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Cho H, Huh KM, Shim MS, Cho YY, Lee JY, Lee HS, Kwon YJ, Kang HC. Selective delivery of imaging probes and therapeutics to the endoplasmic reticulum or Golgi apparatus: Current strategies and beyond. Adv Drug Deliv Rev 2024; 212:115386. [PMID: 38971180 DOI: 10.1016/j.addr.2024.115386] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2024] [Revised: 06/14/2024] [Accepted: 07/01/2024] [Indexed: 07/08/2024]
Abstract
To maximize therapeutic effects and minimize unwanted effects, the interest in drug targeting to the endoplasmic reticulum (ER) or Golgi apparatus (GA) has been recently growing because two organelles are distributing hubs of cellular building/signaling components (e.g., proteins, lipids, Ca2+) to other organelles and the plasma membrane. Their structural or functional damages induce organelle stress (i.e., ER or GA stress), and their aggravation is strongly related to diseases (e.g., cancers, liver diseases, brain diseases). Many efforts have been developed to image (patho)physiological functions (e.g., oxidative stress, protein/lipid-related processing) and characteristics (e.g., pH, temperature, biothiols, reactive oxygen species) in the target organelles and to deliver drugs for organelle disruption using organelle-targeting moieties. Therefore, this review will overview the structure, (patho)physiological functions/characteristics, and related diseases of the organelles of interest. Future direction on ER or GA targeting will be discussed by understanding current strategies and investigations on targeting, imaging/sensing, and therapeutic systems.
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Affiliation(s)
- Hana Cho
- Department of Pharmacy, College of Pharmacy, The Catholic University of Korea, Bucheon 14662, Republic of Korea
| | - Kang Moo Huh
- Departments of Polymer Science and Engineering & Materials Science and Engineering, Chungnam National University, Daejeon 34134, Republic of Korea
| | - Min Suk Shim
- Division of Bioengineering, Incheon National University, Incheon 22012, Republic of Korea
| | - Yong-Yeon Cho
- Department of Pharmacy, College of Pharmacy, The Catholic University of Korea, Bucheon 14662, Republic of Korea; Research Institute for Controls and Materials of Regulated Cell Death, The Catholic University of Korea, Bucheon 14662, Republic of Korea
| | - Joo Young Lee
- Department of Pharmacy, College of Pharmacy, The Catholic University of Korea, Bucheon 14662, Republic of Korea; Research Institute for Controls and Materials of Regulated Cell Death, The Catholic University of Korea, Bucheon 14662, Republic of Korea
| | - Hye Suk Lee
- Department of Pharmacy, College of Pharmacy, The Catholic University of Korea, Bucheon 14662, Republic of Korea; Research Institute for Controls and Materials of Regulated Cell Death, The Catholic University of Korea, Bucheon 14662, Republic of Korea
| | - Young Jik Kwon
- Department of Pharmaceutical Sciences, University of California, Irvine, CA 92697, USA
| | - Han Chang Kang
- Department of Pharmacy, College of Pharmacy, The Catholic University of Korea, Bucheon 14662, Republic of Korea; Research Institute for Controls and Materials of Regulated Cell Death, The Catholic University of Korea, Bucheon 14662, Republic of Korea.
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2
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Li Y. Differential behaviors of calcium-induced calcium release in one dimensional dendrite by Nernst-Planck equation, cable model and pure diffusion model. Cogn Neurodyn 2024; 18:1285-1305. [PMID: 38826668 PMCID: PMC11143177 DOI: 10.1007/s11571-023-09952-0] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2022] [Revised: 02/16/2023] [Accepted: 03/08/2023] [Indexed: 06/04/2024] Open
Abstract
The source and dynamics of calcium is the key factor that regulates dendritic integration. Apart from the voltage-gated and ligand-gated calcium influx, an important source of calcium is from inner store of endoplasmic reticulum with a regenerative process of calcium-induced calcium release (CICR). To trigger this process, inositol 1,4,5-trisphosphate (IP3) and calcium are needed to satisfy certain requirements. The aim of our paper is to investigate how the CICR depends on the dynamics of membrane potential. We utilize one dimensional dendritic model to calculate membrane potential by Nernst-Planck Equation (NPE) and cable model and Pure Diffusion (PD) model, computational simulations are carried out to inject the calcium influx by synaptic stimulation and to predict subsequent CICR and calcium wave propagation. Our results demonstrate that CICR initiation and calcium wave propagation have much difference between electro-diffusion process of NPE and cable model. We find that cable model has lower threshold of IP3 stimulation to trigger CICR but is more difficult for calcium propagation than NPE, PD model requires even higher threshold of IP3 to initiate CICR process and calcium duration is shorter than NPE; the regenerative calcium wave propagates with faster speed in NPE than that in cable model and in PD model. Our work addresses the important role of electro-diffusion dynamics of charged ions in regulating CICR process in dendritic structure; and provides theoretical predictions for neurological process which requires sustaining calcium for downstream signaling processes.
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Affiliation(s)
- Yinyun Li
- School of Systems Science, Beijing Normal University, Beijing, 100875 China
- Department of Mathematics and Statistics, Washington State University Vancouver, Vancouver, USA
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3
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Canepari M, Ross WN. Spatial and temporal aspects of neuronal calcium and sodium signals measured with low-affinity fluorescent indicators. Pflugers Arch 2024; 476:39-48. [PMID: 37798555 DOI: 10.1007/s00424-023-02865-1] [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: 08/14/2023] [Revised: 09/12/2023] [Accepted: 09/21/2023] [Indexed: 10/07/2023]
Abstract
Low-affinity fluorescent indicators for Ca2+ or Na+ allow measuring the dynamics of intracellular concentration of these ions with little perturbation from physiological conditions because they are weak buffers. When using synthetic indicators, which are small molecules with fast kinetics, it is also possible to extract spatial and temporal information on the sources of ion transients, their localization, and their disposition. This review examines these important aspects from the biophysical point of view, and how they have been recently exploited in neurophysiological studies. We first analyze the environment where Ca2+ and Na+ indicators are inserted, highlighting the interpretation of the two different signals. Then, we address the information that can be obtained by analyzing the rising phase and the falling phase of the Ca2+ and Na+ transients evoked by different stimuli, focusing on the kinetics of ionic currents and on the spatial interpretation of these measurements, especially on events in axons and dendritic spines. Finally, we suggest how Ca2+ or Na+ imaging using low-affinity synthetic fluorescent indicators can be exploited in future fundamental or applied research.
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Affiliation(s)
- Marco Canepari
- LIPhy, CNRS, Univ. Grenoble Alpes, F-38000, Grenoble, France.
- Laboratories of Excellence, Ion Channel Science and Therapeutics, Valbonne, France.
- Institut National de la Santé et Recherche Médicale, Paris, France.
| | - William N Ross
- Department of Physiology, New York Medical College, Valhalla, NY, 10595, USA
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4
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Girigoswami K, Pallavi P, Girigoswami A. Intricate subcellular journey of nanoparticles to the enigmatic domains of endoplasmic reticulum. Drug Deliv 2023; 30:2284684. [PMID: 37990530 PMCID: PMC10987057 DOI: 10.1080/10717544.2023.2284684] [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: 08/24/2023] [Accepted: 11/05/2023] [Indexed: 11/23/2023] Open
Abstract
It is evident that site-specific systemic drug delivery can reduce side effects, systemic toxicity, and minimal dosage requirements predominantly by delivering drugs to particular pathological sites, cells, and even subcellular structures. The endoplasmic reticulum (ER) and associated cell organelles play a vital role in several essential cellular functions and activities, such as the synthesis of lipids, steroids, membrane-associated proteins along with intracellular transport, signaling of Ca2+, and specific response to stress. Therefore, the dysfunction of ER is correlated with numerous diseases where cancer, neurodegenerative disorders, diabetes mellitus, hepatic disorder, etc., are very common. To achieve satisfactory therapeutic results in certain diseases, it is essential to engineer delivery systems that can effectively enter the cells and target ER. Nanoparticles are highly biocompatible, contain a variety of cargos or payloads, and can be modified in a pliable manner to achieve therapeutic effectiveness at the subcellular level when delivered to specific organelles. Passive targeting drug delivery vehicles, or active targeting drug delivery systems, reduce the nonselective accumulation of drugs while reducing side effects by modifying them with small molecular compounds, antibodies, polypeptides, or isolated bio-membranes. The targeting of ER and closely associated organelles in cells using nanoparticles, however, is still unsymmetrically understood. Therefore, here we summarized the pathophysiological prospect of ER stress, involvement of ER and mitochondrial response, disease related to ER dysfunctions, essential therapeutics, and nanoenabled modulation of their delivery to optimize therapy.
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Affiliation(s)
- Koyeli Girigoswami
- Medical Bionanotechnology, Faculty of Allied Health Sciences, Chettinad Hospital & Research Institute (CHRI), Chettinad Academy of Research and Education (CARE), Kelambakkam, Chennai, TN, India
| | - Pragya Pallavi
- Medical Bionanotechnology, Faculty of Allied Health Sciences, Chettinad Hospital & Research Institute (CHRI), Chettinad Academy of Research and Education (CARE), Kelambakkam, Chennai, TN, India
| | - Agnishwar Girigoswami
- Medical Bionanotechnology, Faculty of Allied Health Sciences, Chettinad Hospital & Research Institute (CHRI), Chettinad Academy of Research and Education (CARE), Kelambakkam, Chennai, TN, India
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5
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Zhou J, Zhang J, Cao L, Liu Y, Liu L, Liu C, Li X. Ginsenoside Rg 1 modulates vesicular dopamine storage and release during exocytosis revealed with single-vesicle electrochemistry. Chem Commun (Camb) 2023; 59:3087-3090. [PMID: 36804575 DOI: 10.1039/d2cc06950d] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/16/2023]
Abstract
Ginsenoside Rg1, a tetracyclic triterpenoid derivative extracted from the roots of Panax ginseng C. A. Meyer, can enhance learning and memory and improve cognitive impairment. However, whether or how it affects vesicular dopamine storage and its release during exocytosis remains unknown. By using single-vesicle electrochemistry, we for the first time find out that Rg1 not only upregulates vesicular dopamine content but also increases exocytosis frequency and modulates dopamine release during exocytosis in PC12 cells, which may relate to the activation of protein kinases, causing a series of biological cascades. This finding offers the possible link between Rg1 and vesicular chemical storage and exocytotic release, which is of significance for understanding the nootropic role of Rg1 from the perspective of neurotransmission.
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Affiliation(s)
- Junlan Zhou
- Key Laboratory of Mass Spectrometry Imaging and Metabolomics (Minzu University of China), National Ethnic Affairs Commission, Beijing 100081, China. .,Center for Imaging and Systems Biology, College of Life and Environmental Sciences, Minzu University of China, Beijing 100081, China
| | - Jing Zhang
- Key Laboratory of Mass Spectrometry Imaging and Metabolomics (Minzu University of China), National Ethnic Affairs Commission, Beijing 100081, China. .,Center for Imaging and Systems Biology, College of Life and Environmental Sciences, Minzu University of China, Beijing 100081, China
| | - Lijiao Cao
- Key Laboratory of Mass Spectrometry Imaging and Metabolomics (Minzu University of China), National Ethnic Affairs Commission, Beijing 100081, China. .,Center for Imaging and Systems Biology, College of Life and Environmental Sciences, Minzu University of China, Beijing 100081, China
| | - Yuying Liu
- Key Laboratory of Mass Spectrometry Imaging and Metabolomics (Minzu University of China), National Ethnic Affairs Commission, Beijing 100081, China. .,Center for Imaging and Systems Biology, College of Life and Environmental Sciences, Minzu University of China, Beijing 100081, China.,State Key Laboratory of Natural and Biomimetic Drugs and Department of Pharmaceutical Analysis, School of Pharmaceutical Sciences, Peking University, Beijing 100191, China
| | - Luyao Liu
- Key Laboratory of Mass Spectrometry Imaging and Metabolomics (Minzu University of China), National Ethnic Affairs Commission, Beijing 100081, China. .,Center for Imaging and Systems Biology, College of Life and Environmental Sciences, Minzu University of China, Beijing 100081, China
| | - Chunlan Liu
- Key Laboratory of Mass Spectrometry Imaging and Metabolomics (Minzu University of China), National Ethnic Affairs Commission, Beijing 100081, China. .,Center for Imaging and Systems Biology, College of Life and Environmental Sciences, Minzu University of China, Beijing 100081, China
| | - Xianchan Li
- Key Laboratory of Mass Spectrometry Imaging and Metabolomics (Minzu University of China), National Ethnic Affairs Commission, Beijing 100081, China. .,Center for Imaging and Systems Biology, College of Life and Environmental Sciences, Minzu University of China, Beijing 100081, China.,State Key Laboratory of Natural and Biomimetic Drugs and Department of Pharmaceutical Analysis, School of Pharmaceutical Sciences, Peking University, Beijing 100191, China
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Adeoye T, Shah SI, Demuro A, Rabson DA, Ullah G. Upregulated Ca 2+ Release from the Endoplasmic Reticulum Leads to Impaired Presynaptic Function in Familial Alzheimer's Disease. Cells 2022; 11:2167. [PMID: 35883609 PMCID: PMC9315668 DOI: 10.3390/cells11142167] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2022] [Revised: 06/28/2022] [Accepted: 07/02/2022] [Indexed: 12/10/2022] Open
Abstract
Neurotransmitter release from presynaptic terminals is primarily regulated by rapid Ca2+ influx through membrane-resident voltage-gated Ca2+ channels (VGCCs). Moreover, accumulating evidence indicates that the endoplasmic reticulum (ER) is extensively present in axonal terminals of neurons and plays a modulatory role in synaptic transmission by regulating Ca2+ levels. Familial Alzheimer's disease (FAD) is marked by enhanced Ca2+ release from the ER and downregulation of Ca2+ buffering proteins. However, the precise consequence of impaired Ca2+ signaling within the vicinity of VGCCs (active zone (AZ)) on exocytosis is poorly understood. Here, we perform in silico experiments of intracellular Ca2+ signaling and exocytosis in a detailed biophysical model of hippocampal synapses to investigate the effect of aberrant Ca2+ signaling on neurotransmitter release in FAD. Our model predicts that enhanced Ca2+ release from the ER increases the probability of neurotransmitter release in FAD. Moreover, over very short timescales (30-60 ms), the model exhibits activity-dependent and enhanced short-term plasticity in FAD, indicating neuronal hyperactivity-a hallmark of the disease. Similar to previous observations in AD animal models, our model reveals that during prolonged stimulation (~450 ms), pathological Ca2+ signaling increases depression and desynchronization with stimulus, causing affected synapses to operate unreliably. Overall, our work provides direct evidence in support of a crucial role played by altered Ca2+ homeostasis mediated by intracellular stores in FAD.
