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Mizuno D, Kawahara M, Konoha-Mizuno K, Hama R, Ogawara T. The Role of Zinc in the Development of Vascular Dementia and Parkinson's Disease and the Potential of Carnosine as Their Therapeutic Agent. Biomedicines 2024; 12:1296. [PMID: 38927502 PMCID: PMC11201809 DOI: 10.3390/biomedicines12061296] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2024] [Revised: 05/10/2024] [Accepted: 06/07/2024] [Indexed: 06/28/2024] Open
Abstract
Synaptic zinc ions (Zn2+) play an important role in the development of vascular dementia (VD) and Parkinson's disease (PD). In this article, we reviewed the current comprehension of the Zn2+-induced neurotoxicity that leads to the pathogenesis of these neuronal diseases. Zn2+-induced neurotoxicity was investigated by using immortalised hypothalamic neurons (GT1-7 cells). This cell line is useful for the development of a rapid and convenient screening system for investigating Zn2+-induced neurotoxicity. GT1-7 cells were also used to search for substances that prevent Zn2+-induced neurotoxicity. Among the tested substances was a protective substance in the extract of Japanese eel (Anguilla japonica), and we determined its structure to be like carnosine (β-alanylhistidine). Carnosine may be a therapeutic drug for VD and PD. Furthermore, we reviewed the molecular mechanisms that involve the role of carnosine as an endogenous protector and its protective effect against Zn2+-induced cytotoxicity and discussed the prospects for the future therapeutic applications of this dipeptide for neurodegenerative diseases and dementia.
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Affiliation(s)
- Dai Mizuno
- Department of Forensic Medicine, Faculty of Medicine, Yamagata University, 2-2-2 Iida-Nishi, Yamagata-shi 990-9585, Yamagata, Japan; (K.K.-M.); (R.H.); (T.O.)
| | - Masahiro Kawahara
- Research Institute of Pharmaceutical Sciences, Faculty of Pharmacy, Musashino University, 1-1-20 Shin-machi, Nishitokyo-shi 202-8585, Tokyo, Japan;
| | - Keiko Konoha-Mizuno
- Department of Forensic Medicine, Faculty of Medicine, Yamagata University, 2-2-2 Iida-Nishi, Yamagata-shi 990-9585, Yamagata, Japan; (K.K.-M.); (R.H.); (T.O.)
| | - Ryoji Hama
- Department of Forensic Medicine, Faculty of Medicine, Yamagata University, 2-2-2 Iida-Nishi, Yamagata-shi 990-9585, Yamagata, Japan; (K.K.-M.); (R.H.); (T.O.)
| | - Terumasa Ogawara
- Department of Forensic Medicine, Faculty of Medicine, Yamagata University, 2-2-2 Iida-Nishi, Yamagata-shi 990-9585, Yamagata, Japan; (K.K.-M.); (R.H.); (T.O.)
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2
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Benarroch E. What Are the Functions of Zinc in the Nervous System? Neurology 2023; 101:714-720. [PMID: 37845046 PMCID: PMC10585682 DOI: 10.1212/wnl.0000000000207912] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2023] [Accepted: 08/16/2023] [Indexed: 10/18/2023] Open
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A multimodal electrochemical approach to measure the effect of zinc on vesicular content and exocytosis in a single cell model of ischemia. QRB DISCOVERY 2021. [PMID: 37529672 PMCID: PMC10392633 DOI: 10.1017/qrd.2021.10] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Abstract
Zinc ion is essential for normal brain function that modulates synaptic activity and neuronal plasticity and it is associated with memory formation. Zinc is considered to be a contributing factor to the pathogenesis of ischemia, but the association between zinc and ischemia on vesicular exocytosis is unclear. In this study, we used a combination of chemical analysis methods and a cell model of ischemia/reperfusion to investigate exocytotic release and vesicular content, as well as the effect of zinc alteration on vesicular exocytosis. Oxygen–glucose deprivation and reperfusion (OGDR) was used as an in vitro model of ischemia in a model cell line. Exocytotic release and vesicular storage of catecholamine content were increased following OGDR, resulting in a higher fraction of release during exocytosis. However, zinc eliminated these increases following OGDR and the fraction of release remained unchanged. Understanding the consequences of zinc accumulation on vesicular exocytosis at the early stage of OGDR should aid in the development of therapeutic strategies to reduce ischemic brain injury. As the fraction released has been suggested to be related to presynaptic plasticity, insights are gained towards deciphering ischemia related memory impairment.
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Zinc in the Brain: Friend or Foe? Int J Mol Sci 2020; 21:ijms21238941. [PMID: 33255662 PMCID: PMC7728061 DOI: 10.3390/ijms21238941] [Citation(s) in RCA: 48] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2020] [Revised: 11/22/2020] [Accepted: 11/24/2020] [Indexed: 12/12/2022] Open
Abstract
Zinc is a trace metal ion in the central nervous system that plays important biological roles, such as in catalysis, structure, and regulation. It contributes to antioxidant function and the proper functioning of the immune system. In view of these characteristics of zinc, it plays an important role in neurophysiology, which leads to cell growth and cell proliferation. However, after brain disease, excessively released and accumulated zinc ions cause neurotoxic damage to postsynaptic neurons. On the other hand, zinc deficiency induces degeneration and cognitive decline disorders, such as increased neuronal death and decreased learning and memory. Given the importance of balance in this context, zinc is a biological component that plays an important physiological role in the central nervous system, but a pathophysiological role in major neurological disorders. In this review, we focus on the multiple roles of zinc in the brain.
