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The zinc paradigm for metalloneurochemistry. Essays Biochem 2017; 61:225-235. [DOI: 10.1042/ebc20160073] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2016] [Revised: 03/10/2017] [Accepted: 03/28/2017] [Indexed: 01/06/2023]
Abstract
Neurotransmission and sensory perception are shaped through metal ion–protein interactions in various brain regions. The term "metalloneurochemistry" defines the unique field of bioinorganic chemistry focusing on these processes, and zinc has been the leading target of metalloneurochemists in the almost 15 years since the definition was introduced. Zinc in the hippocampus interacts with receptors that dictate ion flow and neurotransmitter release. Understanding the intricacies of these interactions is crucial to uncovering the role that zinc plays in learning and memory. Based on receptor similarities and zinc-enriched neurons (ZENs) in areas of the brain responsible for sensory perception, such as the olfactory bulb (OB), and dorsal cochlear nucleus (DCN), zinc participates in odor and sound perception. Development and improvement of methods which allow for precise detection and immediate manipulation of zinc ions in neuronal cells and in brain slices will be critical in uncovering the synaptic action of zinc and, more broadly, the bioinorganic chemistry of cognition.
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Sunuwar L, Asraf H, Donowitz M, Sekler I, Hershfinkel M. The Zn 2+-sensing receptor, ZnR/GPR39, upregulates colonocytic Cl - absorption, via basolateral KCC1, and reduces fluid loss. Biochim Biophys Acta Mol Basis Dis 2017; 1863:947-960. [PMID: 28093242 PMCID: PMC5557417 DOI: 10.1016/j.bbadis.2017.01.009] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2016] [Revised: 01/10/2017] [Accepted: 01/12/2017] [Indexed: 12/13/2022]
Abstract
Administration of zinc, as a complement to oral rehydration solutions, effectively diminishes duration and severity of diarrhea, but it is not known whether it merely fulfills a nutritional deficiency, or if zinc has a direct role of regulating solute absorption. We show that Zn2+ acts via a specific receptor, ZnR/GPR39, to reduce fluid loss. Intestinal fluid secretion triggered by cholera toxin (CTx) was lower in WT mice compared to ZnR/GPR39 KO. In the absence of dietary Zn2+ we observed similar fluid accumulation in WT and ZnR/GPR39 KO mice, indicating that Zn2+ and ZnR/GPR39 are both required for a beneficial effect of Zn2+ in diarrhea. In primary colonocytes and in Caco-2 colonocytic cells, activation of ZnR/GPR39 enhanced Cl- transport, a critical factor in diarrhea, by upregulating K+/Cl- cotransporter (KCC1) activity. Importantly, we show basolateral expression of KCC1 in mouse and human colonocytes, thus identifying a novel Cl- absorption pathway. Finally, inhibition of KCC-dependent Cl- transport enhanced CTx-induced fluid loss. Altogether, our data indicate that Zn2+ acting via ZnR/GPR39 has a direct role in controlling Cl- absorption via upregulation of basolateral KCC1 in the colon. Moreover, colonocytic ZnR/GPR39 and KCC1 reduce water loss during diarrhea and may therefore serve as effective drug targets.
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Affiliation(s)
- Laxmi Sunuwar
- Department of Physiology and Cell Biology, Faculty of Health Sciences, Ben-Gurion University of the Negev, Beer Sheva, Israel
| | - Hila Asraf
- Department of Physiology and Cell Biology, Faculty of Health Sciences, Ben-Gurion University of the Negev, Beer Sheva, Israel
| | - Mark Donowitz
- Department of Medicine, Division of Gastroenterology, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Israel Sekler
- Department of Physiology and Cell Biology, Faculty of Health Sciences, Ben-Gurion University of the Negev, Beer Sheva, Israel
| | - Michal Hershfinkel
- Department of Physiology and Cell Biology, Faculty of Health Sciences, Ben-Gurion University of the Negev, Beer Sheva, Israel.
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53
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Khan MZ, He L. Neuro-psychopharmacological perspective of Orphan receptors of Rhodopsin (class A) family of G protein-coupled receptors. Psychopharmacology (Berl) 2017; 234:1181-1207. [PMID: 28289782 DOI: 10.1007/s00213-017-4586-9] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/28/2016] [Accepted: 02/27/2017] [Indexed: 12/28/2022]
Abstract
BACKGROUND In the central nervous system (CNS), G protein-coupled receptors (GPCRs) are the most fruitful targets for neuropsychopharmacological drug development. Rhodopsin (class A) is the most studied class of GPCR and includes orphan receptors for which the endogenous ligand is not known or is unclear. Characterization of orphan GPCRs has proven to be challenging, and the production pace of GPCR-based drugs has been incredibly slow. OBJECTIVE Determination of the functions of these receptors may provide unexpected insight into physiological and neuropathological processes. Advances in various methods and techniques to investigate orphan receptors including in situ hybridization and knockdown/knockout (KD/KO) showed extensive expression of these receptors in the mammalian brain and unmasked their physiological and neuropathological roles. Due to these rapid progress and development, orphan GPCRs are rising as a new and promising class of drug targets for neurodegenerative diseases and psychiatric disorders. CONCLUSION This review presents a neuropsychopharmacological perspective of 26 orphan receptors of rhodopsin (class A) family, namely GPR3, GPR6, GPR12, GPR17, GPR26, GPR35, GPR39, GPR48, GPR49, GPR50, GPR52, GPR55, GPR61, GPR62, GPR63, GPR68, GPR75, GPR78, GPR83, GPR84, GPR85, GPR88, GPR153, GPR162, GPR171, and TAAR6. We discussed the expression of these receptors in mammalian brain and their physiological roles. Furthermore, we have briefly highlighted their roles in neurodegenerative diseases and psychiatric disorders including Alzheimer's disease, Parkinson's disease, neuroinflammation, inflammatory pain, bipolar and schizophrenic disorders, epilepsy, anxiety, and depression.
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Affiliation(s)
- Muhammad Zahid Khan
- Department of Pharmacology, China Pharmaceutical University, No. 24 Tong Jia Xiang, Nanjing, Jiangsu Province, 210009, China.
| | - Ling He
- Department of Pharmacology, China Pharmaceutical University, No. 24 Tong Jia Xiang, Nanjing, Jiangsu Province, 210009, China
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54
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Sela H, Cohen H, Karpas Z, Zeiri Y. Distinctive hippocampal zinc distribution patterns following stress exposure in an animal model of PTSD. Metallomics 2017; 9:323-333. [PMID: 28252129 DOI: 10.1039/c6mt00207b] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Emerging evidence suggests that zinc (Zn) deficiency is associated with depression and anxiety in both human and animal studies. The present study sought to assess whether there is an association between the magnitude of behavioral responses to stress and patterns of Zn distribution. The work has focused on one case study, the association between an animal model of posttraumatic stress disorder (PTSD) and the Zn distribution in the rat hippocampus. Behaviors were assessed with the elevated plus-maze and acoustic startle response tests 7 days later. Preset cut-off criteria classified exposed animals according to their individual behavioral responses. To further characterize the distribution of Zn that occurs in the hippocampus 8 days after the exposure, laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS) imaging was used. It has been found that Zn distribution in the dentate gyrus (DG) sub-region in the hippocampus is clearly more widely spread for rats that belong to the extreme behavioral response (EBR) group as compared to the control group. Comparison of the Zn concentration changes in the cornu ammonis 1 (CA1) and the DG sub-regions of the hippocampus shows that the concentration changes are statistically significantly higher in the EBR rats compared to the rats in the control and minimal behavioral response (MBR) groups. In order to understand the mechanism of stress-induced hippocampal Zn dyshomeostasis, relative quantitative analyses of metallothionein (MT), B-cell lymphoma 2 (Bcl-2) and caspase 3 immunoreactivity were performed. Significant differences in the number of caspase-ir and Bcl-2 cells were found in the hippocampal DG sub-region between the EBR group and the control and MBR groups. The results of this study demonstrate a statistically significant association between the degree of behavioral disruption resulting from stress exposure and the patterns of Zn distribution and concentration changes in the various hippocampal regions. Taken together, these findings indicate that Zn distribution patterns play an active role in the neurobiological response to predator scent stress.
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Affiliation(s)
- Hagit Sela
- Biomedical Engineering, Ben-Gurion University of the Negev, Beer-Sheva 8410501, Israel. and Department of Chemistry, NRCN, P.O. Box 9001, Beer-Sheva 8419001, Israel.
| | - Hagit Cohen
- Beer-Sheva Mental Health Center, The State of Israel Ministry of Health, Anxiety and Stress Research Unit, Faculty of Health Sciences, Ben-Gurion University of the Negev, Beer-Sheva, Israel.
| | - Zeev Karpas
- Department of Chemistry, NRCN, P.O. Box 9001, Beer-Sheva 8419001, Israel.
| | - Yehuda Zeiri
- Biomedical Engineering, Ben-Gurion University of the Negev, Beer-Sheva 8410501, Israel. and Department of Chemistry, NRCN, P.O. Box 9001, Beer-Sheva 8419001, Israel.
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55
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Notartomaso S, Mascio G, Scarselli P, Martinello K, Fucile S, Gradini R, Bruno V, Battaglia G, Nicoletti F. Expression of the K +/Cl - cotransporter, KCC2, in cerebellar Purkinje cells is regulated by group-I metabotropic glutamate receptors. Neuropharmacology 2017; 115:51-59. [PMID: 27498071 DOI: 10.1016/j.neuropharm.2016.07.032] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2016] [Revised: 06/30/2016] [Accepted: 07/26/2016] [Indexed: 10/21/2022]
Abstract
The neuronal K+/Cl- symporter, KCC2, shapes synaptic responses mediated by Cl--permeant GABAA receptors. Moving from the evidence that excitatory neurotransmission drives changes in KCC2 expression in cerebellar neurons, we studied the regulation of KCC2 expression by group-I metabotropic glutamate (mGlu) receptors in the cerebellum of adult mice. Mice lacking mGlu5 receptors showed a large reduction in cerebellar KCC2 protein levels and a loss of KCC2 immunoreactivity in Purkinje cells. Similar changes were seen in mice treated with the mGlu5 receptor antagonist, MPEP, whereas treatment with the mGlu5 receptor positive allosteric modulator (PAM), VU0360172, increased KCC2 expression. In contrast, pharmacological inhibition of mGlu1 receptors with JNJ16259685 enhanced cerebellar KCC2 protein levels and KCC2 immunoreactivity in Purkinje cells, whereas treatment with the mGlu1 receptor PAM, RO0711401, reduced KCC2 expression. To examine whether the reduction in KCC2 expression caused by the absence or the inhibition of mGlu5 receptors could affect GABAergic transmission, we performed electrophysiological and behavioral studies. Recording of extracellular action potentials in Purkinje cells showed that the inhibitory effect of the GABAA receptor agonist, muscimol, was lost in cerebellar slices prepared from mGlu5-/- mice or from mice treated systemically with MPEP, in line with the reduction in KCC2 expression. Similarly, motor impairment caused by the GABAA receptor PAM, diazepam, was attenuated in mice pre-treated with MPEP. These findings disclose a novel function of mGlu5 receptors in the cerebellum and suggest that mGlu5 receptor ligands might influence GABAergic transmission in the cerebellum and affect motor responses to GABA-mimetic drugs. This article is part of the Special Issue entitled 'Metabotropic Glutamate Receptors, 5 years on'.
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Affiliation(s)
| | | | | | | | - Sergio Fucile
- IRCCS Neuromed, Pozzilli, Italy; Department of Physiology and Pharmacology, University Sapienza of Rome, Italy
| | - Roberto Gradini
- IRCCS Neuromed, Pozzilli, Italy; Department of Experimental Medicine, University Sapienza of Rome, Italy
| | - Valeria Bruno
- IRCCS Neuromed, Pozzilli, Italy; Department of Physiology and Pharmacology, University Sapienza of Rome, Italy
| | | | - Ferdinando Nicoletti
- IRCCS Neuromed, Pozzilli, Italy; Department of Physiology and Pharmacology, University Sapienza of Rome, Italy.
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56
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Kitayama T, Morita K, Motoyama N, Dohi T. Down-regulation of zinc transporter-1 in astrocytes induces neuropathic pain via the brain-derived neurotrophic factor - K +-Cl - co-transporter-2 signaling pathway in the mouse spinal cord. Neurochem Int 2016; 101:120-131. [PMID: 27818163 DOI: 10.1016/j.neuint.2016.11.001] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2016] [Revised: 11/02/2016] [Accepted: 11/02/2016] [Indexed: 10/20/2022]
Abstract
We previously demonstrated, using a DNA microarray analysis, the down-regulated expression of the slc30a1 gene (zinc transporter 1, ZnT1) in a neuropathic pain model induced by partial sciatic nerve ligation (PSNL). Zinc is an essential trace mineral that plays important roles in physiological functions, and ZnT1 modulates intracellular zinc levels. In the present study, we examined the effects of the down-regulation of the ZnT1 gene in the spinal cord on tactile allodynia. The knockdown (KD) of ZnT1 by the intrathecal administration of siRNA against ZnT1 to mice induced allodynia, a characteristic syndrome of neuropathic pain, which persisted for at least one month. ZnT1 KD increased intracellular zinc concentrations in primary astrocyte cultures, and this was followed by enhanced PKCα membrane translocation and NFκB nuclear translocation as well as increases in the levels of IL-6 and BDNF expressed and the phosphorylation of CREB in vitro. Neuropathic pain induced by ZnT1 KD was inhibited by an IL-6, BDNF, and TrkB siRNA injection. The down-regulated expression of KCC2 in spinal cord was induced by ZnT1 KD and prevented by an intrathecal injection of IL-6, BDNF, and TrkB siRNA. These results indicate that PSNL via the down-regulated expression of ZnT1 increases intracellular zinc concentrations, enhances PKCα membrane translocation and NFκB nuclear translocation, up-regulates the expression of IL-6, increases the phosphorylation of CREB, and promotes the BDNF cascade reaction in astrocytes, thereby down-regulating the expression of KCC2 and inducing neuropathic pain in vivo. This mechanism is considered to be responsible for the activation of TrkB in neurons through the release of BDNF from astrocytes. The results of the present study also indicate that zinc signaling in astrocytes occurs upstream of the BDNF-TrkB-KCC2 cascade reaction.
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Affiliation(s)
- Tomoya Kitayama
- Department of Pharmacy, School of Pharmacy and Pharmaceutical Science, Mukogawa Women's University, Hyogo 663-8179, Japan.
| | - Katsuya Morita
- Department of Pharmacology, Faculty of Nursing, Hiroshima Bunka Gakuen University, 2-10-3 Agaminami, Kure-city, Hiroshima 737-0004, Japan.
| | - Naoyo Motoyama
- Department of Dental Science for Health Promotion, Division of Integrated Health Sciences, Institute of Biomedical & Health Sciences, Hiroshima University, 1-2-3 Kasumi, Minami-ku, Hiroshima 734-8553, Japan.
| | - Toshihiro Dohi
- Department of Pharmacology, Faculty of Nursing, Hiroshima Bunka Gakuen University, 2-10-3 Agaminami, Kure-city, Hiroshima 737-0004, Japan.
