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Smith G, McCoy K, Di Prisco GV, Kuklish A, Grant E, Bhat M, Patel S, Mackie K, Atwood B, Kalinovsky A. Deletion of endocannabinoid synthesizing enzyme DAGLα from cerebellar Purkinje cells decreases social preference and elevates anxiety. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.08.08.607068. [PMID: 39211155 PMCID: PMC11361171 DOI: 10.1101/2024.08.08.607068] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/04/2024]
Abstract
The endocannabinoid (eCB) signaling system is robustly expressed in the cerebellum starting from the embryonic developmental stages to adulthood. There it plays a key role in regulating cerebellar synaptic plasticity and excitability, suggesting that impaired eCB signaling will lead to deficits in cerebellar adjustments of ongoing behaviors and cerebellar learning. Indeed, human mutations in DAGLα are associated with neurodevelopmental disorders. In this study, we show that selective deletion of the eCB synthesizing enzyme diacylglycerol lipase alpha (Daglα) from mouse cerebellar Purkinje cells (PCs) alters motor and social behaviors, disrupts short-term synaptic plasticity in both excitatory and inhibitory synapses, and reduces Purkinje cell activity during social exploration. Our results provide the first evidence for cerebellar-specific eCB regulation of social behaviors and implicate eCB regulation of synaptic plasticity and PC activity as the neural substrates contributing to these deficits. Abstract Figure
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Feng T, Zhang L, Wu Y, Tang L, Chen X, Li Y, Shan C. Exploring the Therapeutic Effects and Mechanisms of Transcranial Alternating Current Stimulation on Improving Walking Ability in Stroke Patients via Modulating Cerebellar Gamma Frequency Band-a Narrative Review. CEREBELLUM (LONDON, ENGLAND) 2024; 23:1593-1603. [PMID: 37962773 PMCID: PMC11269344 DOI: 10.1007/s12311-023-01632-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 11/01/2023] [Indexed: 11/15/2023]
Abstract
The cerebellum plays an important role in maintaining balance, posture control, muscle tone, and lower limb coordination in healthy individuals and stroke patients. At the same time, the relationship between cerebellum and motor learning has been widely concerned in recent years. Due to the relatively intact structure preservation and high plasticity after supratentorial stroke, non-invasive neuromodulation targeting the cerebellum is increasingly used to treat abnormal gait in stroke patients. The gamma frequency of transcranial alternating current stimulation (tACS) is commonly used to improve motor learning. It is an essential endogenous EEG oscillation in the gamma range during the swing phase, and rhythmic movement changes in the gait cycle. However, the effect of cerebellar tACS in the gamma frequency band on balance and walking after stroke remains unknown and requires further investigation.
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Affiliation(s)
- Tingyi Feng
- Department of Rehabilitation Medicine, Yueyang Hospital of Integrated Traditional Chinese and Western Medicine, Shanghai University of Traditional Chinese Medicine, Shanghai, China
| | - Lichao Zhang
- Department of Rehabilitation Medicine, Yueyang Hospital of Integrated Traditional Chinese and Western Medicine, Shanghai University of Traditional Chinese Medicine, Shanghai, China
| | - Yuwei Wu
- Department of Rehabilitation Medicine, Yueyang Hospital of Integrated Traditional Chinese and Western Medicine, Shanghai University of Traditional Chinese Medicine, Shanghai, China
| | - Lin Tang
- Department of Rehabilitation Medicine, Yueyang Hospital of Integrated Traditional Chinese and Western Medicine, Shanghai University of Traditional Chinese Medicine, Shanghai, China
| | - Xixi Chen
- Department of Rehabilitation Medicine, Yueyang Hospital of Integrated Traditional Chinese and Western Medicine, Shanghai University of Traditional Chinese Medicine, Shanghai, China
- School of Rehabilitation Science, Shanghai University of Traditional Chinese Medicine, Shanghai, China
| | - Yuanli Li
- Engineering Research Center of Traditional Chinese Medicine Intelligent Rehabilitation, Ministry of Education, Shanghai, China
- Department of Rehabilitation, Shanghai Seventh People's Hospital, Shanghai University of Traditional Chinese Medicine, Shanghai, China
| | - Chunlei Shan
- Department of Rehabilitation Medicine, Yueyang Hospital of Integrated Traditional Chinese and Western Medicine, Shanghai University of Traditional Chinese Medicine, Shanghai, China.
- Institute of Rehabilitation, Shanghai Jiao Tong University School of Medicine, Shanghai, China.
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3
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Stachowicz K. Interactions between metabotropic glutamate and CB1 receptors: implications for mood, cognition, and synaptic signaling based on data from mGluR and CB1R-targeting drugs. Pharmacol Rep 2024:10.1007/s43440-024-00612-6. [PMID: 38941064 DOI: 10.1007/s43440-024-00612-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2024] [Revised: 06/07/2024] [Accepted: 06/07/2024] [Indexed: 06/29/2024]
Abstract
Metabotropic glutamate receptors (mGluRs) are part of the G protein-coupled receptors (GPCRs) family. They are coupled to Gαq (group I) or Gi/o (groups II and III) proteins, which result in the generation of diacylglycerol (DAG) and inositol 1,4,5-triphosphate (IP3) or the inhibition of adenylyl cyclase, respectively. mGluRs have been implicated in anxiety, depression, learning, and synaptic plasticity. Similarly, CB1 cannabinoid receptors (CB1Rs), also GPCRs, play roles in cognitive function and mood regulation through Gαi/o-mediated inhibition of adenylyl cyclase. Both mGluRs and CB1Rs exhibit surface labeling and undergo endocytosis. Given the similar cellular distribution and mechanisms of action, this review complies with fundamental data on the potential interactions and mutual regulation of mGluRs and CB1Rs in the context of depression, anxiety, and cognition, providing pioneering insights into their interplay.
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Affiliation(s)
- Katarzyna Stachowicz
- Department of Neurobiology, Maj Institute of Pharmacology, Polish Academy of Sciences, Smętna 12, Kraków, 31-343, Poland.
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Dong J, Dong Y, An L, Wang Y, Li Y, Jin L. The role of the sensory input intervention in recovery of the motor function in hypoxic ischemic encephalopathy rat model. J Neurophysiol 2024; 131:865-871. [PMID: 38568478 DOI: 10.1152/jn.00054.2024] [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: 02/06/2024] [Revised: 03/12/2024] [Accepted: 03/24/2024] [Indexed: 05/01/2024] Open
Abstract
Motor disturbances predominantly characterize hypoxic-ischemic encephalopathy (HIE). Among its intervention methods, environmental enrichment (EE) is strictly considered a form of sensory intervention. However, limited research uses EE as a single sensory input intervention to validate outcomes postintervention. A Sprague-Dawley rat model subjected to left common carotid artery ligation and exposure to oxygen-hypoxic conditions is used in this study. EE was achieved by enhancing the recreational and stress-relief items within the cage, increasing the duration of sunlight, colorful items exposure, and introducing background music. JZL184 (JZL) was administered as neuroprotective drugs. EE was performed 21 days postoperatively and the rats were randomly assigned to the standard environment and EE groups, the two groups were redivided into control, JZL, and vehicle injection subgroups. The Western blotting and behavior test indicated that EE and JZL injections were efficacious in promoting cognitive function in rats following HIE. In addition, the motor function performance in the EE-alone intervention group and the JZL-alone group after HIE was significantly improved compared with the control group. The combined EE and JZL intervention group exhibited even more pronounced improvements in these performances. EE may enhance motor function through sensory input different from the direct neuroprotective effect of pharmacological treatment.NEW & NOTEWORTHY Rarely does literature assess motor function, even though it is common after hypoxia ischemic encephalopathy (HIE). Previously used environmental enrichment (EE) components have not been solely used as sensory inputs. Physical factors were minimized in our study to observe the effects of purely sensory inputs.
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Affiliation(s)
- Juchuan Dong
- Department of Rehabilitation Medicine, Second Affiliated Hospital of Kunming Medical University, Kunming, People's Republic of China
| | - Yifei Dong
- Department of Rehabilitation Medicine, Kunming Medical University, Kunming, People's Republic of China
| | - Lijuan An
- Department of Rehabilitation Medicine, Kunming Medical University, Kunming, People's Republic of China
| | - Yufan Wang
- Department of Rehabilitation Medicine, Kunming Medical University, Kunming, People's Republic of China
| | - Yongmei Li
- Department of Rehabilitation Medicine, Second Affiliated Hospital of Kunming Medical University, Kunming, People's Republic of China
| | - Lihua Jin
- Department of Rehabilitation Medicine, Second Affiliated Hospital of Kunming Medical University, Kunming, People's Republic of China
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Silva NT, Ramírez-Buriticá J, Pritchett DL, Carey MR. Climbing fibers provide essential instructive signals for associative learning. Nat Neurosci 2024; 27:940-951. [PMID: 38565684 PMCID: PMC11088996 DOI: 10.1038/s41593-024-01594-7] [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: 04/18/2022] [Accepted: 02/05/2024] [Indexed: 04/04/2024]
Abstract
Supervised learning depends on instructive signals that shape the output of neural circuits to support learned changes in behavior. Climbing fiber (CF) inputs to the cerebellar cortex represent one of the strongest candidates in the vertebrate brain for conveying neural instructive signals. However, recent studies have shown that Purkinje cell stimulation can also drive cerebellar learning and the relative importance of these two neuron types in providing instructive signals for cerebellum-dependent behaviors remains unresolved. In the present study we used cell-type-specific perturbations of various cerebellar circuit elements to systematically evaluate their contributions to delay eyeblink conditioning in mice. Our findings reveal that, although optogenetic stimulation of either CFs or Purkinje cells can drive learning under some conditions, even subtle reductions in CF signaling completely block learning to natural stimuli. We conclude that CFs and corresponding Purkinje cell complex spike events provide essential instructive signals for associative cerebellar learning.
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Affiliation(s)
- N Tatiana Silva
- Neuroscience Program, Champalimaud Center for the Unknown, Lisbon, Portugal
| | | | - Dominique L Pritchett
- Neuroscience Program, Champalimaud Center for the Unknown, Lisbon, Portugal.
- Biology Department, Howard University, Washington, DC, USA.
| | - Megan R Carey
- Neuroscience Program, Champalimaud Center for the Unknown, Lisbon, Portugal.
