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Contreras RG, Torres-Carrillo A, Flores-Maldonado C, Shoshani L, Ponce A. Na +/K +-ATPase: More than an Electrogenic Pump. Int J Mol Sci 2024; 25:6122. [PMID: 38892309 PMCID: PMC11172918 DOI: 10.3390/ijms25116122] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2024] [Revised: 05/20/2024] [Accepted: 05/23/2024] [Indexed: 06/21/2024] Open
Abstract
The sodium pump, or Na+/K+-ATPase (NKA), is an essential enzyme found in the plasma membrane of all animal cells. Its primary role is to transport sodium (Na+) and potassium (K+) ions across the cell membrane, using energy from ATP hydrolysis. This transport creates and maintains an electrochemical gradient, which is crucial for various cellular processes, including cell volume regulation, electrical excitability, and secondary active transport. Although the role of NKA as a pump was discovered and demonstrated several decades ago, it remains the subject of intense research. Current studies aim to delve deeper into several aspects of this molecular entity, such as describing its structure and mode of operation in atomic detail, understanding its molecular and functional diversity, and examining the consequences of its malfunction due to structural alterations. Additionally, researchers are investigating the effects of various substances that amplify or decrease its pumping activity. Beyond its role as a pump, growing evidence indicates that in various cell types, NKA also functions as a receptor for cardiac glycosides like ouabain. This receptor activity triggers the activation of various signaling pathways, producing significant morphological and physiological effects. In this report, we present the results of a comprehensive review of the most outstanding studies of the past five years. We highlight the progress made regarding this new concept of NKA and the various cardiac glycosides that influence it. Furthermore, we emphasize NKA's role in epithelial physiology, particularly its function as a receptor for cardiac glycosides that trigger intracellular signals regulating cell-cell contacts, proliferation, differentiation, and adhesion. We also analyze the role of NKA β-subunits as cell adhesion molecules in glia and epithelial cells.
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Affiliation(s)
| | | | | | | | - Arturo Ponce
- Department of Physiology, Biophysics and Neurosciences, CINVESTAV-IPN, Mexico City 07360, Mexico; (R.G.C.); (A.T.-C.); (C.F.-M.); (L.S.)
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Blaustein MP, Hamlyn JM. Sensational site: the sodium pump ouabain-binding site and its ligands. Am J Physiol Cell Physiol 2024; 326:C1120-C1177. [PMID: 38223926 PMCID: PMC11193536 DOI: 10.1152/ajpcell.00273.2023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2023] [Revised: 12/22/2023] [Accepted: 01/10/2024] [Indexed: 01/16/2024]
Abstract
Cardiotonic steroids (CTS), used by certain insects, toads, and rats for protection from predators, became, thanks to Withering's trailblazing 1785 monograph, the mainstay of heart failure (HF) therapy. In the 1950s and 1960s, we learned that the CTS receptor was part of the sodium pump (NKA) and that the Na+/Ca2+ exchanger was critical for the acute cardiotonic effect of digoxin- and ouabain-related CTS. This "settled" view was upended by seven revolutionary observations. First, subnanomolar ouabain sometimes stimulates NKA while higher concentrations are invariably inhibitory. Second, endogenous ouabain (EO) was discovered in the human circulation. Third, in the DIG clinical trial, digoxin only marginally improved outcomes in patients with HF. Fourth, cloning of NKA in 1985 revealed multiple NKA α and β subunit isoforms that, in the rodent, differ in their sensitivities to CTS. Fifth, the NKA is a cation pump and a hormone receptor/signal transducer. EO binding to NKA activates, in a ligand- and cell-specific manner, several protein kinase and Ca2+-dependent signaling cascades that have widespread physiological effects and can contribute to hypertension and HF pathogenesis. Sixth, all CTS are not equivalent, e.g., ouabain induces hypertension in rodents while digoxin is antihypertensinogenic ("biased signaling"). Seventh, most common rodent hypertension models require a highly ouabain-sensitive α2 NKA and the elevated blood pressure is alleviated by EO immunoneutralization. These numerous phenomena are enabled by NKA's intricate structure. We have just begun to understand the endocrine role of the endogenous ligands and the broad impact of the ouabain-binding site on physiology and pathophysiology.
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Affiliation(s)
- Mordecai P Blaustein
- Department of Physiology, University of Maryland School of Medicine, Baltimore, Maryland, United States
- Department of Medicine, University of Maryland School of Medicine, Baltimore, Maryland, United States
| | - John M Hamlyn
- Department of Physiology, University of Maryland School of Medicine, Baltimore, Maryland, United States
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Binti S, Edeen PT, Fay DS. Loss of the Na + /K + cation pump CATP-1 suppresses nekl -associated molting defects. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.03.15.585189. [PMID: 38559007 PMCID: PMC10979969 DOI: 10.1101/2024.03.15.585189] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/04/2024]
Abstract
The conserved C. elegans protein kinases NEKL-2 and NEKL-3 regulate multiple steps of membrane trafficking and are required for larval molting. Through a forward genetic screen we identified a loss-of-function mutation in catp-1 as a suppressor of molting defects in synthetically lethal nekl-2; nekl-3 double mutants. catp-1 is predicted to encode a membrane- associated P4-type ATPase involved in Na + -K + exchange. Moreover, a mutation predicted to abolish CATP-1 ion-pump activity also suppressed nekl-2; nekl-3 mutants. Endogenously tagged CATP-1 was primarily expressed in epidermal (hypodermal) cells within punctate structures located at or near the apical plasma membrane. Through whole genome sequencing, we identified two additional nekl-2; nekl-3 suppressor strains containing coding-altering mutations in catp-1 but found that neither mutation, when introduced into nekl-2; nekl-3 mutants using CRISPR methods, was sufficient to elicit robust suppression of molting defects. Our data also suggested that the two catp-1 isoforms, catp-1a and catp-1b , may in some contexts be functionally redundant. On the basis of previously published studies, we tested the hypothesis that loss of catp-1 may suppress nekl -associated defects by inducing partial entry into the dauer pathway. Contrary to expectations, however, we failed to obtain evidence that loss of catp-1 suppresses nekl-2; nekl-3 defects through a dauer-associated mechanism or that loss of catp-1 leads to entry into the pre-dauer L2d stage. As such, loss of catp-1 may suppress nekl- associated molting and membrane trafficking defects by altering electrochemical gradients within membrane-bound compartments.
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Sheng X, Xia Z, Yang H, Hu R. The ubiquitin codes in cellular stress responses. Protein Cell 2024; 15:157-190. [PMID: 37470788 PMCID: PMC10903993 DOI: 10.1093/procel/pwad045] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2023] [Accepted: 07/04/2023] [Indexed: 07/21/2023] Open
Abstract
Ubiquitination/ubiquitylation, one of the most fundamental post-translational modifications, regulates almost every critical cellular process in eukaryotes. Emerging evidence has shown that essential components of numerous biological processes undergo ubiquitination in mammalian cells upon exposure to diverse stresses, from exogenous factors to cellular reactions, causing a dazzling variety of functional consequences. Various forms of ubiquitin signals generated by ubiquitylation events in specific milieus, known as ubiquitin codes, constitute an intrinsic part of myriad cellular stress responses. These ubiquitination events, leading to proteolytic turnover of the substrates or just switch in functionality, initiate, regulate, or supervise multiple cellular stress-associated responses, supporting adaptation, homeostasis recovery, and survival of the stressed cells. In this review, we attempted to summarize the crucial roles of ubiquitination in response to different environmental and intracellular stresses, while discussing how stresses modulate the ubiquitin system. This review also updates the most recent advances in understanding ubiquitination machinery as well as different stress responses and discusses some important questions that may warrant future investigation.
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Affiliation(s)
- Xiangpeng Sheng
- Key Laboratory of Systems Health Science of Zhejiang Province, School of Life Science, Hangzhou Institute for Advanced Study, University of Chinese Academy of Sciences, Hangzhou 310024, China
- State Key Laboratory of Molecular Biology, Shanghai Institute of Biochemistry and Cell Biology, Center for Excellence in Molecular Cell Science, Chinese Academy of Sciences, Shanghai 200031, China
- State Key Laboratory of Animal Disease Control, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin 150069, China
| | - Zhixiong Xia
- Key Laboratory of Systems Health Science of Zhejiang Province, School of Life Science, Hangzhou Institute for Advanced Study, University of Chinese Academy of Sciences, Hangzhou 310024, China
- State Key Laboratory of Molecular Biology, Shanghai Institute of Biochemistry and Cell Biology, Center for Excellence in Molecular Cell Science, Chinese Academy of Sciences, Shanghai 200031, China
| | - Hanting Yang
- Department of Neurology, State Key Laboratory of Medical Neurobiology, Institute for Translational Brain Research, MOE Frontiers Center for Brain Science, Zhongshan Hospital, Fudan University, Shanghai 200032, China
| | - Ronggui Hu
- Key Laboratory of Systems Health Science of Zhejiang Province, School of Life Science, Hangzhou Institute for Advanced Study, University of Chinese Academy of Sciences, Hangzhou 310024, China
- State Key Laboratory of Molecular Biology, Shanghai Institute of Biochemistry and Cell Biology, Center for Excellence in Molecular Cell Science, Chinese Academy of Sciences, Shanghai 200031, China
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Markov AG, Livanova AA, Fedorova AA, Kravtsova VV, Krivoi II. Chronic Ouabain Targets Pore-Forming Claudin-2 and Ameliorates Radiation-Induced Damage to the Rat Intestinal Tissue Barrier. Int J Mol Sci 2023; 25:278. [PMID: 38203449 PMCID: PMC10778734 DOI: 10.3390/ijms25010278] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2023] [Revised: 12/15/2023] [Accepted: 12/21/2023] [Indexed: 01/12/2024] Open
Abstract
Ionizing radiation (IR) causes disturbances in the functions of the gastrointestinal tract. Given the therapeutic potential of ouabain, a specific ligand of the Na,K-ATPase, we tested its ability to protect against IR-induced disturbances in the barrier and transport properties of the jejunum and colon of rats. Male Wistar rats were subjected to 6-day intraperitoneal injections of vehicle or ouabain (1 µg/kg/day). On the fourth day of injections, rats were exposed to total-body X-ray irradiation (10 Gy) or a sham irradiation. Isolated tissues were examined 72 h post-irradiation. Electrophysiological characteristics and paracellular permeability for sodium fluorescein were measured in an Ussing chamber. Histological analysis and Western blotting were also performed. In the jejunum tissue, ouabain exposure did not prevent disturbances in transepithelial resistance, paracellular permeability, histological characteristics, as well as changes in the expression of claudin-1, -3, -4, tricellulin, and caspase-3 induced by IR. However, ouabain prevented overexpression of occludin and the pore-forming claudin-2. In the colon tissue, ouabain prevented electrophysiological disturbances and claudin-2 overexpression. These observations may reveal a mechanism by which circulating ouabain maintains tight junction integrity under IR-induced intestinal dysfunction.
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Affiliation(s)
- Alexander G. Markov
- Department of General Physiology, St. Petersburg State University, 199034 St. Petersburg, Russia; (A.A.L.); (A.A.F.); (V.V.K.); (I.I.K.)
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Staehr C, Aalkjaer C, Matchkov V. The vascular Na,K-ATPase: clinical implications in stroke, migraine, and hypertension. Clin Sci (Lond) 2023; 137:1595-1618. [PMID: 37877226 PMCID: PMC10600256 DOI: 10.1042/cs20220796] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2023] [Revised: 10/05/2023] [Accepted: 10/09/2023] [Indexed: 10/26/2023]
Abstract
In the vascular wall, the Na,K-ATPase plays an important role in the control of arterial tone. Through cSrc signaling, it contributes to the modulation of Ca2+ sensitivity in vascular smooth muscle cells. This review focuses on the potential implication of Na,K-ATPase-dependent intracellular signaling pathways in severe vascular disorders; ischemic stroke, familial migraine, and arterial hypertension. We propose similarity in the detrimental Na,K-ATPase-dependent signaling seen in these pathological conditions. The review includes a retrospective proteomics analysis investigating temporal changes after ischemic stroke. The analysis revealed that the expression of Na,K-ATPase α isoforms is down-regulated in the days and weeks following reperfusion, while downstream Na,K-ATPase-dependent cSrc kinase is up-regulated. These results are important since previous studies have linked the Na,K-ATPase-dependent cSrc signaling to futile recanalization and vasospasm after stroke. The review also explores a link between the Na,K-ATPase and migraine with aura, as reduced expression or pharmacological inhibition of the Na,K-ATPase leads to cSrc kinase signaling up-regulation and cerebral hypoperfusion. The review discusses the role of an endogenous cardiotonic steroid-like compound, ouabain, which binds to the Na,K-ATPase and initiates the intracellular cSrc signaling, in the pathophysiology of arterial hypertension. Currently, our understanding of the precise control mechanisms governing the Na,K-ATPase/cSrc kinase regulation in the vascular wall is limited. Understanding the role of vascular Na,K-ATPase signaling is essential for developing targeted treatments for cerebrovascular disorders and hypertension, as the Na,K-ATPase is implicated in the pathogenesis of these conditions and may contribute to their comorbidity.
