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1.
Neurotoxicology ; 89: 79-91, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34999156

RESUMO

Several Apocynaceae species, most notably Tabernanthe iboga, Voacanga africana and many Tabernaemontana species, produce ibogan-type alkaloids. Although a large amount of information exists about the Tabernaemontana genus, knowledge concerning chemistry and biological activity remains lacking for several species, especially related to their effects on the central nervous system (CNS). The aim of this study was to evaluate the effect of Tabernaemontana arborea Rose ex J.D.Sm. (T. arborea) hydroalcoholic extract (30, 56.2 and 100 mg/kg, i.p.) and two of its main alkaloids (ibogaine and voacangine, 30 mg/kg, i.p.) on electroencephalographic (EEG) activity alone and in the presence of the chemical convulsant agent pentylenetetrazole (PTZ, 85 mg/kg, i.p.) in mice. EEG spectral power analysis showed that T. arborea extract (56.2 and 100 mg/kg) and ibogaine (30 mg/kg, i.p.) promoted a significant increase in the relative power of the delta band and a significant reduction in alpha band values, denoting a CNS depressant effect. Voacangine (30 mg/kg, i.p.) provoked an EEG flattening pattern. The PTZ-induced seizures were not modified in the presence of T. arborea, ibogaine, or voacangine. However, sudden death was observed in mice treated with T. arborea extract at 100 mg/kg, i.p., combined with PTZ. Because T. arborea extract (100 mg/kg, i.p.) and ibogaine (30 mg/kg, i.p.), but not voacangine (30 mg/kg, i.p.), induced paroxysmal activity in the EEG, both were explored in the presence of a serotonin 5-HT1A receptor antagonist (WAY100635, 1 mg/kg, i.p.). The antagonist abolished the paroxysmal activity provoked by T. arborea (100 mg/kg, i.p.) but not that observed with ibogaine, corroborating the participation of serotonin neurotransmission in the T. arborea effects. In conclusion, high doses of the T. arborea extract induced abnormal EEG activity due in part to the presence of ibogaine and involving serotonin 5-HT1A receptor participation. Nevertheless, other possible constituents and mechanisms might participate in this complex excitatory activity that would be interesting to explore in future studies.


Assuntos
Ibogaína , Tabernaemontana , Animais , Eletroencefalografia , Ibogaína/análise , Ibogaína/farmacologia , Camundongos , Receptor 5-HT1A de Serotonina , Serotonina
2.
Forensic Sci Med Pathol ; 17(1): 126-129, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33433774

RESUMO

Ibogaine is a psychotropic indole alkaloid extracted from the roots of the Tabernanthe iboga shrub from the Apocynaceae family. Depending on the taken dose, it can lead to stimulant effects, euphoria, visual and auditory hallucinations, along with auditory, olfactory, and gustatory synesthesia. In addition to its historical usage in spiritual rituals of African tribes, these days iboga extract presents a prohibited, alternative drug widely used as a part of addiction treatment. Ibogaine used in opioid withdrawal is associated with serious side effects and sudden deaths. Besides its main use as an anti-addiction medication in alternative medicine, in moderate doses (from 100mg to 1g) ibogaine most commonly causes a "trance-like state".In this paper, we report the case of a heroin addict who died suddenly 5-12 hours after oral ingestion of powder labeled Tabernanthe iboga which had been bought online and used in the process of detoxification during an addiction treatment. The man was found dead in a rented apartment, where he was undergoing the addiction treatment.External examination revealed no lesions other than nonspecific injuries on the legs. The autopsy showed congestion of internal organs and pulmonary edema. Histopathological analysis of the heart showed neither macroscopic nor microscopic abnormalities. The concentration of ibogaine was 3.26mg/L. Moreover, systematic toxicological analyses of biological samples showed the presence of morphine and codeine. These data suggest that death, which occurred unnaturally after initiation of the "treatment", was probably the result of the cardiovascular effects caused by the ibogaine powder.The presented case highlights the worldwide problem of various products being widely available over the internet and the danger associated with consumption thereof.


