RESUMO
A novel bioactive flavan glycoside was isolated by solvent extraction method with the help of Soxhlet apparatus from the methanolic extract of Tradescantia spathacea Sw. Flavan glycoside having molecular formula C20H22O10, melting point 175-1780C, molecular weight by ESI-MS m/z (M + H]+ 423, optical rotation was[α]21D-45.1(c 0.20 methanol). Its structure was determined (-)-epicatechin 7-O-alpha-L-arabinopyranoside. Various color reactions, chemical degradation (like acid hydrolysis, permethylation, and enzymatic hydrolysis), UV-Visible spectrophotometry, Fourier transforms infrared spectroscopy, electrospray ionization mass spectrometry, and nuclear magnetic resonance spectroscopy were used to establish the structure of compound (-)-(-)-epicatechin 7-O-alpha-L-arabinopyranoside.. A flavan glycoside was also tested with a DPPH assay method for antioxidant activity by using Ascorbic acid as standard. DPPH radical scavenging test data demonstrate that a flavan glycoside possesses potent antioxidant activity so this flavan glycoside can be utilized as a potent antioxidant agent.
Assuntos
Glicosídeos Cardíacos , Catequina , Commelinaceae , Tradescantia , Antioxidantes/farmacologia , Glicosídeos/química , Extratos Vegetais/química , Espectrometria de Massas por Ionização por ElectrosprayRESUMO
Cyanotis arachnoidea C. B. Clarke is a traditional Chinese medicinal herb that has a limited clinical use in the treatment of diabetes mellitus (DM) in minority areas of Guizhou in China. However, few prior reports are available on the quality control of Cyanotis arachnoidea, and its quality markers and hypoglycemic mechanism are still unclear. The purpose of this study is to explore the quality markers (Q-markers) of Cyanotis arachnoidea and predict its hypoglycemic mechanism. In this study, ultra-high-performance liquid chromatography (UHPLC) fingerprint combined with chemical pattern recognition were performed, and four differential components were screened out as quality markers, including 20-Hydroxyecdysone, 3-O-acetyl-20-hydroxyecdysone, Ajugasterone C, and 2-O-acetyl-20-hydroxyecdysone. Network pharmacology analysis revealed 107 therapeutic target genes of Cyanotis arachnoidea in DM treatment, and the key targets were Akt1, TNF, IL-6, MAPK3, and JUN. The hypoglycemic mode of action of Cyanotis arachnoidea may be mediated by tumor necrosis factor (TNF) signaling, cancer, insulin resistance, and JAK-STAT pathways. Molecular docking analysis disclosed that the foregoing quality markers effectively bound their key target genes. An in vitro experiment conducted on pancreatic islet ß-cells indicated that the forenamed active components of Cyanotis arachnoidea had hypoglycemic efficacy by promoting PI3K/Akt and inhibiting MAPK signaling. UHPLC also accurately quantified the quality markers. The identification and analysis of quality markers for Cyanotis arachnoidea is expected to provide references for the establishment of a quality control evaluation system and clarify the material basis and hypoglycemic mechanisms of this traditional Chinese medicine (TCM).
Assuntos
Commelinaceae , Ecdisterona , Ecdisterona/farmacologia , Simulação de Acoplamento Molecular , Farmacologia em Rede , Fosfatidilinositol 3-Quinases , Hipoglicemiantes/farmacologiaRESUMO
Ecdysteroid-containing herbal extracts, commonly prepared from the roots of Cyanotis arachnoidea, are marketed worldwide as a "green" anabolic food supplement. Herein are reported the isolation and complete 1H and 13C NMR signal assignments of three new minor ecdysteroids (compounds 2-4) from this extract. Compound 4 was identified as a possible artifact that gradually forms through the autoxidation of calonysterone. The compounds tested demonstrated a significant protective effect on the blood-brain barrier endothelial cells against oxidative stress or inflammation at a concentration of 1 µM. Based on these results, minor ecdysteroids present in food supplements may offer health benefits in various neurodegenerative disease states.
