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1.
Biotechnol Lett ; 34(10): 1945-50, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22714271

RESUMO

Mitragynine is a pharmacologically-active terpenoid indole alkaloid found in Mitragyna speciosa leaves. Treatment with methyl jasmonate (10 µM) for 24 h and yeast extract (0.1 mg/ml) for 12 h were the optimum conditions of elicitation of mitragynine accumulation in a M. speciosa shoot culture. The former elicitor gave 0.11 mg mitragynine/g dry wt. Tryptophan decarboxylase and strictosidine synthase mRNA levels were enhanced in accordance with mitragynine accumulation.


Assuntos
Acetatos/farmacologia , Ciclopentanos/farmacologia , Mitragyna/efeitos dos fármacos , Mitragyna/metabolismo , Oxilipinas/farmacologia , Alcaloides de Triptamina e Secologanina/metabolismo , Leveduras/química , Descarboxilases de Aminoácido-L-Aromático/genética , Descarboxilases de Aminoácido-L-Aromático/metabolismo , Carbono-Nitrogênio Liases/genética , Carbono-Nitrogênio Liases/metabolismo , Meios de Cultura , Técnicas de Cultura , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Mitragyna/crescimento & desenvolvimento , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Brotos de Planta/efeitos dos fármacos , Brotos de Planta/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo
2.
J Ethnopharmacol ; 116(1): 173-8, 2008 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-18191353

RESUMO

Kratom (Mitragyna speciosa Korth.) is an indigenous plant of Thailand used traditionally in folk medicine although it is claimed to cause addiction. It is used to treat diarrhea, however, there is no scientific evidence to support the use. The aim of this study is to investigate the effect of methanolic extract of kratom leaves on the rat gastrointestinal tract. Kratom extract at 50, 100, 200 and 400 mg/kg (p.o.) caused a dose dependent protection against castor oil-induced diarrhea in rats and also inhibited intestinal transit. The antidiarrheal effect was not antagonized by naloxzone. The inhibition of intestinal transit by kratom extract was significantly different from the control when treated with a single dose for 1 day. For longer-term treatments of 15 and 30 days, kratom extract did not decrease the intestinal transit time indicating that adaptation had occurred. Kratom extract at a dose level of 200 and 400 mg/kg for 30 days and morphine at 3 mg/kg (i.p.) caused a decrease in the increment of body weight that was significantly different from the control and kratom extract at lower doses (50 and 100 mg/kg). However it had no effect on the level of plasma cholecystokinin. The results suggested that methanolic kratom extract exhibited its antidiarrheal effect on rat gastrointestinal tract. The effects may occur via pathways in addition to the action on opioid receptors. High does of kratom extract decreased the increment of body weight similar to the effect of morphine.


Assuntos
Antidiarreicos/farmacologia , Trânsito Gastrointestinal/efeitos dos fármacos , Mitragyna , Extratos Vegetais/farmacologia , Animais , Peso Corporal/efeitos dos fármacos , Colecistocinina/sangue , Medicina Tradicional do Leste Asiático , Naloxona/farmacologia , Folhas de Planta , Ratos , Ratos Wistar
3.
Z Naturforsch C J Biosci ; 63(9-10): 691-8, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-19040109

RESUMO

Hairy root cultures of Mitragyna speciosa were established by infection of Agrobacterium rhizogenes ATCC 15834 and maintained in McCown woody plant medium (WPM) supplemented with 0.5 mg/1 naphthaleneacetic acid. The hairy roots were identified for the rooting genes loci of rolA and rolB by polymerase chain reaction. For studying the secondary metabolite production, the n-hexane extract of the hairy roots was prepared and the compounds were isolated by silica gel column chromatography, affording triterpenoids (ursolic acid and oleanolic acid) and phytosterols (beta-sitosterol and stigmasterol). The shoots from the hairy root cultures were regenerated and differentiated to the plantlets. For micropropagation, shoot multiplication was successfully induced from the axillary buds of the regenerated plantlets in WPM supplemented with 0.1 mg/l thidiazuron. The mitragynine contents of 5-month-old regenerated plants and in vitro plantlets (germinated from seeds) were determined using the TLC-densitometric method. The regenerated plants contained (14.25 +/- 0.25) mg/g dry wt mitragynine, whereas the in vitro plantlets contained (4.45 +/- 0.09) mg/g dry wt.


