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Murakami M, Sun N, Li F, Feuchtinger A, Gomez-Sanchez C, Fassnacht M, Reincke M, Bancos I, Walch A, Kroiss M, Beuschlein F. In Situ Metabolomics of Cortisol-Producing Adenomas. Clin Chem 2023; 69:149-159. [PMID: 36544353 PMCID: PMC9898844 DOI: 10.1093/clinchem/hvac191] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2022] [Accepted: 10/11/2022] [Indexed: 12/24/2022]
Abstract
BACKGROUND Recent advances in omics techniques have allowed detailed genetic characterization of cortisol-producing adrenal adenoma (CPA). In contrast, the pathophysiology of CPAs has not been elucidated in detail on the level of tumor metabolic alterations. METHODS The current study conducted a comprehensive mass spectrometry imaging (MSI) map of CPAs in relation to clinical phenotypes and immunohistochemical profiles of steroidogenic enzymes. The study cohort comprised 46 patients with adrenal tumors including CPAs (n 35) and nonfunctional adenomas (n 11). RESULTS Severity of cortisol hypersecretion was significantly correlated with 29 metabolites (adjusted P 0.05). Adrenal androgens derived from the classic androgen pathway were inversely correlated with both cortisol secretion (rs 0.41, adjusted P 0.035) and CYP11B1 expression (rs 0.77, adjusted P 2.00E-08). The extent of cortisol excess and tumor CYP11B1 expression further correlated with serotonin (rs 0.48 and 0.62, adjusted P 0.008 and 2.41E-05). Tumor size was found to be correlated with abundance of 13 fatty acids (adjusted P 0.05) and negatively associated with 9 polyunsaturated fatty acids including phosphatidic acid 38:8 (rs 0.56, adjusted P 0.009). CONCLUSIONS MSI reveals novel metabolic links between endocrine function and tumorigenesis, which will further support the understanding of CPA pathophysiology.
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Affiliation(s)
- Masanori Murakami
- Medizinische Klinik und Poliklinik IV, Klinikum der Universität, Ludwig-Maximilians-Universität München, Munich, Germany,Department of Molecular Endocrinology and Metabolism, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, Tokyo, Japan
| | - Na Sun
- Research Unit Analytical Pathology, Helmholtz Zentrum München, German Research Center for Environmental Health (GmbH), Neuherberg, Germany
| | - Fengxia Li
- Research Unit Analytical Pathology, Helmholtz Zentrum München, German Research Center for Environmental Health (GmbH), Neuherberg, Germany,Department of Neuro- and Sensory Physiology, University Medical Center Göttingen, Göttingen, Germany
| | - Annette Feuchtinger
- Research Unit Analytical Pathology, Helmholtz Zentrum München, German Research Center for Environmental Health (GmbH), Neuherberg, Germany
| | - Celso Gomez-Sanchez
- Division of Endocrinology, G.V. (Sonny) Montgomery VA Medical Center and the University of Mississippi Medical Center, Jackson, Mississippi, USA
| | - Martin Fassnacht
- Department of Internal Medicine I, Division of Endocrinology and Diabetology, University Hospital Würzburg, University of Würzburg, Würzburg, Germany
| | - Martin Reincke
- Medizinische Klinik und Poliklinik IV, Klinikum der Universität, Ludwig-Maximilians-Universität München, Munich, Germany
| | - Irina Bancos
- Division of Endocrinology, Mayo Clinic, Rochester, Minnesota, USA
| | - Axel Walch
- Research Unit Analytical Pathology, Helmholtz Zentrum München, German Research Center for Environmental Health (GmbH), Neuherberg, Germany
| | - Matthias Kroiss
- Medizinische Klinik und Poliklinik IV, Klinikum der Universität, Ludwig-Maximilians-Universität München, Munich, Germany,Department of Internal Medicine I, Division of Endocrinology and Diabetology, University Hospital Würzburg, University of Würzburg, Würzburg, Germany,Comprehensive Cancer Center Mainfranken, University of Würzburg, Würzburg, Germany
| | - Felix Beuschlein
- Medizinische Klinik und Poliklinik IV, Klinikum der Universität, Ludwig-Maximilians-Universität München, Munich, Germany,Department of Endocrinology, Diabetology and Clinical Nutrition, University Hospital Zurich (USZ) and University of Zurich (UZH), Zurich, Switzerland
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2
