A series of E and Z-isomers of 3-（4＇-substituted benzylidene）-indolin-2-one derivatives were synthesized and separated. Based on their 1H NMR characterization, an unusual counterintuitive deshielding phenomenon for the protons presenting in the shielding zone of phenyl ring was observed and analyzed for the first time.
The root of Hedysarum multijugum（RHM） is recorded as a folk herbal medicine in China and is sometimes used as a substitute for Hedysari Radix, which is a famous traditional Chinese medicine derived from the roots of Hedysarum polybotrys. In the present study, a sensible, reliable, and reproducible HPLC-DAD fingerprint analysis method for RHM was developed and then subsequently applied to analyze RHM samples from different origins. The chemical constituents of the RHM samples were generally consistent, although it was slightly affected by the local environment of the plant. In addition, the chemical constituency of RHM was shown to be significantly different from that of Hedysari Radix, suggesting that RHM is not suitable as a substitute for Hedysari Radix, at least from the chemical point of view.
Rho GTPases play an important role on the regulation of cytoskeleton, which can affect the cell morphogenesis, cell migration, endocytosis and vesicle transport by controlling the growth and maintenance of microfilaments and microtubules. It has been known that regulation of cell cytoskeleton is inseparable from the cell uptake of nano-medicine or nano-drug delivery systems. However, only few studies have focused on the impacts of Rho GTPases on cell uptake of nano-medicine or nano-drug delivery systems. This study selected single-walled carbon nanohoms （SWCNHs）, which have emerged as promising drug delivery systems, to explore the impacts of Rho GTPases on cell uptake of nano-drug delivery systems. SWCNHs were oxidized with concentrated nitric acid and prepared into nano dispersion by ultrasonic dispersion. Confocal laser scanning microscope （CLSM） and transmission electron microscopy （TEM） were used to observe the cell uptake and intracellular distribution of nanoparticles after incubated A549 cells with the dispersion mentioned above. Mechanism of cell uptake was assessed using various inhibitors. The results showed that the cell uptake of oxSWCNHs was significantly reduced when RhoA was inhibited. The oxSWCNHs were internalized through clathrin-mediated endocytosis and mainly positioned in lysosomes ofA549 cells.
Cationic lipids have been applied to siRNA delivery for tumor therapeutics. However, the excess positive charges of these nanoplexes may lead to high cytotoxicity and nonnegligible immunogenicity both in vitro and in vivo, which limited the applications of gene drugs. We constructed multi-component lipoplex to delivery 3＇,3＂-bis-peptide-siRNA conjugate （pp-siRNA） by the treatment of melanoma. Based on the previous studies that the gemini lipid （CLD） encapsulated pp-siRNA, a novel neutral cytosin-l-yl- lipid （DNCA） was considered to replace a certain ration of CLD by hydrogen bonds and ~t-n stacking for reducing the cytotoxicity. It similarly retained in both the loading efficiency and targeted mRNA inhibition when DNCA was accounted for 40% in the lipoplex, with lower toxicity. Moreover, CLD/DNCA/pp-siRNA nanoplex could be uptake in A375 cells and internalized mainly by macropinocytosis and caveolin-mediated endocytosis. Besides, 90% CLD/DNCA/pp-siRNA nanoplexes presented the highest efficient knockdown for the mutant B-RAF mRNA （-80%）. All the results demonstrated that the mixed cationic and neutral lipids could efficiently realize the delivery of pp-siRNA and had potential application for cancer therapy.
Mangiferin is a natural plant polyphenol with a structure of xanthone C-glycoside and it displays a wide spectrum of pharmacological activities. Investigation of the metabolites of mangiferin is valuable in studying the mechanisms of its various pharmacological properties and developing novel drugs from the mangiferin derivatives. Among the metabolites of mangiferin, mangiferin-7-O-β-D-glucuronide has been reported as the phase Ⅱ metabolite of mangiferin. Herein we described the first semi-synthesis of mangiferin-7-O-β-D-glucuronide with the natural product mangiferin as the starting material. In this work, we adopted several regioselective protection procedures to distinguish the different hydroxyl groups in the structure of mangiferin, and we accomplished the glycosylation under the phase-transfer catalysis conditions. In this method, we efficiently synthesized the glucuronide derivative of mangiferin in 10 steps with highly regioselective protection.