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Deshpande K, Martirosian V, Nakamura BN, Das D, Iyer M, Reed M, Shao L, Bamshad D, Buckley NJ, Neman J. SRRM4-mediated REST to REST4 dysregulation promotes tumor growth and neural adaptation in breast cancer leading to brain metastasis. Neuro Oncol 2024; 26:309-322. [PMID: 37716001 PMCID: PMC10836770 DOI: 10.1093/neuonc/noad175] [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: 04/14/2023] [Indexed: 09/18/2023] Open
Abstract
BACKGROUND Effective control of brain metastasis remains an urgent clinical need due a limited understanding of the mechanisms driving it. Although the gain of neuro-adaptive attributes in breast-to-brain metastases (BBMs) has been described, the mechanisms that govern this neural acclimation and the resulting brain metastasis competency are poorly understood. Herein, we define the role of neural-specific splicing factor Serine/Arginine Repetitive Matrix Protein 4 (SRRM4) in regulating microenvironmental adaptation and brain metastasis colonization in breast cancer cells. METHODS Utilizing pure neuronal cultures and brain-naive and patient-derived BM tumor cells, along with in vivo tumor modeling, we surveyed the early induction of mediators of neural acclimation in tumor cells. RESULTS When SRRM4 is overexpressed in systemic breast cancer cells, there is enhanced BBM leading to poorer overall survival in vivo. Concomitantly, SRRM4 knockdown expression does not provide any advantage in central nervous system metastasis. In addition, reducing SRRM4 expression in breast cancer cells slows down proliferation and increases resistance to chemotherapy. Conversely, when SRRM4/REST4 levels are elevated, tumor cell growth is maintained even in nutrient-deprived conditions. In neuronal coculture, decreasing SRRM4 expression in breast cancer cells impairs their ability to adapt to the brain microenvironment, while increasing SRRM4/RE-1 Silencing Transcription Factor (REST4) levels leads to greater expression of neurotransmitter and synaptic signaling mediators and a significant colonization advantage. CONCLUSIONS Collectively, our findings identify SRRM4 as a regulator of brain metastasis colonization, and a potential therapeutic target in breast cancer.
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Affiliation(s)
- Krutika Deshpande
- Department of Neurological Surgery, Keck School of Medicine, University of Southern California, Los Angeles, California, USA
- USC Brain Tumor Center, Keck School of Medicine, University of Southern California, Los Angeles, California, USA)
| | - Vahan Martirosian
- Department of Neurological Surgery, Keck School of Medicine, University of Southern California, Los Angeles, California, USA
- USC Brain Tumor Center, Keck School of Medicine, University of Southern California, Los Angeles, California, USA
| | - Brooke N Nakamura
- Division of Gastrointestinal and Liver Diseases, Department of Medicine, Keck School of Medicine, University of Southern California, Los Angeles, California, USA
- USC Brain Tumor Center, Keck School of Medicine, University of Southern California, Los Angeles, California, USA
| | - Diganta Das
- Department of Neurological Surgery, Keck School of Medicine, University of Southern California, Los Angeles, California, USA
- USC Brain Tumor Center, Keck School of Medicine, University of Southern California, Los Angeles, California, USA
| | - Mukund Iyer
- Department of Neurological Surgery, Keck School of Medicine, University of Southern California, Los Angeles, California, USA
- USC Brain Tumor Center, Keck School of Medicine, University of Southern California, Los Angeles, California, USA
| | - Max Reed
- Department of Neurological Surgery, Keck School of Medicine, University of Southern California, Los Angeles, California, USA
| | - Ling Shao
- Division of Gastrointestinal and Liver Diseases, Department of Medicine, Keck School of Medicine, University of Southern California, Los Angeles, California, USA
| | - Daniella Bamshad
- Department of Neurological Surgery, Keck School of Medicine, University of Southern California, Los Angeles, California, USA
| | - Noel J Buckley
- Department of Psychiatry, University of Oxford, Oxford, UK
| | - Josh Neman
- Department of Neurological Surgery, Keck School of Medicine, University of Southern California, Los Angeles, California, USA
- USC Brain Tumor Center, Keck School of Medicine, University of Southern California, Los Angeles, California, USA
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Tellios V, Maksoud MJE, Nagra R, Jassal G, Lu WY. Neuronal Nitric Oxide Synthase Critically Regulates the Endocannabinoid Pathway in the Murine Cerebellum During Development. CEREBELLUM (LONDON, ENGLAND) 2023; 22:1200-1215. [PMID: 36402869 DOI: 10.1007/s12311-022-01493-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 10/27/2022] [Indexed: 11/21/2022]
Abstract
The cerebellum is a major site of endocannabinoid (eCB) production and signaling. The predominant eCB within the cerebellum, 2-arachidonoylglycerol (2-AG), is produced by a metabotropic glutamate receptor type 1 (mGluR1)-initiated signaling cascade within Purkinje neurons (PNs). 2-AG retrogradely stimulates cannabinoid 1 receptors (CB1Rs) located on presynaptic terminals. The activated CB1R decreases neurotransmitter release and leads to the production of nitric oxide (NO), a gaseous molecule. Recently, our group discovered that during development in mice lacking neuronal nitric oxide synthase (nNOS-/-), PNs display an excitotoxic phenotype associated with overactivated mGluR1. Considering the importance of mGluR1 in 2-AG synthesis, the present study explored the role of nNOS-derived NO in regulating the eCB pathway within the cerebella of wildtype (WT) and nNOS-/- mice at postnatal day 7 (PD7), 2 weeks (2 W), and 7 weeks (7 W). Our analysis showed that diacylglycerol lipase α, the enzyme that catalyzes 2-AG production, was elevated at early postnatal ages, and followed by elevated levels of 2-AG in nNOS-/- cerebella compared to WT. CB1R expression in nNOS-/- cerebella was upregulated at PD7 but decreased at 2 W and 7 W when compared to age-matched WT mice cerebella. Importantly, treating organotypic nNOS-/- cerebellar slice cultures with an NO-donor-attenuated CB1R levels after 7 days in vitro. In addition, expression of the eCB hydrolases fatty acid amide hydrolase and monoacylglycerol lipase were significantly downregulated in nNOS-/- cerebella compared to WT cerebella at 7 W. Together, these results reveal a novel role for nNOS/NO in regulating eCB signaling in the cerebellum.
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Affiliation(s)
- Vasiliki Tellios
- Graduate Program of Neuroscience, The University of Western Ontario, London, N6A 5B7, Canada
- Robarts Research Institute, London, N6A 5B7, Canada
| | - Matthew J E Maksoud
- Graduate Program of Neuroscience, The University of Western Ontario, London, N6A 5B7, Canada
- Robarts Research Institute, London, N6A 5B7, Canada
| | | | - Gurneet Jassal
- Department of Physiology and Pharmacology, The University of Western Ontario, London, N6A 5B7, Canada
| | - Wei-Yang Lu
- Graduate Program of Neuroscience, The University of Western Ontario, London, N6A 5B7, Canada.
- Robarts Research Institute, London, N6A 5B7, Canada.
- Department of Physiology and Pharmacology, The University of Western Ontario, London, N6A 5B7, Canada.
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8
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Kouchaeknejad A, Van Der Walt G, De Donato MH, Puighermanal E. Imaging and Genetic Tools for the Investigation of the Endocannabinoid System in the CNS. Int J Mol Sci 2023; 24:15829. [PMID: 37958825 PMCID: PMC10648052 DOI: 10.3390/ijms242115829] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2023] [Revised: 10/26/2023] [Accepted: 10/27/2023] [Indexed: 11/15/2023] Open
Abstract
As central nervous system (CNS)-related disorders present an increasing cause of global morbidity, mortality, and high pressure on our healthcare system, there is an urgent need for new insights and treatment options. The endocannabinoid system (ECS) is a critical network of endogenous compounds, receptors, and enzymes that contribute to CNS development and regulation. Given its multifaceted involvement in neurobiology and its significance in various CNS disorders, the ECS as a whole is considered a promising therapeutic target. Despite significant advances in our understanding of the ECS's role in the CNS, its complex architecture and extensive crosstalk with other biological systems present challenges for research and clinical advancements. To bridge these knowledge gaps and unlock the full therapeutic potential of ECS interventions in CNS-related disorders, a plethora of molecular-genetic tools have been developed in recent years. Here, we review some of the most impactful tools for investigating the neurological aspects of the ECS. We first provide a brief introduction to the ECS components, including cannabinoid receptors, endocannabinoids, and metabolic enzymes, emphasizing their complexity. This is followed by an exploration of cutting-edge imaging tools and genetic models aimed at elucidating the roles of these principal ECS components. Special emphasis is placed on their relevance in the context of CNS and its associated disorders.
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Affiliation(s)
| | | | | | - Emma Puighermanal
- Neuroscience Institute, Autonomous University of Barcelona, 08193 Bellaterra, Spain; (A.K.); (G.V.D.W.); (M.H.D.D.)
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Lee JH, Khan MM, Stark AP, Seo S, Norton A, Yao Z, Chen CH, Regehr WG. Cerebellar granule cell signaling is indispensable for normal motor performance. Cell Rep 2023; 42:112429. [PMID: 37141091 PMCID: PMC10258556 DOI: 10.1016/j.celrep.2023.112429] [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: 08/17/2022] [Revised: 02/06/2023] [Accepted: 04/07/2023] [Indexed: 05/05/2023] Open
Abstract
Within the cerebellar cortex, mossy fibers (MFs) excite granule cells (GCs) that excite Purkinje cells (PCs), which provide outputs to the deep cerebellar nuclei (DCNs). It is well established that PC disruption produces motor deficits such as ataxia. This could arise from either decreases in ongoing PC-DCN inhibition, increases in the variability of PC firing, or disruption of the flow of MF-evoked signals. Remarkably, it is not known whether GCs are essential for normal motor function. Here we address this issue by selectively eliminating calcium channels that mediate transmission (CaV2.1, CaV2.2, and CaV2.3) in a combinatorial manner. We observe profound motor deficits but only when all CaV2 channels are eliminated. In these mice, the baseline rate and variability of PC firing are unaltered, and locomotion-dependent increases in PC firing are eliminated. We conclude that GCs are indispensable for normal motor performance and that disruption of MF-induced signals impairs motor performance.
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Affiliation(s)
- Joon-Hyuk Lee
- Department of Neurobiology, Harvard Medical School, Boston, MA 02115, USA
| | - Mehak M Khan
- Department of Neurobiology, Harvard Medical School, Boston, MA 02115, USA
| | - Amanda P Stark
- Department of Neurobiology, Harvard Medical School, Boston, MA 02115, USA
| | - Soobin Seo
- Department of Neurobiology, Harvard Medical School, Boston, MA 02115, USA
| | - Aliya Norton
- Department of Neurobiology, Harvard Medical School, Boston, MA 02115, USA
| | - Zhiyi Yao
- Department of Neurobiology, Harvard Medical School, Boston, MA 02115, USA
| | - Christopher H Chen
- Department of Neurobiology, Harvard Medical School, Boston, MA 02115, USA
| | - Wade G Regehr
- Department of Neurobiology, Harvard Medical School, Boston, MA 02115, USA.
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CBD supplementation reduces arterial blood pressure via modulation of the sympatho-chromaffin system: A substudy from the HYPER-H21-4 trial. Biomed Pharmacother 2023; 160:114387. [PMID: 36780785 DOI: 10.1016/j.biopha.2023.114387] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2022] [Revised: 01/31/2023] [Accepted: 02/07/2023] [Indexed: 02/13/2023] Open
Abstract
Data concerning the effects of cannabidiol (CBD) on blood pressure (BP) is controversial. HYPER-H21-4 was a randomized, placebo-controlled, crossover trial which sought to elucidate if 5-week administration of CBD will reduce BP in hypertensive patients. In the substudy of this trial, we aimed to establish the mechanistic background of CBD-induced BP reduction. Specifically, we explored the dynamic of catestatin, a sympathoinhibitory peptide implicated in the pathophysiology of hypertension. In the present analysis, 54 patients with Grade 1 hypertension were included. 5-week administration of CBD but not placebo reduced serum catestatin concentration in comparison to baseline (13.50 [10.85-19.05] vs. 9.65 [6.37-12.26] ng/mL, p < 0.001). Serum catestatin levels at the start of the treatment period demonstrated a negative correlation with the extent of reduction in mean arterial pressure (r = -0.474, p < 0.001). Moreover, the extent of change in catestatin serum levels showed a strong correlation with the extent of mean arterial pressure reduction (r = 0.712, p < 0.001). Overall, the results of the present study imply that the antihypertensive effects of CBD may be explained by its interaction with the sympatho-chromaffin system, although further research is warranted.
