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Mezache L, Soltisz AM, Johnstone SR, Isakson BE, Veeraraghavan R. Vascular Endothelial Barrier Protection Prevents Atrial Fibrillation by Preserving Cardiac Nanostructure. JACC Clin Electrophysiol 2023; 9:2444-2458. [PMID: 38032579 PMCID: PMC11134328 DOI: 10.1016/j.jacep.2023.10.013] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2023] [Revised: 10/20/2023] [Accepted: 10/21/2023] [Indexed: 12/01/2023]
Abstract
BACKGROUND Atrial fibrillation (AF), the most common cardiac arrhythmia, is widely associated with inflammation, vascular dysfunction, and elevated levels of the vascular leak-inducing cytokine, vascular endothelial growth factor (VEGF). Mechanisms underlying AF are poorly understood and current treatments only manage this progressive disease, rather than arresting the underlying pathology. The authors previously identified edema-induced disruption of sodium channel (NaV1.5)-rich intercalated disk nanodomains as a novel mechanism for AF initiation secondary to acute inflammation. Therefore, we hypothesized that protecting the vascular barrier can prevent vascular leak-induced atrial arrhythmias. OBJECTIVES In this study the authors tested the hypothesis that protecting the vascular barrier can prevent vascular leak-induced atrial arrhythmias. They identified 2 molecular targets for vascular barrier protection, connexin43 (Cx43) hemichannels and pannexin-1 (Panx1) channels, which have been implicated in cytokine-induced vascular leak. METHODS The authors undertook in vivo electrocardiography, electron microscopy, and super-resolution light microscopy studies in mice acutely treated with a clinically relevant level of VEGF. RESULTS AF incidence was increased in untreated mice exposed to VEGF relative to vehicle control subjects. VEGF also increased the average number of AF episodes. VEGF shifted NaV1.5 signal to longer distances from Cx43 gap junctions, measured by a distance transformation-based spatial analysis of 3-dimensional confocal images of intercalated disks. Similar effects were observed with NaV1.5 localized near mechanical junctions composed of neural cadherin. Blocking connexin43 hemichannels (αCT11 peptide) or Panx1 channels (PxIL2P peptide) significantly reduced the duration of AF episodes compared with VEGF alone with no treatment. Concurrently, both peptide therapies preserved NaV1.5 distance from gap junctions to control levels and reduced mechanical junction-adjacent intermembrane distance in these hearts. Notably, similar antiarrhythmic efficacy was also achieved with clinically-relevant small-molecule inhibitors of Cx43 and Panx1. CONCLUSIONS These results highlight vascular barrier protection as an antiarrhythmic strategy following inflammation-induced vascular leak.
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Affiliation(s)
- Louisa Mezache
- Department of Biomedical Engineering, College of Engineering, The Ohio State University, Columbus, Ohio, USA
| | - Andrew M Soltisz
- Department of Biomedical Engineering, College of Engineering, The Ohio State University, Columbus, Ohio, USA
| | - Scott R Johnstone
- Fralin Biomedical Research Institute at VTC, Centre for Vascular and Heart Research, Virginia Tech, Roanoke, Virginia, USA; Department of Biological Sciences, Virginia Tech, Blacksburg, Virginia, USA; Virginia Tech Carilion School of Medicine, Department of Surgery, Roanoke, Virginia, USA
| | - Brant E Isakson
- Department of Molecular Physiology and Biological Physics, School of Medicine, University of Virginia, Charlottesville, Virginia, USA; Robert M. Berne Cardiovascular Research Center, University of Virginia School of Medicine, Charlottesville, Virginia, USA
| | - Rengasayee Veeraraghavan
- Department of Biomedical Engineering, College of Engineering, The Ohio State University, Columbus, Ohio, USA; The Frick Center for Heart Failure and Arrhythmia, Dorothy M. Davis Heart and Lung Research Institute, College of Medicine, The Ohio State University Wexner Medical Center, Columbus, Ohio, USA; Department of Physiology and Cell Biology, College of Medicine, The Ohio State University, Columbus, Ohio, USA.
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2
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Wattanakul T, Chotsiri P, Scandale I, Hoglund RM, Tarning J. A pharmacometric approach to evaluate drugs for potential repurposing as COVID-19 therapeutics. Expert Rev Clin Pharmacol 2022; 15:945-958. [PMID: 36017624 DOI: 10.1080/17512433.2022.2113388] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
INTRODUCTION Developing and evaluating novel compounds for treatment or prophylaxis of emerging infectious diseases is costly and time-consuming. Repurposing of already available marketed compounds is an appealing option as they already have an established safety profile. This approach could substantially reduce cost and time required to make effective treatments available to fight the COVID-19 pandemic. However, this approach is challenging since many drug candidates show efficacy in in vitro experiments, but fail to deliver effect when evaluated in clinical trials. Better approaches to evaluate in vitro data are needed, in order to prioritize drugs for repurposing. AREAS COVERED This article evaluates potential drugs that might be of interest for repurposing in the treatment of patients with COVID-19 disease. A pharmacometric simulation-based approach was developed to evaluate in vitro activity data in combination with expected clinical drug exposure, in order to evaluate the likelihood of achieving effective concentrations in patients. EXPERT OPINION The presented pharmacometric approach bridges in vitro activity data to clinically expected drug exposures, and could therefore be a useful compliment to other methods in order to prioritize repurposed drugs for evaluation in prospective randomized controlled clinical trials.
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Affiliation(s)
- Thanaporn Wattanakul
- Mahidol-Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand
| | - Palang Chotsiri
- Mahidol-Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand
| | - Ivan Scandale
- Drugs for Neglected Diseases Initiative, Geneva, Switzerland
| | - Richard M Hoglund
- Mahidol-Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand.,Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of Oxford, Oxford, UK
| | - Joel Tarning
- Mahidol-Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand.,Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of Oxford, Oxford, UK
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3
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Aherfi S, Pradines B, Devaux C, Honore S, Colson P, Scola BL, Raoult D. Drug repurposing against SARS-CoV-1, SARS-CoV-2 and MERS-CoV. Future Microbiol 2021; 16:1341-1370. [PMID: 34755538 PMCID: PMC8579950 DOI: 10.2217/fmb-2021-0019] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2021] [Accepted: 10/08/2021] [Indexed: 12/13/2022] Open
Abstract
Since the beginning of the COVID-19 pandemic, large in silico screening studies and numerous in vitro studies have assessed the antiviral activity of various drugs on SARS-CoV-2. In the context of health emergency, drug repurposing represents the most relevant strategy because of the reduced time for approval by international medicines agencies, the low cost of development and the well-known toxicity profile of such drugs. Herein, we aim to review drugs with in vitro antiviral activity against SARS-CoV-2, combined with molecular docking data and results from preliminary clinical studies. Finally, when considering all these previous findings, as well as the possibility of oral administration, 11 molecules consisting of nelfinavir, favipiravir, azithromycin, clofoctol, clofazimine, ivermectin, nitazoxanide, amodiaquine, heparin, chloroquine and hydroxychloroquine, show an interesting antiviral activity that could be exploited as possible drug candidates for COVID-19 treatment.
