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Liang X, Pacuła-Miszewska AJ, Vartak R, Prajapati M, Zheng H, Zhao C, Mao G, Patel K, Fedosova NU, Ścianowski J, Billack B. N-3-Methylbutyl-benzisoselenazol-3(2H)-one Exerts Antifungal Activity In Vitro and in a Mouse Model of Vulvovaginal Candidiasis. Curr Issues Mol Biol 2024; 46:2480-2496. [PMID: 38534773 DOI: 10.3390/cimb46030157] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2024] [Revised: 03/04/2024] [Accepted: 03/04/2024] [Indexed: 03/28/2024] Open
Abstract
In the present work, we evaluated the antifungal activities of two novel ebselen analogs, N-allyl-benzisoselenazol-3(2H)-one (N-allyl-bs) and N-3-methylbutylbenzisoselenazol-3(2H)-one (N-3mb-bs). Colorimetric and turbidity assays were performed to determine the minimum inhibitory concentration (MIC) of these compounds in S1 (fluconazole-sensitive) and S2 (fluconazole-resistant) strains of C. albicans. N-3mb-bs was more active than the N-allyl-bs compound. It is noteworthy that the concentration of N-3mb-bs observed to inhibit fungal growth by 50% (18.2 µM) was similar to the concentration observed to inhibit the activity of the yeast plasma membrane H+-ATPase (Pma1p) by 50% (19.6 µM). We next implemented a mouse model of vulvovaginal candidiasis (VVC) using the S1 strain and examined the mouse and yeast proteins present in the vaginal lavage fluid using proteomics. The yeast proteins detected were predominately glycolytic enzymes or virulence factors associated with C. albicans while the mouse proteins present in the lavage fluid included eosinophil peroxidase, desmocollin-1, and gasdermin-A. We then utilized the N-3mb-bs compound (12.5 mg/kg) in the mouse VVC model and observed that it significantly reduced the vaginal fungal burden, histopathological changes in vagina tissue, and expression of myeloperoxidase (MPO). All in all, the present work has identified a potentially promising drug candidate for VVC treatment.
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Affiliation(s)
- Xiuyi Liang
- Department of Pharmaceutical Sciences, St. John's University, Queens, NY 11439, USA
| | | | - Richa Vartak
- Department of Pharmaceutical Sciences, St. John's University, Queens, NY 11439, USA
| | - Milankumar Prajapati
- Department of Pathology and Laboratory Medicine, Brown University, Providence, RI 02912, USA
| | - Haiyan Zheng
- Center for Advanced Biotechnology and Medicine, Piscataway, NJ 08854, USA
| | - Caifeng Zhao
- Center for Advanced Biotechnology and Medicine, Piscataway, NJ 08854, USA
| | - Ganming Mao
- Department of Pharmaceutical Sciences, St. John's University, Queens, NY 11439, USA
| | - Ketankumar Patel
- Department of Pharmaceutical Sciences, St. John's University, Queens, NY 11439, USA
| | | | - Jacek Ścianowski
- Faculty of Chemistry, Nicolaus Copernicus University, 87-100 Toruń, Poland
| | - Blase Billack
- Department of Pharmaceutical Sciences, St. John's University, Queens, NY 11439, USA
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Wehbe Z, Kreydiyyeh S. Cow milk-derived exosomes enhance the activity of the Na+/K+ ATPase in Caco-2 cells via EP3 and EP4 receptors. FOOD BIOSCI 2023. [DOI: 10.1016/j.fbio.2023.102606] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/03/2023]
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Rida R, Hodeify R, Kreydiyyeh S. Adverse effect of FTY720P on colonic Na + /K + ATPase is mediated via ERK, p38MAPK, PKC, and PI3K. J Appl Toxicol 2023; 43:220-229. [PMID: 35946054 DOI: 10.1002/jat.4375] [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: 06/11/2022] [Revised: 08/05/2022] [Accepted: 08/06/2022] [Indexed: 01/17/2023]
Abstract
FTY720P, an analogue of sphingosine 1-phosphate, has emerged lately as a potential causative agent of inflammatory bowel disease, in which electrolytes movements driven by the sodium gradient established by the Na+ /K+ ATPase are altered. We showed previously in Caco-2 cells, a 50% FTY720P-induced decrease in the ATPase activity, mediated via S1PR2 and PGE2. This work aims at delineating the mechanism underlying PGE2 release and at investigating if the ATPase inhibition is due to changes in its abundance. The activity of the ATPase and the localization of a GFP-tagged Na+ /K+ -ATPase α1 -subunit were assessed in cells treated with 7.5 nM FTY720P. The involvement of ERK, p38 MAPK, PKC, and PI3K was studied in cells treated with 7.5 nM FTY720P or 1 nM PGE2 in presence of their inhibitors, or by determining changes in the protein expression of their activated phosphorylated forms. Imaging data showed ∼30% reduction in the GFP-tagged Na+ /K+ ATPase at the plasma membrane. Both FTY720P and PGE2 showed, respectively, 50% and 60% reduction in ATPase activity that disappeared when p38 MAPK, PKC, and PI3K were inhibited individually but not with ERK inhibition. The effect of FTY720P was imitated by PMA, an activator of PKC. Western blotting revealed inhibition of ERK by FTY720P. It was concluded that FTY720P, through activation of S1PR2, downregulates the Na+ /K+ ATPase by inhibiting ERK, which in turn activates p38 MAPK leading to the sequential activation of PKC and PI3K, PGE2 release, and a decrease in the Na+ /K+ ATPase activity and membrane abundance.
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Affiliation(s)
- Reem Rida
- Department of Biology, Faculty of Arts and Sciences, American University of Beirut, Beirut, Lebanon
| | - Rawad Hodeify
- Department of Biotechnology, School of Arts and Sciences, American University of Ras Al Khaimah, Ras Al Khaimah, United Arab Emirates
| | - Sawsan Kreydiyyeh
- Department of Biology, Faculty of Arts and Sciences, American University of Beirut, Beirut, Lebanon
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4
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Fruergaard MU, Dach I, Andersen JL, Ozol M, Shasavar A, Quistgaard EM, Poulsen H, Fedosova NU, Nissen P. The Na,K-ATPase in complex with beryllium fluoride mimics an ATPase phosphorylated state. J Biol Chem 2022; 298:102317. [PMID: 35926706 PMCID: PMC9485054 DOI: 10.1016/j.jbc.2022.102317] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2022] [Revised: 07/23/2022] [Accepted: 07/25/2022] [Indexed: 10/29/2022] Open
Abstract
The Na+,K+-ATPase generates electrochemical gradients of Na+ and K+ across the plasma membrane via a functional cycle that includes various phosphoenzyme intermediates. However, the structure and function of these intermediates and how metal fluorides mimick them require further investigation. Here, we describe a 4.0 Å resolution crystal structure and functional properties of the pig kidney Na+,K+-ATPase stabilized by the inhibitor beryllium fluoride (denoted E2-BeFx). E2-BeFx is expected to mimic properties of the E2P phosphoenzyme, yet with unknown characteristics of ion and ligand binding. The structure resembles the E2P form obtained by phosphorylation from inorganic phosphate (Pi) and stabilized by cardiotonic steroids, including a low-affinity Mg2+ site near ion binding site II. Our anomalous Fourier analysis of the crystals soaked in Rb+ (a K+ congener) followed by a low-resolution rigid-body refinement (6.9-7.5 Å) revealed pre-occlusion transitions leading to activation of the dephosphorylation reaction. We show that the Mg2+ location indicates a site of initial K+ recognition and acceptance upon binding to the outward-open E2P state after Na+ release. Furthermore, using binding and activity studies, we find that the BeFx-inhibited enzyme is also able to bind ADP/ATP and Na+. These results relate the E2-BeFx complex to a transient K+- and ADP-sensitive E*P intermediate of the functional cycle of the Na+,K+-ATPase, prior to E2P.
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Affiliation(s)
- Marlene U Fruergaard
- DANDRITE - Nordic EMBL Partnership for Molecular Medicine, Aarhus University, Dept. Molecular Biology and Genetics, DK - 8000 Aarhus C, Denmark
| | - Ingrid Dach
- DANDRITE - Nordic EMBL Partnership for Molecular Medicine, Aarhus University, Dept. Molecular Biology and Genetics, DK - 8000 Aarhus C, Denmark
| | - Jacob L Andersen
- DANDRITE - Nordic EMBL Partnership for Molecular Medicine, Aarhus University, Dept. Molecular Biology and Genetics, DK - 8000 Aarhus C, Denmark; Department of Biomedicine, Aarhus University, DK - 8000 Aarhus C, Denmark
| | - Mette Ozol
- DANDRITE - Nordic EMBL Partnership for Molecular Medicine, Aarhus University, Dept. Molecular Biology and Genetics, DK - 8000 Aarhus C, Denmark
| | - Azadeh Shasavar
- DANDRITE - Nordic EMBL Partnership for Molecular Medicine, Aarhus University, Dept. Molecular Biology and Genetics, DK - 8000 Aarhus C, Denmark
| | - Esben M Quistgaard
- DANDRITE - Nordic EMBL Partnership for Molecular Medicine, Aarhus University, Dept. Molecular Biology and Genetics, DK - 8000 Aarhus C, Denmark
| | - Hanne Poulsen
- DANDRITE - Nordic EMBL Partnership for Molecular Medicine, Aarhus University, Dept. Molecular Biology and Genetics, DK - 8000 Aarhus C, Denmark
| | - Natalya U Fedosova
- Department of Biomedicine, Aarhus University, DK - 8000 Aarhus C, Denmark.
| | - Poul Nissen
- DANDRITE - Nordic EMBL Partnership for Molecular Medicine, Aarhus University, Dept. Molecular Biology and Genetics, DK - 8000 Aarhus C, Denmark.
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Influence of Nitric Oxide-Cyclic GMP and Oxidative STRESS on Amyloid-β Peptide Induced Decrease of Na,K-ATPase Activity in Rat Hippocampal Slices. J Membr Biol 2021; 254:463-473. [PMID: 34327545 DOI: 10.1007/s00232-021-00196-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2021] [Accepted: 07/19/2021] [Indexed: 12/11/2022]
Abstract
Amyloid-β peptide (Aβ) has been shown to cause synaptic dysfunction and can render neurons vulnerable to excitotoxicity and oxidative stress. Na,K-ATPase plays an important role to maintain cell ionic equilibrium and it can be modulated by N-methyl-D-aspartate (NMDA)-nitric oxide (NO)-cyclic GMP pathway. Disruption of NO synthase (NOS) activity and reactive oxygen species (ROS) production could lead to changes in Na,K-ATPase isoforms' activities that may be detrimental to the cells. Our aim was to evaluate the signaling pathways of Aβ in relation to NMDA-NOS-cyclic GMP versus oxidative stress on α1-/α2,3-Na,K-ATPase activities in rat hippocampal slices. Aβ1-40 induced a concentration-dependent increase of NOS activity and increased cyclic guanosine monophosphate (cGMP), TBARS (thiobarbituric acid reactive substances), and 3-Nitrotyrosine (3-NT)-modified protein levels in rat hippocampal slices. The increase in NOS activity and cyclic GMP levels induced by Aβ1-40 was completely blocked by MK-801 (inhibitor of NMDA receptor) and L-NAME (inhibitor of NOS) pre-treatment but changes in TBARS levels were only partially blocked by both compounds. The Aβ treatment also decreased Na,K-ATPase activity which was reverted by N-nitro-L-arginine methyl ester hydrochloride (L-NAME) but not by MK-801 pre-treatment. The decrease in enzyme activity induced by Aβ was isoform-specific since only α1-Na,K-ATPase was affected. These findings suggest that the activation of NMDA-NOS signaling cascade linked to α2,3-Na,K-ATPase activity may mediate an adaptive, neuroprotective response to Aβ in rat hippocampus.
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Abo El Gheit RE, Atef MM, Badawi GA, Elwan WM, Alshenawy HA, Emam MN. Role of serine protease inhibitor, ulinastatin, in rat model of hepatic encephalopathy: aquaporin 4 molecular targeting and therapeutic implication. J Physiol Biochem 2020; 76:573-586. [PMID: 32794154 DOI: 10.1007/s13105-020-00762-0] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2020] [Accepted: 08/09/2020] [Indexed: 12/13/2022]
Abstract
Hepatic encephalopathy (HE) is a devastating neuropsychiatric presentation of the advanced hepatic insufficiency. It is associated with high morbidity and mortality. Aquaporin-4 (AQP4), the principal astrocyte water channel, is primarily involved in brain edema development. Ulinastatin (ULI) is a potent protease inhibitor, extracted from fresh human urine. We hypothesized that ULI could be neuroprotective in acute HE through molecular targeting of brain AQP4, which is known to be upregulated in HE. To induce acute liver failure (ALF), the rats were acutely intoxicated with thioacetamide (TAA). Animals were randomized into HE- and ULI-treated HE groups, with control normal group. Total bilirubin, albumin, serum aminotransferases, and serum/brain ammonia/proinflammatory cytokines, blood-brain barrier (BBB) integrity/tight junction proteins, brain water content, and neurological scores were assessed. Additionally, brain AQP4 and α-Syntrophin mRNA expression and protein levels were evaluated by quantitative real-time PCR and enzyme-linked immunosorbent assay, respectively. Brain and liver tissues were stripped and processed for further microscopic and histological analyses. ULI exerted potent dual neuro/hepato protective potential, improved neurological score, animals' survival, ameliorated brain edema, probably via anti-inflammatory activity, preserved BBB integrity, down-regulated AQP4 expression, and membrane polarization by decreased α-syntrophin level, with rescued brain bioenergetics. ULI could be tooled as a possible therapeutic option in HE in ALF.Graphical abstract The possible ULI mediated protection in TAA-induced HE rat model.