Assuntos
Alucinógenos/intoxicação , Ibogaína/intoxicação , Adulto , Hidrocarbonetos Aromáticos com Pontes/análise , Evolução Fatal , Alucinógenos/análise , Dependência de Heroína , Humanos , Ibogaína/análogos & derivados , Ibogaína/análise , Alcaloides Indólicos/análise , Masculino
3.
J Am Chem Soc ; 141(33): 12979-12983, 2019 08 21.
Artigo em Inglês | MEDLINE | ID: mdl-31364847

RESUMO

(-)-Ibogaine and (-)-voacangine are plant derived psychoactives that show promise as treatments for opioid addiction. However, these compounds are produced by hard to source plants, making these chemicals difficult for broad-scale use. Here we report the complete biosynthesis of (-)-voacangine, and de-esterified voacangine, which is converted to (-)-ibogaine by heating, enabling biocatalytic production of these compounds. Notably, (-)-ibogaine and (-)-voacangine are of the opposite enantiomeric configuration compared to the other major alkaloids found in this natural product class. Therefore, this discovery provides insight into enantioselective enzymatic formal Diels-Alder reactions.


Assuntos
Ibogaína/análogos & derivados , Ibogaína/metabolismo , Psicotrópicos/metabolismo , Tabernaemontana/metabolismo , Vias Biossintéticas , Humanos , Ibogaína/análise , Transtornos Relacionados ao Uso de Opioides/tratamento farmacológico , Psicotrópicos/análise , Estereoisomerismo , Tabernaemontana/química , Tabernaemontana/enzimologia
4.
Chem Biodivers ; 13(12): 1730-1737, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27448833

RESUMO

Tabernaemontana alba and Tabernaemontana arborea are Apocynaceae species used in Mexican traditional medicine for which little phytochemical information exists. In this study, preliminary gas chromatography/mass spectrometry analyses of different organs obtained from wild plants of both species identified a total of 10 monoterpenoid indole alkaloids (MIAs) and one simple indole alkaloid, nine of which were reported for the first time in these species. Furthermore, callus cultures were established from T. alba leaf explants and regeneration of whole plants was accomplished via somatic embryogenesis. The anti-addictive MIAs ibogaine and voacangine were then quantified by gas chromatography with flame ionization detection in wild plants of both species, as well as greenhouse-grown plants, in vitro-grown plantlets and embryogenic callus of T. alba. Ibogaine and voacangine were present in most samples taken from the whole plants of both species, with stem and root barks showing the highest concentrations. No alkaloids were detected in callus samples. It was concluded that T. alba and T. arborea are potentially viable sources of ibogaine and voacangine, and that these MIAs can be produced through somatic embryogenesis and whole plant regeneration of T. alba. Approaches to increase MIA yields in whole plants and to achieve alkaloid production directly in cell cultures are discussed.


Assuntos
Ibogaína/análogos & derivados , Ibogaína/análise , Tabernaemontana/química , Ibogaína/biossíntese , México , Especificidade da Espécie
5.
J Clin Pharmacol ; 55(6): 680-7, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25651476

RESUMO

Conversion of ibogaine to its active metabolite noribogaine appears to be mediated primarily by CYP2D6. We compared 168 hours pharmacokinetic profiles of both analytes after a single oral 20 mg dose of ibogaine in 21 healthy subjects who had been pretreated for 6 days with placebo or the CYP2D6 inhibitor paroxetine. In placebo-pretreated subjects, ibogaine was rapidly converted to noribogaine. Median peak noribogaine concentrations occurred at 4 hours. Compared with placebo-pretreated subjects, paroxetine-pretreated subjects had rapid (Tmax = 1.5 hours) and substantial absorption of ibogaine, with detectable levels out to 72 hours, and an elimination half-life of 10.2 hours. In this group, ibogaine was also rapidly converted to noribogaine with a median Tmax of 3 hours. Extent of noribogaine exposure was similar in both groups. CYP2D6 phenotype was robustly correlated with ibogaine AUC0-t (r = 0.82) and Cmax (r = 0.77). Active moiety (ibogaine plus noribogaine) exposure was ∼2-fold higher in paroxetine-pretreated subjects. Single 20 mg ibogaine doses were safe and well tolerated in all subjects. The doubling of exposure to active moiety in subjects with reduced CYP2D6 activity suggests it may be prudent to genotype patients awaiting ibogaine treatment, and to at least halve the intended dose of ibogaine in CYP2D6 poor metabolizers.


