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1.
Anal Bioanal Chem ; 416(1): 175-189, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37910202

RESUMO

Consumers have unprecedented access to botanical dietary supplements through online retailers, making it difficult to ensure product quality and authenticity. Therefore, methods to survey and compare chemical compositions across botanical products are needed. Nuclear magnetic resonance (NMR) spectroscopy and non-targeted mass spectrometry (MS) were used to chemically analyze commercial products labeled as containing one of three botanicals: blue cohosh, goldenseal, and yohimbe bark. Aqueous and organic phase extracts were prepared and analyzed in tandem with NMR followed by MS. We processed the non-targeted data using multivariate statistics to analyze the compositional similarity across extracts. In each case, there were several product outliers that were identified using principal component analysis (PCA). Evaluation of select known constituents proved useful to contextualize PCA subgroups, which in some cases supported or refuted product authenticity. The NMR and MS data reached similar conclusions independently but were also complementary.


Assuntos
Produtos Biológicos , Caulophyllum , Hydrastis , Pausinystalia/química , Hydrastis/química , Caulophyllum/química , Casca de Planta/química , Cromatografia Gasosa-Espectrometria de Massas , Espectrometria de Massas/métodos , Espectroscopia de Ressonância Magnética , Produtos Biológicos/análise
2.
J Am Chem Soc ; 146(1): 118-124, 2024 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-38153983

RESUMO

Corynantheine-type alkaloids are major components of the Mitragyna speciosa, also known as kratom, that exhibit unique pharmacological activity. However, no universal method to prepare these alkaloids has been reported. Disclosed herein is a catalytic, asymmetric platform that enables rapid access to corynantheine alkaloids. The first enantioselective total synthesis of (-)-corynantheidine pseudoindoxyl is described. The first asymmetric syntheses of (+)-corynoxine and (-)-corynoxine B were also achieved, along with enantioselective syntheses of (-)-corynantheidol and (-)-corynantheidine. Through this work, all series of corynantheine alkaloids including indole, spirooxindole, and pseudoindoxyl can now be accessed in the laboratory, enabling comprehensive biological investigation of kratom alkaloids to be undertaken.


Assuntos
Benzopiranos , Nitrilas , Pausinystalia , Alcaloides de Triptamina e Secologanina , Compostos de Espiro , Oxindóis , Alcaloides de Triptamina e Secologanina/farmacologia
3.
Sci Rep ; 13(1): 15487, 2023 09 19.
Artigo em Inglês | MEDLINE | ID: mdl-37726357

RESUMO

DNA interactions with multivalent ligand(s) have increasingly become the subject of substantial research. For several small molecules with therapeutic potential, nucleic acids serve as their primary molecular target. Such interaction has been shown to affect transcription or replication, ultimately leading to apoptotic cell death. As a result, researchers are becoming increasingly interested in understanding how small molecules interact with DNA making it possible to develop new, DNA-specific drugs. The bioactive indole alkaloid, Yohimbe (Yohimbine; Yh) has been broadly studied in pharmacological properties while its binding mode to DNA has not been explicated so far. This study adopted molecular modelling and multi-spectroscopic methods to investigate the interaction between Yohimbine and herring testes (HT DNA) in physiological conditions. Minor hypochromic and bathochromic shifts of fluorescence intensity were observed, suggesting the binding of Yh to HT DNA. The Scatchard plot analyses using the McGhee-von Hipple method revealed non-cooperative binding and affinities in the range of 105 M-1. The thermodynamic parameters suggested exothermic binding, which was favoured by negative enthalpy and positive entropy changes from temperature-dependent fluorescence experiments. Salt-dependent fluorescence suggested that the interaction between the ligand and DNA was governed by non-polyelectrolytic forces. The results of iodide quenching, urea denaturation assay, dye displacement, and in silico molecular docking, suggested groove binding of Yh to HT DNA. Thus, the groove binding mechanism of interaction was validated by both biophysical and computational techniques. The structural elucidation and energetic profiling of Yh's interaction with naturally occurring polymeric DNA can be useful to the development of DNA-targeted therapeutics.


