Your browser doesn't support javascript.
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 73
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
Zhongguo Zhong Yao Za Zhi ; 45(1): 85-91, 2020 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-32237415

RESUMO

Polygonatum cyrtonema belongs to the plant family Liliaceae, and its dried rhizome is one of the sources of Chinese traditional medicine of Polygonati Rhizoma. It possesses the dual function as both medicine and food. Its main chemical components are polysaccharides and saponins. In order to understand the biosynthesis pathway of polysaccharides and diosgenin in P. cyrtonema, the corresponding transcriptomic data were obtained by extracting and sequencing the RNA of four parts of P. cyrtonema, namely, leaves, stems, rhizomes and roots. By adopting BGISEQ-500 sequencing platform, 42.03 Gb data were retrieved. Subsequently, the de novo assembly was carried out by Trinity software to obtain 137 233 transcripts, of which 68.13% of unigenes were annotated in seven databases including KEGG, GO, NR, NT, SwissProt, Pfam and KOG. Transcripts that may be involved in the biosynthesis of polysaccharides and diosgenin were analyzed by data mining. With help of qPCR, we validated expression data of four genes that were possibly involved in the biosynthesis of target metabolites. This experiment provides data for the study of biosynthetic pathways of P. cyrtonema secondary metabolites and the clarification of related structural gene functions.


Assuntos
Diosgenina/metabolismo , Polygonatum/metabolismo , Polissacarídeos/biossíntese , Transcriptoma , Vias Biossintéticas , Perfilação da Expressão Gênica , Compostos Fitoquímicos/biossíntese , Polygonatum/genética
2.
Zhonghua Wei Zhong Bing Ji Jiu Yi Xue ; 31(6): 746-749, 2019 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-31315735

RESUMO

OBJECTIVE: To investigate the protective effect of Polyphyllin I (PPI) on myocardial ischemia/reperfusion (I/R) injury in rats and its mechanism. METHODS: The 6-month-old Sprague-Dawley (SD) rats were divided into sham operation group (Sham group), I/R model group, and low, medium, high dose PPI groups according to the random number table method, with 10 in each group. The rat myocardial I/R model was prepared by ligating the left anterior descending branch of the coronary artery by 30 minutes and reperfusion by 120 minutes. Sham group was exposure to open chest without ligation. Low, medium, high dose PPI groups were injected with PPI 75, 150, 300 mg×kg-1×d-1 in front of the film for 4 weeks; dimethyl sulfoxide (DMSO) was gastric infused in the I/R model group. After the end of reperfusion, the myocardial infarction area (IA) was determined by triphenyltetrazole (TTC) and Evans blue (EB) staining; the apoptosis of myocardial cells was detected by TdT-mediated dUTP nick end labeling stain (TUNEL); the expressions of apoptosis related protein (Bax, Bcl-2), and cytoplasmic and nucleus expressions of P65 in nuclear factor-ΚB (NF-ΚB) signal pathway were detected by Western Blot. RESULTS: Compared with the Sham group, the myocardial IA was significantly increased in the I/R model group, the apoptosis rate of myocardial cells was significantly increased, the expression of Bcl-2 was significantly decreased, and the expression of Bax was significantly increased, and the intranuclear transfer of P65 was significantly increased. Compared with the I/R model group, low, medium and high dose PPI pretreatment could significantly reduce the myocardial IA [(21.6±0.9)%, (14.3±1.6)%, (15.0±0.8)% vs. (29.6±1.4)%], the apoptosis rate of myocardial cells was significantly decreased [(38.6±1.9)%, (24.3±2.6)%, (26.3±2.8)% vs. (56.8±2.4)%], the protein expression of Bcl-2 was significantly increased, while the protein expression of Bax was significantly decreased (Bcl-2/GAPDH: 0.24±0.07, 0.36±0.02, 0.34±0.09 vs. 0.13±0.04; Bax/GAPDH: 0.39±0.10, 0.21±0.08, 0.23±0.06 vs. 0.53±0.12); and P65 nuclear transfer was significantly decreased after middle and high dose PPI pretreatment [nuclear P65/Histone 3: 0.49±0.09, 0.51±0.06 vs. 0.83±0.11; cytoplasmic P65/GAPDH: 0.31±0.03, 0.30±0.05 vs. 0.22±0.07], with statistically significant differences (all P < 0.05). However, there was no significant difference in each index between the medium and high dose PPI groups (all P > 0.05). CONCLUSIONS: PPI alleviates myocardial I/R injury in rats via NF-ΚB signal pathway, and the PPI effect of 150 mg×kg-1×d-1 is most especially significant.


