Antifungal drug resistance is a significant clinical problem, and antifungal agents that can evade resistance are urgently needed. In infective niches, resistant organisms often co-existed with sensitive ones, or a subpopulation of antibiotic-susceptible organisms may evolve into resistant ones during antibiotic treatment and eventually dominate the whole population. In this study, we established a co-culture assay in which an azole-resistant Candida albicans strain was mixed with a susceptible strain labeled with green fluorescent protein to mimic in vivo conditions and screen for antifungal drugs. Fluconazole was used as a positive control to verify the validity of this co-culture assay. Five natural molecules exhibited antifungal activity against both susceptible and resistant C. albicans. Two of these compounds, retigeric acid B (RAB) and riccardin D (RD), preferentially inhibited C. albicans strains in which the efflux pump MDR1 was activated. This selectivity was attributed to greater intracellular accumulation of the drugs in the resistant strains. Changes in sterol and lipid compositions were observed in the resistant strains compared to the susceptible strain, and might increase cell permeability to RAB and RD. In addition, RAB and RD interfered with the sterol pathway, further aggregating the decrease in ergosterol in the sterol synthesis pathway in the MDR1-activated strains. Our findings here provide an alternative for combating resistant pathogenic fungi.
ATP-Binding Cassette Transporters ; genetics ; metabolism ; Antifungal Agents ; chemistry ; metabolism ; pharmacology ; Azoles ; pharmacology ; Biosynthetic Pathways ; drug effects ; genetics ; Candida albicans ; chemistry ; drug effects ; metabolism ; Cell Membrane ; chemistry ; metabolism ; Coculture Techniques ; Drug Resistance, Fungal ; drug effects ; Ergosterol ; metabolism ; Fungal Proteins ; genetics ; metabolism ; Lipids ; chemistry ; Molecular Structure ; Permeability ; Phenyl Ethers ; chemistry ; metabolism ; pharmacology ; Sterols ; chemistry ; metabolism ; Stilbenes ; chemistry ; metabolism ; pharmacology ; Triterpenes ; chemistry ; metabolism ; pharmacology

Pterostilbene (3,5-dimethoxy-4'-hydroxystilbene) is a polyphenolic compound primarily found in blueberries, grapes, and a tree wood, pterocarpus marsupium. Studies demonstrate that pterostilbene inhibits a variety of cancers, such as lung, breast, stomach, colon, etc. The anti-cancer activities are related to the regulation of several hallmarks of cancer. Moreover, pterostilbene exhibits much greater bioavailability and bioactivity than resveratrol which warrants further investigation in the anti-cancer functions and mechanisms.
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Animals ; Antineoplastic Agents, Phytogenic ; chemistry ; pharmacology ; Humans ; Neoplasms ; drug therapy ; Plant Extracts ; chemistry ; pharmacology ; Stilbenes ; chemistry ; pharmacology

The present study was designed to synthesize derivatives of E-resveratrol and evaluate their cytotoxic activity in vitro. Different functional groups were conjugated with the phenolic hydroxyl group of E-resveratrol, and the double bond of E-resveratrol was reduced. The in vitro cytotoxicity of the synthetic derivatives was evaluated against three tumor cell lines (A549, LAC, and HeLa) using the MTT assay. Twenty-six E-resveratrol derivatives were synthesized and their structures were confirmed by (1)H NMR, MS, IR, and elemental analyses. Compounds 1-6, 12, 15-21, and 23-26 were reported for the first time. Among them, Compounds 1, 2, 4, 5, and 9-11, showed significant cytotoxicity against tumor cells; especially, Compound 1 showed an IC50 value of 4.38 μmol · L(-1) in the A549 cells which was 15-fold more active than E-resveratrol; Compound 9 showed an IC50 value of 1.41 μmol · L(-1) in the HeLa cell line which was 90-fold more active than E-resveratrol, and close to adriamycin. The structure-activity relationships were also investigated. Compounds 1, 2 and 9-11 may serve as potential lead compounds for the discovery of new anticancer drugs.
Adenocarcinoma ; drug therapy ; Antineoplastic Agents ; chemical synthesis ; chemistry ; pharmacology ; Cell Line, Tumor ; Female ; HeLa Cells ; Humans ; Inhibitory Concentration 50 ; Lung Neoplasms ; drug therapy ; Resveratrol ; Stilbenes ; chemical synthesis ; chemistry ; pharmacology ; Structure-Activity Relationship ; Uterine Cervical Neoplasms ; drug therapy

OBJECTIVETo study major antioxidant active compounds in Mori Ramulus.