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Affiliation(s)
- Christian Staehr
- Department of Biomedicine, Aarhus University, Høegh-Guldbergsgade 10, 8000 Aarhus, Denmark
- Department of Renal Medicine, Aarhus University Hospital, Palle Juul-Jensens Boulevard 35, Aarhus, Denmark
| | - Christian Aalkjaer
- Department of Biomedicine, Aarhus University, Høegh-Guldbergsgade 10, 8000 Aarhus, Denmark
- Danish Cardiovascular Academy, Høegh-Guldbergsgade 10, 8000 Aarhus, Denmark
| | - Vladimir V. Matchkov
- Department of Biomedicine, Aarhus University, Høegh-Guldbergsgade 10, 8000 Aarhus, Denmark
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Sibarov DA, Zhuravleva ZD, Ilina MA, Boikov SI, Stepanenko YD, Karelina TV, Antonov SM. Unveiling the Role of Cholesterol in Subnanomolar Ouabain Rescue of Cortical Neurons from Calcium Overload Caused by Excitotoxic Insults. Cells 2023; 12:2011. [PMID: 37566090 PMCID: PMC10417153 DOI: 10.3390/cells12152011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2023] [Revised: 07/31/2023] [Accepted: 08/04/2023] [Indexed: 08/12/2023] Open
Abstract
Na/K-ATPase maintains transmembrane ionic gradients and acts as a signal transducer when bound to endogenous cardiotonic steroids. At subnanomolar concentrations, ouabain induces neuroprotection against calcium overload and apoptosis of neurons during excitotoxic stress. Here, the role of lipid rafts in interactions between Na/K-ATPase, sodium-calcium exchanger (NCX), and N-methy-D-aspartate receptors (NMDARs) was investigated. We analyzed 0.5-1-nanometer ouabain's effects on calcium responses and miniature post-synaptic current (mEPSCs) frequencies of cortical neurons during the action of NMDA in rat primary culture and brain slices. In both objects, ouabain attenuated NMDA-evoked calcium responses and prevented an increase in mEPSC frequency, while the cholesterol extraction by methyl-β-cyclodextrin prevented the effects. The data support the conclusions that (i) ouabain-induced inhibition of NMDA-elicited calcium response involves both pre- and post-synapse, (ii) the presence of astrocytes in the tripartite synapse is not critical for the ouabain effects, which are found to be similar in cell cultures and brain slices, and (iii) ouabain action requires the integrity of cholesterol-rich membrane microdomains in which the colocalization and functional interaction of NMDAR-transferred calcium influx, calcium extrusion by NCX, and Na/K-ATPase modulation of the exchanger occur. This regulation of the molecules by cardiotonic steroids may influence synaptic transmission, prevent excitotoxic neuronal death, and interfere with the pharmacological actions of neurological medicines.
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Affiliation(s)
| | | | | | | | | | | | - Sergei M. Antonov
- Sechenov Institute of Evolutionary Physiology and Biochemistry of the Russian Academy of Sciences, Torez pr. 44, 194223 Saint-Petersburg, Russia; (D.A.S.); (Z.D.Z.); (M.A.I.); (S.I.B.); (Y.D.S.); (T.V.K.)
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Rajanathan R, Pedersen TM, Guldbrandsen HO, Olesen LF, Thomsen MB, Bøtker HE, Matchkov VV. Augmented Ouabain-Induced Vascular Response Reduces Cardiac Efficiency in Mice with Migraine-Associated Mutation in the Na +, K +-ATPase α 2-Isoform. Biomedicines 2023; 11:biomedicines11020344. [PMID: 36830881 PMCID: PMC9953359 DOI: 10.3390/biomedicines11020344] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2022] [Revised: 01/22/2023] [Accepted: 01/23/2023] [Indexed: 01/27/2023] Open
Abstract
Heterozygous mice (α2+/G301R mice) for the migraine-associated mutation (G301R) in the Na+,K+-ATPase α2-isoform have decreased expression of cardiovascular α2-isoform. The α2+/G301R mice exhibit a pro-contractile vascular phenotype associated with decreased left ventricular ejection fraction. However, the integrated functional cardiovascular consequences of this phenotype remain to be addressed in vivo. We hypothesized that the vascular response to α2-isoform-specific inhibition of the Na+,K+-ATPase by ouabain is augmented in α2+/G301R mice leading to reduced cardiac efficiency. Thus, we aimed to assess the functional contribution of the α2-isoform to in vivo cardiovascular function of wild-type (WT) and α2+/G301R mice. Blood pressure, stroke volume, heart rate, total peripheral resistance, arterial dP/dt, and systolic time intervals were assessed in anesthetized WT and α2+/G301R mice. To address rate-dependent cardiac changes, cardiovascular variables were compared before and after intraperitoneal injection of ouabain (1.5 mg/kg) or vehicle during atrial pacing. The α2+/G301R mice showed an enhanced ouabain-induced increase in total peripheral resistance associated with reduced efficiency of systolic development compared to WT. When the hearts were paced, ouabain reduced stroke volume in α2+/G301R mice. In conclusion, the ouabain-induced vascular response was augmented in α2+/G301R mice with consequent suppression of cardiac function.
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Affiliation(s)
- Rajkumar Rajanathan
- Department of Biomedicine, Aarhus University, 8000 Aarhus, Denmark
- Correspondence:
| | | | | | | | - Morten B. Thomsen
- Department of Biomedical Sciences, University of Copenhagen, 1165 Copenhagen, Denmark
| | - Hans Erik Bøtker
- Department of Cardiology, Aarhus University Hospital, 8000 Aarhus, Denmark
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Ojo OB, Amoo ZA, Olaleye MT, Jha SK, Akinmoladun AC. Time and Brain Region-Dependent Excitatory Neurochemical Alterations in Bilateral Common Carotid Artery Occlusion Global Ischemia Model. Neurochem Res 2023; 48:96-116. [PMID: 36006597 DOI: 10.1007/s11064-022-03732-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2022] [Revised: 08/06/2022] [Accepted: 08/18/2022] [Indexed: 01/11/2023]
Abstract
Strict metabolic regulation in discrete brain regions leads to neurochemical changes in cerebral ischemia. Accumulation of extracellular glutamate is one of the early neurochemical changes that take place during cerebral ischemia. Understanding the sequential neurochemical processes involved in cerebral ischemia-mediated excitotoxicity before the clinical intervention of revascularization and reperfusion may greatly influence future therapeutic strategies for clinical stroke recovery. This study investigated the influence of time and brain regions on excitatory neurochemical indices in the bilateral common carotid artery occlusion (BCCAO) model of global ischemia. Male Wistar rats were subjected to BCCAO for 15 and 60 min to evaluate the effect of ischemia duration on excitatory neurochemical indices (dopamine level, glutamine synthetase, glutaminase, glutamate dehydrogenase, aspartate aminotransferase, monoamine oxidase, acetylcholinesterase, and Na+ K+ ATPase activities) in the discrete brain regions (cortex, striatum, cerebellum, and hippocampus). BCCAO without reperfusion caused marked time and brain region-dependent alterations in glutamatergic, glutaminergic, dopaminergic, monoaminergic, cholinergic, and electrogenic homeostasis. Prolonged BCCAO decreased cortical, striatal, and cerebellar glutamatergic, glutaminergic, dopaminergic, cholinergic, and electrogenic activities; increased hippocampal glutamatergic, glutaminergic, dopaminergic, and cholinergic activities, increased cortical and striatal monoaminergic activity; decreased cerebellar and hippocampal monoaminergic activity; and decreased hippocampal electrogenic activity. This suggests that excitatory neurotransmitters play a major role in the tissue-specific metabolic plasticity and reprogramming that takes place between the onset of cardiac arrest-mediated global ischemia and clinical intervention of recanalization. These tissue-specific neurochemical indices may serve as diagnostic and therapeutic strategies for mitigating the progression of ischemic damage before revascularization.
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Affiliation(s)
- Olubukola Benedicta Ojo
- Biochemical and Molecular Pharmacology and Toxicology Laboratories, Department of Biochemistry, School of Life Sciences, The Federal University of Technology, PMB 704, 340110, Akure, Nigeria. .,Sleep Research Laboratory, School of Life Sciences, Jawaharlal Nehru University, 110067, New Delhi, India.
| | - Zainab Abiola Amoo
- Biochemical and Molecular Pharmacology and Toxicology Laboratories, Department of Biochemistry, School of Life Sciences, The Federal University of Technology, PMB 704, 340110, Akure, Nigeria
| | - Mary Tolulope Olaleye
- Biochemical and Molecular Pharmacology and Toxicology Laboratories, Department of Biochemistry, School of Life Sciences, The Federal University of Technology, PMB 704, 340110, Akure, Nigeria
| | - Sushil Kumar Jha
- Sleep Research Laboratory, School of Life Sciences, Jawaharlal Nehru University, 110067, New Delhi, India
| | - Afolabi Clement Akinmoladun
- Biochemical and Molecular Pharmacology and Toxicology Laboratories, Department of Biochemistry, School of Life Sciences, The Federal University of Technology, PMB 704, 340110, Akure, Nigeria.
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Obradovic M, Sudar-Milovanovic E, Gluvic Z, Banjac K, Rizzo M, Isenovic ER. The Na +/K +-ATPase: A potential therapeutic target in cardiometabolic diseases. Front Endocrinol (Lausanne) 2023; 14:1150171. [PMID: 36926029 PMCID: PMC10011626 DOI: 10.3389/fendo.2023.1150171] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/23/2023] [Accepted: 02/14/2023] [Indexed: 03/08/2023] Open
Abstract
Cardiometabolic diseases (CMD) are a direct consequence of modern living and contribute to the development of multisystem diseases such as cardiovascular diseases and diabetes mellitus (DM). CMD has reached epidemic proportions worldwide. A sodium pump (Na+/K+-ATPase) is found in most eukaryotic cells' membrane and controls many essential cellular functions directly or indirectly. This ion transporter and its isoforms are important in the pathogenesis of some pathological processes, including CMD. The structure and function of Na+/K+-ATPase, its expression and distribution in tissues, and its interactions with known ligands such as cardiotonic steroids and other suspected endogenous regulators are discussed in this review. In addition, we reviewed recent literature data related to the involvement of Na+/K+-ATPase activity dysfunction in CMD, focusing on the Na+/K+-ATPase as a potential therapeutic target in CMD.
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Affiliation(s)
- Milan Obradovic
- Department of Radiobiology and Molecular Genetics, “VINČA“ Institute of Nuclear Sciences - National Institute of thе Republic of Serbia, University of Belgrade, Belgrade, Serbia
| | - Emina Sudar-Milovanovic
- Department of Radiobiology and Molecular Genetics, “VINČA“ Institute of Nuclear Sciences - National Institute of thе Republic of Serbia, University of Belgrade, Belgrade, Serbia
| | - Zoran Gluvic
- University Clinical-Hospital Centre Zemun-Belgrade, Clinic of Internal medicine, School of Medicine, University of Belgrade, Belgrade, Serbia
| | - Katarina Banjac
- Department of Radiobiology and Molecular Genetics, “VINČA“ Institute of Nuclear Sciences - National Institute of thе Republic of Serbia, University of Belgrade, Belgrade, Serbia
| | - Manfredi Rizzo
- School of Medicine, Promise Department, University of Palermo, Palermo, Italy
- *Correspondence: Manfredi Rizzo,
| | - Esma R. Isenovic
- Department of Radiobiology and Molecular Genetics, “VINČA“ Institute of Nuclear Sciences - National Institute of thе Republic of Serbia, University of Belgrade, Belgrade, Serbia
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11
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Short-Term Mild Hypoxia Modulates Na,K-ATPase to Maintain Membrane Electrogenesis in Rat Skeletal Muscle. Int J Mol Sci 2022; 23:ijms231911869. [PMID: 36233169 PMCID: PMC9570130 DOI: 10.3390/ijms231911869] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2022] [Revised: 09/26/2022] [Accepted: 09/30/2022] [Indexed: 11/17/2022] Open
Abstract
The Na,K-ATPase plays an important role in adaptation to hypoxia. Prolonged hypoxia results in loss of skeletal muscle mass, structure, and performance. However, hypoxic preconditioning is known to protect against a variety of functional impairments. In this study, we tested the possibility of mild hypoxia to modulate the Na,K-ATPase and to improve skeletal muscle electrogenesis. The rats were subjected to simulated high-altitude (3000 m above sea level) hypobaric hypoxia (HH) for 3 h using a hypobaric chamber. Isolated diaphragm and soleus muscles were tested. In the diaphragm muscle, HH increased the α2 Na,K-ATPase isozyme electrogenic activity and stably hyperpolarized the extrajunctional membrane for 24 h. These changes were accompanied by a steady increase in the production of thiobarbituric acid reactive substances as well as a decrease in the serum level of endogenous ouabain, a specific ligand of the Na,K-ATPase. HH also increased the α2 Na,K-ATPase membrane abundance without changing its total protein content; the plasma membrane lipid-ordered phase did not change. In the soleus muscle, HH protected against disuse (hindlimb suspension) induced sarcolemmal depolarization. Considering that the Na,K-ATPase is critical for maintaining skeletal muscle electrogenesis and performance, these findings may have implications for countermeasures in disuse-induced pathology and hypoxic therapy.