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Affiliation(s)
- Sarah Aherfi
- Aix-Marseille Université, Assistance Publique – Hôpitaux de Marseille (AP-HM), Marseille, 13005, France
- Institut Hospitalo-Universitaire (IHU) – Méditerranée Infection, Marseille, 13005, France
- Microbes, Evolution, Phylogeny & Infection (MEΦI), Marseille, 13005, France
| | - Bruno Pradines
- Institut Hospitalo-Universitaire (IHU) – Méditerranée Infection, Marseille, 13005, France
- Unité Parasitologie et Entomologie, Département Microbiologie et Maladies Infectieuses, Institut de Recherche Biomédicale des Armées, Marseille, 13005, France
- Aix-Marseille Univ, IRD, SSA, AP-HM, VITROME, Marseille, 13005, France
- Centre national de référence du paludisme, Marseille, 13005, France
| | - Christian Devaux
- Institut Hospitalo-Universitaire (IHU) – Méditerranée Infection, Marseille, 13005, France
| | - Stéphane Honore
- Aix Marseille Université, Laboratoire de Pharmacie Clinique, Marseille, 13005, France
- AP-HM, hôpital Timone, service pharmacie, Marseille, 13005, France
| | - Philippe Colson
- Aix-Marseille Université, Assistance Publique – Hôpitaux de Marseille (AP-HM), Marseille, 13005, France
- Institut Hospitalo-Universitaire (IHU) – Méditerranée Infection, Marseille, 13005, France
- Microbes, Evolution, Phylogeny & Infection (MEΦI), Marseille, 13005, France
| | - Bernard La Scola
- Aix-Marseille Université, Assistance Publique – Hôpitaux de Marseille (AP-HM), Marseille, 13005, France
- Institut Hospitalo-Universitaire (IHU) – Méditerranée Infection, Marseille, 13005, France
- Microbes, Evolution, Phylogeny & Infection (MEΦI), Marseille, 13005, France
| | - Didier Raoult
- Aix-Marseille Université, Assistance Publique – Hôpitaux de Marseille (AP-HM), Marseille, 13005, France
- Institut Hospitalo-Universitaire (IHU) – Méditerranée Infection, Marseille, 13005, France
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In Vitro Evaluation of the Antiviral Activity of Methylene Blue Alone or in Combination against SARS-CoV-2. J Clin Med 2021; 10:jcm10143007. [PMID: 34300178 PMCID: PMC8307868 DOI: 10.3390/jcm10143007] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2021] [Revised: 07/01/2021] [Accepted: 07/02/2021] [Indexed: 12/23/2022] Open
Abstract
A new severe acute respiratory syndrome coronavirus (SARS-CoV-2) causing coronavirus diseases 2019 (COVID-19), which emerged in Wuhan, China in December 2019, has spread worldwide. Currently, very few treatments are officially recommended against SARS-CoV-2. Identifying effective, low-cost antiviral drugs with limited side effects that are affordable immediately is urgently needed. Methylene blue, a synthesized thiazine dye, may be a potential antiviral drug. Antiviral activity of methylene blue used alone or in combination with several antimalarial drugs or remdesivir was assessed against infected Vero E6 cells infected with two clinically isolated SARS-CoV-2 strains (IHUMI-3 and IHUMI-6). Effects both on viral entry in the cell and on post-entry were also investigated. After 48 h post-infection, the viral replication was estimated by RT-PCR. The median effective concentration (EC50) and 90% effective concentration (EC90) of methylene blue against IHUMI-3 were 0.41 ± 0.34 µM and 1.85 ± 1.41 µM, respectively; 1.06 ± 0.46 µM and 5.68 ± 1.83 µM against IHUMI-6. Methylene blue interacted at both entry and post-entry stages of SARS-CoV-2 infection in Vero E6 cells as retrieved for hydroxychloroquine. The effects of methylene blue were additive with those of quinine, mefloquine and pyronaridine. The combinations of methylene blue with chloroquine, hydroxychloroquine, desethylamodiaquine, piperaquine, lumefantrine, ferroquine, dihydroartemisinin and remdesivir were antagonist. These results support the potential interest of methylene blue to treat COVID-19.
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5
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Shionoya K, Yamasaki M, Iwanami S, Ito Y, Fukushi S, Ohashi H, Saso W, Tanaka T, Aoki S, Kuramochi K, Iwami S, Takahashi Y, Suzuki T, Muramatsu M, Takeda M, Wakita T, Watashi K. Mefloquine, a Potent Anti-severe Acute Respiratory Syndrome-Related Coronavirus 2 (SARS-CoV-2) Drug as an Entry Inhibitor in vitro. Front Microbiol 2021; 12:651403. [PMID: 33995308 PMCID: PMC8119653 DOI: 10.3389/fmicb.2021.651403] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2021] [Accepted: 04/06/2021] [Indexed: 12/30/2022] Open
Abstract
Coronavirus disease 2019 (COVID-19) has caused serious public health, social, and economic damage worldwide and effective drugs that prevent or cure COVID-19 are urgently needed. Approved drugs including Hydroxychloroquine, Remdesivir or Interferon were reported to inhibit the infection or propagation of severe acute respiratory syndrome-related coronavirus 2 (SARS-CoV-2), however, their clinical efficacies have not yet been well demonstrated. To identify drugs with higher antiviral potency, we screened approved anti-parasitic/anti-protozoal drugs and identified an anti-malarial drug, Mefloquine, which showed the highest anti-SARS-CoV-2 activity among the tested compounds. Mefloquine showed higher anti-SARS-CoV-2 activity than Hydroxychloroquine in VeroE6/TMPRSS2 and Calu-3 cells, with IC50 = 1.28 μM, IC90 = 2.31 μM, and IC99 = 4.39 μM in VeroE6/TMPRSS2 cells. Mefloquine inhibited viral entry after viral attachment to the target cell. Combined treatment with Mefloquine and Nelfinavir, a replication inhibitor, showed synergistic antiviral activity. Our mathematical modeling based on the drug concentration in the lung predicted that Mefloquine administration at a standard treatment dosage could decline viral dynamics in patients, reduce cumulative viral load to 7% and shorten the time until virus elimination by 6.1 days. These data cumulatively underscore Mefloquine as an anti-SARS-CoV-2 entry inhibitor.
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Affiliation(s)
- Kaho Shionoya
- Department of Virology II, National Institute of Infectious Diseases, Tokyo, Japan.,Department of Applied Biological Science, Tokyo University of Science, Tokyo, Japan
| | - Masako Yamasaki
- Department of Virology II, National Institute of Infectious Diseases, Tokyo, Japan.,Department of Applied Biological Science, Tokyo University of Science, Tokyo, Japan
| | - Shoya Iwanami
- Interdisciplinary Biology Laboratory (iBLab), Division of Biological Science, Graduate School of Science, Nagoya University, Nagoya, Japan.,Department of Biology, Faculty of Sciences, Kyushu University, Fukuoka, Japan
| | - Yusuke Ito
- Department of Biology, Faculty of Sciences, Kyushu University, Fukuoka, Japan
| | - Shuetsu Fukushi
- Department of Virology I, National Institute of Infectious Diseases, Tokyo, Japan
| | - Hirofumi Ohashi
- Department of Virology II, National Institute of Infectious Diseases, Tokyo, Japan.,Department of Applied Biological Science, Tokyo University of Science, Tokyo, Japan
| | - Wakana Saso
- Department of Virology II, National Institute of Infectious Diseases, Tokyo, Japan.,The Institute of Medical Science, The University of Tokyo, Tokyo, Japan.,AIDS Research Center, National Institute of Infectious Diseases, Tokyo, Japan
| | - Tomohiro Tanaka
- Faculty of Pharmaceutical Sciences, Tokyo University of Science, Tokyo, Japan
| | - Shin Aoki
- Research Institute for Science and Technology, Tokyo University of Science, Tokyo, Japan
| | - Kouji Kuramochi
- Department of Applied Biological Science, Tokyo University of Science, Tokyo, Japan
| | - Shingo Iwami
- Interdisciplinary Biology Laboratory (iBLab), Division of Biological Science, Graduate School of Science, Nagoya University, Nagoya, Japan.,Department of Biology, Faculty of Sciences, Kyushu University, Fukuoka, Japan.,MIRAI, JST, Saitama, Japan.,Institute of Mathematics for Industry, Kyushu University, Fukuoka, Japan.,Institute for the Advanced Study of Human Biology (ASHBi), Kyoto University, Kyoto, Japan.,NEXT-Ganken Program, Japanese Foundation for Cancer Research (JFCR), Tokyo, Japan.,Science Groove Inc., Fukuoka, Japan
| | - Yoshimasa Takahashi
- Department of Immunology, National Institute of Infectious Diseases, Tokyo, Japan.,Research Center for Drug and Vaccine Development, National Institute of Infectious Diseases, Tokyo, Japan
| | - Tadaki Suzuki
- Department of Pathology, National Institute of Infectious Diseases, Tokyo, Japan
| | - Masamichi Muramatsu
- Department of Virology II, National Institute of Infectious Diseases, Tokyo, Japan
| | - Makoto Takeda
- Department of Virology III, National Institute of Infectious Diseases, Tokyo, Japan
| | - Takaji Wakita
- Department of Virology II, National Institute of Infectious Diseases, Tokyo, Japan
| | - Koichi Watashi
- Department of Virology II, National Institute of Infectious Diseases, Tokyo, Japan.,Department of Applied Biological Science, Tokyo University of Science, Tokyo, Japan.,MIRAI, JST, Saitama, Japan.,Research Center for Drug and Vaccine Development, National Institute of Infectious Diseases, Tokyo, Japan.,Institute for Frontier Life and Medical Sciences, Kyoto University, Kyoto, Japan
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6
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Gendrot M, Duflot I, Boxberger M, Delandre O, Jardot P, Le Bideau M, Andreani J, Fonta I, Mosnier J, Rolland C, Hutter S, La Scola B, Pradines B. Antimalarial artemisinin-based combination therapies (ACT) and COVID-19 in Africa: In vitro inhibition of SARS-CoV-2 replication by mefloquine-artesunate. Int J Infect Dis 2020; 99:437-440. [PMID: 32805422 PMCID: PMC7426697 DOI: 10.1016/j.ijid.2020.08.032] [Citation(s) in RCA: 66] [Impact Index Per Article: 16.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2020] [Revised: 08/05/2020] [Accepted: 08/10/2020] [Indexed: 12/12/2022] Open
Abstract
OBJECTIVES At the end of November 2019, a novel coronavirus responsible for respiratory tract infections (COVID-19) emerged in China. Despite drastic containment measures, this virus, known as severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), spread in Asia and Europe. The pandemic is ongoing with a particular hotspot in Southern Europe and America; many studies predicted a similar epidemic in Africa, as is currently seen in Europe and the United States of America. However, reported data have not confirmed these predictions. One of the hypotheses that could explain the later emergence and spread of COVID-19 pandemic in African countries is the use of antimalarial drugs to treat malaria, and specifically, artemisinin-based combination therapy (ACT). METHODS The antiviral activity of fixed concentrations of ACT at concentrations consistent with those observed in human plasma when ACT is administered at oral doses for uncomplicated malaria treatment was evaluatedin vitro against a clinically isolated SARS-CoV-2 strain (IHUMI-3) in Vero E6 cells. RESULTS Mefloquine-artesunate exerted the highest antiviral activity with % inhibition of 72.1 ± 18.3 % at expected maximum blood concentration (Cmax) for each ACT drug at doses commonly administered in malaria treatment. All the other combinations, artesunate-amodiaquine, artemether-lumefantrine, artesunate-pyronaridine, or dihydroartemisinin-piperaquine, showed antiviral inhibition in the same ranges (27.1 to 34.1 %). CONCLUSIONS Antimalarial drugs for which concentration data in the lungs are available are concentrated from 10 to 160 fold more in the lungs than in blood. Thesein vitro results reinforce the hypothesis that antimalarial drugs could be effective as an anti-COVID-19 treatment.
