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Fransen P, Chen J, Vangheluwe P, Guns PJ. Contractile Behavior of Mouse Aorta Depends on SERCA2 Isoform Distribution: Effects of Replacing SERCA2a by SERCA2b. Front Physiol 2020; 11:282. [PMID: 32296344 PMCID: PMC7136392 DOI: 10.3389/fphys.2020.00282] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2019] [Accepted: 03/12/2020] [Indexed: 01/16/2023] Open
Abstract
The Sarco(endo)plasmic reticulum Ca2+ ATPase (SERCA) actively pumps Ca2+ into the sarco/endoplasmic reticulum, thereby regulating intracellular Ca2+ concentrations and associated physiological processes. Different SERCA isoforms have been described (SERCA1, 2, and 3) with SERCA2 playing a pivotal role in Ca2+ homeostasis in cardiovascular tissues. In the heart, SERCA2a is the dominant isoform and has been proposed as therapeutic target in patients with heart failure. In the vasculature, both SERCA2a and SERCA2b are expressed with SERCA2b being the predominant isoform. The physiological role of SERCA2a in the vasculature, however, remains incompletely understood. In the present study, we used gene-modified mice in which the alternative splicing of the SERCA2-encoding gene (Atp2a2), underlying the expression of SERCA2a, is prevented and SERCA2a is replaced by SERCA2b. The resulting SERCA2b/b mice provide a unique opportunity to investigate the specific contribution of SERCA2a versus SERCA2b to vascular physiology. Aortic segments of SERCA2b/b (SERCA2a-deficient) and SERCA2a/b (control) mice were mounted in organ baths to evaluate vascular reactivity. SERCA2b/b aortic rings displayed higher contractions induced by phenylephrine (1 μM). Surprisingly, the initial inositol-3-phosphate mediated phasic contraction showed a faster decay of force in SERCA2b/b mice, while the subsequent tonic contraction was larger in SERCA2b/b segments. Moreover, in the presence of the calcium channel blocker diltiazem (35 μM) SERCA2b/b aortic rings showed higher contractions compared to SERCA2a/b, suggesting that SERCA2a (deficiency) modulates the activity of non-selective cation channels. Additionally, in endothelial cell (EC)-denuded aortic segments, the SERCA-inhibitor cyclopiazonic acid (CPA) caused markedly larger contractions in SERCA2b/b mice, while the increases of cytosolic Ca2+ were similar in both strains. Hence, aortas of SERCA2b/b mice appear to have a stronger coupling of intracellular Ca2+ to contraction, which may be in agreement with the reported difference in intracellular localization of SERCA2a versus SERCA2b. Finally, EC-mediated relaxation by acetylcholine and ATP was assessed. Concentration-response-curves for ATP showed a higher sensitivity of aortic segments of SERCA2b/b mice, while no difference in potency between strains were observed for acetylcholine. In summary, despite the relative low expression of SERCA2a in the murine aorta, our results point toward a distinct role in vascular physiology.
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Affiliation(s)
- Paul Fransen
- Laboratory of Physiopharmacology, Faculty of Pharmaceutical Sciences and Faculty of Medicine and Health Sciences, University of Antwerp, Antwerp, Belgium
| | - Jialin Chen
- Laboratory of Cellular Transport Systems, KU Leuven, Leuven, Belgium
| | - Peter Vangheluwe
- Laboratory of Cellular Transport Systems, KU Leuven, Leuven, Belgium
| | - Pieter-Jan Guns
- Laboratory of Physiopharmacology, Faculty of Pharmaceutical Sciences and Faculty of Medicine and Health Sciences, University of Antwerp, Antwerp, Belgium
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Berra-Romani R, Faris P, Pellavio G, Orgiu M, Negri S, Forcaia G, Var-Gaz-Guadarrama V, Garcia-Carrasco M, Botta L, Sancini G, Laforenza U, Moccia F. Histamine induces intracellular Ca 2+ oscillations and nitric oxide release in endothelial cells from brain microvascular circulation. J Cell Physiol 2019; 235:1515-1530. [PMID: 31310018 DOI: 10.1002/jcp.29071] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2019] [Accepted: 06/21/2019] [Indexed: 02/06/2023]
Abstract
The neuromodulator histamine is able to vasorelax in human cerebral, meningeal and temporal arteries via endothelial histamine 1 receptors (H1 Rs) which result in the downstream production of nitric oxide (NO), the most powerful vasodilator transmitter in the brain. Although endothelial Ca 2+ signals drive histamine-induced NO release throughout the peripheral circulation, the mechanism by which histamine evokes NO production in human cerebrovascular endothelial cells is still unknown. Herein, we exploited the human cerebral microvascular endothelial cell line, hCMEC/D3, to assess the role of intracellular Ca 2+ signaling in histamine-induced NO release. To achieve this goal, hCMEC/D3 cells were loaded with the Ca 2+ - and NO-sensitive dyes, Fura-2/AM and DAF-FM/AM, respectively. Histamine elicited repetitive oscillations in intracellular Ca 2+ concentration in hCMEC/D3 cells throughout a concentration range spanning from 1 pM up to 300 μM. The oscillatory Ca 2+ response was suppressed by the inhibition of H 1 Rs with pyrilamine, whereas H 1 R was abundantly expressed at the protein level. We further found that histamine-induced intracellular Ca 2+ oscillations were initiated by endogenous Ca 2+ mobilization through inositol-1,4,5-trisphosphate- and nicotinic acid dinucleotide phosphate-sensitive channels and maintained over time by store-operated Ca 2+ entry. In addition, histamine evoked robust NO release that was prevented by interfering with the accompanying intracellular Ca 2+ oscillations, thereby confirming that the endothelial NO synthase is recruited by Ca 2+ spikes also in hCMEC/D3 cells. These data provide the first evidence that histamine evokes NO production from human cerebrovascular endothelial cells through intracellular Ca 2+ oscillations, thereby shedding novel light on the mechanisms by which this neuromodulator controls cerebral blood flow.