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Affiliation(s)
- Rehab E Abo El Gheit
- Physiology Department, Faculty of Medicine, Tanta University, El Geesh Street, Tanta, Egypt.
| | - Marwa Mohamed Atef
- Medical Biochemistry Department, Faculty of Medicine, Tanta University, Tanta, Egypt
| | - Ghada A Badawi
- Pharmacology and Toxicology Department, Faculty of Pharmacy and Pharmaceutical Industries, Sinai University, El-Arish, Egypt
| | - Walaa M Elwan
- Histology Department, Faculty of Medicine, Tanta University, Tanta, Egypt
| | - H A Alshenawy
- Pathology Department, Faculty of Medicine, Tanta University, Tanta, Egypt
| | - Marwa Nagy Emam
- Physiology Department, Faculty of Medicine, Tanta University, El Geesh Street, Tanta, Egypt
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Panda S, Sikdar M, Biswas S, Sharma R, Kar A. Allylpyrocatechol, isolated from betel leaf ameliorates thyrotoxicosis in rats by altering thyroid peroxidase and thyrotropin receptors. Sci Rep 2019; 9:12276. [PMID: 31439949 PMCID: PMC6706422 DOI: 10.1038/s41598-019-48653-9] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2018] [Accepted: 08/08/2019] [Indexed: 01/10/2023] Open
Abstract
Allylpyrocatechol (APC) was isolated from betel leaf and its possible role in L-thyroxin (L-T4)-induced thyrotoxic rats was evaluated. The disease condition, thyrotoxicosis was confirmed by higher levels of thyroid hormones and low thyrotropin (TSH) in serum. Increased hepatic activities of 5'-mono-deiodinase(5'D1), glucose-6-phospatase (G-6-Pase); serum concentrations of alanine transaminase (ALT), aspartate aminotransferase (AST), lactate dehydrogenase(LDH) and tumour necrosis factor-alpha(TNF-α) were observed in thyrotoxic rats. Hepatic lipid peroxidation(LPO) was also increased and the endogenous antioxidants were depleted in these rats. In western blot analysis thyroid peroxidase expression was found to be reduced, whereas thyrotropin receptor(TSHR) expression was enhanced in thyroid gland of these animals. On the other hand, APC treatment in thyrotoxic rats decreased the levels of serum thyroid hormones, ALT, AST, TNF-α and LDH, as well as hepatic 5' D1 and G-6-Pase activities. However, it increased the serum TSH levels. APC also reduced the hepatic LPO and increased the cellular antioxidants in thyrotoxic rats. However, expression of TSHR was inhibited and TPO was increased by APC. The test compound also improved histological features in both liver and thyroid. Present report appears to be the first one that indicates the positive role of APC in ameliorating T4-induced thyrotoxicosis.
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Affiliation(s)
- Sunanda Panda
- School of Pharmacy, Devi Ahilya University, Indore, India.
| | - Malabika Sikdar
- Department of Zoology, Dr. Hari Singh Gour Vishwavidyalaya, Saugar, India
| | - Sagarika Biswas
- Department of Genomics and Molecular Medicine, CSIR-Institute of Genomics and Integrative Biology, New Delhi, India
| | - Rajesh Sharma
- School of Pharmacy, Devi Ahilya University, Indore, India
| | - Anand Kar
- Thyroid Research laboratory, School of Life Sciences, Devi Ahilya University, Indore, India
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El Moussawi L, Chakkour M, Kreydiyyeh S. The epinephrine-induced PGE2 reduces Na+/K+ ATPase activity in Caco-2 cells via PKC, NF-κB and NO. PLoS One 2019; 14:e0220987. [PMID: 31393950 PMCID: PMC6687175 DOI: 10.1371/journal.pone.0220987] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2019] [Accepted: 07/26/2019] [Indexed: 12/03/2022] Open
Abstract
We showed previously an epinephrine-induced inhibition of the Na+/K+ ATPase in Caco-2 cells mediated via PGE2. This work is an attempt to further elucidate mediators downstream of PGE2 and involved in the observed inhibitory effect. The activity of the Na+/K+ ATPase was assayed by measuring the amount of inorganic phosphate liberated in presence and absence of ouabain, a specific inhibitor of the enzyme. Changes in the protein expression of the Na+/K+ ATPase were investigated by western blot analysis which revealed a significant decrease in the abundance of the ATPase in plasma membranes. Treating the cells with epinephrine or PGE2 in presence of SC19220, a blocker of EP1 receptors abolished completely the effect of the hormone and the prostaglandin while the effect was maintained unaltered in presence of antagonists to all other receptors. Treatment with calphostin C, PTIO, ODQ or KT5823, respective inhibitors of PKC, NO, soluble guanylate cyclase and PKG, abrogated completely the effect of epinephrine and PGE2, suggesting an involvement of these mediators. A significant inhibition of the ATPase was observed when cells were treated with PMA, an activator of PKC or with 8-Br-cGMP, a cell permeable cGMP analogue. PMA did reduce the protein expression of IκB, as shown by western blot analysis, and its effect on the ATPase was not manifested in presence of an inhibitor of NF-κB while that of SNAP, a nitric oxide donor, was not affected. The results infer that NF-κB is downstream PKC and upstream NO. The data support a pathway in which epinephrine induces the production of PGE2 which binds to EP1 receptors and activates PKC and NF-κB leading to NO synthesis. The latter activates soluble guanylate cyclase resulting in cGMP production and activation of PKG which through direct or indirect phosphorylation inhibits the Na+/K+ ATPase by inducing its internalization.
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Affiliation(s)
- Layla El Moussawi
- Department of Biology, Faculty of Arts & Sciences, American University of Beirut, Beirut, Lebanon
| | - Mohamed Chakkour
- Department of Biology, Faculty of Arts & Sciences, American University of Beirut, Beirut, Lebanon
| | - Sawsan Kreydiyyeh
- Department of Biology, Faculty of Arts & Sciences, American University of Beirut, Beirut, Lebanon
- * E-mail:
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Panda S, Sharma R, Kar A. Chavibetol corrects thyrotoxicosis through alterations in thyroid peroxidase. Naunyn Schmiedebergs Arch Pharmacol 2019; 392:541-550. [PMID: 30610248 DOI: 10.1007/s00210-018-01606-x] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2018] [Accepted: 12/14/2018] [Indexed: 12/12/2022]
Abstract
Thyrotoxicosis is a clinical syndrome that commonly results from excess secretion and/or release of thyroid hormones in the circulation. It affects most of the body systems and if not treated properly may lead to serious health problems. In this investigation, we isolated a phenolic compound, chavibetol (CHV) from Piper betel leaf and evaluated its possible ameliorative effects in thyrotoxicosis of rats. Adult female rats were rendered thyrotoxic by the administration of L-thyroxine (L-T4) at 500 μg/kg/day, i.p., for 12 days, and then chavibetol (20.0 mg/kg, p.o.) was administered for 2 weeks. L-T4 administration elevated the concentration of serum thyroxine and triiodothyronine, activities of alanineaminotransferase and aspartate aminotransferase, and decreased the thyrotropin level as well as the expression of thyroid peroxidase (TPO). Further, it increased the activities of hepatic 5'mono-deiodinase-I, glucose-6--phosphatase, sodium-potasium-ATPase, and lipid peroxidation, and depleted the cellular antioxidants. However, chavibetol treatment to thyrotoxic rats normalized almost all these indices including TPO and also preserved the integrity of thyroid tissues suggesting its potential to correct thyrotoxicosis. Effects of CHV were more or less similar to a conventional antithyroid drug, propylthiouracil (PTU).
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Affiliation(s)
- Sunanda Panda
- School of Pharmacy, Devi Ahilya University, Indore, India.
| | - Rajesh Sharma
- School of Pharmacy, Devi Ahilya University, Indore, India
| | - Anand Kar
- School of Life Sciences, Devi Ahilya University, Indore, India
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Rida R, Kreydiyyeh S. FTY720P inhibits the Na +/K + ATPase in Caco-2 cells via S1PR2: PGE2 and NO are along the signaling pathway. Life Sci 2018; 215:198-206. [PMID: 30439376 DOI: 10.1016/j.lfs.2018.11.026] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2018] [Revised: 11/10/2018] [Accepted: 11/11/2018] [Indexed: 01/08/2023]
Abstract
AIMS Sphingosine-1-phosphate (S1P) has been implicated lately in inflammatory bowel disease which has diarrhea as one of its symptoms. Diarrhea is due to altered water movements as a result of altered electrolyte transport, and in particular sodium. Sodium movements are geared by the sodium gradient established by the Na+/K+ ATPase. The aim of this work was to investigate if S1P can modulate the activity of the ATPase, using Caco-2 cells as a model and the S1P analogue, FTY720P. MATERIALS AND METHODS The activity of the ATPase was assayed by measuring the amount of inorganic phosphate liberated in presence and absence of ouabain. Protein expression of the various S1P receptors was studied by western blot analysis. KEY FINDINGS Caco-2 cells were found to express mainly S1PR2 and S1PR3. FTY720P (7.5 nM) reduced significantly the activity of the Na+/K+ ATPase when applied for 15 min. This inhibitory effect disappeared in presence of JTE-013, a specific blocker of S1PR2, and indomethacin, an inhibitor of cyclooxygenase enzymes, and was mimicked by CYM5520, a S1PR2 agonist and by exogenous PGE2. The inhibitory effect of PGE2 did not appear when EP3 receptors were blocked or when a nitric oxide scavenger was added. RpcAMP, a PKA inhibitor, reduced the activity of the Na+/K+ ATPase, while dbcAMP, a PKA activator was without any effect and when added, abrogated the effect of PGE2. SIGNIFICANCE It was concluded that FTY720P inhibits the Na+/K+ ATPase via activation of S1PR2 and generation of PGE2 nitric oxide.
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Affiliation(s)
- Reem Rida
- Department of Biology, Faculty of Arts & Sciences, American University of Beirut, Beirut, Lebanon
| | - Sawsan Kreydiyyeh
- Department of Biology, Faculty of Arts & Sciences, American University of Beirut, Beirut, Lebanon.
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Anti-Breast Cancer Activity of Latroeggtoxin-V Mined from the Transcriptome of Spider Latrodectus tredecimguttatus Eggs. Toxins (Basel) 2018; 10:toxins10110451. [PMID: 30400202 PMCID: PMC6266733 DOI: 10.3390/toxins10110451] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2018] [Revised: 10/27/2018] [Accepted: 10/31/2018] [Indexed: 01/08/2023] Open
Abstract
As a black widow spider, Latrodectus tredecimguttatus has poisonous components not only in venomous glands but also in eggs. Our previous work had carried out a transcriptome analysis of the spider eggs in an attempt to probe into the molecular basis of the egg toxicity. A proteinaceous toxin, named Latroeggtoxin-V, was mined from the identified transcriptome. In this study, the gene of Latroeggtoxin-V was cloned and heterologously expressed, and the anticancer activity of the recombinant Latroeggtoxin-V (rLatroeggtoxin-V) was characterized. Activity assay found that rLatroeggtoxin-V could selectively act on breast cancer line MDA-MB-231 cells, not only arresting their cell cycle, inhibiting their proliferation and migration, but also inducing their apoptosis. Bioinformatics analysis suggested that Latroeggtoxin-V belongs to the ATPase inhibitor protein family and the further activity assay showed that the rLatroeggtoxin-V inhibited the activity of the Na+/K+-ATPase in MDA-MB-231 cells in a concentration-dependent manner, suggesting that the anticancer activity of Latroeggtoxin-V is based on its affecting the ion transport and receptor functions of Na+/K+-ATPase. The present work not only laid the foundation for the utilization of Latroeggtoxin-V in the anticancer drug development and the related fields, but also provided a new paradigm for exploration of the proteinaceous toxins under the direction of transcriptomics and bioinformatics.
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Novaes LS, dos Santos NB, Dragunas G, Perfetto JG, Leza JC, Scavone C, Munhoz CD. Repeated Restraint Stress Decreases Na,K-ATPase Activity via Oxidative and Nitrosative Damage in the Frontal Cortex of Rats. Neuroscience 2018; 393:273-283. [DOI: 10.1016/j.neuroscience.2018.09.037] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2018] [Revised: 09/23/2018] [Accepted: 09/26/2018] [Indexed: 12/23/2022]
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Fernandes FA, Dutra BK, Mosele F, Araujo ASR, Ferreira GD, Belló-Klein A, Kucharski LC, Vinagre AS, Da Silva RSM. Redox and metabolic strategies developed by anterior and posterior gills of the crab Neohelice granulata after short periods of hypo- or hyper-osmotic stress. THE SCIENCE OF THE TOTAL ENVIRONMENT 2018; 639:457-464. [PMID: 29800839 DOI: 10.1016/j.scitotenv.2018.05.162] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/28/2018] [Revised: 05/11/2018] [Accepted: 05/13/2018] [Indexed: 06/08/2023]
Abstract
The aim of this study was to identify the response pattern of redox balance, Na+/K+ATPase activity and HSP70 expression in the posterior and anterior gills of the crab Neohelice granulata submitted to hypo- or hyper-osmotic stress for 1 h and 6 h. After 1 h of either type of osmotic stress, there was an increase in catalase activity, but a decrease in GSSG/GSH ratio (oxidized to reduced glutathione ratio) and Na+/K+ATPase activity in both gill sets. H2O2 levels decreased only in the posterior gills. H2O2 levels and Na+/K+ATPase activity remained reduced after 6 h of exposure to either type of osmotic stress in both gill sets. The GSSG/GSH ratio returned to initial levels after 6 h of hyper-osmotic stress, whereas it increased 10 times in both gill sets after hypo-osmotic stress. Furthermore, HSP70 protein expression increased in posterior gills after 6 h of hypo-osmotic stress. H2O2 levels in tank water decreased after hypo-osmotic challenge and increased after 6 h of hyper-osmotic stress, indicating increased H2O2 excretion. Therefore, N. granulata gills have redox, metabolic and molecular strategies to deal with rapid osmotic challenges, an important environmental parameter that influences juvenile and adult crab distribution and abundance within different populations.
