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White E, Kennedy T, Ruffell S, Perkins D, Sarris J. Ayahuasca and Dimethyltryptamine Adverse Events and Toxicity Analysis: A Systematic Thematic Review. Int J Toxicol 2024; 43:327-339. [PMID: 38363085 PMCID: PMC11088222 DOI: 10.1177/10915818241230916] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/17/2024]
Abstract
The objective of this paper is to conduct a systematic thematic review of adverse events, safety, and toxicity of traditional ayahuasca plant preparations and its main psychoactive alkaloids (dimethyltryptamine [DMT], harmine, harmaline, and tetrahydroharmine), including discussing clinical considerations (within clinical trials or approved settings). A systematic literature search of preclinical, clinical, epidemiological, and pharmacovigilance data (as well as pertinent reviews and case studies) was conducted for articles using the electronic databases of PubMed and Web of Science (to 6 July 2023) and PsycINFO, ClinicalTrials.gov, and Embase (to 21 September 2022) and included articles in English in peer-reviewed journals. Additionally, reference lists were searched. Due to the breadth of the area covered, we presented the relevant data in a thematic format. Our searches revealed 78 relevant articles. Data showed that ayahuasca or DMT is generally safe; however, some adverse human events have been reported. Animal models using higher doses of ayahuasca have shown abortifacient and teratogenic effects. Isolated harmala alkaloid studies have also revealed evidence of potential toxicity at higher doses, which may increase with co-administration with certain medications. Harmaline revealed the most issues in preclinical models. Nevertheless, animal models involving higher-dose synthetic isolates may not necessarily be able to be extrapolated to human use of therapeutic doses of plant-based extracts. Serious adverse effects are rarely reported within healthy populations, indicating an acceptable safety profile for the traditional use of ayahuasca and DMT in controlled settings. Further randomized, controlled trials with judicious blinding, larger samples, and longer duration are needed.
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Affiliation(s)
- Eleanor White
- Biomedicine Discovery Institute, Department of Physiology, Monash University, Melbourne, VIC, Australia
| | - Tom Kennedy
- The University of Queensland, Brisbane, QLD, Australia
| | - Simon Ruffell
- Psychae Institue, Melbourne, VIC, Australia
- Onaya Science, Iquitos, Peru
| | - Daniel Perkins
- Psychae Institue, Melbourne, VIC, Australia
- School of Population and Global Health, University of Melbourne, Melbourne, VIC, Australia
- School of Social and Political Science, University of Melbourne, Melbourne, VIC, Australia
- Centre for Mental Health, Swinburne University of Technology, Melbourne, VIC, Australia
| | - Jerome Sarris
- Psychae Institue, Melbourne, VIC, Australia
- Centre for Mental Health, Swinburne University of Technology, Melbourne, VIC, Australia
- NICM Health Research Institute, Western Sydney University, Westmead, NSW, Australia
- The Florey Institute of Neuroscience and Mental Health, University of Melbourne, Melbourne, VIC, Australia
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Knuijver T, ter Heine R, Schellekens AFA, Heydari P, Lucas L, Westra S, Belgers M, van Oosteren T, Verkes RJ, Kramers C. The pharmacokinetics and pharmacodynamics of ibogaine in opioid use disorder patients. J Psychopharmacol 2024; 38:481-488. [PMID: 38519421 PMCID: PMC11102648 DOI: 10.1177/02698811241237873] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 03/24/2024]
Abstract
OBJECTIVE Ibogaine is a hallucinogenic drug that may be used to treat opioid use disorder (OUD). The relationships between pharmacokinetics (PKs) of ibogaine and its metabolites and their clinical effects on side effects and opioid withdrawal severity are unknown. We aimed to study these relationships in patients with OUD undergoing detoxification supported by ibogaine. METHODS The study was performed in 14 subjects with OUD. They received a single dose of 10mg/kg ibogaine hydrochloride. Plasma PKs of ibogaine, noribogaine, and noribogaine glucuronide were obtained during 24 h. Cytochrome P450 isoenzyme 2D6 (CYP2D6) genotyping was performed. The PKs were analyzed by means of nonlinear mixed effects modeling and related with corrected QT interval (QTc) prolongation, cerebellar ataxia, and opioid withdrawal severity. RESULTS The PK of ibogaine were highly variable and significantly correlated to CYP2D6 genotype (p < 0.001). The basic clearance of ibogaine (at a CYP2D6 activity score (AS) of 0) was 0.82 L/h. This increased with 30.7 L/h for every point of AS. The relation between ibogaine plasma concentrations and QTc was best described by a sigmoid Emax model. Spearman correlations were significant (p < 0.03) for ibogaine but not noribogaine with QTc (p = 0.109) and cerebellar effects (p = 0.668); neither correlated with the severity of opioid withdrawal symptoms. CONCLUSIONS The clearance of ibogaine is strongly related to CYPD2D6 genotype. Ibogaine cardiac side effects (QTc time) and cerebellar effects are most likely more driven by ibogaine rather than noribogaine. Future studies should aim at exploring lower doses and/or applying individualized dosing based on CYP2D6 genotype.
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Affiliation(s)
- Thomas Knuijver
- IrisZorg, Nijmegen, The Netherlands
- Nijmegen Institute for Scientist-Practitioners in Addiction, Nijmegen, The Netherlands
| | - Rob ter Heine
- Department of Pharmacy, Research Institute for Medical Innovation, Radboudumc, Nijmegen, The Netherlands
| | - Arnt F. A. Schellekens
- Nijmegen Institute for Scientist-Practitioners in Addiction, Nijmegen, The Netherlands
- Department of Psychiatry, Research Institute for Medical Innovation, Radboudumc, Nijmegen, The Netherlands
| | - Paniz Heydari
- Department of Pharmacy and Pharmacology, The Netherlands Cancer Institute, Amsterdam, The Netherlands
| | - Luc Lucas
- Department of Pharmacy and Pharmacology, The Netherlands Cancer Institute, Amsterdam, The Netherlands
| | - Sjoerd Westra
- Department of Cardiology, Research Institute for Medical Innovation, Radboudumc, Nijmegen, The Netherlands
| | - Maarten Belgers
- IrisZorg, Nijmegen, The Netherlands
- Nijmegen Institute for Scientist-Practitioners in Addiction, Nijmegen, The Netherlands
| | | | - Robbert Jan Verkes
- Department of Psychiatry, Research Institute for Medical Innovation, Radboudumc, Nijmegen, The Netherlands
- Pompestichting, Nijmegen, The Netherlands
| | - Cornelis Kramers
- Department of Pharmacy, Research Institute for Medical Innovation, Radboudumc, Nijmegen, The Netherlands
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Cherian K, Shinozuka K, Tabaac BJ, Arenas A, Beutler BD, Evans VD, Fasano C, Muir OS. Psychedelic Therapy: A Primer for Primary Care Clinicians-Ibogaine. Am J Ther 2024; 31:e133-e140. [PMID: 38518270 DOI: 10.1097/mjt.0000000000001723] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/24/2024]
Abstract
BACKGROUND Ibogaine is a plant-derived alkaloid that has been used for thousands of years in rites of passage and spiritual ceremonies in West-Central Africa. In the West, it has primarily been used and studied for its anti-addictive properties and more recently for other neuropsychiatric indications, including post-traumatic stress disorder, depression, anxiety, and traumatic brain injury. AREAS OF UNCERTAINTY Ibogaine requires careful patient screening and monitoring because of significant safety issues. There is potential for cardiotoxicity (prolonged QT interval); without rigorous screening, fatal arrhythmias may occur. However, preliminary research suggests that co-administration of ibogaine with magnesium may mitigate cardiotoxicity. Additionally, ibogaine may have dangerous interactions with opiates, so patients who receive ibogaine treatment for opioid use disorder must withdraw from long-acting opioids. Other potential concerning effects of ibogaine include rare incidences of mania or psychosis. Anticipated transient effects during ibogaine treatment can include ataxia, tremors, and gastrointestinal symptoms. THERAPEUTIC ADVANCES Robust effects after a single treatment with ibogaine have been reported. In open-label and randomized controlled trials (RCTs), ibogaine reduces heroin and opioid cravings by upwards of 50%, up to 24 weeks after the treatment. An observational study of 30 Special Operations Forces veterans with mild traumatic brain injury reported that 86% were in remission from post-traumatic stress disorder, 83% from depression, and 83% from anxiety, one month after a single-dose ibogaine treatment. LIMITATIONS Although there are several observational and open-label studies, there is only a single double-blind, placebo-controlled RCT on ibogaine. More RCTs with large sample sizes must be conducted to support ibogaine's safety and efficacy. CONCLUSIONS Given the promising preliminary findings, ibogaine could potentially fill a much-needed gap in treatments for challenging conditions, including opioid dependence. Ibogaine's remarkable effects in traditionally treatment-resistant, combat-exposed individuals hints at its potential in broader populations with physical and psychological trauma.
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Affiliation(s)
- Kirsten Cherian
- Department of Psychiatry & Behavioral Sciences, Stanford University, Palo Alto, CA
| | - Kenneth Shinozuka
- Centre for Eudaimonia and Human Flourishing, University of Oxford, Oxford, United Kingdom
- Department of Psychiatry, University of Oxford, Oxford, United Kingdom
| | - Burton J Tabaac
- University of Nevada, Reno School of Medicine, Reno, NV
- Department of Neurology, Carson Tahoe Health, Carson City, NV
| | - Alejandro Arenas
- Department of Anesthesiology, University of Washington School of Medicine, Seattle, WA
| | - Bryce D Beutler
- Keck School of Medicine, University of Southern California, Los Angeles, CA
| | - Viviana D Evans
- Department of Psychiatry, Icahn School of Medicine at Mount Sinai, New York, NY
| | | | - Owen S Muir
- Fermata Health, Brooklyn, NY; and
- Acacia Clinics, Sunnyvale, CA
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4
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Cherian KN, Keynan JN, Anker L, Faerman A, Brown RE, Shamma A, Keynan O, Coetzee JP, Batail JM, Phillips A, Bassano NJ, Sahlem GL, Inzunza J, Millar T, Dickinson J, Rolle CE, Keller J, Adamson M, Kratter IH, Williams NR. Magnesium-ibogaine therapy in veterans with traumatic brain injuries. Nat Med 2024; 30:373-381. [PMID: 38182784 PMCID: PMC10878970 DOI: 10.1038/s41591-023-02705-w] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2023] [Accepted: 11/10/2023] [Indexed: 01/07/2024]
Abstract
Traumatic brain injury (TBI) is a leading cause of disability. Sequelae can include functional impairments and psychiatric syndromes such as post-traumatic stress disorder (PTSD), depression and anxiety. Special Operations Forces (SOF) veterans (SOVs) may be at an elevated risk for these complications, leading some to seek underexplored treatment alternatives such as the oneirogen ibogaine, a plant-derived compound known to interact with multiple neurotransmitter systems that has been studied primarily as a treatment for substance use disorders. Ibogaine has been associated with instances of fatal cardiac arrhythmia, but coadministration of magnesium may mitigate this concern. In the present study, we report a prospective observational study of the Magnesium-Ibogaine: the Stanford Traumatic Injury to the CNS protocol (MISTIC), provided together with complementary treatment modalities, in 30 male SOVs with predominantly mild TBI. We assessed changes in the World Health Organization Disability Assessment Schedule from baseline to immediately (primary outcome) and 1 month (secondary outcome) after treatment. Additional secondary outcomes included changes in PTSD (Clinician-Administered PTSD Scale for DSM-5), depression (Montgomery-Åsberg Depression Rating Scale) and anxiety (Hamilton Anxiety Rating Scale). MISTIC resulted in significant improvements in functioning both immediately (Pcorrected < 0.001, Cohen's d = 0.74) and 1 month (Pcorrected < 0.001, d = 2.20) after treatment and in PTSD (Pcorrected < 0.001, d = 2.54), depression (Pcorrected < 0.001, d = 2.80) and anxiety (Pcorrected < 0.001, d = 2.13) at 1 month after treatment. There were no unexpected or serious adverse events. Controlled clinical trials to assess safety and efficacy are needed to validate these initial open-label findings. ClinicalTrials.gov registration: NCT04313712 .
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Affiliation(s)
- Kirsten N Cherian
- Brain Stimulation Lab, Department of Psychiatry & Behavioral Sciences, Stanford School of Medicine, Stanford, CA, USA
| | - Jackob N Keynan
- Brain Stimulation Lab, Department of Psychiatry & Behavioral Sciences, Stanford School of Medicine, Stanford, CA, USA
| | - Lauren Anker
- Brain Stimulation Lab, Department of Psychiatry & Behavioral Sciences, Stanford School of Medicine, Stanford, CA, USA
| | - Afik Faerman
- Brain Stimulation Lab, Department of Psychiatry & Behavioral Sciences, Stanford School of Medicine, Stanford, CA, USA
| | | | - Ahmed Shamma
- Brain Stimulation Lab, Department of Psychiatry & Behavioral Sciences, Stanford School of Medicine, Stanford, CA, USA
| | - Or Keynan
- Brain Stimulation Lab, Department of Psychiatry & Behavioral Sciences, Stanford School of Medicine, Stanford, CA, USA
| | - John P Coetzee
- Brain Stimulation Lab, Department of Psychiatry & Behavioral Sciences, Stanford School of Medicine, Stanford, CA, USA
- Polytrauma Division, Veterans Affairs Palo Alto Health Care System, Palo Alto, CA, USA
| | - Jean-Marie Batail
- Brain Stimulation Lab, Department of Psychiatry & Behavioral Sciences, Stanford School of Medicine, Stanford, CA, USA
| | - Angela Phillips
- Brain Stimulation Lab, Department of Psychiatry & Behavioral Sciences, Stanford School of Medicine, Stanford, CA, USA
| | - Nicholas J Bassano
- Brain Stimulation Lab, Department of Psychiatry & Behavioral Sciences, Stanford School of Medicine, Stanford, CA, USA
| | - Gregory L Sahlem
- Brain Stimulation Lab, Department of Psychiatry & Behavioral Sciences, Stanford School of Medicine, Stanford, CA, USA
| | - Jose Inzunza
- Ambio Life Sciences, Vancouver, British Columbia, Canada
| | - Trevor Millar
- Ambio Life Sciences, Vancouver, British Columbia, Canada
| | | | - C E Rolle
- Brain Stimulation Lab, Department of Psychiatry & Behavioral Sciences, Stanford School of Medicine, Stanford, CA, USA
| | - Jennifer Keller
- Brain Stimulation Lab, Department of Psychiatry & Behavioral Sciences, Stanford School of Medicine, Stanford, CA, USA
| | - Maheen Adamson
- WRIISC-WOMEN & Department of Rehabilitation, Veterans Affairs Palo Alto Health Care System, Palo Alto, CA, USA
- Department of Neurosurgery, Stanford School of Medicine, Stanford, CA, USA
| | - Ian H Kratter
- Brain Stimulation Lab, Department of Psychiatry & Behavioral Sciences, Stanford School of Medicine, Stanford, CA, USA
| | - Nolan R Williams
- Brain Stimulation Lab, Department of Psychiatry & Behavioral Sciences, Stanford School of Medicine, Stanford, CA, USA.
