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1.
Nat Prod Res ; : 1-7, 2024 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-38752874

RESUMO

Two new withanolides named physaminilides L (1) and M (2), together with four known ones (3-6) were isolated from the Physalis minima L. The structures were established by analysis of the HR ESIMS, IR and NMR spectroscopic data. The absolute configurations were determined through NOESY and ECD spectra. For compounds 1-5 assayed at 20 µM and compound 6 at 10 µM, inhibition rates of hepatic fibrosis were 22.19%, 15.29%, 37.07%, 9.27%, 12.45%, and 37.03%, respectively.

2.
J Ethnopharmacol ; 325: 117830, 2024 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-38301983

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Physalis angulata L., a traditional Chinese medicine called "Kuzhi" in China, was used traditionally to treat liver diseases (eg. icterus, hepatitis) as well as malaria, asthma, and rheumatism. AIM OF THE STUDY: Our study aimed to investigate the withanolides with anti-hepatic fibrosis effect from P. angulate. MATERIALS AND METHODS: Withanolides were obtained from the EtOH extract of P. angulate by bioassay-molecular networking analysis-guided isolation using column chromatography and normal/reversed-phase semipreparative HPLC. The structures of new withanolides were elucidated by combinations of spectroscopic techniques with NMR and ECD calculations. MTT cell viability assay, AO/EB staining method, cell wound healing assay, ELISA and Western blot experiments were employed to evaluate the anti-hepatic fibrosis activity and to uncover related mechanism. Molecular docking analysis and cellular thermal shift assay were used to evaluate and verify the interaction between the active withanolides and their potential targets. RESULTS: Eight unreported withanolides, withagulides A-H (1-8), along with twenty-eight known ones were obtained from P. angulate. Withanolides 6, 9, 10, 24, 27, and 29-32 showed marked anti-hepatic fibrosis effect with COL1A1 expression inhibition above 50 %. Physalin F (9), the main component in the active fraction, significantly decreased the TGF ß1-stimulated expressions of collagen I and α-SMA in LX-2 cells. Mechanism study revealed that physalin F exerted its anti-hepatic fibrosis effect via the PI3K/AKT/mTOR signaling pathway. CONCLUSION: This study suggested that withanolides were an important class of natural products with marked anti-hepatic fibrosis effect. The main withanolide physalin F might be a promising candidate for hepatic fibrosis treatment. The work provided experimental foundation for the use of P. angulate to treat hepatic fibrosis.


Assuntos
Physalis , Vitanolídeos , Vitanolídeos/farmacologia , Vitanolídeos/uso terapêutico , Vitanolídeos/química , Physalis/química , Simulação de Acoplamento Molecular , Fosfatidilinositol 3-Quinases , Cirrose Hepática/induzido quimicamente , Cirrose Hepática/tratamento farmacológico , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico , Extratos Vegetais/química
3.
Molecules ; 29(2)2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38257331

RESUMO

Liver fibrosis is the initial pathological process of many chronic liver diseases. Targeting hepatic stellate cell (HSC) activation is an available strategy for the therapy of liver fibrosis. We aimed to explore the anti-liver fibrosis activity and potential mechanism of phomopsterone B (PB) in human HSCs. The results showed that PB effectively attenuated the proliferation of TGF-ß1-stimulated LX-2 cells in a concentration-dependent manner at doses of 1, 2, and 4 µM. Quantitative real-time PCR and Western blot assays displayed that PB significantly reduced the expression levels of α-SMA and collagen I/III. AO/EB and Hoechst33342 staining and flow cytometry assays exhibited that PB promoted the cells' apoptosis. Meanwhile, PB diminished the number of autophagic vesicles and vacuolated structures, and the LC3B fluorescent spots indicated that PB could effectively inhibit the accretion of autophagosomes in LX-2 cells. Moreover, rapamycin and MHY1485 were utilized to further investigate the effect of mTOR in autophagy and apoptosis. The results demonstrated that PB regulated autophagy and apoptosis via the mTOR-dependent pathway in LX-2 cells. In summary, this is the first evidence that PB effectively alleviates liver fibrosis in TGF-ß1-stimulated LX-2 cells, and PB may be a promising candidate for the prevention of liver fibrosis.