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Affiliation(s)
- Temitope Adeoye
- Department of Physics, University of South Florida, Tampa, FL 33620, USA; (T.A.); (S.I.S.); (D.A.R.)
| | - Syed I. Shah
- Department of Physics, University of South Florida, Tampa, FL 33620, USA; (T.A.); (S.I.S.); (D.A.R.)
| | - Angelo Demuro
- Department of Neurobiology and Behavior, University of California, Irvine, CA 92697, USA;
| | - David A. Rabson
- Department of Physics, University of South Florida, Tampa, FL 33620, USA; (T.A.); (S.I.S.); (D.A.R.)
| | - Ghanim Ullah
- Department of Physics, University of South Florida, Tampa, FL 33620, USA; (T.A.); (S.I.S.); (D.A.R.)
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7
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Intracellular calcium release: A conductor of compartmentalized dendritic plasticity. Cell 2022; 185:1627-1629. [DOI: 10.1016/j.cell.2022.04.027] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2022] [Revised: 04/15/2022] [Accepted: 04/18/2022] [Indexed: 11/22/2022]
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8
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O’Hare JK, Gonzalez KC, Herrlinger SA, Hirabayashi Y, Hewitt VL, Blockus H, Szoboszlay M, Rolotti SV, Geiller TC, Negrean A, Chelur V, Polleux F, Losonczy A. Compartment-specific tuning of dendritic feature selectivity by intracellular Ca 2+ release. Science 2022; 375:eabm1670. [PMID: 35298275 PMCID: PMC9667905 DOI: 10.1126/science.abm1670] [Citation(s) in RCA: 31] [Impact Index Per Article: 15.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Dendritic calcium signaling is central to neural plasticity mechanisms that allow animals to adapt to the environment. Intracellular calcium release (ICR) from the endoplasmic reticulum has long been thought to shape these mechanisms. However, ICR has not been investigated in mammalian neurons in vivo. We combined electroporation of single CA1 pyramidal neurons, simultaneous imaging of dendritic and somatic activity during spatial navigation, optogenetic place field induction, and acute genetic augmentation of ICR cytosolic impact to reveal that ICR supports the establishment of dendritic feature selectivity and shapes integrative properties determining output-level receptive fields. This role for ICR was more prominent in apical than in basal dendrites. Thus, ICR cooperates with circuit-level architecture in vivo to promote the emergence of behaviorally relevant plasticity in a compartment-specific manner.
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Affiliation(s)
- Justin K. O’Hare
- Department of Neuroscience, Columbia University; New York, NY, 10027, United States
- Mortimer B. Zuckerman Mind Brain Behavior Institute, Columbia University; New York, NY, 10027, United States
| | - Kevin C. Gonzalez
- Department of Neuroscience, Columbia University; New York, NY, 10027, United States
- Mortimer B. Zuckerman Mind Brain Behavior Institute, Columbia University; New York, NY, 10027, United States
| | - Stephanie A. Herrlinger
- Department of Neuroscience, Columbia University; New York, NY, 10027, United States
- Mortimer B. Zuckerman Mind Brain Behavior Institute, Columbia University; New York, NY, 10027, United States
| | - Yusuke Hirabayashi
- Department of Chemistry and Biotechnology, School of Engineering, The University of Tokyo; Tokyo, Japan
| | - Victoria L. Hewitt
- Department of Neuroscience, Columbia University; New York, NY, 10027, United States
- Mortimer B. Zuckerman Mind Brain Behavior Institute, Columbia University; New York, NY, 10027, United States
| | - Heike Blockus
- Department of Neuroscience, Columbia University; New York, NY, 10027, United States
- Mortimer B. Zuckerman Mind Brain Behavior Institute, Columbia University; New York, NY, 10027, United States
| | - Miklos Szoboszlay
- Department of Neuroscience, Columbia University; New York, NY, 10027, United States
- Mortimer B. Zuckerman Mind Brain Behavior Institute, Columbia University; New York, NY, 10027, United States
| | - Sebi V. Rolotti
- Department of Neuroscience, Columbia University; New York, NY, 10027, United States
- Mortimer B. Zuckerman Mind Brain Behavior Institute, Columbia University; New York, NY, 10027, United States
| | - Tristan C. Geiller
- Department of Neuroscience, Columbia University; New York, NY, 10027, United States
- Mortimer B. Zuckerman Mind Brain Behavior Institute, Columbia University; New York, NY, 10027, United States
| | - Adrian Negrean
- Department of Neuroscience, Columbia University; New York, NY, 10027, United States
- Mortimer B. Zuckerman Mind Brain Behavior Institute, Columbia University; New York, NY, 10027, United States
| | - Vikas Chelur
- Department of Neuroscience, Columbia University; New York, NY, 10027, United States
| | - Franck Polleux
- Department of Neuroscience, Columbia University; New York, NY, 10027, United States
- Mortimer B. Zuckerman Mind Brain Behavior Institute, Columbia University; New York, NY, 10027, United States
- Kavli Institute for Brain Science, Columbia University; New York, NY, 10027, United States
| | - Attila Losonczy
- Department of Neuroscience, Columbia University; New York, NY, 10027, United States
- Mortimer B. Zuckerman Mind Brain Behavior Institute, Columbia University; New York, NY, 10027, United States
- Kavli Institute for Brain Science, Columbia University; New York, NY, 10027, United States
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9
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Ca 2+ channel blockade reduces cocaine's vasoconstriction and neurotoxicity in the prefrontal cortex. Transl Psychiatry 2021; 11:459. [PMID: 34489397 PMCID: PMC8421405 DOI: 10.1038/s41398-021-01573-7] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/01/2020] [Revised: 07/23/2021] [Accepted: 08/17/2021] [Indexed: 02/08/2023] Open
Abstract
Cocaine profoundly affects both cerebral blood vessels and neuronal activity in the brain. The vasoconstrictive effects of cocaine, concurrently with its effects on neuronal [Ca2+]i accumulation are likely to jeopardize neuronal tissue that in the prefrontal cortex (PFC) could contribute to impaired self-regulation and compulsive cocaine consumption. Here we used optical imaging to study the cerebrovascular and neuronal effects of acute cocaine (1 mg/kg i.v.) and to examine whether selective blockade of L-type Ca2+ channels by Nifedipine (NIF) (0.5 mg/kg i.v.) would alleviate cocaine's effects on hemodynamics (measured with cerebral blood volume, HbT), oxygenation (measured with oxygenated hemoglobin, HbO2) and neuronal [Ca2+]i, which were concomitantly measured in the PFC of naive rats. Our results show that in the PFC acute cocaine significantly reduced flow delivery (HbT), increased neuronal [Ca2+]i accumulation and profoundly reduced tissue oxygenation (HbO2) and these effects were significantly attenuated by NIF pretreatment. They also show that cocaine-induced vasoconstriction is distinct from its increase of neuronal [Ca2+]i accumulation though both of them contribute to hypoxemia and both effects were attenuated by NIF. These results provide evidence that blockade of voltage-gated L-type Ca2+ channels might be beneficial in preventing vasoconstriction and neurotoxic effects of cocaine and give support for further clinical investigations to determine their value in reducing cocaine's neurotoxicity in cocaine use disorders.
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Nakamura-Maruyama E, Kai R, Himi N, Okabe N, Narita K, Miyazaki T, Aoki S, Miyamoto O. Ryanodine receptors are involved in the improvement of depression-like behaviors through electroconvulsive shock in stressed mice. Brain Stimul 2020; 14:36-47. [PMID: 33166727 DOI: 10.1016/j.brs.2020.11.001] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2020] [Revised: 10/20/2020] [Accepted: 11/01/2020] [Indexed: 11/18/2022] Open
Abstract
BACKGROUND Electroconvulsive therapy (ECT) is effective for treating depression. However, the mechanisms underlying the antidepressant effects of ECT remain unknown. Depressed patients exhibit abnormal Ca2+ kinetics. Early stages of the intracellular Ca2+ signaling pathway involve the release of Ca2+ from the endoplasmic reticulum (ER) via Ca2+ release channels. OBJECTIVE We considered that depression may be improved via ECT-induced normalization of intracellular Ca2+ regulation through the Ca2+ release channels. The current study aimed to investigate the effects of ECT on two Ca2+ release channels, ryanodine receptors (RyRs) and inositol 1,4,5-trisphosphate receptors (IP3Rs). METHODS A mouse depression-like model subjected to water immersion with restraint stress was administered electroconvulsive shock (ECS) therapy. Their depression-like status was behaviorally and histologically assessed using forced swimming tests, novelty-suppressed feeding tests, and by evaluating neurogenesis in the hippocampal dentate gyrus, respectively. A RyRs blocker, dantrolene, was administered prior to ECS, and the changes in depression-like conditions were examined. RESULTS The protein expressions of RyR1 and RyR3 significantly increased in the hippocampus of the mouse model with depression-like symptoms. This increase was attenuated as depression-like symptoms were reduced due to ECS application. However, pre-injection with dantrolene reduced the antidepressant effects of ECS. CONCLUSIONS A significant increase in RyRs expression in a depression-like state and exacerbation of depression-like symptoms by RyRs inhibitors may be caused by RyRs dysfunction, suggesting overexpression of RyRs is a compensatory effect. Normalization of RyRs expression levels by ECS suggests that ECT normalizes the Ca2+ release via RyRs. Thus, normalizing the function of RyRs may play an important role in the therapeutic effect of ECT.
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Affiliation(s)
| | - Risa Kai
- Department of Physiology 2, Kawasaki Medical School, Kurashiki, Japan
| | - Naoyuki Himi
- Department of Physiology 2, Kawasaki Medical School, Kurashiki, Japan
| | - Naohiko Okabe
- Department of Physiology 2, Kawasaki Medical School, Kurashiki, Japan
| | - Kazuhiko Narita
- Department of Physiology 2, Kawasaki Medical School, Kurashiki, Japan
| | - Tetsuji Miyazaki
- Department of Psychiatry, Kawasaki Medical School, Kurashiki, Japan
| | - Shozo Aoki
- Department of Psychiatry, Kawasaki Medical School, Kurashiki, Japan
| | - Osamu Miyamoto
- Department of Physiology 2, Kawasaki Medical School, Kurashiki, Japan.
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11
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Choi IS, Cho JH, Nakamura M, Jang IS. Menthol facilitates excitatory and inhibitory synaptic transmission in rat medullary dorsal horn neurons. Brain Res 2020; 1750:147149. [PMID: 33035497 DOI: 10.1016/j.brainres.2020.147149] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2020] [Revised: 09/14/2020] [Accepted: 10/02/2020] [Indexed: 10/23/2022]
Abstract
Menthol, which acts as an agonist for transient receptor potential melastatin 8 (TRPM8), has complex effects on nociceptive transmission, including pain relief and hyperalgesia. Here, we addressed the effects of menthol on spontaneous excitatory and inhibitory postsynaptic currents (sEPSCs and sIPSCs, respectively) in medullary dorsal horn neurons, using a whole-cell patch-clamp technique. Menthol significantly increased sEPSC frequency, in a concentration-dependent manner, without affecting current amplitudes. The menthol-induced increase in sEPSC frequency could be completely blocked by AMTB, a TRPM8 antagonist, but was not blocked by HC-030031, a transient receptor potential ankyrin 1 (TRPA1) antagonist. Menthol still increased sEPSC frequency in the presence of Cd2+, a general voltage-gated Ca2+ channel blocker, suggesting that voltage-gated Ca2+ channels are not involved in the menthol-induced increase in sEPSC frequency. However, menthol failed to increase sEPSC frequency in the absence of extracellular Ca2+, suggesting that TRPM8 on primary afferent terminals is Ca2+ permeable. On the other hand, menthol also increased sIPSC frequency, without affecting current amplitudes. The menthol-induced increase in sIPSC frequency could be completely blocked by either AMTB or CNQX, an AMPA/KA receptor antagonist, suggesting that the indirect increase in excitability of inhibitory interneurons may lead to the facilitation of spontaneous GABA and/or glycine release. The present results suggested that menthol exerts analgesic effects, via the enhancement of inhibitory synaptic transmission, through central feed-forward neural circuits within the medullary dorsal horn region.
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Affiliation(s)
- In-Sun Choi
- Department of Pharmacology, School of Dentistry, Kyungpook National University, Daegu 41940, Republic of Korea
| | - Jin-Hwa Cho
- Department of Pharmacology, School of Dentistry, Kyungpook National University, Daegu 41940, Republic of Korea
| | - Michiko Nakamura
- Department of Pharmacology, School of Dentistry, Kyungpook National University, Daegu 41940, Republic of Korea; Brain Science & Engineering Institute, Kyungpook National University, Daegu 41940, Republic of Korea
| | - Il-Sung Jang
- Department of Pharmacology, School of Dentistry, Kyungpook National University, Daegu 41940, Republic of Korea; Brain Science & Engineering Institute, Kyungpook National University, Daegu 41940, Republic of Korea.