- Department of Radiology, Stanford School of Medicine, Stanford, CA, USA.
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Zhan X, Do LV, Zou L, Zhan RS, Jones M, Nawaz S, Manaye K. Harmaline toxicity on dorsal striatal neurons and its role in tremor. Neurotoxicology 2023; 99:152-161. [PMID: 37838252 DOI: 10.1016/j.neuro.2023.10.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2022] [Revised: 08/28/2023] [Accepted: 10/08/2023] [Indexed: 10/16/2023]
Abstract
Harmaline is one of the β-carboline derivative compounds that is widely distributed in the food chain and human tissues. Harmine, a dehydrogenated form of harmaline, appeared to have a higher concentration in the brain, and appeared to be elevated in essential tremor (ET) and Parkinson's disease. Exogenous harmaline exposure in high concentration has myriad consequences, including inducing tremor, and causing neurodegeneration of Purkinje cells in the cerebellum. Harmaline-induced tremor is an established animal model for human ET, but its underlying mechanism is still controversial. One hypothesis posits that the inferior olive-cerebellum pathway is involved, and CaV3.1 T-type Ca2+ channel is a critical target of action. However, accumulating evidence indicates that tremor can be generated without disturbing T-type channels. This implies that additional neural circuits or molecular targets are involved. Using in vitro slice Ca2+-imaging and patch clamping, we demonstrated that harmaline reduced intracellular Ca2+ and suppressed depolarization-induced spiking activity of medium spiny striatal neurons (MSN), and this effect of harmaline can be partially attenuated by sulpiride (5 µM). In addition, the frequencies of spontaneous excitatory post-synaptic currents (sEPSCs) on MSNs were also significantly attenuated. Furthermore, the induced tremor in C57BL/6 J mice by harmaline injections (i.p. 12.5-18 mg/kg) was also shown to be attenuated by sulpiride (20 mg/kg). This series of experiments suggests that the dorsal striatum is a site of harmaline toxic action and might contribute to tremor generation. The findings also provide evidence that D2 signaling might be a part of the mechanism underlying essential tremor.
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Affiliation(s)
- Xiping Zhan
- Department of Physiology and Biophysics, College of Medicine, Howard University, Washington, DC 20059, USA; Department of Psychiatry and Behavioral Sciences, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA.
| | - Ly V Do
- Department of Physiology and Biophysics, College of Medicine, Howard University, Washington, DC 20059, USA
| | - Li Zou
- Department of Physiology and Biophysics, College of Medicine, Howard University, Washington, DC 20059, USA
| | - Ryan Shu Zhan
- Department of Physiology and Biophysics, College of Medicine, Howard University, Washington, DC 20059, USA
| | - Michael Jones
- Department of Physiology and Biophysics, College of Medicine, Howard University, Washington, DC 20059, USA
| | - Saba Nawaz
- Department of Physiology and Biophysics, College of Medicine, Howard University, Washington, DC 20059, USA
| | - Kebreten Manaye
- Department of Physiology and Biophysics, College of Medicine, Howard University, Washington, DC 20059, USA
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6
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Fernandes-Nascimento MH, Negrão AB, Viana-Ferreira K, Chaves BDR, Wang YP. Three Decades of Research on the Development of Ibogaine Treatment of Substance Use Disorders: A Scientometric Analysis. J Psychoactive Drugs 2023:1-11. [PMID: 37927218 DOI: 10.1080/02791072.2023.2276230] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2023] [Accepted: 10/06/2023] [Indexed: 11/07/2023]
Abstract
Ibogaine is a natural psychoactive drug that has been investigated for its potential role in the treatment of substance use disorders since the mid-1960s. To evaluate the interest in ibogaine's use as a therapeutic agent, we performed a scientometric analysis covering the last three decades (1993-2002, 2003-2012, and 2013-2022). A complementary analysis was performed to select and describe published clinical trials and meta-analyses. A total of 1523 references were found. Linear growth of publications in the first and third decades were identified, and the average number of publications from 1993 to 2002 was lower than that in the other two decades. Researchers from five continents were identified. Globally, academic research centers in the United States and Canada were the most productive. Cocaine, tobacco, morphine, and alcohol prevailed as major keywords in the first two decades and opioids and psychedelics were included in the third decade. A few key authors were the most co-referenced. One preclinical meta-analysis and no meta-analysis in humans were found. Research trends for ibogaine are widespread, growing, and consonant with current attentiveness in drug abuse. Our findings support the pressing need for rigorous clinical research on ibogaine to evaluate its efficacy and safety.
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Affiliation(s)
- Maria Helha Fernandes-Nascimento
- Programa de Pós-Graduação, Fisiopatologia Experimental, Departamento de Patologia, Faculdade Medicina, Universidade de São Paulo, São Paulo, Brazil
| | - André Brooking Negrão
- Instituto Perdizes, Hospital das Clínicas (HCFMUSP), Faculdade Medicina, Universidade de São Paulo, São Paulo, Brazil
| | - Karine Viana-Ferreira
- Programa de Pós-Graduação, Fisiopatologia Experimental, Departamento de Patologia, Faculdade Medicina, Universidade de São Paulo, São Paulo, Brazil
| | | | - Yuan-Pang Wang
- Instituto de Psiquiatria (LIM-23), Hospital das Clínicas (HCFMUSP), Faculdade Medicina, Universidade de São Paulo, São Paulo, Brazil
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7
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Dickinson JE, Inzunza JAD, Perez-Villa L, Millar TG, Pushparaj AP. Case report: Ibogaine reduced severe neuropathic pain associated with a case of brachial plexus nerve root avulsion. FRONTIERS IN PAIN RESEARCH 2023; 4:1256396. [PMID: 37720911 PMCID: PMC10502345 DOI: 10.3389/fpain.2023.1256396] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2023] [Accepted: 08/11/2023] [Indexed: 09/19/2023] Open
Abstract
Brachial plexus nerve root avulsion results from complete separation of the nerve root from the spinal cord and is one of the most challenging types of neuropathic pain, coinciding with motor, sensory and autonomic deficits. The severe pain and typical impossibility of root reattachment often leads to requests for amputation. Ibogaine is an indole alkaloid producing psychoactive effects through reported actions upon multiple neurotransmitter systems, including NMDA, κ- and µ-opioid receptors and σ2 receptor sites, along with stimulation of neurotrophic factors GDNF and BDNF. In this case report we describe a 53-year-old male with two decades of severe intractable pain due to brachial plexus nerve root avulsion from vehicular trauma who was successfully treated with both high dose inpatient and low dose outpatient administrations of ibogaine. Though promising for future study, the adverse effects of high dose ibogaine administrations may limit tolerability of this saturation protocol to the most refractory cases.
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Affiliation(s)
| | | | | | | | - Abhiram P. Pushparaj
- Scientific Advisory, Ambio Life Sciences, Vancouver, BC, Canada
- Consulting Department, +ROI Regulatory Advisory, Toronto, ON, Canada
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8
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Jiang N, Chen L, Li J, Li W, Jiang S. Lethal and Sublethal Toxicity of Beta-Carboline Alkaloids from Peganum harmala (L.) against Aedes albopictus Larvae (Diptera: Culicidae). TOXICS 2023; 11:341. [PMID: 37112568 PMCID: PMC10143510 DOI: 10.3390/toxics11040341] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/03/2023] [Revised: 03/22/2023] [Accepted: 03/29/2023] [Indexed: 06/19/2023]
Abstract
Plant-derived agents are powerful bio-pesticides for the eco-friendly control of mosquito vectors and other blood-sucking arthropods. The larval toxicity of beta-carboline alkaloids against the Asian tiger mosquito, Aedes albopictus (Skuse) (Diptera: Culicidae), was investigated under laboratory conditions. The total alkaloid extracts (TAEs) and beta-carboline alkaloids (harmaline, harmine, harmalol, and harman) from Peganum harmala seeds were isolated and tested in this bioassay. All alkaloids were tested either individually or as binary mixtures, using the co-toxicity coefficient (CTC) and Abbott's formula analysis. The results revealed considerable toxicity of the tested alkaloids against A. albopictus larvae. When all larval instars were exposed to the TAEs at 48 h post-treatment, the mortality of all larval instars varied in a concentration-dependent manner. The second-instar larvae were the most susceptible to different concentrations of TAEs, and the fourth-instar larvae were more tolerant to TAEs than the second-instar larvae. Especially, the third-instar larvae exposed to all alkaloids also showed that all doses resulted in an increased mortality of the third-instar larvae at 48 h post-treatment, and the toxicities of the tested alkaloids in a descending order were TAEs > harmaline > harmine > harmalol, with the LC50 values of 44.54 ± 2.56, 55.51 ± 3.01, 93.67 ± 4.53, and 117.87 ± 5.61 μg/mL at 48 h post-treatment, respectively. In addition, all compounds were also tested individually or in a 1:1 ratio (dose LC25/LC25) as binary mixtures to assess the synergistic toxicity of these binary combinations against the third-instar larvae at 24 and 48 h post-treatment, respectively. The results demonstrated that when tested as a binary mixture, all compounds (especially TAEs, harmaline, and harmine) showed their synergistic effects, exceeding the toxicity of each compound alone. Interestingly, the obtained data further revealed that the TAEs at sublethal doses (LC10 and LC25) could significantly delay the larval development and decrease the pupation and emergence rates of A. albopictus. This phenomenon could be helpful in order to develop more effective control strategies for different notorious vector mosquitoes.
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Affiliation(s)
- Nan Jiang
- Key Laboratory of Environmental Medicine Engineering, Ministry of Education, School of Public Health, Southeast University, Nanjing 210009, China
| | - Li Chen
- School of Biology and Food Engineering, Fuyang Normal University, Fuyang 236037, China
| | - Jinmei Li
- School of Biology and Food Engineering, Fuyang Normal University, Fuyang 236037, China
| | - Wenyong Li
- School of Biology and Food Engineering, Fuyang Normal University, Fuyang 236037, China
| | - Shuanglin Jiang
- School of Biology and Food Engineering, Fuyang Normal University, Fuyang 236037, China
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Straub CJ, Rusali LE, Kremiller KM, Riley AP. What We Have Gained from Ibogaine: α3β4 Nicotinic Acetylcholine Receptor Inhibitors as Treatments for Substance Use Disorders. J Med Chem 2023; 66:107-121. [PMID: 36440853 PMCID: PMC10034762 DOI: 10.1021/acs.jmedchem.2c01562] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
For decades, ibogaine─the main psychoactive alkaloid found in Tabernanthe iboga─has been investigated as a possible treatment for substance use disorders (SUDs) due to its purported ability to interrupt the addictive properties of multiple drugs of abuse. Of the numerous pharmacological actions of ibogaine and its derivatives, the inhibition of α3β4 nicotinic acetylcholine receptors (nAChRs), represents a probable mechanism of action for their apparent anti-addictive activity. In this Perspective, we examine several classes of compounds that have been discovered and developed to target α3β4 nAChRs. Specifically, by focusing on compounds that have proven efficacious in pre-clinical models of drug abuse and have been evaluated clinically, we highlight the promising potential of the α3β4 nAChRs as viable targets to treat a wide array of SUDs. Additionally, we discuss the challenges faced by the existing classes of α3β4 nAChR ligands that must be overcome to develop them into therapeutic treatments.
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Affiliation(s)
- Carolyn J Straub
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Illinois at Chicago, Chicago, Illinois 60612, United States
| | - Lisa E Rusali
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Illinois at Chicago, Chicago, Illinois 60612, United States
| | - Kyle M Kremiller
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Illinois at Chicago, Chicago, Illinois 60612, United States
| | - Andrew P Riley
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Illinois at Chicago, Chicago, Illinois 60612, United States
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Vorobyeva N, Kozlova AA. Three Naturally-Occurring Psychedelics and Their Significance in the Treatment of Mental Health Disorders. Front Pharmacol 2022; 13:927984. [PMID: 35837277 PMCID: PMC9274002 DOI: 10.3389/fphar.2022.927984] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2022] [Accepted: 06/06/2022] [Indexed: 12/20/2022] Open
Abstract
Classical psychedelics represent a family of psychoactive substances with structural similarities to serotonin and affinity for serotonin receptors. A growing number of studies have found that psychedelics can be effective in treating various psychiatric conditions, including post-traumatic stress disorder, major depressive disorder, anxiety, and substance use disorders. Mental health disorders are extremely prevalent in the general population constituting a major problem for the public health. There are a wide variety of interventions for mental health disorders, including pharmacological therapies and psychotherapies, however, treatment resistance still remains a particular challenge in this field, and relapse rates are also quite high. In recent years, psychedelics have become one of the promising new tools for the treatment of mental health disorders. In this review, we will discuss the three classic serotonergic naturally occurring psychedelics, psilocybin, ibogaine, and N, N-dimethyltryptamine, focusing on their pharmacological properties and clinical potential. The purpose of this article is to provide a focused review of the most relevant research into the therapeutic potential of these substances and their possible integration as alternative or adjuvant options to existing pharmacological and psychological therapies.