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Affiliation(s)
- Roberto Berra-Romani
- Department of Biomedicine, Biomedicine School, Benemerita Universidad Autonoma de Puebla, Puebla, Mexico
| | - Pawan Faris
- Laboratory of General Physiology, Department of Biology and Biotechnology "L. Spallanzani", University of Pavia, Pavia, Italy.,Research Center, Salahaddin University, Erbil, Kurdistan-Region of Iraq, Iraq
| | - Giorgia Pellavio
- Human Physiology Unit, Department of Molecular Medicine, University of Pavia, Pavia, Italy
| | - Matteo Orgiu
- Laboratory of General Physiology, Department of Biology and Biotechnology "L. Spallanzani", University of Pavia, Pavia, Italy
| | - Sharon Negri
- Laboratory of General Physiology, Department of Biology and Biotechnology "L. Spallanzani", University of Pavia, Pavia, Italy
| | - Greta Forcaia
- Department of Experimental Medicine, University of Milano-Bicocca, Monza, Italy
| | | | - Mario Garcia-Carrasco
- Department of Biomedicine, Biomedicine School, Benemerita Universidad Autonoma de Puebla, Puebla, Mexico
| | - Laura Botta
- Laboratory of General Physiology, Department of Biology and Biotechnology "L. Spallanzani", University of Pavia, Pavia, Italy
| | - Giulio Sancini
- Department of Experimental Medicine, University of Milano-Bicocca, Monza, Italy
| | - Umberto Laforenza
- Human Physiology Unit, Department of Molecular Medicine, University of Pavia, Pavia, Italy
| | - Francesco Moccia
- Laboratory of General Physiology, Department of Biology and Biotechnology "L. Spallanzani", University of Pavia, Pavia, Italy
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3
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Dabur R. Identification of molecular pathways affected by treatment with heartwood water extract of Pterocarpus marsupium in MCF 7 cancer cell line. J Herb Med 2017. [DOI: 10.1016/j.hermed.2017.04.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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4
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Blatter LA. Tissue Specificity: SOCE: Implications for Ca 2+ Handling in Endothelial Cells. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2017; 993:343-361. [PMID: 28900923 DOI: 10.1007/978-3-319-57732-6_18] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Many cellular functions of the vascular endothelium are regulated by fine-tuned global and local, microdomain-confined changes of cytosolic free Ca2+ ([Ca2+]i). Vasoactive agonist-induced stimulation of vascular endothelial cells (VECs) typically induces Ca2+ release through IP3 receptor Ca2+ release channels embedded in the membrane of the endoplasmic reticulum (ER) Ca2+ store, followed by Ca2+ entry from the extracellular space elicited by Ca2+ store depletion and referred to as capacitative or store-operated Ca2+ entry (SOCE). In vascular endothelial cells, SOCE is graded with the degree of store depletion and controlled locally in the subcellular microdomain where depletion occurs. SOCE provides distinct Ca2+ signals that selectively control specific endothelial functions: in calf pulmonary artery endothelial cells, the SOCE Ca2+ signal drives nitric oxide (an endothelium-derived relaxing factor of the vascular smooth muscle) production and controls activation and nuclear translocation of the transcription factor NFAT. Both cellular events are not affected by Ca2+ signals of comparable magnitude arising directly from Ca2+ release from intracellular stores, clearly indicating that SOCE regulates specific Ca2+-dependent cellular tasks by a unique and exclusive mechanism. This review discusses the mechanisms of intracellular Ca2+ regulation in vascular endothelial cells and the role of store-operated Ca2+ entry for endothelium-dependent smooth muscle relaxation and nitric oxide signaling, endothelial oxidative stress response, and excitation-transcription coupling in the vascular endothelium.
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Affiliation(s)
- Lothar A Blatter
- Department of Physiology and Biophysics, Rush University Medical Center, 1750 W. Harrison St., Chicago, IL, 60612, USA.