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Affiliation(s)
- Mathieu Gendrot
- Unité Parasitologie et Entomologie, Département Microbiologie et Maladies Infectieuses, Institut de Recherche Biomédicale des Armées, Marseille, France; Aix Marseille Univ, IRD, SSA, AP-HM, VITROME, Marseille, France; IHU Méditerranée Infection, Marseille, France
| | - Isabelle Duflot
- IHU Méditerranée Infection, Marseille, France; Aix Marseille Univ, IRD, AP-HM, MEPHI, Marseille, France
| | - Manon Boxberger
- IHU Méditerranée Infection, Marseille, France; Aix Marseille Univ, IRD, AP-HM, MEPHI, Marseille, France
| | - Océane Delandre
- Unité Parasitologie et Entomologie, Département Microbiologie et Maladies Infectieuses, Institut de Recherche Biomédicale des Armées, Marseille, France; Aix Marseille Univ, IRD, SSA, AP-HM, VITROME, Marseille, France; IHU Méditerranée Infection, Marseille, France
| | - Priscilla Jardot
- IHU Méditerranée Infection, Marseille, France; Aix Marseille Univ, IRD, AP-HM, MEPHI, Marseille, France
| | - Marion Le Bideau
- IHU Méditerranée Infection, Marseille, France; Aix Marseille Univ, IRD, AP-HM, MEPHI, Marseille, France
| | - Julien Andreani
- IHU Méditerranée Infection, Marseille, France; Aix Marseille Univ, IRD, AP-HM, MEPHI, Marseille, France
| | - Isabelle Fonta
- Unité Parasitologie et Entomologie, Département Microbiologie et Maladies Infectieuses, Institut de Recherche Biomédicale des Armées, Marseille, France; Aix Marseille Univ, IRD, SSA, AP-HM, VITROME, Marseille, France; IHU Méditerranée Infection, Marseille, France; Centre National de Référence du Paludisme, Marseille, France
| | - Joel Mosnier
- Unité Parasitologie et Entomologie, Département Microbiologie et Maladies Infectieuses, Institut de Recherche Biomédicale des Armées, Marseille, France; Aix Marseille Univ, IRD, SSA, AP-HM, VITROME, Marseille, France; IHU Méditerranée Infection, Marseille, France; Centre National de Référence du Paludisme, Marseille, France
| | - Clara Rolland
- IHU Méditerranée Infection, Marseille, France; Aix Marseille Univ, IRD, AP-HM, MEPHI, Marseille, France
| | - Sébastien Hutter
- Aix Marseille Univ, IRD, SSA, AP-HM, VITROME, Marseille, France; IHU Méditerranée Infection, Marseille, France
| | - Bernard La Scola
- IHU Méditerranée Infection, Marseille, France; Aix Marseille Univ, IRD, AP-HM, MEPHI, Marseille, France
| | - Bruno Pradines
- Unité Parasitologie et Entomologie, Département Microbiologie et Maladies Infectieuses, Institut de Recherche Biomédicale des Armées, Marseille, France; Aix Marseille Univ, IRD, SSA, AP-HM, VITROME, Marseille, France; IHU Méditerranée Infection, Marseille, France; Centre National de Référence du Paludisme, Marseille, France.
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Ong WY, Go ML, Wang DY, Cheah IKM, Halliwell B. Effects of Antimalarial Drugs on Neuroinflammation-Potential Use for Treatment of COVID-19-Related Neurologic Complications. Mol Neurobiol 2020; 58:106-117. [PMID: 32897518 PMCID: PMC7477069 DOI: 10.1007/s12035-020-02093-z] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2020] [Accepted: 08/25/2020] [Indexed: 02/06/2023]
Abstract
The SARS-CoV-2 virus that is the cause of coronavirus disease 2019 (COVID-19) affects not only peripheral organs such as the lungs and blood vessels, but also the central nervous system (CNS)—as seen by effects on smell, taste, seizures, stroke, neuropathological findings and possibly, loss of control of respiration resulting in silent hypoxemia. COVID-19 induces an inflammatory response and, in severe cases, a cytokine storm that can damage the CNS. Antimalarials have unique properties that distinguish them from other anti-inflammatory drugs. (A) They are very lipophilic, which enhances their ability to cross the blood-brain barrier (BBB). Hence, they have the potential to act not only in the periphery but also in the CNS, and could be a useful addition to our limited armamentarium against the SARS-CoV-2 virus. (B) They are non-selective inhibitors of phospholipase A2 isoforms, including cytosolic phospholipase A2 (cPLA2). The latter is not only activated by cytokines but itself generates arachidonic acid, which is metabolized by cyclooxygenase (COX) to pro-inflammatory eicosanoids. Free radicals are produced in this process, which can lead to oxidative damage to the CNS. There are at least 4 ways that antimalarials could be useful in combating COVID-19. (1) They inhibit PLA2. (2) They are basic molecules capable of affecting the pH of lysosomes and inhibiting the activity of lysosomal enzymes. (3) They may affect the expression and Fe2+/H+ symporter activity of iron transporters such as divalent metal transporter 1 (DMT1), hence reducing iron accumulation in tissues and iron-catalysed free radical formation. (4) They could affect viral replication. The latter may be related to their effect on inhibition of PLA2 isoforms. Inhibition of cPLA2 impairs an early step of coronavirus replication in cell culture. In addition, a secretory PLA2 (sPLA2) isoform, PLA2G2D, has been shown to be essential for the lethality of SARS-CoV in mice. It is important to take note of what ongoing clinical trials on chloroquine and hydroxychloroquine can eventually tell us about the use of antimalarials and other anti-inflammatory agents, not only for the treatment of COVID-19, but also for neurovascular disorders such as stroke and vascular dementia.
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Affiliation(s)
- Wei-Yi Ong
- Department of Anatomy, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, 119260, Singapore.
- Neurobiology Programme, Life Sciences Institute, National University of Singapore, Singapore, 119260, Singapore.
| | - Mei-Lin Go
- Department of Pharmacy, Faculty of Science, National University of Singapore, Singapore, 119260, Singapore
| | - De-Yun Wang
- Department of Otolaryngology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, 119260, Singapore
| | - Irwin Kee-Mun Cheah
- Neurobiology Programme, Life Sciences Institute, National University of Singapore, Singapore, 119260, Singapore
- Department of Biochemistry, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, 119260, Singapore
| | - Barry Halliwell
- Neurobiology Programme, Life Sciences Institute, National University of Singapore, Singapore, 119260, Singapore.
- Department of Biochemistry, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, 119260, Singapore.
