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Aschner M, Martins AC, Oliveira-Paula GH, Skalny AV, Zaitseva IP, Bowman AB, Kirichuk AA, Santamaria A, Tizabi Y, Tinkov AA. Manganese in autism spectrum disorder and attention deficit hyperactivity disorder: The state of the art. Curr Res Toxicol 2024; 6:100170. [PMID: 38737010 PMCID: PMC11088232 DOI: 10.1016/j.crtox.2024.100170] [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: 12/29/2023] [Revised: 03/27/2024] [Accepted: 04/23/2024] [Indexed: 05/14/2024] Open
Abstract
The objective of the present narrative review was to synthesize existing clinical and epidemiological findings linking manganese (Mn) exposure biomarkers to autism spectrum disorder (ASD) and attention deficit hyperactivity disorder (ADHD), and to discuss key pathophysiological mechanisms of neurodevelopmental disorders that may be affected by this metal. Existing epidemiological data demonstrated both direct and inverse association between Mn body burden and ASD, or lack of any relationship. In contrast, the majority of studies revealed significantly higher Mn levels in subjects with ADHD, as well as direct relationship between Mn body burden with hyperactivity and inattention scores in children, although several studies reported contradictory results. Existing laboratory studies demonstrated that impaired attention and hyperactivity in animals following Mn exposure was associated with dopaminergic dysfunction and neuroinflammation. Despite lack of direct evidence on Mn-induced neurobiological alterations in patients with ASD and ADHD, a plethora of studies demonstrated that neurotoxic effects of Mn overexposure may interfere with key mechanisms of pathogenesis inherent to these neurodevelopmental disorders. Specifically, Mn overload was shown to impair not only dopaminergic neurotransmission, but also affect metabolism of glutamine/glutamate, GABA, serotonin, noradrenaline, thus affecting neuronal signaling. In turn, neurotoxic effects of Mn may be associated with its ability to induce oxidative stress, apoptosis, and neuroinflammation, and/or impair neurogenesis. Nonetheless, additional detailed studies are required to evaluate the association between environmental Mn exposure and/or Mn body burden and neurodevelopmental disorders at a wide range of concentrations to estimate the potential dose-dependent effects, as well as environmental and genetic factors affecting this association.
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Affiliation(s)
- Michael Aschner
- Department of Molecular Pharmacology, Albert Einstein College of Medicine, New York, NY 10461, USA
| | - Airton C. Martins
- Department of Molecular Pharmacology, Albert Einstein College of Medicine, New York, NY 10461, USA
| | | | - Anatoly V. Skalny
- Department of Medical Elementology, and Department of Human Ecology and Bioelementology, Peoples' Friendship University of Russia (RUDN University), Moscow 117198, Russia
- Center of Bioelementology and Human Ecology, IM Sechenov First Moscow State Medical University (Sechenov University), Moscow 119435, Russia
| | - Irina P. Zaitseva
- Laboratory of Ecobiomonitoring and Quality Control, Yaroslavl State University, Yaroslavl 150003, Russia
| | - Aaron B. Bowman
- School of Health Sciences, Purdue University, West Lafayette, IN 47907-2051, USA
| | - Anatoly A. Kirichuk
- Department of Medical Elementology, and Department of Human Ecology and Bioelementology, Peoples' Friendship University of Russia (RUDN University), Moscow 117198, Russia
| | - Abel Santamaria
- Facultad de Ciencias, Universidad Nacional Autónoma de México, Mexico City 04510, Mexico
- Laboratorio de Nanotecnología y Nanomedicina, Departamento de Cuidado de la Salud, Universidad Autónoma Metropolitana-Xochimilco, Mexico City 04960, Mexico
| | - Yousef Tizabi
- Department of Pharmacology, Howard University College of Medicine, Washington, DC 20059, USA
| | - Alexey A. Tinkov
- Department of Medical Elementology, and Department of Human Ecology and Bioelementology, Peoples' Friendship University of Russia (RUDN University), Moscow 117198, Russia
- Center of Bioelementology and Human Ecology, IM Sechenov First Moscow State Medical University (Sechenov University), Moscow 119435, Russia
- Laboratory of Ecobiomonitoring and Quality Control, Yaroslavl State University, Yaroslavl 150003, Russia
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2
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Silva-Parra J, Ramírez-Martínez L, Palafox-Gómez C, Sandu C, López-Bayghen E, Vega L, Elizondo G, Loaeza-Loaeza J, Hernández-Sotelo D, Hernández-Kelly LC, Felder-Schmittbuhl MP, Ortega A. Aryl Hydrocarbon Receptor Involvement in the Sodium-Dependent Glutamate/Aspartate Transporter Regulation in Cerebellar Bergmann Glia Cells. ACS Chem Neurosci 2024; 15:1276-1285. [PMID: 38454572 PMCID: PMC10958506 DOI: 10.1021/acschemneuro.4c00046] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2024] [Revised: 02/22/2024] [Accepted: 02/27/2024] [Indexed: 03/09/2024] Open
Abstract
Glutamate, the major excitatory neurotransmitter in the vertebrate brain, exerts its functions through the activation of specific plasma membrane receptors and transporters. Overstimulation of glutamate receptors results in neuronal cell death through a process known as excitotoxicity. A family of sodium-dependent glutamate plasma membrane transporters is responsible for the removal of glutamate from the synaptic cleft, preventing an excitotoxic insult. Glial glutamate transporters carry out more than 90% of the brain glutamate uptake activity and are responsible for glutamate recycling through the GABA/Glutamate/Glutamine shuttle. The aryl hydrocarbon receptor is a ligand-dependent transcription factor that integrates environmental clues through its ability to heterodimerize with different transcription factors. Taking into consideration the fundamental role of glial glutamate transporters in glutamatergic synapses and that these transporters are regulated at the transcriptional, translational, and localization levels in an activity-dependent fashion, in this contribution, we explored the involvement of the aryl hydrocarbon receptor, as a model of environmental integrator, in the regulation of the glial sodium-dependent glutamate/aspartate transporter. Using the model of chick cerebellar Bergmann glia cells, we report herein that the aryl hydrocarbon receptors exert a time-dependent decrease in the transporter mRNA levels and a diminution of its uptake activity. The nuclear factor kappa light chain enhancer of the activated B cell signaling pathway is involved in this regulation. Our results favor the notion of an environmentally dependent regulation of glutamate removal in glial cells and therefore strengthen the notion of the involvement of glial cells in xenobiotic neurotoxic effects.
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Affiliation(s)
- Janisse Silva-Parra
- Departamento
de Toxicología, Centro de Investigación
y de Estudios Avanzados del Instituto Politécnico Nacional, Apartado Postal 14-740, Ciudad de México 07360, Mexico
| | - Leticia Ramírez-Martínez
- Departamento
de Toxicología, Centro de Investigación
y de Estudios Avanzados del Instituto Politécnico Nacional, Apartado Postal 14-740, Ciudad de México 07360, Mexico
| | - Cecilia Palafox-Gómez
- Departamento
de Toxicología, Centro de Investigación
y de Estudios Avanzados del Instituto Politécnico Nacional, Apartado Postal 14-740, Ciudad de México 07360, Mexico
| | - Cristina Sandu
- Centre
National de la Recherche Scientifique, Université
de Strasbourg, Institut des Neurosciences Cellulaires et Intégratives, Strasbourg 00000, France
| | - Esther López-Bayghen
- Departamento
de Toxicología, Centro de Investigación
y de Estudios Avanzados del Instituto Politécnico Nacional, Apartado Postal 14-740, Ciudad de México 07360, Mexico
| | - Libia Vega
- Departamento
de Toxicología, Centro de Investigación
y de Estudios Avanzados del Instituto Politécnico Nacional, Apartado Postal 14-740, Ciudad de México 07360, Mexico
| | - Guillermo Elizondo
- Departamento
de Biología Celular, Centro de Investigación
y de Estudios Avanzados del Instituto Politécnico Nacional, Apartado Postal 14-740, Ciudad de México 07360, Mexico
| | - Jaqueline Loaeza-Loaeza
- Departamento
de Toxicología, Centro de Investigación
y de Estudios Avanzados del Instituto Politécnico Nacional, Apartado Postal 14-740, Ciudad de México 07360, Mexico
| | - Daniel Hernández-Sotelo
- Facultad
de Ciencias Químico-Biológicas, Universidad Autónoma de Guerrero, Chilpancingo 39070, Guerrero, Mexico
| | - Luisa C. Hernández-Kelly
- Departamento
de Toxicología, Centro de Investigación
y de Estudios Avanzados del Instituto Politécnico Nacional, Apartado Postal 14-740, Ciudad de México 07360, Mexico
| | - Marie-Paule Felder-Schmittbuhl
- Centre
National de la Recherche Scientifique, Université
de Strasbourg, Institut des Neurosciences Cellulaires et Intégratives, Strasbourg 00000, France
| | - Arturo Ortega
- Departamento
de Toxicología, Centro de Investigación
y de Estudios Avanzados del Instituto Politécnico Nacional, Apartado Postal 14-740, Ciudad de México 07360, Mexico
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3
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Nassar A, Kodi T, Satarker S, Gurram PC, Fayaz SM, Nampoothiri M. Astrocytic transcription factors REST, YY1, and putative microRNAs in Parkinson's disease and advanced therapeutic strategies. Gene 2024; 892:147898. [PMID: 37832803 DOI: 10.1016/j.gene.2023.147898] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2023] [Revised: 07/10/2023] [Accepted: 10/10/2023] [Indexed: 10/15/2023]
Abstract
Transcription factors (TF) and microRNAs are regulatory factors in astrocytes and are linked to several Parkinson's disease (PD) progression causes, such as disruption of glutamine transporters in astrocytes and concomitant disrupted glutamine uptake and inflammation. REST, a crucial TF, has been documented as an epigenetic repressor that limits the expression of neuronal genes in non-neural cells. REST activity is significantly linked to its corepressors in astrocytes, specifically histone deacetylases (HDACs), CoREST, and MECP2. Another REST-regulating TF, YY1, has been studied in astrocytes, and its interaction with REST has been investigated. In this review, the molecular processes that support the astrocytic control of REST and YY1 in terms of the regulation of glutamate transporter EAAT2 were addressed in a more detailed and comprehensive manner. Both TFs' function in astrocytes and how astrocyte abnormalities cause PD is still a mystery. Moreover, microRNAs (short non-coding RNAs) are key regulators that have been correlated to the expression and regulation of numerous genes linked to PD. The identification of numerous miRs that are engaged in astrocyte dysfunction that triggers PD has been shown. The term "Gut-brain axis" refers to the two systems' mutual communication. Gut microbial dysbiosis, which mediates an imbalance of the gut-brain axis, might contribute to neurodegenerative illnesses through altered astrocytic regulation. New treatment approaches to modify the gut-brain axis and prevent astrocytic repercussions have also been investigated in this review.
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Affiliation(s)
- Ajmal Nassar
- Department of Pharmacology, Manipal College of Pharmaceutical Sciences, Manipal Academy of Higher Education, Manipal 576104, Karnataka, India.
| | - Triveni Kodi
- Department of Pharmacology, Manipal College of Pharmaceutical Sciences, Manipal Academy of Higher Education, Manipal 576104, Karnataka, India.
| | - Sairaj Satarker
- Department of Pharmacology, Manipal College of Pharmaceutical Sciences, Manipal Academy of Higher Education, Manipal 576104, Karnataka, India.
| | - Prasada Chowdari Gurram
- Department of Pharmacology, Manipal College of Pharmaceutical Sciences, Manipal Academy of Higher Education, Manipal 576104, Karnataka, India.
| | - S M Fayaz
- Department of Biotechnology, Manipal Institute of Technology, Manipal Academy of Higher Education, Manipal 576104, Karnataka, India.
| | - Madhavan Nampoothiri
- Department of Pharmacology, Manipal College of Pharmaceutical Sciences, Manipal Academy of Higher Education, Manipal 576104, Karnataka, India.
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Baj J, Flieger W, Barbachowska A, Kowalska B, Flieger M, Forma A, Teresiński G, Portincasa P, Buszewicz G, Radzikowska-Büchner E, Flieger J. Consequences of Disturbing Manganese Homeostasis. Int J Mol Sci 2023; 24:14959. [PMID: 37834407 PMCID: PMC10573482 DOI: 10.3390/ijms241914959] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2023] [Revised: 10/01/2023] [Accepted: 10/04/2023] [Indexed: 10/15/2023] Open
Abstract
Manganese (Mn) is an essential trace element with unique functions in the body; it acts as a cofactor for many enzymes involved in energy metabolism, the endogenous antioxidant enzyme systems, neurotransmitter production, and the regulation of reproductive hormones. However, overexposure to Mn is toxic, particularly to the central nervous system (CNS) due to it causing the progressive destruction of nerve cells. Exposure to manganese is widespread and occurs by inhalation, ingestion, or dermal contact. Associations have been observed between Mn accumulation and neurodegenerative diseases such as manganism, Alzheimer's disease, Parkinson's disease, Huntington's disease, and amyotrophic lateral sclerosis. People with genetic diseases associated with a mutation in the gene associated with impaired Mn excretion, kidney disease, iron deficiency, or a vegetarian diet are at particular risk of excessive exposure to Mn. This review has collected data on the current knowledge of the source of Mn exposure, the experimental data supporting the dispersive accumulation of Mn in the brain, the controversies surrounding the reference values of biomarkers related to Mn status in different matrices, and the competitiveness of Mn with other metals, such as iron (Fe), magnesium (Mg), zinc (Zn), copper (Cu), lead (Pb), calcium (Ca). The disturbed homeostasis of Mn in the body has been connected with susceptibility to neurodegenerative diseases, fertility, and infectious diseases. The current evidence on the involvement of Mn in metabolic diseases, such as type 2 diabetes mellitus/insulin resistance, osteoporosis, obesity, atherosclerosis, and non-alcoholic fatty liver disease, was collected and discussed.
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Affiliation(s)
- Jacek Baj
- Chair and Department of Anatomy, Medical University of Lublin, 20-090 Lublin, Poland; (W.F.); (A.F.)
| | - Wojciech Flieger
- Chair and Department of Anatomy, Medical University of Lublin, 20-090 Lublin, Poland; (W.F.); (A.F.)
| | - Aleksandra Barbachowska
- Department of Plastic, Reconstructive and Burn Surgery, Medical University of Lublin, 21-010 Łęczna, Poland;
| | - Beata Kowalska
- Department of Water Supply and Wastewater Disposal, Lublin University of Technology, 20-618 Lublin, Poland;
| | - Michał Flieger
- Chair and Department of Forensic Medicine, Medical University of Lublin, 20-090 Lublin, Poland; (M.F.); (G.T.); (G.B.)
| | - Alicja Forma
- Chair and Department of Anatomy, Medical University of Lublin, 20-090 Lublin, Poland; (W.F.); (A.F.)
| | - Grzegorz Teresiński
- Chair and Department of Forensic Medicine, Medical University of Lublin, 20-090 Lublin, Poland; (M.F.); (G.T.); (G.B.)
| | - Piero Portincasa
- Clinica Medica A. Murri, Department of Biomedical Sciences & Human Oncology, Medical School, University of Bari, 70124 Bari, Italy;
| | - Grzegorz Buszewicz
- Chair and Department of Forensic Medicine, Medical University of Lublin, 20-090 Lublin, Poland; (M.F.); (G.T.); (G.B.)
| | | | - Jolanta Flieger
- Department of Analytical Chemistry, Medical University of Lublin, 20-093 Lublin, Poland
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5
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Zhou ZX, Xu LJ, Wang HN, Cheng S, Li F, Miao Y, Lei B, Gao F, Wang Z. EphA4/ephrinA3 reverse signaling mediated downregulation of glutamate transporter GLAST in Müller cells in an experimental glaucoma model. Glia 2023; 71:720-741. [PMID: 36416239 DOI: 10.1002/glia.24307] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/01/2022] [Revised: 11/07/2022] [Accepted: 11/12/2022] [Indexed: 11/24/2022]
Abstract
Deficiency of glutamate transporter GLAST in Müller cells may be culpable for excessive extracellular glutamate, which involves in retinal ganglion cell (RGC) damage in glaucoma. We elucidated how GLAST was regulated in rat chronic ocular hypertension (COH) model. Western blot and whole-cell patch-clamp recordings showed that GLAST proteins and GLAST-mediated current densities in Müller cells were downregulated at the early stages of COH. In normal rats, intravitreal injection of the ephrinA3 activator EphA4-Fc mimicked the changes of GLAST in COH retinas. In purified cultured Müller cells, EphA4-Fc treatment reduced GLAST expression at mRNA and protein levels, which was reversed by the tyrosine kinase inhibitor PP2 or transfection with ephrinA3-siRNA (Si-EFNA3), suggesting that EphA4/ephrinA3 reverse signaling mediated GLAST downregulation. EphA4/ephrinA3 reverse signaling-induced GLAST downregulation was mediated by inhibiting PI3K/Akt/NF-κB pathways since EphA4-Fc treatment of cultured Müller cells reduced the levels of p-Akt/Akt and NF-κB p65, which were reversed by transfecting Si-EFNA3. In Müller cells with ephrinA3 knockdown, the PI3K inhibitor LY294002 still decreased the protein levels of NF-κB p65 in the presence of EphA4-Fc, and the mRNA levels of GLAST were reduced by LY294002 and the NF-κB inhibitor SN50, respectively. Pre-injection of the PI3K/Akt pathway activator 740 Y-P reversed the GLAST downregulation in COH retinas. Western blot and TUNEL staining showed that transfecting of Si-EFNA3 reduced Müller cell gliosis and RGC apoptosis in COH retinas. Our results suggest that activated EphA4/ephrinA3 reverse signaling induces GLAST downregulation in Müller cells via inhibiting PI3K/Akt/NF-κB pathways, thus contributing to RGC damage in glaucoma.
