1
|
Dossi E, Blauwblomme T, Moulard J, Chever O, Vasile F, Guinard E, Le Bert M, Couillin I, Pallud J, Capelle L, Huberfeld G, Rouach N. Pannexin-1 channels contribute to seizure generation in human epileptic brain tissue and in a mouse model of epilepsy. Sci Transl Med 2019; 10:10/443/eaar3796. [PMID: 29848662 DOI: 10.1126/scitranslmed.aar3796] [Citation(s) in RCA: 76] [Impact Index Per Article: 15.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2017] [Revised: 11/02/2017] [Accepted: 05/10/2018] [Indexed: 01/08/2023]
Abstract
Epilepsies are characterized by recurrent seizures, which disrupt normal brain function. Alterations in neuronal excitability and excitation-inhibition balance have been shown to promote seizure generation, yet molecular determinants of such alterations remain to be identified. Pannexin channels are nonselective, large-pore channels mediating extracellular exchange of neuroactive molecules. Recent data suggest that these channels are activated under pathological conditions and regulate neuronal excitability. However, whether pannexin channels sustain or counteract chronic epilepsy in human patients remains unknown. We studied the impact of pannexin-1 channel activation in postoperative human tissue samples from patients with epilepsy displaying epileptic activity ex vivo. These samples were obtained from surgical resection of epileptogenic zones in patients suffering from lesional or drug-resistant epilepsy. We found that pannexin-1 channel activation promoted seizure generation and maintenance through adenosine triphosphate signaling via purinergic 2 receptors. Pharmacological inhibition of pannexin-1 channels with probenecid or mefloquine-two medications currently used for treating gout and malaria, respectively-blocked ictal discharges in human cortical brain tissue slices. Genetic deletion of pannexin-1 channels in mice had anticonvulsant effects when the mice were exposed to kainic acid, a model of temporal lobe epilepsy. Our data suggest a proepileptic role of pannexin-1 channels in chronic epilepsy in human patients and that pannexin-1 channel inhibition might represent an alternative therapeutic strategy for treating lesional and drug-resistant epilepsies.
Collapse
Affiliation(s)
- Elena Dossi
- Neuroglial Interactions in Cerebral Physiopathology, Center for Interdisciplinary Research in Biology, Collège de France, CNR UMR 7241, INSERM U1050, Labex Memolife, PSL Research University, 75005 Paris, France
| | - Thomas Blauwblomme
- Assistance Publique-Hopitaux de Paris (AP-HP), Department of Pediatric Neurosurgery, Necker Hospital, INSERM U1129, Paris Descartes University, PRES Sorbonne Paris Cité, 75015 Paris, France.,INSERM U1129, Paris Descartes University, PRES Sorbonne Paris Cité, CEA, 75015 Paris, France
| | - Julien Moulard
- Neuroglial Interactions in Cerebral Physiopathology, Center for Interdisciplinary Research in Biology, Collège de France, CNR UMR 7241, INSERM U1050, Labex Memolife, PSL Research University, 75005 Paris, France
| | - Oana Chever
- Neuroglial Interactions in Cerebral Physiopathology, Center for Interdisciplinary Research in Biology, Collège de France, CNR UMR 7241, INSERM U1050, Labex Memolife, PSL Research University, 75005 Paris, France
| | - Flora Vasile
- Neuroglial Interactions in Cerebral Physiopathology, Center for Interdisciplinary Research in Biology, Collège de France, CNR UMR 7241, INSERM U1050, Labex Memolife, PSL Research University, 75005 Paris, France
| | - Eleonore Guinard
- Neuroglial Interactions in Cerebral Physiopathology, Center for Interdisciplinary Research in Biology, Collège de France, CNR UMR 7241, INSERM U1050, Labex Memolife, PSL Research University, 75005 Paris, France.,INSERM U1129, Paris Descartes University, PRES Sorbonne Paris Cité, CEA, 75015 Paris, France
| | - Marc Le Bert
- CNRS UMR7355, Experimental and Molecular Immunology and Neurogenetics, 45067 Orléans, France
| | - Isabelle Couillin
- CNRS UMR7355, Experimental and Molecular Immunology and Neurogenetics, 45067 Orléans, France
| | - Johan Pallud
- Department of Neurosurgery, Sainte-Anne Hospital and IMA-BRAIN, INSERM U894, Paris Descartes University, PRES Sorbonne Paris Cité, 75014 Paris, France
| | - Laurent Capelle
- Department of Neurosurgery, University Pierre and Marie Curie, La Pitié-Salpêtrière Hospital, AP-HP, Sorbonne Universités, 75013 Paris, France
| | - Gilles Huberfeld
- Neuroglial Interactions in Cerebral Physiopathology, Center for Interdisciplinary Research in Biology, Collège de France, CNR UMR 7241, INSERM U1050, Labex Memolife, PSL Research University, 75005 Paris, France.,INSERM U1129, Paris Descartes University, PRES Sorbonne Paris Cité, CEA, 75015 Paris, France.,Department of Neurophysiology, La Pitié-Salpetrière Hospital, Sorbonne Universités, University Pierre and Marie Curie, AP-HP, 75013 Paris, France
| | - Nathalie Rouach
- Neuroglial Interactions in Cerebral Physiopathology, Center for Interdisciplinary Research in Biology, Collège de France, CNR UMR 7241, INSERM U1050, Labex Memolife, PSL Research University, 75005 Paris, France.
