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McCracken NA, Liu H, Runnebohm AM, Wijeratne HRS, Wijeratne AB, Staschke KA, Mosley AL. Obtaining Functional Proteomics Insights From Thermal Proteome Profiling Through Optimized Melt Shift Calculation and Statistical Analysis With InflectSSP. Mol Cell Proteomics 2023; 22:100630. [PMID: 37562535 PMCID: PMC10494267 DOI: 10.1016/j.mcpro.2023.100630] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2022] [Revised: 07/20/2023] [Accepted: 08/03/2023] [Indexed: 08/12/2023] Open
Abstract
Thermal proteome profiling (TPP) is an invaluable tool for functional proteomics studies that has been shown to discover changes associated with protein-ligand, protein-protein, and protein-RNA interaction dynamics along with changes in protein stability resulting from cellular signaling. The increasing number of reports employing this assay has not been met concomitantly with new approaches leading to advancements in the quality and sensitivity of the corresponding data analysis. The gap between data acquisition and data analysis tools is important to fill as TPP findings have reported subtle melt shift changes related to signaling events such as protein posttranslational modifications. In this study, we have improved the Inflect data analysis pipeline (now referred to as InflectSSP, available at https://CRAN.R-project.org/package=InflectSSP) to increase the sensitivity of detection for both large and subtle changes in the proteome as measured by TPP. Specifically, InflectSSP now has integrated statistical and bioinformatic functions to improve objective functional proteomics findings from the quantitative results obtained from TPP studies through increasing both the sensitivity and specificity of the data analysis pipeline. InflectSSP incorporates calculation of a "melt coefficient" into the pipeline with production of average melt curves for biological replicate studies to aid in identification of proteins with significant melts. To benchmark InflectSSP, we have reanalyzed two previously reported datasets to demonstrate the performance of our publicly available R-based program for TPP data analysis. We report new findings following temporal treatment of human cells with the small molecule thapsigargin that induces the unfolded protein response as a consequence of inhibition of sarcoplasmic/endoplasmic reticulum calcium ATPase 2A. InflectSSP analysis of our unfolded protein response study revealed highly reproducible and statistically significant target engagement over a time course of treatment while simultaneously providing new insights into the possible mechanisms of action of the small molecule thapsigargin.
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Affiliation(s)
- Neil A McCracken
- Department of Biochemistry and Molecular Biology, Indiana University School of Medicine, Indianapolis, Indiana, United States
| | - Hao Liu
- Biostatistics and Health Data Science, Indiana University School of Medicine, Indianapolis, Indiana, United States; Department of Biostatistics and Epidemiology, Rutgers School of Public Health, Piscataway, New Jersey, United States
| | - Avery M Runnebohm
- Department of Biochemistry and Molecular Biology, Indiana University School of Medicine, Indianapolis, Indiana, United States
| | - H R Sagara Wijeratne
- Department of Biochemistry and Molecular Biology, Indiana University School of Medicine, Indianapolis, Indiana, United States
| | - Aruna B Wijeratne
- Department of Biochemistry and Molecular Biology, Indiana University School of Medicine, Indianapolis, Indiana, United States
| | - Kirk A Staschke
- Department of Biochemistry and Molecular Biology, Indiana University School of Medicine, Indianapolis, Indiana, United States
| | - Amber L Mosley
- Department of Biochemistry and Molecular Biology, Indiana University School of Medicine, Indianapolis, Indiana, United States; Center for Computational Biology and Bioinformatics, Indiana University School of Medicine, Indianapolis, Indiana, USA.
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2
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Steiner JP, Bachani M, Malik N, DeMarino C, Li W, Sampson K, Lee M, Kowalak J, Bhaskar M, Doucet‐O'Hare T, Garcia‐Montojo M, Cowen M, Smith B, Reoma LB, Medina J, Brunel J, Pierquin J, Charvet B, Perron H, Nath A. Human Endogenous Retrovirus K Envelope in Spinal Fluid of Amyotrophic Lateral Sclerosis Is Toxic. Ann Neurol 2022; 92:545-561. [PMID: 35801347 PMCID: PMC9489628 DOI: 10.1002/ana.26452] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2021] [Revised: 07/02/2022] [Accepted: 07/05/2022] [Indexed: 12/30/2022]
Abstract
OBJECTIVE Human endogenous retroviruses have been implicated in neurodegenerative diseases including amyotrophic lateral sclerosis (ALS). Expression of human endogenous retrovirus K (HERV-K) subtype HML-2 envelope (Env) in human neuronal cultures and in transgenic mice results in neurotoxicity and neurodegeneration, and mice expressing HML-2 Env display behavioral and neuromuscular characteristics resembling ALS. This study aims to characterize the neurotoxic properties of HML-2 Env. METHODS Env neurotoxicity was detected in ALS cerebrospinal fluid and confirmed using recombinant Env protein in a cell-based assay and a mouse model. The mechanism of neurotoxicity was assessed with immunoprecipitation followed by mass spectrometry and Western blot, and by screening a panel of inhibitors. RESULTS We observed that recombinant HML-2 Env protein caused neurotoxicity resulting in neuronal cell death, retraction of neurites, and decreased neuronal electrical activity. Injection of the Env protein into the brains of mice also resulted in neuronal cell death. HML-2 Env protein was also found in the cerebrospinal fluid of patients with sporadic ALS. The neurotoxic properties of the Env and the cerebrospinal fluid could be rescued with the anti-Env antibody. The Env was found to bind to CD98HC complexed to β1 integrin on the neuronal cell surface. Using a panel of compounds to screen for their ability to block Env-induced neurotoxicity, we found that several compounds were protective and are linked to the β1 integrin pathway. INTERPRETATION HERV-K Env is released extracellularly in ALS and causes neurotoxicity via a novel mechanism. Present results pave the way for new treatment strategies in sporadic ALS. ANN NEUROL 2022;92:545-561.
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Affiliation(s)
- Joseph P. Steiner
- NeuroTherapeutics Development Unit, Translational Neuroscience Center, National Institute of Neurological Disorders and StrokeNational Institutes of HealthBethesdaMDUSA
| | - Muzna Bachani
- NeuroTherapeutics Development Unit, Translational Neuroscience Center, National Institute of Neurological Disorders and StrokeNational Institutes of HealthBethesdaMDUSA
| | - Nasir Malik
- NeuroTherapeutics Development Unit, Translational Neuroscience Center, National Institute of Neurological Disorders and StrokeNational Institutes of HealthBethesdaMDUSA
| | - Catherine DeMarino
- Section for Infections of the Nervous System, National Institute of Neurological Disorders and StrokeNational Institutes of HealthBethesdaMDUSA
| | - Wenxue Li
- Section for Infections of the Nervous System, National Institute of Neurological Disorders and StrokeNational Institutes of HealthBethesdaMDUSA
| | - Kevon Sampson
- Section for Infections of the Nervous System, National Institute of Neurological Disorders and StrokeNational Institutes of HealthBethesdaMDUSA
| | - Myoung‐Hwa Lee
- Section for Infections of the Nervous System, National Institute of Neurological Disorders and StrokeNational Institutes of HealthBethesdaMDUSA
| | - Jeffery Kowalak
- Clinical Proteomics Unit, Translational Neuroscience Center, National Institute of Neurological Disorders and StrokeNational Institutes of HealthBethesdaMDUSA
| | - Manju Bhaskar
- NeuroTherapeutics Development Unit, Translational Neuroscience Center, National Institute of Neurological Disorders and StrokeNational Institutes of HealthBethesdaMDUSA
| | - Tara Doucet‐O'Hare
- Section for Infections of the Nervous System, National Institute of Neurological Disorders and StrokeNational Institutes of HealthBethesdaMDUSA
| | - Marta Garcia‐Montojo
- Section for Infections of the Nervous System, National Institute of Neurological Disorders and StrokeNational Institutes of HealthBethesdaMDUSA
| | - Maria Cowen
- Section for Infections of the Nervous System, National Institute of Neurological Disorders and StrokeNational Institutes of HealthBethesdaMDUSA
| | - Bryan Smith
- Section for Infections of the Nervous System, National Institute of Neurological Disorders and StrokeNational Institutes of HealthBethesdaMDUSA
| | - Lauren Bowen Reoma
- Section for Infections of the Nervous System, National Institute of Neurological Disorders and StrokeNational Institutes of HealthBethesdaMDUSA
| | | | | | | | | | - Hervé Perron
- R&D divisionGeNeuro InnovationLyonFrance,GeNeuroPlan‐les‐OuatesSwitzerland
| | - Avindra Nath
- Section for Infections of the Nervous System, National Institute of Neurological Disorders and StrokeNational Institutes of HealthBethesdaMDUSA
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3
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Lv W, Wang X, Xu Q, Lu W. Mechanisms and Characteristics of Sulfonylureas and Glinides. Curr Top Med Chem 2020; 20:37-56. [PMID: 31884929 DOI: 10.2174/1568026620666191224141617] [Citation(s) in RCA: 44] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2019] [Revised: 08/30/2019] [Accepted: 09/22/2019] [Indexed: 12/25/2022]
Abstract
BACKGROUND Type 2 diabetes mellitus is a complex progressive endocrine disease characterized by hyperglycemia and life-threatening complications. It is the most common disorder of pancreatic cell function that causes insulin deficiency. Sulfonylurea is a class of oral hypoglycemic drugs. Over the past half century, these drugs, together with the subsequent non-sulfonylureas (glinides), have been the main oral drugs for insulin secretion. OBJECTIVE Through in-depth study, the medical profession considers it as an important drug for improving blood sugar control. METHODS The mechanism, characteristics, efficacy and side effects of sulfonylureas and glinides were reviewed in detail. RESULTS Sulfonylureas and glinides not only stimulated the release of insulin from pancreatic cells, but also had many extrapanular hypoglycemic effect, such as reducing the clearance rate of insulin in liver, reducing the secretion of glucagon, and enhancing the sensitivity of peripheral tissues to insulin in type 2 diabetes mellitus. CONCLUSION Sulfonylureas and glinides are effective first-line drugs for the treatment of diabetes mellitus. Although they have the risk of hypoglycemia, weight gain and cardiovascular disease, their clinical practicability and safety can be guaranteed as long as they are reasonably used.
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Affiliation(s)
- Wei Lv
- School of Materials Science and Engineering, Shanghai University, Shanghai, China.,Shanghai Huayi Resins Co., Ltd., Shanghai, China
| | - Xianqing Wang
- Charles Institute of Dermatology, University College Dublin, Dublin D04 V1W8, Ireland
| | - Qian Xu
- Charles Institute of Dermatology, University College Dublin, Dublin D04 V1W8, Ireland
| | - Wencong Lu
- School of Materials Science and Engineering, Shanghai University, Shanghai, China
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Maejima Y. SGLT2 Inhibitors Play a Salutary Role in Heart Failure via Modulation of the Mitochondrial Function. Front Cardiovasc Med 2020; 6:186. [PMID: 31970162 PMCID: PMC6960132 DOI: 10.3389/fcvm.2019.00186] [Citation(s) in RCA: 62] [Impact Index Per Article: 15.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2019] [Accepted: 12/10/2019] [Indexed: 01/10/2023] Open
Abstract
Three cardiovascular outcome trials of sodium glucose cotransporter 2 (SGLT2) inhibitors, including the EMPA-REG OUTCOME trial, CANVAS Program, and DECLARE TIMI 58 trial, revealed that SGLT2 inhibitors were superior to a matching placebo in reducing cardiovascular events, including mortality and hospitalization for heart failure, in patients with type 2 diabetes. However, the detailed mechanism underlying the beneficial effects that SGLT2 inhibitors exert on cardiovascular diseases remains to be elucidated. We herein review the latest findings of the salutary mechanisms of SGLT2 inhibitors in cardiomyocytes, especially focusing on their mitochondrial function-mediated beneficial effects. The administration of SGLT2 inhibitors leads to the elevation of plasma levels of ketone bodies, which are an efficient energy source in the failing heart, by promoting oxidation of the mitochondrial coenzyme Q couple and enhancing the free energy of cytosolic ATP hydrolysis. SGLT2 inhibitors also promote sodium metabolism-mediated cardioprotective effects. These compounds could reduce the intracellular sodium overload to improve mitochondrial energetics and oxidative defense in the heart through binding with NHE and/or SMIT1. Furthermore, SGLT2 inhibitors could modulate mitochondrial dynamics by regulating the fusion and fission of mitochondria. Together with ongoing large-scale clinical trials to evaluate the efficacy of SGLT2 inhibitors in patients with heart failure, intensive investigations regarding the mechanism through which SGLT2 inhibitors promote the restoration in cases of heart failure would lead to the establishment of these drugs as potent anti-heart failure drugs.
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Affiliation(s)
- Yasuhiro Maejima
- Department of Cardiovascular Medicine, Tokyo Medical and Dental University, Tokyo, Japan
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5
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Héja L, Simon Á, Szabó Z, Kardos J. Feedback adaptation of synaptic excitability via Glu:Na + symport driven astrocytic GABA and Gln release. Neuropharmacology 2019; 161:107629. [PMID: 31103619 DOI: 10.1016/j.neuropharm.2019.05.006] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2018] [Revised: 03/30/2019] [Accepted: 05/07/2019] [Indexed: 02/08/2023]
Abstract
Glutamatergic transmission composed of the arriving of action potential at the axon terminal, fast vesicular Glu release, postsynaptic Glu receptor activation, astrocytic Glu clearance and Glu→Gln shuttle is an abundantly investigated phenomenon. Despite its essential role, however, much less is known about the consequences of the mechanistic connotations of Glu:Na+ symport. Due to the coupled Na+ transport, Glu uptake results in significantly elevated intracellular astrocytic [Na+] that markedly alters the driving force of other Na+-coupled astrocytic transporters. The resulting GABA and Gln release by reverse transport through the respective GAT-3 and SNAT3 transporters help to re-establish the physiological Na+ homeostasis without ATP dissipation and consequently leads to enhanced tonic inhibition and replenishment of axonal glutamate pool. Here, we place this emerging astrocytic adjustment of synaptic excitability into the centre of future perspectives. This article is part of the issue entitled 'Special Issue on Neurotransmitter Transporters'.
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Affiliation(s)
- László Héja
- Functional Pharmacology Research Group, Institute of Organic Chemistry, Research Centre for Natural Sciences, Hungarian Academy of Sciences, Magyar tudósok körútja 2, 1117, Budapest, Hungary
| | - Ágnes Simon
- Functional Pharmacology Research Group, Institute of Organic Chemistry, Research Centre for Natural Sciences, Hungarian Academy of Sciences, Magyar tudósok körútja 2, 1117, Budapest, Hungary
| | - Zsolt Szabó
- Functional Pharmacology Research Group, Institute of Organic Chemistry, Research Centre for Natural Sciences, Hungarian Academy of Sciences, Magyar tudósok körútja 2, 1117, Budapest, Hungary
| | - Julianna Kardos
- Functional Pharmacology Research Group, Institute of Organic Chemistry, Research Centre for Natural Sciences, Hungarian Academy of Sciences, Magyar tudósok körútja 2, 1117, Budapest, Hungary.
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6
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Floyd CN, Lidder S, Hunt J, Omar SA, McNeill K, Webb AJ. Acute interaction between oral glucose (75 g as Lucozade) and inorganic nitrate: Decreased insulin clearance, but lack of blood pressure-lowering. Br J Clin Pharmacol 2019; 85:1443-1453. [PMID: 30845346 DOI: 10.1111/bcp.13913] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2018] [Revised: 02/08/2019] [Accepted: 03/03/2019] [Indexed: 11/28/2022] Open
Abstract
AIMS Dietary inorganic nitrate (NO3 - ) lowers peripheral blood pressure (BP) in healthy volunteers, but lacks such effect in individuals with, or at risk of, type 2 diabetes mellitus (T2DM). Whilst this is commonly assumed to be a consequence of chronic hyperglycaemia/hyperinsulinaemia, we hypothesized that acute physiological elevations in plasma [glucose]/[insulin] blunt the haemodynamic responses to NO3 - , a pertinent question for carbohydrate-rich Western diets. METHODS We conducted an acute, randomized, placebo-controlled, double-blind, crossover study on the haemodynamic and metabolic effects of potassium nitrate (8 or 24 mmol KNO3 ) vs. potassium chloride (KCl; placebo) administered 1 hour prior to an oral glucose tolerance test in 33 healthy volunteers. RESULTS Compared to placebo, there were no significant differences in systolic or diastolic BP (P = 0.27 and P = 0.30 on ANOVA, respectively) with KNO3 , nor in pulse wave velocity or central systolic BP (P = 0.99 and P = 0.54 on ANOVA, respectively). Whilst there were significant elevations from baseline for plasma [glucose] and [C-peptide], no differences between interventions were observed. A significant increase in plasma [insulin] was observed with KNO3 vs. KCl (n = 33; P = 0.014 on ANOVA) with the effect driven by the high-dose cohort (24 mmol, n = 13; P < 0.001 on ANOVA; at T = 0.75 h mean difference 210.4 pmol/L (95% CI 28.5 to 392.3), P = 0.012). CONCLUSIONS In healthy adults, acute physiological elevations of plasma [glucose] and [insulin] result in a lack of BP-lowering with dietary nitrate. The increase in plasma [insulin] without a corresponding change in [C-peptide] or [glucose] suggests that high-dose NO3 - decreases insulin clearance. A likely mechanism is via NO-dependent inhibition of insulin-degrading enzyme.