Assuntos
Diosgenina/análogos & derivados , Isquemia Miocárdica/prevenção & controle , Traumatismo por Reperfusão Miocárdica/prevenção & controle , NF-kappa B/metabolismo , Transdução de Sinais , Animais , Apoptose , Diosgenina/metabolismo , Modelos Animais de Doenças , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley
3.
Food Chem ; 298: 125063, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31260979

RESUMO

Dioscorea opposita Thunb. cv. Tiegun (DTT), a type of homologous medicinal plant, is commonly used as food in daily life. However, there has always been confusion regarding removal of the peel, as the nutrient metabolite composition of the peel is unclear. Here, a nuclear magnetic resonance (NMR)-based metabolomics approach was used to determine the metabolite distribution in DTT exclude-peel and peel. Thirteen characteristic metabolites with statistical significance were identified and compared using multivariate, univariate and cluster analyses. The results demonstrated that the peel contained the higher levels of α-glucose, batatasin IV, batatasin I, asparagine, ß-glucose, protodioscin, threonine, protogracillin, dioscin, and ß-sitosteryl acetate, and the samples without the peel had the higher levels of leucine, glutamine and alanine. This study provided scientific data for understanding the distribution characteristics of metabolites in DTT samples, promoting reasonable consumption of DTT.


Assuntos
Dioscorea/metabolismo , Metabolômica/métodos , Análise por Conglomerados , Diosgenina/análogos & derivados , Diosgenina/química , Diosgenina/metabolismo , Leucina/metabolismo , Espectroscopia de Ressonância Magnética , Exsudatos de Plantas/metabolismo , Plantas Medicinais/metabolismo , Análise de Componente Principal , Saponinas/química , Saponinas/metabolismo
4.
Nat Commun ; 10(1): 3206, 2019 07 19.
Artigo em Inglês | MEDLINE | ID: mdl-31324795

RESUMO

Diosgenin is a spiroketal steroidal natural product extracted from plants and used as the single most important precursor for the world steroid hormone industry. The sporadic occurrences of diosgenin in distantly related plants imply possible independent biosynthetic origins. The characteristic 5,6-spiroketal moiety in diosgenin is reminiscent of the spiroketal moiety present in anthelmintic avermectins isolated from actinomycete bacteria. How plants gained the ability to biosynthesize spiroketal natural products is unknown. Here, we report the diosgenin-biosynthetic pathways in himalayan paris (Paris polyphylla), a monocot medicinal plant with hemostatic and antibacterial properties, and fenugreek (Trigonella foenum-graecum), an eudicot culinary herb plant commonly used as a galactagogue. Both plants have independently recruited pairs of cytochromes P450 that catalyze oxidative 5,6-spiroketalization of cholesterol to produce diosgenin, with evolutionary progenitors traced to conserved phytohormone metabolism. This study paves the way for engineering the production of diosgenin and derived analogs in heterologous hosts.


Assuntos
Vias Biossintéticas , Sistema Enzimático do Citocromo P-450/metabolismo , Diosgenina/metabolismo , Furanos/metabolismo , Lipogênese/fisiologia , Compostos de Espiro/metabolismo , Antibacterianos , Colesterol/metabolismo , Citocromos/metabolismo , Galactagogos , Perfilação da Expressão Gênica , Ivermectina/análogos & derivados , Melanthiaceae/química , Metabolômica , Reguladores de Crescimento de Planta/metabolismo , Trigonella
5.
Molecules ; 24(1)2019 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-30609669

RESUMO

Trigonella foenum-graecum L. (fenugreek) is a valuable resource of producing diosgenin which serves as a substrate for synthesizing more than two hundred kinds of steroidal drugs. Phytochemical analysis indicated that methyl jasmonate (MeJA) efficiently induced diosgenin biosynthesis in fenugreek seedlings. Though early steps up to cholesterol have recently been elucidated in plants, cytochrome P450 (CYP)- and glycosyltransferase (GT)-encoding genes involved in the late steps from cholesterol to diosgenin remain unknown. This study established comparative fenugreek transcriptome datasets from the MeJA-treated seedlings and the corresponding control lines. Differential gene expression analysis identified a number of MeJA-induced CYP and GT candidate genes. Further gene expression pattern analysis across a different MeJA-treating time points, together with a phylogenetic analysis, suggested specific family members of CYPs and GTs that may participate in the late steps during diosgenin biosynthesis. MeJA-induced transcription factors (TFs) that may play regulatory roles in diosgenin biosynthesis were also discussed. This study provided a valuable genetic resource to functionally characterize the genes involved in diosgenin biosynthesis, which will push forward the production of diosgenin in microbial organisms using a promising synthetic biology strategy.