Assuntos
Commelinaceae , Doenças Neurodegenerativas , Humanos , Ecdisteroides/farmacologia , Ecdisteroides/química , Barreira Hematoencefálica , Células Endoteliais , Commelinaceae/química , Extratos Vegetais/farmacologia , Extratos Vegetais/químicaRESUMO
ETHNOPHARMACOLOGICAL RELEVANCE: Cyanotis tuberosa (Roxb.) Schult. &Schult.f. is traditionally used as ethnomedicine for curing several ailments like diabetes, liver problems, ulcers, etc. OBJECTIVE: The present study was designed to evaluate the anti-diabetic potential of Cyanotis tuberosa root tubers (CTRT)in Streptozotocin (STZ) induced diabetic rats. MATERIALS AND METHODS: Anti-hyperglycemic activity of hexane extract of CTRT was investigated in diabetic rats. Silica gel chromatography was used to fractionate the hexane extract and the fraction's antihyperglycemic activity was checked in diabetic rats. Effects of long-term (30 days) treatment with an active fraction (CTAF) were evaluated in diabetic rats for 30 days by measurement of body weights, glycemic control, insulin levels, HbA1c, and serum and tissue lipid profiles. Lipid peroxide levels and antioxidant status were measured in the liver and kidney. Hepatic and Renal functional markers were also measured. Phytochemical characterization of CTAF was carried out by LC-ESI-MS/MS analysis. RESULTS: Hexane extract of CTRT at a dose of 750 mg/kg b.w produced significant antihyperglycemic activity in diabetic rats whereas CTAF has produced maximum antihyperglycemic activity at the dose of 75 mg/kg b.w. Following long-term treatment with CTAF in diabetic rats, significant improvement in glycemic control, (HbA1c) along with decreased insulin resistance (HOMA-IR), increase in body weights, and plasma insulin were observed. Also, CTAF ameliorated the serum and tissue lipid profiles. In addition, CTAF suppressed lipid peroxidation and restored the activities of antioxidant enzymes in the liver and kidney to normal levels. Further, CTAF reversed the liver and kidney functional markers to normalcy. LC-ESI-MS/MS analysis revealed the presence of 7 different phytoconstituents. CONCLUSION: This study confirmed that CTAF exerts antidiabetic effects in diabetic rats by improving insulin secretion, glycemic control, and restoring functional activities of the liver and kidney. Our results suggest that root tubers of Cyanotis tuberosa can be used as a complementary or alternative agent for the treatment of diabetes mellitus.
Assuntos
Antioxidantes/farmacologia , Commelinaceae/química , Hipoglicemiantes/uso terapêutico , Hipolipemiantes/uso terapêutico , Extratos Vegetais/uso terapêutico , Raízes de Plantas/química , Animais , Antioxidantes/química , Biomarcadores/sangue , Glicemia/efeitos dos fármacos , Diabetes Mellitus Experimental , Teste de Tolerância a Glucose , Hipoglicemiantes/administração & dosagem , Hipolipemiantes/química , Rim/efeitos dos fármacos , Rim/metabolismo , Metabolismo dos Lipídeos/efeitos dos fármacos , Fígado/efeitos dos fármacos , Fígado/metabolismo , Masculino , Fitoterapia , Extratos Vegetais/química , Ratos , Ratos Wistar , Testes de ToxicidadeRESUMO
Ecdysteroids act as molting hormones in insects and as nonhormonal anabolic agents and adaptogens in mammals. A wide range of ecdysteroid-containing herbal extracts are available worldwide as food supplements. The aim of this work was to study such an extract as a possible industrial source of new bioactive ecdysteroids. A large-scale chromatographic isolation was performed from an extract of Cyanotis arachnoidea roots. Ten ecdysteroids (1-10) including eight new compounds were isolated and characterized by extensive nuclear magnetic resonance studies. Highly unusual structures were identified, including a H-14ß (1, 2, 4, and 10) moiety, among which a 14ß(H)17ß(H) phytosteroid (1) is reported for the first time. Compounds with an intact side chain (4-10) and 11 other natural or semisynthetic ecdysteroids (11-21) were tested for insect ecdysteroid receptor (EcR) binding activity. Two new compounds, i.e., 14-deoxydacryhainansterone (5) and 22-oxodacryhainansterone (6), showed strong EcR binding activity (IC50 = 41.7 and 380 nM, respectively). Six compounds were identified as EcR agonists and another two as antagonists using a transgenic ecdysteroid reporter gene assay. The present results demonstrate that commercial C. arachnoidea extracts are rich in new, unusual bioactive ecdysteroids. Because of the lack of an authentic plant material, the truly biosynthetic or artifactual nature of these compounds cannot be confirmed.