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Affiliation(s)
- Christopher N Floyd
- School of Cardiovascular Medicine and Sciences, Department of Clinical Pharmacology, King's College London British Heart Foundation Centre, London, UK.,Biomedical Research Centre, Clinical Research Facility, Guy's and St Thomas' NHS Foundation Trust, London, UK
| | - Satnam Lidder
- School of Cardiovascular Medicine and Sciences, Department of Clinical Pharmacology, King's College London British Heart Foundation Centre, London, UK.,Biomedical Research Centre, Clinical Research Facility, Guy's and St Thomas' NHS Foundation Trust, London, UK
| | - Joanne Hunt
- School of Cardiovascular Medicine and Sciences, Department of Clinical Pharmacology, King's College London British Heart Foundation Centre, London, UK.,Biomedical Research Centre, Clinical Research Facility, Guy's and St Thomas' NHS Foundation Trust, London, UK
| | - Sami A Omar
- School of Cardiovascular Medicine and Sciences, Department of Clinical Pharmacology, King's College London British Heart Foundation Centre, London, UK.,Biomedical Research Centre, Clinical Research Facility, Guy's and St Thomas' NHS Foundation Trust, London, UK
| | - Karen McNeill
- School of Cardiovascular Medicine and Sciences, Department of Clinical Pharmacology, King's College London British Heart Foundation Centre, London, UK.,Biomedical Research Centre, Clinical Research Facility, Guy's and St Thomas' NHS Foundation Trust, London, UK
| | - Andrew J Webb
- School of Cardiovascular Medicine and Sciences, Department of Clinical Pharmacology, King's College London British Heart Foundation Centre, London, UK.,Biomedical Research Centre, Clinical Research Facility, Guy's and St Thomas' NHS Foundation Trust, London, UK
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Tsai MC, Huang TL. Orexin A in men with heroin use disorder undergoing methadone maintenance treatment. Psychiatry Res 2018; 264:412-415. [PMID: 29680730 DOI: 10.1016/j.psychres.2018.04.010] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/15/2017] [Revised: 04/02/2018] [Accepted: 04/02/2018] [Indexed: 12/16/2022]
Abstract
Orexins have played a role in reward-seeking and addiction-related behavior. There are few reports in the literature on serum levels of orexins in patients with heroin use disorder (HUD) undergoing methadone maintenance treatment (MMT). The aim of this study was to investigate the serum levels of orexin A in HUD patients undergoing MMT. Fifty male HUD patients undergoing MMT and 25 healthy males were enrolled for this study. Serum orexin A were measured with assay kits. Using analysis of covariance (ANCOVA) with body mass index (BMI) adjustments, the serum levels of orexin A in HUD men undergoing MMT were found to be significantly higher than in healthy controls. In conclusion, our results suggest that MMT might increase orexin A levels in HUD patients.
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Affiliation(s)
- Meng-Chang Tsai
- Department of Psychiatry, Kaohsiung Chang Gung Memorial Hospital and Chang Gung University College of Medicine, Kaohsiung, Taiwan, ROC
| | - Tiao-Lai Huang
- Department of Psychiatry, Kaohsiung Chang Gung Memorial Hospital and Chang Gung University College of Medicine, Kaohsiung, Taiwan, ROC.
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8
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Łupina M, Tarnowski M, Baranowska-Bosiacka I, Talarek S, Listos P, Kotlińska J, Gutowska I, Listos J. SB-334867 (an Orexin-1 Receptor Antagonist) Effects on Morphine-Induced Sensitization in Mice-a View on Receptor Mechanisms. Mol Neurobiol 2018; 55:8473-8485. [PMID: 29557083 PMCID: PMC6153720 DOI: 10.1007/s12035-018-0993-0] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2017] [Accepted: 03/07/2018] [Indexed: 12/20/2022]
Abstract
The present study focused upon the role of SB-334867, an orexin-1 receptor antagonist, in the acquisition of morphine-induced sensitization to locomotor activity in mice. Behavioral sensitization is an enhanced systemic reaction to the same dose of an addictive substance, which assumingly increases both the desire for the drug and the risk of relapse to addiction. Morphine-induced sensitization in mice was achieved by sporadic doses (five injections every 3 days) of morphine (10 mg/kg, i.p.), while a challenge dose of morphine (10 mg/kg) was injected 7 days later. In order to assess the impact of orexin system blockade on the acquisition of sensitization, SB-334867 was administered before each morphine injection, except the morphine challenge dose. The locomotor activity test was performed on each day of morphine administration. Brain structures (striatum, hippocampus, and prefrontal cortex) were collected after behavioral tests for molecular experiments in which mRNA expression of orexin, dopamine, and adenosine receptors was explored by the qRT-PCR technique. Additionally, the mRNA expression of markers, such as GFAP and Iba-1, was also analyzed by the same technique. SB-334867 inhibited the acquisition of morphine-induced sensitization to locomotor activity of mice. Significant alterations were observed in mRNA expression of orexin, dopamine, and adenosine receptors and in the expression of GFAP and Iba-1, showing a broad range of interactions in the mesolimbic system among orexin, dopamine, adenosine, and glial cells during behavioral sensitization. Summing up, the orexin system may be an effective measure to inhibit morphine-induced behavioral sensitization.
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Affiliation(s)
- Małgorzata Łupina
- Department of Pharmacology and Pharmacodynamics, Medical University of Lublin, Chodźki 4a St., 20-093, Lublin, Poland.
| | - Maciej Tarnowski
- Department of Physiology, Pomeranian Medical University, Powstańców Wlkp. 72 Av., 70-111, Szczecin, Poland
| | - Irena Baranowska-Bosiacka
- Department of Biochemistry and Medical Chemistry, Pomeranian Medical University, Powstańców Wlkp. 72 Av., 70-111, Szczecin, Poland
| | - Sylwia Talarek
- Department of Pharmacology and Pharmacodynamics, Medical University of Lublin, Chodźki 4a St., 20-093, Lublin, Poland
| | - Piotr Listos
- Department and Clinic of Animal Internal Diseases, Sub-Department of Pathomorphology and Forensic Medicine, Faculty of Veterinary Medicine, University of Life Sciences in Lublin, 30 Av, 20-612, Lublin, Poland
| | - Jolanta Kotlińska
- Department of Pharmacology and Pharmacodynamics, Medical University of Lublin, Chodźki 4a St., 20-093, Lublin, Poland
| | - Izabela Gutowska
- Department of Biochemistry and Human Nutrition, Pomeranian Medical University, Broniewskiego 24 Str., 71-460, Szczecin, Poland
| | - Joanna Listos
- Department of Pharmacology and Pharmacodynamics, Medical University of Lublin, Chodźki 4a St., 20-093, Lublin, Poland
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9
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Barthmes M, Liao J, Jiang Y, Brüggemann A, Wahl-Schott C. Electrophysiological characterization of the archaeal transporter NCX_Mj using solid supported membrane technology. J Gen Physiol 2017; 147:485-96. [PMID: 27241699 PMCID: PMC4886279 DOI: 10.1085/jgp.201611587] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2016] [Accepted: 05/11/2016] [Indexed: 01/24/2023] Open
Abstract
NCX_Mj is a sodium–calcium exchanger from the archaebacterium Methanococcus jannaschii, whose crystal structure has been solved. Barthmes et al. use solid supported membrane–based electrophysiology to characterize NCX_Mj and reveal its functional similarity to eukaryotic isoforms. Sodium–calcium exchangers (NCXs) are membrane transporters that play an important role in Ca2+ homeostasis and Ca2+ signaling. The recent crystal structure of NCX_Mj, a member of the NCX family from the archaebacterium Methanococcus jannaschii, provided insight into the atomistic details of sodium–calcium exchange. Here, we extend these findings by providing detailed functional data on purified NCX_Mj using solid supported membrane (SSM)–based electrophysiology, a powerful but unexploited tool for functional studies of electrogenic transporter proteins. We show that NCX_Mj is highly selective for Na+, whereas Ca2+ can be replaced by Mg2+ and Sr2+ and that NCX_Mj can be inhibited by divalent ions, particularly Cd2+. By directly comparing the apparent affinities of Na+ and Ca2+ for NCX_Mj with those for human NCX1, we show excellent agreement, indicating a strong functional similarity between NCX_Mj and its eukaryotic isoforms. We also provide detailed instructions to facilitate the adaption of this method to other electrogenic transporter proteins. Our findings demonstrate that NCX_Mj can serve as a model for the NCX family and highlight several possible applications for SSM-based electrophysiology.
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Affiliation(s)
- Maria Barthmes
- Nanion Technologies, 80636 Munich, Germany Center for Integrated Protein Science (CIPS-M) and Center for Drug Research, Department of Pharmacology, Ludwig Maximilians University and DZHK (German Center for Cardiovascular Research), partner site Munich Heart Alliance, 81377 Munich, Germany
| | - Jun Liao
- Department of Physiology, University of Texas Southwestern Medical Center, Dallas, TX 75390 School of Life Science and Technology, Shanghai Tech University, Shanghai 201210, China
| | - Youxing Jiang
- Department of Physiology, University of Texas Southwestern Medical Center, Dallas, TX 75390 Howard Hughes Medical Institute, University of Texas Southwestern Medical Center, Dallas, TX 75390
| | | | - Christian Wahl-Schott
- Center for Integrated Protein Science (CIPS-M) and Center for Drug Research, Department of Pharmacology, Ludwig Maximilians University and DZHK (German Center for Cardiovascular Research), partner site Munich Heart Alliance, 81377 Munich, Germany
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10
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Han J, Lee SH, Giebisch G, Wang T. Potassium Channelopathies and Gastrointestinal Ulceration. Gut Liver 2017; 10:881-889. [PMID: 27784845 PMCID: PMC5087926 DOI: 10.5009/gnl15414] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/25/2015] [Revised: 10/14/2015] [Accepted: 10/20/2015] [Indexed: 12/13/2022] Open
Abstract
Potassium channels and transporters maintain potassium homeostasis and play significant roles in several different biological actions via potassium ion regulation. In previous decades, the key revelations that potassium channels and transporters are involved in the production of gastric acid and the regulation of secretion in the stomach have been recognized. Drugs used to treat peptic ulceration are often potassium transporter inhibitors. It has also been reported that potassium channels are involved in ulcerative colitis. Direct toxicity to the intestines from nonsteroidal anti-inflammatory drugs has been associated with altered potassium channel activities. Several reports have indicated that the long-term use of the antianginal drug Nicorandil, an adenosine triphosphate-sensitive potassium channel opener, increases the chances of ulceration and perforation from the oral to anal regions throughout the gastrointestinal (GI) tract. Several of these drug features provide further insights into the role of potassium channels in the occurrence of ulceration in the GI tract. The purpose of this review is to investigate whether potassium channelopathies are involved in the mechanisms responsible for ulceration that occurs throughout the GI tract.
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Affiliation(s)
- Jaeyong Han
- Department of Cellular and Molecular Physiology, Yale University, New Haven, CT, USA
| | - Seung Hun Lee
- Department of Internal Medicine, Section of Nephrology, Yale University, New Haven, CT, USA
| | - Gerhard Giebisch
- Department of Cellular and Molecular Physiology, Yale University, New Haven, CT, USA
| | - Tong Wang
- Department of Cellular and Molecular Physiology, Yale University, New Haven, CT, USA
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11
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Piert M, Shao X, Raffel D, Davenport MS, Montgomery J, Kunju LP, Hockley BG, Siddiqui J, Scott PJH, Chinnaiyan AM, Rajendiran T. Preclinical Evaluation of 11C-Sarcosine as a Substrate of Proton-Coupled Amino Acid Transporters and First Human Application in Prostate Cancer. J Nucl Med 2017; 58:1216-1223. [PMID: 28302759 DOI: 10.2967/jnumed.116.173179] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2016] [Accepted: 02/14/2017] [Indexed: 12/14/2022] Open
Abstract
Sarcosine is a known substrate of proton-coupled amino acid transporters (PATs), which are overexpressed in selected tissues and solid tumors. Sarcosine, an N-methyl derivative of the amino acid glycine and a metabolic product of choline, plays an important role for prostate cancer aggressiveness and progression. Methods:11C-radiolabeled sarcosine was tested as a new PET imaging probe in comparison with 11C-choline in 2 prostate cancer tumor xenograft models (DU-145 and PC-3). We characterized 11C-sarcosine transport in PC-3 and LNCaP tumor cells and performed 11C-sarcosine PET with CT in the first human subject with localized Gleason 4 + 3 prostate cancer. Target metabolite analyses of sarcosine and its natural precursors, glycine and choline, were performed from independent human prostate tissues. Results: In vitro assays indicated blockage of 11C-sarcosine uptake into PC-3 and LNCaP tumor cells by excess unlabeled (cold) sarcosine. 5-hydroxy-l-tryptophan, but not 2-aminobicyclo-(2,2,1)-heptane-2-carboxylic acid, competitively inhibited 11C-sarcosine tumor cell uptake, confirming PAT-mediated transport. In vivo tumor-to-background ratios (TBRs) obtained from 11C-sarcosine PET were significantly elevated compared with 11C-choline in DU-145 (TBR: 1.92 ± 0.11 for 11C-sarcosine vs. 1.41 ± 0.13 for 11C-choline [n = 10; P < 0.002]) and PC-3 tumors (TBR: 1.89 ± 0.2 for 11C-sarcosine vs. 1.34 ± 0.16 for 11C-choline [n = 7; P < 0.002]). 11C-sarcosine produced high-contrast images in 1 case of localized clinically significant prostate cancer. Target metabolite analyses revealed significant stepwise increases of sarcosine, glycine, and choline tissue levels from benign prostate tissue to localized prostate cancer and subsequently metastatic disease. 11C-sarcosine showed a favorable radiation dosimetry with an effective dose estimate of 0.0045 mSv/MBq, resulting in 2.68 mSv for a human subject (600-MBq dose). Conclusion:11C-sarcosine is a novel radiotracer for PATs and shows initial utility for prostate cancer imaging, with potential benefit over commonly used 11C-choline.
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Affiliation(s)
- Morand Piert
- Department of Radiology, University of Michigan, Ann Arbor, Michigan
| | - Xia Shao
- Department of Radiology, University of Michigan, Ann Arbor, Michigan
| | - David Raffel
- Department of Radiology, University of Michigan, Ann Arbor, Michigan
| | | | | | | | - Brian G Hockley
- Department of Radiology, University of Michigan, Ann Arbor, Michigan
| | - Javed Siddiqui
- Pathology Department, University of Michigan, Ann Arbor, Michigan; and.,Michigan Center for Translational Pathology, University of Michigan, Ann Arbor, Michigan
| | - Peter J H Scott
- Department of Radiology, University of Michigan, Ann Arbor, Michigan
| | - Arul M Chinnaiyan
- Pathology Department, University of Michigan, Ann Arbor, Michigan; and.,Michigan Center for Translational Pathology, University of Michigan, Ann Arbor, Michigan
| | - Thekkelnaycke Rajendiran
- Pathology Department, University of Michigan, Ann Arbor, Michigan; and.,Michigan Center for Translational Pathology, University of Michigan, Ann Arbor, Michigan
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12
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Pelkonen L, Sato K, Reinisalo M, Kidron H, Tachikawa M, Watanabe M, Uchida Y, Urtti A, Terasaki T. LC–MS/MS Based Quantitation of ABC and SLC Transporter Proteins in Plasma Membranes of Cultured Primary Human Retinal Pigment Epithelium Cells and Immortalized ARPE19 Cell Line. Mol Pharm 2017; 14:605-613. [DOI: 10.1021/acs.molpharmaceut.6b00782] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Affiliation(s)
- Laura Pelkonen
- School
of Pharmacy, Faculty of Health Sciences, University of Eastern Finland, 70210 Kuopio, Finland
| | - Kazuki Sato
- Division
of Membrane Transport and Drug Targeting, Graduate School of Pharmaceutical
Sciences, Tohoku University, Sendai, Japan
| | - Mika Reinisalo
- School
of Pharmacy, Faculty of Health Sciences, University of Eastern Finland, 70210 Kuopio, Finland
| | - Heidi Kidron
- Centre
for Drug Research, Division of Pharmaceutical Biosciences, Faculty
of Pharmacy, University of Helsinki, P.O. Box 56, FI-00014 Helsinki, Finland
| | - Masanori Tachikawa
- Division
of Membrane Transport and Drug Targeting, Graduate School of Pharmaceutical
Sciences, Tohoku University, Sendai, Japan
| | - Michitoshi Watanabe
- Division
of Membrane Transport and Drug Targeting, Graduate School of Pharmaceutical
Sciences, Tohoku University, Sendai, Japan
| | - Yasuo Uchida
- Division
of Membrane Transport and Drug Targeting, Graduate School of Pharmaceutical
Sciences, Tohoku University, Sendai, Japan
| | - Arto Urtti
- School
of Pharmacy, Faculty of Health Sciences, University of Eastern Finland, 70210 Kuopio, Finland
- Centre
for Drug Research, Division of Pharmaceutical Biosciences, Faculty
of Pharmacy, University of Helsinki, P.O. Box 56, FI-00014 Helsinki, Finland
| | - Tetsuya Terasaki
- Division
of Membrane Transport and Drug Targeting, Graduate School of Pharmaceutical
Sciences, Tohoku University, Sendai, Japan
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13
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Andersson M, Ersson L, Brandt I, Bergström U. Potential transfer of neurotoxic amino acid β-N-methylamino-alanine (BMAA) from mother to infant during breast-feeding: Predictions from human cell lines. Toxicol Appl Pharmacol 2017; 320:40-50. [PMID: 28174119 DOI: 10.1016/j.taap.2017.02.004] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2016] [Revised: 01/10/2017] [Accepted: 02/03/2017] [Indexed: 12/13/2022]
Abstract
β-N-methylamino-alanine (BMAA) is a non-protein amino acid produced by cyanobacteria, diatoms and dinoflagellates. BMAA has potential to biomagnify in a terrestrial food chain, and to bioaccumulate in fish and shellfish. We have reported that administration of [14C]l-BMAA to lactating mice and rats results in a mother to off-spring transfer via the milk. A preferential enantiomer-specific uptake of [14C]l-BMAA has also been demonstrated in differentiated murine mammary epithelium HC11 cells. These findings, together with neurotoxic effects of BMAA demonstrated both in vitro and in vivo, highlight the need to determine whether such transfer could also occur in humans. Here, we used four cell lines of human origin to examine and compare the transport of the two BMAA enantiomers in vitro. The uptake patterns of [14C]l- and [14C]d-BMAA in the human mammary MCF7 cell line were in agreement with the results in murine HC11 cells, suggesting a potential secretion of BMAA into human breast milk. The permeability coefficients for both [14C]l- and [14C]d-BMAA over monolayers of human intestinal Caco2 cells supported an efficient absorption from the human intestine. As a final step, transport experiments confirmed that [14C]l-and [14C]d-BMAA can be taken up by human SHSY5Y neuroblastoma cells and even more efficiently by human U343 glioblastoma cells. In competition experiments with various amino acids, the ASCT2 specific inhibitor benzylserine was the most effective inhibitor of [14C]l-BMAA uptake tested here. Altogether, our results suggest that BMAA can be transferred from an exposed mother, via the milk, to the brain of the nursed infant.
