point to their fundamental role in determining where and when endocannabinoids function, and raise the possibility of new intriguing and previously unsuspected concepts in the general strategy of endocannabinoid signaling. However, even with these new tools, the cross-talk between anandamide and 2-arachidonoylglycerol biosynthesis makes it difficult to dissect one from the other, and data will need to be interpreted with this in mind.
Collapse
Affiliation(s)
- Vincenzo Di Marzo
- Endocannabinoid Research Group, Institute of Biomolecular Chemistry, CNR, Pozzuoli, Italy.
| |
Collapse
|
32
|
Clementina M. VR, Martin F.J. P, Vinogradova L, Gilles van L. Endocannabinoid system protects against cryptogenic seizures. Pharmacol Rep 2011; 63:165-8. [DOI: 10.1016/s1734-1140(11)70411-x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2010] [Revised: 08/06/2010] [Indexed: 12/12/2022]
|
33
|
Guggenhuber S, Monory K, Lutz B, Klugmann M. AAV vector-mediated overexpression of CB1 cannabinoid receptor in pyramidal neurons of the hippocampus protects against seizure-induced excitoxicity. PLoS One 2010; 5:e15707. [PMID: 21203567 PMCID: PMC3006205 DOI: 10.1371/journal.pone.0015707] [Citation(s) in RCA: 66] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2010] [Accepted: 11/19/2010] [Indexed: 11/19/2022] Open
Abstract
The CB1 cannabinoid receptor is the most abundant G-protein coupled receptor in the brain and a key regulator of neuronal excitability. There is strong evidence that CB1 receptor on glutamatergic hippocampal neurons is beneficial to alleviate epileptiform seizures in mouse and man. Therefore, we hypothesized that experimentally increased CB1 gene dosage in principal neurons would have therapeutic effects in kainic acid (KA)-induced hippocampal pathogenesis. Here, we show that virus-mediated conditional overexpression of CB1 receptor in pyramidal and mossy cells of the hippocampus is neuroprotective and moderates convulsions in the acute KA seizure model in mice. We introduce a recombinant adeno-associated virus (AAV) genome with a short stop element flanked by loxP sites, for highly efficient attenuation of transgene expression on the transcriptional level. The presence of Cre-recombinase is strictly necessary for expression of reporter proteins or CB1 receptor in vitro and in vivo. Transgenic CB1 receptor immunoreactivity is targeted to glutamatergic neurons after stereotaxic delivery of AAV to the dorsal hippocampus of the driver mice NEX-cre. Increased CB1 receptor protein levels in hippocampal lysates of AAV-treated Cre-mice is paralleled by enhanced cannabinoid-induced G-protein activation. KA-induced seizure severity and mortality is reduced in CB1 receptor overexpressors compared with AAV-treated control animals. Neuronal damage in the hippocampal CA3 field is specifically absent from AAV-treated Cre-transgenics, but evident throughout cortical areas of both treatment groups. Our data provide further evidence for a role of increased CB1 signaling in pyramidal hippocampal neurons as a safeguard against the adverse effects of excessive excitatory network activity.
Collapse
Affiliation(s)
- Stephan Guggenhuber
- Institute of Physiological Chemistry, University Medical Center of the Johannes Gutenberg University, Mainz, Germany
| | - Krisztina Monory
- Institute of Physiological Chemistry, University Medical Center of the Johannes Gutenberg University, Mainz, Germany
| | - Beat Lutz
- Institute of Physiological Chemistry, University Medical Center of the Johannes Gutenberg University, Mainz, Germany
- * E-mail: (MK); (BL)
| | - Matthias Klugmann
- Institute of Physiological Chemistry, University Medical Center of the Johannes Gutenberg University, Mainz, Germany
- * E-mail: (MK); (BL)
| |
Collapse
|
34
|
Grueter BA, Brasnjo G, Malenka RC. Postsynaptic TRPV1 triggers cell type-specific long-term depression in the nucleus accumbens. Nat Neurosci 2010; 13:1519-25. [PMID: 21076424 DOI: 10.1038/nn.2685] [Citation(s) in RCA: 262] [Impact Index Per Article: 18.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2010] [Accepted: 09/22/2010] [Indexed: 12/12/2022]
Abstract
Synaptic modifications in the nucleus accumbens (NAc) are important for adaptive and pathological reward-dependent learning. Medium spiny neurons (MSNs), the major cell type in the NAc, participate in two parallel circuits that subserve distinct behavioral functions, yet little is known about differences in their electrophysiological and synaptic properties. Using bacterial artificial chromosome transgenic mice, we found that synaptic activation of group I metabotropic glutamate receptors in NAc MSNs in the indirect, but not direct, pathway led to the production of endocannabinoids, which activated presynaptic CB1 receptors to trigger endocannabinoid-mediated long-term depression (eCB-LTD) as well as postsynaptic transient receptor potential vanilloid 1 (TRPV1) channels to trigger a form of LTD resulting from endocytosis of AMPA receptors. These results reveal a previously unknown action of TRPV1 channels and indicate that the postsynaptic generation of endocannabinoids can modulate synaptic strength in a cell type-specific fashion by activating distinct pre- and postsynaptic targets.