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Affiliation(s)
- Zhi-Xin Zhou
- State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science, Institutes of Brain Science, Fudan University, Shanghai, China
| | - Lin-Jie Xu
- State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science, Institutes of Brain Science, Fudan University, Shanghai, China
| | - Hong-Ning Wang
- State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science, Institutes of Brain Science, Fudan University, Shanghai, China
| | - Shuo Cheng
- State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science, Institutes of Brain Science, Fudan University, Shanghai, China
| | - Fang Li
- State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science, Institutes of Brain Science, Fudan University, Shanghai, China
| | - Yanying Miao
- State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science, Institutes of Brain Science, Fudan University, Shanghai, China
| | - Bo Lei
- Institutes of Neuroscience and Third Affiliated Hospital, Henan Provincial People's Hospital, Henan Eye Institute, Henan Eye Hospital, People's Hospital of Zhengzhou University, Zhengzhou University, Zhengzhou, China
| | - Feng Gao
- Eye Institute and Department of Ophthalmology, Eye & ENT Hospital, NHC Key Laboratory of Myopia, Shanghai Key Laboratory of Visual Impairment and Restoration, Fudan University, Shanghai, China
| | - Zhongfeng Wang
- State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science, Institutes of Brain Science, Fudan University, Shanghai, China
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Cellular Pathogenesis of Hepatic Encephalopathy: An Update. Biomolecules 2023; 13:biom13020396. [PMID: 36830765 PMCID: PMC9953810 DOI: 10.3390/biom13020396] [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: 12/01/2022] [Revised: 01/01/2023] [Accepted: 02/17/2023] [Indexed: 02/22/2023] Open
Abstract
Hepatic encephalopathy (HE) is a neuropsychiatric syndrome derived from metabolic disorders due to various liver failures. Clinically, HE is characterized by hyperammonemia, EEG abnormalities, and different degrees of disturbance in sensory, motor, and cognitive functions. The molecular mechanism of HE has not been fully elucidated, although it is generally accepted that HE occurs under the influence of miscellaneous factors, especially the synergistic effect of toxin accumulation and severe metabolism disturbance. This review summarizes the recently discovered cellular mechanisms involved in the pathogenesis of HE. Among the existing hypotheses, ammonia poisoning and the subsequent oxidative/nitrosative stress remain the mainstream theories, and reducing blood ammonia is thus the main strategy for the treatment of HE. Other pathological mechanisms mainly include manganese toxicity, autophagy inhibition, mitochondrial damage, inflammation, and senescence, proposing new avenues for future therapeutic interventions.
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7
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Silva-Parra J, Sandu C, Felder-Schmittbuhl MP, Hernández-Kelly LC, Ortega A. Aryl Hydrocarbon Receptor in Glia Cells: A Plausible Glutamatergic Neurotransmission Orchestrator. Neurotox Res 2023; 41:103-117. [PMID: 36607593 DOI: 10.1007/s12640-022-00623-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2022] [Revised: 11/23/2022] [Accepted: 12/15/2022] [Indexed: 01/07/2023]
Abstract
Glutamate is the major excitatory amino acid in the vertebrate brain. Glutamatergic signaling is involved in most of the central nervous system functions. Its main components, namely receptors, ion channels, and transporters, are tightly regulated at the transcriptional, translational, and post-translational levels through a diverse array of extracellular signals, such as food, light, and neuroactive molecules. An exquisite and well-coordinated glial/neuronal bidirectional communication is required for proper excitatory amino acid signal transactions. Biochemical shuttles such as the glutamate/glutamine and the astrocyte-neuronal lactate represent the fundamental involvement of glial cells in glutamatergic transmission. In fact, the disruption of any of these coordinated biochemical intercellular cascades leads to an excitotoxic insult that underlies some aspects of most of the neurodegenerative diseases characterized thus far. In this contribution, we provide a comprehensive summary of the involvement of the Aryl hydrocarbon receptor, a ligand-dependent transcription factor in the gene expression regulation of glial glutamate transporters. These receptors might serve as potential targets for the development of novel strategies for the treatment of neurodegenerative diseases.
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Affiliation(s)
- Janisse Silva-Parra
- Departamento de Toxicología, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional, Av. IPN 2508, San Pedro Zacatenco, 07360, CDMX, México
| | - Cristina Sandu
- Centre National de la Recherche Scientifique, Institut des Neurosciences Cellulaires et Intégratives, Université de Strasbourg, Strasbourg, France
| | - Marie-Paule Felder-Schmittbuhl
- Centre National de la Recherche Scientifique, Institut des Neurosciences Cellulaires et Intégratives, Université de Strasbourg, Strasbourg, France
| | - Luisa C Hernández-Kelly
- Departamento de Toxicología, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional, Av. IPN 2508, San Pedro Zacatenco, 07360, CDMX, México
| | - Arturo Ortega
- Departamento de Toxicología, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional, Av. IPN 2508, San Pedro Zacatenco, 07360, CDMX, México.
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8
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Pajarillo E, Nyarko-Danquah I, Digman A, Multani HK, Kim S, Gaspard P, Aschner M, Lee E. Mechanisms of manganese-induced neurotoxicity and the pursuit of neurotherapeutic strategies. Front Pharmacol 2022; 13:1011947. [PMID: 36605395 PMCID: PMC9808094 DOI: 10.3389/fphar.2022.1011947] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2022] [Accepted: 12/01/2022] [Indexed: 01/07/2023] Open
Abstract
Chronic exposure to elevated levels of manganese via occupational or environmental settings causes a neurological disorder known as manganism, resembling the symptoms of Parkinson's disease, such as motor deficits and cognitive impairment. Numerous studies have been conducted to characterize manganese's neurotoxicity mechanisms in search of effective therapeutics, including natural and synthetic compounds to treat manganese toxicity. Several potential molecular targets of manganese toxicity at the epigenetic and transcriptional levels have been identified recently, which may contribute to develop more precise and effective gene therapies. This review updates findings on manganese-induced neurotoxicity mechanisms on intracellular insults such as oxidative stress, inflammation, excitotoxicity, and mitophagy, as well as transcriptional dysregulations involving Yin Yang 1, RE1-silencing transcription factor, transcription factor EB, and nuclear factor erythroid 2-related factor 2 that could be targets of manganese neurotoxicity therapies. This review also features intracellular proteins such as PTEN-inducible kinase 1, parkin, sirtuins, leucine-rich repeat kinase 2, and α-synuclein, which are associated with manganese-induced dysregulation of autophagy/mitophagy. In addition, newer therapeutic approaches to treat manganese's neurotoxicity including natural and synthetic compounds modulating excitotoxicity, autophagy, and mitophagy, were reviewed. Taken together, in-depth mechanistic knowledge accompanied by advances in gene and drug delivery strategies will make significant progress in the development of reliable therapeutic interventions against manganese-induced neurotoxicity.
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Affiliation(s)
- Edward Pajarillo
- Department of Pharmaceutical Science, College of Pharmacy and Pharmaceutical Sciences, Florida A&M University, Tallahassee, FL, United States
| | - Ivan Nyarko-Danquah
- Department of Pharmaceutical Science, College of Pharmacy and Pharmaceutical Sciences, Florida A&M University, Tallahassee, FL, United States
| | - Alexis Digman
- Department of Pharmaceutical Science, College of Pharmacy and Pharmaceutical Sciences, Florida A&M University, Tallahassee, FL, United States
| | - Harpreet Kaur Multani
- Department of Biology, College of Science and Technology, Florida A&M University, Tallahassee, FL, United States
| | - Sanghoon Kim
- Department of Pharmaceutical Science, College of Pharmacy and Pharmaceutical Sciences, Florida A&M University, Tallahassee, FL, United States
| | - Patric Gaspard
- Department of Pharmaceutical Science, College of Pharmacy and Pharmaceutical Sciences, Florida A&M University, Tallahassee, FL, United States
| | - Michael Aschner
- Department of Molecular Pharmacology, Albert Einstein College of Medicine, New York, NY, United States
| | - Eunsook Lee
- Department of Pharmaceutical Science, College of Pharmacy and Pharmaceutical Sciences, Florida A&M University, Tallahassee, FL, United States
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9
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Liu P, Tang N, Meng C, Yin Y, Qiu X, Tan L, Sun Y, Song C, Liu W, Liao Y, Lin SH, Ding C. SLC1A3 facilitates Newcastle disease virus replication by regulating glutamine catabolism. Virulence 2022; 13:1407-1422. [PMID: 35993169 PMCID: PMC9415643 DOI: 10.1080/21505594.2022.2112821] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/02/2022] Open
Abstract
As obligate intracellular parasites, viruses rely completely on host metabolic machinery and hijack host nutrients for viral replication. Newcastle disease virus (NDV) causes acute, highly contagious avian disease and functions as an oncolytic agent. NDV efficiently replicates in both chicken and tumour cells. However, how NDV reprograms host cellular metabolism for its efficient replication is still ill-defined. We previously identified a significantly upregulated glutamate transporter gene, solute carrier family 1 member 3 (SLC1A3), during NDV infection via transcriptome analysis. To investigate the potential role of SLC1A3 during NDV infection, we first confirmed the marked upregulation of SLC1A3 in NDV-infected DF-1 or A549 cells through p53 and NF-κB pathways. Knockdown of SLC1A3 inhibited NDV infection. Western blot analysis further confirmed that glutamine, but not glutamate, asparagine, or aspartate, was required for NDV replication. Metabolic flux data showed that NDV promotes the decomposition of glutamine into the tricarboxylic acid cycle. Importantly, the level of glutamate and glutaminolysis were reduced by SLC1A3 knockdown, indicating that SLC1A3 propelled glutaminolysis for glutamate utilization and NDV replication in host cells. Taken together, our data identify that SLC1A3 serves as an important regulator for glutamine metabolism and is hijacked by NDV for its efficient replication during NDV infection. These results improve our understanding of the interaction between NDV and host cellular metabolism and lay the foundation for further investigation of efficient vaccines.
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Affiliation(s)
- Panrao Liu
- Department of Avian Infectious Diseases, Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Science, Shanghai, P.R. China
| | - Ning Tang
- Department of Avian Infectious Diseases, Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Science, Shanghai, P.R. China.,College of Animal Science and Technology, Guangxi University, Nanning, P.R. China
| | - Chunchun Meng
- Department of Avian Infectious Diseases, Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Science, Shanghai, P.R. China
| | - Yuncong Yin
- College of Veterinary Medicine, Yangzhou University, Yangzhou, P.R. China
| | - Xusheng Qiu
- Department of Avian Infectious Diseases, Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Science, Shanghai, P.R. China
| | - Lei Tan
- Department of Avian Infectious Diseases, Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Science, Shanghai, P.R. China
| | - Yingjie Sun
- Department of Avian Infectious Diseases, Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Science, Shanghai, P.R. China
| | - Cuiping Song
- Department of Avian Infectious Diseases, Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Science, Shanghai, P.R. China
| | - Weiwei Liu
- Department of Avian Infectious Diseases, Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Science, Shanghai, P.R. China
| | - Ying Liao
- Department of Avian Infectious Diseases, Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Science, Shanghai, P.R. China
| | - Shu-Hai Lin
- State Key Laboratory of Cellular Stress Biology, Innovation Center for Cell Signaling Network, School of Life Sciences, Xiamen University, Xiamen, P.R. China
| | - Chan Ding
- Department of Avian Infectious Diseases, Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Science, Shanghai, P.R. China.,Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou University, Yangzhou, P.R. China
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10
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Pabian-Jewuła S, Bragiel-Pieczonka A, Rylski M. Ying Yang 1 engagement in brain pathology. J Neurochem 2022; 161:236-253. [PMID: 35199341 DOI: 10.1111/jnc.15594] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2022] [Revised: 02/10/2022] [Accepted: 02/17/2022] [Indexed: 11/27/2022]
Abstract
Herein, we discuss data concerning the involvement of transcription factor Yin Yang 1 (YY1) in the development of brain diseases, highlighting mechanisms of its pathological actions. YY1 plays an important role in the developmental and adult pathology of the nervous system. YY1 is essential for neurulation as well as maintenance and differentiation of neuronal progenitor cells and oligodendrocytes regulating both neural and glial tissues of the brain. Lack of a YY1 gene causes many developmental abnormalities and anatomical malformations of the central nervous system (CNS). Once dysregulated, YY1 exerts multiple neuropathological actions being involved in the induction of many brain disorders like stroke, epilepsy, Alzheimer's and Parkinson's diseases, autism spectrum disorder, dystonia, and brain tumors. Better understanding of YY1's dysfunction in the nervous system may lead to the development of novel therapeutic strategies related to YY1's actions.
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Affiliation(s)
- Sylwia Pabian-Jewuła
- Department of Clinical Cytology, Centre of Postgraduate Medical Education, 99/103 Marymoncka Street, 01-813, Warsaw, Poland
| | - Aneta Bragiel-Pieczonka
- Department of Clinical Cytology, Centre of Postgraduate Medical Education, 99/103 Marymoncka Street, 01-813, Warsaw, Poland
| | - Marcin Rylski
- Department of Radiology, Institute of Psychiatry and Neurology, 9 Sobieski Street, Warsaw, Poland
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11
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Rizor A, Pajarillo E, Son DS, Aschner M, Lee E. Manganese phosphorylates Yin Yang 1 at serine residues to repress EAAT2 in human H4 astrocytes. Toxicol Lett 2022; 355:41-46. [PMID: 34800614 DOI: 10.1016/j.toxlet.2021.11.007] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2021] [Revised: 10/25/2021] [Accepted: 11/16/2021] [Indexed: 10/19/2022]
Abstract
Impairment of the astrocytic glutamate transporter excitatory amino acid transporter 2 (EAAT2) is associated with neurological disorders such as Parkinson's disease (PD), Alzheimer's disease (AD), and manganism, a neurological disorder caused by overexposure to manganese (Mn) which shares the features of sporadic PD. Mechanisms of Mn-induced neurotoxicity include dysregulation of EAAT2 following activation of the transcription factor Yin Yang 1 (YY1) by transcriptional upregulation, but the posttranslational mechanisms by which YY1 is activated to repress EAAT2 remain to be elucidated. In the present study, we tested if Mn activates YY1 through posttranslational phosphorylation in cultured H4 human astrocytes, leading to EAAT2 repression. The results demonstrate that Mn exposure induced phosphorylation of YY1 at serine residues via kinases Aurora B kinase (AurkB) and Casein kinase II (CK2), leading to YY1 nuclear translocation, YY1/HDAC interactions, binding to the EAAT2 promoter, and consequent decreases in EAAT2 promoter activity and mRNA/protein levels. Although further studies are warranted to fully elucidate the mechanisms of Mn-induced YY1 phosphorylation and resultant EAAT2 impairment, our findings indicate that serine phosphorylation of YY1 via AurkB and CK2 is critical, at least in part, to its activation and transcriptional repression of EAAT2.
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Affiliation(s)
- Asha Rizor
- Department of Pharmaceutical Sciences, College of Pharmacy, Florida A&M University, Tallahassee, FL, 32301, USA
| | - Edward Pajarillo
- Department of Pharmaceutical Sciences, College of Pharmacy, Florida A&M University, Tallahassee, FL, 32301, USA
| | - Deok-Soo Son
- Department of Biochemistry and Cancer Biology, Meharry Medical College, Nashville, TN, 37208, USA
| | - Michael Aschner
- Department of Molecular Pharmacology, Albert Einstein College of Medicine Bronx, New York, NY, 10461, USA; Sechenov First Moscow State Medical University, Moscow, Russia
| | - Eunsook Lee
- Department of Pharmaceutical Sciences, College of Pharmacy, Florida A&M University, Tallahassee, FL, 32301, USA.
