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1.
Folia Biol (Praha) ; 67(3): 108-117, 2021.
Article in English | MEDLINE | ID: mdl-35151244

ABSTRACT

Osteosarcoma (OS), a severe malignant bone tumour, usually occurs in adolescents and children and has a poor prognosis. Asiatic acid (AA), an active component isolated from Centella asiatica (L.) Urb., exhibits appreciable anti-oxidant and anti-tumour activities. So far, the effects and underlying mechanisms of AA against OS have not been clarified. Here, we explored the anti-tumour effects of AA against human OS and the involved mechanism mediating its actions. To evaluate effects of AA on the cell proliferation of human OS cells, cell viability and colony formation assays were performed. Flow cytometry was used to evaluate apoptosis in OS cells exposed to AA and mitochondrial membrane potential. Western blotting and RT-PCR were applied to determine expression of the relevant proteins and their mRNA levels. Our explorations showed that AA inhibits proliferation of human OS cells in a concentration- and time-dependent manner, and induces apoptosis of OS cells by the intrinsic (mitochondrial) pathway. Importantly, we found that inhibition of the AA-induced phosphorylation of JAK2/STAT3 signalling molecules and the decrease in MCL-1 contributed to the anti-tumour efficacy of AA. Collectively, our results suggest that AA could evoke mitochondrial- induced apoptosis in human OS cells by suppression of the JAK2/STAT3 pathway and MCL-1 expression. These results strongly demonstrate that AA could be a potential anti-tumour agent for OS treatment.


Subject(s)
Apoptosis , Osteosarcoma , Adolescent , Cell Line, Tumor , Cell Proliferation , Humans , Janus Kinase 2 , Osteosarcoma/drug therapy , Pentacyclic Triterpenes/pharmacology , STAT3 Transcription Factor
2.
Nat Prod Res ; 33(12): 1756-1760, 2019 Jun.
Article in English | MEDLINE | ID: mdl-29446976

ABSTRACT

A novel water-soluble flavonoid with good anti-bacterial activities, naringenin-6″-succl-7-O-glucoside (7-SGN), was synthesised. It was biotransformed from naringenin by Bacillus amyloliquefaciens FJ18 in aqueous miscible organic media, and characterised by LC-MS and NMR analysis. The solubility of 7-SGN in water was approximately 102 times higher than that of naringenin. These results demonstrated that both the water solubility and the anti-bacterial activity of 7-SGN were significantly improved.


Subject(s)
Anti-Bacterial Agents/biosynthesis , Anti-Bacterial Agents/pharmacology , Flavanones/biosynthesis , Flavanones/pharmacology , Glucosides/biosynthesis , Glucosides/pharmacology , Anti-Bacterial Agents/chemistry , Bacillus amyloliquefaciens/metabolism , Biotransformation , Drug Evaluation, Preclinical/methods , Escherichia coli/drug effects , Flavanones/chemistry , Glucosides/chemistry , Magnetic Resonance Spectroscopy , Microbial Sensitivity Tests , Molecular Structure , Solubility , Staphylococcus aureus/drug effects
3.
Nat Prod Res ; 33(24): 3559-3562, 2019 Dec.
Article in English | MEDLINE | ID: mdl-29882431

ABSTRACT

Luteoloside (luteolin-7-O-glucoside), the biomarker of Lonicera japonica, was efficiently bio-synthetized from its cheaper precursor luteolin. The structure of luteoloside was characterized by LC-MS and NMR analyses. Compared to the significant inhibitory effect of luteolin on human hepatocyte cell line LO2 at high doses, luteoloside did not show obvious cytotoxic effects at any test dose. Moreover, luteoloside exhibited obvious promotive effects on human hepatocyte cells, suggesting a potential application in hepatoprotective therapies.


Subject(s)
Bacteria/metabolism , Flavobacteriaceae/chemistry , Flavones/isolation & purification , Glucosides/isolation & purification , Lonicera/chemistry , Luteolin/isolation & purification , Rhizosphere , Cell Line , Flavobacteriaceae/metabolism , Flavones/chemistry , Glucosides/biosynthesis , Glucosides/chemistry , Glucosides/pharmacology , Humans , Lonicera/microbiology , Luteolin/biosynthesis , Luteolin/chemistry , Luteolin/pharmacology , Molecular Structure , Protective Agents
4.
Sci Rep ; 8(1): 2419, 2018 02 05.
Article in English | MEDLINE | ID: mdl-29402995

ABSTRACT

In this study, a high-efficiency single-pulsed femtosecond laser assisted with chemical wet etching method has been proposed to obtain large-area concave microlens array (MLA). The quasi-periodic MLA consisting of about two million microlenses with tunable diameter and sag height by adjusting laser scanning speed and etching time is uniformly manufactured on fused silica and sapphire within 30 minutes. Moreover, the fabricated MLA behaves excellent optical focusing and imaging performance, which could be used to sense the change of the liquid refractive index (RI). In addition, it is demonstrated that small period and high RI of MLA could acquire high sensitivity and broad dynamic measurement range, respectively. Furthermore, the theoretical diffraction efficiency is calculated by the finite domain time difference (FDTD) method, which is in good agreement with the experimental results.