Assuntos
Commelinaceae/química , Ecdisteroides/química , Fitosteróis/química , Extratos Vegetais/química , Receptores de Esteroides/metabolismo , Animais , Estrutura Molecular , Raízes de Plantas/química , Células Sf9RESUMO
COVID-19, caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has reached pandemic proportions with negative impacts on global health, the world economy and human society. The clinical picture of COVID-19, and the fact that Angiotensin converting enzyme 2 (ACE2) is a receptor of SARS-CoV-2, suggests that SARS-CoV-2 infection induces an imbalance in the renin-angiotensin system (RAS). We review clinical strategies that are attempting to rebalance the RAS in COVID-19 patients by using ACE inhibitors, angiotensin receptor blockers, or agonists of angiotensin-II receptor type 2 or Mas receptor (MasR). We also propose that the new MasR activator BIO101, a pharmaceutical grade formulation of 20-hydroxyecdysone that has anti-inflammatory, anti-fibrotic and cardioprotective properties, could restore RAS balance and improve the health of COVID-19 patients who have severe pneumonia.
Assuntos
Tratamento Farmacológico da COVID-19 , Sistema Renina-Angiotensina/efeitos dos fármacos , SARS-CoV-2/patogenicidade , Antagonistas de Receptores de Angiotensina/uso terapêutico , Inibidores da Enzima Conversora de Angiotensina/uso terapêutico , Animais , COVID-19/metabolismo , COVID-19/virologia , Commelinaceae , Desenvolvimento de Medicamentos , Ecdisona/análogos & derivados , Ecdisona/uso terapêutico , Interações Hospedeiro-Patógeno , Humanos , Extratos Vegetais/uso terapêutico , Proto-Oncogene Mas , Proteínas Proto-Oncogênicas/agonistas , Proteínas Proto-Oncogênicas/metabolismo , Receptores Acoplados a Proteínas G/agonistas , Receptores Acoplados a Proteínas G/metabolismo , SARS-CoV-2/metabolismoRESUMO
The ethanolic extract of Callisia fragrans aerial parts showed a significant strong in vivo anti-inflammatory and in vitro antioxidant activities with a high in vivo gastrointestinal safety profile and a very low in vitro cytotoxicity on peripheral blood mononuclear cells (PBMCs) with an IC50 > 1000 µg/ml. The alcoholic extract of C. fragrans has been analysed by HPLC coupled to multiple-stage Linear Ion-Trap and Orbitrap High-Resolution mass spectrometry in negative electrospray ionisation mode (LC-ESI/LTQOrbitrap/MS/MSn). By this approach, it was possible to putatively identify 13 compounds, mainly organic acids, flavonoids, one steroid and one hydroxy-coumarin. Luteolin 6-C-glucopyranosyl-7-O-glucopyranoside, luteolin-8-C-glucopyranosyl-7-O-rhamnopyranoside, luteolin-6-C-glucoside and isoorientin 7-O-[6''-feruloyl]-glucoside were detected for the first time in C. fragrans and family Commelinaceae.[Figure: see text].
