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Roy S, Lutsenko S. Mechanism of Cu entry into the brain: many unanswered questions. Neural Regen Res 2024; 19:2421-2429. [PMID: 38526278 PMCID: PMC11090436 DOI: 10.4103/1673-5374.393107] [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: 08/06/2023] [Revised: 11/10/2023] [Accepted: 12/09/2023] [Indexed: 03/26/2024] Open
Abstract
Brain tissue requires high amounts of copper (Cu) for its key physiological processes, such as energy production, neurotransmitter synthesis, maturation of neuropeptides, myelination, synaptic plasticity, and radical scavenging. The requirements for Cu in the brain vary depending on specific brain regions, cell types, organism age, and nutritional status. Cu imbalances cause or contribute to several life-threatening neurologic disorders including Menkes disease, Wilson disease, Alzheimer's disease, Parkinson's disease, and others. Despite the well-established role of Cu homeostasis in brain development and function, the mechanisms that govern Cu delivery to the brain are not well defined. This review summarizes available information on Cu transfer through the brain barriers and discusses issues that require further research.
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Affiliation(s)
- Shubhrajit Roy
- Department of Physiology, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Svetlana Lutsenko
- Department of Physiology, Johns Hopkins University School of Medicine, Baltimore, MD, USA
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Shirai T, Takase D, Yokoyama J, Nakanishi K, Uehara C, Saito N, Kato-Namba A, Yoshikawa K. Functions of human olfactory mucus and age-dependent changes. Sci Rep 2023; 13:971. [PMID: 36653421 PMCID: PMC9846672 DOI: 10.1038/s41598-023-27937-1] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2022] [Accepted: 01/10/2023] [Indexed: 01/19/2023] Open
Abstract
Odorants are detected by olfactory sensory neurons, which are covered by olfactory mucus. Despite the existence of studies on olfactory mucus, its constituents, functions, and interindividual variability remain poorly understood. Here, we describe a human study that combined the collection of olfactory mucus and olfactory psychophysical tests. Our analyses revealed that olfactory mucus contains high concentrations of solutes, such as total proteins, inorganic elements, and molecules for xenobiotic metabolism. The high concentrations result in a capacity to capture or metabolize a specific repertoire of odorants. We provide evidence that odorant metabolism modifies our sense of smell. Finally, the amount of olfactory mucus decreases in an age-dependent manner. A follow-up experiment recapitulated the importance of the amount of mucus in the sensitive detection of odorants by their receptors. These findings provide a comprehensive picture of the molecular processes in olfactory mucus and propose a potential cause of olfactory decline.
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Affiliation(s)
- Tomohiro Shirai
- Sensory Science Research, Kao Corporation, 2606 Akabane, Ichikai-machi, Haga, Tochigi, Japan
| | - Dan Takase
- Sensory Science Research, Kao Corporation, 2606 Akabane, Ichikai-machi, Haga, Tochigi, Japan
| | - Junkichi Yokoyama
- Department of Otolaryngology-Head and Neck Surgery, Edogawa Hospital, 2-24-18 Higashikoiwa, Edogawa, Tokyo, Japan.,Department of Otolaryngology-Head and Neck Surgery, Nadogaya Hospital, 2-1-1 Shinkashiwa, Kashiwa, Chiba, Japan
| | - Kuniyuki Nakanishi
- Analytical Science Research, Kao Corporation, 1334 Minato, Wakayama, Wakayama, Japan
| | - Chisaki Uehara
- Sensory Science Research, Kao Corporation, 2606 Akabane, Ichikai-machi, Haga, Tochigi, Japan
| | - Naoko Saito
- Sensory Science Research, Kao Corporation, 2606 Akabane, Ichikai-machi, Haga, Tochigi, Japan
| | - Aya Kato-Namba
- Sensory Science Research, Kao Corporation, 2606 Akabane, Ichikai-machi, Haga, Tochigi, Japan
| | - Keiichi Yoshikawa
- Sensory Science Research, Kao Corporation, 2606 Akabane, Ichikai-machi, Haga, Tochigi, Japan.
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Zhang S, Zhang L, Lu H, Yao Y, Liu X, Hou J. A cuproptosis and copper metabolism–related gene prognostic index for head and neck squamous cell carcinoma. Front Oncol 2022; 12:955336. [PMID: 36072790 PMCID: PMC9441563 DOI: 10.3389/fonc.2022.955336] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2022] [Accepted: 08/01/2022] [Indexed: 11/13/2022] Open
Abstract
BackgroundThe purpose of this study was to identify the prognostic value of cuproptosis and copper metabolism–related genes, to clarify their molecular and immunological characteristics, and to elucidate their benefits in head and neck squamous cell carcinoma (HNSCC).MethodsThe details of human cuproptosis and copper metabolism–related genes were searched and filtered from the msigdb database and the latest literature. To identify prognostic genes associated with cuproptosis and copper metabolism, we used least absolute shrinkage and selection operator regression, and this coefficient was used to set up a prognostic risk score model. HNSCC samples were divided into two groups according to the median risk. Afterwards, the function and immune characteristics of these genes in HNSCC were analyzed.ResultsThe 14-gene signature was constructed to classify HNSCC patients into low-risk and high-risk groups according to the risk level. In the The Cancer Genome Atlas (TCGA) cohort, the overall survival (OS) rate of the high-risk group was lower than that of the low-risk group (P < 0.0001). The area under the curve of the time-dependent Receiver Operator Characteristic (ROC) curve assessed the good performance of the genetic signature in predicting OS and showed similar performance in the external validation cohort. Gene Ontology and Kyoto Encyclopedia of Genes and Genomes enrichment assays and Protein-Protein Interaction (PPI) protein networks have been used to explore signaling pathways and potential mechanisms that were markedly active in patients with HNSCC. Furthermore, the 14 cuproptosis and copper metabolism-related genes were significantly correlated with the immune microenvironment, suggesting that these genes may be linked with the immune regulation and development of HNSCC.ConclusionsOur results emphasize the significance of cuproptosis and copper metabolism as a predictive biomarker for HNSCC, and its expression levels seem to be correlated with immune- related features; thus, they may be a possible biomarker for HNSCC prognosis.
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Affiliation(s)
- Shuaiyuan Zhang
- Department of Oral and Maxillofacial Surgery, Guanghua School of Stomatology, Hospital of Stomatology, Sun Yat-sen University, Guangzhou, China
- Guangdong Provincial Key Laboratory of Stomatology, Sun Yat-sen University, Guangzhou, China
| | - Lujin Zhang
- Department of Oral and Maxillofacial Surgery, Guanghua School of Stomatology, Hospital of Stomatology, Sun Yat-sen University, Guangzhou, China
- Guangdong Provincial Key Laboratory of Stomatology, Sun Yat-sen University, Guangzhou, China
| | - Huanzi Lu
- Department of Oral and Maxillofacial Surgery, Guanghua School of Stomatology, Hospital of Stomatology, Sun Yat-sen University, Guangzhou, China
- Guangdong Provincial Key Laboratory of Stomatology, Sun Yat-sen University, Guangzhou, China
| | - Yihuan Yao
- Department of Oral and Maxillofacial Surgery, Guanghua School of Stomatology, Hospital of Stomatology, Sun Yat-sen University, Guangzhou, China
- Guangdong Provincial Key Laboratory of Stomatology, Sun Yat-sen University, Guangzhou, China
| | - Xiaoyong Liu
- Department of Oral and Maxillofacial Surgery, Guanghua School of Stomatology, Hospital of Stomatology, Sun Yat-sen University, Guangzhou, China
- Guangdong Provincial Key Laboratory of Stomatology, Sun Yat-sen University, Guangzhou, China
| | - Jingsong Hou
- Department of Oral and Maxillofacial Surgery, Guanghua School of Stomatology, Hospital of Stomatology, Sun Yat-sen University, Guangzhou, China
- Guangdong Provincial Key Laboratory of Stomatology, Sun Yat-sen University, Guangzhou, China
- *Correspondence: Jingsong Hou,
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Abstract
The Anthropocene Epoch poses a critical challenge for organisms: they must cope with new threats at a rapid rate. These threats include toxic chemical compounds released into the environment by human activities. Here, we examine elevated concentrations of heavy metal ions as an example of anthropogenic stressors. We find that the fruit fly Drosophila avoids nine metal ions when present at elevated concentrations that the flies experienced rarely, if ever, until the Anthropocene. We characterize the avoidance of feeding and egg laying on metal ions, and we identify receptors, neurons, and taste organs that contribute to this avoidance. Different subsets of taste receptors, including members of both Ir (Ionotropic receptor) and Gr (Gustatory receptor) families contribute to the avoidance of different metal ions. We find that metal ions activate certain bitter-sensing neurons and inhibit sugar-sensing neurons. Some behavioral responses are mediated largely through neurons of the pharynx. Feeding avoidance remains stable over 10 generations of exposure to copper and zinc ions. Some responses to metal ions are conserved across diverse dipteran species, including the mosquito Aedes albopictus. Our results suggest mechanisms that may be essential to insects as they face challenges from environmental changes in the Anthropocene.
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Wessels I, Rolles B, Slusarenko AJ, Rink L. Zinc deficiency as a possible risk factor for increased susceptibility and severe progression of Corona Virus Disease 19. Br J Nutr 2022; 127:214-232. [PMID: 33641685 PMCID: PMC8047403 DOI: 10.1017/s0007114521000738] [Citation(s) in RCA: 27] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2020] [Revised: 01/07/2021] [Accepted: 02/21/2021] [Indexed: 01/08/2023]
Abstract
The importance of Zn for human health becomes obvious during Zn deficiency. Even mild insufficiencies of Zn cause alterations in haematopoiesis and immune functions, resulting in a proinflammatory phenotype and a disturbed redox metabolism. Although immune system malfunction has the most obvious effect, the functions of several tissue cell types are disturbed if Zn supply is limiting. Adhesion molecules and tight junction proteins decrease, while cell death increases, generating barrier dysfunction and possibly organ failure. Taken together, Zn deficiency both weakens the resistance of the human body towards pathogens and at the same time increases the danger of an overactive immune response that may cause tissue damage. The case numbers of Corona Virus Disease 19 (COVID-19) are still increasing, which is causing enormous problems for health systems and economies. There is an urgent need to reduce both the number of severe cases and the resulting deaths. While therapeutic options are still under investigation, and first vaccines have been approved, cost-effective ways to reduce the likelihood of or even prevent infection, and the transition from mild symptoms to more serious detrimental disease, are highly desirable. Nutritional supplementation might be an effective option to achieve these aims. In this review, we discuss known Zn deficiency effects in the context of an infection with Severe Acute Respiratory Syndrome-Coronavirus-2 and its currently known pathogenic mechanisms and elaborate on how severe pre-existing Zn deficiency may pre-dispose patients to a severe progression of COVID-19. First published clinical data on the association of Zn homoeostasis with COVID-19 and registered studies in progress are listed.
