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Ygberg S, Akkuratov EE, Howard RJ, Taylan F, Jans DC, Mahato DR, Katz A, Kinoshita PF, Portal B, Nennesmo I, Lindskog M, Karlish SJD, Andersson M, Lindstrand A, Brismar H, Aperia A. A missense mutation converts the Na +,K +-ATPase into an ion channel and causes therapy-resistant epilepsy. J Biol Chem 2021; 297:101355. [PMID: 34717959 PMCID: PMC8637647 DOI: 10.1016/j.jbc.2021.101355] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2021] [Revised: 10/14/2021] [Accepted: 10/25/2021] [Indexed: 11/16/2022] Open
Abstract
The ion pump Na+,K+-ATPase is a critical determinant of neuronal excitability; however, its role in the etiology of diseases of the central nervous system (CNS) is largely unknown. We describe here the molecular phenotype of a Trp931Arg mutation of the Na+,K+-ATPase catalytic α1 subunit in an infant diagnosed with therapy-resistant lethal epilepsy. In addition to the pathological CNS phenotype, we also detected renal wasting of Mg2+. We found that membrane expression of the mutant α1 protein was low, and ion pumping activity was lost. Arginine insertion into membrane proteins can generate water-filled pores in the plasma membrane, and our molecular dynamic (MD) simulations of the principle states of Na+,K+-ATPase transport demonstrated massive water inflow into mutant α1 and destabilization of the ion-binding sites. MD simulations also indicated that a water pathway was created between the mutant arginine residue and the cytoplasm, and analysis of oocytes expressing mutant α1 detected a nonspecific cation current. Finally, neurons expressing mutant α1 were observed to be depolarized compared with neurons expressing wild-type protein, compatible with a lowered threshold for epileptic seizures. The results imply that Na+,K+-ATPase should be considered a neuronal locus minoris resistentia in diseases associated with epilepsy and with loss of plasma membrane integrity.
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Affiliation(s)
- Sofia Ygberg
- Neuropediatric Unit, Department of Women's and Children's Health, Karolinska Institutet, Stockholm, Sweden; Centre for Inherited Metabolic Diseases (CMMS), Karolinska University Hospital, Stockholm, Sweden
| | - Evgeny E Akkuratov
- Science for Life Laboratory, Department of Applied Physics, Royal Institute of Technology, Stockholm, Sweden
| | - Rebecca J Howard
- Science for Life Laboratory, Department of Biochemistry and Biophysics, Stockholm University, Stockholm, Sweden
| | - Fulya Taylan
- Department of Molecular Medicine and Surgery, Center for Molecular Medicine, Karolinska Institutet, Stockholm, Sweden; Department of Neurobiology, Care Sciences and Society, Karolinska Institutet, Stockholm, Sweden
| | - Daniel C Jans
- Science for Life Laboratory, Department of Applied Physics, Royal Institute of Technology, Stockholm, Sweden
| | | | - Adriana Katz
- Department of Biomolecular Sciences, Weizmann Institute of Science, Rehovoth, Israel
| | - Paula F Kinoshita
- Department of Pharmacology, Institute of Biomedical Science, University of São Paulo, São Paulo, Brazil
| | - Benjamin Portal
- Department of Neurobiology, Care Sciences and Society, Karolinska Institutet, Stockholm, Sweden
| | - Inger Nennesmo
- Department of Pathology, Karolinska University Hospital, Stockholm, Sweden
| | - Maria Lindskog
- Department of Neurobiology, Care Sciences and Society, Karolinska Institutet, Stockholm, Sweden
| | - Steven J D Karlish
- Department of Biomolecular Sciences, Weizmann Institute of Science, Rehovoth, Israel
| | | | - Anna Lindstrand
- Department of Molecular Medicine and Surgery, Center for Molecular Medicine, Karolinska Institutet, Stockholm, Sweden; Department of Clinical Genetics, Karolinska University Hospital, Stockholm, Sweden
| | - Hjalmar Brismar
- Science for Life Laboratory, Department of Applied Physics, Royal Institute of Technology, Stockholm, Sweden; Science for Life Laboratory, Department of Women's and Children's Health, Karolinska Institutet, Stockholm, Sweden.
| | - Anita Aperia
- Science for Life Laboratory, Department of Women's and Children's Health, Karolinska Institutet, Stockholm, Sweden
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Bernhem K, Fontana JM, Svensson D, Zhang L, Nilsson LM, Scott L, Blom H, Brismar H, Aperia A. Super-resolution microscopy reveals that Na +/K +-ATPase signaling protects against glucose-induced apoptosis by deactivating Bad. Cell Death Dis 2021; 12:739. [PMID: 34315852 PMCID: PMC8316575 DOI: 10.1038/s41419-021-04025-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2020] [Revised: 07/14/2021] [Accepted: 07/14/2021] [Indexed: 11/08/2022]
Abstract
Activation of the apoptotic pathway is a major cause of progressive loss of function in chronic diseases such as neurodegenerative and diabetic kidney diseases. There is an unmet need for an anti-apoptotic drug that acts in the early stage of the apoptotic process. The multifunctional protein Na+,K+-ATPase has, in addition to its role as a transporter, a signaling function that is activated by its ligand, the cardiotonic steroid ouabain. Several lines of evidence suggest that sub-saturating concentrations of ouabain protect against apoptosis of renal epithelial cells, a common complication and major cause of death in diabetic patients. Here, we induced apoptosis in primary rat renal epithelial cells by exposing them to an elevated glucose concentration (20 mM) and visualized the early steps in the apoptotic process using super-resolution microscopy. Treatment with 10 nM ouabain interfered with the onset of the apoptotic process by inhibiting the activation of the BH3-only protein Bad and its translocation to mitochondria. This occurred before the pro-apoptotic protein Bax had been recruited to mitochondria. Two ouabain regulated and Akt activating Ca2+/calmodulin-dependent kinases were found to play an essential role in the ouabain anti-apoptotic effect. Our results set the stage for further exploration of ouabain as an anti-apoptotic drug in diabetic kidney disease as well as in other chronic diseases associated with excessive apoptosis.
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Affiliation(s)
- Kristoffer Bernhem
- Science for Life Laboratory, Department of Applied Physics, Royal Institute of Technology, Solna, Sweden
| | - Jacopo M Fontana
- Science for Life Laboratory, Department of Applied Physics, Royal Institute of Technology, Solna, Sweden
| | - Daniel Svensson
- Science for Life Laboratory, Department of Women's and Children's Health, Karolinska Institutet, Solna, Sweden
| | - Liang Zhang
- Science for Life Laboratory, Department of Women's and Children's Health, Karolinska Institutet, Solna, Sweden
| | - Linnéa M Nilsson
- Science for Life Laboratory, Department of Applied Physics, Royal Institute of Technology, Solna, Sweden
| | - Lena Scott
- Science for Life Laboratory, Department of Women's and Children's Health, Karolinska Institutet, Solna, Sweden
| | - Hans Blom
- Science for Life Laboratory, Department of Applied Physics, Royal Institute of Technology, Solna, Sweden
| | - Hjalmar Brismar
- Science for Life Laboratory, Department of Applied Physics, Royal Institute of Technology, Solna, Sweden.
- Science for Life Laboratory, Department of Women's and Children's Health, Karolinska Institutet, Solna, Sweden.
| | - Anita Aperia
- Science for Life Laboratory, Department of Women's and Children's Health, Karolinska Institutet, Solna, Sweden
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Akkuratov EE, Westin L, Vazquez-Juarez E, de Marothy M, Melnikova AK, Blom H, Lindskog M, Brismar H, Aperia A. Ouabain Modulates the Functional Interaction Between Na,K-ATPase and NMDA Receptor. Mol Neurobiol 2020; 57:4018-4030. [PMID: 32651756 PMCID: PMC7467916 DOI: 10.1007/s12035-020-01984-5] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2020] [Accepted: 06/08/2020] [Indexed: 12/18/2022]
Abstract
The N-methyl-D-aspartate (NMDA) receptor plays an essential role in glutamatergic transmission and synaptic plasticity and researchers are seeking for different modulators of NMDA receptor function. One possible mechanism for its regulation could be through adjacent membrane proteins. NMDA receptors coprecipitate with Na,K-ATPase, indicating a potential interaction of these two proteins. Ouabain, a mammalian cardiotonic steroid that specifically binds to Na,K-ATPase and affects its conformation, can protect from some toxic effects of NMDA receptor activation. Here we have examined whether NMDA receptor activity and downstream effects can be modulated by physiological ouabain concentrations. The spatial colocalization between NMDA receptors and the Na,K-ATPase catalytic subunits on dendrites of cultured rat hippocampal neurons was analyzed with super-resolution dSTORM microscopy. The functional interaction was analyzed with calcium imaging of single hippocampal neurons exposed to 10 μM NMDA in presence and absence of ouabain and by determination of the ouabain effect on NMDA receptor–dependent long-term potentiation. We show that NMDA receptors and the Na,K-ATPase catalytic subunits alpha1 and alpha3 exist in same protein complex and that ouabain in nanomolar concentration consistently reduces the calcium response to NMDA. Downregulation of the NMDA response is not associated with internalization of the receptor or with alterations in its state of Src phosphorylation. Ouabain in nanomolar concentration elicits a long-term potentiation response. Our findings suggest that ouabain binding to a fraction of Na,K-ATPase molecules that cluster with the NMDA receptors will, via a conformational effect on the NMDA receptors, cause moderate but consistent reduction of NMDA receptor response at synaptic activation.