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Villanueva J, Gimenez-Molina Y, Davletov B, Gutiérrez LM. Vesicle Fusion as a Target Process for the Action of Sphingosine and Its Derived Drugs. Int J Mol Sci 2022; 23:ijms23031086. [PMID: 35163009 PMCID: PMC8834808 DOI: 10.3390/ijms23031086] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2021] [Revised: 01/13/2022] [Accepted: 01/18/2022] [Indexed: 11/16/2022] Open
Abstract
The fusion of membranes is a central part of the physiological processes involving the intracellular transport and maturation of vesicles and the final release of their contents, such as neurotransmitters and hormones, by exocytosis. Traditionally, in this process, proteins, such SNAREs have been considered the essential components of the fusion molecular machinery, while lipids have been seen as merely structural elements. Nevertheless, sphingosine, an intracellular signalling lipid, greatly increases the release of neurotransmitters in neuronal and neuroendocrine cells, affecting the exocytotic fusion mode through the direct interaction with SNAREs. Moreover, recent studies suggest that FTY-720 (Fingolimod), a sphingosine structural analogue used in the treatment of multiple sclerosis, simulates sphingosine in the promotion of exocytosis. Furthermore, this drug also induces the intracellular fusion of organelles such as dense vesicles and mitochondria causing cell death in neuroendocrine cells. Therefore, the effect of sphingosine and synthetic derivatives on the heterologous and homologous fusion of organelles can be considered as a new mechanism of action of sphingolipids influencing important physiological processes, which could underlie therapeutic uses of sphingosine derived lipids in the treatment of neurodegenerative disorders and cancers of neuronal origin such neuroblastoma.
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Affiliation(s)
- José Villanueva
- Instituto de Neurociencias, CSIC-Universidad Miguel Hernández, Cra de Valencia S/N, Sant Joan d’Alacant, 03550 Alicante, Spain;
- Correspondence: (J.V.); (L.M.G.)
| | - Yolanda Gimenez-Molina
- Instituto de Neurociencias, CSIC-Universidad Miguel Hernández, Cra de Valencia S/N, Sant Joan d’Alacant, 03550 Alicante, Spain;
| | - Bazbek Davletov
- Department of Biomedical Science, University of Sheffield, Sheffield S10 2TN, UK;
| | - Luis M. Gutiérrez
- Instituto de Neurociencias, CSIC-Universidad Miguel Hernández, Cra de Valencia S/N, Sant Joan d’Alacant, 03550 Alicante, Spain;
- Correspondence: (J.V.); (L.M.G.)
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3
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Tsutsumi T, Ino M, Shimizu Y, Kawabata K, Nishi H, Tokumura A. Altered plasma levels of lysophospholipids in response to adrenalectomy of rats. Prostaglandins Other Lipid Mediat 2021; 156:106579. [PMID: 34245896 DOI: 10.1016/j.prostaglandins.2021.106579] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2020] [Revised: 07/02/2021] [Accepted: 07/06/2021] [Indexed: 11/15/2022]
Abstract
The aim of this study was to investigate effects of reduced stress hormone by adrenalectomy on rat plasma levels of lysophosphatidic acid (LPA) and other lysophospholipids. We measured activities of lysophospholipase D (lysoPLD) in plasma and lipid phosphate phosphatase (LPP) in blood by determining choline and inorganic phosphate, respectively. LPA, lysophosphatidylcholine (LPC), lysophosphatidylethanolamine (LPE), lysophosphatidylinositol (LPI), lysophosphatidylserine (LPS) and lysophosphatodylglycerol were quantified by LC-MS/MS. In adrenalectomized rats, plasma levels of LPA, LPE, LPS and LPI, but not LPC, were increased. The increased level of LPA were due to decreased LPC level, increases plasma activity of lysoPLD toward LPC and decreased LPP activity toward LPA. Daily injections of deoxycoricosterone into rats selectively reversed increased level of LPS. Our results suggest enzymatic mechanism for increased plasma level of LPA, and indicate that the circulating levels of lysophospholipids including LPA in rats are differently affected by artificial suppression of release of adrenergic hormones.