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12
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Oleuropein promotes hippocampal LTP via intracellular calcium mobilization and Ca2+-permeable AMPA receptor surface recruitment. Neuropharmacology 2020; 176:108196. [DOI: 10.1016/j.neuropharm.2020.108196] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2019] [Revised: 05/26/2020] [Accepted: 06/08/2020] [Indexed: 12/27/2022]
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13
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Calsequestrin Deletion Facilitates Hippocampal Synaptic Plasticity and Spatial Learning in Post-Natal Development. Int J Mol Sci 2020; 21:ijms21155473. [PMID: 32751833 PMCID: PMC7432722 DOI: 10.3390/ijms21155473] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2020] [Revised: 07/15/2020] [Accepted: 07/30/2020] [Indexed: 11/17/2022] Open
Abstract
Experimental evidence highlights the involvement of the endoplasmic reticulum (ER)-mediated Ca2+ signals in modulating synaptic plasticity and spatial memory formation in the hippocampus. Ca2+ release from the ER mainly occurs through two classes of Ca2+ channels, inositol 1,4,5-trisphosphate receptors (InsP3Rs) and ryanodine receptors (RyRs). Calsequestrin (CASQ) and calreticulin (CR) are the most abundant Ca2+-binding proteins allowing ER Ca2+ storage. The hippocampus is one of the brain regions expressing CASQ, but its role in neuronal activity, plasticity, and the learning processes is poorly investigated. Here, we used knockout mice lacking both CASQ type-1 and type-2 isoforms (double (d)CASQ-null mice) to: a) evaluate in adulthood the neuronal electrophysiological properties and synaptic plasticity in the hippocampal Cornu Ammonis 1 (CA1) field and b) study the performance of knockout mice in spatial learning tasks. The ablation of CASQ increased the CA1 neuron excitability and improved the long-term potentiation (LTP) maintenance. Consistently, (d)CASQ-null mice performed significantly better than controls in the Morris Water Maze task, needing a shorter time to develop a spatial preference for the goal. The Ca2+ handling analysis in CA1 pyramidal cells showed a decrement of Ca2+ transient amplitude in (d)CASQ-null mouse neurons, which is consistent with a decrease in afterhyperpolarization improving LTP. Altogether, our findings suggest that CASQ deletion affects activity-dependent ER Ca2+ release, thus facilitating synaptic plasticity and spatial learning in post-natal development.
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Calcium-induced calcium release and type 3 ryanodine receptors modulate the slow afterhyperpolarising current, sIAHP, and its potentiation in hippocampal pyramidal neurons. PLoS One 2020; 15:e0230465. [PMID: 32559219 PMCID: PMC7304577 DOI: 10.1371/journal.pone.0230465] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2020] [Accepted: 06/03/2020] [Indexed: 12/21/2022] Open
Abstract
The slow afterhyperpolarising current, sIAHP, is a Ca2+-dependent current that plays an important role in the late phase of spike frequency adaptation. sIAHP is activated by voltage-gated Ca2+ channels, while the contribution of calcium from ryanodine-sensitive intracellular stores, released by calcium-induced calcium release (CICR), is controversial in hippocampal pyramidal neurons. Three types of ryanodine receptors (RyR1-3) are expressed in the hippocampus, with RyR3 showing a predominant expression in CA1 neurons. We investigated the specific role of CICR, and particularly of its RyR3-mediated component, in the regulation of the sIAHP amplitude and time course, and the activity-dependent potentiation of the sIAHP in rat and mouse CA1 pyramidal neurons. Here we report that enhancement of CICR by caffeine led to an increase in sIAHP amplitude, while inhibition of CICR by ryanodine caused a small, but significant reduction of sIAHP. Inhibition of ryanodine-sensitive Ca2+ stores by ryanodine or depletion by the SERCA pump inhibitor cyclopiazonic acid caused a substantial attenuation in the sIAHP activity-dependent potentiation in both rat and mouse CA1 pyramidal neurons. Neurons from mice lacking RyR3 receptors exhibited a sIAHP with features undistinguishable from wild-type neurons, which was similarly reduced by ryanodine. However, the lack of RyR3 receptors led to a faster and reduced activity-dependent potentiation of sIAHP. We conclude that ryanodine receptor-mediated CICR contributes both to the amplitude of the sIAHP at steady state and its activity-dependent potentiation in rat and mouse hippocampal pyramidal neurons. In particular, we show that RyR3 receptors play an essential and specific role in shaping the activity-dependent potentiation of the sIAHP. The modulation of activity-dependent potentiation of sIAHP by RyR3-mediated CICR contributes to plasticity of intrinsic neuronal excitability and is likely to play a critical role in higher cognitive functions, such as learning and memory.
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Jang IS, Nakamura M, Kubota H, Noda M, Akaike N. Extracellular pH modulation of excitatory synaptic transmission in hippocampal CA3 neurons. J Neurophysiol 2020; 123:2426-2436. [PMID: 32401126 DOI: 10.1152/jn.00013.2020] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
In this study, the effect of extracellular pH on glutamatergic synaptic transmission was examined in mechanically dissociated rat hippocampal CA3 pyramidal neurons using a whole-cell patch-clamp technique under voltage-clamp conditions. Native synaptic boutons were isolated without using any enzymes, using a so-called "synapse bouton preparation," and preserved for the electrical stimulation of single boutons. Both the frequency and amplitude of spontaneous excitatory postsynaptic currents (sEPSCs) were found to decrease and increase in response to modest acidic (~pH 6.5) and basic (~pH 8.5) solutions, respectively. These changes in sEPSC frequency were not affected by the addition of TTX but completely disappeared by successive addition of Cd2+. However, changes in sEPSC amplitude induced by acidic and basic extracellular solutions were not affected by the addition of neither TTX nor Cd2+. The glutamate-induced whole-cell currents were decreased and increased by acidic and basic solutions, respectively. Acidic pH also decreased the amplitude and increased the failure rate (Rf) and paired-pulse rate (PPR) of glutamatergic electrically evoked excitatory postsynaptic currents (eEPSCs), while a basic pH increased the amplitude and decreased both the Rf and PPR of eEPSCs. The kinetics of the currents were not affected by changes in pH. Acidic and basic solutions decreased and increased voltage-gated Ca2+ but not Na+ channel currents in the dentate gyrus granule cell bodies. Our results indicate that extracellular pH modulates excitatory transmission via both pre- and postsynaptic sites, with the presynaptic modulation correlated to changes in voltage-gated Ca2+ channel currents.NEW & NOTEWORTHY The effects of external pH changes on spontaneous, miniature, and evoked excitatory synaptic transmission in CA3 hippocampal synapses were examined using the isolated nerve bouton preparation, which allowed for the accurate regulation of extracellular pH at the synapses. Acidification generally reduced transmission, partly via effects on presynaptic Ca2+ channel currents, while alkalization generally enhanced transmission. Both pre- and postsynaptic sites contributed to these effects.
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Affiliation(s)
- Il-Sung Jang
- Department of Pharmacology, School of Dentistry, Kyungpook National University, Daegu, Republic of Korea
| | - Michiko Nakamura
- Department of Pharmacology, School of Dentistry, Kyungpook National University, Daegu, Republic of Korea
| | - Hisahiko Kubota
- Department of Pharmacology, Faculty of Medicine, Saga University, Saga, Japan
| | - Mami Noda
- Laboratory of Pathophysiology, Graduate School of Pharmaceutical Sciences, Kyushu University, Fukuoka, Japan
| | - Norio Akaike
- Research Division for Clinical Pharmacology, Medical Corporation, Juryo Group, Kumamoto Kinoh Hospital, Kumamoto, Japan.,Research Division of Neurophysiology, Kitamoto Hospital, Saitama, Japan
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The Perlman syndrome DIS3L2 exoribonuclease safeguards endoplasmic reticulum-targeted mRNA translation and calcium ion homeostasis. Nat Commun 2020; 11:2619. [PMID: 32457326 PMCID: PMC7250864 DOI: 10.1038/s41467-020-16418-y] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2019] [Accepted: 04/30/2020] [Indexed: 11/16/2022] Open
Abstract
DIS3L2-mediated decay (DMD) is a surveillance pathway for certain non-coding RNAs (ncRNAs) including ribosomal RNAs (rRNAs), transfer RNAs (tRNAs), small nuclear RNAs (snRNAs), and RMRP. While mutations in DIS3L2 are associated with Perlman syndrome, the biological significance of impaired DMD is obscure and pathological RNAs have not been identified. Here, by ribosome profiling (Ribo-seq) we find specific dysregulation of endoplasmic reticulum (ER)-targeted mRNA translation in DIS3L2-deficient cells. Mechanistically, DMD functions in the quality control of the 7SL ncRNA component of the signal recognition particle (SRP) required for ER-targeted translation. Upon DIS3L2 loss, sustained 3’-end uridylation of aberrant 7SL RNA impacts ER-targeted translation and causes ER calcium leakage. Consequently, elevated intracellular calcium in DIS3L2-deficient cells activates calcium signaling response genes and perturbs ESC differentiation. Thus, DMD is required to safeguard ER-targeted mRNA translation, intracellular calcium homeostasis, and stem cell differentiation. The DIS3L2 exonuclease degrades aberrant 7SL RNAs tagged by an oligouridine 3′-tail. Here the authors analyze DIS3L2 knockout mouse embryonic stem cells and suggest that DIS3L2-mediated quality control of 7SL RNA is important for ER-mediated translation and calcium ion homeostasis.
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Carbon Monoxide, a Retrograde Messenger Generated in Postsynaptic Mushroom Body Neurons, Evokes Noncanonical Dopamine Release. J Neurosci 2020; 40:3533-3548. [PMID: 32253360 DOI: 10.1523/jneurosci.2378-19.2020] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2019] [Revised: 02/12/2020] [Accepted: 03/19/2020] [Indexed: 02/06/2023] Open
Abstract
Dopaminergic neurons innervate extensive areas of the brain and release dopamine (DA) onto a wide range of target neurons. However, DA release is also precisely regulated. In Drosophila melanogaster brain explant preparations, DA is released specifically onto α3/α'3 compartments of mushroom body (MB) neurons that have been coincidentally activated by cholinergic and glutamatergic inputs. The mechanism for this precise release has been unclear. Here we found that coincidentally activated MB neurons generate carbon monoxide (CO), which functions as a retrograde signal evoking local DA release from presynaptic terminals. CO production depends on activity of heme oxygenase in postsynaptic MB neurons, and CO-evoked DA release requires Ca2+ efflux through ryanodine receptors in DA terminals. CO is only produced in MB areas receiving coincident activation, and removal of CO using scavengers blocks DA release. We propose that DA neurons use two distinct modes of transmission to produce global and local DA signaling.SIGNIFICANCE STATEMENT Dopamine (DA) is needed for various higher brain functions, including memory formation. However, DA neurons form extensive synaptic connections, while memory formation requires highly specific and localized DA release. Here we identify a mechanism through which DA release from presynaptic terminals is controlled by postsynaptic activity. Postsynaptic neurons activated by cholinergic and glutamatergic inputs generate carbon monoxide, which acts as a retrograde messenger inducing presynaptic DA release. Released DA is required for memory-associated plasticity. Our work identifies a novel mechanism that restricts DA release to the specific postsynaptic sites that require DA during memory formation.
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Kawano H, Mitchell SB, Koh JY, Goodman KM, Harata NC. Calcium-induced calcium release in noradrenergic neurons of the locus coeruleus. Brain Res 2020; 1729:146627. [PMID: 31883849 DOI: 10.1016/j.brainres.2019.146627] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2019] [Revised: 12/19/2019] [Accepted: 12/24/2019] [Indexed: 12/11/2022]
Abstract
The locus coeruleus (LC) is a nucleus within the brainstem that consists of norepinephrine-releasing neurons. It is involved in broad processes including cognitive and emotional functions. Understanding the mechanisms that control the excitability of LC neurons is important because they innervate widespread brain regions. One of the key regulators is cytosolic calcium concentration ([Ca2+]c), the increases in which can be amplified by calcium-induced calcium release (CICR) from intracellular calcium stores. Although the electrical activities of LC neurons are regulated by changes in [Ca2+]c, the extent of CICR involvement in this regulation has remained unclear. Here we show that CICR hyperpolarizes acutely dissociated LC neurons of the rat and demonstrate the underlying pathway. When CICR was activated by extracellular application of 10 mM caffeine, LC neurons were hyperpolarized in the current-clamp mode of patch-clamp recording, and the majority of neurons showed an outward current in the voltage-clamp mode. This outward current was accompanied by increased membrane conductance, and its reversal potential was close to the K+ equilibrium potential, indicating that it is mediated by opening of K+ channels. The outward current was generated in the absence of extracellular calcium and was blocked when the calcium stores were inhibited by applying ryanodine. Pharmacological blockers indicated that it was mediated by Ca2+-activated K+ channels of the non-small conductance type. The application of caffeine increased [Ca2+]c, as visualized by fluorescence microscopy. These findings show CICR suppresses LC neuronal activity, and indicate its dynamic role in modulating the LC-mediated noradrenergic tone in the brain.
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Affiliation(s)
- Hiroyuki Kawano
- Department of Molecular Physiology and Biophysics, University of Iowa Carver College of Medicine, Iowa City, IA, USA
| | - Sara B Mitchell
- Department of Molecular Physiology and Biophysics, University of Iowa Carver College of Medicine, Iowa City, IA, USA
| | - Jin-Young Koh
- Department of Molecular Physiology and Biophysics, University of Iowa Carver College of Medicine, Iowa City, IA, USA; Molecular Otolaryngology and Renal Research Laboratories, Department of Otolaryngology-Head and Neck Surgery, University of Iowa Carver College of Medicine, Iowa City, IA, USA; Department of Biomedical Engineering, University of Iowa College of Engineering, Iowa City, IA, USA
| | - Kirsty M Goodman
- Department of Molecular Physiology and Biophysics, University of Iowa Carver College of Medicine, Iowa City, IA, USA; Department of Biology & Biochemistry, University of Bath, Bath, UK
| | - N Charles Harata
- Department of Molecular Physiology and Biophysics, University of Iowa Carver College of Medicine, Iowa City, IA, USA.
