Enzyme-catalyzed Synthesis of Vitamin E Succinate Using a Chemically Modified Novozym-435

Vitamin E succinate was synthesized in organic solvents using a modified Novozym-435 as catalyst.In order to improve the catalytic performance of Novozym-435,the enzyme was modified using acetic anhydride, propionic anhydride and succinic anhydride separately.We found that both the hydrolytic activity and the thermal stability of the modified Novozym-435 were enhanced compared with the unmodified enzyme.The modified Novozym-435 catalysts were used to synthesize the succinate derivative of vitamin E.Compared with the native Novozym-435,the catalytic activity of the modified novozym-435 in promoting the synthesis of vitamin E succinate was dramatically increased,with the novozym-435 modified with succinic anhydride（N435-S）as the most active catalyst.Conditions for the synthesis of vitamin E succinate were also optimized.A mixture of tert-butanol and DMSO（volume ratio of 2︰3）was the most suitable medium for the reaction,whereas the appropriate molar ratio of vitamin E to succinic anhydride and reaction temperature were 1︰5 and 40°C,respectively.Under these reaction conditions,the yield of vitamin E succinate reached 94.4%.N435-S could be reused for five batches.

Effect of vitamin E succinate on the proliferation of human breast cancer cells

Objective：Tn investigate the growth inhibition and apoptosis induced by vitamin E suceinate （VES） on human breast cancer cells and to analyze the possible mechanism in this process. Methods： Human breast cancer cell line Bcap-37 was treated with VES for 12, 24 and 48 h at the concentrations of 5, 10and 20 μg/ml. Then MTT assay was employed to detect the inhibitory effect of VES on the growth of breast cancer cells. Flow cytometry was used to analyze the cell cycle and apoptosis. To find out whether the Fas/FasL pathway was involved in this process, RT-PCR and flow cytometry assay were used to detect the Fas expression at the mRNA and protein level. Results： VESexhibited a significant inhibitory effect on the growth of human breast cancer cells, presenting in a dose- and time-dependant manner. The apoptotic rate of Bcap 37 cells was 0.6%, rose to 21.0% and 37.5% after treated with VES for 24 and 48 h at the concentration of 20 μg/ml. Fas mRNA transcription was upregulated after VES treatment and cell surface Fas expression increased according to the flow cytometry assay. Concluslon：Significant growth inhibition and apoptosis are induced in human breast cancer cells after treated with VES. The modulation of Fas/FasL pathway may related to the upregulation of Fas molecule on the cancer cell surface.

Research of vitamin E succinate combined with paclitaxel on the apoptosis of Her-2 over-expressing breast cancer cells

Objective： The aim of this study was to detect apoptosis rates of Her-2 overexpression breast cancer cells, which were administrated with vitamin E succinate （VES） combined with paclitaxel at different dosages, or administrated alone; to discuss the mechanism of their actions. Methods： Using immunohistochemical method to detect Her-2 expression of MDA- MB-453 cells. Using TUNEL assay to detect apoptosis rates of MDA-MB-453 ceils, with the concentrations at 10, 20 mg/L of VES and 50, 100 nmol/L of paclitaxel, and also combined together for 24 or 48 h. Then compared apoptosis action of various combinations. Results： The expression rate of 95% Her-2 was interval （63.32%, 69.60%）; VES and paclitaxel both induced apoptosis of MDA-MB-453 cells, and it is dose to time dependence. It was strongest in apoptosis at 10 mg/L VES and 100 nmol/L paclitaxel in MDA-MB-453 cells 48 h later. Conclusion： VES and paclitaxel both induced apoptosis of MDA-MB-453 cells. It is stronger when the two drugs are administrated together. The mechanism is probably related to reduction of bcl-2 expression, so as to be more sensitive to paclitaxel. Synergistic effect is also possible for the two drugs influence tumor cells in different growing phases.