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Affiliation(s)
- F A Fernandes
- Laboratório de Metabolismo e Endocrinologia Comparada (LAMEC), Departamento de Fisiologia, Institute of Basic Health Sciences (ICBS), Federal University of Rio Grande do Sul (UFRGS), Brazil; Laboratório de Ictiologia, Instituto Federal de Educação, Ciência e Tecnologia Farroupilha - Campus São Vicente do Sul (IFFAR), Brazil
| | - B K Dutra
- Laboratório de Ictiologia, Instituto Federal de Educação, Ciência e Tecnologia Farroupilha - Campus São Vicente do Sul (IFFAR), Brazil
| | - F Mosele
- Laboratório de Fisiologia Cardiovascular, Departamento de Fisiologia, ICBS, UFRGS, Brazil
| | - A S R Araujo
- Laboratório de Fisiologia Cardiovascular, Departamento de Fisiologia, ICBS, UFRGS, Brazil
| | - G D Ferreira
- Departamento de Fisiologia, Federal University of Pelotas (UFPEL), Brazil
| | - A Belló-Klein
- Laboratório de Fisiologia Cardiovascular, Departamento de Fisiologia, ICBS, UFRGS, Brazil
| | - L C Kucharski
- Laboratório de Metabolismo e Endocrinologia Comparada (LAMEC), Departamento de Fisiologia, Institute of Basic Health Sciences (ICBS), Federal University of Rio Grande do Sul (UFRGS), Brazil
| | - A S Vinagre
- Laboratório de Metabolismo e Endocrinologia Comparada (LAMEC), Departamento de Fisiologia, Institute of Basic Health Sciences (ICBS), Federal University of Rio Grande do Sul (UFRGS), Brazil.
| | - R S M Da Silva
- Laboratório de Metabolismo e Endocrinologia Comparada (LAMEC), Departamento de Fisiologia, Institute of Basic Health Sciences (ICBS), Federal University of Rio Grande do Sul (UFRGS), Brazil
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Annonacin promotes selective cancer cell death via NKA-dependent and SERCA-dependent pathways. Cell Death Dis 2018; 9:764. [PMID: 29988040 PMCID: PMC6037677 DOI: 10.1038/s41419-018-0772-x] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2018] [Revised: 05/07/2018] [Accepted: 05/10/2018] [Indexed: 12/30/2022]
Abstract
In the healthcare sector, phytocompounds are known to be beneficial by contributing or alleviating a variety of diseases. Studies have demonstrated the progressive effects of phytocompounds on immune-related diseases and to exhibit anticancer effects. Graviola tree is an evergreen tree with its extracts (leafs and seeds) been reported having anticancer properties, but the precise target of action is not clear. Using an in silico approach, we predicted that annonacin, an Acetogenin, the active agent found in Graviola leaf extract (GLE) to potentially act as a novel inhibitor of both sodium/potassium (NKA) and sarcoplasmic reticulum (SERCA) ATPase pumps. We were able to validate and confirm the in silico studies by showing that GLE inhibited NKA and SERCA activity in intact cells. In the present study, we also demonstrated the antiproliferative and anticancer effects of GLE in a variety of cancer cell lines with limited toxic effects on non-transformed cells. Moreover, our results revealed that known inhibitors of both NKA and SERCA pumps could also promote cell death in several cancer cell lines. In addition, a mouse xenograft cancer model showed GLE as able to reduce tumor size and progression. Finally, bioprofiling studies indicated a strong correlation between overexpression of both NKA and SERCA gene expression vs. survival rates. Overall, our results demonstrated that GLE can promote selective cancer cell death via inhibiting NKA and SERCA, and thus can be considered as a potential novel treatment for cancer. After molecular analysis of GLE by liquid chromatography–mass spectrometry and ESI–QTOF–MS analysis, it was found that the MS spectrum of the high abundant chromatographic peak purified sample highly consisted of annonacin.
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15
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El Moussawi L, Chakkour M, Kreydiyyeh SI. Epinephrine modulates Na+/K+ ATPase activity in Caco-2 cells via Src, p38MAPK, ERK and PGE2. PLoS One 2018; 13:e0193139. [PMID: 29466417 PMCID: PMC5821373 DOI: 10.1371/journal.pone.0193139] [Citation(s) in RCA: 4] [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: 10/30/2017] [Accepted: 02/05/2018] [Indexed: 01/23/2023] Open
Abstract
Epinephrine, a key stress hormone, is known to affect ion transport in the colon. Stress has been associated with alterations in colonic functions leading to changes in water movements manifested as diarrhea or constipation. Colonic water movement is driven by the Na+-gradient created by the Na+/K+-ATPase. Whether epinephrine acts via an effect on the Na+/K+-ATPase hasn’t been studied before. The aim of this work was to investigate the effect of epinephrine on the Na+/K+-ATPase and to elucidate the signaling pathway involved using CaCo-2 cells as a model. The activity of the Na+/K+-ATPase was assayed by measuring the amount of inorganic phosphate released in presence and absence of ouabain, a specific inhibitor of the enzyme. Epinephrine, added for 20 minutes, decreased the activity of the Na+/K+-ATPase by around 50%. This effect was found to be mediated by α2 adrenergic receptors as it was fully abolished in the presence of yohimbine an α2-blocker, but persisted in presence of other adrenergic antagonists. Furthermore, treatment with Rp-cAMP, a PKA inhibitor, mimicked epinephrine’s negative effect and didn’t result in any additional inhibition when both were added simultaneously. Treatment with indomethacin, PP2, SB202190, and PD98059, respective inhibitors of COX enzymes, Src, p38MAPK, and ERK completely abrogated the effect of epinephrine. The effect of epinephrine did not appear also in presence of inhibitors of all four different types of PGE2 receptors. Western blot analysis revealed an epinephrine-induced increase in the phosphorylation of p38 MAPK and ERK that disappeared in presence of respectively PP2 and SB2020190. In addition, an inhibitory effect, similar to that of epinephrine’s, was observed upon incubation with PGE2. It was concluded that epinephrine inhibits the Na+/K+-ATPase by the sequential activation of α2 adrenergic receptors, Src, p38MAPK, and ERK leading to PGE2 release.
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Affiliation(s)
- Layla El Moussawi
- Department of Biology, Faculty of Arts & Sciences, American University of Beirut, Beirut, Lebanon
| | - Mohamed Chakkour
- Department of Biology, Faculty of Arts & Sciences, American University of Beirut, Beirut, Lebanon
| | - Sawsan I. Kreydiyyeh
- Department of Biology, Faculty of Arts & Sciences, American University of Beirut, Beirut, Lebanon
- * E-mail:
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16
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Al Alam N, Kreydiyyeh SI. Signaling pathway involved in the inhibitory effect of FTY720P on the Na +/K + ATPase in HepG2 cells. J Cell Commun Signal 2017; 11:309-316. [PMID: 28197966 PMCID: PMC5704036 DOI: 10.1007/s12079-016-0369-z] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2016] [Accepted: 11/28/2016] [Indexed: 02/05/2023] Open
Abstract
The Na+/K+ ATPase modulates the activity of many transporters in the liver, and maintains the ionic constancy of the intracellular milieu, preserving thus normal functioning of hepatocytes. Previous work showed that FTY720P, a sphingosine one phosphate receptor agonist used in the treatment of multiple sclerosis, exerts in HepG2 cells, an inhibitory effect on the activity of the ATPase, mediated via PGE2. This study is an attempt to identify the signaling molecules involved downstream of the prostaglandin. The activity of the ATPase was assayed by measuring the amount of inorganic phosphate liberated in presence and absence of ouabain, a specific inhibitor of the enzyme. The effect of FTY720P and PGE2 disappeared completely in presence of PF-04418948, a blocker of EP2 receptors, RpcAMP, an inhibitor of PKA, PD98059, an inhibitor of ERK, as well as in presence of PTIO, a nitric oxide synthase inhibitor, but was mimicked by butaprost, an EP2 agonist, dbcAMP, a cell permeable cAMP analogue, and SNAP1,a nitric oxide generator. PGE2 and dbcAMP increased the expression of phosphorylated ERK but not total ERK. This increase did not appear however in presence of PTIO, indicating that PKA is upstream of NO. It was concluded that FTY 720P induces PGE2 release which activates NOS leading to NO production and ERK activation. ERK then inhibits directly or indirectly the Na+/K+ ATPase.
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Affiliation(s)
- Nadine Al Alam
- Department of Biology, Faculty of Arts & Sciences, American University of Beirut, Beirut, Lebanon
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17
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Gable M, Ellis L, Fedorova OV, Bagrov AY, Askari A. Comparison of Digitalis Sensitivities of Na +/K +-ATPases from Human and Pig Kidneys. ACS OMEGA 2017; 2:3610-3615. [PMID: 28782051 PMCID: PMC5537699 DOI: 10.1021/acsomega.7b00591] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/11/2017] [Accepted: 07/06/2017] [Indexed: 05/16/2023]
Abstract
Digitalis drugs are selective inhibitors of the plasma membrane Na+/K+-ATPase. There are many studies on molecular mechanisms of digitalis interaction with purified pig kidney enzyme, with the tacit assumption that it is a good model of human kidney enzyme. However, previous studies on crude or recombinant human kidney enzymes are limited, and have not resulted in consistent findings on their digitalis sensitivities. Hence, we prepared comparably purified enzymes from human and pig kidneys and determined inhibitory constants of digoxin, ouabain, ouabagenin, bufalin, and marinobufagenin (MBG) on enzyme activity under optimal turnover conditions. We found that each compound had the same potency against the two enzymes, indicating that (i) the pig enzyme is an appropriate model of the human enzyme, and (ii) prior discrepant findings on human kidney enzymes were either due to structural differences between the natural and recombinant enzymes or because potencies were determined using binding constants of digitalis for enzymes under nonphysiological conditions. In conjunction with previous findings, our newly determined inhibitory constants of digitalis compounds for human kidney enzymes indicate that (i) of the compounds that have long been advocated to be endogenous hormones, only bufalin and MBG may act as such at kidney tubules, and (ii) beneficial effects of digoxin, the only digitalis with extensive clinical use, does not involve its inhibitory effect on renal tubular Na+/K+-ATPase.
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Affiliation(s)
- Marjorie
E. Gable
- Department
Biochemistry & Cancer Biology, College of Medicine & Life
Sciences, University of Toledo, 3000 Arlington Avenue, MS 1010, Toledo, Ohio 43614, United States
| | - Linda Ellis
- Department
Biochemistry & Cancer Biology, College of Medicine & Life
Sciences, University of Toledo, 3000 Arlington Avenue, MS 1010, Toledo, Ohio 43614, United States
| | - Olga V. Fedorova
- Laboratory
of Cardiovascular Science, National Institute of Aging, National Institutes of Health, Baltimore, Maryland 21224, United States
| | - Alexei Y. Bagrov
- Laboratory
of Cardiovascular Science, National Institute of Aging, National Institutes of Health, Baltimore, Maryland 21224, United States
- Sechenov
Institute of Evolutionary Physiology and Biochemistry, Russian Academy of Sciences, St. Petersburg 194223, Russia
| | - Amir Askari
- Department
Biochemistry & Cancer Biology, College of Medicine & Life
Sciences, University of Toledo, 3000 Arlington Avenue, MS 1010, Toledo, Ohio 43614, United States
- E-mail: . Phone: 419-383-3982
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18
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Abstract
The Na,K-ATPase is a plasma membrane enzyme that catalyzes active ion transport by the hydrolysis of ATP. Its activity in vivo is determined by many factors, particularly the concentration of intracellular sodium ions. It is the target of the cardiac glycoside class of drugs and of endogenous regulators. Its assay is often an endpoint in the investigation of physiological processes, and it is a promising drug target. As described in this unit, its enzymatic activity can be determined in extracts from tissues by test tube assay using a spectrophotometer or (32)P-ATP. The protocols in this chapter measure inorganic phosphate as the end product of hydrolysis of ATP.
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Affiliation(s)
- Kathleen J Sweadner
- Laboratory of Membrane Biology, Massachusetts General Hospital, Edwards 4, 55 Fruit Street, Boston, MA, 02114, USA.