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8
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Gendrot M, Andreani J, Boxberger M, Jardot P, Fonta I, Le Bideau M, Duflot I, Mosnier J, Rolland C, Bogreau H, Hutter S, La Scola B, Pradines B. Antimalarial drugs inhibit the replication of SARS-CoV-2: An in vitro evaluation. Travel Med Infect Dis 2020; 37:101873. [PMID: 32916297 PMCID: PMC7477610 DOI: 10.1016/j.tmaid.2020.101873] [Citation(s) in RCA: 61] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2020] [Revised: 08/31/2020] [Accepted: 09/01/2020] [Indexed: 12/12/2022]
Abstract
In December 2019, a new severe acute respiratory syndrome coronavirus (SARS-CoV-2) causing coronavirus diseases 2019 (COVID-19) emerged in Wuhan, China. African countries see slower dynamic of COVID-19 cases and deaths. One of the assumptions that may explain this later emergence in Africa, and more particularly in malaria endemic areas, would be the use of antimalarial drugs. We investigated the in vitro antiviral activity against SARS-CoV-2 of several antimalarial drugs. Chloroquine (EC50 = 2.1 μM and EC90 = 3.8 μM), hydroxychloroquine (EC50 = 1.5 μM and EC90 = 3.0 μM), ferroquine (EC50 = 1.5 μM and EC90 = 2.4 μM), desethylamodiaquine (EC50 = 0.52 μM and EC90 = 1.9 μM), mefloquine (EC50 = 1.8 μM and EC90 = 8.1 μM), pyronaridine (EC50 = 0.72 μM and EC90 = 0.75 μM) and quinine (EC50 = 10.7 μM and EC90 = 38.8 μM) showed in vitro antiviral effective activity with IC50 and IC90 compatible with drug oral uptake at doses commonly administered in malaria treatment. The ratio Clung/EC90 ranged from 5 to 59. Lumefantrine, piperaquine and dihydroartemisinin had IC50 and IC90 too high to be compatible with expected plasma concentrations (ratio Cmax/EC90 < 0.05). Based on our results, we would expect that countries which commonly use artesunate-amodiaquine or artesunate-mefloquine report fewer cases and deaths than those using artemether-lumefantrine or dihydroartemisinin-piperaquine. It could be necessary now to compare the antimalarial use and the dynamics of COVID-19 country by country to confirm this hypothesis.
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Affiliation(s)
- Mathieu Gendrot
- Unité Parasitologie et Entomologie, Département Microbiologie et Maladies Infectieuses, Institut de Recherche Biomédicale des Armées, Marseille, France; Aix Marseille Univ, IRD, SSA, AP-HM, VITROME, Marseille, France; IHU Méditerranée Infection, Marseille, France
| | - Julien Andreani
- IHU Méditerranée Infection, Marseille, France; Aix Marseille Univ, IRD, AP-HM, MEPHI, Marseille, France
| | - Manon Boxberger
- IHU Méditerranée Infection, Marseille, France; Aix Marseille Univ, IRD, AP-HM, MEPHI, Marseille, France
| | - Priscilla Jardot
- IHU Méditerranée Infection, Marseille, France; Aix Marseille Univ, IRD, AP-HM, MEPHI, Marseille, France
| | - Isabelle Fonta
- Unité Parasitologie et Entomologie, Département Microbiologie et Maladies Infectieuses, Institut de Recherche Biomédicale des Armées, Marseille, France; Aix Marseille Univ, IRD, SSA, AP-HM, VITROME, Marseille, France; IHU Méditerranée Infection, Marseille, France; Centre National de Référence Du Paludisme, Marseille, France
| | - Marion Le Bideau
- IHU Méditerranée Infection, Marseille, France; Aix Marseille Univ, IRD, AP-HM, MEPHI, Marseille, France
| | - Isabelle Duflot
- IHU Méditerranée Infection, Marseille, France; Aix Marseille Univ, IRD, AP-HM, MEPHI, Marseille, France
| | - Joel Mosnier
- Unité Parasitologie et Entomologie, Département Microbiologie et Maladies Infectieuses, Institut de Recherche Biomédicale des Armées, Marseille, France; Aix Marseille Univ, IRD, SSA, AP-HM, VITROME, Marseille, France; IHU Méditerranée Infection, Marseille, France; Centre National de Référence Du Paludisme, Marseille, France
| | - Clara Rolland
- IHU Méditerranée Infection, Marseille, France; Aix Marseille Univ, IRD, AP-HM, MEPHI, Marseille, France
| | - Hervé Bogreau
- Unité Parasitologie et Entomologie, Département Microbiologie et Maladies Infectieuses, Institut de Recherche Biomédicale des Armées, Marseille, France; Aix Marseille Univ, IRD, SSA, AP-HM, VITROME, Marseille, France; IHU Méditerranée Infection, Marseille, France; Centre National de Référence Du Paludisme, Marseille, France
| | - Sébastien Hutter
- Aix Marseille Univ, IRD, SSA, AP-HM, VITROME, Marseille, France; IHU Méditerranée Infection, Marseille, France
| | - Bernard La Scola
- IHU Méditerranée Infection, Marseille, France; Aix Marseille Univ, IRD, AP-HM, MEPHI, Marseille, France.
| | - Bruno Pradines
- Unité Parasitologie et Entomologie, Département Microbiologie et Maladies Infectieuses, Institut de Recherche Biomédicale des Armées, Marseille, France; Aix Marseille Univ, IRD, SSA, AP-HM, VITROME, Marseille, France; IHU Méditerranée Infection, Marseille, France; Centre National de Référence Du Paludisme, Marseille, France.
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9
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Duparc S, Chalon S, Miller S, Richardson N, Toovey S. Neurological and psychiatric safety of tafenoquine in Plasmodium vivax relapse prevention: a review. Malar J 2020; 19:111. [PMID: 32169086 PMCID: PMC7071640 DOI: 10.1186/s12936-020-03184-x] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2019] [Accepted: 03/06/2020] [Indexed: 12/20/2022] Open
Abstract
BACKGROUND Tafenoquine is an 8-aminoquinoline anti-malarial drug recently approved as a single-dose (300 mg) therapy for Plasmodium vivax relapse prevention, when co-administered with 3-days of chloroquine or other blood schizonticide. Tafenoquine 200 mg weekly after a loading dose is also approved as travellers' prophylaxis. The development of tafenoquine has been conducted over many years, using various dosing regimens in diverse populations. METHODS This review brings together all the preclinical and clinical data concerning tafenoquine central nervous system safety. Data were assembled from published sources. The risk of neuropsychiatric adverse events (NPAEs) with single-dose tafenoquine (300 mg) in combination with chloroquine to achieve P. vivax relapse prevention is particularly examined. RESULTS There was no evidence of neurotoxicity with tafenoquine in preclinical animal models. In clinical studies in P. vivax relapse prevention, nervous system adverse events, mainly headache and dizziness, occurred in 11.4% (36/317) of patients with tafenoquine (300 mg)/chloroquine versus 10.2% (19/187) with placebo/chloroquine; and in 15.5% (75/483) of patients with tafenoquine/chloroquine versus 13.3% (35/264) with primaquine (15 mg/day for 14 days)/chloroquine. Psychiatric adverse events, mainly insomnia, occurred in 3.8% (12/317) of patients with tafenoquine/chloroquine versus 2.7% (5/187) with placebo/chloroquine; and in 2.9% (14/483) of patients with tafenoquine/chloroquine versus 3.4% (9/264) for primaquine/chloroquine. There were no serious or severe NPAEs observed with tafenoquine (300 mg)/chloroquine in these studies. CONCLUSIONS The risk:benefit of single-dose tafenoquine/chloroquine in P. vivax relapse prevention is favourable in the presence of malaria, with a low risk of NPAEs, similar to that seen with chloroquine alone or primaquine/chloroquine.