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Affiliation(s)
- Evgeny E Akkuratov
- Science for Life Laboratory, Department of Applied Physics, Kungliga Tekniska Högskolan, Stockholm, Sweden
| | - Linda Westin
- Science for Life Laboratory, Department of Women's and Children's health, Karolinska Institutet, Stockholm, Sweden
| | - Erika Vazquez-Juarez
- Department of Neurobiology, Care Sciences and Society, Karolinska Institutet, Stockholm, Sweden
| | - Minttu de Marothy
- Science for Life Laboratory, Department of Women's and Children's health, Karolinska Institutet, Stockholm, Sweden
| | - Aleksandra K Melnikova
- Faculty of Bioengineering and Bioinformatics, Lomonosov Moscow State University, Moscow, Russia, 119234
| | - Hans Blom
- Science for Life Laboratory, Department of Applied Physics, Kungliga Tekniska Högskolan, Stockholm, Sweden
| | - Maria Lindskog
- Department of Neurobiology, Care Sciences and Society, Karolinska Institutet, Stockholm, Sweden
| | - Hjalmar Brismar
- Science for Life Laboratory, Department of Applied Physics, Kungliga Tekniska Högskolan, Stockholm, Sweden.
| | - Anita Aperia
- Science for Life Laboratory, Department of Women's and Children's health, Karolinska Institutet, Stockholm, Sweden
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Aperia A, Brismar H, Uhlén P. Mending Fences: Na,K-ATPase signaling via Ca 2+ in the maintenance of epithelium integrity. Cell Calcium 2020; 88:102210. [PMID: 32380435 DOI: 10.1016/j.ceca.2020.102210] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2020] [Revised: 04/20/2020] [Accepted: 04/21/2020] [Indexed: 12/18/2022]
Abstract
Na,K-ATPase is a ubiquitous multifunctional protein that acts both as an ion pump and as a signal transducer. The signaling function is activated by ouabain in non-toxic concentrations. In epithelial cells the ouabain-bound Na,K-ATPase connects with the inositol 1,4,5-trisphosphate receptor via a short linear motif to activate low frequency Ca2+ oscillations. Within a couple of minutes this ouabain mediated signal has resulted in phosphorylation or dephosphorylation of 2580 phospho-sites. Proteins that control cell proliferation and cell adhesion and calmodulin regulated proteins are enriched among the ouabain phosphor-regulated proteins. The inositol 1,4,5-trisphosphate receptor and the stromal interaction molecule, which are both essential for the initiation of Ca2+ oscillations, belong to the ouabain phosphor-regulated proteins. Downstream effects of the ouabain-evoked Ca2+ signal in epithelial cells include interference with the intrinsic mitochondrial apoptotic process and stimulation of embryonic growth processes. The dual function of Na,K-ATPase as an ion pump and a signal transducer is now well established and evaluation of the physiological and pathophysiological consequences of this universal signal emerges as an urgent topic for future studies.
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Affiliation(s)
- Anita Aperia
- Science for Life Laboratory, Dept of Women's and Children's Health, Karolinska Institutet, Sweden
| | - Hjalmar Brismar
- Science for Life Laboratory, Dept of Women's and Children's Health, Karolinska Institutet, Sweden; Science for Life Laboratory, Dept of Applied Physics, KTH Royal Institute of Technology, Sweden.
| | - Per Uhlén
- Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Sweden
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5
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Howard R, Ygberg S, Andersson M, Akkuratov E, Jans D, Brismar H, Lindstrand A, Aperia A. Defective membrane insertion of mutant Na,K‐ATPase, a cause of fatal epilepsy. FASEB J 2020. [DOI: 10.1096/fasebj.2020.34.s1.05054] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
| | | | | | | | - Daniel Jans
- Royal Institute of Technology Science for Life Laboratory
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6
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Panizza E, Zhang L, Fontana JM, Hamada K, Svensson D, Akkuratov EE, Scott L, Mikoshiba K, Brismar H, Lehtiö J, Aperia A. Ouabain-regulated phosphoproteome reveals molecular mechanisms for Na +, K +-ATPase control of cell adhesion, proliferation, and survival. FASEB J 2019; 33:10193-10206. [PMID: 31199885 PMCID: PMC6704450 DOI: 10.1096/fj.201900445r] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
The ion pump Na+, K+-ATPase (NKA) is a receptor for the cardiotonic steroid ouabain. Subsaturating concentration of ouabain triggers intracellular calcium oscillations, stimulates cell proliferation and adhesion, and protects from apoptosis. However, it is controversial whether ouabain-bound NKA is considered a signal transducer. To address this question, we performed a global analysis of protein phosphorylation in COS-7 cells, identifying 2580 regulated phosphorylation events on 1242 proteins upon 10- and 20-min treatment with ouabain. Regulated phosphorylated proteins include the inositol triphosphate receptor and stromal interaction molecule, which are essential for initiating calcium oscillations. Hierarchical clustering revealed that ouabain triggers a structured phosphorylation response that occurs in a well-defined, time-dependent manner and affects specific cellular processes, including cell proliferation and cell-cell junctions. We additionally identify regulation of the phosphorylation of several calcium and calmodulin-dependent protein kinases (CAMKs), including 2 sites of CAMK type II-γ (CAMK2G), a protein known to regulate apoptosis. To verify the significance of this result, CAMK2G was knocked down in primary kidney cells. CAMK2G knockdown impaired ouabain-dependent protection from apoptosis upon treatment with high glucose or serum deprivation. In conclusion, we establish NKA as the coordinator of a broad, tightly regulated phosphorylation response in cells and define CAMK2G as a downstream effector of NKA.-Panizza, E., Zhang, L., Fontana, J. M., Hamada, K., Svensson, D., Akkuratov, E. E., Scott, L., Mikoshiba, K., Brismar, H., Lehtiö, J., Aperia, A. Ouabain-regulated phosphoproteome reveals molecular mechanisms for Na+, K+-ATPase control of cell adhesion, proliferation, and survival.
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Affiliation(s)
- Elena Panizza
- Department of Oncology-Pathology, Science for Life Laboratory, Karolinska Institutet, Solna, Sweden
| | - Liang Zhang
- Department of Women's and Children's Health, Karolinska Institutet, Solna, Sweden
| | - Jacopo Maria Fontana
- Department of Applied Physics, Science for Life Laboratory, Royal Institute of Technology, Stockholm, Sweden
| | - Kozo Hamada
- Laboratory for Developmental Neurobiology, Brain Science Institute, Riken, Saitama, Japan
| | - Daniel Svensson
- Department of Women's and Children's Health, Karolinska Institutet, Solna, Sweden
| | - Evgeny E Akkuratov
- Department of Applied Physics, Science for Life Laboratory, Royal Institute of Technology, Stockholm, Sweden
| | - Lena Scott
- Department of Women's and Children's Health, Karolinska Institutet, Solna, Sweden
| | - Katsuhiko Mikoshiba
- Laboratory for Developmental Neurobiology, Brain Science Institute, Riken, Saitama, Japan
| | - Hjalmar Brismar
- Department of Women's and Children's Health, Karolinska Institutet, Solna, Sweden.,Department of Applied Physics, Science for Life Laboratory, Royal Institute of Technology, Stockholm, Sweden
| | - Janne Lehtiö
- Department of Oncology-Pathology, Science for Life Laboratory, Karolinska Institutet, Solna, Sweden
| | - Anita Aperia
- Department of Women's and Children's Health, Karolinska Institutet, Solna, Sweden
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7
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Panizza E, Svensson D, Zhang L, Fontana JM, Akkuratov E, Scott L, Brismar H, Lehtiö J, Aperia A. Ouabain Regulated Phosphoproteome Reveals Molecular Mechanisms Behind Na, K‐ATPase Control of Cell Adhesion, Proliferation and Survival. FASEB J 2019. [DOI: 10.1096/fasebj.2019.33.1_supplement.476.21] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
| | | | | | | | | | | | - Hjalmar Brismar
- Karolinska InstitutetSolnaSweden
- Royal Institute of TechnologySolnaSweden
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Svensson D, Zhang L, Panizza E, Nilsson L, Fontana JM, Moruzzi N, Scott L, Brismar H, Aperia A. A Novel Concept for Origin and Treatment of Diabetic Nephropathy. FASEB J 2019. [DOI: 10.1096/fasebj.2019.33.1_supplement.567.4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
| | | | - Elena Panizza
- Department of Molecular MedicineCornell UniversityIthacaNY
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Nilsson LM, Zhang L, Bondar A, Svensson D, Wernerson A, Brismar H, Scott L, Aperia A. Prompt apoptotic response to high glucose in SGLT-expressing renal cells. Am J Physiol Renal Physiol 2019; 316:F1078-F1089. [PMID: 30864838 PMCID: PMC6580252 DOI: 10.1152/ajprenal.00615.2018] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
It is generally believed that cells that are unable to downregulate glucose transport are particularly vulnerable to hyperglycemia. Yet, little is known about the relation between expression of glucose transporters and acute toxic effects of high glucose exposure. In the present ex vivo study of rat renal cells, we compared the apoptotic response to a moderate increase in glucose concentration. We studied cell types that commonly are targeted in diabetic kidney disease (DKD): proximal tubule cells, which express Na+-dependent glucose transporter (SGLT)2, mesangial cells, which express SGLT1, and podocytes, which lack SGLT and take up glucose via insulin-dependent glucose transporter 4. Proximal tubule cells and mesangial cells responded within 4–8 h of exposure to 15 mM glucose with translocation of the apoptotic protein Bax to mitochondria and an increased apoptotic index. SGLT downregulation and exposure to SGLT inhibitors abolished the apoptotic response. The onset of overt DKD generally coincides with the onset of albuminuria. Albumin had an additive effect on the apoptotic response. Ouabain, which interferes with the apoptotic onset, rescued from the apoptotic response. Insulin-supplemented podocytes remained resistant to 15 and 30 mM glucose for at least 24 h. Our study points to a previously unappreciated role of SGLT-dependent glucose uptake as a risk factor for diabetic complications and highlights the importance of therapeutic approaches that specifically target the different cell types in DKD.
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Affiliation(s)
- Linnéa M Nilsson
- Science for Life Laboratory, Department of Applied Physics, Royal Institute of Technology, Solna, Sweden
| | - Liang Zhang
- Science for Life Laboratory, Department of Women's and Children's Health, Karolinska Institutet, Solna, Sweden
| | - Alexander Bondar
- Institute of Chemical Biology and Fundamental Medicine, Novosibirisk, Russia
| | - Daniel Svensson
- Science for Life Laboratory, Department of Women's and Children's Health, Karolinska Institutet, Solna, Sweden
| | - Annika Wernerson
- Division of Renal Medicine, Department of Clinical Science, Intervention and Technology, Karolinska Institutet , Stockholm , Sweden
| | - Hjalmar Brismar
- Science for Life Laboratory, Department of Applied Physics, Royal Institute of Technology, Solna, Sweden.,Science for Life Laboratory, Department of Women's and Children's Health, Karolinska Institutet, Solna, Sweden
| | - Lena Scott
- Science for Life Laboratory, Department of Women's and Children's Health, Karolinska Institutet, Solna, Sweden
| | - Anita Aperia
- Science for Life Laboratory, Department of Women's and Children's Health, Karolinska Institutet, Solna, Sweden
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Fontana JM, Khodus GR, Unnersjö-Jess D, Blom H, Aperia A, Brismar H. Spontaneous calcium activity in metanephric mesenchymal cells regulates branching morphogenesis in the embryonic kidney. FASEB J 2018; 33:4089-4096. [PMID: 30496703 PMCID: PMC6404591 DOI: 10.1096/fj.201802054r] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
The central role of calcium signaling during development of early vertebrates is well documented, but little is known about its role in mammalian embryogenesis. We have used immunofluorescence and time-lapse calcium imaging of cultured explanted embryonic rat kidneys to study the role of calcium signaling for branching morphogenesis. In mesenchymal cells, we recorded spontaneous calcium activity that was characterized by irregular calcium transients. The calcium signals were dependent on release of calcium from intracellular stores in the endoplasmic reticulum. Down-regulation of the calcium activity, both by blocking the sarco-endoplasmic reticulum Ca2+-ATPase and by chelating cytosolic calcium, resulted in retardation of branching morphogenesis and a reduced formation of primitive nephrons but had no effect on cell proliferation. We propose that spontaneous calcium activity contributes with a stochastic factor to the self-organizing process that controls branching morphogenesis, a major determinant of the ultimate number of nephrons in the kidney.-Fontana, J. M., Khodus, G. R., Unnersjö-Jess, D., Blom, H., Aperia, A., Brismar, H. Spontaneous calcium activity in metanephric mesenchymal cells regulates branching morphogenesis in the embryonic kidney.