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Affiliation(s)
- Toshihiko Tsutsumi
- Graduate School of Clinical Pharmacy, Kyushu University of Health and Welfare, 1714-1 Yoshinomachi, Nobeoka, 882-8508, Japan
| | - Masaki Ino
- Graduate School of Biomedical Sciences, Tokushima University, 1-78-1 Shomachi, Tokushima, 770-8505, Japan
| | - Yoshibumi Shimizu
- Graduate School of Biomedical Sciences, Tokushima University, 1-78-1 Shomachi, Tokushima, 770-8505, Japan
| | - Kohei Kawabata
- Department of Pharmacy, Yasuda Women's University, 13-6-1 Yasuhigashi, Asaminamiku, Hiroshima, 731-0153, Japan
| | - Hiroyuki Nishi
- Department of Pharmacy, Yasuda Women's University, 13-6-1 Yasuhigashi, Asaminamiku, Hiroshima, 731-0153, Japan
| | - Akira Tokumura
- Graduate School of Biomedical Sciences, Tokushima University, 1-78-1 Shomachi, Tokushima, 770-8505, Japan; Department of Pharmacy, Yasuda Women's University, 13-6-1 Yasuhigashi, Asaminamiku, Hiroshima, 731-0153, Japan.
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4
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Permissive Modulation of Sphingosine-1-Phosphate-Enhanced Intracellular Calcium on BK Ca Channel of Chromaffin Cells. Int J Mol Sci 2021; 22:ijms22042175. [PMID: 33671654 PMCID: PMC7926978 DOI: 10.3390/ijms22042175] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2021] [Revised: 02/10/2021] [Accepted: 02/18/2021] [Indexed: 12/18/2022] Open
Abstract
Sphingosine-1-phosphate (S1P), is a signaling sphingolipid which acts as a bioactive lipid mediator. We assessed whether S1P had multiplex effects in regulating the large-conductance Ca2+-activated K+ channel (BKCa) in catecholamine-secreting chromaffin cells. Using multiple patch-clamp modes, Ca2+ imaging, and computational modeling, we evaluated the effects of S1P on the Ca2+-activated K+ currents (IK(Ca)) in bovine adrenal chromaffin cells and in a pheochromocytoma cell line (PC12). In outside-out patches, the open probability of BKCa channel was reduced with a mean-closed time increment, but without a conductance change in response to a low-concentration S1P (1 µM). The intracellular Ca2+ concentration (Cai) was elevated in response to a high-dose (10 µM) but not low-dose of S1P. The single-channel activity of BKCa was also enhanced by S1P (10 µM) in the cell-attached recording of chromaffin cells. In the whole-cell voltage-clamp, a low-dose S1P (1 µM) suppressed IK(Ca), whereas a high-dose S1P (10 µM) produced a biphasic response in the amplitude of IK(Ca), i.e., an initial decrease followed by a sustained increase. The S1P-induced IK(Ca) enhancement was abolished by BAPTA. Current-clamp studies showed that S1P (1 µM) increased the action potential (AP) firing. Simulation data revealed that the decreased BKCa conductance leads to increased AP firings in a modeling chromaffin cell. Over a similar dosage range, S1P (1 µM) inhibited IK(Ca) and the permissive role of S1P on the BKCa activity was also effectively observed in the PC12 cell system. The S1P-mediated IK(Ca) stimulation may result from the elevated Cai, whereas the inhibition of BKCa activity by S1P appears to be direct. By the differentiated tailoring BKCa channel function, S1P can modulate stimulus-secretion coupling in chromaffin cells.