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Kikuta S, Iguchi Y, Kakizaki T, Kobayashi K, Yanagawa Y, Takada M, Osanai M. Store-Operated Calcium Channels Are Involved in Spontaneous Slow Calcium Oscillations in Striatal Neurons. Front Cell Neurosci 2019; 13:547. [PMID: 31920549 PMCID: PMC6927941 DOI: 10.3389/fncel.2019.00547] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2019] [Accepted: 11/25/2019] [Indexed: 12/19/2022] Open
Abstract
The striatum plays an important role in linking cortical activity to basal ganglia output. Striatal neurons exhibit spontaneous slow Ca2+ oscillations that result from Ca2+ release from the endoplasmic reticulum (ER) induced by the mGluR5-IP3R signaling cascade. The maximum duration of a single oscillatory event is about 300 s. A major question arises as to how such a long-duration Ca2+ elevation is maintained. Store-operated calcium channels (SOCCs) are one of the calcium (Ca2+)-permeable ion channels. SOCCs are opened by activating the metabotropic glutamate receptor type 5 and inositol 1,4,5-trisphosphate receptor (mGluR5-IP3R) signal transduction cascade and are related to the pathophysiology of several neurological disorders. However, the functions of SOCCs in striatal neurons remain unclear. Here, we show that SOCCs exert a functional role in striatal GABAergic neurons. Depletion of calcium stores from the ER induced large, sustained calcium entry that was blocked by SKF96365, an inhibitor of SOCCs. Moreover, the application of SKF96365 greatly reduced the frequency of slow Ca2+ oscillations. The present results indicate that SOCCs contribute to Ca2+ signaling in striatal GABAergic neurons, including medium spiny projection neurons (MSNs) and GABAergic interneurons, through elevated Ca2+ due to spontaneous slow Ca2+ oscillations.
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Affiliation(s)
- Satomi Kikuta
- Department of Radiological Imaging and Informatics, Tohoku University Graduate School of Medicine, Sendai, Japan.,Systems Neuroscience Section, Primate Research Institute, Kyoto University, Inuyama, Japan.,Research Fellow of Japan Society for the Promotion of Science, Tokyo, Japan
| | - Yoshio Iguchi
- Department of Molecular Genetics, Institute of Biomedical Sciences, Fukushima Medical University School of Medicine, Fukushima, Japan
| | - Toshikazu Kakizaki
- Department of Genetic and Behavioral Neuroscience, Gunma University Graduate School of Medicine, Maebashi, Japan
| | - Kazuto Kobayashi
- Department of Molecular Genetics, Institute of Biomedical Sciences, Fukushima Medical University School of Medicine, Fukushima, Japan
| | - Yuchio Yanagawa
- Department of Genetic and Behavioral Neuroscience, Gunma University Graduate School of Medicine, Maebashi, Japan
| | - Masahiko Takada
- Systems Neuroscience Section, Primate Research Institute, Kyoto University, Inuyama, Japan
| | - Makoto Osanai
- Department of Radiological Imaging and Informatics, Tohoku University Graduate School of Medicine, Sendai, Japan.,Laboratory for Physiological Functional Imaging, Department of Medical Physics and Engineering, Division of Health Sciences, Osaka University Graduate School of Medicine, Suita, Japan
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20
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Mahajan G, Nadkarni S. Intracellular calcium stores mediate metaplasticity at hippocampal dendritic spines. J Physiol 2019; 597:3473-3502. [PMID: 31099020 PMCID: PMC6636706 DOI: 10.1113/jp277726] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2019] [Accepted: 05/16/2019] [Indexed: 12/21/2022] Open
Abstract
Key points Calcium (Ca2+) entry mediated by NMDA receptors is considered central to the induction of activity‐dependent synaptic plasticity in hippocampal area CA1; this description does not, however, take into account the potential contribution of endoplasmic reticulum (ER) Ca2+ stores. The ER has a heterogeneous distribution in CA1 dendritic spines, and may introduce localized functional differences in Ca2+ signalling between synapses, as suggested by experiments on metabotropic receptor‐dependent long‐term depression. A physiologically detailed computational model of Ca2+ dynamics at a CA3–CA1 excitatory synapse characterizes the contribution of spine ER via metabotropic signalling during plasticity induction protocols. ER Ca2+ release via IP3 receptors modulates NMDA receptor‐dependent plasticity in a graded manner, to selectively promote synaptic depression with relatively diminished effect on LTP induction; this may temper further strengthening at the stronger synapses which are preferentially associated with ER‐containing spines. Acquisition of spine ER may thus represent a local, biophysically plausible ‘metaplastic switch’ at potentiated CA1 synapses, contributing to the plasticity–stability balance in neural circuits.
Abstract Long‐term plasticity mediated by NMDA receptors supports input‐specific, Hebbian forms of learning at excitatory CA3–CA1 connections in the hippocampus. There exists an additional layer of stabilizing mechanisms that act globally as well as locally over multiple time scales to ensure that plasticity occurs in a constrained manner. Here, we investigated the role of calcium (Ca2+) stores associated with the endoplasmic reticulum (ER) in the local regulation of plasticity at individual CA1 synapses. Our study was spurred by (1) the curious observation that ER is sparsely distributed in dendritic spines, but over‐represented in larger spines that are likely to have undergone activity‐dependent strengthening, and (2) evidence suggesting that ER motility at synapses can be rapid, and accompany activity‐regulated spine remodelling. We constructed a physiologically realistic computational model of an ER‐bearing CA1 spine, and examined how IP3‐sensitive Ca2+ stores affect spine Ca2+ dynamics during activity patterns mimicking the induction of long‐term potentiation and long‐term depression (LTD). Our results suggest that the presence of ER modulates NMDA receptor‐dependent plasticity in a graded manner that selectively enhances LTD induction. We propose that ER may locally tune Ca2+‐based plasticity, providing a braking mechanism to mitigate runaway strengthening at potentiated synapses. Our study provides a biophysically accurate description of postsynaptic Ca2+ regulation, and suggests that ER in the spine may promote the re‐use of hippocampal synapses with saturated strengths. Calcium (Ca2+) entry mediated by NMDA receptors is considered central to the induction of activity‐dependent synaptic plasticity in hippocampal area CA1; this description does not, however, take into account the potential contribution of endoplasmic reticulum (ER) Ca2+ stores. The ER has a heterogeneous distribution in CA1 dendritic spines, and may introduce localized functional differences in Ca2+ signalling between synapses, as suggested by experiments on metabotropic receptor‐dependent long‐term depression. A physiologically detailed computational model of Ca2+ dynamics at a CA3–CA1 excitatory synapse characterizes the contribution of spine ER via metabotropic signalling during plasticity induction protocols. ER Ca2+ release via IP3 receptors modulates NMDA receptor‐dependent plasticity in a graded manner, to selectively promote synaptic depression with relatively diminished effect on LTP induction; this may temper further strengthening at the stronger synapses which are preferentially associated with ER‐containing spines. Acquisition of spine ER may thus represent a local, biophysically plausible ‘metaplastic switch’ at potentiated CA1 synapses, contributing to the plasticity–stability balance in neural circuits.
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Affiliation(s)
- Gaurang Mahajan
- Indian Institute of Science Education and Research, Pune, 411 008, India
| | - Suhita Nadkarni
- Indian Institute of Science Education and Research, Pune, 411 008, India
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Borczyk M, Śliwińska MA, Caly A, Bernas T, Radwanska K. Neuronal plasticity affects correlation between the size of dendritic spine and its postsynaptic density. Sci Rep 2019; 9:1693. [PMID: 30737431 PMCID: PMC6368589 DOI: 10.1038/s41598-018-38412-7] [Citation(s) in RCA: 57] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2018] [Accepted: 11/19/2018] [Indexed: 01/23/2023] Open
Abstract
Structural plasticity of dendritic spines is thought to underlie memory formation. Size of a dendritic spine is considered proportional to the size of its postsynaptic density (PSD), number of glutamate receptors and synaptic strength. However, whether this correlation is true for all dendritic spine volumes, and remains stable during synaptic plasticity, is largely unknown. In this study, we take advantage of 3D electron microscopy and reconstruct dendritic spines and cores of PSDs from the stratum radiatum of the area CA1 of organotypic hippocampal slices. We observe that approximately 1/3 of dendritic spines, in a range of medium sizes, fail to reach significant correlation between dendritic spine volume and PSD surface area or PSD-core volume. During NMDA receptor-dependent chemical long-term potentiation (NMDAR-cLTP) dendritic spines and their PSD not only grow, but also PSD area and PSD-core volume to spine volume ratio is increased, and the correlation between the sizes of these two is tightened. Further analysis specified that only spines that contain smooth endoplasmic reticulum (SER) grow during cLTP, while PSD-cores grow irrespectively of the presence of SER in the spine. Dendritic spines with SER also show higher correlation of the volumetric parameters than spines without SER, and this correlation is further increased during cLTP only in the spines that contain SER. Overall, we found that correlation between PSD surface area and spine volume is not consistent across all spine volumes, is modified and tightened during synaptic plasticity and regulated by SER.
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Affiliation(s)
- Malgorzata Borczyk
- Laboratory of Molecular Basis of Behavior, the Nencki Institute of Experimental Biology of Polish Academy of Sciences, ul. L. Pasteura 3, Warsaw, 02-093, Poland
| | - Małgorzata Alicja Śliwińska
- Laboratory of Molecular Basis of Behavior, the Nencki Institute of Experimental Biology of Polish Academy of Sciences, ul. L. Pasteura 3, Warsaw, 02-093, Poland.,Laboratory of Imaging Tissue Structure and Function, the Nencki Institute of Experimental Biology of Polish Academy of Sciences, ul. L. Pasteura 3, Warsaw, 02-093, Poland
| | - Anna Caly
- Laboratory of Molecular Basis of Behavior, the Nencki Institute of Experimental Biology of Polish Academy of Sciences, ul. L. Pasteura 3, Warsaw, 02-093, Poland
| | - Tytus Bernas
- Laboratory of Imaging Tissue Structure and Function, the Nencki Institute of Experimental Biology of Polish Academy of Sciences, ul. L. Pasteura 3, Warsaw, 02-093, Poland
| | - Kasia Radwanska
- Laboratory of Molecular Basis of Behavior, the Nencki Institute of Experimental Biology of Polish Academy of Sciences, ul. L. Pasteura 3, Warsaw, 02-093, Poland.
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22
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Chakroborty S, Hill ES, Christian DT, Helfrich R, Riley S, Schneider C, Kapecki N, Mustaly-Kalimi S, Seiler FA, Peterson DA, West AR, Vertel BM, Frost WN, Stutzmann GE. Reduced presynaptic vesicle stores mediate cellular and network plasticity defects in an early-stage mouse model of Alzheimer's disease. Mol Neurodegener 2019; 14:7. [PMID: 30670054 PMCID: PMC6343260 DOI: 10.1186/s13024-019-0307-7] [Citation(s) in RCA: 44] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2018] [Accepted: 01/13/2019] [Indexed: 01/27/2023] Open
Abstract
Background Identifying effective strategies to prevent memory loss in AD has eluded researchers to date, and likely reflects insufficient understanding of early pathogenic mechanisms directly affecting memory encoding. As synaptic loss best correlates with memory loss in AD, refocusing efforts to identify factors driving synaptic impairments may provide the critical insight needed to advance the field. In this study, we reveal a previously undescribed cascade of events underlying pre and postsynaptic hippocampal signaling deficits linked to cognitive decline in AD. These profound alterations in synaptic plasticity, intracellular Ca2+ signaling, and network propagation are observed in 3–4 month old 3xTg-AD mice, an age which does not yet show overt histopathology or major behavioral deficits. Methods In this study, we examined hippocampal synaptic structure and function from the ultrastructural level to the network level using a range of techniques including electron microscopy (EM), patch clamp and field potential electrophysiology, synaptic immunolabeling, spine morphology analyses, 2-photon Ca2+ imaging, and voltage-sensitive dye-based imaging of hippocampal network function in 3–4 month old 3xTg-AD and age/background strain control mice. Results In 3xTg-AD mice, short-term plasticity at the CA1-CA3 Schaffer collateral synapse is profoundly impaired; this has broader implications for setting long-term plasticity thresholds. Alterations in spontaneous vesicle release and paired-pulse facilitation implicated presynaptic signaling abnormalities, and EM analysis revealed a reduction in the ready-releasable and reserve pools of presynaptic vesicles in CA3 terminals; this is an entirely new finding in the field. Concurrently, increased synaptically-evoked Ca2+ in CA1 spines triggered by LTP-inducing tetani is further enhanced during PTP and E-LTP epochs, and is accompanied by impaired synaptic structure and spine morphology. Notably, vesicle stores, synaptic structure and short-term plasticity are restored by normalizing intracellular Ca2+ signaling in the AD mice. Conclusions These findings suggest the Ca2+ dyshomeostasis within synaptic compartments has an early and fundamental role in driving synaptic pathophysiology in early stages of AD, and may thus reflect a foundational disease feature driving later cognitive impairment. The overall significance is the identification of previously unidentified defects in pre and postsynaptic compartments affecting synaptic vesicle stores, synaptic plasticity, and network propagation, which directly impact memory encoding. Electronic supplementary material The online version of this article (10.1186/s13024-019-0307-7) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Shreaya Chakroborty
- Department of Neuroscience, The Chicago Medical School; The Center for Neurodegenerative Disease and Therapeutics, Rosalind Franklin University of Medicine and Science, 3333 Green Bay Rd, North Chicago, IL, 60064, USA
| | - Evan S Hill
- Department of Cell Biology and Anatomy, The Chicago Medical School; Center for Brain Function and Repair, Rosalind Franklin University of Medicine and Science, 3333 Green Bay Rd, North Chicago, IL, 60064, USA
| | - Daniel T Christian
- Department of Neuroscience, The Chicago Medical School; The Center for Neurodegenerative Disease and Therapeutics, Rosalind Franklin University of Medicine and Science, 3333 Green Bay Rd, North Chicago, IL, 60064, USA
| | - Rosalind Helfrich
- Department of Neuroscience, The Chicago Medical School; The Center for Neurodegenerative Disease and Therapeutics, Rosalind Franklin University of Medicine and Science, 3333 Green Bay Rd, North Chicago, IL, 60064, USA
| | - Shannon Riley
- Department of Neuroscience, The Chicago Medical School; The Center for Neurodegenerative Disease and Therapeutics, Rosalind Franklin University of Medicine and Science, 3333 Green Bay Rd, North Chicago, IL, 60064, USA
| | - Corinne Schneider
- Department of Neuroscience, The Chicago Medical School; The Center for Neurodegenerative Disease and Therapeutics, Rosalind Franklin University of Medicine and Science, 3333 Green Bay Rd, North Chicago, IL, 60064, USA
| | - Nicolas Kapecki
- Department of Neuroscience, The Chicago Medical School; The Center for Neurodegenerative Disease and Therapeutics, Rosalind Franklin University of Medicine and Science, 3333 Green Bay Rd, North Chicago, IL, 60064, USA
| | - Sarah Mustaly-Kalimi
- Department of Neuroscience, The Chicago Medical School; The Center for Neurodegenerative Disease and Therapeutics, Rosalind Franklin University of Medicine and Science, 3333 Green Bay Rd, North Chicago, IL, 60064, USA
| | - Figen A Seiler
- Electron Microscopy Center, RFUMS, North Chicago, IL, 60064, USA
| | - Daniel A Peterson
- Department of Neuroscience, The Chicago Medical School; The Center for Neurodegenerative Disease and Therapeutics, Rosalind Franklin University of Medicine and Science, 3333 Green Bay Rd, North Chicago, IL, 60064, USA
| | - Anthony R West
- Department of Neuroscience, The Chicago Medical School; The Center for Neurodegenerative Disease and Therapeutics, Rosalind Franklin University of Medicine and Science, 3333 Green Bay Rd, North Chicago, IL, 60064, USA
| | - Barbara M Vertel
- Department of Cell Biology and Anatomy, The Chicago Medical School; Center for Brain Function and Repair, Rosalind Franklin University of Medicine and Science, 3333 Green Bay Rd, North Chicago, IL, 60064, USA.,Electron Microscopy Center, RFUMS, North Chicago, IL, 60064, USA
| | - William N Frost
- Department of Cell Biology and Anatomy, The Chicago Medical School; Center for Brain Function and Repair, Rosalind Franklin University of Medicine and Science, 3333 Green Bay Rd, North Chicago, IL, 60064, USA
| | - Grace E Stutzmann
- Department of Neuroscience, The Chicago Medical School; The Center for Neurodegenerative Disease and Therapeutics, Rosalind Franklin University of Medicine and Science, 3333 Green Bay Rd, North Chicago, IL, 60064, USA.