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Affiliation(s)
- Marie Andersson
- Department of Environmental Toxicology, Uppsala University, Norbyvägen 18A, SE-752 36 Uppsala, Sweden
| | - Lisa Ersson
- Department of Pharmaceutical Biosciences, Uppsala University, Box 591, SE-751 24 Uppsala, Sweden
| | - Ingvar Brandt
- Department of Environmental Toxicology, Uppsala University, Norbyvägen 18A, SE-752 36 Uppsala, Sweden.
| | - Ulrika Bergström
- Department of Environmental Toxicology, Uppsala University, Norbyvägen 18A, SE-752 36 Uppsala, Sweden; Swedish Defence Research Agency, Division of CBRN Defence and Security, SE-164 90 Stockholm, Sweden
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14
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Glia plasma membrane transporters: Key players in glutamatergic neurotransmission. Neurochem Int 2016; 98:46-55. [DOI: 10.1016/j.neuint.2016.04.004] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2015] [Revised: 03/07/2016] [Accepted: 04/06/2016] [Indexed: 12/27/2022]
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15
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Amacher DE. The regulation of human hepatic drug transporter expression by activation of xenobiotic-sensing nuclear receptors. Expert Opin Drug Metab Toxicol 2016; 12:1463-1477. [PMID: 27548410 DOI: 10.1080/17425255.2016.1223626] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
INTRODUCTION If a drug is found to be an inducer of hepatic drug metabolizing enzymes via activation of nuclear receptors such as pregnane X receptor (PXR) or constitutive androstane receptor (CAR), it is likely that drug transporters regulated through these same receptors will be induced as well. This review highlights what is currently known about the molecular mechanisms that regulate transporter expression and where the research is directed. Areas covered: This review is focused on publications that describe the role of activated hepatic nuclear receptors in the subsequent regulation of drug uptake and/or efflux transporters following exposure to xenobiotics. Expert opinion: Many of the published studies on the role of nuclear receptors in the regulation of drug transporters involve non-human test animals. But due to species response differences, these associations are not always applicable to humans. For this reason, some relevant human in vitro models have been developed, such as primary or cryopreserved human hepatocytes, human liver slices, or HepG2 or HuH7 cell lines transiently or stably transfected with PXR expression and reporter constructs as well as in vivo models such as PXR-humanized mice. These human-relevant test systems will continue to be developed and applied for the testing of investigational drugs.
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16
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Ma PK, Wei BH, Cao YL, Miao Q, Chen N, Guo CE, Chen HY, Zhang YJ. Pharmacokinetics, metabolism, and excretion of cycloastragenol, a potent telomerase activator in rats. Xenobiotica 2016; 47:526-537. [DOI: 10.1080/00498254.2016.1204568] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Affiliation(s)
- Peng-Kai Ma
- School of Chinese Materia Medica, Beijing University of Chinese Medicine, Beijing, China,
| | - Bao-Hong Wei
- School of Chinese Materia Medica, Beijing University of Chinese Medicine, Beijing, China,
- National Engineering Research Center for Marine Drugs, Ocean University of China, Qingdao, China, and
| | - Yan-Ling Cao
- Research Center for Life Science and Environmental Sciences, Haerbin University of Commerce, Haerbin, China
| | - Qing Miao
- School of Chinese Materia Medica, Beijing University of Chinese Medicine, Beijing, China,
| | - Ning Chen
- School of Chinese Materia Medica, Beijing University of Chinese Medicine, Beijing, China,
| | - Chang-E Guo
- School of Chinese Materia Medica, Beijing University of Chinese Medicine, Beijing, China,
| | - Hong-Ying Chen
- School of Chinese Materia Medica, Beijing University of Chinese Medicine, Beijing, China,
| | - Yu-Jie Zhang
- School of Chinese Materia Medica, Beijing University of Chinese Medicine, Beijing, China,
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17
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Blankenbach KV, Schwalm S, Pfeilschifter J, Meyer Zu Heringdorf D. Sphingosine-1-Phosphate Receptor-2 Antagonists: Therapeutic Potential and Potential Risks. Front Pharmacol 2016; 7:167. [PMID: 27445808 PMCID: PMC4914510 DOI: 10.3389/fphar.2016.00167] [Citation(s) in RCA: 44] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2016] [Accepted: 06/03/2016] [Indexed: 12/26/2022] Open
Abstract
The sphingosine-1-phosphate (S1P) signaling system with its specific G-protein-coupled S1P receptors, the enzymes of S1P metabolism and the S1P transporters, offers a multitude of promising targets for drug development. Until today, drug development in this area has nearly exclusively focused on (functional) antagonists at the S1P1 receptor, which cause a unique phenotype of immunomodulation. Accordingly, the first-in class S1P1 receptor modulator, fingolimod, has been approved for the treatment of relapsing-remitting multiple sclerosis, and novel S1P1 receptor (functional) antagonists are being developed for autoimmune and inflammatory diseases such as psoriasis, inflammatory bowel disease, lupus erythematodes, or polymyositis. Besides the S1P1 receptor, also S1P2 and S1P3 are widely expressed and regulate many diverse functions throughout the body. The S1P2 receptor, in particular, often exerts cellular functions which are opposed to the functions of the S1P1 receptor. As a consequence, antagonists at the S1P2 receptor have the potential to be useful in a contrasting context and different areas of indication compared to S1P1 antagonists. The present review will focus on the therapeutic potential of S1P2 receptor antagonists and discuss their opportunities as well as their potential risks. Open questions and areas which require further investigations will be emphasized in particular.
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Affiliation(s)
- Kira V Blankenbach
- Institut für Allgemeine Pharmakologie und Toxikologie, Klinikum der Johann Wolfgang Goethe-Universität Frankfurt am Main, Germany
| | - Stephanie Schwalm
- Institut für Allgemeine Pharmakologie und Toxikologie, Klinikum der Johann Wolfgang Goethe-Universität Frankfurt am Main, Germany
| | - Josef Pfeilschifter
- Institut für Allgemeine Pharmakologie und Toxikologie, Klinikum der Johann Wolfgang Goethe-Universität Frankfurt am Main, Germany
| | - Dagmar Meyer Zu Heringdorf
- Institut für Allgemeine Pharmakologie und Toxikologie, Klinikum der Johann Wolfgang Goethe-Universität Frankfurt am Main, Germany
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18
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Lilius TO, Jokinen V, Neuvonen MS, Niemi M, Kalso EA, Rauhala PV. Ketamine coadministration attenuates morphine tolerance and leads to increased brain concentrations of both drugs in the rat. Br J Pharmacol 2016; 172:2799-813. [PMID: 25297798 PMCID: PMC4439876 DOI: 10.1111/bph.12974] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2014] [Revised: 09/05/2014] [Accepted: 10/03/2014] [Indexed: 12/25/2022] Open
Abstract
Background and Purpose The effects of ketamine in attenuating morphine tolerance have been suggested to result from a pharmacodynamic interaction. We studied whether ketamine might increase brain morphine concentrations in acute coadministration, in morphine tolerance and morphine withdrawal. Experimental Approach Morphine minipumps (6 mg·day–1) induced tolerance during 5 days in Sprague–Dawley rats, after which s.c. ketamine (10 mg·kg–1) was administered. Tail flick, hot plate and rotarod tests were used for behavioural testing. Serum levels and whole tissue brain and liver concentrations of morphine, morphine-3-glucuronide, ketamine and norketamine were measured using HPLC-tandem mass spectrometry. Key Results In morphine-naïve rats, ketamine caused no antinociception whereas in morphine-tolerant rats there was significant antinociception (57% maximum possible effect in the tail flick test 90 min after administration) lasting up to 150 min. In the brain of morphine-tolerant ketamine-treated rats, the morphine, ketamine and norketamine concentrations were 2.1-, 1.4- and 3.4-fold, respectively, compared with the rats treated with morphine or ketamine only. In the liver of morphine-tolerant ketamine-treated rats, ketamine concentration was sixfold compared with morphine-naïve rats. After a 2 day morphine withdrawal period, smaller but parallel concentration changes were observed. In acute coadministration, ketamine increased the brain morphine concentration by 20%, but no increase in ketamine concentrations or increased antinociception was observed. Conclusions and Implications The ability of ketamine to induce antinociception in rats made tolerant to morphine may also be due to increased brain concentrations of morphine, ketamine and norketamine. The relevance of these findings needs to be assessed in humans.
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Affiliation(s)
- T O Lilius
- Institute of Biomedicine, Pharmacology, University of Helsinki, Finland
| | - V Jokinen
- Institute of Biomedicine, Pharmacology, University of Helsinki, Finland
| | - M S Neuvonen
- Haartman Institute, Department of Clinical Pharmacology, University of Helsinki, Finland
| | - M Niemi
- Haartman Institute, Department of Clinical Pharmacology, University of Helsinki, Finland.,HUSLAB, Helsinki University Central Hospital, Finland
| | - E A Kalso
- Institute of Biomedicine, Pharmacology, University of Helsinki, Finland.,Department of Anaesthesia, Intensive Care Medicine, Emergency Medicine and Pain Medicine, Pain Clinic, Helsinki University Central Hospital, Finland
| | - P V Rauhala
- Institute of Biomedicine, Pharmacology, University of Helsinki, Finland
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19
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Chapy H, Saubaméa B, Tournier N, Bourasset F, Behar-Cohen F, Declèves X, Scherrmann JM, Cisternino S. Blood-brain and retinal barriers show dissimilar ABC transporter impacts and concealed effect of P-glycoprotein on a novel verapamil influx carrier. Br J Pharmacol 2016; 173:497-510. [PMID: 26507673 DOI: 10.1111/bph.13376] [Citation(s) in RCA: 44] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2015] [Revised: 09/30/2015] [Accepted: 10/05/2015] [Indexed: 12/11/2022] Open
Abstract
BACKGROUND AND PURPOSE The respective impact and interplay between ABC (P-glycoprotein/P-gp/Abcb1a, BCRP/ABCG2, MRP/ABCC) and SLC transporter functions at the blood-brain barrier (BBB) and blood-retinal barriers (BRB) are incompletely understood. EXPERIMENTAL APPROACH We measured the initial cerebral and retinal distribution of selected ABC substrates by in situ carotid perfusion using P-gp/Bcrp knockout mice and chemical ABC/SLC modulation strategies. P-gp, Bcrp, Mrp1 and Mrp4 were studied by confocal retina imaging. KEY RESULTS Chemical or physical disruption of P-gp increased [(3) H]-verapamil transport by ~10-fold at the BBB and ~1.5-fold at the BRB. [(3) H]-Verapamil transport involved influx-mediated by an organic cation clonidine-sensitive/diphenhydramine-sensitive proton antiporter at both barriers; this effect was unmasked when P-gp was partially or fully inhibited/disrupted at the BBB. Studies of [(3) H]-mitoxantrone and [(3) H]-zidovudine transport suggested, respectively, that Bcrp efflux was less involved at the BRB than BBB, whereas Mrps were significantly and similarly involved at both barriers. Confocal imaging showed that P-gp and Bcrp were expressed in intra-retinal vessels (inner BRB/iBRB) but absent from the blood/basal membrane of cells of the retinal pigment epithelium (outer BRB/oBRB/RPE) where, in contrast, Mrp1 and Mrp4 were localized. CONCLUSIONS AND IMPLICATIONS P-gp, Bcrp, Mrp1 and Mrp4 are differentially expressed at the outer and inner BRB, resulting in an altered ability to limit substrate distribution at the retina as compared with the BBB. [(3) H]-Verapamil distribution is not P-gp-specific and involves a proton antiporter at both the BBB and BRB. However, this transport is concealed by P-gp at the BBB, but not at the BRB, where P-gp activity is reduced.
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Affiliation(s)
- Hélène Chapy
- Variabilité de Réponse aux Psychotropes, INSERM, U1144, Paris, France.,Faculté de Pharmacie, Université Paris Descartes, UMR-S 1144, Paris, France.,Université Paris Diderot, UMR-S 1144, Paris, France
| | - Bruno Saubaméa
- Variabilité de Réponse aux Psychotropes, INSERM, U1144, Paris, France.,Faculté de Pharmacie, Université Paris Descartes, UMR-S 1144, Paris, France.,Université Paris Diderot, UMR-S 1144, Paris, France
| | - Nicolas Tournier
- INSERM, CEA, Université Paris Sud, UMR 1023 - ERL 9218 CNRS, IMIV, Orsay, France
| | - Fanchon Bourasset
- Variabilité de Réponse aux Psychotropes, INSERM, U1144, Paris, France.,Faculté de Pharmacie, Université Paris Descartes, UMR-S 1144, Paris, France.,Université Paris Diderot, UMR-S 1144, Paris, France
| | - Francine Behar-Cohen
- Université Paris Descartes, UMR-S 1138, Paris, France.,Physiopathologies des Maladies Oculaires, INSERM U1138, Paris, France
| | - Xavier Declèves
- Variabilité de Réponse aux Psychotropes, INSERM, U1144, Paris, France.,Faculté de Pharmacie, Université Paris Descartes, UMR-S 1144, Paris, France.,Université Paris Diderot, UMR-S 1144, Paris, France.,Assistance Publique des Hôpitaux de Paris - AP-HP, Paris, France
| | - Jean-Michel Scherrmann
- Variabilité de Réponse aux Psychotropes, INSERM, U1144, Paris, France.,Faculté de Pharmacie, Université Paris Descartes, UMR-S 1144, Paris, France.,Université Paris Diderot, UMR-S 1144, Paris, France.,Assistance Publique des Hôpitaux de Paris - AP-HP, Paris, France
| | - Salvatore Cisternino
- Variabilité de Réponse aux Psychotropes, INSERM, U1144, Paris, France.,Faculté de Pharmacie, Université Paris Descartes, UMR-S 1144, Paris, France.,Université Paris Diderot, UMR-S 1144, Paris, France.,Assistance Publique des Hôpitaux de Paris - AP-HP, Paris, France
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20
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Walford T, Musa FI, Harper AGS. Nicergoline inhibits human platelet Ca(2+) signalling through triggering a microtubule-dependent reorganization of the platelet ultrastructure. Br J Pharmacol 2016; 173:234-47. [PMID: 26450366 PMCID: PMC4813371 DOI: 10.1111/bph.13361] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2015] [Revised: 08/27/2015] [Accepted: 09/23/2015] [Indexed: 12/26/2022] Open
Abstract
BACKGROUND AND PURPOSE Recently, we demonstrated that a pericellular Ca(2+) recycling system potentiates agonist-evoked Ca(2+) signalling and granule secretion in human platelets and hypothesized a role for the membrane complex (MC) in orchestrating the accumulation of Ca(2+) in the pericellular region. Previous work has demonstrated that treatment with high concentrations of nicergoline may disrupt the MC through an ability to trigger a re-organization of the dense tubular system. Experiments were therefore performed to assess whether nicergoline-induced changes in platelet ultrastructure affects thrombin-evoked Ca(2+) fluxes and dense granule secretion. EXPERIMENTAL APPROACH Thrombin-evoked Ca(2+) fluxes were monitored in Fura-2- or Fluo-5N-loaded human platelets, or using platelet suspensions containing Fluo-4 or Rhod-5N K(+) salts. Fluorescence microscopy was utilized to monitor microtubule structure and intracellular Ca(2+) store distribution in TubulinTracker- and Fluo-5N-loaded platelets respectively. Dense granule secretion was monitored using luciferin-luciferase. KEY RESULTS Nicergoline treatment inhibited thrombin-evoked Ca(2+) signalling and induced alterations in the microtubule structure and the distribution of intracellular Ca(2+) stores in platelets. Nicergoline altered the generation and spreading of thrombin-induced pericellular Ca(2+) signals and almost completely prevented dense granule secretion. Stabilization of microtubules using taxol reversed most effects of nicergoline on platelet Ca(2+) signalling and partially reversed its effects on dense granule secretion. CONCLUSIONS AND IMPLICATIONS Nicergoline-induced alterations to platelet ultrastructure disrupt platelet Ca(2+) signalling in a manner that would be predicted if the MC had been disrupted. These data suggest that nicergoline may be a useful prototype for the discovery of novel MC-disrupting anti-thrombotics.