Assuntos
Diosgenina/metabolismo , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Transcriptoma , Trigonella/genética , Trigonella/metabolismo , Biologia Computacional/métodos , Ontologia Genética , Redes e Vias Metabólicas , Anotação de Sequência Molecular , Filogenia , Fatores de Transcrição , Trigonella/classificação
6.
Biointerphases ; 13(6): 061001, 2018 11 08.
Artigo em Inglês | MEDLINE | ID: mdl-30408964

RESUMO

The purpose of this study was to investigate the interaction between diosgenin analogues [DioA: diosgenin acetate (DAc) and (25R)-5α,6ß-dihydroxyspirostan-3ß-ol acetate (DSol)] and cholesterol (Ch) monolayers at the air/water interface. The surface tension of pure and mixed lipid monolayers at 22 °C was measured by using the Langmuir method with a Teflon trough and a Nima 9002 tensiometer. The surface tension values were used to calculate the π-A isotherms and to determine the molecular surface areas. The interactions between Ch and each DioA resulted in significant deviations from the additivity rule. The theory described in this work was used to determine the stability constants, the areas occupied by one molecule of Ch-DAc or Ch-DSol, and the complex formation energy (Gibbs free energy) values.


Assuntos
Colesterol/metabolismo , Diosgenina/análogos & derivados , Diosgenina/metabolismo , Membranas Artificiais , Colesterol/química , Tensão Superficial , Temperatura
7.
J Asian Nat Prod Res ; 20(7): 624-632, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29732923

RESUMO

Three new (6, 9, and 12) and nine known steroidal saponins were obtained from the fermentation broth of pseudoprotodioscin (PPD) incubated with a fungus Gibberella fujikuroi CGMCC 3.4663. Structures of the metabolites were elucidated by 1-D (1H, 13C), 2-D (HMBC, HSQC, NOESY) NMR, and HR-MS analyses. The biotransformation pathway of pseudoprotodioscin by Gibberella fujikuroi CGMCC 3.4663 was proposed. Compounds 1-11 were tested in vitro for their cytotoxic activities against two human cancer cell lines (HepG2 and Hela). Compounds 1, 6, 9, and 10 exhibited cytotoxic activity against HepG2 cells. Compound 10 exhibited cytotoxicity to Hela cells.


Assuntos
Diosgenina/análogos & derivados , Gibberella/metabolismo , Antibióticos Antineoplásicos/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Diosgenina/química , Diosgenina/metabolismo , Diosgenina/farmacologia , Gibberella/química , Células HeLa , Células Hep G2 , Humanos , Espectroscopia de Ressonância Magnética , Espectrometria de Massas , Estrutura Molecular
8.
Appl Environ Microbiol ; 84(14)2018 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-29728384

RESUMO

3-Ketosteroid 9α-hydroxylase (Ksh) consists of a terminal oxygenase (KshA) and a ferredoxin reductase and is indispensable in the cleavage of steroid nucleus in microorganisms. The activities of Kshs are crucial factors in determining the yield and distribution of products in the biotechnological transformation of sterols in industrial applications. In this study, two KshA homologues, KshA1N and KshA2N, were characterized and further engineered in a sterol-digesting strain, Mycobacterium neoaurum ATCC 25795, to construct androstenone-producing strains. kshA1 N is a member of the gene cluster encoding sterol catabolism enzymes, and its transcription exhibited a 4.7-fold increase under cholesterol induction. Furthermore, null mutation of kshA1 N led to the stable accumulation of androst-4-ene-3,17-dione (AD) and androst-1,4-diene-3,17-dione (ADD). We determined kshA2 N to be a redundant form of kshA1 N Through a combined modification of kshA1 N, kshA2 N, and other key genes involved in the metabolism of sterols, we constructed a high-yield ADD-producing strain that could produce 9.36 g liter-1 ADD from the transformation of 20 g liter-1 phytosterols in 168 h. Moreover, we improved a previously established 9α-hydroxy-AD-producing strain via the overexpression of a mutant KshA1N that had enhanced Ksh activity. Genetic engineering allowed the new strain to produce 11.7 g liter-1 9α-hydroxy-4-androstene-3,17-dione (9-OHAD) from the transformation of 20.0 g liter-1 phytosterol in 120 h.IMPORTANCE Steroidal drugs are widely used for anti-inflammation, anti-tumor action, endocrine regulation, and fertility management, among other uses. The two main starting materials for the industrial synthesis of steroid drugs are phytosterol and diosgenin. The phytosterol processing is carried out by microbial transformation, which is thought to be superior to the diosgenin processing by chemical conversions, given its simple and environmentally friendly process. However, diosgenin has long been used as the primary starting material instead of phytosterol. This is in response to challenges in developing efficient microbial strains for industrial phytosterol transformation, which stem from complex metabolic processes that feature many currently unclear details. In this study, we identified two oxygenase homologues of 3-ketosteroid-9α-hydroxylase, KshA1N and KshA2N, in M. neoaurum and demonstrated their crucial role in determining the yield and variety of products from phytosterol transformation. This work has practical value in developing industrial strains for phytosterol biotransformation.