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Affiliation(s)
- Inga Wessels
- Institute of Immunology, Faculty of Medicine, RWTH Aachen University Hospital, Pauwelsstr. 30, 52074Aachen, Germany
| | - Benjamin Rolles
- Department of Hematology, Oncology, Hemostaseology and Stem Cell Transplantation, Faculty of Medicine, RWTH Aachen University Hospital, Pauwelsstrasse 30, 52074Aachen, Germany
| | - Alan J. Slusarenko
- Department of Plant Physiology, RWTH Aachen University, Worringer Weg 1, 52074Aachen, Germany
| | - Lothar Rink
- Institute of Immunology, Faculty of Medicine, RWTH Aachen University Hospital, Pauwelsstr. 30, 52074Aachen, Germany
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Adamson SXF, Zheng W, Agim ZS, Du S, Fleming S, Shannahan J, Cannon J. Systemic Copper Disorders Influence the Olfactory Function in Adult Rats: Roles of Altered Adult Neurogenesis and Neurochemical Imbalance. Biomolecules 2021; 11:1315. [PMID: 34572528 PMCID: PMC8471899 DOI: 10.3390/biom11091315] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2021] [Revised: 08/29/2021] [Accepted: 08/30/2021] [Indexed: 12/18/2022] Open
Abstract
Disrupted systemic copper (Cu) homeostasis underlies neurodegenerative diseases with early symptoms including olfactory dysfunction. This study investigated the impact of Cu dyshomeostasis on olfactory function, adult neurogenesis, and neurochemical balance. Models of Cu deficiency (CuD) and Cu overload (CuO) were established by feeding adult rats with Cu-restricted diets plus ip. injection of a Cu chelator (ammonium tetrathiomolybdate) and excess Cu, respectively. CuD reduced Cu levels in the olfactory bulb (OB), subventricular zone (SVZ), rostral migratory stream (RMS), and striatum, while CuO increased Cu levels in these areas. The buried pellet test revealed both CuD and CuO prolonged the latency to uncover food. CuD increased neural proliferation and stem cells in the SVZ and newly differentiated neurons in the OB, whereas CuO caused opposite alterations, suggesting a "switch"-type function of Cu in regulating adult neurogenesis. CuO increased GABA in the OB, while both CuD and CuO reduced DOPAC, HVA, 5-HT and the DA turnover rate in olfactory-associated brain regions. Altered mRNA expression of Cu transport and storage proteins in tested brain areas were observed under both conditions. Together, results support an association between systemic Cu dyshomeostasis and olfactory dysfunction. Specifically, altered adult neurogenesis along the SVZ-RMS-OB pathway and neurochemical imbalance could be the factors that may contribute to olfactory dysfunction.
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Affiliation(s)
- Sherleen Xue-Fu Adamson
- School of Health Sciences, Purdue University, West Lafayette, IN 47907, USA; (S.X.-F.A.); (Z.S.A.); (S.D.); (J.S.)
| | - Wei Zheng
- School of Health Sciences, Purdue University, West Lafayette, IN 47907, USA; (S.X.-F.A.); (Z.S.A.); (S.D.); (J.S.)
- Purdue Institute for Integrative Neurosciences, Purdue University, West Lafayette, IN 47907, USA
| | - Zeynep Sena Agim
- School of Health Sciences, Purdue University, West Lafayette, IN 47907, USA; (S.X.-F.A.); (Z.S.A.); (S.D.); (J.S.)
| | - Sarah Du
- School of Health Sciences, Purdue University, West Lafayette, IN 47907, USA; (S.X.-F.A.); (Z.S.A.); (S.D.); (J.S.)
| | - Sheila Fleming
- Department of Pharmaceutical Sciences, Northeast Ohio Medical University, Rootstown, OH 44272, USA;
| | - Jonathan Shannahan
- School of Health Sciences, Purdue University, West Lafayette, IN 47907, USA; (S.X.-F.A.); (Z.S.A.); (S.D.); (J.S.)
| | - Jason Cannon
- School of Health Sciences, Purdue University, West Lafayette, IN 47907, USA; (S.X.-F.A.); (Z.S.A.); (S.D.); (J.S.)
- Purdue Institute for Integrative Neurosciences, Purdue University, West Lafayette, IN 47907, USA
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Witt B, Stiboller M, Raschke S, Friese S, Ebert F, Schwerdtle T. Characterizing effects of excess copper levels in a human astrocytic cell line with focus on oxidative stress markers. J Trace Elem Med Biol 2021; 65:126711. [PMID: 33486291 DOI: 10.1016/j.jtemb.2021.126711] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/25/2020] [Revised: 12/02/2020] [Accepted: 01/02/2021] [Indexed: 12/17/2022]
Abstract
BACKGROUND Being an essential trace element, copper is involved in diverse physiological processes. However, excess levels might lead to adverse effects. Disrupted copper homeostasis, particularly in the brain, has been associated with human diseases including the neurodegenerative disorders Wilson and Alzheimer's disease. In this context, astrocytes play an important role in the regulation of the copper homeostasis in the brain and likely in the prevention against neuronal toxicity, consequently pointing them out as a potential target for the neurotoxicity of copper. Major toxic mechanisms are discussed to be directed against mitochondria probably via oxidative stress. However, the toxic potential and mode of action of copper in astrocytes is poorly understood, so far. METHODS In this study, excess copper levels affecting human astrocytic cell model and their involvement in the neurotoxic mode of action of copper, as well as, effects on the homeostasis of other trace elements (Mn, Fe, Ca and Mg) were investigated. RESULTS Copper induced substantial cytotoxic effects in the human astrocytic cell line following 48 h incubation (EC30: 250 μM) and affected mitochondrial function, as observed via reduction of mitochondrial membrane potential and increased ROS production, likely originating from mitochondria. Moreover, cellular GSH metabolism was altered as well. Interestingly, not only cellular copper levels were affected, but also the homeostasis of other elements (Ca, Fe and Mn) were disrupted. CONCLUSION One potential toxic mode of action of copper seems to be effects on the mitochondria along with induction of oxidative stress in the human astrocytic cell model. Moreover, excess copper levels seem to interact with the homeostasis of other essential elements such as Ca, Fe and Mn. Disrupted element homeostasis might also contribute to the induction of oxidative stress, likely involved in the onset and progression of neurodegenerative disorders. These insights in the toxic mechanisms will help to develop ideas and approaches for therapeutic strategies against copper-mediated diseases.
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Affiliation(s)
- Barbara Witt
- Institute of Nutritional Science, University of Potsdam, Arthur-Scheunert-Allee 114-116, 14558, Nuthetal, Germany.
| | - Michael Stiboller
- Institute of Nutritional Science, University of Potsdam, Arthur-Scheunert-Allee 114-116, 14558, Nuthetal, Germany
| | - Stefanie Raschke
- Institute of Nutritional Science, University of Potsdam, Arthur-Scheunert-Allee 114-116, 14558, Nuthetal, Germany
| | - Sharleen Friese
- Institute of Nutritional Science, University of Potsdam, Arthur-Scheunert-Allee 114-116, 14558, Nuthetal, Germany
| | - Franziska Ebert
- Institute of Nutritional Science, University of Potsdam, Arthur-Scheunert-Allee 114-116, 14558, Nuthetal, Germany
| | - Tanja Schwerdtle
- Institute of Nutritional Science, University of Potsdam, Arthur-Scheunert-Allee 114-116, 14558, Nuthetal, Germany; TraceAge - DFG Research Unit on Interactions of Essential Trace Elements in Healthy and Diseased Elderly (FOR 2558), Berlin-Potsdam-Jena, Germany; German Federal Institute for Risk Assessment (BfR), Max-Dohrn-Strasse 8-10, 10589, Berlin, Germany
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Endogenous zinc nanoparticles in the rat olfactory epithelium are functionally significant. Sci Rep 2020; 10:18435. [PMID: 33116197 PMCID: PMC7595131 DOI: 10.1038/s41598-020-75430-w] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2020] [Accepted: 10/13/2020] [Indexed: 11/29/2022] Open
Abstract
The role of zinc in neurobiology is rapidly expanding. Zinc is especially essential in olfactory neurobiology. Naturally occurring zinc nanoparticles were detected in olfactory and nasal respiratory epithelia and cilia in animals. The addition of these nanoparticles to a mixture of odorants, including ethyl butyrate, eugenol, and carvone, considerably increased the electrical responses of the olfactory sensory receptors. Studies of these nanoparticles by ransmission electron microscopy (TEM) and selected area electron diffraction revealed metal elemental crystalline zinc nanoparticles 2–4 nm in diameter. These particles did not contain oxidized zinc. The enhancement of the odorant responses induced by the endogenous zinc nanoparticles appears to be similar to the amplification produced by engineered zinc nanoparticles. Zinc nanoparticles produce no odor response but increase odor response if mixed with an odorant. These effects are dose-dependent and reversible. Some other metal nanoparticles, such as copper, silver, gold, and platinum, do not have the effects observed in the case of zinc nanoparticles. The olfactory enhancement was observed in young and mature mouse olfactory epithelium cultures, in the dissected olfactory epithelium of rodents, and in live conscious dogs. The physiological significance of the detected endogenous metal nanoparticles in an animal tissue has been demonstrated for the first time. Overall, our results may advance the understanding of the initial events in olfaction.
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Loviscach L, Backes TM, Langfermann DS, Ulrich M, Thiel G. Zn 2+ ions inhibit gene transcription following stimulation of the Ca 2+ channels Ca v1.2 and TRPM3. Metallomics 2020; 12:1735-1747. [PMID: 33030499 DOI: 10.1039/d0mt00180e] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Zinc, a trace element, is necessary for the correct structure and function of many proteins. Therefore, Zn2+ has to be taken up by the cells, using specific Zn2+ transporters or Ca2+ channels. In this study, we have focused on two Ca2+ channels, the L-type voltage-gated Cav1.2 channel and the transient receptor potential channel TRPM3. Stimulation of either channel induces an intracellular signaling cascade leading to the activation of the transcription factor AP-1. The influx of Ca2+ ions into the cytoplasm is essential for this activity. We asked whether extracellular Zn2+ ions affect Cav1.2 or TRPM3-induced gene transcription following stimulation of the channels. The results show that extracellular Zn2+ ions reduced the activation of AP-1 by more than 80% following stimulation of either voltage-gated Cav1.2 channels or TRPM3 channels. Experiments performed with cells maintained in Ca2+-free medium revealed that Zn2+ ions cannot replace Ca2+ ions in inducing gene transcription via stimulation of Cav1.2 and TRPM3 channels. Re-addition of Ca2+ ions to the cell culture medium, however, restored the ability of these Ca2+ channels to induce a signaling cascade leading to the activation of AP-1. Secretory cells, including neurons and pancreatic β-cells, release Zn2+ ions during exocytosis. We propose that the released Zn2+ ions function as a negative feedback loop for stimulus-induced exocytosis by inhibiting Ca2+ channel signaling.