| |
Collapse
|
2
|
Livezey J, Oliver T, Cantilena L. Prolonged Neuropsychiatric Symptoms in a Military Service Member Exposed to Mefloquine. DRUG SAFETY - CASE REPORTS 2016; 3:7. [PMID: 27747687 PMCID: PMC5005770 DOI: 10.1007/s40800-016-0030-z] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
A 32-year-old male developed neuropsychiatric symptoms 2 weeks after starting mefloquine 250 mg/week for malaria prophylaxis. He continued to take the medication for the next 4 months. Initial symptoms included vivid dreams and anxiety, as well as balance problems. These symptoms persisted and progressed over the next 4 years to include vertigo, emotional lability, and poor short-term memory, which have greatly affected his personal and professional life. An extensive evaluation revealed objective evidence supporting a central vestibulopathy. These symptoms have been unresponsive to pharmacologic therapy and psychotherapy. A Naranjo assessment score of 6 was obtained for his initial symptoms, indicating a probable adverse drug reaction to mefloquine given the relationship between the clinical picture and drug exposure.
Collapse
Affiliation(s)
- Jeffrey Livezey
- Department of Clinical Pharmacology, Experimental Therapeutics, Walter Reed Army Institute of Research, 503 Robert Grant Ave, Silver Spring, MD, 20910, USA.
| | - Thomas Oliver
- Division of Clinical Pharmacology and Medical Toxicology, Uniformed Services University of the Health Sciences, Bethesda, MD, 20814, USA
| | - Louis Cantilena
- Division of Clinical Pharmacology and Medical Toxicology, Uniformed Services University of the Health Sciences, Bethesda, MD, 20814, USA
| |
Collapse
|
3
|
|
4
|
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.
Collapse
Affiliation(s)
- Stuart McCarthy
- Headquarters 2nd Division, Australian Army, Randwick Barracks, Randwick, NSW 2031, Australia
| |
Collapse
|
5
|
Identification and characterisation of small molecule inhibitors of feline coronavirus replication. Vet Microbiol 2014; 174:438-447. [PMID: 25465182 PMCID: PMC7117153 DOI: 10.1016/j.vetmic.2014.10.030] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2014] [Revised: 10/26/2014] [Accepted: 10/28/2014] [Indexed: 01/30/2023]
Abstract
Chloroquine, mefloquine, and hexamethylene amiloride demonstrated marked inhibition of FIPV viral replication. All three compounds acted at an early stage of viral replication. A cost effective resazurin-based cytopathic effect inhibition assay was developed for screening compounds. These antiviral compounds, warrant further investigation for clinical use in cats with FIP.