Assuntos
DNA , Pausinystalia , Ligantes , Simulação de Acoplamento Molecular , Ioimbina , Polímeros
4.
Phytochemistry ; 213: 113786, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37422009

RESUMO

Medicinal plants constitute a source for designing clinically useful drugs targeting diseases through various mechanisms. Plant secondary metabolites can be used as lead compounds of drugs. Corynanthe alkaloids are highly abundant natural bioactive substances of various core structures possessing important properties such as nerve excitation and antimalarial and analgesic effects. In this review, we summarize and review the state-of-the-art corynanthe-type alkaloid research focusing on phytochemistry, pharmacology, and structural chemistry. Approximately 120 articles reporting 231 alkaloids classified into simple corynanthe, yohimbine, oxindole corynanthe, mavacurane, sarpagine, akuammiline, strychnos, and ajmaline-type groups were compiled. Relevant biological properties discussed include antiviral, antibacterial, anti-inflammatory, antimalarial, muscle-relaxant, vasorelaxant, and analgesic activities and activities affecting the main nervous and cardiac systems, as well as NF-κB inhibitory and Na+-glucose cotransporter inhibitory properties. This review provides insights and a reference for future studies, thus paving the way for the discovery of drugs based on corynanthe alkaloids.


Assuntos
Alcaloides , Antimaláricos , Plantas Medicinais , Pausinystalia , Alcaloides/farmacologia , Analgésicos/farmacologia , Compostos Fitoquímicos/farmacologia , Extratos Vegetais/farmacologia
5.
Molecules ; 25(11)2020 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-32517373

RESUMO

Epicatechocorynantheines A and B, and epicatechocorynantheidine were isolated from the stem bark of Corynanthe pachyceras. These molecules were pinpointed, and their isolation streamlined, by a molecular networking strategy. The structural elucidation was unambiguously accomplished from HRMS and 1D/2D NMR data. These compounds represent the first examples of corynanthean-type alkaloids tethered with a flavonoid. Epicatechocorynantheidine notably instigated two connections between the monoterpene indole alkaloid and the flavonoid, yielding an unprecedented octacyclic appendage. These flavoalkaloids exerted moderate antiplasmodial activities.


Assuntos
Anti-Helmínticos/farmacologia , Catequina/química , Flavonoides/química , Alcaloides Indólicos/química , Concentração Inibidora 50 , Espectroscopia de Ressonância Magnética , Espectrometria de Massas , Estrutura Molecular , Monoterpenos/química , Pausinystalia/química , Casca de Planta/química , Caules de Planta/química
6.
Chin J Nat Med ; 17(12): 918-923, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31882046

RESUMO

Four new corynanthe-type alkaloids, meloslines C-F (1-4), together with four known ones (5-8) were isolated from the roots of Alstonia scholaris. Their structures including absolute configurations were elucidated by extensive spectroscopic analysis and electronic circular dichroism (ECD) calculation. Compounds 1 and 2 exhibited potent vasorelaxant activity on endothelium-intact renal arteries precontracted with KCl.


Assuntos
Alcaloides/isolamento & purificação , Alcaloides/farmacologia , Alstonia/química , Pausinystalia/química , Raízes de Plantas/química , Vasodilatadores/farmacologia , Animais , China , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Ratos Sprague-Dawley , Artéria Renal/efeitos dos fármacos , Vasodilatadores/isolamento & purificação
7.
J Emerg Med ; 57(1): 43-46, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31031073

RESUMO

BACKGROUND: Hypertensive urgency is a clinical scenario that may be associated with herbal supplement use and that requires special consideration with regard to emergency department management. CASE REPORT: A 49-year-old man presented to the emergency department with palpitations and severely elevated blood pressure without evidence of end organ dysfunction. Hypertension failed to be controlled with multiple doses of oral clonidine and intravenous labetalol. The patient later admitted to using an herbal supplement containing yohimbine, a selective ⍺2-adrenoreceptor antagonist specifically linked to cases of refractory hypertension. WHY SHOULD AN EMERGENCY PHYSICIAN BE AWARE OF THIS?: Between 17-35% of the U.S. adult population may use herbal supplements on a sporadic or regular basis; pharmacologically active agents in herbal supplements may affect both a patient's presentation and response to treatment. Most patients do not mention over-the-counter and herbal products in their medication profile unless specifically asked, and therefore it is important for emergency physicians to be aware of the pharmacologic effects of herbal supplements in the evaluation and treatment of refractory severe hypertension.