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57
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Młyniec K, Gaweł M, Doboszewska U, Starowicz G, Nowak G. The Role of Elements in Anxiety. VITAMINS AND HORMONES 2016; 103:295-326. [PMID: 28061974 DOI: 10.1016/bs.vh.2016.09.002] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Elements (bioelements) are necessary factors required for the physiological function of organisms. They are critically involved in fundamental processes of life. Extra- and intracellular message and metabolic pathway factors as well as structural components include one or many elements in their functional structure. Recent years have seen an intensification in terms of knowledge gained about the roles of elements in anxiety disorders. In this chapter we present a review of the most important current data concerning the involvement of zinc, magnesium, copper, lithium, iron, and manganese, and their deficiency, in the pathophysiology and treatment of anxiety.
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Affiliation(s)
- K Młyniec
- Faculty of Pharmacy, Jagiellonian University Medical College, Krakow, Poland.
| | - M Gaweł
- Faculty of Pharmacy, Jagiellonian University Medical College, Krakow, Poland
| | - U Doboszewska
- Faculty of Pharmacy, Jagiellonian University Medical College, Krakow, Poland
| | - G Starowicz
- Faculty of Pharmacy, Jagiellonian University Medical College, Krakow, Poland
| | - G Nowak
- Faculty of Pharmacy, Jagiellonian University Medical College, Krakow, Poland
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58
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Qiao J, Zhao H, Zhang Y, Peng H, Chen Q, Zhang H, Zheng X, Jin Y, Ni H, Duan E, Guo Y. GPR39 is region-specifically expressed in mouse oviduct correlating with the Zn 2+ distribution. Theriogenology 2016; 88:98-105. [PMID: 27865419 DOI: 10.1016/j.theriogenology.2016.09.040] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2014] [Revised: 09/19/2016] [Accepted: 09/23/2016] [Indexed: 01/05/2023]
Abstract
G-protein-coupled receptor 39 (GPR39) plays a role in cellular and physiological processes, including insulin secretion, cell death inhibition, wound healing, and obesity. Increasing evidence suggests that GPR39 is potently stimulated by zinc ions (Zn2+) and is therefore considered a putative Zn2+ receptor. Given the importance of Zn2+ in the reproductive system, we proposed that GPR39 might have a functional role in the reproductive system. However, the localization of GPR39 in the reproductive system remains unknown. Here, we used mice expressing a Gpr39 promoter-driven LacZ reporter system to detect Gpr39 expression in the reproductive system at different phases of the estrous cycle and found an interesting region-specific distribution of Gpr39 in the mouse oviduct epithelium, with strong expression at the ampulla and weak expression at the isthmus, which was consistent with the results using reverse transcription polymerase chain reaction and immunofluorescence. Moreover, using ZnSeAMG staining, we found that Zn2+, the putative ligand of GPR39, also found a distribution similar to GPR39 expression, suggesting that their potential interaction mediates fertilization and embryo transportation.
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Affiliation(s)
- Jingqiao Qiao
- College of Animal Science and Technology, Beijing University of Agriculture, Beijing, China
| | - Huashan Zhao
- State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing, China
| | - Ying Zhang
- State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing, China
| | - Hongying Peng
- State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing, China
| | - Qi Chen
- State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing, China
| | - He Zhang
- College of Veterinary Medicine, Northwest A&F University, Yangling, Shaanxi, China
| | - Xueying Zheng
- College of Animal Science and Technology, Beijing University of Agriculture, Beijing, China
| | - Yaping Jin
- College of Veterinary Medicine, Northwest A&F University, Yangling, Shaanxi, China
| | - Hemin Ni
- College of Animal Science and Technology, Beijing University of Agriculture, Beijing, China
| | - Enkui Duan
- State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing, China.
| | - Yong Guo
- College of Animal Science and Technology, Beijing University of Agriculture, Beijing, China.
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59
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Abramovitch-Dahan C, Asraf H, Bogdanovic M, Sekler I, Bush AI, Hershfinkel M. Amyloid β attenuates metabotropic zinc sensing receptor, mZnR/GPR39, dependent Ca2+
, ERK1/2 and Clusterin signaling in neurons. J Neurochem 2016; 139:221-233. [DOI: 10.1111/jnc.13760] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2016] [Revised: 08/02/2016] [Accepted: 08/03/2016] [Indexed: 12/28/2022]
Affiliation(s)
- Chen Abramovitch-Dahan
- Department of Physiology and Cell Biology; Faculty of Health Sciences; Ben-Gurion University of the Negev; Beer-Sheva Israel
| | - Hila Asraf
- Department of Physiology and Cell Biology; Faculty of Health Sciences; Ben-Gurion University of the Negev; Beer-Sheva Israel
| | - Milos Bogdanovic
- Department of Physiology and Cell Biology; Faculty of Health Sciences; Ben-Gurion University of the Negev; Beer-Sheva Israel
| | - Israel Sekler
- Department of Physiology and Cell Biology; Faculty of Health Sciences; Ben-Gurion University of the Negev; Beer-Sheva Israel
| | - Ashley I. Bush
- Florey Institute of Neuroscience and Mental Health; University of Melbourne; Parkville Victoria Australia
| | - Michal Hershfinkel
- Department of Physiology and Cell Biology; Faculty of Health Sciences; Ben-Gurion University of the Negev; Beer-Sheva Israel
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60
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Potential antidepressant-like properties of the TC G-1008, a GPR39 (zinc receptor) agonist. J Affect Disord 2016; 201:179-84. [PMID: 27235821 DOI: 10.1016/j.jad.2016.05.007] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/24/2015] [Revised: 03/26/2016] [Accepted: 05/09/2016] [Indexed: 01/20/2023]
Abstract
Some forms of depression appear to be more related to the glutamatergic system. G-coupled protein receptor 39 (GPR39) is the metabotropic zinc receptor, which may be involved in the pathophysiology of depression and in the antidepressant response. Its deficiency abolishes the antidepressant response, which means that GPR39 is required to obtain a therapeutic effect in depression. This raises the possibility that agonists of the zinc receptor may have a role in antidepressant treatment. To explore this possibility we investigated animal behaviour in the forced swim test, the tail suspension test (to assess antidepressant-like properties), the light/dark test and the elevated plus maze test (to assess anxiolytic-like properties), following acute administration of a GPR39 agonist (TC G-1008). We found an antidepressant response (as measured by the forced swim test but not by the tail suspension test) in mice following the GPR39 agonist treatment. Additionally, we observed the opposite results in the light/dark box (decreased overall distance; increased time spent in the lit compartment; decreased time spent in the dark compartment; increased freezing time) and elevated plus maze (no significant changes), which may be a consequence of the sedative effect of TC G-1008. We also found hippocampal GPR39 and brain-derived neurotrophic factor (BDNF) up-regulation following administration of the GPR39 agonist, which may be undiscovered so far as a possible novel agent in the treatment of mood disorders.
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61
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Mlyniec K. Zinc in the Glutamatergic Theory of Depression. Curr Neuropharmacol 2016; 13:505-13. [PMID: 26412070 PMCID: PMC4790399 DOI: 10.2174/1570159x13666150115220617] [Citation(s) in RCA: 43] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2014] [Revised: 12/19/2014] [Accepted: 01/07/2015] [Indexed: 11/22/2022] Open
Abstract
Depression is a serious psychiatric illness that affects millions of people worldwide. Weeks of antidepressant therapy are required to relieve depressive symptoms, and new drugs are still being extensively researched. The latest studies have shown that in depression, there is an imbalance between the main excitatory (glutamatergic) and inhibitory (GABAergic) systems. Administration of antagonists of the glutamatergic system, including zinc, has shown an antidepressant effect in preclinical as well as clinical studies. Zinc inhibits the NMDA receptor via its binding site located on one of its subunits. This is thought to be the main mechanism explaining the antidepressant properties of zinc. In the present review, a link between zinc and the glutamatergic system is discussed in the context of depressive disorder.
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Affiliation(s)
- Katarzyna Mlyniec
- Department of Biochemical Toxicology, Jagiellonian University Collegium Medicum, Medyczna 9, PL 30-688 Krakow, Poland
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62
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Wu H, Che X, Tang J, Ma F, Pan K, Zhao M, Shao A, Wu Q, Zhang J, Hong Y. The K(+)-Cl(-) Cotransporter KCC2 and Chloride Homeostasis: Potential Therapeutic Target in Acute Central Nervous System Injury. Mol Neurobiol 2016; 53:2141-51. [PMID: 25941074 DOI: 10.1007/s12035-015-9162-x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2014] [Accepted: 03/26/2015] [Indexed: 12/11/2022]
Abstract
The K(+)-Cl(-) cotransporter-2 (KCC2) is a well-known member of the electroneutral cation-chloride cotransporters with a restricted expression pattern to neurons. This transmembrane protein mediates the efflux of Cl(-) out of neurons and exerts a critical role in inhibitory γ-aminobutyric acidergic (GABAergic) and glycinergic neurotransmission. Moreover, KCC2 participates in the regulation of various physiological processes of neurons, including cell migration, dendritic outgrowth, spine morphology, and dendritic synaptogenesis. It is important to note that down-regulation of KCC2 is associated with the pathogenesis of multiple neurological diseases, which is of particular relevance to acute central nervous system (CNS) injury. In this review, we aim to survey the pathogenic significance of KCC2 down-regulation under the condition of acute CNS injuries. We propose that further elucidation of the molecular mechanisms regarding KCC2 down-regulation after acute CNS injuries is necessary because of potential promising avenues for prevention and treatment of acute CNS injury.
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Affiliation(s)
- Haijian Wu
- Department of Neurosurgery, Second Affiliated Hospital, School of Medicine, Zhejiang University, 88 Jiefang Road, Hangzhou, 310009, Zhejiang, China
| | - Xiaoru Che
- Department of Cardiology, Zhejiang Provincial People's Hospital, Hangzhou, China
| | - Junjia Tang
- Department of Neurosurgery, Second Affiliated Hospital, School of Medicine, Zhejiang University, 88 Jiefang Road, Hangzhou, 310009, Zhejiang, China
| | - Feiqiang Ma
- Department of Emergency Medicine, Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, China
| | - Kun Pan
- Department of Neurosurgery, New York-Presbyterian Hospital, New York, NY, USA
| | - Mingfei Zhao
- Department of Neurosurgery, Second Affiliated Hospital, School of Medicine, Zhejiang University, 88 Jiefang Road, Hangzhou, 310009, Zhejiang, China
| | - Anwen Shao
- Department of Neurosurgery, Second Affiliated Hospital, School of Medicine, Zhejiang University, 88 Jiefang Road, Hangzhou, 310009, Zhejiang, China
| | - Qun Wu
- Department of Neurosurgery, Second Affiliated Hospital, School of Medicine, Zhejiang University, 88 Jiefang Road, Hangzhou, 310009, Zhejiang, China
| | - Jianmin Zhang
- Department of Neurosurgery, Second Affiliated Hospital, School of Medicine, Zhejiang University, 88 Jiefang Road, Hangzhou, 310009, Zhejiang, China
| | - Yuan Hong
- Department of Neurosurgery, Second Affiliated Hospital, School of Medicine, Zhejiang University, 88 Jiefang Road, Hangzhou, 310009, Zhejiang, China.
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63
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Mahadevan V, Woodin MA. Regulation of neuronal chloride homeostasis by neuromodulators. J Physiol 2016; 594:2593-605. [PMID: 26876607 PMCID: PMC4865579 DOI: 10.1113/jp271593] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2015] [Accepted: 01/10/2016] [Indexed: 01/23/2023] Open
Abstract
KCC2 is the central regulator of neuronal Cl(-) homeostasis, and is critical for enabling strong hyperpolarizing synaptic inhibition in the mature brain. KCC2 hypofunction results in decreased inhibition and increased network hyperexcitability that underlies numerous disease states including epilepsy, neuropathic pain and neuropsychiatric disorders. The current holy grail of KCC2 biology is to identify how we can rescue KCC2 hypofunction in order to restore physiological levels of synaptic inhibition and neuronal network activity. It is becoming increasingly clear that diverse cellular signals regulate KCC2 surface expression and function including neurotransmitters and neuromodulators. In the present review we explore the existing evidence that G-protein-coupled receptor (GPCR) signalling can regulate KCC2 activity in numerous regions of the nervous system including the hypothalamus, hippocampus and spinal cord. We present key evidence from the literature suggesting that GPCR signalling is a conserved mechanism for regulating chloride homeostasis. This evidence includes: (1) the activation of group 1 metabotropic glutamate receptors and metabotropic Zn(2+) receptors strengthens GABAergic inhibition in CA3 pyramidal neurons through a regulation of KCC2; (2) activation of the 5-hydroxytryptamine type 2A serotonin receptors upregulates KCC2 cell surface expression and function, restores endogenous inhibition in motoneurons, and reduces spasticity in rats; and (3) activation of A3A-type adenosine receptors rescues KCC2 dysfunction and reverses allodynia in a model of neuropathic pain. We propose that GPCR-signals are novel endogenous Cl(-) extrusion enhancers that may regulate KCC2 function.
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Affiliation(s)
- Vivek Mahadevan
- Department of Cell and Systems Biology, University of Toronto, Toronto, Ontario, Canada
| | - Melanie A Woodin
- Department of Cell and Systems Biology, University of Toronto, Toronto, Ontario, Canada
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Khan MZ. A possible significant role of zinc and GPR39 zinc sensing receptor in Alzheimer disease and epilepsy. Biomed Pharmacother 2016; 79:263-72. [PMID: 27044837 DOI: 10.1016/j.biopha.2016.02.026] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2016] [Revised: 02/16/2016] [Accepted: 02/16/2016] [Indexed: 12/14/2022] Open
Abstract
Zinc the essential trace element, plays a significant role in the brain development and in the proper brain functions at every stage of life. Misbalance of zinc (Zn(2+)) ions in the central nervous system is involved in the pathogenesis of numerous neurodegenerative disorders such as Alzheimer's disease, Depression, and Epilepsy. In brain, Zn(2+) has been identified as a ligand, capable of activating and inhibiting the receptors including the NMDA-type glutamate receptors (NMDARs), GABAA receptors, nicotinic acetylcholine receptors (nAChRs), glycine receptors (glyR) and serotonin receptors (5-HT3). Recently GPR39 has been identified as a zinc-specific receptor, widely expressed in brain tissues including the frontal cortex, amygdala, and hippocampus. GPR39, when binding with Zn(2+) has shown promising therapeutic potentials. This review presents current knowledge regarding the role of GPR39 zinc sensing receptor in brain, with a focus on Alzheimer's disease and Epilepsy. Although the results are encouraging, further research is needed to clarify zinc and GPR39 role in the treatment of Alzheimer's disease and Epilepsy.