Assuntos
Autofagia , Fator de Crescimento Transformador beta1 , Humanos , Cirrose Hepática/tratamento farmacológico , Autofagossomos , Apoptose
4.
Ying Yong Sheng Tai Xue Bao ; 33(4): 1045-1054, 2022 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-35543058

RESUMO

Timing of leaf senescence is important to ensure maize yield. In this study, we investigated the dynamics of carbon and nitrogen balance during leaf senescence in two maize inbred lines PH6WC and PH4CV under normal (4 mmol·L-1, CK) and low nitrogen (0.04 mmol·L-1, LN) treatments. Leaf phenotype, photosynthetic characteristics, nitrogen and sugar contents, and carbon to nitrogen ratio of the second and third leaves were analyzed after 2, 4, 6 and 8 days of cultivation. Results showed that leaf size, biomass, relative chlorophyll content, net photosynthetic rate, soluble sugar content, and starch content of the second and third leaves were decreased, while nitrogen production capacity was increased under low nitrogen treatment compared to the control, with the changes of the second leaf being earlier than that of the third leaf. For all the leaf traits, the variation scales of PH6WC were larger than that of PH4CV under low nitrogen stress, and only the C/N ratio in the seedling leaves was significantly increased. In addition, leaf senescence of PH4CV was slower than PH6WC due to its stronger ability in maintaining carbon and nitrogen balance. In conclusion, low nitrogen could induce leaf senescence of maize seedlings. High C/N ratio could promote leaf senescence. There are significant differences in carbon and nitrogen balance ability of seedling leaves between two maize genotypes under low nitrogen stress.


Assuntos
Nitrogênio , Zea mays , Carbono , Nitrogênio/farmacologia , Fotossíntese , Folhas de Planta , Senescência Vegetal , Plântula , Açúcares
5.
Front Plant Sci ; 11: 558, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32499802

RESUMO

Polyploidy plays an important role in crop improvement. Polyploid plants, particularly those produced through unreduced gametes (2n gametes), show increased organ size, improved buffering capacity for deleterious mutations, and enhanced heterozygosity and heterosis. Induced polyploidy has been widely used for improving floriculture crops, however, there are few reported sexual polyploid plants in the floriculture industry. This study evaluated nine cultivars of Cymbidium Swartz and discovered that 2n male gametes occurred in this important orchid. Depending on cultivars, 2n male gamete formation frequencies varied from 0.15 to 4.03%. Interspecific hybrids generally produced more 2n male gametes than traditional cultivars. To generate sexual polyploid plants, seven pairs of crosses were made, which produced five triploid and two tetraploid hybrids. Two triploid hybrids were evaluated for in vitro regeneration and growth characteristics. Compared to the diploid parents, the triploids were more easily regenerated through rhizomes or protocorms, and regenerated plants had improved survival rates after transplanting to the greenhouse. Furthermore, the sexual polyploid plants had more compact growth style, produced fragrant flowers, and demonstrated heterosis in plant growth. Through this study, a reliable protocol for selection of appropriate parents for 2n gamete production, ploidy level evaluation, in vitro culture of polyploid progenies, and development of new polyploid cultivars was established. Our study with Cymbidium suggests that the use of 2n gametes is a viable approach for improving floriculture crops.

6.
Environ Sci Pollut Res Int ; 21(17): 10349-60, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24817679

RESUMO

In order to evaluate the potential adverse health effects of odor emissions from wastewater pump stations (WWPSs) to human, a health risk assessment was performed to study the odors emitted from an urban WWPS in a residential area, Tianjin (in North China). First, 15 types of volatile organic compounds in the WWPS were collected and analyzed using gas chromatography-mass spectrometry. Next, Monte Carlo probabilistic modeling was applied to evaluate the potential health effects of four odors (chlorobenzene, dichloromethane, hydrogen sulfide, and carbon disulfide), which had higher concentrations. The results revealed that the 95th percentile of the total non-carcinogenic risk was approximately 1.73, which poses a threat to human health. In addition, hydrogen sulfide had the highest non-carcinogenic risk value of the four; the hazard quotient of hydrogen sulfide was estimated to be 1.60 at the 95th percentile, higher than the upper confidence limit (1.0). The 95th percentile of the carcinogenic risk was approximately 5.47E-08, much lower than the maximum acceptable level (1.0E-06). Finally, the influence of the input variables on the output was evaluated using sensitivity analysis, and contaminant concentration, reference concentration, and inhalation unit risk were the most influential variables.