Assuntos
Pressão Sanguínea/efeitos dos fármacos , Hipertensão/etiologia , Pausinystalia/efeitos adversos , Anti-Hipertensivos/uso terapêutico , Pressão Sanguínea/fisiologia , Clonidina/uso terapêutico , Suplementos Nutricionais/efeitos adversos , Eletrocardiografia/métodos , Serviço Hospitalar de Emergência/organização & administração , Humanos , Labetalol/uso terapêutico , Masculino , Pessoa de Meia-Idade , Pausinystalia/metabolismo
8.
J Cosmet Dermatol ; 18(4): 1037-1043, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30456780

RESUMO

BACKGROUND AND OBJECTIVE: Topical aminophylline, caffeine, yohimbe, l-carnitine, and gotu kola (Centella asiatica) may aid in reducing body fat. Lipoxyderm™ contains these ingredients and was used to test if fat loss of the thigh, in conjunction with a low intensity exercise program and restricted calorie intake, was enhanced via the topical application of this lotion. METHODS: This was a double-blind, placebo-controlled, within-group study that investigated the effects of Lipoxyderm™ on thigh fat mass, circumference, and skinfold thickness. Seven participants underwent pre/post-exercise testing for weight, bilateral thigh circumference/skinfold thickness, and body composition/thigh fat mass assessment via dual-energy X-ray absorptiometry. Participants followed a hypocaloric diet, walked 150 minutes/wk, and were randomly assigned to apply a placebo to one leg and Lipoxyderm™ to their other leg for 28 days. Separate two-way mixed factorial repeated measures ANOVAs were used to compare the effects of Lipoxyderm™ to the placebo on thigh circumference, skinfold thickness, and fat mass. RESULTS: A significant time x group interaction was found for thigh circumference (F1,6  = 18.2, P = 0.005), skinfold thickness (F1,6  = 14.6, P = 0.009), and fat mass (F1,6  = 37.1, P = 0.001). CONCLUSIONS: A twice-daily topical application of Lipoxyderm™ for 28 days compared to a placebo combined with a walking program and a restricted caloric intake is more effective at reducing thigh circumference (1.2 vs 0.8 cm), thigh skinfold thickness (3.7 vs 2.0 mm), and thigh fat mass (100.0 g vs 57.3 g).


Assuntos
Dieta Redutora , Obesidade/prevenção & controle , Comportamento Sedentário , Creme para a Pele/administração & dosagem , Caminhada , Adiposidade/efeitos dos fármacos , Administração Cutânea , Adolescente , Adulto , Aminofilina/administração & dosagem , Cafeína/administração & dosagem , Carnitina/administração & dosagem , Centella/química , Terapia Combinada/métodos , Método Duplo-Cego , Feminino , Humanos , Obesidade/etiologia , Pausinystalia/química , Placebos/administração & dosagem , Extratos Vegetais/administração & dosagem , Creme para a Pele/química , Dobras Cutâneas , Coxa da Perna , Resultado do Tratamento , Adulto Jovem
9.
J Nat Prod ; 81(8): 1841-1849, 2018 08 24.
Artigo em Inglês | MEDLINE | ID: mdl-30059216

RESUMO

Ten new alkaloids (1-10), including two pairs of enantiomeric mixtures (5a,b and 6a,b), and 15 known analogues (11-25) were obtained from the bark of Pausinystalia yohimbe. The structures of 1-25 were established by spectroscopic methods, and the absolute configurations of compounds 1-10 were resolved by X-ray diffraction and ECD data analyses. The in vitro immunosuppressive activities of selected isolates were tested. Compounds 11 and 16 exhibited moderate inhibition with IC50 values of 16.8 and 27.6 µM against ConA-induced T lymphocyte proliferation and 13.5 and 40.5 µM against LPS-induced B lymphocyte proliferation, respectively.