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Zhang S, Morrison J, Wang W, Greene E. Recognition of letters displayed as successive contour fragments. AIMS Neurosci 2022; 9:491-515. [PMID: 36660071 PMCID: PMC9826752 DOI: 10.3934/neuroscience.2022028] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2022] [Revised: 12/01/2022] [Accepted: 12/04/2022] [Indexed: 12/14/2022] Open
Abstract
Shapes can be displayed as parts but perceived as a whole through feedforward and feedback mechanisms in the visual system, though the exact spatiotemporal relationships for this process are still unclear. Our experiments examined the integration of letter fragments that were displayed as a rapid sequence. We examined the effects of timing and masking on integration, hypothesizing that increasing the timing interval between frames would impair recognition by disrupting contour linkage. We further used different mask types, a full-field pattern mask and a smaller strip mask, to examine the effects of global vs local masking on integration. We found that varying mask types and contrast produced a greater decline in recognition than was found when persistence or mask density was manipulated. The study supports prior work on letter recognition and provides greater insight into the spatiotemporal factors that contribute to the identification of shapes.
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Affiliation(s)
- Sherry Zhang
- Department of Psychology, University of Southern California, Los Angeles, CA 90007, United States of America,* Correspondence:
| | - Jack Morrison
- Neuropsychology Foundation, Sun Valley, CA 91353, United States of America
| | - Wei Wang
- Departments of Medicine and Neurology, Brigham and Women's Hospital. Division of Sleep Medicine, Harvard Medical School, Boston, MA 02115, United States of America
| | - Ernest Greene
- Department of Psychology, University of Southern California, Los Angeles, CA 90007, United States of America
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12
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Zhao J, Zhang H, Fan X, Yu X, Huai J. Lipid Dyshomeostasis and Inherited Cerebellar Ataxia. Mol Neurobiol 2022; 59:3800-3828. [PMID: 35420383 PMCID: PMC9148275 DOI: 10.1007/s12035-022-02826-2] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2021] [Accepted: 04/01/2022] [Indexed: 12/04/2022]
Abstract
Cerebellar ataxia is a form of ataxia that originates from dysfunction of the cerebellum, but may involve additional neurological tissues. Its clinical symptoms are mainly characterized by the absence of voluntary muscle coordination and loss of control of movement with varying manifestations due to differences in severity, in the site of cerebellar damage and in the involvement of extracerebellar tissues. Cerebellar ataxia may be sporadic, acquired, and hereditary. Hereditary ataxia accounts for the majority of cases. Hereditary ataxia has been tentatively divided into several subtypes by scientists in the field, and nearly all of them remain incurable. This is mainly because the detailed mechanisms of these cerebellar disorders are incompletely understood. To precisely diagnose and treat these diseases, studies on their molecular mechanisms have been conducted extensively in the past. Accumulating evidence has demonstrated that some common pathogenic mechanisms exist within each subtype of inherited ataxia. However, no reports have indicated whether there is a common mechanism among the different subtypes of inherited cerebellar ataxia. In this review, we summarize the available references and databases on neurological disorders characterized by cerebellar ataxia and show that a subset of genes involved in lipid homeostasis form a new group that may cause ataxic disorders through a common mechanism. This common signaling pathway can provide a valuable reference for future diagnosis and treatment of ataxic disorders.
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Affiliation(s)
- Jin Zhao
- The Second Affiliated Hospital of Xinxiang Medical University (Henan Mental Hospital), Xinxiang, 453000, China
- Institute of Psychiatry and Neuroscience, Xinxiang Medical University, Xinxiang, 453003, China
| | - Huan Zhang
- The Second Affiliated Hospital of Xinxiang Medical University (Henan Mental Hospital), Xinxiang, 453000, China
- Institute of Psychiatry and Neuroscience, Xinxiang Medical University, Xinxiang, 453003, China
| | - Xueyu Fan
- The Second Affiliated Hospital of Xinxiang Medical University (Henan Mental Hospital), Xinxiang, 453000, China
- Institute of Psychiatry and Neuroscience, Xinxiang Medical University, Xinxiang, 453003, China
| | - Xue Yu
- The Second Affiliated Hospital of Xinxiang Medical University (Henan Mental Hospital), Xinxiang, 453000, China
- Institute of Psychiatry and Neuroscience, Xinxiang Medical University, Xinxiang, 453003, China
| | - Jisen Huai
- The Second Affiliated Hospital of Xinxiang Medical University (Henan Mental Hospital), Xinxiang, 453000, China.
- Institute of Psychiatry and Neuroscience, Xinxiang Medical University, Xinxiang, 453003, China.
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13
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Winters BL, Vaughan CW. Mechanisms of endocannabinoid control of synaptic plasticity. Neuropharmacology 2021; 197:108736. [PMID: 34343612 DOI: 10.1016/j.neuropharm.2021.108736] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2021] [Revised: 07/27/2021] [Accepted: 07/28/2021] [Indexed: 01/13/2023]
Abstract
The endogenous cannabinoid transmitter system regulates synaptic transmission throughout the nervous system. Unlike conventional transmitters, specific stimuli induce synthesis of endocannabinoids (eCBs) in the postsynaptic neuron, and these travel backwards to modulate presynaptic inputs. In doing so, eCBs can induce short-term changes in synaptic strength and longer-term plasticity. While this eCB regulation is near ubiquitous, it displays major regional and synapse specific variations with different synapse specific forms of short-versus long-term plasticity throughout the brain. These differences are due to the plethora of pre- and postsynaptic mechanisms which have been implicated in eCB signalling, the intricacies of which are only just being realised. In this review, we shall describe the current understanding and highlight new advances in this area, with a focus on the retrograde action of eCBs at CB1 receptors (CB1Rs).
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Affiliation(s)
- Bryony Laura Winters
- Pain Management Research Institute, Kolling Institute of Medical Research, Northern Clinical School, University of Sydney at Royal North Shore Hospital, NSW, Australia.
| | - Christopher Walter Vaughan
- Pain Management Research Institute, Kolling Institute of Medical Research, Northern Clinical School, University of Sydney at Royal North Shore Hospital, NSW, Australia
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14
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Albergaria C, Silva NT, Darmohray DM, Carey MR. Cannabinoids modulate associative cerebellar learning via alterations in behavioral state. eLife 2020; 9:61821. [PMID: 33077026 PMCID: PMC7575324 DOI: 10.7554/elife.61821] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2020] [Accepted: 10/01/2020] [Indexed: 02/06/2023] Open
Abstract
Cannabinoids are notorious and profound modulators of behavioral state. In the brain, endocannabinoids act via Type 1-cannabinoid receptors (CB1) to modulate synaptic transmission and mediate multiple forms of synaptic plasticity. CB1 knockout (CB1KO) mice display a range of behavioral phenotypes, in particular hypoactivity and various deficits in learning and memory, including cerebellum-dependent delay eyeblink conditioning. Here we find that the apparent effects of CB1 deletion on cerebellar learning are not due to direct effects on CB1-dependent plasticity, but rather, arise as a secondary consequence of altered behavioral state. Hypoactivity of CB1KO mice accounts for their impaired eyeblink conditioning across both animals and trials. Moreover, learning in these mutants is rescued by walking on a motorized treadmill during training. Finally, cerebellar granule-cell-specific CB1KOs exhibit normal eyeblink conditioning, and both global and granule-cell-specific CB1KOs display normal cerebellum-dependent locomotor coordination and learning. These findings highlight the modulation of behavioral state as a powerful independent means through which individual genes contribute to complex behaviors.
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Affiliation(s)
- Catarina Albergaria
- Champalimaud Neuroscience Program, Champalimaud Center for the Unknown, Lisbon, Portugal
| | - N Tatiana Silva
- Champalimaud Neuroscience Program, Champalimaud Center for the Unknown, Lisbon, Portugal
| | - Dana M Darmohray
- Champalimaud Neuroscience Program, Champalimaud Center for the Unknown, Lisbon, Portugal
| | - Megan R Carey
- Champalimaud Neuroscience Program, Champalimaud Center for the Unknown, Lisbon, Portugal
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15
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Canepari M. Is Purkinje Neuron Hyperpolarisation Important for Cerebellar Synaptic Plasticity? A Retrospective and Prospective Analysis. THE CEREBELLUM 2020; 19:869-878. [PMID: 32654026 DOI: 10.1007/s12311-020-01164-0] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Two recent studies have demonstrated that the dendritic Ca2+ signal associated with a climbing fibre (CF) input to the cerebellar Purkinje neuron (PN) depends on the membrane potential (Vm). Specifically, when the cell is hyperpolarised, this signal is mediated by T-type voltage-gated Ca2+ channels; in contrast, when the cell is firing, the CF-PN signal is mediated by P/Q-type voltage-gated Ca2+ channels. When the CF input is paired with parallel fibre (PF) activity, the signal is locally amplified at the sites of PF-activated synapses according to the Vm at the time of the CF input, suggesting that the standing Vm is a critical parameter for the induction of PF synaptic plasticity. In this review, I analyse how the Vm can potentially play a role in cerebellar learning focussing, in particular, on the hyperpolarised state that appears to occur episodically, since PNs are mostly firing under physiological conditions. By revisiting the recent literature reporting in vivo recordings and synaptic plasticity studies, I speculate on how a putative role of the PN Vm can provide an interpretation for the results of these studies.
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Affiliation(s)
- Marco Canepari
- University of Grenoble Alpes, CNRS, LIPhy, F-38000, Grenoble, France. .,Laboratories of Excellence, Ion Channel Science and Therapeutics, Valbonne, France. .,Institut National de la Santé et Recherche Médicale, Paris, France.
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16
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Sadanandan SM, Kreko-Pierce T, Khatri SN, Pugh JR. Cannabinoid type 2 receptors inhibit GABAA receptor-mediated currents in cerebellar Purkinje cells of juvenile mice. PLoS One 2020; 15:e0233020. [PMID: 32437355 PMCID: PMC7241750 DOI: 10.1371/journal.pone.0233020] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2019] [Accepted: 04/28/2020] [Indexed: 12/15/2022] Open
Abstract
Signaling through the endocannabinoid system is critical to proper functioning of the cerebellar circuit. However, most studies have focused on signaling through cannabinoid type 1 (CB1) receptors, while relatively little is known about signaling through type 2 (CB2) receptors. We show that functional CB2 receptors are expressed in Purkinje cells using a combination of immunohistochemistry and patch-clamp electrophysiology in juvenile mice. Pharmacological activation of CB2 receptors significantly reduces inhibitory synaptic responses and currents mediated by photolytic uncaging of RuBi-GABA in Purkinje cells. CB2 receptor activation does not change the paired-pulse ratio of inhibitory responses and its effects are blocked by inclusion of GDP-β-S in the internal solution, indicating a postsynaptic mechanism of action. However, CB2 receptors do not contribute to depolarization induced suppression of inhibition (DSI), indicating they are not activated by endocannabinoids synthesized and released from Purkinje cells using this protocol. This work demonstrates that CB2 receptors inhibit postsynaptic GABAA receptors by a postsynaptic mechanism in Purkinje cells. This represents a novel mechanism by which CB2 receptors may modulate neuronal and circuit function in the central nervous system.