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Affiliation(s)
- Muhammad Zahid Khan
- Department of Pharmacology, China Pharmaceutical University, Nanjing 210009, China.
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65
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Taylor AMW, Castonguay A, Ghogha A, Vayssiere P, Pradhan AAA, Xue L, Mehrabani S, Wu J, Levitt P, Olmstead MC, De Koninck Y, Evans CJ, Cahill CM. Neuroimmune Regulation of GABAergic Neurons Within the Ventral Tegmental Area During Withdrawal from Chronic Morphine. Neuropsychopharmacology 2016; 41:949-59. [PMID: 26202104 PMCID: PMC4748420 DOI: 10.1038/npp.2015.221] [Citation(s) in RCA: 81] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/02/2015] [Revised: 07/10/2015] [Accepted: 07/11/2015] [Indexed: 12/13/2022]
Abstract
Opioid dependence is accompanied by neuroplastic changes in reward circuitry leading to a negative affective state contributing to addictive behaviors and risk of relapse. The current study presents a neuroimmune mechanism through which chronic opioids disrupt the ventral tegmental area (VTA) dopaminergic circuitry that contributes to impaired reward behavior. Opioid dependence was induced in rodents by treatment with escalating doses of morphine. Microglial activation was observed in the VTA following spontaneous withdrawal from chronic morphine treatment. Opioid-induced microglial activation resulted in an increase in brain-derived neurotrophic factor (BDNF) expression and a reduction in the expression and function of the K(+)Cl(-) co-transporter KCC2 within VTA GABAergic neurons. Inhibition of microglial activation or interfering with BDNF signaling prevented the loss of Cl(-) extrusion capacity and restored the rewarding effects of cocaine in opioid-dependent animals. Consistent with a microglial-derived BDNF-induced disruption of reward, intra-VTA injection of BDNF or a KCC2 inhibitor resulted in a loss of cocaine-induced place preference in opioid-naïve animals. The loss of the extracellular Cl(-) gradient undermines GABAA-mediated inhibition, and represents a mechanism by which chronic opioid treatments can result in blunted reward circuitry. This study directly implicates microglial-derived BDNF as a negative regulator of reward in opioid-dependent states, identifying new therapeutic targets for opiate addictive behaviors.
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Affiliation(s)
- Anna M W Taylor
- Department of Anesthesiology and Perioperative Care, University of California, Irvine, CA, USA
- Hatos Center for Neuropharmacology, Semel Institute for Neuroscience and Human Behavior, University of California, Los Angeles, CA, USA
| | - Annie Castonguay
- Institut Universitaire en Santé Mentale de Québec, Québec, QC, Canada
- Department of Psychiatry and Neuroscience, Université Laval, Québec, QC, Canada
| | - Atefeh Ghogha
- Hatos Center for Neuropharmacology, Semel Institute for Neuroscience and Human Behavior, University of California, Los Angeles, CA, USA
| | - Pia Vayssiere
- Hatos Center for Neuropharmacology, Semel Institute for Neuroscience and Human Behavior, University of California, Los Angeles, CA, USA
| | - Amynah A A Pradhan
- Hatos Center for Neuropharmacology, Semel Institute for Neuroscience and Human Behavior, University of California, Los Angeles, CA, USA
| | - Lihua Xue
- Department of Biomedical and Molecular Sciences, Queen's University, Kingston, ON, Canada
| | - Sadaf Mehrabani
- Hatos Center for Neuropharmacology, Semel Institute for Neuroscience and Human Behavior, University of California, Los Angeles, CA, USA
| | - Juli Wu
- Children's Hospital Los Angeles and the Keck School of Medicine of the University of Southern California, Los Angeles, CA, USA
| | - Pat Levitt
- Children's Hospital Los Angeles and the Keck School of Medicine of the University of Southern California, Los Angeles, CA, USA
| | - Mary C Olmstead
- Department of Psychology, Queen's University, Kingston, ON, Canada
| | - Yves De Koninck
- Institut Universitaire en Santé Mentale de Québec, Québec, QC, Canada
- Department of Psychiatry and Neuroscience, Université Laval, Québec, QC, Canada
| | - Christopher J Evans
- Hatos Center for Neuropharmacology, Semel Institute for Neuroscience and Human Behavior, University of California, Los Angeles, CA, USA
| | - Catherine M Cahill
- Department of Anesthesiology and Perioperative Care, University of California, Irvine, CA, USA
- Department of Biomedical and Molecular Sciences, Queen's University, Kingston, ON, Canada
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Fjellström O, Larsson N, Yasuda SI, Tsuchida T, Oguma T, Marley A, Wennberg-Huldt C, Hovdal D, Fukuda H, Yoneyama Y, Sasaki K, Johansson A, Lundqvist S, Brengdahl J, Isaacs RJ, Brown D, Geschwindner S, Benthem L, Priest C, Turnbull A. Novel Zn2+ Modulated GPR39 Receptor Agonists Do Not Drive Acute Insulin Secretion in Rodents. PLoS One 2015; 10:e0145849. [PMID: 26720709 PMCID: PMC4697807 DOI: 10.1371/journal.pone.0145849] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2015] [Accepted: 12/09/2015] [Indexed: 12/24/2022] Open
Abstract
Type 2 diabetes (T2D) occurs when there is insufficient insulin release to control blood glucose, due to insulin resistance and impaired β-cell function. The GPR39 receptor is expressed in metabolic tissues including pancreatic β-cells and has been proposed as a T2D target. Specifically, GPR39 agonists might improve β-cell function leading to more adequate and sustained insulin release and glucose control. The present study aimed to test the hypothesis that GPR39 agonism would improve glucose stimulated insulin secretion in vivo. A high throughput screen, followed by a medicinal chemistry program, identified three novel potent Zn2+ modulated GPR39 agonists. These agonists were evaluated in acute rodent glucose tolerance tests. The results showed a lack of glucose lowering and insulinotropic effects not only in lean mice, but also in diet-induced obese (DIO) mice and Zucker fatty rats. It is concluded that Zn2+ modulated GPR39 agonists do not acutely stimulate insulin release in rodents.
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Affiliation(s)
- Ola Fjellström
- Medicinal Chemistry CVMD iMed, AstraZeneca R&D Gothenburg, Mölndal, Sweden
- * E-mail:
| | - Niklas Larsson
- Discovery Sciences, AstraZeneca R&D Gothenburg, Mölndal, Sweden
| | - Shin-ichiro Yasuda
- Pharmacology Research Laboratories II, Mitsubishi Tanabe Pharma Corporation, Kawagishi, Toda-shi, Saitama, Japan
| | - Takuma Tsuchida
- Pharmacology Research Laboratories II, Mitsubishi Tanabe Pharma Corporation, Kawagishi, Toda-shi, Saitama, Japan
| | - Takahiro Oguma
- Pharmacology Research Laboratories II, Mitsubishi Tanabe Pharma Corporation, Kawagishi, Toda-shi, Saitama, Japan
| | - Anna Marley
- Discovery Sciences, AstraZeneca R&D, Mereside, United Kingdom
| | | | - Daniel Hovdal
- DMPK CVMD iMed, AstraZeneca R&D Gothenburg, Mölndal, Sweden
| | - Hajime Fukuda
- DMPK Research Laboratories, Mitsubishi Tanabe Pharma Corporation, Kawagishi, Toda-shi, Saitama, Japan
| | - Yukimi Yoneyama
- DMPK Research Laboratories, Mitsubishi Tanabe Pharma Corporation, Kawagishi, Toda-shi, Saitama, Japan
| | - Kazuyo Sasaki
- Pharmacology Research Laboratories II, Mitsubishi Tanabe Pharma Corporation, Kawagishi, Toda-shi, Saitama, Japan
| | - Anders Johansson
- Medicinal Chemistry CVMD iMed, AstraZeneca R&D Gothenburg, Mölndal, Sweden
| | - Sara Lundqvist
- Discovery Sciences, AstraZeneca R&D Gothenburg, Mölndal, Sweden
| | - Johan Brengdahl
- Discovery Sciences, AstraZeneca R&D Gothenburg, Mölndal, Sweden
| | - Richard J. Isaacs
- Molecular Sensing, Inc., Nashville, Tennessee, United States of America
| | - Daniel Brown
- Molecular Sensing, Inc., Nashville, Tennessee, United States of America
| | | | | | - Claire Priest
- Discovery Sciences, AstraZeneca R&D, Mereside, United Kingdom
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Kang SK, Johnston MV, Kadam SD. Acute TrkB inhibition rescues phenobarbital-resistant seizures in a mouse model of neonatal ischemia. Eur J Neurosci 2015; 42:2792-804. [PMID: 26452067 PMCID: PMC4715496 DOI: 10.1111/ejn.13094] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2015] [Revised: 09/17/2015] [Accepted: 09/29/2015] [Indexed: 02/04/2023]
Abstract
Neonatal seizures are commonly associated with hypoxic-ischemic encephalopathy. Phenobarbital (PB) resistance is common and poses a serious challenge in clinical management. Using a newly characterized neonatal mouse model of ischemic seizures, this study investigated a novel strategy for rescuing PB resistance. A small-molecule TrkB antagonist, ANA12, used to selectively and transiently block post-ischemic BDNF-TrkB signaling in vivo, determined whether rescuing TrkB-mediated post-ischemic degradation of the K(+)-Cl(-) co-transporter (KCC2) rescued PB-resistant seizures. The anti-seizure efficacy of ANA12 + PB was quantified by (i) electrographic seizure burden using acute continuous video-electroencephalograms and (ii) post-treatment expression levels of KCC2 and NKCC1 using Western blot analysis in postnatal day (P)7 and P10 CD1 pups with unilateral carotid ligation. ANA12 significantly rescued PB-resistant seizures at P7 and improved PB efficacy at P10. A single dose of ANA12 + PB prevented the post-ischemic degradation of KCC2 for up to 24 h. As anticipated, ANA12 by itself had no anti-seizure properties and was unable to prevent KCC2 degradation at 24 h without follow-on PB. This indicates that unsubdued seizures can independently lead to KCC2 degradation via non-TrkB-dependent pathways. This study, for the first time as a proof-of-concept, reports the potential therapeutic value of KCC2 modulation for the management of PB-resistant seizures in neonates. Future investigations are required to establish the mechanistic link between ANA12 and the prevention of KCC2 degradation.
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Affiliation(s)
- S K Kang
- Neuroscience Laboratory, Hugo Moser Research Institute at Kennedy Krieger, 716 North Broadway, Baltimore, MD, 21205, USA
| | - M V Johnston
- Neuroscience Laboratory, Hugo Moser Research Institute at Kennedy Krieger, 716 North Broadway, Baltimore, MD, 21205, USA
- Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD, 21205, USA
- Department of Pediatrics, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - S D Kadam
- Neuroscience Laboratory, Hugo Moser Research Institute at Kennedy Krieger, 716 North Broadway, Baltimore, MD, 21205, USA
- Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD, 21205, USA
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68
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Ganay T, Asraf H, Aizenman E, Bogdanovic M, Sekler I, Hershfinkel M. Regulation of neuronal pH by the metabotropic Zn(2+)-sensing Gq-coupled receptor, mZnR/GPR39. J Neurochem 2015; 135:897-907. [PMID: 26375174 DOI: 10.1111/jnc.13367] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2015] [Revised: 09/01/2015] [Accepted: 09/08/2015] [Indexed: 11/29/2022]
Abstract
Synaptically released Zn(2+) acts as a neurotransmitter, in part, by activating the postsynaptic metabotropic Zn(2+)-sensing Gq protein-coupled receptor (mZnR/GPR39). In previous work using epithelial cells, we described crosstalk between Zn(2+) signaling and changes in intracellular pH and/or extracellular pH (pHe). As pH changes accompany neuronal activity under physiological and pathological conditions, we tested whether Zn(2+) signaling is involved in regulation of neuronal pH. Here, we report that up-regulation of a major H(+) extrusion pathway, the Na(+)/H(+) exchanger (NHE), is induced by mZnR/GPR39 activation in an extracellular-regulated kinase 1/2-dependent manner in hippocampal neurons in vitro. We also observed that changes in pHe can modulate neuronal mZnR/GPR39-dependent signaling, resulting in reduced activity at pHe 8 or 6.5. Similarly, Zn(2+)-dependent extracellular-regulated kinase 1/2 phosphorylation and up-regulation of NHE activity were absent at acidic pHe. Thus, our results suggest that when pHe is maintained within the physiological range, mZnR/GPR39 activation can up-regulate NHE-dependent recovery from intracellular acidification. During acidosis, as pHe drops, mZnR/GPR39-dependent NHE activation is inhibited, thereby attenuating further H(+) extrusion. This mechanism may serve to protect neurons from excessive decreases in pHe. Thus, mZnR/GPR39 signaling provides a homeostatic adaptive process for regulation of intracellular and extracellular pH changes in the brain. We show that the postsynaptic metabotropic Zn(2+)-sensing Gq protein-coupled receptor (mZnR/GPR39) activation induces up-regulation of a major neuronal H(+) extrusion pathway, the Na(+)/H(+) exchanger (NHE), thereby enhancing neuronal recovery from intracellular acidification. Changes in extracellular pH (pHe), however, modulate neuronal mZnR/GPR39-dependent signaling, resulting in reduced activity at pHe 8 or 6.5. This mechanism may serve to protect neurons from excessive decreases in pHe during acidosis. Hence, mZnR/GPR39 signaling provides a homeostatic adaptive process for regulation of intracellular and extracellular pH changes in the brain.