Assuntos
Alcaloides/química , Alcaloides/farmacologia , Imunossupressores/química , Imunossupressores/farmacologia , Pausinystalia/química , Casca de Planta/química , Animais , Linfócitos B/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Dicroísmo Circular , Lipopolissacarídeos/farmacologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Estrutura Molecular , Espectrometria de Massas por Ionização por Electrospray , Linfócitos T/efeitos dos fármacos , Linfócitos T/imunologia , Difração de Raios X
10.
J Diet Suppl ; 15(4): 516-555, 2018 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-28981338

RESUMO

BACKGROUND: The purpose of this review was to create an online research summary table of heart toxicity case reports related to dietary supplements (DS; includes herbs). METHODS: Documented PubMed case reports of DS appearing to contribute to heart-related problems were used to create a "Toxic Table" that summarized the research (1966 to April, 2016, and cross-referencing). Keywords included "herb," "dietary supplement," and cardiac terms. Case reports were excluded if they were herb combinations (some exceptions), Chinese herb mixtures, teas of mixed herb contents, mushrooms, poisonous plants, self-harm (e.g. suicide), excess dose (except vitamins/minerals), drugs or illegal drugs, drug-herbal interactions, and confounders of drugs or diseases. The spectrum of heart toxicities included hypertension, hypotension, hypokalemia, bradycardia, tachycardia, arrhythmia, ventricular fibrillation, heart attack, cardiac arrest, heart failure, and death. RESULTS: Heart related problems were associated with approximately seven herbs: Four traditional Chinese medicine herbs - Don quai (Angelica sinensis), Jin bu huan (Lycopodium serratum), Thundergod vine or lei gong teng (Tripterygium wilfordii Hook F), and Ting kung teng (Erycibe henryi prain); one an Ayruvedic herb - Aswagandha, (Withania somnifera); and two North American herbs - blue cohosh (Caulophyllum thalictroides), and Yohimbe (Pausinystalia johimbe). Aconitum and Ephedra species are no longer sold in the United States. The DS included, but are not limited to five DS - bitter orange, caffeine, certain energy drinks, nitric oxide products, and a calming product. Six additional DS are no longer sold. Licorice was the food related to heart problems. CONCLUSION: The online "Toxic Table" forewarns clinicians, consumers and the DS industry by listing DS with case reports related to heart toxicity. It may also contribute to Phase IV post marketing surveillance to diminish adverse events that Government officials use to regulate DS.


Assuntos
Suplementos Nutricionais/toxicidade , Cardiopatias/induzido quimicamente , Preparações de Plantas/toxicidade , Caulophyllum/toxicidade , Medicamentos de Ervas Chinesas/toxicidade , Humanos , Pausinystalia/toxicidade , Extratos Vegetais/toxicidade , Plantas Medicinais/toxicidade , Estados Unidos , Withania/toxicidade
11.
Artigo em Inglês | MEDLINE | ID: mdl-27092588