Collapse
Affiliation(s)
- Brad A Grueter
- Nancy Pritzker Laboratory, Department of Psychiatry and Behavioral Sciences, Stanford University School of Medicine, Palo Alto, California, USA
| | | | | |
Collapse
|
35
|
Coulon P, Kanyshkova T, Broicher T, Munsch T, Wettschureck N, Seidenbecher T, Meuth SG, Offermanns S, Pape HC, Budde T. Activity Modes in Thalamocortical Relay Neurons are Modulated by G(q)/G(11) Family G-proteins - Serotonergic and Glutamatergic Signaling. Front Cell Neurosci 2010; 4:132. [PMID: 21267426 PMCID: PMC3024565 DOI: 10.3389/fncel.2010.00132] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2009] [Accepted: 09/28/2010] [Indexed: 11/13/2022] Open
Abstract
In thalamocortical relay (TC) neurons, G-protein-coupled receptors play an important part in the control of activity modes. A conditional Gα(q) knockout on the background of a constitutive Gα(11) knockout (Gα(q)/Gα(11) (-/-)) was used to determine the contribution of Gq/G11 family G-proteins to metabotropic serotonin (5-HT) and glutamate (Glu) function in the dorsal part of the lateral geniculate nucleus (dLGN). In control mice, current clamp recordings showed that α-m-5-HT induced a depolarization of V(rest) which was sufficient to suppress burst firing. This depolarization was concentration-dependent (100 μM: +6 ± 1 mV, n = 10; 200 μM: +10 ± 1 mV, n = 7) and had a conditioning effect on the activation of other Gα(q)-mediated pathways. The depolarization was significantly reduced in Gα(q)/Gα(11) (-/-) (100 μM: 3 ± 1 mV, n = 11; 200 μM: 5 ± 1 mV, n = 6) and was apparently insufficient to suppress burst firing. Activating Gα(q)-coupled muscarinic receptors affected the magnitude of α-m-5-HT-induced effects in a reciprocal manner. Furthermore, the depolarizing effect of mGluR1 agonists was significantly reduced in Gα(q)/Gα(11) (-/-) mice. Immunohistochemical stainings revealed binding of 5-HT(2C)R- and mGluR1α-, but not of 5-HT(2A)R-specific antibodies in the dLGN of Gα(q)/Gα(11) (-/-) mice. In conclusion, these findings demonstrate that transmitters of ascending brainstem fibers and corticofugal fibers both signal via a central element in the form of Gq/G11-mediated pathways to control activity modes in the TC system.
Collapse
Affiliation(s)
- Philippe Coulon
- Institut für Physiologie I, Westfälische Wilhelms-Universität Münster Münster, Germany
| | | | | | | | | | | | | | | | | | | |
Collapse
|
36
|
Min R, Di Marzo V, Mansvelder HD. DAG lipase involvement in depolarization-induced suppression of inhibition: does endocannabinoid biosynthesis always meet the demand? Neuroscientist 2010; 16:608-13. [PMID: 20837870 DOI: 10.1177/1073858410373281] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Hippocampal depolarization-induced suppression of inhibition (DSI) is a robust form of short-term synaptic plasticity. DSI is mediated by endocannabinoid signaling. Since this discovery, pinning down the endogenous cannabinoid receptor ligand that mediates DSI has been problematic. Blocking degradation of the endocannabinoid 2-arachidonoyl glycerol (2-AG) lengthens DSI, which seems to indicate that 2-AG mediates DSI. In contrast, pharmacological inhibition of the 2-AG-synthesizing enzyme diacylglycerol lipase (DAGL) has yielded conflicting results: DAGL inhibitors often fail to block hippocampal DSI. Recently, 2 studies seem to have cornered this problem using DAGL knockout mice. Hippocampal DSI is absent in DAGL-α knockout mice, pointing to a key role for 2-AG in DSI. However, these studies do not reconcile the discrepancy with pharmacological experiments. Here, we argue that the seeming contradiction between results from pharmacological and genetic approaches may be explained in several ways. We suggest that the contradiction may be resolved by taking a different perspective on endocannabinoid signaling: in some forms of endocannabinoid-mediated signaling endocannabinoids might not be necessarily produced "on demand" but presynthesized and stored until needed.