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Affiliation(s)
- Nataliya Vorobyeva
- Hive Bio Life Sciences Ltd., London, United Kingdom
- *Correspondence: Nataliya Vorobyeva,
| | - Alena A. Kozlova
- Department of Psychiatry and Psychotherapy, University Hospital Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany
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Knuijver T, Schellekens A, Belgers M, Donders R, van Oosteren T, Kramers K, Verkes R. Safety of ibogaine administration in detoxification of opioid-dependent individuals: a descriptive open-label observational study. Addiction 2022; 117:118-128. [PMID: 33620733 PMCID: PMC9292417 DOI: 10.1111/add.15448] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/07/2020] [Revised: 10/15/2020] [Accepted: 02/02/2021] [Indexed: 11/28/2022]
Abstract
BACKGROUND AND AIMS Ibogaine is an indole alkaloid used in rituals of the African Bwiti tribe. It is also used in non-medical settings to treat addiction. However, ibogaine has been linked to several deaths, mainly due to cardiac events called torsades des pointes preceded by QTc prolongation as well as other safety concerns. This study aimed to evaluate the cardiac, cerebellar and psychomimetic safety of ibogaine in patients with opioid use disorder. DESIGN A descriptive open-label observational study. SETTING Department of psychiatry in a university medical center, the Netherlands. PARTICIPANTS Patients with opioid use disorder (n = 14) on opioid maintenance treatment with a lasting wish for abstinence, who failed to reach abstinence with standard care. INTERVENTION AND MEASUREMENTS After conversion to morphine-sulphate, a single dose of ibogaine-HCl 10 mg/kg was administered and patients were monitored at regular intervals for at least 24 hours assessing QTc, blood pressure and heart rate, scale for the assessment and rating of ataxia (SARA) to assess cerebellar side effects and the delirium observation scale (DOS) to assess psychomimetic effects. FINDINGS The maximum QTc (Fridericia) prolongation was on average 95ms (range 29-146ms). Fifty percent of subjects reached a QTc of over 500ms during the observation period. In six out 14 subjects prolongation above 450ms lasted beyond 24 hours after ingestion of ibogaine. No torsades des pointes were observed. Severe transient ataxia with inability to walk without support was seen in all patients. Withdrawal and psychomimetic effects were mostly well-tolerated and manageable (11/14 did not return to morphine within 24 hours, DOS scores remained below threshold). CONCLUSIONS This open-label observational study found that ibogaine treatment of patients with opioid use disorder can induce a clinically relevant but reversible QTc prolongation, bradycardia, and severe ataxia.
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Affiliation(s)
- Thomas Knuijver
- IrisZorg verslavingszorgArnhemthe Netherlands,Nijmegen Institute for Science Practitioners in Addiction (NISPA)Nijmegenthe Netherlands,Department of Pharmacology–ToxicologyRadboud UMC NijmegenNijmegenthe Netherlands
| | - Arnt Schellekens
- Nijmegen Institute for Science Practitioners in Addiction (NISPA)Nijmegenthe Netherlands,Department of PsychiatryRadboud UMCNijmegenthe Netherlands
| | - Maarten Belgers
- IrisZorg verslavingszorgArnhemthe Netherlands,Nijmegen Institute for Science Practitioners in Addiction (NISPA)Nijmegenthe Netherlands
| | - Rogier Donders
- Department for Health EvidenceRadboud UMC NijmegenNijmegenthe Netherlands
| | | | - Kees Kramers
- Department of Pharmacology–ToxicologyRadboud UMC NijmegenNijmegenthe Netherlands
| | - Robbert Verkes
- Department of PsychiatryRadboud UMCNijmegenthe Netherlands,Centre of Forensic PsychiatryPompe KliniekNijmegenthe Netherlands
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12
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Lukasiewicz K, Baker JJ, Zuo Y, Lu J. Serotonergic Psychedelics in Neural Plasticity. Front Mol Neurosci 2021; 14:748359. [PMID: 34712118 PMCID: PMC8545892 DOI: 10.3389/fnmol.2021.748359] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2021] [Accepted: 09/13/2021] [Indexed: 12/15/2022] Open
Abstract
Psychedelics, compounds that can induce dramatic changes in conscious experience, have been used by humans for centuries. Recent studies have shown that certain psychedelics can induce neural plasticity by promoting neurite growth and synapse formation. In this review, we focus on the role of classical serotonergic psychedelics in neural plasticity and discuss its implication for their therapeutic potentials.
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Affiliation(s)
- Kacper Lukasiewicz
- Department of Molecular, Cell and Developmental Biology, University of California, Santa Cruz, Santa Cruz, CA, United States
| | - Jacob J Baker
- Department of Molecular, Cell and Developmental Biology, University of California, Santa Cruz, Santa Cruz, CA, United States
| | - Yi Zuo
- Department of Molecular, Cell and Developmental Biology, University of California, Santa Cruz, Santa Cruz, CA, United States
| | - Ju Lu
- Department of Molecular, Cell and Developmental Biology, University of California, Santa Cruz, Santa Cruz, CA, United States
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13
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Baumel Y, Yamin HG, Cohen D. Cerebellar nuclei neurons display aberrant oscillations during harmaline-induced tremor. Heliyon 2021; 7:e08119. [PMID: 34660929 PMCID: PMC8503592 DOI: 10.1016/j.heliyon.2021.e08119] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2021] [Revised: 07/13/2021] [Accepted: 09/29/2021] [Indexed: 01/21/2023] Open
Abstract
Essential tremor, a common, debilitating motor disorder, is thought to be caused by cerebellar malfunction. It has been shown that rhythmic Purkinje cell firing is both necessary and sufficient to induce body tremor. During tremor, cerebellar nuclei (CN) cells also display oscillatory activity. This study examined whether rhythmic activity in the CN characterizes the occurrence of body tremor, or alternatively, whether aberrant bursting activity underlies body tremor. Cerebellar nuclei activity was chronically recorded and analyzed in freely moving and in harmaline treated rats. CN neurons displayed rhythmic activity in both conditions, but the number of oscillatory neurons and the relative oscillation time were significantly higher under harmaline. The dominant frequencies of the oscillations were broadly distributed under harmaline and the likelihood that two simultaneously recorded neurons would co-oscillate and their oscillation coherence were significantly lower. It is argued that these alterations rather than neuronal rhythmicity per se underlie harmaline-induced body tremor.
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Affiliation(s)
- Yuval Baumel
- The Leslie and Susan Gonda Multidisciplinary Brain Research Center, Bar-Ilan University, Ramat-Gan, 52900, Israel
| | - Hagar G Yamin
- The Leslie and Susan Gonda Multidisciplinary Brain Research Center, Bar-Ilan University, Ramat-Gan, 52900, Israel
| | - Dana Cohen
- The Leslie and Susan Gonda Multidisciplinary Brain Research Center, Bar-Ilan University, Ramat-Gan, 52900, Israel
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14
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Iyer RN, Favela D, Zhang G, Olson DE. The iboga enigma: the chemistry and neuropharmacology of iboga alkaloids and related analogs. Nat Prod Rep 2021; 38:307-329. [PMID: 32794540 DOI: 10.1039/d0np00033g] [Citation(s) in RCA: 31] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Covering: 2000 up to 2020 Few classes of natural products have inspired as many chemists and biologists as have the iboga alkaloids. This family of monoterpenoid indole alkaloids includes the anti-addictive compound ibogaine as well as catharanthine, a precursor to the chemotherapeutic vinblastine. Despite being known for over 120 years, these small molecules continue to challenge our assumptions about biosynthetic pathways, catalyze our creativity for constructing complex architectures, and embolden new approaches for treating mental illness. This review will cover recent advances in both the biosynthesis and chemical synthesis of iboga alkaloids as well as their use as next-generation neurotherapeutics. Whenever appropriate, we provide historical context for the discoveries of the past decade and indicate areas that have yet to be resolved. While significant progress regarding their chemistry and pharmacology has been made since the 1960s, it is clear that the iboga alkaloids will continue to stoke scientific innovation for years to come.
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Affiliation(s)
- Rishab N Iyer
- Department of Chemistry, University of California, Davis, One Shields Avenue, Davis, CA 95616, USA.
| | - David Favela
- Department of Chemistry, University of California, Davis, One Shields Avenue, Davis, CA 95616, USA.
| | - Guoliang Zhang
- Department of Chemistry, University of California, Davis, One Shields Avenue, Davis, CA 95616, USA.
| | - David E Olson
- Department of Chemistry, University of California, Davis, One Shields Avenue, Davis, CA 95616, USA. and Department of Biochemistry & Molecular Medicine, School of Medicine, University of California, Davis, 2700 Stockton Blvd, Suite 2102, Sacramento, CA 95817, USA and Center for Neuroscience, University of California, Davis, 1544 Newton Ct, Davis, CA 95618, USA
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15
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Joshi DC, Zhang CL, Babujee L, Vevea JD, August BK, Sheng ZH, Chapman ER, Gomez TM, Chiu SY. Inappropriate Intrusion of an Axonal Mitochondrial Anchor into Dendrites Causes Neurodegeneration. Cell Rep 2020; 29:685-696.e5. [PMID: 31618636 PMCID: PMC6884150 DOI: 10.1016/j.celrep.2019.09.012] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2018] [Revised: 07/30/2019] [Accepted: 09/05/2019] [Indexed: 01/21/2023] Open
Abstract
Syntaphilin (SNPH) is a major mitochondrial anchoring protein targeted to axons and excluded from dendrites. In this study, we provide in vivo evidence that this spatial specificity is lost in Shiverer (Shi) mice, a model for progressive multiple sclerosis (MS), resulting in inappropriate intrusion of SNPH into dendrites of cerebellar Purkinje cells with neurodegenerative consequences. Thus, reconstituting dendritic SNPH intrusion in SNPH-KO mice by viral transduction greatly sensitizes Purkinje cells to excitotoxicity when the glutamatergic climbing fibers are stimulated. Finally, we demonstrate in vitro that overexpression of SNPH in dendrites compromises neuronal viability by inducing N-methyl-D-aspartate (NMDA) excitotoxicity, reducing mitochondrial calcium uptake, and interfering with quality control of mitochondria by blocking somal mitophagy. Collectively, we propose that inappropriate immobilization of dendritic mitochondria by SNPH intrusion produces excitotoxicity and suggest that interception of dendritic SNPH intrusion is a therapeutic strategy to combat neurodegeneration.
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Affiliation(s)
- Dinesh C Joshi
- Department of Neuroscience, School of Medicine and Public Health, University of Wisconsin, Madison, WI, USA
| | - Chuan-Li Zhang
- Department of Neuroscience, School of Medicine and Public Health, University of Wisconsin, Madison, WI, USA
| | - Lavanya Babujee
- Department of Plant Pathology, College of Agricultural and Life Sciences, University of Wisconsin, Madison, WI, USA
| | - Jason D Vevea
- Howard Hughes Medical Institute and Department of Neuroscience, School of Medicine and Public Health, University of Wisconsin, Madison, WI, USA
| | - Benjamin K August
- Medical School Electron Microscope Facility, University of Wisconsin, Madison, WI, USA
| | - Zu-Hang Sheng
- Synaptic Functions Section, Porter Neuroscience Research Center, National Institute of Neurological Disorders and Stroke, NIH, Bethesda, MD, USA
| | - Edwin R Chapman
- Howard Hughes Medical Institute and Department of Neuroscience, School of Medicine and Public Health, University of Wisconsin, Madison, WI, USA
| | - Timothy M Gomez
- Department of Neuroscience, School of Medicine and Public Health, University of Wisconsin, Madison, WI, USA
| | - Shing Yan Chiu
- Department of Neuroscience, School of Medicine and Public Health, University of Wisconsin, Madison, WI, USA.
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16
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Human CYP2D6 in the Brain Is Protective Against Harmine-Induced Neurotoxicity: Evidence from Humanized CYP2D6 Transgenic Mice. Mol Neurobiol 2020; 57:4608-4621. [PMID: 32761352 DOI: 10.1007/s12035-020-02050-w] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2020] [Accepted: 07/28/2020] [Indexed: 10/25/2022]
Abstract
CYP2D6 metabolically inactivates several neurotoxins, including beta-carbolines, which are implicated in neurodegenerative diseases. Variation in CYP2D6 within the brain may alter local inactivation of neurotoxic beta-carbolines, thereby influencing neurotoxicity. The beta-carboline harmine, which induces hypothermia and tremor, is metabolized by CYP2D6 to the non-hypothermic/non-tremorgenic harmol. Transgenic mice (TG), expressing human CYP2D6 in addition to their endogenous mouse CYP2D, experience less harmine-induced hypothermia and tremor compared with wild-type mice (WT). We first sought to elucidate the role of CYP2D in general within the brain in harmine-induced hypothermia and tremor severity. A 4-h intracerebroventricular (ICV) pretreatment with the CYP2D inhibitor propranolol increased harmine-induced hypothermia and tremor in TG and increased harmine-induced hypothermia in WT. We next sought to specifically demonstrate that human CYP2D6 expressed in TG brain altered harmine response severity. A 24-h ICV propranolol pretreatment, which selectively and irreversibly inhibits human CYP2D6 in TG brain, increased harmine-induced hypothermia. This 24-h pretreatment had no impact on harmine response in WT, as propranolol is not an irreversible inhibitor of mouse CYP2D in the brain, thus confirming no off-target effects of ICV propranolol pretreatment. Human CYP2D6 activity in TG brain was sufficient in vivo to mitigate harmine-induced neurotoxicity. These findings suggest that human CYP2D6 in the brain is protective against beta-carboline-induced neurotoxicity and that the extensive interindividual variability in CYP2D6 expression in human brain may contribute to variation in susceptibility to certain neurotoxin-associated neurodegenerative disorders.
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17
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Identification of Novel Pathways Associated with Patterned Cerebellar Purkinje Neuron Degeneration in Niemann-Pick Disease, Type C1. Int J Mol Sci 2019; 21:ijms21010292. [PMID: 31906248 PMCID: PMC6981888 DOI: 10.3390/ijms21010292] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2019] [Revised: 12/23/2019] [Accepted: 12/25/2019] [Indexed: 01/22/2023] Open
Abstract
Niemann-Pick disease, type C1 (NPC1) is a lysosomal disease characterized by progressive cerebellar ataxia. In NPC1, a defect in cholesterol transport leads to endolysosomal storage of cholesterol and decreased cholesterol bioavailability. Purkinje neurons are sensitive to the loss of NPC1 function. However, degeneration of Purkinje neurons is not uniform. They are typically lost in an anterior-to-posterior gradient with neurons in lobule X being resistant to neurodegeneration. To gain mechanistic insight into factors that protect or potentiate Purkinje neuron loss, we compared RNA expression in cerebellar lobules III, VI, and X from control and mutant mice. An unexpected finding was that the gene expression differences between lobules III/VI and X were more pronounced than those observed between mutant and control mice. Functional analysis of genes with anterior to posterior gene expression differences revealed an enrichment of genes related to neuronal cell survival within the posterior cerebellum. This finding is consistent with the observation, in multiple diseases, that posterior Purkinje neurons are, in general, resistant to neurodegeneration. To our knowledge, this is the first study to evaluate anterior to posterior transcriptome-wide changes in gene expression in the cerebellum. Our data can be used to not only explore potential pathological mechanisms in NPC1, but also to further understand cerebellar biology.