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Rognant S, Kravtsova VV, Bouzinova EV, Melnikova EV, Krivoi II, Pierre SV, Aalkjaer C, Jepps TA, Matchkov VV. The microtubule network enables Src kinase interaction with the Na,K-ATPase to generate Ca2+ flashes in smooth muscle cells. Front Physiol 2022; 13:1007340. [PMID: 36213229 PMCID: PMC9538378 DOI: 10.3389/fphys.2022.1007340] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2022] [Accepted: 09/05/2022] [Indexed: 12/03/2022] Open
Abstract
Background: Several local Ca2+ events are characterized in smooth muscle cells. We have previously shown that an inhibitor of the Na,K-ATPase, ouabain induces spatially restricted intracellular Ca2+ transients near the plasma membrane, and suggested the importance of this signaling for regulation of intercellular coupling and smooth muscle cell contraction. The mechanism behind these Na,K-ATPase-dependent “Ca2+ flashes” remains to be elucidated. In addition to its conventional ion transport function, the Na,K-ATPase is proposed to contribute to intracellular pathways, including Src kinase activation. The microtubule network is important for intracellular signaling, but its role in the Na,K-ATPase-Src kinase interaction is not known. We hypothesized the microtubule network was responsible for maintaining the Na,K-ATPase-Src kinase interaction, which enables Ca2+ flashes. Methods: We characterized Ca2+ flashes in cultured smooth muscle cells, A7r5, and freshly isolated smooth muscle cells from rat mesenteric artery. Cells were loaded with Ca2+-sensitive fluorescent dyes, Calcium Green-1/AM and Fura Red/AM, for ratiometric measurements of intracellular Ca2+. The Na,K-ATPase α2 isoform was knocked down with siRNA and the microtubule network was disrupted with nocodazole. An involvement of the Src signaling was tested pharmacologically and with Western blot. Protein interactions were validated with proximity ligation assays. Results: The Ca2+ flashes were induced by micromolar concentrations of ouabain. Knockdown of the α2 isoform Na,K-ATPase abolished Ca2+ flashes, as did inhibition of tyrosine phosphorylation with genistein and PP2, and the inhibitor of the Na,K-ATPase-dependent Src activation, pNaKtide. Ouabain-induced Ca2+ flashes were associated with Src kinase activation by phosphorylation. The α2 isoform Na,K-ATPase and Src kinase colocalized in the cells. Disruption of microtubule with nocodazole inhibited Ca2+ flashes, reduced Na,K-ATPase/Src interaction and Src activation. Conclusion: We demonstrate that the Na,K-ATPase-dependent Ca2+ flashes in smooth muscle cells require an interaction between the α2 isoform Na, K-ATPase and Src kinase, which is maintained by the microtubule network.
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Affiliation(s)
- Salomé Rognant
- Department of Biomedical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Violetta V. Kravtsova
- Department of General Physiology, St. Petersburg State University, St. Petersburg, Russia
| | | | | | - Igor I. Krivoi
- Department of General Physiology, St. Petersburg State University, St. Petersburg, Russia
| | - Sandrine V. Pierre
- Marshall Institute for Interdisciplinary Research, Marshall University, Huntington, WV, United States
| | | | - Thomas A. Jepps
- Department of Biomedical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Vladimir V. Matchkov
- Department of Biomedicine, Aarhus University, Aarhus, Denmark
- *Correspondence: Vladimir V. Matchkov,
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13
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Chronic Ouabain Prevents Radiation-Induced Reduction in the α2 Na,K-ATPase Function in the Rat Diaphragm Muscle. Int J Mol Sci 2022; 23:ijms231810921. [PMID: 36142836 PMCID: PMC9505176 DOI: 10.3390/ijms231810921] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2022] [Revised: 09/11/2022] [Accepted: 09/15/2022] [Indexed: 11/29/2022] Open
Abstract
The damaging effect of ionizing radiation (IR) on skeletal muscle Na,K-ATPase is an open field of research. Considering a therapeutic potential of ouabain, a specific ligand of the Na,K-ATPase, we tested its ability to protect against the IR-induced disturbances of Na,K-ATPase function in rat diaphragm muscle that co-expresses the α1 and α2 isozymes of this protein. Male Wistar rats (n = 26) were subjected to 6-day injections of vehicle (0.9% NaCl) or ouabain (1 µg/kg/day). On the fourth day of injections, rats were exposed to one-time total-body X-ray irradiation (10 Gy), or a sham irradiation. The isolated muscles were studied 72 h post-irradiation. IR decreased the electrogenic contribution of the α2 Na,K-ATPase without affecting its protein content, thereby causing sarcolemma depolarization. IR increased serum concentrations of ouabain, IL-6, and corticosterone, decreased lipid peroxidation, and changed cellular redox status. Chronic ouabain administration prevented IR-induced depolarization and loss of the α2 Na,K-ATPase electrogenic contribution without changing its protein content. This was accompanied with an elevation of ouabain concentration in circulation and with the lack of IR-induced suppression of lipid peroxidation. Given the crucial role of Na,K-ATPase in skeletal muscle performance, these findings may have therapeutic implications as countermeasures for IR-induced muscle pathology.
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14
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Zhang Z, Wang H, Lei X, Mehdi Ommati M, Tang Z, Yuan J. Bisphenol a exposure decreases learning ability through the suppression of mitochondrial oxidative phosphorylation in the hippocampus of male mice. Food Chem Toxicol 2022; 165:113167. [DOI: 10.1016/j.fct.2022.113167] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2021] [Revised: 05/13/2022] [Accepted: 05/17/2022] [Indexed: 11/25/2022]
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15
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Wang Q, Li N, Guo X, Huo B, Li R, Feng X, Fang Z, Zhu XH, Wang Y, Yi X, Wei X, Jiang DS. Comprehensive analysis identified a reduction in ATP1A2 mediated by ARID3A in abdominal aortic aneurysm. J Cell Mol Med 2022; 26:2866-2880. [PMID: 35441443 PMCID: PMC9097831 DOI: 10.1111/jcmm.17301] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2021] [Revised: 03/02/2022] [Accepted: 03/18/2022] [Indexed: 12/17/2022] Open
Abstract
Abdominal aortic aneurysm (AAA) is characterized by abdominal aorta dilatation and progressive structural impairment and is usually an asymptomatic and potentially lethal disease with a risk of rupture. To investigate the underlying mechanisms of AAA initiation and progression, seven AAA datasets related to human and mice were downloaded from the GEO database and reanalysed in the present study. After comprehensive bioinformatics analysis, we identified the enriched pathways associated with inflammation responses, vascular smooth muscle cell (VSMC) phenotype switching and cytokine secretion in AAA. Most importantly, we identified ATPase Na+/K+ transporting subunit alpha 2 (ATP1A2) as a key gene that was significantly decreased in AAA samples of both human and mice; meanwhile, its reduction mainly occurred in VSMCs of the aorta; this finding was validated by immunostaining and Western blot in human and mouse AAA samples. Furthermore, we explored the potential upstream transcription factors (TFs) that regulate ATP1A2 expression. We found that the TF AT‐rich interaction domain 3A (ARID3A) bound the promoter of ATP1A2 to suppress its expression. Our present study identified the ARID3A‐ATP1A2 axis as a novel pathway in the pathological processes of AAA, further elucidating the molecular mechanism of AAA and providing potential therapeutic targets for AAA.
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Affiliation(s)
- Qunhui Wang
- Division of Cardiothoracic and Vascular Surgery, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China
| | - Na Li
- Division of Cardiothoracic and Vascular Surgery, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China
| | - Xian Guo
- Division of Cardiothoracic and Vascular Surgery, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China
| | - Bo Huo
- Division of Cardiothoracic and Vascular Surgery, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China
| | - Rui Li
- Division of Cardiothoracic and Vascular Surgery, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China
| | - Xin Feng
- Division of Cardiothoracic and Vascular Surgery, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China
| | - Zemin Fang
- Division of Cardiothoracic and Vascular Surgery, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China
| | - Xue-Hai Zhu
- Division of Cardiothoracic and Vascular Surgery, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China.,Key Laboratory of Organ Transplantation, Ministry of Education, NHC Key Laboratory of Organ Transplantation, Key Laboratory of Organ Transplantation, Chinese Academy of Medical Sciences, Wuhan, Hubei, China
| | - Yixiang Wang
- Clinical medical College, Wuhan University of Science and Technology, Wuhan, Hubei, China
| | - Xin Yi
- Department of Cardiology, Renmin Hospital of Wuhan University, Wuhan, Hubei, China
| | - Xiang Wei
- Division of Cardiothoracic and Vascular Surgery, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China.,Key Laboratory of Organ Transplantation, Ministry of Education, NHC Key Laboratory of Organ Transplantation, Key Laboratory of Organ Transplantation, Chinese Academy of Medical Sciences, Wuhan, Hubei, China
| | - Ding-Sheng Jiang
- Division of Cardiothoracic and Vascular Surgery, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China.,Key Laboratory of Organ Transplantation, Ministry of Education, NHC Key Laboratory of Organ Transplantation, Key Laboratory of Organ Transplantation, Chinese Academy of Medical Sciences, Wuhan, Hubei, China
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16
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Tsumoto K, Kurata Y. Bifurcations and Proarrhythmic Behaviors in Cardiac Electrical Excitations. Biomolecules 2022; 12:biom12030459. [PMID: 35327651 PMCID: PMC8946197 DOI: 10.3390/biom12030459] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2022] [Revised: 03/09/2022] [Accepted: 03/14/2022] [Indexed: 12/23/2022] Open
Abstract
The heart is a hierarchical dynamic system consisting of molecules, cells, and tissues, and acts as a pump for blood circulation. The pumping function depends critically on the preceding electrical activity, and disturbances in the pattern of excitation propagation lead to cardiac arrhythmia and pump failure. Excitation phenomena in cardiomyocytes have been modeled as a nonlinear dynamical system. Because of the nonlinearity of excitation phenomena, the system dynamics could be complex, and various analyses have been performed to understand the complex dynamics. Understanding the mechanisms underlying proarrhythmic responses in the heart is crucial for developing new ways to prevent and control cardiac arrhythmias and resulting contractile dysfunction. When the heart changes to a pathological state over time, the action potential (AP) in cardiomyocytes may also change to a different state in shape and duration, often undergoing a qualitative change in behavior. Such a dynamic change is called bifurcation. In this review, we first summarize the contribution of ion channels and transporters to AP formation and our knowledge of ion-transport molecules, then briefly describe bifurcation theory for nonlinear dynamical systems, and finally detail its recent progress, focusing on the research that attempts to understand the developing mechanisms of abnormal excitations in cardiomyocytes from the perspective of bifurcation phenomena.
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17
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Trop-2, Na+/K+ ATPase, CD9, PKCα, cofilin assemble a membrane signaling super-complex that drives colorectal cancer growth and invasion. Oncogene 2022; 41:1795-1808. [DOI: 10.1038/s41388-022-02220-1] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2021] [Revised: 01/10/2022] [Accepted: 01/27/2022] [Indexed: 12/20/2022]
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18
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Dubrovskii VN, Orlova LA. Effect of Detergents on Activity and Magnesium-Dependent Properties of Different Isoforms of Na +,K +-ATPase in the Crude Membrane Fraction of Rat Cerebral Cortex. Bull Exp Biol Med 2021; 171:611-614. [PMID: 34617174 DOI: 10.1007/s10517-021-05279-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2021] [Indexed: 11/28/2022]
Abstract
We studied the effect of various detergents (Tween-20, Triton X-100, and sodium deoxycholate) on activity and magnesium-dependent properties of Na+,K+-ATPase of the crude membrane fraction of rat cerebral cortex. All studied detergents significantly increased activity of the studied enzyme in a concentration-dependent manner. Sodium deoxycholate provided significantly higher values Na+,K+-ATPase activity (by ≈50%) than Triton X-100 and Tween-20. In the presence of Triton X-100, a changed pattern of the dependence of enzyme activity on the concentration of magnesium ions in the incubation solution was noted. Separate measurement of activities of Na+,K+-ATPase isoforms made it possible to assume that changes in magnesium-dependent properties are due to the predominant effect of Triton X-100 on ouabain-sensitive α2- and α3-isoforms.