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Affiliation(s)
- Thibault Ganay
- Department of Physiology and Cell Biology and The Zlotowski Center of Neuroscience, Faculty of Health Sciences, Ben-Gurion University of the Negev, Beer-Sheva, Israel
| | - Hila Asraf
- Department of Physiology and Cell Biology and The Zlotowski Center of Neuroscience, Faculty of Health Sciences, Ben-Gurion University of the Negev, Beer-Sheva, Israel
| | - Elias Aizenman
- Department of Physiology and Cell Biology and The Zlotowski Center of Neuroscience, Faculty of Health Sciences, Ben-Gurion University of the Negev, Beer-Sheva, Israel.,Department of Neurobiology and Pittsburgh Institute for Neurodegenerative Diseases, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
| | - Milos Bogdanovic
- Department of Physiology and Cell Biology and The Zlotowski Center of Neuroscience, Faculty of Health Sciences, Ben-Gurion University of the Negev, Beer-Sheva, Israel
| | - Israel Sekler
- Department of Physiology and Cell Biology and The Zlotowski Center of Neuroscience, Faculty of Health Sciences, Ben-Gurion University of the Negev, Beer-Sheva, Israel
| | - Michal Hershfinkel
- Department of Physiology and Cell Biology and The Zlotowski Center of Neuroscience, Faculty of Health Sciences, Ben-Gurion University of the Negev, Beer-Sheva, Israel
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69
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Watanabe M, Fukuda A. Development and regulation of chloride homeostasis in the central nervous system. Front Cell Neurosci 2015; 9:371. [PMID: 26441542 PMCID: PMC4585146 DOI: 10.3389/fncel.2015.00371] [Citation(s) in RCA: 136] [Impact Index Per Article: 15.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2015] [Accepted: 09/04/2015] [Indexed: 12/22/2022] Open
Abstract
γ-Aminobutyric acid (GABA) is the main inhibitory neurotransmitter of the mature central nervous system (CNS). The developmental switch of GABAergic transmission from excitation to inhibition is induced by changes in Cl− gradients, which are generated by cation-Cl− co-transporters. An accumulation of Cl− by the Na+-K+-2Cl− co-transporter (NKCC1) increases the intracellular Cl− concentration ([Cl−]i) such that GABA depolarizes neuronal precursors and immature neurons. The subsequent ontogenetic switch, i.e., upregulation of the Cl−-extruder KCC2, which is a neuron-specific K+-Cl− co-transporter, with or without downregulation of NKCC1, results in low [Cl−]i levels and the hyperpolarizing action of GABA in mature neurons. Development of Cl− homeostasis depends on developmental changes in NKCC1 and KCC2 expression. Generally, developmental shifts (decreases) in [Cl−]i parallel the maturation of the nervous system, e.g., early in the spinal cord, hypothalamus and thalamus, followed by the limbic system, and last in the neocortex. There are several regulators of KCC2 and/or NKCC1 expression, including brain-derived neurotrophic factor (BDNF), insulin-like growth factor (IGF), and cystic fibrosis transmembrane conductance regulator (CFTR). Therefore, regionally different expression of these regulators may also contribute to the regional developmental shifts of Cl− homeostasis. KCC2 and NKCC1 functions are also regulated by phosphorylation by enzymes such as PKC, Src-family tyrosine kinases, and WNK1–4 and their downstream effectors STE20/SPS1-related proline/alanine-rich kinase (SPAK)-oxidative stress responsive kinase-1 (OSR1). In addition, activation of these kinases is modulated by humoral factors such as estrogen and taurine. Because these transporters use the electrochemical driving force of Na+ and K+ ions, topographical interaction with the Na+-K+ ATPase and its modulators such as creatine kinase (CK) should modulate functions of Cl− transporters. Therefore, regional developmental regulation of these regulators and modulators of Cl− transporters may also play a pivotal role in the development of Cl− homeostasis.
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Affiliation(s)
- Miho Watanabe
- Department of Neurophysiology, Hamamatsu University School of Medicine Hamamatsu, Japan
| | - Atsuo Fukuda
- Department of Neurophysiology, Hamamatsu University School of Medicine Hamamatsu, Japan
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Gilad D, Shorer S, Ketzef M, Friedman A, Sekler I, Aizenman E, Hershfinkel M. Homeostatic regulation of KCC2 activity by the zinc receptor mZnR/GPR39 during seizures. Neurobiol Dis 2015; 81:4-13. [PMID: 25562657 PMCID: PMC4490144 DOI: 10.1016/j.nbd.2014.12.020] [Citation(s) in RCA: 55] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2014] [Revised: 12/11/2014] [Accepted: 12/23/2014] [Indexed: 12/31/2022] Open
Abstract
The aim of this study was to investigate the role of the synaptic metabotropic zinc receptor mZnR/GPR39 in physiological adaptation to epileptic seizures. We previously demonstrated that synaptic activation of mZnR/GPR39 enhances inhibitory drive in the hippocampus by upregulating neuronal K(+)/Cl(-) co-transporter 2 (KCC2) activity. Here, we first show that mZnR/GPR39 knockout (KO) adult mice have dramatically enhanced susceptibility to seizures triggered by a single intraperitoneal injection of kainic acid, when compared to wild type (WT) littermates. Kainate also substantially enhances seizure-associated gamma oscillatory activity in juvenile mZnR/GPR39 KO hippocampal slices, a phenomenon that can be reproduced in WT tissue by extracellular Zn(2+) chelation. Importantly, kainate-induced synaptic Zn(2+) release enhances surface expression and transport activity of KCC2 in WT, but not mZnR/GPR39 KO hippocampal neurons. Kainate-dependent upregulation of KCC2 requires mZnR/GPR39 activation of the Gαq/phospholipase C/extracellular regulated kinase (ERK1/2) signaling cascade. We suggest that mZnR/GPR39-dependent upregulation of KCC2 activity provides homeostatic adaptation to an excitotoxic stimulus by increasing inhibition. As such, mZnR/GPR39 may provide a novel pharmacological target for dampening epileptic seizure activity.
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Affiliation(s)
- David Gilad
- Department of Physiology and Cell Biology, Ben-Gurion University of the Negev, Faculty of Health Sciences, Beer-Sheva, Israel
| | - Sharon Shorer
- Department of Physiology and Cell Biology, Ben-Gurion University of the Negev, Faculty of Health Sciences, Beer-Sheva, Israel
| | - Maya Ketzef
- Department of Physiology and Cell Biology, Ben-Gurion University of the Negev, Faculty of Health Sciences, Beer-Sheva, Israel
| | - Alon Friedman
- Department of Physiology and Cell Biology, Ben-Gurion University of the Negev, Faculty of Health Sciences, Beer-Sheva, Israel
| | - Israel Sekler
- Department of Physiology and Cell Biology, Ben-Gurion University of the Negev, Faculty of Health Sciences, Beer-Sheva, Israel
| | - Elias Aizenman
- Department of Physiology and Cell Biology, Ben-Gurion University of the Negev, Faculty of Health Sciences, Beer-Sheva, Israel; Department of Neurobiology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Michal Hershfinkel
- Department of Physiology and Cell Biology, Ben-Gurion University of the Negev, Faculty of Health Sciences, Beer-Sheva, Israel.
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Abstract
Chronic pain attenuates midbrain dopamine (DA) transmission, as evidenced by a decrease in opioid-evoked DA release in the ventral striatum, suggesting that the occurrence of chronic pain impairs reward-related behaviors. However, mechanisms by which pain modifies DA transmission remain elusive. Using in vivo microdialysis and microinjection of drugs into the mesolimbic DA system, we demonstrate in mice and rats that microglial activation in the VTA compromises not only opioid-evoked release of DA, but also other DA-stimulating drugs, such as cocaine. Our data show that loss of stimulated extracellular DA is due to impaired chloride homeostasis in midbrain GABAergic interneurons. Treatment with minocycline or interfering with BDNF signaling restored chloride transport within these neurons and recovered DA-dependent reward behavior. Our findings demonstrate that a peripheral nerve injury causes activated microglia within reward circuitry that result in disruption of dopaminergic signaling and reward behavior. These results have broad implications that are not restricted to the problem of pain, but are also relevant to affective disorders associated with disruption of reward circuitry. Because chronic pain causes glial activation in areas of the CNS important for mood and affect, our findings may translate to other disorders, including anxiety and depression, that demonstrate high comorbidity with chronic pain.
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72
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Anderson CT, Radford RJ, Zastrow ML, Zhang DY, Apfel UP, Lippard SJ, Tzounopoulos T. Modulation of extrasynaptic NMDA receptors by synaptic and tonic zinc. Proc Natl Acad Sci U S A 2015; 112:E2705-14. [PMID: 25947151 PMCID: PMC4443361 DOI: 10.1073/pnas.1503348112] [Citation(s) in RCA: 89] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Many excitatory synapses contain high levels of mobile zinc within glutamatergic vesicles. Although synaptic zinc and glutamate are coreleased, it is controversial whether zinc diffuses away from the release site or whether it remains bound to presynaptic membranes or proteins after its release. To study zinc transmission and quantify zinc levels, we required a high-affinity rapid zinc chelator as well as an extracellular ratiometric fluorescent zinc sensor. We demonstrate that tricine, considered a preferred chelator for studying the role of synaptic zinc, is unable to efficiently prevent zinc from binding low-nanomolar zinc-binding sites, such as the high-affinity zinc-binding site found in NMDA receptors (NMDARs). Here, we used ZX1, which has a 1 nM zinc dissociation constant and second-order rate constant for binding zinc that is 200-fold higher than those for tricine and CaEDTA. We find that synaptic zinc is phasically released during action potentials. In response to short trains of presynaptic stimulation, synaptic zinc diffuses beyond the synaptic cleft where it inhibits extrasynaptic NMDARs. During higher rates of presynaptic stimulation, released glutamate activates additional extrasynaptic NMDARs that are not reached by synaptically released zinc, but which are inhibited by ambient, tonic levels of nonsynaptic zinc. By performing a ratiometric evaluation of extracellular zinc levels in the dorsal cochlear nucleus, we determined the tonic zinc levels to be low nanomolar. These results demonstrate a physiological role for endogenous synaptic as well as tonic zinc in inhibiting extrasynaptic NMDARs and thereby fine tuning neuronal excitability and signaling.
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Affiliation(s)
- Charles T Anderson
- Departments of Otolaryngology and Neurobiology, University of Pittsburgh, Pittsburgh, PA 15261
| | - Robert J Radford
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, MA 02139; and
| | - Melissa L Zastrow
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, MA 02139; and
| | - Daniel Y Zhang
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, MA 02139; and
| | - Ulf-Peter Apfel
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, MA 02139; and
| | - Stephen J Lippard
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, MA 02139; and
| | - Thanos Tzounopoulos
- Departments of Otolaryngology and Neurobiology, University of Pittsburgh, Pittsburgh, PA 15261; Whitman Center, Marine Biological Laboratory, Woods Hole, MA 02543
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73
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Młyniec K, Gaweł M, Librowski T, Reczyński W, Bystrowska B, Holst B. Investigation of the GPR39 zinc receptor following inhibition of monoaminergic neurotransmission and potentialization of glutamatergic neurotransmission. Brain Res Bull 2015; 115:23-9. [PMID: 25917396 DOI: 10.1016/j.brainresbull.2015.04.005] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2014] [Revised: 03/04/2015] [Accepted: 04/15/2015] [Indexed: 01/23/2023]
Abstract
Zinc can regulate neural function in the brain via the GPR39 receptor. In the present study we investigated whether inhibition of serotonin, noradrenaline and dopamine synthesis and potentialization of glutamate, via administration of p-chlorophenylalanine (pCPA), α-methyl-p-tyrosine (αMT) and N-methyl-D-aspartatic acid (NMDA), respectively, would cause changes in GPR39 levels. Western blot analysis showed GPR39 up-regulation following 3-day administration of αMT and NMDA in the frontal cortex, and GPR39 down-regulation following 10-day administration of pCPA, αMT, and NMDA in the hippocampus of CD-1 mice. There were no changes in serum zinc levels. Additionally, we investigated tryptophan, tyrosine and glutamate concentrations in the hippocampus and frontal cortex of GPR39 knockout (GPR39 KO) mice. Liquid chromatography-mass spectrometry (LC-MS) showed a significant decrease in tryptophan and tyrosine, but not in glutamate concentrations in the hippocampus of GPR39 KO mice. There were no changes in the frontal cortex between GPR39 KO and wild type. These results indicate a possible role of the GPR39 receptor in monoaminergic and glutamatergic neurotransmission, which plays an important role in the pathophysiology of depression.
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Affiliation(s)
- Katarzyna Młyniec
- Department of Pharmacobiology, Jagiellonian University Medical College, Medyczna 9, PL 30-688 Kraków, Poland.
| | - Magdalena Gaweł
- Department of Radioligands, Jagiellonian University Medical College, Medyczna 9, PL 30-688 Kraków, Poland
| | - Tadeusz Librowski
- Department of Radioligands, Jagiellonian University Medical College, Medyczna 9, PL 30-688 Kraków, Poland
| | - Witold Reczyński
- Faculty of Material Science and Ceramics, AGH University of Science and Technology, Mickiewicza 30, PL 30-059 Kraków, Poland
| | - Beata Bystrowska
- Department Toxicology, Jagiellonian University Medical College, Medyczna 9, PL 30-688 Kraków, Poland
| | - Birgitte Holst
- Department of Neuroscience and Pharmacology University of Copenhagen, Blegdamsvej 3, DK-2200, Copenhagen, Denmark
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Up-regulation of the GPR39 Zn2+-sensing receptor and CREB/BDNF/TrkB pathway after chronic but not acute antidepressant treatment in the frontal cortex of zinc-deficient mice. Pharmacol Rep 2015; 67:1135-40. [PMID: 26481532 DOI: 10.1016/j.pharep.2015.04.003] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2014] [Revised: 03/12/2015] [Accepted: 04/07/2015] [Indexed: 11/21/2022]
Abstract
BACKGROUND The GPR39-Zn(2+)-sensing receptor seems to be involved in the pathophysiology of depression. GPR39 knockout animals show depressive- and anxiety-like behavior. Chronic treatment with selective antidepressants (ADs) up-regulates GPR39. OBJECTIVE AND METHODS In the present study we investigated whether acute or chronic treatment with imipramine, escitalopram, reboxetine and bupropion would cause changes in CREB, BDNF, TrkB and GPR39-Zn(2+) receptor proteins (measured by Western Blot) in the frontal cortex of mice fed with a low-zinc diet. RESULTS The administration of acute antidepressants induced diverse effects in the proteins that were examined (namely, GPR39 down-regulation and a reduction in CREB protein after administration of all ADs; a decrease in BDNF after administration of imipramine and escitalopram; an increase in BDNF after administration of reboxetine; no change in BDNF following administration of bupropion; and a decrease in TrkB following the administration of all ADs except bupropion). On the other hand, chronic treatment (which is required for depression relief) with all antidepressants increased the levels of all these proteins. CONCLUSIONS The present study for the first time demonstrates the up-regulation of GPR39 (and CREB, BDNF, and TrkB) protein when induced by chronic treatment with antidepressants (with different pharmacological profiles) in a zinc-deficiency model in mice. These data further indicate that the GPR39 receptor may be an important target in the antidepressant response.