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12
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Rodríguez-Campuzano AG, Hernández-Kelly LC, Ortega A. DNA Methylation-Dependent Gene Expression Regulation of Glutamate Transporters in Cultured Radial Glial Cells. Mol Neurobiol 2022; 59:1912-1924. [PMID: 35032319 DOI: 10.1007/s12035-022-02746-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2021] [Accepted: 01/11/2022] [Indexed: 11/26/2022]
Abstract
Exposure to xenobiotics has a significant impact in brain physiology that could be liked to an excitotoxic process induced by a massive release of the main excitatory neurotransmitter, L-glutamate. Overstimulation of extra-synaptic glutamate receptors, mainly of the N-methyl-D-aspartate subtype leads to a disturbance of intracellular calcium homeostasis that is critically involved in neuronal death. Hence, glutamate extracellular levels are tightly regulated through its uptake by glial glutamate transporters. It has been observed that glutamate regulates its own removal, both in the short-time frame via a transporter-mediated decrease in the uptake, and in the long-term through the transcriptional control of its gene expression, a process mediated by glutamate receptors that involves the Ca2+/diacylglycerol-dependent protein kinase and the transcription factor Ying Yang 1. Taking into consideration that this transcription factor is a member of the Polycomb complex and thus, part of repressive and activating chromatin remodeling factors, it might direct the interaction of DNA methyltransferases or dioxygenases of methylated cytosines to their target sequences. Here we explored the role of dynamic DNA methylation in the expression and function of glial glutamate transporters. To this end, we used the well-characterized models of primary cultures of chick cerebellar Bergmann glia cells and a human retina-derived Müller glia cell line. A time and dose-dependent increase in global DNA methylation was evident upon glutamate exposure. Under hypomethylation conditions, the glial glutamate transporter protein levels and uptake activity were increased. These results favor the notion that a dynamic DNA methylation program triggered by glutamate in glial cells modulates one of its major functions: glutamate removal.
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Affiliation(s)
- Ada G Rodríguez-Campuzano
- Departamento de Toxicología, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional, Av. IPN 2508, Zacatenco Ciudad de México, 07360, México
| | - Luisa C Hernández-Kelly
- Departamento de Toxicología, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional, Av. IPN 2508, Zacatenco Ciudad de México, 07360, México
| | - Arturo Ortega
- Departamento de Toxicología, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional, Av. IPN 2508, Zacatenco Ciudad de México, 07360, México.
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13
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Hernández-Melchor D, Ramírez-Martínez L, Cid L, Palafox-Gómez C, López-Bayghen E, Ortega A. EAAT1-dependent slc1a3 Transcriptional Control depends on the Substrate Translocation Process. ASN Neuro 2022; 14:17590914221116574. [PMID: 35903937 PMCID: PMC9340397 DOI: 10.1177/17590914221116574] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Glutamate, the major excitatory neurotransmitter in the vertebrate brain, is removed from the synaptic cleft by a family of sodium-dependent transporters expressed in neurons and glial cells. The bulk of glutamate uptake activity occurs in glial cells through the sodium-dependent glutamate/aspartate transporter (EAAT1/GLAST) and glutamate transporter 1 (EAAT2/GLT-1). EAAT1/GLAST is the predominant transporter within the cerebellum. It is highly enriched in Bergmann glial cells that span the cerebellar cortex and wrap the most abundant glutamatergic synapses in the central nervous system, the synapse formed by the parallel fibers and the Purkinje cells. In the past years, it has become evident that Bergmann glial cells are involved in glutamatergic transmission. Glutamate transporters are tightly regulated due to their essential role in tripartite synapses. Glutamate regulates EAAT1/GLAST function and gene expression in a receptor-dependent and receptor-independent manner. Through the use of the non-metabolizable EAAT1/GLAST ligand, D-Aspartate, and the well-established chick cerebellar Bergmann glia primary culture, in this contribution, we demonstrate that EAAT1/GLAST down-regulates its expression and function at the transcriptional level through the activation of a signaling pathway that includes the phosphatidyl inositol 3 kinase (PI3K), the Ca2+/diacylglycerol dependent protein kinase PKC and the nuclear factor κ-light-chain-enhancer of activated B cells (NF-κB). These results favor the notion of an activity-dependent fine-tuning of glutamate recycling and its synaptic transactions through glial cells. Summary statement EAAT1/GLAST down-regulates its expression and function at the transcriptional level by activating a signaling pathway that includes PI3K, PKC and NF-κB, favoring the notion of an activity-dependent fine-tuning of glutamate recycling and its synaptic transactions through glial cells.
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Affiliation(s)
- Dinorah Hernández-Melchor
- Departamento de Toxicología, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional, México City, México
- Science, Technology and Society Program. Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional, México City, México
| | - Leticia Ramírez-Martínez
- Departamento de Toxicología, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional, México City, México
| | - Luis Cid
- Departamento de Toxicología, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional, México City, México
| | - Cecilia Palafox-Gómez
- Departamento de Toxicología, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional, México City, México
| | - Esther López-Bayghen
- Departamento de Toxicología, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional, México City, México
| | - Arturo Ortega
- Departamento de Toxicología, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional, México City, México
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14
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Chen Y, Ma Y, Ji Q, Yang X, Feng X, Yao R, Cheng X, Li T, Wang Y, Wang Z. Intracellular Staphylococcus aureus Infection Decreases Milk Protein Synthesis by Preventing Amino Acid Uptake in Bovine Mammary Epithelial Cells. Front Vet Sci 2021; 8:756375. [PMID: 34869729 PMCID: PMC8636274 DOI: 10.3389/fvets.2021.756375] [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: 08/10/2021] [Accepted: 10/22/2021] [Indexed: 11/13/2022] Open
Abstract
Staphylococcus aureus (S. aureus) is one of the main pathogens in cow mastitis, colonizing mammary tissues and being internalized into mammary epithelial cells, causing intracellular infection in the udder. Milk that is produced by cows that suffer from mastitis due to S. aureus is associated with decreased production and changes in protein composition. However, there is limited information on how mastitis-inducing bacteria affect raw milk, particularly with regard to protein content and protein composition. The main purpose of this work was to examine how S. aureus infection affects milk protein synthesis in bovine mammary epithelial cells (BMECs). BMECs were infected with S. aureus, and milk protein and amino acid levels were determined by ELISA after S. aureus invasion. The activity of mTORC1 signaling and the transcription factors NF-κB and STAT5 and the expression of the amino acid transporters SLC1A3 and SLC7A5 were measured by western blot or immunofluorescence and RT-qPCR. S. aureus was internalized by BMECs in vitro, and the internalized bacteria underwent intracellular proliferation. Eight hours after S. aureus invasion, milk proteins were downregulated, and the level of BMECs that absorbed Glu, Asp, and Leu from the culture medium and the exogenous amino acids induced β-casein synthesis declined. Further, the activity of mTORC1 signaling, NF-κB, and STAT5 was impaired, and SLC1A3 and SLC7A5 were downregulated. Eight hours of treatment with 100 nM rapamycin inhibited NF-κB and STAT5 activity, SLC1A3 and SLC7A5 expression, and milk protein synthesis in BMECs. Thus mTORC1 regulates the expression of SLC1A3 and SLC7A5 through NF-κB and STAT5. These findings constitute a model by which S. aureus infection suppresses milk protein synthesis by decreasing amino acids uptake in BMECs.
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Affiliation(s)
- Yuhao Chen
- State Key Laboratory of Reproductive Regulation & Breeding of Grassland Livestock, School of Life Sciences, Inner Mongolia University, Hohhot, China.,School of Life Sciences and Technology, Jining Normal University, Jining, China
| | - Yuze Ma
- State Key Laboratory of Reproductive Regulation & Breeding of Grassland Livestock, School of Life Sciences, Inner Mongolia University, Hohhot, China
| | - Qiang Ji
- State Key Laboratory of Reproductive Regulation & Breeding of Grassland Livestock, School of Life Sciences, Inner Mongolia University, Hohhot, China
| | - Xiaoru Yang
- State Key Laboratory of Reproductive Regulation & Breeding of Grassland Livestock, School of Life Sciences, Inner Mongolia University, Hohhot, China
| | - Xue Feng
- State Key Laboratory of Reproductive Regulation & Breeding of Grassland Livestock, School of Life Sciences, Inner Mongolia University, Hohhot, China
| | - Ruiyuan Yao
- State Key Laboratory of Reproductive Regulation & Breeding of Grassland Livestock, School of Life Sciences, Inner Mongolia University, Hohhot, China
| | - Xiaoou Cheng
- State Key Laboratory of Reproductive Regulation & Breeding of Grassland Livestock, School of Life Sciences, Inner Mongolia University, Hohhot, China
| | - Tingting Li
- State Key Laboratory of Reproductive Regulation & Breeding of Grassland Livestock, School of Life Sciences, Inner Mongolia University, Hohhot, China
| | - Yanfeng Wang
- State Key Laboratory of Reproductive Regulation & Breeding of Grassland Livestock, School of Life Sciences, Inner Mongolia University, Hohhot, China
| | - Zhigang Wang
- State Key Laboratory of Reproductive Regulation & Breeding of Grassland Livestock, School of Life Sciences, Inner Mongolia University, Hohhot, China
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15
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Pajarillo E, Digman A, Nyarko-Danquah I, Son DS, Soliman KFA, Aschner M, Lee E. Astrocytic transcription factor REST upregulates glutamate transporter EAAT2, protecting dopaminergic neurons from manganese-induced excitotoxicity. J Biol Chem 2021; 297:101372. [PMID: 34756885 PMCID: PMC8626589 DOI: 10.1016/j.jbc.2021.101372] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2021] [Revised: 10/18/2021] [Accepted: 10/27/2021] [Indexed: 11/25/2022] Open
Abstract
Chronic exposure to high levels of manganese (Mn) leads to manganism, a neurological disorder with similar symptoms to those inherent to Parkinson's disease. However, the underlying mechanisms of this pathological condition have yet to be established. Since the human excitatory amino acid transporter 2 (EAAT2) (glutamate transporter 1 in rodents) is predominantly expressed in astrocytes and its dysregulation is involved in Mn-induced excitotoxic neuronal injury, characterization of the mechanisms that mediate the Mn-induced impairment in EAAT2 function is crucial for the development of novel therapeutics against Mn neurotoxicity. Repressor element 1-silencing transcription factor (REST) exerts protective effects in many neurodegenerative diseases. But the effects of REST on EAAT2 expression and ensuing neuroprotection are unknown. Given that the EAAT2 promoter contains REST binding sites, the present study investigated the role of REST in EAAT2 expression at the transcriptional level in astrocytes and Mn-induced neurotoxicity in an astrocyte–neuron coculture system. The results reveal that astrocytic REST positively regulates EAAT2 expression with the recruitment of an epigenetic modifier, cAMP response element-binding protein–binding protein/p300, to its consensus binding sites in the EAAT2 promoter. Moreover, astrocytic overexpression of REST attenuates Mn-induced reduction in EAAT2 expression, leading to attenuation of glutamate-induced neurotoxicity in the astrocyte–neuron coculture system. Our findings demonstrate that astrocytic REST plays a critical role in protection against Mn-induced neurotoxicity by attenuating Mn-induced EAAT2 repression and the ensuing excitotoxic dopaminergic neuronal injury. This indicates that astrocytic REST could be a potential molecular target for the treatment of Mn toxicity and other neurological disorders associated with EAAT2 dysregulation.
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Affiliation(s)
- Edward Pajarillo
- Department of Pharmaceutical Sciences, Florida A&M University, Tallahassee, Florida, USA
| | - Alexis Digman
- Department of Pharmaceutical Sciences, Florida A&M University, Tallahassee, Florida, USA
| | - Ivan Nyarko-Danquah
- Department of Pharmaceutical Sciences, Florida A&M University, Tallahassee, Florida, USA
| | - Deok-Soo Son
- Department of Biochemistry and Cancer Biology, Meharry Medical College, Nashville, Tennessee, USA
| | - Karam F A Soliman
- Department of Pharmaceutical Sciences, Florida A&M University, Tallahassee, Florida, USA
| | - Michael Aschner
- Department of Molecular Pharmacology, Albert Einstein College of Medicine, Bronx, New York, USA; Laboratory of Molecular Nutrition of the Institute for Personalized Medicine, Sechenov First Moscow State Medical University, Moscow, Russia
| | - Eunsook Lee
- Department of Pharmaceutical Sciences, Florida A&M University, Tallahassee, Florida, USA.
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16
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Critical Involvement of Glial Cells in Manganese Neurotoxicity. BIOMED RESEARCH INTERNATIONAL 2021; 2021:1596185. [PMID: 34660781 PMCID: PMC8514895 DOI: 10.1155/2021/1596185] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/22/2021] [Revised: 09/16/2021] [Accepted: 09/21/2021] [Indexed: 12/13/2022]
Abstract
Over the years, most of the research concerning manganese exposure was restricted to the toxicity of neuronal cells. Manganese is an essential trace element that in high doses exerts neurotoxic effects. However, in the last two decades, efforts have shifted toward a more comprehensive approach that takes into account the involvement of glial cells in the development of neurotoxicity as a brain insult. Glial cells provide structural, trophic, and metabolic support to neurons. Nevertheless, these cells play an active role in adult neurogenesis, regulation of synaptogenesis, and synaptic plasticity. Disturbances in glial cell function can lead to neurological disorders, including neurodegenerative diseases. This review highlights the pivotal role that glial cells have in manganese-induced neurotoxicity as well as the most sounding mechanisms involved in the development of this phenomenon.
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17
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Lu R, Cui SS, Wang XX, Chen L, Liu F, Gao J, Wang W. Astrocytic c-Jun N-terminal kinase-histone deacetylase-2 cascade contributes to glutamate transporter-1 decrease and mechanical allodynia following peripheral nerve injury in rats. Brain Res Bull 2021; 175:213-223. [PMID: 34333051 DOI: 10.1016/j.brainresbull.2021.07.024] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2021] [Revised: 07/06/2021] [Accepted: 07/27/2021] [Indexed: 12/21/2022]
Abstract
Decrease of glutamate transporter-1 (GLT-1) in the spinal dorsal horn after nerve injury induces enhanced excitatory transmission and causes persistent pain. Histone deacetylases (HDACs)-catalyzed deacetylation might contribute to the decrease of GLT-1, while the detailed mechanisms have yet to be fully elaborated. Spinal nerve ligation (SNL) induced significant increases of HDAC2 and decreases of GLT-1 in spinal astrocytes. Intrathecal infusion of the HDAC2 inhibitors attenuated the decrease of GLT-1 and enhanced phosphorylation of glutamate receptors. GLT-1 and phosphorylated c-Jun N-terminal kinase (JNK) were highly colocalized in the spinal cord, and a large number of pJNK positive cells were HDAC2 positive. Intrathecally infusion of the JNK inhibitor SP600125 significantly inhibited SNL-induced upregulation of HDAC2. SNL-induced HDAC2 up-regulation could be inhibited by the neutralizing anti-tumor necrosis factor-α (TNF-α) binding protein etanercept or the microglial inhibitor minocycline. In cultured astrocytes, TNF-α induced enhanced phosphorylation of JNK and a significant increase of HDAC2, as well as a remarkable decrease of GLT-1, which could be prevented by SP600125 or the HDAC2 specific inhibitor CAY10683. Our data suggest that astrocytic JNK-HDAC2 cascade contributes to GLT-1 decrease and mechanical allodynia following peripheral nerve injury. Neuroimmune activation after peripheral nerve injury could induce epigenetic modification changes in astrocytes and contribute to chronic pain maintenance.
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Affiliation(s)
- Rui Lu
- National Clinical Research Center for Oral Diseases, State Key Laboratory of Military Stomatology, Shaanxi Key Laboratory of Stomatology, Department of Anesthesiology, School of Stomatology, the Fourth Military Medical University, Shaanxi 710032, China
| | - Shan-Shan Cui
- National Clinical Research Center for Oral Diseases, State Key Laboratory of Military Stomatology, Shaanxi Key Laboratory of Stomatology, Department of Anesthesiology, School of Stomatology, the Fourth Military Medical University, Shaanxi 710032, China; Department of Anesthesiology, Renmin Hospital of Wuhan University, Hubei 430060, China
| | - Xiao-Xia Wang
- National Clinical Research Center for Oral Diseases, State Key Laboratory of Military Stomatology, Shaanxi Key Laboratory of Stomatology, Department of Anesthesiology, School of Stomatology, the Fourth Military Medical University, Shaanxi 710032, China
| | - Lei Chen
- Department of Pain Relief, Tianjin Medical University Cancer Institute and Hospital, National Clinical Research Center for Cancer, Key Laboratory of Cancer Prevention and Therapy (Tianjin), Tianjin's Clinical Research Center for Cancer, Tianjin 300060, China
| | - Fei Liu
- National Clinical Research Center for Oral Diseases, State Key Laboratory of Military Stomatology, Shaanxi Key Laboratory of Stomatology, Department of Anesthesiology, School of Stomatology, the Fourth Military Medical University, Shaanxi 710032, China
| | - Jing Gao
- National Clinical Research Center for Oral Diseases, State Key Laboratory of Military Stomatology, Shaanxi Key Laboratory of Stomatology, Department of Prosthodontics, School of Stomatology, the Fourth Military Medical University, Shaanxi 710032, China.
| | - Wei Wang
- National Clinical Research Center for Oral Diseases, State Key Laboratory of Military Stomatology, Shaanxi Key Laboratory of Stomatology, Department of Anesthesiology, School of Stomatology, the Fourth Military Medical University, Shaanxi 710032, China.