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19
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Livanova AA, Fedorova AA, Zavirsky AV, Bikmurzina AE, Krivoi II, Markov AG. Dose and time dependence of functional impairments in rat jejunum following ionizing radiation exposure. Physiol Rep 2021; 9:e14960. [PMID: 34337895 PMCID: PMC8326886 DOI: 10.14814/phy2.14960] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2021] [Revised: 06/19/2021] [Accepted: 06/19/2021] [Indexed: 12/12/2022] Open
Abstract
Ionizing radiation causes dramatic change in the transport and barrier functions of the intestine. The degree of radiation damage rate depends primarily on the absorbed dose and post-irradiation time. Variety of experimental protocols providing different time points and doses exist, with the lack of a common approach. In this study, to develop a unified convenient experimental scheme, dose and time dependence of barrier and transport properties of rat jejunum following ionizing radiation exposure were examined. Male Wistar rats were exposed to total body X-ray irradiation (2, 5, or 10 Gy). The control group was subjected to sham irradiation procedure. Samples of rat jejunum were obtained at 24, 48, or 72 h post-irradiation. Transepithelial resistance, short circuit current (Isc ), and paracellular permeability for sodium fluorescein of jejunum samples were measured in an Ussing chamber; a histological examination was also performed. These parameters were significantly disturbed only 72 h after irradiation at a dose of 10 Gy, which was accompanied by loss of crypt and villi, inflammatory infiltrations, and disintegration of enterocytes. This suggests that found experimental point (72 h after 10 Gy exposure) is the most appropriate for future study using rat jejunum as a model.
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Affiliation(s)
- Alexandra A. Livanova
- Department of General PhysiologySt. Petersburg State UniversitySt. PetersburgRussia
- Department of BiologyS.M. Kirov Military Medical AcademySt. PetersburgRussia
| | - Arina A. Fedorova
- Department of General PhysiologySt. Petersburg State UniversitySt. PetersburgRussia
| | - Alexander V. Zavirsky
- Department of Military Toxicology and Medical DefenseS.M. Kirov Military Medical AcademySt. PetersburgRussia
| | | | - Igor I. Krivoi
- Department of General PhysiologySt. Petersburg State UniversitySt. PetersburgRussia
| | - Alexander G. Markov
- Department of General PhysiologySt. Petersburg State UniversitySt. PetersburgRussia
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20
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Mohan S, Tiwari MN, Stanojević M, Biala Y, Yaari Y. Muscarinic regulation of the neuronal Na + /K + -ATPase in rat hippocampus. J Physiol 2021; 599:3735-3754. [PMID: 34148230 DOI: 10.1113/jp281460] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2021] [Accepted: 06/16/2021] [Indexed: 11/08/2022] Open
Abstract
KEY POINTS Stimulation of postsynaptic muscarinic receptors was shown to excite principal hippocampal neurons by modulating several membrane ion conductances. We show here that activation of postsynaptic muscarinic receptors also causes neuronal excitation by inhibiting Na+ /K+ -ATPase activity. Muscarinic Na+ /K+ -ATPase inhibition is mediated by two separate signalling pathways that lead downstream to enhanced Na+ /K+ -ATPase phosphorylation by activating protein kinase C and protein kinase G. Muscarinic excitation through Na+ /K+ -ATPase inhibition is probably involved in cholinergic modulation of hippocampal activity and may turn out to be a widespread mechanism of neuronal excitation in the brain. ABSTRACT Stimulation of muscarinic cholinergic receptors on principal hippocampal neurons enhances intrinsic neuronal excitability by modulating several membrane ion conductances. The electrogenic Na+ /K+ -ATPase (NKA; the 'Na+ pump') is a ubiquitous regulator of intrinsic neuronal excitability, generating a hyperpolarizing current to thwart excessive neuronal firing. Using electrophysiological and pharmacological methodologies in rat hippocampal slices, we show that neuronal NKA pumping activity is also subjected to cholinergic regulation. Stimulation of postsynaptic muscarinic, but not nicotinic, cholinergic receptors activates membrane-bound phospholipase C and hydrolysis of membrane-integral phosphatidylinositol 4,5-bisphosphate into diacylglycerol (DAG) and inositol 1,4,5-triphosphate (IP3 ). Along one signalling pathway, DAG activates protein kinase C (PKC). Along a second signalling pathway, IP3 causes Ca2+ release from the endoplasmic reticulum, facilitating nitric oxide (NO) production. The rise in NO levels stimulates cGMP synthesis by guanylate-cyclase, activating protein kinase G (PKG). The two pathways converge to cause partial NKA inhibition through enzyme phosphorylation by PKC and PKG, leading to a marked increase in intrinsic neuronal excitability. This novel mechanism of neuronal NKA regulation probably contributes to the cholinergic modulation of hippocampal activity in spatial navigation, learning and memory.
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Affiliation(s)
- Sandesh Mohan
- Department of Medical Neurobiology, Institute for Medical Research Israel-Canada, The Hebrew University-Hadassah School of Medicine, Jerusalem, 91120, Israel
| | - Manindra Nath Tiwari
- Department of Medical Neurobiology, Institute for Medical Research Israel-Canada, The Hebrew University-Hadassah School of Medicine, Jerusalem, 91120, Israel
| | - Marija Stanojević
- Department of Medical Neurobiology, Institute for Medical Research Israel-Canada, The Hebrew University-Hadassah School of Medicine, Jerusalem, 91120, Israel
| | - Yoav Biala
- Department of Medical Neurobiology, Institute for Medical Research Israel-Canada, The Hebrew University-Hadassah School of Medicine, Jerusalem, 91120, Israel
| | - Yoel Yaari
- Department of Medical Neurobiology, Institute for Medical Research Israel-Canada, The Hebrew University-Hadassah School of Medicine, Jerusalem, 91120, Israel
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21
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Kravtsova VV, Krivoi II. Molecular and Functional Heterogeneity of Na,K-ATPase in the Skeletal Muscle. J EVOL BIOCHEM PHYS+ 2021. [DOI: 10.1134/s0022093021040086] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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22
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Britto DT, Coskun D, Kronzucker HJ. Potassium physiology from Archean to Holocene: A higher-plant perspective. JOURNAL OF PLANT PHYSIOLOGY 2021; 262:153432. [PMID: 34034042 DOI: 10.1016/j.jplph.2021.153432] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/21/2021] [Revised: 04/22/2021] [Accepted: 04/22/2021] [Indexed: 05/27/2023]
Abstract
In this paper, we discuss biological potassium acquisition and utilization processes over an evolutionary timescale, with emphasis on modern vascular plants. The quintessential osmotic and electrical functions of the K+ ion are shown to be intimately tied to K+-transport systems and membrane energization. Several prominent themes in plant K+-transport physiology are explored in greater detail, including: (1) channel mediated K+ acquisition by roots at low external [K+]; (2) K+ loading of root xylem elements by active transport; (3) variations on the theme of K+ efflux from root cells to the extracellular environment; (4) the veracity and utility of the "affinity" concept in relation to transport systems. We close with a discussion of the importance of plant-potassium relations to our human world, and current trends in potassium nutrition from farm to table.
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Affiliation(s)
- Dev T Britto
- Faculty of Land and Food Systems, University of British Columbia, Vancouver, BC, V6T 1Z4, Canada; School of BioSciences, The University of Melbourne, Parkville, Victoria, 3010, Australia
| | - Devrim Coskun
- Département de Phytologie, Faculté des Sciences de l'Agriculture et de l'Alimentation (FSAA), Université Laval, Québec, QC, G1V 0A6, Canada
| | - Herbert J Kronzucker
- Faculty of Land and Food Systems, University of British Columbia, Vancouver, BC, V6T 1Z4, Canada; School of BioSciences, The University of Melbourne, Parkville, Victoria, 3010, Australia.
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23
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The Content of Minerals in the PCOS Group and the Correlation with the Parameters of Metabolism. Nutrients 2021; 13:nu13072214. [PMID: 34203167 PMCID: PMC8308369 DOI: 10.3390/nu13072214] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2021] [Revised: 06/18/2021] [Accepted: 06/25/2021] [Indexed: 11/17/2022] Open
Abstract
Polycystic ovary syndrome (PCOS) is a common disease in women of childbearing age. It is characterized by excessive androgen production, ovulation disorders, and developing metabolic syndrome. The aim of the study was to check whether selected minerals were related to the pathophysiological mechanisms of PCOS. The concentrations of minerals were determined using an inductively coupled atomic plasma-emission spectrometer (ICP-AES Jobin Yvon JY-24). Blood samples from PCOS and control women were collected, processed, and digested with a microwave system in women with PCOS with and without insulin resistance and in the control group. It was found: zinc (Zn)-10.14 ± 2.11, 9.89 ± 1.44 and 10.30 ± 1.67; nickel (Ni) 0.001 ± 0.0009, 0.001 ± 0.0006 and 0.002 ± 0.00001; iron (Fe) 868.0 ± 155.8, 835.3 ± 156.4 and 833.0 ± 94.6; manganese (Mn) 0.017 ± 0.006, 0.017 ± 0.008 and 0.020 ± 0.009; copper (Cu) 0.714 ± 0.129, 0.713 ± 0.114 and 0.761 ± 0.146; magnesium (Mg) 48.4 ± 8.3, 50.0 ± 8.4 and 45.3 ± 10.7; sodium (Na) 374.3 ± 84.3, 396.3 ± 66.6 and 367.9 ± 88.9; potassium (K) 2541.8 ± 330.9, 2409.6 ± 347.1 and 2336.9 ± 211.4 (µg/g). Some micronutrient deficiencies may have a negative effect on the lipid profile in PCOS patients (Ni, Na). Further studies are needed to better understand dependencies.
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24
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Kironenko TA, Milovanova KG, Zakharova AN, Sidorenko SV, Klimanova EA, Dyakova EY, Orlova AA, Negodenko ES, Kalinnikova YG, Orlov SN, Kapilevich LV. Effect of Dynamic and Static Load on the Concentration of Myokines in the Blood Plasma and Content of Sodium and Potassium in Mouse Skeletal Muscles. BIOCHEMISTRY (MOSCOW) 2021; 86:370-381. [PMID: 33838636 DOI: 10.1134/s0006297921030123] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Modulation of cytokine production by physical activity is of considerable interest, since it might be a promising strategy for correcting metabolic processes at both cellular and systemic levels. The content of IL-6, IL-8, and IL-15 in the plasma and the concentration of monovalent cations in the skeletal muscles of trained and untrained mice were studied at different periods after static and dynamic exercises. Dynamic loads caused an increase in the IL-6 content and decrease in the IL-15 content in the plasma of untrained mice, but produced no effect on the concentration of IL-8. In trained mice, the effect of a single load on the concentration of IL-6 and IL-15 in the plasma was enhanced, while the concentration of IL-8 decreased. Static loads produced a similar, but more pronounced effect on the plasma concentration of IL-6 and IL-15 compared the dynamic exercises; however, the concentration of IL-8 in response to the static exercise increased significantly. Prior training reinforced the described response for all the myokines studied. Dynamic load (swimming) increased the intracellular content of sodium but decreased the content of potassium in the mouse musculus soleus. Similar response was observed after the static load (grid hanging) in the musculus biceps; but no correlation of this response with the prior training was found. Possible mechanisms involved in the regulation of cytokine secretion after exercise are discussed, including triggering of gene transcription in response to changes in the [Na+]i/[K+]I ratio.
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Affiliation(s)
| | | | | | | | - Elizaveta A Klimanova
- National Research Tomsk State University, Tomsk, 634050, Russia. .,Faculty of Biology, Lomonosov Moscow State University, Moscow, 119234, Russia
| | | | - Anna A Orlova
- National Research Tomsk State University, Tomsk, 634050, Russia
| | | | | | - Sergei N Orlov
- National Research Tomsk State University, Tomsk, 634050, Russia.,Faculty of Biology, Lomonosov Moscow State University, Moscow, 119234, Russia
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25
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Chronic Ouabain Prevents Na,K-ATPase Dysfunction and Targets AMPK and IL-6 in Disused Rat Soleus Muscle. Int J Mol Sci 2021; 22:ijms22083920. [PMID: 33920198 PMCID: PMC8069997 DOI: 10.3390/ijms22083920] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2021] [Revised: 04/02/2021] [Accepted: 04/08/2021] [Indexed: 12/20/2022] Open
Abstract
Sustained sarcolemma depolarization due to loss of the Na,K-ATPase function is characteristic for skeletal muscle motor dysfunction. Ouabain, a specific ligand of the Na,K-ATPase, has a circulating endogenous analogue. We hypothesized that the Na,K-ATPase targeted by the elevated level of circulating ouabain modulates skeletal muscle electrogenesis and prevents its disuse-induced disturbances. Isolated soleus muscles from rats intraperitoneally injected with ouabain alone or subsequently exposed to muscle disuse by 6-h hindlimb suspension (HS) were studied. Conventional electrophysiology, Western blotting, and confocal microscopy with cytochemistry were used. Acutely applied 10 nM ouabain hyperpolarized the membrane. However, a single injection of ouabain (1 µg/kg) prior HS was unable to prevent the HS-induced membrane depolarization. Chronic administration of ouabain for four days did not change the α1 and α2 Na,K-ATPase protein content, however it partially prevented the HS-induced loss of the Na,K-ATPase electrogenic activity and sarcolemma depolarization. These changes were associated with increased phosphorylation levels of AMP-activated protein kinase (AMPK), its substrate acetyl-CoA carboxylase and p70 protein, accompanied with increased mRNA expression of interleikin-6 (IL-6) and IL-6 receptor. Considering the role of AMPK in regulation of the Na,K-ATPase, we suggest an IL-6/AMPK contribution to prevent the effects of chronic ouabain under skeletal muscle disuse.