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75
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Ford A, Castonguay A, Cottet M, Little JW, Chen Z, Symons-Liguori AM, Doyle T, Egan TM, Vanderah TW, De Koninck Y, Tosh DK, Jacobson KA, Salvemini D. Engagement of the GABA to KCC2 signaling pathway contributes to the analgesic effects of A3AR agonists in neuropathic pain. J Neurosci 2015; 35:6057-67. [PMID: 25878279 PMCID: PMC4397603 DOI: 10.1523/jneurosci.4495-14.2015] [Citation(s) in RCA: 60] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2014] [Revised: 02/27/2015] [Accepted: 03/05/2015] [Indexed: 01/18/2023] Open
Abstract
More than 1.5 billion people worldwide suffer from chronic pain, yet current treatment strategies often lack efficacy or have deleterious side effects in patients. Adenosine is an inhibitory neuromodulator that was previously thought to mediate antinociception through the A1 and A2A receptor subtypes. We have since demonstrated that A3AR agonists have potent analgesic actions in preclinical rodent models of neuropathic pain and that A3AR analgesia is independent of adenosine A1 or A2A unwanted effects. Herein, we explored the contribution of the GABA inhibitory system to A3AR-mediated analgesia using well-characterized mouse and rat models of chronic constriction injury (CCI)-induced neuropathic pain. The deregulation of GABA signaling in pathophysiological pain states is well established: GABA signaling can be hampered by a reduction in extracellular GABA synthesis by GAD65 and enhanced extracellular GABA reuptake via the GABA transporter, GAT-1. In neuropathic pain, GABAAR-mediated signaling can be further disrupted by the loss of the KCC2 chloride anion gradient. Here, we demonstrate that A3AR agonists (IB-MECA and MRS5698) reverse neuropathic pain via a spinal mechanism of action that modulates GABA activity. Spinal administration of the GABAA antagonist, bicuculline, disrupted A3AR-mediated analgesia. Furthermore, A3AR-mediated analgesia was associated with reductions in CCI-related GAD65 and GAT-1 serine dephosphorylation as well as an enhancement of KCC2 serine phosphorylation and activity. Our results suggest that A3AR-mediated reversal of neuropathic pain increases modulation of GABA inhibitory neurotransmission both directly and indirectly through protection of KCC2 function, underscoring the unique utility of A3AR agonists in chronic pain.
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Affiliation(s)
- Amanda Ford
- Department of Pharmacological and Physiological Science, St. Louis University School of Medicine, St. Louis, Missouri 63104
| | - Annie Castonguay
- Institut Universitaire en Santé Mentale de Québec, Québec City, Quebec G1J 2G3, Canada, Department of Psychiatry & Neuroscience, Université Laval, Québec City, Quebec G1K 7P4, Canada
| | - Martin Cottet
- Institut Universitaire en Santé Mentale de Québec, Québec City, Quebec G1J 2G3, Canada, Department of Psychiatry & Neuroscience, Université Laval, Québec City, Quebec G1K 7P4, Canada
| | - Joshua W Little
- Department of Surgery, Center for Anatomical Science and Education, St. Louis University School of Medicine, St. Louis, Missouri 63104
| | - Zhoumou Chen
- Department of Pharmacological and Physiological Science, St. Louis University School of Medicine, St. Louis, Missouri 63104
| | - Ashley M Symons-Liguori
- Department of Pharmacology, College of Medicine, University of Arizona, Tucson, Arizona 85724-5050, and
| | - Timothy Doyle
- Department of Pharmacological and Physiological Science, St. Louis University School of Medicine, St. Louis, Missouri 63104
| | - Terrance M Egan
- Department of Pharmacological and Physiological Science, St. Louis University School of Medicine, St. Louis, Missouri 63104
| | - Todd W Vanderah
- Department of Pharmacology, College of Medicine, University of Arizona, Tucson, Arizona 85724-5050, and
| | - Yves De Koninck
- Institut Universitaire en Santé Mentale de Québec, Québec City, Quebec G1J 2G3, Canada, Department of Psychiatry & Neuroscience, Université Laval, Québec City, Quebec G1K 7P4, Canada
| | - Dilip K Tosh
- Molecular Recognition Section, Laboratory of Bioorganic Chemistry, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland 20892-0810
| | - Kenneth A Jacobson
- Molecular Recognition Section, Laboratory of Bioorganic Chemistry, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland 20892-0810
| | - Daniela Salvemini
- Department of Pharmacological and Physiological Science, St. Louis University School of Medicine, St. Louis, Missouri 63104,
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76
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Gackière F, Vinay L. Contribution of the potassium-chloride cotransporter KCC2 to the strength of inhibition in the neonatal rodent spinal cord in vitro. J Neurosci 2015; 35:5307-16. [PMID: 25834055 PMCID: PMC6705413 DOI: 10.1523/jneurosci.1674-14.2015] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2014] [Revised: 02/16/2015] [Accepted: 02/26/2015] [Indexed: 11/21/2022] Open
Abstract
In healthy mature motoneurons (MNs), KCC2 cotransporters maintain the intracellular chloride concentration at low levels, a prerequisite for postsynaptic inhibition mediated by GABA and glycine. KCC2 expression in lumbar MNs is reduced after spinal cord injury (SCI) resulting in a depolarizing shift of the chloride equilibrium potential. Despite modeling studies indicating that such a downregulation of KCC2 function would reduce the strength of postsynaptic inhibition, physiological evidence is still lacking. The present study aimed at investigating the functional impact of a modification of KCC2 function. We focused on a well characterized disynaptic inhibitory pathway responsible for reciprocal inhibition between antagonistic muscles. We performed in vitro extracellular recordings on spinal cords isolated from rodents at the end of the first postnatal week. Genetic reduction of KCC2 expression, pharmacological blockade of KCC2, as well as SCI-induced downregulation of KCC2 all resulted in a reduction of the strength of reciprocal inhibition. We then tried to restore endogenous inhibition after SCI by means of zinc ions that have been shown to boost KCC2 function in other models. Zinc chloride indeed hyperpolarized the chloride equilibrium potential in MNs and increased reciprocal inhibition after neonatal SCI. This study demonstrates that the level of KCC2 function sets the strength of postsynaptic inhibition and suggests that the downregulation of KCC2 after SCI likely contributes to the high occurrence of flexor-extensor cocontractions in SCI patients.
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Affiliation(s)
- Florian Gackière
- Institut de Neurosciences de la Timone, UMR 7289, CNRS, Aix Marseille Université, 13385 Marseille cx 5, France
| | - Laurent Vinay
- Institut de Neurosciences de la Timone, UMR 7289, CNRS, Aix Marseille Université, 13385 Marseille cx 5, France
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77
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Blaesse P, Schmidt T. K-Cl cotransporter KCC2--a moonlighting protein in excitatory and inhibitory synapse development and function. Pflugers Arch 2015; 467:615-24. [PMID: 24909111 DOI: 10.1007/s00424-014-1547-6] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2014] [Revised: 05/23/2014] [Accepted: 05/26/2014] [Indexed: 01/28/2023]
Abstract
The K-Cl cotransporter KCC2 has two entirely independent biological actions as either an ion transporter or a structural protein orchestrating the organization of the cytoskeleton in neuronal structures. The K-Cl cotransport by KCC2 is central for hyperpolarizing inhibitory signaling, which is based on chloride currents mediated by γ-aminobutyric acid (GABA)- or glycine-gated receptor channels. In contrast, the structural role of KCC2 seems to be crucially involved in the maturation and regulation of excitatory glutamatergic synapses. This dual role at GABAergic/glycinergic and glutamatergic synapses makes KCC2 a key molecule in the regulation of inhibitory and excitatory signaling. Therefore, KCC2 is most likely involved in the synchronization of the two types of activity during network formation in the immature system and a similar synchronizing role might also be important under physiological and pathological conditions in mature neuronal networks. In this review, we explore new findings on the regulation of KCC2 by protease-mediated cleavage and on the structural role of KCC2 in spine morphogenesis and glutamate receptor clustering. We then discuss the implications of the putative interaction between the independent functions of the transporter and overlapping regulatory mechanisms in a neurophysiological context. In addition, we look at the multifunctional properties of KCC2 in the light of evolution and propose that KCC2 belongs to the group of moonlighting (multifunctional) proteins.
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Affiliation(s)
- Peter Blaesse
- Institute of Physiology I (Neurophysiology), Westfälische Wilhelms-University Münster, Robert-Koch-Strasse 27a, 48149, Münster, Germany,
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78
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Młyniec K, Gaweł M, Nowak G. Study of antidepressant drugs in GPR39 (zinc receptor⁻/⁻) knockout mice, showing no effect of conventional antidepressants, but effectiveness of NMDA antagonists. Behav Brain Res 2015; 287:135-8. [PMID: 25827929 DOI: 10.1016/j.bbr.2015.03.053] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2015] [Revised: 03/16/2015] [Accepted: 03/20/2015] [Indexed: 11/17/2022]
Abstract
The monoamine-based antidepressants that are currently used generate many side effects, and more than 30% of depressed patients do not respond to this therapy. Glutamate-based antidepressants seem to play an important role in therapy for depression, but there is still an extensive search for safe drugs. An antagonist of the glutamatergic NMDA receptor - namely, zinc - plays a part in maintaining homeostasis between glutamate and GABA via the GPR39 receptor, which has been found to be involved in the pathophysiology of depression. In this study we investigated the behavioral response resulting from chronic or acute treatment with monoamine-based antidepressants, such as imipramine, escitalopram or reboxetine, and from glutamate-based MK-801 or ketamine, as measured by the forced swim test (FST) in GPR39 knockout (GPR39 KO, -/-) mice versus wild-type (WT, +/+) controls. All the tested agents reduced the immobility time in the FST in the wild-type animals. However, only chronic or acute administration of MK-801 and ketamine (but not monoamine-based antidepressants) were active in the FST in GPR39 KO mice. Our results show for the first time that GPR39 is required for the antidepressant effect of monoamine-based antidepressants.
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Affiliation(s)
- Katarzyna Młyniec
- Department of Pharmacobiology, Jagiellonian University Medical College, Medyczna 9, PL 30-688 Kraków, Poland.
| | - Magdalena Gaweł
- Department of Pharmacobiology, Jagiellonian University Medical College, Medyczna 9, PL 30-688 Kraków, Poland
| | - Gabriel Nowak
- Department of Pharmacobiology, Jagiellonian University Medical College, Medyczna 9, PL 30-688 Kraków, Poland; Institute of Pharmacology, Polish Academy of Sciences, Smętna 12, PL 31-343 Kraków, Poland
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79
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GPR39 Zn(2+)-sensing receptor: a new target in antidepressant development? J Affect Disord 2015; 174:89-100. [PMID: 25490458 DOI: 10.1016/j.jad.2014.11.033] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/14/2014] [Revised: 11/17/2014] [Accepted: 11/18/2014] [Indexed: 11/23/2022]
Abstract
Zinc is a trace element released from glutamatergic terminals, and modulates the pre- and postsynaptic areas, giving a diverse biological response. Zinc is a natural ligand that inhibits the N-methyl-d-aspartate (NMDA) receptor and regulates the excessive release of glutamate. Moreover, zinc exhibits an antidepressant-like profile, as demonstrated in both preclinical and clinical studies. Recent reports indicate that the GPR39 Zn(2+)-sensing receptor is an important target for zinc "transmission" (its activation modulates/induces diverse biochemical pathways involved in neuroprotection). Preclinical studies provide evidence that zinc deficiency leads to depressive-like behavior related to down-regulation of the GPR39 Zn(2+)-sensing receptor. Zinc binds to the GPR39 and triggers signals, leading to CRE-dependent gene transcription, resulting in increases in proteins such as brain-derived neurotrophic factor (BDNF), that plays a pivotal role in antidepressant action. Chronic administration of many antidepressants induces GPR39 up-regulation, which suggests that the Zn(2+)-sensing receptor may be considered as a new target for drug development in the field of depression.
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80
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Prakash A, Bharti K, Majeed ABA. Zinc: indications in brain disorders. Fundam Clin Pharmacol 2015; 29:131-49. [PMID: 25659970 DOI: 10.1111/fcp.12110] [Citation(s) in RCA: 73] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2014] [Revised: 07/08/2014] [Accepted: 12/24/2014] [Indexed: 12/14/2022]
Abstract
Zinc is the authoritative metal which is present in our body, and reactive zinc metal is crucial for neuronal signaling and is largely distributed within presynaptic vesicles. Zinc also plays an important role in synaptic function. At cellular level, zinc is a modulator of synaptic activity and neuronal plasticity in both development and adulthood. Different importers and transporters are involved in zinc homeostasis. ZnT-3 is a main transporter involved in zinc homeostasis in the brain. It has been found that alterations in brain zinc status have been implicated in a wide range of neurological disorders including impaired brain development and many neurodegenerative disorders such as Alzheimer's disease, and mood disorders including depression, Parkinson's disease, Huntington's disease, amyotrophic lateral sclerosis, and prion disease. Furthermore, zinc has also been implicated in neuronal damage associated with traumatic brain injury, stroke, and seizure. Understanding the mechanisms that control brain zinc homeostasis is thus critical to the development of preventive and treatment strategies for these and other neurological disorders.
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Affiliation(s)
- Atish Prakash
- Brain Degeneration and Therapeutics Group, Brain and Neuroscience Communities of Research, Universiti Teknologi MARA (UiTM), Shah Alam, 40450, Malaysia; Department of Pharmacology, ISF college of Pharmacy, Ghal kalan, Moga, 142-001, India; Brain Research Laboratory, Faculty of Pharmacy, Campus Puncak Alam, Universiti Teknologi MARA (UiTM), Bandar Puncak Alam, 42300, Malaysia
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81
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Johanssen T, Suphantarida N, Donnelly PS, Liu XM, Petrou S, Hill AF, Barnham KJ. PBT2 inhibits glutamate-induced excitotoxicity in neurons through metal-mediated preconditioning. Neurobiol Dis 2015; 81:176-85. [PMID: 25697105 DOI: 10.1016/j.nbd.2015.02.008] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2014] [Revised: 02/04/2015] [Accepted: 02/06/2015] [Indexed: 01/07/2023] Open
Abstract
Excitotoxicity is the pathological process by which neuronal death occurs as a result of excessive stimulation of receptors at the excitatory synapse such as the NMDA receptor (NMDAR). Excitotoxicity has been implicated in the acute neurological damage from ischemia and traumatic brain injury and in the chronic neurodegeneration in Alzheimer's disease (AD) and Huntington's disease (HD). As a result NMDAR antagonists have become an attractive therapeutic strategy for the potential treatment of multiple neurodegenerative diseases. However NMDAR signaling is dichotomous in nature, with excessive increases in neuronal intracellular calcium through excessive NMDAR activity being lethal but moderate increases to intracellular calcium levels during normal synaptic function providing neuroprotection. Subsequently indiscriminant inhibition of this receptor is best avoided as was concluded from previous clinical trials of NMDAR antagonists. We show that the metal chaperone, PBT2, currently in clinical trials for HD, is able to protect against glutamate-induced excitotoxicity mediated through NMDARs. This was achieved by PBT2 inducing Zn(2+)-dependent increases in intracellular Ca(2+) levels resulting in preconditioning of neurons and inhibition of Ca(2+)-induced neurotoxic signaling cascade involving calpain-activated cleavage of calcineurin. Our study demonstrates that modulating intracellular Ca(2+) levels by a zinc ionophore is a valid therapeutic strategy to protect against the effects of excitotoxicity thought to underlie both acute and chronic neurodegenerative diseases.