Assuntos
Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Oxigenases de Função Mista/genética , Mycobacterium/genética , Mycobacterium/metabolismo , Esteroides/metabolismo , Substituição de Aminoácidos , Androstadienos/metabolismo , Biotransformação , Colesterol , Diosgenina/metabolismo , Deleção de Genes , Engenharia Genética/métodos , Redes e Vias Metabólicas/genética , Modelos Moleculares , Mutagênese Sítio-Dirigida , Micobactérias não Tuberculosas/genética , Micobactérias não Tuberculosas/metabolismo , Oxigenases/metabolismo , Fitosteróis/metabolismo , Alinhamento de Sequência , Análise de Sequência de Proteína
9.
Appl Microbiol Biotechnol ; 102(13): 5519-5532, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29725718

RESUMO

In this study, endophytic fungi were isolated from Dioscorea zingiberensis C.H. Wright (DZW), and a novel clean process to prepare diosgenin from DZW was developed. A total of 123 strains of endophytic fungi were isolated from different plant tissues of DZW. Among them, the strain Fusarium sp. (CPCC 400709) showed the best activity of hydrolyzing steroidal saponins in DZW into diosgenin. Thus, this strain was used to prepare diosgenin from DZW by solid-state fermentation. The fermentation parameters were optimized using response surface methodology, and a high yield of diosgenin (2.16%) was obtained at 14.5% ammonium sulfate, an inoculum size of 12.3%, and 22 days of fermentation. Furthermore, the highest diosgenin yield (2.79%) was obtained by co-fermentation with Fusarium sp. (CPCC 400709) and Curvularia lunata (CPCC 400737), which was 98.9% of that obtained by ß-glucosidase pretreated acid hydrolysis (2.82%). This process is acid-free and wastewater-free, and shows promise as an effective and clean way to prepare diosgenin for use in industrial applications from DZW.


Assuntos
Dioscorea/microbiologia , Diosgenina/metabolismo , Fermentação , Fusarium/isolamento & purificação , Fusarium/metabolismo , Microbiologia Industrial , Hidrólise , Saponinas/metabolismo
10.
Steroids ; 136: 40-46, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29750996

RESUMO

A novel microbial procedure was proposed for diosgenin production from Dioscorea zingiberensis C.H. Wright (DZW) tubers via employing Aspergillus awamori for the first time. The optimal conditions of fermenter cultivation were established as inoculation dosage of 8%, fermentation temperature of 30 °C, cultivation time of 8 days, initial pH of 7.0 and a stirring rate of 180 rpm when the converted diosgenin content reached a peak value of 74.26 ±â€¯3.23 mg/g substrate. The product was purified by silica gel column and then confirmed as diosgenin (purity: 96.9 ±â€¯2.42%) by nuclear magnetic resonance (NMR). Compared with traditional acid hydrolysis, this new process generated indeed less wastewater with lower chemical oxygen demand (COD) reduced to 500 mg/L from 10,000 mg/L and absence of acid and alkali. This research provided definitely an environmental and high-efficiency microbial technology for diosgenin production.


Assuntos
Aspergillus/metabolismo , Biotecnologia , Dioscorea/química , Diosgenina/metabolismo , Fermentação , Tubérculos/química , Saponinas/metabolismo , Química Verde , Hidrólise , Temperatura
11.
Eur J Drug Metab Pharmacokinet ; 43(5): 587-597, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29589340

RESUMO

BACKGROUND AND OBJECTIVES: Protein-calorie malnutrition (PCM) is one of the most suffered complications in cancer patients. Polyphyllin I (PPI), a saponin isolated from rhizome of Paris polyphylla, is a potential candidate in cancer therapy. In this study, the influence of nutritional status on the absorption of PPI in rats was explored after oral administration. METHODS: PCM rats, namely mal-nourished (MN) rats, were induced from well-nourished (WN) rats by caloric restriction protocol. Intestinal absorption of PPI in WN and MN rats was evaluated by pharmacokinetic and intestinal perfusion methods. The potential mechanisms between two groups were investigated on the basis of intestinal permeability, intestinal efflux and PPI's depletions in vivo. The intestinal permeability was analyzed by determining the concentration of paracellular marker transport in serum and the expression of junction proteins in intestine. The intestinal efflux was evaluated through comparing the protein level of P-glycoprotein (P-gp) in intestine, and the depletions of PPI and/or generation of its metabolites in liver and intestines were analyzed by liquid chromatography triple quadrupole mass spectrometry (LC-MS/MS) method. RESULTS: Compared to WN rats, the oral systemic exposure of PPI was significantly increased in MN rats, evidenced by significant enhancement of maximum plasma concentration (Cmax) and area under the plasma concentration-time curve (AUC0-60h) by more than 2.51- and 3.71-folds as well as terminal elimination half-life (t1/2) prolonged from to 7.3 to 14.1 h. Further studies revealed that the potential mechanism might be associated with combined contribution of improved intestinal absorption and depressed deglycosylation of PPI in MN rats. Furthermore, enhanced intestinal absorption of PPI was benefited from increased intestinal permeability and decreased intestinal efflux in MN rats. Meanwhile, the former manifested as increased transport of paracellular marker and decreased junction proteins levels, while the later evidenced by reduced P-gp expression. CONCLUSIONS: The oral exposure of PPI was enhanced in MN rats, which suggested that nutritional status alters the absorption of PPI, and thus the dosage of PPI should be modified during the treatment of cancer patient with PCM.