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23
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Zhao H, Xu X, Lei S, Shao D, Jiang C, Shi J, Zhang Y, Liu L, Lei S, Sun H, Huang Q. Iturin A‐like lipopeptides from
Bacillus subtilis
trigger apoptosis, paraptosis, and autophagy in Caco‐2 cells. J Cell Physiol 2018; 234:6414-6427. [DOI: 10.1002/jcp.27377] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2018] [Accepted: 08/17/2018] [Indexed: 12/21/2022]
Affiliation(s)
- Haobin Zhao
- Key Laboratory for Space Bioscience and Biotechnology, School of Life Sciences, Northwestern Polytechnical University Xi’an China
| | - Xiaoguang Xu
- Key Laboratory for Space Bioscience and Biotechnology, School of Life Sciences, Northwestern Polytechnical University Xi’an China
| | - Shuzhen Lei
- Key Laboratory for Space Bioscience and Biotechnology, School of Life Sciences, Northwestern Polytechnical University Xi’an China
| | - Dongyan Shao
- Key Laboratory for Space Bioscience and Biotechnology, School of Life Sciences, Northwestern Polytechnical University Xi’an China
| | - Chunmei Jiang
- Key Laboratory for Space Bioscience and Biotechnology, School of Life Sciences, Northwestern Polytechnical University Xi’an China
| | - Junling Shi
- Key Laboratory for Space Bioscience and Biotechnology, School of Life Sciences, Northwestern Polytechnical University Xi’an China
| | - Yawen Zhang
- Key Laboratory for Space Bioscience and Biotechnology, School of Life Sciences, Northwestern Polytechnical University Xi’an China
| | - Li Liu
- Key Laboratory for Space Bioscience and Biotechnology, School of Life Sciences, Northwestern Polytechnical University Xi’an China
| | - Shuzhen Lei
- Key Laboratory for Space Bioscience and Biotechnology, School of Life Sciences, Northwestern Polytechnical University Xi’an China
| | - Hui Sun
- Key Laboratory for Space Bioscience and Biotechnology, School of Life Sciences, Northwestern Polytechnical University Xi’an China
- School of Hospitality Management, Guilin Tourism University Guilin China
| | - Qingsheng Huang
- Key Laboratory for Space Bioscience and Biotechnology, School of Life Sciences, Northwestern Polytechnical University Xi’an China
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More J, Casas MM, Sánchez G, Hidalgo C, Haeger P. Contextual Fear Memory Formation and Destabilization Induce Hippocampal RyR2 Calcium Channel Upregulation. Neural Plast 2018; 2018:5056181. [PMID: 30123252 PMCID: PMC6079367 DOI: 10.1155/2018/5056181] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2018] [Revised: 04/17/2018] [Accepted: 06/03/2018] [Indexed: 12/17/2022] Open
Abstract
Hippocampus-dependent spatial and aversive memory processes entail Ca2+ signals generated by ryanodine receptor (RyR) Ca2+ channels residing in the endoplasmic reticulum membrane. Rodents exposed to different spatial memory tasks exhibit significant hippocampal RyR upregulation. Contextual fear conditioning generates robust hippocampal memories through an associative learning process, but the effects of contextual fear memory acquisition, consolidation, or extinction on hippocampal RyR protein levels remain unreported. Accordingly, here we investigated if exposure of male rats to contextual fear protocols, or subsequent exposure to memory destabilization protocols, modified the hippocampal content of type-2 RyR (RyR2) channels, the predominant hippocampal RyR isoforms that hold key roles in synaptic plasticity and spatial memory processes. We found that contextual memory retention caused a transient increase in hippocampal RyR2 protein levels, determined 5 h after exposure to the conditioning protocol; this increase vanished 29 h after training. Context reexposure 24 h after training, for 3, 15, or 30 min without the aversive stimulus, decreased fear memory and increased RyR2 protein levels, determined 5 h after reexposure. We propose that both fear consolidation and extinction memories induce RyR2 protein upregulation in order to generate the intracellular Ca2+ signals required for these distinct memory processes.
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Affiliation(s)
- Jamileth More
- Biomedical Neuroscience Institute, Faculty of Medicine, Universidad de Chile, Santiago, Chile
| | - María Mercedes Casas
- Biomedical Neuroscience Institute, Faculty of Medicine, Universidad de Chile, Santiago, Chile
| | - Gina Sánchez
- Pathophysiology Program, ICBM, Faculty of Medicine, Universidad de Chile, Santiago, Chile
- Center for Exercise, Metabolism and Cancer, Faculty of Medicine, Universidad de Chile, Santiago, Chile
| | - Cecilia Hidalgo
- Biomedical Neuroscience Institute, Faculty of Medicine, Universidad de Chile, Santiago, Chile
- Center for Exercise, Metabolism and Cancer, Faculty of Medicine, Universidad de Chile, Santiago, Chile
- Department of Neurosciences and Physiology and Biophysics Program, ICBM, Faculty of Medicine, Universidad de Chile, Santiago, Chile
| | - Paola Haeger
- Department of Biomedical Sciences, Faculty of Medicine, Universidad Católica del Norte, Coquimbo, Chile
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25
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Gopurappilly R, Deb BK, Chakraborty P, Hasan G. Stable STIM1 Knockdown in Self-Renewing Human Neural Precursors Promotes Premature Neural Differentiation. Front Mol Neurosci 2018; 11:178. [PMID: 29942250 PMCID: PMC6004407 DOI: 10.3389/fnmol.2018.00178] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2018] [Accepted: 05/09/2018] [Indexed: 12/31/2022] Open
Abstract
Ca2+ signaling plays a significant role in the development of the vertebrate nervous system where it regulates neurite growth as well as synapse and neurotransmitter specification. Elucidating the role of Ca2+ signaling in mammalian neuronal development has been largely restricted to either small animal models or primary cultures. Here we derived human neural precursor cells (NPCs) from human embryonic stem cells to understand the functional significance of a less understood arm of calcium signaling, Store-operated Ca2+ entry or SOCE, in neuronal development. Human NPCs exhibited robust SOCE, which was significantly attenuated by expression of a stable shRNA-miR targeted toward the SOCE molecule, STIM1. Along with the plasma membrane channel Orai, STIM is an essential component of SOCE in many cell types, where it regulates gene expression. Therefore, we measured global gene expression in human NPCs with and without STIM1 knockdown. Interestingly, pathways down-regulated through STIM1 knockdown were related to cell proliferation and DNA replication processes, whereas post-synaptic signaling was identified as an up-regulated process. To understand the functional significance of these gene expression changes we measured the self-renewal capacity of NPCs with STIM1 knockdown. The STIM1 knockdown NPCs demonstrated significantly reduced neurosphere size and number as well as precocious spontaneous differentiation toward the neuronal lineage, as compared to control cells. These findings demonstrate that STIM1 mediated SOCE in human NPCs regulates gene expression changes, that in vivo are likely to physiologically modulate the self-renewal and differentiation of NPCs.
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Affiliation(s)
- Renjitha Gopurappilly
- National Centre for Biological Sciences, Tata Institute of Fundamental Research, Bengaluru, India
| | - Bipan Kumar Deb
- National Centre for Biological Sciences, Tata Institute of Fundamental Research, Bengaluru, India
| | - Pragnya Chakraborty
- National Centre for Biological Sciences, Tata Institute of Fundamental Research, Bengaluru, India
| | - Gaiti Hasan
- National Centre for Biological Sciences, Tata Institute of Fundamental Research, Bengaluru, India
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26
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Huang M, Verbeek DS. Why do so many genetic insults lead to Purkinje Cell degeneration and spinocerebellar ataxia? Neurosci Lett 2018; 688:49-57. [PMID: 29421540 DOI: 10.1016/j.neulet.2018.02.004] [Citation(s) in RCA: 43] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2017] [Accepted: 02/02/2018] [Indexed: 12/29/2022]
Abstract
The genetically heterozygous spinocerebellar ataxias are all characterized by cerebellar atrophy and pervasive Purkinje Cell degeneration. Up to date, more than 35 functionally diverse spinocerebellar ataxia genes have been identified. The main question that remains yet unsolved is why do some many genetic insults lead to Purkinje Cell degeneration and spinocerebellar ataxia? To address this question it is important to identify intrinsic pathways important for Purkinje Cell function and survival. In this review, we discuss the current consensus on shared mechanisms underlying the pervasive Purkinje Cell loss in spinocerebellar ataxia. Additionally, using recently published cell type specific expression data, we identified several Purkinje Cell-specific genes and discuss how the corresponding pathways might underlie the vulnerability of Purkinje Cells in response to the diverse genetic insults causing spinocerebellar ataxia.
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Affiliation(s)
- Miaozhen Huang
- University of Groningen, University Medical Center Groningen, Department of Genetics, Groningen, The Netherlands
| | - Dineke S Verbeek
- University of Groningen, University Medical Center Groningen, Department of Genetics, Groningen, The Netherlands.
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27
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González-Sánchez P, Del Arco A, Esteban JA, Satrústegui J. Store-Operated Calcium Entry Is Required for mGluR-Dependent Long Term Depression in Cortical Neurons. Front Cell Neurosci 2017; 11:363. [PMID: 29311823 PMCID: PMC5735122 DOI: 10.3389/fncel.2017.00363] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2017] [Accepted: 11/03/2017] [Indexed: 01/13/2023] Open
Abstract
Store-operated calcium entry (SOCE) is a Calcium (Ca2+) influx pathway activated by depletion of intracellular stores that occurs in eukaryotic cells. In neurons, the presence and functions of SOCE are still in question. Here, we show evidences for the existence of SOCE in primary mouse cortical neurons. Endoplasmic reticulum (ER)-Ca2+ depletion using thapsigargin (Tg) triggered a maintained cytosolic Ca2+ increase, which rapidly returned to basal level in the presence of the SOCE blockers 2-Aminoethoxydiphenyl borate (2-APB) and YM-58483. Neural SOCE is also engaged by activation of metabotropic glutamate receptors (mGluRs) with (S)-3,5-dihydroxyphenylglycine (DHPG) (agonist of group I mGluRs), being an essential mechanism to maintain the mGluR-driven Ca2+ signal. Activation of group I of mGluRs triggers long-term depression (LTD) in many brain regions, but the underlying mechanism and, specifically, the necessity of Ca2+ increase in the postsynaptic neuron is controversial. In primary cortical neurons, we now show that the inhibition of Ca2+ influx through SOCE impaired DHPG-LTD, pointing out a key function of calcium and SOCE in synaptic plasticity.