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5
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Garcia-Martinez V, Gimenez-Molina Y, Villanueva J, Darios FD, Davletov B, Gutiérrez LM. Emerging evidence for the modulation of exocytosis by signalling lipids. FEBS Lett 2018; 592:3493-3503. [PMID: 29962039 PMCID: PMC6282582 DOI: 10.1002/1873-3468.13178] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2018] [Revised: 06/01/2018] [Accepted: 06/27/2018] [Indexed: 01/22/2023]
Abstract
Membrane fusion is a key event in exocytosis of neurotransmitters and hormones stored in intracellular vesicles. In this process, soluble N‐ethylmaleimide sensitive factor attachment protein receptor (SNARE) proteins are essential components of the exocytotic molecular machinery, while lipids have been seen traditionally as structural elements. However, the so‐called signalling lipids, such as sphingosine and arachidonic acid, interact with SNAREs and directly modulate the frequency and mode of fusion events. Interestingly, recent work has proved that the sphingosine analogue FTY‐720, used in the treatment of multiple sclerosis, mimics the effects of signalling lipids. In the present Review, we discuss recent investigations suggesting that endogenous signalling lipids and synthetic analogues can modulate important physiological aspects of secretion, such as quantal release, vesicle recruitment into active sites, vesicle transport and even organelle fusion in the cytosol. Therefore, these compounds are far from being merely structural components of cellular membranes.
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Affiliation(s)
- Virginia Garcia-Martinez
- Instituto de Neurociencias de Alicante, Consejo Superior de Investigaciones Científicas-Universidad Miguel Hernández de Elche, Sant Joan d'Alacant, Alicante, Spain
| | - Yolanda Gimenez-Molina
- Instituto de Neurociencias de Alicante, Consejo Superior de Investigaciones Científicas-Universidad Miguel Hernández de Elche, Sant Joan d'Alacant, Alicante, Spain
| | - José Villanueva
- Instituto de Neurociencias de Alicante, Consejo Superior de Investigaciones Científicas-Universidad Miguel Hernández de Elche, Sant Joan d'Alacant, Alicante, Spain
| | - Frederic D Darios
- Inserm, U1127, CNRS, UMR 7225, Institut du Cerveau et de la Moelle épinière, ICM, Sorbonne Université, Paris, France
| | - Bazbek Davletov
- Department of Biomedical Sciences, University of Sheffield, UK
| | - Luis M Gutiérrez
- Instituto de Neurociencias de Alicante, Consejo Superior de Investigaciones Científicas-Universidad Miguel Hernández de Elche, Sant Joan d'Alacant, Alicante, Spain
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6
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Harada K, Kitaguchi T, Kamiya T, Aung KH, Nakamura K, Ohta K, Tsuboi T. Lysophosphatidylinositol-induced activation of the cation channel TRPV2 triggers glucagon-like peptide-1 secretion in enteroendocrine L cells. J Biol Chem 2017; 292:10855-10864. [PMID: 28533434 DOI: 10.1074/jbc.m117.788653] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2017] [Revised: 05/17/2017] [Indexed: 01/07/2023] Open
Abstract
The lysophosphatidylinositol (LPI) has crucial roles in multiple physiological processes, including insulin exocytosis from pancreatic islets. However, the role of LPI in secretion of glucagon-like peptide-1 (GLP-1), a hormone that enhances glucose-induced insulin secretion, is unclear. Here, we used the murine enteroendocrine L cell line GLUTag and primary murine small intestinal cells to elucidate the mechanism of LPI-induced GLP-1 secretion. Exogenous LPI addition increased intracellular Ca2+ concentrations ([Ca2+] i ) in GLUTag cells and induced GLP-1 secretion from both GLUTag and acutely prepared primary intestinal cells. The [Ca2+] i increase was suppressed by an antagonist for G protein-coupled receptor 55 (GPR55) and by silencing of GPR55 expression, indicating involvement of Gq and G12/13 signaling pathways in the LPI-induced increased [Ca2+] i levels and GLP-1 secretion. However, GPR55 agonists did not mimic many of the effects of LPI. We also found that phospholipase C inhibitor and Rho-associated kinase inhibitor suppressed the [Ca2+] i increase and that LPI increased the number of focal adhesions, indicating actin reorganization. Of note, blockage or silencing of transient receptor potential cation channel subfamily V member 2 (TRPV2) channels suppressed both the LPI-induced [Ca2+] i increase and GLP-1 secretion. Furthermore, LPI accelerated TRPV2 translocation to the plasma membrane, which was significantly suppressed by a GPR55 antagonist. These findings suggest that TRPV2 activation via actin reorganization induced by Gq and G12/13 signaling is involved in LPI-stimulated GLP-1 secretion in enteroendocrine L cells. Because GPR55 agonists largely failed to mimic the effects of LPI, its actions on L cells are at least partially independent of GPR55 activation.