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Affiliation(s)
- Louisa Loviscach
- Department of Medical Biochemistry and Molecular Biology, Saarland University Medical Faculty, D-66421 Homburg, Germany.
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Krzywoszyńska K, Witkowska D, Świątek-Kozłowska J, Szebesczyk A, Kozłowski H. General Aspects of Metal Ions as Signaling Agents in Health and Disease. Biomolecules 2020; 10:biom10101417. [PMID: 33036384 PMCID: PMC7600656 DOI: 10.3390/biom10101417] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2020] [Revised: 09/30/2020] [Accepted: 10/02/2020] [Indexed: 02/07/2023] Open
Abstract
This review focuses on the current knowledge on the involvement of metal ions in signaling processes within the cell, in both physiological and pathological conditions. The first section is devoted to the recent discoveries on magnesium and calcium-dependent signal transduction-the most recognized signaling agents among metals. The following sections then describe signaling pathways where zinc, copper, and iron play a key role. There are many systems in which changes in intra- and extra-cellular zinc and copper concentrations have been linked to important downstream events, especially in nervous signal transduction. Iron signaling is mostly related with its homeostasis. However, it is also involved in a recently discovered type of programmed cell death, ferroptosis. The important differences in metal ion signaling, and its disease-leading alterations, are also discussed.
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Affiliation(s)
- Karolina Krzywoszyńska
- Institute of Health Sciences, University of Opole, 68 Katowicka St., 45-060 Opole, Poland; (J.Ś.-K.); (A.S.); (H.K.)
- Correspondence: (K.K.); (D.W.); Tel.: +48-77-44-23-549 (K.K); +48-77-44-23-548 (D.W.)
| | - Danuta Witkowska
- Institute of Health Sciences, University of Opole, 68 Katowicka St., 45-060 Opole, Poland; (J.Ś.-K.); (A.S.); (H.K.)
- Correspondence: (K.K.); (D.W.); Tel.: +48-77-44-23-549 (K.K); +48-77-44-23-548 (D.W.)
| | - Jolanta Świątek-Kozłowska
- Institute of Health Sciences, University of Opole, 68 Katowicka St., 45-060 Opole, Poland; (J.Ś.-K.); (A.S.); (H.K.)
| | - Agnieszka Szebesczyk
- Institute of Health Sciences, University of Opole, 68 Katowicka St., 45-060 Opole, Poland; (J.Ś.-K.); (A.S.); (H.K.)
| | - Henryk Kozłowski
- Institute of Health Sciences, University of Opole, 68 Katowicka St., 45-060 Opole, Poland; (J.Ś.-K.); (A.S.); (H.K.)
- Faculty of Chemistry, University of Wrocław, 14 F. Joliot-Curie St., 50-383 Wrocław, Poland
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Bhattacharjee A, Ghosh S, Chatterji A, Chakraborty K. Neuron-glia: understanding cellular copper homeostasis, its cross-talk and their contribution towards neurodegenerative diseases. Metallomics 2020; 12:1897-1911. [PMID: 33295934 DOI: 10.1039/d0mt00168f] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Over the years, the mechanism of copper homeostasis in various organ systems has gained importance. This is owing to the involvement of copper in a wide range of genetic disorders, most of them involving neurological symptoms. This highlights the importance of copper and its tight regulation in a complex organ system like the brain. It demands understanding the mechanism of copper acquisition and delivery to various cell types overcoming the limitation imposed by the blood brain barrier. The present review aims to investigate the existing work to understand the mechanism and complexity of cellular copper homeostasis in the two major cell types of the CNS - the neurons and the astrocytes. It investigates the mechanism of copper uptake, incorporation and export by these cell types. Furthermore, it brings forth the common as well as the exclusive aspects of neuronal and glial copper homeostasis including the studies from copper-based sensors. Glia act as a mediator of copper supply between the endothelium and the neurons. They possess all the qualifications of acting as a 'copper-sponge' for supply to the neurons. The neurons, on the other hand, require copper for various essential functions like incorporation as a cofactor for enzymes, synaptogenesis, axonal extension, inhibition of postsynaptic excitotoxicity, etc. Lastly, we also aim to understand the neuronal and glial pathology in various copper homeostasis disorders. The etiology of glial pathology and its contribution towards neuronal pathology and vice versa underlies the complexity of the neuropathology associated with the copper metabolism disorders.
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Affiliation(s)
- Ashima Bhattacharjee
- Amity Institute of Biotechnology, Amity University, Plot No: 36, 37 & 38, Major Arterial Road, Action Area II, Kadampukur Village, Rajarhat, Newtown, Kolkata, West Bengal 700135, India.
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Xu W, Wu H, Shang L. Identification of novel candidate indicators for assessing zinc status during pregnancy in mice from microarray data. BMC Pharmacol Toxicol 2019; 20:12. [PMID: 30770772 PMCID: PMC6377758 DOI: 10.1186/s40360-019-0288-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2018] [Accepted: 01/29/2019] [Indexed: 11/25/2022] Open
Abstract
Background This study aimed to identify potential zinc status indicators and to clarify the mechanisms underlying zinc deficiency-induced organ damage and mortality in mice. Methods The dataset GSE97112, including placental tissues of mice fed diets containing normal and low concentrations of zinc, was downloaded and preprocessed. Differentially expressed genes (DEGs) were calculated and identified for zinc deficiency-related gene clusters by using the weighed gene co-expression network analysis (WGCNA) algorithm. The Gene Ontology (GO)-Biological Process (BP) and KEGG pathway of genes in the zinc deficiency-related WGCNA modules were analyzed, and the protein-protein interaction (PPI) network was constructed. In addition, modules of the PPI network were identified, and transcription factors (TFs) and miRNAs regulating DEGs were predicted. Finally, drug-gene interactions were selected. Results A total of 1055 DEGs containing 586 up- and 469 down-regulated genes were obtained. Three modules based on WGCNA had high correlation with degree of zinc deficiency. Annexin A1 (ANXA1), C-C motif chemokine receptor 3 (CCR3), C-X-C motif chemokine receptor 2 (CXCR2), and interleukin 2 (IL-2) were hub nodes in the PPI network. Three modules in the PPI network were identified, including module 1 associated with olfactory conduction and module 2 associated with inflammatory response. ANXA1, CCR3, and IL-2 were regulated by TFs. In addition, CXCR2, ANXA, and IL-2 were drug targets. Conclusion CXCR2, ANXA1, and CCR3 as well as olfactory receptor-related genes (proteins) may be used as biomarkers to assess zinc status in mice.
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Affiliation(s)
- Wan Xu
- The Fourth Military Medical University, Xi'an, Shaanxi Province, 710032, China.,Department of Obstetrics and Gynecology, PLA Army General Hospital, No.5 Nanmencang, Dongcheng District, Beijing, 100700, China
| | - Hongyan Wu
- Department of Obstetrics and Gynecology, PLA Army General Hospital, No.5 Nanmencang, Dongcheng District, Beijing, 100700, China
| | - Lixin Shang
- Department of Obstetrics and Gynecology, PLA Army General Hospital, No.5 Nanmencang, Dongcheng District, Beijing, 100700, China.
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13
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Yamada Y, Prosser RA. Copper in the suprachiasmatic circadian clock: A possible link between multiple circadian oscillators. Eur J Neurosci 2018; 51:47-70. [PMID: 30269387 DOI: 10.1111/ejn.14181] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2018] [Revised: 09/05/2018] [Accepted: 09/17/2018] [Indexed: 01/07/2023]
Abstract
The mammalian circadian clock in the suprachiasmatic nucleus (SCN) is very robust, able to coordinate our daily physiological and behavioral rhythms with exquisite accuracy. Simultaneously, the SCN clock is highly sensitive to environmental timing cues such as the solar cycle. This duality of resiliency and sensitivity may be sustained in part by a complex intertwining of three cellular oscillators: transcription/translation, metabolic/redox, and membrane excitability. We suggest here that one of the links connecting these oscillators may be forged from copper (Cu). Cellular Cu levels are highly regulated in the brain and peripherally, and Cu affects cellular metabolism, redox state, cell signaling, and transcription. We have shown that both Cu chelation and application induce nighttime phase shifts of the SCN clock in vitro and that these treatments affect glutamate, N-methyl-D-aspartate receptor, and associated signaling processes differently. More recently we found that Cu induces mitogen-activated protein kinase-dependent phase shifts, while the mechanisms by which Cu removal induces phase shifts remain unclear. Lastly, we have found that two Cu transporters are expressed in the SCN, and that one of these transporters (ATP7A) exhibits a day/night rhythm. Our results suggest that Cu homeostasis is tightly regulated in the SCN, and that changes in Cu levels may serve as a time cue for the circadian clock. We discuss these findings in light of the existing literature and current models of multiple coupled circadian oscillators in the SCN.
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Affiliation(s)
- Yukihiro Yamada
- Department of Biochemistry & Cellular and Molecular Biology, NeuroNET Research Center, University of Tennessee, Knoxville, Tennessee
| | - Rebecca A Prosser
- Department of Biochemistry & Cellular and Molecular Biology, NeuroNET Research Center, University of Tennessee, Knoxville, Tennessee
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14
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Degirmenci S, Olgar Y, Durak A, Tuncay E, Turan B. Cytosolic increased labile Zn 2+ contributes to arrhythmogenic action potentials in left ventricular cardiomyocytes through protein thiol oxidation and cellular ATP depletion. J Trace Elem Med Biol 2018; 48:202-212. [PMID: 29773183 DOI: 10.1016/j.jtemb.2018.04.014] [Citation(s) in RCA: 10] [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: 01/26/2018] [Revised: 04/12/2018] [Accepted: 04/12/2018] [Indexed: 02/06/2023]
Abstract
Intracellular labile (free) Zn2+-level ([Zn2+]i) is low and increases markedly under pathophysiological conditions in cardiomyocytes. High [Zn2+]i is associated with alterations in excitability and ionic-conductances while exact mechanisms are not clarified yet. Therefore, we examined the elevated-[Zn2+]i on some sarcolemmal ionic-mechanisms, which can mediate cardiomyocyte dysfunction. High-[Zn2+]i induced significant changes in action potential (AP) parameters, including depolarization in resting membrane-potential and prolongations in AP-repolarizing phases. We detected also the time-dependent effects such as induction of spontaneous APs at the time of ≥ 3 min following [Zn2+]i increases, a manner of cellular ATP dependent and reversible with disulfide-reducing agent dithiothreitol, DTT. High-[Zn2+]i induced inhibitions in voltage-dependent K+-channel currents, such as transient outward K+-currents, Ito, steady-state currents, Iss and inward-rectifier K+-currents, IK1, reversible with DTT seemed to be responsible from the prolongations in APs. We, for the first time, demonstrated that lowering cellular ATP level induced significant decreaeses in both Iss and IK1, while no effect on Ito. However, the increased-[Zn2+]i could induce marked activation in ATP-sensitive K+-channel currents, IKATP, depending on low cellular ATP and thiol-oxidation levels of these channels. The mRNA levels of Kv4.3, Kv1.4 and Kv2.1 were depressed markedly with increased-[Zn2+]i with no change in mRNA level of Kv4.2, while the mRNA level of IKATP subunit, SUR2A was increased significantly with increased-[Zn2+]i, being reversible with DTT. Overall we demonstrated that high-[Zn2+]i, even if nanomolar levels, alters cardiac function via prolonged APs of cardiomyocytes, at most, due to inhibitions in voltage-dependent K+-currents, although activation of IKATP is playing cardioprotective role, through some biochemical changes in cellular ATP- and thiol-oxidation levels. It seems, a well-controlled [Zn2+]i can be novel therapeutic target for cardiac complications under pathological conditions including oxidative stress.
