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Alexander JM, Vazquez-Ramirez L, Lin C, Antonoudiou P, Maguire J, Wagner F, Jacob MH. Inhibition of GSK3α,β rescues cognitive phenotypes in a preclinical mouse model of CTNNB1 syndrome. EMBO Mol Med 2024; 16:2109-2131. [PMID: 39103699 PMCID: PMC11393422 DOI: 10.1038/s44321-024-00110-5] [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: 07/18/2023] [Revised: 07/12/2024] [Accepted: 07/17/2024] [Indexed: 08/07/2024] Open
Abstract
CTNNB1 syndrome is a rare monogenetic disorder caused by CTNNB1 de novo pathogenic heterozygous loss-of-function variants that result in cognitive and motor disabilities. Treatment is currently lacking; our study addresses this critical need. CTNNB1 encodes β-catenin which is essential for normal brain function via its dual roles in cadherin-based synaptic adhesion complexes and canonical Wnt signal transduction. We have generated a Ctnnb1 germline heterozygous mouse line that displays cognitive and motor deficits, resembling key features of CTNNB1 syndrome in humans. Compared with wild-type littermates, Ctnnb1 heterozygous mice also exhibit decreases in brain β-catenin, β-catenin association with N-cadherin, Wnt target gene expression, and Na/K ATPases, key regulators of changes in ion gradients during high activity. Consistently, hippocampal neuron functional properties and excitability are altered. Most important, we identify a highly selective inhibitor of glycogen synthase kinase (GSK)3α,β that significantly normalizes the phenotypes to closely meet wild-type littermate levels. Our data provide new insights into brain molecular and functional changes, and the first evidence for an efficacious treatment with therapeutic potential for individuals with CTNNB1 syndrome.
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Affiliation(s)
- Jonathan M Alexander
- Tufts University School of Biomedical Sciences, Department of Neuroscience, Boston, MA, 02111, USA
| | - Leeanne Vazquez-Ramirez
- Tufts University School of Biomedical Sciences, Department of Neuroscience, Boston, MA, 02111, USA
| | - Crystal Lin
- Tufts University School of Biomedical Sciences, Department of Neuroscience, Boston, MA, 02111, USA
| | - Pantelis Antonoudiou
- Tufts University School of Biomedical Sciences, Department of Neuroscience, Boston, MA, 02111, USA
| | - Jamie Maguire
- Tufts University School of Biomedical Sciences, Department of Neuroscience, Boston, MA, 02111, USA
| | - Florence Wagner
- The Broad Institute of MIT and Harvard, Center for the Development of Therapeutics, Cambridge, MA, 02142, USA
- Photys Therapeutics, Waltham, MA, USA
| | - Michele H Jacob
- Tufts University School of Biomedical Sciences, Department of Neuroscience, Boston, MA, 02111, USA.
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2
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Guo J, Yang WT, Mai FY, Liang JR, Luo J, Zhou MC, Yu DD, Wang YL, Li CG. Unravelling oncosis: morphological and molecular insights into a unique cell death pathway. Front Immunol 2024; 15:1450998. [PMID: 39281670 PMCID: PMC11393741 DOI: 10.3389/fimmu.2024.1450998] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2024] [Accepted: 08/07/2024] [Indexed: 09/18/2024] Open
Abstract
Programmed cell death (PCD) is a fundamental biological process for maintaining cellular equilibrium and regulating development, health, and disease across all living organisms. Among the various types of PCD, apoptosis plays a pivotal role in numerous diseases, notably cancer. Cancer cells frequently develop mechanisms to evade apoptosis, increasing resistance to standard chemotherapy treatments. This resistance has prompted extensive research into alternative mechanisms of programmed cell death. One such pathway is oncosis, characterized by significant energy consumption, cell swelling, dilation of the endoplasmic reticulum, mitochondrial swelling, and nuclear chromatin aggregation. Recent research suggests that oncosis can impact conditions such as chemotherapeutic cardiotoxicity, myocardial ischemic injury, stroke, and cancer, mediated by specific oncosis-related proteins. In this review, we provide a detailed examination of the morphological and molecular features of oncosis and discuss various natural or small molecule compounds that can induce this type of cell death. Additionally, we summarize the current understanding of the molecular mechanisms underlying oncosis and its role in both normal physiology and pathological conditions. These insights aim to illuminate future research directions and propose innovative strategies for leveraging oncosis as a therapeutic tool against human diseases and cancer resistance.
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Affiliation(s)
- Jie Guo
- Department of Rehabilitation Medicine, Shenzhen Second People's Hospital, Shenzhen, China
- Guangdong Key Laboratory for Biomedical Measurements and Ultrasound Imaging, National-Regional Key Technology Engineering Laboratory for Medical Ultrasound, School of Biomedical Engineering, Shenzhen University Medical School, Shenzhen, China
| | - Wen-Tao Yang
- Pain Department of Huazhong University of Science and Technology Union Shenzhen Hospital (Nanshan Hospital), Shenzhen, China
| | - Feng-Yi Mai
- Department of Human Cell Biology and Genetics, Southern University of Science and Technology School of Medicine, Shenzhen, China
| | - Jing-Rong Liang
- Pain Department of Huazhong University of Science and Technology Union Shenzhen Hospital (Nanshan Hospital), Shenzhen, China
| | - Jiao Luo
- Department of Rehabilitation Medicine, Shenzhen Second People's Hospital, Shenzhen, China
| | - Ming-Chao Zhou
- Department of Rehabilitation Medicine, Shenzhen Second People's Hospital, Shenzhen, China
| | - Dong-Dong Yu
- Department of Rehabilitation Medicine, Shenzhen Second People's Hospital, Shenzhen, China
| | - Yu-Long Wang
- Department of Rehabilitation Medicine, Shenzhen Second People's Hospital, Shenzhen, China
- Guangdong Key Laboratory for Biomedical Measurements and Ultrasound Imaging, National-Regional Key Technology Engineering Laboratory for Medical Ultrasound, School of Biomedical Engineering, Shenzhen University Medical School, Shenzhen, China
| | - Chen-Guang Li
- Pain Department of Huazhong University of Science and Technology Union Shenzhen Hospital (Nanshan Hospital), Shenzhen, China
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3
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Liu YB, Arystarkhova E, Sacino AN, Szabari MV, Lutz CM, Terrey M, Morsci NS, Jakobs TC, Lykke-Hartmann K, Brashear A, Napoli E, Sweadner KJ. Phenotype Distinctions in Mice Deficient in the Neuron-Specific α3 Subunit of Na,K-ATPase: Atp1a3 tm1Ling/+ and Atp1a3 +/D801Y. eNeuro 2024; 11:ENEURO.0101-24.2024. [PMID: 39111836 PMCID: PMC11360364 DOI: 10.1523/eneuro.0101-24.2024] [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: 03/08/2024] [Revised: 07/24/2024] [Accepted: 07/25/2024] [Indexed: 08/30/2024] Open
Abstract
ATP1A3 is a Na,K-ATPase gene expressed specifically in neurons in the brain. Human mutations are dominant and produce an unusually wide spectrum of neurological phenotypes, most notably rapid-onset dystonia parkinsonism (RDP) and alternating hemiplegia of childhood (AHC). Here we compared heterozygotes of two mouse lines, a line with little or no expression (Atp1a3tm1Ling/+) and a knock-in expressing p.Asp801Tyr (D801Y, Atp1a3 +/D801Y). Both mouse lines had normal lifespans, but Atp1a3 +/D801Y had mild perinatal mortality contrasting with D801N mice (Atp1a3 +/D801N), which had high mortality. The phenotypes of Atp1a3tm1Ling/+ and Atp1a3 +/D801Y were different, and testing of each strain was tailored to its symptom range. Atp1a3tm1Ling/+ mice displayed little at baseline, but repeated ethanol intoxication produced hyperkinetic motor abnormalities not seen in littermate controls. Atp1a3 +/D801Y mice displayed robust phenotypes: hyperactivity, diminished posture consistent with hypotonia, and deficiencies in beam walk and wire hang tests. Symptoms also included qualitative motor abnormalities that are not well quantified by conventional tests. Paradoxically, Atp1a3 +/D801Y showed sustained better performance than wild type on the accelerating rotarod. Atp1a3 +/D801Y mice were overactive in forced swimming and afterward had intense shivering, transient dystonic postures, and delayed recovery. Remarkably, Atp1a3 +/D801Y mice were refractory to ketamine anesthesia, which elicited hyperactivity and dyskinesia even at higher dose. Neither mouse line exhibited fixed dystonia (typical of RDP patients), spontaneous paroxysmal weakness (typical of AHC patients), or seizures but had consistent, measurable neurological abnormalities. A gradient of variation supports the importance of studying multiple Atp1a3 mutations in animal models to understand the roles of this gene in human disease.
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Affiliation(s)
- Yi Bessie Liu
- Department of Neurosurgery, Massachusetts General Hospital, Boston, Massachusetts 02114
| | - Elena Arystarkhova
- Department of Neurosurgery, Massachusetts General Hospital, Boston, Massachusetts 02114
- Harvard Medical School, Boston, Massachusetts 02115
| | - Amanda N Sacino
- Department of Neurosurgery, Massachusetts General Hospital, Boston, Massachusetts 02114
| | - Margit V Szabari
- Department Anesthesia, Massachusetts General Hospital, Boston, Massachusetts 02114
| | | | | | | | - Tatjana C Jakobs
- Harvard Medical School, Boston, Massachusetts 02115
- Department of Ophthalmology, Massachusetts Eye and Ear Infirmary/Schepens Eye Research Institute, Harvard Medical School, Boston, Massachusetts 02114
| | | | - Allison Brashear
- Department of Neurology, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, Buffalo, New York 14203
| | - Elenora Napoli
- Department of Neurology, University of California Davis School of Medicine, Sacramento, California 95817
| | - Kathleen J Sweadner
- Department of Neurosurgery, Massachusetts General Hospital, Boston, Massachusetts 02114
- Harvard Medical School, Boston, Massachusetts 02115
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4
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Haj Mohammad Hassani B, Malekzadeh K. The lethal homozygous variant in the ATP1A2 gene is associated with FARIMPD syndrome phenotypes in newborns. Neurogenetics 2024:10.1007/s10048-024-00775-7. [PMID: 39046620 DOI: 10.1007/s10048-024-00775-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2024] [Accepted: 07/19/2024] [Indexed: 07/25/2024]
Abstract
FARIMPD (Fetal akinesia, respiratory insufficiency, microcephaly, polymicrogyria, and dysmorphic facies) syndrome is a severe condition caused by ATP1A2 gene variants. The syndrome's novelty and rarity have limited its clinical and molecular knowledge. This research tries to provide new insight by investigating the cause of the early deaths due to FARIMPD syndrome in a particular family and reviewing previous studies. DNA and RNA were extracted from the blood samples of newborns and their parents, followed by whole exome sequencing and segregation analysis. A pathogenic homozygous nonsense variant (c.1234C > T: p.Arg412*) in the ATP1A2 gene was found in newborns. This variant is reported as homozygous for the first time. The migraine symptoms were the result of the heterozygous state of this particular variant, which supported the dominant inheritance pattern of this disease. Real-time PCR was used to analyze ATP1A2 gene expression in the newborns compared to parents and control subjects. The expression analysis also showed significant mRNA degradation in the newborns compared to heterozygous and healthy individuals, due to Nonsense-mediated mRNA Decay phenomena. Our study describes an ATP1A2 nonsense variant (c.1234C > T) that appears compatible with infant survival in the heterozygous and compound heterozygous states but is lethal in the homozygous state.
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Affiliation(s)
- Behzad Haj Mohammad Hassani
- Department of Medical Genetics, Faculty of Medicine, Hormozgan University of Medical Sciences, Bandar Abbas, Iran
| | - Kianoosh Malekzadeh
- Department of Medical Genetics, Faculty of Medicine, Hormozgan University of Medical Sciences, Bandar Abbas, Iran.
- Molecular Medicine Research Center, Hormozgan Health Institute, Hormozgan University of Medical Sciences, Bandar Abbas, Iran.
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5
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Furukawa S, Kato M, Nomura T, Sumitomo N, Yoneno S, Nakashima M, Saitsu H. Novel compound heterozygous ATP1A2 variants in a patient with fetal akinesia/hypokinesia sequence. Am J Med Genet A 2024; 194:e63453. [PMID: 37870493 DOI: 10.1002/ajmg.a.63453] [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: 07/31/2023] [Revised: 10/10/2023] [Accepted: 10/12/2023] [Indexed: 10/24/2023]
Abstract
ATP1A2 encodes a subunit of sodium/potassium-transporting adenosine triphosphatase (Na+ /K+ -ATPase). Heterozygous pathogenic variants of ATP1A2 cause familial hemiplegic migraine, alternating hemiplegia of childhood, and developmental and epileptic encephalopathy. Biallelic loss-of-function variants in ATP1A2 lead to fetal akinesia, respiratory insufficiency, microcephaly, polymicrogyria, and dysmorphic facies, resulting in fetal death. Here, we describe a patient with compound heterozygous ATP1A2 variants consisting of missense and nonsense variants. He survived after birth with brain malformations and the fetal akinesia/hypokinesia sequence. We report a novel type of compound heterozygous variant that might extend the disease spectrum of ATP1A2.
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Affiliation(s)
- Shogo Furukawa
- Department of Biochemistry, Hamamatsu University School of Medicine, Hamamatsu, Japan
| | - Mitsuhiro Kato
- Department of Pediatrics, Showa University School of Medicine, Tokyo, Japan
| | - Toshihiro Nomura
- Department of Pediatrics, Kawaguchi Municipal Medical Center, Saitama, Japan
| | - Noriko Sumitomo
- Department of Child Neurology, National Center of Neurology and Psychiatry, Tokyo, Japan
| | - Shota Yoneno
- Department of Child Neurology, National Center of Neurology and Psychiatry, Tokyo, Japan
| | - Mitsuko Nakashima
- Department of Biochemistry, Hamamatsu University School of Medicine, Hamamatsu, Japan
| | - Hirotomo Saitsu
- Department of Biochemistry, Hamamatsu University School of Medicine, Hamamatsu, Japan
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6
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Pietrobon D, Conti F. Astrocytic Na +, K + ATPases in physiology and pathophysiology. Cell Calcium 2024; 118:102851. [PMID: 38308916 DOI: 10.1016/j.ceca.2024.102851] [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: 12/13/2023] [Revised: 01/26/2024] [Accepted: 01/26/2024] [Indexed: 02/05/2024]
Abstract
The Na+, K+ ATPases play a fundamental role in the homeostatic functions of astrocytes. After a brief historic prologue and discussion of the subunit composition and localization of the astrocytic Na+, K+ ATPases, the review focuses on the role of the astrocytic Na+, K+ pumps in extracellular K+ and glutamate homeostasis, intracellular Na+ and Ca2+ homeostasis and signaling, regulation of synaptic transmission and neurometabolic coupling between astrocytes and neurons. Loss-of-function mutations in the gene encoding the astrocytic α2 Na+, K+ ATPase cause a rare monogenic form of migraine with aura (familial hemiplegic migraine type 2). On the other hand, the α2 Na+, K+ ATPase is upregulated in spinal cord and brain samples from amyotrophic lateral sclerosis and Alzheimer disease patients, respectively. In the last part, the review focuses on i) the migraine relevant phenotypes shown by familial hemiplegic migraine type 2 knock-in mice with 50 % reduced expression of the astrocytic α2 Na+, K+ ATPase and the insights into the pathophysiology of migraine obtained from these genetic mouse models, and ii) the evidence that upregulation of the astrocytic α2 Na+, K+ ATPase in mouse models of amyotrophic lateral sclerosis and Alzheimer disease promotes neuroinflammation and contributes to progressive neurodegeneration.
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Affiliation(s)
- Daniela Pietrobon
- Department of Biomedical Sciences and Padova Neuroscience Center (PNC), University of Padova, Padova 35131, Italy.
| | - Fiorenzo Conti
- Section of Neuroscience and Cell Biology, Department of Experimental and Clinical Medicine, Università Politecnica delle Marche, Ancona, Italy; Center for Neurobiology of Aging, IRCCS INRCA, Ancona, Italy.
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7
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Frankel E, Podder A, Sharifi M, Pillai R, Belnap N, Ramsey K, Dodson J, Venugopal P, Brzezinski M, Llaci L, Gerald B, Mills G, Sanchez-Castillo M, Balak CD, Szelinger S, Jepsen WM, Siniard AL, Richholt R, Naymik M, Schrauwen I, Craig DW, Piras IS, Huentelman MJ, Schork NJ, Narayanan V, Rangasamy S. Genetic and Protein Network Underlying the Convergence of Rett-Syndrome-like (RTT-L) Phenotype in Neurodevelopmental Disorders. Cells 2023; 12:1437. [PMID: 37408271 DOI: 10.3390/cells12101437] [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: 02/07/2023] [Revised: 04/20/2023] [Accepted: 04/29/2023] [Indexed: 07/07/2023] Open
Abstract
Mutations of the X-linked gene encoding methyl-CpG-binding protein 2 (MECP2) cause classical forms of Rett syndrome (RTT) in girls. A subset of patients who are recognized to have an overlapping neurological phenotype with RTT but are lacking a mutation in a gene that causes classical or atypical RTT can be described as having a 'Rett-syndrome-like phenotype (RTT-L). Here, we report eight patients from our cohort diagnosed as having RTT-L who carry mutations in genes unrelated to RTT. We annotated the list of genes associated with RTT-L from our patient cohort, considered them in the light of peer-reviewed articles on the genetics of RTT-L, and constructed an integrated protein-protein interaction network (PPIN) consisting of 2871 interactions connecting 2192 neighboring proteins among RTT- and RTT-L-associated genes. Functional enrichment analysis of RTT and RTT-L genes identified a number of intuitive biological processes. We also identified transcription factors (TFs) whose binding sites are common across the set of RTT and RTT-L genes and appear as important regulatory motifs for them. Investigation of the most significant over-represented pathway analysis suggests that HDAC1 and CHD4 likely play a central role in the interactome between RTT and RTT-L genes.