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Affiliation(s)
- Timothy Johanssen
- Department of Pathology, The University of Melbourne, Parkville, Victoria 3010, Australia; The Florey Institute of Neuroscience and Mental Health, The University of Melbourne, Parkville, Victoria 3010, Australia; Bio21 Molecular Science and Biotechnology Institute, The University of Melbourne, Parkville, Victoria 3010, Australia.
| | - Nuttawat Suphantarida
- The Florey Institute of Neuroscience and Mental Health, The University of Melbourne, Parkville, Victoria 3010, Australia; Centre for Neural Engineering and Department of Electrical and Electronic Engineering, The University of Melbourne, Parkville, Victoria 3010, Australia
| | - Paul S Donnelly
- Bio21 Molecular Science and Biotechnology Institute, The University of Melbourne, Parkville, Victoria 3010, Australia; School of Chemistry, The University of Melbourne, Parkville, Victoria 3010, Australia
| | - Xiang M Liu
- The Florey Institute of Neuroscience and Mental Health, The University of Melbourne, Parkville, Victoria 3010, Australia; Bio21 Molecular Science and Biotechnology Institute, The University of Melbourne, Parkville, Victoria 3010, Australia
| | - Steven Petrou
- The Florey Institute of Neuroscience and Mental Health, The University of Melbourne, Parkville, Victoria 3010, Australia; Centre for Neural Engineering and Department of Electrical and Electronic Engineering, The University of Melbourne, Parkville, Victoria 3010, Australia
| | - Andrew F Hill
- Bio21 Molecular Science and Biotechnology Institute, The University of Melbourne, Parkville, Victoria 3010, Australia; Department of Biochemistry and Molecular Biology, The University of Melbourne, Parkville, Victoria 3010, Australia
| | - Kevin J Barnham
- The Florey Institute of Neuroscience and Mental Health, The University of Melbourne, Parkville, Victoria 3010, Australia; Bio21 Molecular Science and Biotechnology Institute, The University of Melbourne, Parkville, Victoria 3010, Australia; Department of Pharmacology and Therapeutics, The University of Melbourne, Parkville, Victoria 3010, Australia.
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82
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Młyniec K, Budziszewska B, Holst B, Ostachowicz B, Nowak G. GPR39 (zinc receptor) knockout mice exhibit depression-like behavior and CREB/BDNF down-regulation in the hippocampus. Int J Neuropsychopharmacol 2015; 18:pyu002. [PMID: 25609596 PMCID: PMC4360246 DOI: 10.1093/ijnp/pyu002] [Citation(s) in RCA: 59] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
BACKGROUND Zinc may act as a neurotransmitter in the central nervous system by activation of the GPR39 metabotropic receptors. METHODS In the present study, we investigated whether GPR39 knockout would cause depressive-like and/or anxiety-like behavior, as measured by the forced swim test, tail suspension test, and light/dark test. We also investigated whether lack of GPR39 would change levels of cAMP response element-binding protein (CREB),brain-derived neurotrophic factor (BDNF) and tropomyosin related kinase B (TrkB) protein in the hippocampus and frontal cortex of GPR39 knockout mice subjected to the forced swim test, as measured by Western-blot analysis. RESULTS In this study, GPR39 knockout mice showed an increased immobility time in both the forced swim test and tail suspension test, indicating depressive-like behavior and displayed anxiety-like phenotype. GPR39 knockout mice had lower CREB and BDNF levels in the hippocampus, but not in the frontal cortex, which indicates region specificity for the impaired CREB/BDNF pathway (which is important in antidepressant response) in the absence of GPR39. There were no changes in TrkB protein in either structure. In the present study, we also investigated activity in the hypothalamus-pituitary-adrenal axis under both zinc- and GPR39-deficient conditions. Zinc-deficient mice had higher serum corticosterone levels and lower glucocorticoid receptor levels in the hippocampus and frontal cortex. CONCLUSIONS There were no changes in the GPR39 knockout mice in comparison with the wild-type control mice, which does not support a role of GPR39 in hypothalamus-pituitary-adrenal axis regulation. The results of this study indicate the involvement of the GPR39 Zn(2+)-sensing receptor in the pathophysiology of depression with component of anxiety.
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Affiliation(s)
- Katarzyna Młyniec
- Department of Biochemical Toxicology, Jagiellonian University Medical College, Medyczna 9, PL 30-688 Kraków, Poland (Dr. K. Młyniec, Prof. B. Budziszewska); Institute of Pharmacology, Polish Academy of Sciences, Smętna 12, PL 31-343 Kraków, Poland (Profs. B. Budziszewska, G. Nowak); Department of Neuroscience and Pharmacology University of Copenhagen, Blegdamsvej 3, DK-2200, Copenhagen, Denmark (Prof. B. Holst); Faculty of Physics and Applied Computer Science, AGH University of Science and Technology, Kraków, Poland (Dr. B. Ostachowicz); Department of Pharmacobiology, Jagiellonian University Medical College, Medyczna 9, PL 30-688 Kraków, Poland (Prof. G. Nowak).
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83
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Heiliger E, Osmanagic A, Haase H, Golenhofen N, Grabrucker AM, Weth A, Baumgartner W. N-cadherin-mediated cell adhesion is regulated by extracellular Zn2+. Metallomics 2015; 7:355-62. [DOI: 10.1039/c4mt00300d] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Free extracellular zinc binds to N-cadherin and can modulate cellular adhesion in the nervous system at picomolar zinc concentrations.
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Affiliation(s)
- E. Heiliger
- Department of Cellular Neurobionics
- RWTH-Aachen University
- 52074 Aachen, Germany
| | - A. Osmanagic
- Department of Cellular Neurobionics
- RWTH-Aachen University
- 52074 Aachen, Germany
| | - H. Haase
- Institute of Immunology
- RWTH-Aachen University
- 52074 Aachen, Germany
- Department of Food Chemistry and Toxicology
- Berlin Institute of Technology
| | - N. Golenhofen
- Institute of Anatomy and Cell Biology
- Ulm University
- Ulm, Germany
| | - A. M. Grabrucker
- Institute of Anatomy and Cell Biology
- Ulm University
- Ulm, Germany
- WG Molecular Analysis of Synaptopathies
- Neurology Dept
| | - A. Weth
- Institute of Biomedical Mechatronics
- Johannes Kepler University of Linz
- Linz, Austria
| | - W. Baumgartner
- Department of Cellular Neurobionics
- RWTH-Aachen University
- 52074 Aachen, Germany
- Institute of Biomedical Mechatronics
- Johannes Kepler University of Linz
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84
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Di Angelantonio S, Murana E, Cocco S, Scala F, Bertollini C, Molinari MG, Lauro C, Bregestovski P, Limatola C, Ragozzino D. A role for intracellular zinc in glioma alteration of neuronal chloride equilibrium. Cell Death Dis 2014; 5:e1501. [PMID: 25356870 PMCID: PMC4237258 DOI: 10.1038/cddis.2014.437] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2014] [Revised: 09/04/2014] [Accepted: 09/09/2014] [Indexed: 11/16/2022]
Abstract
Glioma patients commonly suffer from epileptic seizures. However, the mechanisms of glioma-associated epilepsy are far to be completely understood. Using glioma-neurons co-cultures, we found that tumor cells are able to deeply influence neuronal chloride homeostasis, by depolarizing the reversal potential of γ-aminobutyric acid (GABA)-evoked currents (EGABA). EGABA depolarizing shift is due to zinc-dependent reduction of neuronal KCC2 activity and requires glutamate release from glioma cells. Consistently, intracellular zinc loading rapidly depolarizes EGABA in mouse hippocampal neurons, through the Src/Trk pathway and this effect is promptly reverted upon zinc chelation. This study provides a possible molecular mechanism linking glioma invasion to excitation/inhibition imbalance and epileptic seizures, through the zinc-mediated disruption of neuronal chloride homeostasis.
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Affiliation(s)
- S Di Angelantonio
- Istituto Pasteur-Fondazione Cenci Bolognetti, Department of Physiology and Pharmacology, Sapienza University of Rome, Piazzale Aldo Piazzale Aldo Moro 5, Roma 00185, Italy
- Center for Life Nano Science@Sapienza, Istituto Italiano di Tecnologia, Viale Regina Elena 291, Roma 00161, Italy
| | - E Murana
- Istituto Pasteur-Fondazione Cenci Bolognetti, Department of Physiology and Pharmacology, Sapienza University of Rome, Piazzale Aldo Piazzale Aldo Moro 5, Roma 00185, Italy
| | - S Cocco
- Istituto Pasteur-Fondazione Cenci Bolognetti, Department of Physiology and Pharmacology, Sapienza University of Rome, Piazzale Aldo Piazzale Aldo Moro 5, Roma 00185, Italy
| | - F Scala
- Istituto Pasteur-Fondazione Cenci Bolognetti, Department of Physiology and Pharmacology, Sapienza University of Rome, Piazzale Aldo Piazzale Aldo Moro 5, Roma 00185, Italy
| | - C Bertollini
- Istituto Pasteur-Fondazione Cenci Bolognetti, Department of Physiology and Pharmacology, Sapienza University of Rome, Piazzale Aldo Piazzale Aldo Moro 5, Roma 00185, Italy
| | - M G Molinari
- Istituto Pasteur-Fondazione Cenci Bolognetti, Department of Physiology and Pharmacology, Sapienza University of Rome, Piazzale Aldo Piazzale Aldo Moro 5, Roma 00185, Italy
| | - C Lauro
- Istituto Pasteur-Fondazione Cenci Bolognetti, Department of Physiology and Pharmacology, Sapienza University of Rome, Piazzale Aldo Piazzale Aldo Moro 5, Roma 00185, Italy
| | - P Bregestovski
- INSERM URM 1106, Aix-Marseille University, Brain Dynamics Institute, Marseille, France
| | - C Limatola
- Istituto Pasteur-Fondazione Cenci Bolognetti, Department of Physiology and Pharmacology, Sapienza University of Rome, Piazzale Aldo Piazzale Aldo Moro 5, Roma 00185, Italy
- IRCCS Neuromed, Via Atinese, Pozzilli, Italy
| | - D Ragozzino
- Istituto Pasteur-Fondazione Cenci Bolognetti, Department of Physiology and Pharmacology, Sapienza University of Rome, Piazzale Aldo Piazzale Aldo Moro 5, Roma 00185, Italy
- IRCCS Neuromed, Via Atinese, Pozzilli, Italy
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85
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Michailov Y, Ickowicz D, Breitbart H. Zn2+-stimulation of sperm capacitation and of the acrosome reaction is mediated by EGFR activation. Dev Biol 2014; 396:246-55. [PMID: 25446533 DOI: 10.1016/j.ydbio.2014.10.009] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2014] [Revised: 09/18/2014] [Accepted: 10/14/2014] [Indexed: 12/17/2022]
Abstract
Extracellular zinc regulates cell proliferation via the MAP1 kinase pathway in several cell types, and has been shown to act as a signaling molecule. The testis contains a relatively high concentration of Zn(2+), required in both the early and late stages of spermatogenesis. Despite the clinical significance of this ion, its role in mature sperm cells is poorly understood. In this study, we characterized the role of Zn(2+) in sperm capacitation and in the acrosome reaction. Western blot analysis revealed the presence of ZnR of the GPR39 type in sperm cells. We previously demonstrated the presence of active epidermal growth factor receptor (EGFR) in sperm, its possible transactivation by direct activation of G-protein coupled receptor (GPCR), and its involvement in sperm capacitation and in the acrosome reaction (AR). We show here that Zn(2+) activates the EGFR during sperm capacitation, which is mediated by activation of trans-membrane adenylyl cyclase (tmAC), protein kinase A (PKA), and the tyrosine kinase, Src. Moreover, the addition of Zn(2+) to capacitated sperm caused further stimulation of EGFR and phosphatydil-inositol-3-kinase (PI3K) phosphorylation, leading to the AR. The stimulation of the AR by Zn(2+) also occurred in the absence of Ca(2+) in the incubation medium, and required the tmAC, indicating that Zn(2+) activates a GPCR. The AR stimulated by Zn(2+) is mediated by GPR39 receptor, PKA, Src and the EGFR, as well as the EGFR down-stream effectors PI3K, phospholipase C (PLC) and protein kinase C (PKC). These data support a role for extracellular zinc, acting through the ZnR, in regulating multiple signaling pathways in sperm capacitation and the acrosome reaction.
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Affiliation(s)
- Yulia Michailov
- The Mina & Everard Faculty of Life Sciences, Bar-Ilan University, Ramat-Gan 5290002, Israel
| | - Debbi Ickowicz
- The Mina & Everard Faculty of Life Sciences, Bar-Ilan University, Ramat-Gan 5290002, Israel
| | - Haim Breitbart
- The Mina & Everard Faculty of Life Sciences, Bar-Ilan University, Ramat-Gan 5290002, Israel.
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86
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Marger L, Schubert C, Bertrand D. Zinc: An underappreciated modulatory factor of brain function. Biochem Pharmacol 2014; 91:426-35. [DOI: 10.1016/j.bcp.2014.08.002] [Citation(s) in RCA: 75] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2014] [Revised: 07/30/2014] [Accepted: 08/08/2014] [Indexed: 02/05/2023]
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87
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Protein kinase inhibitor β enhances the constitutive activity of G-protein-coupled zinc receptor GPR39. Biochem J 2014; 462:125-32. [PMID: 24869658 DOI: 10.1042/bj20131198] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
GPR39 is a G-protein-coupled zinc receptor that protects against diverse effectors of cell death. Its protective activity is mediated via constitutive activation of Gα13 and the RhoA pathway, leading to increased SRE (serum-response element)-dependent transcription; the zinc-dependent immediate activation of GPR39 involves Gq-mediated increases in cytosolic Ca2+ and Gs coupling leading to increased cAMP levels. We used the cytosolic and soluble C-terminus of GPR39 in a Y2H (yeast-2-hybrid) screen for interacting proteins, thus identifying PKIB (protein kinase A inhibitor β). Co-expression of GPR39 with PKIB increased the protective activity of GPR39 via the constitutive, but not the ligand-mediated, pathway. PKIB inhibits protein kinase A by direct interaction with its pseudosubstrate domain; mutation of this domain abolished the inhibitory activity of PKIB on protein kinase A activity, but had no effect on the interaction with GPR39, cell protection and induction of SRE-dependent transcription. Zinc caused dissociation of PKIB from GPR39, thereby liberating it to associate with protein kinase A and inhibit its activity, which would result in a negative-feedback loop with the ability to limit activation of the Gs pathway by zinc.