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Affiliation(s)
- Sinan Degirmenci
- Department of Biophysics, Faculty of Medicine, Ankara University, Ankara, Turkey
| | - Yusuf Olgar
- Department of Biophysics, Faculty of Medicine, Ankara University, Ankara, Turkey
| | - Aysegul Durak
- Department of Biophysics, Faculty of Medicine, Ankara University, Ankara, Turkey
| | - Erkan Tuncay
- Department of Biophysics, Faculty of Medicine, Ankara University, Ankara, Turkey
| | - Belma Turan
- Department of Biophysics, Faculty of Medicine, Ankara University, Ankara, Turkey.
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15
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Grünspan LD, Mussulini BHM, Baggio S, dos Santos PR, Dumas F, Rico EP, de Oliveira DL, Moura S. Teratogenic and anticonvulsant effects of zinc and copper valproate complexes in zebrafish. Epilepsy Res 2018; 139:171-179. [DOI: 10.1016/j.eplepsyres.2018.01.005] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2017] [Revised: 12/05/2017] [Accepted: 01/03/2018] [Indexed: 01/08/2023]
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16
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Wheeler LC, Harms MJ. Human S100A5 binds Ca 2+ and Cu 2+ independently. BMC BIOPHYSICS 2017; 10:8. [PMID: 29201357 PMCID: PMC5700546 DOI: 10.1186/s13628-017-0040-y] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/19/2017] [Accepted: 11/08/2017] [Indexed: 12/21/2022]
Abstract
Background S100A5 is a calcium binding protein found in a small subset of amniote tissues. Little is known about the biological roles of S100A5, but it may be involved in inflammation and olfactory signaling. Previous work indicated that S100A5 displays antagonism between binding of Ca2+ and Cu2+ ions-one of the most commonly cited features of the protein. We set out to characterize the interplay between Ca2+ and Cu2+ binding by S100A5 using isothermal titration calorimetry (ITC), circular dichroism spectroscopy (CD), and analytical ultracentrifugation (AUC). Results We found that human S100A5 is capable of binding both Cu2+ and Ca2+ ions simultaneously. The wildtype protein was extremely aggregation-prone in the presence of Cu2+ and Ca2+. A Cys-free version of S100A5, however, was not prone to precipitation or oligomerization. Mutation of the cysteines does not disrupt the binding of either Ca2+ or Cu2+ to S100A5. In the Cys-free background, we measured Ca2+ and Cu2+ binding in the presence and absence of the other metal using ITC. Saturating concentrations of Ca2+ or Cu2+ do not disrupt the binding of one another. Ca2+ and Cu2+ binding induce structural changes in S100A5, which are measurable using CD spectroscopy. We show via sedimentation velocity AUC that the wildtype protein is prone to the formation of soluble oligomers, which are not present in Cys-free samples. Conclusions S100A5 can bind Ca2+ and Cu2+ ions simultaneously and independently. This observation is in direct contrast to previously-reported antagonism between binding of Cu2+ and Ca2+ ions. The previous result is likely due to metal-dependent aggregation. Little is known about the biology of S100A5, so an accurate understanding of the biochemistry is necessary to make informed biological hypotheses. Our observations suggest the possibility of independent biological functions for Cu2+ and Ca2+ binding by S100A5.
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Affiliation(s)
- Lucas C Wheeler
- Department of Chemistry and Biochemistry, University of Oregon, Eugene, 97403 OR USA.,Insitute of Molecular Biology, University of Oregon, Eugene, 97403 OR USA
| | - Michael J Harms
- Department of Chemistry and Biochemistry, University of Oregon, Eugene, 97403 OR USA.,Insitute of Molecular Biology, University of Oregon, Eugene, 97403 OR USA
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17
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Abstract
Transition metals have been recognized and studied primarily in the context of their essential roles as structural and metabolic cofactors for biomolecules that compose living systems. More recently, an emerging paradigm of transition-metal signaling, where dynamic changes in transitional metal pools can modulate protein function, cell fate, and organism health and disease, has broadened our view of the potential contributions of these essential nutrients in biology. Using copper as a canonical example of transition-metal signaling, we highlight key experiments where direct measurement and/or visualization of dynamic copper pools, in combination with biochemical, physiological, and behavioral studies, have deciphered sources, targets, and physiological effects of copper signals.
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Affiliation(s)
| | - Christopher J Chang
- Departments of Chemistry, Berkeley, California 94720-1460; Molecular and Cell Biology, Berkeley, California 94720-1460; Howard Hughes Medical Institute, University of California Berkeley, Berkeley, California 94720-1460; Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720.
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18
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Blakemore LJ, Trombley PQ. Zinc as a Neuromodulator in the Central Nervous System with a Focus on the Olfactory Bulb. Front Cell Neurosci 2017; 11:297. [PMID: 29033788 PMCID: PMC5627021 DOI: 10.3389/fncel.2017.00297] [Citation(s) in RCA: 56] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2017] [Accepted: 09/06/2017] [Indexed: 12/19/2022] Open
Abstract
The olfactory bulb (OB) is central to the sense of smell, as it is the site of the first synaptic relay involved in the processing of odor information. Odor sensations are first transduced by olfactory sensory neurons (OSNs) before being transmitted, by way of the OB, to higher olfactory centers that mediate olfactory discrimination and perception. Zinc is a common trace element, and it is highly concentrated in the synaptic vesicles of subsets of glutamatergic neurons in some brain regions including the hippocampus and OB. In addition, zinc is contained in the synaptic vesicles of some glycinergic and GABAergic neurons. Thus, zinc released from synaptic vesicles is available to modulate synaptic transmission mediated by excitatory (e.g., N-methyl-D aspartate (NMDA), alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA)) and inhibitory (e.g., gamma-aminobutyric acid (GABA), glycine) amino acid receptors. Furthermore, extracellular zinc can alter the excitability of neurons through effects on a variety of voltage-gated ion channels. Consistent with the notion that zinc acts as a regulator of neuronal activity, we and others have shown zinc modulation (inhibition and/or potentiation) of amino acid receptors and voltage-gated ion channels expressed by OB neurons. This review summarizes the locations and release of vesicular zinc in the central nervous system (CNS), including in the OB. It also summarizes the effects of zinc on various amino acid receptors and ion channels involved in regulating synaptic transmission and neuronal excitability, with a special emphasis on the actions of zinc as a neuromodulator in the OB. An understanding of how neuroactive substances such as zinc modulate receptors and ion channels expressed by OB neurons will increase our understanding of the roles that synaptic circuits in the OB play in odor information processing and transmission.
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Affiliation(s)
- Laura J Blakemore
- Program in Neuroscience, Florida State UniversityTallahassee, FL, United States.,Department of Biological Science, Florida State UniversityTallahassee, FL, United States
| | - Paul Q Trombley
- Program in Neuroscience, Florida State UniversityTallahassee, FL, United States.,Department of Biological Science, Florida State UniversityTallahassee, FL, United States
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19
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Memory and Learning Dysfunction Following Copper Toxicity: Biochemical and Immunohistochemical Basis. Mol Neurobiol 2017; 55:3800-3811. [PMID: 28536976 DOI: 10.1007/s12035-017-0619-y] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2017] [Accepted: 05/12/2017] [Indexed: 12/21/2022]
Abstract
The prototype disease of Cu toxicity in human is Wilson disease, and cognitive impairment is the presenting symptom of it. There is no study correlating Cu-induced excitotoxicity, apoptosis, and astrocytic reaction with memory dysfunction. We report excitotoxicity, apoptosis, and astrocytic reaction of the hippocampus and frontal cortex with memory dysfunction in rat model of Cu toxicity. Thirty-six rats were divided into group I (control) and group II (100 mg/kgBwt/day CuSO4 orally). Y-maze was performed for memory and learning at 0, 30, 60, and 90 days. Frontal and hippocampal free Cu concentration, oxidative stress markers [glutathione (GSH), total antioxidant toxicity (TAC), and malondialdehyde (MDA)], and glutamate were measured by atomic absorption spectroscopy, spectrophotometry, and ELISA, respectively. N-methyl-D-aspartate receptors (NMDARs) NR1, NR2A, and NR2B were done by real-time polymerase chain reaction. Immunohistochemistry for caspase-3 and glial fibrillary acidic protein (GFAP) were done and quantified using the ImageJ software. The glutamate level in hippocampus was increased, and NMDAR expression was decreased at 30, 60, and 90 days in group II compared to group I. In the frontal cortex, glutamate was increased at 90 days, but NMDARs were not significantly different in group II compared to group I. Caspase-3 and GFAP expressions were also higher in group II compared to group I, and these changes were more marked in hippocampus than frontal cortex. These changes correlated with respective free tissue Cu, oxidative stress, and Y-maze attention score. Cu toxicity induces apoptosis and astrocytosis of the hippocampus and frontal cortex through direct or glutamate and oxidative stress pathways, and results in impaired memory and learning.