5.
Sci Rep ; 6: 36557, 2016 11 07.
Article in English | MEDLINE | ID: mdl-27819287

ABSTRACT

Reported here is the bio-inspired and robust function of underwater superoleophobic, anti-oil metallic surfaces with ultra-broadband enhanced optical absorption obtained through femtosecond laser micromachining. Three distinct surface structures are fabricated using a wide variety of processing parameters. Underwater superoleophobic and anti-oil surfaces containing coral-like microstructures with nanoparticles and mount-like microstructures are achieved. These properties of the as-prepared surfaces exhibit good chemical stability when exposed to various types of oils and when immersed in water with a wide range of pH values. Moreover, coral-like microstructures with nanoparticle surfaces show strongly enhanced optical absorption over a broadband wavelength range from 0.2-25 µm. The potential mechanism for the excellent performance of the coral-like microstructures with a nanoparticle surface is also discussed. This multifunctional surface has potential applications in military submarines, amphibious military aircraft and tanks, and underwater anti-oil optical counter-reconnaissance devices.


Subject(s)
Oils/chemistry , Water/chemistry , Animals , Fishes , Hydrophobic and Hydrophilic Interactions , Lasers , Lizards , Nanoparticles/chemistry , Physical Phenomena , Surface Properties
6.
Sci Rep ; 5: 18294, 2015 Dec 16.
Article in English | MEDLINE | ID: mdl-26670008

ABSTRACT

In order to develop jetting technologies of glue in LED and microelectronics packaging, giant-magnetostrictive-material (GMM) is firstly applied to increase jetting response, and a new magnifying device including a lever and a flexible hinge is designed to improve jetting characteristics. Physical models of the jetting system are derived from the magnifying structure and working principle, which involves circuit model, electro-magneto-displacement model, dynamic model and fluid-solid coupling model. The system model is established by combining mathematical models with Matlab-Simulink. The effectiveness of the GMM-based dispenser is confirmed by simulation and experiments. The jetting frequency significantly increases to 250 Hz, and dynamic behaviors jetting needle are evaluated that the velocity and displacement of the jetting needle reaches to 320 mm•s-1 and 0.11 mm respectively. With the increasing of the filling pressure or the amplitude of the current, the dot size will become larger. The dot size and working frequency can be easily adjusted.

7.
Curr Med Chem ; 19(18): 2924-56, 2012.
Article in English | MEDLINE | ID: mdl-22519396

ABSTRACT

Rheumatoid arthritis (RA) is a chronic, inflammatory disease that afflicts 1-2% of the world population, characterized by an immune mediated inflammatory synovitis that leads to joint destruction, functional impairment, and reduced quality of life. The treatment goals of RA should be longterm substantial relief of pain, arrested joint inflammation and damage, and improved function. Current treatment can be divided into four classes, namely general analgesics and non-steroidal anti-inflammatory drugs (NSAIDs), glucocorticoids, disease modifying anti-rheumatic drugs (DMARDs) and biological agents (tumor-necrosis factor modifiers). However, gastrointestinal (GI) side effects of NSAIDs cannot be neglected, direct joint injections of glucocorticoids cannot be injected more than once every 3 months, synthetic DMARDs is far from optimal and only minority of patients achieved longterm remission, the biologics are very expensive to manufacture, need to be injected, and can cause allergic reactions. An alternative and good approach to the treatment of this disease is to lower the levels of tumour necrosis factor-α (TNF-α) in RA, which can be achieved by selectively inhibiting the tumour necrosis factor-α converting enzyme (TACE) that generate these cytokines using cheaper small molecules. This review focuses on the current status of selective small molecule inhibitors of TACE, with respect to lead compound search, inhibitors design approach, structure-activity relationship (SAR) and pharmacological studies in animals and humans. Through these methods, new hope is emerging for the treatment of RA through selective inhibition of TACE.