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Affiliation(s)
- Eric Frankel
- Neurogenomics Division, Translational Genomics Research Institute (TGen), Phoenix, AZ 85004, USA
| | - Avijit Podder
- Quantitative Medicine Division, Translational Genomics Research Institute (TGen), Phoenix, AZ 85004, USA
| | - Megan Sharifi
- Neurogenomics Division, Translational Genomics Research Institute (TGen), Phoenix, AZ 85004, USA
| | - Roshan Pillai
- Neurogenomics Division, Translational Genomics Research Institute (TGen), Phoenix, AZ 85004, USA
| | - Newell Belnap
- Neurogenomics Division, Translational Genomics Research Institute (TGen), Phoenix, AZ 85004, USA
- Center for Rare Childhood Disorders (C4RCD), Translational Genomics Research Institute (TGen), Phoenix, AZ 85004, USA
| | - Keri Ramsey
- Center for Rare Childhood Disorders (C4RCD), Translational Genomics Research Institute (TGen), Phoenix, AZ 85004, USA
| | - Julius Dodson
- Neurogenomics Division, Translational Genomics Research Institute (TGen), Phoenix, AZ 85004, USA
| | - Pooja Venugopal
- Neurogenomics Division, Translational Genomics Research Institute (TGen), Phoenix, AZ 85004, USA
| | - Molly Brzezinski
- Neurogenomics Division, Translational Genomics Research Institute (TGen), Phoenix, AZ 85004, USA
| | - Lorida Llaci
- Neurogenomics Division, Translational Genomics Research Institute (TGen), Phoenix, AZ 85004, USA
- Quantitative Medicine Division, Translational Genomics Research Institute (TGen), Phoenix, AZ 85004, USA
| | - Brittany Gerald
- Neurogenomics Division, Translational Genomics Research Institute (TGen), Phoenix, AZ 85004, USA
| | - Gabrielle Mills
- Neurogenomics Division, Translational Genomics Research Institute (TGen), Phoenix, AZ 85004, USA
| | - Meredith Sanchez-Castillo
- Center for Rare Childhood Disorders (C4RCD), Translational Genomics Research Institute (TGen), Phoenix, AZ 85004, USA
| | - Chris D Balak
- Neurogenomics Division, Translational Genomics Research Institute (TGen), Phoenix, AZ 85004, USA
| | - Szabolcs Szelinger
- Neurogenomics Division, Translational Genomics Research Institute (TGen), Phoenix, AZ 85004, USA
| | - Wayne M Jepsen
- Neurogenomics Division, Translational Genomics Research Institute (TGen), Phoenix, AZ 85004, USA
| | - Ashley L Siniard
- Neurogenomics Division, Translational Genomics Research Institute (TGen), Phoenix, AZ 85004, USA
| | - Ryan Richholt
- Neurogenomics Division, Translational Genomics Research Institute (TGen), Phoenix, AZ 85004, USA
| | - Marcus Naymik
- Neurogenomics Division, Translational Genomics Research Institute (TGen), Phoenix, AZ 85004, USA
| | - Isabelle Schrauwen
- Center for Statistical Genetics, Department of Neurology, Gertrude H. Sergievsky Center, Columbia University Medical Center, New York, NY 10032, USA
| | - David W Craig
- Department of Translational Genomics, University of Southern California, Los Angeles, CA 90033, USA
| | - Ignazio S Piras
- Neurogenomics Division, Translational Genomics Research Institute (TGen), Phoenix, AZ 85004, USA
| | - Matthew J Huentelman
- Neurogenomics Division, Translational Genomics Research Institute (TGen), Phoenix, AZ 85004, USA
- Quantitative Medicine Division, Translational Genomics Research Institute (TGen), Phoenix, AZ 85004, USA
| | - Nicholas J Schork
- Quantitative Medicine Division, Translational Genomics Research Institute (TGen), Phoenix, AZ 85004, USA
- City of Hope National Medical Center, Duarte, CA 91010, USA
| | - Vinodh Narayanan
- Neurogenomics Division, Translational Genomics Research Institute (TGen), Phoenix, AZ 85004, USA
- Center for Rare Childhood Disorders (C4RCD), Translational Genomics Research Institute (TGen), Phoenix, AZ 85004, USA
| | - Sampathkumar Rangasamy
- Neurogenomics Division, Translational Genomics Research Institute (TGen), Phoenix, AZ 85004, USA
- Center for Rare Childhood Disorders (C4RCD), Translational Genomics Research Institute (TGen), Phoenix, AZ 85004, USA
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8
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Palma-Lara I, García Alonso-Themann P, Pérez-Durán J, Godínez-Aguilar R, Bonilla-Delgado J, Gómez-Archila D, Espinosa-García AM, Nolasco-Quiroga M, Victoria-Acosta G, López-Ornelas A, Serrano-Bello JC, Olguín-García MG, Palacios-Reyes C. Potential Role of Protein Kinase FAM20C on the Brain in Raine Syndrome, an In Silico Analysis. Int J Mol Sci 2023; 24:ijms24108904. [PMID: 37240249 DOI: 10.3390/ijms24108904] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2023] [Revised: 05/04/2023] [Accepted: 05/05/2023] [Indexed: 05/28/2023] Open
Abstract
FAM20C (family with sequence similarity 20, member C) is a serine/threonine-specific protein kinase that is ubiquitously expressed and mainly associated with biomineralization and phosphatemia regulation. It is mostly known due to pathogenic variants causing its deficiency, which results in Raine syndrome (RNS), a sclerosing bone dysplasia with hypophosphatemia. The phenotype is recognized by the skeletal features, which are related to hypophosphorylation of different FAM20C bone-target proteins. However, FAM20C has many targets, including brain proteins and the cerebrospinal fluid phosphoproteome. Individuals with RNS can have developmental delay, intellectual disability, seizures, and structural brain defects, but little is known about FAM20C brain-target-protein dysregulation or about a potential pathogenesis associated with neurologic features. In order to identify the potential FAM20C actions on the brain, an in silico analysis was conducted. Structural and functional defects reported in RNS were described; FAM20C targets and interactors were identified, including their brain expression. Gene ontology of molecular processes, function, and components was completed for these targets, as well as for potential involved signaling pathways and diseases. The BioGRID and Human Protein Atlas databases, the Gorilla tool, and the PANTHER and DisGeNET databases were used. Results show that genes with high expression in the brain are involved in cholesterol and lipoprotein processes, plus axo-dendritic transport and the neuron part. These results could highlight some proteins involved in the neurologic pathogenesis of RNS.
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Affiliation(s)
- Icela Palma-Lara
- Laboratorio de Morfología Celular y Molecular, Escuela Superior de Medicina, Instituto Politécnico Nacional, Ciudad de México 11340, Mexico
| | | | - Javier Pérez-Durán
- Instituto Nacional de Perinatología Isidro Espinosa de los Reyes, Ciudad de México 11000, Mexico
| | | | - José Bonilla-Delgado
- Unidad de Investigación, Hospital Regional de Ixtapaluca, Ixtapaluca 56530, Mexico
- Departamento de Biotecnología, Escuela de Ingeniería y Ciencias, Instituto Tecnológico de Monterrey, Toluca de Lerdo 50110, Mexico
| | - Damián Gómez-Archila
- Departamento de Oncología Quirúrgica, Hospital de Gineco-Obstetricia 3, Centro Médico Nacional "La Raza", Ciudad de México 02990, Mexico
| | | | - Manuel Nolasco-Quiroga
- Coordinación de Enseñanza e Investigación, Clínica Hospital Instituto de Seguridad y Servicios Sociales de los Trabajadores del Estado, Huauchinango 73177, Mexico
| | | | - Adolfo López-Ornelas
- División de Investigación, Hospital Juárez de México, Ciudad de México 11340, Mexico
| | - Juan Carlos Serrano-Bello
- Departamento de Patología Clínica y Experimental, Hospital Infantil de México Federico Gómez, Ciudad de México 06720, Mexico
| | | | - Carmen Palacios-Reyes
- División de Investigación, Hospital Juárez de México, Ciudad de México 11340, Mexico
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9
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Conti F, Pietrobon D. Astrocytic Glutamate Transporters and Migraine. Neurochem Res 2023; 48:1167-1179. [PMID: 36583835 DOI: 10.1007/s11064-022-03849-w] [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: 11/12/2022] [Revised: 12/07/2022] [Accepted: 12/17/2022] [Indexed: 12/31/2022]
Abstract
Glutamate levels and lifetime in the brain extracellular space are dinamically regulated by a family of Na+- and K+-dependent glutamate transporters, which thereby control numerous brain functions and play a role in numerous neurological and psychiatric diseases. Migraine is a neurological disorder characterized by recurrent attacks of typically throbbing and unilateral headache and by a global dysfunction in multisensory processing. Familial hemiplegic migraine type 2 (FHM2) is a rare monogenic form of migraine with aura caused by loss-of-function mutations in the α2 Na/K ATPase (α2NKA). In the adult brain, this pump is expressed almost exclusively in astrocytes where it is colocalized with glutamate transporters. Knockin mouse models of FHM2 (FHM2 mice) show a reduced density of glutamate transporters in perisynaptic astrocytic processes (mirroring the reduced expression of α2NKA) and a reduced rate of glutamate clearance at cortical synapses during neuronal activity and sensory stimulation. Here we review the migraine-relevant alterations produced by the astrocytic glutamate transport dysfunction in FHM2 mice and their underlying mechanisms, in particular regarding the enhanced brain susceptibility to cortical spreading depression (the phenomenon that underlies migraine aura and can also initiate the headache mechanisms) and the enhanced algesic response to a migraine trigger.
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Affiliation(s)
- Fiorenzo Conti
- Section of Neuroscience and Cell Biology, Department of Experimental and Clinical Medicine, Università Politecnica delle Marche, Ancona, Italy.
- Center for Neurobiology of Aging, IRCCS INRCA, Ancona, Italy.
| | - Daniela Pietrobon
- Department of Biomedical Sciences and Padova Neuroscience Center (PNC), University of Padova, 35131, Padua, Italy.
- CNR Institute of Neuroscience, 35131, Padua, Italy.
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10
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Schoknecht K, Hirrlinger J, Eilers J. Transient astrocytic accumulation of fluorescein during spreading depolarizations. Neurobiol Dis 2023; 178:106026. [PMID: 36731681 DOI: 10.1016/j.nbd.2023.106026] [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: 08/23/2022] [Revised: 01/16/2023] [Accepted: 01/29/2023] [Indexed: 02/01/2023] Open
Abstract
Spreading depolarizations (SDs) occur frequently in acute cerebral injuries. They are characterized by a breakdown of transmembrane ion gradients resulting in a reduced extracellular sodium ([Na+]o) and increased extracellular potassium concentration ([K+]o). Elevated [K+]o induces astrocytic swelling, another feature of SD; however, the solutes that drive astrocytic swelling remain incompletely understood. We incidentally found astrocytic accumulation of fluorescein (Fluo) - a low molecular weight anionic dye - during SDs induced by elevated [K+]o. Herein, we aimed to explore the properties of astrocytic Fluo accumulation during SDs, electrical stimulation, [K+]o and glutamate elevation and elucidate underlying mechanisms and its relation to swelling. Experiments were performed in acute neocortical slices from adult male C57Bl6 mice and transgenic mice expressing tdTomato in parvalbumin (PV)-positive neurons. We labeled astrocytes with sulforhodamine-101 (SR-101), measured Fluo kinetics using 2-photon laser scanning microscopy and recorded local field potentials (LFP) to detect SDs. Elevations of [K+]o lead to an increase of the astrocytic Fluo intensity in parallel with astrocytic swelling. Pharmacological inhibitors of sodium‑potassium ATPase (Na/K-ATPase), secondary-active transporters and channels were used to address the underlying mechanisms. Fluo accumulation as well as swelling were only prevented by inhibition of the sodium‑potassium ATPase. Application of glutamate or hypoosmolar solution induced astrocytic swelling independent of Fluo accumulation and glutamate opposed Fluo accumulation when co-administered with high [K+]o. Astrocytes accumulated Fluo and swelled during electrical stimulation and even more during SDs. Taken together, Fluo imaging can be used as a tool to visualize yet unidentified anion fluxes during [K+]o- but not glutamate- or hypoosmolarity induced astrocytic swelling. Fluo imaging may thereby help to elucidate mechanisms of astrocytic swelling and associated fluid movements between brain compartments during physiological and pathological conditions, e.g. SDs.
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Affiliation(s)
- Karl Schoknecht
- Carl-Ludwig-Institute of Physiology, Medical Faculty, Leipzig University, Leipzig, Germany.
| | - Johannes Hirrlinger
- Carl-Ludwig-Institute of Physiology, Medical Faculty, Leipzig University, Leipzig, Germany; Department of Neurogenetics, Max-Planck-Institute for Multidisciplinary Sciences, Göttingen, Germany
| | - Jens Eilers
- Carl-Ludwig-Institute of Physiology, Medical Faculty, Leipzig University, Leipzig, Germany
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11
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Rizk E, Madrid A, Koueik J, Sun D, Stewart K, Chen D, Luo S, Hong F, Papale LA, Hariharan N, Alisch RS, Iskandar BJ. Purified regenerating retinal neurons reveal regulatory role of DNA methylation-mediated Na+/K+-ATPase in murine axon regeneration. Commun Biol 2023; 6:120. [PMID: 36717618 PMCID: PMC9886953 DOI: 10.1038/s42003-023-04463-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2022] [Accepted: 01/11/2023] [Indexed: 01/31/2023] Open
Abstract
While embryonic mammalian central nervous system (CNS) axons readily grow and differentiate, only a minority of fully differentiated mature CNS neurons are able to regenerate injured axons, leading to stunted functional recovery after injury and disease. To delineate DNA methylation changes specifically associated with axon regeneration, we used a Fluorescent-Activated Cell Sorting (FACS)-based methodology in a rat optic nerve transection model to segregate the injured retinal ganglion cells (RGCs) into regenerating and non-regenerating cell populations. Whole-genome DNA methylation profiling of these purified neurons revealed genes and pathways linked to mammalian RGC regeneration. Moreover, whole-methylome sequencing of purified uninjured adult and embryonic RGCs identified embryonic molecular profiles reactivated after injury in mature neurons, and others that correlate specifically with embryonic or adult axon growth, but not both. The results highlight the contribution to both embryonic growth and adult axon regeneration of subunits encoding the Na+/K+-ATPase. In turn, both biochemical and genetic inhibition of the Na+/K+-ATPase pump significantly reduced RGC axon regeneration. These data provide critical molecular insights into mammalian CNS axon regeneration, pinpoint the Na+/K+-ATPase as a key regulator of regeneration of injured mature CNS axons, and suggest that successful regeneration requires, in part, reactivation of embryonic signals.