Assuntos
Antineoplásicos Fitogênicos/metabolismo , Diosgenina/análogos & derivados , Absorção Intestinal , Intestino Delgado/metabolismo , Liliaceae , Estado Nutricional , Desnutrição Proteico-Calórica/metabolismo , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/metabolismo , Administração Oral , Fenômenos Fisiológicos da Nutrição Animal , Animais , Antineoplásicos Fitogênicos/administração & dosagem , Antineoplásicos Fitogênicos/isolamento & purificação , Antineoplásicos Fitogênicos/farmacocinética , Biotransformação , Diosgenina/administração & dosagem , Diosgenina/isolamento & purificação , Diosgenina/metabolismo , Diosgenina/farmacocinética , Modelos Animais de Doenças , Intestino Delgado/fisiopatologia , Liliaceae/química , Fígado/metabolismo , Masculino , Modelos Biológicos , Permeabilidade , Desnutrição Proteico-Calórica/fisiopatologia , Ratos Sprague-Dawley , Rizoma , Junções Íntimas/metabolismo
12.
Molecules ; 23(2)2018 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-29463020

RESUMO

Dioscorea zingiberensis is a perennial herb native to China. The rhizome of D. zingiberensis has long been used as a traditional Chinese medicine to treat rheumatic arthritis. Dioscin is the major bioactive ingredient conferring the medicinal property described in Chinese pharmacopoeia. Several previous studies have suggested cholesterol as the intermediate to the biosynthesis of dioscin, however, the biosynthetic steps to dioscin after cholesterol remain unknown. In this study, a comprehensive D. zingiberensis transcriptome derived from its leaf and rhizome was constructed. Based on the annotation using various public databases, all possible enzymes in the biosynthetic steps to cholesterol were identified. In the late steps beyond cholesterol, cholesterol undergoes site-specific oxidation by cytochrome P450s (CYPs) and glycosylation by UDP-glycosyltransferases (UGTs) to yield dioscin. From the D. zingiberensis transcriptome, a total of 485 unigenes were annotated as CYPs and 195 unigenes with a sequence length above 1000 bp were annotated as UGTs. Transcriptomic comparison revealed 165 CYP annotated unigenes correlating to dioscin biosynthesis in the plant. Further phylogenetic analysis suggested that among those CYP candidates four of them would be the most likely candidates involved in the biosynthetic steps from cholesterol to dioscin. Additionally, from the UGT annotated unigenes, six of them were annotated as 3-O-UGTs and two of them were annotated as rhamnosyltransferases, which consisted of potential UGT candidates involved in dioscin biosynthesis. To further explore the function of the UGT candidates, two 3-O-UGT candidates, named Dz3GT1 and Dz3GT2, were cloned and functionally characterized. Both Dz3GT1 and Dz3GT2 were able to catalyze a C3-glucosylation activity on diosgenin. In conclusion, this study will facilitate our understanding of dioscin biosynthesis pathway and provides a basis for further mining the genes involved in dioscin biosynthesis.


Assuntos
Dioscorea/genética , Diosgenina/análogos & derivados , Perfilação da Expressão Gênica/métodos , Transcriptoma/genética , China , Sistema Enzimático do Citocromo P-450/química , Sistema Enzimático do Citocromo P-450/genética , Dioscorea/química , Diosgenina/química , Diosgenina/metabolismo , Anotação de Sequência Molecular , Filogenia , Rizoma/genética
13.
Nat Prod Res ; 32(15): 1809-1816, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29172707

RESUMO

The present investigation reports the growth kinetics and diosgenin accumulation in callus cultures of Costus speciosus. Effect of explants, media and plant growth regulators was evaluated with respect to callus induction and growth. Out of the two explants viz pseudostem and seed, pseudostem showed maximum callus induction frequency of 90% on MS medium. The fresh weight of callus was maximum (9-folds) on 28th day on 1.0 mg/L picloram containing medium. The callus obtained was white compact hard (WCH). For growth kinetics study pseudostem derived callus was transferred on different media supplemented with 1.0 mg/L picloram. All phases of growth were seen in callus inoculated on all the three media except the absence of stationary phase on MS and SH media. MS medium proved to be the best for maximum biomass accumulation (9-fold) on 28th day of culture and callus in post-exponential phase showed maximum diosgenin accumulation (33 ppm).