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20
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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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21
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Tian K, He CC, Xu HN, Wang YX, Wang HG, An D, Heng B, Pang W, Jiang YG, Liu YQ. Zn 2+ reduction induces neuronal death with changes in voltage-gated potassium and sodium channel currents. J Trace Elem Med Biol 2017; 41:66-74. [PMID: 28347465 DOI: 10.1016/j.jtemb.2017.02.011] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/15/2016] [Revised: 12/27/2016] [Accepted: 02/16/2017] [Indexed: 12/12/2022]
Abstract
In the present study, cultured rat primary neurons were exposed to a medium containing N,N,N',N'-tetrakis(2-pyridylmethyl)ethylenediamine (TPEN), a specific cell membrane-permeant Zn2+ chelator, to establish a model of free Zn2+ deficiency in neurons. The effects of TPEN-mediated free Zn2+ ion reduction on neuronal viability and on the performance of voltage-gated sodium channels (VGSCs) and potassium channels (Kvs) were assessed. Free Zn2+ deficiency 1) markedly reduced the neuronal survival rate, 2) reduced the peak amplitude of INa, 3) shifted the INa activation curve towards depolarization, 4) modulated the sensitivity of sodium channel voltage-dependent inactivation to a depolarization voltage, and 5) increased the time course of recovery from sodium channel inactivation. In addition, free Zn2+ deficiency by TPEN notably enhanced the peak amplitude of transient outward K+ currents (IA) and delayed rectifier K+ currents (IK), as well as caused hyperpolarization and depolarization directional shifts in their steady-state activation curves, respectively. Zn2+ supplementation reversed the effects induced by TPEN. Our results indicate that free Zn2+ deficiency causes neuronal damage and alters the dynamic characteristics of VGSC and Kv currents. Thus, neuronal injury caused by free Zn2+ deficiency may correlate with its modulation of the electrophysiological properties of VGSCs and Kvs.
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Affiliation(s)
- Kun Tian
- College of Life Sciences, Nankai University, Tianjin 300071, China
| | - Cong-Cong He
- College of Life Sciences, Nankai University, Tianjin 300071, China
| | - Hui-Nan Xu
- College of Life Sciences, Nankai University, Tianjin 300071, China
| | - Yu-Xiang Wang
- College of Life Sciences, Nankai University, Tianjin 300071, China
| | - Hong-Gang Wang
- College of Life Sciences, Nankai University, Tianjin 300071, China
| | - Di An
- College of Life Sciences, Nankai University, Tianjin 300071, China
| | - Bin Heng
- College of Life Sciences, Nankai University, Tianjin 300071, China
| | - Wei Pang
- Department of Nutrition, Tianjin Institute of Health and Environmental Medicine, Tianjin 300050, China
| | - Yu-Gang Jiang
- Department of Nutrition, Tianjin Institute of Health and Environmental Medicine, Tianjin 300050, China.
| | - Yan-Qiang Liu
- College of Life Sciences, Nankai University, Tianjin 300071, China.
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22
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Hagerty S, Daniels Y, Singletary M, Pustovyy O, Globa L, MacCrehan WA, Muramoto S, Stan G, Lau JW, Morrison EE, Sorokulova I, Vodyanoy V. After oxidation, zinc nanoparticles lose their ability to enhance responses to odorants. Biometals 2016; 29:1005-1018. [PMID: 27649965 DOI: 10.1007/s10534-016-9972-y] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2016] [Accepted: 09/09/2016] [Indexed: 01/13/2023]
Abstract
Electrical responses of olfactory sensory neurons to odorants were examined in the presence of zinc nanoparticles of various sizes and degrees of oxidation. The zinc nanoparticles were prepared by the underwater electrical discharge method and analyzed by atomic force microscopy and X-ray photoelectron spectroscopy. Small (1.2 ± 0.3 nm) zinc nanoparticles significantly enhanced electrical responses of olfactory neurons to odorants. After oxidation, however, these small zinc nanoparticles were no longer capable of enhancing olfactory responses. Larger zinc oxide nanoparticles (15 nm and 70 nm) also did not modulate responses to odorants. Neither zinc nor zinc oxide nanoparticles produced olfactory responses when added without odorants. The enhancement of odorant responses by small zinc nanoparticles was explained by the creation of olfactory receptor dimers initiated by small zinc nanoparticles. The results of this work will clarify the mechanisms for the initial events in olfaction, as well as to provide new ways to alleviate anosmia related to the loss of olfactory receptors.
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Affiliation(s)
- Samantha Hagerty
- Department of Anatomy, Physiology and Pharmacology, Auburn University College of Veterinary Medicine, Auburn, AL, USA
| | - Yasmine Daniels
- Material Measurement Laboratory, National Institute of Standards and Technology, Gaithersburg, MD, USA
| | - Melissa Singletary
- Department of Anatomy, Physiology and Pharmacology, Auburn University College of Veterinary Medicine, Auburn, AL, USA
| | - Oleg Pustovyy
- Department of Anatomy, Physiology and Pharmacology, Auburn University College of Veterinary Medicine, Auburn, AL, USA
| | - Ludmila Globa
- Department of Anatomy, Physiology and Pharmacology, Auburn University College of Veterinary Medicine, Auburn, AL, USA
| | - William A MacCrehan
- Material Measurement Laboratory, National Institute of Standards and Technology, Gaithersburg, MD, USA
| | - Shin Muramoto
- Material Measurement Laboratory, National Institute of Standards and Technology, Gaithersburg, MD, USA
| | - Gheorghe Stan
- Material Measurement Laboratory, National Institute of Standards and Technology, Gaithersburg, MD, USA
| | - June W Lau
- Material Measurement Laboratory, National Institute of Standards and Technology, Gaithersburg, MD, USA
| | - Edward E Morrison
- Department of Anatomy, Physiology and Pharmacology, Auburn University College of Veterinary Medicine, Auburn, AL, USA
| | - Iryna Sorokulova
- Department of Anatomy, Physiology and Pharmacology, Auburn University College of Veterinary Medicine, Auburn, AL, USA
| | - Vitaly Vodyanoy
- Department of Anatomy, Physiology and Pharmacology, Auburn University College of Veterinary Medicine, Auburn, AL, USA.
- Auburn University, 109 Greene Hall, Auburn, AL, 36849, USA.
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23
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Molecular mechanism of Zn2+ inhibition of a voltage-gated proton channel. Proc Natl Acad Sci U S A 2016; 113:E5962-E5971. [PMID: 27647906 DOI: 10.1073/pnas.1604082113] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
Voltage-gated proton (Hv1) channels are involved in many physiological processes, such as pH homeostasis and the innate immune response. Zn2+ is an important physiological inhibitor of Hv1. Sperm cells are quiescent in the male reproductive system due to Zn2+ inhibition of Hv1 channels, but become active once introduced into the low-Zn2+-concentration environment of the female reproductive tract. How Zn2+ inhibits Hv1 is not completely understood. In this study, we use the voltage clamp fluorometry technique to identify the molecular mechanism of Zn2+ inhibition of Hv1. We find that Zn2+ binds to both the activated closed and resting closed states of the Hv1 channel, thereby inhibiting both voltage sensor motion and gate opening. Mutations of some Hv1 residues affect only Zn2+ inhibition of the voltage sensor motion, whereas mutations of other residues also affect Zn2+ inhibition of gate opening. These effects are similar in monomeric and dimeric Hv1 channels, suggesting that the Zn2+-binding sites are localized within each subunit of the dimeric Hv1. We propose that Zn2+ binding has two major effects on Hv1: (i) at low concentrations, Zn2+ binds to one site and prevents the opening conformational change of the pore of Hv1, thereby inhibiting proton conduction; and (ii) at high concentrations, Zn2+, in addition, binds to a second site and inhibits the outward movement of the voltage sensor of Hv1. Elucidating the molecular mechanism of how Zn2+ inhibits Hv1 will further our understanding of Hv1 function and might provide valuable information for future drug development for Hv1 channels.
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24
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Spalloni A, Longone P. Cognitive impairment in amyotrophic lateral sclerosis, clues from the SOD1 mouse. Neurosci Biobehav Rev 2016; 60:12-25. [DOI: 10.1016/j.neubiorev.2015.11.006] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2015] [Revised: 11/09/2015] [Accepted: 11/16/2015] [Indexed: 12/11/2022]
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25
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Jia H, Pustovyy OM, Wang Y, Waggoner P, Beyers RJ, Schumacher J, Wildey C, Morrison E, Salibi N, Denney TS, Vodyanoy VJ, Deshpande G. Enhancement of Odor-Induced Activity in the Canine Brain by Zinc Nanoparticles: A Functional MRI Study in Fully Unrestrained Conscious Dogs. Chem Senses 2015; 41:53-67. [PMID: 26464498 DOI: 10.1093/chemse/bjv054] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Using noninvasive in vivo functional magnetic resonance imaging (fMRI), we demonstrate that the enhancement of odorant response of olfactory receptor neurons by zinc nanoparticles leads to increase in activity in olfaction-related and higher order areas of the dog brain. To study conscious dogs, we employed behavioral training and optical motion tracking for reducing head motion artifacts. We obtained brain activation maps from dogs in both anesthetized state and fully conscious and unrestrained state. The enhancement effect of zinc nanoparticles was higher in conscious dogs with more activation in higher order areas as compared with anesthetized dogs. In conscious dogs, voxels in the olfactory bulb and hippocampus showed higher activity to odorants mixed with zinc nanoparticles as compared with pure odorants, odorants mixed with gold nanoparticles as well as zinc nanoparticles alone. These regions have been implicated in odor intensity processing in other species including humans. If the enhancement effect of zinc nanoparticles observed in vivo are confirmed by future behavioral studies, zinc nanoparticles may provide a way for enhancing the olfactory sensitivity of canines for detection of target substances such as explosives and contraband substances at very low concentrations, which would otherwise go undetected.