Assuntos
Mitragyna/metabolismo , Raízes de Plantas/metabolismo , Alcaloides de Triptamina e Secologanina/metabolismo , Técnicas de Cultura de Células , Cromatografia Líquida de Alta Pressão , Primers do DNA , Hexanos , Espectroscopia de Ressonância Magnética , Mitragyna/genética , Mitragyna/fisiologia , Folhas de Planta/metabolismo , Raízes de Plantas/citologia , Raízes de Plantas/genética , Raízes de Plantas/fisiologia , Reação em Cadeia da Polimerase , Regeneração , Rhizobium/metabolismo , Alcaloides de Triptamina e Secologanina/química , Triterpenos/isolamento & purificação , Triterpenos/metabolismo , Ácido Ursólico
4.
Neurosci Lett ; 416(2): 128-32, 2007 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-17316993

RESUMO

Mitragyna speciosa (MS) has been traditionally used for medicinal purposes especially in southern Thailand. Previously, an alkaloid extract of this plant was demonstrated to mediate antinociception, partly, through the descending serotonergic system. The present study investigated the stimulatory effect of the MS extract on the dorsal raphe nucleus and its antidepressant-like activity. The MS extract containing approximately 60% mitragynine as a major indole alkaloid was used to treat the animals. The stimulatory effect of the MS extract was determined by detecting the expression of the immediate early gene, cfos, in the dorsal raphe nucleus of male Wistar rats. The immunohistochemistry was used to detect Fos protein, the protein product of cfos gene. The present data show that a significant increase in Fos expression was observed following long-term administration of the MS extract (40 mg/kg) for 60 consecutive days. In addition, the antidepressant-like activity of the MS extract was determined by using the forced swimming test (FST) in male mice. The results show that a single injection (either 60 or 90 mg/kg doses) significantly decreased immobility time in the FST. These findings indicate that the MS extract has a stimulatory effect on the dorsal raphe nucleus and an antidepressant-like activity. Stimulation of this brain area has been known to cause antinociception. These findings suggest that the MS extract might produce antinociceptive and/or antidepressive actions partly through activation of the dorsal raphe nucleus. Moreover, the dorsal raphe nucleus may be one of site of MS action in the central nervous system.


Assuntos
Alcaloides Indólicos/farmacologia , Mitragyna/química , Extratos Vegetais/farmacologia , Proteínas Proto-Oncogênicas c-fos/efeitos dos fármacos , Núcleos da Rafe/efeitos dos fármacos , Alcaloides de Triptamina e Secologanina/farmacologia , Animais , Imuno-Histoquímica , Masculino , Atividade Motora/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-fos/metabolismo , Núcleos da Rafe/metabolismo , Ratos , Ratos Wistar , Estresse Psicológico/metabolismo
5.
Fitoterapia ; 78(3): 182-5, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17335995

RESUMO

Administration of the aqueous extract of Mitragyna speciosa at a dose of 300 mg/kg significantly inhibited ethanol withdrawal-induced behaviors that included rearing, displacement and head weaving. The results also showed that at doses of 100, 300 and 500 mg/kg M. speciosa showed antidepressant activity without effect on the spontaneous motor activity.


Assuntos
Analgésicos/farmacologia , Mitragyna , Dor/prevenção & controle , Fitoterapia , Extratos Vegetais/farmacologia , Analgésicos/administração & dosagem , Analgésicos/uso terapêutico , Animais , Comportamento Animal/efeitos dos fármacos , Relação Dose-Resposta a Droga , Etanol/efeitos adversos , Masculino , Camundongos , Dor/induzido quimicamente , Medição da Dor/efeitos dos fármacos , Extratos Vegetais/administração & dosagem , Extratos Vegetais/uso terapêutico , Folhas de Planta , Síndrome de Abstinência a Substâncias/patologia
6.
Drug Test Anal ; 2017 Dec 29.
Artigo em Inglês | MEDLINE | ID: mdl-29287305