Assuntos
Costus/citologia , Costus/crescimento & desenvolvimento , Diosgenina/metabolismo , Técnicas de Cultura de Células , Costus/metabolismo , Meios de Cultura , Cinética , Reguladores de Crescimento de Planta/farmacologia , Sementes/citologia
14.
J Diabetes Res ; 2017: 7309816, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29038789

RESUMO

OBJECTIVE: To seek efficient aldose reductase inhibitors (ARIs) with excellent in vitro and in vivo biological activities against rat galactosemic cataract. METHODS: The method was firstly optimized to screen strong ARIs from nonoriented synthetic compounds and natural extracts. Then, diosgenin was assessed on osmotic expansion of primarily cultured lens epithelial cells (LECs) induced by galactose (50 mM). Diosgenin was administered to galactosemic rats by oral (100 and 200 mg/kg) or direct drinking (0.1%) to evaluate its anticataract effects. RESULTS: Diosgenin was found as the strongest ARI with IC50 of 4.59 × 10-6 mol/L. Diosgenin (10 µM) evidently inhibited the formation of tiny vacuoles and upregulation of AR mRNA in LECs. In vivo, diosgenin delayed lens opacification, inhibited the increase of ratio of lens weight to body weight, and decreased AR activity, galactitol level, and AR mRNA expression, especially in the diosgenin drinking (0.1%) group. CONCLUSIONS: Diosgenin was an efficient ARI, which not only significantly decreased the LECs' osmotic expansion in vitro but also markedly delayed progression of rat galactosemic cataract in vivo. Thus, diosgenin rich food can be recommended to diabetic subjects as dietary management to postpone the occurrence of sugar cataract, and diosgenin deserves further investigation for chronic diabetic complications.


Assuntos
Aldeído Redutase/antagonistas & inibidores , Catarata/prevenção & controle , Suplementos Nutricionais , Diosgenina/uso terapêutico , Inibidores Enzimáticos/uso terapêutico , Proteínas do Olho/antagonistas & inibidores , Cristalino/metabolismo , Aldeído Redutase/genética , Aldeído Redutase/isolamento & purificação , Aldeído Redutase/metabolismo , Animais , Animais Endogâmicos , Catarata/etiologia , Catarata/metabolismo , Catarata/patologia , Tamanho Celular , Sobrevivência Celular , Células Cultivadas , Dieta da Carga de Carboidratos/efeitos adversos , Diosgenina/administração & dosagem , Diosgenina/metabolismo , Cães , Inibidores Enzimáticos/administração & dosagem , Inibidores Enzimáticos/metabolismo , Proteínas do Olho/genética , Proteínas do Olho/isolamento & purificação , Proteínas do Olho/metabolismo , Galactitol/metabolismo , Galactose/efeitos adversos , Regulação Enzimológica da Expressão Gênica , Cristalino/citologia , Cristalino/patologia , Masculino , RNA Mensageiro/metabolismo , Distribuição Aleatória , Ratos Sprague-Dawley , Vacúolos/patologia
15.
Toxins (Basel) ; 9(7)2017 07 13.
Artigo em Inglês | MEDLINE | ID: mdl-28703748

RESUMO

Protodioscin is used as a marker of saponin content that could cause hepatotoxicity in ruminants. In Brachiaria spp. from two regions of the Colombian Eastern Plains (east mountain range of the Andean-"piedemonte" and Ariari River Valley) were determined this metabolite at 14 and 28 days post-cutting under different climatic conditions. No protodioscin was detected in B. dictyoneura or B. humidicola. In B. brizantha, B. decumbens and B. ruziziensis x B. decumbens x B. brizantha (hybrid), protodioscin content corresponded to an interaction between species, post-cutting time and season. Concentrations ≥1% (minimum toxic level) were recorded in B. decumbens and the hybrid, and to a lesser extent in B. brizantha. The concentration of protodioscin was higher at 28 days, when the pastures are suitable for consumption. B. brizantha accumulated the lowest saponin concentration, whereas the hybrid had the highest levels, particularly in the "piedemonte" and during drought (3.37%). Dry season favored the protodioscin concentration in B. decumbens (in river valley) and in the hybrid (in "piedemonte"). In the latter, there was a positive correlation with temperature and a negative with humidity, which are typical characteristics of dry periods. This is the first report of protodioscin content in the hybrid.


Assuntos
Brachiaria/química , Diosgenina/análogos & derivados , Saponinas/análise , Brachiaria/metabolismo , Colômbia , Diosgenina/análise , Diosgenina/metabolismo , Monitoramento Ambiental , Saponinas/metabolismo , Estações do Ano
16.
Planta ; 245(5): 977-991, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28161815