RESUMO

In 2013 the Dutch authorities issued a warning against a dietary supplement that was linked to 11 reported adverse reactions, including heart problems and in one case even a cardiac arrest. In the UK a 20-year-old woman, said to have overdosed on this supplement, died. Since according to the label the product was a herbal mixture, initial LC-MS/MS analysis focused on the detection of plant toxins. Yohimbe alkaloids, which are not allowed to be present in herbal preparations according to Dutch legislation, were found at relatively high levels (400-900 mg kg(-1)). However, their presence did not explain the adverse health effects reported. Based on these effects the supplement was screened for the presence of a ß-agonist, using three different biosensor assays, i.e. the validated competitive radioligand ß2-adrenergic receptor binding assay, a validated ß-agonists ELISA and a newly developed multiplex microsphere (bead)-based ß-agonist assay with imaging detection (MAGPIX(®)). The high responses obtained in these three biosensors suggested strongly the presence of a ß-agonist. Inspection of the label indicated the presence of N-isopropyloctopamine. A pure standard of this compound was bought and shown to have a strong activity in the three biosensor assays. Analysis by LC-full-scan high-resolution MS confirmed the presence of this 'unknown known' ß3-agonist N-isopropyloctopamine, reported to lead to heart problems at high doses. A confirmatory quantitative analysis revealed that one dose of the preparation resulted in an intake of 40-60 mg, which is within the therapeutic range of this compound. The case shows the strength of combining bioassays with chemical analytical techniques for identification of illegal pharmacologically active substances in food supplements.


Assuntos
Agonistas de Receptores Adrenérgicos beta 3/envenenamento , Antipirina/análogos & derivados , Depressores do Apetite/efeitos adversos , Suplementos Nutricionais/efeitos adversos , Contaminação de Alimentos , Cardiopatias/etiologia , Preparações de Plantas/efeitos adversos , Agonistas de Receptores Adrenérgicos beta 3/análise , Alcaloides/análise , Alcaloides/toxicidade , Anabolizantes/efeitos adversos , Anabolizantes/química , Anabolizantes/envenenamento , Anabolizantes/normas , Antipirina/análise , Antipirina/envenenamento , Depressores do Apetite/química , Depressores do Apetite/envenenamento , Depressores do Apetite/normas , Técnicas Biossensoriais , Suplementos Nutricionais/análise , Suplementos Nutricionais/envenenamento , Suplementos Nutricionais/normas , Inspeção de Alimentos , Rotulagem de Alimentos , Doenças Transmitidas por Alimentos/etiologia , Doenças Transmitidas por Alimentos/mortalidade , Doenças Transmitidas por Alimentos/terapia , Cardiopatias/mortalidade , Cardiopatias/terapia , Hospitalização , Humanos , Internet , Países Baixos , Nootrópicos/efeitos adversos , Nootrópicos/química , Nootrópicos/envenenamento , Nootrópicos/normas , Pausinystalia/efeitos adversos , Pausinystalia/química , Substâncias para Melhoria do Desempenho/efeitos adversos , Substâncias para Melhoria do Desempenho/química , Substâncias para Melhoria do Desempenho/envenenamento , Substâncias para Melhoria do Desempenho/normas , Preparações de Plantas/química , Preparações de Plantas/envenenamento , Preparações de Plantas/normas
12.
Drug Test Anal ; 8(3-4): 357-69, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26391406

RESUMO

In the USA, botanical dietary supplements are presumed to be safe, but this is not necessarily always the case. Extracts of the evergreen tree yohimbe, Pausinystalia johimbe, though banned in many countries, are sold in hundreds of dietary supplements in the USA. We analyzed 49 brands of supplements labelled as containing yohimbe or yohimbine available for sale from seven major retailers in the USA. Supplements were analyzed using ultra high-performance liquid chromatography coupled to photodiode and quadrupole time-of-flight mass spectrometry detectors for quantity of three alkaloids found in P. johimbe (yohimbine, rauwolscine, and corynanthine). The alkaloids were confirmed on the basis of retention time, ultraviolet spectra, and mass spectra against reference standards. The quantity of the most active alkaloid, yohimbine, per recommended serving ranged from none detected to 12.1 mg. Thirty-nine percent of the supplements (19/49) did not contain rauwolscine and corynanthine suggesting that the yohimbine was either from highly processed plant extract or synthetic in origin. Only 11 supplement brands (22%, 11/49) listed a specific quantity of yohimbine on the label. Most of these were inaccurately labelled (actual content ranged from 23% to 147% of the content on the label). Eighteen percent (9/49) of the supplements' labels did not provide any information about yohimbine's adverse effects. Of the 49 yohimbine supplement brands sold at seven major retail chains in the USA, only 4.1% (2/49) provided consumers with both accurate information about the quantity of yohimbine as well as information about yohimbine's known adverse effects. Copyright © 2015 John Wiley & Sons, Ltd.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Suplementos Nutricionais/análise , Extratos Vegetais/análise , Ioimbina/análise , Suplementos Nutricionais/normas , Espectrometria de Massas/métodos , Pausinystalia/química , Rotulagem de Produtos/normas , Padrões de Referência , Estados Unidos
13.
J AOAC Int ; 98(4): 896-901, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26268969