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Affiliation(s)
- Sriity Melley Sadanandan
- Department of Cellular and Integrative Physiology, University of Texas Health Science Center at San Antonio, San Antonio, TX, United States of America
| | - Tabita Kreko-Pierce
- Department of Cellular and Integrative Physiology, University of Texas Health Science Center at San Antonio, San Antonio, TX, United States of America
| | - Shailesh N. Khatri
- Department of Cellular and Integrative Physiology, University of Texas Health Science Center at San Antonio, San Antonio, TX, United States of America
| | - Jason R. Pugh
- Department of Cellular and Integrative Physiology, University of Texas Health Science Center at San Antonio, San Antonio, TX, United States of America
- Center for Biomedical Neuroscience, University of Texas Health Science Center at San Antonio, San Antonio, Texas, United States of America
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17
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Martinez LR, Black KC, Webb BT, Bell A, Baygani SK, Mier TJ, Dominguez L, Mackie K, Kalinovsky A. Components of Endocannabinoid Signaling System Are Expressed in the Perinatal Mouse Cerebellum and Required for Its Normal Development. eNeuro 2020; 7:ENEURO.0471-19.2020. [PMID: 32179579 PMCID: PMC7189485 DOI: 10.1523/eneuro.0471-19.2020] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2019] [Revised: 02/26/2020] [Accepted: 02/28/2020] [Indexed: 11/21/2022] Open
Abstract
Endocannabinoid (eCB) signaling system (ECS), encompassing cannabinoid receptors and enzymes involved in the synthesis and degradation of the endogenous cannabinoid signaling lipids, is highly expressed in the cerebellar cortex of adult humans and rodents. In addition to their well-established role in neuromodulation, eCBs have been shown to play key roles in aspects of neurodevelopment in the fore- and mid-brain, including neurogenesis, cell migration, and synapse specification. However, little is known about the role of ECS in cerebellar development. In this study, we conducted immunohistochemical characterization of ECS components through key stages of cerebellar development in mice using antibodies for 2-arachidonoylglycerol (2-AG) synthetizing and degrading enzymes and the major brain cannabinoid receptor, cannabinoid receptor 1 (CB1), in combination with cerebellar cell markers. Our results reveal a temporally, spatially, and cytologically dynamic pattern of expression. Production, receptor binding, and degradation of eCBs are tightly controlled, thus localization of eCB receptors and the complementary cannabinoid signaling machinery determines the direction, duration, and ultimately the outcome of eCB signaling. To gain insights into the role of eCB signaling in cerebellar development, we characterized gross anatomy of cerebellar midvermis in CB1 knock-out (CB1 KO) mice, as well as their performance in cerebellar-influenced motor tasks. Our results show persistent and selective anatomic and behavioral alterations in CB1 KOs. Consequently, the insights gained from this study lay down the foundation for investigating specific cellular and molecular mechanisms regulated by eCB signaling during cerebellar development.
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Affiliation(s)
- Luis Ricardo Martinez
- The Gill Center for Biomolecular Science, Program in Neuroscience, Department of Psychological and Brain Sciences, Indiana University, Bloomington, 47405 IN
| | - Kylie Caroline Black
- The Gill Center for Biomolecular Science, Program in Neuroscience, Department of Psychological and Brain Sciences, Indiana University, Bloomington, 47405 IN
| | - Brynna Tellas Webb
- The Gill Center for Biomolecular Science, Program in Neuroscience, Department of Psychological and Brain Sciences, Indiana University, Bloomington, 47405 IN
| | - Alexandria Bell
- The Gill Center for Biomolecular Science, Program in Neuroscience, Department of Psychological and Brain Sciences, Indiana University, Bloomington, 47405 IN
| | - Shawyon Kevin Baygani
- The Gill Center for Biomolecular Science, Program in Neuroscience, Department of Psychological and Brain Sciences, Indiana University, Bloomington, 47405 IN
| | - Tristen Jay Mier
- The Gill Center for Biomolecular Science, Program in Neuroscience, Department of Psychological and Brain Sciences, Indiana University, Bloomington, 47405 IN
| | - Luis Dominguez
- The Gill Center for Biomolecular Science, Program in Neuroscience, Department of Psychological and Brain Sciences, Indiana University, Bloomington, 47405 IN
| | - Ken Mackie
- The Gill Center for Biomolecular Science, Program in Neuroscience, Department of Psychological and Brain Sciences, Indiana University, Bloomington, 47405 IN
| | - Anna Kalinovsky
- The Gill Center for Biomolecular Science, Program in Neuroscience, Department of Psychological and Brain Sciences, Indiana University, Bloomington, 47405 IN
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18
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Hull C. Prediction signals in the cerebellum: beyond supervised motor learning. eLife 2020; 9:54073. [PMID: 32223891 PMCID: PMC7105376 DOI: 10.7554/elife.54073] [Citation(s) in RCA: 87] [Impact Index Per Article: 21.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2019] [Accepted: 03/09/2020] [Indexed: 12/22/2022] Open
Abstract
While classical views of cerebellar learning have suggested that this structure predominantly operates according to an error-based supervised learning rule to refine movements, emerging evidence suggests that the cerebellum may also harness a wider range of learning rules to contribute to a variety of behaviors, including cognitive processes. Together, such evidence points to a broad role for cerebellar circuits in generating and testing predictions about movement, reward, and other non-motor operations. However, this expanded view of cerebellar processing also raises many new questions about how such apparent diversity of function arises from a structure with striking homogeneity. Hence, this review will highlight both current evidence for predictive cerebellar circuit function that extends beyond the classical view of error-driven supervised learning, as well as open questions that must be addressed to unify our understanding cerebellar circuit function.
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Affiliation(s)
- Court Hull
- Department of Neurobiology, Duke University School of Medicine, Durham, United States
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19
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Buceta I, Elezgarai I, Rico‐Barrio I, Gerrikagoitia I, Puente N, Grandes P. Deletion of the cannabinoid CB
1
receptor impacts on the ultrastructure of the cerebellar parallel fiber‐Purkinje cell synapses. J Comp Neurol 2019; 528:1041-1052. [DOI: 10.1002/cne.24808] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2019] [Revised: 10/09/2019] [Accepted: 10/31/2019] [Indexed: 12/15/2022]
Affiliation(s)
- Ianire Buceta
- Department of Neurosciences, Faculty of Medicine and Nursing University of the Basque Country UPV/EHU Leioa Spain
- Achucarro Basque Center for Neuroscience Science Park of the University of the Basque Country UPV/EHU Leioa Spain
| | - Izaskun Elezgarai
- Department of Neurosciences, Faculty of Medicine and Nursing University of the Basque Country UPV/EHU Leioa Spain
- Achucarro Basque Center for Neuroscience Science Park of the University of the Basque Country UPV/EHU Leioa Spain
| | - Irantzu Rico‐Barrio
- Department of Neurosciences, Faculty of Medicine and Nursing University of the Basque Country UPV/EHU Leioa Spain
- Achucarro Basque Center for Neuroscience Science Park of the University of the Basque Country UPV/EHU Leioa Spain
| | - Inmaculada Gerrikagoitia
- Department of Neurosciences, Faculty of Medicine and Nursing University of the Basque Country UPV/EHU Leioa Spain
- Achucarro Basque Center for Neuroscience Science Park of the University of the Basque Country UPV/EHU Leioa Spain
| | - Nagore Puente
- Department of Neurosciences, Faculty of Medicine and Nursing University of the Basque Country UPV/EHU Leioa Spain
- Achucarro Basque Center for Neuroscience Science Park of the University of the Basque Country UPV/EHU Leioa Spain
| | - Pedro Grandes
- Department of Neurosciences, Faculty of Medicine and Nursing University of the Basque Country UPV/EHU Leioa Spain
- Achucarro Basque Center for Neuroscience Science Park of the University of the Basque Country UPV/EHU Leioa Spain
- Division of Medical Sciences University of Victoria Victoria British Columbia Canada
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20
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Yang Y, Kreko-Pierce T, Howell R, Pugh JR. Long-term depression of presynaptic cannabinoid receptor function at parallel fibre synapses. J Physiol 2019; 597:3167-3181. [PMID: 31020998 DOI: 10.1113/jp277727] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2019] [Accepted: 04/18/2019] [Indexed: 12/22/2022] Open
Abstract
KEY POINTS Inhibition of synaptic responses by activation of presynaptic cannabinoid type-1 (Cb1) receptors is reduced at parallel fibre synapses in the cerebellum following 4 Hz stimulation. Activation of adenylyl cyclase is necessary and sufficient for down-regulation of Cb1 receptors induced by 4 Hz stimulation. 4 Hz stimulation reduces Cb1 receptor function by (i) increasing the rate of endocannabinoid clearance from the synapse and (ii) decreasing expression of Cb1 receptors. ABSTRACT Cannabinoid type-1 receptors (Cb1R) are expressed in the presynaptic membrane of many synapses, including parallel fibre-Purkinje cell synapses in the cerebellum, where they are involved in short- and long-term plasticity of synaptic responses. We show that Cb1R expression itself is a plastic property of the synapse regulated by physiological activity patterns. We made patch clamp recordings from Purkinje cells in cerebellar slices and assessed Cb1R activity by measuring depolarization-induced suppression of excitation (DSE). We find that DSE is normally stable at parallel fibre synapses but, following 4 Hz stimulation, DSE is persistently reduced and recovers more rapidly. Using a combination of electrophysiology, pharmacology and biochemistry, we show that changes in DSE are a result of the reduced expression of Cb1Rs and increased degradation of endocannabinoids by monoacylglycerol lipase. Long-term changes in presynaptic Cb1R expression may alter other forms of Cb1R-dependent plasticity at parallel fibre synapses, priming or inhibiting the circuit for associative learning.
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Affiliation(s)
- Ying Yang
- University of Texas Health Science Center at San Antonio, Department of Cellular and Integrative Physiology, San Antonio, TX, USA.,Xiangya School of Medicine, Department of Pain, The Third Xiangya Hospital and Institute of Pain Medicine, Central South University, Changsha, Hunan Province, China
| | - Tabita Kreko-Pierce
- University of Texas Health Science Center at San Antonio, Department of Cellular and Integrative Physiology, San Antonio, TX, USA
| | - Rebecca Howell
- University of Texas Health Science Center at San Antonio, Department of Cellular and Integrative Physiology, San Antonio, TX, USA.,Present address: Oklahoma Medical Research Foundation & University of Oklahoma Health Science Center, Oklahoma City, OK, USA
| | - Jason R Pugh
- University of Texas Health Science Center at San Antonio, Department of Cellular and Integrative Physiology, San Antonio, TX, USA.,Center for Biomedical Neuroscience, University of Texas Health Science Center at San Antonio, San Antonio, TX, USA
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21
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Suvrathan A, Raymond JL. Depressed by Learning-Heterogeneity of the Plasticity Rules at Parallel Fiber Synapses onto Purkinje Cells. CEREBELLUM (LONDON, ENGLAND) 2018; 17:747-755. [PMID: 30069835 PMCID: PMC6550343 DOI: 10.1007/s12311-018-0968-8] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
Climbing fiber-driven long-term depression (LTD) of parallel fiber synapses onto cerebellar Purkinje cells has long been investigated as a putative mechanism of motor learning. We recently discovered that the rules governing the induction of LTD at these synapses vary across different regions of the cerebellum. Here, we discuss the design of LTD induction protocols in light of this heterogeneity in plasticity rules. The analytical advantages of the cerebellum provide an opportunity to develop a deeper understanding of how the specific plasticity rules at synapses support the implementation of learning.