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Du Y, Guo D, Wu Q, Shi J, Liu D, Bi H. Protective effects of appropriate Zn2+ levels against UVB radiation-induced damage in human lens epithelial cells in vitro. J Biol Inorg Chem 2015; 21:213-26. [DOI: 10.1007/s00775-015-1324-9] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2015] [Accepted: 12/14/2015] [Indexed: 12/16/2022]
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Suehiro JI, Kanki Y, Makihara C, Schadler K, Miura M, Manabe Y, Aburatani H, Kodama T, Minami T. Genome-wide approaches reveal functional vascular endothelial growth factor (VEGF)-inducible nuclear factor of activated T cells (NFAT) c1 binding to angiogenesis-related genes in the endothelium. J Biol Chem 2014; 289:29044-59. [PMID: 25157100 DOI: 10.1074/jbc.m114.555235] [Citation(s) in RCA: 54] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
VEGF is a key regulator of endothelial cell migration, proliferation, and inflammation, which leads to activation of several signaling cascades, including the calcineurin-nuclear factor of activated T cells (NFAT) pathway. NFAT is not only important for immune responses but also for cardiovascular development and the pathogenesis of Down syndrome. By using Down syndrome model mice and clinical patient samples, we showed recently that the VEGF-calcineurin-NFAT signaling axis regulates tumor angiogenesis and tumor metastasis. However, the connection between genome-wide views of NFAT-mediated gene regulation and downstream gene function in the endothelium has not been studied extensively. Here we performed comprehensive mapping of genome-wide NFATc1 binding in VEGF-stimulated primary cultured endothelial cells and elucidated the functional consequences of VEGF-NFATc1-mediated phenotypic changes. A comparison of the NFATc1 ChIP sequence profile and epigenetic histone marks revealed that predominant NFATc1-occupied peaks overlapped with promoter-associated histone marks. Moreover, we identified two novel NFATc1 regulated genes, CXCR7 and RND1. CXCR7 knockdown abrogated SDF-1- and VEGF-mediated cell migration and tube formation. siRNA treatment of RND1 impaired vascular barrier function, caused RhoA hyperactivation, and further stimulated VEGF-mediated vascular outgrowth from aortic rings. Taken together, these findings suggest that dynamic NFATc1 binding to target genes is critical for VEGF-mediated endothelial cell activation. CXCR7 and RND1 are NFATc1 target genes with multiple functions, including regulation of cell migration, tube formation, and barrier formation in endothelial cells.
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Affiliation(s)
| | - Yasuharu Kanki
- From the Division of Vascular Biology, Systems Biology, The Research Center for Advanced Science and Technology, The University of Tokyo, Tokyo, 153-8904 Japan and
| | | | - Keri Schadler
- From the Division of Vascular Biology, the Department of Cancer Biology, Abramson Family Cancer Research Institute, University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania 19104
| | - Mai Miura
- From the Division of Vascular Biology
| | | | | | - Tatsuhiko Kodama
- Systems Biology, The Research Center for Advanced Science and Technology, The University of Tokyo, Tokyo, 153-8904 Japan and
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Bart G, Hämäläinen L, Rauhala L, Salonen P, Kokkonen M, Dunlop T, Pehkonen P, Kumlin T, Tammi M, Pasonen-Seppänen S, Tammi R. rClca2is associated with epidermal differentiation and is strongly downregulated by ultraviolet radiation. Br J Dermatol 2014; 171:376-87. [DOI: 10.1111/bjd.13038] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/02/2014] [Indexed: 12/18/2022]
Affiliation(s)
- G. Bart
- Institute of Biomedicine; University of Eastern Finland; P.O. Box 1627 FI-70211 Kuopio Finland
| | - L. Hämäläinen
- Institute of Biomedicine; University of Eastern Finland; P.O. Box 1627 FI-70211 Kuopio Finland
| | - L. Rauhala
- Institute of Biomedicine; University of Eastern Finland; P.O. Box 1627 FI-70211 Kuopio Finland
| | - P. Salonen
- Institute of Biomedicine; University of Eastern Finland; P.O. Box 1627 FI-70211 Kuopio Finland
| | - M. Kokkonen
- Institute of Biomedicine; University of Eastern Finland; P.O. Box 1627 FI-70211 Kuopio Finland
| | - T.W. Dunlop
- Institute of Biomedicine; University of Eastern Finland; P.O. Box 1627 FI-70211 Kuopio Finland
| | - P. Pehkonen
- Institute of Biomedicine; University of Eastern Finland; P.O. Box 1627 FI-70211 Kuopio Finland
| | - T. Kumlin
- Department of Environmental Science; University of Eastern Finland; P.O. Box 1627 FI-70211 Kuopio Finland
| | - M.I. Tammi
- Institute of Biomedicine; University of Eastern Finland; P.O. Box 1627 FI-70211 Kuopio Finland
| | - S. Pasonen-Seppänen
- Institute of Biomedicine; University of Eastern Finland; P.O. Box 1627 FI-70211 Kuopio Finland
| | - R.H. Tammi
- Institute of Biomedicine; University of Eastern Finland; P.O. Box 1627 FI-70211 Kuopio Finland
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Minami T. Calcineurin-NFAT activation and DSCR-1 auto-inhibitory loop: how is homoeostasis regulated? J Biochem 2014; 155:217-26. [PMID: 24505143 DOI: 10.1093/jb/mvu006] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Calcineurin-nuclear factor of activated T cells (NFAT) signalling plays a critical role not only in the immune and nervous systems, but also in cardiovascular development and pathological endothelial cell activation during angiogenesis or inflammation. Studies in NFAT-null mice demonstrated that there is high redundancy between functions of the different NFAT family members. Deletion of only one NFAT causes mild phenotypes, but compound deletions of multiple NFAT family members leads to severe abnormalities in multiple organ systems. Genome-wide transcription analysis revealed that many NFAT target genes are related to cell growth and inflammation, whereas the gene most strongly induced by NFAT in endothelial cells is an auto-inhibitory molecule, Down syndrome critical region (DSCR)-1. The NFAT-DSCR-1 signalling axis may vary depending on the cell-type or signal dosage level under the microenvironment. In the endothelium, stable expression of the DSCR-1 short isoform attenuates septic inflammatory shock, tumour growth and tumour metastasis to lung. Moreover, dysfunction of DSCR-1 and the NFAT priming kinase, DYRK1A, prevents NFAT nuclear occupancy. This change in NFAT nuclear localization is responsible for many of the features of Down syndrome. Thus, fine-tuning of the NFAT-DSCR-1 negative feedback loop may enable therapeutic manipulation in vasculopathic diseases.