Feline infectious peritonitis (FIP), a feline coronavirus (FCoV) induced disease, is almost invariably fatal with median life expectancy measured in days. Current treatment options are, at best, palliative. The objectives of this study were to evaluate a panel of nineteen candidate compounds for antiviral activity against FCoV in vitro to determine viable candidates for therapy. A resazurin-based cytopathic effect inhibition assay, which detects viable cells through their reduction of the substrate resazurin to fluorescent resorufin, was developed for screening compounds for antiviral efficacy against FCoV. Plaque reduction and virus yield reduction assays were performed to confirm antiviral effects of candidate compounds identified during screening, and the possible antiviral mechanisms of action of these compounds were investigated using virucidal suspension assays and CPE inhibition and IFA-based time of addition assays. Three compounds, chloroquine, mefloquine, and hexamethylene amiloride demonstrated marked inhibition of virus induced CPE at low micromolar concentrations. Orthogonal assays confirmed inhibition of CPE was associated with significant reductions in viral replication. Selectivity indices calculated based on in vitro cytotoxicity screening and reductions in extracellular viral titre were 217, 24, and 20 for chloroquine, mefloquine, and hexamethylene amiloride respectively. Preliminary experiments performed to inform the antiviral mechanism of the compounds demonstrated all three acted at an early stage of viral replication. These results suggest that these direct acting antiviral compounds, or their derivatives, warrant further investigation for clinical use in cats with FIP.
Collapse
|
6
|
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.
Collapse
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
| |
Collapse
|
7
|
Munkhjargal T, AbouLaila M, Terkawi MA, Sivakumar T, Ichikawa M, Davaasuren B, Nyamjargal T, Yokoyama N, Igarashi I. Inhibitory effects of pepstatin A and mefloquine on the growth of Babesia parasites. Am J Trop Med Hyg 2012; 87:681-8. [PMID: 22890034 DOI: 10.4269/ajtmh.2012.12-0218] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
We evaluated the inhibitory effects of pepstatin A and mefloquine on the in vitro and in vivo growths of Babesia parasites. The in vitro growth of Babesia bovis, B. bigemina, B. caballi, and B. equi was significantly inhibited (P < 0.05) by micromolar concentrations of pepstatin A (50% inhibitory concentrations = 38.5, 36.5, 17.6, and 18.1 μM, respectively) and mefloquine (50% inhibitory concentrations = 59.7, 56.7, 20.7, and 4 μM, respectively). Furthermore, both reagents either alone at a concentration of 5 mg/kg or in combinations (2.5/2.5 and 5/5 mg/kg) for 10 days significantly inhibited the in vivo growth of B. microti in mice. Mefloquine treatment was highly effective and the combination treatments were less effective than other treatments. Therefore, mefloquine may antagonize the actions of pepstatin A against babesiosis and aspartic proteases may play an important role in the asexual growth cycle of Babesia parasites.
Collapse
Affiliation(s)
- Tserendorj Munkhjargal
- National Research Center for Protozoan Diseases, Obihiro University of Agriculture and Veterinary Medicine, Inada-cho, Obihiro, Hokkaido, Japan.
| | | | | | | | | | | | | | | | | |
Collapse
|
8
|
Rueangweerayut R, Phyo AP, Uthaisin C, Poravuth Y, Binh TQ, Tinto H, Pénali LK, Valecha N, Tien NT, Abdulla S, Borghini-Fuhrer I, Duparc S, Shin CS, Fleckenstein L. Pyronaridine-artesunate versus mefloquine plus artesunate for malaria. N Engl J Med 2012; 366:1298-309. [PMID: 22475593 DOI: 10.1056/nejmoa1007125] [Citation(s) in RCA: 59] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
BACKGROUND Pyronaridine-artesunate is an artemisinin-based combination therapy under evaluation for the treatment of Plasmodium falciparum and P. vivax malaria. METHODS We conducted a phase 3, open-label, multicenter, noninferiority trial that included 1271 patients between 3 and 60 years of age from Asia (81.3%) or Africa (18.7%) with microscopically confirmed, uncomplicated P. falciparum malaria. Patients underwent randomization for treatment with a fixed-dose combination of 180 mg of pyronaridine and 60 mg of artesunate or with 250 mg of mefloquine plus 100 mg of artesunate. Doses were calculated according to body weight and administered once daily for 3 days. RESULTS Pyronaridine-artesunate was noninferior to mefloquine plus artesunate for the primary outcome: adequate clinical and parasitologic response in the per-protocol population on day 28, corrected for reinfection with the use of polymerase-chain-reaction (PCR) genotyping. For this outcome, efficacy in the group receiving pyronaridine-artesunate was 99.2% (743 of 749 patients; 95% confidence interval [CI], 98.3 to 99.7) and that in the group receiving mefloquine plus