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Affiliation(s)
- Aparna Suvrathan
- Centre for Research in Neuroscience, Department of Neurology and Neurosurgery, Department of Pediatrics, Brain Repair and Integrative Neuroscience Program, the Research Institute of the McGill University Health Centre, McGill University, Montréal General Hospital, Montréal, Quebec, H3G 1A4, Canada
| | - Jennifer L Raymond
- Department of Neurobiology, Stanford University, Stanford, CA, 94305, USA.
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22
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Boggs DL, Cortes-Briones JA, Surti T, Luddy C, Ranganathan M, Cahill JD, Sewell AR, D'Souza DC, Skosnik PD. The dose-dependent psychomotor effects of intravenous delta-9-tetrahydrocannabinol (Δ 9-THC) in humans. J Psychopharmacol 2018; 32:1308-1318. [PMID: 30255720 DOI: 10.1177/0269881118799953] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
BACKGROUND Binding studies have demonstrated that levels of the cannabinoid receptor type-1 are highest in the basal ganglia and cerebellum, two areas critical for motor control. However, no studies have systematically examined the dose-related effects of intravenous delta-9-tetrahydrocannabinol, the primary cannabinoid receptor type-1 partial agonist in cannabis, on broad domains of psychomotor function in humans. AIMS Therefore, three domains of psychomotor function were assessed in former cannabis users (cannabis abstinent for a minimum of three months; n=23) in a three test-day, within-subject, double-blind, randomized, cross-over, and counterbalanced study during which they received intravenous delta-9-tetrahydrocannabinol (placebo, 0.015 mg/kg, and 0.03 mg/kg). METHODS Gross motor function was assessed via the Cambridge Neuropsychological Test Automated Battery Motor Screening Task, fine motor control via the Lafayette Instrument Grooved Pegboard task, and motor timing via a Paced Finger-Tapping Task. In addition, the Cambridge Neuropsychological Test Automated Battery Rapid Visual Processing Task was utilized to determine whether delta-9-tetrahydrocannabinol-induced motor deficits were confounded by disruptions in sustained attention. RESULTS/OUTCOMES Delta-9-tetrahydrocannabinol resulted in robust dose-dependent deficits in fine motor control (Grooved Pegboard Task) and motor timing (Paced Finger-Tapping Task), while gross motor performance (Motor Screening Task) and sustained attention (Rapid Visual Processing Task) were unimpaired. Interestingly, despite the observed dose-dependent increases in motor impairment and blood levels of delta-9-tetrahydrocannabinol, subjects reported similar levels of intoxication in the two drug conditions. CONCLUSIONS/INTERPRETATION These data suggest that while several domains of motor function are disrupted by delta-9-tetrahydrocannabinol, subjective feelings of intoxication are dissociable from cannabinoid-induced psychomotor effects. Results are discussed in terms of the potential neural mechanisms of delta-9-tetrahydrocannabinol in motor structures.
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Affiliation(s)
- Douglas L Boggs
- 1 Department of Psychiatry, Yale University School of Medicine, West Haven, CT, USA.,2 Psychiatry Service, VA Connecticut Healthcare System, West Haven, CT, USA
| | - Jose A Cortes-Briones
- 1 Department of Psychiatry, Yale University School of Medicine, West Haven, CT, USA.,2 Psychiatry Service, VA Connecticut Healthcare System, West Haven, CT, USA
| | - Toral Surti
- 1 Department of Psychiatry, Yale University School of Medicine, West Haven, CT, USA.,2 Psychiatry Service, VA Connecticut Healthcare System, West Haven, CT, USA
| | - Christina Luddy
- 1 Department of Psychiatry, Yale University School of Medicine, West Haven, CT, USA.,2 Psychiatry Service, VA Connecticut Healthcare System, West Haven, CT, USA
| | - Mohini Ranganathan
- 1 Department of Psychiatry, Yale University School of Medicine, West Haven, CT, USA.,2 Psychiatry Service, VA Connecticut Healthcare System, West Haven, CT, USA
| | - John D Cahill
- 1 Department of Psychiatry, Yale University School of Medicine, West Haven, CT, USA.,2 Psychiatry Service, VA Connecticut Healthcare System, West Haven, CT, USA
| | - Andrew R Sewell
- 1 Department of Psychiatry, Yale University School of Medicine, West Haven, CT, USA.,2 Psychiatry Service, VA Connecticut Healthcare System, West Haven, CT, USA
| | - Deepak C D'Souza
- 1 Department of Psychiatry, Yale University School of Medicine, West Haven, CT, USA.,2 Psychiatry Service, VA Connecticut Healthcare System, West Haven, CT, USA
| | - Patrick D Skosnik
- 1 Department of Psychiatry, Yale University School of Medicine, West Haven, CT, USA.,2 Psychiatry Service, VA Connecticut Healthcare System, West Haven, CT, USA
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23
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Augustin SM, Lovinger DM. Functional Relevance of Endocannabinoid-Dependent Synaptic Plasticity in the Central Nervous System. ACS Chem Neurosci 2018; 9:2146-2161. [PMID: 29400439 DOI: 10.1021/acschemneuro.7b00508] [Citation(s) in RCA: 66] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
The endocannabinoid (eCB) signaling system plays a key role in short-term and long-term synaptic plasticity in brain regions involved in various neural functions ranging from action selection to appetite control. This review will explore the role of eCBs in shaping neural circuit function to regulate behaviors. In particular, we will discuss the behavioral consequences of eCB mediated long-term synaptic plasticity in different brain regions. This review brings together evidence from in vitro and ex vivo studies and points out the need for more in vivo studies.
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Affiliation(s)
- Shana M. Augustin
- Laboratory for Integrative Neuroscience, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Rockville, Maryland 20852, United States
| | - David M. Lovinger
- Laboratory for Integrative Neuroscience, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Rockville, Maryland 20852, United States
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24
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Locomotor activity modulates associative learning in mouse cerebellum. Nat Neurosci 2018; 21:725-735. [PMID: 29662214 PMCID: PMC5923878 DOI: 10.1038/s41593-018-0129-x] [Citation(s) in RCA: 60] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2016] [Accepted: 03/01/2018] [Indexed: 11/26/2022]
Abstract
Changes in behavioral state can profoundly influence brain function. Here we show that behavioral state modulates performance in delay eyeblink conditioning, a cerebellum-dependent form of associative learning. Increased locomotor speed in head-fixed mice drove earlier onset of learning and trial-by-trial enhancement of learned responses that were dissociable from changes in arousal and independent of sensory modality. Eyelid responses evoked by optogenetic stimulation of mossy fiber inputs to the cerebellum, but not at sites downstream, were positively modulated by ongoing locomotion. Substituting prolonged, low-intensity optogenetic mossy fiber stimulation for locomotion was sufficient to enhance conditioned responses. Our results suggest that locomotor activity modulates delay eyeblink conditioning through increased activation of the mossy fiber pathway within the cerebellum. Taken together, these results provide evidence for a novel role for behavioral state modulation in associative learning and suggest a potential mechanism through which engaging in movement can improve an individual’s ability to learn.
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25
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Changes in the cannabinoids receptors in rats following treatment with antidepressants. Neurotoxicology 2017; 63:13-20. [DOI: 10.1016/j.neuro.2017.08.012] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2017] [Revised: 07/17/2017] [Accepted: 08/24/2017] [Indexed: 11/23/2022]
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26
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Alonso B, Bartolomé-Martín D, Ferrero JJ, Ramírez-Franco J, Torres M, Sánchez-Prieto J. CB1 receptors down-regulate a cAMP/Epac2/PLC pathway to silence the nerve terminals of cerebellar granule cells. J Neurochem 2017; 142:350-364. [PMID: 28445587 DOI: 10.1111/jnc.14059] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2017] [Revised: 04/19/2017] [Accepted: 04/19/2017] [Indexed: 01/06/2023]
Abstract
Cannabinoid receptors mediate short-term retrograde inhibition of neurotransmitter release, as well as long-term depression of synaptic transmission at excitatory synapses. The responses of individual nerve terminals in VGLUT1-pHluorin transfected cerebellar granule cells to cannabinoids have shown that prolonged activation of cannabinoid type 1 receptors (CB1Rs) silences a subpopulation of previously active synaptic boutons. Adopting a combined pharmacological and genetic approach to study the molecular mechanisms of CB1R-induced silencing, we found that adenylyl cyclase inhibition decreases cAMP levels while it increases the number of silent synaptic boutons and occludes the induction of further silencing by the cannabinoid agonist HU-210. Guanine nucleotide exchange proteins directly activated by cAMP (Epac proteins) mediate some of the presynaptic effects of cAMP in the potentiation of synaptic transmission. ESI05, a selective Epac2 inhibitor, and U-73122, the specific inhibitor of phospholipase C (PLC), both augment the number of silent synaptic boutons. Moreover, they abolish the capacity of the Epac activator, 8-(4-chlorophenylthio)-2'-O-methyladenosine 3',5'-cyclic monophosphate monosodium hydrate, to prevent HU-210-induced silencing consistent with PLC signaling lying downstream of Epac2 proteins. Furthermore, Rab3-interacting molecule (RIM)1α KO cells have many more basally silent synaptic boutons (12.9 ± 3.5%) than wild-type cells (1.1 ± 0.5%). HU-210 induced further silencing in these mutant cells, although 8-(4-chlorophenylthio)-2'-O-methyladenosine 3',5'-cyclic monophosphate monosodium hydrate only awoke the HU-210-induced silence and not the basally silent synaptic boutons. This behavior can be rescued by expressing RIM1α in RIM1α KO cells, these cells behaving very much like wild-type cells. These findings support the hypothesis that a cAMP/Epac/PLC signaling pathway targeting the release machinery appears to mediate cannabinoid-induced presynaptic silencing.