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18
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Alexander CJ, Hammer JA. An Improved Method for Differentiating Mouse Embryonic Stem Cells into Cerebellar Purkinje Neurons. THE CEREBELLUM 2019; 18:406-421. [PMID: 30729383 DOI: 10.1007/s12311-019-1007-0] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
While mixed primary cerebellar cultures prepared from embryonic tissue have proven valuable for dissecting structure-function relationships in cerebellar Purkinje neurons (PNs), this technique is technically challenging and often yields few cells. Recently, mouse embryonic stem cells (mESCs) have been successfully differentiated into PNs, although the published methods are very challenging as well. The focus of this study was to simplify the differentiation of mESCs into PNs. Using a recently described neural differentiation media, we generate monolayers of neural progenitor cells from mESCs and differentiate them into PN precursors using specific extrinsic factors. These PN precursors are then differentiated into mature PNs by co-culturing them with granule neuron (GN) precursors also derived from neural progenitors using different extrinsic factors. The morphology of mESC-derived PNs is indistinguishable from PNs grown in primary culture in terms of gross morphology, spine length, and spine density. Furthermore, mESC-derived PNs express Calbindin D28K, IP3R1, IRBIT, PLCβ4, PSD93, and myosin IIB-B2, all of which are either PN-specific or highly expressed in PNs. Moreover, we show that mESC-derived PNs form synapses with GN-like cells as in primary culture, express proteins driven by the PN-specific promoter Pcp2/L7, and exhibit the defect in spine ER inheritance seen in PNs isolated from dilute-lethal (myosin Va-null) mice when expressing a Pcp2/L7-driven miRNA directed against myosin Va. Finally, we define a novel extracellular matrix formulation that reproducibly yields monolayer cultures conducive for high-resolution imaging. Our improved method for differentiating mESCs into PNs should facilitate the dissection of molecular mechanisms and disease phenotypes in PNs.
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Affiliation(s)
- Christopher J Alexander
- Cell and Developmental Biology Center, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD, USA
| | - John A Hammer
- Cell and Developmental Biology Center, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD, USA.
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19
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Alexander CJ, Wagner W, Copeland NG, Jenkins NA, Hammer JA. Creation of a myosin Va-TAP-tagged mouse and identification of potential myosin Va-interacting proteins in the cerebellum. Cytoskeleton (Hoboken) 2019; 75:395-409. [PMID: 29979496 DOI: 10.1002/cm.21474] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2018] [Revised: 06/19/2018] [Accepted: 06/27/2018] [Indexed: 12/29/2022]
Abstract
The actin-based motor myosin Va transports numerous cargos, including the smooth endoplasmic reticulum (SER) in cerebellar Purkinje neurons (PNs) and melanosomes in melanocytes. Identifying proteins that interact with this myosin is key to understanding its cellular functions. Toward that end, we used recombineering to insert via homologous recombination a tandem affinity purification (TAP) tag composed of the immunoglobulin G-binding domain of protein A, a tobacco etch virus cleavage site, and a FLAG tag into the mouse MYO5A locus immediately after the initiation codon. Importantly, we provide evidence that the TAP-tagged version of myosin Va (TAP-MyoVa) functions normally in terms of SER transport in PNs and melanosome positioning in melanocytes. Given this and other evidence that TAP-MyoVa is fully functional, we purified it together with associated proteins directly from juvenile mouse cerebella and subjected the samples to mass spectroscopic analyses. As expected, known myosin Va-binding partners like dynein light chain were identified. Importantly, numerous novel interacting proteins were also tentatively identified, including guanine nucleotide-binding protein G(o) subunit alpha (Gnao1), a biomarker for schizophrenia. Consistently, an antibody to Gnao1 immunoprecipitates myosin Va, and Gnao1's localization to PN dendritic spines depends on myosin Va. The mouse model created here should facilitate the identification of novel myosin Va-binding partners, which in turn should advance our understanding of the roles played by this important myosin in vivo.
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Affiliation(s)
- Christopher J Alexander
- Cell Biology and Physiology Center, National Heart, Lung and Blood Institute, National Institutes of Health, Bethesda, Maryland
| | - Wolfgang Wagner
- Center for Molecular Neurobiology (ZMNH), Department of Molecular Genetics, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Neal G Copeland
- The University of Texas MD Anderson, Department of Genetics, Cancer Center, Houston, Texas
| | - Nancy A Jenkins
- The University of Texas MD Anderson, Department of Genetics, Cancer Center, Houston, Texas
| | - John A Hammer
- Cell Biology and Physiology Center, National Heart, Lung and Blood Institute, National Institutes of Health, Bethesda, Maryland
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20
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Lee J, Jo HJ, Kim I, Lee J, Min HK, In MH, Knight EJ, Chang SY. Mapping BOLD Activation by Pharmacologically Evoked Tremor in Swine. Front Neurosci 2019; 13:985. [PMID: 31619955 PMCID: PMC6759958 DOI: 10.3389/fnins.2019.00985] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2019] [Accepted: 09/02/2019] [Indexed: 11/26/2022] Open
Abstract
Harmaline-induced tremor is one of the most commonly utilized disease models for essential tremor (ET). However, the underlying neural networks involved in harmaline-induced tremor and the degree to which these are a representative model of the pathophysiologic mechanism of ET are incompletely understood. In this study, we evaluated the functional brain network effects induced by systemic injection of harmaline using pharmacological functional magnetic resonance imaging (ph-fMRI) in the swine model. With harmaline administration, we observed significant activation changes in cerebellum, thalamus, and inferior olivary nucleus (ION). In addition, inter-regional correlations in activity between cerebellum and deep cerebellar nuclei and between cerebellum and thalamus were significantly enhanced. These harmaline-induced effects gradually decreased with repeated administration of drug, replicating the previously demonstrated ‘tolerance’ effect. This study demonstrates that harmaline-induced tremor is associated with activity changes in brain regions previously implicated in humans with ET. Thus, harmaline-induction of tremor in the swine may be a useful model to explore the neurological effects of novel therapeutic agents and/or neuromodulation techniques for ET.
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Affiliation(s)
- Jeyeon Lee
- Department of Neurologic Surgery, Mayo Clinic, Rochester, MN, United States
| | - Hang Joon Jo
- Department of Neurologic Surgery, Mayo Clinic, Rochester, MN, United States.,Department of Radiology, Mayo Clinic, Rochester, MN, United States.,Department of Neurology, Mayo Clinic, Rochester, MN, United States.,Department of Physiology, College of Medicine, Hanyang University, Seoul, South Korea
| | - Inyong Kim
- Department of Neurology, Mayo Clinic, Rochester, MN, United States
| | - Jihyun Lee
- Laboratory of Brain and Cognitive Sciences for Convergence Medicine, Hallym University College of Medicine, Anyang, South Korea
| | - Hoon-Ki Min
- Department of Radiology, Mayo Clinic, Rochester, MN, United States
| | - Myung-Ho In
- Department of Radiology, Mayo Clinic, Rochester, MN, United States
| | - Emily J Knight
- Department of Developmental Behavioral Pediatrics, University of Rochester, Rochester, NY, United States
| | - Su-Youne Chang
- Department of Neurologic Surgery, Mayo Clinic, Rochester, MN, United States.,Department of Physiology and Biomedical Engineering, Mayo Clinic, Rochester, MN, United States
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21
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Juttukonda MR, Franco G, Englot DJ, Lin YC, Petersen KJ, Trujillo P, Hedera P, Landman BA, Kang H, Donahue MJ, Konrad PE, Dawant BM, Claassen DO. White matter differences between essential tremor and Parkinson disease. Neurology 2018; 92:e30-e39. [PMID: 30504432 DOI: 10.1212/wnl.0000000000006694] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2018] [Accepted: 09/05/2018] [Indexed: 11/15/2022] Open
Abstract
OBJECTIVE To assess white matter integrity in patients with essential tremor (ET) and Parkinson disease (PD) with moderate to severe motor impairment. METHODS Sedated participants with ET (n = 57) or PD (n = 99) underwent diffusion tensor imaging (DTI) and fractional anisotropy, mean diffusivity, axial diffusivity, and radial diffusivity values were computed. White matter tracts were defined using 3 well-described atlases. To determine candidate white matter regions that differ between ET and PD groups, a bootstrapping analysis was applied using the least absolute shrinkage and selection operator. Linear regression was applied to assess magnitude and direction of differences in DTI metrics between ET and PD populations in the candidate regions. RESULTS Fractional anisotropy values that differentiate ET from PD localize primarily to thalamic and visual-related pathways, while diffusivity differences localized to the cerebellar peduncles. Patients with ET exhibited lower fractional anisotropy values than patients with PD in the lateral geniculate body (p < 0.01), sagittal stratum (p = 0.01), forceps major (p = 0.02), pontine crossing tract (p = 0.03), and retrolenticular internal capsule (p = 0.04). Patients with ET exhibited greater radial diffusivity values than patients with PD in the superior cerebellar peduncle (p < 0.01), middle cerebellar peduncle (p = 0.05), and inferior cerebellar peduncle (p = 0.05). CONCLUSIONS Regionally, distinctive white matter microstructural values in patients with ET localize to the cerebellar peduncles and thalamo-cortical visual pathways. These findings complement recent functional imaging studies in ET but also extend our understanding of putative physiologic features that account for distinctions between ET and PD.