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Affiliation(s)
- Stephan Duparc
- Medicines for Malaria Venture, Route de Pré-Bois 20, 1215, Geneva 15, Switzerland.
| | - Stephan Chalon
- Medicines for Malaria Venture, Route de Pré-Bois 20, 1215, Geneva 15, Switzerland
| | | | | | - Stephen Toovey
- Medicines for Malaria Venture, Route de Pré-Bois 20, 1215, Geneva 15, Switzerland.,Pegasus Research, London, UK
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10
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McCarthy S. Malaria Prevention, Mefloquine Neurotoxicity, Neuropsychiatric Illness, and Risk-Benefit Analysis in the Australian Defence Force. J Parasitol Res 2015; 2015:287651. [PMID: 26793391 PMCID: PMC4697095 DOI: 10.1155/2015/287651] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2015] [Accepted: 09/13/2015] [Indexed: 11/17/2022] Open
Abstract
The Australian Defence Force (ADF) has used mefloquine for malaria chemoprophylaxis since 1990. Mefloquine has been found to be a plausible cause of a chronic central nervous system toxicity syndrome and a confounding factor in the diagnosis of existing neuropsychiatric illnesses prevalent in the ADF such as posttraumatic stress disorder and traumatic brain injury. Overall health risks appear to have been mitigated by restricting the drug's use; however serious risks were realised when significant numbers of ADF personnel were subjected to clinical trials involving the drug. The full extent of the exposure, health impacts for affected individuals, and consequences for ADF health management including mental health are not yet known, but mefloquine may have caused or aggravated neuropsychiatric illness in large numbers of patients who were subsequently misdiagnosed and mistreated or otherwise failed to receive proper care. Findings in relation to chronic mefloquine neurotoxicity were foreseeable, but this eventuality appears not to have been considered during risk-benefit analyses. Thorough analysis by the ADF would have identified this long-term risk as well as other qualitative risk factors. Historical exposure of ADF personnel to mefloquine neurotoxicity now also necessitates ongoing risk monitoring and management in the overall context of broader health policies.
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Affiliation(s)
- Stuart McCarthy
- Headquarters 2nd Division, Australian Army, Randwick Barracks, Randwick, NSW 2031, Australia
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11
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Quinn JC. Complex Membrane Channel Blockade: A Unifying Hypothesis for the Prodromal and Acute Neuropsychiatric Sequelae Resulting from Exposure to the Antimalarial Drug Mefloquine. J Parasitol Res 2015; 2015:368064. [PMID: 26576290 PMCID: PMC4630403 DOI: 10.1155/2015/368064] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2015] [Accepted: 09/28/2015] [Indexed: 12/18/2022] Open
Abstract
The alkaloid toxin quinine and its derivative compounds have been used for many centuries as effective medications for the prevention and treatment of malaria. More recently, synthetic derivatives, such as the quinoline derivative mefloquine (bis(trifluoromethyl)-(2-piperidyl)-4-quinolinemethanol), have been widely used to combat disease caused by chloroquine-resistant strains of the malaria parasite, Plasmodium falciparum. However, the parent compound quinine, as well as its more recent counterparts, suffers from an incidence of adverse neuropsychiatric side effects ranging from mild mood disturbances and anxiety to hallucinations, seizures, and psychosis. This review considers how the pharmacology, cellular neurobiology, and membrane channel kinetics of mefloquine could lead to the significant and sometimes life-threatening neurotoxicity associated with mefloquine exposure. A key role for mefloquine blockade of ATP-sensitive potassium channels and connexins in the substantia nigra is considered as a unifying hypothesis for the pathogenesis of severe neuropsychiatric events after mefloquine exposure in humans.
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Affiliation(s)
- Jane C. Quinn
- Plant and Animal Toxicology Group, School of Animal and Veterinary Sciences, Graham Centre for Agricultural Innovation, Charles Sturt University, Boorooma Street, Wagga Wagga, NSW 2650, Australia
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12
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Sano Y, Nakano Y, Omoto M, Takao M, Ikeda E, Oga A, Nakamichi K, Saijo M, Maoka T, Sano H, Kawai M, Kanda T. Rituximab-associated progressive multifocal leukoencephalopathy derived from non-Hodgkin lymphoma: neuropathological findings and results of mefloquine treatment. Intern Med 2015; 54:965-70. [PMID: 25876582 DOI: 10.2169/internalmedicine.54.2308] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
A 66-year-old man with non-Hodgkin lymphoma (NHL) developed progressive multifocal leukoencephalopathy (PML) after undergoing chemotherapy including rituximab. Although the administration of mefloquine at a dose of 500 mg weekly temporarily led to a dramatic decrease in the copy number of JC Virus DNA in the cerebrospinal fluid, the patient's symptoms gradually worsened. The CD4(+) T count remained continuously low, at least until approximately five months after the last cycle of chemotherapy. A postmortem examination performed 10 months after the onset of PML disclosed a severe condition associated with rituximab-treated PML originating from NHL and a high mefloquine concentration in the brain. The accumulation of further data regarding mefloquine treatment in PML cases may help to elucidate the optimal dosage and time window for effectively treating PML.
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Affiliation(s)
- Yasuteru Sano
- Department of Neurology and Clinical Neuroscience, Yamaguchi University Graduate School of Medicine, Japan
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13
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Janowsky A, Eshleman AJ, Johnson RA, Wolfrum KM, Hinrichs DJ, Yang J, Zabriskie TM, Smilkstein MJ, Riscoe MK. Mefloquine and psychotomimetics share neurotransmitter receptor and transporter interactions in vitro. Psychopharmacology (Berl) 2014; 231:2771-83. [PMID: 24488404 PMCID: PMC4097020 DOI: 10.1007/s00213-014-3446-0] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/15/2013] [Accepted: 01/07/2014] [Indexed: 11/25/2022]
Abstract
RATIONALE Mefloquine is used for the prevention and treatment of chloroquine-resistant malaria, but its use is associated with nightmares, hallucinations, and exacerbation of symptoms of post-traumatic stress disorder. We hypothesized that potential mechanisms of action for the adverse psychotropic effects of mefloquine resemble those of other known psychotomimetics. OBJECTIVES Using in vitro radioligand binding and functional assays, we examined the interaction of (+)- and (-)-mefloquine enantiomers, the non-psychotomimetic anti-malarial agent, chloroquine, and several hallucinogens and psychostimulants with recombinant human neurotransmitter receptors and transporters. RESULTS Hallucinogens and mefloquine bound stereoselectively and with relatively high affinity (K i = 0.71-341 nM) to serotonin (5-HT) 2A but not 5-HT1A or 5-HT2C receptors. Mefloquine but not chloroquine was a partial 5-HT2A agonist and a full 5-HT2C agonist, stimulating inositol phosphate accumulation, with similar potency and efficacy as the hallucinogen dimethyltryptamine (DMT). 5-HT receptor antagonists blocked mefloquine's effects. Mefloquine had low or no affinity for dopamine D1, D2, D3, and D4.4 receptors, or dopamine and norepinephrine transporters. However, mefloquine was a very low potency antagonist at the D3 receptor and mefloquine but not chloroquine or hallucinogens blocked [(3)H]5-HT uptake by the 5-HT transporter. CONCLUSIONS Mefloquine, but not chloroquine, shares an in vitro receptor interaction profile with some hallucinogens and this neurochemistry may be relevant to the adverse neuropsychiatric effects associated with mefloquine use by a small percentage of patients. Additionally, evaluating interactions with this panel of receptors and transporters may be useful for characterizing effects of other psychotropic drugs and for avoiding psychotomimetic effects for new pharmacotherapies, including antimalarial quinolines.
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Affiliation(s)
- Aaron Janowsky
- Research Service (R&D22), VA Medical Center, 3710 SW US Veterans Hospital Road, Portland, OR, 97239, USA,
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Nevin RL. Idiosyncratic quinoline central nervous system toxicity: Historical insights into the chronic neurological sequelae of mefloquine. INTERNATIONAL JOURNAL FOR PARASITOLOGY-DRUGS AND DRUG RESISTANCE 2014; 4:118-25. [PMID: 25057461 PMCID: PMC4095041 DOI: 10.1016/j.ijpddr.2014.03.002] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/03/2014] [Revised: 03/17/2014] [Accepted: 03/19/2014] [Indexed: 12/04/2022]
Abstract
Regulators now warn adverse neurological effects from mefloquine may be irreversible. Many neurological effects resemble those of a common quinoline CNS toxidrome. The quinoline toxidrome is associated with a risk of CNS neuronal degeneration. CNS neuronal degeneration may underlie some neurological effects from mefloquine.
Mefloquine is a quinoline derivative antimalarial which demonstrates promise for the treatment of schistosomiasis. Traditionally employed in prophylaxis and treatment of chloroquine-resistant Plasmodium falciparum malaria, recent changes to the approved European and U.S. product labeling for mefloquine now warn of a risk of permanent and irreversible neurological sequelae including vertigo, loss of balance and symptoms of polyneuropathy. The newly described permanent nature of certain of these neurological effects challenges the conventional belief that they are due merely to the long half-life of mefloquine and its continued presence in the body, and raises new considerations for the rational use of the drug against parasitic disease. In this opinion, it is proposed that many of the reported lasting adverse neurological effects of mefloquine are consistent with the chronic sequelae of a well characterized but idiosyncratic central nervous system (CNS) toxicity syndrome (or toxidrome) common to certain historical antimalarial and antiparasitic quinolines and associated with a risk of permanent neuronal degeneration within specific CNS regions including the brainstem. Issues in the development and licensing of mefloquine are then considered in the context of historical awareness of the idiosyncratic CNS toxicity of related quinoline drugs. It is anticipated that the information presented in this opinion will aid in the future clinical recognition of the mefloquine toxidrome and its chronic sequelae, and in informing improved regulatory evaluation of mefloquine and related quinoline drugs as they are explored for expanded antiparasitic use and for other indications.