RESUMO

A lateral flow-based immunochromatographic strip was developed for the rapid detection of mitragynine (MG), a dominant alkaloid found in the leaves of kratom. Monoclonal antibody (mAb) against MG (anti-MG mAb) was conjugated to colloidal gold and used as a recognition probe. MG-ovalbumin conjugate (MG-OVA) and goat anti-mouse IgG were immobilized on the strip to produce a test zone and control zone, respectively. Based on the principle of a competitive assay, MG in a test sample competed with MG-OVA resident in the test zone to bind with colloidal gold-anti-MG mAb, resulting in an inverse relation of color intensity at the test zone and MG amount. The limit of detection (LOD) of the immunochromatographic strip is determined at 1 mg/mL of MG by visual assessment and 0.60 mg/mL by Image J analysis. The developed immunochromatographic strip can determine MG in kratom cocktails and kratom leaf samples. It could serve as a rapid and simple diagnostic kit for the detection of MG in kratom samples.

7.
J Ethnopharmacol ; 208: 129-137, 2017 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-28687506

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Mitragyna speciosa (Korth.) Havil. (M. speciosa) is among the most well-known plants used in ethnic practice of Southeast Asia. It has gained increasing attention as a plant with potential to substitute morphine in addiction treatment program. However, its action on the central nervous system is controversial. AIM OF THE STUDY: This study investigated the effects of M. speciosa alkaloid extract on naloxone-precipitated morphine withdrawal and neural signaling in the nucleus accumbens (NAc, brain reward center) of mice. MATERIALS AND METHODS: The effects of M. speciosa alkaloid extract and mitragynine, a pure major constituent, on naloxone-precipitated morphine withdrawal were examined. Male Swiss Albino (ICR) mice were rendered dependent on morphine before injection with naloxone, a nonspecific opioid antagonist, to induce morphine withdrawal symptoms. The intensity of naloxone-precipitated morphine withdrawal was assessed from jumping behavior and diarrhea induced during a period of morphine withdrawal. To test possible addictive effect of M. speciosa alkaloid extract, mice were implanted with intracranial electrode into the NAc for local field potential (LFP) recording. Following M. speciosa alkaloid extract (80mg/kg) and morphine (15mg/kg) treatment, LFP power spectra and spontaneous motor activity were analyzed in comparison to control levels. RESULTS: One-way ANOVA and multiple comparisons revealed that M. speciosa alkaloid extract (80 and 100mg/kg) significantly decreased the number of jumping behavior induced by morphine withdrawal whereas mitragynine did not. Additionally, M. speciosa alkaloid extract significantly decreased dry and wet fecal excretions induced by morphine withdrawal. LFP analysis revealed that morphine significantly decreased alpha (9.7-12Hz) and increased low gamma (30.3-44.9Hz) and high gamma (60.5-95.7Hz) powers in the NAc whereas M. speciosa alkaloid extract did not. Spontaneous motor activity was significantly increased by morphine but not M. speciosa alkaloid extract. CONCLUSIONS: Taken together, M. speciosa alkaloid extract, but not mitragynine, attenuated the severity of naloxone-precipitated morphine withdrawal symptoms. Neural signaling in the NAc and spontaneous motor activity were sensitive to morphine but not M. speciosa alkaloid extract. Therefore, treatment with the M. speciosa alkaloid extract may be useful for opiate addiction treatment program.


Assuntos
Alcaloides/uso terapêutico , Analgésicos Opioides , Mitragyna , Morfina , Extratos Vegetais/uso terapêutico , Síndrome de Abstinência a Substâncias/tratamento farmacológico , Animais , Comportamento Animal/efeitos dos fármacos , Diarreia/tratamento farmacológico , Masculino , Camundongos Endogâmicos ICR , Naloxona , Antagonistas de Entorpecentes , Núcleo Accumbens/efeitos dos fármacos , Núcleo Accumbens/fisiologia , Folhas de Planta , Alcaloides de Triptamina e Secologanina/uso terapêutico , Síndrome de Abstinência a Substâncias/etiologia
8.
Fitoterapia ; 77(5): 339-45, 2006 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16781828

RESUMO

Acute administration of Mitragyna speciosa (MS) extract (45 and 50 mg/kg) significantly resulted in dose-dependent decreases in food and water intakes (P<0.05) in rats. Prolonged suppressing effects were observed following administration of the MS extract (40 mg/kg) for 60 consecutive days. Moreover, the long-term administration also significantly suppressed weight gaining.