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Affiliation(s)
- Jacopo M Fontana
- Department of Applied Physics, Science for Life Laboratory, Kungliga Tekniska Högskolan (KTH) Royal Institute of Technology, Solna, Sweden
| | - Georgiy R Khodus
- Department of Applied Physics, Science for Life Laboratory, Kungliga Tekniska Högskolan (KTH) Royal Institute of Technology, Solna, Sweden
| | - David Unnersjö-Jess
- Department of Applied Physics, Science for Life Laboratory, Kungliga Tekniska Högskolan (KTH) Royal Institute of Technology, Solna, Sweden
| | - Hans Blom
- Department of Applied Physics, Science for Life Laboratory, Kungliga Tekniska Högskolan (KTH) Royal Institute of Technology, Solna, Sweden
| | - Anita Aperia
- Department of Women's and Children's Health, Science for Life Laboratory, Karolinska Institutet, Solna, Sweden
| | - Hjalmar Brismar
- Department of Applied Physics, Science for Life Laboratory, Kungliga Tekniska Högskolan (KTH) Royal Institute of Technology, Solna, Sweden.,Department of Women's and Children's Health, Science for Life Laboratory, Karolinska Institutet, Solna, Sweden
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Shrivastava AN, Aperia A, Melki R, Triller A. Physico-Pathologic Mechanisms Involved in Neurodegeneration: Misfolded Protein-Plasma Membrane Interactions. Neuron 2017; 95:33-50. [DOI: 10.1016/j.neuron.2017.05.026] [Citation(s) in RCA: 72] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2016] [Revised: 05/12/2017] [Accepted: 05/19/2017] [Indexed: 12/12/2022]
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Bernhem K, Krishnan K, Bondar A, Brismar H, Aperia A, Scott L. AT 1-receptor response to non-saturating Ang-II concentrations is amplified by calcium channel blockers. BMC Cardiovasc Disord 2017; 17:126. [PMID: 28514967 PMCID: PMC5436436 DOI: 10.1186/s12872-017-0562-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2016] [Accepted: 05/09/2017] [Indexed: 01/13/2023] Open
Abstract
BACKGROUND Blockers of angiotensin II type 1 receptor (AT1R) and the voltage gated calcium channel 1.2 (CaV1.2) are commonly used for treatment of hypertension. Yet there is little information about the effect of physiological concentrations of angiotensin II (AngII) on AT1R signaling and whether there is a reciprocal regulation of AT1R signaling by CaV1.2. METHODS To elucidate these questions, we have studied the Ca2+ signaling response to physiological and pharmacological AngII doses in HEK293a cells, vascular smooth muscle cells and cardiomyocytes using a Ca2+ sensitive dye as the principal sensor. Intra-cellular calcium recordings were performed in presence and absence of CaV1.2 blockers. Semi-quantitative imaging methods were used to assess the plasma membrane expression of AT1R and G-protein activation. RESULTS Repeated exposure to pharmacological (100 nM) concentrations of AngII caused, as expected, a down-regulation of the Ca2+ response. In contrast, repeated exposure to physiological (1 nM) AngII concentration resulted in an enhancement of the Ca2+ response. The up-regulation of the Ca2+ response to repeated 1 nM AngII doses and the down-regulation of the Ca2+ response to repeated 100 nM Angll doses were not accompanied by a parallel change of the AT1R plasma membrane expression. The Ca2+ response to 1 nM of AngII was amplified in the presence of therapeutic concentrations of the CaV1.2 blockers, nifedipine and verapamil, in vascular smooth muscle cells, cardiomyocytes and HEK293a cells. Amplification of the AT1R response was also observed following inhibition of the calcium permeable transient receptor potential cation channels, suggesting that the activity of AT1R is sensitive to calcium influx. CONCLUSIONS Our findings have implications for the understanding of hyperactivity of the angiotensin system and for use of Ca2+ channel blockers as mono-therapy in hypertension.
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Affiliation(s)
- Kristoffer Bernhem
- Science for Life Laboratory, Department of Applied Physics, Royal Institute of Technology, Stockholm, Sweden
| | - Kalaiselvan Krishnan
- Science for Life Laboratory, Department of Applied Physics, Royal Institute of Technology, Stockholm, Sweden
| | - Alexander Bondar
- Institute of Chemical Biology and Fundamental Medicine, 630090, Novosibirsk, Russia
| | - Hjalmar Brismar
- Science for Life Laboratory, Department of Women's and Children's Health, Karolinska Institutet, PO Box 1031, 17121, Solna, Sweden.,Science for Life Laboratory, Department of Applied Physics, Royal Institute of Technology, Stockholm, Sweden
| | - Anita Aperia
- Science for Life Laboratory, Department of Women's and Children's Health, Karolinska Institutet, PO Box 1031, 17121, Solna, Sweden.
| | - Lena Scott
- Science for Life Laboratory, Department of Women's and Children's Health, Karolinska Institutet, PO Box 1031, 17121, Solna, Sweden
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14
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Hannerz L, Wikstad I, Celsi G, Aperia A. Influence of Vesicoureteral Reflux and Urinary Tract Infection on Renal Growth in Children with Upper Urinary Tract Duplication. Acta Radiol 2016. [DOI: 10.1177/028418518903000412] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
The growth of the renal parenchyma was examined in children with duplicated outflow systems, vesicoureteral reflux (VUR), urinary tract infection (UTI) and no sign of obstruction. Ten patients with reflux occurring only in the caudal system (group A) and 4 patients with reflux both to the caudal and the apical system (group B) were studied shortly after their first UTI (study 1) and then 1.5 to 9 years later (study 2). The frequency of UTI was relatively high during the follow-up period. At urography, renal length and renal area were normal in group A in studies 1 and 2. Parenchymal thickness of the apical pole (APT/L) did not differ from normal values in any of the studies. Parenchymal thickness of the caudal pole (CPT/L) was significantly smaller than normal in both studies. There was also a significant decrease in CPT/L between study 1 and 2. UTI during the first year of life was associated with a greater reduction in CPT/L. The determination of renal length and renal area in children with a duplicated ureter, VUR and UTI, does not identify subjects at risk of developing renal growth retardation while serial determinations of parenchymal thickness appear to be an appropriate method.
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15
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Hannerz L, Wikstad I, Johansson L, Broberger O, Aperia A. Distribution of Renal Scars and Intrarenal Reflux in Children with a Past History of Urinary Tract Infection. Acta Radiol 2016. [DOI: 10.1177/028418518702800414] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The distribution of renal scars in children with vesicoureteral reflux (VUR) and a past history of urinary tract infection was studied to see whether a correlation existed between renal scarring and intrarenal reflux. In 37 children with one or more scars in one or both kidneys, scarring was significantly more frequent in the polar areas than in the lateral area. In 7 children with intrarenal reflux (IRR), the distribution of IRR was almost identical with that of renal scarring. When children with marked VUR (grade IV-V) were analyzed separately, a uniform distribution of scars was found. It was concluded that fused papillae, which normally are most frequent in the polar area, are a prerequisite for the development of IRR/renal scars.
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Burlaka I, Nilsson LM, Scott L, Holtbäck U, Eklöf AC, Fogo AB, Brismar H, Aperia A. Prevention of apoptosis averts glomerular tubular disconnection and podocyte loss in proteinuric kidney disease. Kidney Int 2016; 90:135-48. [PMID: 27217195 PMCID: PMC6101029 DOI: 10.1016/j.kint.2016.03.026] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2015] [Revised: 02/19/2016] [Accepted: 03/10/2016] [Indexed: 01/09/2023]
Abstract
There is a great need for treatment that arrests progression of chronic kidney disease. Increased albumin in urine leads to apoptosis and fibrosis of podocytes and tubular cells and is a major cause of functional deterioration. There have been many attempts to target fibrosis, but because of the lack of appropriate agents, few have targeted apoptosis. Our group has described an ouabain-activated Na,K-ATPase/IP3R signalosome, which protects from apoptosis. Here we show that albumin uptake in primary rat renal epithelial cells is accompanied by a time- and dose-dependent mitochondrial accumulation of the apoptotic factor Bax, down-regulation of the antiapoptotic factor Bcl-xL and mitochondrial membrane depolarization. Ouabain opposes these effects and protects from apoptosis in albumin-exposed proximal tubule cells and podocytes. The efficacy of ouabain as an antiapoptotic and kidney-protective therapeutic tool was then tested in rats with passive Heymann nephritis, a model of proteinuric chronic kidney disease. Chronic ouabain treatment preserved renal function, protected from renal cortical apoptosis, up-regulated Bax, down-regulated Bcl-xL, and rescued from glomerular tubular disconnection and podocyte loss. Thus we have identified a novel clinically feasible therapeutic tool, which has the potential to protect from apoptosis and rescue from loss of functional tissue in chronic proteinuric kidney disease.