Assuntos
Poluentes Atmosféricos/análise , Odorantes/análise , Águas Residuárias/química , China , Saúde , Humanos , Medição de Risco/métodos
7.
J Control Release ; 138(2): 103-12, 2009 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-19433120

RESUMO

Targeted drug delivery system of traditional Chinese medicine (TCM) refers to those using different carriers to make the effective parts or monomer extracted from TCM or natural medicine into agents which can directly concentrate on the target site. This system is an ideal delivery approach and has became a hot spot in the field of TCM pharmaceutical research since it can improve the pharmacological effects and reduce the adverse reactions. This paper reviews literatures on TCM targeted agents which were published in the past 10 years. In accordance with the different carriers, four types of agents, liposome, nanoparticle, microsphere, and emulsion are analyzed. Liposomes were studied most profoundly and a variety of new types of liposomes was developed on the basis of the traditional liposomes. Using natural or synthetic polymer materials to carry drugs, nanoparticles and microspheres can promote the drug through the blood-brain barrier and enhance its bioavailability. Emulsion has lymphatic affinity and the drug is coated in the internal phase, which can protect the drugs from hydrolysis. All these delivery agents are proved to be effective ways to improve the clinical efficacy of drugs, and each is discussed in detail with examples. At present, TCM targeted agents are still in the exploratory stage and many problems need to be solved. Especially, it is a huge challenge to research the targeted delivery systems for the effective parts of Chinese medicines and compound prescriptions, and the paper gives a particular discussion on this point. In the future, more attention should be paid to the research on the particle agents of TCM effective parts, and the development of new carrier materials in order to enhance the overall quality of TCM targeted agents.


Assuntos
Sistemas de Liberação de Medicamentos/métodos , Medicina Tradicional Chinesa , Preparações Farmacêuticas/administração & dosagem , Emulsões , Lipossomos , Microesferas , Nanopartículas , Propriedades de Superfície
8.
J Zhejiang Univ Sci B ; 9(9): 675-83, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18763299

RESUMO

In recent years, China has become an increasingly important and the largest chestnut producer in the world. This study aimed to evaluate the nutritional value and microbiological quality of the roasted freeze-dried Chinese chestnut (Castanea mollissima) (RFDC) coated with dark chocolate (DCC) and milk chocolate (MCC) for industrial use and commercial consumption. Chocolate coating significantly improved the nutritional value of chestnut. RFDC had high levels of starch (66.23%) and fibers (3.85%) while DCC and MCC contained significantly high amounts of sucrose, protein, fat and minerals. Furthermore, the protein content doubled in MCC rather than in DCC. This could be attributed to the different formulations in the two products. Milk powder and whey protein constituted the source of protein in MCC while cocoa powder added to MCC formulation constituted an additional source of minerals. The amino acid profile showed differences in amino acid composition related to the sample's protein content, indicating their good nutritional quality. The moisture contents in all RFDC, DCC and MCC were suitable for industrial processing. These results provide information about the additional nutrients of chocolate-coated chestnut and confirm that the product is an interesting nutritional food. The combination of freeze-drying and chocolate-coating generally results in greater reductions on microbiological loads, extending shelf life of harvested chestnut for commercial application. This is an alternative strategy to add value to chestnut, minimizing the significant losses in harvested fruits and providing a wider range of choices of new products to the consumer disposal.


Assuntos
Cacau/química , Cacau/microbiologia , Fagaceae/química , Fagaceae/microbiologia , Análise de Alimentos , Frutas/química , Frutas/microbiologia , China , Manipulação de Alimentos/métodos , Microbiologia de Alimentos , Embalagem de Alimentos/métodos , Valor Nutritivo
9.
Colloids Surf B Biointerfaces ; 63(1): 41-7, 2008 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-18155888

RESUMO

Gelatin-gum arabic spherical multinuclear microcapsules (SMMs) encapsulating peppermint oil were prepared by complex coacervation. Transglutaminase (TG) was used to harden the SMMs by complex coacervation instead of traditional reagents such as formaldehyde or glutaraldehyde. The effect of various cross-linking parameters on the hardening effectiveness of SMMs containing peppermint oil was investigated. The optimum parameters were as follows: hardening for 6h at 15 degrees C and pH 6.0 with a TG concentration of 15 U/g gelatin. Compared with formaldehyde, TG exhibits similar microcapsule hardening effectiveness.