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Affiliation(s)
- Meher R Juttukonda
- From the Departments of Radiology and Radiological Sciences (M.R.J., M.J.D.), Neurological Surgery (D.J.E., P.E.K.), Biostatistics (Y.-C.L., H.K.), Neurology (P.T., P.H., M.J.D.), and Psychiatry (M.J.D.), Vanderbilt University Medical Center, Nashville, TN; Department of Pathophysiology and Transplantation (G.F.) University of Milan, Italy; and Chemical and Physical Biology Program (K.J.P.) and Departments of Electrical Engineering (B.A.L., B.M.D.), Computer Engineering (B.A.L., B.M.D.), Computer Science and Biomedical Engineering (B.A.L., B.M.D.), and Neurology (D.O.C.), Vanderbilt University, Nashville, TN
| | - Giulia Franco
- From the Departments of Radiology and Radiological Sciences (M.R.J., M.J.D.), Neurological Surgery (D.J.E., P.E.K.), Biostatistics (Y.-C.L., H.K.), Neurology (P.T., P.H., M.J.D.), and Psychiatry (M.J.D.), Vanderbilt University Medical Center, Nashville, TN; Department of Pathophysiology and Transplantation (G.F.) University of Milan, Italy; and Chemical and Physical Biology Program (K.J.P.) and Departments of Electrical Engineering (B.A.L., B.M.D.), Computer Engineering (B.A.L., B.M.D.), Computer Science and Biomedical Engineering (B.A.L., B.M.D.), and Neurology (D.O.C.), Vanderbilt University, Nashville, TN
| | - Dario J Englot
- From the Departments of Radiology and Radiological Sciences (M.R.J., M.J.D.), Neurological Surgery (D.J.E., P.E.K.), Biostatistics (Y.-C.L., H.K.), Neurology (P.T., P.H., M.J.D.), and Psychiatry (M.J.D.), Vanderbilt University Medical Center, Nashville, TN; Department of Pathophysiology and Transplantation (G.F.) University of Milan, Italy; and Chemical and Physical Biology Program (K.J.P.) and Departments of Electrical Engineering (B.A.L., B.M.D.), Computer Engineering (B.A.L., B.M.D.), Computer Science and Biomedical Engineering (B.A.L., B.M.D.), and Neurology (D.O.C.), Vanderbilt University, Nashville, TN
| | - Ya-Chen Lin
- From the Departments of Radiology and Radiological Sciences (M.R.J., M.J.D.), Neurological Surgery (D.J.E., P.E.K.), Biostatistics (Y.-C.L., H.K.), Neurology (P.T., P.H., M.J.D.), and Psychiatry (M.J.D.), Vanderbilt University Medical Center, Nashville, TN; Department of Pathophysiology and Transplantation (G.F.) University of Milan, Italy; and Chemical and Physical Biology Program (K.J.P.) and Departments of Electrical Engineering (B.A.L., B.M.D.), Computer Engineering (B.A.L., B.M.D.), Computer Science and Biomedical Engineering (B.A.L., B.M.D.), and Neurology (D.O.C.), Vanderbilt University, Nashville, TN
| | - Kalen J Petersen
- From the Departments of Radiology and Radiological Sciences (M.R.J., M.J.D.), Neurological Surgery (D.J.E., P.E.K.), Biostatistics (Y.-C.L., H.K.), Neurology (P.T., P.H., M.J.D.), and Psychiatry (M.J.D.), Vanderbilt University Medical Center, Nashville, TN; Department of Pathophysiology and Transplantation (G.F.) University of Milan, Italy; and Chemical and Physical Biology Program (K.J.P.) and Departments of Electrical Engineering (B.A.L., B.M.D.), Computer Engineering (B.A.L., B.M.D.), Computer Science and Biomedical Engineering (B.A.L., B.M.D.), and Neurology (D.O.C.), Vanderbilt University, Nashville, TN
| | - Paula Trujillo
- From the Departments of Radiology and Radiological Sciences (M.R.J., M.J.D.), Neurological Surgery (D.J.E., P.E.K.), Biostatistics (Y.-C.L., H.K.), Neurology (P.T., P.H., M.J.D.), and Psychiatry (M.J.D.), Vanderbilt University Medical Center, Nashville, TN; Department of Pathophysiology and Transplantation (G.F.) University of Milan, Italy; and Chemical and Physical Biology Program (K.J.P.) and Departments of Electrical Engineering (B.A.L., B.M.D.), Computer Engineering (B.A.L., B.M.D.), Computer Science and Biomedical Engineering (B.A.L., B.M.D.), and Neurology (D.O.C.), Vanderbilt University, Nashville, TN
| | - Peter Hedera
- From the Departments of Radiology and Radiological Sciences (M.R.J., M.J.D.), Neurological Surgery (D.J.E., P.E.K.), Biostatistics (Y.-C.L., H.K.), Neurology (P.T., P.H., M.J.D.), and Psychiatry (M.J.D.), Vanderbilt University Medical Center, Nashville, TN; Department of Pathophysiology and Transplantation (G.F.) University of Milan, Italy; and Chemical and Physical Biology Program (K.J.P.) and Departments of Electrical Engineering (B.A.L., B.M.D.), Computer Engineering (B.A.L., B.M.D.), Computer Science and Biomedical Engineering (B.A.L., B.M.D.), and Neurology (D.O.C.), Vanderbilt University, Nashville, TN
| | - Bennett A Landman
- From the Departments of Radiology and Radiological Sciences (M.R.J., M.J.D.), Neurological Surgery (D.J.E., P.E.K.), Biostatistics (Y.-C.L., H.K.), Neurology (P.T., P.H., M.J.D.), and Psychiatry (M.J.D.), Vanderbilt University Medical Center, Nashville, TN; Department of Pathophysiology and Transplantation (G.F.) University of Milan, Italy; and Chemical and Physical Biology Program (K.J.P.) and Departments of Electrical Engineering (B.A.L., B.M.D.), Computer Engineering (B.A.L., B.M.D.), Computer Science and Biomedical Engineering (B.A.L., B.M.D.), and Neurology (D.O.C.), Vanderbilt University, Nashville, TN
| | - Hakmook Kang
- From the Departments of Radiology and Radiological Sciences (M.R.J., M.J.D.), Neurological Surgery (D.J.E., P.E.K.), Biostatistics (Y.-C.L., H.K.), Neurology (P.T., P.H., M.J.D.), and Psychiatry (M.J.D.), Vanderbilt University Medical Center, Nashville, TN; Department of Pathophysiology and Transplantation (G.F.) University of Milan, Italy; and Chemical and Physical Biology Program (K.J.P.) and Departments of Electrical Engineering (B.A.L., B.M.D.), Computer Engineering (B.A.L., B.M.D.), Computer Science and Biomedical Engineering (B.A.L., B.M.D.), and Neurology (D.O.C.), Vanderbilt University, Nashville, TN
| | - Manus J Donahue
- From the Departments of Radiology and Radiological Sciences (M.R.J., M.J.D.), Neurological Surgery (D.J.E., P.E.K.), Biostatistics (Y.-C.L., H.K.), Neurology (P.T., P.H., M.J.D.), and Psychiatry (M.J.D.), Vanderbilt University Medical Center, Nashville, TN; Department of Pathophysiology and Transplantation (G.F.) University of Milan, Italy; and Chemical and Physical Biology Program (K.J.P.) and Departments of Electrical Engineering (B.A.L., B.M.D.), Computer Engineering (B.A.L., B.M.D.), Computer Science and Biomedical Engineering (B.A.L., B.M.D.), and Neurology (D.O.C.), Vanderbilt University, Nashville, TN
| | - Peter E Konrad
- From the Departments of Radiology and Radiological Sciences (M.R.J., M.J.D.), Neurological Surgery (D.J.E., P.E.K.), Biostatistics (Y.-C.L., H.K.), Neurology (P.T., P.H., M.J.D.), and Psychiatry (M.J.D.), Vanderbilt University Medical Center, Nashville, TN; Department of Pathophysiology and Transplantation (G.F.) University of Milan, Italy; and Chemical and Physical Biology Program (K.J.P.) and Departments of Electrical Engineering (B.A.L., B.M.D.), Computer Engineering (B.A.L., B.M.D.), Computer Science and Biomedical Engineering (B.A.L., B.M.D.), and Neurology (D.O.C.), Vanderbilt University, Nashville, TN
| | - Benoit M Dawant
- From the Departments of Radiology and Radiological Sciences (M.R.J., M.J.D.), Neurological Surgery (D.J.E., P.E.K.), Biostatistics (Y.-C.L., H.K.), Neurology (P.T., P.H., M.J.D.), and Psychiatry (M.J.D.), Vanderbilt University Medical Center, Nashville, TN; Department of Pathophysiology and Transplantation (G.F.) University of Milan, Italy; and Chemical and Physical Biology Program (K.J.P.) and Departments of Electrical Engineering (B.A.L., B.M.D.), Computer Engineering (B.A.L., B.M.D.), Computer Science and Biomedical Engineering (B.A.L., B.M.D.), and Neurology (D.O.C.), Vanderbilt University, Nashville, TN
| | - Daniel O Claassen
- From the Departments of Radiology and Radiological Sciences (M.R.J., M.J.D.), Neurological Surgery (D.J.E., P.E.K.), Biostatistics (Y.-C.L., H.K.), Neurology (P.T., P.H., M.J.D.), and Psychiatry (M.J.D.), Vanderbilt University Medical Center, Nashville, TN; Department of Pathophysiology and Transplantation (G.F.) University of Milan, Italy; and Chemical and Physical Biology Program (K.J.P.) and Departments of Electrical Engineering (B.A.L., B.M.D.), Computer Engineering (B.A.L., B.M.D.), Computer Science and Biomedical Engineering (B.A.L., B.M.D.), and Neurology (D.O.C.), Vanderbilt University, Nashville, TN.
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Erekat NS. Cerebellar Upregulation of Cell Surface Death Receptor-Mediated Apoptotic Factors in Harmaline-Induced Tremor: An Immunohistochemistry Study. J Cell Death 2018; 11:1179066018809091. [PMID: 30450003 PMCID: PMC6236486 DOI: 10.1177/1179066018809091] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2018] [Accepted: 09/30/2018] [Indexed: 11/24/2022] Open
Abstract
Active caspase-3-mediated apoptosis has been implicated in the pathogenesis of
harmaline-induced tremor. The aim of this study is to illustrate the impact of
tremor induction on the expression of factors mediating the cell surface death
receptor–dependent apoptosis. A total of 20 normal Wistar rats were randomly
selected and equally divided into control and experimental groups. Tremor was
induced in the experimental group by injecting the rats with a single dose of
harmaline (50 mg/kg). After that, cerebellar tissues were evaluated by
immunohistochemistry to examine the expression of tumor necrosis factor α
(TNF-α) and active caspase-8 in the 2 groups of animals. TNF-α and active
caspase-8 expression was significantly higher in cerebella from experimental
rats compared with that in those from the control rats (P
value < .01). Thus, our present data suggest the association of tremor
induction with the cerebellar overexpression of TNF-α and active caspase-8,
correlative with Purkinje cell (PC) loss indicated by loss of calbindin
immunoreactivity, indicating the induction of the cell surface death
receptor–mediated apoptosis.
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Affiliation(s)
- Nour S Erekat
- Department of Anatomy, Faculty of Medicine, Jordan University of Science and Technology, Irbid, Jordan
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Barsuglia JP, Polanco M, Palmer R, Malcolm BJ, Kelmendi B, Calvey T. A case report SPECT study and theoretical rationale for the sequential administration of ibogaine and 5-MeO-DMT in the treatment of alcohol use disorder. PROGRESS IN BRAIN RESEARCH 2018; 242:121-158. [PMID: 30471678 DOI: 10.1016/bs.pbr.2018.08.002] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Ibogaine is a plant-derived alkaloid and dissociative psychedelic that demonstrates anti-addictive properties with several substances of abuse, including alcohol. 5-methoxy-N,N-dimethyltryptamine (5-MeO-DMT) is a naturally occurring psychedelic known to occasion potent mystical-type experiences and also demonstrates anti-addictive properties. The potential therapeutic effects of both compounds in treating alcohol use disorder require further investigation and there are no published human neuroimaging findings of either treatment to date. We present the case of a 31-year-old male military veteran with moderate alcohol use disorder who sought treatment at an inpatient clinic in Mexico that utilized a sequential protocol with ibogaine hydrochloride (1550mg, 17.9mg/kg) on day 1, followed by vaporized 5-MeO-DMT (bufotoxin source 50mg, estimated 5-MeO-DMT content, 5-7mg) on day 3. The patient received SPECT neuroimaging that included a resting-state protocol before, and 3 days after completion of the program. During the patient's ibogaine treatment, he experienced dream-like visions that included content pertaining to his alcohol use and resolution of past developmental traumas. He described his treatment with 5-MeO-DMT as a peak transformational and spiritual breakthrough. On post-treatment SPECT neuroimaging, increases in brain perfusion were noted in bilateral caudate nuclei, left putamen, right insula, as well as temporal, occipital, and cerebellar regions compared to the patient's baseline scan. The patient reported improvement in mood, cessation of alcohol use, and reduced cravings at 5 days post-treatment, effects which were sustained at 1 month, with a partial return to mild alcohol use at 2 months. In this case, serial administration of ibogaine and 5-MeO-DMT resulted in increased perfusion in multiple brain regions broadly associated with alcohol use disorders and known pharmacology of both compounds, which coincided with a short-term therapeutic outcome. We present theoretical considerations regarding the potential of both psychedelic medicines in treating alcohol use disorders in the context of these isolated findings, and areas for future investigation.
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Affiliation(s)
- Joseph P Barsuglia
- Crossroads Treatment Center, Tijuana, Mexico; Mission Within, Oakland, CA, United States; New School Research, LLC, North Hollywood, CA, United States; Terra Incognita Project, NGO, Ben Lomond, CA, United States.
| | - Martin Polanco
- Crossroads Treatment Center, Tijuana, Mexico; Mission Within, Oakland, CA, United States
| | - Robert Palmer
- Yale School of Medicine, New Haven, CT, United States
| | - Benjamin J Malcolm
- College of Pharmacy, Western University of Health Sciences, Pomona, CA, United States
| | - Benjamin Kelmendi
- Department of Psychiatry, Yale University School of Medicine, New Haven, CT, United States
| | - Tanya Calvey
- Faculty of Health Sciences, University of the Witwatersrand Medical School, Johannesburg, South Africa
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24
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Wasko MJ, Witt-Enderby PA, Surratt CK. DARK Classics in Chemical Neuroscience: Ibogaine. ACS Chem Neurosci 2018; 9:2475-2483. [PMID: 30216039 DOI: 10.1021/acschemneuro.8b00294] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
The West African iboga plant has been used for centuries by the Bwiti and Mbiri tribes to induce hallucinations during religious ceremonies. Ibogaine, the principal alkaloid responsible for iboga's psychedelic properties, was isolated and sold as an antidepressant in France for decades before its adverse effects precipitated its removal from the market. An ibogaine resurgence in the 1960s was driven by U.S. heroin addicts who claimed that ibogaine cured their opiate addictions. Behavioral pharmacologic studies in animal models provided evidence that ibogaine could blunt self-administration of not only opiates but cocaine, amphetamines, and nicotine. Ibogaine displays moderate-to-weak affinities for a wide spectrum of receptor and transporter proteins; recent work suggests that its actions at nicotinic acetylcholine receptor subtypes may underlie its reputed antiopiate effects. At micromolar levels, ibogaine is neurotoxic and cardiotoxic and has been linked to several deaths by cardiac arrest. Structure-activity studies led to the isolation of the ibogaine analog 18-methoxycoronaridine (18-MC), an α3β4 nicotinic receptor modulator that retains ibogaine's anticraving properties with few or no adverse effects. Clinical trials of 18-MC treatment of nicotine addiction are pending. Ibogaine analogs may also hold promise for treating anxiety and depression via the "psychedelic-assisted therapy" approach that employs hallucinogens including psilocybin and methylenedioxymethamphetamine ("ecstasy").
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Affiliation(s)
- Michael J. Wasko
- Division of Pharmaceutical, Administrative and Social Sciences, Duquesne University School of Pharmacy, 600 Forbes Avenue, Pittsburgh, Pennsylvania 15282, United States
| | - Paula A. Witt-Enderby
- Division of Pharmaceutical, Administrative and Social Sciences, Duquesne University School of Pharmacy, 600 Forbes Avenue, Pittsburgh, Pennsylvania 15282, United States
| | - Christopher K. Surratt
- Arnold & Marie Schwartz College of Pharmacy and Health Sciences, Long Island University−Brooklyn, 75 DeKalb Avenue, Brooklyn, New York 11201, United States
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25
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Corkery JM. Ibogaine as a treatment for substance misuse: Potential benefits and practical dangers. PROGRESS IN BRAIN RESEARCH 2018; 242:217-257. [PMID: 30471681 DOI: 10.1016/bs.pbr.2018.08.005] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Ibogaine is an indole alkaloid found in the root bark of the Iboga shrub native to west Africa possessing hallucinogenic properties. For centuries it has been used in religious ceremonies and to gain spiritual enlightenment. However, since the early 1960s, its apparent ability to reduce craving for psychoactive substances including alcohol, cocaine, methamphetamine, opiates, and nicotine has led to its use in detoxification treatments. In many instances, clients receive treatment in non-medical settings, with little by way of robust scientific clinical trials. This chapter provides an overview of the potential benefits that could arise from such research. This is balanced against the serious adverse effects that can occur due to undiagnosed health conditions and/or concomitant use of other drugs. A detailed update is provided of the 33 deaths known to have occurred, including 5 in the UK. Looking forward, there is a need to develop better opiate detoxification treatment against a background of increasing opioid-related fatalities. A congener of ibogaine, 18-MC, appears to be safer and is to undergo clinical trials. In the meantime, would-be consumers and treatment providers must make more careful, detailed risk-assessments before using ibogaine. Treatment outcomes, including deaths, need to be accurately recorded and published.
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Affiliation(s)
- John Martin Corkery
- Psychopharmacology, Drug Misuse and Novel Psychoactive Substances Research Unit, School of Life and Medical Sciences, University of Hertfordshire, Hatfield, Hertfordshire, United Kingdom.