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Affiliation(s)
- Paloma González-Sánchez
- Department of Molecular Biology, Centro de Biología Molecular Severo Ochoa, Consejo Superior de Investigaciones Científicas-Universidad Autónoma de Madrid (CSIC-UAM), Madrid, Spain.,Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER), Madrid, Spain.,Instituto de Investigación Sanitaria Fundación Jiménez Díaz (IIS-FJD), Madrid, Spain
| | - Araceli Del Arco
- Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER), Madrid, Spain.,Instituto de Investigación Sanitaria Fundación Jiménez Díaz (IIS-FJD), Madrid, Spain.,Facultad de Ciencias Ambientales y Bioquímica, Universidad de Castilla la Mancha, Toledo, Spain
| | - José A Esteban
- Department of Molecular Neurobiology, Centro de Biología Molecular Severo Ochoa, Consejo Superior de Investigaciones Científicas-Universidad Autónoma de Madrid (CSIC-UAM), Madrid, Spain
| | - Jorgina Satrústegui
- Department of Molecular Biology, Centro de Biología Molecular Severo Ochoa, Consejo Superior de Investigaciones Científicas-Universidad Autónoma de Madrid (CSIC-UAM), Madrid, Spain.,Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER), Madrid, Spain.,Instituto de Investigación Sanitaria Fundación Jiménez Díaz (IIS-FJD), Madrid, Spain
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28
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Extended Synaptotagmin Localizes to Presynaptic ER and Promotes Neurotransmission and Synaptic Growth in Drosophila. Genetics 2017; 207:993-1006. [PMID: 28882990 DOI: 10.1534/genetics.117.300261] [Citation(s) in RCA: 38] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2017] [Accepted: 09/01/2017] [Indexed: 01/08/2023] Open
Abstract
The endoplasmic reticulum (ER) is an extensive organelle in neurons with important roles at synapses including the regulation of cytosolic Ca2+, neurotransmission, lipid metabolism, and membrane trafficking. Despite intriguing evidence for these crucial functions, how the presynaptic ER influences synaptic physiology remains enigmatic. To gain insight into this question, we have generated and characterized mutations in the single extended synaptotagmin (Esyt) ortholog in Drosophila melanogaster Esyts are evolutionarily conserved ER proteins with Ca2+-sensing domains that have recently been shown to orchestrate membrane tethering and lipid exchange between the ER and plasma membrane. We first demonstrate that Esyt localizes to presynaptic ER structures at the neuromuscular junction. Next, we show that synaptic growth, structure, and homeostatic plasticity are surprisingly unperturbed at synapses lacking Esyt expression. However, neurotransmission is reduced in Esyt mutants, consistent with a presynaptic role in promoting neurotransmitter release. Finally, neuronal overexpression of Esyt enhances synaptic growth and the sustainment of the vesicle pool during intense activity, suggesting that increased Esyt levels may modulate the membrane trafficking and/or resting Ca2+ pathways that control synapse extension. Thus, we identify Esyt as a presynaptic ER protein that can promote neurotransmission and synaptic growth, revealing the first in vivo neuronal functions of this conserved gene family.
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29
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A Feed-Forward Mechanism Involving the NOX Complex and RyR-Mediated Ca2+ Release During Axonal Specification. J Neurosci 2017; 36:11107-11119. [PMID: 27798190 DOI: 10.1523/jneurosci.1455-16.2016] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2016] [Accepted: 09/06/2016] [Indexed: 01/16/2023] Open
Abstract
Physiological levels of ROS support neurite outgrowth and axonal specification, but the mechanisms by which ROS are able to shape neurons remain unknown. Ca2+, a broad intracellular second messenger, promotes both Rac1 activation and neurite extension. Ca2+ release from the endoplasmic reticulum, mediated by both the IP3R1 and ryanodine receptor (RyR) channels, requires physiological ROS levels that are mainly sustained by the NADPH oxidase (NOX) complex. In this work, we explore the contribution of the link between NOX and RyR-mediated Ca2+ release toward axonal specification of rat hippocampal neurons. Using genetic approaches, we find that NOX activation promotes both axonal development and Rac1 activation through a RyR-mediated mechanism, which in turn activates NOX through Rac1, one of the NOX subunits. Collectively, these data suggest a feedforward mechanism that integrates both NOX activity and RyR-mediated Ca2+ release to support cellular mechanisms involved in axon development. SIGNIFICANCE STATEMENT High levels of ROS are frequently associated with oxidative stress and disease. In contrast, physiological levels of ROS, mainly sustained by the NADPH oxidase (NOX) complex, promote neuronal development and axonal growth. However, the mechanisms by which ROS shape neurons have not been described. Our work suggests that NOX-derived ROS promote axonal growth by regulating Rac1 activity, a molecular determinant of axonal growth, through a ryanodine receptor (RyR)-mediated Ca2+ release mechanism. In addition, Rac1, one of the NOX subunits, was activated after RyR-mediated Ca2+ release, suggesting a feedforward mechanism between NOX and RyR. Collectively, our data suggest a novel mechanism that is instrumental in sustaining physiological levels of ROS required for axonal growth of hippocampal neurons.
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30
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Galaj E, Nisanov R, Ranaldi R. Blockade of muscarinic acetylcholine receptors in the ventral tegmental area blocks the acquisition of reward-related learning. Behav Brain Res 2017; 329:20-25. [PMID: 28442362 DOI: 10.1016/j.bbr.2017.04.037] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2017] [Accepted: 04/17/2017] [Indexed: 12/15/2022]
Abstract
In the present study we investigated whether stimulation of muscarinic acetylcholine (mACh) receptors in the ventral tegmental area (VTA) plays a role in the acquisition of food-based conditioned approach learning. Rats were exposed to 3 (in Experiment 1) or 7 (in Experiment 2) conditioning sessions in which 30, randomly presented light (CS) presentations were paired with delivery of food pellets (US), followed by one session with no light or food and finally one CS-only test session with only light stimulus presentations. Bilateral microinjections of scopolamine (a mACh receptor antagonist) were made either prior to each conditioning session (Experiment 1; to test effects on acquisition) or prior to the CS-only test (Experiment 2; to test effects on performance of the learned response). Scopolamine produced a dose-related significant reduction in the acquisition of conditioned approach but had no effect on its performance. These results suggest that mACh receptor stimulation in the VTA plays a necessary role in the acquisition of reward-related learning.
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Affiliation(s)
- E Galaj
- Neuropsychology Doctoral Program, The Graduate Center of the City University of New York, New York, NY 10016, USA
| | - R Nisanov
- Neuropsychology Doctoral Program, The Graduate Center of the City University of New York, New York, NY 10016, USA
| | - R Ranaldi
- Neuropsychology Doctoral Program, The Graduate Center of the City University of New York, New York, NY 10016, USA; Department of Psychology, Queens College, City University of New York, Flushing NY 11367, USA.
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31
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Mukunda CL, Narayanan R. Degeneracy in the regulation of short-term plasticity and synaptic filtering by presynaptic mechanisms. J Physiol 2017; 595:2611-2637. [PMID: 28026868 DOI: 10.1113/jp273482] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2016] [Accepted: 12/13/2016] [Indexed: 12/14/2022] Open
Abstract
KEY POINTS We develop a new biophysically rooted, physiologically constrained conductance-based synaptic model to mechanistically account for short-term facilitation and depression, respectively through residual calcium and transmitter depletion kinetics. We address the specific question of how presynaptic components (including voltage-gated ion channels, pumps, buffers and release-handling mechanisms) and interactions among them define synaptic filtering and short-term plasticity profiles. Employing global sensitivity analyses (GSAs), we show that near-identical synaptic filters and short-term plasticity profiles could emerge from disparate presynaptic parametric combinations with weak pairwise correlations. Using virtual knockout models, a technique to address the question of channel-specific contributions within the GSA framework, we unveil the differential and variable impact of each ion channel on synaptic physiology. Our conclusions strengthen the argument that parametric and interactional complexity in biological systems should not be viewed from the limited curse-of-dimensionality standpoint, but from the evolutionarily advantageous perspective of providing functional robustness through degeneracy. ABSTRACT Information processing in neurons is known to emerge as a gestalt of pre- and post-synaptic filtering. However, the impact of presynaptic mechanisms on synaptic filters has not been quantitatively assessed. Here, we developed a biophysically rooted, conductance-based model synapse that was endowed with six different voltage-gated ion channels, calcium pumps, calcium buffer and neurotransmitter-replenishment mechanisms in the presynaptic terminal. We tuned our model to match the short-term plasticity profile and band-pass structure of Schaffer collateral synapses, and performed sensitivity analyses to demonstrate that presynaptic voltage-gated ion channels regulated synaptic filters through changes in excitability and associated calcium influx. These sensitivity analyses also revealed that calcium- and release-control mechanisms were effective regulators of synaptic filters, but accomplished this without changes in terminal excitability or calcium influx. Next, to perform global sensitivity analysis, we generated 7000 randomized models spanning 15 presynaptic parameters, and computed eight different physiological measurements in each of these models. We validated these models by applying experimentally obtained bounds on their measurements, and found 104 (∼1.5%) models to match the validation criteria for all eight measurements. Analysing these valid models, we demonstrate that analogous synaptic filters emerge from disparate combinations of presynaptic parameters exhibiting weak pairwise correlations. Finally, using virtual knockout models, we establish the variable and differential impact of different presynaptic channels on synaptic filters, underlining the critical importance of interactions among different presynaptic components in defining synaptic physiology. Our results have significant implications for protein-localization strategies required for physiological robustness and for degeneracy in long-term synaptic plasticity profiles.
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Affiliation(s)
- Chinmayee L Mukunda
- Cellular Neurophysiology Laboratory, Molecular Biophysics Unit, Indian Institute of Science, Bangalore, 560012, India
| | - Rishikesh Narayanan
- Cellular Neurophysiology Laboratory, Molecular Biophysics Unit, Indian Institute of Science, Bangalore, 560012, India
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32
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Sexual Dimorphism in a Reciprocal Interaction of Ryanodine and IP 3 Receptors in the Induction of Hyperalgesic Priming. J Neurosci 2017; 37:2032-2044. [PMID: 28115480 DOI: 10.1523/jneurosci.2911-16.2017] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2016] [Revised: 01/12/2017] [Accepted: 01/13/2017] [Indexed: 12/15/2022] Open
Abstract
Hyperalgesic priming, a model of pain chronification in the rat, is mediated by ryanodine receptor-dependent calcium release. Although ryanodine induces priming in both sexes, females are 5 orders of magnitude more sensitive, by an estrogen receptor α (EsRα)-dependent mechanism. An inositol 1,4,5-triphosphate (IP3) receptor inhibitor prevented the induction of priming by ryanodine. For IP3 induced priming, females were also more sensitive. IP3-induced priming was prevented by pretreatment with inhibitors of the sarcoendoplasmic reticulum calcium ATPase and ryanodine receptor. Antisense to EsRα prevented the induction of priming by low-dose IP3 in females. The induction of priming by an EsRα agonist was ryanodine receptor-dependent and prevented by the IP3 antagonist. Thus, an EsRα-dependent bidirectional interaction between endoplasmic reticulum IP3 and ryanodine receptor-mediated calcium signaling is present in the induction of hyperalgesic priming, in females. In cultured male DRG neurons, IP3 (100 μm) potentiated depolarization-induced transients produced by extracellular application of high-potassium solution (20 mm, K20), in nociceptors incubated with β-estradiol. This potentiation of depolarization-induced calcium transients was blocked by the IP3 antagonist, and not observed in the absence of IP3 IP3 potentiation was also blocked by ryanodine receptor antagonist. The application of ryanodine (2 nm), instead of IP3, also potentiated K20-induced calcium transients in the presence of β-estradiol, in an IP3 receptor-dependent manner. Our results point to an EsRα-dependent, reciprocal interaction between IP3 and ryanodine receptors that contributes to sex differences in hyperalgesic priming.SIGNIFICANCE STATEMENT The present study demonstrates a mechanism that plays a role in the marked sexual dimorphism observed in a model of the transition to chronic pain, hyperalgesic priming. This mechanism involves a reciprocal interaction between the endoplasmic reticulum receptors, IP3 and ryanodine, in the induction of priming, regulated by estrogen receptor α in the nociceptor of female rats. The presence of this signaling pathway modulating the susceptibility of nociceptors to develop plasticity may contribute to our understanding of sex differences observed clinically in chronic pain syndromes.
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33
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Hosseini N, Alaei H, Reisi P, Radahmadi M. The effects of NBM- lesion on synaptic plasticity in rats. Brain Res 2017; 1655:122-127. [DOI: 10.1016/j.brainres.2016.11.013] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2016] [Revised: 10/20/2016] [Accepted: 11/11/2016] [Indexed: 01/01/2023]
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34
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Kwon SK, Hirabayashi Y, Polleux F. Organelle-Specific Sensors for Monitoring Ca 2+ Dynamics in Neurons. Front Synaptic Neurosci 2016; 8:29. [PMID: 27695411 PMCID: PMC5025517 DOI: 10.3389/fnsyn.2016.00029] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2016] [Accepted: 08/30/2016] [Indexed: 11/16/2022] Open
Abstract
Calcium (Ca2+) plays innumerable critical functions in neurons ranging from regulation of neurotransmitter release and synaptic plasticity to activity-dependent transcription. Therefore, more than any other cell types, neurons are critically dependent on spatially and temporally controlled Ca2+ dynamics. This is achieved through an exquisite level of compartmentalization of Ca2+ storage and release from various organelles. The function of these organelles in the regulation of Ca2+ dynamics has been studied for decades using electrophysiological and optical methods combined with pharmacological and genetic alterations. Mitochondria and the endoplasmic reticulum (ER) are among the organelles playing the most critical roles in Ca2+ dynamics in neurons. At presynaptic boutons, Ca2+ triggers neurotransmitter release and synaptic plasticity, and postsynaptically, Ca2+ mobilization mediates long-term synaptic plasticity. To explore Ca2+ dynamics in live cells and intact animals, various synthetic and genetically encoded fluorescent Ca2+ sensors were developed, and recently, many groups actively increased the sensitivity and diversity of genetically encoded Ca2+ indicators (GECIs). Following conjugation with various signal peptides, these improved GECIs can be targeted to specific subcellular compartments, allowing monitoring of organelle-specific Ca2+ dynamics. Here, we review recent findings unraveling novel roles for mitochondria- and ER-dependent Ca2+ dynamics in neurons and at synapses.