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Affiliation(s)
- Kazuki Harada
- From the Department of Life Sciences, Graduate School of Arts and Sciences, The University of Tokyo, Tokyo 153-8902, Japan
| | - Tetsuya Kitaguchi
- Cell Signaling Group, Waseda Bioscience Research Institute in Singapore (WABIOS), Singapore 138667, Singapore.,Comprehensive Research Organization, Waseda University, Tokyo 162-0041, Japan, and
| | - Taichi Kamiya
- From the Department of Life Sciences, Graduate School of Arts and Sciences, The University of Tokyo, Tokyo 153-8902, Japan
| | - Kyaw Htet Aung
- National Research Institute for Child Health and Development, Tokyo 157-8535, Japan
| | - Kazuaki Nakamura
- National Research Institute for Child Health and Development, Tokyo 157-8535, Japan
| | - Kunihiro Ohta
- From the Department of Life Sciences, Graduate School of Arts and Sciences, The University of Tokyo, Tokyo 153-8902, Japan
| | - Takashi Tsuboi
- From the Department of Life Sciences, Graduate School of Arts and Sciences, The University of Tokyo, Tokyo 153-8902, Japan,
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7
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Na SY, Kim KH, Choi MS, Ha KS, Lim DY. Gintonin facilitates catecholamine secretion from the perfused adrenal medulla. THE KOREAN JOURNAL OF PHYSIOLOGY & PHARMACOLOGY : OFFICIAL JOURNAL OF THE KOREAN PHYSIOLOGICAL SOCIETY AND THE KOREAN SOCIETY OF PHARMACOLOGY 2016; 20:629-639. [PMID: 27847440 PMCID: PMC5106397 DOI: 10.4196/kjpp.2016.20.6.629] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/10/2016] [Revised: 08/08/2016] [Accepted: 08/22/2016] [Indexed: 11/26/2022]
Abstract
The present study was designed to investigate the characteristics of gintonin, one of components isolated from Korean Ginseng on secretion of catecholamines (CA) from the isolated perfused model of rat adrenal gland and to clarify its mechanism of action. Gintonin (1 to 30 µg/ml), perfused into an adrenal vein, markedly increased the CA secretion from the perfused rat adrenal medulla in a dose-dependent fashion. The gintonin-evoked CA secretion was greatly inhibited in the presence of chlorisondamine (1 µM, an autonomic ganglionic bloker), pirenzepine (2 µM, a muscarinic M1 receptor antagonist), Ki14625 (10 µM, an LPA1/3 receptor antagonist), amiloride (1 mM, an inhibitor of Na+/Ca2+ exchanger), a nicardipine (1 µM, a voltage-dependent Ca2+ channel blocker), TMB-8 (1 µM, an intracellular Ca2+ antagonist), and perfusion of Ca2+-free Krebs solution with 5mM EGTA (a Ca2+chelater), while was not affected by sodium nitroprusside (100 µM, a nitrosovasodialtor). Interestingly, LPA (0.3~3 µM, an LPA receptor agonist) also dose-dependently enhanced the CA secretion from the adrenal medulla, but this facilitatory effect of LPA was greatly inhibited in the presence of Ki 14625 (10 µM). Moreover, acetylcholine (AC)-evoked CA secretion was greatly potentiated during the perfusion of gintonin (3 µg/ml). Taken together, these results demonstrate the first evidence that gintonin increases the CA secretion from the perfused rat adrenal medulla in a dose-dependent fashion. This facilitatory effect of gintonin seems to be associated with activation of LPA- and cholinergic-receptors, which are relevant to the cytoplasmic Ca2+ increase by stimulation of the Ca2+ influx as well as by the inhibition of Ca2+ uptake into the cytoplasmic Ca2+ stores, without the increased nitric oxide (NO). Based on these results, it is thought that gintonin, one of ginseng components, can elevate the CA secretion from adrenal medulla by regulating the Ca2+ mobilization for exocytosis, suggesting facilitation of cardiovascular system. Also, these findings show that gintonin might be at least one of ginseng-induced hypertensive components.