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26
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Peter MCS, Gayathry R. Nitric oxide synthase (NOS) inhibitor L-NAME activates inducible NOS/NO system and drives multidimensional regulation of Na + /K + -ATPase in ionocyte epithelia of immersion-stressed air-breathing fish (Anabas testudineus Bloch). JOURNAL OF EXPERIMENTAL ZOOLOGY PART 2021; 335:396-416. [PMID: 33734617 DOI: 10.1002/jez.2454] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/23/2020] [Revised: 02/15/2021] [Accepted: 02/16/2021] [Indexed: 01/20/2023]
Abstract
Nitric oxide (NO) has been implicated in Na+ homeostatic control in water-breathing fishes. It is, however, uncertain whether air-breathing fish relies on NO to coordinate Na+ /K+ -ATPase (NKA)-driven Na+ transport during acute hypoxemia. We, thus, examined the action of nitric oxide synthase (NOS) inhibitor, L-NAME on NO availability, inducible NOS (iNOS) protein abundance and the regulatory dynamics of NKA in osmoregulatory epithelia of Anabas testudineus kept at induced hypoxemia. As expected in nonstressed fish, in vivo L-NAME (100 ng g-1 ) challenge for 30 min declined NO production in serum (40%) and osmoregulatory tissues (average 51.6%). Surprisingly, the magnitude of such reduction was less in hypoxemic fish after L-NAME challenge due to the net gain of NO (average 23.7%) in these tissues. Concurrently, higher iNOS protein abundance was found in branchial and intestinal epithelia of these hypoxemic fish. In nonstressed fish, L-NAME treatment inhibited the NKA activity in branchial and intestinal epithelia while stimulating its activity in renal epithelia. Interestingly in hypoxemic fish, L-NAME challenge restored the hypoxemia-inhibited NKA activity in branchial and renal epithelia. Similar recovery response was evident in the NKAα protein abundance in immunoblots and immunofluorescence images of branchial epithelia of these fish. Analysis of Nkaα1 isoform transcript abundance (Nkaα1a, α1b, α1c) also showed spatial and preferential regulation of Nkaα1 isoform switching. Collectively, the data indicate that L-NAME challenge activates iNOS/NO system in the branchial ionocyte epithelia of hypoxemia-stressed Anabas and demands multidimensional regulation of NKA to restore the Na+ transport rate probably to defend against acute hypoxemia.
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Affiliation(s)
- M C Subhash Peter
- Inter-University Centre for Evolutionary and Integrative Biology iCEIB, Thiruvananthapuram, Kerala, India.,Department of Zoology, University of Kerala, Thiruvananthapuram, Kerala, India
| | - R Gayathry
- Department of Zoology, University of Kerala, Thiruvananthapuram, Kerala, India
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27
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Jan V, Miš K, Nikolic N, Dolinar K, Petrič M, Bone A, Thoresen GH, Rustan AC, Marš T, Chibalin AV, Pirkmajer S. Effect of differentiation, de novo innervation, and electrical pulse stimulation on mRNA and protein expression of Na+,K+-ATPase, FXYD1, and FXYD5 in cultured human skeletal muscle cells. PLoS One 2021; 16:e0247377. [PMID: 33635930 PMCID: PMC7909653 DOI: 10.1371/journal.pone.0247377] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2020] [Accepted: 02/05/2021] [Indexed: 12/18/2022] Open
Abstract
Denervation reduces the abundance of Na+,K+-ATPase (NKA) in skeletal muscle, while reinnervation increases it. Primary human skeletal muscle cells, the most widely used model to study human skeletal muscle in vitro, are usually cultured as myoblasts or myotubes without neurons and typically do not contract spontaneously, which might affect their ability to express and regulate NKA. We determined how differentiation, de novo innervation, and electrical pulse stimulation affect expression of NKA (α and β) subunits and NKA regulators FXYD1 (phospholemman) and FXYD5 (dysadherin). Differentiation of myoblasts into myotubes under low serum conditions increased expression of myogenic markers CD56 (NCAM1), desmin, myosin heavy chains, dihydropyridine receptor subunit α1S, and SERCA2 as well as NKAα2 and FXYD1, while it decreased expression of FXYD5 mRNA. Myotubes, which were innervated de novo by motor neurons in co-culture with the embryonic rat spinal cord explants, started to contract spontaneously within 7–10 days. A short-term co-culture (10–11 days) promoted mRNA expression of myokines, such as IL-6, IL-7, IL-8, and IL-15, but did not affect mRNA expression of NKA, FXYDs, or myokines, such as musclin, cathepsin B, meteorin-like protein, or SPARC. A long-term co-culture (21 days) increased the protein abundance of NKAα1, NKAα2, FXYD1, and phospho-FXYD1Ser68 without attendant changes in mRNA levels. Suppression of neuromuscular transmission with α-bungarotoxin or tubocurarine for 24 h did not alter NKA or FXYD mRNA expression. Electrical pulse stimulation (48 h) of non-innervated myotubes promoted mRNA expression of NKAβ2, NKAβ3, FXYD1, and FXYD5. In conclusion, low serum concentration promotes NKAα2 and FXYD1 expression, while de novo innervation is not essential for upregulation of NKAα2 and FXYD1 mRNA in cultured myotubes. Finally, although innervation and EPS both stimulate contractions of myotubes, they exert distinct effects on the expression of NKA and FXYDs.
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Affiliation(s)
- Vid Jan
- Institute of Pathophysiology, Faculty of Medicine, University of Ljubljana, Ljubljana, Slovenia
| | - Katarina Miš
- Institute of Pathophysiology, Faculty of Medicine, University of Ljubljana, Ljubljana, Slovenia
| | - Natasa Nikolic
- Section for Pharmacology and Pharmaceutical Biosciences, Department of Pharmacy, University of Oslo, Oslo, Norway
| | - Klemen Dolinar
- Institute of Pathophysiology, Faculty of Medicine, University of Ljubljana, Ljubljana, Slovenia
| | - Metka Petrič
- Institute of Pathophysiology, Faculty of Medicine, University of Ljubljana, Ljubljana, Slovenia
| | - Andraž Bone
- Institute of Pathophysiology, Faculty of Medicine, University of Ljubljana, Ljubljana, Slovenia
| | - G. Hege Thoresen
- Section for Pharmacology and Pharmaceutical Biosciences, Department of Pharmacy, University of Oslo, Oslo, Norway
- Department of Pharmacology, Institute of Clinical Medicine, University of Oslo, Oslo, Norway
| | - Arild C. Rustan
- Section for Pharmacology and Pharmaceutical Biosciences, Department of Pharmacy, University of Oslo, Oslo, Norway
| | - Tomaž Marš
- Institute of Pathophysiology, Faculty of Medicine, University of Ljubljana, Ljubljana, Slovenia
| | - Alexander V. Chibalin
- National Research Tomsk State University, Tomsk, Russia
- Department of Molecular Medicine and Surgery, Integrative Physiology, Karolinska Institutet, Stockholm, Sweden
| | - Sergej Pirkmajer
- Institute of Pathophysiology, Faculty of Medicine, University of Ljubljana, Ljubljana, Slovenia
- * E-mail:
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Toxic effect of titanium dioxide nanoparticles on corneas in vitro and in vivo. Aging (Albany NY) 2021; 13:5020-5033. [PMID: 33534781 PMCID: PMC7950276 DOI: 10.18632/aging.202412] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2020] [Accepted: 08/05/2020] [Indexed: 12/12/2022]
Abstract
Titanium dioxide nanoparticles (TiO2 NPs) are widely used in a variety of areas. However, TiO2 NPs possess cytotoxicity which involves oxidative stress. Nuclear factor erythroid 2-related factor 2 (Nrf2) is a key molecule preventing cells from oxidative stress damage. In the current study, we explored the effect of Nrf2 signaling pathway in TiO2 NPs-induced corneal endothelial cell injury. Firstly, we found TiO2 NPs inhibited proliferation and damaged morphology and mitochondria of mouse primary corneal endothelial cells. Moreover, TiO2 NPs-induced oxidative damage of mouse primary corneal endothelial cells was inhibited by antioxidant NAC by evaluating production of reactive oxygen species (ROS), malondialdehyde (MDA), and activities of superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px). Next, flow cytometry analysis showed TiO2 NPs promoted apoptosis and cell cycle G2/M phase arrest of mouse primary corneal endothelial cells. Further investigation suggested that Nrf2 signaling pathway activation and the downregulation of ZO-1, β-catenin and Na-K-ATPase were involved in TiO2 NPs-induced mouse primary corneal endothelial cell injury. Our research highlighted the toxic effect of TiO2 NPs on corneas in vitro and in vivo, providing an alternative insight into TiO2 NPs-induced corneal endothelial cell injury.
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Circulating Ouabain Modulates Expression of Claudins in Rat Intestine and Cerebral Blood Vessels. Int J Mol Sci 2020; 21:ijms21145067. [PMID: 32709081 PMCID: PMC7404321 DOI: 10.3390/ijms21145067] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2020] [Revised: 07/13/2020] [Accepted: 07/14/2020] [Indexed: 12/20/2022] Open
Abstract
The ability of exogenous low ouabain concentrations to affect claudin expression and therefore epithelial barrier properties was demonstrated previously in cultured cell studies. We hypothesized that chronic elevation of circulating ouabain in vivo can affect the expression of claudins and tight junction permeability in different tissues. We tested this hypothesis in rats intraperitoneally injected with ouabain (1 μg/kg) for 4 days. Rat jejunum, colon and brain frontal lobes, which are variable in the expressed claudins and tight junction permeability, were examined. Moreover, the porcine jejunum cell line IPEC-J2 was studied. In IPEC-J2-cells, ouabain (10 nM, 19 days of incubation) stimulated epithelial barrier formation, increased transepithelial resistance and the level of cSrc-kinase activation by phosphorylation, accompanied with an increased expression of claudin-1, -5 and down-regulation of claudin-12; the expression of claudin-3, -4, -8 and tricellulin was not changed. In the jejunum, chronic ouabain increased the expression of claudin-1, -3 and -5 without an effect on claudin-2 and -4 expression. In the colon, only down-regulation of claudin-3 was observed. Chronic ouabain protected the intestine transepithelial resistance against functional injury induced by lipopolysaccharide treatment or by modeled acute microgravity; this regulation was most pronounced in the jejunum. Claudin-1 was also up-regulated in cerebral blood vessels. This was associated with reduction of claudin-3 expression while the expression of claudin-5 and occludin was not affected. Altogether, our results confirm that circulating ouabain can functionally and tissue-specifically affect barrier properties of epithelial and endothelial tissues via Na,K-ATPase-mediated modulation of claudins expression.
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Effects of Dynamic and Static Loads on the Concentration of Sodium and Potassium in Murine Skeletal Muscles. Bull Exp Biol Med 2020; 169:1-4. [DOI: 10.1007/s10517-020-04811-y] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2019] [Indexed: 10/24/2022]
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Marcus EA, Tokhtaeva E, Jimenez JL, Wen Y, Naini BV, Heard AN, Kim S, Capri J, Cohn W, Whitelegge JP, Vagin O. Helicobacter pylori infection impairs chaperone-assisted maturation of Na-K-ATPase in gastric epithelium. Am J Physiol Gastrointest Liver Physiol 2020; 318:G931-G945. [PMID: 32174134 PMCID: PMC7272721 DOI: 10.1152/ajpgi.00266.2019] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/03/2019] [Revised: 03/06/2020] [Accepted: 03/10/2020] [Indexed: 01/31/2023]
Abstract
Helicobacter pylori infection always induces gastritis, which may progress to ulcer disease or cancer. The mechanisms underlying mucosal injury by the bacteria are incompletely understood. Here, we identify a novel pathway for H. pylori-induced gastric injury, the impairment of maturation of the essential transport enzyme and cell adhesion molecule, Na-K-ATPase. Na-K-ATPase comprises α- and β-subunits that assemble in the endoplasmic reticulum (ER) before trafficking to the plasma membrane. Attachment of H. pylori to gastric epithelial cells increased Na-K-ATPase ubiquitylation, decreased its surface and total levels, and impaired ion balance. H. pylori did not alter degradation of plasmalemma-resident Na-K-ATPase subunits or their mRNA levels. Infection decreased association of α- and β-subunits with ER chaperone BiP and impaired assembly of α/β-heterodimers, as was revealed by quantitative mass spectrometry and immunoblotting of immunoprecipitated complexes. The total level of BiP was not altered, and the decrease in interaction with BiP was not observed for other BiP client proteins. The H. pylori-induced decrease in Na-K-ATPase was prevented by BiP overexpression, stopping protein synthesis, or inhibiting proteasomal, but not lysosomal, protein degradation. The results indicate that H. pylori impairs chaperone-assisted maturation of newly made Na-K-ATPase subunits in the ER independently of a generalized ER stress and induces their ubiquitylation and proteasomal degradation. The decrease in Na-K-ATPase levels is also seen in vivo in the stomachs of gerbils and chronically infected children. Further understanding of H. pylori-induced Na-K-ATPase degradation will provide insights for protection against advanced disease.NEW & NOTEWORTHY This work provides evidence that Helicobacter pylori decreases levels of Na-K-ATPase, a vital transport enzyme, in gastric epithelia, both in acutely infected cultured cells and in chronically infected patients and animals. The bacteria interfere with BiP-assisted folding of newly-made Na-K-ATPase subunits in the endoplasmic reticulum, accelerating their ubiquitylation and proteasomal degradation and decreasing efficiency of the assembly of native enzyme. Decreased Na-K-ATPase expression contributes to H. pylori-induced gastric injury.