Assuntos
Commelinaceae , Leucócitos Mononucleares , Anti-Inflamatórios/farmacologia , Cromatografia Líquida de Alta Pressão , Egito , Flavonoides/análise , Extratos Vegetais/farmacologia , Espectrometria de Massas por Ionização por ElectrosprayRESUMO
This research aims to isolate and identify Zn- and Cd-tolerant endophytic bacteria from Murdannia spectabilis, identify their properties with and without Zn and Cd stress, and to investigate the effect of bacterial inoculation in an in vitro system. Twenty-four isolates could survive on trypticase soya agar (TSA) supplemented with Zn (250-500 mg L-1) and/or Cd (20-50 mg L-1) that belonged to the genera Bacillus, Pantoea, Microbacterium, Curtobacterium, Chryseobacterium, Cupriavidus, Siphonobacter, and Pseudomonas. Each strain had different indole-3-acetic acid (IAA), 1-aminocyclopropane-1-carboxylate (ACC) deaminase and siderophore production, nitrogen fixation, phosphate solubilization, and lignocellulosic enzyme characteristics. Cupriavidus plantarum MDR5 and Chryseobacterium sp. MDR7 were selected for inoculation into plantlets that were already occupied by Curtobacterium sp. TMIL due to them have a high tolerance for Zn and Cd while showing no pathogenicity. As determined via an in vitro system, Cupriavidus plantarum MDR5 remained in the plants to a greater extent than Chryseobacterium sp. MDR7, while Curtobacterium sp. TMIL was the dominant species. The Zn plus Cd treatment supported the persistence of Cupriavidus plantarum MDR5. Dual and mixed cultivation showed no antagonistic effects between the endophytes. Although the plant growth and Zn/Cd accumulation were not significantly affected by the Zn-/Cd-tolerant endophytes, the inoculation did not weaken the plants. Therefore, Cupriavidus plantarum MDR5 could be applied in a bioaugmentation process.
Assuntos
Actinomycetales/efeitos dos fármacos , Actinomycetales/fisiologia , Cádmio/farmacologia , Commelinaceae/microbiologia , Cupriavidus/efeitos dos fármacos , Cupriavidus/fisiologia , Zinco/farmacologia , Antibiose , Biodegradação Ambiental , Carbono-Carbono Liases/metabolismo , Endófitos/classificação , Endófitos/isolamento & purificação , Ácidos Indolacéticos/metabolismo , Raízes de Plantas/microbiologia , Sideróforos/metabolismo , Poluentes do Solo/farmacologiaRESUMO
OBJECTIVE: To explore the total phenolic and flavonoid content, enzymatic, non-enzymatic antioxidant properties, anti-inflammation and anticancer activities of hexane, ethyl acetate and methanol extracts of Floscopa scandens (F. scandens). METHODS: Non-enzymatic antioxidant activity was examined by 2, 2-diphenyl-1-picrylhydrazyl assay, nitric oxide scavenging assay, hydroxyl radical scavenging assay, reducing power assay, hydrogen peroxide scavenging assay, superoxide scavenging assay and metal chelating assay. Enzymatic antioxidant ability was screened for the antioxidant enzymes such as ascorbate oxidase, peroxidase, catalase and polyphenol oxidase. The anti-inflammatory property was proved with the inhibition of protein denaturation and protease inhibitory assays. In vitro anticancer activity was assessed by cell viability assay. RESULTS: Methanol extract contained high amount of phenols (198.41 mg catechol equivalent/gram extract) and flavonoids (101.70 mg quercetin equivalent/gram extract) showed higher activity than hexane and ethyl acetate extracts in all experiments. Fresh plant showed considerable enzymatic antioxidant activity. CONCLUSION: The results revealed that the methanol extracts of F. scandens could be used as a potential source of antioxidant, anti-inflammatory and anticancer bioactive compounds.
Assuntos
Anti-Inflamatórios/química , Antineoplásicos/química , Antioxidantes/química , Commelinaceae/química , Inibidores Enzimáticos/química , Extratos Vegetais/química , Anti-Inflamatórios/farmacologia , Antineoplásicos/farmacologia , Antioxidantes/farmacologia , Ascorbato Oxidase/antagonistas & inibidores , Ascorbato Oxidase/química , Catalase/antagonistas & inibidores , Catalase/química , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Flavonoides/química , Flavonoides/farmacologia , Humanos , Peroxidase/antagonistas & inibidores , Peroxidase/química , Fenóis/química , Fenóis/farmacologia , Extratos Vegetais/farmacologia , Folhas de Planta/química , Quercetina/química , Quercetina/farmacologiaRESUMO
During meiosis in microsporogenesis, autonomous cellular organelles, i.e., plastids and mitochondria, move and separate into daughter cells according to a specific pattern. This process called chondriokinesis is characteristic for a given plant species. The key criterion for classification of the chondriokinesis types was the arrangement of cell organelles during two meiosis phases: metaphase I and telophase I. The autonomous organelles participate in cytoplasmic inheritance; therefore, their precise distribution to daughter cells determines formation of identical viable microspores. In this study, the course of chondriokinesis during the development of the male gametophyte in Tinantia erecta was analyzed. The study was conducted using optical and transmission electron microscopes. During microsporogenesis in T. erecta, autonomous cell organelles moved in a manner defined as a neutral-equatorial type of chondriokinesis. Therefore, metaphase I plastids and mitochondria were evenly dispersed around the metaphase plate and formed an equatorial plate between the daughter nuclei in early telophase I. Changes in the ultrastructure of plastids and mitochondria during pollen microsporogenesis were also observed.