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Affiliation(s)
- Seung-Yeol Na
- Department of Physiology, College of Veterinary Medicine, Konkuk University, Seoul 05029, Korea
| | - Ki-Hwan Kim
- Department of Internal Medicine, School of Medicine, Boramae Seoul National University, Seoul 07061, Korea
| | - Mi-Sung Choi
- Department of Leisure & Sport, College of Public Health & Welfare, Dongshin University, Naju 58245, Korea
| | - Kang-Su Ha
- Department of Psychiatry, College of Medicine, Chosun University, Gwangju 61452, Korea
| | - Dong-Yoon Lim
- Department of Pharmacology, College of Medicine, Chosun University, Gwangju 61452, Korea
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Wu AZY, Loh SH, Cheng TH, Lu HH, Lin CI. Antiarrhythmic effects of (-)-epicatechin-3-gallate, a novel sodium channel agonist in cultured neonatal rat ventricular myocytes. Biochem Pharmacol 2012; 85:69-80. [PMID: 23116965 DOI: 10.1016/j.bcp.2012.10.003] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2012] [Revised: 09/24/2012] [Accepted: 10/01/2012] [Indexed: 02/08/2023]
Abstract
(-)-Epicatechin-3-gallate (ECG), a polyphenol extracted from green tea, has been proposed as an effective compound for improving cardiac contractility. However, the therapeutic potential of ECG on the treatment of arrhythmia remains unknown. We investigated the direct actions of ECG on the modulation of ion currents and cardiac cell excitability in the primary culture of neonatal rat ventricular myocyte (NRVM), which is considered a hypertrophic model for analysis of myocardial arrhythmias. By using the whole-cell patch-clamp configurations, we found ECG enhanced the slowly inactivating component of voltage-gated Na(+) currents (I(Na)) in a concentration-dependent manner (0.1-100 μM) with an EC(50) value of 3.8 μM. ECG not only shifted the current-voltage relationship of peak I(Na) to the hyperpolarizing direction but also accelerated I(Na) recovery kinetics. Working at a concentration level of I(Na) enhancement, ECG has no notable effect on voltage-gated K(+) currents and L-type Ca(2+) currents. With culture time increment, the firing rate of spontaneous action potential (sAP) in NRVMs was gradually decreased until spontaneous early after-depolarization (EAD) was observed after about one week culture. ECG increased the firing rate of normal sAP about two-fold without waveform alteration. Interestingly, the bradycardia-dependent EAD could be significantly restored by ECG in fast firing rate to normal sAP waveform. The expression of dominant cardiac sodium channel subunit, Nav1.5, was consistently detected throughout the culture periods. Our results reveal how ECG, the novel I(Na) agonist, may act as a promising candidate in clinical applications on cardiac arrhythmias.