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Affiliation(s)
- Elias Rizk
- grid.14003.360000 0001 2167 3675Department of Neurological Surgery, University of Wisconsin-Madison School of Medicine and Public Health, Madison, WI 53792 USA ,grid.240473.60000 0004 0543 9901Department of Neurological Surgery, Penn State Milton S. Hershey Medical Center, Hershey, PA 17033 USA
| | - Andy Madrid
- grid.14003.360000 0001 2167 3675Department of Neurological Surgery, University of Wisconsin-Madison School of Medicine and Public Health, Madison, WI 53792 USA
| | - Joyce Koueik
- grid.14003.360000 0001 2167 3675Department of Neurological Surgery, University of Wisconsin-Madison School of Medicine and Public Health, Madison, WI 53792 USA
| | - Dandan Sun
- grid.21925.3d0000 0004 1936 9000Department of Neurology, University of Pittsburgh School of Medicine, Pittsburgh, PA 15213 USA
| | - Krista Stewart
- grid.14003.360000 0001 2167 3675Department of Neurological Surgery, University of Wisconsin-Madison School of Medicine and Public Health, Madison, WI 53792 USA
| | - David Chen
- grid.14003.360000 0001 2167 3675Department of Neurological Surgery, University of Wisconsin-Madison School of Medicine and Public Health, Madison, WI 53792 USA
| | - Susan Luo
- grid.14003.360000 0001 2167 3675Department of Neurological Surgery, University of Wisconsin-Madison School of Medicine and Public Health, Madison, WI 53792 USA
| | - Felissa Hong
- grid.14003.360000 0001 2167 3675Department of Neurological Surgery, University of Wisconsin-Madison School of Medicine and Public Health, Madison, WI 53792 USA
| | - Ligia A. Papale
- grid.14003.360000 0001 2167 3675Department of Neurological Surgery, University of Wisconsin-Madison School of Medicine and Public Health, Madison, WI 53792 USA
| | - Nithya Hariharan
- grid.14003.360000 0001 2167 3675Department of Neurological Surgery, University of Wisconsin-Madison School of Medicine and Public Health, Madison, WI 53792 USA
| | - Reid S. Alisch
- grid.14003.360000 0001 2167 3675Department of Neurological Surgery, University of Wisconsin-Madison School of Medicine and Public Health, Madison, WI 53792 USA
| | - Bermans J. Iskandar
- grid.14003.360000 0001 2167 3675Department of Neurological Surgery, University of Wisconsin-Madison School of Medicine and Public Health, Madison, WI 53792 USA
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12
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Bi W, Lei T, Cai S, Zhang X, Yang Y, Xiao Z, Wang L, Du H. Potential of astrocytes in targeting therapy for Alzheimer’s disease. Int Immunopharmacol 2022; 113:109368. [DOI: 10.1016/j.intimp.2022.109368] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2022] [Revised: 10/06/2022] [Accepted: 10/15/2022] [Indexed: 11/05/2022]
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13
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Mehrabian M, Wang X, Eid S, Yan BQ, Grinberg M, Siegner M, Sackmann C, Sulman M, Zhao W, Williams D, Schmitt-Ulms G. Cardiac glycoside-mediated turnover of Na, K-ATPases as a rational approach to reducing cell surface levels of the cellular prion protein. PLoS One 2022; 17:e0270915. [PMID: 35776750 PMCID: PMC9249225 DOI: 10.1371/journal.pone.0270915] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2021] [Accepted: 06/17/2022] [Indexed: 01/16/2023] Open
Abstract
It is widely anticipated that a reduction of brain levels of the cellular prion protein (PrPC) can prolong survival in a group of neurodegenerative diseases known as prion diseases. To date, efforts to decrease steady-state PrPC levels by targeting this protein directly with small molecule drug-like compounds have largely been unsuccessful. Recently, we reported Na,K-ATPases to reside in immediate proximity to PrPC in the brain, unlocking an opportunity for an indirect PrPC targeting approach that capitalizes on the availability of potent cardiac glycosides (CGs). Here, we report that exposure of human co-cultures of neurons and astrocytes to non-toxic nanomolar levels of CGs causes profound reductions in PrPC levels. The mechanism of action underpinning this outcome relies primarily on a subset of CGs engaging the ATP1A1 isoform, one of three α subunits of Na,K-ATPases expressed in brain cells. Upon CG docking to ATP1A1, the ligand receptor complex, and PrPC along with it, is internalized by the cell. Subsequently, PrPC is channeled to the lysosomal compartment where it is digested in a manner that can be rescued by silencing the cysteine protease cathepsin B. These data signify that the repurposing of CGs may be beneficial for the treatment of prion disorders.
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Affiliation(s)
- Mohadeseh Mehrabian
- Tanz Centre for Research in Neurodegenerative Diseases, University of Toronto, Krembil Discovery Centre, Toronto, Ontario, Canada
- Department of Laboratory Medicine & Pathobiology, University of Toronto, Toronto, Ontario, Canada
| | - Xinzhu Wang
- Tanz Centre for Research in Neurodegenerative Diseases, University of Toronto, Krembil Discovery Centre, Toronto, Ontario, Canada
- Department of Laboratory Medicine & Pathobiology, University of Toronto, Toronto, Ontario, Canada
| | - Shehab Eid
- Tanz Centre for Research in Neurodegenerative Diseases, University of Toronto, Krembil Discovery Centre, Toronto, Ontario, Canada
- Department of Laboratory Medicine & Pathobiology, University of Toronto, Toronto, Ontario, Canada
| | - Bei Qi Yan
- Tanz Centre for Research in Neurodegenerative Diseases, University of Toronto, Krembil Discovery Centre, Toronto, Ontario, Canada
- Department of Laboratory Medicine & Pathobiology, University of Toronto, Toronto, Ontario, Canada
| | - Mark Grinberg
- Tanz Centre for Research in Neurodegenerative Diseases, University of Toronto, Krembil Discovery Centre, Toronto, Ontario, Canada
| | - Murdock Siegner
- Tanz Centre for Research in Neurodegenerative Diseases, University of Toronto, Krembil Discovery Centre, Toronto, Ontario, Canada
- Department of Laboratory Medicine & Pathobiology, University of Toronto, Toronto, Ontario, Canada
| | - Christopher Sackmann
- Tanz Centre for Research in Neurodegenerative Diseases, University of Toronto, Krembil Discovery Centre, Toronto, Ontario, Canada
| | - Muhammad Sulman
- Tanz Centre for Research in Neurodegenerative Diseases, University of Toronto, Krembil Discovery Centre, Toronto, Ontario, Canada
| | - Wenda Zhao
- Tanz Centre for Research in Neurodegenerative Diseases, University of Toronto, Krembil Discovery Centre, Toronto, Ontario, Canada
- Department of Laboratory Medicine & Pathobiology, University of Toronto, Toronto, Ontario, Canada
| | - Declan Williams
- Tanz Centre for Research in Neurodegenerative Diseases, University of Toronto, Krembil Discovery Centre, Toronto, Ontario, Canada
| | - Gerold Schmitt-Ulms
- Tanz Centre for Research in Neurodegenerative Diseases, University of Toronto, Krembil Discovery Centre, Toronto, Ontario, Canada
- Department of Laboratory Medicine & Pathobiology, University of Toronto, Toronto, Ontario, Canada
- * E-mail:
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14
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Fedosova NU, Habeck M, Nissen P. Structure and Function of Na,K-ATPase-The Sodium-Potassium Pump. Compr Physiol 2021; 12:2659-2679. [PMID: 34964112 DOI: 10.1002/cphy.c200018] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Na,K-ATPase is an ubiquitous enzyme actively transporting Na-ions out of the cell in exchange for K-ions, thereby maintaining their concentration gradients across the cell membrane. Since its discovery more than six decades ago the Na-pump has been studied extensively and its vital physiological role in essentially every cell has been established. This article aims at providing an overview of well-established biochemical properties with a focus on Na,K-ATPase isoforms, its transport mechanism and principle conformations, inhibitors, and insights gained from crystal structures. © 2021 American Physiological Society. Compr Physiol 11:1-21, 2021.
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Affiliation(s)
| | - Michael Habeck
- Department of Molecular Biology and Genetics, Danish Research Institute of Translational Neuroscience - DANDRITE, Nordic EMBL Partnership for Molecular Medicine, Aarhus University, Aarhus, Denmark
| | - Poul Nissen
- Department of Molecular Biology and Genetics, Danish Research Institute of Translational Neuroscience - DANDRITE, Nordic EMBL Partnership for Molecular Medicine, Aarhus University, Aarhus, Denmark
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15
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Contreras SA, Schleimer JH, Gulledge AT, Schreiber S. Activity-mediated accumulation of potassium induces a switch in firing pattern and neuronal excitability type. PLoS Comput Biol 2021; 17:e1008510. [PMID: 34043638 PMCID: PMC8205125 DOI: 10.1371/journal.pcbi.1008510] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2020] [Revised: 06/15/2021] [Accepted: 04/16/2021] [Indexed: 01/30/2023] Open
Abstract
During normal neuronal activity, ionic concentration gradients across a neuron’s membrane are often assumed to be stable. Prolonged spiking activity, however, can reduce transmembrane gradients and affect voltage dynamics. Based on mathematical modeling, we investigated the impact of neuronal activity on ionic concentrations and, consequently, the dynamics of action potential generation. We find that intense spiking activity on the order of a second suffices to induce changes in ionic reversal potentials and to consistently induce a switch from a regular to an intermittent firing mode. This transition is caused by a qualitative alteration in the system’s voltage dynamics, mathematically corresponding to a co-dimension-two bifurcation from a saddle-node on invariant cycle (SNIC) to a homoclinic orbit bifurcation (HOM). Our electrophysiological recordings in mouse cortical pyramidal neurons confirm the changes in action potential dynamics predicted by the models: (i) activity-dependent increases in intracellular sodium concentration directly reduce action potential amplitudes, an effect typically attributed solely to sodium channel inactivation; (ii) extracellular potassium accumulation switches action potential generation from tonic firing to intermittently interrupted output. Thus, individual neurons may respond very differently to the same input stimuli, depending on their recent patterns of activity and/or the current brain-state. Ionic concentrations in the brain are not constant. We show that during intense neuronal activity, they can change on the order of seconds and even switch neuronal spiking patterns under identical stimulation from a regular firing mode to an intermittently interrupted one. Triggered by an accumulation of extracellular potassium, such a transition is caused by a specific, qualitative change in of the neuronal voltage dynamics—a so-called bifurcation—which affects crucial features of action-potential generation and bears consequences for how information is encoded and how neurons behave together in the network. Also, changes in intracellular sodium can induce measurable effects, like a reduction of spike amplitude that occurs independently of the fast amplitude effects attributed to sodium channel inactivation. Taken together, our results demonstrate that a neuron can respond very differently to the same stimulus, depending on its previous activity or the current brain state. This finding may be particularly relevant when other regulatory mechanisms of ionic homeostasis are challenged, for example, during pathological states of glial impairment or oxygen deprivation. Finally, categorization of cortical neurons as intrinsically bursting or regular spiking may be biased by the ionic concentrations at the time of the observation, highlighting the non-static nature of neuronal dynamics.
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Affiliation(s)
- Susana Andrea Contreras
- Institute for Theoretical Biology, Humboldt-University of Berlin, Berlin, Germany
- Bernstein Center for Computational Neuroscience Berlin, Berlin, Germany
| | - Jan-Hendrik Schleimer
- Institute for Theoretical Biology, Humboldt-University of Berlin, Berlin, Germany
- Bernstein Center for Computational Neuroscience Berlin, Berlin, Germany
| | - Allan T. Gulledge
- Molecular and Systems Biology, Geisel School of Medicine at Dartmouth College, Hanover, New Hampshire, United States of America
| | - Susanne Schreiber
- Institute for Theoretical Biology, Humboldt-University of Berlin, Berlin, Germany
- Bernstein Center for Computational Neuroscience Berlin, Berlin, Germany
- * E-mail:
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16
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Podvin S, Jones A, Liu Q, Aulston B, Mosier C, Ames J, Winston C, Lietz CB, Jiang Z, O’Donoghue AJ, Ikezu T, Rissman RA, Yuan SH, Hook V. Mutant Presenilin 1 Dysregulates Exosomal Proteome Cargo Produced by Human-Induced Pluripotent Stem Cell Neurons. ACS OMEGA 2021; 6:13033-13056. [PMID: 34056454 PMCID: PMC8158845 DOI: 10.1021/acsomega.1c00660] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/04/2021] [Accepted: 04/16/2021] [Indexed: 05/28/2023]
Abstract
The accumulation and propagation of hyperphosphorylated tau (p-Tau) is a neuropathological hallmark occurring with neurodegeneration of Alzheimer's disease (AD). Extracellular vesicles, exosomes, have been shown to initiate tau propagation in the brain. Notably, exosomes from human-induced pluripotent stem cell (iPSC) neurons expressing the AD familial A246E mutant form of presenilin 1 (mPS1) are capable of inducing tau deposits in the mouse brain after in vivo injection. To gain insights into the exosome proteome cargo that participates in propagating tau pathology, this study conducted proteomic analysis of exosomes produced by human iPSC neurons expressing A246E mPS1. Significantly, mPS1 altered the profile of exosome cargo proteins to result in (1) proteins present only in mPS1 exosomes and not in controls, (2) the absence of proteins in the mPS1 exosomes which were present only in controls, and (3) shared proteins which were upregulated or downregulated in the mPS1 exosomes compared to controls. These results show that mPS1 dysregulates the proteome cargo of exosomes to result in the acquisition of proteins involved in the extracellular matrix and protease functions, deletion of proteins involved in RNA and protein translation systems along with proteasome and related functions, combined with the upregulation and downregulation of shared proteins, including the upregulation of amyloid precursor protein. Notably, mPS1 neuron-derived exosomes displayed altered profiles of protein phosphatases and kinases involved in regulating the status of p-tau. The dysregulation of exosome cargo proteins by mPS1 may be associated with the ability of mPS1 neuron-derived exosomes to propagate tau pathology.
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Affiliation(s)
- Sonia Podvin
- Skaggs
School of Pharmacy and Pharmaceutical Sciences, University of California San Diego,
La Jolla, San Diego 92093, California, United States
| | - Alexander Jones
- Biomedical
Sciences Graduate Program, University of
California, San Diego, La Jolla, San Diego 92093, California, United States
| | - Qing Liu
- Department
of Neurosciences, School of Medicine, University
of California, San Diego, La Jolla, San Diego 92093, California, United States
| | - Brent Aulston
- Department
of Neurosciences, School of Medicine, University
of California, San Diego, La Jolla, San Diego 92093, California, United States
| | - Charles Mosier
- Skaggs
School of Pharmacy and Pharmaceutical Sciences, University of California San Diego,
La Jolla, San Diego 92093, California, United States
| | - Janneca Ames
- Skaggs
School of Pharmacy and Pharmaceutical Sciences, University of California San Diego,
La Jolla, San Diego 92093, California, United States
| | - Charisse Winston
- Department
of Neurosciences, School of Medicine, University
of California, San Diego, La Jolla, San Diego 92093, California, United States
| | - Christopher B. Lietz
- Skaggs
School of Pharmacy and Pharmaceutical Sciences, University of California San Diego,
La Jolla, San Diego 92093, California, United States
| | - Zhenze Jiang
- Skaggs
School of Pharmacy and Pharmaceutical Sciences, University of California San Diego,
La Jolla, San Diego 92093, California, United States
| | - Anthony J. O’Donoghue
- Skaggs
School of Pharmacy and Pharmaceutical Sciences, University of California San Diego,
La Jolla, San Diego 92093, California, United States
| | - Tsuneya Ikezu
- Department
of Pharmacology and Experimental Therapeutics, Department of Neurology,
Alzheimer’s Disease Research Center, Boston University, School of Medicine, Boston 02118, Massachusetts, United States
| | - Robert A. Rissman
- Department
of Neurosciences, School of Medicine, University
of California, San Diego, La Jolla, San Diego 92093, California, United States
- Veterans
Affairs San Diego Healthcare System,
La Jolla, San Diego 92161, California, United States
| | - Shauna H. Yuan
- Department
of Neurosciences, School of Medicine, University
of California, San Diego, La Jolla, San Diego 92093, California, United States
| | - Vivian Hook
- Skaggs
School of Pharmacy and Pharmaceutical Sciences, University of California San Diego,
La Jolla, San Diego 92093, California, United States
- Biomedical
Sciences Graduate Program, University of
California, San Diego, La Jolla, San Diego 92093, California, United States
- Department
of Neurosciences, School of Medicine, University
of California, San Diego, La Jolla, San Diego 92093, California, United States
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17
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Vetro A, Nielsen HN, Holm R, Hevner RF, Parrini E, Powis Z, Møller RS, Bellan C, Simonati A, Lesca G, Helbig KL, Palmer EE, Mei D, Ballardini E, Van Haeringen A, Syrbe S, Leuzzi V, Cioni G, Curry CJ, Costain G, Santucci M, Chong K, Mancini GMS, Clayton-Smith J, Bigoni S, Scheffer IE, Dobyns WB, Vilsen B, Guerrini R. ATP1A2- and ATP1A3-associated early profound epileptic encephalopathy and polymicrogyria. Brain 2021; 144:1435-1450. [PMID: 33880529 DOI: 10.1093/brain/awab052] [Citation(s) in RCA: 31] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2020] [Revised: 12/08/2020] [Accepted: 12/09/2020] [Indexed: 01/20/2023] Open
Abstract
Constitutional heterozygous mutations of ATP1A2 and ATP1A3, encoding for two distinct isoforms of the Na+/K+-ATPase (NKA) alpha-subunit, have been associated with familial hemiplegic migraine (ATP1A2), alternating hemiplegia of childhood (ATP1A2/A3), rapid-onset dystonia-parkinsonism, cerebellar ataxia-areflexia-progressive optic atrophy, and relapsing encephalopathy with cerebellar ataxia (all ATP1A3). A few reports have described single individuals with heterozygous mutations of ATP1A2/A3 associated with severe childhood epilepsies. Early lethal hydrops fetalis, arthrogryposis, microcephaly, and polymicrogyria have been associated with homozygous truncating mutations in ATP1A2. We investigated the genetic causes of developmental and epileptic encephalopathies variably associated with malformations of cortical development in a large cohort and identified 22 patients with de novo or inherited heterozygous ATP1A2/A3 mutations. We characterized clinical, neuroimaging and neuropathological findings, performed in silico and in vitro assays of the mutations' effects on the NKA-pump function, and studied genotype-phenotype correlations. Twenty-two patients harboured 19 distinct heterozygous mutations of ATP1A2 (six patients, five mutations) and ATP1A3 (16 patients, 14 mutations, including a mosaic individual). Polymicrogyria occurred in 10 (45%) patients, showing a mainly bilateral perisylvian pattern. Most patients manifested early, often neonatal, onset seizures with a multifocal or migrating pattern. A distinctive, 'profound' phenotype, featuring polymicrogyria or progressive brain atrophy and epilepsy, resulted in early lethality in seven patients (32%). In silico evaluation predicted all mutations to be detrimental. We tested 14 mutations in transfected COS-1 cells and demonstrated impaired NKA-pump activity, consistent with severe loss of function. Genotype-phenotype analysis suggested a link between the most severe phenotypes and lack of COS-1 cell survival, and also revealed a wide continuum of severity distributed across mutations that variably impair NKA-pump activity. We performed neuropathological analysis of the whole brain in two individuals with polymicrogyria respectively related to a heterozygous ATP1A3 mutation and a homozygous ATP1A2 mutation and found close similarities with findings suggesting a mainly neural pathogenesis, compounded by vascular and leptomeningeal abnormalities. Combining our report with other studies, we estimate that ∼5% of mutations in ATP1A2 and 12% in ATP1A3 can be associated with the severe and novel phenotypes that we describe here. Notably, a few of these mutations were associated with more than one phenotype. These findings assign novel, 'profound' and early lethal phenotypes of developmental and epileptic encephalopathies and polymicrogyria to the phenotypic spectrum associated with heterozygous ATP1A2/A3 mutations and indicate that severely impaired NKA pump function can disrupt brain morphogenesis.