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19
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De Ford C, Calderón C, Sehgal P, Fedosova NU, Murillo R, Olesen C, Nissen P, Møller JV, Merfort I. Discovery of Tricyclic Clerodane Diterpenes as Sarco/Endoplasmic Reticulum Ca(2+)-ATPase Inhibitors and Structure-Activity Relationships. JOURNAL OF NATURAL PRODUCTS 2015; 78:1262-1270. [PMID: 25993619 DOI: 10.1021/acs.jnatprod.5b00062] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Tricyclic clerodane diterpenes (TCDs) are natural compounds that often show potent cytotoxicity for cancer cells, but their mode of action remains elusive. A computationally based similarity search (CDRUG), combined with principal component analysis (ChemGPS-NP) and docking calculations (GOLD 5.2), suggested TCDs to be inhibitors of the sarco/endoplasmic reticulum Ca(2+)-ATPase (SERCA) pump, which is also the target of the sesquiterpene lactone thapsigargin. Biochemical studies were performed with 11 TCDs on purified rabbit skeletal muscle sarcoplasmic reticulum membranes, which are highly enriched with the SERCA1a isoform. Casearborin D (2) exhibited the highest affinity, with a KD value of 2 μM and giving rise to complete inhibition of SERCA1a activity. Structure-activity relationships revealed that functionalization of two acyl side chains (R1 and R4) and the hydrophobicity imparted by the aliphatic chain at C-9, as well as a C-3,C-4 double bond, play crucial roles for inhibitory activity. Docking studies also suggested that hydrophobic interactions in the binding site, especially with Phe256 and Phe834, may be important for a strong inhibitory activity of the TCDs. In conclusion, a novel class of SERCA inhibitory compounds is presented.
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Affiliation(s)
- Christian De Ford
- †Department of Pharmaceutical Biology and Biotechnology, Albert Ludwigs University Freiburg, Stefan-Meier-Strasse 19, 79104 Freiburg, Germany
- ‡Spemann Graduate School of Biology and Medicine (SGBM), Albert Ludwigs University Freiburg, Albertstrasse 19a, 79104 Freiburg, Germany
- §Faculty of Chemistry and Pharmacy, Albert Ludwigs University Freiburg, Albertstrasse 25, 79104 Freiburg, Germany
| | - Carlos Calderón
- #Escuela de Química and CIPRONA, Universidad de Costa Rica, 2060 San José, Costa Rica
| | - Pankaj Sehgal
- ∥Department of Biomedicine, Aarhus University, Ole Worms Allé 3, DK-8000 Aarhus C, Denmark
- ⊥Centre for Membrane Pumps in Cells and Disease (PUMPkin), National Research Foundation, Aarhus, Denmark
| | - Natalya U Fedosova
- ∥Department of Biomedicine, Aarhus University, Ole Worms Allé 3, DK-8000 Aarhus C, Denmark
- ⊥Centre for Membrane Pumps in Cells and Disease (PUMPkin), National Research Foundation, Aarhus, Denmark
| | - Renato Murillo
- #Escuela de Química and CIPRONA, Universidad de Costa Rica, 2060 San José, Costa Rica
| | - Claus Olesen
- ∥Department of Biomedicine, Aarhus University, Ole Worms Allé 3, DK-8000 Aarhus C, Denmark
- ⊥Centre for Membrane Pumps in Cells and Disease (PUMPkin), National Research Foundation, Aarhus, Denmark
| | - Poul Nissen
- ∥Department of Biomedicine, Aarhus University, Ole Worms Allé 3, DK-8000 Aarhus C, Denmark
- ⊥Centre for Membrane Pumps in Cells and Disease (PUMPkin), National Research Foundation, Aarhus, Denmark
| | - Jesper V Møller
- ∥Department of Biomedicine, Aarhus University, Ole Worms Allé 3, DK-8000 Aarhus C, Denmark
- ⊥Centre for Membrane Pumps in Cells and Disease (PUMPkin), National Research Foundation, Aarhus, Denmark
| | - Irmgard Merfort
- †Department of Pharmaceutical Biology and Biotechnology, Albert Ludwigs University Freiburg, Stefan-Meier-Strasse 19, 79104 Freiburg, Germany
- ‡Spemann Graduate School of Biology and Medicine (SGBM), Albert Ludwigs University Freiburg, Albertstrasse 19a, 79104 Freiburg, Germany
- §Faculty of Chemistry and Pharmacy, Albert Ludwigs University Freiburg, Albertstrasse 25, 79104 Freiburg, Germany
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20
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Guzzi R, Bartucci R, Esmann M, Marsh D. Lipid Librations at the Interface with the Na,K-ATPase. Biophys J 2015; 108:2825-32. [PMID: 26083922 DOI: 10.1016/j.bpj.2015.05.004] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2015] [Revised: 04/22/2015] [Accepted: 05/06/2015] [Indexed: 10/23/2022] Open
Abstract
Transitions between conformational substates of membrane proteins can be driven by torsional librations in the protein that may be coupled to librational fluctuations of the lipid chains. Here, librational motion of spin-labeled lipid chains in membranous Na,K-ATPase is investigated by spin-echo electron paramagnetic resonance. Lipids at the protein interface are targeted by using negatively charged spin-labeled fatty acids that display selectivity of interaction with the Na,K-ATPase. Echo-detected electron paramagnetic resonance spectra from native membranes are corrected for the contribution from the bilayer regions of the membrane by using spectra from dispersions of the extracted membrane lipids. Lipid librations at the protein interface have a flat profile with chain position, whereas librational fluctuations of the bilayer lipids increase pronouncedly from C-9 onward, then flatten off toward the terminal methyl end of the chains. This difference is accounted for by increased torsional amplitude at the chain ends in bilayers, while the amplitude remains restricted throughout the chain at the protein interface with a limited lengthening in correlation time. The temperature dependence of chain librations at the protein interface strongly resembles that of the spin-labeled protein side chains, suggesting solvent-mediated transitions in the protein are driven by fluctuations in the lipid environment.
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Affiliation(s)
- Rita Guzzi
- Department of Physics, Molecular Biophysics Laboratory and Consorzio Nazionale Interuniversitario per le Scienze Fisiche della Material Unit, University of Calabria, Ponte P. Bucci, Rende, Italy
| | - Rosa Bartucci
- Department of Physics, Molecular Biophysics Laboratory and Consorzio Nazionale Interuniversitario per le Scienze Fisiche della Material Unit, University of Calabria, Ponte P. Bucci, Rende, Italy
| | - Mikael Esmann
- Department of Biomedicine, Aarhus University, Aarhus, Denmark
| | - Derek Marsh
- Max-Planck-Institut für biophysikalische Chemie, Göttingen, Germany.
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21
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Vasconcelos AR, Kinoshita PF, Yshii LM, Marques Orellana AM, Böhmer AE, de Sá Lima L, Alves R, Andreotti DZ, Marcourakis T, Scavone C, Kawamoto EM. Effects of intermittent fasting on age-related changes on Na,K-ATPase activity and oxidative status induced by lipopolysaccharide in rat hippocampus. Neurobiol Aging 2015; 36:1914-23. [PMID: 25818175 DOI: 10.1016/j.neurobiolaging.2015.02.020] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2014] [Revised: 12/16/2014] [Accepted: 02/05/2015] [Indexed: 01/18/2023]
Abstract
Chronic neuroinflammation is a common characteristic of neurodegenerative diseases, and lipopolysaccharide (LPS) signaling is linked to glutamate-nitric oxide-Na,K-ATPase isoforms pathway in central nervous system (CNS) and also causes neuroinflammation. Intermittent fasting (IF) induces adaptive responses in the brain that can suppress inflammation, but the age-related effect of IF on LPS modulatory influence on nitric oxide-Na,K-ATPase isoforms is unknown. This work compared the effects of LPS on the activity of α1,α2,3 Na,K-ATPase, nitric oxide synthase gene expression and/or activity, cyclic guanosine monophosphate, 3-nitrotyrosine-containing proteins, and levels of thiobarbituric acid-reactive substances in CNS of young and older rats submitted to the IF protocol for 30 days. LPS induced an age-related effect in neuronal nitric oxide synthase activity, cyclic guanosine monophosphate, and levels of thiobarbituric acid-reactive substances in rat hippocampus that was linked to changes in α2,3-Na,K-ATPase activity, 3-nitrotyrosine proteins, and inducible nitric oxide synthase gene expression. IF induced adaptative cellular stress-response signaling pathways reverting LPS effects in rat hippocampus of young and older rats. The results suggest that IF in both ages would reduce the risk for deficits on brain function and neurodegenerative disorders linked to inflammatory response in the CNS.
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Affiliation(s)
- Andrea Rodrigues Vasconcelos
- Molecular Neuropharmacology Laboratory, Department of Pharmacology, Institute of Biomedical Science, University of São Paulo, São Paulo, Brazil
| | - Paula Fernanda Kinoshita
- Molecular Neuropharmacology Laboratory, Department of Pharmacology, Institute of Biomedical Science, University of São Paulo, São Paulo, Brazil
| | - Lidia Mitiko Yshii
- Molecular Neuropharmacology Laboratory, Department of Pharmacology, Institute of Biomedical Science, University of São Paulo, São Paulo, Brazil
| | - Ana Maria Marques Orellana
- Molecular Neuropharmacology Laboratory, Department of Pharmacology, Institute of Biomedical Science, University of São Paulo, São Paulo, Brazil
| | - Ana Elisa Böhmer
- Molecular Neuropharmacology Laboratory, Department of Pharmacology, Institute of Biomedical Science, University of São Paulo, São Paulo, Brazil
| | - Larissa de Sá Lima
- Molecular Neuropharmacology Laboratory, Department of Pharmacology, Institute of Biomedical Science, University of São Paulo, São Paulo, Brazil
| | - Rosana Alves
- Molecular Neuropharmacology Laboratory, Department of Pharmacology, Institute of Biomedical Science, University of São Paulo, São Paulo, Brazil
| | - Diana Zukas Andreotti
- Molecular Neuropharmacology Laboratory, Department of Pharmacology, Institute of Biomedical Science, University of São Paulo, São Paulo, Brazil
| | - Tania Marcourakis
- Department of Clinical and Toxicological Analysis, Faculty of Pharmaceutical Sciences, University of São Paulo, São Paulo, Brazil
| | - Cristoforo Scavone
- Molecular Neuropharmacology Laboratory, Department of Pharmacology, Institute of Biomedical Science, University of São Paulo, São Paulo, Brazil.
| | - Elisa Mitiko Kawamoto
- Molecular Neuropharmacology Laboratory, Department of Pharmacology, Institute of Biomedical Science, University of São Paulo, São Paulo, Brazil
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22
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Bartucci R, Guzzi R, Esmann M, Marsh D. Water penetration profile at the protein-lipid interface in Na,K-ATPase membranes. Biophys J 2015; 107:1375-82. [PMID: 25229145 DOI: 10.1016/j.bpj.2014.07.057] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2014] [Revised: 06/05/2014] [Accepted: 07/30/2014] [Indexed: 11/28/2022] Open
Abstract
The affinity of ionized fatty acids for the Na,K-ATPase is used to determine the transmembrane profile of water penetration at the protein-lipid interface. The standardized intensity of the electron spin echo envelope modulation (ESEEM) from (2)H-hyperfine interaction with D2O is determined for stearic acid, n-SASL, spin-labeled systematically at the C-n atoms throughout the chain. In both native Na,K-ATPase membranes from shark salt gland and bilayers of the extracted membrane lipids, the D2O-ESEEM intensities of fully charged n-SASL decrease progressively with position down the fatty acid chain toward the terminal methyl group. Whereas the D2O intensities decrease sharply at the n = 9 position in the lipid bilayers, a much broader transition region in the range n = 6 to 10 is found with Na,K-ATPase membranes. Correction for the bilayer population in the membranes yields the intrinsic D2O-intensity profile at the protein-lipid interface. For positions at either end of the chains, the D2O concentrations at the protein interface are greater than in the lipid bilayer, and the positional profile is much broader. This reveals the higher polarity, and consequently higher intramembrane water concentration, at the protein-lipid interface. In particular, there is a significant water concentration adjacent to the protein at the membrane midplane, unlike the situation in the bilayer regions of this cholesterol-rich membrane. Experiments with protonated fatty acid and phosphatidylcholine spin labels, both of which have a considerably lower affinity for the Na,K-ATPase, confirm these results.
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Affiliation(s)
- Rosa Bartucci
- Department of Physics, Molecular Biophysics Laboratory and CNISM Unit, University of Calabria, Ponte P. Bucci, Cubo 31C, 87036 Rende (CS), Italy
| | - Rita Guzzi
- Department of Physics, Molecular Biophysics Laboratory and CNISM Unit, University of Calabria, Ponte P. Bucci, Cubo 31C, 87036 Rende (CS), Italy
| | - Mikael Esmann
- Department of Biomedicine, Aarhus University, 8000 Aarhus, Denmark
| | - Derek Marsh
- Max-Planck-Institut für biophysikalische Chemie, 37070 Göttingen, Germany.