Collapse
Affiliation(s)
- Rogier Min
- Department of Physiology, University of Bern, Bern, Switzerland.
| | | | | |
Collapse
|
37
|
Involvement of histamine 1 receptor in seizure susceptibility and neuroprotection in immature mice. Epilepsy Res 2010; 90:8-15. [DOI: 10.1016/j.eplepsyres.2010.02.012] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2009] [Revised: 02/24/2010] [Accepted: 02/27/2010] [Indexed: 01/09/2023]
|
38
|
Thathiah A, De Strooper B. G protein-coupled receptors, cholinergic dysfunction, and Abeta toxicity in Alzheimer's disease. Sci Signal 2009; 2:re8. [PMID: 19843960 DOI: 10.1126/scisignal.293re8] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
The beta-amyloid (Abeta) peptide is associated with the pathogenesis of Alzheimer's disease (AD). Evidence gathered over the last two decades suggests that the gradual accumulation of soluble and insoluble Abeta peptide species triggers a cascade of events that leads to the clinical manifestation of AD. Abeta accumulation has also been associated with the cholinergic dysfunction observed in AD, which is characterized by diminished acetylcholine release and impaired coupling of the muscarinic acetylcholine receptors (mAChRs) to heterotrimeric GTP-binding proteins (G proteins). Although the mechanism of Abeta-mediated toxicity is not clearly understood, evidence shows that Abeta accumulation has an effect on the oligomerization of the angiotensin II (AngII) AT(2) (angiotensin type 2) receptor and sequestration of the Galpha(q/11) family of G proteins. Sequestration of Galpha(q/11) results in dysfunctional coupling and signaling between M(1) mAChR and Galpha(q/11) and accompanies neurodegeneration, tau phosphorylation, and neuronal loss in an AD transgenic mouse model. Collectively, these results provide a putative link among Abeta toxicity, AT(2) receptor oligomerization, and disruption of the signaling pathway through M(1) mAChR and Galpha(q/11) and potentially contribute to our understanding of the cholinergic deficit observed in AD.
Collapse
|
39
|
Iuvone T, Esposito G, De Filippis D, Scuderi C, Steardo L. Cannabidiol: a promising drug for neurodegenerative disorders? CNS Neurosci Ther 2009; 15:65-75. [PMID: 19228180 DOI: 10.1111/j.1755-5949.2008.00065.x] [Citation(s) in RCA: 148] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
Neurodegenerative diseases represent, nowadays, one of the main causes of death in the industrialized country. They are characterized by a loss of neurons in particular regions of the nervous system. It is believed that this nerve cell loss underlies the subsequent decline in cognitive and motor function that patients experience in these diseases. A range of mutant genes and environmental toxins have been implicated in the cause of neurodegenerative disorders but the mechanism remains largely unknown. At present, inflammation, a common denominator among the diverse list of neurodegenerative diseases, has been implicated as a critical mechanism that is responsible for the progressive nature of neurodegeneration. Since, at present, there are few therapies for the wide range of neurodegenerative diseases, scientists are still in search of new therapeutic approaches to the problem. An early contribution of neuroprotective and antiinflammatory strategies for these disorders seems particularly desirable because isolated treatments cannot be effective. In this contest, marijuana derivatives have attracted special interest, although these compounds have always raised several practical and ethical problems for their potential abuse. Nevertheless, among Cannabis compounds, cannabidiol (CBD), which lacks any unwanted psychotropic effect, may represent a very promising agent with the highest prospect for therapeutic use.