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Affiliation(s)
- Takashi Minami
- Div. of Vascular Biology, RCAST, The University of Tokyo, Tokyo 153-8904, Japan
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Minami T. Genome- and epigenome-wide analysis of endothelial cell activation and inflammation. Inflamm Regen 2014. [DOI: 10.2492/inflammregen.34.094] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
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10
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Understanding the pathogenesis of Kawasaki disease by network and pathway analysis. COMPUTATIONAL AND MATHEMATICAL METHODS IN MEDICINE 2013; 2013:989307. [PMID: 23533546 PMCID: PMC3606754 DOI: 10.1155/2013/989307] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/22/2012] [Accepted: 01/04/2013] [Indexed: 12/20/2022]
Abstract
Kawasaki disease (KD) is a complex disease, leading to the damage of multisystems. The pathogen that triggers this sophisticated disease is still unknown since it was first reported in 1967. To increase our knowledge on the effects of genes in KD, we extracted statistically significant genes so far associated with this mysterious illness from candidate gene studies and genome-wide association studies. These genes contributed to susceptibility to KD, coronary artery lesions, resistance to initial IVIG treatment, incomplete KD, and so on. Gene ontology category and pathways were analyzed for relationships among these statistically significant genes. These genes were represented in a variety of functional categories, including immune response, inflammatory response, and cellular calcium ion homeostasis. They were mainly enriched in the pathway of immune response. We further highlighted the compelling immune pathway of NF-AT signal and leukocyte interactions combined with another transcription factor NF- κ B in the pathogenesis of KD. STRING analysis, a network analysis focusing on protein interactions, validated close contact between these genes and implied the importance of this pathway. This data will contribute to understanding pathogenesis of KD.
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Moccia F, Berra-Romani R, Tanzi F. Update on vascular endothelial Ca 2+ signalling: A tale of ion channels, pumps and transporters. World J Biol Chem 2012; 3:127-58. [PMID: 22905291 PMCID: PMC3421132 DOI: 10.4331/wjbc.v3.i7.127] [Citation(s) in RCA: 86] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/17/2012] [Revised: 07/04/2012] [Accepted: 07/11/2012] [Indexed: 02/05/2023] Open
Abstract
A monolayer of endothelial cells (ECs) lines the lumen of blood vessels and forms a multifunctional transducing organ that mediates a plethora of cardiovascular processes. The activation of ECs from as state of quiescence is, therefore, regarded among the early events leading to the onset and progression of potentially lethal diseases, such as hypertension, myocardial infarction, brain stroke, and tumor. Intracellular Ca2+ signals have long been know to play a central role in the complex network of signaling pathways regulating the endothelial functions. Notably, recent work has outlined how any change in the pattern of expression of endothelial channels, transporters and pumps involved in the modulation of intracellular Ca2+ levels may dramatically affect whole body homeostasis. Vascular ECs may react to both mechanical and chemical stimuli by generating a variety of intracellular Ca2+ signals, ranging from brief, localized Ca2+ pulses to prolonged Ca2+ oscillations engulfing the whole cytoplasm. The well-defined spatiotemporal profile of the subcellular Ca2+ signals elicited in ECs by specific extracellular inputs depends on the interaction between Ca2+ releasing channels, which are located both on the plasma membrane and in a number of intracellular organelles, and Ca2+ removing systems. The present article aims to summarize both the past and recent literature in the field to provide a clear-cut picture of our current knowledge on the molecular nature and the role played by the components of the Ca2+ machinery in vascular ECs under both physiological and pathological conditions.
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Affiliation(s)
- Francesco Moccia
- Francesco Moccia, Franco Tanzi, Department of Biology and Biotechnologies "Lazzaro Spallanzani", Laboratory of Physiology, University of Pavia, Via Forlanini 6, 27100 Pavia, Italy
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Abstract
Agonist-sensitive intracellular Ca2+ stores may be heterogeneous and exhibit distinct functional features. We have studied the properties of intracellular Ca2+ stores using targeted aequorins for selective measurements in different subcellular compartments. Both, HEK-293T [HEK (human embryonic kidney)-293 cells expressing the large T-antigen of SV40 (simian virus 40)] and HeLa cells accumulated Ca2+ into the ER (endoplasmic reticulum) to near millimolar concentrations and the IP3-generating agonists, carbachol and ATP, mobilized this Ca2+ pool. We find in HEK-293T, but not in HeLa cells, a distinct agonist-releasable Ca2+ pool insensitive to the SERCA (sarco/endoplasmic reticulum Ca2+ ATPase) inhibitor TBH [2,5-di-(t-butyl)-benzohydroquinone]. TG (thapsigargin) and CPA (cyclopiazonic acid) completely emptied this pool, whereas lysosomal disruption or manoeuvres collapsing endomembrane pH gradients did not. Our results indicate that SERCA3d is important for filling the TBH-resistant store as: (i) SERCA3d is more abundant in HEK-293T than in HeLa cells; (ii) the SERCA 3 ATPase activity of HEK-293T cells is not fully blocked by TBH; and (iii) the expression of SERCA3d in HeLa cells generated a TBH-resistant agonist-mobilizable compartment in the ER. Therefore the distribution of SERCA isoforms may originate the heterogeneity of the ER Ca2+ stores and this may be the basis for store specialization in diverse functions. This adds to recent evidence indicating that SERCA3 isoforms may subserve important physiological and pathophysiological mechanisms.