artesunate was 97.8% (360 of 368 patients; 95% CI, 95.8 to 99.1), with a treatment difference of 1.4 percentage points (95% CI, 0.0 to 3.5; P=0.05). In the intention-to-treat population, efficacy on day 42 in the group receiving pyronaridine-artesunate was 83.1% (705 of 848 patients; 95% CI, 80.4 to 85.6) and that in the group receiving mefloquine plus artesunate was 83.9% (355 of 423 patients; 95% CI, 80.1 to 87.3). In Cambodia, where there were 211 study patients, the median parasite clearance time was prolonged for both treatments: 64 hours versus 16.0 to 38.9 hours in other countries (P<0.001, on the basis of Kaplan-Meier estimates). Kaplan-Meier estimates of the recrudescence rate in the intention-to-treat population in Cambodia until day 42 were higher with pyronaridine-artesunate than with mefloquine plus artesunate (10.2% [95% CI, 5.4 to 18.6] vs. 0%; P=0.04 as calculated with the log-rank test), but similar for the other countries combined (4.7% [95% CI, 3.3 to 6.7] and 2.8% [95% CI, 1.5 to 5.3], respectively; P=0.24). Elevated levels of aminotransferases were observed in those receiving pyronaridine-artesunate. Two patients receiving mefloquine plus artesunate had seizures. CONCLUSIONS Fixed-dose pyronaridine-artesunate was efficacious in the treatment of uncomplicated P. falciparum malaria. In Cambodia, extended parasite clearance times were suggestive of in vivo resistance to artemisinin. (Funded by Shin Poong Pharmaceutical Company and the Medicines for Malaria Venture; ClinicalTrials.gov number, NCT00403260.).
Collapse
|
9
|
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]
|
10
|
Abstract
The flow of international travellers to and from malaria-endemic areas, especially Africa, has increased in recent years. Apart from the very high morbidity and mortality burden imposed on malaria-endemic areas, imported malaria is the main cause of fever possibly causing severe disease and death in travellers coming from tropical and subtropical areas, particularly Sub-Saharan Africa. The importance of behavioural preventive measures (bed nets, repellents, etc.), adequate chemoprophylaxis and, in selected circumstances, stand-by emergency treatment may not be overemphasized. However, no prophylactic regimen may offer complete protection. Expert advice is needed to tailor prophylactic advice according to traveller (age, baseline clinical conditions, etc.) and travel (destination, season, etc.) characteristics in order to reduce malaria risk.
Collapse
|
11
|
Nevin RL. Mefloquine prescriptions in the presence of contraindications: prevalence among US military personnel deployed to Afghanistan, 2007. Pharmacoepidemiol Drug Saf 2010; 19:206-10. [PMID: 19998269 DOI: 10.1002/pds.1879] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
PURPOSE Contraindications to mefloquine use include a history of certain prevalent neuropsychiatric disorders, which are thought to increase the risk of severe adverse events including anxiety, paranoia, depression, hallucinations, psychosis, and possibly suicide. Within the US military, the continued availability and use of mefloquine is subject to administrative policies dating to 2002 that require clinicians to exercise added caution during prescribing. This analysis was performed to quantify the effectiveness of these policies in ensuring health care provider compliance with package insert prescribing guidance. METHODS A previously identified cohort consisting of 11,725 active duty US military personnel, among whom 1127 (9.6%) had contraindications to mefloquine use identified through medical surveillance and pharmaceutical databases, was examined to identify individuals receiving prescriptions for mefloquine in the 45 days prior to a combat deployment in 2007. RESULTS Among the 11,725 cohort members, 4505 (38.4% of the cohort) received a prescription for mefloquine. Among the 1127 cohort members with contraindications, 155 (1.3% of the cohort) were prescribed mefloquine, comprising 13.8% of those with contraindications. CONCLUSIONS Despite the longstanding administrative policies meant to reduce such events, approximately one in seven individuals with neuropsychiatric contraindications received a prescription for mefloquine prior to a recent combat deployment, significantly increasing the risk of subsequent adverse events. Given the prevalence of neuropsychiatric disorders among US military personnel and the continued availability of mefloquine, additional study is recommended to describe and quantify the nature and extent of mefloquine-associated adverse events experienced among this group.
Collapse
Affiliation(s)
- Remington L Nevin
- United States Africa Command, Combined Joint Task Force Horn of Africa, Camp Lemonier, Djibouti.
| |
Collapse
|
12
|
Current awareness: Pharmacoepidemiology and drug safety. Pharmacoepidemiol Drug Saf 2010. [DOI: 10.1002/pds.1849] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
|