Assuntos
Cápsulas , Transglutaminases/química , Reagentes de Ligações Cruzadas , Excipientes , Formaldeído/química , Gelatina , Goma Arábica , Concentração de Íons de Hidrogênio , Mentha piperita , Tamanho da Partícula , Óleos de Plantas/administração & dosagem , Óleos de Plantas/química , Temperatura , Triglicerídeos/química , Água
10.
Food Chem ; 108(2): 439-45, 2008 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-26059120

RESUMO

Type II collagen was purified from sternal cartilage of the chick using a combination of pepsin digestion, NaCl precipitation and DEAE-sepharose CL 6B ion exchange chromatography. Pepsin-solubilized type II collagen of higher stability can be obtained with the extraction time of 32h, 0.5% pepsin concentration at 20°C. The purified preparation showed a single peak on RP-HPLC and a single band (α-chain) and its dimers (ß-chains) on SDS-PAGE with a subunit Mr of 110kDa. The amino acid composition of the type II collagen derived from chick cartilage was closer to that of reference Sigma-Aldrich type II collagen which contains more imino acid. Analysis by differential scanning calorimetry (DSC) and Fourier transform infrared spectroscopy (FTIR) revealed that type II collagen from chick sternal cartilage retains more intermolecular crosslinks during the purification process. Collagen purified from chick sternal cartilage was typical type II collagen and may find applications in functional foods.

11.
J Mater Sci Mater Med ; 19(2): 567-75, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18058201

RESUMO

Three-dimensional biodegradable porous type II collagen scaffolds are interesting materials for cartilage tissue engineering. This study reports the preparation of porous type II collagen-chondroitin sulfate (CS) scaffold using variable concentrations of 1-ethyl-3(3-dimethyl aminopropyl) carbodiimide (EDC) and N-hydroxysuccinimide (NHS). The physico-chemical properties and ultrastructural morphology of the collagen scaffolds were determined. Then, isolated chondrocytes were cultured in porous type II collagen scaffolds either in the presence and/or absence of covalently attached CS up to 14 days. Cell proliferation, the total amount of proteoglycans and type II collagen retained in the scaffold and chondrocytes morphology were evaluated. The results suggest that EDC-crosslinking improves the mechanical stability of collagen-CS scaffolds with increasing EDC concentration. Cell proliferation and the total amount of proteoglycans and type II collagen retained in the scaffolds were higher in type II collagen-CS scaffolds. Histological analysis showed the formation of a denser cartilaginous layer at the scaffold periphery. Scanning electron microscopy (SEM) revealed chondrocytes distributed the porous surface of both scaffolds maintained their spherical morphology. The results of the present study also indicate that type II collagen-CS scaffolds have potential for use in tissue engineering.


Assuntos
Sulfatos de Condroitina/química , Colágeno Tipo II/química , Etildimetilaminopropil Carbodi-Imida , Animais , Materiais Biocompatíveis/química , Galinhas , Condrócitos/fisiologia , Reagentes de Ligações Cruzadas/química , DNA/química , Glicosaminoglicanos/química , Microscopia Eletrônica de Varredura , Coelhos , Fatores de Tempo , Alicerces Teciduais
12.
J Comp Physiol B ; 177(6): 655-66, 2007 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-17562054

RESUMO

Two trypsin isoforms (GT-A and GT-B) from the grass carp (Ctenopharyngodon idellus) intestine were isolated and purified. SDS-PAGE electrophoresis showed that GT-A and GT-B had relative molecular masses of 30,740 and 26,400, respectively. Enzyme activity was inhibited by three organic trypsin inhibitors but not by EDTA. They had optimal pH of 8.0 and 8.5, and optimal temperatures of 38.5 and 44.0 degrees C, respectively, when hydrolyzing N-benzoyl-L: -arginine ethyl ester.HCl (BAEE). They lost 95.8 and 93.7% of their activities, respectively, after heating for 20 min at 65 degrees C. Their thermal denaturation temperatures, respectively, were 66.3 and 67.3 degrees C. GT-A has a K(m) value of 21.2 microM and a V(max) of 2.0 x 10(3) min(-1), and GT-B has a K(m) value of 31.7 microM and a V(max) of 3.3 x 10(3) min(-1). Their physiological efficiencies were 94.3 and 105.3 microM(-1) min(-1), respectively. The Arrhenius activation energies of GT-A and GT-B were 4.16 and 4.38 kcal/mol, respectively. The activities of GT-A and GT-B were not activated by Ca(2+), but their thermostability was improved in the presence of Ca(2+). Enzyme activity was reduced in presence of Zn(2+), Cu(2+), Hg(2+) and Al(3+). Thermal stabilities of GT-A and GT-B were intermediate between Arctic and tropical fish species, and consistent with the wide range of water temperatures to which grass carp are exposed in most provinces of China.