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Na,K-ATPase structure/function relationships probed by the denaturant urea. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2015; 1848:1212-23. [PMID: 25687971 DOI: 10.1016/j.bbamem.2015.02.006] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 10/03/2014] [Revised: 02/04/2015] [Accepted: 02/08/2015] [Indexed: 12/11/2022]
Abstract
Urea interacts with the Na,K-ATPase, leading to reversible as well as irreversible inhibition of the hydrolytic activity. The enzyme purified from shark rectal glands is more sensitive to urea than Na,K-ATPase purified from pig kidney. An immediate and reversible inhibition under steady-state conditions of hydrolytic activity at 37°C is demonstrated for the three reactions studied: the overall Na,K-ATPase activity, the Na-ATPase activity observed in the absence of K+ as well as the K+-dependent phosphatase reaction (K-pNPPase) seen in the absence of Na+. Half-maximal inhibition is seen with about 1M urea for shark enzyme and about 2M urea for pig enzyme. In the presence of substrates there is also an irreversible inhibition in addition to the reversible process, and we show that ATP protects against the irreversible inhibition for both the Na,K-ATPase and Na-ATPase reaction, whereas the substrate paranitrophenylphosphate leads to a slight increase in the rate of irreversible inhibition of the K-pNPPase. The rate of the irreversible inactivation in the absence of substrates is much more rapid for shark enzyme than for pig enzyme. The larger number of potentially urea-sensitive hydrogen bonds in shark enzyme compared to pig enzyme suggests that interference with the extensive hydrogen bonding network might account for the higher urea sensitivity of shark enzyme. The reversible inactivation is interpreted in terms of domain interactions and domain accessibilities using as templates the available crystal structures of Na,K-ATPase. It is suggested that a few interdomain hydrogen bonds are those mainly affected by urea during reversible inactivation.
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24
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Kinoshita PF, Yshii LM, Vasconcelos AR, Orellana AMM, Lima LDS, Davel APC, Rossoni LV, Kawamoto EM, Scavone C. Signaling function of Na,K-ATPase induced by ouabain against LPS as an inflammation model in hippocampus. J Neuroinflammation 2014; 11:218. [PMID: 25551197 PMCID: PMC4307894 DOI: 10.1186/s12974-014-0218-z] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2014] [Accepted: 12/08/2014] [Indexed: 12/26/2022] Open
Abstract
BACKGROUND Ouabain (OUA) is a newly recognized hormone that is synthesized in the adrenal cortex and hypothalamus. Low doses of OUA can activate a signaling pathway by interaction with Na,K-ATPase, which is protective against a number of insults. OUA has central and peripheral anti-inflammatory effects. Lipopolysaccharide (LPS), via toll-like receptor 4 activation, is a widely used model to induce systemic inflammation. This study used a low OUA dose to evaluate its effects on inflammation induced by LPS injection in rats. METHODS Adult male Wistar rats received acute intraperitoneal (ip) OUA (1.8 μg/kg) or saline 20 minutes before LPS (200 μg/kg, ip) or saline injection. Some of the animals had their femoral artery catheterized in order to assess arterial blood pressure values before and after OUA administration. Na,K-ATPase activity, cytokine mRNA levels, apoptosis-related proteins, NF-κB activation brain-derived neurotrophic factor BDNF, corticosterone and TNF-α levels were measured. RESULTS OUA pretreatment decreased mRNA levels of the pro-inflammatory cytokines, inducible nitric oxide synthase (iNOS) and IL-1β, which are activated by LPS in the hippocampus, but with no effect on serum measures of these factors. None of these OUA effects were linked to Na,K-ATPase activity. The involvement of the inflammatory transcription factor NF-κB in the OUA effect was indicated by its prevention of LPS-induced nuclear translocation of the NF-κB subunit, RELA (p65), as well as the decreased cytosol levels of the NF-κB inhibitor, IKB, in the hippocampus. OUA pretreatment reversed the LPS-induced glial fibrillary acidic protein (GFAP) activation and associated inflammation in the dentate gyrus. OUA also prevented LPS-induced increases in the hippocampal Bax/Bcl2 ratio suggesting an anti-apoptotic action in the brain. CONCLUSION Our results suggest that a low dose of OUA has an important anti-inflammatory effect in the rat hippocampus. This effect was associated with decreased GFAP induction by LPS in the dentate gyrus, a brain area linked to adult neurogenesis.
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Affiliation(s)
- Paula Fernanda Kinoshita
- Molecular Neuropharmacology Laboratory, Department of Pharmacology, Institute of Biomedical Science, University of São Paulo, 05508-900, São Paulo, Brazil.
| | - Lidia Mitiko Yshii
- Molecular Neuropharmacology Laboratory, Department of Pharmacology, Institute of Biomedical Science, University of São Paulo, 05508-900, São Paulo, Brazil.
| | - Andrea Rodrigues Vasconcelos
- Molecular Neuropharmacology Laboratory, Department of Pharmacology, Institute of Biomedical Science, University of São Paulo, 05508-900, São Paulo, Brazil.
| | - Ana Maria Marques Orellana
- Molecular Neuropharmacology Laboratory, Department of Pharmacology, Institute of Biomedical Science, University of São Paulo, 05508-900, São Paulo, Brazil.
| | - Larissa de Sá Lima
- Molecular Neuropharmacology Laboratory, Department of Pharmacology, Institute of Biomedical Science, University of São Paulo, 05508-900, São Paulo, Brazil.
| | - Ana Paula Couto Davel
- Department of Physiology and Biophysics, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil.
| | - Luciana Venturini Rossoni
- Department of Physiology and Biophysics, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil.
| | - Elisa Mitiko Kawamoto
- Molecular Neuropharmacology Laboratory, Department of Pharmacology, Institute of Biomedical Science, University of São Paulo, 05508-900, São Paulo, Brazil.
| | - Cristoforo Scavone
- Molecular Neuropharmacology Laboratory, Department of Pharmacology, Institute of Biomedical Science, University of São Paulo, 05508-900, São Paulo, Brazil.
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El-Zein O, Usta J, El Moussawi L, Kreydiyyeh SI. Leptin inhibits the Na(+)/K(+) ATPase in Caco-2 cells via PKC and p38MAPK. Cell Signal 2014; 27:416-23. [PMID: 25499980 DOI: 10.1016/j.cellsig.2014.12.004] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2014] [Revised: 11/22/2014] [Accepted: 12/06/2014] [Indexed: 10/24/2022]
Abstract
We demonstrated previously an inhibitory effect of luminal leptin on glucose absorption in differentiated Caco-2 cells. Since this process is dependent on the Na(+) gradient established by the Na(+)/K(+)ATPase this work was undertaken to investigate if the ATPase is one of the hormone's targets. Fully differentiated Caco-2 cells were incubated with 10nM luminal leptin and the activity of the Na(+)/K(+) ATPase was assayed by measuring the amount of inorganic phosphate liberated. To elucidate the signaling pathway involved, the suspected mediators, namely PKC, p38MAPK, ERK and PI3K, were inhibited with specific pharmacological inhibitors and their implication was confirmed by determining changes in the protein expression of their active phosphorylated forms by Western blot analysis. Leptin reduced significantly the activity of the Na(+)/K(+) ATPase, by activating p38MAPK via inhibition of PKC, an upstream inhibitor of the kinase. ERK and PI3K are modulators of the pump and are not along the pathway activated by leptin but cross talk with it at the level of p38MAPK.
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Affiliation(s)
- Ola El-Zein
- Department of Biology, Faculty of Arts & Sciences, American University of Beirut, Beirut, Lebanon
| | - Julnar Usta
- Department of Biochemistry & Molecular Genetics, Faculty of Medicine, American University of Beirut, Beirut, Lebanon
| | - Layla El Moussawi
- Department of Biology, Faculty of Arts & Sciences, American University of Beirut, Beirut, Lebanon
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Kage H, Flodby P, Gao D, Kim YH, Marconett CN, DeMaio L, Kim KJ, Crandall ED, Borok Z. Claudin 4 knockout mice: normal physiological phenotype with increased susceptibility to lung injury. Am J Physiol Lung Cell Mol Physiol 2014; 307:L524-36. [PMID: 25106430 DOI: 10.1152/ajplung.00077.2014] [Citation(s) in RCA: 60] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
Claudins are tight junction proteins that regulate paracellular ion permeability of epithelium and endothelium. Claudin 4 has been reported to function as a paracellular sodium barrier and is one of three major claudins expressed in lung alveolar epithelial cells (AEC). To directly assess the role of claudin 4 in regulation of alveolar epithelial barrier function and fluid homeostasis in vivo, we generated claudin 4 knockout (Cldn4 KO) mice. Unexpectedly, Cldn4 KO mice exhibited normal physiological phenotype although increased permeability to 5-carboxyfluorescein and decreased alveolar fluid clearance were noted. Cldn4 KO AEC monolayers exhibited unchanged ion permeability, higher solute permeability, and lower short-circuit current compared with monolayers from wild-type mice. Claudin 3 and 18 expression was similar between wild-type and Cldn4 KO alveolar epithelial type II cells. In response to either ventilator-induced lung injury or hyperoxia, claudin 4 expression was markedly upregulated in wild-type mice, whereas Cldn4 KO mice showed greater degrees of lung injury. RNA sequencing, in conjunction with differential expression and upstream analysis after ventilator-induced lung injury, suggested Egr1, Tnf, and Il1b as potential mediators of increased lung injury in Cldn4 KO mice. These results demonstrate that claudin 4 has little effect on normal lung physiology but may function to protect against acute lung injury.
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Affiliation(s)
- Hidenori Kage
- Will Rogers Institute Pulmonary Research Center, Division of Pulmonary, Critical Care, and Sleep Medicine, Department of Medicine
| | - Per Flodby
- Will Rogers Institute Pulmonary Research Center, Division of Pulmonary, Critical Care, and Sleep Medicine, Department of Medicine
| | - Danping Gao
- Will Rogers Institute Pulmonary Research Center, Division of Pulmonary, Critical Care, and Sleep Medicine, Department of Medicine
| | - Yong Ho Kim
- Will Rogers Institute Pulmonary Research Center, Division of Pulmonary, Critical Care, and Sleep Medicine, Department of Medicine
| | - Crystal N Marconett
- Departments of Surgery and Biochemistry and Molecular Biology, Norris Comprehensive Cancer Center
| | - Lucas DeMaio
- Will Rogers Institute Pulmonary Research Center, Division of Pulmonary, Critical Care, and Sleep Medicine, Department of Medicine
| | - Kwang-Jin Kim
- Will Rogers Institute Pulmonary Research Center, Division of Pulmonary, Critical Care, and Sleep Medicine, Department of Medicine, Departments of Physiology and Biophysics and Department of Pharmacology and Pharmaceutical Sciences, School of Pharmacy, University of Southern California; Department of Biomedical Engineering and
| | - Edward D Crandall
- Will Rogers Institute Pulmonary Research Center, Division of Pulmonary, Critical Care, and Sleep Medicine, Department of Medicine, Pathology, Keck School of Medicine, University of Southern California; Mork Family Department of Chemical Engineering and Materials Science, Viterbi School of Engineering, University of Southern California, Los Angeles, California
| | - Zea Borok
- Will Rogers Institute Pulmonary Research Center, Division of Pulmonary, Critical Care, and Sleep Medicine, Department of Medicine, Biochemistry and Molecular Biology, Norris Comprehensive Cancer Center,
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27
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Liu NK, Deng LX, Zhang YP, Lu QB, Wang XF, Hu JG, Oakes E, Bonventre JV, Shields CB, Xu XM. Cytosolic phospholipase A2 protein as a novel therapeutic target for spinal cord injury. Ann Neurol 2014; 75:644-58. [PMID: 24623140 PMCID: PMC4320750 DOI: 10.1002/ana.24134] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2013] [Revised: 02/28/2014] [Accepted: 03/10/2014] [Indexed: 12/17/2022]
Abstract
Objective The objective of this study was to investigate whether cytosolic phospholipase A2 (cPLA2), an important isoform of PLA2 that mediates the release of arachidonic acid, plays a role in the pathogenesis of spinal cord injury (SCI). Methods A combination of molecular, histological, immunohistochemical, and behavioral assessments were used to test whether blocking cPLA2 activation pharmacologically or genetically reduced cell death, protected spinal cord tissue, and improved behavioral recovery after a contusive SCI performed at the 10th thoracic level in adult mice. Results SCI significantly increased cPLA2 expression and activation. Activated cPLA2 was localized mainly in neurons and oligodendrocytes. Notably, the SCI-induced cPLA2 activation was mediated by the extracellular signal-regulated kinase signaling pathway. In vitro, activation of cPLA2 by ceramide-1-phosphate or A23187 induced spinal neuronal death, which was substantially reversed by arachidonyl trifluoromethyl ketone, a cPLA2 inhibitor. Remarkably, blocking cPLA2 pharmacologically at 30 minutes postinjury or genetically deleting cPLA2 in mice ameliorated motor deficits, and reduced cell loss and tissue damage after SCI. Interpretation cPLA2 may play a key role in the pathogenesis of SCI, at least in the C57BL/6 mouse, and as such could be an attractive therapeutic target for ameliorating secondary tissue damage and promoting recovery of function after SCI.