METHODThe combination of on-line HPLC method and liquid chromatography-mass spectrometry was used to identify major antioxidant compounds and their content was determined by HPLC-DAD (detection wavelength of 320 nm).

RESULTOxyresveratrol was proved to be the major antioxidant compound in Mori Ramulus ethanolic extracts. Using the HPLC-DAD quantitative determination, Mori Ramulus oxyresveratrol had a good linear range of 14-1 260 mg x L(-1) (r = 0.999 96). The average recovery was 98.2% with RSD of 1.2%. This method is simple, rapid, accurate and sensitive. There was rich oxyresveratrol in Mori Ramulus and the content was significantly different according to the mulberry varieties.

CONCLUSIONThe on-line HPLC-MS-DPPH method is applicable for the determination of antioxidant compounds in Mori Ramulus.

Antioxidants ; analysis ; chemistry ; isolation & purification ; Chromatography, High Pressure Liquid ; methods ; Drugs, Chinese Herbal ; chemistry ; pharmacology ; toxicity ; Mass Spectrometry ; Medicine, Chinese Traditional ; Morus ; chemistry ; Plant Extracts ; analysis ; chemistry ; isolation & purification ; Plant Leaves ; chemistry ; Reproducibility of Results ; Sensitivity and Specificity ; Stilbenes ; analysis ; chemistry ; isolation & purification ; Time Factors

OBJECTIVETo investigate the effects of cis-combretastatin-A1 phosphate (cis-CA1P) on tumor cell proliferation, and its effects on the blood vessel formations.

METHODSMTT and IC50 values were used to assess the inhibitory effects of cis-CA1P on tumor cell proliferation. Chicken embryo chorioallantoic membrane and thoracic aorta annulations isolated from rats were used to investigate the effects of cis-CAIP on the blood vessel formation.

RESULTSCis-CA1P concentration-dependently inhibited the proliferations of several cancer cell lines, including human gastric carcinoma cell line MGC-803, human leukemic monocyte lymphoma cell line U937, human melanoma cell line A375, human colon cancer cell line HCT116, human breast carcinoma cell line MDA-MB-231, and human leukemia cell line K562. Cis-CAIP significantly decreased the formation of blood vessels in chicken embryo chorioallantoic membrane and in thoracic aorta annulations.

CONCLUSIONCis-CA1P inhibits cancer cell proliferation and prevents blood vessel formation.

Animals ; Aorta ; drug effects ; Cell Line, Tumor ; Cell Proliferation ; drug effects ; Chick Embryo ; Chorioallantoic Membrane ; blood supply ; drug effects ; Humans ; In Vitro Techniques ; Neovascularization, Pathologic ; prevention & control ; Phosphates ; pharmacology ; Rats ; Stilbenes ; chemistry ; pharmacology