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McElnea E, Quill B, Docherty N, Irnaten M, Siah W, Clark A, O’Brien C, Wallace D. Oxidative stress, mitochondrial dysfunction and calcium overload in human lamina cribrosa cells from glaucoma donors. Mol Vis 2011; 17:1182-91. [PMID: 21617752 PMCID: PMC3102025] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2011] [Accepted: 04/28/2011] [Indexed: 10/27/2022] Open
Abstract
PURPOSE Oxidative stress is implicit in the pathological changes associated with glaucoma. The purpose of this study was to compare levels of oxidative stress in glial fibrillary acid-negative protein (GFAP) lamina cribrosa (LC) cells obtained from the optic nerve head (ONH) region of 5 normal (NLC) and 4 glaucomatous (GLC) human donor eyes and to also examine mitochondrial function and calcium homeostasis in this region of the ONH. METHODS Intracellular reactive oxygen species (ROS) production was examined by a thiobarbituric acid reactive substances (TBARS) assay which measures malondialdehyde (MDA), a naturally occurring product of lipid peroxidation and is used as an indicator of oxidative stress. Mitochondrial membrane potential (MMP) and intracellular calcium ([Ca(2+)](i)) levels were evaluated by flow cytometry using the JC-1 (5,5',6,6'-tetrachloro-1,1',3,3'-tetrabenzimidazolecarbocyanine iodide) and fluo-4/AM probes respectively. Anti-oxidant and Ca(2+) transport system gene and protein expression were determined by real time polymerase chain reaction (RT-PCR) using gene-specific primer/probe sets and western immunoblotting, respectively. RESULTS Intracellular ROS production was increased in GLC compared to NLC (27.19 ± 7.05 µM MDA versus 14.59 ± 0.82 µM MDA, p < 0.05). Expression of the anti-oxidants Aldo-keto reductase family 1 member C1 (AKR1C1) and Glutamate cysteine ligase catalytic subunit (GCLC) were significantly lower in GLC (p = 0.02) compared to NLC control. MMP was lower in GLC (57.5 ± 6.8%) compared to NLC (41.8 ± 5.3%). [Ca(2+)](i) levels were found to be higher (p < 0.001) in GLC cells compared to NLC. Expression of the plasma membrane Ca(2+)/ATPase (PMCA) and the sodium-calcium (NCX) exchangers were lower, while intracellular sarco-endoplasmic reticulum Ca(2+)/ATPase 3 (SERCA) expression was significantly higher in GLC compared to NLC. Subjection of NLC cells to oxidative stress (200 µM H(2)0(2)) reduced expression of Na(+)/Ca2(+) exchanger 1 (NCX 1), plasma membrane Ca2+ ATPase 1 (PMCA 1), and PMCA 4 as determined by RT-PCR. CONCLUSIONS Our data finds evidence of oxidative stress, mitochondrial dysfunction and impaired calcium extrusion in GLC cells compared to NLC cells and suggests their importance in the pathological changes occurring at the ONH in glaucoma. Future therapies may target reducing oxidative stress and / or [Ca(2+)](i).