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Affiliation(s)
- Beatris Alonso
- Departamento de Bioquímica, Facultad de Veterinaria, Universidad Complutense, Madrid, Spain.,Instituto de Investigación Sanitaria del Hospital Clínico San Carlos, Madrid, Spain
| | - David Bartolomé-Martín
- Departamento de Bioquímica, Facultad de Veterinaria, Universidad Complutense, Madrid, Spain.,Instituto de Investigación Sanitaria del Hospital Clínico San Carlos, Madrid, Spain
| | - José Javier Ferrero
- Departamento de Bioquímica, Facultad de Veterinaria, Universidad Complutense, Madrid, Spain.,Instituto de Investigación Sanitaria del Hospital Clínico San Carlos, Madrid, Spain
| | - Jorge Ramírez-Franco
- Departamento de Bioquímica, Facultad de Veterinaria, Universidad Complutense, Madrid, Spain.,Instituto de Investigación Sanitaria del Hospital Clínico San Carlos, Madrid, Spain
| | - Magdalena Torres
- Departamento de Bioquímica, Facultad de Veterinaria, Universidad Complutense, Madrid, Spain.,Instituto de Investigación Sanitaria del Hospital Clínico San Carlos, Madrid, Spain
| | - José Sánchez-Prieto
- Departamento de Bioquímica, Facultad de Veterinaria, Universidad Complutense, Madrid, Spain.,Instituto de Investigación Sanitaria del Hospital Clínico San Carlos, Madrid, Spain
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27
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Endocannabinoid modulation of dopamine neurotransmission. Neuropharmacology 2017; 124:52-61. [PMID: 28450060 DOI: 10.1016/j.neuropharm.2017.04.033] [Citation(s) in RCA: 117] [Impact Index Per Article: 16.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2017] [Revised: 04/20/2017] [Accepted: 04/23/2017] [Indexed: 12/15/2022]
Abstract
Dopamine (DA) is a major catecholamine neurotransmitter in the mammalian brain that controls neural circuits involved in the cognitive, emotional, and motor aspects of goal-directed behavior. Accordingly, perturbations in DA neurotransmission play a central role in several neuropsychiatric disorders. Somewhat surprisingly given its prominent role in numerous behaviors, DA is released by a relatively small number of densely packed neurons originating in the midbrain. The dopaminergic midbrain innervates numerous brain regions where extracellular DA release and receptor binding promote short- and long-term changes in postsynaptic neuron function. Striatal forebrain nuclei receive the greatest proportion of DA projections and are a predominant hub at which DA influences behavior. A number of excitatory, inhibitory, and modulatory inputs orchestrate DA neurotransmission by controlling DA cell body firing patterns, terminal release, and effects on postsynaptic sites in the striatum. The endocannabinoid (eCB) system serves as an important filter of afferent input that acts locally at midbrain and terminal regions to shape how incoming information is conveyed onto DA neurons and to output targets. In this review, we aim to highlight existing knowledge regarding how eCB signaling controls DA neuron function through modifications in synaptic strength at midbrain and striatal sites, and to raise outstanding questions on this topic. This article is part of the Special Issue entitled "A New Dawn in Cannabinoid Neurobiology".
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Kano M, Watanabe T. Type-1 metabotropic glutamate receptor signaling in cerebellar Purkinje cells in health and disease. F1000Res 2017; 6:416. [PMID: 28435670 PMCID: PMC5381626 DOI: 10.12688/f1000research.10485.1] [Citation(s) in RCA: 24] [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] [Accepted: 03/30/2017] [Indexed: 01/28/2023] Open
Abstract
The cerebellum is a brain structure involved in coordination, control, and learning of movements, as well as certain aspects of cognitive function. Purkinje cells are the sole output neurons from the cerebellar cortex and therefore play crucial roles in the overall function of the cerebellum. The type-1 metabotropic glutamate receptor (mGluR1) is a key “hub” molecule that is critically involved in the regulation of synaptic wiring, excitability, synaptic response, and synaptic plasticity of Purkinje cells. In this review, we aim to highlight how mGluR1 controls these events in Purkinje cells. We also describe emerging evidence that altered mGluR1 signaling in Purkinje cells underlies cerebellar dysfunctions in several clinically relevant mouse models of human ataxias.
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Affiliation(s)
- Masanobu Kano
- Department of Neurophysiology, Graduate School of Medicine, The University of Tokyo, Bunkyo-ku, Tokyo, Japan
| | - Takaki Watanabe
- Department of Neurophysiology, Graduate School of Medicine, The University of Tokyo, Bunkyo-ku, Tokyo, Japan
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Information persistence evaluated with low-density dot patterns. Acta Psychol (Amst) 2016; 170:215-25. [PMID: 27614198 DOI: 10.1016/j.actpsy.2016.08.005] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2015] [Revised: 08/04/2016] [Accepted: 08/09/2016] [Indexed: 01/04/2023] Open
Abstract
After more than a century of study, we do not yet fully understand how shapes and patterns are encoded and identified. Greater progress might result from quantifying stimulus information, thus allowing manipulation of the degree to which a shape or pattern can elicit recognition. The present work used discrete dot patterns that are seen as letters of the alphabet. By adjusting the density of the dots in each pattern, one can determine the probability that it will be recognized. The experiments displayed low-density dot patterns to human respondents, assessing the interval across which non-redundant information provided by two compatible subsets would combine to elicit recognition. This provided a measure of the time required for decay of information persistence. Viewed in the context of prior work, the evidence indicates that the retina mediates initial visibility of the stimulus trace, but the longer-duration persistence required for memory retrieval is mediated by visual cortex.
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Power EM, English NA, Empson RM. Are Type 1 metabotropic glutamate receptors a viable therapeutic target for the treatment of cerebellar ataxia? J Physiol 2016; 594:4643-52. [PMID: 26748626 DOI: 10.1113/jp271153] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2015] [Accepted: 12/19/2015] [Indexed: 12/13/2022] Open
Abstract
The cerebellum is a key brain structure for accurate coordination of sensory and motor function. Compared with other brain regions, the cerebellum expresses a particularly high level of Type 1 metabotropic glutamate receptors (mGluR1). In this review we aim to explore the significance of these receptors for cerebellar synapse function and their potential for treating cerebellar ataxia, a poorly treated degenerative motor disorder that is often hereditary. We find a significant and historical literature showing pivotal mechanisms linking mGluR1 activity with healthy cerebellar synaptic function and motor coordination. This is best illustrated by the impaired motor behaviour in mGluR1 knockout mice that bears strong resemblance to human ataxias. More recent literature also indicates that an imbalance of mGluR1 signalling is as critical as its removal. Too much, as well as too little, mGluR1 activity contributes to ataxia in several clinically relevant mouse models, and perhaps also in humans. Given the availability and ongoing refinement of selective pharmacological tools to either reduce (negative allosteric modulation) or boost (positive allosteric modulation) mGluR1 activity, our findings suggest that pharmacological manipulation of these receptors should be explored as an exciting new approach for the treatment of a variety of human cerebellar ataxias.
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Affiliation(s)
- Emmet M Power
- Department of Physiology, Brain Research New Zealand, Brain Health Research Centre, Otago School of Medical Sciences, University of Otago, Dunedin, New Zealand, 9054
| | - Natalya A English
- Department of Physiology, Brain Research New Zealand, Brain Health Research Centre, Otago School of Medical Sciences, University of Otago, Dunedin, New Zealand, 9054
| | - Ruth M Empson
- Department of Physiology, Brain Research New Zealand, Brain Health Research Centre, Otago School of Medical Sciences, University of Otago, Dunedin, New Zealand, 9054
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Lowin T, Straub RH. Cannabinoid-based drugs targeting CB1 and TRPV1, the sympathetic nervous system, and arthritis. Arthritis Res Ther 2015; 17:226. [PMID: 26343051 PMCID: PMC4561168 DOI: 10.1186/s13075-015-0743-x] [Citation(s) in RCA: 59] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
Chronic inflammation in rheumatoid arthritis (RA) is accompanied by activation of the sympathetic nervous system, which can support the immune system to perpetuate inflammation. Several animal models of arthritis already demonstrated a profound influence of adrenergic signaling on the course of RA. Peripheral norepinephrine release from sympathetic terminals is controlled by cannabinoid receptor type 1 (CB1), which is activated by two major endocannabinoids (ECs), arachidonylethanolamine (anandamide) and 2-arachidonylglycerol. These ECs also modulate function of transient receptor potential channels (TRPs) located on sensory nerve fibers, which are abundant in arthritic synovial tissue. TRPs not only induce the sensation of pain but also support inflammation via secretion of pro-inflammatory neuropeptides. In addition, many cell types in synovial tissue express CB1 and TRPs. In this review, we focus on CB1 and transient receptor potential vanilloid 1 (TRPV1)-mediated effects on RA since most anti-inflammatory mechanisms induced by cannabinoids are attributed to cannabinoid receptor type 2 (CB2) activation. We demonstrate how CB1 agonism or antagonism can modulate arthritic disease. The concept of functional antagonism with continuous CB1 activation is discussed. Since fatty acid amide hydrolase (FAAH) is a major EC-degrading enzyme, the therapeutic possibility of FAAH inhibition is studied. Finally, the therapeutic potential of ECs is examined since they interact with cannabinoid receptors and TRPs but do not produce central side effects.
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Affiliation(s)
- Torsten Lowin
- Laboratory of Experimental Rheumatology and Neuroendocrine Immunology, University Hospital of Regensburg, D-93053, Regensburg, Germany.
| | - Rainer H Straub
- Laboratory of Experimental Rheumatology and Neuroendocrine Immunology, University Hospital of Regensburg, D-93053, Regensburg, Germany
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Kishimoto Y, Cagniard B, Yamazaki M, Nakayama J, Sakimura K, Kirino Y, Kano M. Task-specific enhancement of hippocampus-dependent learning in mice deficient in monoacylglycerol lipase, the major hydrolyzing enzyme of the endocannabinoid 2-arachidonoylglycerol. Front Behav Neurosci 2015; 9:134. [PMID: 26082696 PMCID: PMC4451424 DOI: 10.3389/fnbeh.2015.00134] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2015] [Accepted: 05/11/2015] [Indexed: 12/03/2022] Open
Abstract
Growing evidence indicates that the endocannabinoid system is important for the acquisition and/or extinction of learning and memory. However, it is unclear which endocannabinoid(s) play(s) a crucial role in these cognitive functions, especially memory extinction. To elucidate the physiological role of 2-arachidonoylglycerol (2-AG), a major endocannabinoid, in behavioral and cognitive functions, we conducted a comprehensive behavioral test battery in knockout (KO) mice deficient in monoacylglycerol lipase (MGL), the major hydrolyzing enzyme of 2-AG. We found age-dependent increases in spontaneous physical activity (SPA) in MGL KO mice. Next, we tested the MGL KO mice using 5 hippocampus-dependent learning paradigms (i.e., Morris water maze (MWM), contextual fear conditioning, novel object recognition test, trace eyeblink conditioning, and water-finding test). In the MWM, MGL KO mice showed normal acquisition of reference memory, but exhibited significantly faster extinction of the learned behavior. Moreover, they showed faster memory acquisition on the reversal-learning task of the MWM. In contrast, in the contextual fear conditioning, MGL KO mice tended to show slower memory extinction. In the novel object recognition and water-finding tests, MGL KO mice exhibited enhanced memory acquisition. Trace eyeblink conditioning was not altered in MGL KO mice throughout the acquisition and extinction phases. These results indicate that 2-AG signaling is important for hippocampus-dependent learning and memory, but its contribution is highly task-dependent.