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Affiliation(s)
- Seok-Kyu Kwon
- Department of Neuroscience, Mortimer B. Zuckerman Mind Brain Behavior Institute, Kavli Institute for Brain Science, Columbia University Medical Center New York, NY, USA
| | - Yusuke Hirabayashi
- Department of Neuroscience, Mortimer B. Zuckerman Mind Brain Behavior Institute, Kavli Institute for Brain Science, Columbia University Medical Center New York, NY, USA
| | - Franck Polleux
- Department of Neuroscience, Mortimer B. Zuckerman Mind Brain Behavior Institute, Kavli Institute for Brain Science, Columbia University Medical Center New York, NY, USA
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35
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Yap KAF, Shetty MS, Garcia-Alvarez G, Lu B, Alagappan D, Oh-Hora M, Sajikumar S, Fivaz M. STIM2 regulates AMPA receptor trafficking and plasticity at hippocampal synapses. Neurobiol Learn Mem 2016; 138:54-61. [PMID: 27544849 DOI: 10.1016/j.nlm.2016.08.007] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2016] [Revised: 08/14/2016] [Accepted: 08/16/2016] [Indexed: 10/21/2022]
Abstract
STIM2 is an integral membrane protein of the endoplasmic reticulum (ER) that regulates the activity of plasma membrane (PM) channels at ER-PM contact sites. Recent studies show that STIM2 promotes spine maturation and surface expression of the AMPA receptor (AMPAR) subunit GluA1, hinting at a probable role in synaptic plasticity. Here, we used a Stim2 cKO mouse to explore the function of STIM2 in Long-Term Potentiation (LTP) and Depression (LTD), two widely-studied models of synaptic plasticity implicated in information storage. We found that STIM2 is required for the stable expression of both LTP and LTD at CA3-CA1 hippocampal synapses. Altered plasticity in Stim2 cKO mice is associated with subtle alterations in the shape and density of dendritic spines in CA1 neurons. Further, surface delivery of GluA1 in response to LTP-inducing chemical manipulations was markedly reduced in excitatory neurons derived from Stim2 cKO mice. GluA1 endocytosis following chemically-induced LTD was also impaired in Stim2 cKO neurons. We conclude that STIM2 facilitates synaptic delivery and removal of AMPARs and regulates activity-dependent changes in synaptic strength through a unique mode of communication between the ER and the synapse.
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Affiliation(s)
- Kenrick An Fu Yap
- Duke-NUS Medical School, programme in Neuroscience and Behavioral Disorders, Singapore 169857, Singapore
| | - Mahesh Shivarama Shetty
- Department of Physiology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore
| | - Gisela Garcia-Alvarez
- Duke-NUS Medical School, programme in Neuroscience and Behavioral Disorders, Singapore 169857, Singapore
| | - Bo Lu
- Duke-NUS Medical School, programme in Neuroscience and Behavioral Disorders, Singapore 169857, Singapore
| | - Durgadevi Alagappan
- Duke-NUS Medical School, programme in Neuroscience and Behavioral Disorders, Singapore 169857, Singapore
| | - Masatsugu Oh-Hora
- Division of Molecular Immunology, Medical Institute of Bioregulation, Kyushu University, Japan
| | - Sreedharan Sajikumar
- Department of Physiology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore.
| | - Marc Fivaz
- Duke-NUS Medical School, programme in Neuroscience and Behavioral Disorders, Singapore 169857, Singapore; Department of Physiology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore.
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36
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Ryanodine receptors contribute to the induction of ischemic tolerance. Brain Res Bull 2016; 122:45-53. [DOI: 10.1016/j.brainresbull.2016.02.018] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2015] [Revised: 12/14/2015] [Accepted: 02/24/2016] [Indexed: 11/21/2022]
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37
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Abstract
Alzheimer disease (AD) is a fatal progressive disease and the most common form of dementia without effective treatments. Previous studies support that the disruption of endoplasmic reticulum Ca through overactivation of ryanodine receptors plays an important role in the pathogenesis of AD. Normalization of intracellular Ca homeostasis could be an effective strategy for AD therapies. Dantrolene, an antagonist of ryanodine receptors and an FDA-approved drug for clinical treatment of malignant hyperthermia and muscle spasms, exhibits neuroprotective effects in multiple models of neurodegenerative disorders. Recent preclinical studies consistently support the therapeutic effects of dantrolene in various types of AD animal models and were summarized in the current review.
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Zhang Q, Lv X, Wu T, Ma Q, Teng A, Zhang Y, Zhang M. Composition of Lycium barbarum polysaccharides and their apoptosis-inducing effect on human hepatoma SMMC-7721 cells. Food Nutr Res 2015; 59:28696. [PMID: 26563650 PMCID: PMC4643179 DOI: 10.3402/fnr.v59.28696] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2015] [Revised: 10/10/2015] [Accepted: 10/15/2015] [Indexed: 01/04/2023] Open
Abstract
Background Lycium barbarum polysaccharide (LBP) is a natural functional component that has a variety of biological activities. The molecular structures and apoptosis-inducing activities on human hepatoma SMMC-7721 cells of two LBP fractions, LBP-d and LBP-e, were investigated. Results The results showed that LBP-d and LBP-e both consist of protein, uronic acid, and neutral sugars in different proportions. The structure of LBP was characterized by gas chromatography, periodate oxidation, and Smith degradation. LBP-d was composed of eight kinds of monosaccharides (fucose, ribose, rhamnose, arabinose, xylose, mannose, galactose, and glucose), while LBP-e was composed of six kinds of monosaccharides (fucose, rhamnose, arabinose, mannose, galactose, and glucose). LBP-d and LBP-e blocked SMMC-7721 cells at the G0/G1 and S phases with an inhibition ratio of 26.70 and 45.13%, respectively, and enhanced the concentration of Ca2+ in the cytoplasm of SMMC-7721. Conclusion The contents of protein, uronic acid, and galactose in LBP-e were much higher than those in LBP-d, which might responsible for their different bioactivities. The results showed that LBP can be provided as a potential chemotherapeutic agent drug to treat cancer.
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Affiliation(s)
- Qian Zhang
- Key Laboratory of Food Nutrition and Safety (Tianjin University of Science and Technology), Ministry of Education, Tianjin, China.,Department of Biological and Food Engineering, Tianshi College, Tianjin, China
| | - Xiaoling Lv
- Key Laboratory of Food Nutrition and Safety (Tianjin University of Science and Technology), Ministry of Education, Tianjin, China
| | - Tao Wu
- Key Laboratory of Food Nutrition and Safety (Tianjin University of Science and Technology), Ministry of Education, Tianjin, China
| | - Qian Ma
- Key Laboratory of Food Nutrition and Safety (Tianjin University of Science and Technology), Ministry of Education, Tianjin, China
| | - Anguo Teng
- Key Laboratory of Food Nutrition and Safety (Tianjin University of Science and Technology), Ministry of Education, Tianjin, China
| | - Ying Zhang
- Key Laboratory of Food Nutrition and Safety (Tianjin University of Science and Technology), Ministry of Education, Tianjin, China
| | - Min Zhang
- Key Laboratory of Food Nutrition and Safety (Tianjin University of Science and Technology), Ministry of Education, Tianjin, China;
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Segal M, Korkotian E. Roles of Calcium Stores and Store-Operated Channels in Plasticity of Dendritic Spines. Neuroscientist 2015; 22:477-85. [PMID: 26511041 DOI: 10.1177/1073858415613277] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Calcium stores in the endoplasmic reticulum play important roles in a variety of mammalian cellular functions. However, the multitude of calcium-handling machineries in neurons, including voltage- and ligand-gated channels, calcium-binding proteins, pumps, and transporters, as well as the rapid mobility of calcium ions among different cellular compartments hampered the singling out of calcium stores as a pivotal player in synaptic plasticity. Despite these methodological obstacles, novel molecular and imaging tools afforded a rapid progress in deciphering the role of specific calcium stores in neuronal functions. In the present review, we will address several key issues related to the involvement of ryanodine receptors and the calcium entry channel Orai1 in dendritic spine development and plasticity as well as their derailing in neurodegenerative diseases.
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Affiliation(s)
- Menahem Segal
- Department of Neurobiology, The Weizmann Institute, Rehovot, Israel
| | - Eduard Korkotian
- Department of Neurobiology, The Weizmann Institute, Rehovot, Israel
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Castellano-Muñoz M, Schnee ME, Ricci AJ. Calcium-induced calcium release supports recruitment of synaptic vesicles in auditory hair cells. J Neurophysiol 2015; 115:226-39. [PMID: 26510758 DOI: 10.1152/jn.00559.2015] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2015] [Accepted: 10/23/2015] [Indexed: 01/31/2023] Open
Abstract
Hair cells from auditory and vestibular systems transmit continuous sound and balance information to the central nervous system through the release of synaptic vesicles at ribbon synapses. The high activity experienced by hair cells requires a unique mechanism to sustain recruitment and replenishment of synaptic vesicles for continuous release. Using pre- and postsynaptic electrophysiological recordings, we explored the potential contribution of calcium-induced calcium release (CICR) in modulating the recruitment of vesicles to auditory hair cell ribbon synapses. Pharmacological manipulation of CICR with agents targeting endoplasmic reticulum calcium stores reduced both spontaneous postsynaptic multiunit activity and the frequency of excitatory postsynaptic currents (EPSCs). Pharmacological treatments had no effect on hair cell resting potential or activation curves for calcium and potassium channels. However, these drugs exerted a reduction in vesicle release measured by dual-sine capacitance methods. In addition, calcium substitution by barium reduced release efficacy by delaying release onset and diminishing vesicle recruitment. Together these results demonstrate a role for calcium stores in hair cell ribbon synaptic transmission and suggest a novel contribution of CICR in hair cell vesicle recruitment. We hypothesize that calcium entry via calcium channels is tightly regulated to control timing of vesicle fusion at the synapse, whereas CICR is used to maintain a tonic calcium signal to modulate vesicle trafficking.
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Affiliation(s)
- Manuel Castellano-Muñoz
- Department of Otolaryngology, Stanford University School of Medicine, Stanford, California; and
| | - Michael E Schnee
- Department of Otolaryngology, Stanford University School of Medicine, Stanford, California; and
| | - Anthony J Ricci
- Department of Otolaryngology, Stanford University School of Medicine, Stanford, California; and Department of Molecular and Cellular Physiology, Stanford University School of Medicine, Stanford, California
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Majewski L, Kuznicki J. SOCE in neurons: Signaling or just refilling? BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2015; 1853:1940-52. [DOI: 10.1016/j.bbamcr.2015.01.019] [Citation(s) in RCA: 72] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/02/2014] [Revised: 01/22/2015] [Accepted: 01/26/2015] [Indexed: 01/14/2023]
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Abstract
Endoplasmic reticulum (ER) stress is an intricate mechanism that mediates numerous responses during brain ischemia, thus being essential to determine the fate of neurons. In recent years, studies of the mechanisms of brain ischemic injury have centered on ER stress, glutamate excitotoxicity, dysfunction of mitochondria, inflammatory reactions, calcium overload and death receptor pathways. The role of ER stress is highly important. In addition to resulting in neuronal cell death through calcium toxicity and apoptotic pathways, ER stress also triggers a series of adaptive responses including unfolded protein response (UPR), autophagy, the expression of pro-survival proteins and the enhancement of ER self-repair ability, leading to less ischemic brain damage. This paper provides an overview of recent advances in understanding of the relations between ER stress and brain ischemia.
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Affiliation(s)
- Yingchao Su
- a Department of Neurology, the Second Affiliated Hospital of Harbin Medical University , Harbin 150086 , China
| | - Feng Li
- a Department of Neurology, the Second Affiliated Hospital of Harbin Medical University , Harbin 150086 , China
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43
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Disrupted-in-schizophrenia 1 regulates transport of ITPR1 mRNA for synaptic plasticity. Nat Neurosci 2015; 18:698-707. [DOI: 10.1038/nn.3984] [Citation(s) in RCA: 49] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2014] [Accepted: 02/22/2015] [Indexed: 02/07/2023]
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44
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King AN, Manning CF, Trimmer JS. A unique ion channel clustering domain on the axon initial segment of mammalian neurons. J Comp Neurol 2015; 522:2594-608. [PMID: 24477962 DOI: 10.1002/cne.23551] [Citation(s) in RCA: 60] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2013] [Revised: 01/21/2014] [Accepted: 01/22/2014] [Indexed: 01/11/2023]
Abstract
The axon initial segment (AIS) plays a key role in initiation of action potentials and neuronal output. The plasma membrane of the AIS contains high densities of voltage-gated ion channels required for these electrical events, and much recent work has focused on defining the mechanisms for generating and maintaining this unique neuronal plasma membrane domain. The Kv2.1 voltage-gated potassium channel is abundantly present in large clusters on the soma and proximal dendrites of mammalian brain neurons. Kv2.1 is also a component of the ion channel repertoire at the AIS. Here we show that Kv2.1 clusters on the AIS of brain neurons across diverse mammalian species including humans define a noncanonical ion channel clustering domain deficient in Ankyrin-G. The sites of Kv2.1 clustering on the AIS are sites where cisternal organelles, specialized intracellular calcium release membranes, come into close apposition with the plasma membrane, and are also sites of clustering of γ-aminobutyric acid (GABA)ergic synapses. Using an antibody specific for a single Kv2.1 phosphorylation site, we find that the phosphorylation state differs between Kv2.1 clusters on the proximal and distal portions of the AIS. Together, these studies show that the sites of Kv2.1 clustering on the AIS represent specialized domains containing components of diverse neuronal signaling pathways that may contribute to local regulation of Kv2.1 function and AIS membrane excitability.
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Affiliation(s)
- Anna N King
- Department of Neurobiology, Physiology and Behavior, University of California, Davis, California, 95616
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Adasme T, Paula-Lima A, Hidalgo C. Inhibitory ryanodine prevents ryanodine receptor-mediated Ca²⁺ release without affecting endoplasmic reticulum Ca²⁺ content in primary hippocampal neurons. Biochem Biophys Res Commun 2015; 458:57-62. [PMID: 25623539 DOI: 10.1016/j.bbrc.2015.01.065] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2015] [Accepted: 01/15/2015] [Indexed: 10/24/2022]
Abstract
Ryanodine is a cell permeant plant alkaloid that binds selectively and with high affinity to ryanodine receptor (RyR) Ca(2+) release channels. Sub-micromolar ryanodine concentrations activate RyR channels while micromolar concentrations are inhibitory. Several reports indicate that neuronal synaptic plasticity, learning and memory require RyR-mediated Ca(2+)-release, which is essential for muscle contraction. The use of micromolar (inhibitory) ryanodine represents a common strategy to suppress RyR activity in neuronal cells: however, micromolar ryanodine promotes RyR-mediated Ca(2+) release and endoplasmic reticulum Ca(2+) depletion in muscle cells. Information is lacking in this regard in neuronal cells; hence, we examined here if addition of inhibitory ryanodine elicited Ca(2+) release in primary hippocampal neurons, and if prolonged incubation of primary hippocampal cultures with inhibitory ryanodine affected neuronal ER calcium content. Our results indicate that inhibitory ryanodine does not cause Ca(2+) release from the ER in primary hippocampal neurons, even though ryanodine diffusion should produce initially low intracellular concentrations, within the RyR activation range. Moreover, neurons treated for 1 h with inhibitory ryanodine had comparable Ca(2+) levels as control neurons. These combined findings imply that prolonged incubation with inhibitory ryanodine, which effectively abolishes RyR-mediated Ca(2+) release, preserves ER Ca(2+) levels and thus constitutes a sound strategy to suppress neuronal RyR function.