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Affiliation(s)
- Nai-Kui Liu
- Spinal Cord and Brain Injury Research Group, Stark Neurosciences Research Institute, Department of Neurological Surgery, and Goodman Campbell Brain and Spine, Indiana University School of Medicine, Indianapolis, IN
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28
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Gable ME, Abdallah SL, Najjar SM, Liu L, Askari A. Digitalis-induced cell signaling by the sodium pump: on the relation of Src to Na(+)/K(+)-ATPase. Biochem Biophys Res Commun 2014; 446:1151-4. [PMID: 24667596 DOI: 10.1016/j.bbrc.2014.03.071] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2014] [Accepted: 03/17/2014] [Indexed: 11/15/2022]
Abstract
In addition to performing its essential transport function, the sodium pump also activates multiple cell signaling pathways in response to digitalis drugs such as ouabain. Based mainly on cell-free studies with mixtures of purified Src kinase and Na(+)/K(+)-ATPase, a well-advocated hypothesis on how ouabain initiates the activation of signaling pathways is that there is a preexisting physiological complex of inactive Src bound to the α-subunit of Na(+)/K(+)-ATPase, and that ouabain binding to this subunit disrupts the bound Src and activates it. Because of the published disagreements of the results of such cell-free experiments of two other laboratories, our aim was to attempt the resolution of these discrepancies. We reexamined the effects of ouabain, vanadate, and oligomycin on mixtures of Src, Na(+)/K(+)-ATPase, Mg(2+), and ATP as specified in prior studies; and assayed for Src-418 autophosphorylation as the measure of Src activation. In contrast to the findings of the proponents of the above hypothesis, our results showed similar effects of the three inhibitors of Na(+)/K(+)-ATPase; indicating that Src activation in such experiments is primarily due to the ATP-sparing effect of the ATPase inhibitor on the mixture of two enzymes competing for ATP. We conclude that there is no solid evidence for direct molecular interaction of Src with Na(+)/K(+)-ATPase under physiological conditions.
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Affiliation(s)
- Marjorie E Gable
- Department of Biochemistry and Cancer Biology, College of Medicine and Life Sciences, University of Toledo, Health Science Campus, Toledo, OH 43614, USA
| | - Simon L Abdallah
- Department of Physiology and Pharmacology and the Center for Diabetes and Endocrine Research, University of Toledo, Health Science Campus, Toledo, OH 43614, USA
| | - Sonia M Najjar
- Department of Physiology and Pharmacology and the Center for Diabetes and Endocrine Research, University of Toledo, Health Science Campus, Toledo, OH 43614, USA
| | - Lijun Liu
- Department of Biochemistry and Cancer Biology, College of Medicine and Life Sciences, University of Toledo, Health Science Campus, Toledo, OH 43614, USA
| | - Amir Askari
- Department of Biochemistry and Cancer Biology, College of Medicine and Life Sciences, University of Toledo, Health Science Campus, Toledo, OH 43614, USA.
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29
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Giusto A, Ferrari L. Biochemical responses of ecological importance in males of the austral South America amphipod Hyalella curvispina Shoemaker, 1942 exposed to waterborne cadmium and copper. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2014; 100:193-200. [PMID: 24325969 DOI: 10.1016/j.ecoenv.2013.11.001] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/21/2013] [Revised: 10/09/2013] [Accepted: 11/04/2013] [Indexed: 06/03/2023]
Abstract
The use of physiological parameters as sensitive indicators of toxic stress from exposure to different pollutants is an important issue to be studied. Hyalella curvispina is a Neotropical amphipod often used in ecotoxicological evaluations. This work aimed to quantify biochemical responses of ecological importance in H. curvispina males under stress exposure to sublethal concentrations of waterborne copper (Cu) and cadmium (Cd); in order to obtain basic physiological data as indicators of early effect on this species, on track to its standardization. In order to evaluate the physiological, biochemical and energetic status of the exposed animals, the following endpoints were selected: content of glycogen, total proteins, total lipids, triglycerides, glycerol, arginine, arginine phosphate, levels of lipid peroxidation (TBARS), and Na(+)/K(+)ATPase, catalase (CAT) and superoxide dismutase (SOD) activities. Our results show that the concentrations of Cu (135 and 175 µg/L) and Cd (6.5 and 10.5 µg/L) tested altered most of the biochemical variables measured (glycogen, total proteins, total lipids, triglycerides, arginine phosphate, TBARS, and SOD and Na(+)/K(+)ATPase activities). In addition, neither the levels of glycerol and arginine nor CAT activity were affected by exposure to either metal. Energy metabolism was similarly affected both by exposure to Cu and exposure to Cd. The results obtained show the existence of an energy imbalance associated with oxidative damage, suggesting a comprehensive response. This work represents a first contribution of the evaluation of the effect of two heavy metals in some parameters of oxidative stress and energy metabolism of H. curvispina males. The results indicate these parameters can provide a sensitive criterion for the assessment of early ecotoxicological effects of Cu and Cd in laboratory assays, on a native species representative of the zoobenthic and epiphytic communities of South America.
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Affiliation(s)
- Anabella Giusto
- Applied Ecophysiology Program, Basic Sciences Department, Institute of Ecology and Sustainable Development (INEDES), National University of Luján, mailbox 221, B6700ZBA Luján, Argentina
| | - Lucrecia Ferrari
- Applied Ecophysiology Program, Basic Sciences Department, Institute of Ecology and Sustainable Development (INEDES), National University of Luján, mailbox 221, B6700ZBA Luján, Argentina; Scientific Research Commission (CIC), La Plata, Buenos Aires, Argentina.
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30
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Zhang RR, Tian HY, Tan YF, Chung TY, Sun XH, Xia X, Ye WC, Middleton DA, Fedosova N, Esmann M, Tzen JTC, Jiang RW. Structures, chemotaxonomic significance, cytotoxic and Na+,K+-ATPase inhibitory activities of new cardenolides from Asclepias curassavica. Org Biomol Chem 2014; 12:8919-29. [DOI: 10.1039/c4ob01545b] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
New cardenolides with potent cytotoxic and Na+,K+-ATPase inhibitory activities were isolated from the ornamental milkweed Asclepias curassavica.
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Affiliation(s)
- Rong-Rong Zhang
- Institute of Traditional Chinese Medicine and Natural Products
- College of Pharmacy
- Jinan University
- Guangzhou 510632, P. R. China
| | - Hai-Yan Tian
- Institute of Traditional Chinese Medicine and Natural Products
- College of Pharmacy
- Jinan University
- Guangzhou 510632, P. R. China
| | - Ya-Fang Tan
- Institute of Traditional Chinese Medicine and Natural Products
- College of Pharmacy
- Jinan University
- Guangzhou 510632, P. R. China
| | - Tse-Yu Chung
- Graduate Institute of Biotechnology
- National Chung-Hsing University
- Taichung 40227, China
| | - Xiao-Hui Sun
- Institute of Traditional Chinese Medicine and Natural Products
- College of Pharmacy
- Jinan University
- Guangzhou 510632, P. R. China
| | - Xue Xia
- Institute of Traditional Chinese Medicine and Natural Products
- College of Pharmacy
- Jinan University
- Guangzhou 510632, P. R. China
| | - Wen-Cai Ye
- Institute of Traditional Chinese Medicine and Natural Products
- College of Pharmacy
- Jinan University
- Guangzhou 510632, P. R. China
| | | | | | - Mikael Esmann
- Department of Biomedicine
- Aarhus University
- Aarhus, Denmark
| | - Jason T. C. Tzen
- Graduate Institute of Biotechnology
- National Chung-Hsing University
- Taichung 40227, China
| | - Ren-Wang Jiang
- Institute of Traditional Chinese Medicine and Natural Products
- College of Pharmacy
- Jinan University
- Guangzhou 510632, P. R. China
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31
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Kim MJ, Hur J, Ham IH, Yang HJ, Kim Y, Park S, Cho YW. Expression and activity of the na-k ATPase in ischemic injury of primary cultured astrocytes. THE KOREAN JOURNAL OF PHYSIOLOGY & PHARMACOLOGY : OFFICIAL JOURNAL OF THE KOREAN PHYSIOLOGICAL SOCIETY AND THE KOREAN SOCIETY OF PHARMACOLOGY 2013; 17:275-81. [PMID: 23946686 PMCID: PMC3741483 DOI: 10.4196/kjpp.2013.17.4.275] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/06/2013] [Revised: 04/05/2013] [Accepted: 06/05/2013] [Indexed: 11/15/2022]
Abstract
Astrocytes are reported to have critical functions in ischemic brain injury including protective effects against ischemia-induced neuronal dysfunction. Na-K ATPase maintains ionic gradients in astrocytes and is suggested as an indicator of ischemic injury in glial cells. Here, we examined the role of the Na-K ATPase in the pathologic process of ischemic injury of primary cultured astrocytes. Chemical ischemia was induced by sodium azide and glucose deprivation. Lactate dehydrogenase assays showed that the cytotoxic effect of chemical ischemia on astrocytes began to appear at 2 h of ischemia. The expression of Na-K ATPase α1 subunit protein was increased at 2 h of chemical ischemia and was decreased at 6 h of ischemia, whereas the expression of α1 subunit mRNA was not changed by chemical ischemia. Na-K ATPase activity was time-dependently decreased at 1, 3, and 6 h of chemical ischemia, whereas the enzyme activity was temporarily recovered to the control value at 2 h of chemical ischemia. Cytotoxicity at 2 h of chemical ischemia was significantly blocked by reoxygenation for 24 h following ischemia. Reoxygenation following chemical ischemia for 1 h significantly increased the activity of the Na-K ATPase, while reoxygenation following ischemia for 2 h slightly decreased the enzyme activity. These results suggest that the critical time for ischemia-induced cytotoxicity of astrocytes might be 2 h after the initiation of ischemic insult and that the increase in the expression and activity of the Na-K ATPase might play a protective role during ischemic injury of astrocytes.
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Affiliation(s)
- Mi Jung Kim
- Department of Physiology, Biomedical Science Institute and Medical Research Center, School of Medicine, Kyung Hee University, Seoul 130-701, Korea
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Miles AJ, Fedosova NU, Hoffmann SV, Wallace B, Esmann M. Stabilisation of Na,K-ATPase structure by the cardiotonic steroid ouabain. Biochem Biophys Res Commun 2013; 435:300-5. [DOI: 10.1016/j.bbrc.2013.04.021] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2013] [Accepted: 04/14/2013] [Indexed: 10/26/2022]
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Jaber H, Baydoun E, EL-Zein O, Kreydiyyeh SI. Anti-hyperglycemic effect of the aqueous extract of banana infructescence stalks in streptozotocin-induced diabetic rats. PLANT FOODS FOR HUMAN NUTRITION (DORDRECHT, NETHERLANDS) 2013; 68:83-89. [PMID: 23423722 DOI: 10.1007/s11130-013-0341-5] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
Water extract of banana (Musa sapientum) infructescence stalks has been used in folk medicine in the treatment of diabetes mellitus. This work aims at verifying the claimed effect and elucidating its possible mode of action. The extract was given in replacement of drinking water to diabetic rats, and its mechanism of action was studied by investigating its involvement in glucose transport in Caco-2 monolayers, and in rat jejuna using an in situ perfusion technique. Its effect on the Na(+)/K(+) ATPase was studied by measuring the amount of inorganic phosphate liberated. The extract reduced significantly blood glucose levels in diabetic rats and glucose transport across rat jejuna and Caco-2 monolayers, and induced a 50 % decrease in their Na(+)/K(+) ATPase activity. The extract did not induce any further decrease in jejunal glucose uptake in the simultaneous presence of phloridzin and phloretin, respective inhibitors of SGLT1 and GLUT2 transporters nor did it induce a change in the protein expression of SGLT1 and GLUT2. It was concluded that the extract acts by reducing the Na(+)/K(+) ATPase activity of enterocytes and consequently the sodium gradient required for sugar transport by SGLT1, which leads to down-regulation of GLUT2 and contributes to the observed anti-hyperglycemic effect.
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Affiliation(s)
- Hwaida Jaber
- Department of Biology, Faculty of Arts & Sciences, American University of Beirut, Bliss str, Beirut, Lebanon
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34
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Pellegrino R, Martins TL, Pinto CB, Schein V, Kucharski LC, Da Silva RSM. Effect of starvation and refeeding on amino acid metabolism in muscle of crab Neohelice granulata previously fed protein- or carbohydrate-rich diets. Comp Biochem Physiol A Mol Integr Physiol 2013; 164:29-35. [DOI: 10.1016/j.cbpa.2012.08.004] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2011] [Revised: 08/06/2012] [Accepted: 08/07/2012] [Indexed: 11/25/2022]
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35
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Garçon DP, Lucena MN, Pinto MR, Fontes CFL, McNamara JC, Leone FA. Synergistic stimulation by potassium and ammonium of K(+)-phosphatase activity in gill microsomes from the crab Callinectes ornatus acclimated to low salinity: novel property of a primordial pump. Arch Biochem Biophys 2012; 530:55-63. [PMID: 23262318 DOI: 10.1016/j.abb.2012.12.006] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2012] [Revised: 11/28/2012] [Accepted: 12/04/2012] [Indexed: 11/16/2022]
Abstract
We provide an extensive characterization of the modulation by p-nitrophenylphosphate, Mg²⁺, Na⁺, K(+), Rb⁺, NH(4)(+) and pH of gill microsomal K⁺-phosphatase activity in the posterior gills of Callinectes ornatus acclimated to low salinity (21‰). The synergistic stimulation by K⁺ and NH(4)(+) of the K⁺-phosphatase activity is a novel finding, and may constitute a species-specific feature of K(+)/NH(4)(+) interplay that regulates crustacean gill (Na⁺, K⁺)-ATPase activity. p-Nitrophenylphosphate was hydrolyzed at a maximum rate (V) of 69.2 ± 2.8nmolPimin⁻¹mg⁻¹ with K(0.5)=2.3 ± 0.1mmolL(-1), obeying cooperative kinetics (n(H)=1.7). Stimulation by Mg²⁺ (V=70.1 ± 3.0nmolPimin⁻¹mg⁻¹, K(0.5)=0.88 ± 0.04mmolL⁻¹), K⁺ (V=69.6 ± 2.7nmolPimin⁻¹mg⁻¹, K(0.5)=1.60 ± 0.07mmolL⁻¹) and NH(4)(+) (V=90.8 ± 4.0nmolPimin⁻¹mg⁻¹, K(0.5)=9.2 ± 0.3mmol L⁻¹) all displayed site-site interaction kinetics. In the presence of NH(4)(+), enzyme affinity for K⁺ unexpectedly increased by 7-fold, while affinity for NH(4)(+) was 28-fold greater in the presence than absence of K⁺. Ouabain partially inhibited K⁺-phosphatase activity (K(I)=320 ± 14.0μmolL⁻¹), more effectively when NH(4)(+) was present (K(I)=240 ± 12.0μmolL⁻¹). We propose a model for the synergistic stimulation by K⁺ and NH(4)(+) of the K⁺-phosphatase activity of the (Na⁺, K⁺)-ATPase from C. ornatus posterior gill tissue.