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Affiliation(s)
- Annalisa Vetro
- Pediatric Neurology, Neurogenetics and Neurobiology Unit and Laboratories, Meyer Children's Hospital, University of Florence, Florence, Italy
| | - Hang N Nielsen
- Department of Biomedicine, Aarhus University, DK-8000, Aarhus C, Denmark
| | - Rikke Holm
- Department of Biomedicine, Aarhus University, DK-8000, Aarhus C, Denmark
| | - Robert F Hevner
- Department of Pathology, University of California San Diego, San Diego, CA, USA
| | - Elena Parrini
- Pediatric Neurology, Neurogenetics and Neurobiology Unit and Laboratories, Meyer Children's Hospital, University of Florence, Florence, Italy
| | - Zoe Powis
- Ambry Genetics, Aliso Viejo, CA, USA
| | - Rikke S Møller
- Department of Epilepsy Genetics and Personalized Medicine Danish Epilepsy Centre, Filadelfia, Denmark.,Department of Regional Health Services, University of Southern Denmark, Odense, Denmark
| | - Cristina Bellan
- Department of Neonatal Intensive Care Unit, Bolognini Hospital, ASST-Bergamo Est, Seriate, Italy
| | - Alessandro Simonati
- Neurology (Child Neurology and Neuropathology), Department of Neuroscience, Biomedicine and Movement, University of Verona, Verona, Italy
| | - Gaétan Lesca
- Department of Medical Genetics, Member of the ERN EpiCARE, University Hospital of Lyon, Lyon, France
| | - Katherine L Helbig
- Division of Neurology, Children's Hospital of Philadelphia, Philadelphia, PA, USA
| | - Elizabeth E Palmer
- Centre for Clinical Genetics, Sydney Children's Hospital, Randwick, NSW, Australia.,School of Women's and Children's Health, University of New South Wales, Randwick, NSW, Australia
| | - Davide Mei
- Pediatric Neurology, Neurogenetics and Neurobiology Unit and Laboratories, Meyer Children's Hospital, University of Florence, Florence, Italy
| | - Elisa Ballardini
- Neonatal Intensive Care Unit, Pediatric Section, Department of Medical Sciences, Ferrara University, Ferrara, Italy
| | - Arie Van Haeringen
- Department of Clinical Genetics, Leiden University Medical Center, Leiden, The Netherlands
| | - Steffen Syrbe
- Division of Pediatric Epileptology, Centre for Paediatrics and Adolescent Medicine, University Hospital Heidelberg, Heidelberg, Germany
| | - Vincenzo Leuzzi
- Department of Human Neuroscience, Unit of Child Neurology and Psychiatry, Sapienza University, Rome, Italy
| | - Giovanni Cioni
- Department of Developmental Neuroscience, IRCCS Fondazione Stella Maris, Pisa, Italy
| | - Cynthia J Curry
- Genetic Medicine, Department of Pediatrics, University of California, San Francisco/Fresno, CA, USA
| | - Gregory Costain
- Division of Clinical and Metabolic Genetics, Department of Pediatrics, The Hospital for Sick Children, Toronto, Ontario, Canada
| | - Margherita Santucci
- Child Neuropsychiatry Unit, IRCCS, Institute of Neurological Sciences, Bellaria Hospital, Bologna, Italy.,DIBINEM, University of Bologna, Bologna, Italy
| | - Karen Chong
- The Prenatal Diagnosis and Medical Genetics Program, Department of Obstetrics and Gynecology, Mount Sinai Hospital, University of Toronto, Toronto, ON, Canada
| | - Grazia M S Mancini
- Department of Clinical Genetics, Erasmus MC University Medical Center, Rotterdam, The Netherlands
| | - Jill Clayton-Smith
- Manchester Centre for Genomic Medicine, University of Manchester, St Mary's Hospital, Manchester, UK
| | - Stefania Bigoni
- Medical Genetics Unit, Department of Mother and Child, Ferrara University Hospital, Ferrara, Italy
| | - Ingrid E Scheffer
- University of Melbourne, Austin Health and Royal Children's Hospital, Florey and Murdoch Institutes, Melbourne, Australia
| | - William B Dobyns
- Department of Pediatrics (Genetics), University of Minnesota, Minneapolis, MN, USA
| | - Bente Vilsen
- Department of Biomedicine, Aarhus University, DK-8000, Aarhus C, Denmark
| | - Renzo Guerrini
- Pediatric Neurology, Neurogenetics and Neurobiology Unit and Laboratories, Meyer Children's Hospital, University of Florence, Florence, Italy
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18
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Decreased content of ascorbic acid (vitamin C) in the brain of knockout mouse models of Na+,K+-ATPase-related neurologic disorders. PLoS One 2021; 16:e0246678. [PMID: 33544780 PMCID: PMC7864419 DOI: 10.1371/journal.pone.0246678] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2020] [Accepted: 01/23/2021] [Indexed: 12/21/2022] Open
Abstract
Na+,K+-ATPase is a crucial protein responsible for maintaining the electrochemical gradients across the cell membrane. The Na+,K+-ATPase is comprised of catalytic α, β, and γ subunits. In adult brains, the α3 subunit, encoded by ATP1A3, is predominantly expressed in neurons, whereas the α2 subunit, encoded by ATP1A2, is expressed in glial cells. In foetal brains, the α2 is expressed in neurons as well. Mutations in α subunits cause a variety of neurologic disorders. Notably, the onset of symptoms in ATP1A2- and ATP1A3-related neurologic disorders is usually triggered by physiological or psychological stressors. To gain insight into the distinct roles of the α2 and α3 subunits in the developing foetal brain, whose developmental dysfunction may be a predisposing factor of neurologic disorders, we compared the phenotypes of mouse foetuses with double homozygous knockout of Atp1a2 and Atp1a3 (α2α3-dKO) to those with single knockout. The brain haemorrhage phenotype of α2α3-dKO was similar to that of homozygous knockout of the gene encoding ascorbic acid (ASC or vitamin C) transporter, SVCT2. The α2α3-dKO brain showed significantly decreased level of ASC compared with the wild-type (WT) and single knockout. We found that the ASC content in the basal ganglia and cerebellum was significantly lower in the adult Atp1a3 heterozygous knockout mouse (α3-HT) than in the WT. Interestingly, we observed a significant decrease in the ASC level in the basal ganglia and cerebellum of α3-HT in the peripartum period, during which mice are under physiological stress. These observations indicate that the α2 and α3 subunits independently contribute to the ASC level in the foetal brain and that the α3 subunit contributes to ASC transport in the adult basal ganglia and cerebellum. We propose that decreases in ASC levels may affect neural network development and are linked to the pathophysiology of ATP1A2- and ATP1A3-related neurologic disorders.
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19
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Margineanu MB, Sherwin E, Golubeva A, Peterson V, Hoban A, Fiumelli H, Rea K, Cryan JF, Magistretti PJ. Gut microbiota modulates expression of genes involved in the astrocyte-neuron lactate shuttle in the hippocampus. Eur Neuropsychopharmacol 2020; 41:152-159. [PMID: 33191074 DOI: 10.1016/j.euroneuro.2020.11.006] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/17/2019] [Revised: 10/06/2020] [Accepted: 11/02/2020] [Indexed: 12/20/2022]
Abstract
The gut microbiota modulates brain physiology, development, and behavior and has been implicated as a key regulator in several central nervous system disorders. Its effect on the metabolic coupling between neurons and astrocytes has not been studied to date, even though this is an important component of brain energy metabolism and physiology and it is perturbed in neurodegenerative and cognitive disorders. In this study, we have investigated the mRNA expression of 6 genes encoding proteins implicated in the astrocyte-neuron lactate shuttle (Atp1a2, Ldha, Ldhb, Mct1, Gys1, Pfkfb3), in relation to different gut microbiota manipulations, in the mouse brain hippocampus, a region with critical functions in cognition and behavior. We have discovered that Atp1a2 and Pfkfb3, encoding the ATPase, Na+/K+ transporting, alpha 2 sub-unit, respectively and 6-phosphofructo-2-kinase/fructose-2,6-biphosphatase 3, two genes predominantly expressed in astrocytes, were upregulated in the hippocampus after microbial colonization of germ-free mice for 24 h, compared with conventionally raised mice. Pfkfb3 was also upregulated in germ-free mice compared with conventionally raised mice, while an increase in Atp1a2 expression in germ-free mice was confirmed only at the protein level by Western blot. In a separate cohort of mice, Atp1a2 and Pfkfb3 mRNA expression was upregulated in the hippocampus following 6-week dietary supplementation with prebiotics (fructo- and galacto-oligosaccharides) in an animal model of chronic psychosocial stress. To our knowledge, these findings are the first to report an influence of the gut microbiota and prebiotics on mRNA expression of genes implicated in the metabolic coupling between neurons and astrocytes.
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Affiliation(s)
- Michael B Margineanu
- Laboratory for Cellular Imaging and Energetics, Biological and Environmental Sciences and Engineering Division (BESE), King Abdullah University of Science and Technology (KAUST), Thuwal 23955-6900, Saudi Arabia; OncoGen Research Centre, "Pius Brinzeu" County Emergency Hospital, Timisoara, Romania; Department of Functional Sciences, "Victor Babeș" University of Medicine and Pharmacy, Timisoara, Romania
| | - Eoin Sherwin
- APC Microbiome Ireland, University College Cork, Cork, Ireland
| | - Anna Golubeva
- APC Microbiome Ireland, University College Cork, Cork, Ireland; Department of Anatomy and Neuroscience, University College Cork, Cork, Ireland
| | - Veronica Peterson
- APC Microbiome Ireland, University College Cork, Cork, Ireland; Teagasc Food Research Centre, Moorepark, Fermoy, Cork, Ireland
| | - Alan Hoban
- APC Microbiome Ireland, University College Cork, Cork, Ireland; Department of Anatomy and Neuroscience, University College Cork, Cork, Ireland
| | - Hubert Fiumelli
- Laboratory for Cellular Imaging and Energetics, Biological and Environmental Sciences and Engineering Division (BESE), King Abdullah University of Science and Technology (KAUST), Thuwal 23955-6900, Saudi Arabia
| | - Kieran Rea
- APC Microbiome Ireland, University College Cork, Cork, Ireland
| | - John F Cryan
- APC Microbiome Ireland, University College Cork, Cork, Ireland; Department of Anatomy and Neuroscience, University College Cork, Cork, Ireland.
| | - Pierre J Magistretti
- Laboratory for Cellular Imaging and Energetics, Biological and Environmental Sciences and Engineering Division (BESE), King Abdullah University of Science and Technology (KAUST), Thuwal 23955-6900, Saudi Arabia.
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20
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Petrushanko IY, Mitkevich VA, Makarov AA. Molecular Mechanisms of the Redox Regulation of the Na,K-ATPase. Biophysics (Nagoya-shi) 2020. [DOI: 10.1134/s0006350920050139] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
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21
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Melone M, Ciriachi C, Pietrobon D, Conti F. Heterogeneity of Astrocytic and Neuronal GLT-1 at Cortical Excitatory Synapses, as Revealed by its Colocalization With Na+/K+-ATPase α Isoforms. Cereb Cortex 2020; 29:3331-3350. [PMID: 30260367 DOI: 10.1093/cercor/bhy203] [Citation(s) in RCA: 31] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2018] [Revised: 08/01/2018] [Accepted: 08/03/2018] [Indexed: 12/29/2022] Open
Abstract
GLT-1, the major glutamate transporter, is expressed at perisynaptic astrocytic processes (PAP) and axon terminals (AxT). GLT-1 is coupled to Na+/K+-ATPase (NKA) α1-3 isoforms, whose subcellular distribution and spatial organization in relationship to GLT-1 are largely unknown. Using several microscopy techniques, we showed that at excitatory synapses α1 and α3 are exclusively neuronal (mainly in dendrites and in some AxT), while α2 is predominantly astrocytic. GLT-1 displayed a differential colocalization with α1-3. GLT-1/α2 and GLT-1/α3 colocalization was higher in GLT-1 positive puncta partially (for GLT-1/α2) or almost totally (for GLT-1/α3) overlapping with VGLUT1 positive terminals than in nonoverlapping ones. GLT-1 colocalized with α2 at PAP, and with α1 and α3 at AxT. GLT-1 and α2 gold particles were ∼1.5-2 times closer than GLT-1/α1 and GLT-1/α3 particles. GLT-1/α2 complexes (edge to edge interdistance of gold particles ≤50 nm) concentrated at the perisynaptic region of PAP membranes, whereas neuronal GLT-1/α1 and GLT-1/α3 complexes were fewer and more uniformly distributed in AxT. These data unveil different composition of GLT-1 and α subunits complexes in the glial and neuronal domains of excitatory synapses. The spatial organization of GLT-1/α1-3 complexes suggests that GLT-1/NKA interaction is more efficient in astrocytes than in neurons, further supporting the dominant role of astrocytic GLT-1 in glutamate homeostasis.
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Affiliation(s)
- Marcello Melone
- Section of Neuroscience and Cell Biology, Department of Experimental and Clinical Medicine, Università Politecnica delle Marche, Ancona, Italy.,Center for Neurobiology of Aging, IRCCS INRCA, Ancona, Italy
| | - Chiara Ciriachi
- Section of Neuroscience and Cell Biology, Department of Experimental and Clinical Medicine, Università Politecnica delle Marche, Ancona, Italy
| | - Daniela Pietrobon
- Department of Biomedical Sciences, University of Padova, and CNR Institute of Neuroscience, Padova, Italy
| | - Fiorenzo Conti
- Section of Neuroscience and Cell Biology, Department of Experimental and Clinical Medicine, Università Politecnica delle Marche, Ancona, Italy.,Center for Neurobiology of Aging, IRCCS INRCA, Ancona, Italy.,Foundation for Molecular Medicine, Università Politecnica delle Marche, Ancona, Italy
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22
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Chatron N, Cabet S, Alix E, Buenerd A, Cox P, Guibaud L, Labalme A, Marks P, Osio D, Putoux A, Sanlaville D, Lesca G, Vasiljevic A. A novel lethal recognizable polymicrogyric syndrome caused by ATP1A2 homozygous truncating variants. Brain 2020; 142:3367-3374. [PMID: 31608932 DOI: 10.1093/brain/awz272] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2018] [Revised: 06/20/2019] [Accepted: 07/11/2019] [Indexed: 11/14/2022] Open
Abstract
Polymicrogyria is a heterogeneous malformation of cortical development microscopically defined by an excessive folding of the cortical mantle resulting in small gyri with a fused surface. Polymicrogyria is responsible for a wide range of neurological symptoms (e.g. epilepsy, intellectual disability, motor dysfunction). Most cases have a supposed environmental clastic vascular or infectious origin but progress in genomics has revealed new monogenic entities. We report four cases from two independent families sharing a common recognizable lethal syndromic polymicrogyria of autosomal recessive inheritance. Beyond diffuse polymicrogyria detected prenatally, pathological examination revealed a common pattern associating meningeal arterial calcifications, necrotic and calcified areas in basal ganglia, dentato-olivary dysplasia and severe hypoplasia/agenesis of the pyramidal tracts. In all affected cases, exome sequencing showed a pathogenic homozygous nonsense ATP1A2 variant. This resulted in absence of immunodetectable ATP1A2 protein in two brains analysed. ATP1A2 encodes the alpha-2 isoform of the Na+/K+-ATPase, which is highly expressed in brain tissues and has previously been related to familial hemiplegic migraine (MIM#602481) and alternating hemiplegia of childhood (MIM#104290). Through the description of this genetic entity, we emphasize the possibility of dual mode of transmission for disease-causing genes and provide the key neuropathological features that should prompt geneticists to test for mutations in the ATP1A2 gene.