Assuntos
Carpas/metabolismo , Intestinos/enzimologia , Isoenzimas/isolamento & purificação , Isoenzimas/metabolismo , Tripsina/metabolismo , Alumínio/farmacologia , Animais , Cobre/farmacologia , Relação Dose-Resposta a Droga , Eletroforese em Gel de Poliacrilamida , Ativação Enzimática , Inibidores Enzimáticos/farmacologia , Estabilidade Enzimática , Temperatura Alta , Concentração de Íons de Hidrogênio , Íons/farmacologia , Isoenzimas/química , Cinética , Mercúrio/farmacologia , Peso Molecular , Fluoreto de Fenilmetilsulfonil/farmacologia , Desnaturação Proteica , Tosilina Clorometil Cetona/farmacologia , Tripsina/química , Tripsina/isolamento & purificação , Inibidor da Tripsina de Soja de Kunitz/farmacologia , Zinco/farmacologia
13.
J Agric Food Chem ; 55(10): 3896-904, 2007 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-17432869

RESUMO

An initial 5% (w/v), followed thereafter with replacement aliquots of 3% (w/v), whey protein isolate (WPI) (ca. 86.98% Kjeldahl N x 6.38), was hydrolyzed using Protease N Amano G (IUB 3.4.24.28, Bacillus subtilis) in an enzymatic membrane reactor (EMR) fitted with either a 10 or 3 kDa nominal molecular weight cutoff (NMWCO) tangential flow filter (TFF) membrane. The hydrolysates were desalted by adsorption onto a styrene-based macroporous adsorption resin (MAR) and washed with deionized water to remove the alkali, and the peptides were desorbed with 25, 50, and 95% (v/v) ethyl alcohol. The desalted hydrolysates were analyzed for antibody binding, free radical scavenging, and molecular mass analysis as well as total and free amino acids (FAA). For the first time a quantity called IC50, the concentration of peptides causing 50% inhibition of the available antibody, is introduced to quantify inhibition enzyme-linked immunosorbent assay (ELISA) properties. Principal component analysis (PCA) was used for data reduction. The hydrolysate molecular mass provided the most prominent influence (PC1 = 57.35%), followed by inhibition ELISA (PC2 = 18.90%) and the antioxidant properties (PC3 = 10.43%). Ash was significantly reduced in the desalted fractions; the protein adsorption recoveries were high, whereas desorption with alcohol was prominently influenced by the hydrophobic/ hydrophilic amino acid balance. After hydrolysis, some hydrolysates showed increased ELISA reactivity compared with the native WPI.


Assuntos
Antioxidantes/farmacologia , Proteínas do Leite/química , Proteínas do Leite/imunologia , Hidrolisados de Proteína/química , Análise de Variância , Ensaio de Imunoadsorção Enzimática , Hidrólise , Proteínas do Leite/farmacologia , Proteínas do Soro do Leite
14.
Carbohydr Res ; 341(9): 1135-46, 2006 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-16643873

RESUMO

A fucoidan, obtained from the hot-water extract of the brown seaweed, Hizikia fusiforme, was separated into five fractions by DEAE Sepharose CL-6B and Sepharose CL-6B column chromatography. All five fractions contained predominantly fucose, mannose and galactose and also contained sulfate groups and uronic acid. The fucoidans had MWs from 25 to 950 kDa. The structure of fraction F32 was investigated by desulfation, carboxyl-group reduction, partial hydrolysis, methylation analysis and NMR spectroscopy. The results showed that the sugar composition of F32 was mainly fucose, galactose, mannose, xylose and glucuronic acid; sulfate was 21.8%, and the MW was 92.7 kDa. The core of F32 was mainly composed of alternating units of -->2)-alpha-D-Man(1--> and -->4)-beta-D-GlcA(1-->, with a minor portion of -->4)-beta-D-Gal(1--> units. The branch points were at C-3 of -->2)-Man-(1-->, C-2 of -->4)-Gal-(1--> and C-2 of -->6)-Gal-(1-->. About two-thirds of the fucose units were at the nonreducing ends, and the remainder were (1-->4)-, (1-->3)- and (1-->2)-linked. About two-thirds of xylose units were at the nonreducing ends, and the remainder were (1-->4)-linked. Most of the mannose units were (1-->2)-linked, and two-thirds of them had a branch at C-3. Galactose was mainly (1-->6)-linked. The absolute configurations of the sugar residues were alpha-D-Manp, alpha-L-Fucp, alpha-D-Xylp, beta-D-Galp and beta-D-GlcpA. Sulfate groups in F32 were at C-6 of -->2,3)-Man-(1-->, C-4 and C-6 of -->2)-Man-(1-->, C-3 of -->6)-Gal-(1-->, C-2, C-3 or C-4 of fucose, while some fucose had two sulfate groups. There were no sulfate groups in either the GlcA or xylose residues.


Assuntos
Phaeophyceae , Polissacarídeos/química , Sequência de Carboidratos , Fucose/química , Dados de Sequência Molecular
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