Assuntos
Citocromo P-450 CYP2D6/metabolismo , Voluntários Saudáveis , Ibogaína/análogos & derivados , Ibogaína/farmacocinética , Paroxetina/farmacocinética , Adulto , Inibidores do Citocromo P-450 CYP2D6/farmacocinética , Relação Dose-Resposta a Droga , Interações Medicamentosas , Antagonistas de Aminoácidos Excitatórios/farmacocinética , Feminino , Meia-Vida , Humanos , Ibogaína/administração & dosagem , Ibogaína/análise , Ibogaína/metabolismo , Masculino , Paroxetina/administração & dosagem , Fatores de Tempo , Adulto Jovem
6.
J Forensic Sci ; 58(6): 1666-72, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23919354

RESUMO

We report the case of a man who died twelve hours after ingesting powdered iboga root, commonly taken for its stimulant and hallucinogenic properties. Ibogaine and ibogamine were quantified in the powder ingested and the victim's body fluids by GC-MS/MS after liquid-liquid extraction (Toxi-tubes A(®)). The concentrations of ibogaine measured in the blood samples taken at the scene and in the peripheral blood, urine, and gastric fluid samples taken during the autopsy were 0.65, 1.27, 1.7, and 53.5 µg/mL, while the iboga content in the powder was 7.2%. Moreover, systematic toxicological analyses of biological samples showed the presence of diazepam and methadone in therapeutic concentrations. Death was attributed to the ingestion of a substantial quantity of iboga in the context of simultaneous methadone and diazepam consumption.


Assuntos
Hidrocarbonetos Aromáticos com Pontes/análise , Alucinógenos/análise , Alucinógenos/intoxicação , Ibogaína/análise , Tabernaemontana/intoxicação , Adulto , Hidrocarbonetos Aromáticos com Pontes/química , Hidrocarbonetos Aromáticos com Pontes/intoxicação , Diazepam/análise , Toxicologia Forense , Cromatografia Gasosa-Espectrometria de Massas , Conteúdo Gastrointestinal/química , Humanos , Hipnóticos e Sedativos/análise , Ibogaína/química , Ibogaína/intoxicação , Masculino , Metadona/análise , Estrutura Molecular , Entorpecentes/análise , Tratamento de Substituição de Opiáceos , Raízes de Plantas/química , Pós
7.
J Ethnopharmacol ; 140(2): 398-404, 2012 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-22313627

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Bacterial infections remain a significant threat to human health. Due to the emergence of widespread antibiotic resistance, development of novel antibiotics is required in order to ensure that effective treatment remains available. There are several reports on the ethnomedical use of Tabernaemontana elegans pertaining to antibacterial activity. AIM OF THE STUDY: The aim of this study was to isolate and identify the fraction responsible for the antimicrobial activity in Tabernaemontana elegans (Stapf.) root extracts. MATERIALS AND METHODS: The active fraction was characterized by thin layer chromatography (TLC) and gas chromatography-mass spectrometry (GC-MS). Antibacterial activity was determined using the broth micro-dilution assay and antimycobacterial activity using the BACTEC radiometric assay. Cytotoxicity of the crude extract and fractions was assessed against primary cell cultures; lymphocytes and fibroblasts; as well as a hepatocarcinoma (HepG2) and macrophage (THP-1) cell line using the Neutral Red uptake and MTT assays. RESULTS: The crude root extracts were found to contain a high concentration of alkaloids (1.2%, w/w). GC-MS analysis identified the indole alkaloids, voacangine and dregamine, as major components. Antibacterial activity was limited to the Gram-positive bacteria and Mycobacterium species, with MIC values in the range of 64-256µg/ml. When combined with antibiotics, additive antibacterial effects were observed. Marked cytotoxicity to all cell lines tested was evident in the MTT and Neutral Red uptake assays, with IC(50) values <9.81µg/ml. CONCLUSIONS: This study confirms the antibacterial activity of Tabernaemontana elegans and supports its potential for being investigated further for the development of a novel antibacterial compound.