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18
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Rizor A, Pajarillo E, Nyarko-Danquah I, Digman A, Mooneyham L, Son DS, Aschner M, Lee E. Manganese-induced reactive oxygen species activate IκB kinase to upregulate YY1 and impair glutamate transporter EAAT2 function in human astrocytes in vitro. Neurotoxicology 2021; 86:94-103. [PMID: 34310962 DOI: 10.1016/j.neuro.2021.07.004] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2021] [Revised: 07/14/2021] [Accepted: 07/21/2021] [Indexed: 12/19/2022]
Abstract
Dysregulation of the astrocytic glutamate transporter excitatory amino acid transporter 2 (EAAT2) is associated with several neurological disorders, including Parkinson's disease, Alzheimer's disease, and manganism, the latter induced by chronic exposure to high levels of manganese (Mn). Mechanisms of Mn-induced neurotoxicity include impairment of EAAT2 function secondary to the activation of the transcription factor Yin Yang 1 (YY1) by nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB). However, the upstream mechanisms by which Mn-induced NF-κB activates YY1 remain to be elucidated. In the present study, we used the H4 human astrocyte cell line to test if Mn activates YY1 through the canonical NF-κB signaling pathway, leading to EAAT2 repression. The results demonstrate that Mn exposure induced phosphorylation of the upstream kinase IκB kinase (IKK-β), leading to NF-κB p65 translocation, increased YY1 promoter activity, mRNA/protein levels, and consequently repressed EAAT2. Results also demonstrated that Mn-induced oxidative stress and subsequent TNF-α production were upstream of IKK-β activation, as antioxidants attenuated Mn-induced TNF-α production and IKK-β activation. Moreover, TNF-α inhibition attenuated the Mn-induced activation of IKK-β and YY1. Taken together, Mn-induced oxidative stress and TNF-α mediates activation of NF-κB signaling and YY1 upregulation, leading to repression of EAAT2. Thus, targeting reactive oxygen species (ROS), TNF-α and IKK-β may attenuate Mn-induced YY1 activation and consequent EAAT2 repression.
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Affiliation(s)
- Asha Rizor
- Department of Pharmaceutical Sciences, College of Pharmacy, Florida A&M University, Tallahassee, FL, 32301, USA
| | - Edward Pajarillo
- Department of Pharmaceutical Sciences, College of Pharmacy, Florida A&M University, Tallahassee, FL, 32301, USA
| | - Ivan Nyarko-Danquah
- Department of Pharmaceutical Sciences, College of Pharmacy, Florida A&M University, Tallahassee, FL, 32301, USA
| | - Alexis Digman
- Department of Pharmaceutical Sciences, College of Pharmacy, Florida A&M University, Tallahassee, FL, 32301, USA
| | - Leyah Mooneyham
- Department of Pharmaceutical Sciences, College of Pharmacy, Florida A&M University, Tallahassee, FL, 32301, USA
| | - Deok-Soo Son
- Department of Biochemistry and Cancer Biology, Meharry Medical College, Nashville, TN, USA
| | - Michael Aschner
- Department of Molecular Pharmacology, Albert Einstein College of Medicine Bronx, New York, NY, 10461, USA; Sechenov First Moscow State Medical University, Moscow, Russia
| | - Eunsook Lee
- Department of Pharmaceutical Sciences, College of Pharmacy, Florida A&M University, Tallahassee, FL, 32301, USA.
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19
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Rodríguez-Campuzano AG, Ortega A. Glutamate transporters: Critical components of glutamatergic transmission. Neuropharmacology 2021; 192:108602. [PMID: 33991564 DOI: 10.1016/j.neuropharm.2021.108602] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2021] [Revised: 04/09/2021] [Accepted: 04/27/2021] [Indexed: 02/06/2023]
Abstract
Glutamate is the major excitatory neurotransmitter in the vertebrate central nervous system. Once released, it binds to specific membrane receptors and transporters activating a wide variety of signal transduction cascades, as well as its removal from the synaptic cleft in order to avoid its extracellular accumulation and the overstimulation of extra-synaptic receptors that might result in neuronal death through a process known as excitotoxicity. Although neurodegenerative diseases are heterogenous in clinical phenotypes and genetic etiologies, a fundamental mechanism involved in neuronal degeneration is excitotoxicity. Glutamate homeostasis is critical for brain physiology and Glutamate transporters are key players in maintaining low extracellular Glutamate levels. Therefore, the characterization of Glutamate transporters has been an active area of glutamatergic research for the last 40 years. Transporter activity its regulated at different levels: transcriptional and translational control, transporter protein trafficking and membrane mobility, and through extensive post-translational modifications. The elucidation of these mechanisms has emerged as an important piece to shape our current understanding of glutamate actions in the nervous system.
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Affiliation(s)
- Ada G Rodríguez-Campuzano
- Departamento de Toxicología, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional, Apartado Postal 14-740, Ciudad de México, 07000, Mexico
| | - Arturo Ortega
- Departamento de Toxicología, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional, Apartado Postal 14-740, Ciudad de México, 07000, Mexico.
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20
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Tinkov AA, Paoliello MMB, Mazilina AN, Skalny AV, Martins AC, Voskresenskaya ON, Aaseth J, Santamaria A, Notova SV, Tsatsakis A, Lee E, Bowman AB, Aschner M. Molecular Targets of Manganese-Induced Neurotoxicity: A Five-Year Update. Int J Mol Sci 2021; 22:4646. [PMID: 33925013 PMCID: PMC8124173 DOI: 10.3390/ijms22094646] [Citation(s) in RCA: 45] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2021] [Revised: 04/22/2021] [Accepted: 04/25/2021] [Indexed: 12/16/2022] Open
Abstract
Understanding of the immediate mechanisms of Mn-induced neurotoxicity is rapidly evolving. We seek to provide a summary of recent findings in the field, with an emphasis to clarify existing gaps and future research directions. We provide, here, a brief review of pertinent discoveries related to Mn-induced neurotoxicity research from the last five years. Significant progress was achieved in understanding the role of Mn transporters, such as SLC39A14, SLC39A8, and SLC30A10, in the regulation of systemic and brain manganese handling. Genetic analysis identified multiple metabolic pathways that could be considered as Mn neurotoxicity targets, including oxidative stress, endoplasmic reticulum stress, apoptosis, neuroinflammation, cell signaling pathways, and interference with neurotransmitter metabolism, to name a few. Recent findings have also demonstrated the impact of Mn exposure on transcriptional regulation of these pathways. There is a significant role of autophagy as a protective mechanism against cytotoxic Mn neurotoxicity, yet also a role for Mn to induce autophagic flux itself and autophagic dysfunction under conditions of decreased Mn bioavailability. This ambivalent role may be at the crossroad of mitochondrial dysfunction, endoplasmic reticulum stress, and apoptosis. Yet very recent evidence suggests Mn can have toxic impacts below the no observed adverse effect of Mn-induced mitochondrial dysfunction. The impact of Mn exposure on supramolecular complexes SNARE and NLRP3 inflammasome greatly contributes to Mn-induced synaptic dysfunction and neuroinflammation, respectively. The aforementioned effects might be at least partially mediated by the impact of Mn on α-synuclein accumulation. In addition to Mn-induced synaptic dysfunction, impaired neurotransmission is shown to be mediated by the effects of Mn on neurotransmitter systems and their complex interplay. Although multiple novel mechanisms have been highlighted, additional studies are required to identify the critical targets of Mn-induced neurotoxicity.
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Affiliation(s)
- Alexey A. Tinkov
- Laboratory of Ecobiomonitoring and Quality Control, Yaroslavl State University, 150003 Yaroslavl, Russia;
- Laboratory of Molecular Dietetics, Department of Neurological Diseases and Neurosurgery, Department of Analytical and Forensic Toxicology, IM Sechenov First Moscow State Medical University (Sechenov University), 119435 Moscow, Russia; (O.N.V.); (J.A.); (A.T.)
| | - Monica M. B. Paoliello
- Department of Molecular Pharmacology, Albert Einstein College of Medicine, Bronx, NY 10461, USA; (M.M.B.P.); (A.C.M.)
- Graduate Program in Public Health, Center of Health Sciences, State University of Londrina, Londrina, PR 86038-350, Brazil
| | - Aksana N. Mazilina
- Department of Medical Elementology, Peoples’ Friendship University of Russia (RUDN University), 117198 Moscow, Russia;
| | - Anatoly V. Skalny
- World-Class Research Center “Digital Biodesign and Personalized Healthcare”, IM Sechenov First Moscow State Medical University (Sechenov University), 119435 Moscow, Russia;
- Laboratory of Medical Elementology, KG Razumovsky Moscow State University of Technologies and Management, 109004 Moscow, Russia
| | - Airton C. Martins
- Department of Molecular Pharmacology, Albert Einstein College of Medicine, Bronx, NY 10461, USA; (M.M.B.P.); (A.C.M.)
| | - Olga N. Voskresenskaya
- Laboratory of Molecular Dietetics, Department of Neurological Diseases and Neurosurgery, Department of Analytical and Forensic Toxicology, IM Sechenov First Moscow State Medical University (Sechenov University), 119435 Moscow, Russia; (O.N.V.); (J.A.); (A.T.)
| | - Jan Aaseth
- Laboratory of Molecular Dietetics, Department of Neurological Diseases and Neurosurgery, Department of Analytical and Forensic Toxicology, IM Sechenov First Moscow State Medical University (Sechenov University), 119435 Moscow, Russia; (O.N.V.); (J.A.); (A.T.)
- Research Department, Innlandet Hospital Trust, P.O. Box 104, 2381 Brumunddal, Norway
| | - Abel Santamaria
- Laboratorio de Aminoácidos Excitadores, Instituto Nacional de Neurología y Neurocirugía, SSA, Mexico City 14269, Mexico;
| | - Svetlana V. Notova
- Institute of Bioelementology, Orenburg State University, 460018 Orenburg, Russia;
- Federal Research Centre of Biological Systems and Agro-technologies of the Russian Academy of Sciences, 460000 Orenburg, Russia
| | - Aristides Tsatsakis
- Laboratory of Molecular Dietetics, Department of Neurological Diseases and Neurosurgery, Department of Analytical and Forensic Toxicology, IM Sechenov First Moscow State Medical University (Sechenov University), 119435 Moscow, Russia; (O.N.V.); (J.A.); (A.T.)
- Laboratory of Toxicology, Medical School, University of Crete, Voutes, 700 13 Heraklion, Greece
| | - Eunsook Lee
- Department of Pharmaceutical Sciences, Florida A&M University, Tallahassee, FL 32307, USA;
| | - Aaron B. Bowman
- School of Health Sciences, Purdue University, West Lafayette, IN 47906, USA;
| | - Michael Aschner
- Laboratory of Molecular Dietetics, Department of Neurological Diseases and Neurosurgery, Department of Analytical and Forensic Toxicology, IM Sechenov First Moscow State Medical University (Sechenov University), 119435 Moscow, Russia; (O.N.V.); (J.A.); (A.T.)
- Department of Molecular Pharmacology, Albert Einstein College of Medicine, Bronx, NY 10461, USA; (M.M.B.P.); (A.C.M.)
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21
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Pajarillo E, Nyarko-Danquah I, Adinew G, Rizor A, Aschner M, Lee E. Neurotoxicity mechanisms of manganese in the central nervous system. ADVANCES IN NEUROTOXICOLOGY 2021; 5:215-238. [PMID: 34263091 DOI: 10.1016/bs.ant.2020.11.003] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Affiliation(s)
- Edward Pajarillo
- Department of Pharmaceutical Sciences, Florida A&M University, Tallahassee, FL, United States
| | - Ivan Nyarko-Danquah
- Department of Pharmaceutical Sciences, Florida A&M University, Tallahassee, FL, United States
| | - Getinet Adinew
- Department of Pharmaceutical Sciences, Florida A&M University, Tallahassee, FL, United States
| | - Asha Rizor
- Department of Pharmaceutical Sciences, Florida A&M University, Tallahassee, FL, United States
| | - Michael Aschner
- Department of Molecular Pharmacology, Albert Einstein College of Medicine, Bronx, NY, United States
| | - Eunsook Lee
- Department of Pharmaceutical Sciences, Florida A&M University, Tallahassee, FL, United States
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22
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Li B, Xia M, Zorec R, Parpura V, Verkhratsky A. Astrocytes in heavy metal neurotoxicity and neurodegeneration. Brain Res 2021; 1752:147234. [PMID: 33412145 DOI: 10.1016/j.brainres.2020.147234] [Citation(s) in RCA: 64] [Impact Index Per Article: 21.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2020] [Revised: 11/15/2020] [Accepted: 12/07/2020] [Indexed: 12/14/2022]
Abstract
With the industrial development and progressive increase in environmental pollution, the mankind overexposure to heavy metals emerges as a pressing public health issue. Excessive intake of heavy metals, such as arsenic (As), manganese (Mn), mercury (Hg), aluminium (Al), lead (Pb), nickel (Ni), bismuth (Bi), cadmium (Cd), copper (Cu), zinc (Zn), and iron (Fe), is neurotoxic and it promotes neurodegeneration. Astrocytes are primary homeostatic cells in the central nervous system. They protect neurons against all types of insults, in particular by accumulating heavy metals. However, this makes astrocytes the main target for heavy metals neurotoxicity. Intake of heavy metals affects astroglial homeostatic and neuroprotective cascades including glutamate/GABA-glutamine shuttle, antioxidative machinery and energy metabolism. Deficits in these astroglial pathways facilitate or even instigate neurodegeneration. In this review, we provide a concise outlook on heavy metal-induced astrogliopathies and their association with major neurodegenerative disorders. In particular, we focus on astroglial mechanisms of iron-induced neurotoxicity. Iron deposits in the brain are detected in main neurodegenerative diseases, such as Alzheimer's disease, Parkinson's disease and amyotrophic lateral sclerosis. Accumulation of iron in the brain is associated with motor and cognitive impairments and iron-induced histopathological manifestations may be considered as the potential diagnostic biomarker of neurodegenerative diseases. Effective management of heavy metal neurotoxicity can be regarded as a potential strategy to prevent or retard neurodegenerative pathologies.
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Affiliation(s)
- Baoman Li
- Practical Teaching Centre, School of Forensic Medicine, China Medical University, Shenyang, People's Republic of China.
| | - Maosheng Xia
- Department of Orthopaedics, The First Hospital, China Medical University, Shenyang, People's Republic of China
| | - Robert Zorec
- Celica BIOMEDICAL, Tehnološki Park 24, 1000 Ljubljana, Slovenia; Laboratory of Neuroendocrinology-Molecular Cell Physiology, Institute of Pathophysiology, Faculty of Medicine, University of Ljubljana, Zaloška 4, 1000 Ljubljana, Slovenia
| | - Vladimir Parpura
- Department of Neurobiology, The University of Alabama at Birmingham, Birmingham, AL 35294, USA
| | - Alexei Verkhratsky
- Practical Teaching Centre, School of Forensic Medicine, China Medical University, Shenyang, People's Republic of China; Faculty of Biology, Medicine and Health, The University of Manchester, Manchester, UK; Achucarro Center for Neuroscience, IKERBASQUE, Basque Foundation for Science, 48011 Bilbao, Spain.
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23
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Manganese Accumulation in the Brain via Various Transporters and Its Neurotoxicity Mechanisms. Molecules 2020; 25:molecules25245880. [PMID: 33322668 PMCID: PMC7763224 DOI: 10.3390/molecules25245880] [Citation(s) in RCA: 40] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2020] [Revised: 12/07/2020] [Accepted: 12/09/2020] [Indexed: 12/11/2022] Open
Abstract
Manganese (Mn) is an essential trace element, serving as a cofactor for several key enzymes, such as glutamine synthetase, arginase, pyruvate decarboxylase, and mitochondrial superoxide dismutase. However, its chronic overexposure can result in a neurological disorder referred to as manganism, presenting symptoms similar to those inherent to Parkinson’s disease. The pathological symptoms of Mn-induced toxicity are well-known, but the underlying mechanisms of Mn transport to the brain and cellular toxicity leading to Mn’s neurotoxicity are not completely understood. Mn’s levels in the brain are regulated by multiple transporters responsible for its uptake and efflux, and thus, dysregulation of these transporters may result in Mn accumulation in the brain, causing neurotoxicity. Its distribution and subcellular localization in the brain and associated subcellular toxicity mechanisms have also been extensively studied. This review highlights the presently known Mn transporters and their roles in Mn-induced neurotoxicity, as well as subsequent molecular and cellular dysregulation upon its intracellular uptakes, such as oxidative stress, neuroinflammation, disruption of neurotransmission, α-synuclein aggregation, and amyloidogenesis.