Assuntos
Commelinaceae/citologia , Gametogênese Vegetal , Mitocôndrias/ultraestrutura , Plastídeos/ultraestrutura , Pólen/citologia , Commelinaceae/fisiologia , Commelinaceae/ultraestrutura , Meiose , Microscopia Eletrônica de Transmissão , Mitocôndrias/metabolismo , Plastídeos/metabolismo , Pólen/fisiologia , Pólen/ultraestruturaRESUMO
Phytoecdysteroids are known for their various beneficial bioactivities in mammals including a non-hormonal anabolic and adaptogenic effect. Cyanotis arachnoidea extracts are extensively utilized worldwide as ecdysteroid-rich materials for various purposes, e.g. food supplementation, use in agriculture and aquaculture, etc. Preparative chromatography of ecdysteroids requires extensive use of methods of different selectivity, and only a very limited number of papers are available on related application of modern liquid-liquid chromatographic techniques. In this work, a centrifugal partition chromatography (CPC) method was developed for the isolation of two minor ecdysteroids, dacryhainansterone and calonysterone, from a pre-purified commercial extract of Cyanotis arachnoidea. The biphasic solvent system was optimized by HPLC, and was composed of n-hexane - ethyl acetate - methanol - water (1:5:1:5, v/v/v/v). The isolated dacryhainansterone and calonysterone represented 99.1% and 99.7% purity, respectively. Calonysterone exerts a stronger effect on the protein kinase B (Akt) phosphorylation in mammalian skeletal muscle cells than the abundant 20-hydroxyecdysone, while no related data are available on dacryhainansterone. Despite their presence in food supplements, neither compound has appropriately been assessed for safety and efficacy. The reported method allows the gram scale isolation of these compounds, opening ways to their in-depth pharmacological investigation.
Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Commelinaceae/química , Ecdisteroides/isolamento & purificação , Extratos Vegetais/química , Acetatos/química , Centrifugação/métodos , Cromatografia de Fase Reversa/métodos , Ecdisteroides/análise , Hexanos/química , Metanol/química , Solventes/químicaRESUMO
Phytoecdysteroids like 20-hydroxyecdysone ("ecdysterone") can exert a mild, non-hormonal anabolic/adaptogenic activity in mammals, and as such, are frequently used in food supplements. Spinach is well-known for its relatively low ecdysteroid content. Cyanotis arachnoidea, a plant native in China, is among the richest sources of phytoecdysteroids, and extracts of this plant are marketed in tons per year amounts via the internet at highly competitive prices. Here we report the investigation of a series of food supplements produced in Germany and claimed to contain spinach extracts. Twelve ecdysteroids including two new compounds were isolated and utilized as marker compounds. A comparative analysis of the products with Cyanotis and spinach extracts provides evidence that they were manufactured from Cyanotis extracts instead of spinach as stated. Based on the chromatographic fingerprints, 20-hydroxyecdysone 2- and 3-acetate are suggested as diagnostic markers for related quality control. This case appears to represent an unusual type of dietary supplement counterfeiting: undeclared extracts from alternative plants would supposedly 'guarantee' product efficacy.