Assuntos
Antibacterianos/farmacologia , Bactérias Gram-Positivas/efeitos dos fármacos , Alcaloides Indólicos/farmacologia , Mycobacterium/efeitos dos fármacos , Extratos Vegetais/farmacologia , Tabernaemontana/química , Antibacterianos/análise , Linhagem Celular , Cromatografia em Camada Fina , Fibroblastos/efeitos dos fármacos , Cromatografia Gasosa-Espectrometria de Massas , Células Hep G2 , Humanos , Ibogaína/análogos & derivados , Ibogaína/análise , Ibogaína/farmacologia , Alcaloides Indólicos/análise , Concentração Inibidora 50 , Linfócitos/efeitos dos fármacos , Macrófagos/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Extratos Vegetais/química , Raízes de Plantas
8.
Hum Exp Toxicol ; 27(3): 181-94, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18650249

RESUMO

Ibogaine is an indole alkaloid derived from the bark of the root of the African shrub Tabernanthe iboga. Psychoactive properties of ibogaine have been known for decades. More recently, based on experimental data from animals and anectodal reports in human, it has been found that this drug has anti-addictive effects. Several patents were published between 1969 and 1995. The pharmacology of ibogaine is quite complex, affecting many different neurotransmitter systems simultaneously. However, the pharmacological targets underlying the physiological and psychological actions of ibogaine are not completely understood. Ibogaine is rapidly metabolized in the body in noribogaine. The purpose of this article was to review data from the literature concerning physicochemical properties, bio-analytical methods, and pharmacology of ibogaine; this article will be focused on the use of this drug as anti-addictive agent.


Assuntos
Ibogaína/farmacologia , Transtornos Relacionados ao Uso de Substâncias/tratamento farmacológico , Animais , Química Farmacêutica , Humanos , Ibogaína/análise , Ibogaína/química , Ibogaína/farmacocinética
9.
Forensic Sci Int ; 176(1): 58-66, 2008 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-18024037

RESUMO

Tabernanthe iboga belongs to the Apocynaceae family. In this study, we report the case of a 37-year-old black male working as a security agent in Paris and found dead naked on the beach in Gabon after consumption of iboga. Autopsy revealed a drowning fatality and a myocardial abnormality (myocardial bridging). Samples of blood, urine, bile, gastric content, liver, lungs, vitreous, spleen and hair were taken. Biological fluids were liquid-liquid extracted with saturated NH4Cl pH 9.5 and methylene chloride/isopropanol (95/5, v/v) in presence of clonazepam-d(4), used as internal standard. After decontamination with dichloromethane, hair was cut into small pieces then sonicated for 2h in saturated NH4Cl pH 9.5 before extraction by methylene chloride/isopropanol (95/5, v/v). After evaporation the residues were reconstituted in methanol/ACN/formate buffer pH 3, from which 10 microL were injected into an ODB Uptisphere C(18) column (150 mm x 2.1mm, 5 microm) and eluted with a gradient of acetonitrile and formate buffer delivered at a flow rate of 200 microL/min. A Quantum Ultra triple-quadrupole mass spectrometer was used for analyses. Ionization was achieved using electrospray in the positive ionization mode (ESI). For each compound, detection was related to three daughter ions (ibogaine: m/z 311.4-->122.1, 174.1 and 188.1; noribogaine: m/z 297.4-->122.1, 159.1 and 160.1; clonazepam-d(4): m/z 319.9-->218.1, 245.1 and 274.1). Ibogaine and noribogaine were detected in all autopsy samples. Hair segmentation was not possible as hair was very short and frizzy. Concentrations of 1.2 and 2.5 ng/mg, respectively were detected. Neither other licit or illicit drugs nor alcohol were found. The presence of ibogaine and noribogaine in all autopsy samples was consistent with the recent absorption of Tabernanthe iboga, which was assumed to be responsible of the drowning fatality. The history of exposure, regarding hair analysis, is discussed. LC-MS/MS appears to be the best method for analyzing complex and poorly volatile alkaloids in autopsy samples and particularly in hair, due to the presence of a nitrogen ring and the relatively low concentrations to be measured.


Assuntos
Cabelo/química , Alucinógenos/análise , Ibogaína/análogos & derivados , Ibogaína/análise , Tabernaemontana/efeitos adversos , Adulto , Afogamento , Cromatografia Gasosa-Espectrometria de Massas , Alucinógenos/química , Humanos , Ibogaína/química , Masculino , Estrutura Molecular , Detecção do Abuso de Substâncias
10.
J Mass Spectrom ; 37(2): 216-22, 2002 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11857766

RESUMO

Four alkaloids were isolated from an alcoholic extract of the bark from the stem of Peschiera fuschiaefolia. Two of these compounds, voacamine and voacamidine, are dimeric alkaloids which are thought to be responsible for the antimalarial activity of these extracts. The mass spectra and the response factors of these four compounds were obtained by liquid chromatography/mass spectrometry in the electrospray positive ionization mode. The concentrations of these alkaloids were measured in two different P. fuschiaefolia extracts. The ion chromatograms of the two extracts were compared on the basis of their [M + H](+) and [M + 2H](+2) ions characteristic of various alkaloids previously isolated from P. fuschiaefolia bark. The two extracts were found to differ mostly in the relative concentrations of the dimeric alkaloids.