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Affiliation(s)
- Daniela P Garçon
- Departamento de Biologia Molecular, Centro de Ciências Exatas e da Natureza, Universidade Federal da Paraíba, Brazil
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36
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Catechin induced modulation in the activities of thyroid hormone synthesizing enzymes leading to hypothyroidism. Mol Cell Biochem 2012; 374:37-48. [DOI: 10.1007/s11010-012-1503-8] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2012] [Accepted: 10/25/2012] [Indexed: 10/27/2022]
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37
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Dach I, Olesen C, Signor L, Nissen P, le Maire M, Møller JV, Ebel C. Active detergent-solubilized H+,K+-ATPase is a monomer. J Biol Chem 2012; 287:41963-78. [PMID: 23055529 DOI: 10.1074/jbc.m112.398768] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
The H(+),K(+)-ATPase pumps protons or hydronium ions and is responsible for the acidification of the gastric fluid. It is made up of an α-catalytic and a β-glycosylated subunit. The relation between cation translocation and the organization of the protein in the membrane are not well understood. We describe here how pure and functionally active pig gastric H(+),K(+)-ATPase with an apparent Stokes radius of 6.3 nm can be obtained after solubilization with the non-ionic detergent C(12)E(8), followed by exchange of C(12)E(8) with Tween 20 on a Superose 6 column. Mass spectroscopy indicates that the β-subunit bears an excess mass of 9 kDa attributable to glycosylation. From chemical analysis, there are 0.25 g of phospholipids and around 0.024 g of cholesterol bound per g of protein. Analytical ultracentrifugation shows one main complex, sedimenting at s(20,)(w) = 7.2 ± 0.1 S, together with minor amounts of irreversibly aggregated material. From these data, a buoyant molecular mass is calculated, corresponding to an H(+),K(+)-ATPase α,β-protomer of 147.3 kDa. Complementary sedimentation velocity with deuterated water gives a picture of an α,β-protomer with 0.9-1.4 g/g of bound detergent and lipids and a reasonable frictional ratio of 1.5, corresponding to a Stokes radius of 7.1 nm. An α(2),β(2) dimer is rejected by the data. Light scattering coupled to gel filtration confirms the monomeric state of solubilized H(+),K(+)-ATPase. Thus, α,β H(+),K(+)-ATPase is active at least in detergent and may plausibly function as a monomer, as has been established for other P-type ATPases, Ca(2+)-ATPase and Na(+),K(+)-ATPase.
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Affiliation(s)
- Ingrid Dach
- Center for Membrane Pumps in Cells and Diseases, Danish Research Foundation, DK-8000 Aarhus, Denmark
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Dakroub Z, Kreydiyyeh SI. Sphingosine-1-phosphate is a mediator of TNF-α action on the Na+/K+ ATPase in HepG2 cells. J Cell Biochem 2012; 113:2077-85. [PMID: 22271589 DOI: 10.1002/jcb.24079] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
We showed previously that TNF-α down-regulates the Na+/K+ ATPase in HepG2 cells. This work was undertaken to study the role of ceramide and its metabolites in TNF-α action. Treating HepG2 cells with the cytokine in presence of an inhibitor of sphingomyelinase, abrogated the effect of TNF-α on the ATPase. To confirm the involvement of ceramide or its metabolites, cells were incubated with exogenous ceramide. Ceramide reduced time-dependently the activity of the ATPase and its effect disappeared in presence of CAY 10466 or SHKI, respective inhibitors of ceramidase and spingosine kinase, suggesting that ceramide acts via sphingosine or sphingosine-1-phosphate (S1P). However, HepG2 cells treated with exogenous sphingosine showed a higher Na+/K+ ATPase activity inferring that S1P is the one responsible for the down-regulatory effect of TNF-α and ceramide. This hypothesis was confirmed by the observed inhibitory effect of exogenous S1P on the pump, which was maintained when JNK and NF-κB were inhibited separately or simultaneously. The concurrent, but not individual inhibition of the kinase and transcription factor in the absence of S1P imitated the effect of S1P. It was concluded that S1P down-regulates the ATPase by inhibiting both JNK and NF-κB. This conclusion was supported by the observed decrease in the phosphorylation of c-jun and the enhanced protein expression of IκB and lower NK-KB activity.
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Affiliation(s)
- Zeina Dakroub
- Department of Biology, Faculty of Arts and Sciences, American University of Beirut, Beirut, Lebanon
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Chandra AK, Goswami H, Sengupta P. Dietary calcium induced cytological and biochemical changes in thyroid. ENVIRONMENTAL TOXICOLOGY AND PHARMACOLOGY 2012; 34:454-465. [PMID: 22789468 DOI: 10.1016/j.etap.2012.06.003] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/02/2012] [Revised: 06/06/2012] [Accepted: 06/18/2012] [Indexed: 06/01/2023]
Abstract
Certain epidemiological studies revealed correlation between hard water consumption (with high calcium) and thyroid size of the population, though the possible alterations in thyroid physiology upon calcium exposure are still inconclusive. Adult male Wistar strain rats were subjected to calcium treatment at the doses of 0.5g%, 1.0g% and 1.5g% calcium chloride (CaCl(2)) for 60 days. The parameters studied were - thyroid gland weight, histopathology, histomorphometry; thyroid peroxidase (TPO), 5'-deiodinase I (DI), sodium-potassium adenosine triphosphatase (Na(+)-K(+)-ATPase) activities; serum total and free thyroxine (tT4, fT4), total and free triiodothyronine (tT3, fT3), thyroid stimulating hormone (TSH) levels. Enlargement of thyroid with hypertrophic and hyperplastic changes, retarded TPO and 5'-DI but enhanced Na(+)-K(+)-ATPase activities, augmented serum total and free T4 and TSH but decreased total and free T3 levels and low T3/T4 ratio (T3:T4) were observed in the treated groups. All these findings indicate development of goitrogenesis upon exposure to excessive dietary calcium.
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Affiliation(s)
- Amar K Chandra
- Endocrinology & Reproductive Physiology Laboratory, Department of Physiology, University of Calcutta, Kolkata, West Bengal, India.
| | - Haimanti Goswami
- Endocrinology & Reproductive Physiology Laboratory, Department of Physiology, University of Calcutta, Kolkata, West Bengal, India.
| | - Pallav Sengupta
- Endocrinology & Reproductive Physiology Laboratory, Department of Physiology, University of Calcutta, Kolkata, West Bengal, India.
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Teo BKK, Goh KJ, Ng ZJ, Koo S, Yim EKF. Functional reconstruction of corneal endothelium using nanotopography for tissue-engineering applications. Acta Biomater 2012; 8:2941-52. [PMID: 22522131 DOI: 10.1016/j.actbio.2012.04.020] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2011] [Revised: 03/25/2012] [Accepted: 04/11/2012] [Indexed: 10/28/2022]
Abstract
Dysfunction in the corneal endothelium, which controls the hydration and transparency of the cornea, is one of the common reasons for transplantation. A tissue-engineered corneal endothelium is of interest for corneal regeneration and for in vitro testing of ocular drugs. In the native environment, corneal endothelial cells interact with the nanotopography of the underlying Descemet's membrane. This study showed that nanotopography enhanced bovine corneal endothelial cell (BCEC) responses, creating a monolayer which resembled the healthy corneal endothelium. Topographies of different geometries were first tested to identify those that would elicit the most significant responses. A BCEC monolayer was then generated on both micro- and nanoscale pillars and wells. The BCEC monolayer cultured on topographies exhibited polygonal geometries with well-developed tight junction proteins. Scanning electron microscopy revealed that cells on pillars showed a higher density of microvilli, which was similar to native corneal endothelium. BCECs on nanopillars displayed a lower coefficient of variation of area (0.31) that was within the range of healthy corneal endothelium. More importantly, a BCEC monolayer cultured on nanopillars also had an enhanced Na(+)/K(+)-ATPase immunofluorescence expression, mRNA upregulation and a higher Na(+)/K(+)-ATPase activity. These results suggest that nanopillar substrate topography may provide relevant topographical cues, which could significantly enhance the formation and function of corneal endothelium.
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41
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Aaltonen N, Lehtonen M, Varonen K, Goterris GA, Laitinen JT. Lipid phosphate phosphatase inhibitors locally amplify lysophosphatidic acid LPA1 receptor signalling in rat brain cryosections without affecting global LPA degradation. BMC Pharmacol 2012; 12:7. [PMID: 22686545 PMCID: PMC3418163 DOI: 10.1186/1471-2210-12-7] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2011] [Accepted: 06/11/2012] [Indexed: 11/10/2022] Open
Abstract
Background Lysophosphatidic acid (LPA) is a signalling phospholipid with multiple biological functions, mainly mediated through specific G protein-coupled receptors. Aberrant LPA signalling is being increasingly implicated in the pathology of common human diseases, such as arteriosclerosis and cancer. The lifetime of the signalling pool of LPA is controlled by the equilibrium between synthesizing and degradative enzymatic activity. In the current study, we have characterized these enzymatic pathways in rat brain by pharmacologically manipulating the enzymatic machinery required for LPA degradation. Results In rat brain cryosections, the lifetime of bioactive LPA was found to be controlled by Mg2+-independent, N-ethylmaleimide-insensitive phosphatase activity, attributed to lipid phosphate phosphatases (LPPs). Pharmacological inhibition of this LPP activity amplified LPA1 receptor signalling, as revealed using functional autoradiography. Although two LPP inhibitors, sodium orthovanadate and propranolol, locally amplified receptor responses, they did not affect global brain LPA phosphatase activity (also attributed to Mg2+-independent, N-ethylmaleimide-insensitive phosphatases), as confirmed by Pi determination and by LC/MS/MS. Interestingly, the phosphate analog, aluminium fluoride (AlFx-) not only irreversibly inhibited LPP activity thereby potentiating LPA1 receptor responses, but also totally prevented LPA degradation, however this latter effect was not essential in order to observe AlFx--dependent potentiation of receptor signalling. Conclusions We conclude that vanadate- and propranolol-sensitive LPP activity locally guards the signalling pool of LPA whereas the majority of brain LPA phosphatase activity is attributed to LPP-like enzymatic activity which, like LPP activity, is sensitive to AlFx- but resistant to the LPP inhibitors, vanadate and propranolol.
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Affiliation(s)
- Niina Aaltonen
- School of Pharmacy, University of Eastern Finland, P,O, Box 1627, 70211, Kuopio, Finland.
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Kawamoto EM, Lima LS, Munhoz CD, Yshii LM, Kinoshita PF, Amara FG, Pestana RRF, Orellana AMM, Cipolla-Neto J, Britto LRG, Avellar MCW, Rossoni LV, Scavone C. Influence of N-methyl-D-aspartate receptors on ouabain activation of nuclear factor-κB in the rat hippocampus. J Neurosci Res 2011; 90:213-28. [PMID: 22006678 DOI: 10.1002/jnr.22745] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2010] [Revised: 06/25/2011] [Accepted: 06/27/2011] [Indexed: 02/06/2023]
Abstract
It has been shown that ouabain (OUA) can activate the Na,K-ATPase complex and mediate intracellular signaling in the central nervous system (CNS). Inflammatory stimulus increases glutamatergic transmission, especially at N-methyl-D-aspartate (NMDA) receptors, which are usually coupled to the activation of nitric oxide synthase (NOS). Nuclear factor-κB (NF-κB) activation modulates the expression of genes involved in development, plasticity, and inflammation. The present work investigated the effects of OUA on NF-κB binding activity in rat hippocampus and the influence of this OUA-Na,K-ATPase signaling cascade in NMDA-mediated NF-κB activation. The findings presented here are the first report indicating that intrahippocampal administration of OUA, in a concentration that did not alter Na,K-ATPase or NOS activity, induced an activation of NF-κB, leading to increases in brain-derived neurotrophic factor (Bdnf), inducible NOS (iNos), tumor necrosis factor-α (Tnf-α), and B-cell leukemia/lymphoma 2 (Bcl2) mRNA levels. This response was not linked to any significant signs of neurodegeneration as showed via Fluoro-Jade B and Nissl stain. Intrahippocampal administration of NMDA induced NF-κB activation and increased NOS and α(2/3) -Na,K-ATPase activities. NMDA treatment further increased OUA-induced NF-κB activation, which was partially blocked by MK-801, an antagonist of NMDA receptor. These results suggest that OUA-induced NF-κB activation is at least in part dependent on Na,K-ATPase modulatory action of NMDA receptor in hippocampus. The interaction of these signaling pathways could be associated with biological mechanisms that may underlie the basal homeostatic state linked to the inflammatory signaling cascade in the brain.