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Affiliation(s)
- Hao Jia
- AU MRI Research Center, Department of Electrical & Computer Engineering, Auburn University, Auburn, AL 36832, USA, College of Information Engineering, Taiyuan University of Technology, Taiyuan, Shanxi, China
| | - Oleg M Pustovyy
- Department of Anatomy, Physiology & Pharmacology, Auburn University, Auburn, AL 36832, USA
| | - Yun Wang
- AU MRI Research Center, Department of Electrical & Computer Engineering, Auburn University, Auburn, AL 36832, USA
| | - Paul Waggoner
- Canine Detection Research Institute, Auburn University, Auburn, AL 36832, USA
| | - Ronald J Beyers
- AU MRI Research Center, Department of Electrical & Computer Engineering, Auburn University, Auburn, AL 36832, USA
| | - John Schumacher
- Department of Clinical Sciences, Auburn University, Auburn, AL 36832, USA
| | | | - Edward Morrison
- Department of Anatomy, Physiology & Pharmacology, Auburn University, Auburn, AL 36832, USA
| | - Nouha Salibi
- MR R&D, Siemens Healthcare, Malvern, PA 19355, USA
| | - Thomas S Denney
- AU MRI Research Center, Department of Electrical & Computer Engineering, Auburn University, Auburn, AL 36832, USA, Department of Psychology, Auburn University, Auburn, AL 36832, USA and Alabama Advanced Imaging Consortium, Auburn University and University of Alabama Birmingham, AL, USA
| | - Vitaly J Vodyanoy
- Department of Anatomy, Physiology & Pharmacology, Auburn University, Auburn, AL 36832, USA,
| | - Gopikrishna Deshpande
- AU MRI Research Center, Department of Electrical & Computer Engineering, Auburn University, Auburn, AL 36832, USA, Department of Psychology, Auburn University, Auburn, AL 36832, USA and Alabama Advanced Imaging Consortium, Auburn University and University of Alabama Birmingham, AL, USA
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Jaatinen L, Salemi S, Miettinen S, Hyttinen J, Eberli D. The Combination of Electric Current and Copper Promotes Neuronal Differentiation of Adipose-Derived Stem Cells. Ann Biomed Eng 2014; 43:1014-23. [DOI: 10.1007/s10439-014-1132-3] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2014] [Accepted: 09/19/2014] [Indexed: 01/12/2023]
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27
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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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28
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Marchetti C. Interaction of metal ions with neurotransmitter receptors and potential role in neurodiseases. Biometals 2014; 27:1097-113. [PMID: 25224737 DOI: 10.1007/s10534-014-9791-y] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2014] [Accepted: 09/05/2014] [Indexed: 12/25/2022]
Abstract
There is increasing evidence that toxic metals play a role in diseases of unknown etiology. Their action is often mediated by membrane proteins, and in particular neurotransmitter receptors. This brief review will describe recent findings on the direct interaction of metal ions with ionotropic γ-aminobutyric acid (GABAA) and glutamate receptors, the main inhibitory and excitatory neurotransmitter receptors in the mammalian central nervous system, respectively. Both hyper and hypo function of these receptors are involved in neurological and psychotic syndromes and modulation by metal ions is an important pharmacological issue. The focus will be on three xenobiotic metals, lead (Pb), cadmium (Cd) and nickel (Ni) that have no biological function and whose presence in living organisms is only detrimental, and two trace metals, zinc (Zn) and copper (Cu), which are essential for several enzymatic functions, but can mediate toxic actions if deregulated. Despite limited access to the brain and tight control by metalloproteins, exogenous metals interfere with receptor performances by mimicking physiological ions and occupying one or more modulatory sites on the protein. These interactions will be discussed as a potential cause of neuronal dysfunction.
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Affiliation(s)
- Carla Marchetti
- Istituto di Biofisica, Consiglio Nazionale delle Ricerche, via De Marini, 6, 16149, Genoa, Italy,
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Scheiber IF, Mercer JF, Dringen R. Metabolism and functions of copper in brain. Prog Neurobiol 2014; 116:33-57. [DOI: 10.1016/j.pneurobio.2014.01.002] [Citation(s) in RCA: 213] [Impact Index Per Article: 21.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2013] [Revised: 01/08/2014] [Accepted: 01/08/2014] [Indexed: 12/15/2022]
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30
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Copper and copper proteins in Parkinson's disease. OXIDATIVE MEDICINE AND CELLULAR LONGEVITY 2014; 2014:147251. [PMID: 24672633 PMCID: PMC3941957 DOI: 10.1155/2014/147251] [Citation(s) in RCA: 127] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 10/12/2013] [Accepted: 12/09/2013] [Indexed: 02/07/2023]
Abstract
Copper is a transition metal that has been linked to pathological and beneficial effects in neurodegenerative diseases. In Parkinson's disease, free copper is related to increased oxidative stress, alpha-synuclein oligomerization, and Lewy body formation. Decreased copper along with increased iron has been found in substantia nigra and caudate nucleus of Parkinson's disease patients. Copper influences iron content in the brain through ferroxidase ceruloplasmin activity; therefore decreased protein-bound copper in brain may enhance iron accumulation and the associated oxidative stress. The function of other copper-binding proteins such as Cu/Zn-SOD and metallothioneins is also beneficial to prevent neurodegeneration. Copper may regulate neurotransmission since it is released after neuronal stimulus and the metal is able to modulate the function of NMDA and GABA A receptors. Some of the proteins involved in copper transport are the transporters CTR1, ATP7A, and ATP7B and the chaperone ATOX1. There is limited information about the role of those biomolecules in the pathophysiology of Parkinson's disease; for instance, it is known that CTR1 is decreased in substantia nigra pars compacta in Parkinson's disease and that a mutation in ATP7B could be associated with Parkinson's disease. Regarding copper-related therapies, copper supplementation can represent a plausible alternative, while copper chelation may even aggravate the pathology.
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31
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Multiple effects of copper on NMDA receptor currents. Brain Res 2014; 1542:20-31. [DOI: 10.1016/j.brainres.2013.10.029] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2013] [Revised: 10/15/2013] [Accepted: 10/16/2013] [Indexed: 12/31/2022]
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32
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Ortiz FC, Vergara C, Alcayaga J. Micromolar copper modifies electrical properties and spontaneous discharges of nodose ganglion neurons in vitro. Biometals 2013; 27:45-52. [PMID: 24213945 DOI: 10.1007/s10534-013-9685-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2013] [Accepted: 11/04/2013] [Indexed: 11/25/2022]
Abstract
Copper plays a key role in aerobic cell physiology mainly related to mitochondrial metabolism. This element is also present at higher than basal levels in some central nuclei and indeed, current evidence support copper's role as a neuromodulator in the central nervous system. More recent data indicate that copper may also affect peripheral neuronal activity, but so far, there are not detailed descriptions of what peripheral neuronal characteristics are targeted by copper. Here, we studied the effect of physiological concentration of CuCl2 (μM range) on the activity of peripheral neurons using a preparation of nodose ganglion in vitro. By mean of conventional intracellular recordings passive and active electrical membrane properties were studied. Extracellular copper modified (in a redox-independent manner) the resting membrane potential and the input resistance of the nodose ganglion neurons, increasing the excitability in most of the tested neurons. These results suggest that Cu(2+) modulates the activity of nodose ganglion neurons and support nodose ganglion in vitro preparation as a simple model to study the subcellular mechanisms involved in the Cu(2+) effects on neuron electrical properties.
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Affiliation(s)
- Fernando C Ortiz
- Laboratorio de Fisiología Celular, Facultad de Ciencias, Universidad de Chile, Casilla 653, Santiago, Chile,
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33
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Yamada Y, Prosser RA. Copper chelation and exogenous copper affect circadian clock phase resetting in the suprachiasmatic nucleus in vitro. Neuroscience 2013; 256:252-61. [PMID: 24161278 DOI: 10.1016/j.neuroscience.2013.10.033] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2013] [Revised: 10/14/2013] [Accepted: 10/14/2013] [Indexed: 10/26/2022]
Abstract
Light stimulates specialized retinal ganglion cells to release glutamate (Glu) onto circadian clock neurons of the suprachiasmatic nucleus (SCN). Glu resets the phase of the SCN circadian clock by activating N-methyl-d-aspartate receptors (NMDAR) causing either delays or advances in the clock phase, depending on early- or late-night stimulation, respectively. In addition, these Glu-induced phase shifts require tropomyosin receptor kinase B (TrkB) receptor activity. Previous studies show that copper (Cu) released at hippocampal synapses can inhibit NMDAR activity, and application of exogenous Cu likewise inhibits NMDAR activity. We investigated the effects of Cu in acute SCN brain slices prepared from C57BL/6Nhsd adult, male mice using treatments that decrease or increase available Cu levels in vitro and recorded neuronal activity on the following day. When bath-applied for 10 min at zeitgeber time (ZT) 16 (where ZT0=lights-on in the donor animal colony), the Cu-specific chelators tetrathiomolybdate (TTM) and bathocuproine disulfonate each induce ∼2.5-3-h phase delays in circadian neuronal activity rhythms, similarly to Glu-induced phase delays. Co-application of 10 μM CuCl2, but not 10 μM CoCl₂ blocks TTM-induced phase delays. Furthermore, TTM causes phase advances when applied at ZT23. At both application times, TTM-induced phase shifts are blocked by NMDA or TrkB receptor antagonists. Surprisingly, bath-application of 10 μM Cu alone also induces phase shifts in analogous experiments at ZT16 and ZT23. Inhibiting NMDAR does not block Cu-induced phase shifts. TrkB inhibition blocks Cu-induced phase delays but not phase advances. Thus, increasing and decreasing Cu availability appear to shift the SCN clock phase through different mechanisms, at least at the receptor level. We propose that Cu plays a role in the SCN circadian clock by modulating Glu signaling.
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Affiliation(s)
- Y Yamada
- University of Tennessee, Knoxville, Department of Biochemistry, Cellular and Molecular Biology, Knoxville, TN 37996, USA
| | - R A Prosser
- University of Tennessee, Knoxville, Department of Biochemistry, Cellular and Molecular Biology, Knoxville, TN 37996, USA.
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34
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Blakemore LJ, Tomat E, Lippard SJ, Trombley PQ. Zinc released from olfactory bulb glomeruli by patterned electrical stimulation of the olfactory nerve. Metallomics 2013; 5:208-13. [PMID: 23392381 DOI: 10.1039/c3mt20158a] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Zinc is a trace element with a multitude of roles in biological systems including structural and cofactor functions for proteins. Although most zinc in the central nervous system (CNS) is protein bound, the CNS contains a pool of mobile zinc housed in synaptic vesicles within a subset of neurons. Such mobile zinc occurs in many brain regions, such as the hippocampus, hypothalamus, and cortex, but the olfactory bulb (OB) contains one of the highest such concentrations in the CNS. Zinc is distributed throughout the OB, with the glomerular and granule cell layers containing the highest levels. Here, we visualize vesicular zinc in the OB using zinc-responsive fluorescent probes developed by one of us. Moreover, we provide the first demonstration that vesicular pools of zinc can be released from olfactory nerve terminals within individual glomeruli by patterned electrical stimulation of the olfactory nerve designed to mimic the breathing cycle in rats. We also provide electrophysiological evidence that elevated extracellular zinc potentiates α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptor-mediated synaptic events. AMPA receptors are required for the synchronous activation of neurons within individual OB glomeruli, and zinc-mediated potentiation leads to enhanced synaptic summation.
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Affiliation(s)
- Laura J Blakemore
- Department of Biological Science, The Florida State University, Tallahassee, FL 32306, USA
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35
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McGann JP. Presynaptic inhibition of olfactory sensory neurons: new mechanisms and potential functions. Chem Senses 2013; 38:459-74. [PMID: 23761680 DOI: 10.1093/chemse/bjt018] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
Abstract
Presynaptic inhibition is the suppression of neurotransmitter release from a neuron by inhibitory input onto its presynaptic terminal. In the olfactory system, the primary sensory afferents from the olfactory neuroepithelium to the brain's olfactory bulb are strongly modulated by a presynaptic inhibition that has been studied extensively in brain slices and in vivo. In rodents, this inhibition is mediated by γ-amino butyric acid (GABA) and dopamine released from bulbar interneurons. The specialized GABAergic circuit is now well understood to include a specific subset of GAD65-expressing periglomerular interneurons that stimulate presynaptic GABAB receptors to reduce presynaptic calcium conductance. This inhibition is organized to permit the selective modulation of neurotransmitter release from specific populations of olfactory sensory neurons based on their odorant receptor expression, includes specialized microcircuits to create a tonically active inhibition and a separate feedback inhibition evoked by sensory input, and can be modulated by centrifugal projections from other brain regions. Olfactory nerve output can also be modulated by dopaminergic circuitry, but this literature is more difficult to interpret. Presynaptic inhibition of olfactory afferents may extend their dynamic range but could also create state-dependent or odorant-specific sensory filters on primary sensory representations. New directions exploring this circuit's role in olfactory processing are discussed.