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Affiliation(s)
- Adonis Zhi-Yang Wu
- Graduate Institute of Life Sciences, National Defense Medical Center, Taipei, Taiwan, ROC
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9
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Chang KS, Sun CJ, Chiang PL, Chou AC, Lin MC, Liang C, Hung HH, Yeh YH, Chen CD, Pan CY, Chen YT. Monitoring extracellular K+ flux with a valinomycin-coated silicon nanowire field-effect transistor. Biosens Bioelectron 2011; 31:137-43. [PMID: 22036669 DOI: 10.1016/j.bios.2011.10.005] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2011] [Revised: 10/02/2011] [Accepted: 10/05/2011] [Indexed: 01/13/2023]
Abstract
A silicon nanowire field-effect transistor (SiNW-FET) coated with a polyvinyl chloride (PVC) membrane containing valinomycin (VAL) was employed as a biosensor (referred to as VAL-PVC/SiNW-FET) to detect the K(+)-efflux from live chromaffin cells. The detection sensitivity of K(+) with the VAL-PVC/SiNW-FET covers a broad range of concentrations from 10(-6) to 10(-2) M. The apparent association constants between VAL and Li(+), Na(+), K(+), and Cs(+) in Tris buffer solution were determined to be 67±42, 120±23, 5974±115, and 4121±140 M(-1), respectively. By culturing chromaffin cells on the VAL-PVC/SiNW-FET, the conductance was significantly increased by nicotine stimulation in a bath buffer without Na(+). The K(+) concentration at the cell surface was determined to be ~20 μM under the stimulation of 5 mM nicotine. These results demonstrate that the VAL-PVC/SiNW-FET is sensitive and selective to detect the released K(+) from cells and is suitable for applications in cellular recording investigations.
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Affiliation(s)
- Ko-Shing Chang
- Department of Chemistry, National Taiwan University, Taipei 106, Taiwan
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10
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Trimbuch T, Beed P, Vogt J, Schuchmann S, Maier N, Kintscher M, Breustedt J, Schuelke M, Streu N, Kieselmann O, Brunk I, Laube G, Strauss U, Battefeld A, Wende H, Birchmeier C, Wiese S, Sendtner M, Kawabe H, Kishimoto-Suga M, Brose N, Baumgart J, Geist B, Aoki J, Savaskan NE, Bräuer AU, Chun J, Ninnemann O, Schmitz D, Nitsch R. Synaptic PRG-1 modulates excitatory transmission via lipid phosphate-mediated signaling. Cell 2009; 138:1222-35. [PMID: 19766573 DOI: 10.1016/j.cell.2009.06.050] [Citation(s) in RCA: 107] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2008] [Revised: 04/30/2009] [Accepted: 06/19/2009] [Indexed: 11/27/2022]
Abstract
Plasticity related gene-1 (PRG-1) is a brain-specific membrane protein related to lipid phosphate phosphatases, which acts in the hippocampus specifically at the excitatory synapse terminating on glutamatergic neurons. Deletion of prg-1 in mice leads to epileptic seizures and augmentation of EPSCs, but not IPSCs. In utero electroporation of PRG-1 into deficient animals revealed that PRG-1 modulates excitation at the synaptic junction. Mutation of the extracellular domain of PRG-1 crucial for its interaction with lysophosphatidic acid (LPA) abolished the ability to prevent hyperexcitability. As LPA application in vitro induced hyperexcitability in wild-type but not in LPA(2) receptor-deficient animals, and uptake of phospholipids is reduced in PRG-1-deficient neurons, we assessed PRG-1/LPA(2) receptor-deficient animals, and found that the pathophysiology observed in the PRG-1-deficient mice was fully reverted. Thus, we propose PRG-1 as an important player in the modulatory control of hippocampal excitability dependent on presynaptic LPA(2) receptor signaling.