Assuntos
Alcaloides/análise , Ibogaína/análogos & derivados , Medicina Tradicional , Extratos Vegetais/química , Tabernaemontana/química , Antimaláricos/análise , Cromatografia Líquida de Alta Pressão , Ibogaína/análise , Reprodutibilidade dos Testes , América do Sul , Espectrometria de Massas por Ionização por Electrospray
11.
Psychopharmacology (Berl) ; 127(1): 10-8, 1996 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-8880938

RESUMO

The purported efficacy of ibogaine for the treatment of drug dependence may be due in part to an active metabolite. Ibogaine undergoes first pass metabolism and is O-demethylated to 12-hydroxyibogamine (12-OH ibogamine). Radioligand binding assays were conducted to identify the potency and selectivity profiles for ibogaine and 12-OH ibogamine. A comparison of 12-OH ibogamine to the primary molecular targets identified previously for ibogaine demonstrates that the metabolite has a binding profile that is similar, but not identical to the parent drug. Both ibogaine and 12-OH ibogamine demonstrated the highest potency values at the cocaine recognition site on the 5-HT transporter. The same rank order (12-OH ibogamine > ibogaine), but lower potencies were observed for the [3H]paroxetine binding sites on the 5-HT transporter. Ibogaine and 12-OH ibogamine were equipotent at vesicular monoamine and dopamine transporters. The metabolite demonstrated higher affinity at the kappa-1 receptor and lower affinity at the NMDA receptor complex compared to the parent drug. Quantitation of the regional brain levels of ibogaine and 12-OH ibogamine demonstrated micromolar concentrations of both the parent drug and metabolite in rat brain. Drug dependence results from distinct, but inter-related neurochemical adaptations, which underlie tolerance, sensitization and withdrawal. Ibogaine's ability to alter drug-seeking behavior may be due to combined actions of the parent drug and metabolite at key pharmacological targets that modulate the activity of drug reward circuits.


Assuntos
Ibogaína/análogos & derivados , Sítios de Ligação , Encéfalo/metabolismo , Tronco Encefálico/química , Cerebelo/química , Córtex Cerebral/química , Corpo Estriado/química , Dopamina/metabolismo , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Ibogaína/análise , Ibogaína/metabolismo , Ibogaína/farmacologia , Ensaio Radioligante , Receptores de N-Metil-D-Aspartato/metabolismo , Serotonina/metabolismo
12.
Biochem Pharmacol ; 49(1): 73-9, 1995 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-7840786

RESUMO

A sensitive and highly selective analytical chemical method for measuring the indole alkaloid ibogaine in biological samples has been developed. The method utilizes organic extraction, derivatization with trifluoroacetic anhydride, and detection by combined gas chromatography-mass spectrometry. The deuterated analog of ibogaine, O-[Cd3]-ibogaine, was synthesized and used as an internal standard for the method. Standard curves, constructed from variable amounts of ibogaine (50-400 ng) and a fixed amount of internal standard (250 ng) were linear. The method has an approximate detection limit of at least 20 ng/mL of tissue extract (180 ng/g tissue), with a coefficient of variation of 8 to 12.5%. Chemical stability studies with the method found that aqueous ibogaine solutions (1-10 mg/mL) could be stored at 10 degrees for up to 7 months with no more than 10% loss. The method was also used to measure brain ibogaine levels in rats 1 and 19 hr after a single dose of drug (40 mg/kg, i.p.); the results suggest a rapid disappearance of the drug after i.p. dosing. The method will help reveal the pharmacokinetic properties of this putative anti-addictive agent in animals and humans.


Assuntos
Ibogaína/análise , Anidridos Acéticos , Animais , Encéfalo/metabolismo , Química Encefálica , Estabilidade de Medicamentos , Feminino , Fluoracetatos , Cromatografia Gasosa-Espectrometria de Massas/métodos , Calefação , Ibogaína/metabolismo , Ratos , Ratos Sprague-Dawley , Padrões de Referência , Sensibilidade e Especificidade
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