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Affiliation(s)
- John P McGann
- Department of Psychology, Rutgers University, 152 Frelinghuysen Road, Piscataway, NJ 08854, USA.
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36
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Gu Y, Barry J, Gu C. Kv3 channel assembly, trafficking and activity are regulated by zinc through different binding sites. J Physiol 2013; 591:2491-507. [PMID: 23420657 DOI: 10.1113/jphysiol.2013.251983] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
Zinc, a divalent heavy metal ion and an essential mineral for life, regulates synaptic transmission and neuronal excitability via ion channels. However, its binding sites and regulatory mechanisms are poorly understood. Here, we report that Kv3 channel assembly, localization and activity are regulated by zinc through different binding sites. Local perfusion of zinc reversibly reduced spiking frequency of cultured neurons most likely by suppressing Kv3 channels. Indeed, zinc inhibited Kv3.1 channel activity and slowed activation kinetics, independent of its site in the N-terminal T1 domain. Biochemical assays surprisingly identified a novel zinc-binding site in the Kv3.1 C-terminus, critical for channel activity and axonal targeting, but not for the zinc inhibition. Finally, mutagenesis revealed an important role of the junction between the first transmembrane (TM) segment and the first extracellular loop in sensing zinc. Its mutant enabled fast spiking with relative resistance to the zinc inhibition. Therefore, our studies provide novel mechanistic insights into the multifaceted regulation of Kv3 channel activity and localization by divalent heavy metal ions.
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Affiliation(s)
- Yuanzheng Gu
- 182 Rightmire Hall, 1060 Carmack Road, The Ohio State University, Columbus, OH 43210, USA.
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37
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Gaier ED, Eipper BA, Mains RE. Copper signaling in the mammalian nervous system: synaptic effects. J Neurosci Res 2012; 91:2-19. [PMID: 23115049 DOI: 10.1002/jnr.23143] [Citation(s) in RCA: 74] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2012] [Revised: 08/05/2012] [Accepted: 08/17/2012] [Indexed: 12/14/2022]
Abstract
Copper is an essential metal present at high levels in the CNS. Its role as a cofactor in mitochondrial ATP production and in essential cuproenzymes is well defined. Menkes and Wilson's diseases are severe neurodegenerative conditions that demonstrate the importance of Cu transport into the secretory pathway. In the brain, intracellular levels of Cu, which is almost entirely protein bound, exceed extracellular levels by more than 100-fold. Cu stored in the secretory pathway is released in a Ca(2+)-dependent manner and can transiently reach concentrations over 100 μM at synapses. The ability of low micromolar levels of Cu to bind to and modulate the function of γ-aminobutyric acid type A (GABA(A)) receptors, N-methyl-D-aspartate (NMDA) receptors, and voltage-gated Ca(2+) channels contributes to its effects on synaptic transmission. Cu also binds to amyloid precursor protein and prion protein; both proteins are found at synapses and brain Cu homeostasis is disrupted in mice lacking either protein. Especially intriguing is the ability of Cu to affect AMP-activated protein kinase (AMPK), a monitor of cellular energy status. Despite this, few investigators have examined the direct effects of Cu on synaptic transmission and plasticity. Although the variability of results demonstrates complex influences of Cu that are highly method sensitive, these studies nevertheless strongly support important roles for endogenous Cu and new roles for Cu-binding proteins in synaptic function/plasticity and behavior. Further study of the many roles of Cu in nervous system function will reveal targets for intervention in other diseases in which Cu homeostasis is disrupted.
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Affiliation(s)
- E D Gaier
- Department of Neuroscience, University of Connecticut Health Center, Farmington, Connecticut 06030-3401, USA
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38
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Nepravishta R, Polizio F, Paci M, Melino S. A metal-binding site in the RTN1-C protein: new perspectives on the physiological role of a neuronal protein. Metallomics 2012; 4:480-7. [PMID: 22522967 DOI: 10.1039/c2mt20035j] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Reticulon 1-C (RTN1-C) is an ER-associated neuronal protein characterized by horse-shoe-like topology with two transmembrane helices and the N- and C-terminal regions which are supposed in the cytosolic side of ER. The physiological role of this protein is not completely clarified, but several studies have suggested its involvement in the neuronal differentiation, membrane vesicle trafficking and induction of apoptosis. The C-terminal region of RTN1-C is characterized by the presence of a H4 histone consensus sequence that makes it able to interact with nucleic acids and HDAC enzymes both in vitro and in vivo. In the present study a potential metal ion binding motif (HxE/D) at the C-terminal of the RTN1-C has been identified and its capability to bind metals investigated by UV-vis, CD, multidimensional NMR spectroscopy and biological assays. The results suggest a possible implication of the metal ions in the mechanisms of formation of the recently observed RTNs multiprotein complexes contributing to understand the structure and function of this neuronal membrane protein, suggesting a possible effect of the metal binding property on its biological function.
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Affiliation(s)
- Ridvan Nepravishta
- Department of Sciences and Chemical Technologies, University of Rome Tor Vergata, via della Ricerca Scientifica, 00133 Rome, Italy
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39
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Tecchio F, Assenza G, Zappasodi F, Mariani S, Salustri C, Squitti R. Glutamate-mediated primary somatosensory cortex excitability correlated with circulating copper and ceruloplasmin. Int J Alzheimers Dis 2011; 2011:292593. [PMID: 22145081 PMCID: PMC3227495 DOI: 10.4061/2011/292593] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2011] [Revised: 08/08/2011] [Accepted: 08/29/2011] [Indexed: 12/02/2022] Open
Abstract
Objective. To verify whether markers of metal homeostasis are related to a magnetoencephalographic index representative of glutamate-mediated excitability of the primary somatosensory cortex. The index is identified as the source strength of the earliest component (M20) of the somatosensory magnetic fields (SEFs) evoked by right median nerve stimulation at wrist. Method. Thirty healthy right-handed subjects (51 ± 22 years) were enrolled in the study. A source reconstruction algorithm was applied to assess the amount of synchronously activated neurons subtending the M20 and the following SEF component (M30), which is generated by two independent contributions of gabaergic and glutamatergic transmission. Serum copper, ceruloplasmin, iron, transferrin, transferrin saturation, and zinc levels were measured. Results. Total copper and ceruloplasmin negatively correlated with the M20 source strength. Conclusion. This pilot study suggests that higher level of body copper reserve, as marked by ceruloplasmin variations, parallels lower cortical glutamatergic responsiveness.
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Affiliation(s)
- Franca Tecchio
- Laboratory for Electrophysiology for Translational neuroScience (LET'S), Istituto di Scienze e Tecnologie della Cognizione (ISTC), Consiglio Nazionale delle Ricerche (CNR), Fatebenefratelli Hospital Isola Tiberina, Rome, Italy
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40
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Trombley PQ, Blakemore LJ, Hill BJ. Zinc modulation of glycine receptors. Neuroscience 2011; 186:32-8. [PMID: 21530619 PMCID: PMC3118471 DOI: 10.1016/j.neuroscience.2011.04.021] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2010] [Revised: 03/25/2011] [Accepted: 04/11/2011] [Indexed: 10/18/2022]
Abstract
Glycine receptors are widely expressed in the mammalian central nervous system, and previous studies have demonstrated that glycine receptors are modulated by endogenous zinc. Zinc is concentrated in synaptic vesicles in several brain regions but is particularly abundant in the hippocampus and olfactory bulb. In the present study, we used patch-clamp electrophysiology of rat hippocampal and olfactory bulb neurons in primary culture to examine the effects of zinc on glycine receptors. Although glycine has been reported to reach millimolar concentrations during synaptic transmission, most previous studies on the effects of zinc on glycine receptors have used relatively low concentrations of glycine. High concentrations of glycine cause receptor desensitization. Our current results extend our previous demonstration that the modulatory actions of zinc are largely prevented when co-applied with desensitizing concentrations of glycine (300 μM), suggesting that the effects of zinc are dependent on the state of the receptor. In contrast, pre-application of 300 μM zinc, prior to glycine (300 μM) application, causes a slowly developing inhibition with a slow rate of recovery, suggesting that the timing of zinc and glycine release also influences the effects of zinc. Furthermore, previous evidence suggests that synaptically released zinc can gain intracellular access, and we provide the first demonstration that low concentrations of intracellular zinc can potentiate glycine receptors. These results support the notion that zinc has complex effects on glycine receptors and multiple factors may interact to influence the efficacy of glycinergic transmission.
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Affiliation(s)
- P Q Trombley
- Department of Biological Science and Program, Florida State University, Tallahassee, FL 32306, USA.
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41
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Tilton FA, Tilton SC, Bammler TK, Beyer RP, Stapleton PL, Scholz NL, Gallagher EP. Transcriptional impact of organophosphate and metal mixtures on olfaction: copper dominates the chlorpyrifos-induced response in adult zebrafish. AQUATIC TOXICOLOGY (AMSTERDAM, NETHERLANDS) 2011; 102:205-15. [PMID: 21356183 PMCID: PMC3991301 DOI: 10.1016/j.aquatox.2011.01.012] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/07/2010] [Revised: 01/14/2011] [Accepted: 01/27/2011] [Indexed: 05/06/2023]
Abstract
Chemical exposures in fish have been linked to loss of olfaction leading to an inability to detect predators and prey and decreased survival. However, the mechanisms underlying olfactory neurotoxicity are not well characterized, especially in environmental exposures which involve chemical mixtures. We used zebrafish to characterize olfactory transcriptional responses by two model olfactory inhibitors, the pesticide chlorpyrifos (CPF) and mixtures of CPF with the neurotoxic metal copper (Cu). Microarray analysis was performed on RNA from olfactory tissues of zebrafish exposed to CPF alone or to a mixture of CPF and Cu. Gene expression profiles were analyzed using principal component analysis and hierarchical clustering, whereas gene set analysis was used to identify biological themes in the microarray data. Microarray results were confirmed by real-time PCR on genes serving as potential biomarkers of olfactory injury. In addition, we mined our previously published Cu-induced zebrafish olfactory transcriptional response database (Tilton et al., 2008) for the purposes of discriminating pathways of olfaction impacted by either the individual agents or the CPF-Cu mixture transcriptional signatures. CPF exposure altered the expression of gene pathways associated with cellular morphogenesis and odorant binding, but not olfactory signal transduction, a known olfactory pathway for Cu. The mixture profiles shared genes from the Cu and CPF datasets, whereas some genes were altered only by the mixtures. The transcriptional signature of the mixtures was more similar to that in zebrafish exposed to Cu alone than for CPF. In conclusion, exposure to a mixture containing a common environmental metal and pesticide causes a unique transcriptional signature that is heavily influenced by the metal, even when organophosphate predominates.