Collapse
Affiliation(s)
- Teresa Iuvone
- Department of Experimental Pharmacology, Faculty of Pharmacy, University of Naples Federico II, Via D. Montesano 49, Naples, Italy.
| | | | | | | | | |
Collapse
|
40
|
AbdAlla S, Lother H, el Missiry A, Sergeev P, Langer A, el Faramawy Y, Quitterer U. Dominant Negative AT2 Receptor Oligomers Induce G-protein Arrest and Symptoms of Neurodegeneration. J Biol Chem 2009; 284:6566-74. [DOI: 10.1074/jbc.m808277200] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
|
41
|
Malcher-Lopes R, Buzzi M. Glucocorticoid-regulated crosstalk between arachidonic acid and endocannabinoid biochemical pathways coordinates cognitive-, neuroimmune-, and energy homeostasis-related adaptations to stress. VITAMINS AND HORMONES 2009; 81:263-313. [PMID: 19647116 DOI: 10.1016/s0083-6729(09)81011-x] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Arachidonic acid and its derivatives constitute the major group of signaling molecules involved in the innate immune response and its communication with all cellular and systemic aspects involved on homeostasis maintenance. Glucocorticoids spread throughout the organism their influences over key enzymatic steps of the arachidonic acid biochemical pathways, leading, in the central nervous system, to a shift favoring the synthesis of anti-inflammatory endocannabinoids over proinflammatory metabolites, such as prostaglandins. This shift modifies local immune-inflammatory response and neuronal activity to ultimately coordinate cognitive, behavioral, neuroendocrine, neuroimmune, physiological, and metabolic adjustments to basal and stress conditions. In the hypothalamus, a reciprocal feedback between glucocorticoids and arachidonate-containing molecules provides a mechanism for homeostatic control. This neurochemical switch is susceptible to fine-tuning by neuropeptides, cytokines, and hormones, such as leptin and interleukin-1beta, assuring functional integration between energy homeostasis control and the immune/stress response.
Collapse
Affiliation(s)
- Renato Malcher-Lopes
- Laboratory of Mass Spectrometry, EMBRAPA-Center for Genetic Resources and Biotechnology, Brasília-DF, Brazil
| | | |
Collapse
|
42
|
AbdAlla S, Lother H, el Missiry A, Langer A, Sergeev P, el Faramawy Y, Quitterer U. Angiotensin II AT2 receptor oligomers mediate G-protein dysfunction in an animal model of Alzheimer disease. J Biol Chem 2008; 284:6554-65. [PMID: 19074441 DOI: 10.1074/jbc.m807746200] [Citation(s) in RCA: 65] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Progressive neurodegeneration and decline of cognitive functions are major hallmarks of Alzheimer disease (AD). Neurodegeneration in AD correlates with dysfunction of diverse signal transduction mechanisms, such as the G-protein-stimulated phosphoinositide hydrolysis mediated by Galphaq/11. We report here that impaired Galphaq/11-stimulated signaling in brains of AD patients and mice correlated with the appearance of cross-linked oligomeric angiotensin II AT2 receptors sequestering Galphaq/11. Amyloid beta (Abeta) was causal to AT2 oligomerization, because cerebral microinjection of Abeta triggered AT2 oligomerization in the hippocampus of mice in a dose-dependent manner. Abeta induced AT2 oligomerization by a two-step process of oxidative and transglutaminase-dependent cross-linking. The induction of AT2 oligomers in a transgenic mouse model with AD-like symptoms was associated with Galphaq/11 dysfunction and enhanced neurodegeneration. Vice versa, stereotactic inhibition of AT2 oligomers by RNA interference prevented the impairment of Galphaq/11 and delayed Tau phosphorylation. Thus, Abeta induces the formation of cross-linked AT2 oligomers that contribute to the dysfunction of Galphaq/11 in an animal model of Alzheimer disease.
Collapse
Affiliation(s)
- Said AbdAlla
- Heinrich-Pette-Institute, Martinistrasse 52, D-20251 Hamburg, Germany
| | | | | | | | | | | | | |
Collapse
|
43
|
Vellani V, Petrosino S, De Petrocellis L, Valenti M, Prandini M, Magherini PC, McNaughton PA, Di Marzo V. Functional lipidomics. Calcium-independent activation of endocannabinoid/endovanilloid lipid signalling in sensory neurons by protein kinases C and A and thrombin. Neuropharmacology 2008; 55:1274-9. [DOI: 10.1016/j.neuropharm.2008.01.010] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2007] [Revised: 01/24/2008] [Accepted: 01/26/2008] [Indexed: 01/21/2023]
|
44
|
Abstract
The human costs of stroke are very large and growing; it is the third largest cause of death in the United States and survivors are often faced with loss of ability to function independently. There is a large need for therapeutic approaches that act to protect neurons from the injury produced by ischemia and reperfusion. The goal of this review is to introduce and discuss the available data that endogenous cannabinoid signaling is altered during ischemia and that it contributes to the consequences of ischemia-induced injury. Overall, the available data suggest that inhibition of CB1 receptor activation together with increased CB2 receptor activation produces beneficial effects.