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Affiliation(s)
- Ievgeniia Burlaka
- Science for Life Laboratory, Department of Women's and Children's Health, Karolinska Institutet, Solna, Sweden
| | - Linnéa M Nilsson
- Science for Life Laboratory, Department of Applied Physics, Royal Institute of Technology, Solna, Sweden
| | - Lena Scott
- Science for Life Laboratory, Department of Women's and Children's Health, Karolinska Institutet, Solna, Sweden.
| | - Ulla Holtbäck
- Science for Life Laboratory, Department of Women's and Children's Health, Karolinska Institutet, Solna, Sweden
| | - Ann-Christine Eklöf
- Science for Life Laboratory, Department of Women's and Children's Health, Karolinska Institutet, Solna, Sweden
| | - Agnes B Fogo
- Department of Pathology, Microbiology and Immunology, Vanderbilt University Medical Center, Nashville, Tennessee, USA
| | - Hjalmar Brismar
- Science for Life Laboratory, Department of Women's and Children's Health, Karolinska Institutet, Solna, Sweden; Science for Life Laboratory, Department of Applied Physics, Royal Institute of Technology, Solna, Sweden
| | - Anita Aperia
- Science for Life Laboratory, Department of Women's and Children's Health, Karolinska Institutet, Solna, Sweden.
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17
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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: 63] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [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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Shrivastava AN, Redeker V, Fritz N, Pieri L, Almeida LG, Spolidoro M, Liebmann T, Bousset L, Renner M, Léna C, Aperia A, Melki R, Triller A. Data in support of the identification of neuronal and astrocyte proteins interacting with extracellularly applied oligomeric and fibrillar α-synuclein assemblies by mass spectrometry. Data Brief 2016; 7:221-8. [PMID: 26958642 PMCID: PMC4773484 DOI: 10.1016/j.dib.2016.02.018] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2015] [Revised: 12/08/2015] [Accepted: 02/04/2016] [Indexed: 12/17/2022] Open
Abstract
α-Synuclein (α-syn) is the principal component of Lewy bodies, the pathophysiological hallmark of individuals affected by Parkinson disease (PD). This neuropathologic form of α-syn contributes to PD progression and propagation of α-syn assemblies between neurons. The data we present here support the proteomic analysis used to identify neuronal proteins that specifically interact with extracellularly applied oligomeric or fibrillar α-syn assemblies (conditions 1 and 2, respectively) (doi: 10.15252/embj.201591397[1]). α-syn assemblies and their cellular partner proteins were pulled down from neuronal cell lysed shortly after exposure to exogenous α-syn assemblies and the associated proteins were identified by mass spectrometry using a shotgun proteomic-based approach. We also performed experiments on pure cultures of astrocytes to identify astrocyte-specific proteins interacting with oligomeric or fibrillar α-syn (conditions 3 and 4, respectively). For each condition, proteins interacting selectively with α-syn assemblies were identified by comparison to proteins pulled-down from untreated cells used as controls. The mass spectrometry data, the database search and the peak lists have been deposited to the ProteomeXchange Consortium database via the PRIDE partner repository with the dataset identifiers PRIDE: PXD002256 to PRIDE: PXD002263 and doi: 10.6019/PXD002256 to 10.6019/PXD002263.
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Affiliation(s)
- Amulya Nidhi Shrivastava
- École Normale Supérieure, Institut de Biologie de l’ENS (IBENS), INSERM, CNRS, PSL Research University, 46 Rue d׳Ulm, Paris 75005, France
| | - Virginie Redeker
- Paris-Saclay Institute of Neuroscience, CNRS, Gif-sur-Yvette 91198, France
- Corresponding author.
| | - Nicolas Fritz
- Department of Women and Children׳s Health, Karolinska Institutet, 171 76 Stockholm, Sweden
| | - Laura Pieri
- Paris-Saclay Institute of Neuroscience, CNRS, Gif-sur-Yvette 91198, France
| | - Leandro G. Almeida
- École Normale Supérieure, Institut de Biologie de l’ENS (IBENS), INSERM, CNRS, PSL Research University, 46 Rue d׳Ulm, Paris 75005, France
| | - Maria Spolidoro
- École Normale Supérieure, Institut de Biologie de l’ENS (IBENS), INSERM, CNRS, PSL Research University, 46 Rue d׳Ulm, Paris 75005, France
| | - Thomas Liebmann
- Department of Women and Children׳s Health, Karolinska Institutet, 171 76 Stockholm, Sweden
| | - Luc Bousset
- Paris-Saclay Institute of Neuroscience, CNRS, Gif-sur-Yvette 91198, France
| | - Marianne Renner
- École Normale Supérieure, Institut de Biologie de l’ENS (IBENS), INSERM, CNRS, PSL Research University, 46 Rue d׳Ulm, Paris 75005, France
| | - Clément Léna
- École Normale Supérieure, Institut de Biologie de l’ENS (IBENS), INSERM, CNRS, PSL Research University, 46 Rue d׳Ulm, Paris 75005, France
| | - Anita Aperia
- Department of Women and Children׳s Health, Karolinska Institutet, 171 76 Stockholm, Sweden
| | - Ronald Melki
- Paris-Saclay Institute of Neuroscience, CNRS, Gif-sur-Yvette 91198, France
| | - Antoine Triller
- École Normale Supérieure, Institut de Biologie de l’ENS (IBENS), INSERM, CNRS, PSL Research University, 46 Rue d׳Ulm, Paris 75005, France
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Abstract
The Na(+)-K(+)-ATPase (NKA) differs from most other ion transporters, not only in its capacity to maintain a steep electrochemical gradient across the plasma membrane, but also as a receptor for a family of cardiotonic steroids, to which ouabain belongs. Studies from many groups, performed during the last 15 years, have demonstrated that ouabain, a member of the cardiotonic steroid family, can activate a network of signaling molecules, and that NKA will also serve as a signal transducer that can provide a feedback loop between NKA and the mitochondria. This brief review summarizes the current knowledge and controversies with regard to the understanding of NKA signaling.
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Affiliation(s)
- Anita Aperia
- Science for Life Laboratory, Department of Women and Children's Health, Karolinska Institutet, Stockholm, Sweden; and
| | - Evgeny E Akkuratov
- Science for Life Laboratory, Department of Women and Children's Health, Karolinska Institutet, Stockholm, Sweden; and
| | - Jacopo Maria Fontana
- Science for Life Laboratory, Department of Applied Physics, Royal Institute of Technology, Stockholm, Sweden
| | - Hjalmar Brismar
- Science for Life Laboratory, Department of Women and Children's Health, Karolinska Institutet, Stockholm, Sweden; and Science for Life Laboratory, Department of Applied Physics, Royal Institute of Technology, Stockholm, Sweden
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20
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Shrivastava AN, Redeker V, Fritz N, Pieri L, Almeida LG, Spolidoro M, Liebmann T, Bousset L, Renner M, Léna C, Aperia A, Melki R, Triller A. α-synuclein assemblies sequester neuronal α3-Na+/K+-ATPase and impair Na+ gradient. EMBO J 2015; 34:2408-23. [PMID: 26323479 DOI: 10.15252/embj.201591397] [Citation(s) in RCA: 152] [Impact Index Per Article: 16.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2015] [Accepted: 07/21/2015] [Indexed: 11/09/2022] Open
Abstract
Extracellular α-synuclein (α-syn) assemblies can be up-taken by neurons; however, their interaction with the plasma membrane and proteins has not been studied specifically. Here we demonstrate that α-syn assemblies form clusters within the plasma membrane of neurons. Using a proteomic-based approach, we identify the α3-subunit of Na+/K+-ATPase (NKA) as a cell surface partner of α-syn assemblies. The interaction strength depended on the state of α-syn, fibrils being the strongest, oligomers weak, and monomers none. Mutations within the neuron-specific α3-subunit are linked to rapid-onset dystonia Parkinsonism (RDP) and alternating hemiplegia of childhood (AHC). We show that freely diffusing α3-NKA are trapped within α-syn clusters resulting in α3-NKA redistribution and formation of larger nanoclusters. This creates regions within the plasma membrane with reduced local densities of α3-NKA, thereby decreasing the efficiency of Na+ extrusion following stimulus. Thus, interactions of α3-NKA with extracellular α-syn assemblies reduce its pumping activity as its mutations in RDP/AHC.