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Affiliation(s)
- T Walford
- Institute for Science and Technology in Medicine, Keele University, Guy Hilton Research Centre, Stoke-on-Trent, Staffordshire, UK
| | - F I Musa
- Institute for Science and Technology in Medicine, Keele University, Guy Hilton Research Centre, Stoke-on-Trent, Staffordshire, UK
| | - A G S Harper
- Institute for Science and Technology in Medicine, Keele University, Guy Hilton Research Centre, Stoke-on-Trent, Staffordshire, UK
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21
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Cross AJ, Widzowski D, Maciag C, Zacco A, Hudzik T, Liu J, Nyberg S, Wood MW. Quetiapine and its metabolite norquetiapine: translation from in vitro pharmacology to in vivo efficacy in rodent models. Br J Pharmacol 2015; 173:155-66. [PMID: 26436896 DOI: 10.1111/bph.13346] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2014] [Revised: 09/03/2015] [Accepted: 09/24/2015] [Indexed: 01/01/2023] Open
Abstract
BACKGROUND AND PURPOSE Quetiapine has a range of clinical activity distinct from other atypical antipsychotic drugs, demonstrating efficacy as monotherapy in bipolar depression, major depressive disorder and generalized anxiety disorder. The neuropharmacological mechanisms underlying this clinical profile are not completely understood; however, the major active metabolite, norquetiapine, has been shown to have a distinct in vitro pharmacological profile consistent with a broad therapeutic range and may contribute to the clinical profile of quetiapine. EXPERIMENTAL APPROACH We evaluated quetiapine and norquetiapine, using in vitro binding and functional assays of targets known to be associated with antidepressant and anxiolytic drug actions and compared these activities with a representative range of established antipsychotics and antidepressants. To determine how the in vitro pharmacological properties translate into in vivo activity, we used preclinical animal models with translational relevance to established antidepressant-like and anxiolytic-like drug action. KEY RESULTS Norquetiapine had equivalent activity to established antidepressants at the noradrenaline transporter (NET), while quetiapine was inactive. Norquetiapine was active in the mouse forced swimming and rat learned helplessness tests. In in vivo receptor occupancy studies, norquetiapine had significant occupancy at NET at behaviourally relevant doses. Both quetiapine and norquetiapine were agonists at 5-HT1A receptors, and the anxiolytic-like activity of norquetiapine in rat punished responding was blocked by the 5-HT1A antagonist, WAY100635. CONCLUSIONS AND IMPLICATIONS Quetiapine and norquetiapine have multiple in vitro pharmacological actions, and results from preclinical studies suggest that activity at NET and 5-HT1A receptors contributes to the antidepressant and anxiolytic effects in patients treated with quetiapine.
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Affiliation(s)
- A J Cross
- AstraZeneca Neuroscience Innovative Medicines, Cambridge, MA, USA
| | - D Widzowski
- AstraZeneca Neuroscience Innovative Medicines, Cambridge, MA, USA
| | - C Maciag
- AstraZeneca Neuroscience Innovative Medicines, Cambridge, MA, USA
| | - A Zacco
- AstraZeneca Neuroscience Innovative Medicines, Cambridge, MA, USA
| | - T Hudzik
- AstraZeneca Neuroscience Innovative Medicines, Cambridge, MA, USA
| | - J Liu
- AstraZeneca R&D, Shanghai, China
| | - S Nyberg
- AstraZeneca R&D, Södertälje, Sweden
| | - M W Wood
- AstraZeneca Neuroscience Innovative Medicines, Cambridge, MA, USA
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22
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Weinreb O, Amit T, Bar-Am O, Youdim MBH. Neuroprotective effects of multifaceted hybrid agents targeting MAO, cholinesterase, iron and β-amyloid in ageing and Alzheimer's disease. Br J Pharmacol 2015; 173:2080-94. [PMID: 26332830 DOI: 10.1111/bph.13318] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2015] [Revised: 08/04/2015] [Accepted: 08/20/2015] [Indexed: 12/15/2022] Open
Abstract
UNLABELLED Alzheimer's disease (AD) is accepted nowadays as a complex neurodegenerative disorder with multifaceted cerebral pathologies, including extracellular deposition of amyloid β peptide-containing plaques, intracellular neurofibrillary tangles, progressive loss of cholinergic neurons, metal dyshomeostasis, mitochondrial dysfunction, neuroinflammation, glutamate excitoxicity, oxidative stress and increased MAO enzyme activity. This may explain why it is currently widely accepted that a more effective therapy for AD would result from the use of multifunctional drugs, which may affect more than one brain target involved in the disease pathology. The current review will discuss the potential benefits of novel multimodal neuroprotective, brain permeable drugs, recently developed by Youdim and collaborators, as a valuable therapeutic approach for AD treatment. The pharmacological and neuroprotective properties of these multitarget-directed ligands, which target MAO enzymes, the cholinergic system, iron accumulation and amyloid β peptide generation/aggregation are described, with a special emphasis on their potential therapeutic value for ageing and AD-associated cognitive functions. This review is conceived as a tribute to the broad neuropharmacology work of Professor Moussa Youdim, Professor Emeritus in the Faculty of Medicine and Director of Eve Topf Center of Excellence in Technion-Israel Institute of Technology, and Chief Scientific Officer of ABITAL Pharma Pipeline Ltd., at the occasion of his 75th birthday. LINKED ARTICLES This article is part of a themed section on Updating Neuropathology and Neuropharmacology of Monoaminergic Systems. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v173.13/issuetoc.
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Affiliation(s)
- Orly Weinreb
- Eve Topf Centers of Excellence for Neurodegenerative Diseases Research, Faculty of Medicine, Technion-Israel Institute of Technology, Haifa, Israel.,ABITAL Pharma Pipeline Ltd., Yokneam, Israel
| | - Tamar Amit
- Eve Topf Centers of Excellence for Neurodegenerative Diseases Research, Faculty of Medicine, Technion-Israel Institute of Technology, Haifa, Israel.,ABITAL Pharma Pipeline Ltd., Yokneam, Israel
| | - Orit Bar-Am
- Eve Topf Centers of Excellence for Neurodegenerative Diseases Research, Faculty of Medicine, Technion-Israel Institute of Technology, Haifa, Israel.,ABITAL Pharma Pipeline Ltd., Yokneam, Israel
| | - Moussa B H Youdim
- Eve Topf Centers of Excellence for Neurodegenerative Diseases Research, Faculty of Medicine, Technion-Israel Institute of Technology, Haifa, Israel.,ABITAL Pharma Pipeline Ltd., Yokneam, Israel
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23
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Xie Y, Hu Y, Smith DE. The proton-coupled oligopeptide transporter 1 plays a major role in the intestinal permeability and absorption of 5-aminolevulinic acid. Br J Pharmacol 2015; 173:167-76. [PMID: 26444978 DOI: 10.1111/bph.13356] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2015] [Revised: 09/22/2015] [Accepted: 09/30/2015] [Indexed: 12/28/2022] Open
Abstract
BACKGROUND AND PURPOSE 5-Aminolevulinic acid (5-ALA) has been widely used in photodynamic therapy and immunofluorescence of tumours. In the present study, the intestinal permeability and oral pharmacokinetics of 5-ALA were evaluated to probe the contribution of the proton-coupled oligopeptide transporter 1 (PEPT1) to the oral absorption and systemic exposure of this substrate. EXPERIMENTAL APPROACH In situ single-pass intestinal perfusions and in vivo oral pharmacokinetic studies were performed in wildtype and Pept1 knockout mice. Perfusion studies were performed as a function of concentration dependence, specificity and permeability of 5-ALA in different intestinal segments. Pharmacokinetic studies were performed after 0.2 and 2.0 μmoL·g(-1) doses of 5-ALA. KEY RESULTS The permeability of 5-ALA was substantial in duodenal, jejunal and ileal regions of wildtype mice, but the residual permeability of 5-ALA in the small intestine from Pept1 knockout mice was only about 10% of that in wildtype animals. The permeability of 5-ALA in jejunum was specific for PEPT1 with no apparent contribution of other transporters, including the proton-coupled amino acid transporter 1 (PAT1). After oral dosing, the systemic exposure of 5-ALA was reduced by about twofold during PEPT1 ablation, and the pharmacokinetics were dose-proportional after the 0.2 and 2.0 µmol·g(-1) doses. PEPT1 had a minor effect on the disposition and peripheral tissue distribution of 5-ALA. CONCLUSION AND IMPLICATIONS Our findings suggested a major role of PEPT1 in the intestinal permeability and oral absorption of 5-ALA. In contrast, another proton-coupled transporter, PAT1, appeared to play a limited role, at best.
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Affiliation(s)
- Yehua Xie
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Michigan, Ann Arbor, MI 48109, USA
| | - Yongjun Hu
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Michigan, Ann Arbor, MI 48109, USA
| | - David E Smith
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Michigan, Ann Arbor, MI 48109, USA
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24
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Todd SM, Arnold JC. Neural correlates of interactions between cannabidiol and Δ(9) -tetrahydrocannabinol in mice: implications for medical cannabis. Br J Pharmacol 2015; 173:53-65. [PMID: 26377899 DOI: 10.1111/bph.13333] [Citation(s) in RCA: 63] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2015] [Revised: 09/01/2015] [Accepted: 09/06/2015] [Indexed: 12/24/2022] Open
Abstract
BACKGROUND AND PURPOSE It has been proposed that medicinal strains of cannabis and therapeutic preparations would be safer with a more balanced concentration ratio of Δ(9) -tetrahydrocannabinol (THC) to cannabidiol (CBD), as CBD reduces the adverse psychotropic effects of THC. However, our understanding of CBD and THC interactions is limited and the brain circuitry mediating interactions between CBD and THC are unknown. The aim of this study was to investigate whether CBD modulated the functional effects and c-Fos expression induced by THC, using a 1:1 dose ratio that approximates therapeutic strains of cannabis and nabiximols. EXPERIMENTAL APPROACH Male C57BL/6 mice were treated with vehicle, CBD, THC or a combination of CBD and THC (10 mg·kg(-1) i.p. for both cannabinoids) to examine effects on locomotor activity, anxiety-related behaviour, body temperature and brain c-Fos expression (a marker of neuronal activation). KEY RESULTS CBD potentiated THC-induced locomotor suppression but reduced the hypothermic and anxiogenic effects of THC. CBD alone had no effect on these measures. THC increased brain activation as measured by c-Fos expression in 11 of the 35 brain regions studied. CBD co-administration suppressed THC-induced c-Fos expression in six of these brain regions. This effect was most pronounced in the medial preoptic nucleus and lateral periaqueductal gray. Treatment with CBD alone diminished c-Fos expression only in the central nucleus of the amygdala compared with vehicle. CONCLUSIONS AND IMPLICATIONS These data confirm that CBD modulated the pharmacological actions of THC and provide new information regarding brain regions involved in the interaction between CBD and THC.
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Affiliation(s)
- S M Todd
- Brain and Mind Centre, University of Sydney, Sydney, Australia.,Discipline of Pharmacology, School of Medical Science, University of Sydney, Sydney, Australia
| | - J C Arnold
- Brain and Mind Centre, University of Sydney, Sydney, Australia.,Discipline of Pharmacology, School of Medical Science, University of Sydney, Sydney, Australia
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25
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Heger J, Schulz R, Euler G. Molecular switches under TGFβ signalling during progression from cardiac hypertrophy to heart failure. Br J Pharmacol 2015; 173:3-14. [PMID: 26431212 DOI: 10.1111/bph.13344] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2015] [Revised: 07/23/2015] [Accepted: 09/29/2015] [Indexed: 12/14/2022] Open
Abstract
Cardiac hypertrophy is a mechanism to compensate for increased cardiac work load, that is, after myocardial infarction or upon pressure overload. However, in the long run cardiac hypertrophy is a prevailing risk factor for the development of heart failure. During pathological remodelling processes leading to heart failure, decompensated hypertrophy, death of cardiomyocytes by apoptosis or necroptosis and fibrosis as well as a progressive dysfunction of cardiomyocytes are apparent. Interestingly, the induction of hypertrophy, cell death or fibrosis is mediated by similar signalling pathways. Therefore, tiny changes in the signalling cascade are able to switch physiological cardiac remodelling to the development of heart failure. In the present review, we will describe examples of these molecular switches that change compensated hypertrophy to the development of heart failure and will focus on the importance of the signalling cascades of the TGFβ superfamily in this process. In this context, potential therapeutic targets for pharmacological interventions that could attenuate the progression of heart failure will be discussed.
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Affiliation(s)
- J Heger
- Institute of Physiology, Justus Liebig University, Giessen, Germany
| | - R Schulz
- Institute of Physiology, Justus Liebig University, Giessen, Germany
| | - G Euler
- Institute of Physiology, Justus Liebig University, Giessen, Germany
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26
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Pu S, Ren L, Liu Q, Kuang J, Shen J, Cheng S, Zhang Y, Jiang W, Zhang Z, Jiang C, He J. Loss of 5-lipoxygenase activity protects mice against paracetamol-induced liver toxicity. Br J Pharmacol 2015; 173:66-76. [PMID: 26398229 DOI: 10.1111/bph.13336] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2015] [Revised: 08/12/2015] [Accepted: 09/17/2015] [Indexed: 02/06/2023] Open
Abstract
BACKGROUND AND PURPOSE Paracetamol (acetaminophen) is the most widely used over-the-counter analgesic and overdosing with paracetamol is the leading cause of hospital admission for acute liver failure. 5-Lipoxygenase (5-LO) catalyses arachidonic acid to form LTs, which lead to inflammation and oxidative stress. In this study, we examined whether deletion or pharmacological inhibition of 5-LO could protect mice against paracetamol-induced hepatic toxicity. EXPERIMENTAL APPROACH Both genetic deletion and pharmacological inhibition of 5-LO in C57BL/6J mice were used to study the role of this enzyme in paracetamol induced liver toxicity. Serum and tissue biochemistry, H&E staining, and real-time PCR were used to assess liver toxicity. KEY RESULTS Deletion or pharmacological inhibition of 5-LO in mice markedly ameliorated paracetamol-induced hepatic injury, as shown by decreased serum alanine transaminase and aspartate aminotransferase levels and hepatic centrilobular necrosis. The hepatoprotective effect of 5-LO inhibition was associated with induction of the antitoxic phase II conjugating enzyme, sulfotransferase2a1, suppression of the pro-toxic phase I CYP3A11 and reduction of the hepatic transporter MRP3. In 5-LO(-/-) mice, levels of GSH were increased, and oxidative stress decreased. In addition, PPAR α, a nuclear receptor that confers resistance to paracetamol toxicity, was activated in 5-LO(-/-) mice. CONCLUSIONS AND IMPLICATIONS The activity of 5-LO may play a critical role in paracetamol-induced hepatic toxicity by regulating paracetamol metabolism and oxidative stress.