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Affiliation(s)
- Nicolas Chatron
- Genetics Department, Hospices Civils de Lyon, Lyon, France.,GENDEV Team, CRNL, INSERM U1028, CNRS UMR 5292, UCBL1, Lyon, France
| | - Sara Cabet
- Imagerie pédiatrique et fœtale, UCBL Lyon I, Hôpital Femme Mère Enfant, Lyon-Bron, France
| | - Eudeline Alix
- Genetics Department, Hospices Civils de Lyon, Lyon, France
| | - Annie Buenerd
- Institut de Pathologie Multi-sites des HCL/Centre de Pathologie et Fœtopathologie Est, Lyon, France
| | - Phillip Cox
- Department of Histopathology, Birmingham Women's and Children's Hospital NHSFT, Birmingham, UK
| | - Laurent Guibaud
- Imagerie pédiatrique et fœtale, UCBL Lyon I, Hôpital Femme Mère Enfant, Lyon-Bron, France
| | - Audrey Labalme
- Genetics Department, Hospices Civils de Lyon, Lyon, France
| | - Peter Marks
- West Midlands Regional Genetics Service, Birmingham Women's and Children's Hospital NHSFT, Birmingham, UK
| | - Deborah Osio
- West Midlands Regional Genetics Service, Birmingham Women's and Children's Hospital NHSFT, Birmingham, UK
| | - Audrey Putoux
- Genetics Department, Hospices Civils de Lyon, Lyon, France.,GENDEV Team, CRNL, INSERM U1028, CNRS UMR 5292, UCBL1, Lyon, France
| | - Damien Sanlaville
- Genetics Department, Hospices Civils de Lyon, Lyon, France.,GENDEV Team, CRNL, INSERM U1028, CNRS UMR 5292, UCBL1, Lyon, France
| | - Gaetan Lesca
- Genetics Department, Hospices Civils de Lyon, Lyon, France.,GENDEV Team, CRNL, INSERM U1028, CNRS UMR 5292, UCBL1, Lyon, France
| | - Alexandre Vasiljevic
- Institut de Pathologie Multi-sites des HCL/Centre de Pathologie et Fœtopathologie Est, Lyon, France
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23
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PINK1/Parkin Mediated Mitophagy, Ca 2+ Signalling, and ER-Mitochondria Contacts in Parkinson's Disease. Int J Mol Sci 2020; 21:ijms21051772. [PMID: 32150829 PMCID: PMC7084677 DOI: 10.3390/ijms21051772] [Citation(s) in RCA: 109] [Impact Index Per Article: 27.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2020] [Revised: 03/02/2020] [Accepted: 03/03/2020] [Indexed: 12/19/2022] Open
Abstract
Endoplasmic reticulum (ER)–mitochondria contact sites are critical structures for cellular function. They are implicated in a plethora of cellular processes, including Ca2+ signalling and mitophagy, the selective degradation of damaged mitochondria. Phosphatase and tensin homolog (PTEN)-induced kinase (PINK) and Parkin proteins, whose mutations are associated with familial forms of Parkinson’s disease, are two of the best characterized mitophagy players. They accumulate at ER–mitochondria contact sites and modulate organelles crosstalk. Alterations in ER–mitochondria tethering are a common hallmark of many neurodegenerative diseases including Parkinson’s disease. Here, we summarize the current knowledge on the involvement of PINK1 and Parkin at the ER–mitochondria contact sites and their role in the modulation of Ca2+ signalling and mitophagy.
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24
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Reiffurth C, Alam M, Zahedi-Khorasani M, Major S, Dreier JP. Na +/K +-ATPase α isoform deficiency results in distinct spreading depolarization phenotypes. J Cereb Blood Flow Metab 2020; 40:622-638. [PMID: 30819023 PMCID: PMC7025397 DOI: 10.1177/0271678x19833757] [Citation(s) in RCA: 24] [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] [Indexed: 12/11/2022]
Abstract
Compromised Na+/K+-ATPase function is associated with the occurrence of spreading depolarization (SD). Mutations in ATP1A2, the gene encoding the α2 isoform of the Na+/K+-ATPase, were identified in patients with familial hemiplegic migraine type 2 (FHM2), a Mendelian model disease for SD. This suggests a distinct role for the α2 isoform in modulating SD susceptibility and raises questions about underlying mechanisms including the roles of other Na+/K+-ATPase α isoforms. Here, we investigated the effects of genetic ablation and pharmacological inhibition of α1, α2, and α3 on SD using heterozygous knock-out mice. We found that only α2 heterozygous mice displayed higher SD susceptibility when challenged with prolonged extracellular high potassium concentration ([K+]o), a pronounced post SD oligemia and higher SD speed in-vivo. By contrast, under physiological [K+]o, α2 heterozygous mice showed similar SD susceptibility compared to wild-type littermates. Deficiency of α3 resulted in increased resistance against electrically induced SD in-vivo, whereas α1 deficiency did not affect SD. The results support important roles of the α2 isoform in SD. Moreover, they suggest that specific experimental conditions can be necessary to reveal an inherent SD phenotype by driving a (meta-) stable system into decompensation, reminiscent of the episodic nature of SDs in various diseases.
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Affiliation(s)
- Clemens Reiffurth
- Department of Experimental Neurology, Charité-University Medicine Berlin, Berlin, Germany.,Center for Stroke Research, Charité-University Medicine Berlin, Berlin, Germany
| | - Mesbah Alam
- Department of Neurosurgery, Hannover Medical School, Hannover, Germany
| | - Mahdi Zahedi-Khorasani
- Research Center and Department of Physiology, School of Medicine, Semnan University of Medical Sciences, Semnan, Iran
| | - Sebastian Major
- Department of Experimental Neurology, Charité-University Medicine Berlin, Berlin, Germany.,Center for Stroke Research, Charité-University Medicine Berlin, Berlin, Germany.,Department of Neurology, Charité-University Medicine Berlin, Berlin, Germany
| | - Jens P Dreier
- Department of Experimental Neurology, Charité-University Medicine Berlin, Berlin, Germany.,Center for Stroke Research, Charité-University Medicine Berlin, Berlin, Germany.,Department of Neurology, Charité-University Medicine Berlin, Berlin, Germany.,Bernstein Center for Computational Neuroscience Berlin, Berlin, Germany.,Einstein Center for Neurosciences Berlin, Berlin, Germany
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25
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Gerzson MFB, Bona NP, Soares MSP, Teixeira FC, Rahmeier FL, Carvalho FB, da Cruz Fernandes M, Onzi G, Lenz G, Gonçales RA, Spanevello RM, Stefanello FM. Tannic Acid Ameliorates STZ-Induced Alzheimer's Disease-Like Impairment of Memory, Neuroinflammation, Neuronal Death and Modulates Akt Expression. Neurotox Res 2020; 37:1009-1017. [PMID: 31997154 DOI: 10.1007/s12640-020-00167-3] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2019] [Revised: 12/18/2019] [Accepted: 01/22/2020] [Indexed: 12/28/2022]
Abstract
Tannic acid (TA) is a hydrolysable glycosidic polyphenol polymer of gallic acid, which possesses neuroprotective properties. The aim of this study was to evaluate the effect of TA treatment on cognitive performance and neurochemical changes in an experimental model of sporadic dementia of Alzheimer's type (SDAT) induced by intracerebroventricular (ICV) injection of streptozotocin (STZ) and to explore the potential cellular and molecular mechanisms underlying these effects. Adult male rats were divided into four groups: control, TA, STZ, and TA + STZ. Animals from TA and TA + STZ groups were treated with TA (30 mg/kg) daily, by gavage, for 21 days; others groups received water (1 mL/kg). Subsequently, an ICV injection of STZ (3 mg/kg) was administered into the lateral ventricles of animals from STZ and TA + STZ groups, while other groups received citrate buffer. Cognitive deficits (short-term memory), neuronal survival, neuroinflammation as well as expression of SNAP-25, Akt, and pAkt were evaluated in the cerebral cortex. TA treatment protected against the impairment of memory in STZ-induced SDAT. STZ promoted an increase in neuronal death and the levels of proinflammatory cytokines (IL-6 and TNF-α) and a decrease in Akt and pAkt expression; TA was able to restore these changes. Neither STZ nor TA altered SNAP-25 expression or the levels of IL-12 and IL-4 in the cerebral cortex. Our study highlights that treatment with TA prevents memory deficits and reestablishes Akt and pAkt expression, protecting against neuronal death and neuroinflammation in STZ-induced SDAT in rats.
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Affiliation(s)
- Mariana F B Gerzson
- Laboratório de Biomarcadores, Centro de Ciências Químicas, Farmacêuticas e de Alimentos, Universidade Federal de Pelotas, Campus Universitário s/n, Pelotas, RS, Brazil
| | - Natália P Bona
- Laboratório de Biomarcadores, Centro de Ciências Químicas, Farmacêuticas e de Alimentos, Universidade Federal de Pelotas, Campus Universitário s/n, Pelotas, RS, Brazil
| | - Mayara S P Soares
- Laboratório de Neuroquímica, Inflamação e Câncer, Centro de Ciências Químicas, Farmacêuticas e de Alimentos, Universidade Federal de Pelotas, Campus Universitário s/n, Pelotas, RS, Brazil
| | - Fernanda C Teixeira
- Laboratório de Neuroquímica, Inflamação e Câncer, Centro de Ciências Químicas, Farmacêuticas e de Alimentos, Universidade Federal de Pelotas, Campus Universitário s/n, Pelotas, RS, Brazil
| | - Francine L Rahmeier
- Laboratório de Pesquisa em Patologia, Universidade Federal de Ciências da Saúde de Porto Alegre, Rua Sarmento Leite, 245, Porto Alegre, RS, Brazil
| | - Fabiano B Carvalho
- Laboratório de Pesquisa em Patologia, Universidade Federal de Ciências da Saúde de Porto Alegre, Rua Sarmento Leite, 245, Porto Alegre, RS, Brazil
| | - Marilda da Cruz Fernandes
- Laboratório de Pesquisa em Patologia, Universidade Federal de Ciências da Saúde de Porto Alegre, Rua Sarmento Leite, 245, Porto Alegre, RS, Brazil
| | - Giovana Onzi
- Laboratório de Sinalização e Plasticidade Celular, Departamento de Biofísica, Universidade Federal do Rio Grande do Sul , Porto Alegre, RS, Brazil
| | - Guido Lenz
- Laboratório de Sinalização e Plasticidade Celular, Departamento de Biofísica, Universidade Federal do Rio Grande do Sul , Porto Alegre, RS, Brazil
| | - Relber A Gonçales
- Laboratório de Biologia Molecular, Universidade Federal de Goiás, Goiânia, GO, Brazil
| | - Roselia M Spanevello
- Laboratório de Neuroquímica, Inflamação e Câncer, Centro de Ciências Químicas, Farmacêuticas e de Alimentos, Universidade Federal de Pelotas, Campus Universitário s/n, Pelotas, RS, Brazil.
| | - Francieli M Stefanello
- Laboratório de Biomarcadores, Centro de Ciências Químicas, Farmacêuticas e de Alimentos, Universidade Federal de Pelotas, Campus Universitário s/n, Pelotas, RS, Brazil.
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26
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Abnormal neurovascular coupling as a cause of excess cerebral vasodilation in familial migraine. Cardiovasc Res 2019; 116:2009-2020. [DOI: 10.1093/cvr/cvz306] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/21/2019] [Revised: 10/16/2019] [Accepted: 11/07/2019] [Indexed: 12/27/2022] Open
Abstract
Abstract
Aims
Acute migraine attack in familial hemiplegic migraine type 2 (FHM2) patients is characterized by sequential hypo- and hyperperfusion. FHM2 is associated with mutations in the Na, K-ATPase α2 isoform. Heterozygous mice bearing one of these mutations (α2+/G301R mice) were shown to have elevated cerebrovascular tone and, thus, hypoperfusion that might lead to elevated concentrations of local metabolites. We hypothesize that these α2+/G301R mice also have increased cerebrovascular hyperaemic responses to these local metabolites leading to hyperperfusion in the affected part of the brain.
Methods and results
Neurovascular coupling was compared in α2+/G301R and matching wild-type (WT) mice using Laser Speckle Contrast Imaging. In brain slices, parenchymal arteriole diameter and intracellular calcium changes in neuronal tissue, astrocytic endfeet, and smooth muscle cells in response to neuronal excitation were assessed. Wall tension and smooth muscle membrane potential were measured in isolated middle cerebral arteries. Quantitative polymerase chain reaction, western blot, and immunohistochemistry were used to assess the molecular background underlying the functional changes. Whisker stimulation induced larger increase in blood perfusion, i.e. hyperaemic response, of the somatosensory cortex of α2+/G301R than WT mice. Neuronal excitation was associated with larger parenchymal arteriole dilation in brain slices from α2+/G301R than WT mice. These hyperaemic responses in vivo and ex vivo were inhibited by BaCl2, suggesting involvement of inward-rectifying K+ channels (Kir). Relaxation to elevated bath K+ was larger in arteries from α2+/G301R compared to WT mice. This difference was endothelium-dependent. Endothelial Kir2.1 channel expression was higher in arteries from α2+/G301R mice. No sex difference in functional responses and Kir2.1 expression was found.
Conclusion
This study suggests that an abnormally high cerebrovascular hyperaemic response in α2+/G301R mice is a result of increased endothelial Kir2.1 channel expression. This may be initiated by vasospasm-induced accumulation of local metabolites and underlie the hyperperfusion seen in FHM2 patients during migraine attack.
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27
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Pietrobon D, Brennan KC. Genetic mouse models of migraine. J Headache Pain 2019; 20:79. [PMID: 31299902 PMCID: PMC6734414 DOI: 10.1186/s10194-019-1029-5] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2019] [Accepted: 06/27/2019] [Indexed: 12/25/2022] Open
Abstract
Mouse models of rare monogenic forms of migraine provide a unique experimental system to study the cellular and circuit mechanisms of the primary brain dysfunctions causing a migraine disorder. Here, we discuss the migraine-relevant phenotypes and the migraine-relevant functional alterations in the brain of five genetic mouse models of migraine, four of which carry mutations derived from patients with familial hemiplegic migraine (FHM) and the fifth carry a mutation from patients with both phenotypically normal MA and familial advanced sleep phase syndrome (FASPS). We focus on the latter mouse model, in which a ubiquitous serine-threonine kinase is mutated, and on two mouse models of pure FHM, in which a voltage-gated calcium channel controlling neurotransmitter release at most brain synapses and a Na/K ATPase that is expressed mainly in astrocytes in the adult brain are mutated, respectively. First, we describe the behavioral phenotypes of the genetic animal models and review the evidence that an increased susceptibility to experimentally induced cortical spreading depression (CSD) is a key migraine-relevant phenotype common to the five models. Second, we review the synaptic alterations in the cerebral cortex of the genetic models of migraine and discuss the mechanisms underlying their increased susceptibility to CSD. Third, we review the alterations in the trigeminovascular pain pathway and discuss possible implications for migraine pain mechanisms. Finally, we discuss the insights into migraine pathophysiology obtained from the genetic models of migraine, in particular regarding the mechanisms that make the brain of migraineurs susceptible to the ignition of “spontaneous” CSDs. Although the reviewed functional studies support the view of migraine as a disorder of the brain characterized by dysfunctional regulation of the excitatory/inhibitory balance in specific neuronal circuits, much work remains to be done in the genetic mouse models e.g. to identfy the relevant dysfunctional circuits and to establish whether and how the alterations in the function of specific circuits (in the cerebral cortex and/or other brain areas) are state-dependent and may, in certain conditions, favor CSD ignition and the migraine attack.
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Affiliation(s)
- Daniela Pietrobon
- Department of Biomedical Sciences and Padova Neuroscience Center, University of Padova, 35131, Padova, Italy. .,CNR Institute of Neuroscience, 35131, Padova, Italy.
| | - K C Brennan
- Department of Neurology, University of Utah, Salt Lake City, Utah, USA.
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28
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Differential expression patterns of sodium potassium ATPase alpha and beta subunit isoforms in mouse brain during postnatal development. Neurochem Int 2019; 128:163-174. [PMID: 31009649 DOI: 10.1016/j.neuint.2019.04.009] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2018] [Revised: 04/05/2019] [Accepted: 04/15/2019] [Indexed: 11/21/2022]
Abstract
The sodium potassium ATPase (Na+/K+ ATPase) is essential for the maintenance of a low intracellular Na+ and a high intracellular K+ concentration. Loss of function of the Na+/K+ ATPase due to mutations in Na+/K+ ATPase genes, anoxic conditions, depletion of ATP or inhibition of the Na+/K+ ATPase function using cardiac glycosides such as digitalis, causes a depolarization of the resting membrane potential. While in non-excitable cells, the uptake of glucose and amino acids is decreased if the function of the Na+/K+ ATPase is compromised, in excitable cells the symptoms range from local hyper-excitability to inactivating depolarization. Although several studies have demonstrated the differential expression of the various Na+/K+ ATPase alpha and beta isoforms in the brain tissue of rodents, their expression profile during development has yet to be thoroughly investigated. An immunohistochemical analysis of postnatal day 19 mouse brain showed ubiquitous expression of Na+/K+ ATPase isoforms α1, β1 and β2 in both neurons and glial cells, whereas α2 was expressed mostly in glial cells and the α3 and β3 isoforms were expressed in neurons. Furthermore, we examined potential changes in the relative expression of the different Na+/K+ ATPase isoforms in different brain areas of postnatal day 6 and in adult 9 months old animals using immunoblot analysis. Our results show a significant up-regulation of the α1 isoform in cortex, hippocampus and cerebellum, whereas, the α2 isoform was significantly up-regulated in midbrain. The β3 isoform showed a significant up-regulation in all brain areas investigated. The up-regulation of the α3 isoform matched that of the β2 isoform which were both significantly up-regulated in cortex, hippocampus and midbrain, suggesting that the increased maturation of the neuronal network is accompanied by an increase in expression of α3/β2 complexes in these brain structures.