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88
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Yassin L, Radtke-Schuller S, Asraf H, Grothe B, Hershfinkel M, Forsythe ID, Kopp-Scheinpflug C. Nitric oxide signaling modulates synaptic inhibition in the superior paraolivary nucleus (SPN) via cGMP-dependent suppression of KCC2. Front Neural Circuits 2014; 8:65. [PMID: 24987336 PMCID: PMC4060731 DOI: 10.3389/fncir.2014.00065] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2014] [Accepted: 05/28/2014] [Indexed: 11/13/2022] Open
Abstract
Glycinergic inhibition plays a central role in the auditory brainstem circuitries involved in sound localization and in the encoding of temporal action potential firing patterns. Modulation of this inhibition has the potential to fine-tune information processing in these networks. Here we show that nitric oxide (NO) signaling in the auditory brainstem (where activity-dependent generation of NO is documented) modulates the strength of inhibition by changing the chloride equilibrium potential. Recent evidence demonstrates that large inhibitory postsynaptic currents (IPSCs) in neurons of the superior paraolivary nucleus (SPN) are enhanced by a very low intracellular chloride concentration, generated by the neuronal potassium chloride co-transporter (KCC2) expressed in the postsynaptic neurons. Our data show that modulation by NO caused a 15 mV depolarizing shift of the IPSC reversal potential, reducing the strength of inhibition in SPN neurons, without changing the threshold for action potential firing. Regulating inhibitory strength, through cGMP-dependent changes in the efficacy of KCC2 in the target neuron provides a postsynaptic mechanism for rapidly controlling the inhibitory drive, without altering the timing or pattern of the afferent spike train. Therefore, this NO-mediated suppression of KCC2 can modulate inhibition in one target nucleus (SPN), without influencing inhibitory strength of other target nuclei (MSO, LSO) even though they are each receiving collaterals from the same afferent nucleus (a projection from the medial nucleus of the trapezoid body, MNTB).
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Affiliation(s)
- Lina Yassin
- Division of Neurobiology, Department Biology II, Ludwig-Maximilians-University MunichPlanegg-Martinsried, Germany
| | - Susanne Radtke-Schuller
- Division of Neurobiology, Department Biology II, Ludwig-Maximilians-University MunichPlanegg-Martinsried, Germany
| | - Hila Asraf
- Department of Physiology and Cell Biology, Faculty of Health Sciences, Ben-Gurion University of the NegevBeer-Sheva, Israel
| | - Benedikt Grothe
- Division of Neurobiology, Department Biology II, Ludwig-Maximilians-University MunichPlanegg-Martinsried, Germany
| | - Michal Hershfinkel
- Department of Physiology and Cell Biology, Faculty of Health Sciences, Ben-Gurion University of the NegevBeer-Sheva, Israel
| | - Ian D. Forsythe
- Department of Cell Physiology and Pharmacology, University of LeicesterLeicester, UK
| | - Cornelia Kopp-Scheinpflug
- Division of Neurobiology, Department Biology II, Ludwig-Maximilians-University MunichPlanegg-Martinsried, Germany
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89
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McCord MC, Aizenman E. The role of intracellular zinc release in aging, oxidative stress, and Alzheimer's disease. Front Aging Neurosci 2014; 6:77. [PMID: 24860495 PMCID: PMC4028997 DOI: 10.3389/fnagi.2014.00077] [Citation(s) in RCA: 100] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2013] [Accepted: 04/02/2014] [Indexed: 01/26/2023] Open
Abstract
Brain aging is marked by structural, chemical, and genetic changes leading to cognitive decline and impaired neural functioning. Further, aging itself is also a risk factor for a number of neurodegenerative disorders, most notably Alzheimer’s disease (AD). Many of the pathological changes associated with aging and aging-related disorders have been attributed in part to increased and unregulated production of reactive oxygen species (ROS) in the brain. ROS are produced as a physiological byproduct of various cellular processes, and are normally detoxified by enzymes and antioxidants to help maintain neuronal homeostasis. However, cellular injury can cause excessive ROS production, triggering a state of oxidative stress that can lead to neuronal cell death. ROS and intracellular zinc are intimately related, as ROS production can lead to oxidation of proteins that normally bind the metal, thereby causing the liberation of zinc in cytoplasmic compartments. Similarly, not only can zinc impair mitochondrial function, leading to excess ROS production, but it can also activate a variety of extra-mitochondrial ROS-generating signaling cascades. As such, numerous accounts of oxidative neuronal injury by ROS-producing sources appear to also require zinc. We suggest that zinc deregulation is a common, perhaps ubiquitous component of injurious oxidative processes in neurons. This review summarizes current findings on zinc dyshomeostasis-driven signaling cascades in oxidative stress and age-related neurodegeneration, with a focus on AD, in order to highlight the critical role of the intracellular liberation of the metal during oxidative neuronal injury.
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Affiliation(s)
- Meghan C McCord
- Department of Neurobiology, University of Pittsburgh School of Medicine Pittsburgh, PA, USA
| | - Elias Aizenman
- Department of Neurobiology, University of Pittsburgh School of Medicine Pittsburgh, PA, USA
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90
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Asraf H, Salomon S, Nevo A, Sekler I, Mayer D, Hershfinkel M. The ZnR/GPR39 Interacts With the CaSR to Enhance Signaling in Prostate and Salivary Epithelia. J Cell Physiol 2014; 229:868-77. [DOI: 10.1002/jcp.24514] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2013] [Accepted: 11/18/2013] [Indexed: 12/31/2022]
Affiliation(s)
- Hila Asraf
- Department of Physiology and Cell Biology, Faculty of Health Sciences; Ben-Gurion University of the Negev; Beer-Sheva Israel
| | - Shimrit Salomon
- Department of Physiology and Cell Biology, Faculty of Health Sciences; Ben-Gurion University of the Negev; Beer-Sheva Israel
| | - Andrey Nevo
- Department of Physiology and Cell Biology, Faculty of Health Sciences; Ben-Gurion University of the Negev; Beer-Sheva Israel
| | - Israel Sekler
- Department of Physiology and Cell Biology, Faculty of Health Sciences; Ben-Gurion University of the Negev; Beer-Sheva Israel
| | - Doris Mayer
- Hormones and Signal Transduction Group; German Cancer Research Center (DKFZ); Heidelberg Germany
| | - Michal Hershfinkel
- Department of Physiology and Cell Biology, Faculty of Health Sciences; Ben-Gurion University of the Negev; Beer-Sheva Israel
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91
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Medina I, Friedel P, Rivera C, Kahle KT, Kourdougli N, Uvarov P, Pellegrino C. Current view on the functional regulation of the neuronal K(+)-Cl(-) cotransporter KCC2. Front Cell Neurosci 2014; 8:27. [PMID: 24567703 PMCID: PMC3915100 DOI: 10.3389/fncel.2014.00027] [Citation(s) in RCA: 128] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2013] [Accepted: 01/18/2014] [Indexed: 12/22/2022] Open
Abstract
In the mammalian central nervous system (CNS), the inhibitory strength of chloride (Cl(-))-permeable GABAA and glycine receptors (GABAAR and GlyR) depends on the intracellular Cl(-) concentration ([Cl(-)]i). Lowering [Cl(-)]i enhances inhibition, whereas raising [Cl(-)]i facilitates neuronal activity. A neuron's basal level of [Cl(-)]i, as well as its Cl(-) extrusion capacity, is critically dependent on the activity of the electroneutral K(+)-Cl(-) cotransporter KCC2, a member of the SLC12 cation-Cl(-) cotransporter (CCC) family. KCC2 deficiency compromises neuronal migration, formation and the maturation of GABAergic and glutamatergic synaptic connections, and results in network hyperexcitability and seizure activity. Several neurological disorders including multiple epilepsy subtypes, neuropathic pain, and schizophrenia, as well as various insults such as trauma and ischemia, are associated with significant decreases in the Cl(-) extrusion capacity of KCC2 that result in increases of [Cl(-)]i and the subsequent hyperexcitability of neuronal networks. Accordingly, identifying the key upstream molecular mediators governing the functional regulation of KCC2, and modifying these signaling pathways with small molecules, might constitute a novel neurotherapeutic strategy for multiple diseases. Here, we discuss recent advances in the understanding of the mechanisms regulating KCC2 activity, and of the role these mechanisms play in neuronal Cl(-) homeostasis and GABAergic neurotransmission. As KCC2 mediates electroneutral transport, the experimental recording of its activity constitutes an important research challenge; we therefore also, provide an overview of the different methodological approaches utilized to monitor function of KCC2 in both physiological and pathological conditions.
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Affiliation(s)
- Igor Medina
- INSERM, Institut de Neurobiologie de la Méditerranée (INMED)Marseille, France
- Aix-Marseille Université, UMR901Marseille, France
| | - Perrine Friedel
- INSERM, Institut de Neurobiologie de la Méditerranée (INMED)Marseille, France
- Aix-Marseille Université, UMR901Marseille, France
| | - Claudio Rivera
- INSERM, Institut de Neurobiologie de la Méditerranée (INMED)Marseille, France
- Aix-Marseille Université, UMR901Marseille, France
- Neuroscience Center, University of HelsinkiHelsinki, Finland
| | - Kristopher T. Kahle
- Department of Cardiology, Manton Center for Orphan Disease Research, Howard Hughes Medical Institute, Boston Children's HospitalBoston, MA, USA
- Department of Neurosurgery, Massachusetts General Hospital and Harvard Medical SchoolBoston, MA, USA
| | - Nazim Kourdougli
- INSERM, Institut de Neurobiologie de la Méditerranée (INMED)Marseille, France
- Aix-Marseille Université, UMR901Marseille, France
| | - Pavel Uvarov
- Institute of Biomedicine, Anatomy, University of HelsinkiHelsinki, Finland
| | - Christophe Pellegrino
- INSERM, Institut de Neurobiologie de la Méditerranée (INMED)Marseille, France
- Aix-Marseille Université, UMR901Marseille, France
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92
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Xiao L, Kovac S, Chang M, Shulkes A, Baldwin GS, Patel O. Zinc ions upregulate the hormone gastrin via an E-box motif in the proximal gastrin promoter. J Mol Endocrinol 2014; 52:29-42. [PMID: 24363439 DOI: 10.1530/jme-13-0162] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Gastrin and its precursors act as growth factors for the normal and neoplastic gastrointestinal mucosa. As the hypoxia mimetic cobalt chloride upregulates the gastrin gene, the effect of other metal ions on gastrin promoter activity was investigated. Gastrin mRNA was measured by real-time PCR, gastrin peptides by RIA, and gastrin promoter activity by dual-luciferase reporter assay. Exposure to Zn(2)(+) ions increased gastrin mRNA concentrations in the human gastric adenocarcinoma cell line AGS in a dose-dependent manner, with a maximum stimulation of 55 ± 14-fold at 100 μM (P<0.05). Significant stimulation was also observed with Cd(2)(+) and Cu(2)(+), but not with Ca(2)(+), Mg(2)(+), Ni(2)(+), or Fe(3)(+) ions. Activation of MAPK and phosphatidylinositol 3-kinase pathways is necessary but not sufficient for gastrin induction by Zn(2)(+). Deletional mutation of the gastrin promoter identified an 11 bp DNA sequence, which contained an E-box motif, as necessary for Zn(2)(+)-dependent gastrin induction. The fact that E-box binding transcription factors play a crucial role in the epithelial-mesenchymal transition (EMT), together with our observation that Zn(2)(+) ions upregulate the gastrin gene in AGS cells by an E-box-dependent mechanism, suggests that Zn(2)(+) ions may induce an EMT, and that gastrin may be involved in the transition.
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Affiliation(s)
- Lin Xiao
- Department of Surgery, Austin Health, The University of Melbourne, Studley Road, Heidelberg, Victoria 3084, Australia
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93
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Nuttall JR, Oteiza PI. Zinc and the aging brain. GENES AND NUTRITION 2013; 9:379. [PMID: 24366781 DOI: 10.1007/s12263-013-0379-x] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/16/2013] [Accepted: 12/06/2013] [Indexed: 11/25/2022]
Abstract
Alterations in trace element homeostasis could be involved in the pathology of dementia, and in particular of Alzheimer's disease (AD). Zinc is a structural or functional component of many proteins, being involved in numerous and relevant physiological functions. Zinc homeostasis is affected in the elderly, and current evidence points to alterations in the cellular and systemic distribution of zinc in AD. Although the association of zinc and other metals with AD pathology remains unclear, therapeutic approaches designed to restore trace element homeostasis are being tested in clinical trials. Not only could zinc supplementation potentially benefit individuals with AD, but zinc supplementation also improves glycemic control in the elderly suffering from diabetes mellitus. However, the findings that select genetic polymorphisms may alter an individual's zinc intake requirements should be taken into consideration when planning zinc supplementation. This review will focus on current knowledge regarding pathological and protective mechanisms involving brain zinc in AD to highlight areas where future research may enable development of new and improved therapies.
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Affiliation(s)
- Johnathan R Nuttall
- Department of Nutrition, University of California, One Shields Av., Davis, CA, 95616, USA
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94
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Liu Z, Wang B, He R, Zhao Y, Miao L. Calcium signaling and the MAPK cascade are required for sperm activation in Caenorhabditis elegans. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2013; 1843:299-308. [PMID: 24239721 DOI: 10.1016/j.bbamcr.2013.11.001] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/16/2013] [Revised: 10/28/2013] [Accepted: 11/05/2013] [Indexed: 12/20/2022]
Abstract
In nematode, sperm activation (or spermiogenesis), a process in which the symmetric and non-motile spermatids transform into polarized and crawling spermatozoa, is critical for sperm cells to acquire fertilizing competence. SPE-8 dependent and SPE-8 independent pathways function redundantly during sperm activation in both males and hermaphrodites of Caenorhabditis elegans. However, the downstream signaling for both pathways remains unclear. Here we show that calcium signaling and the MAPK cascade are required for both SPE-8 dependent and SPE-8 independent sperm activation, implying that both pathways share common downstream signaling components during sperm activation. We demonstrate that activation of the MAPK cascade is sufficient to activate spermatids derived from either wild-type or spe-8 group mutant males and that activation of the MAPK cascade bypasses the requirement of calcium signal to induce sperm activation, indicating that the MAPK cascade functions downstream of or parallel with the calcium signaling during sperm activation. Interestingly, the persistent activation of MAPK in activated spermatozoa inhibits Major Sperm Protein (MSP)-based cytoskeleton dynamics. We demonstrate that MAPK plays dual roles in promoting pseudopod extension during sperm activation but also blocking the MSP-based, amoeboid motility of the spermatozoa. Thus, though nematode sperm are crawling cells, morphologically distinct from flagellated sperm, and the molecular machinery for motility of amoeboid and flagellated sperm is different, both types of sperm might utilize conserved signaling pathways to modulate sperm maturation.
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Affiliation(s)
- Zhiyu Liu
- Laboratory of Noncoding RNA, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Bin Wang
- Laboratory of Noncoding RNA, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China
| | - Ruijun He
- Laboratory of Noncoding RNA, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China
| | - Yanmei Zhao
- Laboratory of Noncoding RNA, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China
| | - Long Miao
- Laboratory of Noncoding RNA, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China.