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Affiliation(s)
- Shiyun Pu
- Department of Pharmacy, Collaborative Innovation Center of Biotherapy, West China Hospital of Sichuan University, Chengdu, China
| | - Lin Ren
- Department of Pharmacy, Collaborative Innovation Center of Biotherapy, West China Hospital of Sichuan University, Chengdu, China
| | - Qinhui Liu
- Laboratory of Clinical Pharmacy and Adverse Drug Reaction, Collaborative Innovation Center of Biotherapy, West China Hospital of Sichuan University, Chengdu, China
| | - Jiangying Kuang
- Department of Pharmacy, Collaborative Innovation Center of Biotherapy, West China Hospital of Sichuan University, Chengdu, China
| | - Jing Shen
- Department of Pharmacy, Collaborative Innovation Center of Biotherapy, West China Hospital of Sichuan University, Chengdu, China
| | - Shihai Cheng
- Department of Pharmacy, Collaborative Innovation Center of Biotherapy, West China Hospital of Sichuan University, Chengdu, China
| | - Yuwei Zhang
- Division of Endocrinology and Metabolism, Collaborative Innovation Center of Biotherapy, West China Hospital of Sichuan University, Chengdu, China
| | - Wei Jiang
- Molecular Medicine Research Center, State Key Laboratory of Biotherapy and Cancer Center, Collaborative Innovation Center of Biotherapy, West China Hospital of Sichuan University, Chengdu, China
| | - Zhiyong Zhang
- Department of Pharmacy, Collaborative Innovation Center of Biotherapy, West China Hospital of Sichuan University, Chengdu, China
| | - Changtao Jiang
- Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Peking University, Beijing, China
| | - Jinhan He
- Department of Pharmacy, Collaborative Innovation Center of Biotherapy, West China Hospital of Sichuan University, Chengdu, China.,Laboratory of Clinical Pharmacy and Adverse Drug Reaction, Collaborative Innovation Center of Biotherapy, West China Hospital of Sichuan University, Chengdu, China
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27
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Schmid D, Koenig X, Bulusu S, Schicker K, Freissmuth M, Sitte HH, Sandtner W. The conservative view: is it necessary to implant a stent into the dopamine transporter? Br J Pharmacol 2015; 172:4775-8. [PMID: 24824446 PMCID: PMC4561504 DOI: 10.1111/bph.12766] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2014] [Revised: 04/01/2014] [Accepted: 04/15/2014] [Indexed: 11/30/2022] Open
Abstract
This article is a reply to De Felice LJ and Cameron KN (2015). Comments on ‘A quantitative model of amphetamine action on the serotonin transporter’, by Sandtner et al., Br J Pharmacol 171: 1007–1018. Br J Pharmacol 172: this issue, doi: 10.1111/bph.12767, commenting on Sandtner W, Schmid D, Schicker K, Gerstbrein K, Koenig X, Mayer FP, Boehm S, Freissmuth M and Sitte HH (2014). A quantitative model of amphetamine action on the 5-HT transporter. Br J Pharmacol 171: 1007–1018. doi: 10.1111/bph.12520
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Affiliation(s)
- D Schmid
- Center of Physiology and Pharmacology, Medical University Vienna, Vienna, Austria
| | - X Koenig
- Center of Physiology and Pharmacology, Medical University Vienna, Vienna, Austria
| | - S Bulusu
- Center of Physiology and Pharmacology, Medical University Vienna, Vienna, Austria
| | - K Schicker
- Center of Physiology and Pharmacology, Medical University Vienna, Vienna, Austria
| | - M Freissmuth
- Center of Physiology and Pharmacology, Medical University Vienna, Vienna, Austria
| | - H H Sitte
- Center of Physiology and Pharmacology, Medical University Vienna, Vienna, Austria
| | - W Sandtner
- Center of Physiology and Pharmacology, Medical University Vienna, Vienna, Austria
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28
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De Felice LJ, Cameron KN. Comments on 'A quantitative model of amphetamine action on the serotonin transporter', by Sandtner et al., Br J Pharmacol 171: 1007-1018. Br J Pharmacol 2015; 172:4772-4. [PMID: 24824549 DOI: 10.1111/bph.12767] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2014] [Accepted: 02/26/2014] [Indexed: 01/03/2023] Open
Affiliation(s)
- Louis J De Felice
- Department Physiology and Biophysics, Virginia Commonwealth University, Richmond, VA, USA
| | - Krasnodara N Cameron
- Department Physiology and Biophysics, Virginia Commonwealth University, Richmond, VA, USA
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29
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McPartland JM, Duncan M, Di Marzo V, Pertwee RG. Are cannabidiol and Δ(9) -tetrahydrocannabivarin negative modulators of the endocannabinoid system? A systematic review. Br J Pharmacol 2015; 172:737-53. [PMID: 25257544 DOI: 10.1111/bph.12944] [Citation(s) in RCA: 352] [Impact Index Per Article: 39.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2014] [Revised: 09/12/2014] [Accepted: 09/16/2014] [Indexed: 12/12/2022] Open
Abstract
Based upon evidence that the therapeutic properties of Cannabis preparations are not solely dependent upon the presence of Δ(9) -tetrahydrocannabinol (THC), pharmacological studies have been recently carried out with other plant cannabinoids (phytocannabinoids), particularly cannabidiol (CBD) and Δ(9) -tetrahydrocannabivarin (THCV). Results from some of these studies have fostered the view that CBD and THCV modulate the effects of THC via direct blockade of cannabinoid CB1 receptors, thus behaving like first-generation CB1 receptor inverse agonists, such as rimonabant. Here, we review in vitro and ex vivo mechanistic studies of CBD and THCV, and synthesize data from these studies in a meta-analysis. Synthesized data regarding mechanisms are then used to interpret results from recent pre-clinical animal studies and clinical trials. The evidence indicates that CBD and THCV are not rimonabant-like in their action and thus appear very unlikely to produce unwanted CNS effects. They exhibit markedly disparate pharmacological profiles particularly at CB1 receptors: CBD is a very low-affinity CB1 ligand that can nevertheless affect CB1 receptor activity in vivo in an indirect manner, while THCV is a high-affinity CB1 receptor ligand and potent antagonist in vitro and yet only occasionally produces effects in vivo resulting from CB1 receptor antagonism. THCV has also high affinity for CB2 receptors and signals as a partial agonist, differing from both CBD and rimonabant. These cannabinoids illustrate how in vitro mechanistic studies do not always predict in vivo pharmacology and underlie the necessity of testing compounds in vivo before drawing any conclusion on their functional activity at a given target.
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Affiliation(s)
- John M McPartland
- Division of Molecular Biology, GW Pharmaceuticals, Salisbury, Wiltshire, UK
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30
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Barr JL, Rasmussen BA, Tallarida CS, Scholl JL, Forster GL, Unterwald EM, Rawls SM. Ceftriaxone attenuates acute cocaine-evoked dopaminergic neurotransmission in the nucleus accumbens of the rat. Br J Pharmacol 2015; 172:5414-24. [PMID: 26375494 PMCID: PMC4950793 DOI: 10.1111/bph.13330] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2015] [Revised: 08/17/2015] [Accepted: 08/19/2015] [Indexed: 12/24/2022] Open
Abstract
BACKGROUND AND PURPOSE Ceftriaxone is a β-lactam antibiotic and glutamate transporter activator that reduces the reinforcing effects of psychostimulants. Ceftriaxone also reduces locomotor activation following acute psychostimulant exposure, suggesting that alterations in dopamine transmission in the nucleus accumbens contribute to its mechanism of action. In the present studies we tested the hypothesis that pretreatment with ceftriaxone disrupts acute cocaine-evoked dopaminergic neurotransmission in the nucleus accumbens. EXPERIMENTAL APPROACH Adult male Sprague-Dawley rats were pretreated with saline or ceftriaxone (200 mg kg(-1) , i.p. × 10 days) and then challenged with cocaine (15 mg kg(-1) , i.p.). Motor activity, dopamine efflux (via in vivo microdialysis) and protein levels of tyrosine hydroxylase (TH), the dopamine transporter and organic cation transporter as well as α-synuclein, Akt and GSK3β were analysed in the nucleus accumbens. KEY RESULTS Ceftriaxone-pretreated rats challenged with cocaine displayed reduced locomotor activity and accumbal dopamine efflux compared with saline-pretreated controls challenged with cocaine. The reduction in cocaine-evoked dopamine levels was not counteracted by excitatory amino acid transporter 2 blockade in the nucleus accumbens. Pretreatment with ceftriaxone increased Akt/GSK3β signalling in the nucleus accumbens and reduced levels of dopamine transporter, TH and phosphorylated α-synuclein, indicating that ceftriaxone affects numerous proteins involved in dopaminergic transmission. CONCLUSIONS AND IMPLICATIONS These results are the first evidence that ceftriaxone affects cocaine-evoked dopaminergic transmission, in addition to its well-described effects on glutamate, and suggest that its ability to attenuate cocaine-induced behaviours, such as psychomotor activity, is due in part to reduced dopaminergic neurotransmission in the nucleus accumbens.
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Affiliation(s)
- J L Barr
- Department of Pharmacology and Centre for Substance Abuse ResearchTemple University School of MedicinePhiladelphiaPAUSA
| | - B A Rasmussen
- Department of Pharmacology and Centre for Substance Abuse ResearchTemple University School of MedicinePhiladelphiaPAUSA
| | - C S Tallarida
- Department of Pharmacology and Centre for Substance Abuse ResearchTemple University School of MedicinePhiladelphiaPAUSA
| | - J L Scholl
- Centre for Brain and Behaviour Research, Division of Basic Biomedical SciencesSanford School of Medicine at the University of South DakotaVermillionSDUSA
| | - G L Forster
- Centre for Brain and Behaviour Research, Division of Basic Biomedical SciencesSanford School of Medicine at the University of South DakotaVermillionSDUSA
| | - E M Unterwald
- Department of Pharmacology and Centre for Substance Abuse ResearchTemple University School of MedicinePhiladelphiaPAUSA
| | - S M Rawls
- Department of Pharmacology and Centre for Substance Abuse ResearchTemple University School of MedicinePhiladelphiaPAUSA
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31
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Lee MKS, Moore XL, Fu Y, Al-Sharea A, Dragoljevic D, Fernandez-Rojo MA, Parton R, Sviridov D, Murphy AJ, Chin-Dusting JPF. High-density lipoprotein inhibits human M1 macrophage polarization through redistribution of caveolin-1. Br J Pharmacol 2015; 173:741-51. [PMID: 26332942 DOI: 10.1111/bph.13319] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2014] [Revised: 08/19/2015] [Accepted: 08/25/2015] [Indexed: 12/11/2022] Open
Abstract
BACKGROUND AND PURPOSE Monocyte-derived macrophages are critical in the development of atherosclerosis and can adopt a wide range of functional phenotypes depending on their surrounding milieu. High-density lipoproteins (HDLs) have many cardio-protective properties including potent anti-inflammatory effects. We investigated the effects of HDL on human macrophage phenotype and the mechanisms by which these occur. EXPERIMENTAL APPROACH Human blood monocytes were differentiated into macrophages in the presence or absence of HDL and were then induced to either an inflammatory macrophage (M1) or anti-inflammatory macrophage (M2) phenotype using LPS and IFN-γ or IL-4, respectively. KEY RESULTS HDL inhibited the induction of macrophages to an M1-phenotype, as evidenced by a decrease in the expression of M1-specific cell surface markers CD192 and CD64, as well as M1-associated inflammatory genes TNF-α, IL-6 and MCP-1 (CCL2). HDL also inhibited M1 function by reducing the production of ROS. In contrast, HDL had no effect on macrophage induction to the M2-phenotype. Similarly, methyl-β-cyclodextrin, a non-specific cholesterol acceptor also suppressed the induction of M1 suggesting that cholesterol efflux is important in this process. Furthermore, HDL decreased membrane caveolin-1 in M1 macrophages. We confirmed that caveolin-1 is required for HDL to inhibit M1 induction as bone marrow-derived macrophages from caveolin-1 knockout mice continued to polarize into M1-phenotype despite the presence of HDL. Moreover, HDL decreased ERK1/2 and STAT3 phosphorylation in M1 macrophages. CONCLUSIONS AND IMPLICATIONS We concluded that HDL reduces the induction of macrophages to the inflammatory M1-phenotype via redistribution of caveolin-1, preventing the activation of ERK1/2 and STAT3.
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Affiliation(s)
- Man K S Lee
- Baker IDI Heart and Diabetes Institute, Melbourne, Australia.,Department of Medicine (Alfred), Monash University, Melbourne, Australia
| | - Xiao-Lei Moore
- Baker IDI Heart and Diabetes Institute, Melbourne, Australia
| | - Yi Fu
- Baker IDI Heart and Diabetes Institute, Melbourne, Australia
| | - Annas Al-Sharea
- Baker IDI Heart and Diabetes Institute, Melbourne, Australia.,Department of Medicine (Alfred), Monash University, Melbourne, Australia
| | - Dragana Dragoljevic
- Baker IDI Heart and Diabetes Institute, Melbourne, Australia.,Department of Medicine (Alfred), Monash University, Melbourne, Australia
| | - Manuel A Fernandez-Rojo
- Department of Cell and Molecular Biology, QIMR Berghofer Medical Research Institute, Brisbane, Australia
| | - Robert Parton
- Institute for Molecular Bioscience and Centre for Microscopy and Microanalysis, The University of Queensland, Brisbane, Australia
| | - Dmitri Sviridov
- Baker IDI Heart and Diabetes Institute, Melbourne, Australia
| | - Andrew J Murphy
- Baker IDI Heart and Diabetes Institute, Melbourne, Australia.,Department of Immunology, Monash University, Melbourne, Australia
| | - Jaye P F Chin-Dusting
- Baker IDI Heart and Diabetes Institute, Melbourne, Australia.,Department of Medicine (Alfred), Monash University, Melbourne, Australia
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32
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Paci M, Hyttinen J, Rodriguez B, Severi S. Human induced pluripotent stem cell-derived versus adult cardiomyocytes: an in silico electrophysiological study on effects of ionic current block. Br J Pharmacol 2015; 172:5147-60. [PMID: 26276951 PMCID: PMC4629192 DOI: 10.1111/bph.13282] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2015] [Revised: 07/29/2015] [Accepted: 08/03/2015] [Indexed: 12/28/2022] Open
Abstract
Background and Purpose Two new technologies are likely to revolutionize cardiac safety and drug development: in vitro experiments on human‐induced pluripotent stem cell‐derived cardiomyocytes (hiPSC‐CMs) and in silico human adult ventricular cardiomyocyte (hAdultV‐CM) models. Their combination was recently proposed as a potential replacement for the present hERG‐based QT study for pharmacological safety assessments. Here, we systematically compared in silico the effects of selective ionic current block on hiPSC‐CM and hAdultV‐CM action potentials (APs), to identify similarities/differences and to illustrate the potential of computational models as supportive tools for evaluating new in vitro technologies. Experimental Approach In silico AP models of ventricular‐like and atrial‐like hiPSC‐CMs and hAdultV‐CM were used to simulate the main effects of four degrees of block of the main cardiac transmembrane currents. Key Results Qualitatively, hiPSC‐CM and hAdultV‐CM APs showed similar responses to current block, consistent with results from experiments. However, quantitatively, hiPSC‐CMs were more sensitive to block of (i) L‐type Ca2+ currents due to the overexpression of the Na+/Ca2+ exchanger (leading to shorter APs) and (ii) the inward rectifier K+ current due to reduced repolarization reserve (inducing diastolic potential depolarization and repolarization failure). Conclusions and Implications In silico hiPSC‐CMs and hAdultV‐CMs exhibit a similar response to selective current blocks. However, overall hiPSC‐CMs show greater sensitivity to block, which may facilitate in vitro identification of drug‐induced effects. Extrapolation of drug effects from hiPSC‐CM to hAdultV‐CM and pro‐arrhythmic risk assessment can be facilitated by in silico predictions using biophysically‐based computational models.
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Affiliation(s)
- M Paci
- Department of Electronics and Communications Engineering, Tampere University of Technology, BioMediTech, Tampere, Finland
| | - J Hyttinen
- Department of Electronics and Communications Engineering, Tampere University of Technology, BioMediTech, Tampere, Finland
| | - B Rodriguez
- Department of Computer Science, University of Oxford, Oxford, UK
| | - S Severi
- Department of Electrical, Electronic and Information Engineering 'Guglielmo Marconi', University of Bologna, Cesena (FC), Italy
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Chapy H, Goracci L, Vayer P, Parmentier Y, Carrupt PA, Declèves X, Scherrmann JM, Cisternino S, Cruciani G. Pharmacophore-based discovery of inhibitors of a novel drug/proton antiporter in human brain endothelial hCMEC/D3 cell line. Br J Pharmacol 2015. [PMID: 26220580 DOI: 10.1111/bph.13258] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
BACKGROUND AND PURPOSE An influx drug/proton antiporter of unknown structure has been functionally demonstrated at the blood-brain barrier. This transporter, which handles some psychoactive drugs like diphenhydramine, clonidine, oxycodone, nicotine and cocaine, could represent a new pharmacological target in drug addiction therapy. However, at present there are no known drugs/inhibitors that effectively inhibit/modulate this transporter in vivo. EXPERIMENTAL APPROACH The FLAPpharm approach was used to establish a pharmacophore model for inhibitors of this transporter. The inhibitory potency of 44 selected compounds was determined against the specific substrate, [(3)H]-clonidine, in the human cerebral endothelial cell line hCMEC/D3 and ranked as good, medium, weak or non-inhibitor. KEY RESULTS The pharmacophore model obtained was used as a template to screen xenobiotic and endogenous compounds from databases [Specs, Recon2, Human Metabolome Database (HMDB), human intestinal transporter database], and hypothetical candidates were tested in vitro to determine their inhibitory capacity with [(3)H]-clonidine. According to the transporter database, 80% of the proton antiporter inhibitor candidates could inhibit P-glycoprotein/MDR1/ABCB1 and specificity is improved by reducing inhibitor size/shape and increasing water solubility. Virtual screening results using HMDB and Recon2 for endogenous compounds appropriately scored tryptamine as an inhibitor. CONCLUSIONS AND IMPLICATIONS The pharmacophore model for the proton-antiporter inhibitors was a good predictor of known inhibitors and allowed us to identify new good inhibitors. This model marks a new step towards the discovery of this drug/proton antiporter and will be of great use for the discovery and design of potent inhibitors that could potentially help to assess and validate its pharmacological role in drug addiction in vivo.