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Affiliation(s)
- Amulya Nidhi Shrivastava
- École Normale Supérieure, Institut de Biologie de l'ENS (IBENS) INSERM CNRS PSL Research University, Paris, France
| | - Virginie Redeker
- Paris-Saclay Institute of Neuroscience CNRS, Gif-sur-Yvette, France
| | - Nicolas Fritz
- Department of Women and Children's Health, Karolinska Institutet, Stockholm, Sweden
| | - Laura Pieri
- Paris-Saclay Institute of Neuroscience CNRS, Gif-sur-Yvette, France
| | - Leandro G Almeida
- École Normale Supérieure, Institut de Biologie de l'ENS (IBENS) INSERM CNRS PSL Research University, Paris, France
| | - Maria Spolidoro
- École Normale Supérieure, Institut de Biologie de l'ENS (IBENS) INSERM CNRS PSL Research University, Paris, France
| | - Thomas Liebmann
- Department of Women and Children's Health, Karolinska Institutet, Stockholm, Sweden
| | - Luc Bousset
- Paris-Saclay Institute of Neuroscience CNRS, Gif-sur-Yvette, France
| | - Marianne Renner
- École Normale Supérieure, Institut de Biologie de l'ENS (IBENS) INSERM CNRS PSL Research University, Paris, France
| | - Clément Léna
- École Normale Supérieure, Institut de Biologie de l'ENS (IBENS) INSERM CNRS PSL Research University, Paris, France
| | - Anita Aperia
- Department of Women and Children's Health, Karolinska Institutet, Stockholm, Sweden
| | - Ronald Melki
- Paris-Saclay Institute of Neuroscience CNRS, Gif-sur-Yvette, France
| | - Antoine Triller
- École Normale Supérieure, Institut de Biologie de l'ENS (IBENS) INSERM CNRS PSL Research University, Paris, France
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O‐Uchi J, Hurst S, Fontana J, Mishra J, Xu X, Fu D, Jhun BS, Aperia A, Sheu S. Pyk2‐Dependent
Phosphorylation of Mitochondrial Ca
2+
Uniporter
Modulates
Mitochondrial Ca
2+
Uptake
. FASEB J 2015. [DOI: 10.1096/fasebj.29.1_supplement.844.11] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Jin O‐Uchi
- Center for Translational medicineDepartment of medicine Thomas Jefferson UniversityPhiladelphiaPAUnited States
| | - Stephen Hurst
- Center for Translational medicineDepartment of medicine Thomas Jefferson UniversityPhiladelphiaPAUnited States
| | - Jacopo Fontana
- Department of Women's and Children's Health Karolinska InstitutetStockholmSweden
| | - Jyotsna Mishra
- Center for Translational medicineDepartment of medicine Thomas Jefferson UniversityPhiladelphiaPAUnited States
| | - Xiaole Xu
- Center for Translational medicineDepartment of medicine Thomas Jefferson UniversityPhiladelphiaPAUnited States
| | - Deming Fu
- Center for Translational medicineDepartment of medicine Thomas Jefferson UniversityPhiladelphiaPAUnited States
| | - Bong Sook Jhun
- Center for Translational medicineDepartment of medicine Thomas Jefferson UniversityPhiladelphiaPAUnited States
| | - Anita Aperia
- Department of Women's and Children's Health Karolinska InstitutetStockholmSweden
| | - Shey‐Shing Sheu
- Center for Translational medicineDepartment of medicine Thomas Jefferson UniversityPhiladelphiaPAUnited States
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Fritz N, Akkuratov E, Liebmann T, Lindskog M, Brismar H, Aperia A. Functional consequences of the disease‐causing T613M mutation of NKAalpha3 for hippocampal neurons. FASEB J 2015. [DOI: 10.1096/fasebj.29.1_supplement.845.29] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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23
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Fontana J, Fritz N, Brismar H, Aperia A. Apoptosis caused by excessive mitochondrial albumin uptake in renal cells is initiated by increased mitochondrial calcium concentration. FASEB J 2015. [DOI: 10.1096/fasebj.29.1_supplement.845.30] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Uematsu K, Heiman M, Zelenina M, Padovan J, Chait BT, Aperia A, Nishi A, Greengard P. Protein kinase A directly phosphorylates metabotropic glutamate receptor 5 to modulate its function. J Neurochem 2015; 132:677-86. [PMID: 25639954 DOI: 10.1111/jnc.13038] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2014] [Revised: 12/14/2014] [Accepted: 01/14/2015] [Indexed: 11/30/2022]
Abstract
Metabotropic glutamate receptor 5 (mGluR5) regulates excitatory post-synaptic signaling in the central nervous system (CNS) and is implicated in various CNS disorders. Protein kinase A (PKA) signaling is known to play a critical role in neuropsychiatric disorders such as Parkinson's disease, schizophrenia, and addiction. Dopamine signaling is known to modulate the properties of mGluR5 in a cAMP- and PKA-dependent manner, suggesting that mGluR5 may be a direct target for PKA. Our study identifies mGluR5 at Ser870 as a direct substrate for PKA phosphorylation and demonstrates that this phosphorylation plays a critical role in the PKA-mediated modulation of mGluR5 functions such as extracellular signal-regulated kinase phosphorylation and intracellular Ca(2+) oscillations. The identification of the molecular mechanism by which PKA signaling modulates mGluR5-mediated cellular responses contributes to the understanding of the interaction between dopaminergic and glutamatergic neuronal signaling. We identified serine residue 870 (S870) in metabotropic glutamate receptor 5 (mGluR5) as a direct substrate for protein kinase A (PKA). The phosphorylation of this site regulates the ability of mGluR5 to induce extracellular signal-regulated kinase (ERK) phosphorylation and intracellular Ca(2+) oscillations. This study provides a direct molecular mechanism by which PKA signaling interacts with glutamate neurotransmission.
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Affiliation(s)
- Ken Uematsu
- Laboratory of Molecular and Cellular Neuroscience, The Rockefeller University, New York, New York, USA; Department of Pharmacology, Kurume University School of Medicine, Kurume, Fukuoka, Japan; Department of Psychiatry, Kurume University School of Medicine, Kurume, Fukuoka, Japan; Cognitive and Molecular Research Institute of Brain Diseases, Kurume University, Kurume, Fukuoka, Japan
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25
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Brismar H, Aperia A, Westin L, Moy J, Wang M, Guillermier C, Poczatek C, Lechene C. Study of protein and RNA in dendritic spines using multi-isotope imaging mass spectrometry (MIMS). SURF INTERFACE ANAL 2014; 46:158-160. [PMID: 26379339 PMCID: PMC4566155 DOI: 10.1002/sia.5617] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
The classical view of neuronal protein synthesis is that proteins are made in the cell body and then transported to their functional sites in the dendrites and the dendritic spines. Indirect evidence, however, suggests that protein synthesis can directly occur in the distal dendrites, far from the cell body. We are developing protocols for dual labeling of RNA and proteins using 15N-uridine and 18O- or 13C-leucine pulse chase in cultured neurons to identify and localize both protein synthesis and fate of newly synthesized proteins. Pilot experiments show discrete localization of both RNA and newly synthesized proteins in dendrites, close to dendritic spines. We have for the first time directly imaged and measured the production of proteins at the subcellular level in the neuronal dendrites, close to the functional sites, the dendritic spines. This will open a powerful way to study neural growth and synapse plasticity in health and disease.
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Affiliation(s)
- H Brismar
- Science for Life Laboratory, Department of Woman and Child Health, Karolinska Institute, Astrid Lindgren Children's Hospital, Stockholm, Sweden
| | - A Aperia
- Science for Life Laboratory, Department of Woman and Child Health, Karolinska Institute, Astrid Lindgren Children's Hospital, Stockholm, Sweden
| | - L Westin
- Science for Life Laboratory, Department of Woman and Child Health, Karolinska Institute, Astrid Lindgren Children's Hospital, Stockholm, Sweden
| | - J Moy
- National Resource for Imaging Mass Spectrometry, Cambridge, MA USA
| | - M Wang
- National Resource for Imaging Mass Spectrometry, Cambridge, MA USA
| | - C Guillermier
- Division of Genetics, Brigham and Women's Hospital, Harvard Medical School, Boston, MA USA ; National Resource for Imaging Mass Spectrometry, Cambridge, MA USA
| | - C Poczatek
- National Resource for Imaging Mass Spectrometry, Cambridge, MA USA
| | - C Lechene
- Division of Genetics, Brigham and Women's Hospital, Harvard Medical School, Boston, MA USA ; National Resource for Imaging Mass Spectrometry, Cambridge, MA USA
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26
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Illarionava NB, Brismar H, Aperia A, Gunnarson E. Role of Na,K-ATPase α1 and α2 isoforms in the support of astrocyte glutamate uptake. PLoS One 2014; 9:e98469. [PMID: 24901986 PMCID: PMC4046997 DOI: 10.1371/journal.pone.0098469] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2013] [Accepted: 05/03/2014] [Indexed: 01/28/2023] Open
Abstract
Glutamate released during neuronal activity is cleared from the synaptic space via the astrocytic glutamate/Na+ co-transporters. This transport is driven by the transmembrane Na+ gradient mediated by Na,K-ATPase. Astrocytes express two isoforms of the catalytic Na,K-ATPase α subunits; the ubiquitously expressed α1 subunit and the α2 subunit that has a more specific expression profile. In the brain α2 is predominantly expressed in astrocytes. The isoforms differ with regard to Na+ affinity, which is lower for α2. The relative roles of the α1 and α2 isoforms in astrocytes are not well understood. Here we present evidence that the presence of the α2 isoform may contribute to a more efficient restoration of glutamate triggered increases in intracellular sodium concentration [Na+]i. Studies were performed on primary astrocytes derived from E17 rat striatum expressing Na,K-ATPase α1 and α2 and the glutamate/Na+ co-transporter GLAST. Selective inhibition of α2 resulted in a modest increase of [Na+]i accompanied by a disproportionately large decrease in uptake of aspartate, an indicator of glutamate uptake. To compare the capacity of α1 and α2 to handle increases in [Na+]i triggered by glutamate, primary astrocytes overexpressing either α1 or α2 were used. Exposure to glutamate 200 µM caused a significantly larger increase in [Na+]i in α1 than in α2 overexpressing cells, and as a consequence restoration of [Na+]i, after glutamate exposure was discontinued, took longer time in α1 than in α2 overexpressing cells. Both α1 and α2 interacted with astrocyte glutamate/Na+ co-transporters via the 1st intracellular loop.
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Affiliation(s)
- Nina B. Illarionava
- Department of Women’s and Children’s Health, Karolinska Institutet, Stockholm, Sweden
| | - Hjalmar Brismar
- Department of Women’s and Children’s Health, Karolinska Institutet, Stockholm, Sweden
- Science for Life Laboratory, Department of Cell Physics, Royal Institute of Technology, Stockholm, Sweden
| | - Anita Aperia
- Department of Women’s and Children’s Health, Karolinska Institutet, Stockholm, Sweden
| | - Eli Gunnarson
- Department of Women’s and Children’s Health, Karolinska Institutet, Stockholm, Sweden
- * E-mail:
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27
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Fontana J, Kruusmägi M, Brismar H, Aperia A. Ca
2+
shuttling between endoplasmic reticulum and mitochondria underlying ouabain‐triggered Ca
2+
oscillations (1097.10). FASEB J 2014. [DOI: 10.1096/fasebj.28.1_supplement.1097.10] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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28
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Westin L, Reuss M, Lindskog M, Aperia A, Brismar H. Nanoscopic spine localization of Norbin, an mGluR5 accessory protein. BMC Neurosci 2014; 15:45. [PMID: 24670218 PMCID: PMC3976536 DOI: 10.1186/1471-2202-15-45] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2014] [Accepted: 03/19/2014] [Indexed: 12/13/2022] Open
Abstract
BACKGROUND Norbin is a neuron-specific, cytosolic protein that interacts with the metabotropic glutamate receptor 5 (mGluR5) and has a profound impact on mGluR5 signaling. Yet, little is known about its synaptic distribution. RESULTS Here we have analyzed the spatial relationship between Norbin, postsynaptic density protein 95 (PSD-95), actin and mGluR5 in spines using super-resolution microscopy. Norbin was found to have a high degree of colocalization with actin and a lower degree of colocalization with PSD-95. Co-immunoprecipitation studies confirmed that interaction occurs between Norbin and actin, but not between Norbin and PSD-95. Norbin was also found to have a high degree of colocalization with the perisynaptically located mGluR5. Findings based on structured illumination microscopy (3D-SIM) of exogenous expressed Norbin-GFP were confirmed by stimulated emission depletion microscopy (STED) of immunolabeled endogenous Norbin. CONCLUSIONS Norbin associates with actin rather than with PSD-95 in dendritic spines. Results regarding protein localization and colocalization performed with conventional confocal microscopy must be interpreted with great caution. The now available super-resolution microscopy techniques provide more accurate information about sub-cellular protein localization than previously was possible.