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Affiliation(s)
- E.M. McElnea
- Institute of Ophthalmology, Mater Misericordiae University Hospital, Dublin, Ireland,University College Dublin School of Medicine-Medical Science, University College Dublin, Dublin, Ireland
| | - B. Quill
- Institute of Ophthalmology, Mater Misericordiae University Hospital, Dublin, Ireland,University College Dublin School of Medicine-Medical Science, University College Dublin, Dublin, Ireland
| | - N.G. Docherty
- Institute of Ophthalmology, Mater Misericordiae University Hospital, Dublin, Ireland,University College Dublin School of Medicine-Medical Science, University College Dublin, Dublin, Ireland
| | - M. Irnaten
- Institute of Ophthalmology, Mater Misericordiae University Hospital, Dublin, Ireland,University College Dublin School of Medicine-Medical Science, University College Dublin, Dublin, Ireland
| | - W.F. Siah
- Institute of Ophthalmology, Mater Misericordiae University Hospital, Dublin, Ireland,University College Dublin School of Medicine-Medical Science, University College Dublin, Dublin, Ireland
| | - A.F. Clark
- Department of Cell Biology & Anatomy and the North Texas Eye Research Institute, University North Texas Health Science Center, Ft. Worth, TX
| | - C.J. O’Brien
- Institute of Ophthalmology, Mater Misericordiae University Hospital, Dublin, Ireland,University College Dublin School of Medicine-Medical Science, University College Dublin, Dublin, Ireland
| | - D.M. Wallace
- Institute of Ophthalmology, Mater Misericordiae University Hospital, Dublin, Ireland,University College Dublin School of Medicine-Medical Science, University College Dublin, Dublin, Ireland
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Bhattacharyya S, Deb J, Patra AK, Thuy Pham DA, Chen W, Vaeth M, Berberich-Siebelt F, Klein-Hessling S, Lamperti ED, Reifenberg K, Jellusova J, Schweizer A, Nitschke L, Leich E, Rosenwald A, Brunner C, Engelmann S, Bommhardt U, Avots A, Müller MR, Kondo E, Serfling E. NFATc1 affects mouse splenic B cell function by controlling the calcineurin--NFAT signaling network. ACTA ACUST UNITED AC 2011; 208:823-39. [PMID: 21464221 PMCID: PMC3135343 DOI: 10.1084/jem.20100945] [Citation(s) in RCA: 96] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Mouse B cells lacking NFATc1 exhibit defective proliferation, survival, isotype class switching, cytokine production, and T cell help. By studying mice in which the Nfatc1 gene was inactivated in bone marrow, spleen, or germinal center B cells, we show that NFATc1 supports the proliferation and suppresses the activation-induced cell death of splenic B cells upon B cell receptor (BCR) stimulation. BCR triggering leads to expression of NFATc1/αA, a short isoform of NFATc1, in splenic B cells. NFATc1 ablation impaired Ig class switch to IgG3 induced by T cell–independent type II antigens, as well as IgG3+ plasmablast formation. Mice bearing NFATc1−/− B cells harbor twofold more interleukin 10–producing B cells. NFATc1−/− B cells suppress the synthesis of interferon-γ by T cells in vitro, and these mice exhibit a mild clinical course of experimental autoimmune encephalomyelitis. In large part, the defective functions of NFATc1−/− B cells are caused by decreased BCR-induced Ca2+ flux and calcineurin (Cn) activation. By affecting CD22, Rcan1, CnA, and NFATc1/αA expression, NFATc1 controls the Ca2+-dependent Cn–NFAT signaling network and, thereby, the fate of splenic B cells upon BCR stimulation.
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Affiliation(s)
- Sankar Bhattacharyya
- Department of Molecular Pathology, University of Würzburg, D-97080 Würzburg, Germany
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15
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Rosado JA, Pariente JA, Salido GM, Redondo PC. SERCA2b activity is regulated by cyclophilins in human platelets. Arterioscler Thromb Vasc Biol 2010; 30:419-25. [PMID: 20139366 DOI: 10.1161/atvbaha.109.194530] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
OBJECTIVE The role of cyclophilins (chaperones that are widely expressed in different cell types, including human platelets) was explored in sarcoendoplasmic calcium (Ca(2+)) adenosine triphosphatase (SERCA) activity. METHODS AND RESULTS Cyclophilin inhibition by cyclosporin A (CsA) evoked a time- and concentration-dependent reduction of Ca(2+) uptake by SERCA2b. However, other Ca(2+)-adenosine triphosphatases expressed in platelets, such as SERCA3 and plasma membrane Ca(2+) adenosine triphophatase, remained unaltered after CsA treatment. Cypermethrin, a non-CsA-related calcineurin inhibitor, did not alter SERCA2b activity. Furthermore, SERCA2b was affected by other CsA analogues, which do not interfere with calcineurin, such as PKF-211-811-NX5 (NIM811) and sanglifehrin A. Inhibition of the immunophilin family members using FK506 (tacrolimus) did not alter SERCA2b ability to sequester Ca(2+) into the dense tubular system. Coimmunoprecipitation experiments confirmed that cyclophilin A associates with SERCA2b and stromal interaction molecule-1 in resting platelets. This interaction is attenuated by the physiological agonist thrombin but enhanced by treatment with CsA or sanglifehrin A. CONCLUSIONS Cyclophilin A is a regulator of SERCA2b in human platelets.