Subject(s)
ADAM Proteins/antagonists & inhibitors , Antirheumatic Agents/chemistry , Protease Inhibitors/chemistry , ADAM17 Protein , Animals , Antirheumatic Agents/pharmacology , Antirheumatic Agents/therapeutic use , Arthritis, Rheumatoid/drug therapy , Drug Design , Humans , Protease Inhibitors/pharmacology , Protease Inhibitors/therapeutic use
8.
Genet Mol Res ; 11(1): 494-502, 2012 Mar 06.
Article in English | MEDLINE | ID: mdl-22535385

ABSTRACT

Angelica sinensis is a highly valued medicinal herb, known as female ginseng that is widely cultivated in China. Although A. sinensis is in great demand due to its multiple medicinal and food applications, its early bolting rate (almost 40%) seriously affects crop quality. To better understand its flowering mechanism, cDNA-amplified RFLP analysis was employed to look for gene expression differences between flower bud and shoot apical meristem tissues. Sixty-four primer sets were used, with each primer set amplified to 60 transcript-derived fragments. Some transcript-derived fragments were expressed only in the flower bud. After cloning, sequencing and a homology search, 46 distinct sequences were obtained; 26 of these were found to have homologous sequences in databases. These included trans-caffeoyl-CoA 3-O-methyltransferase, 1-deoxy-d-xylulose 5-phosphate reductoisomerase, 15-cis-zeta-carotene isomerase, isoamylase, and calmodulin-binding protein. These genes are closely related to pollen germination and pollen tube growth, terpenoid backbone biosynthesis, and other metabolic pathways. Confirmation of differential expression of 10 sequences was obtained by semi-quantitative RT-PCR, showing higher expression levels in flower buds.


Subject(s)
Angelica sinensis/genetics , Gene Expression Regulation, Plant , Amplified Fragment Length Polymorphism Analysis , DNA, Complementary/chemistry , Gene Expression Profiling , Molecular Sequence Annotation
9.
Phytomedicine ; 19(3-4): 239-44, 2012 Feb 15.
Article in English | MEDLINE | ID: mdl-21982434

ABSTRACT

Chinese jujube (also known as Chinese date) is the fruit of Ziziphus jujuba Mill. (Rhamnaceae). As a famous folk medicine, it is used as antidote in traditional Chinese formula, Shi Zao Decoction, to relieve the drastic inflammatory irritant nature of Euphorbia species. The irritant activities may cause serious adverse effects in clinical practices. This study aimed to investigate the active components of Z. jujuba through the inhibitory effects on the inflammatory cells activated by Euphorbia kansui and prostratin, a phorbol ester isolated from Euphorbia fischeriana. Peritoneal macrophage of rat and splenic lymphocyte (splenocyte) of mouse were selected to evaluate these actions in vitro. Nitric oxide (NO) release of macrophage and the proliferation of splenocyte were examined through Griess method and MTT assay. TNF-α, as an important pro-inflammatory cytokines, was detected with enzyme-linked immunosorbent assay (ELISA) method. Six fractions extracted from Z. jujuba were evaluated and fraction F (triterpene acids fraction) was demonstrated to be the most active part, and then, 21 compounds isolated from Z. jujuba were tested at the concentrations range from 1 µg/ml to 100 µg/ml. The results show that 7 compounds of them are likely to be active compounds concerning to their pronounced inhibitory action on the activated inflammatory cells. These effects might be helpful to attenuate the irritant action of Euphorbiaceae plants and protect the gastrointestinal tissue from potent inflammatory injury, which should be beneficial to some diseases, like inflammatory bowel disease.


Subject(s)
Anti-Inflammatory Agents/isolation & purification , Euphorbia/adverse effects , Fruit/chemistry , Inflammation/drug therapy , Plant Extracts/pharmacology , Ziziphus/chemistry , Animals , Anti-Inflammatory Agents/chemistry , Anti-Inflammatory Agents/pharmacology , Cell Proliferation , Chemical Fractionation , Enzyme-Linked Immunosorbent Assay , Euphorbia/immunology , Inflammation/pathology , Irritants/chemistry , Irritants/immunology , Irritants/pharmacology , Lymphocytes/drug effects , Lymphocytes/immunology , Lymphocytes/metabolism , Macrophage Activation , Macrophages, Peritoneal/drug effects , Macrophages, Peritoneal/immunology , Macrophages, Peritoneal/metabolism , Male , Mice , Mice, Inbred ICR , Nitric Oxide/metabolism , Phorbol Esters/adverse effects , Plant Extracts/chemistry , Rats , Rats, Sprague-Dawley , Tumor Necrosis Factor-alpha/immunology , Tumor Necrosis Factor-alpha/metabolism
10.
Curr Med Chem ; 18(7): 977-1001, 2011.
Article in English | MEDLINE | ID: mdl-21254976