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Kawahara M, Sadakane Y, Mizuno K, Kato-Negishi M, Tanaka KI. Carnosine as a Possible Drug for Zinc-Induced Neurotoxicity and Vascular Dementia. Int J Mol Sci 2020; 21:ijms21072570. [PMID: 32272780 PMCID: PMC7177235 DOI: 10.3390/ijms21072570] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2020] [Revised: 03/31/2020] [Accepted: 03/31/2020] [Indexed: 12/14/2022] Open
Abstract
Increasing evidence suggests that the metal homeostasis is involved in the pathogenesis of various neurodegenerative diseases including senile type of dementia such as Alzheimer’s disease, dementia with Lewy bodies, and vascular dementia. In particular, synaptic Zn2+ is known to play critical roles in the pathogenesis of vascular dementia. In this article, we review the molecular pathways of Zn2+-induced neurotoxicity based on our and numerous other findings, and demonstrated the implications of the energy production pathway, the disruption of calcium homeostasis, the production of reactive oxygen species (ROS), the endoplasmic reticulum (ER)-stress pathway, and the stress-activated protein kinases/c-Jun amino-terminal kinases (SAPK/JNK) pathway. Furthermore, we have searched for substances that protect neurons from Zn2+-induced neurotoxicity among various agricultural products and determined carnosine (β-alanyl histidine) as a possible therapeutic agent for vascular dementia.
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Affiliation(s)
- Masahiro Kawahara
- Department of Bio-Analytical Chemistry, Faculty of Pharmacy, Musashino University, Tokyo 202-8585, Japan; (M.K.-N.); (K.T.)
- Correspondence: ; Tel.: +81–42–468–8299
| | - Yutaka Sadakane
- Graduate School of Pharmaceutical Sciences, Suzuka University of Medical Science, Suzuka 513-8670, Japan;
| | - Keiko Mizuno
- Department of Forensic Medicine, Faculty of Medicine, Yamagata University, Yamagata 990-9585, Japan;
| | - Midori Kato-Negishi
- Department of Bio-Analytical Chemistry, Faculty of Pharmacy, Musashino University, Tokyo 202-8585, Japan; (M.K.-N.); (K.T.)
| | - Ken-ichiro Tanaka
- Department of Bio-Analytical Chemistry, Faculty of Pharmacy, Musashino University, Tokyo 202-8585, Japan; (M.K.-N.); (K.T.)
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Pushie MJ, Crawford AM, Sylvain NJ, Hou H, Hackett MJ, George GN, Kelly ME. Revealing the Penumbra through Imaging Elemental Markers of Cellular Metabolism in an Ischemic Stroke Model. ACS Chem Neurosci 2018; 9:886-893. [PMID: 29370523 DOI: 10.1021/acschemneuro.7b00382] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Stroke exacts a heavy financial and economic burden, is a leading cause of death, and is the leading cause of long-term disability in those who survive. The penumbra surrounds the ischemic core of the stroke lesion and is composed of cells that are stressed and vulnerable to death, which is due to an altered metabolic, oxidative, and ionic environment within the penumbra. Without therapeutic intervention, many cells within the penumbra will die and become part of the growing infarct, however, there is hope that appropriate therapies may allow potential recovery of cells within this tissue region, or at least slow the rate of cell death, therefore, slowing the spread of the ischemic infarct and minimizing the extent of tissue damage. As such, preserving the penumbra to promote functional brain recovery is a central goal in stroke research. While identification of the ischemic infarct, and the infarct/penumbra boundary is relatively trivial using classical histology and microscopy techniques, accurately assessing the penetration of the penumbra zone into undamaged brain tissue, and evaluating the magnitude of chemical alterations in the penumbra, has long been a major challenge to the stroke research field. In this study, we have used synchrotron-based X-ray fluorescence imaging to visualize the elemental changes in undamaged, penumbra, and infarct brain tissue, following ischemic stroke. We have employed a Gaussian mixture model to cluster tissue areas based on their elemental characteristics. The method separates the core of the infarct from healthy tissue, and also demarcates discrete regions encircling the infarct. These regions of interest can be combined with elemental and metabolic data, as well as with conventional histology. The cell populations defined by clustering provide a reproducible means of visualizing the size and extent of the penumbra at the level of the single cell and provide a critically needed tool to track changes in elemental status and penumbra size.
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Affiliation(s)
- M. Jake Pushie
- Department of Surgery, Division of Neurosurgery, College of Medicine, University of Saskatchewan, 107 Wiggins Road, Saskatoon, Saskatchewan S7N 5E5, Canada
| | - Andrew M. Crawford
- Geological Sciences, College of Arts & Science, University of Saskatchewan, 114 Science Place, Saskatoon, Saskatchewan S7N 5E2, Canada
| | - Nicole J. Sylvain
- Department of Surgery, Division of Neurosurgery, College of Medicine, University of Saskatchewan, 107 Wiggins Road, Saskatoon, Saskatchewan S7N 5E5, Canada
| | - Huishu Hou
- Department of Surgery, Division of Neurosurgery, College of Medicine, University of Saskatchewan, 107 Wiggins Road, Saskatoon, Saskatchewan S7N 5E5, Canada
| | - Mark J. Hackett
- Curtin Institute for Functional Molecules and Interfaces, Department of Chemistry, Faculty of Science & Engineering, Curtin University, Kent Street, Bentley, Perth, Western Australia 6102, Australia
- Curtin Health Innovation Research Institute, Curtin University, Bentley, Western Australia 6102, Australia
| | - Graham N. George
- Geological Sciences, College of Arts & Science, University of Saskatchewan, 114 Science Place, Saskatoon, Saskatchewan S7N 5E2, Canada
| | - Michael E. Kelly
- Department of Surgery, Division of Neurosurgery, College of Medicine, University of Saskatchewan, 107 Wiggins Road, Saskatoon, Saskatchewan S7N 5E5, Canada
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7
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Zinc Potentiates Lipopolysaccharide-induced Nitric Oxide Production in Cultured Primary Rat Astrocytes. Neurochem Res 2017; 43:363-374. [DOI: 10.1007/s11064-017-2431-5] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2017] [Revised: 10/04/2017] [Accepted: 11/01/2017] [Indexed: 01/28/2023]
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8
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Zhong YH, Dhawan J, Kovoor JA, Sullivan J, Zhang WX, Choi D, Biegon A. Aromatase and neuroinflammation in rat focal brain ischemia. J Steroid Biochem Mol Biol 2017; 174:225-233. [PMID: 28964927 DOI: 10.1016/j.jsbmb.2017.09.019] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/16/2017] [Revised: 09/24/2017] [Accepted: 09/25/2017] [Indexed: 12/22/2022]
Abstract
Accumulating evidence suggests that expression of aromatase, the enzyme responsible for the conversion of androgens to estrogens, is transiently upregulated in rat stroke models. It was further suggested that increased aromatase expression is linked to neuroinflammation and that it is neuroprotective in females. Our goal was to investigate aromatase upregulation in male rats subjected to experimental stroke in relationship to neuroinflammation, infarct and response to treatment with different putative neuroprotective agents. Intact male rats were subjected to transient (90min) middle cerebral artery occlusion (MCAO) and administered selfotel (N-methyl-d-aspartic acid (NMDA) receptor competitive antagonist), TPEN (a zinc chelator), a combination of the two drugs or vehicle, injected immediately after reperfusion. Animals were killed 14days after MCAO and consecutive brain sections used to measure aromatase expression, cerebral infarct volume and neuroinflammation. Quantitative immunohistochemistry (IHC) demonstrated increased brain aromatase expression in the peri-infarct area relative to contralesional area, which was partially abrogated by neuroprotective agents. There was no correlation between aromatase expression in the peri-infarct zone and infarct volume, which was reduced by neuroprotective agents. Microglial activation, measured by quantitative autoradiography, was positively correlated with infarct and inversely correlated with aromatase expression in the peri-infarct zone. Our findings indicate that focal ischemia upregulates brain aromatase in the male rat brain at 14days post surgery, which is within the time frame documented in females. However, the lack of negative correlation between aromatase expression and infarct volume and lack of positive correlation between microgliosis and aromatase do not support a major role for aromatase as a mediator of neuroprotection or a causal relationship between microglial activation and increased aromatase expression in male focal ischemia.