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24
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Zhou J, Jangili P, Son S, Ji MS, Won M, Kim JS. Fluorescent Diagnostic Probes in Neurodegenerative Diseases. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2020; 32:e2001945. [PMID: 32902000 DOI: 10.1002/adma.202001945] [Citation(s) in RCA: 73] [Impact Index Per Article: 18.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/20/2020] [Revised: 05/19/2020] [Indexed: 05/22/2023]
Abstract
Neurodegenerative diseases are debilitating disorders that feature progressive and selective loss of function or structure of anatomically or physiologically associated neuronal systems. Both chronic and acute neurodegenerative diseases are associated with high morbidity and mortality along with the death of neurons in different areas of the brain; moreover, there are few or no effective curative therapy options for treating these disorders. There is an urgent need to diagnose neurodegenerative disease as early as possible, and to distinguish between different disorders with overlapping symptoms that will help to decide the best clinical treatment. Recently, in neurodegenerative disease research, fluorescent-probe-mediated biomarker visualization techniques have been gaining increasing attention for the early diagnosis of neurodegenerative diseases. A survey of fluorescent probes for sensing and imaging biomarkers of neurodegenerative diseases is provided. These imaging probes are categorized based on the different potential biomarkers of various neurodegenerative diseases, and their advantages and disadvantages are discussed. Guides to develop new sensing strategies, recognition mechanisms, as well as the ideal features to further improve neurodegenerative disease fluorescence imaging are also explored.
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Affiliation(s)
- Jin Zhou
- College of Pharmacy, Weifang Medical University, Weifang, 261053, China
- Department of Chemistry, Korea University, Seoul, 02841, South Korea
| | - Paramesh Jangili
- Department of Chemistry, Korea University, Seoul, 02841, South Korea
| | - Subin Son
- Department of Chemistry, Korea University, Seoul, 02841, South Korea
| | - Myung Sun Ji
- Department of Chemistry, Korea University, Seoul, 02841, South Korea
| | - Miae Won
- Department of Chemistry, Korea University, Seoul, 02841, South Korea
| | - Jong Seung Kim
- Department of Chemistry, Korea University, Seoul, 02841, South Korea
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25
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Li ZC, Wang F, Li SJ, Zhao L, Li JY, Deng Y, Zhu XJ, Zhang YW, Peng DJ, Jiang YM. Sodium Para-aminosalicylic Acid Reverses Changes of Glutamate Turnover in Manganese-Exposed Rats. Biol Trace Elem Res 2020; 197:544-554. [PMID: 31838737 DOI: 10.1007/s12011-019-02001-0] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/29/2019] [Accepted: 12/03/2019] [Indexed: 01/26/2023]
Abstract
Sodium para-aminosalicylic acid (PAS-Na) has been used to treat patients with manganism, a neurological disease caused by manganese (Mn) toxicity, although the exact molecular mechanisms are yet unclear. The present study aims to investigate the effect of PAS-Na on glutamate (Glu) turnover of Mn-exposed rats. The results showed that Mn concentrations in the hippocampus, thalamus, striatum, and globus pallidus were increased in Mn-exposed rats. Moreover, the results also demonstrated that subacute Mn exposure (15 mg/kg for 4 weeks) interrupted the homeostasis of Glu by increasing Glu levels but decreasing glutamine (Gln) levels in the hippocampus, thalamus, striatum, and globus pallidus in male Sprague-Dawley rats. These effects lasted even after Mn exposure had been ceased for a period of 6 weeks. Meanwhile the main Glu turnover enzymes [Gln synthetase (GS) and phosphate-activated glutaminase (PAG)] and transporters [Glu/aspartate transporter (GLAST) and Glu transporter-1 (GLT-1)] were also affected by Mn treatment. Additionally, PAS-Na treatment recovered the aforementioned changes induced by Mn. Taken together, these results indicate that Glu turnover might be involved in Mn-induced neurotoxicity. PAS-Na treatment could promote Mn excretions and recover the changes in Glu turnover induced by Mn, and a prolonged PAS-Na treatment may be more effective.
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Affiliation(s)
- Zhao-Cong Li
- Department of Toxicology, School of Public Health, Guangxi Medical University, No. 22, Shuang-yong Rd, Nanning, 530021, Guangxi, China
- Guangxi Colleges and Universities Key Laboratory of Prevention and Control of Highly Prevalent Diseases, Guangxi Medical University, Nanning, China
| | - Fang Wang
- Department of Toxicology, School of Public Health, Guangxi Medical University, No. 22, Shuang-yong Rd, Nanning, 530021, Guangxi, China
- Institute of Toxicology, Guangxi Center for Disease Prevention and Control, Nanning, 530028, China
| | - Shao-Jun Li
- Department of Toxicology, School of Public Health, Guangxi Medical University, No. 22, Shuang-yong Rd, Nanning, 530021, Guangxi, China
- Guangxi Colleges and Universities Key Laboratory of Prevention and Control of Highly Prevalent Diseases, Guangxi Medical University, Nanning, China
| | - Lin Zhao
- Department of Toxicology, School of Public Health, Guangxi Medical University, No. 22, Shuang-yong Rd, Nanning, 530021, Guangxi, China
- Guangxi Colleges and Universities Key Laboratory of Prevention and Control of Highly Prevalent Diseases, Guangxi Medical University, Nanning, China
| | - Jun-Yan Li
- Department of Toxicology, School of Public Health, Guangxi Medical University, No. 22, Shuang-yong Rd, Nanning, 530021, Guangxi, China
- Guangxi Colleges and Universities Key Laboratory of Prevention and Control of Highly Prevalent Diseases, Guangxi Medical University, Nanning, China
| | - Yue Deng
- Department of Toxicology, School of Public Health, Guangxi Medical University, No. 22, Shuang-yong Rd, Nanning, 530021, Guangxi, China
- Guangxi Colleges and Universities Key Laboratory of Prevention and Control of Highly Prevalent Diseases, Guangxi Medical University, Nanning, China
| | - Xiao-Juan Zhu
- Department of Toxicology, School of Public Health, Guangxi Medical University, No. 22, Shuang-yong Rd, Nanning, 530021, Guangxi, China
- Guangxi Colleges and Universities Key Laboratory of Prevention and Control of Highly Prevalent Diseases, Guangxi Medical University, Nanning, China
| | - Yu-Wen Zhang
- Department of Toxicology, School of Public Health, Guangxi Medical University, No. 22, Shuang-yong Rd, Nanning, 530021, Guangxi, China
- Guangxi Colleges and Universities Key Laboratory of Prevention and Control of Highly Prevalent Diseases, Guangxi Medical University, Nanning, China
| | - Dong-Jie Peng
- Department of Toxicology, School of Public Health, Guangxi Medical University, No. 22, Shuang-yong Rd, Nanning, 530021, Guangxi, China
- Guangxi Colleges and Universities Key Laboratory of Prevention and Control of Highly Prevalent Diseases, Guangxi Medical University, Nanning, China
| | - Yue-Ming Jiang
- Department of Toxicology, School of Public Health, Guangxi Medical University, No. 22, Shuang-yong Rd, Nanning, 530021, Guangxi, China.
- Guangxi Colleges and Universities Key Laboratory of Prevention and Control of Highly Prevalent Diseases, Guangxi Medical University, Nanning, China.
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26
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Pajarillo E, Johnson J, Rizor A, Nyarko-Danquah I, Adinew G, Bornhorst J, Stiboller M, Schwerdtle T, Son DS, Aschner M, Lee E. Astrocyte-specific deletion of the transcription factor Yin Yang 1 in murine substantia nigra mitigates manganese-induced dopaminergic neurotoxicity. J Biol Chem 2020; 295:15662-15676. [PMID: 32893191 PMCID: PMC7667968 DOI: 10.1074/jbc.ra120.015552] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2020] [Revised: 09/02/2020] [Indexed: 12/11/2022] Open
Abstract
Manganese (Mn)-induced neurotoxicity resembles Parkinson's disease (PD), but the mechanisms underpinning its effects remain unknown. Mn dysregulates astrocytic glutamate transporters, GLT-1 and GLAST, and dopaminergic function, including tyrosine hydroxylase (TH). Our previous in vitro studies have shown that Mn repressed GLAST and GLT-1 via activation of transcription factor Yin Yang 1 (YY1). Here, we investigated if in vivo astrocytic YY1 deletion mitigates Mn-induced dopaminergic neurotoxicity, attenuating Mn-induced reduction in GLAST/GLT-1 expression in murine substantia nigra (SN). AAV5-GFAP-Cre-GFP particles were infused into the SN of 8-week-old YY1 flox/flox mice to generate a region-specific astrocytic YY1 conditional knockout (cKO) mouse model. 3 weeks after adeno-associated viral (AAV) infusion, mice were exposed to 330 μg of Mn (MnCl2 30 mg/kg, intranasal instillation, daily) for 3 weeks. After Mn exposure, motor functions were determined in open-field and rotarod tests, followed by Western blotting, quantitative PCR, and immunohistochemistry to assess YY1, TH, GLAST, and GLT-1 levels. Infusion of AAV5-GFAP-Cre-GFP vectors into the SN resulted in region-specific astrocytic YY1 deletion and attenuation of Mn-induced impairment of motor functions, reduction of TH-expressing cells in SN, and TH mRNA/protein levels in midbrain/striatum. Astrocytic YY1 deletion also attenuated the Mn-induced decrease in GLAST/GLT-1 mRNA/protein levels in midbrain. Moreover, YY1 deletion abrogated its interaction with histone deacetylases in astrocytes. These results indicate that astrocytic YY1 plays a critical role in Mn-induced neurotoxicity in vivo, at least in part, by reducing astrocytic GLAST/GLT-1. Thus, YY1 might be a potential target for treatment of Mn toxicity and other neurological disorders associated with dysregulation of GLAST/GLT-1.
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Affiliation(s)
- Edward Pajarillo
- Department of Pharmaceutical Sciences, Florida A&M University, Tallahassee, Florida, USA
| | - James Johnson
- Department of Pharmaceutical Sciences, Florida A&M University, Tallahassee, Florida, USA
| | - Asha Rizor
- Department of Pharmaceutical Sciences, Florida A&M University, Tallahassee, Florida, USA
| | - Ivan Nyarko-Danquah
- Department of Pharmaceutical Sciences, Florida A&M University, Tallahassee, Florida, USA
| | - Getinet Adinew
- Department of Pharmaceutical Sciences, Florida A&M University, Tallahassee, Florida, USA
| | - Julia Bornhorst
- Food Chemistry, Faculty of Mathematics and Natural Sciences, University of Wuppertal, Wuppertal, Germany
| | - Michael Stiboller
- Department of Food Chemistry, Institute of Nutritional Science, University of Potsdam, Nuthetal, Germany
| | - Tania Schwerdtle
- Department of Food Chemistry, Institute of Nutritional Science, University of Potsdam, Nuthetal, Germany
| | - Deok-Soo Son
- Department of Biochemistry and Cancer Biology, Meharry Medical College, Nashville, Tennessee, USA
| | - Michael Aschner
- Department of Molecular Pharmacology, Albert Einstein College of Medicine Bronx, New York, New York, USA
| | - Eunsook Lee
- Department of Pharmaceutical Sciences, Florida A&M University, Tallahassee, Florida, USA.
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Anderson G. Integrating Pathophysiology in Migraine: Role of the Gut Microbiome and Melatonin. Curr Pharm Des 2020; 25:3550-3562. [PMID: 31538885 DOI: 10.2174/1381612825666190920114611] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2019] [Accepted: 09/12/2019] [Indexed: 02/06/2023]
Abstract
BACKGROUND The pathoetiology and pathophysiology of migraine are widely accepted as unknown. METHODS The current article reviews the wide array of data associated with the biological underpinnings of migraine and provides a framework that integrates previously disparate bodies of data. RESULTS The importance of alterations in stress- and pro-inflammatory cytokine- induced gut dysbiosis, especially butyrate production, are highlighted. This is linked to a decrease in the availability of melatonin, and a relative increase in the N-acetylserotonin/melatonin ratio, which has consequences for the heightened glutamatergic excitatory transmission in migraine. It is proposed that suboptimal mitochondria functioning and metabolic regulation drive alterations in astrocytes and satellite glial cells that underpin the vasoregulatory and nociceptive changes in migraine. CONCLUSION This provides a framework not only for classical migraine associated factors, such as calcitonin-gene related peptide and serotonin, but also for wider factors in the developmental pathoetiology of migraine. A number of future research and treatment implications arise, including the clinical utilization of sodium butyrate and melatonin in the management of migraine.
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Affiliation(s)
- George Anderson
- CRC Scotland & London, Eccleston Square, London, United Kingdom
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28
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Jiménez-Torres C, Hernández-Kelly LC, Najimi M, Ortega A. Bisphenol A exposure disrupts aspartate transport in HepG2 cells. J Biochem Mol Toxicol 2020; 34:e22516. [PMID: 32363662 DOI: 10.1002/jbt.22516] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2019] [Revised: 03/17/2020] [Accepted: 04/22/2020] [Indexed: 01/01/2023]
Abstract
The liver is the organ responsible for bisphenol A (BPA) metabolism, an environmental chemical agent. Exposure to this toxin is associated with liver abnormalities and dysfunction. An important role played by excitatory amino acid transporters (EAATs) of the slc1 gene family has been reported in liver injuries. To gain insight into a plausible effect of BPA exposure in the liver glutamate/aspartate transport, using the human hepatoblastoma cell line HepG2, we report a BPA-dependent dynamic regulation of SLC1A3 and SLC1A2. Through the use of radioactive [3 H]- d-aspartate uptake experiments and immunochemical approaches, we characterized time and dose-dependent regulation of the protein levels and function of these transporters after acute exposure to BPA. An increase in nuclear Yin Yang 1 was found. These results suggest an important involvement of the EAATs in liver physiology and its disruption after acute BPA exposure.
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Affiliation(s)
- Catya Jiménez-Torres
- Departamento de Toxicología, Centro de Investigación y de Estudios Avanzados del IPN, Ciudad de México, México
| | - Luisa C Hernández-Kelly
- Departamento de Toxicología, Centro de Investigación y de Estudios Avanzados del IPN, Ciudad de México, México
| | - Mustapha Najimi
- Hepato-Gastroenterolgy Research Pole, Laboratory of Pediatric Hepatology and Cell Therapy, Institut de Recherche Expérimentale et Clinique (IREC), Université́ Catholique de Louvain, Brussels, Belgium
| | - Arturo Ortega
- Departamento de Toxicología, Centro de Investigación y de Estudios Avanzados del IPN, Ciudad de México, México
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29
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Calcineurin Controls Expression of EAAT1/GLAST in Mouse and Human Cultured Astrocytes through Dynamic Regulation of Protein Synthesis and Degradation. Int J Mol Sci 2020; 21:ijms21062213. [PMID: 32210081 PMCID: PMC7139922 DOI: 10.3390/ijms21062213] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2020] [Revised: 03/19/2020] [Accepted: 03/21/2020] [Indexed: 01/28/2023] Open
Abstract
Alterations in the expression of glutamate/aspartate transporter (GLAST) have been associated with several neuropathological conditions including Alzheimer's disease and epilepsy. However, the mechanisms by which GLAST expression is altered are poorly understood. Here we used a combination of pharmacological and genetic approaches coupled with quantitative PCR and Western blot to investigate the mechanism of the regulation of GLAST expression by a Ca2+/calmodulin-activated phosphatase calcineurin (CaN). We show that treatment of cultured hippocampal mouse and fetal human astrocytes with a CaN inhibitor FK506 resulted in a dynamic modulation of GLAST protein expression, being downregulated after 24-48 h, but upregulated after 7 days of continuous FK506 (200 nM) treatment. Protein synthesis, as assessed by puromycin incorporation in neo-synthesized polypeptides, was inhibited already after 1 h of FK506 treatment, while the use of a proteasome inhibitor MG132 (1 μM) shows that GLAST protein degradation was only suppressed after 7 days of FK506 treatment. In astrocytes with constitutive genetic ablation of CaN both protein synthesis and degradation were significantly inhibited. Taken together, our data suggest that, in cultured astrocytes, CaN controls GLAST expression at a posttranscriptional level through regulation of GLAST protein synthesis and degradation.
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30
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Adenosine Receptor A1-A2a Heteromers Regulate EAAT2 Expression and Glutamate Uptake via YY1-Induced Repression of PPAR γ Transcription. PPAR Res 2020; 2020:2410264. [PMID: 32206061 PMCID: PMC7079221 DOI: 10.1155/2020/2410264] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2019] [Accepted: 01/23/2020] [Indexed: 12/29/2022] Open
Abstract
Adenosine receptors A1 (A1AR) and A2a (A2aAR) play an important role in regulating glutamate uptake to avoid glutamate accumulation that causes excitotoxicity in the brain; however, the precise mechanism of the effects of A1AR and A2aAR is unclear. Herein, we report that expression of the A1AR protein in the astrocyte membrane and the level of intracellular glutamate were decreased, while expression of the A2aR protein was elevated in cells exposed to oxygen-glucose deprivation (OGD) conditions. Coimmunoprecipitation (Co-IP) experiments showed that A1AR interacts with A2aAR under OGD conditions. The activation of A1AR and inactivation of A2aAR by 2-chloro-N6-cyclopentyladenosine (CCPA) and SCH58251, respectively, partly reversed OGD-mediated glutamate uptake dysfunction, elevated EAAT2, and PPARγ protein levels, and suppressed the expression of Ying Yang 1 (YY1). Both the silencing of YY1 and the activation of PPARγ upregulated EAAT2 expression. Moreover, YY1 silencing elevated the PPARγ level under both normal and OGD conditions. Histone deacetylase (HDAC)1 was found to interact with YY1, and HDAC1 silencing improved PPARγ promoter activity. Taken together, our findings suggest that A1AR-A2aAR heteromers regulate EAAT2 expression and glutamate uptake through the YY1-mediated recruitment of HDAC1 to the PPARγ promoter region.