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Affiliation(s)
- Yasushi Kishimoto
- Laboratory of Neurobiophysics, Kagawa School of Pharmaceutical Sciences, Tokushima Bunri University Sanuki, Kagawa, Japan
| | - Barbara Cagniard
- Department of Neurophysiology, Graduate School of Medicine, The University of Tokyo Bunkyo-ku, Tokyo, Japan
| | - Maya Yamazaki
- Department of Cellular Neurobiology, Brain Research Institute, Niigata University Niigata, Japan
| | - Junko Nakayama
- Laboratory of Neurobiophysics, Kagawa School of Pharmaceutical Sciences, Tokushima Bunri University Sanuki, Kagawa, Japan
| | - Kenji Sakimura
- Department of Cellular Neurobiology, Brain Research Institute, Niigata University Niigata, Japan
| | - Yutaka Kirino
- Laboratory of Neurobiophysics, Kagawa School of Pharmaceutical Sciences, Tokushima Bunri University Sanuki, Kagawa, Japan
| | - Masanobu Kano
- Department of Neurophysiology, Graduate School of Medicine, The University of Tokyo Bunkyo-ku, Tokyo, Japan
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Abstract
The physiological and pathophysiological functions of the endocannabinoid system have been studied extensively using transgenic and targeted knockout mouse models. The first gene deletions of the cannabinoid CB(1) receptor were described in the late 1990s, soon followed by CB(2) and FAAH mutations in early 2000. These mouse models helped to elucidate the fundamental role of endocannabinoids as retrograde transmitters in the CNS and in the discovery of many unexpected endocannabinoid functions, for example, in the skin, bone and liver. We now have knockout mouse models for almost every receptor and enzyme of the endocannabinoid system. Conditional mutant mice were mostly developed for the CB(1) receptor, which is widely expressed on many different neurons, astrocytes and microglia, as well as on many cells outside the CNS. These mouse strains include "floxed" CB(1) alleles and mice with a conditional re-expression of CB(1). The availability of these mice made it possible to decipher the function of CB(1) in specific neuronal circuits and cell populations or to discriminate between central and peripheral effects. Many of the genetic mouse models were also used in combination with viral expression systems. The purpose of this review is to provide a comprehensive overview of the existing genetic models and to summarize some of the most important discoveries that were made with these animals.
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MESH Headings
- Amidohydrolases/genetics
- Amidohydrolases/metabolism
- Animals
- Endocannabinoids/genetics
- Endocannabinoids/metabolism
- Gene Deletion
- Gene Expression Regulation
- Genotype
- Humans
- Hydrolysis
- Mice, Knockout
- Mice, Mutant Strains
- Monoacylglycerol Lipases/genetics
- Monoacylglycerol Lipases/metabolism
- Mutation
- Phenotype
- Receptor, Cannabinoid, CB1/genetics
- Receptor, Cannabinoid, CB1/metabolism
- Receptor, Cannabinoid, CB2/genetics
- Receptor, Cannabinoid, CB2/metabolism
- Signal Transduction/genetics
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Affiliation(s)
- Andreas Zimmer
- Institute of Molecular Psychiatry, University of Bonn, Bonn, Germany.
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Marcaggi P. Cerebellar Endocannabinoids: Retrograde Signaling from Purkinje Cells. THE CEREBELLUM 2014; 14:341-53. [DOI: 10.1007/s12311-014-0629-5] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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Smaga I, Bystrowska B, Gawliński D, Pomierny B, Stankowicz P, Filip M. Antidepressants and changes in concentration of endocannabinoids and N-acylethanolamines in rat brain structures. Neurotox Res 2014; 26:190-206. [PMID: 24652522 PMCID: PMC4067538 DOI: 10.1007/s12640-014-9465-0] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2013] [Revised: 02/26/2014] [Accepted: 03/06/2014] [Indexed: 12/26/2022]
Abstract
The endocannabinoid (eCB) system has recently been implicated in both the pathogenesis of depression and the action of antidepressants. Here, we investigated the effect of acutely or chronically administering antidepressants [imipramine (IMI) (15 mg/kg), escitalopram (ESC) (10 mg/kg), and tianeptine (10 mg/kg)] on the levels of both eCBs [anandamide (AEA) and 2-arachidonoylglycerol (2-AG)] and N-acylethanolamines (NAEs) [palmitoylethanolamide (PEA) and oleoylethanolamide (OEA)] in various rat brain regions. We also examined the ability of the acute and chronic administration of N-acetylcysteine (NAC) (a mucolytic drug; 100 mg/kg) or URB597 (a fatty acid amide hydrolase inhibitor; 0.3 mg/kg), which have both elicited antidepressant activity in preclinical studies, to affect eCB and NAE levels. Next, we determined whether the observed effects are stable 10 days after the chronic administration of these drugs was halted. We report that the chronic administration of all investigated drugs increased AEA levels in the hippocampus and also increased both AEA and 2-AG levels in the dorsal striatum. NAE levels in limbic regions also increased after treatment with IMI (PEA/OEA), ESC (PEA), and NAC (PEA/OEA). Removing chronic ESC treatment for 10 days affected eCB and NAE levels in the frontal cortex, hippocampus, dorsal striatum, and cerebellum, while a similar tianeptine-free period enhanced accumbal NAE levels. All other drugs maintained their effects after the 10-day washout period. Therefore, the eCB system appears to play a significant role in the mechanism of action of clinically effective and potential antidepressants and may serve as a target for drug design and discovery.
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Affiliation(s)
- Irena Smaga
- Department of Toxicology, Faculty of Pharmacy, College of Medicum, Jagiellonian University, 9, Medyczna Street, 30-688, Kraków, Poland,
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Nadim F, Bucher D. Neuromodulation of neurons and synapses. Curr Opin Neurobiol 2014; 29:48-56. [PMID: 24907657 DOI: 10.1016/j.conb.2014.05.003] [Citation(s) in RCA: 175] [Impact Index Per Article: 17.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2014] [Revised: 05/09/2014] [Accepted: 05/09/2014] [Indexed: 12/15/2022]
Abstract
Neuromodulation underlies the flexibility of neural circuit operation and behavior. Individual neuromodulators can have divergent actions in a neuron by targeting multiple physiological mechanisms. Conversely, multiple neuromodulators may have convergent actions through overlapping targets. The divergent and convergent neuromodulator actions can be unambiguously synergistic or antagonistic, but neuromodulation often entails balanced adjustment of nonlinear membrane and synaptic properties by targeting ion channel and synaptic dynamics rather than just excitability or synaptic strength. In addition, neuromodulators can exert effects at multiple timescales, from short-term adjustments of neuron and synapse function to persistent long-term regulation. This short review summarizes some highlights of the diverse actions of neuromodulators on ion channel and synaptic properties.
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Affiliation(s)
- Farzan Nadim
- Federated Department of Biological Sciences, New Jersey Institute of Technology and Rutgers University, 323 Martin Luther King Blvd, Newark, NJ 07102, United States.
| | - Dirk Bucher
- Federated Department of Biological Sciences, New Jersey Institute of Technology and Rutgers University, 323 Martin Luther King Blvd, Newark, NJ 07102, United States
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Uzunova G, Hollander E, Shepherd J. The role of ionotropic glutamate receptors in childhood neurodevelopmental disorders: autism spectrum disorders and fragile x syndrome. Curr Neuropharmacol 2014; 12:71-98. [PMID: 24533017 PMCID: PMC3915351 DOI: 10.2174/1570159x113116660046] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2013] [Revised: 08/20/2013] [Accepted: 09/25/2013] [Indexed: 12/20/2022] Open
Abstract
Autism spectrum disorder (ASD) and Fragile X syndrome (FXS) are relatively common childhood neurodevelopmental disorders with increasing incidence in recent years. They are currently accepted as disorders of the synapse with alterations in different forms of synaptic communication and neuronal network connectivity. The major excitatory neurotransmitter system in brain, the glutamatergic system, is implicated in learning and memory, synaptic plasticity, neuronal development. While much attention is attributed to the role of metabotropic glutamate receptors in ASD and FXS, studies indicate that the ionotropic glutamate receptors (iGluRs) and their regulatory proteins are also altered in several brain regions. Role of iGluRs in the neurobiology of ASD and FXS is supported by a weight of evidence that ranges from human genetics to in vitro cultured neurons. In this review we will discuss clinical, molecular, cellular and functional changes in NMDA, AMPA and kainate receptors and the synaptic proteins that regulate them in the context of ASD and FXS. We will also discuss the significance for the development of translational biomarkers and treatments for the core symptoms of ASD and FXS.
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Affiliation(s)
- Genoveva Uzunova
- Autism and Obsessive Compulsive Spectrum Program, Department of Psychiatry, Montefiore Medical Center, Albert Einstein College of Medicine, 111 East 210th St, Bronx, New York 10467-2490
| | - Eric Hollander
- Autism and Obsessive Compulsive Spectrum Program, Department of Psychiatry, Montefiore Medical Center, Albert Einstein College of Medicine, 111 East 210th St, Bronx, New York 10467-2490
| | - Jason Shepherd
- Department of Neurobiology and Anatomy, University of Utah School of Medicine, 531A Wintrobe, 20N 1900 E, Salt Lake City, Utah 84132
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Cutando L, Busquets-Garcia A, Puighermanal E, Gomis-González M, Delgado-García JM, Gruart A, Maldonado R, Ozaita A. Microglial activation underlies cerebellar deficits produced by repeated cannabis exposure. J Clin Invest 2013; 123:2816-31. [PMID: 23934130 DOI: 10.1172/jci67569] [Citation(s) in RCA: 88] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2012] [Accepted: 03/28/2013] [Indexed: 11/17/2022] Open
Abstract
Chronic cannabis exposure can lead to cerebellar dysfunction in humans, but the neurobiological mechanisms involved remain incompletely understood. Here, we found that in mice, subchronic administration of the psychoactive component of cannabis, delta9-tetrahydrocannabinol (THC), activated cerebellar microglia and increased the expression of neuroinflammatory markers, including IL-1β. This neuroinflammatory phenotype correlated with deficits in cerebellar conditioned learning and fine motor coordination. The neuroinflammatory phenotype was readily detectable in the cerebellum of mice with global loss of the CB1 cannabinoid receptor (CB1R, Cb1(-/-) mice) and in mice lacking CB1R in the cerebellar parallel fibers, suggesting that CB1R downregulation in the cerebellar molecular layer plays a key role in THC-induced cerebellar deficits. Expression of CB2 cannabinoid receptor (CB2R) and Il1b mRNA was increased under neuroinflammatory conditions in activated CD11b-positive microglial cells. Furthermore, administration of the immunosuppressant minocycline or an inhibitor of IL-1β receptor signaling prevented the deficits in cerebellar function in Cb1(-/-) and THC-withdrawn mice. Our results suggest that cerebellar microglial activation plays a crucial role in the cerebellar deficits induced by repeated cannabis exposure.
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Affiliation(s)
- Laura Cutando
- Laboratori de Neurofarmacologia, Facultat de Ciències de Salut i de Vida, Universitat Pompeu Fabra, Barcelona, Spain
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Abstract
Cerebellar long-term depression (LTD) is a form of long-term synaptic plasticity that is triggered by calcium(Ca2+) signals in the postsynaptic Purkinje cell. This Ca2+comes both from IP3-mediated release from intracellular Ca2+ stores, as well as from Ca2+ influx through voltage-gated Ca2+ channels. The Ca2+ signal that triggers LTD occurs locally within dendritic spines and is due to supralinear summation of signals coming from these two Ca2+ sources. The properties of this postsynaptic Ca2+signal can explain several features of LTD, such as its associativity, synapse specificity, and dependence on thetiming of synaptic activity, and can account for the slow kinetics of LTD expression. Thus, from a Ca2+ signaling perspective, LTD is one of the best understood forms of synaptic plasticity.