ABSTRACT

Osteoarthritis (OA) is the leading cause of joint pain and disability in middle-aged and elderly patients, and is characterized by progressive loss of articular cartilage that eventually leads to a complex process involving degradation of various components of the cartilage matrix, chief among them are the cartilage-specific type II collagen (CII) and aggrecan. While the loss of aggrecan is thought to be an early and reversible process, degradation of CII is considered to be irreversible and a key step in the loss of structural and functional integrity of cartilage. Among the various matrix metalloproteinases (MMPs), MMP-13 is specifically expressed in the cartilage of human OA patients and is not present in normal adult cartilage. It is the major collagenase in OA cartilage and has the highest activity against CII. However, the clinical utility of broad-spectrum MMP inhibitors developed for treatment of OA has been restricted by dose- and duration-dependent musculoskeletal side effects in humans. Consequently, selectively inhibiting the MMP-13 would seem to be an attractive therapeutic objective. This review mainly focuses on selective MMP-13 inhibitors development in terms of OA since the late 90s, in terms of synthetic compounds of low molecular mass incorporating specific zinc-binding groups, non-zinc-binding groups. In addition, dual inhibitors of MMP-13 and aggrecanase are also reviewed. Special emphasis is placed on logistic concerns for lead compound search as well as the structure-activity relationship (SAR) in this field. Through these methods, new hope is emerging for the treatment of OA through selective inhibition of MMP-13.


Subject(s)
Matrix Metalloproteinase Inhibitors , Osteoarthritis/drug therapy , Osteoarthritis/enzymology , Protease Inhibitors/pharmacology , Cartilage/enzymology , Humans , Matrix Metalloproteinase 13/metabolism , Protease Inhibitors/chemical synthesis , Protease Inhibitors/chemistry , Structure-Activity Relationship
11.
Phytomedicine ; 15(12): 1046-52, 2008 Dec.
Article in English | MEDLINE | ID: mdl-18707853

ABSTRACT

Danggui-Shaoyao-San, a famous traditional Chinese prescription, has been widely used in China for treating various gynecological inflammatory diseases including dysmenorrhea, but it is still poorly understood how it works on those inflammatory disorders. Prostaglandin F(2alpha) (PGF(2alpha)), one important mediators of inflammation, plays crucial roles in the pathological mechanism responsible for dysmenorrhea. Here, we demonstrate that Danggui-Shaoyao-San significantly suppresses oxytocin-evoked PGF(2alpha) production of rat endometrial epithelial cells in a concentration-dependent manner. Furthermore, Danggui-Shaoyao-San-mediated down-regulation of cyclooxygenases-2 message RNA transcription, protein expression and enzyme activity in endometrial epithelial cells may be involved in the inhibitory effect on PGF(2alpha) production. Our study provides a possible mechanism for the bioactivity of Danggui-Shaoyao-San for treating dysmenorrhea and other gynecological disorders.


Subject(s)
Cyclooxygenase 2 Inhibitors/pharmacology , Cyclooxygenase 2/metabolism , Dinoprost/metabolism , Drugs, Chinese Herbal/pharmacology , Endometrium/drug effects , Animals , Cells, Cultured , Endometrium/metabolism , Epithelial Cells/drug effects , Epithelial Cells/metabolism , Female , Rats , Rats, Sprague-Dawley
12.
J Asian Nat Prod Res ; 9(3-5): 339-45, 2007.
Article in English | MEDLINE | ID: mdl-17613619

ABSTRACT

Three new germacrane sesquiterpenes, eupalinolides C-E (1-3), along with three known germacrane sesquiterpenes, eupalinolide A (4), eupalinolide B (5), and 3beta-acetoxy-8beta-(4'-hydroxytigloyloxy)-14-hydroxycostunolide (6), were isolated from Eupatorium lindleyanum. They were tested for cytotoxicity against A-549, BGC-823, SMMC-7721, and HL-60 tumour cell lines. The results showed that these compounds demonstrated potent cytotoxicity. The structures of the compounds were elucidated by means of (1)H and (13)C NMR spectroscopic analysis, including 2D NMR experiments.