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Affiliation(s)
- Linda Westin
- Department of Women’s and Children’s Health, Science for Life Laboratory, Karolinska Institutet, 17165 Solna, Sweden
| | - Matthias Reuss
- Department of Applied Physics, Science for Life Laboratory, Royal Institute of Technology, 10691 Stockholm, Sweden
| | - Maria Lindskog
- Department of Neuroscience, Karolinska Institutet, 17177 Stockholm, Sweden
| | - Anita Aperia
- Department of Women’s and Children’s Health, Science for Life Laboratory, Karolinska Institutet, 17165 Solna, Sweden
| | - Hjalmar Brismar
- Department of Women’s and Children’s Health, Science for Life Laboratory, Karolinska Institutet, 17165 Solna, Sweden
- Department of Applied Physics, Science for Life Laboratory, Royal Institute of Technology, 10691 Stockholm, Sweden
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29
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Abstract
Abstract
Background
The dimensions of neuronal synapses suggest that optical super-resolution imaging methods are necessary for thorough investigation of protein distributions and interactions. Nanoscopic evaluation of neuronal samples has presented practical hurdles, but advancing methods are making synaptic protein topology and quantification measurements feasible. This work explores the application of Photoactivated Localization Microscopy (PALM) pointillistic super-resolution imaging for investigation of the membrane bound sodium pump, the Na,K-ATPase, in matured neurons.
Results
Two isoforms of the sodium pump (ATP1a1 and ATP1a3) were studied in cultured neurons using the PALM-compatible fluorescent proteins PAGFP and mEos. Nanoscopic imaging reveals a compartmentalized distribution of sodium pumps in dendritic spines. Several nanoclusters of pumps are typically found in the spine head and fewer in the spine neck. The density of sodium pumps was estimated from a quantification of detected single molecules at 450–650 pump copies/μm2 in the spine heads.
Conclusions
We have utilized PALM for dissection of nanoscale localization in mature cultured neurons and demonstrated similar topology and quantification estimates with PAGFP and mEos. PALM topology assessments of the sodium pump appeared similar to previous STED studies, though quantification estimates varied, implying that labeling strategies, sample analysis and choice of nanoscopic imaging method can be critical factors for correct molecular quantification.
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30
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Blom H, Rönnlund D, Scott L, Westin L, Widengren J, Aperia A, Brismar H. Spatial distribution of DARPP-32 in dendritic spines. PLoS One 2013; 8:e75155. [PMID: 24058659 PMCID: PMC3769233 DOI: 10.1371/journal.pone.0075155] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2012] [Accepted: 08/12/2013] [Indexed: 11/18/2022] Open
Abstract
The phosphoprotein DARPP-32 (dopamine and cyclic adenosine 3´, 5´-monophosphate-regulated phosphoprotein, 32 kDa) is an important component in the molecular regulation of postsynaptic signaling in neostriatum. Despite the importance of this phosphoprotein, there is as yet little known about the nanoscale distribution of DARPP-32. In this study we applied superresolution stimulated emission depletion microscopy (STED) to assess the expression and distribution of DARPP-32 in striatal neurons. Primary culture of striatal neurons were immunofluorescently labeled for DARPP-32 with Alexa-594 and for the dopamine D1 receptor (D1R) with atto-647N. Dual-color STED microscopy revealed discrete localizations of DARPP-32 and D1R in the spine structure, with clustered distributions in both head and neck. Dissected spine structures reveal that the DARPP-32 signal rarely overlapped with the D1R signal. The D1R receptor is positioned in an "aggregated" manner primarily in the spine head and to some extent in the neck, while DARPP-32 forms several neighboring small nanoclusters spanning the whole spine structure. The DARPP-32 clusters have a mean size of 52 +/- 6 nm, which is close to the resolution limit of the microscope and corresponds to the physical size of a few individual phosphoprotein immunocomplexes. Dissection of synaptic proteins using superresolution microscopy gives possibilities to reveal in better detail biologically relevant information, as compared to diffraction-limited microscopy. In this work, the dissected postsynaptic topology of the DARPP-32 phosphoprotein provides strong evidence for a compartmentalized and confined distribution in dendritic spines. The protein topology and the relatively low copy number of phosphoprotein provides a conception of DARPP-32's possibilities to fine-tune the regulation of synaptic signaling, which should have an impact on the performance of the neuronal circuits in which it is expressed.
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Affiliation(s)
- Hans Blom
- Science for Life Laboratory, Stockholm, Sweden
- Department of Applied Physics, Royal Institute of Technology, Stockholm, Sweden
| | - Daniel Rönnlund
- Department of Applied Physics, Royal Institute of Technology, Stockholm, Sweden
| | - Lena Scott
- Science for Life Laboratory, Stockholm, Sweden
- Department of Women’s and Children’s Health, Solna, Sweden
| | - Linda Westin
- Science for Life Laboratory, Stockholm, Sweden
- Department of Women’s and Children’s Health, Solna, Sweden
| | - Jerker Widengren
- Science for Life Laboratory, Stockholm, Sweden
- Department of Applied Physics, Royal Institute of Technology, Stockholm, Sweden
| | - Anita Aperia
- Science for Life Laboratory, Stockholm, Sweden
- Department of Women’s and Children’s Health, Solna, Sweden
| | - Hjalmar Brismar
- Science for Life Laboratory, Stockholm, Sweden
- Department of Applied Physics, Royal Institute of Technology, Stockholm, Sweden
- Department of Women’s and Children’s Health, Solna, Sweden
- * E-mail:
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31
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Fontana JM, Burlaka I, Khodus G, Brismar H, Aperia A. Calcium oscillations triggered by cardiotonic steroids. FEBS J 2013; 280:5450-5. [PMID: 23890276 DOI: 10.1111/febs.12448] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2013] [Revised: 07/18/2013] [Accepted: 07/19/2013] [Indexed: 01/19/2023]
Abstract
Na(+), K(+)-ATPase (NKA) is well known for its function as an ion pump. Studies during the last decade have revealed an additional role for NKA as a signal transducer. In this brief review, we describe how cardiotonic steroids, which are highly specific NKA ligands, trigger slow Ca(2+) oscillations by promoting the interaction between NKA and the inositol trisphosphate receptor, and how this Ca(2+) signal activates the NF-κB subunit p65 and increases the expression of the antiapoptotic factor Bcl-xL. The potential tissue-protective effects of this signal are discussed.
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Affiliation(s)
- Jacopo M Fontana
- Department of Women and Children's Health, Karolinska Institutet, Stockholm, Sweden
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32
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Burlaka I, Liu XL, Rebetz J, Arvidsson I, Yang L, Brismar H, Karpman D, Aperia A. Ouabain protects against Shiga toxin-triggered apoptosis by reversing the imbalance between Bax and Bcl-xL. J Am Soc Nephrol 2013; 24:1413-23. [PMID: 23744887 DOI: 10.1681/asn.2012101044] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022] Open
Abstract
Hemolytic uremic syndrome, a life-threatening disease often accompanied by acute renal failure, usually occurs after gastrointestinal infection with Shiga toxin 2 (Stx2)-producing Escherichia coli. Stx2 binds to the glycosphingolipid globotriaosylceramide receptor, expressed by renal epithelial cells, and triggers apoptosis by activating the apoptotic factor Bax. Signaling via the ouabain/Na,K-ATPase/IP3R/NF-κB pathway increases expression of Bcl-xL, an inhibitor of Bax, suggesting that ouabain might protect renal cells from Stx2-triggered apoptosis. Here, exposing rat proximal tubular cells to Stx2 in vitro resulted in massive apoptosis, upregulation of the apoptotic factor Bax, increased cleaved caspase-3, and downregulation of the survival factor Bcl-xL; co-incubation with ouabain prevented all of these effects. Ouabain activated the NF-κB antiapoptotic subunit p65, and the inhibition of p65 DNA binding abolished the antiapoptotic effect of ouabain in Stx2-exposed tubular cells. Furthermore, in vivo, administration of ouabain reversed the imbalance between Bax and Bcl-xL in Stx2-treated mice. Taken together, these results suggest that ouabain can protect the kidney from the apoptotic effects of Stx2.
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Affiliation(s)
- Ievgeniia Burlaka
- Department of Women's and Children's Health, Karolinska Institutet, Astrid Lindgren Children's Hospital, Research Lab, Stockholm, Sweden
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33
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Scott L, Bernhem K, Brismar H, Aperia A. Variability in the strength of AT
1
R Ca
2+
signaling. FASEB J 2013. [DOI: 10.1096/fasebj.27.1_supplement.903.6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Lena Scott
- Women's and Children's HealthKarolinska InstitutetStockholmSweden
| | | | - Hjalmar Brismar
- Women's and Children's HealthKarolinska InstitutetStockholmSweden
- Applied PhysicsRoyal Institute of Technology (KTH)StockholmSweden
| | - Anita Aperia
- Women's and Children's HealthKarolinska InstitutetStockholmSweden
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34
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Kruusmägi M, Liebmann T, Brismar H, Aperia A. Activity dependent regulation of Na,K‐ATPase α3 mobility in the postsynaptic membrane. FASEB J 2013. [DOI: 10.1096/fasebj.27.1_supplement.726.6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Markus Kruusmägi
- Dept. Women's and Children's healthKarolinska InstitutetStockholmSweden
| | - Thomas Liebmann
- Dept. Women's and Children's healthKarolinska InstitutetStockholmSweden
| | - Hjalmar Brismar
- Dept. Women's and Children's healthKarolinska InstitutetStockholmSweden
- Science for Life LaboratoryDept. of Cell PhysicsRoyal Institute of TechnologySolnaSweden
| | - Anita Aperia
- Dept. Women's and Children's healthKarolinska InstitutetStockholmSweden
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35
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Kruusmägi M, Azarias G, Connor S, Akkuratov EE, Brismar H, Broberger C, Aperia A. A specific and essential role for Na,K‐ATPase α3 in neurons co‐expressing α1 and α3. FASEB J 2013. [DOI: 10.1096/fasebj.27.1_supplement.726.7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Markus Kruusmägi
- Dept. Women's and Children's healthKarolinska InstitutetStockholmSweden
| | - Guillaume Azarias
- Dept. Women's and Children's healthKarolinska InstitutetStockholmSweden
| | - Siobhan Connor
- Dept. Women's and Children's healthKarolinska InstitutetStockholmSweden
- Dept. of NeuroscienceKarolinska InstitutetSolnaSweden
| | - Evgeny E Akkuratov
- International Center of BiotechnologyLomonosov Moscow State UniversityMoscowRussian Federation
| | - Hjalmar Brismar
- Dept. Women's and Children's healthKarolinska InstitutetStockholmSweden
- Science for Life LaboratoryDept. of Cell PhysicsRoyal Institute of TechnologySolnaSweden
| | | | - Anita Aperia
- Dept. Women's and Children's healthKarolinska InstitutetStockholmSweden
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36
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Miyakawa A, Ibarra C, Malmersjö S, Aperia A, Wiklund P, Uhlén P. Intracellular calcium release modulates polycystin-2 trafficking. BMC Nephrol 2013; 14:34. [PMID: 23398808 PMCID: PMC3577431 DOI: 10.1186/1471-2369-14-34] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2012] [Accepted: 02/06/2013] [Indexed: 01/26/2023] Open
Abstract
Background Polycystin-2 (PC2), encoded by the gene that is mutated in autosomal dominant polycystic kidney disease (ADPKD), functions as a calcium (Ca2+) permeable ion channel. Considerable controversy remains regarding the subcellular localization and signaling function of PC2 in kidney cells. Methods We investigated the subcellular PC2 localization by immunocytochemistry and confocal microscopy in primary cultures of human and rat proximal tubule cells after stimulating cytosolic Ca2+ signaling. Plasma membrane (PM) Ca2+ permeability was evaluated by Fura-2 manganese quenching using time-lapse fluorescence microscopy. Results We demonstrated that PC2 exhibits a dynamic subcellular localization pattern. In unstimulated human or rat proximal tubule cells, PC2 exhibited a cytosolic/reticular distribution. Treatments with agents that in various ways affect the Ca2+ signaling machinery, those being ATP, bradykinin, ionomycin, CPA or thapsigargin, resulted in increased PC2 immunostaining in the PM. Exposing cells to the steroid hormone ouabain, known to trigger Ca2+ oscillations in kidney cells, caused increased PC2 in the PM and increased PM Ca2+ permeability. Intracellular Ca2+ buffering with BAPTA, inositol 1,4,5-trisphosphate receptor (InsP3R) inhibition with 2-aminoethoxydiphenyl borate (2-APB) or Ca2+/Calmodulin-dependent kinase inhibition with KN-93 completely abolished ouabain-stimulated PC2 translocation to the PM. Conclusions These novel findings demonstrate intracellular Ca2+-dependent PC2 trafficking in human and rat kidney cells, which may provide new insight into cyst formations in ADPKD.