RESUMO

MAIN CONCLUSION: Representational difference analysis of cDNA was performed and differential products were sequenced and annotated. Candidate genes involved in biosynthesis of diosgenin in fenugreek were identified. Detailed mechanism of diosgenin synthesis was proposed. Fenugreek (Trigonella foenum-graecum L.) is a valuable medicinal and crop plant. It belongs to Fabaceae family and has a unique potential to synthesize valuable steroidal saponins, e.g., diosgenin. Elicitation (methyl jasmonate) and precursor feeding (cholesterol and squalene) were used to enhance the content of sterols and steroidal sapogenins in in vitro grown plants for representational difference analysis of cDNA (cDNA-RDA). To identify candidate genes involved in diosgenin biosynthesis, differential, factor-specific libraries were subject to the next-generation sequencing. Approximately 9.9 million reads were obtained, trimmed, and assembled into 31,491 unigenes with an average length of 291 bp. Then, functional annotation and gene ontogeny enrichment analysis was performed by aligning all-unigenes with public databases. Within the transcripts related to sterol and steroidal saponin biosynthesis, we discovered novel candidate genes of diosgenin biosynthesis and validated their expression using quantitative RT-PCR analysis. Based on these findings, we supported the idea that diosgenin is biosynthesized from cycloartenol via cholesterol. This is the first report on the next-generation sequencing of cDNA-RDA products. Analysis of the transcriptomes enriched in low copy sequences contributed substantially to our understanding of the biochemical pathways of steroid synthesis in fenugreek.


Assuntos
Acetatos/metabolismo , Ciclopentanos/metabolismo , Diosgenina/metabolismo , Oxilipinas/metabolismo , Fitosteróis/metabolismo , Reguladores de Crescimento de Planta/metabolismo , Transcriptoma , Trigonella/genética , DNA Complementar/genética , Sequenciamento de Nucleotídeos em Larga Escala , Análise de Sequência de DNA , Trigonella/metabolismo
17.
Sci Rep ; 7: 40035, 2017 01 06.
Artigo em Inglês | MEDLINE | ID: mdl-28059131

RESUMO

Sepsis, in addition to causing fatality, is an independent risk factor for cognitive impairment among sepsis survivors. The pathologic mechanism of endotoxemia induced acute neuro-inflammation still has not been fully understood. For the first time, we found the disruption of neurotransmitters 5-HT, impaired neurogenesis and activation of astrocytes coupled with concomitant neuro-inflammation were the potential pathogenesis of endotoxemia induced acute neuro-inflammation in sepsis survivors. In addition, dioscin a natural steroidal saponin isolated from Chinese medicinal herbs, enhanced the serotonergic system and produced anti-depressant effect by enhancing 5-HT levels in hippocampus. What is more, this finding was verified by metabolic analyses of hippocampus, indicating 5-HT related metabolic pathway was involved in the pathogenesis of endotoxemia induced acute neuro-inflammation. Moreover, neuro-inflammation and neurogenesis within hippocampus were indexed using quantitative immunofluorescence analysis of GFAP DCX and Ki67, as well as real-time RT-PCR analysis of some gene expression levels in hippocampus. Our in vivo and in vitro studies show dioscin protects hippocampus from endotoxemia induced cascade neuro-inflammation through neurotransmitter 5-HT and HMGB-1/TLR4 signaling pathway, which accounts for the dioscin therapeutic effect in behavioral tests. Therefore, the current findings suggest that dioscin could be a potential approach for the therapy of endotoxemia induced acute neuro-inflammation.


Assuntos
Diosgenina/análogos & derivados , Encefalite/tratamento farmacológico , Endotoxemia/complicações , Neurogênese/efeitos dos fármacos , Agonistas do Receptor de Serotonina/metabolismo , Serotonina/metabolismo , Animais , Diosgenina/metabolismo , Perfilação da Expressão Gênica , Proteína Glial Fibrilar Ácida/análise , Hipocampo/patologia , Hipocampo/fisiologia , Antígeno Ki-67/análise , Camundongos Endogâmicos C57BL , Microscopia de Fluorescência , Proteínas Associadas aos Microtúbulos/análise , Neuropeptídeos/análise , Reação em Cadeia da Polimerase em Tempo Real
18.
AAPS PharmSciTech ; 18(6): 2067-2076, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27995466

RESUMO

Diosgenin (DSG), a well-known steroid sapogenin derived from Dioscorea nipponica Makino and Dioscorea zingiberensis Wright, has a variety of bioactivities. However, it shows low oral bioavailability due to poor aqueous solubility and strong hydrophobicity. The present study aimed to develop DSG nanocrystals to increase the dissolution and then improve the oral bioavailability and biopharmaceutical properties of DSG. DSG nanocrystals were prepared by the media milling method using a combination of pluronic F127 and sodium dodecyl sulfate as surface stabilizers. The physicochemical properties of the optimal DSG nanocrystals were characterized using their particle size distribution, morphology, differential scanning calorimetry, powder X-ray diffraction, Fourier transform infrared spectroscopy data, and solubility and dissolution test results. Pharmacokinetic studies of the DSG coarse suspension and its nanocrystals were performed in rats. The particle size and polydispersity index of DSG nanocrystals were 229.0 ± 3.7 nm and 0.163 ± 0.064, respectively. DSG retained its original crystalline state during the manufacturing process, and its chemical structure was not compromised by the nanonizing process. The dissolution rate of the freeze-dried DSG nanocrystals was significantly improved in comparison with the original DSG. The pharmacokinetic studies showed that the AUC0-72h and C max of DSG nanocrystals increased markedly (p < 0.01) in comparison with the DSG coarse suspension by about 2.55- and 2.01-fold, respectively. The use of optimized nanocrystals is a good and efficient strategy for oral administration of DSG due to the increased dissolution rate and oral bioavailability of DSG nanocrystals.