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Affiliation(s)
- Hélène Chapy
- INSERM U1144, Variabilité de réponse aux psychotropes, Paris, 75006, France.,UMR-S 1144, Université Paris Descartes, Paris, 75006, France.,UMR-S 1144, Université Paris Diderot, Paris, 75013, France
| | - Laura Goracci
- Department of Chemistry, Biology and Biotechnology, University of Perugia, Perugia, 06123, Italy
| | - Philippe Vayer
- Département de recherche biopharmaceutique, Technologie Servier, Orléans, 45000, France
| | - Yannick Parmentier
- Département de recherche biopharmaceutique, Technologie Servier, Orléans, 45000, France
| | - Pierre-Alain Carrupt
- Laboratoire de Pharmacochimie, Université de Genève, Genève, CH-1211, Switzerland
| | - Xavier Declèves
- INSERM U1144, Variabilité de réponse aux psychotropes, Paris, 75006, France.,UMR-S 1144, Université Paris Descartes, Paris, 75006, France.,UMR-S 1144, Université Paris Diderot, Paris, 75013, France.,Assistance Publique des Hôpitaux de Paris (AP-HP), Paris, France
| | - Jean-Michel Scherrmann
- INSERM U1144, Variabilité de réponse aux psychotropes, Paris, 75006, France.,UMR-S 1144, Université Paris Descartes, Paris, 75006, France.,UMR-S 1144, Université Paris Diderot, Paris, 75013, France.,Assistance Publique des Hôpitaux de Paris (AP-HP), Paris, France
| | - Salvatore Cisternino
- INSERM U1144, Variabilité de réponse aux psychotropes, Paris, 75006, France.,UMR-S 1144, Université Paris Descartes, Paris, 75006, France.,UMR-S 1144, Université Paris Diderot, Paris, 75013, France.,Assistance Publique des Hôpitaux de Paris (AP-HP), Paris, France
| | - Gabriele Cruciani
- Department of Chemistry, Biology and Biotechnology, University of Perugia, Perugia, 06123, Italy
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Kolisnyk B, Al-Onaizi MA, Prado VF, Prado MAM. α7 nicotinic ACh receptor-deficient mice exhibit sustained attention impairments that are reversed by β2 nicotinic ACh receptor activation. Br J Pharmacol 2015. [PMID: 26222090 DOI: 10.1111/bph.13260] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
BACKGROUND AND PURPOSE Disruptions of executive function, including attentional deficits, are a hallmark of a number of diseases. ACh in the prefrontal cortex regulates attentive behaviour; however, the role of α7 nicotinic ACh receptor (α7nAChR) in attention is contentious. EXPERIMENTAL APPROACH In order to probe attention, we trained both wild-type and α7nAChR knockout mice on a touch screen-based five-choice serial reaction time task (5-CSRT). Following training procedures, we then tested sustained attention using a probe trial experiment. To further differentiate the role of specific nicotinic receptors in attention, we then tested the effects of both α7nAChR and β2nAChR agonists on the performance of both wild-type and knockout mice on the 5-CSRT task. KEY RESULTS At low doses, α7nAChR agonists improved attentional performance of wild-type mice, while high doses had deleterious effects on attention. α7nAChR knockout mice displayed deficits in sustained attention that were not ameliorated by α7nAChR agonists. However, these deficits were completely reversed by the administration of a β2nAChR agonist. Furthermore, administration of a β2nAChR agonist in α7nAChR knockout mice elicited similar biochemical response in the prefrontal cortex as the administration of α7nAChR agonists in wild-type mice. CONCLUSIONS AND IMPLICATIONS Our experiments reveal an intricate relationship between distinct nicotinic receptors to regulate attentional performance and provide the basis for targeting β2nAChRs pharmacologically to decrease attentional deficits due to a dysfunction in α7nAChRs.
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Affiliation(s)
- Benjamin Kolisnyk
- Robarts Research Institute, Schulich School of Medicine & Dentistry, University of Western Ontario, London, ON, Canada.,Graduate Program in Neuroscience, University of Western Ontario, London, ON, Canada
| | - Mohammed A Al-Onaizi
- Robarts Research Institute, Schulich School of Medicine & Dentistry, University of Western Ontario, London, ON, Canada.,Department of Anatomy and Cell Biology, University of Western Ontario, London, ON, Canada
| | - Vania F Prado
- Robarts Research Institute, Schulich School of Medicine & Dentistry, University of Western Ontario, London, ON, Canada.,Graduate Program in Neuroscience, University of Western Ontario, London, ON, Canada.,Department of Physiology and Pharmacology, University of Western Ontario, London, ON, Canada.,Department of Anatomy and Cell Biology, University of Western Ontario, London, ON, Canada
| | - Marco A M Prado
- Robarts Research Institute, Schulich School of Medicine & Dentistry, University of Western Ontario, London, ON, Canada.,Graduate Program in Neuroscience, University of Western Ontario, London, ON, Canada.,Department of Physiology and Pharmacology, University of Western Ontario, London, ON, Canada.,Department of Anatomy and Cell Biology, University of Western Ontario, London, ON, Canada
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Hsu CY, Sulake RS, Huang PK, Shih HY, Sie HW, Lai YK, Chen C, Weng CF. Synthetic (+)-antroquinonol exhibits dual actions against insulin resistance by triggering AMP kinase and inhibiting dipeptidyl peptidase IV activities. Br J Pharmacol 2015; 172:38-49. [PMID: 24977411 DOI: 10.1111/bph.12828] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2014] [Revised: 06/03/2014] [Accepted: 06/19/2014] [Indexed: 12/22/2022] Open
Abstract
BACKGROUND AND PURPOSE The fungal product (+)-antroquinonol activates AMP kinase (AMPK) activity in cancer cell lines. The present study was conducted to examine whether chemically synthesized (+)-antroquinonol exhibited beneficial metabolic effects in insulin-resistant states by activating AMPK and inhibiting dipeptidyl peptidase IV (DPP IV) activity. EXPERIMENTAL APPROACH Effects of (+)-antroquinonol on DPP IV activity were measured with a DPPIV Assay Kit and effects on GLP-1-induced PKA were measured in AR42J cells. Translocation of the glucose transporter 4, GLUT4, induced either by insulin-dependent PI3K/AKT signalling or by insulin-independent AMPK activation, was assayed in differentiated myotubes. Glucose uptake and GLUT4 translocation were assayed in L6 myocytes. Mice with diet-induced obesity were used to assess effects of acute and chronic treatment with (+)-antroquinonol on glycaemic control in vivo. KEY RESULTS The results showed that of (+)-antroquinonol (100 μM ) inhibited the DPP IV activity as effectively as the clinically used inhibitor, sitagliptin. The phosphorylation of AMPK Thr(172) in differentiated myotubes was significantly increased by (+)-antroquinonol. In cells simultaneously treated with S961 (insulin receptor antagonist), insulin and (+)-antroquinonol, the combination of (+)-antroquinonol plus insulin still increased both GLUT4 translocation and glucose uptake. Further, (+)-antroquinonol and sitagliptin reduced blood glucose, when given acutely or chronically to DIO mice. CONCLUSIONS AND IMPLICATIONS Chemically synthesized (+)-antroquinonol exhibits dual effects to ameliorate insulin resistance, by increasing AMPK activity and GLUT4 translocation, along with inhibiting DPP IV activity.
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Affiliation(s)
- C Y Hsu
- Institute of Biotechnology, National Dong-Hwa University, Hualien, Taiwan; Institute of Biotechnology, National Tsing Hua University, Hsinchu, Taiwan
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Abstract
The variety of physiological functions controlled by dopamine in the brain and periphery is mediated by the D1, D2, D3, D4 and D5 dopamine GPCRs. Drugs acting on dopamine receptors are significant tools for the management of several neuropsychiatric disorders including schizophrenia, bipolar disorder, depression and Parkinson's disease. Recent investigations of dopamine receptor signalling have shown that dopamine receptors, apart from their canonical action on cAMP-mediated signalling, can regulate a myriad of cellular responses to fine-tune the expression of dopamine-associated behaviours and functions. Such signalling mechanisms may involve alternate G protein coupling or non-G protein mechanisms involving ion channels, receptor tyrosine kinases or proteins such as β-arrestins that are classically involved in GPCR desensitization. Another level of complexity is the growing appreciation of the physiological roles played by dopamine receptor heteromers. Applications of new in vivo techniques have significantly furthered the understanding of the physiological functions played by dopamine receptors. Here we provide an update of the current knowledge regarding the complex biology, signalling, physiology and pharmacology of dopamine receptors.
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Lykke K, Töllner K, Römermann K, Feit PW, Erker T, MacAulay N, Löscher W. Structure-activity relationships of bumetanide derivatives: correlation between diuretic activity in dogs and inhibition of the human NKCC2A transporter. Br J Pharmacol 2015; 172:4469-4480. [PMID: 26101812 PMCID: PMC4562508 DOI: 10.1111/bph.13231] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2015] [Revised: 05/28/2015] [Accepted: 06/12/2015] [Indexed: 12/24/2022] Open
Abstract
BACKGROUND AND PURPOSE The N-K-Cl cotransporters (NKCCs) mediate the coupled, electroneutral movement of Na+ , K+ and Cl- ions across cell membranes. There are two isoforms of this cation co-transporter, NKCC1 and NKCC2. NKCC2 is expressed primarily in the kidney and is the target of diuretics such as bumetanide. Bumetanide was discovered by screening ∼5000 3-amino-5-sulfamoylbenzoic acid derivatives, long before NKCC2 was identified in the kidney. Therefore, structure-activity studies on effects of bumetanide derivatives on NKCC2 are not available. EXPERIMENTAL APPROACH In this study, the effect of a series of diuretically active bumetanide derivatives was investigated on human NKCC2 variant A (hNKCC2A) expressed in Xenopus laevis oocytes. KEY RESULTS Bumetanide blocked hNKCC2A transport with an IC50 of 4 μM. There was good correlation between the diuretic potency of bumetanide and its derivatives in dogs and their inhibition of hNKCC2A (r2 = 0.817; P < 0.01). Replacement of the carboxylic group of bumetanide by a non-ionic residue, for example, an anilinomethyl group, decreased inhibition of hNKCC2A, indicating that an acidic group was required for transporter inhibition. Exchange of the phenoxy group of bumetanide for a 4-chloroanilino group or the sulfamoyl group by a methylsulfonyl group resulted in compounds with higher potency to inhibit hNKCC2A than bumetanide. CONCLUSIONS AND IMPLICATIONS The X. laevis oocyte expression system used in these experiments allowed analysis of the structural requirements that determine relative potency of loop diuretics on human NKCC2 splice variants, and may lead to the discovery of novel high-ceiling diuretics.
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Affiliation(s)
- Kasper Lykke
- Department of Cellular and Molecular Medicine, University of CopenhagenCopenhagen, Denmark
| | - Kathrin Töllner
- Department of Pharmacology, Toxicology, and Pharmacy, University of Veterinary Medicine HannoverHannover, Germany
- Center for Systems NeuroscienceHannover, Germany
| | - Kerstin Römermann
- Department of Pharmacology, Toxicology, and Pharmacy, University of Veterinary Medicine HannoverHannover, Germany
- Center for Systems NeuroscienceHannover, Germany
| | - Peter W Feit
- Department of Pharmacology, Toxicology, and Pharmacy, University of Veterinary Medicine HannoverHannover, Germany
| | - Thomas Erker
- Department of Medicinal Chemistry, University of ViennaVienna, Austria
| | - Nanna MacAulay
- Department of Cellular and Molecular Medicine, University of CopenhagenCopenhagen, Denmark
| | - Wolfgang Löscher
- Department of Pharmacology, Toxicology, and Pharmacy, University of Veterinary Medicine HannoverHannover, Germany
- Center for Systems NeuroscienceHannover, Germany
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Kaji I, Akiba Y, Said H, Narimatsu K, Kaunitz JD. Luminal 5-HT stimulates colonic bicarbonate secretion in rats. Br J Pharmacol 2015; 172:4655-70. [PMID: 26061462 DOI: 10.1111/bph.13216] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2014] [Revised: 04/16/2015] [Accepted: 05/09/2015] [Indexed: 12/20/2022] Open
Abstract
BACKGROUND AND PURPOSE The bioactive monoamine 5-HT, implicated in the pathogenesis of functional gastrointestinal disorders, is abundantly synthesized and stored in rat proximal colonic mucosa and released to the gut lumen and subepithelial space. Despite much data regarding its expression and function, the effects of luminal 5-HT on colonic anion secretion have not been fully investigated. EXPERIMENTAL APPROACH We measured short-circuit current (Isc ) as an indicator of ion transport in mucosa-submucosa or mucosa-only preparations of rat proximal colon. Total CO2 output was measured in vitro and in vivo. Immunohistochemistry was performed to investigate the localization of 5-HT4 , NOS1 and NOS2. KEY RESULTS Luminal 5-HT gradually increased the amplitude and sustained the elevation of Isc . Luminal 5-HT-evoked ΔIsc was acetazolamide sensitive and HCO3 (-) dependent, consistent with cytosolic carbonic anhydrase-dependent electrogenic HCO3 (-) secretion, while not affected by tetrodotoxin (TTX), atropine or indomethacin. Pretreatment with the selective 5-HT4 antagonist GR113808, but not antagonists for 5-HT3 , 5-HT6 or 5-HT7 , inhibited luminal 5-HT-evoked ΔIsc . Furthermore, luminal cisapride and tegaserod increased Isc to the same extent as did 5-HT in the presence of indomethacin and TTX. Removal of the submucosa or pretreatment with NOS inhibitors enhanced luminal 5-HT-evoked ΔIsc , suggesting that NO synthesized in the submucosa suppresses mucosal anion secretion. NOS1 and NOS2 were immunostained in the submucosal neurons and glial cells respectively. Luminal 5-HT-evoked HCO3 (-) secretion was confirmed in vivo, inhibited by co-perfusion of GR113808, but not by ondansetron. CONCLUSIONS AND IMPLICATIONS A novel apical 5-HT4 -mediated HCO3 (-) secretory pathway and an NO-dependent inhibitory mechanism are present in the proximal colon. Luminal 5-HT-evoked HCO3 (-) secretion may be important for the maintenance of mucosal integrity by regulating luminal pH.
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Affiliation(s)
- I Kaji
- Department of Medicine, University of California, Los Angeles, CA, USA.,Brentwood Biomedical Research Institute, Los Angeles, CA, USA
| | - Y Akiba
- Department of Medicine, University of California, Los Angeles, CA, USA.,Brentwood Biomedical Research Institute, Los Angeles, CA, USA.,Greater Los Angeles Veterans Affairs Healthcare System, CA, USA
| | - H Said
- College of Letters and Sciences, University of California, Los Angeles, CA, USA
| | - K Narimatsu
- Department of Medicine, University of California, Los Angeles, CA, USA
| | - J D Kaunitz
- Department of Medicine, University of California, Los Angeles, CA, USA.,Department of Surgery, School of Medicine, University of California, Los Angeles, CA, USA.,Brentwood Biomedical Research Institute, Los Angeles, CA, USA.,Greater Los Angeles Veterans Affairs Healthcare System, CA, USA
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Gruden G, Barutta F, Kunos G, Pacher P. Role of the endocannabinoid system in diabetes and diabetic complications. Br J Pharmacol 2015; 173:1116-27. [PMID: 26076890 DOI: 10.1111/bph.13226] [Citation(s) in RCA: 97] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2014] [Revised: 05/04/2015] [Accepted: 06/07/2015] [Indexed: 01/04/2023] Open
Abstract
UNLABELLED Increasing evidence suggests that an overactive endocannabinoid system (ECS) may contribute to the development of diabetes by promoting energy intake and storage, impairing both glucose and lipid metabolism, by exerting pro-apoptotic effects in pancreatic beta cells and by facilitating inflammation in pancreatic islets. Furthermore, hyperglycaemia associated with diabetes has also been implicated in triggering perturbations of the ECS amplifying the pathological processes mentioned above, eventually culminating in a vicious circle. Compelling evidence from preclinical studies indicates that the ECS also influences diabetes-induced oxidative stress, inflammation, fibrosis and subsequent tissue injury in target organs for diabetic complications. In this review, we provide an update on the contribution of the ECS to the pathogenesis of diabetes and diabetic microvascular (retinopathy, nephropathy and neuropathy) and cardiovascular complications. The therapeutic potential of targeting the ECS is also discussed. LINKED ARTICLES This article is part of a themed section on Endocannabinoids. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v173.7/issuetoc.