纪念莫斯科大学艺术史教育125周年(三)——第二次世界大战之后的人员和科研变革

在莫斯科大学重建艺术学部的工作开始于困难的战争年代。【1】1941年莫斯科大学撤往阿什哈巴德,这时哲学文学历史研究所和大学合并。在重建的语言学系的各教研室中就包括艺术学教研室。位于阿什哈巴德的大学,后来在1942夏被迁往斯韦尔德洛夫斯克,涅多希温、科贝林娜、加布里切夫斯基等人主持开课。

Preparation, characterization and evaluation of multi-component-loaded liposomes containing Tat-TOS, phospholipase D inhibitor and doxorubicinPreparation, characterization and evaluation of multi-component-loaded liposomes containing Tat-TOS, phospholipase

In the present study, we aimed to co-load the α-TOS conjugate Tat-TOS with the phospholipase D inhibitor FIPI and the antitumor drug doxorubicin（DOX） in a liposome delivery system for antitumor metastasis. Firstly, Tat-TOS was synthesized by solid-phase synthesis, and its structure was confirmed. The ability of free and liposomal Tat-TOS to induce apoptosis in vitro was evaluated by flow cytometry. Biodistribution of Tat-TOS-loaded liposomes was investigated by a molecular imaging system. Multi-component-loaded liposomes modified with Tat-TOS containing FIPI and DOX was prepared by thin film dispersion method in combination with p H gradient method and post-insertion method. Physicochemical properties were determined, and the in vitro uptake ability of the formulations was evaluated. The results showed that the prepared liposomes were characterized by a uniform particle size distribution and small particle size. The encapsulation efficiency of FIPI and DOX exceeded 85%. Both free and liposomal Tat-TOS significantly improved the activity of inducing apoptosis of tumor cells. The liposomes modified with Tat-TOS were apparently accumulated in normal lung tissue and tumor metastasized lung. Multi-component-loaded liposomes exhibited the strongest cell uptake capacity, suggesting a stronger anti-metastatic effect and anti-tumor activity in vivo.

Enhanced water solubility, antioxidant activity, and oral absorption of hesperetin by D-α-tocopheryl polyethylene glycol 1000 succinate and phosphatidylcholine

Hesperetin,an abundant bioactive component of citrus fruits,is poorly water-soluble,resulting in low oral bioavailability.We developed new formulations to improve the water solubility,antioxidant activity,and oral absorption of hesperetin.Two nano-based formulations were developed,namely hesperetin-TPGS(D-α-tocopheryl polyethylene glycol 1000 succinate)micelles and hesperetin-phosphatidylcholine(PC)complexes.These two formulations were prepared by a simple technique called solvent dispersion,using US Food and Drug Administration(FDA)-approved excipients for drugs.Differential scanning calorimetry(DSC)and dynamic light scattering(DLS)were used to characterize the formulations’physical properties.Cytotoxicity analysis,cellular antioxidant activity assay,and a pharmacokinetic study were performed to evaluate the biological properties of these two formulations.The final weight ratios of both hesperetin to TPGS and hesperetin to PC were 1:12 based on their water solubility,which increased to 21.5-and 20.7-fold,respectively.The hesperetin-TPGS micelles had a small particle size of 26.19 nm,whereas the hesperetin-PC complexes exhibited a larger particle size of 219.15 nm.In addition,the cellular antioxidant activity assay indicated that both hesperetin-TPGS micelles and hesperetin-PC complexes increased the antioxidant activity of hesperetin to 4.2-and 3.9-fold,respectively.Importantly,the in vivo oral absorption study on rats indicated that the micelles and complexes significantly increased the peak plasma concentration(Cmax)from 2.64μg/mL to 20.67 and 33.09μg/mL and also increased the area under the concentration–time curve of hesperetin after oral administration to 16.2-and 18.0-fold,respectively.The micelles and complexes increased the solubility and remarkably improved the in vitro antioxidant activity and in vivo oral absorption of hesperetin,indicating these formulations’potential applications in drugs and healthcare products.