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Hindeya Gebreyesus H, Gebrehiwot Gebremichael T. The Potential Role of Astrocytes in Parkinson's Disease (PD). Med Sci (Basel) 2020; 8:E7. [PMID: 32012713 PMCID: PMC7151567 DOI: 10.3390/medsci8010007] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2019] [Revised: 08/08/2019] [Accepted: 08/09/2019] [Indexed: 12/11/2022] Open
Abstract
Astrocytes are multi-functional cells, now recognized as critical participants in many brain functions. They play a critical physiological role in the clearance of neurotransmitters, such as glutamate and gamma-aminobutyric acid (GABA), and in the regulation of K+ from the space of synaptic clefts. Astrocytes also express the excitatory amino acid transporters (EAATs) and aquaporin-4 (AQP4) water channel, which are involved in both physiological functions and neurodegenerative diseases (ND). Some of the ND are the Alzheimer's (AD), Huntington's (HD), Parkinson's diseases (PD), Cerebral edema, amyotrophic lateral sclerosis (ALS), and epilepsy pathological conditions in specific regions of the CNS. Parkinson's disease is the second most common age-related neurodegenerative disorder, characterized by degeneration of dopaminergic neurons of the substantia nigra pars compacta (SNpc). These project to the striatum, forming an important pathway within the basal ganglia. Mostly, PD has no clear etiology, and the mechanism of dopaminergic (DA) neuron loss is not well illustrated. The results of various studies suggest that astrocytes are involved in the pathophysiology of PD. Evidence has shown that the down-regulation of EAAT-2/GLT-1 and AQP4 expression is associated with PD pathogenesis. However, controversial results were reported in different experimental studies about the expression and function of EAAT-2/GLT-1 and AQP4, as well as their colocalization in different brain regions, and their involvement in PD development. Therefore, under neurological disorders, Parkinson's disease is related to the genetic and phenotypic change of astrocytes' biology. In this review, the authors summarized recent their research findings, which revealed the involvement of EAAT-2/GLT-1 and AQP4 expression, the physical interaction between EAAT-2/GLT-1 and AQP4 in astrocyte function, and their potential role in the development of PD in SNpc and Subthalamic nucleus (STN) of the basal ganglia nuclei.
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Affiliation(s)
- Hiluf Hindeya Gebreyesus
- School of Medicine, Biomedical Sciences, College of Health Sciences, Mekelle University, P.O. Box: 1871 Mekelle, Tigray, Ethiopia
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Pajarillo E, Rizor A, Lee J, Aschner M, Lee E. The role of astrocytic glutamate transporters GLT-1 and GLAST in neurological disorders: Potential targets for neurotherapeutics. Neuropharmacology 2019; 161:107559. [PMID: 30851309 PMCID: PMC6731169 DOI: 10.1016/j.neuropharm.2019.03.002] [Citation(s) in RCA: 206] [Impact Index Per Article: 41.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2018] [Revised: 02/28/2019] [Accepted: 03/02/2019] [Indexed: 12/12/2022]
Abstract
Glutamate is the primary excitatory neurotransmitter in the central nervous system (CNS) which initiates rapid signal transmission in the synapse before its re-uptake into the surrounding glia, specifically astrocytes. The astrocytic glutamate transporters glutamate-aspartate transporter (GLAST) and glutamate transporter-1 (GLT-1) and their human homologs excitatory amino acid transporter 1 (EAAT1) and 2 (EAAT2), respectively, are the major transporters which take up synaptic glutamate to maintain optimal extracellular glutamic levels, thus preventing accumulation in the synaptic cleft and ensuing excitotoxicity. Growing evidence has shown that excitotoxicity is associated with various neurological disorders, including amyotrophic lateral sclerosis (ALS), Alzheimer's disease (AD), Parkinson's disease (PD), manganism, ischemia, schizophrenia, epilepsy, and autism. While the mechanisms of neurological disorders are not well understood, the dysregulation of GLAST/GLT-1 may play a significant role in excitotoxicity and associated neuropathogenesis. The expression and function of GLAST/GLT-1 may be dysregulated at the genetic, epigenetic, transcriptional or translational levels, leading to high levels of extracellular glutamate and excitotoxicity. Consequently, understanding the regulatory mechanisms of GLAST/GLT-1 has been an area of interest in developing therapeutics for the treatment of neurological disorders. Pharmacological agents including β-lactam antibiotics, estrogen/selective estrogen receptor modulators (SERMs), growth factors, histone deacetylase inhibitors (HDACi), and translational activators have shown significant efficacy in enhancing the expression and function of GLAST/GLT-1 and glutamate uptake both in vitro and in vivo. This comprehensive review will discuss the regulatory mechanisms of GLAST/GLT-1, their association with neurological disorders, and the pharmacological agents which mediate their expression and function. This article is part of the issue entitled 'Special Issue on Neurotransmitter Transporters'.
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Affiliation(s)
- Edward Pajarillo
- Department of Pharmaceutical Sciences, College of Pharmacy, Florida A&M University, Tallahassee, FL, 32301, USA
| | - Asha Rizor
- Department of Pharmaceutical Sciences, College of Pharmacy, Florida A&M University, Tallahassee, FL, 32301, USA
| | - Jayden Lee
- Department of Speech, Language & Hearing Sciences, Boston University, Boston, MA, 02215, USA
| | - Michael Aschner
- Department of Molecular Pharmacology, Albert Einstein College of Medicine, Bronx, NY, 10461, USA
| | - Eunsook Lee
- Department of Pharmaceutical Sciences, College of Pharmacy, Florida A&M University, Tallahassee, FL, 32301, USA.
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Malik AR, Willnow TE. Excitatory Amino Acid Transporters in Physiology and Disorders of the Central Nervous System. Int J Mol Sci 2019; 20:ijms20225671. [PMID: 31726793 PMCID: PMC6888459 DOI: 10.3390/ijms20225671] [Citation(s) in RCA: 88] [Impact Index Per Article: 17.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2019] [Revised: 11/07/2019] [Accepted: 11/11/2019] [Indexed: 12/12/2022] Open
Abstract
Excitatory amino acid transporters (EAATs) encompass a class of five transporters with distinct expression in neurons and glia of the central nervous system (CNS). EAATs are mainly recognized for their role in uptake of the amino acid glutamate, the major excitatory neurotransmitter. EAATs-mediated clearance of glutamate released by neurons is vital to maintain proper glutamatergic signalling and to prevent toxic accumulation of this amino acid in the extracellular space. In addition, some EAATs also act as chloride channels or mediate the uptake of cysteine, required to produce the reactive oxygen speciesscavenger glutathione. Given their central role in glutamate homeostasis in the brain, as well as their additional activities, it comes as no surprise that EAAT dysfunctions have been implicated in numerous acute or chronic diseases of the CNS, including ischemic stroke and epilepsy, cerebellar ataxias, amyotrophic lateral sclerosis, Alzheimer’s disease and Huntington’s disease. Here we review the studies in cellular and animal models, as well as in humans that highlight the roles of EAATs in the pathogenesis of these devastating disorders. We also discuss the mechanisms regulating EAATs expression and intracellular trafficking and new exciting possibilities to modulate EAATs and to provide neuroprotection in course of pathologies affecting the CNS.
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Affiliation(s)
- Anna R. Malik
- Nencki Institute of Experimental Biology, 02-093 Warsaw, Poland
- Correspondence:
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Ke T, Sidoryk-Wegrzynowicz M, Pajarillo E, Rizor A, Soares FAA, Lee E, Aschner M. Role of Astrocytes in Manganese Neurotoxicity Revisited. Neurochem Res 2019; 44:2449-2459. [PMID: 31571097 PMCID: PMC7757856 DOI: 10.1007/s11064-019-02881-7] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2019] [Revised: 09/13/2019] [Accepted: 09/16/2019] [Indexed: 12/17/2022]
Abstract
Manganese (Mn) overexposure is a public health concern due to its widespread industrial usage and the risk for environmental contamination. The clinical symptoms of Mn neurotoxicity, or manganism, share several pathological features of Parkinson's disease (PD). Biologically, Mn is an essential trace element, and Mn in the brain is preferentially localized in astrocytes. This review summarizes the role of astrocytes in Mn-induced neurotoxicity, specifically on the role of neurotransmitter recycling, neuroinflammation, and genetics. Mn overexposure can dysregulate astrocytic cycling of glutamine (Gln) and glutamate (Glu), which is the basis for Mn-induced excitotoxic neuronal injury. In addition, reactive astrocytes are important mediators of Mn-induced neuronal damage by potentiating neuroinflammation. Genetic studies, including those with Caenorhabditis elegans (C. elegans) have uncovered several genes associated with Mn neurotoxicity. Though we have yet to fully understand the role of astrocytes in the pathologic changes characteristic of manganism, significant strides have been made over the last two decades in deciphering the role of astrocytes in Mn-induced neurotoxicity and neurodegeneration.
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Affiliation(s)
- Tao Ke
- Department of Molecular Pharmacology, Albert Einstein College of Medicine, Bronx, NY, 10461, USA
| | - Marta Sidoryk-Wegrzynowicz
- Laboratory of Pathoneurochemistry, Department of Neurochemistry, Mossakowski Medical Research Centre, Polish Academy of Sciences, 5 Pawinskiego Street, 02-106, Warsaw, Poland
| | - Edward Pajarillo
- Department of Pharmaceutical Sciences, Florida A&M University, Tallahassee, FL, 32307, USA
| | - Asha Rizor
- Department of Pharmaceutical Sciences, Florida A&M University, Tallahassee, FL, 32307, USA
| | - Félix Alexandre Antunes Soares
- Department of Molecular Pharmacology, Albert Einstein College of Medicine, Bronx, NY, 10461, USA.,Department of Biochemistry and Molecular Biology, Federal University of Santa Maria, Santa Maria, RS, Brazil
| | - Eunsook Lee
- Department of Pharmaceutical Sciences, Florida A&M University, Tallahassee, FL, 32307, USA
| | - Michael Aschner
- Department of Molecular Pharmacology, Albert Einstein College of Medicine, Bronx, NY, 10461, USA. .,Department of Molecular Pharmacology, Albert Einstein College of Medicine, 1300 Morris Park Avenue, Forchheimer Building, Room 209, Bronx, NY, 10461, USA.
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Liu Y, Ding XF, Wang XX, Zou XJ, Li XJ, Liu YY, Li J, Qian XY, Chen JX. Xiaoyaosan exerts antidepressant-like effects by regulating the functions of astrocytes and EAATs in the prefrontal cortex of mice. Altern Ther Health Med 2019; 19:215. [PMID: 31412844 PMCID: PMC6694586 DOI: 10.1186/s12906-019-2613-6] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2018] [Accepted: 07/23/2019] [Indexed: 12/26/2022]
Abstract
Background Mounting evidence indicates that the cerebral cortex is an important physiological system of emotional activity, and its dysfunction may be the main cause of stress. Glutamate is the primary excitatory neurotransmitter in the central nervous system (CNS), which initiates rapid signal transmission in the synapse before its reuptake into the surrounding glia, specifically astrocytes (ASTs). The astrocytic excitatory amino acid transporters 1 (EAAT1) and 2 (EAAT2) are the major transporters that take up synaptic glutamate to maintain optimal extracellular glutamic levels, thus preventing accumulation in the synaptic cleft and ensuing excitotoxicity. Growing evidence has shown that excitotoxicity is associated with depression. Therefore, we hypothesized that the underlying antidepressant-like mechanism of Xiaoyaosan (XYS), a Chinese herbal formula, may be related to the regulation of astrocytic EAATs. Therefore, we studied the antidepressant mechanism of XYS on the basis of EAAT dysfunction in ASTs. Methods Eighty adult C57BL/6 J mice were randomly divided into 4 groups: a control group, a chronic unpredictable mild stress (CUMS) group, a Xiaoyaosan (XYS) treatment group and a fluoxetine hydrochloride (Flu) treatment group. Except for the control group, mice in the other groups all received chronic unpredictable mild stress for 21 days. Mice in the control and CUMS groups received gavage administration with 0.5 mL of normal saline (NS) for 21 days, and mice in the XYS and Flu treatment groups were administered dosages of 0.25 g/kg/d and 2.6 mg/kg/d by gavage. The effects of XYS on the depressive-like behavioral tests, including the open field test (OFT), forced swimming test (FST) and sucrose preference test (SPT), were examined. The glutamate (Glu) concentrations of the prefrontal cortex (PFC) were detected with colorimetry. The morphology of neurons in the PFC was observed by Nissl staining. The expression of glial fibrillary acidic protein (GFAP), NeuN, EAAT1 and EAAT2 proteins in the PFC of mice was detected by using Western blotting and immunohistochemistry. Quantitative real-time PCR (qPCR) was used to detect the expression of the GFAP, NeuN, EAAT1 and EAAT2 genes in the PFC of mice. Results The results of behavioral tests showed that CUMS-induced mice exhibited depressive-like behavior, which could be improved in some tests with XYS and Flu treatment. Immunohistochemistry and Western blot analysis showed that the protein levels of GFAP, NeuN, EAAT1 and EAAT2 in the PFC of CUMS mice were significantly lower than those in the control group, and these changes could be reversed by XYS and Flu. The results of qPCR analysis showed that the expression of GFAP, NeuN, EAAT1 and EAAT2 mRNAs in the PFC of CUMS mice was not significantly changed, with the exception of EAAT2, compared with that of the control group, while the expression of the above mRNAs was significantly higher in the XYS and Flu groups than that in the CUMS group. Conclusion XYS may exert antidepressant-like effects by improving the functions of AST and EAATs and attenuating glutamate-induced neuronal damage in the frontal cortex.
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Tiburcio-Félix R, Cisneros B, Hernández-Kelly LCR, Hernández-Contreras MA, Luna-Herrera J, Rea-Hernández I, Jiménez-Aguilar R, Olivares-Bañuelos TN, Ortega A. Neuronal Nitric Oxide Synthase in Cultured Cerebellar Bergmann Glia: Glutamate-Dependent Regulation. ACS Chem Neurosci 2019; 10:2668-2675. [PMID: 31091406 DOI: 10.1021/acschemneuro.8b00656] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Glutamate exerts its actions through the activation of membrane receptors expressed in neurons and glia cells. The signaling properties of glutamate transporters have been characterized recently, suggesting a complex array of signaling transactions triggered by presynaptic released glutamate. In the cerebellar molecular layer, glutamatergic synapses are surrounded by Bergmann glia cells, compulsory participants of glutamate turnover and supply to neurons. Since a glutamate-dependent increase in cGMP levels has been described in these cells and the nitric oxide-cGMP signaling cascade increases their glutamate uptake activity, we describe here the Bergmann glia expression of neuronal nitric oxide synthetase. An augmentation of neuronal nitric oxide synthase was found upon glutamate exposure. This effect is mediated by glutamate transporters and is related to an increase in the stability of the enzyme. These results strengthen the notion of a complex regulation of glial glutamate uptake that supports neuronal glutamate signaling.