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Affiliation(s)
- G Gruden
- Laboratory of Diabetic Nephropathy, Department of Medical Sciences, University of Turin, Turin, Italy
| | - F Barutta
- Laboratory of Diabetic Nephropathy, Department of Medical Sciences, University of Turin, Turin, Italy
| | - G Kunos
- Laboratory of Physiologic Studies, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Bethesda, MA, USA
| | - P Pacher
- Laboratory of Physiologic Studies, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Bethesda, MA, USA
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Sampaio LS, Taveira Da Silva R, Lima D, Sampaio CLC, Iannotti FA, Mazzarella E, Di Marzo V, Vieyra A, Reis RAM, Einicker-Lamas M. The endocannabinoid system in renal cells: regulation of Na(+) transport by CB1 receptors through distinct cell signalling pathways. Br J Pharmacol 2015; 172:4615-25. [PMID: 25537261 DOI: 10.1111/bph.13050] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2014] [Revised: 06/22/2015] [Accepted: 06/29/2015] [Indexed: 12/31/2022] Open
Abstract
BACKGROUND AND PURPOSE The function of the endocannabinoid system (ECS) in renal tissue is not completely understood. Kidney function is closely related to ion reabsorption in the proximal tubule, the nephron segment responsible for the re-absorption of 70-80% of the filtrate. We studied the effect of compounds modulating the activity of cannabinoid (CB) receptors on the active re-absorption of Na(+) in LLC-PK1 cells. EXPERIMENTAL APPROACH Changes in Na(+) /K(+) -ATPase activity were assessed after treatment with WIN55,212-2 (WIN), a non-selective lipid agonist, and haemopressin (HP), an inverse peptide agonist at CB1 receptors. Pharmacological tools were used to investigate the signalling pathways involved in the modulation of Na(+) transport. KEY RESULTS In addition to CB1 and CB2 receptors and TRPV1 channels, the mRNAs encoding for enzymes of the ECS were also expressed in LLC-PK1. WIN (10(-7) M) and HP (10(-6) M) altered Na(+) re-absorption in LLC-PK1 in a dual manner. They both acutely (after 1 min) increased Na(+) /K(+) -ATPase activity in a TRPV1 antagonist-sensitive way. WIN's stimulating effect persisted for 30 min, and this effect was partially blocked by a CB1 antagonist or a PKC inhibitor. In contrast, HP inhibited Na(+) /K(+) -ATPase after 30 min incubation, and this effect was attenuated by a CB1 antagonist or a PKA inhibitor. CONCLUSION AND IMPLICATIONS The ECS is expressed in LLC-PK1 cells. Both CB1 receptors and TRPV1 channels regulate Na(+) /K(+) -ATPase activity in these cells, and are modulated by lipid and peptide CB1 receptor ligands, which act via different signalling pathways.
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Affiliation(s)
- L S Sampaio
- Instituto de Biofísica Carlos Chagas Filho, UFRJ, Rio de Janeiro, Brazil.,Instituto Nacional de Ciência e Tecnologia em Biologia Estrutural e Bioimagem, Brazil.,CAPES Foundation, Ministry of Education of Brasil, Brasilia, Brazil
| | - R Taveira Da Silva
- Instituto de Biofísica Carlos Chagas Filho, UFRJ, Rio de Janeiro, Brazil.,Instituto Nacional de Ciência e Tecnologia em Biologia Estrutural e Bioimagem, Brazil
| | - D Lima
- Instituto de Biofísica Carlos Chagas Filho, UFRJ, Rio de Janeiro, Brazil.,Instituto Nacional de Ciência e Tecnologia em Biologia Estrutural e Bioimagem, Brazil
| | - C L C Sampaio
- Instituto de Biofísica Carlos Chagas Filho, UFRJ, Rio de Janeiro, Brazil.,Instituto Nacional de Ciência e Tecnologia em Biologia Estrutural e Bioimagem, Brazil
| | - F A Iannotti
- Endocanabinnoid Research Group, Istituto di Chimica Biomolecolare, CNR, Pozzuoli, Italy
| | - E Mazzarella
- Endocanabinnoid Research Group, Istituto di Chimica Biomolecolare, CNR, Pozzuoli, Italy
| | - V Di Marzo
- Endocanabinnoid Research Group, Istituto di Chimica Biomolecolare, CNR, Pozzuoli, Italy
| | - A Vieyra
- Instituto de Biofísica Carlos Chagas Filho, UFRJ, Rio de Janeiro, Brazil.,Instituto Nacional de Ciência e Tecnologia em Biologia Estrutural e Bioimagem, Brazil.,CAPES Foundation, Ministry of Education of Brasil, Brasilia, Brazil
| | - R A M Reis
- Instituto de Biofísica Carlos Chagas Filho, UFRJ, Rio de Janeiro, Brazil.,Instituto Nacional de Ciência e Tecnologia em Neurociência Translacional, Brazil
| | - M Einicker-Lamas
- Instituto de Biofísica Carlos Chagas Filho, UFRJ, Rio de Janeiro, Brazil.,Instituto Nacional de Ciência e Tecnologia em Biologia Estrutural e Bioimagem, Brazil.,CAPES Foundation, Ministry of Education of Brasil, Brasilia, Brazil
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Lanzerstorfer P, Stadlbauer V, Chtcheglova LA, Haselgrübler R, Borgmann D, Wruss J, Hinterdorfer P, Schröder K, Winkler SM, Höglinger O, Weghuber J. Identification of novel insulin mimetic drugs by quantitative total internal reflection fluorescence (TIRF) microscopy. Br J Pharmacol 2015; 171:5237-51. [PMID: 25039620 PMCID: PMC4262000 DOI: 10.1111/bph.12845] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2014] [Revised: 06/18/2014] [Accepted: 06/27/2014] [Indexed: 12/25/2022] Open
Abstract
Background and Purpose Insulin stimulates the transport of glucose in target tissues by triggering the translocation of glucose transporter 4 (GLUT4) to the plasma membrane. Resistance to insulin, the major abnormality in type 2 diabetes, results in a decreased GLUT4 translocation efficiency. Thus, special attention is being paid to search for compounds that are able to enhance this translocation process in the absence of insulin. Experimental Approach Total internal reflection fluorescence (TIRF) microscopy was applied to quantify GLUT4 translocation in highly insulin-sensitive CHO-K1 cells expressing a GLUT4-myc-GFP fusion protein. Key Results Using our approach, we demonstrated GLUT4 translocation modulatory properties of selected substances and identified novel potential insulin mimetics. An increase in the TIRF signal was found to correlate with an elevated glucose uptake. Variations in the expression level of the human insulin receptor (hInsR) showed that the insulin mimetics identified stimulate GLUT4 translocation by a mechanism that is independent of the presence of the hInsR. Conclusions and Implications Taken together, the results indicate that TIRF microscopy is an excellent tool for the quantification of GLUT4 translocation and for identifying insulin mimetic drugs.
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Affiliation(s)
- Peter Lanzerstorfer
- School of Engineering and Environmental Sciences, University of Applied Sciences Upper Austria, Wels, Austria
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Liang J, Chao D, Sandhu HK, Yu Y, Zhang L, Balboni G, Kim DH, Xia Y. δ-Opioid receptors up-regulate excitatory amino acid transporters in mouse astrocytes. Br J Pharmacol 2015; 171:5417-30. [PMID: 25052197 DOI: 10.1111/bph.12857] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2013] [Revised: 07/07/2014] [Accepted: 07/17/2014] [Indexed: 12/13/2022] Open
Abstract
BACKGROUND AND PURPOSE Astrocytic excitatory amino acid transporters (EAATs) regulate extracellular glutamate concentrations and play a role in preventing neuroexcitotoxicity. As the δ-opioid receptor (DOP receptor) is neuroprotective against excitotoxic injury, we determined whether DOP receptor activation up-regulates EAAT expression and function. EXPERIMENTAL APPROACH We measured mRNA and protein expression of EAAT1, EAAT2 and EAAT3 in cultured mouse astrocytes exposed to a specific DOP receptor agonist (UFP-512) with or without a DOP receptor antagonist, DOP receptor siRNA or inhibitors of PKC, PKA, PI3K, p38, MAPK, MEK and ERK, and evaluated the function of EAATs by measuring glutamate uptake. KEY RESULTS Astrocytic DOP receptor mRNA and protein were suppressed by DOP receptor siRNA knockdown. DOP receptor activation increased mRNA and protein expression of EAAT1 and EAAT2, but not EAAT3, thereby enhancing glutamate uptake of astrocytes. DOP receptor-induced EAAT1 and EAAT2 expression was largely reversed by DOP receptor antagonist naltrindole or by DOP receptor siRNA knockdown, and suppressed by inhibitors of MEK, ERK and p38. DOP receptor-accelerated glutamate uptake was inhibited by EAAT blockers, DOP receptor siRNA knockdown or inhibitors of MEK, ERK or p38. In contrast, inhibitors of PKA, PKC or PI3K had no significant effect on DOP receptor-induced EAAT expression. CONCLUSIONS AND IMPLICATIONS DOP receptor activation up-regulates astrocytic EAATs via MEK-ERK-p38 signalling, suggesting a critical role for DOP receptors in the regulation of astrocytic EAATs and protection against neuroexcitotoxicity. As decreased EAAT expression contributes to pathophysiology in many neurological diseases, including amyotrophic lateral sclerosis, our findings present a new platform for potential treatments of these diseases.
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Affiliation(s)
- Jianfeng Liang
- Department of Neurosurgery, The University of Texas Medical School at Houston, Houston, TX, USA; Yale University School of Medicine, New Haven, CT, USA; Department of Neurosurgery, China-Japan Friendship Hospital, Beijing, China
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Chapy H, André P, Declèves X, Scherrmann JM, Cisternino S. A polyspecific drug/proton antiporter mediates diphenhydramine and clonidine transport at the mouse blood-retinal barrier. Br J Pharmacol 2015; 172:4714-25. [PMID: 26177775 DOI: 10.1111/bph.13246] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2015] [Revised: 06/11/2015] [Accepted: 07/03/2015] [Indexed: 12/18/2022] Open
Abstract
BACKGROUND AND PURPOSE Transporters at the blood-retinal barrier (BRB), as at the blood-brain barrier (BBB), regulate the distribution of compounds into the neural parenchyma. However, the expression of BRB transporters and their quantitative impact in vivo are still poorly understood. EXPERIMENTAL APPROACH Clonidine and diphenhydramine are substrates of a novel BBB drug/proton-antiporter. We evaluated their transport at the BRB by in situ carotid perfusion in wild-type or knocked-out mice for Oct1-3 (Slc22a1-3). KEY RESULTS At pharmacological exposure levels, carrier-mediated BRB influx was 2 and 12 times greater than the passive diffusion rate for clonidine and diphenhydramine, respectively. Functional identification demonstrated the involvement of a high-capacity potassium- and sodium-independent proton-antiporter that shared the features of the previously characterized clonidine, diphenhydramine and cocaine BBB transporter. The functional characterization suggests that SLC transporters Oct1-3, Mate1 (Slc47a1) and Octn1-2 (Slc22a4-5) are not involved. Melanin/retinal toxic drugs like antimalarials (amodiaquine, quinine), quinidine and tricyclic antidepressants (imipramine) acted as inhibitors of this proton-antiporter. The endogenous indole derivative tryptamine inhibited the transporter, unlike 5-HT (serotonin), dopamine or L-DOPA. Trans-stimulation experiments with [(3) H]-clonidine at the BRB indicated that diphenhydramine, nicotine, oxycodone, naloxone, tramadol, 3,4-methylenedioxyamphetamine (MDMA, ecstasy), heroin, methadone and verapamil are common substrates. CONCLUSIONS AND IMPLICATIONS A proton-antiporter is physiologically involved in the transport of clonidine and diphenhydramine and is quantitatively more important than their passive diffusion flux at the mouse BRB. The features of this molecularly unidentified transporter highlight its importance in regulating drug delivery at the retina and suggest that it has the capacity to handle several drugs.
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Affiliation(s)
- Hélène Chapy
- Variabilité de réponse aux psychotropes, INSERM U1144, Paris, France.,UMR-S 1144, Université Paris Descartes, Paris, France.,UMR-S 1144, Université Paris Diderot, Paris, France
| | - Pascal André
- Variabilité de réponse aux psychotropes, INSERM U1144, Paris, France.,UMR-S 1144, Université Paris Descartes, Paris, France.,UMR-S 1144, Université Paris Diderot, Paris, France
| | - Xavier Declèves
- Variabilité de réponse aux psychotropes, INSERM U1144, Paris, France.,UMR-S 1144, Université Paris Descartes, Paris, France.,UMR-S 1144, Université Paris Diderot, Paris, France.,Pharmacokinetics, Assistance Publique des Hôpitaux de Paris - AP-HP, Paris, France
| | - Jean-Michel Scherrmann
- Variabilité de réponse aux psychotropes, INSERM U1144, Paris, France.,UMR-S 1144, Université Paris Descartes, Paris, France.,UMR-S 1144, Université Paris Diderot, Paris, France.,Pharmacokinetics, Assistance Publique des Hôpitaux de Paris - AP-HP, Paris, France
| | - Salvatore Cisternino
- Variabilité de réponse aux psychotropes, INSERM U1144, Paris, France.,UMR-S 1144, Université Paris Descartes, Paris, France.,UMR-S 1144, Université Paris Diderot, Paris, France.,Pharmacokinetics, Assistance Publique des Hôpitaux de Paris - AP-HP, Paris, France
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Kozuka C, Sunagawa S, Ueda R, Higa M, Ohshiro Y, Tanaka H, Shimizu-Okabe C, Takayama C, Matsushita M, Tsutsui M, Ishiuchi S, Nakata M, Yada T, Miyazaki JI, Oyadomari S, Shimabukuro M, Masuzaki H. A novel insulinotropic mechanism of whole grain-derived γ-oryzanol via the suppression of local dopamine D 2 receptor signalling in mouse islet. Br J Pharmacol 2015; 172:4519-4534. [PMID: 26140534 DOI: 10.1111/bph.13236] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2015] [Revised: 06/16/2015] [Accepted: 06/20/2015] [Indexed: 01/13/2023] Open
Abstract
BACKGROUND AND PURPOSE γ-Oryzanol, derived from unrefined rice, attenuated the preference for dietary fat in mice, by decreasing hypothalamic endoplasmic reticulum stress. However, no peripheral mechanisms, whereby γ-oryzanol could ameliorate glucose dyshomeostasis were explored. Dopamine D2 receptor signalling locally attenuates insulin secretion in pancreatic islets, presumably via decreased levels of intracellular cAMP. We therefore hypothesized that γ-oryzanol would improve high-fat diet (HFD)-induced dysfunction of islets through the suppression of local D2 receptor signalling. EXPERIMENTAL APPROACH Glucose metabolism and regulation of molecules involved in D2 receptor signalling in pancreatic islets were investigated in male C57BL/6J mice, fed HFD and treated with γ-oryzanol . In isolated murine islets and the beta cell line, MIN6 , the effects of γ-oryzanol on glucose-stimulated insulin secretion (GSIS) was analysed using siRNA for D2 receptors and a variety of compounds which alter D2 receptor signalling. KEY RESULTS In islets, γ-oryzanol enhanced GSIS via the activation of the cAMP/PKA pathway. Expression of molecules involved in D2 receptor signalling was increased in islets from HFD-fed mice, which were reciprocally decreased by γ-oryzanol. Experiments with siRNA for D2 receptors and D2 receptor ligands in vitro suggest that γ-oryzanol suppressed D2 receptor signalling and augmented GSIS. CONCLUSIONS AND IMPLICATIONS γ-Oryzanol exhibited unique anti-diabetic properties. The unexpected effects of γ-oryzanol on D2 receptor signalling in islets may provide a novel; natural food-based, approach to anti-diabetic therapy.
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Affiliation(s)
- Chisayo Kozuka
- Division of Endocrinology, Diabetes and Metabolism, Hematology, Rheumatology (Second Department of Internal Medicine), University of the Ryukyus, Okinawa, Japan
| | - Sumito Sunagawa
- Division of Endocrinology, Diabetes and Metabolism, Hematology, Rheumatology (Second Department of Internal Medicine), University of the Ryukyus, Okinawa, Japan
| | - Rei Ueda
- Division of Endocrinology, Diabetes and Metabolism, Hematology, Rheumatology (Second Department of Internal Medicine), University of the Ryukyus, Okinawa, Japan
| | - Moritake Higa
- Division of Endocrinology, Diabetes and Metabolism, Hematology, Rheumatology (Second Department of Internal Medicine), University of the Ryukyus, Okinawa, Japan.,The Diabetes and Life-Style Related Disease Center, Tomishiro Central Hospital, Okinawa, Japan
| | - Yuzuru Ohshiro
- Division of Endocrinology, Diabetes and Metabolism, Hematology, Rheumatology (Second Department of Internal Medicine), University of the Ryukyus, Okinawa, Japan.,Okinawa Daiichi Hospital, Okinawa, Japan
| | - Hideaki Tanaka
- Division of Endocrinology, Diabetes and Metabolism, Hematology, Rheumatology (Second Department of Internal Medicine), University of the Ryukyus, Okinawa, Japan.,Tanaka Clinic, Okinawa, Japan
| | - Chigusa Shimizu-Okabe
- Department of Molecular Anatomy, Graduate School of Medicine, University of the Ryukyus, Okinawa, Japan
| | - Chitoshi Takayama
- Department of Molecular Anatomy, Graduate School of Medicine, University of the Ryukyus, Okinawa, Japan
| | - Masayuki Matsushita
- Department of Molecular and Cellular Physiology, Graduate School of Medicine, University of the Ryukyus, Okinawa, Japan
| | - Masato Tsutsui
- Department of Pharmacology, Graduate School of Medicine, University of the Ryukyus, Okinawa, Japan
| | - Shogo Ishiuchi
- Department of Neurosurgery, Graduate School of Medicine, University of the Ryukyus, Okinawa, Japan
| | - Masanori Nakata
- Division of Integrative Physiology, Department of Physiology, Jichi Medical University School of Medicine, Tochigi, Japan
| | - Toshihiko Yada
- Division of Integrative Physiology, Department of Physiology, Jichi Medical University School of Medicine, Tochigi, Japan
| | - Jun-Ichi Miyazaki
- Division of Stem Cell Regulation Research, Osaka University Graduate School of Medicine, Osaka, Japan
| | - Seiichi Oyadomari
- Institute for Genome Research, University of Tokushima, Tokushima, Japan
| | - Michio Shimabukuro
- Department of Cardio-Diabetes Medicine, Institute of Biomedical Sciences, Tokushima University Graduate School, Tokushima, Japan
| | - Hiroaki Masuzaki
- Division of Endocrinology, Diabetes and Metabolism, Hematology, Rheumatology (Second Department of Internal Medicine), University of the Ryukyus, Okinawa, Japan
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45
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Chang GR, Chiu YS, Wu YY, Lin YC, Hou PH, Mao FC. Rapamycin impairs HPD-induced beneficial effects on glucose homeostasis. Br J Pharmacol 2015; 172:3793-804. [PMID: 25884889 PMCID: PMC4523336 DOI: 10.1111/bph.13168] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2014] [Revised: 03/08/2015] [Accepted: 04/07/2015] [Indexed: 12/21/2022] Open
Abstract
BACKGROUND AND PURPOSE Rapamycin, which is used clinically to treat graft rejection, has also been proposed to have an effect on metabolic syndrome; however, very little information is available on its effects in lean animals/humans. The purpose of this study was to characterize further the effects of the continuous use of rapamycin on glucose homeostasis in lean C57BL6/J mice. EXPERIMENTAL APPROACH Mice were fed a high-protein diet (HPD) for 12 weeks to develop a lean model and then were treated daily with rapamycin for 5 weeks while remaining on a HPD. Metabolic parameters, endocrine profiles, glucose tolerance tests, insulin sensitivity index, the expression of the glucose transporter GLUT4 and chromium distribution were measured in vivo. KEY RESULTS Lower body weight gain as well as a decreased caloric intake, fat pads, fatty liver scores, adipocyte size and glucose tolerance test values were observed in HPD-fed mice compared with mice fed a high-fat or standard diet. Despite these beneficial effects, rapamycin-treated lean mice showed greater glucose intolerance, reduced insulin sensitivity, lower muscle GLUT4 expression and changes in chromium levels in tissues even with high insulin levels. CONCLUSION AND IMPLICATIONS Our findings demonstrate that continuous rapamycin administration may lead to the development of diabetes syndrome, as it was found to induce hyperglycaemia and glucose intolerance in a lean animal model.