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Affiliation(s)
- Elizabeth A Marcus
- Department of Pediatrics, David Geffen School of Medicine, University of California, Los Angeles, California
- Veterans Affairs Greater Los Angeles Health Care System, Los Angeles, California
| | - Elmira Tokhtaeva
- Department of Physiology, David Geffen School of Medicine, University of California, Los Angeles, California
- Veterans Affairs Greater Los Angeles Health Care System, Los Angeles, California
| | - Jossue L Jimenez
- Department of Pediatrics, David Geffen School of Medicine, University of California, Los Angeles, California
- Veterans Affairs Greater Los Angeles Health Care System, Los Angeles, California
| | - Yi Wen
- Department of Physiology, David Geffen School of Medicine, University of California, Los Angeles, California
- Veterans Affairs Greater Los Angeles Health Care System, Los Angeles, California
| | - Bita V Naini
- Department of Pathology and Laboratory Medicine, David Geffen School of Medicine, University of California, Los Angeles, California
| | - Ashley N Heard
- Department of Pediatrics, David Geffen School of Medicine, University of California, Los Angeles, California
- Veterans Affairs Greater Los Angeles Health Care System, Los Angeles, California
| | - Samuel Kim
- Veterans Affairs Greater Los Angeles Health Care System, Los Angeles, California
| | - Joseph Capri
- Pasarow Mass Spectrometry Laboratory, The Neuropsychiatric Insititute-Semel Institute, University of California, Los Angeles, California
| | - Whitaker Cohn
- Pasarow Mass Spectrometry Laboratory, The Neuropsychiatric Insititute-Semel Institute, University of California, Los Angeles, California
| | - Julian P Whitelegge
- Pasarow Mass Spectrometry Laboratory, The Neuropsychiatric Insititute-Semel Institute, University of California, Los Angeles, California
| | - Olga Vagin
- Department of Physiology, David Geffen School of Medicine, University of California, Los Angeles, California
- Veterans Affairs Greater Los Angeles Health Care System, Los Angeles, California
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Skeletal Muscle Na,K-ATPase as a Target for Circulating Ouabain. Int J Mol Sci 2020; 21:ijms21082875. [PMID: 32326025 PMCID: PMC7215781 DOI: 10.3390/ijms21082875] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2020] [Revised: 04/16/2020] [Accepted: 04/18/2020] [Indexed: 02/07/2023] Open
Abstract
While the role of circulating ouabain-like compounds in the cardiovascular and central nervous systems, kidney and other tissues in health and disease is well documented, little is known about its effects in skeletal muscle. In this study, rats were intraperitoneally injected with ouabain (0.1-10 µg/kg for 4 days) alone or with subsequent injections of lipopolysaccharide (1 mg/kg). Some rats were also subjected to disuse for 6 h by hindlimb suspension. In the diaphragm muscle, chronic ouabain (1 µg/kg) hyperpolarized resting potential of extrajunctional membrane due to specific increase in electrogenic transport activity of the 2 Na,K-ATPase isozyme and without changes in 1 and 2 Na,K-ATPase protein content. Ouabain (10-20 nM), acutely applied to isolated intact diaphragm muscle from not injected rats, hyperpolarized the membrane to a similar extent. Chronic ouabain administration prevented lipopolysaccharide-induced (diaphragm muscle) or disuse-induced (soleus muscle) depolarization of the extrajunctional membrane. No stimulation of the 1 Na,K-ATPase activity in human red blood cells, purified lamb kidney and Torpedo membrane preparations by low ouabain concentrations was observed. Our results suggest that skeletal muscle electrogenesis is subjected to regulation by circulating ouabain via the 2 Na,K-ATPase isozyme that could be important for adaptation of this tissue to functional impairment.
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Kravtsova VV, Bouzinova EV, Chibalin AV, Matchkov VV, Krivoi II. Isoform-specific Na,K-ATPase and membrane cholesterol remodeling in motor endplates in distinct mouse models of myodystrophy. Am J Physiol Cell Physiol 2020; 318:C1030-C1041. [PMID: 32293933 DOI: 10.1152/ajpcell.00453.2019] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Na,K-ATPase is a membrane transporter that is critically important for skeletal muscle function. Mdx and Bla/J mice are the experimental models of Duchenne muscular dystrophy and dysferlinopathy that are known to differ in the molecular mechanism of the pathology. This study examines the function of α1- and α2-Na,K-ATPase isozymes in respiratory diaphragm and postural soleus muscles from mdx and Bla/J mice compared with control С57Bl/6 mice. In diaphragm muscles, the motor endplate structure was severely disturbed (manifested by defragmentation) in mdx mice only. The endplate membrane of both Bla/J and mdx mice was depolarized due to specific loss of the α2-Na,K-ATPase electrogenic activity and its decreased membrane abundance. Total FXYD1 subunit (modulates Na,K-ATPase activity) abundance was decreased in both mouse models. However, the α2-Na,K-ATPase protein content as well as mRNA expression were specifically and significantly reduced only in mdx mice. The endplate membrane cholesterol redistribution was most pronounced in mdx mice. Soleus muscles from Bla/J and mdx mice demonstrated reduction of the α2-Na,K-ATPase membrane abundance and mRNA expression similar to the diaphragm muscles. In contrast to diaphragm, the α2-Na,K-ATPase protein content was altered in both Bla/J and mdx mice; membrane cholesterol re-distribution was not observed. Thus, the α2-Na,K-ATPase is altered in both Bla/J and mdx mouse models of chronic muscle pathology. However, despite some similarities, the α2-Na,K-ATPase and cholesterol abnormalities are more pronounced in mdx mice.
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Affiliation(s)
- Violetta V Kravtsova
- Department of General Physiology, St. Petersburg State University, St. Petersburg, Russia
| | | | | | | | - Igor I Krivoi
- Department of General Physiology, St. Petersburg State University, St. Petersburg, Russia
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Meza U, Delgado-Ramírez M, Romero-Méndez C, Sánchez-Armass S, Rodríguez-Menchaca AA. Functional marriage in plasma membrane: Critical cholesterol level-optimal protein activity. Br J Pharmacol 2020; 177:2456-2465. [PMID: 32060896 DOI: 10.1111/bph.15027] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2019] [Revised: 01/14/2020] [Accepted: 02/06/2020] [Indexed: 12/13/2022] Open
Abstract
In physiology, homeostasis refers to the condition where a system exhibits an optimum functional level. In contrast, any variation from this optimum is considered as a dysfunctional or pathological state. In this review, we address the proposal that a critical cholesterol level in the plasma membrane is required for the proper functioning of transmembrane proteins. Thus, membrane cholesterol depletion or enrichment produces a loss or gain of direct cholesterol-protein interaction and/or changes in the physical properties of the plasma membrane, which affect the basal or optimum activity of transmembrane proteins. Whether or not this functional switching is a generalized mechanism exhibited for all transmembrane proteins, or if it works just for an exclusive group of them, is an open question and an attractive subject to explore at a basic, pharmacological and clinical level.
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Affiliation(s)
- Ulises Meza
- Departamento de Fisiología y Biofísica, Facultad de Medicina, Universidad Autónoma de San Luis Potosí, San Luis Potosí, México
| | - Mayra Delgado-Ramírez
- Departamento de Fisiología y Biofísica, Facultad de Medicina, Universidad Autónoma de San Luis Potosí, San Luis Potosí, México
| | - Catalina Romero-Méndez
- Departamento de Fisiología y Biofísica, Facultad de Medicina, Universidad Autónoma de San Luis Potosí, San Luis Potosí, México
| | - Sergio Sánchez-Armass
- Departamento de Fisiología y Biofísica, Facultad de Medicina, Universidad Autónoma de San Luis Potosí, San Luis Potosí, México
| | - Aldo A Rodríguez-Menchaca
- Departamento de Fisiología y Biofísica, Facultad de Medicina, Universidad Autónoma de San Luis Potosí, San Luis Potosí, México
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Baggio S, Zenki K, Martins Silva A, Dos Santos TG, Rech G, Lazzarotto G, Dias RD, Mussulini BH, Rico EP, de Oliveira DL. Fetal alcohol spectrum disorders model alters the functionality of glutamatergic neurotransmission in adult zebrafish. Neurotoxicology 2020; 78:152-160. [PMID: 32173352 DOI: 10.1016/j.neuro.2020.03.003] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2019] [Revised: 03/06/2020] [Accepted: 03/06/2020] [Indexed: 01/21/2023]
Abstract
Fetal alcohol spectrum disorders (FASD) describe a wide range of ethanol-induced developmental disabilities, including craniofacial dysmorphology, and neurochemical and behavioral impairments. Zebrafish has become a popular animal model to evaluate the long-lasting effects of, both, severe and milder forms of FASD, including alterations to neurotransmission. Glutamate is one of the most affected neurotransmitter systems in ethanol-induced developmental disabilities. Therefore, the aim of the present study was to evaluate the functionality of the glutamatergic neurotransmitter system in an adult zebrafish FASD model. Zebrafish larvae (24 h post-fertilization) were exposed to ethanol (0.1 %, 0.25 %, 0.5 %, and 1%) for 2 h. After 4 months, the animals were euthanized and their brains were removed. The following variables were measured: glutamate uptake, glutamate binding, glutamine synthetase activity, Na+/K + ATPase activity, and high-resolution respirometry. Embryonic ethanol exposure reduced Na+-dependent glutamate uptake in the zebrafish brain. This reduction was positively modulated by ceftriaxone treatment, a beta-lactam antibiotic that promotes the expression of the glutamate transporter EAAT2. Moreover, the 0.5 % and 1% ethanol groups demonstrated reduced glutamate binding to brain membranes and decreased Na+/K + ATPase activity in adulthood. In addition, ethanol reduced glutamine synthetase activity in the 1% EtOH group. Embryonic ethanol exposure did not alter the immunocontent of the glutamate vesicular transporter VGLUT2 and the mitochondrial energetic metabolism of the brain in adulthood. Our results suggest that embryonic ethanol exposure may cause significant alterations in glutamatergic neurotransmission in the adult zebrafish brain.
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Affiliation(s)
- Suelen Baggio
- Laboratory of Cellular Neurochemistry, Programa De Pós-graduação Em Ciências Biológicas: Bioquímica, Departamento De Bioquímica, Instituto De Ciências Básicas Da Saúde, Universidade Federal Do Rio Grande Do Sul, Porto Alegre, RS, Brazil.