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Affiliation(s)
- Ayako Miyakawa
- Department of Medical Biochemistry and Biophysics, Karolinska Institutet, SE-171 77, Stockholm, Sweden
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37
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Azarias G, Kruusmägi M, Connor S, Akkuratov EE, Liu XL, Lyons D, Brismar H, Broberger C, Aperia A. A specific and essential role for Na,K-ATPase α3 in neurons co-expressing α1 and α3. J Biol Chem 2012. [PMID: 23195960 DOI: 10.1074/jbc.m112.425785] [Citation(s) in RCA: 92] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
Abstract
Most neurons co-express two catalytic isoforms of Na,K-ATPase, the ubiquitous α1, and the more selectively expressed α3. Although neurological syndromes are associated with α3 mutations, the specific role of this isoform is not completely understood. Here, we used electrophysiological and Na(+) imaging techniques to study the role of α3 in central nervous system neurons expressing both isoforms. Under basal conditions, selective inhibition of α3 using a low concentration of the cardiac glycoside, ouabain, resulted in a modest increase in intracellular Na(+) concentration ([Na(+)](i)) accompanied by membrane potential depolarization. When neurons were challenged with a large rapid increase in [Na(+)](i), similar to what could be expected following suprathreshold neuronal activity, selective inhibition of α3 almost completely abolished the capacity to restore [Na(+)](i) in soma and dendrite. Recordings of Na,K-ATPase specific current supported the notion that when [Na(+)](i) is elevated in the neuron, α3 is the predominant isoform responsible for rapid extrusion of Na(+). Low concentrations of ouabain were also found to disrupt cortical network oscillations, providing further support for the importance of α3 function in the central nervous system. The α isoforms express a well conserved protein kinase A consensus site, which is structurally associated with an Na(+) binding site. Following activation of protein kinase A, both the α3-dependent current and restoration of dendritic [Na(+)](i) were significantly attenuated, indicating that α3 is a target for phosphorylation and may participate in short term regulation of neuronal function.
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Affiliation(s)
- Guillaume Azarias
- Department of Women's and Children's Health, Karolinska Institutet, 171 76 Stockholm, Sweden
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38
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Abstract
The ability of cells to maintain sharp ion gradients across their membranes is the foundation for the molecular transport and electrical excitability. Across animal species and cell types, Na(+),K(+)-adenosine triphosphatase (ATPase) is arguably the most powerful contributor to this phenomenon. By producing a steep concentration difference of sodium and potassium between the intracellular and extracellular milieu, Na(+),K(+)-ATPase in the tubules provides the driving force for renal sodium reabsorption. Pump activity is downregulated by natriuretic hormones, such as dopamine, and is upregulated by antinatriuretic hormones, such as angiotensin. In the past decade, studies have revealed a novel and surprising role: that Na(+),K(+)-ATPase is a transducer of signals from extracellular to intracellular compartments. The signaling function of Na(+),K(+)-ATPase is activated by ouabain, a mammalian steroid hormone, at far lower concentrations than those that inhibit pump activity. By promoting growth and inhibiting apoptosis, activation of Na(+),K(+)-ATPase exerts tissue-protective effects. Ouabain-stimulated Na(+),K(+)-ATPase signaling has recently shown clinical promise by protecting the malnourished embryonic kidney from adverse developmental programming. A deeper understanding of the tissue-protective role of Na(+),K(+)-ATPase signaling and the regulation of Na(+),K(+)-ATPase pumping activity is of fundamental importance for the understanding and treatment of kidney diseases and kidney-related hypertension.
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Affiliation(s)
- Anita Aperia
- Department of Women's and Children's Health, Karolinska Institutet, Karolinska University Hospital, Astrid Lindgren Children's Hospital, Q2-09 SE-171 76 Stockholm, Sweden.
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39
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Aperia A. Preventive nephrology: a role for the pediatrician. J Pediatr 2012; 160:896-7. [PMID: 22402567 DOI: 10.1016/j.jpeds.2012.01.049] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/03/2012] [Accepted: 01/24/2012] [Indexed: 11/28/2022]
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40
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Burlaka I, Holtback U, Liu XL, Eklof AC, Fogo A, Aperia A. Activation of Na,KATPase signaling protects against glomerulo‐tubular disconnection. FASEB J 2012. [DOI: 10.1096/fasebj.26.1_supplement.lb463] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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41
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Li D, Scott L, Crambert S, Zelenin S, Eklöf AC, Di Ciano L, Ibarra F, Aperia A. Binding of losartan to angiotensin AT1 receptors increases dopamine D1 receptor activation. J Am Soc Nephrol 2011; 23:421-8. [PMID: 22193384 DOI: 10.1681/asn.2011040344] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
Abstract
Signaling through both angiotensin AT1 receptors (AT1R) and dopamine D1 receptors (D1R) modulates renal sodium excretion and arterial BP. AT1R and D1R form heterodimers, but whether treatment with AT1R antagonists functionally modifies D1R via allosterism is unknown. In this study, the AT1R antagonist losartan strengthened the interaction between AT1R and D1R and increased expression of D1R on the plasma membrane in vitro. In rat proximal tubule cells that express endogenous AT1R and D1R, losartan increased cAMP generation. Losartan increased cAMP in HEK 293a cells transfected with both AT1R and D1R, but it did not increase cAMP in cells transfected with either receptor alone, suggesting that losartan induces D1R activation. Furthermore, losartan did not increase cAMP in HEK 293a cells expressing AT1R and mutant S397/S398A D1R, which disrupts the physical interaction between AT1R and D1R. In vivo, administration of a D1R antagonist significantly attenuated the antihypertensive effect of losartan in rats with renal hypertension. Taken together, these data imply that losartan might exert its antihypertensive effect both by inhibiting AT1R signaling and by enhancing D1R signaling.
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Affiliation(s)
- Dong Li
- Department of Women's and Children's Health, Karolinska University Hospital, Q2:09, S-171 76 Stockholm, Sweden
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42
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Khodus GR, Kruusmägi M, Li J, Liu XL, Aperia A. Calcium signaling triggered by ouabain protects the embryonic kidney from adverse developmental programming. Pediatr Nephrol 2011; 26:1479-82. [PMID: 21424905 DOI: 10.1007/s00467-011-1816-y] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/14/2010] [Revised: 12/29/2010] [Accepted: 01/25/2011] [Indexed: 12/29/2022]
Abstract
The kidney is extraordinarily sensitive to adverse fetal programming. Malnutrition, the most common form of developmental challenge, retards formation of the kidney's functional units, the nephrons. The resulting low nephron endowment increases susceptibility to renal injury and disease. Using explanted rat embryonic kidneys, we found that the sodium-potassium-adenosine triphosphatase (Na, K-ATPase) ligand ouabain triggers, via the Na, K-ATPase/ inositol 1,4,5-trisphosphate receptor signalosome, a calcium-nuclear factor-kappa B (NF-κB) signal that protects kidney development from adverse effects of malnutrition. Serum deprivation resulted in severe retardation of nephron formation and robust increase in apoptotic rate, but in ouabain-exposed kidneys, no adverse effects of serum deprivation were observed. Depletion of intracellular calcium stores and inhibition of NF-κB activity abolished the rescuing effect of ouabain. Proof of principle that ouabain rescues development of embryonic kidneys exposed to malnutrition was obtained from studies on pregnant rats given low-protein diets and treated with ouabain or vehicle throughout pregnancy.