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Affiliation(s)
- Juan A Rosado
- Department of Physiology, University of Extremadura, Avd. Universidad s/n, Cáceres 10071, Spain
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16
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Searls YM, Loganathan R, Smirnova IV, Stehno-Bittel L. Intracellular Ca2+ regulating proteins in vascular smooth muscle cells are altered with type 1 diabetes due to the direct effects of hyperglycemia. Cardiovasc Diabetol 2010; 9:8. [PMID: 20122173 PMCID: PMC2829469 DOI: 10.1186/1475-2840-9-8] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/26/2009] [Accepted: 02/01/2010] [Indexed: 02/01/2023] Open
Abstract
Background Diminished calcium (Ca2+) transients in response to physiological agonists have been reported in vascular smooth muscle cells (VSMCs) from diabetic animals. However, the mechanism responsible was unclear. Methodology/Principal Findings VSMCs from autoimmune type 1 Diabetes Resistant Bio-Breeding (DR-BB) rats and streptozotocin-induced rats were examined for levels and distribution of inositol trisphosphate receptors (IP3R) and the SR Ca2+ pumps (SERCA 2 and 3). Generally, a decrease in IP3R levels and dramatic increase in ryanodine receptor (RyR) levels were noted in the aortic samples from diabetic animals. Redistribution of the specific IP3R subtypes was dependent on the rat model. SERCA 2 was redistributed to a peri-nuclear pattern that was more prominent in the DR-BB diabetic rat aorta than the STZ diabetic rat. The free intracellular Ca2+ in freshly dispersed VSMCs from control and diabetic animals was monitored using ratiometric Ca2+ sensitive fluorophores viewed by confocal microscopy. In control VSMCs, basal fluorescence levels were significantly higher in the nucleus relative to the cytoplasm, while in diabetic VSMCs they were essentially the same. Vasopressin induced a predictable increase in free intracellular Ca2+ in the VSMCs from control rats with a prolonged and significantly blunted response in the diabetic VSMCs. A slow rise in free intracellular Ca2+ in response to thapsigargin, a specific blocker of SERCA was seen in the control VSMCs but was significantly delayed and prolonged in cells from diabetic rats. To determine whether the changes were due to the direct effects of hyperglycemica, experiments were repeated using cultured rat aortic smooth muscle cells (A7r5) grown in hyperglycemic and control conditions. In general, they demonstrated the same changes in protein levels and distribution as well as the blunted Ca2+ responses to vasopressin and thapsigargin as noted in the cells from diabetic animals. Conclusions/Significance This work demonstrates that the previously-reported reduced Ca2+ signaling in VSMCs from diabetic animals is related to decreases and/or redistribution in the IP3R Ca2+ channels and SERCA proteins. These changes can be duplicated in culture with high glucose levels.
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Affiliation(s)
- Yvonne M Searls
- Department of Physical Therapy and Rehabilitation Science, University of Kansas Medical Center, Kansas City, KS 66160, USA
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17
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Vangheluwe P, Sepúlveda MR, Missiaen L, Raeymaekers L, Wuytack F, Vanoevelen J. Intracellular Ca2+- and Mn2+-Transport ATPases. Chem Rev 2009; 109:4733-59. [DOI: 10.1021/cr900013m] [Citation(s) in RCA: 71] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Affiliation(s)
- Peter Vangheluwe
- Laboratory of Ca2+-transport ATPases and Laboratory of Molecular and Cellular Signaling, Department of Molecular Cell Biology, Katholieke Universiteit Leuven, Leuven, Belgium
| | - M. Rosario Sepúlveda
- Laboratory of Ca2+-transport ATPases and Laboratory of Molecular and Cellular Signaling, Department of Molecular Cell Biology, Katholieke Universiteit Leuven, Leuven, Belgium
| | - Ludwig Missiaen
- Laboratory of Ca2+-transport ATPases and Laboratory of Molecular and Cellular Signaling, Department of Molecular Cell Biology, Katholieke Universiteit Leuven, Leuven, Belgium
| | - Luc Raeymaekers
- Laboratory of Ca2+-transport ATPases and Laboratory of Molecular and Cellular Signaling, Department of Molecular Cell Biology, Katholieke Universiteit Leuven, Leuven, Belgium
| | - Frank Wuytack
- Laboratory of Ca2+-transport ATPases and Laboratory of Molecular and Cellular Signaling, Department of Molecular Cell Biology, Katholieke Universiteit Leuven, Leuven, Belgium
| | - Jo Vanoevelen
- Laboratory of Ca2+-transport ATPases and Laboratory of Molecular and Cellular Signaling, Department of Molecular Cell Biology, Katholieke Universiteit Leuven, Leuven, Belgium
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18
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Dellis O, Arbabian A, Brouland JP, Kovàcs T, Rowe M, Chomienne C, Joab I, Papp B. Modulation of B-cell endoplasmic reticulum calcium homeostasis by Epstein-Barr virus latent membrane protein-1. Mol Cancer 2009; 8:59. [PMID: 19650915 PMCID: PMC3098015 DOI: 10.1186/1476-4598-8-59] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2009] [Accepted: 08/03/2009] [Indexed: 12/14/2022] Open
Abstract
Background Calcium signaling plays an important role in B lymphocyte survival and activation, and is critically dependent on the inositol-1,4,5-tris-phosphate-induced release of calcium stored in the endoplasmic reticulum (ER). Calcium is accumulated in the ER by Sarco/Endoplasmic Reticulum Calcium ATPases (SERCA enzymes), and therefore these enzymes play an important role in ER calcium homeostasis and in the control of B of cell activation. Because Epstein-Barr virus (EBV) can immortalize B cells and contributes to lymphomagenesis, in this work the effects of the virus on SERCA-type calcium pump expression and calcium accumulation in the endoplasmic reticulum of B cells was investigated. Results Two Sarco-Endoplasmic Reticulum Calcium transport ATPase isoforms, the low Ca2+-affinity SERCA3, and the high Ca2+-affinity SERCA2 enzymes are simultaneously expressed in B cells. Latency type III infection of Burkitt's lymphoma cell lines with immortalization-competent virus expressing the full set of latency genes selectively decreased the expression of SERCA3 protein, whereas infection with immortalization-deficient virus that does not express the EBNA2 or LMP-1 viral genes was without effect. Down-modulation of SERCA3 expression could be observed upon LMP-1, but not EBNA2 expression in cells carrying inducible transgenes, and LMP-1 expression was associated with enhanced resting cytosolic calcium levels and increased calcium storage in the endoplasmic reticulum. Similarly to virus-induced B cell immortalisation, SERCA3 expression was also decreased in normal B cells undergoing activation and blastic transformation in germinal centers of lymph node follicles. Conclusion The data presented in this work indicate that EBV-induced immortalization leads to the remodelling of ER calcium homeostasis of B cells by LMP-1 that copies a previously unknown normal phenomenon taking place during antigen driven B cell activation. The functional remodelling of ER calcium homeostasis by down-regulation of SERCA3 expression constitutes a previously unknown mechanism involved in EBV-induced B cell immortalisation.