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Affiliation(s)
- Fred A. Tilton
- Department of Environmental Health and Occupational Health Sciences, University of Washington, Seattle, WA
| | - Susan C. Tilton
- Department of Environmental Health and Occupational Health Sciences, University of Washington, Seattle, WA
| | - Theo K. Bammler
- Department of Environmental Health and Occupational Health Sciences, University of Washington, Seattle, WA
| | - Richard P. Beyer
- Department of Environmental Health and Occupational Health Sciences, University of Washington, Seattle, WA
| | - Patricia L. Stapleton
- Department of Environmental Health and Occupational Health Sciences, University of Washington, Seattle, WA
| | - Nathaniel L. Scholz
- NOAA Fisheries, Northwest Fisheries Science Center, 2725 Montlake Blvd. E., Seattle, WA 98112
| | - Evan P. Gallagher
- Department of Environmental Health and Occupational Health Sciences, University of Washington, Seattle, WA
- Address correspondence to: Evan P. Gallagher, Department of Environmental and Occupational Health Sciences, School of Public Health and Community Medicine, 4225 Roosevelt Way NE Suite 100, University of Washington, Seattle WA 98105-6099. Telephone: (206) 616-4739. Fax: (206) 685-4696.
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42
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Noh J, Chang S, Wang S, Chung J. Dual function of Zn2+ on the intrinsic excitability of dopaminergic neurons in rat substantia nigra. Neuroscience 2011; 175:85-92. [DOI: 10.1016/j.neuroscience.2010.11.019] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2010] [Revised: 11/10/2010] [Accepted: 11/10/2010] [Indexed: 10/18/2022]
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43
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Pushie MJ, Pickering IJ, Martin GR, Tsutsui S, Jirik FR, George GN. Prion protein expression level alters regional copper, iron and zinc content in the mouse brain. Metallomics 2011; 3:206-14. [PMID: 21264406 DOI: 10.1039/c0mt00037j] [Citation(s) in RCA: 75] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The central role of the prion protein (PrP) in a family of fatal neurodegenerate diseases has garnered considerable research interest over the past two decades. Moreover, the role of PrP in neuronal development, as well as its apparent role in metal homeostasis, is increasingly of interest. The host-encoded form of the prion protein (PrP(C)) binds multiple copper atoms via its N-terminal domain and can influence brain copper and iron levels. The importance of PrP(C) to the regulation of brain metal homeostasis and metal distribution, however, is not fully understood. We therefore employed synchrotron-based X-ray fluorescence imaging to map the level and distributions of several key metals in the brains of mice that express different levels of PrP(C). Brain sections from wild-type, prion gene knockout (Prnp(-/-)) and PrP(C) over-expressing mice revealed striking variation in the levels of iron, copper, and even zinc in specific brain regions as a function of PrP(C) expression. Our results indicate that one important function of PrP(C) may be to regulate the amount and distribution of specific metals within the central nervous system. This raises the possibility that PrP(C) levels, or its activity, might regulate the progression of diseases in which altered metal homeostasis is thought to play a pathogenic role such as Alzheimer's, Parkinson's and Wilson's diseases and disorders such as hemochromatosis.
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Affiliation(s)
- M Jake Pushie
- Molecular and Environmental Science Research Group, Department of Geological Sciences, University of Saskatchewan, 114 Science Place, Saskatoon, Saskatchewan, S7N 5E2, Canada.
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44
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Tian Y, Yang Z, Zhang T. Zinc ion as modulator effects on excitability and synaptic transmission in hippocampal CA1 neurons in Wistar rats. Neurosci Res 2010; 68:167-75. [DOI: 10.1016/j.neures.2010.07.2030] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2010] [Revised: 07/02/2010] [Accepted: 07/09/2010] [Indexed: 10/19/2022]
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45
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Wang D, Schreurs BG. Dietary cholesterol modulates the excitability of rabbit hippocampal CA1 pyramidal neurons. Neurosci Lett 2010; 479:327-31. [PMID: 20639007 DOI: 10.1016/j.neulet.2010.05.090] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2010] [Revised: 05/05/2010] [Accepted: 05/30/2010] [Indexed: 11/29/2022]
Abstract
Previous work has shown high dietary cholesterol can affect learning and memory including rabbit eyeblink conditioning and this effect may be due to increased membrane cholesterol and enhanced hippocampal amyloid beta production. This study investigated whether dietary cholesterol modulates rabbit hippocampal CA1 neuron membrane properties known to be involved in rabbit eyeblink conditioning. Whole-cell current clamp recordings in hippocampal neurons from rabbits fed 2 percent cholesterol or normal chow for 8 weeks revealed changes including decreased after-hyperpolarization amplitudes (AHPs) - an index of membrane excitability shown to be important for rabbit eyeblink conditioning. This index was reversed by adding copper to drinking water - a dietary manipulation that can retard rabbit eyeblink conditioning. Evidence of cholesterol effects on membrane excitability was provided by application of methyl-beta-cyclodextrin, a compound that reduces membrane cholesterol, which increased the excitability of hippocampal CA1 neurons.
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Affiliation(s)
- Desheng Wang
- Department of Physiology and Pharmacology, West Virginia University School of Medicine, Morgantown, WV 26506, United States.
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46
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Zinc nanoparticles interact with olfactory receptor neurons. Biometals 2010; 23:1097-103. [PMID: 20559685 DOI: 10.1007/s10534-010-9355-8] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2009] [Accepted: 06/07/2010] [Indexed: 10/19/2022]
Abstract
Zinc metal nanoparticles strongly enhance odorant responses of olfactory receptor neurons. Olfactory receptors belong to the large superfamily of G-protein coupled receptors. A theoretical model based on experimental results explains a stoichiometry of metal nanoparticles receptor interaction. The model is similar to that used by A.V. Hill for the binding reaction between hemoglobin and oxygen. The model predicted that one metal nanoparticle binds two receptor molecules to create a dimer. This result is consistent with the evidence that many G-protein-coupled receptors form dimers or larger oligomers.
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47
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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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Wang LM, Becker JS, Wu Q, Oliveira MF, Bozza FA, Schwager AL, Hoffman JM, Morton KA. Bioimaging of copper alterations in the aging mouse brain by autoradiography, laser ablation inductively coupled plasma mass spectrometry and immunohistochemistry. Metallomics 2010; 2:348-53. [PMID: 21072380 DOI: 10.1039/c003875j] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Copper may play an important role in the brain in aging and neurodegenerative diseases. We compare the active Cu uptake, Cu-containing enzyme levels, and total Cu distribution in the brains of young and aging mice. (67)Cu was administered intravenously to 2, 7-9, and 14 month old mice. Active uptake of (67)Cu in the brain was measured at 24 h by digital phosphor autoradiography. Cerebral superoxide dismutase-1 (SOD-1) and cytochrome-C oxidase subunit-1 (CCO-1) levels were analyzed by immunohistochemistry. The total Cu distribution in brain section was determined by imaging laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS). In aging mice, active (67)Cu uptake and SOD-1 levels were significantly decreased in the brain, whereas blood (67)Cu and CCO-1 levels were similar for all mice, irrespective of age. Paradoxically, global Cu cerebral content was increased in aged mice, suggesting that regulation of active Cu uptake by the brain may be linked to total Cu levels in an attempt to maintain Cu homeostasis. However, focal areas of both decreased Cu uptake and Cu content were noted in the striatum and ventral cortex in aging mice. These focal areas of Cu deficit correspond to the regions of greatest reduction in SOD-1 in the aged mice. In aging, dysregulated Cu homeostasis may result in decreased SOD-1 levels, which may contribute to oxidative vulnerability of the aging brain. This study illustrates the importance of a multi-modality approach in studying the biodistribution and homeostasis of Cu in the brain.
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Affiliation(s)
- Li-Ming Wang
- Department of Radiology, University of Utah, Salt Lake City, UT, USA
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Takeda A, Iwaki H, Ando M, Itagaki K, Suzuki M, Oku N. Zinc differentially acts on components of long-term potentiation at hippocampal CA1 synapses. Brain Res 2010; 1323:59-64. [PMID: 20138845 DOI: 10.1016/j.brainres.2010.01.085] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2009] [Revised: 01/29/2010] [Accepted: 01/29/2010] [Indexed: 10/19/2022]
Abstract
Long-term potentiation (LTP) at hippocampal CA1 synapses consists of N-methyl-d-aspartate (NMDA) receptor-dependent and NMDA receptor-independent forms. The action of divalent heavy metals, which are NMDA receptor antagonists, was examined focusing on the evidence that CA1 LTP induced by a 100-Hz tetanus for 1s is abolished in the presence of 2-amino-5-phosphonovalerate (APV), a NMDA receptor antagonist. Only ZnCl2 (5microM) of heavy metals tested potentiated CA1 LTP. CA1 LTP induced by repeated 100-Hz tetanus (1s, 6 times, 10min interval), which reached a plateau in magnitude, was abolished in the presence of 50microM APV. In this case, CA1 LTP after the first tetanus was potentiated in the presence of 5microM ZnCl2, whereas CA1 LTP after the last tetanus was not potentiated. These results indicate that the magnitude of NMDA receptor-dependent CA1 LTP can be positively shifted with 5microM ZnCl2 in the range of the maximum magnitude. CA1 LTP induced by a 200-Hz tetanus for 1s was not potentiated in the presence of 5microM ZnCl2 and was partially inhibited in the presence of APV. Furthermore, CA1 LTP induced by a 200-Hz tetanus for 1s in the presence of APV was not potentiated in the presence of 5microM ZnCl2, indicating that NMDA receptor-independent CA1 LTP is not potentiated with 5microM ZnCl2. The present study suggests that zinc differentially acts on CA1 LTP components.
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Affiliation(s)
- Atsushi Takeda
- Department of Medical Biochemistry, School of Pharmaceutical Sciences, University of Shizuoka, Global COE, 52-1 Yada, Suruga-ku, Shizuoka 422-8526, Japan.
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Copper in the brain and Alzheimer’s disease. J Biol Inorg Chem 2009; 15:61-76. [DOI: 10.1007/s00775-009-0600-y] [Citation(s) in RCA: 313] [Impact Index Per Article: 20.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2009] [Accepted: 10/13/2009] [Indexed: 12/13/2022]
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