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Affiliation(s)
- E M Kawamoto
- Molecular Neuropharmacology Laboratory, Department of Pharmacology, Institute of Biomedical Science, University of São Paulo, São Paulo, Brazil
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Liu L, Ivanov AV, Gable ME, Jolivel F, Morrill GA, Askari A. Comparative properties of caveolar and noncaveolar preparations of kidney Na+/K+-ATPase. Biochemistry 2011; 50:8664-73. [PMID: 21905705 PMCID: PMC3186040 DOI: 10.1021/bi2009008] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
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To evaluate previously proposed functions of renal caveolar
Na+/K+-ATPase, we modified the standard procedures
for the preparation of the purified membrane-bound kidney enzyme,
separated the caveolar and noncaveolar pools, and compared their properties.
While the subunits of Na+/K+-ATPase (α,β,γ)
constituted most of the protein content of the noncaveolar pool, the
caveolar pool also contained caveolins and major caveolar proteins
annexin-2 tetramer and E-cadherin. Ouabain-sensitive Na+/K+-ATPase activities of the two pools had similar properties
and equal molar activities, indicating that the caveolar enzyme retains
its ion transport function and does not contain nonpumping enzyme.
As minor constituents, both caveolar and noncaveolar pools also contained
Src, EGFR, PI3K, and several other proteins known to be involved in
stimulous-induced signaling by Na+/K+-ATPase,
indicating that signaling function is not limited to the caveolar
pool. Endogenous Src was active in both pools but was not further
activated by ouabain, calling into question direct interaction of
Src with native Na+/K+-ATPase. Chemical cross-linking,
co-immunoprecipitation, and immunodetection studies showed that in
the caveolar pool, caveolin-1 oligomers, annexin-2 tetramers, and
oligomers of the α,β,γ-protomers of Na+/K+-ATPase form a large multiprotein complex. In conjunction
with known roles of E-cadherin and the β-subunit of Na+/K+-ATPase in cell adhesion and noted intercellular β,β-contacts
within the structure of Na+/K+-ATPase, our findings
suggest that interacting caveolar Na+/K+-ATPases
located at renal adherens junctions maintain contact of two adjacent
cells, conduct essential ion pumping, and are capable of locus-specific
signaling in junctional cells.
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Affiliation(s)
- Lijun Liu
- Department of Biochemistry and Cancer Biology, University of Toledo Health Science Campus, Toledo, Ohio 43614, United States
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Miles AJ, Wallace BA, Esmann M. Correlation of structural and functional thermal stability of the integral membrane protein Na,K-ATPase. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2011; 1808:2573-80. [PMID: 21712026 DOI: 10.1016/j.bbamem.2011.06.009] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/13/2011] [Revised: 06/03/2011] [Accepted: 06/14/2011] [Indexed: 10/18/2022]
Abstract
The membrane-bound cation-transporting P-type Na,K-ATPase isolated from pig kidney membranes is much more resistant towards thermal inactivation than the almost identical membrane-bound Na,K-ATPase isolated from shark rectal gland membranes. The loss of enzymatic activity is correlated well with changes in protein structure as determined using synchrotron radiation circular dichroism (SRCD) spectroscopy. The enzymatic activity is lost at a 12°C higher temperature for pig enzyme than for shark enzyme, and the major changes in protein secondary structure also occur at T(m)'s that are ~10-15°C higher for the pig than for the shark enzyme. The temperature optimum for the rate of hydrolysis of ATP is about 42°C for shark and about 57°C for pig, both of which are close to the temperatures for onset of thermal unfolding. These results suggest that the active site region may be amongst the earliest parts of the structure to unfold. Detergent-solubilized Na,K-ATPases from the two sources show the similar differences in thermal stability as the membrane-bound species, but inactivation occurs at a lower temperature for both, and may reflect the stabilizing effect of a bilayer versus a micellar environment.
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Affiliation(s)
- Andrew J Miles
- Department of Crystallography, Birkbeck College, University of London, London WC1E 7HX, UK
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Aldana-Masangkay GI, Rodriguez-Gonzalez A, Lin T, Ikeda AK, Hsieh YT, Kim YM, Lomenick B, Okemoto K, Landaw EM, Wang D, Mazitschek R, Bradner JE, Sakamoto KM. Tubacin suppresses proliferation and induces apoptosis of acute lymphoblastic leukemia cells. Leuk Lymphoma 2011; 52:1544-55. [PMID: 21699378 DOI: 10.3109/10428194.2011.570821] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Over the past decade, histone deacetylase inhibitors have increasingly been used to treat various malignancies. Tubacin (tubulin acetylation inducer) is a small molecule that inhibits histone deacetylase 6 (HDAC6) and induces acetylation of α-tubulin. We observed a higher antiproliferative effect of tubacin in acute lymphoblastic leukemia (ALL) cells than in normal hematopoietic cells. Treatment with tubacin led to the induction of apoptotic pathways in both pre-B and T cell ALL cells at a 50% inhibitory concentration (IC(50)) of low micromolar concentrations. Acetylation of α-tubulin increases within the first 30 min following treatment of ALL cells with tubacin. We also observed an accumulation of polyubiquitinated proteins and poly(ADP-ribose) polymerase (PARP) cleavage. Furthermore, the signaling pathways activated by tubacin appear to be distinct from those observed in multiple myeloma. In this article, we demonstrate that tubacin enhances the effects of chemotherapy to treat primary ALL cells in vitro and in vivo. These results suggest that targeting HDAC6 alone or in combination with chemotherapy could provide a novel approach to treat ALL.
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Guzzi R, Babavali M, Bartucci R, Sportelli L, Esmann M, Marsh D. Spin-echo EPR of Na,K-ATPase unfolding by urea. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2011; 1808:1618-28. [DOI: 10.1016/j.bbamem.2010.11.008] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/24/2010] [Revised: 11/03/2010] [Accepted: 11/03/2010] [Indexed: 11/15/2022]
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Li KC, Zhang FX, Li CL, Wang F, Yu MY, Zhong YQ, Zhang KH, Lu YJ, Wang Q, Ma XL, Yao JR, Wang JY, Lin LB, Han M, Zhang YQ, Kuner R, Xiao HS, Bao L, Gao X, Zhang X. Follistatin-like 1 suppresses sensory afferent transmission by activating Na+,K+-ATPase. Neuron 2011; 69:974-87. [PMID: 21382556 DOI: 10.1016/j.neuron.2011.01.022] [Citation(s) in RCA: 70] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/03/2010] [Indexed: 01/09/2023]
Abstract
Excitatory synaptic transmission is modulated by inhibitory neurotransmitters and neuromodulators. We found that the synaptic transmission of somatic sensory afferents can be rapidly regulated by a presynaptically secreted protein, follistatin-like 1 (FSTL1), which serves as a direct activator of Na(+),K(+)-ATPase (NKA). The FSTL1 protein is highly expressed in small-diameter neurons of the dorsal root ganglion (DRG). It is transported to axon terminals via small translucent vesicles and secreted in both spontaneous and depolarization-induced manners. Biochemical assays showed that FSTL1 binds to the α1 subunit of NKA and elevates NKA activity. Extracellular FSTL1 induced membrane hyperpolarization in cultured cells and inhibited afferent synaptic transmission in spinal cord slices by activating NKA. Genetic deletion of FSTL1 in small DRG neurons of mice resulted in enhanced afferent synaptic transmission and sensory hypersensitivity, which could be reduced by intrathecally applied FSTL1 protein. Thus, FSTL1-dependent activation of NKA regulates the threshold of somatic sensation.
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Affiliation(s)
- Kai-Cheng Li
- Institute of Neuroscience and State Key Laboratory of Neuroscience, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai, China
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Bulk properties of the lipid bilayer are not essential for the thermal stability of Na,K-ATPase from shark rectal gland or pig kidney. Biochem Biophys Res Commun 2011; 406:580-3. [PMID: 21352812 DOI: 10.1016/j.bbrc.2011.02.094] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2011] [Accepted: 02/18/2011] [Indexed: 11/21/2022]
Abstract
The thermal stability of Na,K-ATPase from pig kidney is markedly greater than that of Na,K-ATPase from shark salt glands. The role of the lipid bilayer is studied by solubilisation of the membrane-bound enzyme in the nonionic detergent octaethyleneglycoldodecylmonoether (C(12)E(8)), addition of excess dioleylphosphatidylcholine (DOPC) or palmitoyloleylphosphatidylcholine (POPC) and reconstitution of membranes by removal of detergent. At 54°C the reconstituted enzymatically active pig enzyme retains a high thermal stability, and reconstituted shark enzyme retains a low thermal stability, even with a 9-fold excess of DOPC. This result suggests that the origin of the difference in thermal stability is not related to bulk lipid properties of the native membranes.
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Dutra BK, Fernandes FA, Failace DM, Oliveira GT. Effect of Roundup® (glyphosate formulation) in the energy metabolism and reproductive traits of Hyalella castroi (Crustacea, Amphipoda, Dogielinotidae). ECOTOXICOLOGY (LONDON, ENGLAND) 2011; 20:255-63. [PMID: 21086158 DOI: 10.1007/s10646-010-0577-x] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 11/08/2010] [Indexed: 05/30/2023]
Abstract
Roundup(®) (glyphosate formulation) is a nonselective and posts emergent herbicide used for controlling aquatic weeds and different concentrations are used in cultures around the world. The objective of this investigation was to examine the effects of Roundup(®) (glyphosate formulation) on the biochemical composition, levels of lipoperoxidation, Na(+)/K(+)ATPase activity and reproductive traits in the Hyalella castroi. Amphipods were collected in summer 2009, in the southern Brazilian highlands. In the laboratory, the animals were kept in aquariums under controlled conditions for 7 days, and after this period they were exposed to 0.36, 0.52, 1.08 and 2.16 mg/l of glyphosate for 7 days. After the period of exposure, the animals were immediately frozen for determination of glycogen, proteins, lipids, triglycerides, cholesterol, levels of lipoperoxidation, and Na(+)/K(+)ATPase activity. During each day of the cultivation reproductive traits (number of reproductive pairs, ovigerous females and eggs in the marsupium) were observed. All concentrations of Roundup(®) induced significant decreases in all biochemical parameters and Na(+)/K(+)ATPase activity, and significant increase in lipoperoxidation levels. Showing this form a potentially toxic effect at very low concentrations, this pattern of results can lead to significant changes in trophic structure of limnic environments because these amphipods are important links in food chain in these habitats.
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Affiliation(s)
- Bibiana Kaiser Dutra
- Departamento de Ciências Morfofisiológicas, Laboratório de Fisiologia da Conservação, Pontifícia Universidade Católica do Rio Grande do Sul, PUCRS, Av. Ipiranga, 6681 Pd. 12A Sala 270, Caixa Postal 1429, Porto Alegre, RS, 90619-900, Brazil
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50
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Hughes E, Whittaker CAP, Barsukov IL, Esmann M, Middleton DA. A study of the membrane association and regulatory effect of the phospholemman cytoplasmic domain. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2010; 1808:1021-31. [PMID: 21130070 DOI: 10.1016/j.bbamem.2010.11.024] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/12/2010] [Revised: 11/18/2010] [Accepted: 11/22/2010] [Indexed: 10/18/2022]
Abstract
Phospholemman (PLM) is a single-span transmembrane protein belonging to the FXYD family of proteins. PLM (or FXYD1) regulates the Na,K-ATPase (NKA) ion pump by altering its affinity for K(+) and Na(+) and by reducing its hydrolytic activity. Structural studies of PLM in anionic detergent micelles have suggested that the cytoplasmic domain, which alone can regulate NKA, forms a partial helix which is stabilized by interactions with the charged membrane surface. This work examines the membrane affinity and regulatory function of a 35-amino acid peptide (PLM(38-72)) representing the PLM cytoplasmic domain. Isothermal titration calorimetry and solid-state NMR measurements confirm that PLM(38-72) associates strongly with highly anionic phospholipid membranes, but the association is weakened substantially when the negative surface charge is reduced to a more physiologically relevant environment. Membrane interactions are also weakened when the peptide is phosphorylated at S68, one of the substrate sites for protein kinases. PLM(38-72) also lowers the maximal velocity of ATP hydrolysis (V(max)) by NKA, and phosphorylation of the peptide at S68 gives rise to a partial recovery of V(max). These results suggest that the PLM cytoplasmic domain populates NKA-associated and membrane-associated states in dynamic equilibrium and that phosphorylation may alter the position of the equilibrium. Interestingly, peptides representing the cytoplasmic domains of two other FXYD proteins, Mat-8 (FXYD3) and CHIF (FXYD4), have little or no interaction with highly anionic phospholipid membranes and have no effect on NKA function. This suggests that the functional and physical properties of PLM are not conserved across the entire FXYD family.
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Affiliation(s)
- Eleri Hughes
- School of Biological Sciences, University of Liverpool, Liverpool L69 7ZB, UK
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