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Affiliation(s)
- Olivier Dellis
- Institut National de la Santé et de la Recherche Médicale, Inserm UMR-S 940, Institut Universitaire d'Hématologie, Université Paris VII, Service d'Anatomie et Cytologie Pathologiques, Hôpital Lariboisière, 16, rue de la Grange aux Belles, 75010 Paris, France.
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Rinne A, Banach K, Blatter LA. Regulation of nuclear factor of activated T cells (NFAT) in vascular endothelial cells. J Mol Cell Cardiol 2009; 47:400-10. [PMID: 19540841 DOI: 10.1016/j.yjmcc.2009.06.010] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/24/2009] [Revised: 06/08/2009] [Accepted: 06/12/2009] [Indexed: 11/19/2022]
Abstract
Proteins of the NFAT family (nuclear factor of activated T cells) are Ca(2+)-sensitive transcription factors, which are involved in hypertrophic cardiovascular remodeling. Activation and nuclear translocation is mediated by dephosphorylation by the Ca(2+)-sensitive phosphatase calcineurin (CaN). We identified Ca(2+) signals that induced nuclear translocation of NFAT in cultured calf pulmonary artery endothelial (CPAE) cells using confocal fluorescence microscopy to measure simultaneously [Ca(2+)](i) and subcellular localization of NFAT-GFP (isoforms NFATc1 and NFATc3). The vasoactive agonists ATP (5 microM) or bradykinin (20 microM) in the presence of 2 mM extracellular Ca(2+) induced Ca(2+) release from the endoplasmic reticulum (ER) and activated capacitative Ca(2+) entry (CCE), which caused robust translocation of NFAT to the nucleus. This effect was sensitive to the CaN-inhibitor cyclosporin A (1 microM). Influx of extracellular Ca(2+) via CCE, but not ER Ca(2+) release was identified as the activating Ca(2+) source. NFAT was also activated by Ca(2+) influx induced by cell swelling, reverse mode Na/Ca exchange or ionomycin treatment. NFAT regulation was isoform-specific. Whereas activation of NFATc1-GFP by ATP resulted in persistent nuclear localization, NFATc3-GFP was only transiently imported into the nucleus, followed by rapid export back to the cytoplasm. Inhibition of nuclear kinases, which mediate export of NFAT via phosphorylation, or direct block of nuclear export (Leptomycin B) resulted in stable nuclear localization of NFATc3. These data demonstrate that extracellular Ca(2+) entry mediates NFAT activation. Furthermore, the regulation of nuclear localization of NFAT is isoform-specific and dependent on nuclear export processes.
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Affiliation(s)
- Andreas Rinne
- Department of Molecular Biophysics and Physiology, Rush University Medical Center, Chicago, IL 60612, USA
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Chandrasekera PC, Kargacin ME, Deans JP, Lytton J. Determination of apparent calcium affinity for endogenously expressed human sarco(endo)plasmic reticulum calcium-ATPase isoform SERCA3. Am J Physiol Cell Physiol 2009; 296:C1105-14. [DOI: 10.1152/ajpcell.00650.2008] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
The sarco(endo)plasmic reticulum Ca2+-ATPases (SERCAs) play a crucial role in regulating free cytosolic Ca2+ concentration in diverse cell types. It has been shown that recombinant SERCA3, when measured in heterologous systems, exhibits low apparent affinity for Ca2+; however, Ca2+ affinity of native SERCA3 in an endogenous setting has not been examined. Such a measurement is complicated, because SERCA3 is always coexpressed with the housekeeping isoform SERCA2b. We used a fluorescence-based assay for monitoring continuous Ca2+ uptake into microsomes to examine the properties of endogenous human SERCA3 and SERCA2b. The kinetic parameters were derived using a cooperative two-component uptake model for Ca2+ activation, and the values assigned to SERCA3 were confirmed using the highly specific human SERCA3 inhibitory antibody PL/IM430. First, using recombinant human SERCA3 and SERCA2b proteins transiently expressed in HEK-293 cells, we confirmed the previously observed low apparent Ca2+ affinity for SERCA3 compared with SERCA2b (1.10 ± 0.04 vs. 0.26 ± 0.01 μM), and using mixtures of recombinant protein isoforms, we validated the two-component uptake model. Then we determined apparent Ca2+ affinity for SERCA proteins present endogenously in cultured Jurkat T lymphocytes and freshly isolated human tonsil lymphocytes. The apparent Ca2+ affinity in these two preparations was 1.04 ± 0.07 and 1.1 ± 0.2 μM for SERCA3 and 0.27 ± 0.02 and 0.26 ± 0.01 μM for SERCA2b, respectively. Our data demonstrate, for the first time, that affinity for Ca2+ is inherently lower for SERCA3 expressed in situ than for other SERCA isoforms.
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