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Affiliation(s)
- Georgiy R Khodus
- Department of women's and children's health, Karolinska Institutet, Stockholm, Sweden
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43
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Blom H, RöNnlund D, Scott L, Spicarova Z, Rantanen V, Widengren J, Aperia A, Brismar H. Nearest neighbor analysis of dopamine D1 receptors and Na+-K+-ATPases in dendritic spines dissected by STED microscopy. Microsc Res Tech 2011; 75:220-8. [DOI: 10.1002/jemt.21046] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2011] [Accepted: 05/20/2011] [Indexed: 01/10/2023]
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44
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Blom H, Rönnlund D, Scott L, Spicarova Z, Widengren J, Bondar A, Aperia A, Brismar H. Spatial distribution of Na+-K+-ATPase in dendritic spines dissected by nanoscale superresolution STED microscopy. BMC Neurosci 2011; 12:16. [PMID: 21272290 PMCID: PMC3040715 DOI: 10.1186/1471-2202-12-16] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2010] [Accepted: 01/27/2011] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND The Na+,K+-ATPase plays an important role for ion homeostasis in virtually all mammalian cells, including neurons. Despite this, there is as yet little known about the isoform specific distribution in neurons. RESULTS With help of superresolving stimulated emission depletion microscopy the spatial distribution of Na+,K+-ATPase in dendritic spines of cultured striatum neurons have been dissected. The found compartmentalized distribution provides a strong evidence for the confinement of neuronal Na+,K+-ATPase (α3 isoform) in the postsynaptic region of the spine. CONCLUSIONS A compartmentalized distribution may have implications for the generation of local sodium gradients within the spine and for the structural and functional interaction between the sodium pump and other synaptic proteins. Superresolution microscopy has thus opened up a new perspective to elucidate the nature of the physiological function, regulation and signaling role of Na+,K+-ATPase from its topological distribution in dendritic spines.
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Affiliation(s)
- Hans Blom
- Department of Applied Physics, Royal Institute of Technology, Stockholm, Sweden
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Ringman Uggla A, von Schewelov K, Zelenina M, Aperia A, Frenckner B. Low pulmonary expression of epithelial Na(+) channel and Na(+), K(+)-ATPase in newborn infants with congenital diaphragmatic hernia. Neonatology 2011; 99:14-22. [PMID: 20588066 DOI: 10.1159/000292503] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/09/2009] [Accepted: 02/18/2010] [Indexed: 11/19/2022]
Abstract
BACKGROUND It has been suggested from several animal studies and clinical observations that congenital diaphragmatic hernia (CDH) with pulmonary hypoplasia is accompanied by a disturbed perinatal ion transport. This could lead to respiratory distress due to slower clearance of fetal lung fluid at birth. OBJECTIVES The purpose of this study was to determine whether CDH is related to changes in the expression of three rate-limiting transporter proteins in lung epithelium at birth. METHODS Tracheal aspirate was collected from 12 newborn infants with CDH and from 8 newborn control patients. Sampling was performed at postnatal age 18 and at 43 h in the CDH group and at 18 h in the control group. The protein abundance of α-, β- and γ-epithelial Na(+) channel (ENaC), aquaporin 5 and Na(+), K(+)-ATPase α(1) was analyzed using semiquantitative immunoblotting. RESULTS The levels of β-ENaC, γ-ENaC and Na(+), K(+)-ATPase α(1) collected at 18 h postnatally were significantly lower in CDH infants compared to control infants. In the CDH group, no significant difference in the expression of the ENaC subunits, Na(+), K(+)-ATPase α(1) or aquaporin 5 could be detected between the two sampling time points. CONCLUSIONS This downregulation may result in an abnormal lung fluid absorption which could be an important mechanism behind the respiratory distress seen in newborn CDH patients.
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Affiliation(s)
- Andreas Ringman Uggla
- Nordic Centre of Excellence for Research in Water Imbalance Related Disorders, Karolinska Institutet, Stockholm, Sweden
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Li Y, Zelenina M, Plat-Willson G, Marcoux MO, Aperia A, Casper C. Urinary aquaporin-2 excretion during ibuprofen or indomethacin treatment in preterm infants with patent ductus arteriosus. Acta Paediatr 2011; 100:59-66. [PMID: 21143292 DOI: 10.1111/j.1651-2227.2010.01943.x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
AIM Water channel AQP2 is the target for vasopressin (AVP) and a major determinant of urinary concentrating capacity. In mature kidneys, prostaglandins counteract the effect of AVP on AQP2 expression at functional sites. We investigated whether disturbances in water homeostasis in infants with patent ductus arteriosus (PDA) treated with prostaglandin inhibitors can be attributed to activation of AQP2. METHODS In 53 infants with symptomatic PDA (gestational age 24-33 weeks), 30 receiving ibuprofen and 23 indomethacin starting at 2-15 days of life, clinical and biochemical data were collected before treatment and after each dose of the drugs. Urinary AQP2 was determined by dot immunoblotting. RESULTS Urinary AQP2 level and osmolality were decreased in both groups. Urinary osmolality was overall low and correlated inversely with fluid uptake. In ibuprofen group, there was no correlation of AQP2 level with urinary osmolality. CONCLUSION There was no AQP2 upregulation in the infants. The low urinary osmolality and dissociation between urinary osmolality and urinary AQP2 level indicate that the fluid retention sometimes observed in PDA infants treated with prostaglandin inhibitors is not caused by increased levels of functional AQP2. Thus, knowledge about the renal physiology of the adult cannot always be transferred to the infant kidney.
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Affiliation(s)
- Yanhong Li
- Nordic Centre of Excellence for Research in Water Imbalance Related Disorders, Department of Women's and Children's Health, Karolinska Institutet, Stockholm, Sweden
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Li J, Khodus GR, Kruusmägi M, Kamali-Zare P, Liu XL, Eklöf AC, Zelenin S, Brismar H, Aperia A. Ouabain protects against adverse developmental programming of the kidney. Nat Commun 2010; 1:42. [PMID: 20975704 PMCID: PMC2963829 DOI: 10.1038/ncomms1043] [Citation(s) in RCA: 63] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2010] [Accepted: 06/29/2010] [Indexed: 11/28/2022] Open
Abstract
The kidney is extraordinarily sensitive to adverse fetal programming. Malnutrition, the most common form of developmental challenge, retards the formation of functional units, the nephrons. The resulting low nephron endowment increases susceptibility to renal injury and disease. Using explanted rat embryonic kidneys, we found that ouabain, the Na,K-ATPase ligand, triggers a calcium–nuclear factor-κB signal, which protects kidney development from adverse effects of malnutrition. To mimic malnutrition, kidneys were serum deprived for 24 h. This resulted in severe retardation of nephron formation and a robust increase in apoptosis. In ouabain-exposed kidneys, no adverse effects of serum deprivation were observed. Proof of principle that ouabain rescues development of embryonic kidneys exposed to malnutrition was obtained from studies on pregnant rats given a low-protein diet and treated with ouabain or vehicle throughout pregnancy. Thus, we have identified a survival signal and a feasible therapeutic tool to prevent adverse programming of kidney development. Poor maternal nutrition is known to affect fetal kidney development. This study shows that the sodium potassium ATPase ligand, ouabain, protects kidneys from cell death induced by serum starvation in vitro and from abnormal kidney development due to a low-protein diet in vivo.
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Affiliation(s)
- Juan Li
- Department of Women's and Children's Health, Karolinska Institutet, Stockholm 17176, Sweden
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Vieux R, Zelenina M, Aperia A, Hascoët JM. The renal adverse effects of ibuprofen are not mediated by AQP2 water channels. Pediatr Nephrol 2010; 25:1277-84. [PMID: 20390303 DOI: 10.1007/s00467-010-1487-0] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/04/2009] [Revised: 02/01/2010] [Accepted: 02/02/2010] [Indexed: 11/29/2022]
Abstract
The aim of this study was to determine (1) whether ibuprofen treatment in very preterm infants causes an increase in the renal water channel aquaporin-2 (AQP2) activity in the collecting duct via prostaglandin synthesis inhibition and (2) whether AQP2 activity remains disturbed long after ibuprofen treatment has ended. This was a prospective study involving premature infants with a gestation age of 27-31 weeks who received treatment between December 2005 and August 2006 in a tertiary Neonatal Intensive Care Unit. Each ibuprofen-treated infant was matched to two controls. Renal glomerular and tubular function were evaluated weekly for 1 month, and urinary AQP2 was measured by immuno-dotting. In total, 166 longitudinal samples were analyzed in 36 infants. Median [interquartile range] gestational age and birthweight were 28 [27.0-29.5] weeks and 1160 [1041-1242] g, respectively. Perinatal factors were similar in both groups. Urine output was significantly decreased in the ibuprofen-treated infants during the treatment. The urinary AQP2 level decreased significantly from day 2 to day 7 in both groups and was similar thereafter for the first month of life in ibuprofen-treated and control groups. Based on our results, we conclude that ibuprofen-induced oligo-anuria is not associated with a change in AQP2 activity and that ibuprofen does not affect AQP2 activity during the first month of life in very preterm neonates.
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Affiliation(s)
- Rachel Vieux
- Neonatal Department, Maternite Regionale Universitaire, 54042 Nancy, France
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Spicarova Z, Liu XL, Bondar A, Aperia A. Agrin C20 peptide provides neuroprotection by activating a Na,K‐ATPase/Inositol 1,4,5‐Trisphosphate receptor signaling pathway. FASEB J 2010. [DOI: 10.1096/fasebj.24.1_supplement.607.3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
| | - Xiao Li Liu
- Women's and Children's HealthKarolinska InstitutetSolnaSweden
| | - Alexander Bondar
- Women's and Children's HealthKarolinska InstitutetSolnaSweden
- Institute of Chemical Biology and Fundamental MedicineNovosibirskRussian Federation
| | - Anita Aperia
- Women's and Children's HealthKarolinska InstitutetSolnaSweden
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Wang H, Westin L, Nong Y, Birnbaum S, Bendor J, Brismar H, Nestler E, Aperia A, Flajolet M, Greengard P. Norbin is an endogenous regulator of metabotropic glutamate receptor 5 signaling. Science 2010; 326:1554-7. [PMID: 20007903 DOI: 10.1126/science.1178496] [Citation(s) in RCA: 99] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Metabotropic glutamate receptor 5 (mGluR5) is highly expressed in the mammalian central nervous system (CNS). It is involved in multiple physiological functions and is a target for treatment of various CNS disorders, including schizophrenia. We report that Norbin, a neuron-specific protein, physically interacts with mGluR5 in vivo, increases the cell surface localization of the receptor, and positively regulates mGluR5 signaling. Genetic deletion of Norbin attenuates mGluR5-dependent stable changes in synaptic function measured as long-term depression or long-term potentiation of synaptic transmission in the hippocampus. As with mGluR5 knockout mice or mice treated with mGluR5-selective antagonists, Norbin knockout mice showed a behavioral phenotype associated with a rodent model of schizophrenia, as indexed by alterations both in sensorimotor gating and psychotomimetic-induced locomotor activity.
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Affiliation(s)
- Hong Wang
- Laboratory of Molecular and Cellular Neuroscience, Rockefeller University, New York, NY 10065, USA
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