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Affiliation(s)
- Remington L Nevin
- Department of Mental Health, Johns Hopkins Bloomberg School of Public Health, 624 N. Broadway, Room 782, Baltimore, MD 21205, United States
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15
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Ramirez J, Mason C, Ali J. Use of mefloquine in multidrug-resistant Mycobacterium avium complex pulmonary disease in an HIV-negative patient. Curr Ther Res Clin Exp 2014; 68:421-9. [PMID: 24692773 DOI: 10.1016/j.curtheres.2007.12.005] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/01/2007] [Indexed: 01/15/2023] Open
Abstract
INTRODUCTION Mycobacterium avium complex (MAC) is a leading cause of pulmonary disease (PD), even in those with intact immunity, representing about 30% of the cases of pleuropulmonary mycobacterial infection. Based on previous studies, macrolides are the only agents used in the treatment of MAC disease for which there is a correlation between in vitro susceptibility and in vivo (clinical) response. However, resistance develops rapidly if single-agent treatment is used. Data regarding treatment of macrolide-resistant MAC (MRMAC) and multidrug-resistant MAC (MDRMAC) are sparse. CASE SUMMARY A 50-year-old, HIV-negative white man, weighing 53.6 kg, with severe chronic obstructive pulmonary disease and bronchiectasis was initially on treatment for MAC-PD and MRMAC. The patient was followed between 1999 and 2006. His treatment history revealed that in addition to the multiple drugs administered during the course of his illness, thalidomide, interferon-γ, and mefloquine were also administered. The patient died ~7 years later due to respiratory failure and overwhelming infection CONCLUSIONS This case report describes the use of mefloquine as adjunct treatment in an HIV-negative patient with MDRMAC-PD and discusses the associated outcomes of drug resistance.
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Affiliation(s)
- Juan Ramirez
- Division of Pulmonary, Critical Care Medicine, Louisiana State University Health Sciences Center, New Orleans, Louisiana
| | - Carol Mason
- Division of Pulmonary, Critical Care Medicine, Louisiana State University Health Sciences Center, New Orleans, Louisiana
| | - Juzar Ali
- Division of Pulmonary, Critical Care Medicine, Louisiana State University Health Sciences Center, New Orleans, Louisiana
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16
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Nakamichi K, Kishida S, Tanaka K, Suganuma A, Sano Y, Sano H, Kanda T, Maeda N, Kira JI, Itoh A, Kato N, Tomimoto H, Kurane I, Lim CK, Mizusawa H, Saijo M. Sequential changes in the non-coding control region sequences of JC polyomaviruses from the cerebrospinal fluid of patients with progressive multifocal leukoencephalopathy. Arch Virol 2012; 158:639-50. [PMID: 23138154 DOI: 10.1007/s00705-012-1532-3] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2012] [Accepted: 10/01/2012] [Indexed: 11/28/2022]
Abstract
Progressive multifocal leukoencephalopathy (PML) is caused by JC polyomavirus (JCV) infection in the brain. JCV isolates from PML patients have variable mutations in the non-coding control region (NCCR) of the genome. This study was conducted to examine sequential changes in NCCR patterns of JCV isolates obtained from the cerebrospinal fluid (CSF) of PML patients. CSF specimens were collected from PML patients at different time points, the NCCR sequences were determined, and their compositions were assessed by computer-based analysis. In patients showing a marked increase in JCV load, the most frequent NCCR sequences in the follow-up specimens were different from those in the initial samples. In contrast, the dominant NCCRs in the CSF remained unaltered during the follow-up of individuals in whom the viral load decreased after therapeutic intervention. These data demonstrate that the majority of JCV variants emerge with the progression of PML and that these changes are suppressed when the viral load is decreased.
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Affiliation(s)
- Kazuo Nakamichi
- Department of Virology 1, National Institute of Infectious Diseases, Toyama, Shinjuku-ku, Tokyo 162-8640, Japan
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17
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Molecular biology, epidemiology, and pathogenesis of progressive multifocal leukoencephalopathy, the JC virus-induced demyelinating disease of the human brain. Clin Microbiol Rev 2012; 25:471-506. [PMID: 22763635 DOI: 10.1128/cmr.05031-11] [Citation(s) in RCA: 285] [Impact Index Per Article: 23.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Progressive multifocal leukoencephalopathy (PML) is a debilitating and frequently fatal central nervous system (CNS) demyelinating disease caused by JC virus (JCV), for which there is currently no effective treatment. Lytic infection of oligodendrocytes in the brain leads to their eventual destruction and progressive demyelination, resulting in multiple foci of lesions in the white matter of the brain. Before the mid-1980s, PML was a relatively rare disease, reported to occur primarily in those with underlying neoplastic conditions affecting immune function and, more rarely, in allograft recipients receiving immunosuppressive drugs. However, with the onset of the AIDS pandemic, the incidence of PML has increased dramatically. Approximately 3 to 5% of HIV-infected individuals will develop PML, which is classified as an AIDS-defining illness. In addition, the recent advent of humanized monoclonal antibody therapy for the treatment of autoimmune inflammatory diseases such as multiple sclerosis (MS) and Crohn's disease has also led to an increased risk of PML as a side effect of immunotherapy. Thus, the study of JCV and the elucidation of the underlying causes of PML are important and active areas of research that may lead to new insights into immune function and host antiviral defense, as well as to potential new therapies.
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Pharmacokinetic considerations in the repositioning of mefloquine for treatment of progressive multifocal leukoencephalopathy. Clin Neurol Neurosurg 2012; 114:1204-5. [DOI: 10.1016/j.clineuro.2012.02.046] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2012] [Accepted: 02/19/2012] [Indexed: 11/23/2022]
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19
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20
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Nevin RL. Limbic encephalopathy and central vestibulopathy caused by mefloquine: a case report. Travel Med Infect Dis 2012; 10:144-51. [PMID: 22494697 DOI: 10.1016/j.tmaid.2012.03.006] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2011] [Revised: 02/21/2012] [Accepted: 03/21/2012] [Indexed: 10/28/2022]
Abstract
Mefloquine is a 4-methanolquinoline anti-malarial that in recent years has fallen out of favor for use as chemoprophylaxis against infection with chloroquine-resistant Plasmodium falciparum malaria owing in part to growing concerns of side effects and potential neurotoxicity. Despite over 20 years of licensed use, the pathophysiological mechanisms underlying mefloquine's neuropsychiatric and physical side effects and the clinical significance of the drug's neurotoxicity have remained poorly understood. In this report, an adverse reaction to mefloquine chemoprophylaxis is described characterized by prodromal symptoms of anxiety with subsequent development of psychosis, short-term memory impairment, confusion and personality change accompanied by complaints of disequilibrium and vertigo, with objective findings of central vestibulopathy. It is posited that these effects represent an idiosyncratic neurotoxic syndrome of progressive limbic encephalopathy and multifocal brainstem injury caused by the drug. This case provides insights into the clinical significance of mefloquine neuronal gap junction blockade and neurotoxicity demonstrated in animal models, points to recommendations for the management of affected patients including diagnostic considerations and appropriate referrals, and highlights critical implications for the continued safe use of the medication.
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Affiliation(s)
- Remington L Nevin
- Department of Preventive Medicine, Bayne-Jones Army Community Hospital, 1585 Third Street, Fort Polk, LA 71459, USA.
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21
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Nevin RL. Investigating channel blockers for the treatment of multiple sclerosis: considerations with mefloquine and carbenoxolone. J Neuroimmunol 2012; 243:106-7. [PMID: 22236373 DOI: 10.1016/j.jneuroim.2011.12.016] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2011] [Accepted: 12/15/2011] [Indexed: 10/14/2022]
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22
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Nevin RL. Mefloquine blockade of connexin 36 and connexin 43 gap junctions and risk of suicide. Biol Psychiatry 2012; 71:e1-2. [PMID: 21861987 DOI: 10.1016/j.biopsych.2011.07.026] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/25/2011] [Accepted: 07/26/2011] [Indexed: 10/17/2022]
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23
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Nevin RL. Mefloquine blockade of connexin 43 (Cx43) and risk of pregnancy loss. Placenta 2011; 32:712. [PMID: 21764445 DOI: 10.1016/j.placenta.2011.06.016] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/22/2011] [Accepted: 06/23/2011] [Indexed: 11/16/2022]
Affiliation(s)
- R L Nevin
- Bayne-Jones Army Community Hospital, Department of Preventive Medicine, 1585 3rd Street, Fort Polk, LA 71459, USA.