| | - Kamila Zenki
- Laboratory of Cellular Neurochemistry, Programa De Pós-graduação Em Ciências Biológicas: Bioquímica, Departamento De Bioquímica, Instituto De Ciências Básicas Da Saúde, Universidade Federal Do Rio Grande Do Sul, Porto Alegre, RS, Brazil
| | - Alberto Martins Silva
- Laboratory of Cellular Neurochemistry, Programa De Pós-graduação Em Ciências Biológicas: Bioquímica, Departamento De Bioquímica, Instituto De Ciências Básicas Da Saúde, Universidade Federal Do Rio Grande Do Sul, Porto Alegre, RS, Brazil
| | - Thainá Garbino Dos Santos
- Laboratory of Cellular Neurochemistry, Programa De Pós-graduação Em Ciências Biológicas: Bioquímica, Departamento De Bioquímica, Instituto De Ciências Básicas Da Saúde, Universidade Federal Do Rio Grande Do Sul, Porto Alegre, RS, Brazil
| | - Giovana Rech
- Laboratory of Cellular Neurochemistry, Programa De Pós-graduação Em Ciências Biológicas: Bioquímica, Departamento De Bioquímica, Instituto De Ciências Básicas Da Saúde, Universidade Federal Do Rio Grande Do Sul, Porto Alegre, RS, Brazil
| | - Gabriela Lazzarotto
- Laboratory of Cellular Neurochemistry, Programa De Pós-graduação Em Ciências Biológicas: Bioquímica, Departamento De Bioquímica, Instituto De Ciências Básicas Da Saúde, Universidade Federal Do Rio Grande Do Sul, Porto Alegre, RS, Brazil
| | - Renato Dutra Dias
- Laboratory of Cellular Neurochemistry, Programa De Pós-graduação Em Ciências Biológicas: Bioquímica, Departamento De Bioquímica, Instituto De Ciências Básicas Da Saúde, Universidade Federal Do Rio Grande Do Sul, Porto Alegre, RS, Brazil
| | - Ben Hur Mussulini
- Centre of New Technologies, University of Warsaw, Banacha 2C, Warsaw 02-097, Poland; ReMedy International Research Agenda Unit, University of Warsaw, Banacha 2C, Warsaw 02-097, Poland
| | - Eduardo Pacheco Rico
- Programa De Pós-Graduação Em Ciências Da Saúde, Universidade Do Extremo Sul Catarinense - UNESC, Av. Universitária, 1105, Bairro Universitário, 88806-000 Criciúma, SC, Brazil
| | - Diogo Losch de Oliveira
- Laboratory of Cellular Neurochemistry, Programa De Pós-graduação Em Ciências Biológicas: Bioquímica, Departamento De Bioquímica, Instituto De Ciências Básicas Da Saúde, Universidade Federal Do Rio Grande Do Sul, Porto Alegre, RS, Brazil
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Concentration-Dependent Effects of N-3 Long-Chain Fatty Acids on Na,K-ATPase Activity in Human Endothelial Cells. Molecules 2019; 25:molecules25010128. [PMID: 31905689 PMCID: PMC6982972 DOI: 10.3390/molecules25010128] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2019] [Revised: 12/20/2019] [Accepted: 12/25/2019] [Indexed: 11/17/2022] Open
Abstract
N-3 eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) seem to prevent endothelial dysfunction, a crucial step in atherogenesis, by modulating the levels of vasoactive molecules and by influencing Na,K-ATPase activity of vascular myocytes. The activity of endothelial Na,K-ATPase controls the ionic homeostasis of the neighboring cells, as well as cell function. However, controversy exists with respect to the vascular protective effect of EPA and DHA. We argue that this dispute might be due to the use of different concentrations of EPA and DHA in different studies. Therefore, this study was designed to define an optimal concentration of EPA and DHA to investigate endothelial function. For this purpose, human endothelial cells were exposed for 24 h to different concentrations of DHA or EPA (0–20 μM) to study membrane fluidity, peroxidation potential and Na,K-ATPase activity. EPA and DHA were linearly incorporated and this incorporation was mirrored by the linear increase of unsaturation index, membrane fluidity, and peroxidation potential. Na,K-ATPase activity peaked at 3.75 μM of EPA and DHA and then gradually decreased. It is noteworthy that DHA effects were always more pronounced than EPA. Concluding, low concentrations of EPA and DHA minimize peroxidation sensitivity and optimize Na,K-ATPase activity.
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Fedorova AA, Cornelius V, Amasheh S, Krivoi II, Markov AG. Low Ouabain Concentrations Stimulate Epithelial Barrier Formation in IPEC-J2 Cells. J EVOL BIOCHEM PHYS+ 2019. [DOI: 10.1134/s002209301903013x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
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Staehr C, Hangaard L, Bouzinova EV, Kim S, Rajanathan R, Boegh Jessen P, Luque N, Xie Z, Lykke-Hartmann K, Sandow SL, Aalkjaer C, Matchkov VV. Smooth muscle Ca 2+ sensitization causes hypercontractility of middle cerebral arteries in mice bearing the familial hemiplegic migraine type 2 associated mutation. J Cereb Blood Flow Metab 2019; 39. [PMID: 29513112 PMCID: PMC6681533 DOI: 10.1177/0271678x18761712] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Familial hemiplegic migraine type 2 (FHM2) is associated with inherited point-mutations in the Na,K-ATPase α2 isoform, including G301R mutation. We hypothesized that this mutation affects specific aspects of vascular function, and thus compared cerebral and systemic arteries from heterozygote mice bearing the G301R mutation (Atp1a2+/-G301R) with wild type (WT). Middle cerebral (MCA) and mesenteric small artery (MSA) function was compared in an isometric myograph. Cerebral blood flow was assessed with Laser speckle analysis. Intracellular Ca2+ and membrane potential were measured simultaneously. Protein expression was semi-quantified by immunohistochemistry. Protein phosphorylation was analysed by Western blot. MSA from Atp1a2+/-G301R and WT showed similar contractile responses. The Atp1a2+/-G301R MCA constricted stronger to U46619, endothelin and potassium compared to WT. This was associated with an increased depolarization, although the Ca2+ change was smaller than in WT. The enhanced constriction of Atp1a2+/-G301R MCA was associated with increased cSrc activation, stronger sensitization to [Ca2+]i and increased MYPT1 phosphorylation. These differences were abolished by cSrc inhibition. Atp1a2+/-G301R mice had reduced resting blood flow through MCA in comparison with WT mice. FHM2-associated mutation leads to elevated contractility of MCA due to sensitization of the contractile machinery to Ca2+, which is mediated via Na,K-ATPase/Src-kinase/MYPT1 signalling.
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Affiliation(s)
| | - Lise Hangaard
- 1 Department of Biomedicine, Aarhus University, Aarhus, Denmark
| | | | - Sukhan Kim
- 1 Department of Biomedicine, Aarhus University, Aarhus, Denmark
| | | | | | - Nathan Luque
- 2 Faculty of Science, Health, Education and Engineering, University of the Sunshine Coast, Queensland, Australia
| | - Zijian Xie
- 3 Marshall Institute for Interdisciplinary Research, Marshall University, Huntington, WV, USA
| | | | - Shaun L Sandow
- 2 Faculty of Science, Health, Education and Engineering, University of the Sunshine Coast, Queensland, Australia
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Markov AG, Vishnevskaya ON, Okorokova LS, Fedorova AA, Kruglova NM, Rybalchenko OV, Aschenbach JR, Amasheh S. Cholera toxin perturbs the paracellular barrier in the small intestinal epithelium of rats by affecting claudin-2 and tricellulin. Pflugers Arch 2019; 471:1183-1189. [PMID: 31222489 DOI: 10.1007/s00424-019-02294-z] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2018] [Revised: 06/12/2019] [Accepted: 06/13/2019] [Indexed: 01/07/2023]
Abstract
Cholera toxin is commonly known to induce chloride secretion of the intestine. In recent years, effects on epithelial barrier function have been reported, indicating synergistic co-regulation of transporters and tight junction proteins. Our current study focused on the analysis of cholera toxin effects on transepithelial resistance and on tight junction proteins, the latter known as structural correlates of barrier function. Ligated segments of the rat jejunum were injected with buffered solution containing cholera toxin (1 μg/ml) and incubated for 4 h. Subsequently, selfsame tissue specimens were mounted in Ussing chambers, and cholera toxin (1 μg/ml) was added on the apical side. Transepithelial resistance and permeability of sodium fluorescein (376 Da) were analyzed. Subsequently, tissues were removed, expression and localization of claudins were analyzed, and morphological studies were performed employing transmission electron microscopy and confocal laser scanning microscopy. Cholera toxin induced a marked decrease in transepithelial resistance in the rat jejunal epithelium and an increase in paracellular permeability for sodium fluorescein. Immunoblotting of tight junction proteins revealed an increase in claudin-2 signals, which was verified by confocal laser scanning immunofluorescence microscopy, and a decrease in tricellulin, whereas other tight junction proteins remained unchanged. Transmission electron microscopy showed a reduction in the number of microvilli after incubation with cholera toxin. Moreover, cholera toxin led to a widening of the intercellular space between enterocytes. In accordance with the commonly known prosecretory effect of cholera toxin, our study revealed a complementary effect on small intestinal barrier function and integrity, which might constitute a pathomechanism with high relevance for prevention and therapeutic approaches.
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Affiliation(s)
- Alexander G Markov
- Department of General Physiology, St. Petersburg State University, St. Petersburg, 197374, Russia
| | - Olga N Vishnevskaya
- Department of General Physiology, St. Petersburg State University, St. Petersburg, 197374, Russia
| | - Larisa S Okorokova
- Department of General Physiology, St. Petersburg State University, St. Petersburg, 197374, Russia
| | - Arina A Fedorova
- Department of General Physiology, St. Petersburg State University, St. Petersburg, 197374, Russia
| | - Natalia M Kruglova
- Department of General Physiology, St. Petersburg State University, St. Petersburg, 197374, Russia
| | - Oksana V Rybalchenko
- Faculty of Medicine, St. Petersburg State University, St. Petersburg, 197374, Russia
| | - Jörg R Aschenbach
- Institute of Veterinary Physiology, Freie Universität Berlin, 14163, Berlin, Germany
| | - Salah Amasheh
- Institute of Veterinary Physiology, Freie Universität Berlin, 14163, Berlin, Germany.
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Regulation of Neuronal Na +/K +-ATPase by Specific Protein Kinases and Protein Phosphatases. J Neurosci 2019; 39:5440-5451. [PMID: 31085608 DOI: 10.1523/jneurosci.0265-19.2019] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2019] [Revised: 03/27/2019] [Accepted: 04/16/2019] [Indexed: 01/13/2023] Open
Abstract
The Na+/K+-ATPase (NKA) is a ubiquitous membrane-bound enzyme responsible for generating and maintaining the Na+ and K+ electrochemical gradients across the plasmalemma of living cells. Numerous studies in non-neuronal tissues have shown that this transport mechanism is reversibly regulated by phosphorylation/dephosphorylation of the catalytic α subunit and/or associated proteins. In neurons, Na+/K+ transport by NKA is essential for almost all neuronal operations, consuming up to two-thirds of the neuron's energy expenditure. However, little is known about its cellular regulatory mechanisms. Here we have used an electrophysiological approach to monitor NKA transport activity in male rat hippocampal neurons in situ We report that this activity is regulated by a balance between serine/threonine phosphorylation and dephosphorylation. Phosphorylation by the protein kinases PKG and PKC inhibits NKA activity, whereas dephosphorylation by the protein phosphatases PP-1 and PP-2B (calcineurin) reverses this effect. Given that these kinases and phosphatases serve as downstream effectors in key neuronal signaling pathways, they may mediate the coupling of primary messengers, such as neurotransmitters, hormones, and growth factors, to the NKAs, through which multiple brain functions can be regulated or dysregulated.SIGNIFICANCE STATEMENT The Na+/K+-ATPase (NKA), known as the "Na+ pump," is a ubiquitous membrane-bound enzyme responsible for generating and maintaining the Na+ and K+ electrochemical gradients across the plasma membrane of living cells. In neurons, as in most types of cells, the NKA generates the negative resting membrane potential, which is the basis for almost all aspects of cellular function. Here we used an electrophysiological approach to monitor physiological NKA transport activity in single hippocampal pyramidal cells in situ We have found that neuronal NKA activity is oppositely regulated by phosphorylation and dephosphorylation, and we have identified the main protein kinases and phosphatases mediating this regulation. This fundamental form of NKA regulation likely plays a role in multiple brain functions.
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Abnormal Membrane Localization of α2 Isoform of Na,K-ATPase in m. soleus of Dysferlin-Deficient Mice. Bull Exp Biol Med 2019; 166:593-597. [DOI: 10.1007/s10517-019-04398-z] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2018] [Indexed: 01/01/2023]
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Staehr C, Rajanathan R, Matchkov VV. Involvement of the Na + ,K + -ATPase isoforms in control of cerebral perfusion. Exp Physiol 2019; 104:1023-1028. [PMID: 30768809 DOI: 10.1113/ep087519] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2018] [Accepted: 02/11/2019] [Indexed: 12/11/2022]
Abstract
NEW FINDINGS What is the topic of this review? In this review, we consider the role of the Na+ ,K+ -ATPase in cerebrovascular function and how it might be changed in familial hemiplegic migraine type 2 (FHM2). The primary focus is involvement of the Na+ ,K+ -ATPase isoforms in regulation of cerebrovascular tone. What advances does it highlight? In this review, we discuss three overall distinct mechanisms whereby the Na+ ,K+ -ATPase might be capable of regulating cerebrovascular tone. Furthermore, we discuss how changes in the Na+ ,K+ -ATPase in cerebral arteries might affect brain perfusion and thereby be involved in the pathology of FHM2. ABSTRACT Familial hemiplegic migraine type 2 (FHM2) has been characterized by biphasic changes in cerebral blood flow during a migraine attack, with initial hypoperfusion followed by abnormal hyperperfusion of the affected hemisphere. We suggested that FHM2-associated loss-of-function mutation(s) in the Na+ ,K+ -ATPase α2 isoform might be responsible for these biphasic changes in several ways. We found that reduced expression of the α2 isoform leads to sensitization of the contractile machinery to [Ca2+ ]i via Src kinase-dependent signal transduction. This change in sensitivity might be the underlying mechanism for both abnormally potentiated vasoconstriction and exaggerated vasorelaxation. Moreover, the functional significance of the Na+ ,K+ -ATPase α2 isoform in astrocytes provides for the possibility of elevated extracellular potassium signalling from astrocytic endfeet to the vascular wall in neurovascular coupling.