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Affiliation(s)
- Reynaldo Tiburcio-Félix
- Departamento de Genética y Biología Molecular, Centro de Investigación y de Estudios Avanzados del IPN, Apartado Postal 14-740, Ciudad de México 07360, Mexico
| | - Bulmaro Cisneros
- Departamento de Genética y Biología Molecular, Centro de Investigación y de Estudios Avanzados del IPN, Apartado Postal 14-740, Ciudad de México 07360, Mexico
| | - Luisa C. R. Hernández-Kelly
- Departamento de Toxicología, Centro de Investigación y de Estudios Avanzados del IPN, Apartado Postal 14-740, Ciudad de México 07360, Mexico
| | - María A. Hernández-Contreras
- Departamento de Inmunología, Escuela Nacional de Ciencias Biológicas del Instituto Politécnico Nacional, Ciudad de México 11340, México
| | - Julieta Luna-Herrera
- Departamento de Inmunología, Escuela Nacional de Ciencias Biológicas del Instituto Politécnico Nacional, Ciudad de México 11340, México
| | - Ismael Rea-Hernández
- Departamento de Genética y Biología Molecular, Centro de Investigación y de Estudios Avanzados del IPN, Apartado Postal 14-740, Ciudad de México 07360, Mexico
| | - Rosalinda Jiménez-Aguilar
- Unidad de Cuidados Intensivos Pediátricos, Hospital General La Raza Gaudencio González Garza, Unidad de Alta Especialidad Médica (UMAE), Instituto Mexicano del Seguro Social, Ciudad de México 02990, México
| | - Tatiana N. Olivares-Bañuelos
- Instituto de Investigaciones Oceanológicas, Universidad Autónoma de Baja California, Ensenada, Baja California 22860, México
| | - Arturo Ortega
- Departamento de Toxicología, Centro de Investigación y de Estudios Avanzados del IPN, Apartado Postal 14-740, Ciudad de México 07360, Mexico
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Transcriptional Regulation of the Glutamate/GABA/Glutamine Cycle in Adult Glia Controls Motor Activity and Seizures in Drosophila. J Neurosci 2019; 39:5269-5283. [PMID: 31064860 PMCID: PMC6607755 DOI: 10.1523/jneurosci.1833-18.2019] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2018] [Revised: 04/09/2019] [Accepted: 04/11/2019] [Indexed: 01/23/2023] Open
Abstract
The fruitfly Drosophila melanogaster has been extensively used as a genetic model for the maintenance of nervous system's functions. Glial cells are of utmost importance in regulating the neuronal functions in the adult organism and in the progression of neurological pathologies. Through a microRNA-based screen in adult Drosophila glia, we uncovered the essential role of a major glia developmental determinant, repo, in the adult fly. Here, we report that Repo expression is continuously required in adult glia to transcriptionally regulate the highly conserved function of neurotransmitter recycling in both males and females. Transient loss of Repo dramatically shortens fly lifespan, triggers motor deficits, and increases the sensibility to seizures, partly due to the impairment of the glutamate/GABA/glutamine cycle. Our findings highlight the pivotal role of transcriptional regulation of genes involved in the glutamate/GABA/glutamine cycle in glia to control neurotransmitter levels in neurons and their behavioral output. The mechanism identified here in Drosophila exemplifies how adult functions can be modulated at the transcriptional level and suggest an active synchronized regulation of genes involved in the same pathway. The process of neurotransmitter recycling is of essential importance in human epileptic and psychiatric disorders and our findings may thus have important consequences for the understanding of the role that transcriptional regulation of neurotransmitter recycling in astrocytes has in human disease. SIGNIFICANCE STATEMENT Glial cells are an essential support to neurons in adult life and have been involved in a number of neurological disorders. What controls the maintenance and modulation of glial functions in adult life is not fully characterized. Through a miR overexpression screen in adult glia in Drosophila, we identify an essential role in adult glia of repo, which directs glial differentiation during embryonic development. Repo levels modulate, via transcriptional regulation, the ability of glial cells to support neurons in the glutamate/GABA/glutamine cycle. This leads to significant abnormalities in motor behavior as assessed through a novel automated paradigm. Our work points to the importance of transcriptional regulation in adult glia for neurotransmitter recycling, a key process in several human neurological disorders.
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Wang C, Wang Z, Liu W, Ai Z. CD133 promotes the self-renewal capacity of thyroid cancer stem cells through activation of glutamate aspartate transporter SLC1A3 expression. Biochem Biophys Res Commun 2019; 511:87-91. [DOI: 10.1016/j.bbrc.2019.02.023] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2019] [Accepted: 02/05/2019] [Indexed: 12/13/2022]
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Jun YW, Cho SW, Jung J, Huh Y, Kim Y, Kim D, Ahn KH. Frontiers in Probing Alzheimer's Disease Biomarkers with Fluorescent Small Molecules. ACS CENTRAL SCIENCE 2019; 5:209-217. [PMID: 30834309 PMCID: PMC6396189 DOI: 10.1021/acscentsci.8b00951] [Citation(s) in RCA: 52] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/19/2018] [Indexed: 05/13/2023]
Abstract
Alzheimer's disease (AD) is the most common form of dementia. The pathogenesis of the disease is associated with aggregated amyloid-β, hyperphosphorylated tau, a high level of metal ions, abnormal enzyme activities, and reactive astrocytes. This outlook gives an overview of fluorescent small molecules targeting AD biomarkers for ex vivo and in vivo imaging. These chemical imaging probes are categorized based on the potential biomarkers, and their pros and cons are discussed. Guidelines for designing new sensing strategies as well as the desirable properties to be pursued for AD fluorescence imaging are also provided.
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Affiliation(s)
- Yong Woong Jun
- Department
of Chemistry, Pohang University of Science
and Technology (POSTECH), 77 Cheongam-Ro, Nam-Gu, Pohang 37673, Republic
of Korea
| | - Seo Won Cho
- Department
of Chemistry, Pohang University of Science
and Technology (POSTECH), 77 Cheongam-Ro, Nam-Gu, Pohang 37673, Republic
of Korea
| | - Junyang Jung
- Department of Anatomy and Neurobiology,
College of Medicine, Center for Converging
Humanities, and Biomedical Science Institute, Kyung Hee
University, 26 Kyungheedae-Ro, Dongdaemun-Gu, Seoul 02447, Republic of Korea
| | - Youngbuhm Huh
- Department of Anatomy and Neurobiology,
College of Medicine, Center for Converging
Humanities, and Biomedical Science Institute, Kyung Hee
University, 26 Kyungheedae-Ro, Dongdaemun-Gu, Seoul 02447, Republic of Korea
| | - YoungSoo Kim
- Integrated
Science and Engineering Division, Department of Pharmacy, and Yonsei
Institute of Pharmaceutical Sciences, Yonsei
University, 85 Songdogwahak-ro, Yeonsu-gu, Incheon 21983, Republic of Korea
- (Y.K.)
E-mail:
| | - Dokyoung Kim
- Department of Anatomy and Neurobiology,
College of Medicine, Center for Converging
Humanities, and Biomedical Science Institute, Kyung Hee
University, 26 Kyungheedae-Ro, Dongdaemun-Gu, Seoul 02447, Republic of Korea
- (D.K.) E-mail:
| | - Kyo Han Ahn
- Department
of Chemistry, Pohang University of Science
and Technology (POSTECH), 77 Cheongam-Ro, Nam-Gu, Pohang 37673, Republic
of Korea
- (K.H.A.) E-mail:
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Kim J, Pajarillo E, Rizor A, Son DS, Lee J, Aschner M, Lee E. LRRK2 kinase plays a critical role in manganese-induced inflammation and apoptosis in microglia. PLoS One 2019; 14:e0210248. [PMID: 30645642 PMCID: PMC6333340 DOI: 10.1371/journal.pone.0210248] [Citation(s) in RCA: 49] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2018] [Accepted: 12/19/2018] [Indexed: 12/11/2022] Open
Abstract
Long-term exposure to elevated levels of manganese (Mn) causes manganism, a neurodegenerative disorder with Parkinson's disease (PD)-like symptoms. Increasing evidence suggests that leucine-rich repeat kinase 2 (LRRK2), which is highly expressed in microglia and macrophages, contributes to the inflammation and neurotoxicity seen in autosomal dominant and sporadic PD. As gene-environment interactions have emerged as important modulators of PD-associated toxicity, LRRK2 may also mediate Mn-induced inflammation and pathogenesis. In this study, we investigated the role of LRRK2 in Mn-induced toxicity using human microglial cells (HMC3), LRRK2-wild-type (WT) and LRRK2-knockout (KO) RAW264.7 macrophage cells. Results showed that Mn activated LRRK2 kinase by phosphorylation of its serine residue at the 1292 position (S1292) as a marker of its kinase activity in macrophage and microglia, while inhibition with GSK2578215A (GSK) and MLi-2 abolished Mn-induced LRRK2 activation. LRRK2 deletion and its pharmacological inhibition attenuated Mn-induced apoptosis in macrophages and microglia, along with concomitant decreases in the pro-apoptotic Bcl-2-associated X (Bax) protein. LRRK2 deletion also attenuated Mn-induced production of reactive oxygen species (ROS) and the pro-inflammatory cytokine TNF-α. Mn-induced phosphorylation of mitogen-activated protein kinase (MAPK) p38 and ERK signaling proteins was significantly attenuated in LRRK2 KO cells and GSK-treated cells. Moreover, inhibition of MAPK p38 and ERK as well as LRRK2 attenuated Mn-induced oxidative stress and cytotoxicity. These findings suggest that LRRK2 kinase activity plays a critical role in Mn-induced toxicity via downstream activation of MAPK signaling in macrophage and microglia. Collectively, these results suggest that LRRK2 could be a potential molecular target for developing therapeutics to treat Mn-related neurodegenerative disorders.
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Affiliation(s)
- Judong Kim
- Department of Pharmaceutical Sciences, College of Pharmacy, Florida A&M University, Tallahassee, Florida, United States of America
| | - Edward Pajarillo
- Department of Pharmaceutical Sciences, College of Pharmacy, Florida A&M University, Tallahassee, Florida, United States of America
| | - Asha Rizor
- Department of Pharmaceutical Sciences, College of Pharmacy, Florida A&M University, Tallahassee, Florida, United States of America
| | - Deok-Soo Son
- Department of Biochemistry and Cancer Biology, Meharry Medical College, Nashville, Tennessee, United States of America
| | - Jayden Lee
- Department of Speech, Language & Hearing Sciences, Boston University, Boston, Massachusetts, United States of America
| | - Michael Aschner
- Department of Molecular Pharmacology, Albert Einstein College of Medicine, Bronx, New York, United States of America
| | - Eunsook Lee
- Department of Pharmaceutical Sciences, College of Pharmacy, Florida A&M University, Tallahassee, Florida, United States of America
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Baez-Jurado E, Rincón-Benavides MA, Hidalgo-Lanussa O, Guio-Vega G, Ashraf GM, Sahebkar A, Echeverria V, Garcia-Segura LM, Barreto GE. Molecular mechanisms involved in the protective actions of Selective Estrogen Receptor Modulators in brain cells. Front Neuroendocrinol 2019; 52:44-64. [PMID: 30223003 DOI: 10.1016/j.yfrne.2018.09.001] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/01/2018] [Revised: 09/09/2018] [Accepted: 09/12/2018] [Indexed: 02/06/2023]
Abstract
Synthetic selective modulators of the estrogen receptors (SERMs) have shown to protect neurons and glial cells against toxic insults. Among the most relevant beneficial effects attributed to these compounds are the regulation of inflammation, attenuation of astrogliosis and microglial activation, prevention of excitotoxicity and as a consequence the reduction of neuronal cell death. Under pathological conditions, the mechanism of action of the SERMs involves the activation of estrogen receptors (ERs) and G protein-coupled receptor for estrogens (GRP30). These receptors trigger neuroprotective responses such as increasing the expression of antioxidants and the activation of kinase-mediated survival signaling pathways. Despite the advances in the knowledge of the pathways activated by the SERMs, their mechanism of action is still not entirely clear, and there are several controversies. In this review, we focused on the molecular pathways activated by SERMs in brain cells, mainly astrocytes, as a response to treatment with raloxifene and tamoxifen.
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Affiliation(s)
- E Baez-Jurado
- Departamento de Nutrición y Bioquímica, Facultad de Ciencias, Pontificia Universidad Javeriana, Bogotá D.C., Colombia
| | - M A Rincón-Benavides
- Departamento de Nutrición y Bioquímica, Facultad de Ciencias, Pontificia Universidad Javeriana, Bogotá D.C., Colombia
| | - O Hidalgo-Lanussa
- Departamento de Nutrición y Bioquímica, Facultad de Ciencias, Pontificia Universidad Javeriana, Bogotá D.C., Colombia
| | - G Guio-Vega
- Departamento de Nutrición y Bioquímica, Facultad de Ciencias, Pontificia Universidad Javeriana, Bogotá D.C., Colombia
| | - G M Ashraf
- King Fahd Medical Research Center, King Abdulaziz University, Jeddah, Saudi Arabia
| | - A Sahebkar
- Biotechnology Research Center, Pharmaceutical Technology Institute, Mashhad University of Medical Sciences, Mashhad, Iran; Neurogenic Inflammation Research Center, Mashhad University of Medical Sciences, Mashhad, Iran; School of Pharmacy, Mashhad University of Medical Sciences, Mashhad, Iran
| | - V Echeverria
- Universidad San Sebastián, Fac. Cs de la Salud, Lientur 1457, Concepción 4080871, Chile; Research & Development Service, Bay Pines VA Healthcare System, Bay Pines, FL 33744, USA
| | - L M Garcia-Segura
- Instituto Cajal, CSIC, Madrid, Spain; Centro de Investigación Biomédica en Red Fragilidad y Envejecimiento Saludable (CIBERFES), Instituto de Salud Carlos III, Madrid, Spain
| | - G E Barreto
- Departamento de Nutrición y Bioquímica, Facultad de Ciencias, Pontificia Universidad Javeriana, Bogotá D.C., Colombia; Instituto de Ciencias Biomédicas, Universidad Autónoma de Chile, Santiago, Chile.
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Chen ZS, Chan HYE. Transcriptional dysregulation in neurodegenerative diseases: Who tipped the balance of Yin Yang 1 in the brain? Neural Regen Res 2019; 14:1148-1151. [PMID: 30804239 PMCID: PMC6425841 DOI: 10.4103/1673-5374.251193] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Yin Yang 1 (YY1) is a multi-functional transcription factor that regulates gene expression in a range of cell types, including neurons. It controls neuronal differentiation, as well as neuronal specification and migration during the development of the mammalian nervous system. Besides, YY1 also mediates the transcription of genes that are required for neuronal survival. An impairment of the transcriptional function of YY1 causes neuronal death. This review summarizes recent research findings that unveil the dysfunction of YY1 in multiple neurodegenerative disorders. The expression of disease proteins perturbs the function of YY1 via distinct molecular mechanisms, including recruitment to protein aggregates, protein degradation and aberrant nuclear/cytoplasmic shuttling. Understanding the pathogenic roles of YY1 will further broaden our knowledge of the disease mechanisms in distinct neurodegenerative disorders.
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Affiliation(s)
- Zhefan Stephen Chen
- School of Life Sciences, Faculty of Science, The Chinese University of Hong Kong, Hong Kong Special Administration Region, China
| | - Ho Yin Edwin Chan
- School of Life Sciences, Faculty of Science; Gerald Choa Neuroscience Centre, The Chinese University of Hong Kong, Hong Kong Special Administration Region, China
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Developmental Exposure of Mice to T-2 Toxin Increases Astrocytes and Hippocampal Neural Stem Cells Expressing Metallothionein. Neurotox Res 2018; 35:668-683. [DOI: 10.1007/s12640-018-9981-4] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2018] [Revised: 11/07/2018] [Accepted: 11/07/2018] [Indexed: 12/18/2022]
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Johnson J, Pajarillo E, Karki P, Kim J, Son DS, Aschner M, Lee E. Valproic acid attenuates manganese-induced reduction in expression of GLT-1 and GLAST with concomitant changes in murine dopaminergic neurotoxicity. Neurotoxicology 2018; 67:112-120. [PMID: 29778792 PMCID: PMC6441963 DOI: 10.1016/j.neuro.2018.05.001] [Citation(s) in RCA: 36] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2018] [Revised: 05/10/2018] [Accepted: 05/14/2018] [Indexed: 12/31/2022]
Abstract
Exposure to elevated levels of manganese (Mn) causes manganism, a neurological disorder with similar characteristics to those of Parkinson's disease (PD). Valproic acid (VPA), an antiepileptic, is known to inhibit histone deacetylases and exert neuroprotective effects in many experimental models of neurological disorders. In the present study, we investigated if VPA attenuated Mn-induced dopaminergic neurotoxicity and the possible mechanisms involved in VPA's neuroprotection, focusing on modulation of astrocytic glutamate transporters (glutamate aspartate transporter, GLAST and glutamate transporter 1, GLT-1) and histone acetylation in H4 astrocyte culture and mouse models. The results showed that VPA increased promoter activity, mRNA/protein levels of GLAST/GLT-1 and glutamate uptake, and reversed Mn-reduced GLAST/GLT-1 in in vitro astrocyte cultures. VPA also attenuated Mn-induced reduction of GLAST and GLT-1 mRNA/protein levels in midbrain and striatal regions of the mouse brain when VPA (200 mg/kg, i.p., daily, 21 d) was administered 30 min prior to Mn exposure (30 mg/kg, intranasal instillation, daily, 21 d). Importantly, VPA attenuated Mn-induced dopaminergic neuronal damage by reversing Mn-induced decrease of tyrosine hydroxylase (TH) mRNA/protein levels in the nigrostriatal regions. VPA also reversed Mn-induced reduction of histone acetylation in astrocytes as well as mouse brain tissue. Taken together, VPA exerts attenuation against Mn-induced decrease of astrocytic glutamate transporters parallel with reversing Mn-induced dopaminergic neurotoxicity and Mn-reduced histone acetylation. Our findings suggest that VPA could serve as a potential neuroprotectant against Mn neurotoxicity as well as other neurodegenerative diseases associated with excitotoxicity and impaired astrocytic glutamate transporters.