Assuntos
Commelinaceae/química , Suplementos Nutricionais/normas , Ecdisteroides/análise , Spinacia oleracea/química , Animais , China , Ecdisona/análise , Ecdisona/isolamento & purificação , Ecdisteroides/isolamento & purificação , Ecdisterona/análise , Ecdisterona/isolamento & purificação , Alemanha , Fitosteróis/análise , Fitosteróis/isolamento & purificação , Extratos Vegetais/química , Controle de QualidadeRESUMO
The objective of this study was to evaluate the effects of supplementation of phytoecdysteroids (PEDS) extracted from Cyanotis arachnoidea on rumen fermentation, enzymes activity and microbial efficiency in a dual flow continuous-culture system. A single-factor experimental design was used with twelve fermenters in 4 groups with 3 replicates each. Fermenters were incubated for a total of 7 days that included first 4 days for adaptation and last 3 days for sampling. PEDS was added at levels of zero (as control), 5, 10, and 15 mg/g of the substrate (DM). The results showed that increasing supplementation levels of PEDS resulted in incremental digestibility of dry matter (DMD) (quadratic, P = 0.001) and organic matter (OMD) (quadratic, P = 0.031), but unchanged digestibility of neutral detergent fiber (NDFD), crude protein (CPD) and acid detergent acid (ADFD). As supplementation levels of PEDS increased, there were decreased response in the concentration of ammonia nitrogen (NH3-N) (linear, P = 0.015) and increased response in molar proportions of butyrate (linear, P = 0.004), but unchanged response in total volatile fatty acid (TVFA) and the molar proportion of acetate and propionate, respectively. Increasing PEDS supplementation levels decreased the ratio of acetate to propionate (linear, P = 0.038), suggesting an alteration of rumen fermentation pattern occurring due to PEDS supplementation in the diet. Supplementation of PEDS significantly increased activities of glutamate dehydrogenase (quadratic, P = 0.001), alanine dehydrogenase (quadratic, P = 0.004), glutamate synthase (linear, P = 0.038), glutamine synthetase (quadratic, P = 0.011), respectively. There were no discernible differences in the activity of carboxymethyl cellulose (CMCase), xylanase and protease regardless of the treatments. The daily production of microbial nitrogen (linear, P = 0.002) and microbial efficiency (MOEEF) (linear, P = 0.001) increased linearly as supplementation levels of PEDS increased. The decreased response of fluid NH3-N and the increased response of MN indicated that PEDS positively increased the synthesis of microbial proteins.
Assuntos
Bactérias/metabolismo , Commelinaceae/química , Técnicas de Cultura/métodos , Ecdisteroides/farmacologia , Enzimas/metabolismo , Fermentação/efeitos dos fármacos , Rúmen/metabolismo , Ração Animal , Fenômenos Fisiológicos da Nutrição Animal/efeitos dos fármacos , Animais , Bactérias/citologia , Bactérias/efeitos dos fármacos , Reatores Biológicos/microbiologia , Bovinos , Ecdisteroides/isolamento & purificação , Microbioma Gastrointestinal/efeitos dos fármacos , Microbioma Gastrointestinal/fisiologia , Fitosteróis/isolamento & purificação , Fitosteróis/farmacologia , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Rúmen/efeitos dos fármacos , Rúmen/microbiologiaRESUMO
Calcium oxalate (CaOx) crystals in higher plants occur in five forms: raphides, styloids, prisms, druses, and crystal sand. CaOx crystals are formed in almost all tissues in intravacuolar crystal chambers. However, the mechanism of crystallization and the role of CaOx crystals have not been clearly explained. The aim of this study was to explore the occurrence and location of CaOx crystals in organs of Tinantia anomala (Torr.) C.B. Clarke (Commelinaceae) with special attention to ultrastructural changes in the quantity of tapetal raphides during microsporogenesis. We observed various parts of the plant, that is, stems, leaves, sepals, petals, anthers, staminal trichomes and stigmatic papillae and identified CaOx crystals in all parts except staminal trichomes and stigmatic papillae in Tinantia anomala. Three morphological forms: styloids, raphides and prisms were found in different amounts in different parts of the plant. Furthermore, in this species, we identified tapetal raphides in anthers. The number of tapetal raphides changed during microsporogenesis. At the beginning of meiosis, the biosynthesis of raphides proceeded intensively in the provacuoles. These organelles were formed from the endoplasmic reticulum system. In the tetrad stage, we observed vacuoles with needle-shaped raphides (type I) always localised in the centre of the organelle. When the amoeboid tapetum was degenerating, vacuoles also began to fade. We observed a small number of raphides in the stage of mature pollen grains.