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Affiliation(s)
- Tatiana Adasme
- Biomedical Neuroscience Institute and Centro de Estudios Moleculares de la Célula, Faculty of Medicine, Universidad de Chile, Santiago, Chile
| | - Andrea Paula-Lima
- Biomedical Neuroscience Institute and Centro de Estudios Moleculares de la Célula, Faculty of Medicine, Universidad de Chile, Santiago, Chile; Institute for Research in Dental Sciences, Faculty of Dentistry, Universidad de Chile, Santiago, Chile
| | - Cecilia Hidalgo
- Biomedical Neuroscience Institute and Centro de Estudios Moleculares de la Célula, Faculty of Medicine, Universidad de Chile, Santiago, Chile; Programa de Fisiología y Biofísica, Instituto de Ciencias Biomédicas, Facultad de Medicina, Universidad de Chile, Chile.
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Garcia-Alvarez G, Lu B, Yap KAF, Wong LC, Thevathasan JV, Lim L, Ji F, Tan KW, Mancuso JJ, Tang W, Poon SY, Augustine GJ, Fivaz M. STIM2 regulates PKA-dependent phosphorylation and trafficking of AMPARs. Mol Biol Cell 2015; 26:1141-59. [PMID: 25609091 PMCID: PMC4357513 DOI: 10.1091/mbc.e14-07-1222] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
STIMs (STIM1 and STIM2 in mammals) are transmembrane proteins that reside in the endoplasmic reticulum and regulate store-operated Ca2+ entry. STIM2 mediates cAMP/PKA-dependent phosphorylation of the AMPA receptor subunit GluA1 in excitatory neurons. In addition, STIM2 promotes cAMP-dependent surface delivery of GluA1. STIMs (STIM1 and STIM2 in mammals) are transmembrane proteins that reside in the endoplasmic reticulum (ER) and regulate store-operated Ca2+ entry (SOCE). The function of STIMs in the brain is only beginning to be explored, and the relevance of SOCE in nerve cells is being debated. Here we identify STIM2 as a central organizer of excitatory synapses. STIM2, but not its paralogue STIM1, influences the formation of dendritic spines and shapes basal synaptic transmission in excitatory neurons. We further demonstrate that STIM2 is essential for cAMP/PKA-dependent phosphorylation of the AMPA receptor (AMPAR) subunit GluA1. cAMP triggers rapid migration of STIM2 to ER–plasma membrane (PM) contact sites, enhances recruitment of GluA1 to these ER-PM junctions, and promotes localization of STIM2 in dendritic spines. Both biochemical and imaging data suggest that STIM2 regulates GluA1 phosphorylation by coupling PKA to the AMPAR in a SOCE-independent manner. Consistent with a central role of STIM2 in regulating AMPAR phosphorylation, STIM2 promotes cAMP-dependent surface delivery of GluA1 through combined effects on exocytosis and endocytosis. Collectively our results point to a unique mechanism of synaptic plasticity driven by dynamic assembly of a STIM2 signaling complex at ER-PM contact sites.
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Affiliation(s)
- Gisela Garcia-Alvarez
- Program in Neuroscience and Behavioral Disorders, DUKE-NUS Graduate Medical School, Singapore 169857
| | - Bo Lu
- Program in Neuroscience and Behavioral Disorders, DUKE-NUS Graduate Medical School, Singapore 169857
| | - Kenrick An Fu Yap
- Program in Neuroscience and Behavioral Disorders, DUKE-NUS Graduate Medical School, Singapore 169857
| | - Loo Chin Wong
- Program in Neuroscience and Behavioral Disorders, DUKE-NUS Graduate Medical School, Singapore 169857
| | - Jervis Vermal Thevathasan
- Program in Neuroscience and Behavioral Disorders, DUKE-NUS Graduate Medical School, Singapore 169857
| | - Lynette Lim
- Program in Neuroscience and Behavioral Disorders, DUKE-NUS Graduate Medical School, Singapore 169857
| | - Fang Ji
- Program in Neuroscience and Behavioral Disorders, DUKE-NUS Graduate Medical School, Singapore 169857
| | - Kia Wee Tan
- Program in Neuroscience and Behavioral Disorders, DUKE-NUS Graduate Medical School, Singapore 169857
| | - James J Mancuso
- Program in Neuroscience and Behavioral Disorders, DUKE-NUS Graduate Medical School, Singapore 169857
| | - Willcyn Tang
- Program in Neuroscience and Behavioral Disorders, DUKE-NUS Graduate Medical School, Singapore 169857
| | - Shou Yu Poon
- Program in Neuroscience and Behavioral Disorders, DUKE-NUS Graduate Medical School, Singapore 169857
| | - George J Augustine
- Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore 637553 Center for Functional Connectomics, Korea Institute of Science and Technology, Seoul 136-791, Republic of Korea
| | - Marc Fivaz
- Program in Neuroscience and Behavioral Disorders, DUKE-NUS Graduate Medical School, Singapore 169857 Department of Physiology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore 117597
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General anesthetic isoflurane modulates inositol 1,4,5-trisphosphate receptor calcium channel opening. Anesthesiology 2014; 121:528-37. [PMID: 24878495 DOI: 10.1097/aln.0000000000000316] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
BACKGROUND Pharmacological evidence suggests that inhalational general anesthetics induce neurodegeneration in vitro and in vivo through overactivation of inositol trisphosphate receptor (InsP3R) Ca-release channels, but it is not clear whether these effects are due to direct modulation of channel activity by the anesthetics. METHODS Using single-channel patch clamp electrophysiology, the authors examined the gating of rat recombinant type 3 InsP3R (InsP3R-3) Ca-release channels in isolated nuclei (N = 3 to 15) from chicken lymphocytes modulated by isoflurane at clinically relevant concentrations in the absence and presence of physiological levels of the agonist inositol 1,4,5-trisphosphate (InsP3). The authors also examined the effects of isoflurane on InsP3R-mediated Ca release from the endoplasmic reticulum and changes in intracellular Ca concentration ([Ca]i). RESULTS Clinically relevant concentrations (approximately 1 minimal alveolar concentration) of the commonly used general anesthetic, isoflurane, activated InsP3R-3 channels with open probability similar to channels activated by 1 µM InsP3 (Po ≈ 0.2). This isoflurane modulation of InsP3R-3 Po depended biphasically on [Ca]i. Combination of isoflurane with subsaturating levels of InsP3 in patch pipettes resulted in at least two-fold augmentations of InsP3R-3 channel Po compared with InsP3 alone. These effects were not noted in the presence of saturating [InsP3]. Application of isoflurane to DT40 cells resulted in a 30% amplification of InsP3R-mediated [Ca]i oscillations, whereas InsP3-induced increase in [Ca]i and cleaved caspase-3 activity were enhanced by approximately 2.5-fold. CONCLUSION These results suggest that the InsP3R may be a direct molecular target of isoflurane and plays a role in the mechanisms of anesthetic-mediated pharmacological or neurotoxic effects.
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Iwashita M. Phasic activation of ventral tegmental neurons increases response and pattern similarity in prefrontal cortex neurons. eLife 2014; 3. [PMID: 25269147 PMCID: PMC4206826 DOI: 10.7554/elife.02726] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2014] [Accepted: 09/28/2014] [Indexed: 12/15/2022] Open
Abstract
Dopamine is critical for higher neural processes and modifying the activity of the prefrontal cortex (PFC). However, the mechanism of dopamine contribution to the modification of neural representation is unclear. Using in vivo two-photon population Ca2+ imaging in awake mice, this study investigated how neural representation of visual input to PFC neurons is regulated by dopamine. Phasic stimulation of dopaminergic neurons in the ventral tegmental area (VTA) evoked prolonged Ca2+ transients, lasting ∼30 s in layer 2/3 neurons of the PFC, which are regulated by a dopamine D1 receptor-dependent pathway. Furthermore, only a conditioning protocol with visual sensory input applied 0.5 s before the VTA dopaminergic input could evoke enhanced Ca2+ transients and increased pattern similarity (or establish a neural representation) of PFC neurons to the same sensory input. By increasing both the level of neuronal response and pattern similarity, dopaminergic input may establish robust and reliable cortical representation. DOI:http://dx.doi.org/10.7554/eLife.02726.001 Around 120 years ago, Ivan Pavlov unintentionally sparked a new field of psychology research. He did so by noting that his dogs had learned to associate the sound of the bell that he rang before feeding them with the food itself, such that they would salivate upon hearing the bell even when there was no food present. This form of learning—now known as associative learning—has since been demonstrated in species from honeybees to humans. For the brain to associate two events, such as the sound of a bell and the delivery of food, it must encode the first event and keep that information available or ‘on-line’ until the occurrence of the second event, at which point the two can be linked together. This process takes place in part of the brain called the prefrontal cortex, but the mechanism by which it occurs is largely unclear. Now, Iwashita has obtained new insights into the molecular basis of associative learning by studying how the activity of the prefrontal cortex is affected by the activity of a second region of the brain. This second region, called the ventral tegmental area, is part of the brain's reward circuit: it becomes active whenever an animal experiences a desirable event, such as receiving food, and supplies a neurotransmitter called dopamine to its target areas, which include the prefrontal cortex. Electrodes were used to mimic the changes in brain activity that occur when a mouse learns to associate a visual stimulus with a reward: this involved repeatedly activating the visual cortex in a conscious mouse, followed by activation of the ventral tegmental area. Short-lived increases in calcium levels were seen in the prefrontal cortex, raising the possibility that these ‘calcium transients’ are the signal that enables the brain to link two events. Moreover, blocking proteins called dopamine D1 receptors in the prefrontal cortex reduced the calcium transients, which is consistent with existing evidence that dopamine from the ventral tegmental area is required for associative learning. Intriguingly, the calcium transients lasted for roughly 30 s, which is also the maximum length of time by which a stimulus and a reward can be separated and still be associated. Given that the calcium transients could not be detected in anesthetized mice, a full understanding of the mechanisms underlying associative learning may require studies of the conscious brain. DOI:http://dx.doi.org/10.7554/eLife.02726.002
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Affiliation(s)
- Motoko Iwashita
- 1National Institute of Mental Health, National Institutes of Health, Bethesda, United States
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Artemisia santolinifolia enhances glutamatergic neurotransmission in the nucleus of the solitary tract. Neurosci Lett 2014; 582:115-9. [PMID: 25220699 DOI: 10.1016/j.neulet.2014.08.048] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2014] [Revised: 08/27/2014] [Accepted: 08/28/2014] [Indexed: 12/25/2022]
Abstract
Artemisia extracts have been used as remedies for a variety of maladies related to metabolic and gastrointestinal control. Because the vagal afferent-nucleus of the solitary tract (NST) synapse regulates the same homeostatic functions affected by Artemisia, it is possible that these extracts may have activity at the synaptic level in the NST. Therefore, we evaluated how extracts of three common medicinal Artemisia species, Artemisia santolinifolia (SANT), Artemisia scoparia (SCO), and Artemisia dracunculus L (PMI-5011), modulate the excitability of the glutamatergic vagal afferent-NST synapse. Our in vitro live cell calcium imaging data from prelabeled vagal afferent terminals show that SANT extract is a positive modulator of vagal afferent calcium levels, as the extract significantly increased the calcium signal relative to the time control. Neither SCO nor PMI-5011 extract altered the vagal calcium signals compared to the time control. Furthermore, whole cell voltage-clamp recordings from NST neurons corroborated the vagal terminal calcium data in that SANT extract also significantly increased miniature excitatory postsynaptic current (mEPSC) frequency in NST neurons. These data suggest that SANT extract could be a pharmacologically significant mediator of glutamatergic neurotransmission within the CNS.
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Paula-Lima AC, Adasme T, Hidalgo C. Contribution of Ca2+ release channels to hippocampal synaptic plasticity and spatial memory: potential redox modulation. Antioxid Redox Signal 2014; 21:892-914. [PMID: 24410659 DOI: 10.1089/ars.2013.5796] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
SIGNIFICANCE Memory is an essential human cognitive function. Consequently, to unravel the cellular and molecular mechanisms responsible for the synaptic plasticity events underlying memory formation, storage and loss represents a major challenge of present-day neuroscience. RECENT ADVANCES This review article first describes the wide-ranging functions played by intracellular Ca2+ signals in the activity-dependent synaptic plasticity processes underlying hippocampal spatial memory, and next, it focuses on how the endoplasmic reticulum Ca2+ release channels, the ryanodine receptors, and the inositol 1,4,5-trisphosphate receptors contribute to these processes. We present a detailed examination of recent evidence supporting the key role played by Ca2+ release channels in synaptic plasticity, including structural plasticity, and the formation/consolidation of spatial memory in the hippocampus. CRITICAL ISSUES Changes in cellular oxidative state particularly affect the function of Ca2+ release channels and alter hippocampal synaptic plasticity and the associated memory processes. Emphasis is placed in this review on how defective Ca2+ release, presumably due to increased levels of reactive oxygen species, may cause the hippocampal functional defects that are associated to aging and Alzheimer's disease (AD). FUTURE DIRECTIONS Additional studies should examine the precise molecular mechanisms by which Ca2+ release channels contribute to hippocampal synaptic plasticity and spatial memory formation/consolidation. Future studies should test whether redox-modified Ca2+ release channels contribute toward generating the intracellular Ca2+ signals required for sustained synaptic plasticity and hippocampal spatial memory, and whether loss of redox balance and oxidative stress, by altering Ca2+ release channel function, presumably contribute to the abnormal memory processes that occur during aging and AD.
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Affiliation(s)
- Andrea C Paula-Lima
- 1 Faculty of Dentistry, Institute for Research in Dental Sciences, Universidad de Chile , Santiago, Chile
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