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Affiliation(s)
- Yu H Zhong
- Department of Neurology, the First Affiliated Hospital of Sun Yat-Sen University, No. 58, Zhongshan Road II, Guangzhou, Guangdong Province 510080, PR China; Department of Neurology, Stony Brook University, 100 Nicolls Road, Stony Brook, NY 11794-2565, USA.
| | - Jasbeer Dhawan
- Department of Neurology, Stony Brook University, 100 Nicolls Road, Stony Brook, NY 11794-2565, USA.
| | - Joel A Kovoor
- Department of Neurology, Stony Brook University, 100 Nicolls Road, Stony Brook, NY 11794-2565, USA.
| | - John Sullivan
- Department of Neurology, Stony Brook University, 100 Nicolls Road, Stony Brook, NY 11794-2565, USA.
| | - Wei X Zhang
- Department of Neurology, the First Affiliated Hospital of Sun Yat-Sen University, No. 58, Zhongshan Road II, Guangzhou, Guangdong Province 510080, PR China.
| | - Dennis Choi
- Department of Neurology, Stony Brook University, 100 Nicolls Road, Stony Brook, NY 11794-2565, USA.
| | - Anat Biegon
- Department of Neurology, Stony Brook University, 100 Nicolls Road, Stony Brook, NY 11794-2565, USA.
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9
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Qi Z, Liang J, Pan R, Dong W, Shen J, Yang Y, Zhao Y, Shi W, Luo Y, Ji X, Liu KJ. Zinc contributes to acute cerebral ischemia-induced blood-brain barrier disruption. Neurobiol Dis 2016; 95:12-21. [PMID: 27388935 DOI: 10.1016/j.nbd.2016.07.003] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2016] [Revised: 06/12/2016] [Accepted: 07/03/2016] [Indexed: 12/14/2022] Open
Abstract
Zinc ions are stored in synaptic vesicles and cerebral ischemia triggers their release from the terminals of neurons. Zinc accumulation in neurons has been shown to play an important role in neuronal death following ischemia. However, almost nothing is known about whether zinc is involved in ischemia-induced blood-brain barrier (BBB) disruption. Herein, we investigated the contribution of zinc to ischemia-induced acute BBB disruption and the possible molecular mechanisms using both cellular and animal models of cerebral ischemia. Zinc greatly increased BBB permeability and exacerbated the loss of tight junction proteins (Occludin and Claudin-5) in the endothelial monolayer under oxygen glucose deprivation conditions. In cerebral ischemic rats, a dramatically elevated level of zinc accumulation in microvessels themselves was observed in isolated microvessels and in situ, showing the direct interaction of zinc on ischemic microvessels. Treatment with a specific zinc chelator N,N,N',N'-tetrakis(2-pyridylmethyl) ethylenediamine (TPEN), even at 60-min post-ischemia onset, could greatly attenuate BBB permeability in the ischemic rats as measured by Evan's Blue extravasation, edema volume and magnetic resonance imaging. Furthermore, zinc accumulation in microvessels activated the superoxide/matrix metalloproteinase-9/-2 pathway, which leads to the loss of tight junction proteins (Occludin and Claudin-5) and death of endothelial cells in microvessels themselves. Our findings reveal a novel mechanism of cerebral ischemia-induced BBB damage, and implicate zinc as an effective and viable new target for reducing acute BBB damage following ischemic stroke.
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Affiliation(s)
- Zhifeng Qi
- Cerebrovascular Diseases Research Institute, Xuanwu hospital of Capital Medical University, 45 Changchun Street, Beijing 100053, China; Department of Pharmaceutical Sciences, University of New Mexico, Albuquerque, NM 87131-0001, USA
| | - Jia Liang
- Central Laboratory of Liaoning Medical University, Jinzhou, Liaoning, China
| | - Rong Pan
- Department of Pharmaceutical Sciences, University of New Mexico, Albuquerque, NM 87131-0001, USA
| | - Wen Dong
- Cerebrovascular Diseases Research Institute, Xuanwu hospital of Capital Medical University, 45 Changchun Street, Beijing 100053, China
| | - Jiangang Shen
- School of Chinese Medicine, University of Hong Kong, Hong Kong, Hong Kong
| | - Yirong Yang
- Department of Pharmaceutical Sciences, University of New Mexico, Albuquerque, NM 87131-0001, USA
| | - Yongmei Zhao
- Cerebrovascular Diseases Research Institute, Xuanwu hospital of Capital Medical University, 45 Changchun Street, Beijing 100053, China
| | - Wenjuan Shi
- Cerebrovascular Diseases Research Institute, Xuanwu hospital of Capital Medical University, 45 Changchun Street, Beijing 100053, China
| | - Yumin Luo
- Cerebrovascular Diseases Research Institute, Xuanwu hospital of Capital Medical University, 45 Changchun Street, Beijing 100053, China
| | - Xunming Ji
- Cerebrovascular Diseases Research Institute, Xuanwu hospital of Capital Medical University, 45 Changchun Street, Beijing 100053, China
| | - Ke Jian Liu
- Cerebrovascular Diseases Research Institute, Xuanwu hospital of Capital Medical University, 45 Changchun Street, Beijing 100053, China; Department of Pharmaceutical Sciences, University of New Mexico, Albuquerque, NM 87131-0001, USA.