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25
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Mo T, Mi X, Milner EE, Dow GS, Wipf P. Synthesis of an 8-pentafluorosulfanyl analog of the antimalarial agent mefloquine. Tetrahedron Lett 2010. [DOI: 10.1016/j.tetlet.2010.07.113] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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26
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Molecular regulation of JC virus tropism: insights into potential therapeutic targets for progressive multifocal leukoencephalopathy. J Neuroimmune Pharmacol 2010; 5:404-17. [PMID: 20401541 DOI: 10.1007/s11481-010-9203-1] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2009] [Accepted: 03/05/2010] [Indexed: 10/19/2022]
Abstract
Progressive multifocal leukoencephalopathy (PML) is a growing concern for patients undergoing immune modulatory therapies for treatment of autoimmune diseases such as multiple sclerosis. Currently, there are no drugs approved for the treatment of PML that have been demonstrated in the patient to effectively and reproducibly alter the course of disease progression. The human polyoma virus JC is the causative agent of PML. JC virus (JCV) dissemination is tightly controlled by regulation of viral gene expression from the promoter by cellular transcription factors expressed in cells permissive for infection. JCV infection likely occurs during childhood, and latent virus containing PML-associated promoter sequences is maintained in lymphoid cells within the bone marrow. Because development of PML is tightly linked to suppression and or modulation of the immune system as in development of hematological malignancies, AIDS, and monoclonal antibody treatments, further scrutiny of the course of JCV infection in immune cells will be essential to our understanding of development of PML and identification of new therapeutic targets.
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Milner E, McCalmont W, Bhonsle J, Caridha D, Carroll D, Gardner S, Gerena L, Gettayacamin M, Lanteri C, Luong T, Melendez V, Moon J, Roncal N, Sousa J, Tungtaeng A, Wipf P, Dow G. Structure–activity relationships amongst 4-position quinoline methanol antimalarials that inhibit the growth of drug sensitive and resistant strains of Plasmodium falciparum. Bioorg Med Chem Lett 2010; 20:1347-51. [DOI: 10.1016/j.bmcl.2010.01.001] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2009] [Revised: 12/29/2009] [Accepted: 01/04/2010] [Indexed: 11/27/2022]
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28
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Wipf P, Mo T, Geib SJ, Caridha D, Dow GS, Gerena L, Roncal N, Milner EE. Synthesis and biological evaluation of the first pentafluorosulfanyl analogs of mefloquine. Org Biomol Chem 2009; 7:4163-5. [PMID: 19795052 PMCID: PMC2929370 DOI: 10.1039/b911483a] [Citation(s) in RCA: 94] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Two novel SF5 analogs of the antimalarial agent mefloquine were synthesized in 5 steps and 10-23% overall yields and found to have improved activity and selectivity against malaria parasites. This work also represents the first report of SF5-substituted quinolines.
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Affiliation(s)
- Peter Wipf
- Department of Chemistry, University of Pittsburgh, Pittsburgh, PA, 15260, USA; Fax: 412-624-0787; Tel: 412-624-8606
- Center for Chemical Methodologies and Library Development, University of Pittsburgh, Pittsburgh, PA, 15260, USA
| | - Tingting Mo
- Department of Chemistry, University of Pittsburgh, Pittsburgh, PA, 15260, USA; Fax: 412-624-0787; Tel: 412-624-8606
- Center for Chemical Methodologies and Library Development, University of Pittsburgh, Pittsburgh, PA, 15260, USA
| | - Steven J. Geib
- Department of Chemistry, University of Pittsburgh, Pittsburgh, PA, 15260, USA; Fax: 412-624-0787; Tel: 412-624-8606
| | - Diana Caridha
- Division of Experimental Therapeutics, Walter Reed Army Institute of Research, 503 Robert Grant Avenue, Silver Spring, MD, 20910, USA; Fax: 301-319-9954; Tel: 301-319-9009
| | - Geoffrey S. Dow
- Division of Experimental Therapeutics, Walter Reed Army Institute of Research, 503 Robert Grant Avenue, Silver Spring, MD, 20910, USA; Fax: 301-319-9954; Tel: 301-319-9009
| | - Lucia Gerena
- Division of Experimental Therapeutics, Walter Reed Army Institute of Research, 503 Robert Grant Avenue, Silver Spring, MD, 20910, USA; Fax: 301-319-9954; Tel: 301-319-9009
| | - Norma Roncal
- Division of Experimental Therapeutics, Walter Reed Army Institute of Research, 503 Robert Grant Avenue, Silver Spring, MD, 20910, USA; Fax: 301-319-9954; Tel: 301-319-9009
| | - Erin E. Milner
- Division of Experimental Therapeutics, Walter Reed Army Institute of Research, 503 Robert Grant Avenue, Silver Spring, MD, 20910, USA; Fax: 301-319-9954; Tel: 301-319-9009
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Epileptogenic potential of mefloquine chemoprophylaxis: a pathogenic hypothesis. Malar J 2009; 8:188. [PMID: 19656408 PMCID: PMC2736201 DOI: 10.1186/1475-2875-8-188] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2009] [Accepted: 08/05/2009] [Indexed: 12/01/2022] Open
Abstract
Background Mefloquine has historically been considered safe and well-tolerated for long-term malaria chemoprophylaxis, but prescribing it requires careful attention in order to rule out contraindications to its use. Contraindications include a history of certain neurological conditions that might increase the risk of seizure and other adverse events. The precise pathophysiological mechanism by which mefloquine might predispose those with such a history to seizure remains unclear. Presentation of the hypothesis Studies have demonstrated that mefloquine at doses consistent with chemoprophylaxis accumulates at high levels in brain tissue, which results in altered neuronal calcium homeostasis, altered gap-junction functioning, and contributes to neuronal cell death. This paper reviews the scientific evidence associating mefloquine with alterations in neuronal function, and it suggests the novel hypothesis that among those with the prevalent EPM1 mutation, inherited and mefloquine-induced impairments in neuronal physiologic safeguards might increase risk of GABAergic seizure during mefloquine chemoprophylaxis. Testing and implications of the hypothesis Consistent with case reports of tonic-clonic seizures occurring during mefloquine chemoprophylaxis among those with family histories of epilepsy, it is proposed here that a new contraindication to mefloquine use be recognized for people with EPM1 mutation and for those with a personal history of myoclonus or ataxia, or a family history of degenerative neurologic disorder consistent with EPM1. Recommendations and directions for future research are presented.
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Identification and characterization of mefloquine efficacy against JC virus in vitro. Antimicrob Agents Chemother 2009; 53:1840-9. [PMID: 19258267 DOI: 10.1128/aac.01614-08] [Citation(s) in RCA: 183] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Progressive multifocal leukoencephalopathy (PML) is a rare but frequently fatal disease caused by the uncontrolled replication of JC virus (JCV), a polyomavirus, in the brains of some immunocompromised individuals. Currently, no effective antiviral treatment for this disease has been identified. As a first step in the identification of such therapy, we screened the Spectrum collection of 2,000 approved drugs and biologically active molecules for their anti-JCV activities in an in vitro infection assay. We identified a number of different drugs and compounds that had significant anti-JCV activities at micromolar concentrations and lacked cellular toxicity. Of the compounds with anti-JCV activities, only mefloquine, an antimalarial agent, has been reported to show sufficiently high penetration into the central nervous system such that it would be predicted to achieve efficacious concentrations in the brain. Additional in vitro experiments demonstrated that mefloquine inhibits the viral infection rates of three different JCV isolates, JCV(Mad1), JCV(Mad4), and JCV(M1/SVEDelta), and does so in three different cell types, transformed human glial (SVG-A) cells, primary human fetal glial cells, and primary human astrocytes. Using quantitative PCR to quantify the number of viral copies in cultured cells, we have also shown that mefloquine inhibits viral DNA replication. Finally, we demonstrated that mefloquine does not block viral cell entry; rather, it inhibits viral replication in cells after viral entry. Although no suitable animal model of PML or JCV infection is available for the testing of mefloquine in vivo, our in vitro results, combined with biodistribution data published in the literature, suggest that mefloquine could be an effective therapy for PML.