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26
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Pan MK, Ni CL, Wu YC, Li YS, Kuo SH. Animal Models of Tremor: Relevance to Human Tremor Disorders. Tremor Other Hyperkinet Mov (N Y) 2018; 8:587. [PMID: 30402338 PMCID: PMC6214818 DOI: 10.7916/d89s37mv] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2018] [Accepted: 08/10/2018] [Indexed: 12/17/2022] Open
Abstract
Background Tremor is the most common movement disorder; however, the pathophysiology of tremor remains elusive. While several neuropathological alterations in tremor disorders have been observed in post-mortem studies of human brains, a full understanding of the relationship between brain circuitry alterations and tremor requires testing in animal models. Additionally, tremor animal models are critical for our understanding of tremor pathophysiology, and/or to serve as a platform for therapy development. Methods A PubMed search was conducted in May 2018 to identify published papers for review. Results The methodology used in most studies on animal models of tremor lacks standardized measurement of tremor frequency and amplitude; instead, these studies are based on the visual inspection of phenotypes, which may fail to delineate tremor from other movement disorders such as ataxia. Of the animal models with extensive tremor characterization, harmaline-induced rodent tremor models provide an important framework showing that rhythmic and synchronous neuronal activities within the olivocerebellar circuit can drive action tremor. In addition, dopamine-depleted monkey and mouse models may develop rest tremor, highlighting the role of dopamine in rest tremor generation. Finally, other animal models of tremor have involvement of the cerebellar circuitry, leading to altered Purkinje cell physiology. Discussion Both the cerebellum and the basal ganglia are likely to play a role in tremor generation. While the cerebellar circuitry can generate rhythmic movements, the nigrostriatal system is likely to modulate the tremor circuit. Tremor disorders are heterogeneous in nature. Therefore, each animal model may represent a subset of tremor disorders, which collectively can advance our understanding of tremor.
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Affiliation(s)
- Ming-Kai Pan
- Department of Medical Research, National Taiwan University, Taipei, TW
| | - Chun-Lun Ni
- Department of Neurology, College of Physicians and Surgeons, Columbia University, New York, NY, USA
| | - Yeuh-Chi Wu
- Department of Neurology, College of Physicians and Surgeons, Columbia University, New York, NY, USA
| | - Yong-Shi Li
- Department of Neurology, College of Physicians and Surgeons, Columbia University, New York, NY, USA
| | - Sheng-Han Kuo
- Department of Neurology, College of Physicians and Surgeons, Columbia University, New York, NY, USA
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Akil O, Blits B, Lustig LR, Leake PA. Virally Mediated Overexpression of Glial-Derived Neurotrophic Factor Elicits Age- and Dose-Dependent Neuronal Toxicity and Hearing Loss. Hum Gene Ther 2018; 30:88-105. [PMID: 30183384 DOI: 10.1089/hum.2018.028] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
Contemporary cochlear implants (CI) are generally very effective for remediation of severe to profound sensorineural hearing loss, but outcomes are still highly variable. Auditory nerve survival is likely one of the major factors underlying this variability. Neurotrophin therapy therefore has been proposed for CI recipients, with the goal of improving outcomes by promoting improved survival of cochlear spiral ganglion neurons (SGN) and/or residual hair cells. Previous studies have shown that glial-derived neurotrophic factor (GDNF), brain-derived neurotrophic factor, and neurotrophin-3 can rescue SGNs following insult. The current study was designed to determine whether adeno-associated virus vector serotype 5 (AAV-5) encoding either green fluorescent protein or GDNF can transduce cells in the mouse cochlea to express useful levels of neurotrophin and to approximate the optimum therapeutic dose(s) for transducing hair cells and SGN. The findings demonstrate that AAV-5 is a potentially useful gene therapy vector for the cochlea, resulting in extremely high levels of transgene expression in the cochlear inner hair cells and SGN. However, overexpression of human GDNF in newborn mice caused severe neurological symptoms and hearing loss, likely due to Purkinje cell loss and cochlear nucleus pathology. Thus, extremely high levels of transgene protein expression should be avoided, particularly for proteins that have neurological function in neonatal subjects.
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Affiliation(s)
- Omar Akil
- 1 Department of Otolaryngology-Head and Neck Surgery, University of California, San Francisco, San Francisco, California
| | - Bas Blits
- 2 Department of Research and Development, UniQure Biopharma B.V., Amsterdam, The Netherlands
| | - Lawrence R Lustig
- 3 Department of Otolaryngology-Head and Neck Surgery, Columbia University Medical Center, New York, New York
| | - Patricia A Leake
- 1 Department of Otolaryngology-Head and Neck Surgery, University of California, San Francisco, San Francisco, California
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28
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Reeber SL, Arancillo M, Sillitoe RV. Bergmann Glia are Patterned into Topographic Molecular Zones in the Developing and Adult Mouse Cerebellum. CEREBELLUM (LONDON, ENGLAND) 2018; 17:392-403. [PMID: 24906823 PMCID: PMC4291305 DOI: 10.1007/s12311-014-0571-6] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
Cerebellar circuits are patterned into an array of topographic parasagittal domains called zones. Zones are best revealed by gene expression, circuit anatomy, and cellular degeneration patterns. Thus far, the study of zones has been focused heavily on how neurons are organized. Because of this, detailed neuronal patterning maps have been established for Purkinje cells, granule cells, Golgi cells, unipolar brush cells, and also for the terminal field organization of climbing fiber and mossy fiber afferents. In comparison, however, it remains poorly understood if glial cells are also organized into zones. We have identified an Npy-Gfp BAC transgenic mouse line (Tau-Sapphire Green fluorescent protein (Gfp) is under the control of the neuropeptide Y (Npy) gene regulatory elements) that can be used to label Bergmann glial cells with Golgi-like resolution. In these adult transgenic mice, we found that Npy-Gfp expression was localized to Bergmann glia mainly in lobules VI/VII and IX/X. Using double immunofluorescence, we show that in these lobules, Npy-Gfp expression in the Bergmann glia overlaps with the pattern of the small heat shock protein HSP25, a Purkinje cell marker for zones located in lobules VI/VII and IX/X. Developmental analysis starting from the day of birth showed that HSP25 and Npy-Gfp expression follow a similar program of spatial and temporal patterning. However, loss of Npy signaling did not alter the patterning of Purkinje cell zones. We conclude that Bergmann glial cells are zonally organized and their patterns are restricted by boundaries that also confine cerebellar neurons into a topographic circuit map.
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Affiliation(s)
- Stacey L Reeber
- Department of Pathology and Immunology, Department of Neuroscience, Baylor College of Medicine, Jan and Dan Duncan Neurological Research Institute of Texas Children's Hospital, 1250 Moursund Street, Suite 1325, Houston, TX, 77030, USA
| | - Marife Arancillo
- Department of Pathology and Immunology, Department of Neuroscience, Baylor College of Medicine, Jan and Dan Duncan Neurological Research Institute of Texas Children's Hospital, 1250 Moursund Street, Suite 1325, Houston, TX, 77030, USA
| | - Roy V Sillitoe
- Department of Pathology and Immunology, Department of Neuroscience, Baylor College of Medicine, Jan and Dan Duncan Neurological Research Institute of Texas Children's Hospital, 1250 Moursund Street, Suite 1325, Houston, TX, 77030, USA.
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Lee J, Kim I, Lee J, Knight E, Cheng L, Kang SI, Jang DP, Chang SY. Development of Harmaline-induced Tremor in a Swine Model. Tremor Other Hyperkinet Mov (N Y) 2018; 8:532. [PMID: 29686939 PMCID: PMC5910538 DOI: 10.7916/d8j68tv7] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2017] [Accepted: 02/05/2018] [Indexed: 12/01/2022] Open
Abstract
Background In the field of translational neuroscience research, it is critical to utilize a large animal model to test the feasibility, safety, and functionality of novel therapies. Here, we describe a protocol for the development of a large animal model of tremor. Methods In a pig model, tremor was induced with harmaline and measured with wireless accelerometers attached to the limbs. Three different doses of harmaline were tested and three repetitive injections were made at 72-hour intervals. To fully characterize the drug-induced tremor, onset time, tremor amplitude, maintained duration, and peak tremor frequency were analyzed. Results Harmaline-induced tremor appeared immediately following intravenous injection of harmaline. Tremor was maintained over 2 hours. Its frequency was 10-16 Hz, which was independent of doses. Dose-dependent responses were observed in tremor amplitude, triggering time, and tremor-maintained duration. Repetitive injection of harmaline desensitized the harmaline effect. Discussion We provide a detailed protocol for training, drug injection, device selection, and tremor recording optimized to create a swine model of tremor with harmaline. Our protocol provides reliable tremor in pigs and suggests pig as a valid translational large animal model of tremor.
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Affiliation(s)
- Jihyun Lee
- Department of Neurologic Surgery, Mayo Clinic, Rochester, MN, USA
| | - Inyong Kim
- Department of Neurology, Mayo Clinic, Rochester, MN, USA
| | - Jeyeon Lee
- Department of Neurologic Surgery, Mayo Clinic, Rochester, MN, USA
| | - Emily Knight
- Department of Pediatrics, New York-Presbyterian Weill Cornell Medical Center, New York, NY, USA
| | - Lei Cheng
- Department of Neurosurgery, The Affiliated Hospital of Qingdao University, Qingdao, Shandong, China
| | - Shin il Kang
- Department of Biomedical Engineering, Hanyang University, Hanyang, Korea
| | - Dong Pyo Jang
- Department of Biomedical Engineering, Hanyang University, Hanyang, Korea
| | - Su-Youne Chang
- Department of Neurologic Surgery, Mayo Clinic, Rochester, MN, USA
- Department of Physiology and Biomedical Engineering, Mayo Clinic, Rochester, MN, USA
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30
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Louis ED, Lenka A. The Olivary Hypothesis of Essential Tremor: Time to Lay this Model to Rest? Tremor Other Hyperkinet Mov (N Y) 2017; 7:473. [PMID: 28966877 PMCID: PMC5618117 DOI: 10.7916/d8ff40rx] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2017] [Accepted: 06/09/2017] [Indexed: 02/08/2023] Open
Abstract
BACKGROUND Although essential tremor (ET) is the most common tremor disorder, its pathogenesis is not fully understood. The traditional model of ET, proposed in the early 1970s, posited that the inferior olivary nucleus (ION) was the prime generator of tremor in ET and that ET is a disorder of electrophysiological derangement, much like epilepsy. This article comprehensively reviews the origin and basis of this model, its merits and problems, and discusses whether it is time to lay this model to rest. METHODS A PubMed search was performed in March 2017 to identify articles for this review. RESULTS The olivary model gains support from the recognition of neurons with pacemaker property in the ION and the harmaline-induced tremor models (as the ION is the prime target of harmaline). However, the olivary model is problematic, as neurons with pacemaker property are not specific to the ION and the harmaline model does not completely represent the human disease ET. In addition, a large number of neuroimaging studies in ET have not detected structural or functional changes in the ION; rather, abnormalities have been reported in structures related to the cerebello-thalamo-cortical network. Moreover, a post-mortem study of microscopic changes in the ION did not detect any differences between ET cases and controls. DISCUSSION The olivary model largely remains a physiological construct. Numerous observations have cast considerable doubt as to the validity of this model in ET. Given the limitations of the model, we conclude that it is time now to lay this model to rest.
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Affiliation(s)
- Elan D. Louis
- Division of Movement Disorders, Department of Neurology, Yale School of Medicine, Yale University, New Haven, CT, USA
- Department of Chronic Disease Epidemiology, Yale School of Public Health, Yale University, New Haven, CT, USA
- Center for Neuroepidemiology and Clinical Neurological Research, Yale School of Medicine, Yale University, New Haven, CT, USA
| | - Abhishek Lenka
- Department of Clinical Neurosciences, National Institute of Mental Health and Neurosciences, Bangalore, India
- Department of Neurology, National Institute of Mental Health and Neurosciences, Bangalore, India
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Ragagnin A, Ezpeleta J, Guillemain A, Boudet-Devaud F, Haeberlé AM, Demais V, Vidal C, Demuth S, Béringue V, Kellermann O, Schneider B, Grant NJ, Bailly Y. Cerebellar compartmentation of prion pathogenesis. Brain Pathol 2017; 28:240-263. [PMID: 28268246 DOI: 10.1111/bpa.12503] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2016] [Accepted: 03/01/2017] [Indexed: 02/06/2023] Open
Abstract
In prion diseases, the brain lesion profile is influenced by the prion "strain" properties, the invasion route to the brain, and still unknown host cell-specific parameters. To gain insight into those endogenous factors, we analyzed the histopathological alterations induced by distinct prion strains in the mouse cerebellum. We show that 22L and ME7 scrapie prion proteins (PrP22L , PrPME7 ), but not bovine spongiform encephalopathy PrP6PB1 , accumulate in a reproducible parasagittal banding pattern in the cerebellar cortex of infected mice. Such banding pattern of PrP22L aggregation did not depend on the neuroinvasion route, but coincided with the parasagittal compartmentation of the cerebellum mostly defined by the expression of zebrins, such as aldolase C and the excitatory amino acid transporter 4, in Purkinje cells. We provide evidence that Purkinje cells display a differential, subtype-specific vulnerability to 22L prions with zebrin-expressing Purkinje cells being more resistant to prion toxicity, while in stripes where PrP22L accumulated most zebrin-deficient Purkinje cells are lost and spongiosis accentuated. In addition, in PrP22L stripes, enhanced reactive astrocyte processes associated with microglia activation support interdependent events between the topographic pattern of Purkinje cell death, reactive gliosis and PrP22L accumulation. Finally, we find that in preclinically-ill mice prion infection promotes at the membrane of astrocytes enveloping Purkinje cell excitatory synapses, upregulation of tumor necrosis factor-α receptor type 1 (TNFR1), a key mediator of the neuroinflammation process. These overall data show that Purkinje cell sensitivity to prion insult is locally restricted by the parasagittal compartmentation of the cerebellum, and that perisynaptic astrocytes may contribute to prion pathogenesis through prion-induced TNFR1 upregulation.