Assuntos
Alcaloides/farmacologia , Peso Corporal/efeitos dos fármacos , Ingestão de Líquidos/efeitos dos fármacos , Ingestão de Alimentos/efeitos dos fármacos , Mitragyna , Animais , Depressores do Apetite/farmacologia , Masculino , Extratos Vegetais/farmacologia , Ratos , Ratos Wistar
9.
Fitoterapia ; 76(6): 534-9, 2005 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-15993008

RESUMO

In the present study, we investigated the effect of the dichloromethane fraction from Areca catechu nut on the severity of naloxone-precipitated morphine withdrawal in morphine-dependent mice. A single intraperitoneal injection of dichloromethane fraction at dose of 125 and 175 mg/kg significantly delayed the onset of withdrawal jumping behavior in a concentration-dependent manner compared to that of saline controls. The dichloromethane fractions also significantly decreased jumping numbers and faecal and urinary excretions during the withdrawal period.


Assuntos
Analgésicos Opioides/efeitos adversos , Areca , Morfina/efeitos adversos , Fitoterapia , Extratos Vegetais/farmacologia , Síndrome de Abstinência a Substâncias/prevenção & controle , Animais , Comportamento Animal/efeitos dos fármacos , Relação Dose-Resposta a Droga , Masculino , Camundongos , Naloxona , Antagonistas de Entorpecentes , Nozes , Extratos Vegetais/administração & dosagem , Extratos Vegetais/uso terapêutico , Síndrome de Abstinência a Substâncias/etiologia
10.
Phytomedicine ; 22(11): 1000-8, 2015 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-26407942

RESUMO

BACKGROUND: Many antidepressants are effective in alleviating ethanol withdrawal symptoms. However, most of them suppress rapid eye movement (REM) sleep. Thus, development of antidepressants without undesirable side effects would be preferable. Previously, crude alkaloid extract from Mitragyna speciosa (MS) Korth was found to produce antidepressant activities. It was hypothesized that the alkaloid extract from MS may attenuate ethanol withdrawal without REM sleep disturbance. METHODS: Adult male Wistar rats implanted with electrodes over the frontal and parietal cortices were used for two separated studies. For an acute study, 10 mg/kg fluoxetine or 60 mg/kg alkaloid extract from MS were administered intragastrically. Electroencephalographic (EEG) signals were recorded for 3 h to examine sleep profiles and EEG fingerprints. Another set of animal was used for an ethanol withdrawal study. They were rendered dependent on ethanol via a modified liquid diet (MLD) containing ethanol ad libitum for 28 days. On day 29, fluoxetine (10 mg/kg) or alkaloid extract from MS (60 mg/kg) were administered 15 min before the ethanol-containing MLD was replaced with an isocaloric ethanol-free MLD to induced ethanol withdrawal symptoms. RESULTS: The sleep analysis revealed that alkaloid extract from MS did not change any REM parameters which included average duration of each REM episode, total REM time, number of REM episode and REM latency whereas fluoxetine significantly suppressed all REM parameters and delayed REM latency. However, power spectral analysis revealed similar fingerprints for fluoxetine and alkaloid extract from MS characterized by decreasing powers in the slow frequency range in frontal and parietal cortical EEG. Neither treatment affected spontaneous motor activity. Finally, both alkaloid extract from MS and fluoxetine were found to significantly attenuate ethanol withdrawal-induced hyperexcitability (increases gamma activity) in both cortices and to reduce locomotor activity. CONCLUSION: The present study demonstrated that the alkaloid extract from MS alleviates ethanol withdrawal severity with no side effect on REM sleep. In addition, these data suggest that suppressive effects on slow frequency powers but not REM sleep may be hallmarks of effective antidepressants for ethanol withdrawal treatment.


Assuntos
Alcaloides/farmacologia , Fluoxetina/farmacologia , Mitragyna/química , Extratos Vegetais/farmacologia , Sono REM/efeitos dos fármacos , Síndrome de Abstinência a Substâncias/tratamento farmacológico , Animais , Eletrodos , Eletroencefalografia , Etanol/efeitos adversos , Masculino , Folhas de Planta/química , Ratos , Ratos Wistar
11.
Pharmaceutics ; 7(2): 10-26, 2015 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-25825913

RESUMO

Detoxification and elimination of permethrin (PM) are mediated by hydrolysis via carboxylesterase (CES). Mitragyna speciosa (kratom) contains mitragynine (MG) and other bioactive alkaloids. Since PM and MG have the same catalytic site and M. speciosa is usually abused by adding other ingredients such as pyrethroid insecticides, the effects of MG and an alkaloid extract (AE) on the elimination of PM were investigated in rats. Rats were subjected to single and multiple pretreatment with MG and AE prior to receiving a single oral dose (460 mg/kg) of PM. Plasma concentrations of trans-PM and its metabolite phenoxybenzylalcohol (PBAlc) were measured. The elimination rate constant (kel) and the elimination half-life (t1/2 el) of PM were determined, as well as the metabolic ratio (PMR). A single and multiple oral pretreatment with MG and AE altered the plasma concentration-time courses of both trans-PM and PBAlc during 8-22 h, decreased the PMRs, delayed elimination of PM, but enhanced elimination of PBAlc. Results indicated that PM-MG or AE toxicokinetic interactions might have resulted from the MG and AE interfering with PM hydrolysis. The results obtained in rats suggest that in humans using kratom cocktails containing PM, there might be an increased risk of PM toxicity due to inhibition of PM metabolism and elimination.

12.
Org Lett ; 5(16): 2879-82, 2003 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-12889898

RESUMO

[structure: see text] Commonly used among ingredients in Thai traditional anticancer preparations, the rhizome of Dioscorea membranacea Pierre was found potently cytotoxic and possibly contributed to such a therapeutic effect. Bioassay-guided isolation resulted in two novel cytotoxic naphthofuranoxepins, dioscorealides A (1) and B (2), and a new 1,4-phenanthraquinone, dioscoreanone (3). The structure determination, achieved mainly by means of NMR and CD spectral and X-ray crystallographic analyses, and cytotoxicity are discussed here.

13.
Forensic Sci Int ; 244: 70-7, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25216455

RESUMO

Monoclonal antibody (MAb) against mitragynine (MG), an analgesic alkaloid from Kratom leaves (Mitragyna speciosa), was produced. MG was coupled to carrier proteins employing either 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide/N-hydroxysuccinimide (EDC/NHS), a zero-length cross linker or a 5-carbon length glutaraldehyde cross linker. To confirm the immunogenicity, the hapten numbers were determined using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS). Preparation of the MAb was accomplished by the electrofusion method. Hybridoma 1A6 that was constructed from the fusion between splenocytes of EDC/NHS conjugate immunized mice and SP2/0-Ag14 myeloma cells was selected, cloned twice and expanded. The cross-reactivities (CRs) of this MAb 1A6 with a series of indole alkaloids were 30.54%, 24.83% and 8.63% for speciogynine, paynantheine and mitraciliatine, respectively. Using this MAb, an indirect competitive enzyme-linked immunosorbent assay (icELISA) was developed with a measurement range of 32.92-250 µg/mL. Quantitative analysis of the MG contents in plant samples by icELISA correlated well with the standard high performance liquid chromatography method (R(2)=0.994). The MAb against mitragynine provided a tool for detection of MG in Kratom preparations.


Assuntos
Anticorpos Monoclonais/imunologia , Mitragyna/química , Folhas de Planta/química , Alcaloides de Triptamina e Secologanina/análise , Animais , Ensaio de Imunoadsorção Enzimática/métodos , Camundongos Endogâmicos BALB C
14.
Forensic Sci Int ; 217(1-3): 81-6, 2012 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-22018854

RESUMO

A simple HPLC technique for determining mitragynine, codeine, caffeine, chlorpheniramine and phenylephrine in 'kratom cocktail' was developed. The analytical method for mitragynine, codeine and caffeine used an Eclipse XDB-C8 column. A Lichrospher CN column was using for analysing chlorpheniramine and phenylephrine. The correlation coefficient of each standard was between 0.9957 and 0.9993. The precision of the methods were between 0.700 and 7.108% RSD. The concentration of mitragynine, codeine, caffeine, chlorpheniramine and phenylephrine in 'kratom cocktail' was 90.021, 234.174, 73.986, 7.053 and 1.486 mg/L, respectively.

15.
J Ethnobiol Ethnomed ; 8: 34, 2012 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-22931752

RESUMO

BACKGROUND: Traditional Dai Medicine (TDM) is one of the four major ethnomedicine of China. In 2007 a group of experts produced a set of seven Dai medical textbooks on this subject. The first two were selected as the main data source to analyse well recognized prescriptions. OBJECTIVE: To quantify patterns of prescriptions, common ingredients, indications and usages of TDM. METHODS: A relational database linking the prescriptions, ingredients, herb names, indications, and usages was set up. Frequency of pattern of combination and common ingredients were tabulated. RESULTS: A total of 200 prescriptions and 402 herbs were compiled. Prescriptions based on "wind" disorders, a detoxification theory that most commonly deals with symptoms of digestive system diseases, accounted for over one third of all prescriptions. The major methods of preparations mostly used roots and whole herbs. CONCLUSION: The information extracted from the relational database may be useful for understanding symptomatic treatments. Antidote and detoxification theory deserves further research.


Assuntos
Bases de Dados Factuais , Medicamentos de Ervas Chinesas/uso terapêutico , Gastroenteropatias/tratamento farmacológico , Medicina Tradicional Chinesa , Livros de Texto como Assunto , China , Gastroenteropatias/diagnóstico , Humanos , Raízes de Plantas , Prescrições
16.
Nat Prod Res ; 25(15): 1379-87, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18846471

RESUMO

The leaves of Mitragyna speciosa Korth (Rubiaceae) have been used in folk medicine for its unique medicinal properties. This study examined the water, methanolic and crude alkaloidal extracts from M. speciosa leaves and its major constituent mitragynine for the enhancement of glucose transport. Cellular uptake of radioactive 2-deoxyglucose was determined in rat L8 myotubes. Involving signalling pathway was determined with the specific inhibitors. Cell cytotoxicity was monitored by lactate dehydrogenase assay. Protein levels of glucose transporters (GLUTs) were measured by Western blotting. The results show that test samples significantly increased the rate of glucose uptake. The uptake was associated with increase in GLUT1 protein content. Co-incubation with insulin had no additional effect, but the cellular uptake was decreased by wortmannin and SB 203580, specific inhibitors of phosphatidylinositol 3-kinase (PI3K) and p38 mitogen-activated protein kinase (p38 MAPK), respectively. It is concluded that the increased glucose transport activity of M. speciosa is associated with increases in activities of the key enzymes dependent to the insulin-stimulated glucose transport for its acute action, and increases in the GLUT1 content for its long-term effect. This study demonstrated the effect of M. speciosa in stimulating glucose transport in muscle cells, implicating the folkloric use of M. speciosa leaves for treating diabetes.


Assuntos
Glucose/metabolismo , Mitragyna/química , Músculos/efeitos dos fármacos , Extratos Vegetais/farmacologia , Alcaloides de Triptamina e Secologanina/farmacologia , Androstadienos/farmacologia , Animais , Western Blotting , Linhagem Celular , Inibidores Enzimáticos/farmacologia , Imidazóis/farmacologia , Insulina/metabolismo , Músculos/citologia , Músculos/metabolismo , Piridinas/farmacologia , Ratos , Transdução de Sinais , Wortmanina
17.
J Ethnopharmacol ; 129(3): 344-9, 2010 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-20371282