RESUMO

A single-laboratory validation was performed on a practical ultra-HPLC (UHPLC)-diode array detector (DAD)/tandem MS method for determination of yohimbine in yohimbe barks and related dietary supplements. Good separation was achieved using a Waters Acquity ethylene bridged hybrid C18 column with gradient elution using 0.1% (v/v) aqueous ammonium hydroxide and 0.1% ammonium hydroxide in methanol as the mobile phases. The method can separate corynanthine from yohimbine in yohimbe bark extract, which is critical for accurate quantitation of yohimbine in yohimbe bark and related dietary supplements. Accuracy of the method was demonstrated using standard addition methods. Both intraday and interday precisions of the method were good. The method can be used without MS since yohimbine concentration in yohimbe barks and related dietary supplements are usually high enough for DAD detection, which can make it an easy and economical method for routine analysis of yohimbe barks and related dietary supplements. On the other hand, the method can be used with MS if desired for more challenging work such as biological and/or clinical studies.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Suplementos Nutricionais/análise , Pausinystalia/química , Ioimbina/análise , Laboratórios , Espectrometria de Massas , Casca de Planta/química , Espectrofotometria Ultravioleta
14.
J Cereb Blood Flow Metab ; 35(3): 501-11, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25564241

RESUMO

We quantified the binding potentials (BPND) of [(11)C]yohimbine binding in rat brain to alpha-2 adrenoceptors to evaluate [(11)C]yohimbine as an in vivo marker of noradrenergic neurotransmission and to examine its sensitivity to the level of noradrenaline. Dual [(11)C]yohimbine dynamic positron emission tomography (PET) recordings were applied to five Sprague Dawley rats at baseline, followed by acute amphetamine administration (2 mg/kg) to induce elevation of the endogenous level of noradrenaline. The volume of distribution (VT) of [(11)C]yohimbine was obtained using Logan plot with arterial plasma input. Because alpha-2 adrenoceptors are distributed throughout the brain, the estimation of the BPND is complicated by the absence of an anatomic region of no displaceable binding. We used the Inhibition plot to acquire the reference volume, VND, from which we calculated the BPND. Acute pharmacological challenge with amphetamine induced a significant decline of [(11)C]yohimbine BPND of ~38% in all volumes of interest. The BPND was greatest in the thalamus and striatum, followed in descending order by, frontal cortex, pons, and cerebellum. The experimental data demonstrate that [(11)C]yohimbine binding is sensitive to a challenge known to increase the extracellular level of noradrenaline, which can benefit future PET investigations of pathologic conditions related to disrupted noradrenergic neurotransmission.


Assuntos
Encéfalo/diagnóstico por imagem , Pausinystalia/metabolismo , Compostos Radiofarmacêuticos/metabolismo , Animais , Radioisótopos de Carbono , Tomografia por Emissão de Pósitrons/métodos , Ratos , Ratos Sprague-Dawley , Receptores Adrenérgicos alfa 2/metabolismo
15.
J Nat Prod ; 77(11): 2504-12, 2014 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-25333996

RESUMO

Seven new indole alkaloids (1-7) comprising four vobasine, two tacaman, and one corynanthe-tryptamine bisindole alkaloid were isolated from the stem-bark extract of a Malayan Tabernaemontana. Two of the new vobasine alkaloids (1, 3), as well as 16-epivobasine (15) and 16-epivobasenal (17), showed appreciable cytotoxicity toward KB cells (IC50 ca. 5 µg/mL). The structure of the known Tabernaemontana alkaloid tronoharine (8) was revised based on newly acquired NMR data, as well as X-ray diffraction analysis.