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Affiliation(s)
- James Johnson
- Department of Neuroscience and Pharmacology, Meharry Medical College, Nashville, TN 37208, United States
| | - Edward Pajarillo
- Department of Pharmaceutical Sciences, College of Pharmacy, Florida A&M University, Tallahassee, FL, 32301, United States
| | - Pratap Karki
- Department of Pharmaceutical Sciences, College of Pharmacy, Florida A&M University, Tallahassee, FL, 32301, United States
| | - Judong Kim
- Department of Pharmaceutical Sciences, College of Pharmacy, Florida A&M University, Tallahassee, FL, 32301, United States
| | - Deok-Soo Son
- Department of Biochemistry and Cancer Biology, Meharry Medical College, Nashville, TN, 37208, United States
| | - Michael Aschner
- Department of Molecular Pharmacology, Albert Einstein College of Medicine, Bronx, NY, 10461, United States
| | - Eunsook Lee
- Department of Pharmaceutical Sciences, College of Pharmacy, Florida A&M University, Tallahassee, FL, 32301, United States.
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Laquinimod ameliorates excitotoxic damage by regulating glutamate re-uptake. J Neuroinflammation 2018; 15:5. [PMID: 29304807 PMCID: PMC5756343 DOI: 10.1186/s12974-017-1048-6] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2017] [Accepted: 12/21/2017] [Indexed: 11/10/2022] Open
Abstract
Background Laquinimod is an immunomodulatory drug under clinical investigation for the treatment of the progressive form of multiple sclerosis (MS) with both anti-inflammatory and neuroprotective effects. Excitotoxicity, a prominent pathophysiological feature of MS and of its animal model, experimental autoimmune encephalomyelitis (EAE), involves glutamate transporter (GluT) dysfunction in glial cells. The aim of this study was to assess whether laquinimod might exert direct neuroprotective effects by interfering with the mechanisms of excitotoxicity linked to GluT function impairments in EAE. Methods Osmotic minipumps allowing continuous intracerebroventricular (icv) infusion of laquinimod for 4 weeks were implanted into C57BL/6 mice before EAE induction. EAE cerebella were taken to perform western blot and qPCR experiments. For ex vivo experiments, EAE cerebellar slices were incubated with laquinimod before performing electrophysiology, western blot, and qPCR. Results In vivo treatment with laquinimod attenuated EAE clinical score at the peak of the disease, without remarkable effects on inflammatory markers. In vitro application of laquinimod to EAE cerebellar slices prevented EAE-linked glutamatergic alterations without mitigating astrogliosis and inflammation. Moreover, such treatment induced an increase of Slcla3 mRNA coding for the glial glutamate–aspartate transporter (GLAST) without affecting the protein content. Concomitantly, laquinimod significantly increased the levels of the glial glutamate transporter 1 (GLT-1) protein and pharmacological blockade of GLT-1 function fully abolished laquinimod anti-excitotoxic effect. Conclusions Overall, our results suggest that laquinimod protects against glutamate excitotoxicity of the cerebellum of EAE mice by bursting the expression of glial glutamate transporters, independently of its anti-inflammatory effects.
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Pajarillo E, Johnson J, Kim J, Karki P, Son DS, Aschner M, Lee E. 17β-estradiol and tamoxifen protect mice from manganese-induced dopaminergic neurotoxicity. Neurotoxicology 2017; 65:280-288. [PMID: 29183790 DOI: 10.1016/j.neuro.2017.11.008] [Citation(s) in RCA: 38] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2017] [Revised: 11/20/2017] [Accepted: 11/22/2017] [Indexed: 01/14/2023]
Abstract
Chronic exposure to manganese (Mn) causes neurotoxicity, referred to as manganism, with common clinical features of parkinsonism. 17β-estradiol (E2) and tamoxifen (TX), a selective estrogen receptor modulator (SERM), afford neuroprotection in several neurological disorders, including Parkinson's disease (PD). In the present study, we tested if E2 and TX attenuate Mn-induced neurotoxicity in mice, assessing motor deficit and dopaminergic neurodegeneration. We implanted E2 and TX pellets in the back of the neck of ovariectomized C57BL/6 mice two weeks prior to a single injection of Mn into the striatum. One week later, we assessed locomotor activity and molecular mechanisms by immunohistochemistry, real-time quantitative PCR, western blot and enzymatic biochemical analyses. The results showed that both E2 and TX attenuated Mn-induced motor deficits and reversed the Mn-induced loss of dopaminergic neurons in the substantia nigra. At the molecular level, E2 and TX reversed the Mn-induced decrease of (1) glutamate aspartate transporter (GLAST) and glutamate transporter 1 (GLT-1) mRNA and protein levels; (2) transforming growth factor-α (TGF-α) and estrogen receptor-α (ER-α) protein levels; and (3) catalase (CAT) activity and glutathione (GSH) levels, and Mn-increased (1) malondialdehyde (MDA) levels and (2) the Bax/Bcl-2 ratio. These results indicate that E2 and TX afford protection against Mn-induced neurotoxicity by reversing Mn-reduced GLT1/GLAST as well as Mn-induced oxidative stress. Our findings may offer estrogenic agents as potential candidates for the development of therapeutics to treat Mn-induced neurotoxicity.
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Affiliation(s)
- Edward Pajarillo
- Department of Pharmaceutical Sciences, College of Pharmacy, Florida A&M University, Tallahassee, FL 32301, United States
| | - James Johnson
- Department of Neuroscience and Pharmacology, Meharry Medical College, Nashville, TN 37208, United States
| | - Judong Kim
- Department of Pharmaceutical Sciences, College of Pharmacy, Florida A&M University, Tallahassee, FL 32301, United States
| | - Pratap Karki
- Department of Pharmaceutical Sciences, College of Pharmacy, Florida A&M University, Tallahassee, FL 32301, United States
| | - Deok-Soo Son
- Department of Biochemistry and Cancer Biology, Meharry Medical College Nashville, TN 37208, United States
| | - Michael Aschner
- Department of Molecular Pharmacology, Albert Einstein College of Medicine Bronx, NY 10461, United States
| | - Eunsook Lee
- Department of Pharmaceutical Sciences, College of Pharmacy, Florida A&M University, Tallahassee, FL 32301, United States.
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Asai Y, Tanaka H, Nadai M, Katoh M. Status Epilepticus Decreases Brain Cytochrome P450 2D4 Expression in Rats. J Pharm Sci 2017; 107:975-978. [PMID: 29175413 DOI: 10.1016/j.xphs.2017.11.010] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2017] [Revised: 11/09/2017] [Accepted: 11/16/2017] [Indexed: 01/09/2023]
Abstract
Status epilepticus (SE) is a life-threatening neurological emergency characterized by frequent seizures. The present study aims at elucidating the effect of SE on CYP2D4 expression in the rat brain. To create a rat model of SE, Sprague-Dawley rats were intraperitoneally administered 10 mg/kg kainic acid. The CYP2D4 mRNA levels in the cortex and hippocampus of the SE rats were decreased by 0.38- and 0.39-fold, respectively. The protein level of octamer transcription factor 1 (Oct-1), which is involved in the transcriptional activation of CYP2D4 by binding to the CYP2D4 regulatory element, was also attenuated by 0.64- and 0.51-fold in these regions of the SE rat, suggesting that a reduction in Oct-1 may be involved in the CYP2D4 suppression. Yin yang 1 can function as a cofactor of histone deacetylase 1 and inhibit the binding of Oct-1 to the CYP2D4 regulatory element. The coimmunoprecipitation assay revealed that the interaction between yin yang 1 and histone deacetylase 1 in the cortex and hippocampus was enhanced during SE, indicating that this interaction is also responsible for the CYP2D4 suppression. This study clarified that SE led to a decrease in the expression of CYP2D4, thus altering the pharmacokinetics and efficacy of the drugs in the brain.
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Affiliation(s)
- Yuki Asai
- Pharmaceutics, Faculty of Pharmacy, Meijo University, 150 Yagotoyama, Tempaku-ku, Nagoya 468-8503, Japan
| | - Hatsuna Tanaka
- Pharmaceutics, Faculty of Pharmacy, Meijo University, 150 Yagotoyama, Tempaku-ku, Nagoya 468-8503, Japan
| | - Masayuki Nadai
- Pharmaceutics, Faculty of Pharmacy, Meijo University, 150 Yagotoyama, Tempaku-ku, Nagoya 468-8503, Japan
| | - Miki Katoh
- Pharmaceutics, Faculty of Pharmacy, Meijo University, 150 Yagotoyama, Tempaku-ku, Nagoya 468-8503, Japan.
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Karki P, Hong P, Johnson J, Pajarillo E, Son DS, Aschner M, Lee EY. Arundic Acid Increases Expression and Function of Astrocytic Glutamate Transporter EAAT1 Via the ERK, Akt, and NF-κB Pathways. Mol Neurobiol 2017; 55:5031-5046. [PMID: 28812276 PMCID: PMC5964991 DOI: 10.1007/s12035-017-0709-x] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2017] [Accepted: 08/02/2017] [Indexed: 12/22/2022]
Abstract
Glutamate is the major excitatory neurotransmitter in the brain, but excessive synaptic glutamate must be removed to prevent excitotoxic injury and death. Two astrocytic glutamate transporters, excitatory amino acid transporter (EAAT) 1 and 2, play a major role in eliminating excess glutamate from the synapse. Dysregulation of EAAT1 contributes to the pathogenesis of multiple neurological disorders, such as Alzheimer's disease (AD), ataxia, traumatic brain injuries, and glaucoma. In the present study, we investigated the effect of arundic acid on EAAT1 to determine its efficacy in enhancing the expression and function of EAAT1, and its possible mechanisms of action. The studies were carried out in human astrocyte H4 cells as well as in human primary astrocytes. Our findings show that arundic acid upregulated EAAT1 expression at the transcriptional level by activating nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB). Arundic acid increased astrocytic EAAT1 promoter activity, messenger RNA (mRNA)/protein levels, and glutamate uptake, while pharmacological inhibition of NF-κB or mutation on NF-κB binding sites in the EAAT1 promoter region abrogated these effects. Arundic acid increased NF-κB reporter activity and induced NF-κB nuclear translocation as well as its bindings to the EAAT1 promoter. Furthermore, arundic acid activated the Akt and ERK signaling pathways to enhance EAAT1 mRNA/protein levels. Finally, arundic acid attenuated manganese-induced decrease in EAAT1 expression by inhibiting expression of the transcription factor Ying Yang 1 (YY1). These results demonstrate that arundic acid increases the expression and function of EAAT1 via the Akt, ERK, and NF-κB signaling pathways, and reverses Mn-induced EAAT1 repression by inhibiting the Mn-induced YY1 activation.
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Affiliation(s)
- Pratap Karki
- Department of Pharmaceutical Sciences, College of Pharmacy, Florida A&M University, Tallahassee, FL, 32307, USA
| | - Peter Hong
- Department of Physiology, Meharry Medical College, Nashville, TN, 37208, USA
| | - James Johnson
- Department of Physiology, Meharry Medical College, Nashville, TN, 37208, USA
| | - Edward Pajarillo
- Department of Pharmaceutical Sciences, College of Pharmacy, Florida A&M University, Tallahassee, FL, 32307, USA
| | - Deok-Soo Son
- Department of Physiology, Meharry Medical College, Nashville, TN, 37208, USA
| | - Michael Aschner
- Department of Molecular Pharmacology, Albert Einstein College of Medicine, Bronx, NY, 10461, USA
| | - Eunsook Y Lee
- Department of Pharmaceutical Sciences, College of Pharmacy, Florida A&M University, Tallahassee, FL, 32307, USA.
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Spencer S, Kalivas PW. Glutamate Transport: A New Bench to Bedside Mechanism for Treating Drug Abuse. Int J Neuropsychopharmacol 2017; 20:797-812. [PMID: 28605494 PMCID: PMC5632313 DOI: 10.1093/ijnp/pyx050] [Citation(s) in RCA: 42] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/12/2017] [Accepted: 06/09/2017] [Indexed: 02/06/2023] Open
Abstract
Drug addiction has often been described as a "hijacking" of the brain circuits involved in learning and memory. Glutamate is the principal excitatory neurotransmitter in the brain, and its contribution to synaptic plasticity and learning processes is well established in animal models. Likewise, over the past 20 years the addiction field has ascribed a critical role for glutamatergic transmission in the development of addiction. Chronic drug use produces enduring neuroadaptations in corticostriatal projections that are believed to contribute to a maladaptive deficit in inhibitory control over behavior. Much of this research focuses on the role played by ionotropic glutamate receptors directly involved in long-term potentiation and depression or metabotropic receptors indirectly modulating synaptic plasticity. Importantly, the balance between glutamate release and clearance tightly regulates the patterned activation of these glutamate receptors, emphasizing an important role for glutamate transporters in maintaining extracellular glutamate levels. Five excitatory amino acid transporters participate in active glutamate reuptake. Recent evidence suggests that these glutamate transporters can be modulated by chronic drug use at a variety of levels. In this review, we synopsize the evidence and mechanisms associated with drug-induced dysregulation of glutamate transport. We then summarize the preclinical and clinical data suggesting that glutamate transporters offer an effective target for the treatment of drug addiction. In particular, we focus on the role that altered glutamate transporters have in causing drug cues and contexts to develop an intrusive quality that guides maladaptive drug seeking behaviors.
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Affiliation(s)
- Sade Spencer
- Department of Neurosciences, Medical University of South Carolina, Charleston, South Carolina.,Correspondence: Sade Spencer, PhD, Medical University of South Carolina, 173 Ashley Avenue, BSB, 403- MSC 510, Charleston, SC 29425 ()
| | - Peter W Kalivas
- Department of Neurosciences, Medical University of South Carolina, Charleston, South Carolina.
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Johnson J, Pajarillo EAB, Taka E, Reams R, Son DS, Aschner M, Lee E. Valproate and sodium butyrate attenuate manganese-decreased locomotor activity and astrocytic glutamate transporters expression in mice. Neurotoxicology 2017; 64:230-239. [PMID: 28610743 DOI: 10.1016/j.neuro.2017.06.007] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2017] [Revised: 06/07/2017] [Accepted: 06/09/2017] [Indexed: 12/19/2022]
Abstract
Manganese (Mn) is an essential trace element, but chronic overexposure to this metal, either environmentally or occupationally may cause manganism, a disease analogous to Parkinson's disease. Inhibitors of histone deacetylases, such as valproic acid (VPA) and sodium butyrate (NaB) exert neuroprotective effects in various animal models of neurological disorders. Thus, the present study investigated whether VPA or NaB prevent Mn-induced neurotoxicity by assessing locomotor activities and expression of astrocytic glutamate transporters, glutamate transporter 1 (GLT-1) and glutamate aspartate transporter (GLAST), in C57BL/6 mice. C57BL/6 mice were pretreated with VPA (200mg/kg, i.p.) or NaB (1200mg/kg, i.p.) prior to intranasal instillation of Mn (30mg/kg) continually for 21days, followed by open-field and rota-rod behavioral tests and analyses of astrocytic glutamate transporters GLT-1 and GLAST protein/mRNA levels. The results showed that Mn significantly decreased locomotor activity as determined by total distance travelled, stereotypic and ambulatory counts. Mn also significantly decreased rota-rod activity reflecting altered motor coordination. Pretreatment with VPA and NaB with Mn reversed the effects of Mn on the locomotor activity and motor coordination. VPA and NaB also attenuated the Mn-induced decrease in GLT-1 and GLAST mRNA and protein levels in the cerebral cortical and cerebellar regions of mice. These results suggest that VPA and NaB exert protective effects against Mn toxicity seem in vitro are also shown in vivo. VPA and NaB pretreatment in mice enhancing astrocytic glutamate transporter GLT-1 expression as well as locomotor activities. Future research endeavors are warranted to determine if the therapeutic potential of VPA and NaB is via common molecular mechanism, namely, inhibition of histone deacetylases.
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Affiliation(s)
- James Johnson
- Department of Neuroscience and Pharmacology, Meharry Medical College, Nashville, TN 37208, USA
| | - Edward Alain B Pajarillo
- Department of Pharmaceutical Sciences, College of Pharmacy, Florida A&M University, Tallahassee, FL 32301, USA
| | - Equar Taka
- Department of Pharmaceutical Sciences, College of Pharmacy, Florida A&M University, Tallahassee, FL 32301, USA
| | - Romonia Reams
- Department of Pharmaceutical Sciences, College of Pharmacy, Florida A&M University, Tallahassee, FL 32301, USA
| | - Deok-Soo Son
- Department of Biochemistry and Cancer Biology, Meharry Medical College, Nashville, TN 37208, USA
| | - Michael Aschner
- Department of Molecular Pharmacology, Albert Einstein College of Medicine, Bronx, NY 10461, USA
| | - Eunsook Lee
- Department of Pharmaceutical Sciences, College of Pharmacy, Florida A&M University, Tallahassee, FL 32301, USA.
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