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Li XC, Zheng X, Chen X, Zhao C, Zhu D, Zhang J, Zhuo JL. Genetic and genomic evidence for an important role of the Na +/H + exchanger 3 in blood pressure regulation and angiotensin II-induced hypertension. Physiol Genomics 2019; 51:97-108. [PMID: 30849009 PMCID: PMC6485378 DOI: 10.1152/physiolgenomics.00122.2018] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023] Open
Abstract
The sodium (Na+)/hydrogen (H+) exchanger 3 (NHE3) and sodium-potassium adenosine triphosphatase (Na+/K+-ATPase) are two of the most important Na+ transporters in the proximal tubules of the kidney. On the apical membrane side, NHE3 primarily mediates the entry of Na+ into and the exit of H+ from the proximal tubules, directly and indirectly being responsible for reabsorbing ~50% of filtered Na+ in the proximal tubules of the kidney. On the basolateral membrane side, Na+/K+-ATPase serves as a powerful engine driving Na+ out of, while pumping K+ into the proximal tubules against their concentration gradients. While the roles of NHE3 and Na+/K+-ATPase in proximal tubular Na+ transport under in vitro conditions are well recognized, their respective contributions to the basal blood pressure regulation and angiotensin II (ANG II)-induced hypertension remain poorly understood. Recently, we have been fortunate to be able to use genetically modified mouse models with global, kidney- or proximal tubule-specific deletion of NHE3 to directly determine the cause and effect relationship between NHE3, basal blood pressure homeostasis, and ANG II-induced hypertension at the whole body, kidney and/or proximal tubule levels. The purpose of this article is to review the genetic and genomic evidence for an important role of NHE3 with a focus in the regulation of basal blood pressure and ANG II-induced hypertension, as we learned from studies using global, kidney- or proximal tubule-specific NHE3 knockout mice. We hypothesize that NHE3 in the proximal tubules is necessary for maintaining basal blood pressure homeostasis and the development of ANG II-induced hypertension.
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Affiliation(s)
- Xiao C Li
- Laboratory of Receptor and Signal Transduction, Department of Pharmacology and Toxicology; Division of Nephrology, Internal Medicine; Cardiovascular and Renal Research Center; The University of Mississippi Medical Center , Jackson, Mississippi
| | - Xiaowen Zheng
- Laboratory of Receptor and Signal Transduction, Department of Pharmacology and Toxicology; Division of Nephrology, Internal Medicine; Cardiovascular and Renal Research Center; The University of Mississippi Medical Center , Jackson, Mississippi
| | - Xu Chen
- Laboratory of Receptor and Signal Transduction, Department of Pharmacology and Toxicology; Division of Nephrology, Internal Medicine; Cardiovascular and Renal Research Center; The University of Mississippi Medical Center , Jackson, Mississippi
| | - Chunling Zhao
- Laboratory of Receptor and Signal Transduction, Department of Pharmacology and Toxicology; Division of Nephrology, Internal Medicine; Cardiovascular and Renal Research Center; The University of Mississippi Medical Center , Jackson, Mississippi
| | - Dongmin Zhu
- Laboratory of Receptor and Signal Transduction, Department of Pharmacology and Toxicology; Division of Nephrology, Internal Medicine; Cardiovascular and Renal Research Center; The University of Mississippi Medical Center , Jackson, Mississippi
| | - Jianfeng Zhang
- Laboratory of Receptor and Signal Transduction, Department of Pharmacology and Toxicology; Division of Nephrology, Internal Medicine; Cardiovascular and Renal Research Center; The University of Mississippi Medical Center , Jackson, Mississippi
| | - Jia L Zhuo
- Laboratory of Receptor and Signal Transduction, Department of Pharmacology and Toxicology; Division of Nephrology, Internal Medicine; Cardiovascular and Renal Research Center; The University of Mississippi Medical Center , Jackson, Mississippi
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Key J, Mueller AK, Gispert S, Matschke L, Wittig I, Corti O, Münch C, Decher N, Auburger G. Ubiquitylome profiling of Parkin-null brain reveals dysregulation of calcium homeostasis factors ATP1A2, Hippocalcin and GNA11, reflected by altered firing of noradrenergic neurons. Neurobiol Dis 2019; 127:114-130. [PMID: 30763678 DOI: 10.1016/j.nbd.2019.02.008] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2018] [Revised: 12/05/2018] [Accepted: 02/08/2019] [Indexed: 02/06/2023] Open
Abstract
Parkinson's disease (PD) is the second most frequent neurodegenerative disorder in the old population. Among its monogenic variants, a frequent cause is a mutation in the Parkin gene (Prkn). Deficient function of Parkin triggers ubiquitous mitochondrial dysfunction and inflammation in the brain, but it remains unclear how selective neural circuits become vulnerable and finally undergo atrophy. We attempted to go beyond previous work, mostly done in peripheral tumor cells, which identified protein targets of Parkin activity, an ubiquitin E3 ligase. Thus, we now used aged Parkin-knockout (KO) mouse brain for a global quantification of ubiquitylated peptides by mass spectrometry (MS). This approach confirmed the most abundant substrate to be VDAC3, a mitochondrial outer membrane porin that modulates calcium flux, while uncovering also >3-fold dysregulations for neuron-specific factors. Ubiquitylation decreases were prominent for Hippocalcin (HPCA), Calmodulin (CALM1/CALML3), Pyruvate Kinase (PKM2), sodium/potassium-transporting ATPases (ATP1A1/2/3/4), the Rab27A-GTPase activating protein alpha (TBC1D10A) and an ubiquitin ligase adapter (DDB1), while strong increases occurred for calcium transporter ATP2C1 and G-protein subunits G(i)/G(o)/G(Tr). Quantitative immunoblots validated elevated abundance for the electrogenic pump ATP1A2, for HPCA as neuron-specific calcium sensor, which stimulates guanylate cyclases and modifies axonal slow afterhyperpolarization (sAHP), and for the calcium-sensing G-protein GNA11. We assessed if compensatory molecular regulations become insufficient over time, leading to functional deficits. Patch clamp experiments in acute Parkin-KO brain slices indeed revealed alterations of the electrophysiological properties in aged noradrenergic locus coeruleus (LC) neurons. LC neurons of aged Parkin-KO brain showed an acceleration of the spontaneous pacemaker frequency, a reduction in sAHP and shortening of action potential duration, without modulation of KCNQ potassium currents. These findings indicate altered calcium-dependent excitability in a PARK2 model of PD, mediated by diminished turnover of potential Parkin targets such as ATP1A2 and HPCA. The data also identified further novel Parkin substrate candidates like SIRT2, OTUD7B and CUL5. Our elucidation of neuron-specific mechanisms of PD pathogenesis helps to explain the known exceptional susceptibility of noradrenergic and dopaminergic projections to alterations of calcium homeostasis and its mitochondrial buffering.
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Affiliation(s)
- J Key
- Exp. Neurology, Goethe University Medical School, 60590 Frankfurt am Main, Germany
| | - A K Mueller
- Institute for Physiology and Pathophysiology, Vegetative Physiology and Marburg Center for Mind, Brain and Behavior - MCMBB; Clinic for Neurology, Philipps-University Marburg, 35037 Marburg, Germany
| | - S Gispert
- Exp. Neurology, Goethe University Medical School, 60590 Frankfurt am Main, Germany
| | - L Matschke
- Institute for Physiology and Pathophysiology, Vegetative Physiology and Marburg Center for Mind, Brain and Behavior - MCMBB; Clinic for Neurology, Philipps-University Marburg, 35037 Marburg, Germany
| | - I Wittig
- Functional Proteomics, SFB 815 Core Unit, Goethe University Medical School, 60590 Frankfurt am Main, Germany
| | - O Corti
- Institut du Cerveau et de la Moelle épinière, ICM, Paris, F-75013, France; Inserm, U1127, Paris, F-75013, France; CNRS, UMR 7225, Paris, F-75013, France; Sorbonne Universités, Paris, F-75013, France
| | - C Münch
- Institute of Biochemistry II, Goethe University Medical School, 60590 Frankfurt am Main, Germany
| | - N Decher
- Institute for Physiology and Pathophysiology, Vegetative Physiology and Marburg Center for Mind, Brain and Behavior - MCMBB; Clinic for Neurology, Philipps-University Marburg, 35037 Marburg, Germany.
| | - G Auburger
- Exp. Neurology, Goethe University Medical School, 60590 Frankfurt am Main, Germany.
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Sweadner KJ, Arystarkhova E, Penniston JT, Swoboda KJ, Brashear A, Ozelius LJ. Genotype-structure-phenotype relationships diverge in paralogs ATP1A1, ATP1A2, and ATP1A3. NEUROLOGY-GENETICS 2019; 5:e303. [PMID: 30842972 PMCID: PMC6384024 DOI: 10.1212/nxg.0000000000000303] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/01/2018] [Accepted: 11/08/2018] [Indexed: 11/15/2022]
Abstract
Objective We tested the assumption that closely related genes should have similar pathogenic variants by analyzing >200 pathogenic variants in a gene family with high neurologic impact and high sequence identity, the Na,K-ATPases ATP1A1, ATP1A2, and ATP1A3. Methods Data sets of disease-associated variants were compared. Their equivalent positions in protein crystal structures were used for insights into pathogenicity and correlated with the phenotype and conservation of homology. Results Relatively few mutations affected the corresponding amino acids in 2 genes. In the membrane domain of ATP1A3 (primarily expressed in neurons), variants producing milder neurologic phenotypes had different structural positions than variants producing severe phenotypes. In ATP1A2 (primarily expressed in astrocytes), membrane domain variants characteristic of severe phenotypes in ATP1A3 were absent from patient data. The known variants in ATP1A1 fell into 2 distinct groups. Sequence conservation was an imperfect indicator: it varied among structural domains, and some variants with demonstrated pathogenicity were in low conservation sites. Conclusions Pathogenic variants varied between genes despite high sequence identity, and there is a genotype-structure-phenotype relationship in ATP1A3 that correlates with neurologic outcomes. The absence of "severe" pathogenic variants in ATP1A2 patients predicts that they will manifest either in a different tissue or by death in utero and that new ATP1A1 variants will produce additional phenotypes. It is important that some variants in poorly conserved amino acids are nonetheless pathogenic and could be incorrectly predicted to be benign.
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Affiliation(s)
- Kathleen J Sweadner
- Department of Neurosurgery (K.J. Sweadner, E.A., J.T.P.), Center for Human Genetics Research (K.J. Swoboda), and Department of Neurology, (K.J. Swoboda, L.J.O.) Massachusetts General Hospital, Boston; and the Department of Neurology (A.B.), Wake Forest School of Medicine, Winston-Salem, NC
| | - Elena Arystarkhova
- Department of Neurosurgery (K.J. Sweadner, E.A., J.T.P.), Center for Human Genetics Research (K.J. Swoboda), and Department of Neurology, (K.J. Swoboda, L.J.O.) Massachusetts General Hospital, Boston; and the Department of Neurology (A.B.), Wake Forest School of Medicine, Winston-Salem, NC
| | - John T Penniston
- Department of Neurosurgery (K.J. Sweadner, E.A., J.T.P.), Center for Human Genetics Research (K.J. Swoboda), and Department of Neurology, (K.J. Swoboda, L.J.O.) Massachusetts General Hospital, Boston; and the Department of Neurology (A.B.), Wake Forest School of Medicine, Winston-Salem, NC
| | - Kathryn J Swoboda
- Department of Neurosurgery (K.J. Sweadner, E.A., J.T.P.), Center for Human Genetics Research (K.J. Swoboda), and Department of Neurology, (K.J. Swoboda, L.J.O.) Massachusetts General Hospital, Boston; and the Department of Neurology (A.B.), Wake Forest School of Medicine, Winston-Salem, NC
| | - Allison Brashear
- Department of Neurosurgery (K.J. Sweadner, E.A., J.T.P.), Center for Human Genetics Research (K.J. Swoboda), and Department of Neurology, (K.J. Swoboda, L.J.O.) Massachusetts General Hospital, Boston; and the Department of Neurology (A.B.), Wake Forest School of Medicine, Winston-Salem, NC
| | - Laurie J Ozelius
- Department of Neurosurgery (K.J. Sweadner, E.A., J.T.P.), Center for Human Genetics Research (K.J. Swoboda), and Department of Neurology, (K.J. Swoboda, L.J.O.) Massachusetts General Hospital, Boston; and the Department of Neurology (A.B.), Wake Forest School of Medicine, Winston-Salem, NC
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Floyd RV, Mobasheri A, Wray S. Gestation changes sodium pump isoform expression, leading to changes in ouabain sensitivity, contractility, and intracellular calcium in rat uterus. Physiol Rep 2018; 5. [PMID: 29208689 PMCID: PMC5727280 DOI: 10.14814/phy2.13527] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2017] [Revised: 10/30/2017] [Accepted: 11/01/2017] [Indexed: 11/24/2022] Open
Abstract
Developmental and tissue‐specific differences in isoforms allow Na+, K+‐ATPase function to be tightly regulated, as they control sensitivity to ions and inhibitors. Uterine contraction relies on the activity of the Na+, K+ATPase, which creates ionic gradients that drive excitation‐contraction coupling. It is unknown whether Na+, K+ATPase isoforms are regulated throughout pregnancy or whether they have a direct role in modulating uterine contractility. We hypothesized that gestation‐dependent differential expression of isoforms would affect contractile responses to Na+, K+ATPase α subunit inhibition with ouabain. Our aims were therefore: (1) to determine the gestation‐dependent expression of mRNA transcripts, protein abundance and tissue distribution of Na+, K+ATPase isoforms in myometrium; (2) to investigate the functional effects of differential isoform expression via ouabain sensitivity; and (3) if changes in contractile responses can be explained by changes in intracellular [Ca2+]. Changes in abundance and distribution of the Na+, K+ATPase α, β and FXYD1 and 2 isoforms, were studied in rat uterus from nonpregnant, and early, mid‐, and term gestation. All α, β subunit isoforms (1,2,3) and FXYD1 were detected but FXYD2 was absent. The α1 and β1 isoforms were unchanged throughout pregnancy, whereas α2 and α3 significant decreased at term while β2 and FXYD1 significantly increased from mid‐term onwards. These changes in expression correlated with increased functional sensitivity to ouabain, and parallel changes in intracellular Ca2+, measured with Indo‐1. In conclusion, gestation induces specific regulatory changes in expression of Na+, K+ATPase isoforms in the uterus which influence contractility and may be related to the physiological requirements for successful pregnancy and delivery.
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Affiliation(s)
- Rachel V Floyd
- The Department of Molecular and Cellular Physiology, University of Liverpool, Liverpool, United Kingdom
| | - Ali Mobasheri
- Department of Veterinary Preclinical Sciences, School of Veterinary Medicine, Faculty of Health and Medical Sciences, University of Surrey, Guildford, United Kingdom
| | - Susan Wray
- The Department of Molecular and Cellular Physiology, University of Liverpool, Liverpool, United Kingdom
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Kaur R, Sharma A, Sodhi M, Swami SK, Sharma VL, Kumari P, Verma P, Mukesh M. Sequence characterization of alpha 1 isoform (ATP1A1) of Na+/K+-ATPase gene and expression characteristics of its major isoforms across tissues of riverine buffaloes (Bubalus bubalis). GENE REPORTS 2018. [DOI: 10.1016/j.genrep.2017.11.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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Abstract
Oncotic cell death or oncosis represents a major mechanism of cell death in ischaemic stroke, occurring in many central nervous system (CNS) cell types including neurons, glia and vascular endothelial cells. In stroke, energy depletion causes ionic pump failure and disrupts ionic homeostasis. Imbalance between the influx of Na+ and Cl- ions and the efflux of K+ ions through various channel proteins and transporters creates a transmembrane osmotic gradient, with ensuing movement of water into the cells, resulting in cell swelling and oncosis. Oncosis is a key mediator of cerebral oedema in ischaemic stroke, contributing directly through cytotoxic oedema, and indirectly through vasogenic oedema by causing vascular endothelial cell death and disruption of the blood-brain barrier (BBB). Hence, inhibition of uncontrolled ionic flux represents a novel and powerful strategy in achieving neuroprotection in stroke. In this review, we provide an overview of oncotic cell death in the pathology of stroke. Importantly, we summarised the therapeutically significant pathways of water, Na+, Cl- and K+ movement across cell membranes in the CNS and their respective roles in the pathobiology of stroke.
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Hu HJ, Song M. Disrupted Ionic Homeostasis in Ischemic Stroke and New Therapeutic Targets. J Stroke Cerebrovasc Dis 2017; 26:2706-2719. [PMID: 29054733 DOI: 10.1016/j.jstrokecerebrovasdis.2017.09.011] [Citation(s) in RCA: 46] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2017] [Revised: 08/30/2017] [Accepted: 09/06/2017] [Indexed: 12/31/2022] Open
Abstract
BACKGROUND Stroke is a leading cause of long-term disability. All neuroprotectants targeting excitotoxicity have failed to become stroke medications. In order to explore and identify new therapeutic targets for stroke, we here reviewed present studies of ionic transporters and channels that are involved in ischemic brain damage. METHOD We surveyed recent literature from animal experiments and clinical reports in the databases of PubMed and Elsevier ScienceDirect to analyze ionic mechanisms underlying ischemic cell damage and suggest promising ideas for stroke therapy. RESULTS Dysfunction of ionic transporters and disrupted ionic homeostasis are most early changes that underlie ischemic brain injury, thus receiving sustained attention in translational stroke research. The Na+/K+-ATPase, Na+/Ca2+ Exchanger, ionotropic glutamate receptor, acid-sensing ion channels (ASICs), sulfonylurea receptor isoform 1 (SUR1)-regulated NCCa-ATP channels, and transient receptor potential (TRP) channels are critically involved in ischemia-induced cellular degenerating processes such as cytotoxic edema, excitotoxicity, necrosis, apoptosis, and autophagic cell death. Some ionic transporters/channels also act as signalosomes to regulate cell death signaling. For acute stroke treatment, glutamate-mediated excitotoxicity must be interfered within 2 hours after stroke. The SUR1-regulated NCCa-ATP channels, Na+/K+-ATPase, ASICs, and TRP channels have a much longer therapeutic window, providing new therapeutic targets for developing feasible pharmacological treatments toward acute ischemic stroke. CONCLUSION The next generation of stroke therapy can apply a polypharmacology strategy for which drugs are designed to target multiple ion transporters/channels or their interaction with neurotoxic signaling pathways. But a successful translation of neuroprotectants relies on in-depth analyses of cell death mechanisms and suitable animal models resembling human stroke.