Assuntos
Oxalato de Cálcio/metabolismo , Commelinaceae/crescimento & desenvolvimento , Commelinaceae/ultraestrutura , Flores/crescimento & desenvolvimento , Flores/ultraestrutura , Cristalização , Gametogênese Vegetal , Pólen/crescimento & desenvolvimento , Pólen/ultraestruturaRESUMO
RESUMO O objetivo deste estudo foi avaliar o efeito antibacteriano e tripanocida in vitro do extrato hidroalcóolico das raízes de Tradescantia sillamontana Matuda (Commelinaceae), conhecida popularmente como veludo branco. Foi avaliada a atividade antibacteriana in vitro frente às bactérias Streptococcus mitis (CIM = 100 µg/mL; CMB = 150 µg/mL), Streptococcus mutans (CIM = 200 µg/mL; CMB = 220 µg/mL), Streptococcus sanguinis (CIM = 400 µg/mL; CMB = 425 µg/mL), Streptococcus sobrinus (CIM = 400 µg/mL; CMB = 420 µg/mL) e Bacteroides fragilis (CIM = 400 µg/mL; CMB = 430 µg/mL) pelo método de diluição em caldo. Os protozoários da família tripanossomatídeo causam doenças tropicais que costumam ser negligenciadas que costumam ser como a tripanossomíase, para a qual estão disponíveis poucos medicamentos. Neste contexto, o extrato hidroalcóolico das raízes de T. sillamontana também foi avaliado frente às formas tripomastigotas da cepa Y de Trypanosoma cruzi, com promissora atividade frente a este protozoário (IC50 = 2,4 µg/mL). Quando avaliada a atividade citotóxica frente a fibroblastos da linhagem LLCMK2, o extrato apresentou moderada citotoxicidade (CC50 = 480,37 µg/mL). Os resultados ora apresentados para o extrato hidroalcóolico das raízes de Tradescantia sillamontana Matuda demonstraram promissoras atividades antibacteriana e tripanocida, sendo uma fonte alternativa de produtos naturais com atividades contra T. cruzi e algumas bactérias do gênero Streptococcus e Bacteroides.
ABSTRACT The aim of this study was to investigate the in vitro, antibacterial and trypanocidal effect of the hydroalcoholic extract from the roots of Tradescantia sillamontana Matuda (Commelinaceae), commonly known as Veludo branco. The in vitro antibacterial activity against the standard bacteria Streptococcus mitis (MIC = 100µg/mL; MBC = 150 µg/mL), Streptococcus mutans (MIC = 200µg/mL; MBC = 220 µg/mL), Streptococcus sanguinis (MIC = 400µg/mL; MBC = 425 µg/mL), Streptococcus sobrinus (MIC = 400µg/mL; MBC = 420 µg/mL) andBacteroides fragilis (MIC = 400µg/mL; MBC = 430 µg/mL), using microdilution broth methods. Protozoans from the trypanosomatid family cause neglected tropical diseases such as trypanosomiasis, for which few drugs are available. In this context, the hydroalcoholic extract of the Tradescantia sillamontana roots was also investigated with regards to the in vitro effects against the trypomastigote forms of theY strain of Trypanosoma cruzi, showing strong activity against this parasite (IC50 = 2.4 µg/mL). When performing cytotoxic activity against fibroblasts LLCMK2 line, the extract showed moderate cytotoxicity (CC50 = 480.37 mg/mL). The results presented for the hydroalcoholic extract of the roots of Tradescantia sillamontana Matuda demonstrated effective antibacterial and trypanocidal activities and were shown to be an alternative source of natural products with activity against T. cruzi and some bacteria of the genus Streptococcus and Bacteroides.
Assuntos
Tripanossomicidas/análise , Raízes de Plantas/classificação , Tradescantia/classificação , /análise , Antibacterianos/análise , Commelinaceae/classificaçãoRESUMO
Increasing the activation of protein kinase B (Akt) has been suggested as a key signaling step in the nonhormonal anabolic activity of the phytoecdysteroid 20-hydroxyecdysone (20E) in mammals. Base-catalyzed autoxidation of this compound was shown previously to yield interesting B-ring-modified analogues. Herein is reported a thorough study on this reaction, resulting in the preparation and complete NMR spectroscopic assignments of calonysterone (5) and its previously overlooked desmotropic pair (7), along with two new sensitive metabolites of 20E. The two isomers showed considerable stability in solution. Time dependency of the reaction for yield optimization is also presented; by means of analytical HPLC, the two desmotropes can reach a maximum combined yield of >90%. The activity of these compounds on Akt phosphorylation was tested in murine skeletal muscle cells. Compounds 2 and 5 showed more potent activity than 20E in increasing Akt activation, while compound 7 exerted an opposite effect. As such, the present study provides the first direct evidence for a pair of desmotropes exerting significantly different bioactivities.