Assuntos
Diosgenina/síntese química , Diosgenina/metabolismo , Nanopartículas/química , Nanopartículas/metabolismo , Administração Oral , Animais , Disponibilidade Biológica , Varredura Diferencial de Calorimetria/métodos , Diosgenina/administração & dosagem , Avaliação Pré-Clínica de Medicamentos/métodos , Liofilização/métodos , Masculino , Nanopartículas/administração & dosagem , Tamanho da Partícula , Ratos , Ratos Sprague-Dawley , Solubilidade , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Difração de Raios X
19.
J Nat Med ; 71(1): 139-147, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27665608

RESUMO

Paris Polyphylla Smith var. yunnanensis (Franch.) Hand.-Mazz ("Dian Chonglou" in Chinese) is a famous herbal medicine in China, which is usually well known for activities of anti-cancer, hemolysis, and cytotoxicity. In this study, Fourier transform infrared (FT-IR) spectroscopy coupled with principal component analysis (PCA) and partial least-squares regression (PLSR) was applied to discriminate samples of P. polyphylla var. yunnanensis harvested in different years and determine the content of polyphyllin I, II, VI, and VII in P. polyphylla var. yunnanensis. Meanwhile, ultra performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) was used to study the dynamic changes of P. polyphylla var. yunnanensis harvested in different years (4, 5, 7, 8, 9, 12, and 13 years old). According to the UPLC-MS/MS result, the optimum harvest time of P. polyphylla var. yunnanensis is 8 years, due to the highest yield of four active components. By the PCA model, P. polyphylla var. yunnanensis could be exactly discriminated, except that two 8-year-old samples were misclassified as 9-year-old samples. For the prediction of polyphyllin I, II, VI, and VII, the quantitative results are satisfactory, with a high value for the determination coefficient (R 2) and low values for the root-mean-square error of estimation (RMSEE), root-mean-square error of cross-validation (RMSECV), and root-mean-square error of prediction (RMSEP). In conclusion, FT-IR combined with chemometrics is a promising method to accurately discriminate samples of P. polyphylla var. yunnanensis harvested in different years and determine the content of polyphyllin I, II, VI, and VII in P. polyphylla var. yunnanensis.


Assuntos
Diosgenina/análogos & derivados , Liliaceae/química , Plantas Medicinais/química , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Espectrometria de Massas em Tandem/métodos , Diosgenina/metabolismo , Fitoterapia
20.
J Agric Food Chem ; 64(22): 4686-94, 2016 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-27192362

RESUMO

Several species of Brachiaria (Poaceae) currently cover extensive grazing areas in Brazil, providing valuable source of feed for a large cattle population. However, numerous cases of toxicity outbreaks in livestock have raised concerns on safety of using these plants, especially B. decumbens. In this study, chemometric analysis of ultrahigh-performance liquid chromatography-high-resolution quadrupole time-of-flight mass spectrometry (UHPLC-HR-QTOF-MS) data has for the first time uncovered qualitative and quantitative differences between metabolomes of toxic B. decumbens and nontoxic B. brizantha. The steroidal saponin protoneodioscin was established as the main biomarker for B. decumbens when compared to B. brizantha, and therefore the key explanation for their phytochemical differentiation. Quantification of protodioscin in both plants showed no significant differences; consequently, the idea that this compound is solely responsible for toxicity outbreaks must be discarded. Instead, we propose that the added occurrence of its stereoisomer, protoneodioscin, in B. decumbens, can be considered as the probable cause of these events. Interestingly, the greatest concentrations of saponins for both species were reached during winter (B. decumbens = 53.6 ± 5.1 mg·g(-1) dry weight (D.W.); B. brizantha = 25.0 ± 1.9 mg·g(-1) D.W.) and spring (B. decumbens = 49.4 ± 5.0 mg·g(-1) D.W.; B. brizantha = 27.9 ± 1.4 mg·g(-1) D.W.), although in the case of B. decumbens these values do not vary significantly among seasons.


Assuntos
Brachiaria/química , Cromatografia Líquida de Alta Pressão/métodos , Diosgenina/análogos & derivados , Espectrometria de Massas/métodos , Metabolômica/métodos , Saponinas/análise , Esteróis/análise , Ração Animal/análise , Animais , Brachiaria/classificação , Brachiaria/metabolismo , Brachiaria/toxicidade , Brasil , Bovinos , Diosgenina/análise , Diosgenina/metabolismo , Diosgenina/toxicidade , Saponinas/metabolismo , Saponinas/toxicidade , Estações do Ano , Esteróis/metabolismo , Esteróis/toxicidade
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA