De novo in vitro shoot morphogenesis from shoot tip-induced callus cultures of Gymnema sylvestre (Retz.) R. Br. ex Sm

BACKGROUND: Gymnema sylvestre is a medicinal woody perennial vine known for its sweetening properties and antidiabetic therapeutic uses in the modern and traditional medicines. Its over-exploitation for the therapeutic uses and to meet the demand of pharmaceutical industry in raw materials supply for the production of anti-diabetic drugs has led to considerable decline in its natural population. RESULTS: An efficient system of shoot bud sprouting from nodal segment explants and indirect plant regeneration from apical meristem-induced callus cultures of G. sylvestre have been developed on Murashige and Skoog (MS) medium amended with concentrations of cytokinins. Of the three growth regulators tested, N6-benzylaminopurine (BAP) was the most efficient and 2.0 mg L-1 gave the best shoot formation efficiency. This was followed by thidiazuron (TDZ) and kinetin (Kin) but, most of the TDZ-induced micro shoots showed stunted growth. Multiple shoot formation was observed on medium amended with BAP or TDZ at higher concentrations. The produced micro shoots were rooted on half strength MS medium amended with auxins and rooted plantlets acclimatized with 87% survival of the regenerates. CONCLUSIONS: The developed regeneration system can be exploited for genetic transformation studies, particularly when aimed at producing its high yielding cell lines for the anti-diabetic phytochemicals. It also offers opportunities for exploring the expression of totipotency in the anti-diabetic perennial vine.

Effects of Ayurvedic Rasayana botanicals on CYP3A4 isoenzyme system / 中西医结合学报

<p><b>OBJECTIVE</b>Consuming botanical dietary supplements or herbal drugs along with prescription drugs may lead to potential pharmacokinetic-pharmacodynamic (PK-PD) herb-drug interactions (HDI). The present study focuses on the importance of and novel approach for assessing HDI in integrative medicine with case examples of two frequently-used Ayurvedic Rasayana botanicals.</p><p><b>METHODS</b>The aqueous extracts of Asparagus racemosus (ARE) and Gymnema sylvester (GSE) were prepared as per Ayurvedic Pharmacopoeia of India. Chemoprofiling of these extracts was done using high-performance liquid chromatography (HPLC). Additionally, ARE was characterized for the presence of shatavarins IV and I using HPLC & mass spectroscopy respectively. Effects of ARE and GSE were investigated on rat liver microsome using testosterone probe drug assay. The changes in formation of metabolite (6-β hydroxy testosterone) were monitored on incubation of testosterone alone, testosterone with ketoconazole, ARE and GSE using HPLC. Half inhibitory concentration (IC50) was used to predict plausible HDI.</p><p><b>RESULTS</b>ARE and GSE showed no inhibition with IC50 values >1 000 μg/mL while the standard inhibitor ketoconazole completely abolished CYP3A4-dependent activity at 0.531 μg/mL and IC50 was found to be 0.036 μg/mL.</p><p><b>CONCLUSION</b>ARE and GSE prepared as per Ayurvedic Pharmacopoeia of India were found to be safe for CYP3A4-mediated inhibitory HDI in rats. Our in vitro study suggests the need of further in vivo investigation for HDI in order to provide clinical relevance.</p>

Chemical constituents from the stems of Gymnema sylvestre / 中国天然药物

AIM@#To study the chemical constituents of stems of Gymnema sylvestre (Retz.) Schult.@*METHODS@#Chromatographic techniques using silica gel, C18 reversed phase silica gel, and prep-HPLC were used. The structures were elucidated on the basis of MS and spectroscopic analysis (1D and 2D NMR), as well as chemical methods.@*RESULTS@#Seven compounds were isolated and their structures were elucidated as conduritol A (1), stigmasterol (2), lupeol (3), stigmasterol-3-O-β-D-glucoside (4), the sodium salt of 22α-hydroxy-longispinogenin-3-O-β-D-glucopyranosyl-(1→3)-β-D-glu-curono-pyranosyl-28-O-α-L-rhamnopyranoside (5), oleanolic acid-3-O-β-D-glucopyranosyl-(1→6)-β-D-glucopyranoside (6), and the sodium salt of 22α-hydroxy-longispinogenin 3-O-β-D-glucuronopyranosyl-28-O-α-L-rhamnopyranoside (7). The inhibition activities of compounds 1, 5-7 on non-enzymatic glycation of protein in vitro were evaluated.@*CONCLUSION@#Compound 7 is a new triterpenoid saponin. It was shown that compounds 1, 5-7 have weak inhibition activities for non-enzymatic glycation of protein in vitro.

Toxicity of saponin isolated from Gymnema sylvestre R. Br. (Asclepiadaceae) against Culex tritaeniorhynchus Giles (Diptera: Culicidae) Japanese encephalitis vector mosquito in India / Toxicidade da saponina isolada de Gymnema sylvestre R. Br. (Asclepiadaceae) contra Culex tritaeniorhynchus Giles (Diptera: Culicidae) mosquito vetor da encefalite japonesa na Índia

To determine the larvicidal activity of various extracts of Gymnema sylvestre against the Japanese Encephalitis vector, Culex tritaeniorynchus in Tamilnadu, India. To identify the active principle present in the promising fraction obtained in Chlorofom:Methanol extract of Fraction 2. The G. sylvestre leaf extracts were tested, employing WHO procedure against fourth instar larvae of C. tritaeniorhynchus and the larval mortalities were recorded at various concentrations (6.25, 12.5, 25.0, 50 and 100 µg/mL); the 24h LC50 values of the G. Sylvestre leaf extracts were determined following Probit analysis. It was noteworthy that treatment level 100 µg/mL exhibited highest mortality rates for the three different crude extracts and was significantly different from the mean mortalities recorded for the other concentrations. The LC50 values of 34.756 µg/mL (24.475-51.41), 31.351 µg/mL (20.634-47.043) and 28.577 µg/mL (25.159-32.308) were calculated for acetone, chloroform and methanol extract with the chi-square values of 10.301, 31.351 and 4.093 respectively. The present investigation proved that G. Sylvestre could be possibly utilized as an important component in the Vector Control Program.

O presente trabalho é para identificar a atividade larvicida de vários extratos da Gymnema sylvestre contra o vetor da encefalite japonesa, Culex tritaeniorhynchus em Tamilnadu, Índia. Com este propósito o princípio ativo presente na fração mais promissora foi obtida através de um extrato clorofórmio:metanol da fração 2. Os extratos das folhas do G. sylvestre foram testados empregando o procedimento da WHO contra estágios quaternários da larva do C. tritaeniorhynchus e as mortalidades larvais foram registradas após várias concentrações (6,25, 12,5, 25,0 e 100; 34,756 µg/mL (24,475-51,41), 31,351 µg/mL (20,634-47,043) e 28,577 µg/mL (25,159-32,308) g/mL); os valores de LC50 de 24 horas dos extratos das folhas de G. sylvestre foram determinados seguindo a análise Probit. Foi notado que o nível de tratamento de 100 µg/mL exibiu a mortalidade mais alta para os três diferentes extratos crus e foi significantemente diferente das mortalidades médias registradas para as outras concentrações. Os valores de LC50 de 34,756 µg/mL (24,475-51,41), 31,351 µg/mL (20,634-47,043) e 28,577 µg/mL (25,159-32,308) foram calculados para os extratos de acetona, clorofórmio e metanol com os valores de qui-quadrado de 10,301, 31,351 e 4,093 respectivamente. A presente investigação mostra que o G. sylvestre pode ser usado como componente importante no programa de controle do vetor.

Estudos de pré-formulação de cápsulas gelatinosas duras contendo formulação de extrato de Gymnema sylvestre em pó / Preformulation studies of Gymnema sylvestre extract powder formulation for hard gelatin capsules

Gymnema sylvestre extract (GSE) is a plant product widely used as an adjuvant in the treatment of diabetes mellitus and commercially available as a powder. Owing to its low flowability, the manufacturing of hard gelatin capsules containing GSE faces specific problems. The purpose of this study was to investigate the best excipient (starch, lactose or microcrystalline cellulose) for hard gelatin capsules containing GSE. The technological properties such us bulk density (ñâ); tapped density (ñt); inter-particle porosity (Ie); Carr index (CI); Hausner ratio (HR); loss on drying (%LOD) and particle size distribution (%Pf) of the various GSE mixtures were investigated with the aim of identifying the best excipient. The need for lubricants (talc/magnesium stearate) was also assessed. GSE was characterized as a fine powder with more than 50% of its particles between 0.149mm to 0.250mm; furthermore, CI=25.6%; RH=1.3 and Ie = 25.6% and, as expected with such properties, it showed poor flowability. All the excipients investigated were able to change the technological properties of GSE and the powder mixture containing microcrystalline cellulose gave the best results.

O extrato seco de Gymnema sylvestre (EGS) é um produto fitoterápico amplamente utilizado como adjuvante no tratamento da diabetes, sendo comercializado na forma de pó. O objetivo do presente estudo foi investigar a influência da adição de adjuvantes (amido, lactose ou celulose microcristalina) à formulação para a preparação de cápsulas gelatinosas duras contendo o EGS. As propriedades tecnológicas como densidade aparente (Da), densidade aparente de compactação (Dc), porosidade interparticulas (Ie), Índice de Carr (IC), Fator de Hausner (FH), perda por dessecação (PD%) e análise do tamanho de partículas (%Pf) das diferentes misturas preparadas foram investigadas com o objetivo de escolher o melhor excipiente. A necessidade de agentes lubrificantes (talco/estearato de magnésio) também foi avaliada. O EGS foi caracterizado como um pó fino, com mais de 50% do material particulado compreendido entre 0,149-0,250mm; IC=25,6%; FH=1,3 and Ie = 25,6%, o que justifica seu fluxo pobre. Todos os excipientes testados foram capazes de modificar as propriedades tecnológicas do EGS, sendo a mistura de pós que apresentou melhores resultados aquela obtida com a adição de celulose microcristalina.

Experimental corrected study of hypoglycemic activity of conduritol A of stems of Gymnema sylvestre / 中国中药杂志

<p><b>OBJECTIVE</b>To investigates the mechanism of hypooglycemic effect of conduritol A of stems of Gymnema sylvestre.</p><p><b>METHOD</b>Fourteen days later after administration, observation is taken on the change of these mice and rats weight, the FBG, TG, CHO, SOD, MDA, INS, TNF in serum were also detected with enzymology method and Radioimmuoassay method. Take the liver to determine the disposal of glucose. Take the pancreas to do the HE and immunohistochemistrial staining, and show pancreas islet beta-cell. Calulate thymus, pancreas, splenica index.</p><p><b>RESULT</b>Compared with diabetic model mice, high and middosage of conduritol A could remarkably reduce fasted blood sugar in diabetic rats induced by alloxan (P < 0.01). Significantly increase the level of serum insulin (P < 0.05). Activity of SOD was obviously increased, and amount of MDA was obviously decreased (P < 0.05). The amount of conduritol A disposal of glucose was obviously increased (P < 0.05). Significantly increase thymus, pancreas, splencia index (P < 0.01 or 0.05); inhibited the atrophy of thymus, pancreas, splencias of the diabetic rats induced by alloxan. Compared with diabetic model group, cell structure and form of conduritol A had been some way improved. The immunohistochemistry results showed that beta-cells numbers of pancreas in each conduritol A group were more than those in the model group.</p><p><b>CONCLUSION</b>Conduritol A could have an effect on regulating the metabolism of blood lipid, free-radical scavenging, enhancing the antioxidant ability, potentiating immune function. Promoting synthesis of hepatic to decrease fasted blood suger.</p>

Investigação do potencial antidiabético e hipolipemiante de cápsulas dde folhas secas pulverizadas de Gimnema® em ratos não diabéticos ou portadores de diabetes induzido por Aloxana / Inquiry of the antidiabetic and hipolipidemic potential of dried powdered leaf capsules of Gimnema® in not diabetic or carrying rats of diabetes induced for Aloxana

Objetivo: Investigar o potencial antidiabético e hipolipemiatne de cápsulas contendo folhas secas pulverizadas de Gymnema sylvestre (GS) em ratos Wistas. Materias e Métodos: o efeito agudo da GS (doses de 30 ou 1000 mg/kg) administrada por gavagem na glicemia e lipidemia (triacilgliceróis, colesteroltotal e lipídios totais) de ratos não diabéticos foi investigado após: a) uma refeição balanceada; b) ingestão de amilose (1000 mg/kg) ou blicose (1000 mg/kg); c) a ingestão de uma solução oleosa (SO) composta de óleo de soja (12 mL/kg) + colesterol 1 por cento. Em adição, o efeito do tratamento com GS, administrada por gavagem, (30 mg/kg ao dia) durante 2 (sub-agudo) ou 4 semanas (crônico), no peso corpóreo, ingestão de alimento e de água, glicemia e lipidemia emratos não diabéticos ou portadores de diabetes induzido por aloxana foi investigado. A dose de GS utilizada na maioria dos experimentos, ou seja, 30 mg/kg em uma ou duas tomas ao dia, corresponde aproximadamente à dose diária empregada no tratamento do diabetes mellitus em humanos. Resultados: a GS, agudamente, não influenciou a elevação da glicemia promovida por uma refeição balanceada, amas impediu a elevação da glicemia induzida por administração de amilose ou glicose. A GS promoveu maior elevação da lipidemia (p<0.05) após administração de SO. Além disso, o tatamento sub-agudo ou crônico com a GS em ratos diabéticos e não diabéticos não influenciou (p>0.05): a) o peso corpóreo; b) a ingestão de alimento e água; c) a glicemia e lipidemia. Conclusão: a GS, na forma comercializada no Brasil, ou seja, folhas secas pulverizadas encapsuladas, não apresentou efeitos antidiabético ou hipolipemiante...