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Mefloquine-induced disruption of calcium homeostasis in mammalian cells is similar to that induced by ionomycin. Antimicrob Agents Chemother 2007; 52:684-93. [PMID: 17999964 DOI: 10.1128/aac.00874-07] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
In previous studies, we have shown that mefloquine disrupts calcium homeostasis in neurons by depletion of endoplasmic reticulum (ER) stores, followed by an influx of external calcium across the plasma membrane. In this study, we explore two hypotheses concerning the mechanism(s) of action of mefloquine. First, we investigated the possibility that mefloquine activates non-N-methyl-d-aspartic acid receptors and the inositol phosphate 3 (IP3) signaling cascade leading to ER calcium release. Second, we compared the disruptive effects of mefloquine on calcium homeostasis to those of ionomycin in neuronal and nonneuronal cells. Ionomycin is known to discharge the ER calcium store (through an undefined mechanism), which induces capacitative calcium entry (CCE). In radioligand binding assays, mefloquine showed no affinity for the known binding sites of several glutamate receptor subtypes. The pattern of neuroprotection induced by a panel of glutamate receptor antagonists was dissimilar to that of mefloquine. Both mefloquine and ionomycin exhibited dose-related and qualitatively similar disruptions of calcium homeostasis in both neurons and macrophages. The influx of external calcium was blocked by the inhibitors of CCE in a dose-related fashion. Both mefloquine and ionomycin upregulated the IP3 pathway in a manner that we interpret to be secondary to CCE. Collectively, these data suggest that mefloquine does not activate glutamate receptors and that it disrupts calcium homeostasis in mammalian cells in a manner similar to that of ionomycin.
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Dow GS, Caridha D, Goldberg M, Wolf L, Koenig ML, Yourick DL, Wang Z. Transcriptional profiling of mefloquine-induced disruption of calcium homeostasis in neurons in vitro. Genomics 2005; 86:539-50. [PMID: 16109470 DOI: 10.1016/j.ygeno.2005.07.004] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2005] [Revised: 07/07/2005] [Accepted: 07/14/2005] [Indexed: 11/26/2022]
Abstract
Mefloquine is associated with adverse neurological effects that are mediated via unknown mechanisms. Recent in vitro studies have shown that mefloquine disrupts neuronal calcium homeostasis via liberation of the endoplasmic reticulum (ER) store and induction of calcium influx across the plasma membrane. In the present study, global changes in gene expression induced in neurons in response to mefloquine-induced disruption of calcium homeostasis and appropriate control agents were investigated in vitro using Affymetrix arrays. The mefloquine transcriptome was found to be enriched for important regulatory sequences of the unfolded protein response and the drug was also found to induce key ER stress proteins, albeit in a manner dissimilar to, and at higher equivalent concentrations than, known ER-tropic agents like thapsigargin. Mefloquine also down-regulated several important functional categories of genes, including transcripts encoding G proteins and ion channels. These effects may be related to intrusion of extracellular calcium since they were also observed after glutamate, but not thapsigargin, hydrogen peroxide, or low-dose mefloquine treatment. Mefloquine could be successfully differentiated from other treatments on the basis of principle component analysis of its "calcium-relevant" transcriptome. These data may aid interpretation of expression of results from future in vivo studies.
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Affiliation(s)
- Geoffrey S Dow
- Division of Experimental Therapeutics, Walter Reed Army Institute of Research, 503 Robert Grant Avenue, Silver Spring, MD 20910, USA.
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Dow GS, Koenig ML, Wolf L, Gerena L, Lopez-Sanchez M, Hudson TH, Bhattacharjee AK. The antimalarial potential of 4-quinolinecarbinolamines may be limited due to neurotoxicity and cross-resistance in mefloquine-resistant Plasmodium falciparum strains. Antimicrob Agents Chemother 2004; 48:2624-32. [PMID: 15215119 PMCID: PMC434181 DOI: 10.1128/aac.48.7.2624-2632.2004] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The clinical potential of mefloquine has been compromised by reports of adverse neurological effects. A series of 4-quinolinecarbinolamines were compared in terms of neurotoxicity and antimalarial activity in an attempt to identify replacement drugs. Neurotoxicity (MTT [thiazolyl blue reduction] assay) was assessed by exposure of cultured embryonic rat neurons to graded concentrations of the drugs for 20 min. The 50% inhibitory concentration (IC(50)) of mefloquine was 25 microM, while those of the analogs were 19 to 200 microM. The relative (to mefloquine) therapeutic indices of the analogs were determined after using the tritiated hypoxanthine assay for assessment of the antimalarial activity of the analogs against mefloquine-sensitive (W2) and -resistant (D6 and TM91C235) Plasmodium falciparum strains. Five analogs, WR157801, WR073892, WR007930, WR007333, and WR226253, were less neurotoxic than mefloquine and exhibited higher relative therapeutic indices (RTIs) against TM91C235 (2.9 to 12.2). Conventional quinoline antimalarials were generally less neurotoxic (IC(50)s of 400, 600, and 900 for amodiaquine, chloroquine, and quinine) or had higher RTIs (e.g., 30 for halofantrine against TM91C235). The neurotoxicity data for the 4-quinolinecarbinolamines were used to develop a three-dimensional (3D), function-based pharmacophore. The crucial molecular features correlated with neurotoxicity were a hydrogen bond acceptor (lipid) function, an aliphatic hydrophobic function, and a ring aromatic function specifically distributed in the 3D surface of the molecule. Mapping of the 3D structures of a series of structurally diverse quinolines to the pharmacophore allowed accurate qualitative predictions of neurotoxicity (or not) to be made. Extension of this in silico screening approach may aid in the identification of less-neurotoxic quinoline analogs.
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Affiliation(s)
- Geoffrey S Dow
- Parasitology Department, Division of Experimental Therapeutics, Walter Reed Army Institute of Research, 503 Robert Grant Avenue, Silver Spring, MD 20910, USA.
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Dow GS, Hudson TH, Vahey M, Koenig ML. The acute neurotoxicity of mefloquine may be mediated through a disruption of calcium homeostasis and ER function in vitro. Malar J 2003; 2:14. [PMID: 12848898 PMCID: PMC194860 DOI: 10.1186/1475-2875-2-14] [Citation(s) in RCA: 54] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2003] [Accepted: 06/12/2003] [Indexed: 11/15/2022] Open
Abstract
BACKGROUND There is no established biochemical basis for the neurotoxicity of mefloquine. We investigated the possibility that the acute in vitro neurotoxicity of mefloquine might be mediated through a disruptive effect of the drug on endoplasmic reticulum (ER) calcium homeostasis. METHODS Laser scanning confocal microscopy was employed to monitor real-time changes in basal intracellular calcium concentrations in embryonic rat neurons in response to mefloquine and thapsigargin (a known inhibitor of the ER calcium pump) in the presence and absence of external calcium. Changes in the transcriptional regulation of known ER stress response genes in neurons by mefloquine were investigated using Affymetrix arrays. The MTT assay was employed to measure the acute neurotoxicity of mefloquine and its antagonisation by thapsigargin. RESULTS At physiologically relevant concentrations mefloquine was found to mobilize neuronal ER calcium stores and antagonize the pharmacological action of thapsigargin, a specific inhibitor of the ER calcium pump. Mefloquine also induced a sustained influx of extra-neuronal calcium via an unknown mechanism. The transcription of key ER proteins including GADD153, PERK, GRP78, PDI, GRP94 and calreticulin were up-regulated by mefloquine, suggesting that the drug induced an ER stress response. These effects appear to be related, in terms of dose effect and kinetics of action, to the acute neurotoxicity of the drug in vitro. CONCLUSIONS Mefloquine was found to disrupt neuronal calcium homeostasis and induce an ER stress response at physiologically relevant concentrations, effects that may contribute, at least in part, to the neurotoxicity of the drug in vitro.
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Affiliation(s)
- Geoffrey S Dow
- Division of Experimental Therapeutics, Walter Reed Army Institute of Research, Silver Spring, MD 20910, United States
| | - Thomas H Hudson
- Division of Experimental Therapeutics, Walter Reed Army Institute of Research, Silver Spring, MD 20910, United States
| | - Maryanne Vahey
- Division of Retrovirology, Walter Reed Army Institute of Research, Rockville, MD 20850, United States
| | - Michael L Koenig
- Division of Neuroscience, Walter Reed Army Institute of Research, Silver Spring, MD, 20910, United States
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