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Affiliation(s)
- Geng-Ruei Chang
- Department of Veterinary Medicine, National Chung Hsing UniversityTaichung, Taiwan
- Division of Residual Control, Agricultural Chemicals and Toxic Substance Research Institute, Council of AgricultureTaichung, Taiwan
| | - Yi-Shin Chiu
- Department of Veterinary Medicine, National Chung Hsing UniversityTaichung, Taiwan
| | - Ying-Ying Wu
- Department of Veterinary Medicine, National Chung Hsing UniversityTaichung, Taiwan
| | - Yu-Chi Lin
- Department of Veterinary Medicine, National Chung Hsing UniversityTaichung, Taiwan
| | - Po-Hsun Hou
- Department of Veterinary Medicine, National Chung Hsing UniversityTaichung, Taiwan
- Department of Psychiatry, Taichung Veterans General HospitalTaichung, Taiwan
| | - Frank Chiahung Mao
- Department of Veterinary Medicine, National Chung Hsing UniversityTaichung, Taiwan
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García C, Palomo-Garo C, Gómez-Gálvez Y, Fernández-Ruiz J. Cannabinoid-dopamine interactions in the physiology and physiopathology of the basal ganglia. Br J Pharmacol 2015; 173:2069-79. [PMID: 26059564 DOI: 10.1111/bph.13215] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2015] [Revised: 05/05/2015] [Accepted: 06/02/2015] [Indexed: 01/09/2023] Open
Abstract
UNLABELLED Endocannabinoids and their receptors play a modulatory role in the control of dopamine transmission in the basal ganglia. However, this influence is generally indirect and exerted through the modulation of GABA and glutamate inputs received by nigrostriatal dopaminergic neurons, which lack cannabinoid CB1 receptors although they may produce endocannabinoids. Additional evidence suggests that CB2 receptors may be located in nigrostriatal dopaminergic neurons, and that certain eicosanoid-related cannabinoids may directly activate TRPV1 receptors, which have been found in nigrostriatal dopaminergic neurons, thus allowing in both cases a direct regulation of dopamine transmission by specific cannabinoids. In addition, CB1 receptors form heteromers with dopaminergic receptors which provide another pathway to direct interactions between both systems, in this case at the postsynaptic level. Through these direct mechanisms or through indirect mechanisms involving GABA or glutamate neurons, cannabinoids may interact with dopaminergic transmission in the basal ganglia and this is likely to have important effects on dopamine-related functions in these structures (i.e. control of movement) and, particularly, on different pathologies affecting these processes, in particular, Parkinson's disease, but also dyskinesia, dystonia and other pathological conditions. The present review will address the current literature supporting these cannabinoid-dopamine interactions at the basal ganglia, with emphasis on aspects dealing with the physiopathological consequences of these interactions. LINKED ARTICLES This article is part of a themed section on Updating Neuropathology and Neuropharmacology of Monoaminergic Systems. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v173.13/issuetoc.
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Affiliation(s)
- Concepción García
- Departamento de Bioquímica y Biología Molecular, Instituto Universitario de Investigación en Neuroquímica, Facultad de Medicina, Universidad Complutense, Madrid, Spain.,Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), Madrid, Spain.,Instituto Ramón y Cajal de Investigación Sanitaria (IRYCIS), Madrid, Spain
| | - Cristina Palomo-Garo
- Departamento de Bioquímica y Biología Molecular, Instituto Universitario de Investigación en Neuroquímica, Facultad de Medicina, Universidad Complutense, Madrid, Spain.,Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), Madrid, Spain.,Instituto Ramón y Cajal de Investigación Sanitaria (IRYCIS), Madrid, Spain
| | - Yolanda Gómez-Gálvez
- Departamento de Bioquímica y Biología Molecular, Instituto Universitario de Investigación en Neuroquímica, Facultad de Medicina, Universidad Complutense, Madrid, Spain.,Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), Madrid, Spain.,Instituto Ramón y Cajal de Investigación Sanitaria (IRYCIS), Madrid, Spain
| | - Javier Fernández-Ruiz
- Departamento de Bioquímica y Biología Molecular, Instituto Universitario de Investigación en Neuroquímica, Facultad de Medicina, Universidad Complutense, Madrid, Spain.,Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), Madrid, Spain.,Instituto Ramón y Cajal de Investigación Sanitaria (IRYCIS), Madrid, Spain
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47
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Singh NS, Bernier M, Camandola S, Khadeer MA, Moaddel R, Mattson MP, Wainer IW. Enantioselective inhibition of d-serine transport by (S)-ketamine. Br J Pharmacol 2015; 172:4546-4559. [PMID: 26140427 DOI: 10.1111/bph.13239] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2014] [Revised: 06/26/2015] [Accepted: 06/28/2015] [Indexed: 12/23/2022] Open
Abstract
BACKGROUND AND PURPOSE Patients with major depressive disorder receiving racemic ketamine, (R,S)-ketamine, experience transient increases in Clinician-Administered Dissociative States Scale scores and a coincident drop in plasma d-serine levels. The results suggest that (R,S)-ketamine produces an immediate, concentration-dependent pharmacological effect on d-serine plasma concentrations. One potential source of this effect is (R,S)-ketamine-induced inhibition of the transporter ASCT2, which regulates intracellular d-serine concentrations. In this study, we tested this hypothesis by examining the effect of (S)- and (R)-ketamine on ASCT2-mediated transport of d-serine in PC-12 and 1321N1 cells and primary neuronal cells in culture. EXPERIMENTAL APPROACH Intracellular and extracellular d-serine levels were determined using capillary electrophoresis-laser-induced fluorescence and liquid chromatography-mass spectrometry respectively. Expression of ASCT2, Asc-1 and serine racemase was determined utilizing Western blotting. KEY RESULTS (S)-Ketamine produced a concentration-dependent increase in intracellular d-serine and reduced extracellular d-serine accumulation. In contrast, (R)-ketamine decreased both intracellular and extracellular d-serine levels. The ASCT2 inhibitor, benzyl-d-serine (BDS), and ASCT2 gene knockdown mimicked the action of (S)-ketamine on d-serine in PC-12 cells, while the Asc-1 agonist d-isoleucine reduced intracellular d-serine and increased extracellular d-serine accumulation. This response to d-isoleucine was not affected by BDS or (S)-ketamine. Primary cultures of rat neuronal cells expressed ASCT2 and were responsive to (S)-ketamine and BDS. (S)- and (R)-ketamine increased the expression of monomeric serine racemase in all the cells studied, with (S)-ketamine having the greatest effect. CONCLUSIONS AND IMPLICATIONS (S)-Ketamine decreased cellular export of d-serine via selective inhibition of ASCT2, and this could represent a possible source of dissociative effects observed with (R,S)-ketamine.
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Affiliation(s)
- Nagendra S Singh
- Laboratory of Clinical Investigation, National Institute on Aging Intramural Research Program, National Institutes of Health, Baltimore, MD, USA
| | - Michel Bernier
- Translational Gerontology Branch, National Institute on Aging Intramural Research Program, National Institutes of Health, Baltimore, MD, USA
| | - Simonetta Camandola
- Laboratory of Neurosciences, National Institute on Aging Intramural Research Program, National Institutes of Health, Baltimore, MD, USA
| | - Mohammed A Khadeer
- Laboratory of Clinical Investigation, National Institute on Aging Intramural Research Program, National Institutes of Health, Baltimore, MD, USA
| | - Ruin Moaddel
- Laboratory of Clinical Investigation, National Institute on Aging Intramural Research Program, National Institutes of Health, Baltimore, MD, USA
| | - Mark P Mattson
- Laboratory of Neurosciences, National Institute on Aging Intramural Research Program, National Institutes of Health, Baltimore, MD, USA
| | - Irving W Wainer
- Laboratory of Clinical Investigation, National Institute on Aging Intramural Research Program, National Institutes of Health, Baltimore, MD, USA
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Eckle VS, Grasshoff C, Mirakaj V, O'Neill PM, Berry NG, Leuwer M, Antkowiak B. 4-bromopropofol decreases action potential generation in spinal neurons by inducing a glycine receptor-mediated tonic conductance. Br J Pharmacol 2015; 171:5790-801. [PMID: 25131750 DOI: 10.1111/bph.12880] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2014] [Revised: 07/29/2014] [Accepted: 08/11/2014] [Indexed: 01/01/2023] Open
Abstract
BACKGROUND AND PURPOSE Impaired function of spinal strychnine-sensitive glycine receptors gives rise to chronic pain states and movement disorders. Therefore, increased activity of glycine receptors should help to treat such disorders. Although compounds targeting glycine receptors with a high selectivity are lacking, halogenated analogues of propofol have recently been considered as potential candidates. Therefore we asked whether 4-bromopropofol attenuated the excitability of spinal neurons by promoting glycine receptor-dependent inhibition. EXPERIMENTAL APPROACH The actions of sub-anaesthetic concentrations of propofol and 4-bromopropofol were investigated in spinal tissue cultures prepared from mice. Drug-induced alterations in action potential firing were monitored by extracellular multi-unit recordings. The effects on GABAA and glycine receptor-mediated inhibition were quantified by whole-cell voltage-clamp recordings. KEY RESULTS Low concentrations of 4-bromopropofol (50 nM) reduced action potential activity of ventral horn neurons by about 30%, compared with sham-treated slices. This effect was completely abolished by strychnine (1 μM). In voltage-clamped neurons, 4-bromopropofol activated glycine receptors, generating a tonic current of 65 ± 10 pA, while GABAA - and glycine receptor-mediated synaptic transmission remained unaffected. CONCLUSIONS AND IMPLICATIONS The highest glycine levels in the CNS are found in the ventral horn of the spinal cord, a region mediating pain-induced motor reflexes and participating in the control of muscle tone. 4-Bromopropofol may serve as a starting point for the development of non-sedative, non-addictive, muscle relaxants and analgesics to be used to treat low back pain.
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Affiliation(s)
- V S Eckle
- Experimental Anaesthesiology Section, Department of Anaesthesiology and Intensive Care, Eberhard-Karls-University, Tübingen, Germany
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49
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Wrasidlo W, Crews LA, Tsigelny IF, Stocking E, Kouznetsova VL, Price D, Paulino A, Gonzales T, Overk CR, Patrick C, Rockenstein E, Masliah E. Neuroprotective effects of the anti-cancer drug sunitinib in models of HIV neurotoxicity suggests potential for the treatment of neurodegenerative disorders. Br J Pharmacol 2015; 171:5757-73. [PMID: 25117211 DOI: 10.1111/bph.12875] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2014] [Revised: 07/30/2014] [Accepted: 08/03/2014] [Indexed: 12/12/2022] Open
Abstract
BACKGROUND AND PURPOSE Anti-retrovirals have improved and extended the life expectancy of patients with HIV. However, as this population ages, the prevalence of cognitive changes is increasing. Aberrant activation of kinases, such as receptor tyrosine kinases (RTKs) and cyclin-dependent kinase 5 (CDK5), play a role in the mechanisms of HIV neurotoxicity. Inhibitors of CDK5, such as roscovitine, have neuroprotective effects; however, CNS penetration is low. Interestingly, tyrosine kinase inhibitors (TKIs) display some CDK inhibitory activity and ability to cross the blood-brain barrier. EXPERIMENTAL APPROACH We screened a small group of known TKIs for a candidate with additional CDK5 inhibitory activity and tested the efficacy of the candidate in in vitro and in vivo models of HIV-gp120 neurotoxicity. KEY RESULTS Among 12 different compounds, sunitinib inhibited CDK5 with an IC50 of 4.2 μM. In silico analysis revealed that, similarly to roscovitine, sunitinib fitted 6 of 10 features of the CDK5 pharmacophore. In a cell-based model, sunitinib reduced CDK5 phosphorylation (pCDK5), calpain-dependent p35/p25 conversion and protected neuronal cells from the toxic effects of gp120. In glial fibrillary acidic protein-gp120 transgenic (tg) mice, sunitinib reduced levels of pCDK5, p35/p25 and phosphorylated tau protein, along with amelioration of the neurodegenerative pathology. CONCLUSIONS AND IMPLICATIONS Compounds such as sunitinib with dual kinase inhibitory activity could ameliorate the cognitive impairment associated with chronic HIV infection of the CNS. Moreover, repositioning existing low MW compounds holds promise for the treatment of patients with neurodegenerative disorders.
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Affiliation(s)
- Wolf Wrasidlo
- Department of Neurosciences, University of California, San Diego, CA, USA
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50
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Nagy N, Kormos A, Kohajda Z, Szebeni Á, Szepesi J, Pollesello P, Levijoki J, Acsai K, Virág L, Nánási PP, Papp JG, Varró A, Tóth A. Selective Na(+) /Ca(2+) exchanger inhibition prevents Ca(2+) overload-induced triggered arrhythmias. Br J Pharmacol 2015; 171:5665-81. [PMID: 25073832 DOI: 10.1111/bph.12867] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2014] [Revised: 07/03/2014] [Accepted: 07/25/2014] [Indexed: 01/23/2023] Open
Abstract
BACKGROUND AND PURPOSE Augmented Na(+) /Ca(2+) exchanger (NCX) activity may play a crucial role in cardiac arrhythmogenesis; however, data regarding the anti-arrhythmic efficacy of NCX inhibition are debatable. Feasible explanations could be the unsatisfactory selectivity of NCX inhibitors and/or the dependence of the experimental model on the degree of Ca(2+) i overload. Hence, we used NCX inhibitors SEA0400 and the more selective ORM10103 to evaluate the efficacy of NCX inhibition against arrhythmogenic Ca(2+) i rise in conditions when [Ca(2+) ]i was augmented via activation of the late sodium current (INaL ) or inhibition of the Na(+) /K(+) pump. EXPERIMENTAL APPROACH Action potentials (APs) were recorded from canine papillary muscles and Purkinje fibres by microelectrodes. NCX current (INCX ) was determined in ventricular cardiomyocytes utilizing the whole-cell patch clamp technique. Ca(2+) i transients (CaTs) were monitored with a Ca(2+) -sensitive fluorescent dye, Fluo-4. KEY RESULTS Enhanced INaL increased the Ca(2+) load and AP duration (APD). SEA0400 and ORM10103 suppressed INCX and prevented/reversed the anemone toxin II (ATX-II)-induced [Ca(2+) ]i rise without influencing APD, CaT or cell shortening, or affecting the ATX-II-induced increased APD. ORM10103 significantly decreased the number of strophanthidin-induced spontaneous diastolic Ca(2+) release events; however, SEA0400 failed to restrict the veratridine-induced augmentation in Purkinje-ventricle APD dispersion. CONCLUSIONS AND IMPLICATIONS Selective NCX inhibition - presumably by blocking rev INCX (reverse mode NCX current) - is effective against arrhythmogenesis caused by [Na(+) ]i -induced [Ca(2+) ]i elevation, without influencing the AP waveform. Therefore, selective INCX inhibition, by significantly reducing the arrhythmogenic trigger activity caused by the perturbed Ca(2+) i handling, should be considered as a promising anti-arrhythmic therapeutic strategy.
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Affiliation(s)
- Norbert Nagy
- MTA-SZTE Research Group of Cardiovascular Pharmacology, Hungarian Academy of Sciences, Szeged, Hungary
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