Collapse
Affiliation(s)
- Cecilia J Hillard
- Department of Pharmacology and Toxicology, Medical College of Wisconsin; Milwaukee, WI 53226, USA.
| |
Collapse
|
45
|
Abstract
Cannabis sativa is one of the oldest herbal plants in the history of medicine. It was used in various therapeutic applications from pain to epilepsy, but its psychotropic effect has reduced its usage in recent medical practice. However, renewed interest has been fueled by major discoveries revealing that cannabis-derived compounds act through a signaling pathway in the human body. Here we review recent advances showing that endocannabinoid signaling is a key regulator of synaptic communication throughout the central nervous system. Its underlying molecular architecture is highly conserved in synapses from the spinal cord to the neocortex, and as a negative feed-back signal, it provides protection against excess presynaptic activity. The endocannabinoid signaling machinery operates on demand in a synapse-specific manner; therefore, its modulation offers new therapeutic opportunities for the selective control of deleterious neuronal activity in several neurological disorders.
Collapse
|
46
|
Placzek EA, Okamoto Y, Ueda N, Barker EL. Membrane microdomains and metabolic pathways that define anandamide and 2-arachidonyl glycerol biosynthesis and breakdown. Neuropharmacology 2008; 55:1095-104. [PMID: 18760289 DOI: 10.1016/j.neuropharm.2008.07.047] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2008] [Revised: 07/16/2008] [Accepted: 07/22/2008] [Indexed: 01/31/2023]
Abstract
Anandamide (AEA) and 2-arachidonyl glycerol (2-AG), endogenous ligands for the CB1 and CB2 cannabinoid receptors, are referred to as endocannabinoids because they mimic the actions of delta9-tetrahydrocannabinol (Delta9-THC), a plant-derived cannabinoid. The processes by which AEA and 2-AG are biosynthesized, released, taken up by cells and hydrolyzed have been of much interest as potential therapeutic targets. In this review we will discuss the progress that has been made to characterize the primary pathways for AEA and 2-AG formation and breakdown as well as the role that specialized membrane microdomains known as lipid rafts play in these processes. Furthermore we will review the recent advances made to track and detect AEA in biological matrices.
Collapse
Affiliation(s)
- Ekaterina A Placzek
- Department of Medicinal Chemistry and Molecular Pharmacology, Purdue University, 575 Stadium Mall Drive, Room 202C, West Lafayette, IN 47904, USA
| | | | | | | |
Collapse
|
47
|
Di Marzo V. Targeting the endocannabinoid system: to enhance or reduce? Nat Rev Drug Discov 2008; 7:438-55. [PMID: 18446159 DOI: 10.1038/nrd2553] [Citation(s) in RCA: 612] [Impact Index Per Article: 38.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
As our understanding of the endocannabinoids improves, so does the awareness of their complexity. During pathological states, the levels of these mediators in tissues change, and their effects vary from those of protective endogenous compounds to those of dysregulated signals. These observations led to the discovery of compounds that either prolong the lifespan of endocannabinoids or tone down their action for the potential future treatment of pain, affective and neurodegenerative disorders, gastrointestinal inflammation, obesity and metabolic dysfunctions, cardiovascular conditions and liver diseases. When moving to the clinic, however, the pleiotropic nature of endocannabinoid functions will require careful judgement in the choice of patients and stage of the disorder for treatment.
Collapse
Affiliation(s)
- Vincenzo Di Marzo
- Endocannabinoid Research Group, Institute of Biomolecular Chemistry, National Research Council (CNR), Via Campi Flegrei 34, 80078, Pozzuoli, Naples, Italy.
| |
Collapse
|
48
|
Abstract
The finding of specific binding sites for Delta(9)-tetrahydrocannabinol, the psychoactive component of Cannabis sativa, has led to the discovery of the endocannabinoid system and has emphasised the physiological and pathological relevance of endocannabidoid lipid signalling. Subsequently, an increasing number of papers have been published on the biochemistry and pharmacology of endocannabinoids. An overview of the current understanding of structure and metabolism of the best studied endocannabinoids is provided, with a focus on the mechanisms responsible for their biosynthesis and inactivation.