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Oxidative stress upregulates zinc uptake activity via Zrt/Irt-like protein 1 (ZIP1) in cultured mouse astrocytes. Life Sci 2016; 151:305-312. [DOI: 10.1016/j.lfs.2016.03.025] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2015] [Revised: 03/09/2016] [Accepted: 03/11/2016] [Indexed: 11/22/2022]
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Jiang Q, Guo Z, Zhao Y, Wang F, Mao L. In vivo fluorescence sensing of the salicylate-induced change of zinc ion concentration in the auditory cortex of rat brain. Analyst 2015; 140:197-203. [PMID: 25298977 DOI: 10.1039/c4an01443j] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
This study demonstrates a fluorescence method for in vivo sensing of the dynamic change of Zn(2+) concentration in auditory cortex microdialysates induced by salicylate with N'-(7-nitro-2,1,3-benzoxadiazole-4-yl)-N,N,N'-tris(pyridine-2-ylmethyl) ethane-1,2-diamine (NBD-TPEA) as a probe. The excellent properties of the NBD-TPEA probe make it possible to achieve a high selectivity for Zn(2+) sensing with the co-existence of amino acids and other metal ions as well as the species commonly existing in the cerebral system. To validate the method for in vivo fluorescence sensing of Zn(2+) in the rat brain, we pre-mix the microdialysates in vivo sampled from the auditory cortex with the NBD-TPEA probe and then perfuse the mixtures into a fluorescent cuvette for continuous-flow fluorescence detection. The method demonstrated here shows a linear relationship between the signal output and Zn(2+) concentration within the concentration range from 0.5 μM to 4 μM, with a detection limit of 156 nM (S/N = 3). The basal level of extracellular Zn(2+) in auditory cortex microdialysates is determined to be 0.52 ± 0.082 μM (n = 4). This value is increased by the injection of 100 mg mL(-1) of salicylate (1 μL min(-1), 5 min, i.p.), reaches a peak at the time point of 90 min, and levels off with time. Such an increase is attenuated by the injection of MK-801, a potent and specific NMDA receptor antagonist, after the pre-injection of 100 mg mL(-1) salicylate for 5 min. This study offers a fluorescence method for in vivo sensing of Zn(2+) in the rat brain that could be useful for the investigations of chemical processes involved in brain functions.
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Affiliation(s)
- Qin Jiang
- Beijing National Laboratory for Molecular Sciences, Key Laboratory of Analytical Chemistry for Living Biosystems, Institute of Chemistry, The Chinese Academy of Sciences, Beijing 100190, P. R. China.
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Ehling P, Cerina M, Budde T, Meuth SG, Bittner S. The CNS under pathophysiologic attack--examining the role of K₂p channels. Pflugers Arch 2014; 467:959-72. [PMID: 25482672 DOI: 10.1007/s00424-014-1664-2] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2014] [Revised: 11/17/2014] [Accepted: 11/28/2014] [Indexed: 10/24/2022]
Abstract
Members of the two-pore domain K(+) channel (K2P) family are increasingly recognized as being potential targets for therapeutic drugs and could play a role in the diagnosis and treatment of neurologic disorders. Their broad and diverse expression pattern in pleiotropic cell types, importance in cellular function, unique biophysical properties, and sensitivity toward pathophysiologic parameters represent the basis for their involvement in disorders of the central nervous system (CNS). This review will focus on multiple sclerosis (MS) and stroke, as there is growing evidence for the involvement of K2P channels in these two major CNS disorders. In MS, TASK1-3 channels are expressed on T lymphocytes and are part of a signaling network regulating Ca(2+)- dependent pathways that are mandatory for T cell activation, differentiation, and effector functions. In addition, TASK1 channels are involved in neurodegeneration, resulting in autoimmune attack of CNS cells. On the blood-brain barrier, TREK1 channels regulate immune cell trafficking under autoinflammatory conditions. Cerebral ischemia shares some pathophysiologic similarities with MS, including hypoxia and extracellular acidosis. On a cellular level, K2P channels can have both proapoptotic and antiapoptotic effects, either promoting neurodegeneration or protecting neurons from ischemic cell death. TASK1 and TREK1 channels have a neuroprotective effect on stroke development, whereas TASK2 channels have a detrimental effect on neuronal survival under ischemic conditions. Future research in preclinical models is needed to provide a more detailed understanding of the contribution of K2P channel family members to neurologic disorders, before translation to the clinic is an option.
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Affiliation(s)
- Petra Ehling
- Department of Neurology, University of Münster, Münster, Germany,
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13
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Kawahara M, Mizuno D. Crosstalk between metals and neurodegenerative diseases. Nihon Eiseigaku Zasshi 2014; 69:155-65. [PMID: 25253517 DOI: 10.1265/jjh.69.155] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Trace elements including iron, zinc, copper, and manganese play essential roles in the maintenance of brain functions. Accumulating evidence suggests that dyshomeostasis of trace elements is implicated in the pathogenesis of neurodegenerative diseases including Alzheimer's disease, vascular type of dementia, prion diseases, and dementia with Lewy bodies. These diseases share similarity in the formation of β-sheets containing amyloid fibrils from disease-associated proteins, including the β-amyloid protein (AβP), the prion protein, α-synuclein, and polyglutamine, and the introduction of apoptotic degeneration. Trace elements can bind to these proteins and cause their conformational changes. Furthermore, these proteins reportedly play crucial roles in the regulation of trace elements. Considering that these proteins colocalize in synapses, it is possible that the interactions between the disease-associated proteins and trace elements are based on the physiological roles of these proteins. We review here the current understanding of the pathology of neurodegenerative diseases based on metal binding to disease-associated proteins and on the disruption of metal homeostasis.
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Affiliation(s)
- Masahiro Kawahara
- Department of Bio-Analytical Chemistry, Faculty of Pharmacy, Musashino University
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14
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Zhao Y, Pan R, Li S, Luo Y, Yan F, Yin J, Qi Z, Yan Y, Ji X, Liu KJ. Chelating intracellularly accumulated zinc decreased ischemic brain injury through reducing neuronal apoptotic death. Stroke 2014; 45:1139-47. [PMID: 24643405 DOI: 10.1161/strokeaha.113.004296] [Citation(s) in RCA: 57] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
BACKGROUND AND PURPOSE Zinc has been reported to possess both neurotoxic and neuroprotective capabilities. The effects of elevated intracellular zinc accumulation following transient focal cerebral ischemia remain to be fully elucidated. Here, we investigated whether removing zinc with the membrane-permeable zinc chelator, N,N,N',N'-tetrakis(2-pyridylmethyl)ethylenediamine (TPEN), would decrease the intracellular levels of zinc in the ischemic tissue, leading to reduced brain damage and improved neurological outcomes. METHODS Rats were pretreated with TPEN or vehicle before or after a 90-minute middle cerebral artery occlusion. Cerebral infarct volume, neurological functions, neuronal apoptosis, poly(ADP-ribose) polymerase activity, and cytosolic labile zinc were assessed after ischemia and reperfusion. RESULTS Cerebral ischemia caused a dramatic cytosolic labile zinc accumulation in the ischemic tissue, which was decreased markedly by TPEN (15 mg/kg) pretreatment. Chelating zinc lead to reduced infarct volume compared with vehicle-treated middle cerebral artery occlusion rats, accompanied by much improved neurological assessment and motor function, which were sustained for 14 days after reperfusion. We also determined that reducing zinc accumulation rescued neurons from ischemia-induced apoptotic death by reducing poly(ADP-ribose) polymerase-1 activation. CONCLUSIONS Ischemia-induced high accumulation of intracellular zinc significantly contributed to ischemic brain damage through promotion of neuronal apoptotic death. Removing zinc may be an effective and novel approach to reduce ischemic brain injury.
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Affiliation(s)
- Yongmei Zhao
- From the Cerebrovascular Diseases Research Institute, Xuanwu Hospital of Capital Medical University, Beijing, China (Y.Z., S.L., Y.L., F.Y., J.Y., Z.Q., Y.Y., X.J.); Beijing Geriatric Medical Research Center, Beijing, China (Y.Z., S.L., Y.L., F.Y., Z.Q., Y.Y., X.J.); Key Laboratory of Neurodegenerative Diseases, Ministry of Education, Beijing, China (Y.Z., Y.L., F.Y., J.Y., Z.Q., X.J.); Beijing Key Laboratory of Translational Medicine for Cerebrovascular Diseases, Beijing, China (Y.Z., Y.L., F.Y., J.Y., Z.Q., X.J.); and Department of Pharmaceutical Sciences, University of New Mexico, Albuquerque (R.P., K.J.L.)
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15
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Aiba I, Shuttleworth CW. Hypoxia limits inhibitory effects of Zn2+ on spreading depolarizations. PLoS One 2013; 8:e75739. [PMID: 24278106 PMCID: PMC3838375 DOI: 10.1371/journal.pone.0075739] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2013] [Accepted: 08/16/2013] [Indexed: 01/15/2023] Open
Abstract
Spreading depolarizations (SDs) are coordinated depolarizations of brain tissue that have been well-characterized in animal models and more recently implicated in the progression of stroke injury. We previously showed that extracellular Zn(2+) accumulation can inhibit the propagation of SD events. In that prior work, Zn(2+) was tested in normoxic conditions, where SD was generated by localized KCl pulses in oxygenated tissue. The current study examined the extent to which Zn(2+) effects are modified by hypoxia, to assess potential implications for stroke studies. The present studies examined SD generated in brain slices acutely prepared from mice, and recordings were made from the hippocampal CA1 region. SDs were generated by either local potassium injection (K-SD), exposure to the Na(+)/K(+)-ATPase inhibitor ouabain (ouabain-SD) or superfusion with modified ACSF with reduced oxygen and glucose concentrations (oxygen glucose deprivation: OGD-SD). Extracellular Zn(2+) exposures (100 µM ZnCl2) effectively decreased SD propagation rates and significantly increased the initiation threshold for K-SD generated in oxygenated ACSF (95% O2). In contrast, ZnCl2 did not inhibit propagation of OGD-SD or ouabain-SD generated in hypoxic conditions. Zn(2+) sensitivity in 0% O2 was restored by exposure to the protein oxidizer DTNB, suggesting that redox modulation may contribute to resistance to Zn(2+) in hypoxic conditions. DTNB pretreatment also significantly potentiated the inhibitory effects of competitive (D-AP5) or allosteric (Ro25-6981) NMDA receptor antagonists on OGD-SD. Finally, Zn(2+) inhibition of isolated NMDAR currents was potentiated by DTNB. Together, these results suggest that hypoxia-induced redox modulation can influence the sensitivity of SD to Zn(2+) as well as to other NMDAR antagonists. Such a mechanism may limit inhibitory effects of endogenous Zn(2+) accumulation in hypoxic regions close to ischemic infarcts.