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Affiliation(s)
- Christian Staehr
- Department of Biomedicine, Health, Aarhus University, Aarhus C, Denmark
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Abstract
The Na,K-ATPase is an enzyme essential for ion homeostasis in all cells. Over the last decades, it has been well-established that in addition to the transport of Na+/K+ over the cell membrane, the Na,K-ATPase acts as a receptor transducing humoral signals intracellularly. It has been suggested that ouabain-like compounds serve as endogenous modulators of this Na,K-ATPase signal transduction. The molecular mechanisms underlying Na,K-ATPase signaling are complicated and suggest the confluence of divergent biological pathways. This review discusses recent updates on the Na,K-ATPase signaling pathways characterized or suggested in vascular smooth muscle cells. The conventional view on this signaling is based on a microdomain structure where the Na,K-ATPase controls the Na,Ca-exchanger activity via modulation of intracellular Na+ in the spatially restricted submembrane space. This, in turn, affects intracellular Ca2+ and Ca2+ load in the sarcoplasmic reticulum leading to modulation of contractility as well as gene expression. An ion-transport-independent signal transduction from the Na,K-ATPase is based on molecular interactions. This was primarily characterized in other cell types but recently also demonstrated in vascular smooth muscles. The downstream signaling from the Na,K-ATPase includes Src and phosphatidylinositol-4,5-bisphosphate 3 kinase signaling pathways and generation of reactive oxygen species. Moreover, in vascular smooth muscle cells the interaction between the Na,K-ATPase and proteins responsible for Ca2+ homeostasis, e.g., phospholipase C and inositol triphosphate receptors, contributes to an integration of the signaling pathways. Recent update on the Na,K-ATPase dependent intracellular signaling and the significance for physiological functions and pathophysiological changes are discussed in this review.
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Cholesterol and the Safety Factor for Neuromuscular Transmission. Int J Mol Sci 2019; 20:ijms20051046. [PMID: 30823359 PMCID: PMC6429197 DOI: 10.3390/ijms20051046] [Citation(s) in RCA: 31] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2019] [Revised: 02/23/2019] [Accepted: 02/24/2019] [Indexed: 12/12/2022] Open
Abstract
A present review is devoted to the analysis of literature data and results of own research. Skeletal muscle neuromuscular junction is specialized to trigger the striated muscle fiber contraction in response to motor neuron activity. The safety factor at the neuromuscular junction strongly depends on a variety of pre- and postsynaptic factors. The review focuses on the crucial role of membrane cholesterol to maintain a high efficiency of neuromuscular transmission. Cholesterol metabolism in the neuromuscular junction, its role in the synaptic vesicle cycle and neurotransmitter release, endplate electrogenesis, as well as contribution of cholesterol to the synaptogenesis, synaptic integrity, and motor disorders are discussed.
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Effects of Xingpi Kaiyu Fang on ATP, Na/K-ATPase, and Respiratory Chain Complexes of Hippocampus and Gastrocnemius Muscle in Depressed Rats. EVIDENCE-BASED COMPLEMENTARY AND ALTERNATIVE MEDICINE 2019; 2019:6054926. [PMID: 30719062 PMCID: PMC6335795 DOI: 10.1155/2019/6054926] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/07/2018] [Accepted: 12/19/2018] [Indexed: 12/18/2022]
Abstract
Objective To clarify the effectiveness and mechanism of the Chinese herbal formula Xingpi Kaiyu Fang (XPKYF) which is composed of American ginseng (Xi-Yang-shen), Radix curcumae (Yu-Jin), Acori tatarinowii rhizoma (Shi-Chang-pu), and Hypericum perforatum (Guan-Ye-lian-qiao) in depressed rats. Methods The rat model of depression was established by chronic unpredictable mild stress (CUMS) method for 6 weeks. Rats were randomly divided into six groups: control group, CUMS group, CUMS+XPKYF (3.6g/kg/d, 7.2g/kg/d, 14.4g/kg/d) groups, and CUMS+sertraline (4.5mg/kg/d) group. The sucrose preference test and the forced swimming test were performed to assess the rats' depression behavior. Mitochondrial ultrastructure was observed by transmission electron microscope and adenosine triphosphate (ATP) content, sodium potassium ATPase (Na/K-ATPase) activity, and mitochondrial respiratory chain complexes activities in hippocampus and gastrocnemius muscle were measured at the 14th and 42nd day. Results Rats subjected to six weeks of CUMS exhibited decreased sucrose preference ratio and prolonged immobility time. CUMS reduced ATP content in hippocampus, decreased Na/K-ATPase activity and respiratory chain complex I, III, and IV activities in hippocampus and gastrocnemius muscle, and damaged mitochondrial ultrastructure of hippocampus and gastrocnemius muscle. XPKYF at 14.4g/kg, the efficacy trend of which was better than the other drug groups, could prevent the stress-induced depressed behavior changes, inhibit the decrease of Na/K-ATPase activity in hippocampus, inhibit the decrease of respiratory chain complex III activities in hippocampus and gastrocnemius muscle, and protect mitochondria from ultrastructural damage. Conclusions Energy deficiency and damaged mitochondrial ultrastructure were found in hippocampus and gastrocnemius muscle of depressed rats established by CUMS. XPKYF could partly reverse alterations in ATP, Na/K-ATPase, and respiratory chain complexes of hippocampus and gastrocnemius muscle and protect mitochondria from ultrastructural damage. This provides another experimental evidence for the clinical application of XPKYF in the treatment of depression.
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Kravtsova VV, Timonina NA, Zakir’yanova GF, Sokolova AV, Mikhailov VM, Zefirov AL, Krivoi II. The Structural and Functional Characteristics of the Motor End Plates of Dysferlin-Deficient Mice. NEUROCHEM J+ 2018. [DOI: 10.1134/s1819712418040049] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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Dubrovskii VN, Shalabodov AD, Belkin AV. Effects of Neostigmine and Physostigmine on Activity of Na +,K +-ATPase in Various Subdivisions of Rat Brain. Bull Exp Biol Med 2018; 166:50-53. [PMID: 30450520 DOI: 10.1007/s10517-018-4287-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2018] [Indexed: 11/26/2022]
Abstract
The effects of intramuscular administration of neostigmine and physostigmine on Na+,K+-ATPase activity in various cerebral subdivisions were examined in rats. In CNS and peripheral tissues, both agents rapidly and significantly reduced activity of cholinesterases by 30-50%. The development of intoxication did not change the marker indices of stress reaction. In the cerebral cortex, physostigmine increased Na+,K+-ATPase activity, whereas neostigmine suppressed it. In addition, neostigmine decreased activity of this enzyme in the cerebellum. In contrast, both agents produced no effects on Na+,K+-ATPase activity in the striatum. The data corroborate the view on functional interaction between Na+,K+-ATPase and nicotinic cholinoreceptors in rat cerebral cortex.
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Vilchinskaya NA, Krivoi II, Shenkman BS. AMP-Activated Protein Kinase as a Key Trigger for the Disuse-Induced Skeletal Muscle Remodeling. Int J Mol Sci 2018; 19:ijms19113558. [PMID: 30424476 PMCID: PMC6274864 DOI: 10.3390/ijms19113558] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2018] [Revised: 11/02/2018] [Accepted: 11/09/2018] [Indexed: 12/25/2022] Open
Abstract
Molecular mechanisms that trigger disuse-induced postural muscle atrophy as well as myosin phenotype transformations are poorly studied. This review will summarize the impact of 5′ adenosine monophosphate -activated protein kinase (AMPK) activity on mammalian target of rapamycin complex 1 (mTORC1)-signaling, nuclear-cytoplasmic traffic of class IIa histone deacetylases (HDAC), and myosin heavy chain gene expression in mammalian postural muscles (mainly, soleus muscle) under disuse conditions, i.e., withdrawal of weight-bearing from ankle extensors. Based on the current literature and the authors’ own experimental data, the present review points out that AMPK plays a key role in the regulation of signaling pathways that determine metabolic, structural, and functional alternations in skeletal muscle fibers under disuse.
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Affiliation(s)
| | - Igor I Krivoi
- Department of General Physiology, St. Petersburg State University, St. Petersburg 199034, Russia.
| | - Boris S Shenkman
- Myology Laboratory, Institute of Biomedical Problems RAS, Moscow 123007, Russia.
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Bouzinova EV, Hangaard L, Staehr C, Mazur A, Ferreira A, Chibalin AV, Sandow SL, Xie Z, Aalkjaer C, Matchkov VV. The α2 isoform Na,K-ATPase modulates contraction of rat mesenteric small artery via cSrc-dependent Ca 2+ sensitization. Acta Physiol (Oxf) 2018; 224:e13059. [PMID: 29480968 DOI: 10.1111/apha.13059] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2017] [Revised: 02/06/2018] [Accepted: 02/16/2018] [Indexed: 12/11/2022]
Abstract
AIMS The Na,K-ATPase is involved in a large number of regulatory activities including cSrc-dependent signalling. Upon inhibition of the Na,K-ATPase with ouabain, cSrc activation is shown to occur in many cell types. This study tests the hypothesis that acute potentiation of agonist-induced contraction by ouabain is mediated through Na,K-ATPase-cSrc signalling-dependent sensitization of vascular smooth muscle cells to Ca2+ . METHODS Agonist-induced rat mesenteric small artery contraction was examined in vitro under isometric conditions and in vivo in anaesthetized rats. Arterial wall tension and [Ca2+ ]i in vascular smooth muscle cells were measured simultaneously. Changes in cSrc and myosin phosphatase targeting protein 1 (MYPT1) phosphorylation were analysed by Western blot. Protein expression was examined with immunohistochemistry. The α1 and α2 isoforms of the Na,K-ATPase were transiently downregulated by siRNA transfection in vivo. RESULTS Ten micromolar ouabain, but not digoxin, potentiated contraction to noradrenaline. This effect was not endothelium-dependent. Ouabain sensitized smooth muscle cells to Ca2+ , and this was associated with increased phosphorylation of cSrc and MYPT1. Inhibition of tyrosine kinase by genistein, PP2 or pNaKtide abolished the potentiating effect of ouabain on arterial contraction and Ca2+ sensitization. Downregulation of the Na,K-ATPase α2 isoform made arterial contraction insensitive to ouabain and tyrosine kinase inhibition. CONCLUSION Data suggest that micromolar ouabain potentiates agonist-induced contraction of rat mesenteric small artery via Na,K-ATPase-dependent cSrc activation, which increases Ca2+ sensitization of vascular smooth muscle cells by MYPT1 phosphorylation. This mechanism may be critical for acute control of vascular tone.
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Affiliation(s)
- E. V. Bouzinova
- Department of Biomedicine; Aarhus University; Aarhus C Denmark
| | - L. Hangaard
- Department of Biomedicine; Aarhus University; Aarhus C Denmark
| | - C. Staehr
- Department of Biomedicine; Aarhus University; Aarhus C Denmark
| | - A. Mazur
- Department of Biomedicine; Aarhus University; Aarhus C Denmark
| | - A. Ferreira
- Department of Biomedicine; Aarhus University; Aarhus C Denmark
| | - A. V. Chibalin
- Department of Molecular Medicine and Surgery; Integrative Physiology; Karolinska Institutet; Stockholm Sweden
| | - S. L. Sandow
- Faculty of Science, Health, Education and Engineering; University of the Sunshine Coast; Maroochydore Qld Australia
| | - Z. Xie
- Marshall Institute for Interdisciplinary Research; Marshall University; Huntington WV USA
| | - C. Aalkjaer
- Department of Biomedicine; Aarhus University; Aarhus C Denmark
| | - V. V. Matchkov
- Department of Biomedicine; Aarhus University; Aarhus C Denmark
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The Na,K-ATPase-Dependent Src Kinase Signaling Changes with Mesenteric Artery Diameter. Int J Mol Sci 2018; 19:ijms19092489. [PMID: 30142894 PMCID: PMC6164810 DOI: 10.3390/ijms19092489] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2018] [Revised: 08/17/2018] [Accepted: 08/21/2018] [Indexed: 01/09/2023] Open
Abstract
Inhibition of the Na,K-ATPase by ouabain potentiates vascular tone and agonist-induced contraction. These effects of ouabain varies between different reports. In this study, we assessed whether the pro-contractile effect of ouabain changes with arterial diameter and the molecular mechanism behind it. Rat mesenteric small arteries of different diameters (150–350 µm) were studied for noradrenaline-induced changes of isometric force and intracellular Ca2+ in smooth muscle cells. These functional changes were correlated to total Src kinase and Src phosphorylation assessed immunohistochemically. High-affinity ouabain-binding sites were semi-quantified with fluorescent ouabain. We found that potentiation of noradrenaline-sensitivity by ouabain correlates positively with an increase in arterial diameter. This was not due to differences in intracellular Ca2+ responses but due to sensitization of smooth muscle cell contractile machinery to Ca2+. This was associated with ouabain-induced Src activation, which increases with increasing arterial diameter. Total Src expression was similar in arteries of different diameters but the density of high-affinity ouabain binding sites increased with increasing arterial diameters. We suggested that ouabain binding induces more Src kinase activity in mesenteric small arteries with larger diameter leading to enhanced sensitization of the contractile machinery to Ca2+.
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