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Affiliation(s)
- Thorsten Trimbuch
- Institute of Cell Biology and Neurobiology and NeuroCure, Charité, Universitätsmedizin Berlin, Berlin, Germany
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11
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Shih PY, Lin CL, Cheng PW, Liao JH, Pan CY. Calneuron I inhibits Ca(2+) channel activity in bovine chromaffin cells. Biochem Biophys Res Commun 2009; 388:549-53. [PMID: 19682431 DOI: 10.1016/j.bbrc.2009.08.046] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2009] [Accepted: 08/07/2009] [Indexed: 10/20/2022]
Abstract
Calneuron I (CalnI) is a calmodulin-like protein that contains two functional EF-hand motifs at the N-terminal and a hydrophobic segment at the C-terminal. CalnI was cloned from the adult rat cortex and fused with GFP at its N-terminal. When expressed in bovine chromaffin cells, wild-type CalnI was localized at the plasma membrane. However, a mutant that lacked the hydrophobic segment was localized in the cytosol and nucleus, while a Ca(2+)-binding-deficient mutant was found in the cytosol and at the plasma membrane. Evaluation using the whole-cell patch-clamp technique revealed that Ca(2+) currents were inhibited by both wild-type CalnI and the Ca(2+)-binding-deficient mutant. When the bovine N-type Ca(2+) channel was expressed in 293T cells, Ca(2+) currents were mostly inhibited by co-expression of CalnI, but not by the mutant without the hydrophobic tail. These results suggest that CalnI attenuates Ca(2+) channel activity and that its subcellular localization is important for this effect.
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Affiliation(s)
- Po-Yuan Shih
- Institute of Zoology, National Taiwan University, Taipei, Taiwan, ROC
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Effects of nonylphenol on the calcium signal and catecholamine secretion coupled with nicotinic acetylcholine receptors in bovine adrenal chromaffin cells. Toxicology 2008; 244:77-85. [DOI: 10.1016/j.tox.2007.11.005] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2007] [Revised: 10/26/2007] [Accepted: 11/07/2007] [Indexed: 11/22/2022]
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Maruta T, Yanagita T, Matsuo K, Uezono Y, Satoh S, Nemoto T, Yoshikawa N, Kobayashi H, Takasaki M, Wada A. Lysophosphatidic acid-LPA1 receptor-Rho-Rho kinase-induced up-regulation of Nav1.7 sodium channel mRNA and protein in adrenal chromaffin cells: enhancement of 22Na+ influx, 45Ca2+ influx and catecholamine secretion. J Neurochem 2007; 105:401-12. [PMID: 18036192 DOI: 10.1111/j.1471-4159.2007.05143.x] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
In cultured bovine adrenal chromaffin cells, chronic (> or = 24 h) treatment with lysophosphatidic acid (LPA) augmented veratridine-induced 22Na+ influx via Na(v)1.7 by approximately 22% (EC(50) = 1 nmol/L), without changing nicotine-induced 22Na+ influx via nicotinic receptor-associated channel. LPA enhanced veratridine (but not nicotine)-induced 45Ca2+ influx via voltage-dependent calcium channel and catecholamine secretion. LPA shifted concentration-response curve of veratridine for 22Na+ influx upward, without altering the EC(50) of veratridine. Ptychodiscus brevis toxin-3 allosterically enhanced veratridine-induced 22Na+ influx by twofold in non-treated and LPA-treated cells. Whole-cell patch-clamp analysis showed that peak Na+ current amplitude was greater by 39% in LPA (100 nmol/L for 36 h)-treated cells; however, I-V curve and steady-state inactivation/activation curves were comparable between non-treated and LPA-treated cells. LPA treatment (> or = 24 h) increased cell surface [3H]saxitoxin binding by approximately 28%, without altering the K(d) value; the increase was prevented by cycloheximide, actinomycin D, or Ki16425, dioctylglycerol pyrophosphate 8:0 (two inhibitors of LPA(1) and LPA3 receptors), or botulinum toxin C3 (Rho inhibitor), Y27632 (Rho kinase inhibitor), consistent with LPA(1) receptor expression in adrenal chromaffin cells. LPA raised Nav1.7 mRNA level by approximately 37%. Thus, LPA-LPA(1) receptor-Rho/Rho kinase pathway up-regulated cell surface Nav1.7 and Nav1.7 mRNA levels, enhancing veratridine-induced Ca2+ influx and catecholamine secretion.
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Affiliation(s)
- Toyoaki Maruta
- Departments of Pharmacology, and Anesthesiology, Miyazaki Medical College, University of Miyazaki, Miyazaki, Japan
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