OBJECTIVE: To synthesize 3, 5, 4' -trimethoxystilbene (TMS) by methylation of resveratrol (Res), a natural compound extracted from polygonum cuspidatum, to identify the chemical structure of TMS, to test its pharmacokinetics, and to determine the effects of TMS on the growth inhibition and apoptosis in pulmonary artery smooth muscle cells (PASMCs). METHODS: The chemical structure of TMS was analyzed by UV- and IR- absorption spectrometry, (1)H-NMR and (13)C-NMR spectroscopy and mass spectrometry. We measured the bioavailability, the characteristics of intestinal absorption, and the distribution of TMS in body and excretions of SD rats after oral administration of TMS. The acute toxicity of TMS in mice was tested. PASMCs were prepared from pulmonary artery of SD rats. The PASMCs were divided into 8 groups. Group of A (control) was cultured without TNF-α, TMS, or Res. Group of B (TNF-α) was cultured with 100 pg/mL TNF-α. Groups of C-E (low-high concentrations of TMS) were cultured with 100 pg/mL TNF-α and 5, 10, 20 μmol/L TMS, respectively. Groups of F-H (low-high concentrations of Res) were cultured with 100 pg/mL TNF-α and 50, 100, 200 μmol/L Res, respectively. The proliferation of PASMCs after treatment was determined by MTT assay. The apoptosis of PASMCs after treatment was determined by flow cytometry. RESULTS: The UV absorption map of TMS showed λmax(MeOH) at 318, 306.2, and 217.8 nm. Analysis of infrared spectrum of TMS showed IRvKBr max /cm at 2999, 2935, 2836, 1591, 1511 and 1456/cm. The (1)H-NMR map showed that the synthetic product contained three hydroxy groups, while (13)C-NMR map showed 17 carbon signals and some symmetrical structural fragments. Electospray ionization mass spectrometry of the productshowed m/z peaks corresponded to 271[M+H](+), 256[M+H-CH(3)](+) and 241[256-CH(3)](+); the implied relative molecular weight is 270 and the implied molecular formula is C17H18O3. These data confirm the product is 3,5,4' - trimethoxystilbene. The absolute bioavailability of TMS was 45.4%. TMS was well absorped in the upper small intestine; it was excreted in stool and bile and distributed into several tissues. The maximal tolerance dose (MTD) of TMS was 5.85 g/kg. MTT assay showed TMS inhibited the proliferation of PASMCs in a dose-dependent manner. The extent of growth inhibition in A-H groups were (4.07±2.12)%, (6.54±4.78)%, (9.35±4.26)%, (16.75±5.34)%, (23.74±7.07)%, (6.78±5.58) %, (8.81±5.16) %, and (17.81±6.03) %, respectively. Flow cytometry showed the extent of apoptosis in PASMCs (after being treated with TMS for 24 h) was significantly higher than that in PASMCs treated only with TNF-α. The apoptosis rates of A-H groups were (2.63±0.74)%, (3.54±0.81)%, (5.77±4.62)%, (11.68±5.35)%, (18.79±4.15)%, (4.11±3.59)%, (6.33±4.8) %, and (12.47±5.06)%, respectively. CONCLUSION We have confirmed our synthetic product as 3,5,4'-trimethoxystilbene (TMS), with the molecular formula of C17H18O3 and appropriate molecular weight and absorbption and NMR spectra. The bioavailability of TMS was to 45%. It strongly inhibits the proliferation of PASMCs in a dose-dependent manner and induces apoptosis of PASMCs.
Animals ; Anti-Inflammatory Agents ; pharmacology ; Apoptosis ; drug effects ; Cell Proliferation ; Cells, Cultured ; Male ; Myocytes, Smooth Muscle ; cytology ; drug effects ; metabolism ; Pulmonary Artery ; cytology ; drug effects ; metabolism ; Rats ; Rats, Sprague-Dawley ; Resveratrol ; Stilbenes ; chemical synthesis ; chemistry ; isolation & purification ; pharmacokinetics ; pharmacology

The interaction mechanism between rhaponticin (RT) and human serum albumin (HSA) has been studied by fluorescence spectroscopy and absorbance spectra. The mediation effect that the metal ions took part in the interaction has also been discussed in this paper. Based on different theoretical models of fluorescence quenching, the binding constant (K) and binding sites (n) of the interaction were determined and analyzed comparatively. The quenching mechanism of the binding reaction has also been discussed. The binding distance (r) and energy-transfer efficiency (E) between RT/RT-Co(II)/RT-Ni(II) and HSA were also obtained by virtue of the Förster theory of non-radiation energy transfer. The effect of RT acting on the HSA's conformation was analyzed by synchronous fluorescence spectroscopy. The result showed that the result calculated by different theoretical models is generally equivalent and RT bound HSA strongly by forming stable complex, which indicates that HSA under physiological conditions can act as a carrier for RT to be transported to exert effects. The microconformation of HSA changed significantly due to hydrophobicity change in the chemical environment of some fluorescence chromophores in the subdomain IIA and IIB of HSA. Metal ions Co(II) and Ni(II) can mediate RT-HSA interaction, making the binding of the drug to protein stronger, which indicates that Co(II) and Ni(II) can enhance rhaponticin's medical efficacy under physiological conditions.
Binding Sites ; Drug Interactions ; Energy Transfer ; Humans ; Hydrophobic and Hydrophilic Interactions ; Ions ; pharmacology ; Metals ; pharmacology ; Models, Molecular ; Protein Binding ; Protein Conformation ; Serum Albumin ; chemistry ; metabolism ; Spectrometry, Fluorescence ; Spectrophotometry, Ultraviolet ; Stilbenes ; chemistry ; metabolism