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Affiliation(s)
- Isamu Aiba
- Department of Neurosciences, University of New Mexico, Albuquerque, New Mexico, United States of America
| | - C. William Shuttleworth
- Department of Neurosciences, University of New Mexico, Albuquerque, New Mexico, United States of America
- * E-mail:
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16
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Segawa S, Nishiura T, Furuta T, Ohsato Y, Tani M, Nishida K, Nagasawa K. Zinc is released by cultured astrocytes as a gliotransmitter under hypoosmotic stress-loaded conditions and regulates microglial activity. Life Sci 2013; 94:137-44. [PMID: 24252316 DOI: 10.1016/j.lfs.2013.11.007] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2013] [Revised: 10/22/2013] [Accepted: 11/07/2013] [Indexed: 12/26/2022]
Abstract
AIM Astrocytes contribute to the maintenance of brain homeostasis via the release of gliotransmitters such as ATP and glutamate. Here we examined whether zinc was released from astrocytes under stress-loaded conditions, and was involved in the regulation of microglial activity as a gliotransmitter. MAIN METHODS Hypoosmotic stress was loaded to astrocytes using balanced salt solution prepared to 214-314 mOsmol/L, and then intra- and extra-cellular zinc levels were assessed using Newport Green DCF diacetate (NG) and ICP-MS, respectively. Microglial activation by the astrocytic supernatant was assessed by their morphological changes and poly(ADP-ribose) (PAR) polymer accumulation. KEY FINDINGS Exposure of astrocytes to hypoosmotic buffer, increased the extracellular ATP level in osmolarity-dependent manners, indicating a load of hypoosmotic stress. In hypoosmotic stress-loaded astrocytes, there were apparent increases in the intra- and extra-cellular zinc levels. Incubation of microglia in the astrocytic conditioned medium transformed them into the activated "amoeboid" form and induced PAR formation. Administration of an extracellular zinc chelator, CaEDTA, to the astrocytic conditioned medium almost completely prevented the microglial activation. Treatment of astrocytes with an intracellular zinc chelator, TPEN, suppressed the hypoosmotic stress-increased intracellular, but not the extracellular, zinc level, and the increase in the intracellular zinc level was blocked partially by a nitric oxide synthase inhibitor, but not by CaEDTA, indicating that the mechanisms underlying the increases in the intra- and extra-cellular zinc levels might be different. SIGNIFICANCE These findings suggest that under hypoosmotic stress-loaded conditions, zinc is released from astrocytes and then plays a primary role in microglial activation as a gliotransmitter.
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Affiliation(s)
- Shohei Segawa
- Department of Environmental Biochemistry, Kyoto Pharmaceutical University, 5 Nakauchi-cho, Misasagi, Yamashina-ku, Kyoto 607-8414, Japan
| | - Takeshi Nishiura
- Department of Environmental Biochemistry, Kyoto Pharmaceutical University, 5 Nakauchi-cho, Misasagi, Yamashina-ku, Kyoto 607-8414, Japan
| | - Takahiro Furuta
- Department of Environmental Biochemistry, Kyoto Pharmaceutical University, 5 Nakauchi-cho, Misasagi, Yamashina-ku, Kyoto 607-8414, Japan
| | - Yuki Ohsato
- Department of Environmental Biochemistry, Kyoto Pharmaceutical University, 5 Nakauchi-cho, Misasagi, Yamashina-ku, Kyoto 607-8414, Japan
| | - Misaki Tani
- Department of Environmental Biochemistry, Kyoto Pharmaceutical University, 5 Nakauchi-cho, Misasagi, Yamashina-ku, Kyoto 607-8414, Japan
| | - Kentaro Nishida
- Department of Environmental Biochemistry, Kyoto Pharmaceutical University, 5 Nakauchi-cho, Misasagi, Yamashina-ku, Kyoto 607-8414, Japan
| | - Kazuki Nagasawa
- Department of Environmental Biochemistry, Kyoto Pharmaceutical University, 5 Nakauchi-cho, Misasagi, Yamashina-ku, Kyoto 607-8414, Japan.
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17
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Shuttleworth CW, Weiss JH. Zinc: new clues to diverse roles in brain ischemia. Trends Pharmacol Sci 2011; 32:480-6. [PMID: 21621864 DOI: 10.1016/j.tips.2011.04.001] [Citation(s) in RCA: 132] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2011] [Revised: 04/19/2011] [Accepted: 04/21/2011] [Indexed: 12/22/2022]
Abstract
Cerebral ischemia is a leading cause of morbidity and mortality, reflecting the extraordinary sensitivity of the brain to a brief loss of blood flow. A significant goal has been to identify pathways of neuronal injury that are selectively activated after stroke and may be amenable to drug therapy. An important advance was made nearly 25 years ago when Ca(2+) overload was implicated as a critical link between glutamate excitotoxicity and ischemic neurodegeneration. However, early hope for effective therapies faded as glutamate-targeted trials repeatedly failed to demonstrate efficacy in humans. In a review in 2000 in this journal, we described new evidence linking a related cation, zinc (Zn(2+)), to neuronal injury, emphasizing sources and mechanisms of Zn(2+) toxicity. The current review highlights progress over the last decade, emphasizing mechanisms through which Zn(2+) ions (from multiple sources) participate together with Ca(2+) in different stages of cascades of ischemic injury.
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Affiliation(s)
- C William Shuttleworth
- Department of Neurosciences, University of New Mexico School of Medicine, Albuquerque NM 87131, USA
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18
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Carter RE, Aiba I, Dietz RM, Sheline CT, Shuttleworth CW. Spreading depression and related events are significant sources of neuronal Zn2+ release and accumulation. J Cereb Blood Flow Metab 2011; 31:1073-84. [PMID: 20978516 PMCID: PMC3070966 DOI: 10.1038/jcbfm.2010.183] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/10/2010] [Revised: 08/27/2010] [Accepted: 09/11/2010] [Indexed: 11/09/2022]
Abstract
Spreading depression (SD) involves coordinated depolarizations of neurons and glia that propagate through the brain tissue. Repetitive SD-like events are common following human ischemic strokes, and are believed to contribute to the enlargement of infarct volume. Accumulation of Zn(2+) is also implicated in ischemic neuronal injury. Synaptic glutamate release contributes to SD propagation, and because Zn(2+) is costored with glutamate in some synaptic vesicles, we examined whether Zn(2+) is released by SD and may therefore provide a significant source of Zn(2+) in the postischemic period. Spreading depression-like events were generated in acutely prepared murine hippocampal slices by deprivation of oxygen and glucose (OGD), and Zn(2+) release was detected extracellularly by a Zn(2+)-selective indicator FluoZin-3. Deprivation of oxygen and glucose-SD produced large FluoZin-3 increases that propagated with the event, and signals were abolished in tissues from ZnT3 knockout animals lacking synaptic Zn(2+). Synaptic Zn(2+) release was also maintained with repetitive SDs generated by microinjections of KCl under normoxic conditions. Intracellular Zn(2+) accumulation in CA1 neurons, assessed using microinjection of FluoZin-3, showed significant increases following SD that was attributed to synaptic Zn(2+) release. These results suggest that Zn(2+) is released during SDs and could provide a significant source of Zn(2+) that contributes to neurodegeneration in the postischemic period.