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95
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Gagnon M, Bergeron MJ, Lavertu G, Castonguay A, Tripathy S, Bonin RP, Perez-Sanchez J, Boudreau D, Wang B, Dumas L, Valade I, Bachand K, Jacob-Wagner M, Tardif C, Kianicka I, Isenring P, Attardo G, Coull JA, De Koninck Y. Chloride extrusion enhancers as novel therapeutics for neurological diseases. Nat Med 2013; 19:1524-8. [PMID: 24097188 PMCID: PMC4005788 DOI: 10.1038/nm.3356] [Citation(s) in RCA: 233] [Impact Index Per Article: 21.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2013] [Accepted: 08/21/2013] [Indexed: 12/19/2022]
Abstract
The K(+)-Cl(-) cotransporter KCC2 is responsible for maintaining low Cl(-) concentration in neurons of the central nervous system (CNS), which is essential for postsynaptic inhibition through GABA(A) and glycine receptors. Although no CNS disorders have been associated with KCC2 mutations, loss of activity of this transporter has emerged as a key mechanism underlying several neurological and psychiatric disorders, including epilepsy, motor spasticity, stress, anxiety, schizophrenia, morphine-induced hyperalgesia and chronic pain. Recent reports indicate that enhancing KCC2 activity may be the favored therapeutic strategy to restore inhibition and normal function in pathological conditions involving impaired Cl(-) transport. We designed an assay for high-throughput screening that led to the identification of KCC2 activators that reduce intracellular chloride concentration ([Cl(-)]i). Optimization of a first-in-class arylmethylidine family of compounds resulted in a KCC2-selective analog (CLP257) that lowers [Cl(-)]i. CLP257 restored impaired Cl(-) transport in neurons with diminished KCC2 activity. The compound rescued KCC2 plasma membrane expression, renormalized stimulus-evoked responses in spinal nociceptive pathways sensitized after nerve injury and alleviated hypersensitivity in a rat model of neuropathic pain. Oral efficacy for analgesia equivalent to that of pregabalin but without motor impairment was achievable with a CLP257 prodrug. These results validate KCC2 as a druggable target for CNS diseases.
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Affiliation(s)
- Martin Gagnon
- Institut universitaire en santé mentale de Québec, Qc
- Department of Psychiatry & Neuroscience, Université Laval, Québec, Qc
- Chlorion Pharma, Inc. Laval, Qc
| | - Marc J. Bergeron
- Institut universitaire en santé mentale de Québec, Qc
- Department of Psychiatry & Neuroscience, Université Laval, Québec, Qc
| | - Guillaume Lavertu
- Institut universitaire en santé mentale de Québec, Qc
- Department of Psychiatry & Neuroscience, Université Laval, Québec, Qc
| | - Annie Castonguay
- Institut universitaire en santé mentale de Québec, Qc
- Department of Psychiatry & Neuroscience, Université Laval, Québec, Qc
| | | | - Robert P. Bonin
- Institut universitaire en santé mentale de Québec, Qc
- Department of Psychiatry & Neuroscience, Université Laval, Québec, Qc
| | - Jimena Perez-Sanchez
- Institut universitaire en santé mentale de Québec, Qc
- Department of Psychiatry & Neuroscience, Université Laval, Québec, Qc
| | - Dominic Boudreau
- Institut universitaire en santé mentale de Québec, Qc
- Department of Psychiatry & Neuroscience, Université Laval, Québec, Qc
| | | | | | | | - Karine Bachand
- Institut universitaire en santé mentale de Québec, Qc
- Department of Psychiatry & Neuroscience, Université Laval, Québec, Qc
| | | | - Christian Tardif
- Institut universitaire en santé mentale de Québec, Qc
- Graduate program in biophotonics, Université Laval, Québec, Qc
| | | | - Paul Isenring
- Centre de recherche du Centre Hospitalier Universitaire de Québec, Qc
| | | | | | - Yves De Koninck
- Institut universitaire en santé mentale de Québec, Qc
- Department of Psychiatry & Neuroscience, Université Laval, Québec, Qc
- Graduate program in biophotonics, Université Laval, Québec, Qc
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96
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Pang W, Leng X, Lu H, Yang H, Song N, Tan L, Jiang Y, Guo C. Depletion of intracellular zinc induces apoptosis of cultured hippocampal neurons through suppression of ERK signaling pathway and activation of caspase-3. Neurosci Lett 2013; 552:140-5. [PMID: 23954826 DOI: 10.1016/j.neulet.2013.07.057] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2013] [Revised: 07/15/2013] [Accepted: 07/31/2013] [Indexed: 11/19/2022]
Abstract
Although Zinc depletion induces apoptosis in different cells and tissues, exact mechanism of this action of zinc depletion is not completely understood. In our previous study, the results suggested that the significant down-regulation of MEK/ERK signaling pathway was observed in zinc deficiency neurons. Here, we investigate whether, in hippocampal neurons, this increased rate of apoptosis induced by zinc depletion is the result of hypophosphorylation of ERK pathway. In this study, we found that NGF, ERK agonist, prevented neurons against TPEN-induced apoptosis, whereas TPEN-induced apoptosis was potentiated by U0126, inhibitors of ERK. Moreover, TPEN-induced caspase-3 activity was further increased by the pretreatment with U0126, but it was further decreased by the pretreatment with NGF. However, pretreatment of the cells with U0126 or NGF had no effect on the changes of Bcl-2 and Bax protein expression induced by zinc depletion. Thus, the results indicate that TPEN induces apoptosis of hippocampal neurons through inhibition of ERK and, in turn, activation of caspase-3.
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Affiliation(s)
- Wei Pang
- Department of Nutrition, Institute of Hygiene & Environmental Medicine, Academy of Military Medical Science, Tianjin, China
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97
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Enhanced susceptibility to spontaneous seizures of noda epileptic rats by loss of synaptic zn(2+). PLoS One 2013; 8:e71372. [PMID: 23951148 PMCID: PMC3741169 DOI: 10.1371/journal.pone.0071372] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2012] [Accepted: 07/04/2013] [Indexed: 01/21/2023] Open
Abstract
Zinc homeostasis in the brain is associated with the etiology and manifestation of epileptic seizures. Adult Noda epileptic rats (NER, >12-week-old) exhibit spontaneously generalized tonic-clonic convulsion about once a day. To pursue the involvement of synaptic Zn2+ signal in susceptibility to spontaneous seizures, in the present study, the effect of zinc chelators on epileptogenesis was examined using adult NER. Clioquinol (CQ) and TPEN are lipophilic zinc chelotors, transported into the brain and reduce the levels of synaptic Zn2+. The incidence of tonic-clonic convulsion was markedly increased after i.p. injection of CQ (30–100 mg/kg) and TPEN (1 mg/kg). The basal levels of extracellular Zn2+ measured by ZnAF-2 were decreased before tonic-clonic convulsion was induced with zinc chelators. The hippocampal electroencephalograms during CQ (30 mg/kg)-induced convulsions were similar to those during sound-induced convulsions in NER reported previously. Exocytosis of hippocampal mossy fibers, which was measured with FM4-64, was significantly increased in hippocampal slices from CQ-injected NER that did not show tonic-clonic convulsion yet. These results indicate that the abnormal excitability of mossy fibers is induced prior to epileptic seizures by injection of zinc chelators into NER. The incidence of tonic-clonic convulsion induced with CQ (30 mg/kg) was significantly reduced by co-injection with aminooxyacetic acid (5–10 mg/kg), an anticonvulsant drug enhancing GABAergic activity, which did not affect locomotor activity. The present paper demonstrates that the abnormal excitability in the brain, especially in mossy fibers, which is potentially associated with the insufficient GABAergic neuron activity, may be a factor to reduce the threshold for epileptogenesis in NER.
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98
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Abstract
Although it is well established that many glutamatergic neurons sequester Zn(2+) within their synaptic vesicles, the physiological significance of synaptic Zn(2+) remains poorly understood. In experiments performed in a Zn(2+)-enriched auditory brainstem nucleus--the dorsal cochlear nucleus--we discovered that synaptic Zn(2+) and GPR39, a putative metabotropic Zn(2+)-sensing receptor (mZnR), are necessary for triggering the synthesis of the endocannabinoid 2-arachidonoylglycerol (2-AG). The postsynaptic production of 2-AG, in turn, inhibits presynaptic probability of neurotransmitter release, thus shaping synaptic strength and short-term synaptic plasticity. Zn(2+)-induced inhibition of transmitter release is absent in mutant mice that lack either vesicular Zn(2+) or the mZnR. Moreover, mass spectrometry measurements of 2-AG levels reveal that Zn(2+)-mediated initiation of 2-AG synthesis is absent in mice lacking the mZnR. We reveal a previously unknown action of synaptic Zn(2+): synaptic Zn(2+) inhibits glutamate release by promoting 2-AG synthesis.
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Singla N, Dhawan D. Zinc protection against aluminium induced altered lipid profile and membrane integrity. Food Chem Toxicol 2013; 55:18-28. [DOI: 10.1016/j.fct.2012.12.047] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2012] [Revised: 12/25/2012] [Accepted: 12/27/2012] [Indexed: 12/14/2022]
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Ferrini F, Trang T, Mattioli TAM, Laffray S, Del’Guidice T, Lorenzo LE, Castonguay A, Doyon N, Zhang W, Godin AG, Mohr D, Beggs S, Vandal K, Beaulieu JM, Cahill C, Salter MW, De Koninck Y. Morphine hyperalgesia gated through microglia-mediated disruption of neuronal Cl⁻ homeostasis. Nat Neurosci 2013; 16:183-92. [PMID: 23292683 PMCID: PMC4974077 DOI: 10.1038/nn.3295] [Citation(s) in RCA: 324] [Impact Index Per Article: 29.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2012] [Accepted: 12/05/2012] [Indexed: 01/18/2023]
Abstract
A major unresolved issue in treating pain is the paradoxical hyperalgesia produced by the gold-standard analgesic morphine and other opiates. We found that hyperalgesia-inducing treatment with morphine resulted in downregulation of the K(+)-Cl(-) co-transporter KCC2, impairing Cl(-) homeostasis in rat spinal lamina l neurons. Restoring the anion equilibrium potential reversed the morphine-induced hyperalgesia without affecting tolerance. The hyperalgesia was also reversed by ablating spinal microglia. Morphine hyperalgesia, but not tolerance, required μ opioid receptor-dependent expression of P2X4 receptors (P2X4Rs) in microglia and μ-independent gating of the release of brain-derived neurotrophic factor (BDNF) by P2X4Rs. Blocking BDNF-TrkB signaling preserved Cl(-) homeostasis and reversed the hyperalgesia. Gene-targeted mice in which Bdnf was deleted from microglia did not develop hyperalgesia to morphine. However, neither morphine antinociception nor tolerance was affected in these mice. Our findings dissociate morphine-induced hyperalgesia from tolerance and suggest the microglia-to-neuron P2X4-BDNF-KCC2 pathway as a therapeutic target for preventing hyperalgesia without affecting morphine analgesia.
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Affiliation(s)
- Francesco Ferrini
- Institut Universitaire de santé mentale de Québec, Québec, G1J 2G3, Canada
- Department of Psychiatry and Neuroscience, Université Laval, Québec, Québec, G13 7P4, Canada
- Department of Veterinary Sciences, University of Turin, 10095, Grugliasco, Turin, Italy
| | - Tuan Trang
- Program in Neurosciences & Mental Health, Hospital for Sick Children, Toronto, Ontario, M5G 1X8, Canada
- Department of Physiology, University of Toronto, Toronto, Ontario, Canada
- Departments of Comparative Biology & Experimental Medicine, and Physiology & Pharmacology, Hotchkiss Brain Institute, University of Calgary, Calgary, Canada
| | - Theresa-Alexandra M. Mattioli
- Departments of Comparative Biology & Experimental Medicine, and Physiology & Pharmacology, Hotchkiss Brain Institute, University of Calgary, Calgary, Canada
| | - Sophie Laffray
- Institut Universitaire de santé mentale de Québec, Québec, G1J 2G3, Canada
- Department of Psychiatry and Neuroscience, Université Laval, Québec, Québec, G13 7P4, Canada
| | - Thomas Del’Guidice
- Institut Universitaire de santé mentale de Québec, Québec, G1J 2G3, Canada
- Department of Psychiatry and Neuroscience, Université Laval, Québec, Québec, G13 7P4, Canada
| | - Louis-Etienne Lorenzo
- Institut Universitaire de santé mentale de Québec, Québec, G1J 2G3, Canada
- Department of Psychiatry and Neuroscience, Université Laval, Québec, Québec, G13 7P4, Canada
| | - Annie Castonguay
- Institut Universitaire de santé mentale de Québec, Québec, G1J 2G3, Canada
- Department of Psychiatry and Neuroscience, Université Laval, Québec, Québec, G13 7P4, Canada
| | - Nicolas Doyon
- Institut Universitaire de santé mentale de Québec, Québec, G1J 2G3, Canada
- Department of Psychiatry and Neuroscience, Université Laval, Québec, Québec, G13 7P4, Canada
| | - Wenbo Zhang
- Program in Neurosciences & Mental Health, Hospital for Sick Children, Toronto, Ontario, M5G 1X8, Canada
- Department of Physiology, University of Toronto, Toronto, Ontario, Canada
| | - Antoine G. Godin
- Institut Universitaire de santé mentale de Québec, Québec, G1J 2G3, Canada
| | - Daniela Mohr
- Program in Neurosciences & Mental Health, Hospital for Sick Children, Toronto, Ontario, M5G 1X8, Canada
- Department of Physiology, University of Toronto, Toronto, Ontario, Canada
| | - Simon Beggs
- Program in Neurosciences & Mental Health, Hospital for Sick Children, Toronto, Ontario, M5G 1X8, Canada
- Department of Physiology, University of Toronto, Toronto, Ontario, Canada
| | - Karen Vandal
- Institut Universitaire de santé mentale de Québec, Québec, G1J 2G3, Canada
| | - Jean-Martin Beaulieu
- Institut Universitaire de santé mentale de Québec, Québec, G1J 2G3, Canada
- Department of Psychiatry and Neuroscience, Université Laval, Québec, Québec, G13 7P4, Canada
| | - Catherine Cahill
- Department of Pharmacology & Toxicology, Queen’s University, Kingston, Ontario, Canada
| | - Michael W. Salter
- Program in Neurosciences & Mental Health, Hospital for Sick Children, Toronto, Ontario, M5G 1X8, Canada
- Department of Physiology, University of Toronto, Toronto, Ontario, Canada
| | - Yves De Koninck
- Institut Universitaire de santé mentale de Québec, Québec, G1J 2G3, Canada
- Department of Psychiatry and Neuroscience, Université Laval, Québec, Québec, G13 7P4, Canada
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