Microtubule is one of the key components of the cytoskeleton and plays an important role in the maintenance of cell shape and the process of signal transduction and mitosis. Due to the extreme importance of microtubule in the process of mitosis, tubulin becomes one of the most important targets for development of new anticancer drugs and tubulin inhibitors are used for the treatment of cancer nowadays. These inhibitors have antitumor activity by inhibiting or promoting the assembly of tubulin to microtubules and interfering the process of cell mitosis. This review summarized the research progress of the tubulin inhibitors, especially the introduction of the tubulin inhibitors of pharmacological activities and the progress of clinical research. Also, the development trend of these inhibitors is discussed.
Antineoplastic Agents ; chemical synthesis ; chemistry ; pharmacology ; Humans ; Microtubules ; drug effects ; metabolism ; Mitosis ; drug effects ; Molecular Structure ; Neoplasms ; drug therapy ; Stilbenes ; chemical synthesis ; chemistry ; pharmacology ; Structure-Activity Relationship ; Tubulin ; metabolism ; Tubulin Modulators ; chemical synthesis ; chemistry ; pharmacology

Vascular disrupting agents (VDAs) have presented a new kind of anti-cancer drug in recent years. VDAs take advantage of the weakness of established tumor endothelial cells and their supporting structures. In contrast to anti-angiogenic therapy, which inhibits the outgrowth of new blood vessels, vascular targeting treatments selectively attack the existing tumor vasculature. Here we summarized the anti-tumor activities, mechanisms and clinical applications of small molecule VDAs.
Angiogenesis Inhibitors ; chemistry ; pharmacology ; therapeutic use ; Animals ; Antineoplastic Agents ; chemistry ; pharmacology ; therapeutic use ; Bibenzyls ; chemistry ; pharmacology ; therapeutic use ; Diphosphates ; chemistry ; pharmacology ; therapeutic use ; Endothelial Cells ; drug effects ; Humans ; Molecular Structure ; Neoplasms ; drug therapy ; pathology ; Neovascularization, Pathologic ; Oligopeptides ; chemistry ; pharmacology ; therapeutic use ; Organophosphorus Compounds ; chemistry ; pharmacology ; therapeutic use ; Serine ; analogs & derivatives ; chemistry ; pharmacology ; therapeutic use ; Stilbenes ; chemistry ; pharmacology ; therapeutic use ; Tubulin Modulators ; chemistry ; pharmacology ; therapeutic use ; Xanthones ; chemistry ; pharmacology ; therapeutic use

Resveratrol, isorhapontigenin and pinosylvin, isolated from Gnetum parvifolium, and their analogues have been synthesized and tested for their inhibitory activity of HIV-1. Natural product 12a and analogues (12d, 12e, 12g) display significant inhibitory activity of HIV-1 replication. Among them, compound 12d (trans-3, 4, 5, 4'-tetrahydroxystilbene) exhibits the most potent anti-HIV-1 activity with an IC50 value of 1.84 micromol x L(-1).
Anti-HIV Agents ; isolation & purification ; pharmacology ; Cells, Cultured ; Drugs, Chinese Herbal ; isolation & purification ; pharmacology ; Gnetum ; chemistry ; HIV-1 ; drug effects ; physiology ; Inhibitory Concentration 50 ; Leukocytes, Mononuclear ; cytology ; virology ; Molecular Structure ; Plants, Medicinal ; chemistry ; Stilbenes ; chemical synthesis ; chemistry ; isolation & purification ; pharmacology ; Virus Replication ; drug effects