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Affiliation(s)
- Russell E Carter
- Department of Neurosciences University of New Mexico, Albuquerque, New Mexico, USA
| | - Isamu Aiba
- Department of Neurosciences University of New Mexico, Albuquerque, New Mexico, USA
| | - Robert M Dietz
- Department of Neurosciences University of New Mexico, Albuquerque, New Mexico, USA
| | - Christian T Sheline
- LSU Health Sciences Center, Department of Ophthalmology and the Neuroscience Center of Excellence, New Orleans, Louisiana, USA
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19
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Chang CY, Ou YC, Kao TK, Pan HC, Lin SY, Liao SL, Wang WY, Lu HC, Chen CJ. Glucose exacerbates zinc-induced astrocyte death. Toxicol Lett 2010; 199:102-9. [DOI: 10.1016/j.toxlet.2010.08.012] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2010] [Revised: 08/16/2010] [Accepted: 08/20/2010] [Indexed: 01/04/2023]
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20
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Su CK, Sun YC, Tzeng SF, Yang CS, Wang CY, Yang MH. In vivo monitoring of the transfer kinetics of trace elements in animal brains with hyphenated inductively coupled plasma mass spectrometry techniques. MASS SPECTROMETRY REVIEWS 2010; 29:392-424. [PMID: 19437493 DOI: 10.1002/mas.20240] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
The roles of metal ions to sustain normal function and to cause dysfunction of neurological systems have been confirmed by various studies. However, because of the lack of adequate analytical method to monitor the transfer kinetics of metal ions in the brain of a living animal, research on the physiopathological roles of metal ions in the CNS remains in its early stages and more analytical efforts are still needed. To explicitly model the possible links between metal ions and physiopathological alterations, it is essential to develop in vivo monitoring techniques that can bridge the gap between metalloneurochemistry and neurophysiopathology. Although inductively coupled plasma mass spectrometry (ICP-MS) is a very powerful technique for multiple trace element analyses, when dealing with chemically complex microdialysis samples, the detection capability is largely limited by instrumental sensitivity, selectivity, and contamination that arise from the experimental procedure. As a result, in recent years several high efficient and clean on-line sample pretreatment systems have been developed and combined with microdialysis and ICP-MS for the continuous and in vivo determination of the concentration-time profiles of metal ions in the extracellular space of rat brain. This article reviews the research relevant to the development of analytical techniques for the in vivo determination of dynamic variation in the concentration levels of metal ions in a living animal.
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Affiliation(s)
- Cheng-Kuan Su
- Department of Biomedical Engineering and Environmental Sciences, National Tsing Hua University, Hsinchu, Taiwan
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21
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Inoue K, Branigan D, Xiong ZG. Zinc-induced neurotoxicity mediated by transient receptor potential melastatin 7 channels. J Biol Chem 2010; 285:7430-9. [PMID: 20048154 PMCID: PMC2844191 DOI: 10.1074/jbc.m109.040485] [Citation(s) in RCA: 114] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2009] [Revised: 12/24/2009] [Indexed: 01/17/2023] Open
Abstract
Transient receptor potential melastatin 7 (TRPM7) channels are novel Ca(2+)-permeable non-selective cation channels ubiquitously expressed. Activation of TRPM7 channels has been shown to be involved in cellular Mg(2+) homeostasis, diseases caused by abnormal magnesium absorption, and in Ca(2+)-mediated neuronal injury under ischemic conditions. Here we show strong evidence suggesting that TRPM7 channels also play an important role in cellular Zn(2+) homeostasis and in Zn(2+)-mediated neuronal injury. Using a combination of fluorescent Zn(2+) imaging, small interfering RNA, pharmacological analysis, and cell injury assays, we show that activation of TRPM7 channels augmented Zn(2+)-induced injury of cultured mouse cortical neurons. The Zn(2+)-mediated neurotoxicity was inhibited by nonspecific TRPM7 blockers Gd(3+) or 2-aminoethoxydiphenyl borate, and by knockdown of TRPM7 channels with small interfering RNA. In addition, Zn(2+)-mediated neuronal injury under oxygen-glucose deprivation conditions was also diminished by silencing TRPM7. Furthermore, we show that overexpression of TRPM7 channels in HEK293 cells increased intracellular Zn(2+) accumulation and Zn(2+)-induced cell injury, while silencing TRPM7 by small interfering RNA attenuated the Zn(2+)-mediated cell toxicity. Thus, TRPM7 channels may represent a novel target for neurological disorders where Zn(2+) toxicity plays an important role.
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Affiliation(s)
- Koichi Inoue
- From the Robert S. Dow Neurobiology Laboratories, Legacy Research, Portland, Oregon 97232
| | - Deborah Branigan
- From the Robert S. Dow Neurobiology Laboratories, Legacy Research, Portland, Oregon 97232
| | - Zhi-Gang Xiong
- From the Robert S. Dow Neurobiology Laboratories, Legacy Research, Portland, Oregon 97232
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22
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Abstract
Zinc is a life-sustaining trace element, serving structural, catalytic, and regulatory roles in cellular biology. It is required for normal mammalian brain development and physiology, such that deficiency or excess of zinc has been shown to contribute to alterations in behavior, abnormal central nervous system development, and neurological disease. In this light, it is not surprising that zinc ions have now been shown to play a role in the neuromodulation of synaptic transmission as well as in cortical plasticity. Zinc is stored in specific synaptic vesicles by a class of glutamatergic or "gluzinergic" neurons and is released in an activity-dependent manner. Because gluzinergic neurons are found almost exclusively in the cerebral cortex and limbic structures, zinc may be critical for normal cognitive and emotional functioning. Conversely, direct evidence shows that zinc might be a relatively potent neurotoxin. Neuronal injury secondary to in vivo zinc mobilization and release occurs in several neurological disorders such as Alzheimer's disease and amyotrophic lateral sclerosis, in addition to epilepsy and ischemia. Thus, zinc homeostasis is integral to normal central nervous system functioning, and in fact its role may be underappreciated. This article provides an overview of zinc neurobiology and reviews the experimental evidence that implicates zinc signals in the pathophysiology of neuropsychiatric diseases. A greater understanding of zinc's role in the central nervous system may therefore allow for the development of therapeutic approaches where aberrant metal homeostasis is implicated in disease pathogenesis.