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Affiliation(s)
- Audrey Ragagnin
- Cytologie et Cytopathologie Neuronales, Institut des Neurosciences Cellulaires & Intégratives, CNRS UPR 3212, Strasbourg, France
| | - Juliette Ezpeleta
- INSERM UMR-S1124, Cellules Souches, Signalisation et Prions, Université Paris Descartes, Paris, France
| | - Aurélie Guillemain
- Cytologie et Cytopathologie Neuronales, Institut des Neurosciences Cellulaires & Intégratives, CNRS UPR 3212, Strasbourg, France
| | - François Boudet-Devaud
- INSERM UMR-S1124, Cellules Souches, Signalisation et Prions, Université Paris Descartes, Paris, France
| | - Anne-Marie Haeberlé
- Cytologie et Cytopathologie Neuronales, Institut des Neurosciences Cellulaires & Intégratives, CNRS UPR 3212, Strasbourg, France
| | - Valérie Demais
- Plateforme Imagerie In Vitro, CNRS UPS-3156, Université de Strasbourg, Strasbourg, France
| | | | - Stanislas Demuth
- Cytologie et Cytopathologie Neuronales, Institut des Neurosciences Cellulaires & Intégratives, CNRS UPR 3212, Strasbourg, France
| | | | - Odile Kellermann
- INSERM UMR-S1124, Cellules Souches, Signalisation et Prions, Université Paris Descartes, Paris, France
| | - Benoit Schneider
- INSERM UMR-S1124, Cellules Souches, Signalisation et Prions, Université Paris Descartes, Paris, France
| | - Nancy J Grant
- Cytologie et Cytopathologie Neuronales, Institut des Neurosciences Cellulaires & Intégratives, CNRS UPR 3212, Strasbourg, France
| | - Yannick Bailly
- Cytologie et Cytopathologie Neuronales, Institut des Neurosciences Cellulaires & Intégratives, CNRS UPR 3212, Strasbourg, France
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Hovland DN, Boyd RB, Butt MT, Engelhardt JA, Moxness MS, Ma MH, Emery MG, Ernst NB, Reed RP, Zeller JR, Gash DM, Masterman DM, Potter BM, Cosenza ME, Lightfoot RM. Six-Month Continuous Intraputamenal Infusion Toxicity Study of Recombinant Methionyl Human Glial Cell Line-Derived Neurotrophic Factor (r-metHuGDNF) in Rhesus Monkeys. Toxicol Pathol 2017. [DOI: 10.1177/01926230701481899a] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Recombinant human glial cell line-derived neurotrophic factor (r-metHuGDNF) is a potent neuronal growth and survival factor that has been considered for clinical use in the treatment of Parkinson’s disease (PD). Here we present results of a 6-month toxicology study in rhesus monkeys conducted to support clinical evaluation of chronic intraputamenal infusion of r-metHuGDNF for PD. Monkeys (6–9/sex/group) were treated with 0 (vehicle), 15, 30, or 100 μg/day r-metHuGDNF by continuous unilateral intraputamenal infusion (150 μl/day flow rate) for 6 months; a subset of animals (2–3/sex/group) underwent a subsequent 3-month treatment-free recovery period. Notable observations included reduced food consumption and body weight at 100 μg/day and meningeal thickening underlying the medulla oblongata and/or overlying various spinal cord segments at 30 and 100 μg/day. In addition, multifocal cerebellar Purkinje cell loss (with associated atrophy of the molecular layer and, in some cases, granule cell loss) was observed in 4 monkeys in the 100-μg/day group. This cerebellar finding has not been observed in previous nonclinical studies evaluating r-metHuGDNF. The small number of affected animals precludes definitive conclusions regarding the pathogenesis of the cerebellar lesion, but the data support an association with r-metHuGDNF treatment.
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Affiliation(s)
| | - Robert B. Boyd
- Northern Biomedical Research, Inc., Muskegon, Michigan 49441
| | - Mark T. Butt
- Pathology Associates, Charles River Laboratories, Frederick, Maryland 21701
| | | | | | - Mark H. Ma
- Amgen Inc., Thousand Oaks, California 91320
| | | | | | - Randall P. Reed
- Northern Biomedical Research, Inc., Muskegon, Michigan 49441
| | | | - Don M. Gash
- Anatomy and Neurobiology, University of Kentucky, Lexington, Kentucky 40536
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Katnik C, Garcia A, Behensky AA, Yasny IE, Shuster AM, Seredenin SB, Petrov AV, Cuevas J. Activation of σ1 and σ2 receptors by afobazole increases glial cell survival and prevents glial cell activation and nitrosative stress after ischemic stroke. J Neurochem 2016; 139:497-509. [PMID: 27488244 DOI: 10.1111/jnc.13756] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2016] [Revised: 07/22/2016] [Accepted: 07/26/2016] [Indexed: 11/30/2022]
Abstract
Activation of sigma receptors at delayed time points has been shown to decrease injury following ischemic stroke. The mixed σ1/σ2 receptor agonist, 5-ethoxy-2-[2-(morpholino)-ethylthio]benzimidazole (afobazole), provides superior long-term outcomes compared to other σ ligands in the rat middle cerebral artery occlusion (MCAO) stroke model. Experiments using the MCAO model were carried out to determine the molecular mechanism involved in the beneficial effects of afobazole. Administration of afobazole (3 mg/kg) at delayed time points post-stroke significantly increased the number of microglia and astrocytes detected in the ipsilateral hemisphere at 96 h post-surgery. Morphological analysis of the microglia indicated that a greater number of these cells were found in the ramified resting state in MCAO animals treated with afobazole relative to MCAO vehicle controls. Similarly, fewer reactive astrocytes were detected in the injured hemisphere of afobazole-treated animals. Both the enhanced survival and reduced activation of glial cells were abolished by co-application of either a σ1 (BD-1063) or a σ2 (SM-21) receptor antagonist with afobazole. To gain further insight into the mechanisms by which afobazole lessens stroke injury, we probed the brain sections for markers of neuroinflammation (tumor necrosis factor α) and nitrosative stress (S-nitrosocysteine). Data show that afobazole significantly reduces S-nitrosocysteine levels, but does not alter tumor necrosis factor α expression 96 h after an ischemic stroke. Taken together our data indicate that afobazole acting via both σ1 and σ2 receptors decreases stroke injury by enhancing glial cell survival, blocking ischemia-induced glial cell activation, and decreasing nitrosative stress.
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Affiliation(s)
- Christopher Katnik
- Department of Molecular Pharmacology and Physiology, Morsani College of Medicine, University of South Florida, Tampa, Florida, USA
| | - Angela Garcia
- Department of Molecular Pharmacology and Physiology, Morsani College of Medicine, University of South Florida, Tampa, Florida, USA
| | - Adam A Behensky
- Department of Molecular Pharmacology and Physiology, Morsani College of Medicine, University of South Florida, Tampa, Florida, USA
| | | | | | | | | | - Javier Cuevas
- Department of Molecular Pharmacology and Physiology, Morsani College of Medicine, University of South Florida, Tampa, Florida, USA.
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Schep LJ, Slaughter RJ, Galea S, Newcombe D. Ibogaine for treating drug dependence. What is a safe dose? Drug Alcohol Depend 2016; 166:1-5. [PMID: 27426011 DOI: 10.1016/j.drugalcdep.2016.07.005] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/12/2016] [Revised: 07/04/2016] [Accepted: 07/04/2016] [Indexed: 11/30/2022]
Abstract
The indole alkaloid ibogaine, present in the root bark of the West African rain forest shrub Tabernanthe iboga, has been adopted in the West as a treatment for drug dependence. Treatment of patients requires large doses of the alkaloid to cause hallucinations, an alleged integral part of the patient's treatment regime. However, case reports and case series continue to describe evidences of ataxia, gastrointestinal distress, ventricular arrhythmias and sudden and unexplained deaths of patients undergoing treatment for drug dependence. High doses of ibogaine act on several classes of neurological receptors and transporters to achieve pharmacological responses associated with drug aversion; limited toxicology research suggests that intraperitoneal doses used to successfully treat rodents, for example, have also been shown to cause neuronal injury (purkinje cells) in the rat cerebellum. Limited research suggests lethality in rodents by the oral route can be achieved at approximately 263mg/kg body weight. To consider an appropriate and safe initial dose for humans, necessary safety factors need to be applied to the animal data; these would include factors such as intra- and inter-species variability and for susceptible people in a population (such as drug users). A calculated initial dose to treat patients could be approximated at 0.87mg/kg body weight, substantially lower than those presently being administered to treat drug users. Morbidities and mortalities will continue to occur unless practitioners reconsider doses being administered to their susceptible patients.
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Affiliation(s)
- L J Schep
- National Poisons Centre, Department of Preventive and Social Medicine, University of Otago, Dunedin, New Zealand.
| | - R J Slaughter
- National Poisons Centre, Department of Preventive and Social Medicine, University of Otago, Dunedin, New Zealand
| | - S Galea
- Community Alcohol and Drug Services, Waitemata DHB, New Zealand; Social and Community Health and Centre for Addiction Research, University of Auckland, New Zealand
| | - D Newcombe
- Social and Community Health and Centre for Addiction Research, University of Auckland, New Zealand
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Hovland DN, Boyd RB, Butt MT, Engelhardt JA, Moxness MS, Ma MH, Emery MG, Ernst NB, Reed RP, Zeller JR, Gash DM, Masterman DM, Potter BM, Cosenza ME, Lightfoot RM. Reprint: Six-Month Continuous Intraputamenal Infusion Toxicity Study of Recombinant Methionyl Human Glial Cell Line-Derived Neurotrophic Factor (r-metHuGDNF) in Rhesus Monkeys. Toxicol Pathol 2016; 35:1013-29. [PMID: 18098052 DOI: 10.1177/01926230701481899] [Citation(s) in RCA: 50] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Recombinant human glial cell line-derived neurotrophic factor (r-metHuGDNF) is a potent neuronal growth and survival factor that has been considered for clinical use in the treatment of Parkinson’s disease (PD). Here we present results of a 6-month toxicology study in rhesus monkeys conducted to support clinical evaluation of chronic intraputamenal infusion of r-metHuGDNF for PD. Monkeys (6–9/sex/group) were treated with 0 (vehicle), 15, 30, or 100 μg/day r-metHuGDNF by continuous unilateral intraputamenal infusion (150 μl/day flow rate) for 6 months; a subset of animals (2–3/sex/group) underwent a subsequent 3-month treatment-free recovery period. Notable observations included reduced food consumption and body weight at 100 μg/day and meningeal thickening underlying the medulla oblongata and/or overlying various spinal cord segments at 30 and 100 μg/day. In addition, multifocal cerebellar Purkinje cell loss (with associated atrophy of the molecular layer and, in some cases, granule cell loss) was observed in 4 monkeys in the 100-μg/day group. This cerebellar finding has not been observed in previous nonclinical studies evaluating r-metHuGDNF. The small number of affected animals precludes definitive conclusions regarding the pathogenesis of the cerebellar lesion, but the data support an association with r-metHuGDNF treatment.
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Affiliation(s)
| | - Robert B. Boyd
- Northern Biomedical Research, Inc., Muskegon, Michigan 49441
| | - Mark T. Butt
- Pathology Associates, Charles River Laboratories, Frederick, Maryland 21701
| | | | | | - Mark H. Ma
- Amgen Inc., Thousand Oaks, California 91320
| | | | | | - Randall P. Reed
- Northern Biomedical Research, Inc., Muskegon, Michigan 49441
| | | | - Don M. Gash
- Anatomy and Neurobiology, University of Kentucky, Lexington, Kentucky 40536
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Ibogaine and addiction in the animal model, a systematic review and meta-analysis. Transl Psychiatry 2016; 6:e826. [PMID: 27244235 PMCID: PMC5545647 DOI: 10.1038/tp.2016.71] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/08/2015] [Revised: 03/04/2016] [Accepted: 03/17/2016] [Indexed: 02/07/2023] Open
Abstract
Ibogaine is a naturally occurring substance which has been increasingly used in the lay-scene to reduce craving and relapse in patients with substance use disorders (SUDs). Although human clinical trials on the safety and efficacy of ibogaine are lacking, animal studies do support the efficacy of ibogaine. In this systematic review and meta-analysis (MA), we summarise these animal findings, addressing three questions: (1) does ibogaine reduce addictive behaviour in animal models of SUDs?; (2) what are the toxic effects of ibogaine on motor functioning, cerebellum and heart rhythm?; (3) what are neuropharmacological working mechanisms of ibogaine treatment in animal models of SUDs? MA of 27 studies showed that ibogaine reduced drug self-administration, particularly during the first 24 h after administration. Ibogaine had no effect on drug-induced conditioned place preference. Ibogaine administration resulted in motor impairment in the first 24 h after supplementation, and cerebral cell loss even weeks after administration. Data on ibogaines effect on cardiac rhythm, as well as on its neuropharmacological working mechanisms are limited. Our results warrant further studies into the clinical efficacy of ibogaine in SUD patients in reducing craving and substance use, but close monitoring of the patients is recommended because of the possible toxic effects. In addition, more work is needed to unravel the neuropharmacological working mechanisms of ibogaine and to investigate its effects on heart rhythm.
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38
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GDNF-induced cerebellar toxicity: A brief review. Neurotoxicology 2015; 52:46-56. [PMID: 26535469 DOI: 10.1016/j.neuro.2015.10.011] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2015] [Revised: 09/22/2015] [Accepted: 10/24/2015] [Indexed: 12/19/2022]
Abstract
Recombinant-methionyl human glial cell line-derived neurotrophic factor (GDNF) is known for its neurorestorative and neuroprotective effects in rodent and primate models of Parkinson's disease (PD). When administered locally into the putamen of Parkinsonian subjects, early clinical studies showed its potential promise as a disease-modifying agent. However, the development of GDNF for the treatment of PD has been significantly clouded by findings of cerebellar toxicity after continuous intraputamenal high-dose administration in a 6-month treatment/3-month recovery toxicology study in rhesus monkeys. Specifically, multifocal cerebellar Purkinje cell loss affecting 1-21% of the cerebellar cortex was observed in 4 of 15 (26.7%; 95% confidence interval [CI]: 10.5-52.4%) animals treated at the highest dose level tested (3000μg/month). No cerebellar toxicity was observed at lower doses (450 and 900μg/month) in the same study, or at similar or higher doses (up to 10,000μg/month) in subchronic or chronic toxicology studies testing intermittent intracerebroventricular administration. While seemingly associated with the use of GDNF, the pathogenesis of the cerebellar lesions has not been fully understood to date. This review integrates available information to evaluate potential pathogenic mechanisms and provide a consolidated assessment of the findings. While other explanations are considered, the existing evidence is most consistent with the hypothesis that leakage of GDNF into cerebrospinal fluid during chronic infusions into the putamen down-regulates GDNF receptors on Purkinje cells, and that subsequent acute withdrawal of GDNF generates the observed lesions. The implications of these findings for clinical studies with GDNF are discussed.