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Affiliation(s)
- Hui-Jie Hu
- Department of Pharmacology, Institute of Medical Sciences, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Mingke Song
- Department of Pharmacology, Institute of Medical Sciences, Shanghai Jiao Tong University School of Medicine, Shanghai, China.
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Ikeda K, Onimaru H, Kawakami K. Knockout of sodium pump α3 subunit gene ( Atp1a3 −/− ) results in perinatal seizure and defective respiratory rhythm generation. Brain Res 2017; 1666:27-37. [DOI: 10.1016/j.brainres.2017.04.014] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2016] [Revised: 04/02/2017] [Accepted: 04/21/2017] [Indexed: 10/19/2022]
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Hertz L, Chen Y. Glycogenolysis, an Astrocyte-Specific Reaction, is Essential for Both Astrocytic and Neuronal Activities Involved in Learning. Neuroscience 2017; 370:27-36. [PMID: 28668486 DOI: 10.1016/j.neuroscience.2017.06.025] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2017] [Revised: 06/10/2017] [Accepted: 06/19/2017] [Indexed: 01/26/2023]
Abstract
In brain glycogen, formed from glucose, is degraded (glycogenolysis) in astrocytes but not in neurons. Although most of the degradation follows the same pathway as glucose, its breakdown product, l-lactate, is released from astrocytes in larger amounts than glucose when glycogenolysis is activated by noradrenaline. However, this is not the case when glycogenolysis is activated by high potassium ion (K+) concentrations - possibly because noradrenaline in contrast to high K+ stimulates glycogenolysis by an increase not only in free cytosolic Ca2+ concentration ([Ca2+]i) but also in cyclic AMP (c-AMP), which may increase the expression of the monocarboxylate transporter through which it is released. Several transmitters activate glycogenolysis in astrocytes and do so at different time points after training. This stimulation is essential for memory consolidation because glycogenolysis is necessary for uptake of K+ and stimulates formation of glutamate from glucose, and therefore is needed both for removal of increased extracellular K+ following neuronal excitation (which initially occurs into astrocytes) and for formation of transmitter glutamate and GABA. In addition the released l-lactate has effects on neurons which are essential for learning and for learning-related long-term potentiation (LTP), including induction of the neuronal gene Arc/Arg3.1 and activation of gene cascades mediated by CREB and cofilin. Inhibition of glycogenolysis blocks learning, LTP and all related molecular events, but all changes can be reversed by injection of l-lactate. The effect of extracellular l-lactate is due to both astrocyte-mediated signaling which activates noradrenergic activity on all brain cells and to a minor uptake, possibly into dendritic spines.
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Affiliation(s)
- Leif Hertz
- Laboratory of Metabolic Brain Diseases, Institute of Metabolic Disease Research and Drug Development, China Medical University, Shenyang, PR China
| | - Ye Chen
- Henry M. Jackson Foundation, Bethesda, MD 20817, USA.
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Hertz L, Chen Y. Importance of astrocytes for potassium ion (K+) homeostasis in brain and glial effects of K+ and its transporters on learning. Neurosci Biobehav Rev 2016; 71:484-505. [DOI: 10.1016/j.neubiorev.2016.09.018] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2016] [Revised: 08/12/2016] [Accepted: 09/23/2016] [Indexed: 10/20/2022]
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Atp1a2 contributes modestly to alcohol-related behaviors. Alcohol 2016; 56:29-37. [PMID: 27814792 DOI: 10.1016/j.alcohol.2016.09.029] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2016] [Revised: 09/06/2016] [Accepted: 09/12/2016] [Indexed: 01/02/2023]
Abstract
Atp1a2 has been previously studied for anxiety, learning and motor function disorders, and fear. Since Atp1a2 has been shown to be involved in anxiety and this behavior is a known risk factor for developing alcoholism, we have been investigating Atp1a2 for its potential role in responses to alcohol. This study utilized Atp1a2 knockout mice; Atp1a2 heterozygous mice, with half the amount of protein compared to wild-type mice, were used because Atp1a2 homozygous null mice die shortly after birth. The alcohol-related behavioral experiments performed were loss of righting reflex (LORR), acute alcohol withdrawal measured by handling-induced convulsions (HIC), drinking in the dark (DID), open-field activity (OFA), and elevated plus-maze (EPM). LORR was a 2-day test that measures acute alcohol sensitivity, and rapid and acute functional tolerance (AFT). HIC was a 3-day test to measure alcohol withdrawal, DID was a 4-day test which measures voluntary alcohol consumption, and OFA and EPM measured anxiety with alcohol exposure. The effect of genotype on alcohol metabolism was also examined. There was a genotype effect on rate of alcohol metabolism, but only in males. There was no effect on alcohol withdrawal severity. The Atp1a2 heterozygous mice consumed more alcohol than wild-type mice in the DID test, although only in males. In addition, only males were observed to show rapid tolerance in the LORR test while only female heterozygous mice showed a pretreatment effect on AFT. Alcohol exposure had a greater anxiolytic effect in the heterozygous mice compared to wild-type mice, although, again, there were sex effects with only males showing the effect in OFA and only females in the EPM. Although the behavioral results were mixed, there does appear to be a connection between anxiety and alcohol. Overall, the results suggest that Atp1a2 does contribute to alcohol-related behaviors, although the effect is modest with a clear dependence on sex.
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Properties of Na,K-ATPase in cerebellum of male and female rats: effects of acute and prolonged diabetes. Mol Cell Biochem 2016; 425:25-36. [DOI: 10.1007/s11010-016-2859-y] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2016] [Accepted: 10/22/2016] [Indexed: 02/07/2023]
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Stanley CM, Gagnon DG, Bernal A, Meyer DJ, Rosenthal JJ, Artigas P. Importance of the Voltage Dependence of Cardiac Na/K ATPase Isozymes. Biophys J 2016; 109:1852-62. [PMID: 26536262 DOI: 10.1016/j.bpj.2015.09.015] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2015] [Revised: 08/11/2015] [Accepted: 09/10/2015] [Indexed: 11/25/2022] Open
Abstract
Cardiac cells express more than one isoform of the Na, K-ATPase (NKA), the heteromeric enzyme that creates the Na(+) and K(+) gradients across the plasmalemma. Cardiac isozymes contain one catalytic α-subunit isoform (α1, α2, or α3) associated with an auxiliary β-subunit isoform (β1 or β2). Past studies using biochemical approaches have revealed minor kinetic differences between isozymes formed by different α-β isoform combinations; these results make it difficult to understand the physiological requirement for multiple isoforms. In intact cells, however, NKA enzymes operate in a more complex environment, which includes a substantial transmembrane potential. We evaluated the voltage dependence of human cardiac NKA isozymes expressed in Xenopus oocytes, and of native NKA isozymes in rat ventricular myocytes, using normal mammalian physiological concentrations of Na(+)o and K(+)o. We demonstrate that although α1 and α3 pumps are functional at all physiologically relevant voltages, α2β1 pumps and α2β2 pumps are inhibited by ∼75% and ∼95%, respectively, at resting membrane potentials, and only activate appreciably upon depolarization. Furthermore, phospholemman (FXYD1) inhibits pump function without significantly altering the pump's voltage dependence. Our observations provide a simple explanation for the physiological relevance of the α2 subunit (∼20% of total α subunits in rat ventricle): they act as a reserve and are recruited into action for extra pumping during the long-lasting cardiac action potential, where most of the Na(+) entry occurs. This strong voltage dependence of α2 pumps also helps explain how cardiotonic steroids, which block NKA pumps, can be a beneficial treatment for heart failure: by only inhibiting the α2 pumps, they selectively reduce NKA activity during the cardiac action potential, leading to an increase in systolic Ca(2+), due to reduced extrusion through the Na/Ca exchanger, without affecting resting Na(+) and Ca(2+) concentrations.
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Affiliation(s)
- Christopher M Stanley
- Department of Cell Physiology and Molecular Biophysics, Center for Membrane Protein Research, Texas Tech University Health Sciences Center, Lubbock, Texas
| | - Dominique G Gagnon
- Department of Cell Physiology and Molecular Biophysics, Center for Membrane Protein Research, Texas Tech University Health Sciences Center, Lubbock, Texas; Department of Physics, Texas Tech University, Lubbock, Texas
| | - Adam Bernal
- Department of Cell Physiology and Molecular Biophysics, Center for Membrane Protein Research, Texas Tech University Health Sciences Center, Lubbock, Texas
| | - Dylan J Meyer
- Department of Cell Physiology and Molecular Biophysics, Center for Membrane Protein Research, Texas Tech University Health Sciences Center, Lubbock, Texas
| | - Joshua J Rosenthal
- Universidad de Puerto Rico, Recinto de Ciencias Médicas, Instituto de Neurobiología, San Juan, Puerto Rico
| | - Pablo Artigas
- Department of Cell Physiology and Molecular Biophysics, Center for Membrane Protein Research, Texas Tech University Health Sciences Center, Lubbock, Texas.
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Capuani C, Melone M, Tottene A, Bragina L, Crivellaro G, Santello M, Casari G, Conti F, Pietrobon D. Defective glutamate and K+ clearance by cortical astrocytes in familial hemiplegic migraine type 2. EMBO Mol Med 2016; 8:967-86. [PMID: 27354390 PMCID: PMC4967947 DOI: 10.15252/emmm.201505944] [Citation(s) in RCA: 105] [Impact Index Per Article: 13.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Migraine is a common disabling brain disorder. A subtype of migraine with aura (familial hemiplegic migraine type 2: FHM2) is caused by loss‐of‐function mutations in α2 Na+,K+ATPase (α2NKA), an isoform almost exclusively expressed in astrocytes in adult brain. Cortical spreading depression (CSD), the phenomenon that underlies migraine aura and activates migraine headache mechanisms, is facilitated in heterozygous FHM2‐knockin mice with reduced expression of α2NKA. The mechanisms underlying an increased susceptibility to CSD in FHM2 are unknown. Here, we show reduced rates of glutamate and K+ clearance by cortical astrocytes during neuronal activity and reduced density of GLT‐1a glutamate transporters in cortical perisynaptic astrocytic processes in heterozygous FHM2‐knockin mice, demonstrating key physiological roles of α2NKA and supporting tight coupling with GLT‐1a. Using ceftriaxone treatment of FHM2 mutants and partial inhibition of glutamate transporters in wild‐type mice, we obtain evidence that defective glutamate clearance can account for most of the facilitation of CSD initiation in FHM2‐knockin mice, pointing to excessive glutamatergic transmission as a key mechanism underlying the vulnerability to CSD ignition in migraine.
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Affiliation(s)
- Clizia Capuani
- Department of Biomedical Sciences, University of Padova, Padova, Italy
| | - Marcello Melone
- Department of Experimental and Clinical Medicine, Università Politecnica delle Marche, Ancona, Italy Center for Neurobiology of Aging, INRCA IRCCS, Ancona, Italy
| | - Angelita Tottene
- Department of Biomedical Sciences, University of Padova, Padova, Italy
| | - Luca Bragina
- Department of Experimental and Clinical Medicine, Università Politecnica delle Marche, Ancona, Italy Center for Neurobiology of Aging, INRCA IRCCS, Ancona, Italy
| | | | - Mirko Santello
- Institute of Pharmacology and Toxicology, University of Zurich, Zürich, Switzerland
| | - Giorgio Casari
- Vita-Salute San Raffaele University and San Raffaele Scientific Institute, Milano, Italy
| | - Fiorenzo Conti
- Department of Experimental and Clinical Medicine, Università Politecnica delle Marche, Ancona, Italy Center for Neurobiology of Aging, INRCA IRCCS, Ancona, Italy Fondazione di Medicina Molecolare, Università Politecnica delle Marche, Ancona, Italy
| | - Daniela Pietrobon
- Department of Biomedical Sciences, University of Padova, Padova, Italy CNR Institute of Neuroscience, Padova, Italy
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Blaustein MP, Chen L, Hamlyn JM, Leenen FHH, Lingrel JB, Wier WG, Zhang J. Pivotal role of α2 Na + pumps and their high affinity ouabain binding site in cardiovascular health and disease. J Physiol 2016; 594:6079-6103. [PMID: 27350568 DOI: 10.1113/jp272419] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2016] [Accepted: 06/18/2016] [Indexed: 12/13/2022] Open
Abstract
Reduced smooth muscle (SM)-specific α2 Na+ pump expression elevates basal blood pressure (BP) and increases BP sensitivity to angiotensin II (Ang II) and dietary NaCl, whilst SM-α2 overexpression lowers basal BP and decreases Ang II/salt sensitivity. Prolonged ouabain infusion induces hypertension in rodents, and ouabain-resistant mutation of the α2 ouabain binding site (α2R/R mice) confers resistance to several forms of hypertension. Pressure overload-induced heart hypertrophy and failure are attenuated in cardio-specific α2 knockout, cardio-specific α2 overexpression and α2R/R mice. We propose a unifying hypothesis that reconciles these apparently disparate findings: brain mechanisms, activated by Ang II and high NaCl, regulate sympathetic drive and a novel neurohumoral pathway mediated by both brain and circulating endogenous ouabain (EO). Circulating EO modulates ouabain-sensitive α2 Na+ pump activity and Ca2+ transporter expression and, via Na+ /Ca2+ exchange, Ca2+ homeostasis. This regulates sensitivity to sympathetic activity, Ca2+ signalling and arterial and cardiac contraction.
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Affiliation(s)
- Mordecai P Blaustein
- Department of Physiology, University of Maryland School of Medicine, Baltimore, MD, 21201, USA. .,Department of Medicine, University of Maryland School of Medicine, Baltimore, MD, 21201, USA.
| | - Ling Chen
- Department of Physiology, University of Maryland School of Medicine, Baltimore, MD, 21201, USA.,Department of Medicine, University of Maryland School of Medicine, Baltimore, MD, 21201, USA
| | - John M Hamlyn
- Department of Physiology, University of Maryland School of Medicine, Baltimore, MD, 21201, USA
| | - Frans H H Leenen
- Hypertension Unit, University of Ottawa Heart Institute, Ottawa, ON, Canada, K1Y 4W7
| | - Jerry B Lingrel
- Department of Molecular Genetics, Biochemistry and Microbiology, University of Cincinnati College of Medicine, Cincinnati, OH, 45267-0524, USA
| | - W Gil Wier
- Department of Physiology, University of Maryland School of Medicine, Baltimore, MD, 21201, USA
| | - Jin Zhang
- Department of Physiology, University of Maryland School of Medicine, Baltimore, MD, 21201, USA
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44
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Abstract
Migraine is an episodic headache disorder affecting more than 10% of the general population. Migraine arises from a primary brain dysfunction that leads to activation and sensitization of the trigeminovascular system. A major incompletely understood issue in the neurobiology of migraine concerns the molecular and cellular mechanisms that underlie the primary brain dysfunction and lead to activation and sensitization of the trigeminovascular system, thus generating and maintaining migraine pain. Here the author reviews recent discoveries that have advanced our understanding of these mechanisms toward a unifying pathophysiological hypothesis, in which cortical spreading depression (CSD), the phenomenon underlying migraine aura, assumes a key role. In particular, the author discusses the main recent findings in the genetics and neurobiology of familial hemiplegic migraine and the insights they provide into the molecular and cellular mechanisms that may lead to the increased susceptibility of CSD in migraineurs.
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Affiliation(s)
- Daniela Pietrobon
- Department of Biomedical Sciences, University of Padova, Padova, Italy.
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45
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Friedrich T, Tavraz NN, Junghans C. ATP1A2 Mutations in Migraine: Seeing through the Facets of an Ion Pump onto the Neurobiology of Disease. Front Physiol 2016; 7:239. [PMID: 27445835 PMCID: PMC4914835 DOI: 10.3389/fphys.2016.00239] [Citation(s) in RCA: 57] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2016] [Accepted: 06/03/2016] [Indexed: 12/31/2022] Open
Abstract
Mutations in four genes have been identified in familial hemiplegic migraine (FHM), from which CACNA1A (FHM type 1) and SCN1A (FHM type 3) code for neuronal voltage-gated calcium or sodium channels, respectively, while ATP1A2 (FHM type 2) encodes the α2 isoform of the Na(+),K(+)-ATPase's catalytic subunit, thus classifying FHM primarily as an ion channel/ion transporter pathology. FHM type 4 is attributed to mutations in the PRRT2 gene, which encodes a proline-rich transmembrane protein of as yet unknown function. The Na(+),K(+)-ATPase maintains the physiological gradients for Na(+) and K(+) ions and is, therefore, critical for the activity of ion channels and transporters involved neuronal excitability, neurotransmitter uptake or Ca(2+) signaling. Strikingly diverse functional abnormalities have been identified for disease-linked ATP1A2 mutations which frequently lead to changes in the enzyme's voltage-dependent properties, kinetics, or apparent cation affinities, but some mutations are truly deleterious for enzyme function and thus cause full haploinsufficiency. Here, we summarize structural and functional data about the Na(+),K(+)-ATPase available to date and an overview is provided about the particular properties of the α2 isoform that explain its physiological relevance in electrically excitable tissues. In addition, current concepts about the neurobiology of migraine, the correlations between primary brain dysfunction and mechanisms of headache pain generation are described, together with insights gained recently from modeling approaches in computational neuroscience. Then, a survey is given about ATP1A2 mutations implicated in migraine cases as documented in the literature with focus on mutations that were described to completely destroy enzyme function, or lead to misfolded or mistargeted protein in particular model cell lines. We also discuss whether or not there are correlations between these most severe mutational effects and clinical phenotypes. Finally, perspectives for future research on the implications of Na(+),K(+)-ATPase mutations in human pathologies are presented.