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40
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Kvarta MD, Harris-Warrick RM, Johnson BR. Neuromodulator-evoked synaptic metaplasticity within a central pattern generator network. J Neurophysiol 2012; 108:2846-56. [PMID: 22933725 PMCID: PMC3545119 DOI: 10.1152/jn.00586.2012] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2012] [Accepted: 08/27/2012] [Indexed: 12/18/2022] Open
Abstract
Synapses show short-term activity-dependent dynamics that alter the strength of neuronal interactions. This synaptic plasticity can be tuned by neuromodulation as a form of metaplasticity. We examined neuromodulator-induced metaplasticity at a graded chemical synapse in a model central pattern generator (CPG), the pyloric network of the spiny lobster stomatogastric ganglion. Dopamine, serotonin, and octopamine each produce a unique motor pattern from the pyloric network, partially through their modulation of synaptic strength in the network. We characterized synaptic depression and its amine modulation at the graded synapse from the pyloric dilator neuron to the lateral pyloric neuron (PD→LP synapse), driving the PD neuron with both long square pulses and trains of realistic waveforms over a range of presynaptic voltages. We found that the three amines can differentially affect the amplitude of graded synaptic transmission independently of the synaptic dynamics. Low concentrations of dopamine had weak and variable effects on the strength of the graded inhibitory postsynaptic potentials (gIPSPs) but reliably accelerated the onset of synaptic depression and recovery from depression independently of gIPSP amplitude. Octopamine enhanced gIPSP amplitude but decreased the amount of synaptic depression; it slowed the onset of depression and accelerated its recovery during square pulse stimulation. Serotonin reduced gIPSP amplitude but increased the amount of synaptic depression and accelerated the onset of depression. These results suggest that amine-induced metaplasticity at graded chemical synapses can alter the parameters of synaptic dynamics in multiple and independent ways.
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Affiliation(s)
- Mark D Kvarta
- Department of Neurobiology and Behavior, S. G. Mudd Hall, Cornell University, Ithaca, New York 14853, USA
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41
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Gregg LC, Jung KM, Spradley JM, Nyilas R, Suplita RL, Zimmer A, Watanabe M, Mackie K, Katona I, Piomelli D, Hohmann AG. Activation of type 5 metabotropic glutamate receptors and diacylglycerol lipase-α initiates 2-arachidonoylglycerol formation and endocannabinoid-mediated analgesia. J Neurosci 2012; 32:9457-68. [PMID: 22787031 PMCID: PMC3652685 DOI: 10.1523/jneurosci.0013-12.2012] [Citation(s) in RCA: 64] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2011] [Revised: 05/11/2012] [Accepted: 05/17/2012] [Indexed: 11/21/2022] Open
Abstract
Acute stress reduces pain sensitivity by engaging an endocannabinoid signaling circuit in the midbrain. The neural mechanisms governing this process and molecular identity of the endocannabinoid substance(s) involved are unknown. We combined behavior, pharmacology, immunohistochemistry, RNA interference, quantitative RT-PCR, enzyme assays, and lipidomic analyses of endocannabinoid content to uncover the role of the endocannabinoid 2-arachidonoyl-sn-glycerol (2-AG) in controlling pain sensitivity in vivo. Here, we show that footshock stress produces antinociception in rats by activating type 5 metabotropic glutamate receptors (mGlu(5)) in the dorsolateral periaqueductal gray (dlPAG) and mobilizing 2-AG. Stimulation of mGlu(5) in the dlPAG with DHPG [(S)-3,5-dihydroxyphenylglycine] triggered 2-AG formation and enhanced stress-dependent antinociception through a mechanism dependent upon both postsynaptic diacylglycerol lipase (DGL) activity, which releases 2-AG, and presynaptic CB(1) cannabinoid receptors. Pharmacological blockade of DGL activity in the dlPAG with RHC80267 [1,6-bis(cyclohexyloximinocarbonylamino)hexane] and (-)-tetrahydrolipstatin (THL), which inhibit activity of DGL-α and DGL-β isoforms, suppressed stress-induced antinociception. Inhibition of DGL activity in the dlPAG with THL selectively decreased accumulation of 2-AG without altering levels of anandamide. The putative 2-AG-synthesizing enzyme DGL-α colocalized with mGlu(5) at postsynaptic sites of the dlPAG, whereas CB(1) was confined to presynaptic terminals, consistent with a role for 2-AG as a retrograde signaling messenger. Finally, virally mediated silencing of DGL-α, but not DGL-β, transcription in the dlPAG mimicked effects of DGL inhibition in suppressing both endocannabinoid-mediated stress antinociception and 2-AG formation. The results indicate that activation of the postsynaptic mGlu(5)-DGL-α cascade triggers retrograde 2-AG signaling in vivo. This pathway is required for endocannabinoid-mediated stress-induced analgesia.
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Affiliation(s)
- Laura C. Gregg
- Neuroscience Program, Biomedical and Health Sciences Institute, and
| | - Kwang-Mook Jung
- Department of Pharmacology, University of California, Irvine, Irvine, California 92697
| | | | - Rita Nyilas
- Institute of Experimental Medicine, Hungarian Academy of Sciences, H-1083 Budapest, Hungary
| | - Richard L. Suplita
- Psychology Department, University of Georgia, Athens, Georgia 30602-3013
| | - Andreas Zimmer
- Insitute of Molecular Psychiatry, University of Bonn, 53105 Bonn, Germany
| | - Masahiko Watanabe
- Department of Anatomy, Hokkaido University School of Medicine, Sapporo 060-8638, Japan
| | - Ken Mackie
- Department of Psychological and Brain Sciences, Indiana University, Bloomington, Indiana 47405-2204, and
| | - István Katona
- Institute of Experimental Medicine, Hungarian Academy of Sciences, H-1083 Budapest, Hungary
| | - Daniele Piomelli
- Department of Pharmacology, University of California, Irvine, Irvine, California 92697
- Unit of Drug Discovery and Development, Italian Institute of Technology, 16163 Genoa, Italy
| | - Andrea G. Hohmann
- Neuroscience Program, Biomedical and Health Sciences Institute, and
- Psychology Department, University of Georgia, Athens, Georgia 30602-3013
- Department of Psychological and Brain Sciences, Indiana University, Bloomington, Indiana 47405-2204, and
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Steinmetz AB, Edwards CR, Vollmer JM, Erickson MA, O’Donnell BF, Hetrick WP, Skosnik PD. Examining the effects of former cannabis use on cerebellum-dependent eyeblink conditioning in humans. Psychopharmacology (Berl) 2012; 221:133-41. [PMID: 22134474 PMCID: PMC3517929 DOI: 10.1007/s00213-011-2556-1] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/09/2011] [Accepted: 10/19/2011] [Indexed: 10/15/2022]
Abstract
RATIONALE Previous work in humans has shown that chronic cannabis users exhibit disruptions in classical eyeblink conditioning (EBC), a form of associative learning that is known to be dependent on the cerebellum. Based upon previous work in animals, it was hypothesized that these learning deficits were related to cannabinoid receptor (CB1R) downregulation. However, it remains unclear whether there is a recovery of cerebellum-dependent learning after the cessation of cannabis use. METHODS Therefore, former cannabis users (n=10), current cannabis users (n=10), and cannabis-naïve controls (n=10), all free of DSM-IV Axis-I or -II disorders, were evaluated. A standard delay EBC procedure was utilized in which paired presentations of a conditioned stimulus (CS; e.g., tone) and a co-terminating unconditioned stimulus (US; e.g., ocular airpuff) were administered, thus eliciting a conditioned eyeblink response (CR). The primary dependent measures were percentage of CRs and CR latency across conditioning blocks. RESULTS Similar to prior studies, current cannabis users exhibited marked impairments in both the acquisition and timing of CRs compared to controls. Although former cannabis users showed intact CR acquisition compared to controls, they exhibited significantly impaired (shorter) CR latencies. In both cannabis groups, UR amplitude did not differ from controls, indicating normal US processing. CONCLUSIONS These data suggest that a recovery of function has occurred for the learning of the CS-US association, while the accurate timing of the CR shows lasting impairments. Taken together, these results suggest that heavy cannabis use can disrupt timing-related synaptic plasticity within the cerebellum, even after the cessation of cannabis use.
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Affiliation(s)
- Adam B. Steinmetz
- Department of Psychology, University of Iowa, Iowa City, IA 52242, USA
| | - Chad R. Edwards
- Department of Psychological and Brain Sciences, Indiana University, 1101 E. 10th St., Bloomington, IN 47405, USA
| | - Jennifer M. Vollmer
- Department of Psychiatry, Yale University School of Medicine, 300 George St., Suite 901, New Haven, CT 06511, USA
| | - Molly A. Erickson
- Department of Psychological and Brain Sciences, Indiana University, 1101 E. 10th St., Bloomington, IN 47405, USA
| | - Brian F. O’Donnell
- Department of Psychological and Brain Sciences, Indiana University, 1101 E. 10th St., Bloomington, IN 47405, USA
| | - William P. Hetrick
- Department of Psychological and Brain Sciences, Indiana University, 1101 E. 10th St., Bloomington, IN 47405, USA
| | - Patrick D. Skosnik
- Department of Psychiatry, Yale University School of Medicine, 300 George St., Suite 901, New Haven, CT 06511, USA. VA Connecticut Healthcare System, Building 1, 950 Campbell Avenue, West Haven, CT 06516, USA
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Younts TJ, Makani S. Neuronal integration and the depolarizing effects of axonal GABA(A) receptors. J Neurophysiol 2011; 106:2105-7. [PMID: 21813744 DOI: 10.1152/jn.00328.2011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Despite their presence throughout the central nervous system, the impact of axonally expressed gamma-amino-butyric acid type-A receptors (GABA(A)Rs) on neuronal signaling is just beginning to be understood. A recently published article (Pugh JR and Jahr CE, J Neurosci 31: 565-574, 2011) tackled this important issue by investigating GABA(A)R-mediated function in axons of cerebellar granule cells. The results of Pugh and Jahr indicate parallel fiber GABA(A)Rs enhance neurotransmitter release probability and boost axonal and somatic excitability.
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Affiliation(s)
- Thomas J Younts
- Dominick P. Purpura Dept. of Neuroscience, Albert Einstein College of Medicine, 1410 Pelham Parkway South, Rose F. Kennedy Bldg., Rm. 703, Bronx, NY 10461, USA.
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Carey MR. Synaptic mechanisms of sensorimotor learning in the cerebellum. Curr Opin Neurobiol 2011; 21:609-15. [PMID: 21767944 DOI: 10.1016/j.conb.2011.06.011] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2011] [Revised: 06/22/2011] [Accepted: 06/23/2011] [Indexed: 01/20/2023]
Abstract
The cerebellum plays an essential role in motor learning. The ability to identify specific sensory and motor signals carried by neurons with known connectivity makes the cerebellum an attractive system for investigating how synaptic plasticity relates to learning. Early studies focused primarily on a single form of plasticity, long-term depression at parallel fiber-Purkinje cell synapses. Recent work has highlighted both the diversity of synaptic plasticity that exists within the cerebellum and the fact that individual plasticity mechanisms can have unexpected consequences when they act within neural circuits.
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Affiliation(s)
- Megan R Carey
- Neural Circuits and Behavior Laboratory, Champalimaud Neuroscience Programme, Champalimaud Centre for the Unknown, Av. Brasília, Doca de Pedrouços, 1400-038 Lisboa, Portugal.
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