Collapse
Affiliation(s)
- T Bisogno
- Endocannabinoid Research Group, Istituto di Chimica Biomolecolare, Consiglio Nazionale delle Ricerche, Pozzuoli, Naples, Italy.
| |
Collapse
|
49
|
Downregulation of the CB1 cannabinoid receptor and related molecular elements of the endocannabinoid system in epileptic human hippocampus. J Neurosci 2008; 28:2976-90. [PMID: 18354002 DOI: 10.1523/jneurosci.4465-07.2008] [Citation(s) in RCA: 174] [Impact Index Per Article: 10.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Endocannabinoid signaling is a key regulator of synaptic neurotransmission throughout the brain. Compelling evidence shows that its perturbation leads to development of epileptic seizures, thus indicating that endocannabinoids play an intrinsic protective role in suppressing pathologic neuronal excitability. To elucidate whether long-term reorganization of endocannabinoid signaling occurs in epileptic patients, we performed comparative expression profiling along with quantitative electron microscopic analysis in control (postmortem samples from subjects with no signs of neurological disorders) and epileptic (surgically removed from patients with intractable temporal lobe epilepsy) hippocampal tissue. Quantitative PCR measurements revealed that CB(1) cannabinoid receptor mRNA was downregulated to one-third of its control value in epileptic hippocampus. Likewise, the cannabinoid receptor-interacting protein-1a mRNA was decreased, whereas 1b isoform levels were unaltered. Expression of diacylglycerol lipase-alpha, an enzyme responsible for 2-arachidonoylglycerol synthesis, was also reduced by approximately 60%, whereas its related beta isoform levels were unchanged. Expression level of N-acyl-phosphatidylethanolamine-hydrolyzing phospholipase D and fatty acid amide hydrolase, metabolic enzymes of anandamide, and 2-arachidonoylglycerol's degrading enzyme monoacylglycerol lipase did not change. The density of CB(1) immunolabeling was also decreased in epileptic hippocampus, predominantly in the dentate gyrus, where quantitative electron microscopic analysis did not reveal changes in the ratio of CB(1)-positive GABAergic boutons, but uncovered robust reduction in the fraction of CB(1)-positive glutamatergic axon terminals. These findings show that a neuroprotective machinery involving endocannabinoids is impaired in epileptic human hippocampus and imply that downregulation of CB(1) receptors and related molecular components of the endocannabinoid system may facilitate the deleterious effects of increased network excitability.
Collapse
|
50
|
Muscarinic ACh receptor-mediated control of thalamic activity via G(q)/G (11)-family G-proteins. Pflugers Arch 2008; 456:1049-60. [PMID: 18350314 DOI: 10.1007/s00424-008-0473-x] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2007] [Revised: 01/16/2008] [Accepted: 02/07/2008] [Indexed: 12/25/2022]
Abstract
A genetic knock out was used to determine the specific contribution of G(q)/G(11)-family G-proteins to the function of thalamocortical relay (TC) neurons. Disruption of Galpha(q) function in a conditional forebrain-specific Galpha(q)/Galpha(11)-double-deficient mouse line (Galpha(q)/Galpha(11)(-/-) had no effects on the resting membrane potential (V (rest)) and the amplitude of the standing outward current (I (SO)). Stimulation of muscarinic acetylcholine (ACh) receptors (mAChR; muscarine, 50 microM) induced a decrease in I (SO) amplitude in wild-type mice (36 +/- 4%, n = 5), a constitutive Galpha(11)-deficient mouse line (Galpha(11)(-/-; 36 +/- 3%, n = 8), and Galpha(q)/Galpha(11)(-/-) (11 +/- 2%, n = 16). Current-clamp recordings revealed a muscarine-induced positive shift in V (rest) of 23 +/- 2 mV (n = 6), 18 +/- 5 mV (n = 5), and 2 +/- 1 mV (n = 9) in wild type, Galpha(11)(-/-), and Galpha(q)/Galpha(11)(-/-), respectively. This depolarization was associated with a change in TC neuron activity from burst to tonic firing in wild type and Galpha(11)(-/-), but not in Galpha(q)/Galpha(11)(-/-). The use of specific antibodies and of pharmacological agents with preferred affinity points to the contribution of m(1)AChR and m(3)AChR. In conclusion, we present two novel aspects of the physiology of the thalamocortical system by demonstrating that the depolarization of TC neurons, which is induced by the action of transmitters of ascending brainstem fibers, is governed roughly equally by both m(1)AChR and m(3)AChR and is transduced by Galpha(q) but not by Galpha(11).
Collapse
|