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Affiliation(s)
- Byron K Y Bitanihirwe
- Laboratory of Behavioral Neurobiology, Swiss Federal Institute of Technology, Zurich, Switzerland
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23
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Aguilar-Alonso P, Martinez-Fong D, Pazos-Salazar NG, Brambila E, Gonzalez-Barrios JA, Mejorada A, Flores G, Millan-Perezpeña L, Rubio H, Leon-Chavez BA. The increase in zinc levels and upregulation of zinc transporters are mediated by nitric oxide in the cerebral cortex after transient ischemia in the rat. Brain Res 2008; 1200:89-98. [PMID: 18289514 DOI: 10.1016/j.brainres.2007.11.077] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2007] [Revised: 11/13/2007] [Accepted: 11/15/2007] [Indexed: 11/19/2022]
Abstract
The transient occlusion of cerebral arteries causes an increase in zinc levels in the brain, which is associated with a production of nitric oxide (NO). The types of zinc transporters (ZnT) involved in zinc homeostasis in the cerebral cortex after hypoxia-ischemia are not completely known. We studied the effect of the transient occlusion (10 min) of the common carotid artery (CCA) on NO-induced zinc levels, ZnT mRNA expression, and cell-death markers in the cerebral cortex-hippocampus of the rat. Nitrites, zinc, and lipoperoxidation were quantified by colorimetric methods, ZnT expression was determined by RT-PCR, caspase-3 by ELISA and immunohistochemistry, and histopathological alterations by H&E staining. After restoration of the blood flow, the basal levels of NO and zinc increased in a biphasic manner over time, but the peaks of NO levels appeared earlier (2 h and 24 h) than those of zinc (6 h and 36 h). Upregulation of ZnT1, ZnT2, and ZnT4 mRNAs was determined after 8-h postreperfusion, but ZnT3 RNA levels were unaffected. Lipoperoxidation and caspase-3 levels were also increased, and necrosis and apoptosis were present at 24 h postreperfusion. All the effects determined were prevented by l-nitro-arginine methyl ester injected 1 h before the occlusion of the CCA. Our results suggest that the upregulation of ZnT1, ZnT2, and ZnT4 was to decrease the cytosolic zinc levels caused by NO after transient occlusion of the CCA, although this was unable to lead to physiological levels of zinc and to prevent cell damage in the cerebral cortex-hippocampus of the rat.
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Affiliation(s)
- Patricia Aguilar-Alonso
- Area de Bioquímica y Biología Molecular, Facultad de Ciencias químicas, BUAP. 14 sur y Av. San Claudio, 72570, Puebla, Pue. México
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24
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Galasso SL, Dyck RH. The role of zinc in cerebral ischemia. MOLECULAR MEDICINE (CAMBRIDGE, MASS.) 2007; 13:380-7. [PMID: 17622314 PMCID: PMC1952671 DOI: 10.2119/2007–00044.galasso] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Received: 04/23/2007] [Accepted: 04/25/2007] [Indexed: 11/06/2022]
Abstract
Ischemic stroke is one of the most pervasive life-threatening neurological conditions for which there currently exists limited therapeutic intervention beyond prevention. As calcium-focused neuroprotective strategies have met with limited clinical success, it is imperative that alternative therapeutic targets be considered in the attempt to antagonize ischemic-mediated injury. As such, zinc, which is able to function both as a signaling mediator and neurotoxin, has been implicated in cerebral ischemia. While zinc was first purported to have a role in cerebral ischemia nearly twenty years ago, our understanding of how zinc mediates ischemic injury is still in its relative infancy. Within this review, we examine some of the studies by which zinc has exerted either neuroprotective or neurotoxic effects during global and focal cerebral ischemia.
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Affiliation(s)
- Sherri L Galasso
- Department of Psychology, University of Calgary, Calgary, Alberta, Canada
- Hotchkiss Brain Institute, University of Calgary, Calgary, Alberta, Canada
| | - Richard H Dyck
- Department of Psychology, University of Calgary, Calgary, Alberta, Canada
- Department of Cell Biology and Anatomy, University of Calgary, Calgary, Alberta, Canada
- Hotchkiss Brain Institute, University of Calgary, Calgary, Alberta, Canada
- Address correspondence and reprint requests to Richard H Dyck, Department of Psychology, University of Calgary, 2500 University Drive N.W. Calgary, Alberta T2N 1N4. Phone: 403-220-4206; Fax: 403-282-8249;
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25
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Abstract
Ischemic stroke is one of the most pervasive life-threatening neurological conditions for which there currently exists limited therapeutic intervention beyond prevention. As calcium-focused neuroprotective strategies have met with limited clinical success, it is imperative that alternative therapeutic targets be considered in the attempt to antagonize ischemic-mediated injury. As such, zinc, which is able to function both as a signaling mediator and neurotoxin, has been implicated in cerebral ischemia. While zinc was first purported to have a role in cerebral ischemia nearly twenty years ago, our understanding of how zinc mediates ischemic injury is still in its relative infancy. Within this review, we examine some of the studies by which zinc has exerted either neuroprotective or neurotoxic effects during global and focal cerebral ischemia.
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Affiliation(s)
- Sherri L Galasso
- Department of Psychology, University of Calgary, Calgary, Alberta, Canada
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