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Koenig X, Hilber K. The anti-addiction drug ibogaine and the heart: a delicate relation. Molecules 2015; 20:2208-28. [PMID: 25642835 PMCID: PMC4382526 DOI: 10.3390/molecules20022208] [Citation(s) in RCA: 58] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2014] [Revised: 11/11/2014] [Accepted: 11/26/2014] [Indexed: 12/13/2022] Open
Abstract
The plant indole alkaloid ibogaine has shown promising anti-addictive properties in animal studies. Ibogaine is also anti-addictive in humans as the drug alleviates drug craving and impedes relapse of drug use. Although not licensed as therapeutic drug and despite safety concerns, ibogaine is currently used as an anti-addiction medication in alternative medicine in dozens of clinics worldwide. In recent years, alarming reports of life-threatening complications and sudden death cases, temporally associated with the administration of ibogaine, have been accumulating. These adverse reactions were hypothesised to be associated with ibogaine’s propensity to induce cardiac arrhythmias. The aim of this review is to recapitulate the current knowledge about ibogaine’s effects on the heart and the cardiovascular system, and to assess the cardiac risks associated with the use of this drug in anti- addiction therapy. The actions of 18-methoxycoronaridine (18-MC), a less toxic ibogaine congener with anti-addictive properties, are also considered.
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Affiliation(s)
- Xaver Koenig
- Department of Neurophysiology and Neuropharmacology, Center for Physiology and Pharmacology, Medical University of Vienna, Schwarzspanierstrasse 17, Vienna 1090, Austria.
| | - Karlheinz Hilber
- Department of Neurophysiology and Neuropharmacology, Center for Physiology and Pharmacology, Medical University of Vienna, Schwarzspanierstrasse 17, Vienna 1090, Austria.
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Banerjee TS, Paul S, Sinha S, Das S. Synthesis of iboga-like isoquinuclidines: Dual opioid receptors agonists having antinociceptive properties. Bioorg Med Chem 2014; 22:6062-70. [PMID: 25281271 DOI: 10.1016/j.bmc.2014.09.001] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2014] [Revised: 08/25/2014] [Accepted: 09/01/2014] [Indexed: 11/29/2022]
Abstract
Some novel iboga-analogues consisting of benzofuran moiety and dehydroisoquinuclidine ring connected by -CH2-, (CH2)2 and (CH2)3 linkers have been synthesized with the view to develop potential antinociceptive drugs. The compounds 14 and 21 showed binding at the μ-opioid receptor (MOR), while the compound 11a exhibited dual affinities at both MOR and κ-opioid receptor (KOR). MAP kinase activation indicated all three compounds have opioid agonistic properties. The presence of a double bond and endo-methylcarboxylate group in the dehydroisoquinuclidine ring and the benzofuran and methylene spacer appeared to be essential for opioid receptor binding. Further studies demonstrated 11a caused significant antinociception in mice in the hot-plate test which was comparable to that produced by morphine. The compound 11a was also found to be nontremorigenic unlike various iboga congeners. This study identifies a new pharmacophore which may lead to the development of suitable substitute of morphine in the treatment of pain.
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Affiliation(s)
- Tuhin Suvro Banerjee
- Neurobiology Department, CSIR-Indian Institute of Chemical Biology, Jadavpur, Kolkata 700032, India
| | - Sibasish Paul
- Department of Organic Chemistry, Indian Association for the Cultivation of Science, Jadavpur, Kolkata 700032, India
| | - Surajit Sinha
- Department of Organic Chemistry, Indian Association for the Cultivation of Science, Jadavpur, Kolkata 700032, India.
| | - Sumantra Das
- Neurobiology Department, CSIR-Indian Institute of Chemical Biology, Jadavpur, Kolkata 700032, India.
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42
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Schmouth JF, Dion PA, Rouleau GA. Genetics of essential tremor: From phenotype to genes, insights from both human and mouse studies. Prog Neurobiol 2014; 119-120:1-19. [DOI: 10.1016/j.pneurobio.2014.05.001] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2014] [Revised: 04/16/2014] [Accepted: 05/02/2014] [Indexed: 11/30/2022]
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Effect of coadministration of neurovite and Lamivudine on the histomorphology of the cerebellum of wistar rats. ISRN NEUROSCIENCE 2014; 2014:258040. [PMID: 24967314 PMCID: PMC4045568 DOI: 10.1155/2014/258040] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/10/2013] [Accepted: 12/11/2013] [Indexed: 11/18/2022]
Abstract
Introduction. Lamivudine is a nucleoside reverse transcriptase inhibitor antiretroviral agent used in the treatment of human immunodeficiency virus type 1 infection. This study was to investigate the effects of coadministration of neurovite and lamivudine on the histomorphology of the cerebellum of Wistar rats. Materials and Methods. Twenty Wistar rats were divided equally into four groups. Group A animals were the control treated with distilled water. Groups B, C, and D animals were treated, respectively, with therapeutic dose of lamivudine (4.28 mg/kg), a combination of lamivudine (4.28 mg/kg) and neurovite (7.05 mg/kg), and neurovite (7.05 mg/kg) alone, daily. The rats were sacrificed using chloroform inhalation, processed, and stained using H&E method. Results. There was severe cellular degeneration with dystrophic changes, vacuolization in the molecular and granular layers, and aggregation of swollen Purkinje cells in group B animals compared with group C animals which showed only slight cellular dystrophy and inflammation. The mean cellular population was significantly (P < 0.05) higher in the treatment groups compared with the control. Conclusion. There was amelioration of damage of the cerebellum in the animals treated with neurovite and lamivudine combination compared to animals treated with only lamivudine. Therefore, there is need to give neurovite to patients on lamivudine therapy.
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A dihydro-pyrido-indole potently inhibits HSV-1 infection by interfering the viral immediate early transcriptional events. Antiviral Res 2014; 105:126-34. [PMID: 24576908 DOI: 10.1016/j.antiviral.2014.02.007] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2013] [Revised: 02/10/2014] [Accepted: 02/11/2014] [Indexed: 11/23/2022]
Abstract
In our continued quest for identifying novel molecules from ethnomedicinal source we have isolated an alkaloid 7-methoxy-1-methyl-4,9-dihydro-3H-pyrido[3,4-b]indole, also known as Harmaline (HM), from an ethnomedicinal herb Ophiorrhiza nicobarica. The compound exhibited a potent anti-HSV-1 activity against both wild type and clinical isolates of HSV-1. Further we demonstrated that HM did not interfere in viral entry but the recruitment of lysine-specific demethylase-1 (LSD1) and the binding of immediate-early (IE) complex on ICP0 promoter. This leads to the suppression of viral IE gene synthesis and thereby the reduced expression of ICP4 and ICP27. Moreover, HM at its virucidal concentration is nontoxic and reduced virus yields in cutaneously infected Balb/C mice. Thus, the interference in the binding of IE complex, a decisive factor for HSV lytic cycle or latency by HM reveals an interesting target for developing non-nucleotide antiherpetic agent with different mode of action than Acyclovir.
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45
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Affiliation(s)
| | - Richard Hawkes
- Department of Cell Biology and Anatomy, Genes and Development Research Group and Hotchkiss Brain Institute, Faculty of Medicine, University of Calgary
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46
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Koenig X, Kovar M, Rubi L, Mike AK, Lukacs P, Gawali VS, Todt H, Hilber K, Sandtner W. Anti-addiction drug ibogaine inhibits voltage-gated ionic currents: a study to assess the drug's cardiac ion channel profile. Toxicol Appl Pharmacol 2013; 273:259-68. [PMID: 23707769 PMCID: PMC3853361 DOI: 10.1016/j.taap.2013.05.012] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2012] [Revised: 05/02/2013] [Accepted: 05/04/2013] [Indexed: 01/15/2023]
Abstract
The plant alkaloid ibogaine has promising anti-addictive properties. Albeit not licensed as a therapeutic drug, and despite hints that ibogaine may perturb the heart rhythm, this alkaloid is used to treat drug addicts. We have recently reported that ibogaine inhibits human ERG (hERG) potassium channels at concentrations similar to the drugs affinity for several of its known brain targets. Thereby the drug may disturb the heart's electrophysiology. Here, to assess the drug's cardiac ion channel profile in more detail, we studied the effects of ibogaine and its congener 18-Methoxycoronaridine (18-MC) on various cardiac voltage-gated ion channels. We confirmed that heterologously expressed hERG currents are reduced by ibogaine in low micromolar concentrations. Moreover, at higher concentrations, the drug also reduced human Nav1.5 sodium and Cav1.2 calcium currents. Ion currents were as well reduced by 18-MC, yet with diminished potency. Unexpectedly, although blocking hERG channels, ibogaine did not prolong the action potential (AP) in guinea pig cardiomyocytes at low micromolar concentrations. Higher concentrations (≥ 10 μM) even shortened the AP. These findings can be explained by the drug's calcium channel inhibition, which counteracts the AP-prolonging effect generated by hERG blockade. Implementation of ibogaine's inhibitory effects on human ion channels in a computer model of a ventricular cardiomyocyte, on the other hand, suggested that ibogaine does prolong the AP in the human heart. We conclude that therapeutic concentrations of ibogaine have the propensity to prolong the QT interval of the electrocardiogram in humans. In some cases this may lead to cardiac arrhythmias.
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Affiliation(s)
- Xaver Koenig
- Center for Physiology and Pharmacology, Department of Neurophysiology and -pharmacology, Medical University of Vienna, 1090 Vienna, Austria
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Guimarães dos Santos R. Safety and Side Effects of Ayahuasca in Humans—An Overview Focusing on Developmental Toxicology. J Psychoactive Drugs 2013; 45:68-78. [DOI: 10.1080/02791072.2013.763564] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
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Reeber SL, White JJ, George-Jones NA, Sillitoe RV. Architecture and development of olivocerebellar circuit topography. Front Neural Circuits 2013; 6:115. [PMID: 23293588 PMCID: PMC3534185 DOI: 10.3389/fncir.2012.00115] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2012] [Accepted: 12/12/2012] [Indexed: 11/21/2022] Open
Abstract
The cerebellum has a simple tri-laminar structure that is comprised of relatively few cell types. Yet, its internal micro-circuitry is anatomically, biochemically, and functionally complex. The most striking feature of cerebellar circuit complexity is its compartmentalized topography. Each cell type within the cerebellar cortex is organized into an exquisite map; molecular expression patterns, dendrite projections, and axon terminal fields divide the medial-lateral axis of the cerebellum into topographic sagittal zones. Here, we discuss the mechanisms that establish zones and highlight how gene expression and neural activity contribute to cerebellar pattern formation. We focus on the olivocerebellar system because its developmental mechanisms are becoming clear, its topographic termination patterns are very precise, and its contribution to zonal function is debated. This review deconstructs the architecture and development of the olivocerebellar pathway to provide an update on how brain circuit maps form and function.
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Affiliation(s)
- Stacey L Reeber
- Department of Pathology and Immunology, Baylor College of Medicine, Jan and Dan Duncan Neurological Research Institute of Texas Children's Hospital Houston, TX, USA ; Department of Neuroscience, Baylor College of Medicine, Jan and Dan Duncan Neurological Research Institute of Texas Children's Hospital Houston, TX, USA
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Rahimi Shourmasti F, Goudarzi I, Lashkarbolouki T, Abrari K, Elahdadi Salmani M, Goudarzi A. Effects of riluzole on harmaline induced tremor and ataxia in rats: Biochemical, histological and behavioral studies. Eur J Pharmacol 2012; 695:40-7. [DOI: 10.1016/j.ejphar.2012.08.014] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2012] [Revised: 08/26/2012] [Accepted: 08/27/2012] [Indexed: 11/30/2022]
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Handforth A. Harmaline tremor: underlying mechanisms in a potential animal model of essential tremor. TREMOR AND OTHER HYPERKINETIC MOVEMENTS (NEW YORK, N.Y.) 2012; 2. [PMID: 23440018 PMCID: PMC3572699 DOI: 10.7916/d8td9w2p] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/13/2012] [Accepted: 03/24/2012] [Indexed: 01/18/2023]
Abstract
BACKGROUND Harmaline and harmine are tremorigenic β-carbolines that, on administration to experimental animals, induce an acute postural and kinetic tremor of axial and truncal musculature. This drug-induced action tremor has been proposed as a model of essential tremor. Here we review what is known about harmaline tremor. METHODS Using the terms harmaline and harmine on PubMed, we searched for papers describing the effects of these β-carbolines on mammalian tissue, animals, or humans. RESULTS Investigations over four decades have shown that harmaline induces rhythmic burst-firing activity in the medial and dorsal accessory inferior olivary nuclei that is transmitted via climbing fibers to Purkinje cells and to the deep cerebellar nuclei, then to brainstem and spinal cord motoneurons. The critical structures required for tremor expression are the inferior olive, climbing fibers, and the deep cerebellar nuclei; Purkinje cells are not required. Enhanced synaptic norepinephrine or blockade of ionic glutamate receptors suppresses tremor, whereas enhanced synaptic serotonin exacerbates tremor. Benzodiazepines and muscimol suppress tremor. Alcohol suppresses harmaline tremor but exacerbates harmaline-associated neural damage. Recent investigations on the mechanism of harmaline tremor have focused on the T-type calcium channel. DISCUSSION Like essential tremor, harmaline tremor involves the cerebellum, and classic medications for essential tremor have been found to suppress harmaline tremor, leading to utilization of the harmaline model for preclinical testing of antitremor drugs. Limitations are that the model is acute, unlike essential tremor, and only approximately half of the drugs reported to suppress harmaline tremor are subsequently found to suppress tremor in clinical trials.
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Affiliation(s)
- Adrian Handforth
- Neurology Service, Veterans Affairs Greater Los Angeles Healthcare System, Los Angeles, California, United States of America
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