Subject(s)
Antineoplastic Agents, Phytogenic/isolation & purification , Eupatorium/chemistry , Lactones/isolation & purification , Sesquiterpenes, Germacrane/isolation & purification , Antineoplastic Agents, Phytogenic/chemistry , Antineoplastic Agents, Phytogenic/pharmacology , Cell Line, Tumor , Humans , Lactones/chemistry , Lactones/pharmacology , Magnetic Resonance Spectroscopy , Sesquiterpenes, Germacrane/chemistry , Sesquiterpenes, Germacrane/pharmacology
13.
J Agric Food Chem ; 50(17): 4861-6, 2002 Aug 14.
Article in English | MEDLINE | ID: mdl-12166972

ABSTRACT

Radix Astragali (root of Astragalus; Huangqi) is a popular traditional Chinese medicine, and Astragalus membranaceus and A. membranaceus var. mongolicus are two commonly used species; however, there are many Astragalus species that could act as adulterants of Radix Astragali. To find the chemical composition of Radix Astragali, the main constituents including flavonoids, saponins, polysaccharides, amino acids, and trace elements were determined in two Radices Astragali, A. membranaceus and A. membranaceus var. mongolicus, and its eight adulterants, Astragalus propinquus, Astragalus lepsensis, Astragalus aksuensis, Astragalus hoantchy, Astragalus hoantchy subsp. dshimensis, Astragalus lehmannianus, Astragalus sieversianus, and Astragalus austrosibiricus. The results showed that the amounts of main constituents such as isoflavonoids and astragalosides varied in different species. In distinction, A. membranaceus and A. membranaceus var. mongolicus contained a higher amount of astragaloside I and IV. In addition, the main constituents of A. membranaceus var.mongholicus changed according to seasonal variation and age of the plant. The chemical composition of different species of Astragalus would provide useful information for the quality control of Radix Astragali.


Subject(s)
Astragalus Plant/chemistry , Drugs, Chinese Herbal/analysis , Plant Roots/chemistry , Amino Acids/analysis , Astragalus propinquus , China , Chromatography, High Pressure Liquid , Flavonoids/analysis , Polysaccharides/analysis , Quality Control , Saponins/analysis , Seasons , Species Specificity , Trace Elements/analysis
14.
Zhongguo Zhong Yao Za Zhi ; 26(5): 296-9, 2001 May.
Article in Chinese | MEDLINE | ID: mdl-12528516

ABSTRACT

OBJECTIVE: To study the genetic diversity of Pinellia ternata. on the chemical composition. METHOD: Fifteen populations of Pinellia ternata. originated mostly from middle and lower reaches of Yangtze River valley were collected and cultivated in Weigang Experimental Farm of Nanjing Agricultural University with same cultural conditions, and contents in three types of index chemicals extracted from tubers of the populations have been compared continuously. RESULT AND CONCLUSION: The difference in contents of beta-sitosterol and Val and Arg extracted from tubers of the populations has been observed, and those contents are also different with harvesting time. But the mean contents of each of the three types of chemicals in autumn are all higher than those in summer respectively.


Subject(s)
Arginine/analysis , Pinellia/chemistry , Sitosterols/analysis , Valine/analysis , Genetic Variation , Pinellia/genetics , Pinellia/growth & development , Seasons
15.
Phytochemistry ; 54(4): 363-8, 2000 Jun.
Article in English | MEDLINE | ID: mdl-10897476

ABSTRACT

About 300 species and varieties of Astragalus are identified in China, making the identification of the origin of a particular Astragalus species on the consumer market difficult. A molecular genetic approach was developed to identify various species of Astragalus. Although the 5S-rRNA coding sequence is conserved in higher eukaryotes, the spacer domain of the 5S-rRNA gene has great diversity among different species. The 5S-rRNA spacer domain was amplified by polymerase chain reaction (PCR) from the isolated genomic DNA, and the PCR products (approximately 300 bp) covering the 5S-rRNA spacer domain were sequenced. The nucleotide sequences of Astragalus membranaceus, A. membranaceus var. mongholicus, A. lehmannianus, A. hoantchy, and of one closely related species Hedysarum polybotrys (Hongqi), were determined. Diversity in DNA sequence and restriction enzyme mapping among various species was found in their 5S-rRNA spacer domains. This is the first report on the detection of 5S-rRNA spacer region sequence of Astragalus, and the results could be used for genetic identification of Huangqi.


Subject(s)
Plants, Medicinal/classification , RNA, Ribosomal, 5S/genetics , Astragalus propinquus , Base Sequence , Medicine, Chinese Traditional , Molecular Sequence Data , Plants, Medicinal/genetics , Polymerase Chain Reaction , Sequence Analysis, DNA , Sequence Homology, Nucleic Acid , Species Specificity
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