Assuntos
Antineoplásicos Fitogênicos/isolamento & purificação , Antineoplásicos Fitogênicos/farmacologia , Alcaloides Indólicos/isolamento & purificação , Alcaloides Indólicos/farmacologia , Plantas Medicinais/química , Tabernaemontana/química , Antineoplásicos Fitogênicos/química , Cristalografia por Raios X , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Alcaloides Indólicos/química , Indóis/química , Indóis/isolamento & purificação , Indóis/farmacologia , Malásia , Conformação Molecular , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Pausinystalia , Triptaminas/química , Triptaminas/isolamento & purificação , Triptaminas/farmacologia
16.
ACS Comb Sci ; 15(7): 379-86, 2013 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-23697376

RESUMO

A strategy involving a Mannich-type multicomponent assembly process followed by a 1,3-dipolar cycloaddition has been developed for the rapid and efficient construction of parent heterocyclic scaffolds bearing indole and isoxazolidine rings. These key intermediates were then readily elaborated using well-established protocols for refunctionalization and cross-coupling to access a diverse 180-member library of novel pentacyclic and tetracyclic compounds related to the Yohimbine and Corynanthe alkaloids. Several other new multicomponent assembly processes were developed to access dihydro-ß-carboline-fused benzodiazepines, pyrimidinediones, and rutaecarpine derivatives.


Assuntos
Alcaloides/síntese química , Alcaloides Indólicos/síntese química , Ioimbina/síntese química , Alcaloides/química , Técnicas de Química Combinatória , Ciclização , Alcaloides Indólicos/química , Indóis/química , Pausinystalia , Ioimbina/química
17.
J Nat Med ; 67(1): 42-50, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22402817

RESUMO

Yohimbine is the major alkaloid found in the stem bark of yohimbe, Pausinystalia johimbe (Rubiaceae), an evergreen tree native to Africa. The objectives of the current study were to provide a detailed anatomy of yohimbe bark, as well as to determine the quantity of yohimbine in the raw yohimbe products sold online. Twelve commercial raw materials of yohimbe were analyzed by microscopic and ultra performance liquid chromatography-UV-MS methods. The study revealed that three samples were probably adulterated and four other samples contained various levels of impurities. Yohimbine was not detected in one sample, whereas its presence in other samples was found to be in the range 0.1-0.91%. The present work also provides a detailed anatomy of the stem bark of yohimbe, with light and scanning electron microscopy images, for proper identification and authentication.


Assuntos
Cromatografia Líquida/métodos , Espectrometria de Massas/métodos , Microscopia/métodos , Pausinystalia/química , Casca de Planta/química , Ioimbina/análise
18.
J Pharm Biomed Anal ; 61: 142-9, 2012 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-22221902

RESUMO

A practical ultra high-performance liquid chromatography (UHPLC) method was developed for fingerprint analysis of and determination of yohimbine in yohimbe barks and related dietary supplements. Good separation was achieved using a Waters Acquity BEH C(18) column with gradient elution using 0.1% (v/v) aqueous ammonium hydroxide and 0.1% ammonium hydroxide in methanol as the mobile phases. The study is the first reported chromatographic method that separates corynanthine from yohimbine in yohimbe bark extract. The chromatographic fingerprint analysis was applied to the analysis of 18 yohimbe commercial dietary supplement samples. Quantitation of yohimbine, the traditional method for analysis of yohimbe barks, were also performed to evaluate the results of the fingerprint analysis. Wide variability was observed in fingerprints and yohimbine content among yohimbe dietary supplement samples. For most of the dietary supplements, the yohimbine content was not consistent with the label claims.