RESUMO

AIM OF THE STUDY: The effects of pure alkaloid, mitragynine and a methanolic extract of kratom leaves were investigated on neuromuscular junction and compound nerve action potential. MATERIALS AND METHODS: Wistar rats were killed by cervical dislocation and decapitated. The phrenic nerve-hemidiaphragms, hemidiaphragms and sciatic nerve were isolated. RESULTS: Kratom methanolic extract present at 0.1-1 mg/mL and mitragynine (0.0156 mg/mL) decreased the muscle twitch on the isolated phrenic nerve-hemidiaphragm and hemidiaphragm preparation. Muscle relaxation caused by kratom extract (1 mg/mL) was greater than the effect of mitragynine. Pancuronium and succinylcholine potentiated the effect of kratom extract. It also had a direct relaxation effect on the hemidiaphragm muscle. The muscle relaxation caused by kratom extract was not antagonized by neostigmine, tetraethylammonium and calcium chloride. High concentrations of kratom extract (10-40 mg/mL) and mitragynine (2 mg/mL) blocked the nerve conduction, amplitude and duration of compound nerve action potential. CONCLUSIONS: The mechanism of action of kratom extract might not act as a competitive antagonist of acetylcholine yet its dominant effect was at the neuromuscular junction and not at the skeletal muscle or somatic nerve.


Assuntos
Mitragyna/química , Relaxamento Muscular/efeitos dos fármacos , Bloqueio Neuromuscular/métodos , Junção Neuromuscular/efeitos dos fármacos , Extratos Vegetais/farmacologia , Alcaloides de Triptamina e Secologanina/farmacologia , Animais , Diafragma/efeitos dos fármacos , Feminino , Técnicas In Vitro , Masculino , Músculo Esquelético/efeitos dos fármacos , Músculo Esquelético/inervação , Nervo Frênico/efeitos dos fármacos , Extratos Vegetais/isolamento & purificação , Folhas de Planta/química , Ratos , Ratos Wistar , Nervo Isquiático/efeitos dos fármacos , Alcaloides de Triptamina e Secologanina/isolamento & purificação
18.
Biomed Chromatogr ; 21(2): 176-83, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17221920

RESUMO

A simple HPLC technique for determining mitragynine levels in serum was developed. The separation system consisted of a C18 column heated to 35 degrees C, a methanol-water (80:20, v/v) mobile phase, a flow rate of 0.8 mL/min and detection in the ultraviolet at 225 nm. Mitragynine, with a retention time of 10.09 min, was well resolved from any interferences in human serum and the internal standard peak. The calibration curve was linear from 0.1 to 10 microg/mL (r = 0.9995). Extraction of mitragy-nine from alkalinized serum using diethyl ether gave a high recovery (>or=85%). The intra- and inter-day precisions of the method were 4.29-5.88%RSD and 7.06-8.45%RSD, respectively. The accuracy ranged from -9.54 to +0.67%DEV. The limit of detection was 0.03 microg/mL and the lower limit of quantification was 0.1 microg/mL. Mitragynine in the stock solution was stable during 30 days of storage at 4 degrees C. This method was successfully applied to determine the pharmacokinetic characteristics of mitragynine levels in the serum of rats after it was administered orally.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Alcaloides de Triptamina e Secologanina/sangue , Alcaloides de Triptamina e Secologanina/farmacocinética , Animais , Masculino , Espectrometria de Massas/métodos , Ratos , Ratos Wistar
19.
J Nat Prod ; 67(10): 1767-70, 2004 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-15497961

RESUMO

A new scalarane-type sesterterpene, 12-deacetoxyscalarin 19-acetate (2), and two naturally new derivatives of manoalide-type sesterterpenes, (E)- and (Z)-neomanoalide 24,25-diacetates (3 and 4), were isolated from the Thai sponge Brachiaster sp., along with five other known sesterterpenes: heteronemin (1), heteronemin acetate (5), 12-epi-19-deoxyscalarin (6), 12-deacetyl-12-epi-19-deoxyscalarin (7), and manoalide 25-acetate (8). The antitubercular and cytotoxic activities of all eight compounds were evaluated to reveal the potent activity of compounds 1, 2, 5, and 8. Among these, compound 2 showed an interesting bioactivity profile, in possessing potent antitubercular activity and being practically inactive in the cytotoxicity bioassay.


Assuntos
Antineoplásicos/isolamento & purificação , Antituberculosos/isolamento & purificação , Poríferos/química , Terpenos/isolamento & purificação , Animais , Antineoplásicos/química , Antineoplásicos/farmacologia , Antituberculosos/química , Antituberculosos/farmacologia , Ensaios de Seleção de Medicamentos Antitumorais , Estrutura Molecular , Sesterterpenos , Terpenos/química , Terpenos/farmacologia , Tailândia , Células Tumorais Cultivadas
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