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Affiliation(s)
- Thomas Friedrich
- Department of Physical Chemistry/Bioenergetics, Institute of Chemistry, Technical University of BerlinBerlin, Germany
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46
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Kinoshita PF, Leite JA, Orellana AMM, Vasconcelos AR, Quintas LEM, Kawamoto EM, Scavone C. The Influence of Na(+), K(+)-ATPase on Glutamate Signaling in Neurodegenerative Diseases and Senescence. Front Physiol 2016; 7:195. [PMID: 27313535 PMCID: PMC4890531 DOI: 10.3389/fphys.2016.00195] [Citation(s) in RCA: 44] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2016] [Accepted: 05/17/2016] [Indexed: 12/17/2022] Open
Abstract
Decreased Na(+), K(+)-ATPase (NKA) activity causes energy deficiency, which is commonly observed in neurodegenerative diseases. The NKA is constituted of three subunits: α, β, and γ, with four distinct isoforms of the catalytic α subunit (α1-4). Genetic mutations in the ATP1A2 gene and ATP1A3 gene, encoding the α2 and α3 subunit isoforms, respectively can cause distinct neurological disorders, concurrent to impaired NKA activity. Within the central nervous system (CNS), the α2 isoform is expressed mostly in glial cells and the α3 isoform is neuron-specific. Mutations in ATP1A2 gene can result in familial hemiplegic migraine (FHM2), while mutations in the ATP1A3 gene can cause Rapid-onset dystonia-Parkinsonism (RDP) and alternating hemiplegia of childhood (AHC), as well as the cerebellar ataxia, areflexia, pescavus, optic atrophy and sensorineural hearing loss (CAPOS) syndrome. Data indicates that the central glutamatergic system is affected by mutations in the α2 isoform, however further investigations are required to establish a connection to mutations in the α3 isoform, especially given the diagnostic confusion and overlap with glutamate transporter disease. The age-related decline in brain α2∕3 activity may arise from changes in the cyclic guanosine monophosphate (cGMP) and cGMP-dependent protein kinase (PKG) pathway. Glutamate, through nitric oxide synthase (NOS), cGMP and PKG, stimulates brain α2∕3 activity, with the glutamatergic N-methyl-D-aspartate (NMDA) receptor cascade able to drive an adaptive, neuroprotective response to inflammatory and challenging stimuli, including amyloid-β. Here we review the NKA, both as an ion pump as well as a receptor that interacts with NMDA, including the role of NKA subunits mutations. Failure of the NKA-associated adaptive response mechanisms may render neurons more susceptible to degeneration over the course of aging.
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Affiliation(s)
- Paula F. Kinoshita
- Department of Pharmacology, Institute of Biomedical Science, University of São PauloSão Paulo, Brazil
| | - Jacqueline A. Leite
- Department of Pharmacology, Institute of Biomedical Science, University of São PauloSão Paulo, Brazil
| | - Ana Maria M. Orellana
- Department of Pharmacology, Institute of Biomedical Science, University of São PauloSão Paulo, Brazil
| | - Andrea R. Vasconcelos
- Department of Pharmacology, Institute of Biomedical Science, University of São PauloSão Paulo, Brazil
| | - Luis E. M. Quintas
- Laboratory of Biochemical and Molecular Pharmacology, Institute of Biomedical Sciences, Federal University of Rio de JaneiroRio de Janeiro, Brazil
| | - Elisa M. Kawamoto
- Department of Pharmacology, Institute of Biomedical Science, University of São PauloSão Paulo, Brazil
| | - Cristoforo Scavone
- Department of Pharmacology, Institute of Biomedical Science, University of São PauloSão Paulo, Brazil
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47
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Isaksen TJ, Lykke-Hartmann K. Insights into the Pathology of the α2-Na(+)/K(+)-ATPase in Neurological Disorders; Lessons from Animal Models. Front Physiol 2016; 7:161. [PMID: 27199775 PMCID: PMC4854887 DOI: 10.3389/fphys.2016.00161] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2016] [Accepted: 04/15/2016] [Indexed: 12/12/2022] Open
Abstract
A functional Na+/K+-ATPase consists of a catalytic α subunit and a regulatory β subunit. Four α isoforms of the Na+/K+-ATPase are found in mammals, each with a unique expression pattern and catalytic activity. The α2 isoform, encoded by the ATP1A2 gene, is primarily found in the central nervous system (CNS) and in heart-, skeletal- and smooth muscle tissues. In the CNS, the α2 isoform is mainly expressed in glial cells. In particular, the α2 isoform is found in astrocytes, important for astrocytic K+ clearance and, consequently, the indirect uptake of neurotransmitters. Both processes are essential for proper brain activity, and autosomal dominantly mutations in the ATP1A2 gene cause the neurological disorder Familial hemiplegic migraine type 2 (FHM2). FHM2 is a severe subtype of migraine with aura including temporary numbness or weakness, and affecting only one side of the body. FHM2 patients often suffer from neurological comorbidities such as seizures, sensory disturbances, cognitive impairment, and psychiatric manifestations. The functional consequences of FHM2 disease mutations leads to a partial or complete loss of function of pump activity; however, a clear phenotype-genotype correlation has yet to be elucidated. Gene-modified mouse models targeting the Atp1a2 gene have proved instrumental in the understanding of the pathology of FHM2. Several Atp1a2 knockout (KO) mice targeting different exons have been reported. Homozygous Atp1a2 KO mice die shortly after birth due to respiratory malfunction resulting from abnormal Cl− homeostasis in brainstem neurons. Heterozygous KO mice are viable, but display altered behavior and neurological deficits such as altered spatial learning, decreased motor activity and enhanced fear/anxiety compared to wild type mice. FHM2 knock-in (KI) mouse models carrying the human in vivo disease mutations W887R and G301R have also been reported. Both models display altered cortical spreading depression (CSD) and point to deficits in the glutamatergic system as the main underlying mechanism of FHM2.
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Affiliation(s)
- Toke J Isaksen
- Department of Biomedicine, Aarhus UniversityAarhus, Denmark; Centre for Membrane Pumps in Cells and Disease-PUMPKIN, Danish National Research Foundation, Department of Molecular Biology and Genetics, Aarhus UniversityAarhus, Denmark
| | - Karin Lykke-Hartmann
- Department of Biomedicine, Aarhus UniversityAarhus, Denmark; Centre for Membrane Pumps in Cells and Disease-PUMPKIN, Danish National Research Foundation, Department of Molecular Biology and Genetics, Aarhus UniversityAarhus, Denmark; Aarhus Institute of Advanced Studies, Aarhus UniversityAarhus, Denmark
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48
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Larsen BR, Stoica A, MacAulay N. Managing Brain Extracellular K(+) during Neuronal Activity: The Physiological Role of the Na(+)/K(+)-ATPase Subunit Isoforms. Front Physiol 2016; 7:141. [PMID: 27148079 PMCID: PMC4841311 DOI: 10.3389/fphys.2016.00141] [Citation(s) in RCA: 89] [Impact Index Per Article: 11.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2016] [Accepted: 04/04/2016] [Indexed: 11/13/2022] Open
Abstract
During neuronal activity in the brain, extracellular K+ rises and is subsequently removed to prevent a widespread depolarization. One of the key players in regulating extracellular K+ is the Na+/K+-ATPase, although the relative involvement and physiological impact of the different subunit isoform compositions of the Na+/K+-ATPase remain unresolved. The various cell types in the brain serve a certain temporal contribution in the face of network activity; astrocytes respond directly to the immediate release of K+ from neurons, whereas the neurons themselves become the primary K+ absorbers as activity ends. The kinetic characteristics of the catalytic α subunit isoforms of the Na+/K+-ATPase are, partly, determined by the accessory β subunit with which they combine. The isoform combinations expressed by astrocytes and neurons, respectively, appear to be in line with the kinetic characteristics required to fulfill their distinct physiological roles in clearance of K+ from the extracellular space in the face of neuronal activity. Understanding the nature, impact and effects of the various Na+/K+-ATPase isoform combinations in K+ management in the central nervous system might reveal insights into pathological conditions such as epilepsy, migraine, and spreading depolarization following cerebral ischemia. In addition, particular neurological diseases occur as a result of mutations in the α2- (familial hemiplegic migraine type 2) and α3 isoforms (rapid-onset dystonia parkinsonism/alternating hemiplegia of childhood). This review addresses aspects of the Na+/K+-ATPase in the regulation of extracellular K+ in the central nervous system as well as the related pathophysiology. Understanding the physiological setting in non-pathological tissue would provide a better understanding of the pathological events occurring during disease.
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Affiliation(s)
- Brian Roland Larsen
- Department of Neuroscience and Pharmacology, University of Copenhagen Copenhagen, Denmark
| | - Anca Stoica
- Department of Neuroscience and Pharmacology, University of Copenhagen Copenhagen, Denmark
| | - Nanna MacAulay
- Department of Neuroscience and Pharmacology, University of Copenhagen Copenhagen, Denmark
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49
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Bøttger P, Glerup S, Gesslein B, Illarionova NB, Isaksen TJ, Heuck A, Clausen BH, Füchtbauer EM, Gramsbergen JB, Gunnarson E, Aperia A, Lauritzen M, Lambertsen KL, Nissen P, Lykke-Hartmann K. Glutamate-system defects behind psychiatric manifestations in a familial hemiplegic migraine type 2 disease-mutation mouse model. Sci Rep 2016; 6:22047. [PMID: 26911348 PMCID: PMC4766516 DOI: 10.1038/srep22047] [Citation(s) in RCA: 65] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2015] [Accepted: 02/05/2016] [Indexed: 01/12/2023] Open
Abstract
Migraine is a complex brain disorder, and understanding the complexity of this prevalent disease could improve quality of life for millions of people. Familial Hemiplegic Migraine type 2 (FHM2) is a subtype of migraine with aura and co-morbidities like epilepsy/seizures, cognitive impairments and psychiatric manifestations, such as obsessive-compulsive disorder (OCD). FHM2 disease-mutations locate to the ATP1A2 gene encoding the astrocyte-located α2-isoform of the sodium-potassium pump (α2Na+/K+-ATPase). We show that knock-in mice heterozygous for the FHM2-associated G301R-mutation (α2+/G301R) phenocopy several FHM2-relevant disease traits e.g., by mimicking mood depression and OCD. In vitro studies showed impaired glutamate uptake in hippocampal mixed astrocyte-neuron cultures from α2G301R/G301R E17 embryonic mice, and moreover, induction of cortical spreading depression (CSD) resulted in reduced recovery in α2+/G301R male mice. Moreover, NMDA-type glutamate receptor antagonists or progestin-only treatment reverted specific α2+/G301R behavioral phenotypes. Our findings demonstrate that studies of an in vivo relevant FHM2 disease knock-in mouse model provide a link between the female sex hormone cycle and the glutamate system and a link to co-morbid psychiatric manifestations of FHM2.
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Affiliation(s)
- Pernille Bøttger
- Aarhus University, Department of Biomedicine, DK-8000 Aarhus, Denmark.,Centre for Membrane Pumps in Cells and Disease-PUMPKIN, Danish National Research Foundation, Aarhus University, Department of Molecular Biology and Genetics, DK-8000 Aarhus C, Denmark.,University of Southern Denmark, Institute of Molecular Medicine, Department of Neurobiology Research, DK-5000 Odense, Denmark
| | - Simon Glerup
- Aarhus University, Department of Biomedicine, DK-8000 Aarhus, Denmark.,The Lundbeck Foundation Research Centre MIND, Aarhus University, Department of Biomedicine, DK-8000 Aarhus C, Denmark
| | - Bodil Gesslein
- University of Copenhagen, Department of Neuroscience and Pharmacology and Center for Healthy Aging, DK-2200 Copenhagen N, Denmark
| | - Nina B Illarionova
- Karolinska Institutet, Department of Women's and Children's Health, SE-171 76 Stockholm, Sweden
| | - Toke J Isaksen
- Aarhus University, Department of Biomedicine, DK-8000 Aarhus, Denmark.,Centre for Membrane Pumps in Cells and Disease-PUMPKIN, Danish National Research Foundation, Aarhus University, Department of Molecular Biology and Genetics, DK-8000 Aarhus C, Denmark
| | - Anders Heuck
- Aarhus University, Department of Biomedicine, DK-8000 Aarhus, Denmark.,Centre for Membrane Pumps in Cells and Disease-PUMPKIN, Danish National Research Foundation, Aarhus University, Department of Molecular Biology and Genetics, DK-8000 Aarhus C, Denmark
| | - Bettina H Clausen
- University of Southern Denmark, Institute of Molecular Medicine, Department of Neurobiology Research, DK-5000 Odense, Denmark
| | | | - Jan B Gramsbergen
- University of Southern Denmark, Institute of Molecular Medicine, Department of Neurobiology Research, DK-5000 Odense, Denmark
| | - Eli Gunnarson
- Karolinska Institutet, Department of Women's and Children's Health, SE-171 76 Stockholm, Sweden
| | - Anita Aperia
- Karolinska Institutet, Department of Women's and Children's Health, SE-171 76 Stockholm, Sweden
| | - Martin Lauritzen
- University of Copenhagen, Department of Neuroscience and Pharmacology and Center for Healthy Aging, DK-2200 Copenhagen N, Denmark.,Glostrup Hospital, Department of Clinical Neurophysiology, DK-2600 Glostrup, Denmark
| | - Kate L Lambertsen
- University of Southern Denmark, Institute of Molecular Medicine, Department of Neurobiology Research, DK-5000 Odense, Denmark
| | - Poul Nissen
- Centre for Membrane Pumps in Cells and Disease-PUMPKIN, Danish National Research Foundation, Aarhus University, Department of Molecular Biology and Genetics, DK-8000 Aarhus C, Denmark.,Aarhus University, Department of Molecular Biology and Genetics, DK-8000 Aarhus, Denmark.,Danish Research Institute for Translational Neuroscience-DANDRITE, Nordic-EMBL Partnership of Molecular Medicine, Aarhus University, Department of Molecular Biology and Genetics and Department of Biomedicine, DK-8000 Aarhus C, Denmark
| | - Karin Lykke-Hartmann
- Aarhus University, Department of Biomedicine, DK-8000 Aarhus, Denmark.,Centre for Membrane Pumps in Cells and Disease-PUMPKIN, Danish National Research Foundation, Aarhus University, Department of Molecular Biology and Genetics, DK-8000 Aarhus C, Denmark.,Aarhus Institute of Advanced Studies, Aarhus University, Høegh-Guldbergs Gade 6B DK-8000 Aarhus C, Denmark
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50
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Watanabe M, Fukuda A. Development and regulation of chloride homeostasis in the central nervous system. Front Cell Neurosci 2015; 9:371. [PMID: 26441542 PMCID: PMC4585146 DOI: 10.3389/fncel.2015.00371] [Citation(s) in RCA: 141] [Impact Index Per Article: 15.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2015] [Accepted: 09/04/2015] [Indexed: 12/22/2022] Open
Abstract
γ-Aminobutyric acid (GABA) is the main inhibitory neurotransmitter of the mature central nervous system (CNS). The developmental switch of GABAergic transmission from excitation to inhibition is induced by changes in Cl− gradients, which are generated by cation-Cl− co-transporters. An accumulation of Cl− by the Na+-K+-2Cl− co-transporter (NKCC1) increases the intracellular Cl− concentration ([Cl−]i) such that GABA depolarizes neuronal precursors and immature neurons. The subsequent ontogenetic switch, i.e., upregulation of the Cl−-extruder KCC2, which is a neuron-specific K+-Cl− co-transporter, with or without downregulation of NKCC1, results in low [Cl−]i levels and the hyperpolarizing action of GABA in mature neurons. Development of Cl− homeostasis depends on developmental changes in NKCC1 and KCC2 expression. Generally, developmental shifts (decreases) in [Cl−]i parallel the maturation of the nervous system, e.g., early in the spinal cord, hypothalamus and thalamus, followed by the limbic system, and last in the neocortex. There are several regulators of KCC2 and/or NKCC1 expression, including brain-derived neurotrophic factor (BDNF), insulin-like growth factor (IGF), and cystic fibrosis transmembrane conductance regulator (CFTR). Therefore, regionally different expression of these regulators may also contribute to the regional developmental shifts of Cl− homeostasis. KCC2 and NKCC1 functions are also regulated by phosphorylation by enzymes such as PKC, Src-family tyrosine kinases, and WNK1–4 and their downstream effectors STE20/SPS1-related proline/alanine-rich kinase (SPAK)-oxidative stress responsive kinase-1 (OSR1). In addition, activation of these kinases is modulated by humoral factors such as estrogen and taurine. Because these transporters use the electrochemical driving force of Na+ and K+ ions, topographical interaction with the Na+-K+ ATPase and its modulators such as creatine kinase (CK) should modulate functions of Cl− transporters. Therefore, regional developmental regulation of these regulators and modulators of Cl− transporters may also play a pivotal role in the development of Cl− homeostasis.
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Affiliation(s)
- Miho Watanabe
- Department of Neurophysiology, Hamamatsu University School of Medicine Hamamatsu, Japan
| | - Atsuo Fukuda
- Department of Neurophysiology, Hamamatsu University School of Medicine Hamamatsu, Japan
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