Assuntos
Suplementos Nutricionais/análise , Espectrometria de Massas/métodos , Pausinystalia/química , Casca de Planta/química , Cromatografia Líquida de Alta Pressão/métodos , Espectrofotometria Ultravioleta/métodos
19.
Int. j. morphol ; 29(4): 1256-1262, dic. 2011. ilus
Artigo em Inglês | LILACS | ID: lil-626998

RESUMO

Testicular torsion is a disorder involving the scrotum that results in a compromise of its blood supply. The aim was to investigate the effect of Pausinystallia macroceras (PM) on testicular histology following torsion-detortion at different time intervals ranging from 1 to 4 hours 65 mature male Wister rats allotted randomly into seven groups (A to G; E& F further divided into 4-subgroups). Each group/subgroup comprised 5 rats. Testis maintained in the torted position (T) for 1, 2, 3 and 4 hours in Groups A (AT1+PM), B (BT2+PM), C (CT3+PM) and D (DT4+PM). Group E subgroups (E1+PM, E2+PM, E3+PM, E4+PM -) were sham operated, without torsion served as the sham control. Group F subgroups (F1T1, F2T2, F3T3 and F4T4) were torted as in A. All animals (except groups F & G) treated with PM extract (0.1 g/kg.b.w/day) for 56 days. Group G rats (normal control). Testes processed for histological studies. In AT1+PM showed preserved seminiferous tubules. BT2+PM, revealed varying number of necrosed and apoptotic seminiferous tubules. Group CT3+PM rats were similar to BT2+PM although with a slightly higher proportion of seminiferous tubules had undergone necrosis. In DT4+PM, sections showed few viable spermatozoa within the seminiferous tubules. When compared to the torted group F; showed extensive areas of seminiferous tubular necrosis (F3T3) as well as damage to the interstitium; while in F4T4 there were no viable testicular tissues seen. In conclusion, PM significantly prevented the cellular changes and cell death observed especially in group AT1+PM and BT2+PM.


La torsión testicular es un trastorno que involucra el escroto resultando en un compromiso del suministro sanguíneo. El objetivo fue investigar el efecto de Pausinystallia macroceras (PM) en la histología testicular tras torsión-detorsión a intervalos de tiempo diferentes que van desde 1 a 4 horas en 65 ratas macho Wistar maduras, asignando aleatoriamente en siete grupos (desde A a G, mientras que E y F se dividieron en 4 subgrupos). Cada grupo/subgrupo estuvo compuesto por 5 ratas. Los testículos se mantuvieron en posición torsionada (T) durante 1, 2, 3 y 4 horas en los grupos A (AT1 + PM), B (BT2 + PM), C (CT3 + PM) y D (DT4 + PM). El grupo E, subgrupos (E1 + PM, E2 + PM + PM E3, E4 + PM) fueron operados por modelo sham sin torsión, que sirvió de control. El grupo F, subgrupos (F1T1, F2T2, F3T3 y F4T4) fueron torsionados como en A. Todos los animales (excepto los grupos F y G) fueron tratados con extracto de AM (0,1 g/kg peso corporal/día) durante 56 días. El grupo G fueron ratas control (control normal). Los testículos fueron procesados para el estudio histológico. En AT1 + PM se observó preservación de los túbulos seminíferos. BT2 + PM, reveló un número variable de túbulos seminíferos con necrosis y apoptosis. El grupo de ratas CT3 + PM fue similar a BT2 + PM, aunque un porcentaje ligeramente superior de los túbulos seminíferos mostraron necrosis. En DT4 + PM, los cortes mostraron pocos espermatozoides viables dentro de los túbulos seminíferos. En comparación con el grupo F torsionado mostró extensas áreas de necrosis tubular (F3T3), así como daños en el intersticio; mientras que en F4T4 no hubo tejido testicular viable. En conclusión, PM previno significativamente cambios celulares y la muerte celular observada, especialmente en el grupo AT1 + PM y BT2 + PM.


Assuntos
Humanos , Masculino , Ratos , Extratos Vegetais/administração & dosagem , Pausinystalia/química , Torção do Cordão Espermático/patologia , Torção do Cordão Espermático/tratamento farmacológico , Cuidados Paliativos , Ratos Wistar , Traumatismo por Reperfusão , Fatores de Tempo , Testículo , Testículo/patologia
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