Assuntos
Commelinaceae/química , Medicamentos de Ervas Chinesas/química , Ecdisterona/metabolismo , Músculo Esquelético/metabolismo , Animais , Cromatografia Líquida de Alta Pressão , Medicamentos de Ervas Chinesas/isolamento & purificação , Medicamentos de Ervas Chinesas/farmacologia , Ecdisterona/isolamento & purificação , Camundongos , Estrutura Molecular , Fibras Musculares Esqueléticas/metabolismo , Músculo Esquelético/efeitos dos fármacos , Oxirredução , Fosforilação , Raízes de Plantas/química , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de SinaisRESUMO
BACKGROUND: Allicin (diallylthiosulfinate) is the major volatile- and antimicrobial substance produced by garlic cells upon wounding. We tested the hypothesis that allicin affects membrane function and investigated 1) betanine pigment leakage from beetroot (Beta vulgaris) tissue, 2) the semipermeability of the vacuolar membrane of Rhoeo discolor cells, 3) the electrophysiology of plasmalemma and tonoplast of Chara corallina and 4) electrical conductivity of artificial lipid bilayers. METHODS: Garlic juice and chemically synthesized allicin were used and betanine loss into the medium was monitored spectrophotometrically. Rhoeo cells were studied microscopically and Chara- and artificial membranes were patch clamped. RESULTS: Beet cell membranes were approximately 200-fold more sensitive to allicin on a mol-for-mol basis than to dimethyl sulfoxide (DMSO) and approximately 400-fold more sensitive to allicin than to ethanol. Allicin-treated Rhoeo discolor cells lost the ability to plasmolyse in an osmoticum, confirming that their membranes had lost semipermeability after allicin treatment. Furthermore, allicin and garlic juice diluted in artificial pond water caused an immediate strong depolarization, and a decrease in membrane resistance at the plasmalemma of Chara, and caused pore formation in the tonoplast and artificial lipid bilayers. CONCLUSIONS: Allicin increases the permeability of membranes. GENERAL SIGNIFICANCE: Since garlic is a common foodstuff the physiological effects of its constituents are important. Allicin's ability to permeabilize cell membranes may contribute to its antimicrobial activity independently of its activity as a thiol reagent.
Assuntos
Beta vulgaris/efeitos dos fármacos , Chara/efeitos dos fármacos , Commelinaceae/efeitos dos fármacos , Alho/química , Bicamadas Lipídicas/metabolismo , Ácidos Sulfínicos/farmacologia , Beta vulgaris/metabolismo , Permeabilidade da Membrana Celular/efeitos dos fármacos , Chara/metabolismo , Commelinaceae/metabolismo , Dimetil Sulfóxido/farmacologia , Dissulfetos , Pigmentos Biológicos/metabolismo , Ácidos Sulfínicos/farmacocinéticaRESUMO
Keloids are characterised by the excessive accumulation of extracellular matrix (ECM), especially overabundant collagen formation. In keloid fibroblasts (KFs), transforming growth factor (TGF)-ß-dependent signalling is closely associated with a variety of keloid pathologic responses such as ECM production and fibroblast overgrowth. Thus, inhibition of TGF-ß signalling would be a potential therapeutic approach to prevent keloid scar formation. Thereby, we aimed to identify a novel TGF-ß signalling blocker among natural products using a simplified screening approach. We discovered that the extract of Aneilema keisak (A.K-Ex) lowered TGF-ß-dependent signalling by reducing Smad2 protein levels. Given that KFs showed altered dependency on TGF-ß for survival and proliferation, A.K-Ex-mediated reduction in Smad2 protein levels significantly inhibited the major characteristics of KFs such as cell growth, migration and collagen synthesis, suggesting that A.K-Ex exhibits possible therapeutic activity on keloids.