Latest ArticlesBeads, a novel drug delivery system self-assembled by cyclodextrins (CDs) and oil, has potential applications in the solidification of oil drugs and improving the bioavailability of lipid-soluble drugs. However, very few researches were dedicated to the mechanism of beads formation. In this study, three-dimensional structures of beads were visualized and investigated using synchrotron radiation X-ray microcomputed tomography (SR-μCT). The structural changes of beads attributed by drying process were analyzed and confirmed via visualization results of SR-μCT. Productively, it was proposed that Pickering emulsion droplets obtained during beads formation process were spatially localized orderly. Moreover, the effects of loading lipid soluble drug, namely, vitamin K1, on the structural changes of beads were also analyzed. It is well known that the surface tension of oil phase could be changed by the addition of lipid soluble constituents. It was reasonable that the three-dimensional structure of beads might be altered during the drug loading of vitamin K1 into the beads. However, although the morphologies of beads were changed to some extent, the ordered Pickering emulsion droplets during the process of beads formation was successfully illustrated based on the SR-μCT results. Conclusively, according to the three-dimensional structural analysis of the beads, this study revealed the organized architecture for Pickering emulsion droplet assembly and beads formation in cyclodextrin semi-inclusion complex, which significantly complements the formation mechanism of beads, and provides a structural basis for the further study of beads.
The effects of catechin on inflammatory response of BV-2 cells were investigated using the lipopolysaccharide (LPS) model. BV-2 cells were incubated with LPS (1 mg·L-1) for 12 h in the microglia inflammatory model in vitro. After catechin and LPS co-incubation for 12 h, MTT, ELISA and Western blot were used to detect cell viability, cytokines, cell migration and protein expression. In addition, transwell assay was conducted to investigate the effect of catechin on cell chemokaxis. Catechin did not show any cytotoxicity effect on BV-2 cells, but reversed the change in cell morphology and inhibited the release of TNF-α and IL-1β, cell chemotaxis and phosphorylation of NF-κB/p65. In conclusion, Catechin could inhibit the LPS-induced inflammatory response in BV-2 cells.
The calcineurin B-like protein (CBL)-interacting protein kinase (CIPK) plays a vital role in the growth, development, and stresses adaptation in plants by interaction with the calcium signaling. In this study, four full length cDNAs of CIPKs genes, namely DoCIPK1, DoCIPK2, DoCIPK3 and DoCIPK4 (GenBank accession No. KT957557, KT957558, KT957559 and KT957560, respectively) were cloned from the rear and medicinal plant, Dendrobium officinale, by rapid amplification of cDNA ends (RACE) for the first time. The corresponding encoded proteins, consisting of 473, 449, 451 and 440 amino acids (aa), respectively, with a molecular weight of 53.50, 50.93, 51.50 and 50.16 kDa, and an isoelectric point (pI) of 7.99, 9.25, 8.81 and 9.11, respectively, shared 70%-90%, 69%-80%, 78%-93%, and 66%-82% identities CIPKs with various plants. Each deduced protein contained a conserved protein kinase domain (respectively at 21 -275, 14-268, 16-271 and 12-266 aa position), a CIPKs family characteristic NAF/FISL domain (respectively at 335-391, 313-370, 310-369 and 305-362 aa position) and some functional motifs. The four DoCIPK proteins, without signal peptide or transmembrane region, were located in the plasma membrane and endoplasmic reticulum at the subcellular level. The three dimensional structure of the proteins were similar to that of Arabidopsis AtCIPK24. DoCIPK1 and DoCIPK3 were respectively clustered in the group E and A of the Arabidopsis and rice CIPK evolutionary tree, while DoCIPK2 and DoCIPK4 belonged to group C. The relative expression of DoCIPK1 showed no significant difference in the leaves and stems, and its transcripts in the roots was 0.35 fold over that in the leaves. The abundance of DoCIPK3 transcripts in the stems and the roots were 3.36 fold and 3.47 fold higher, respectively, than those in the leaves. DoCIPK2 exhibited similar expression pattern to DoCIPK4. Their relative expression in the leaves and the stems had no apparent difference, and the transcript levels were higher in the roots than that in the leaves, with 2.08 fold and 7.86 fold, respectively. Cloning, bioinformatics analyses, and expression patterns of the four DoCIPK genes provide a basis for functional elucidation of these genes further during the physiological responses in D. officinale.
This study was to investigate the effect of RORα activator SR1078 on ovarian cancer cells and its molecular mechanism in vitro. The survival rate of HeyA8 and Hey cells was detected by MTS assay; the apoptosis and cells cycle distribution after SR1078 treatment and the effect of p53 siRNA or PFT-α and PFT-β of p53 inhibitors on SR1078-induced apoptosis of HeyA8 or Hey cells were analyzed by flow cytometry. Western blot was used to detect the effect of SR1078 and p53 siRNA on the expression of p53 protein and the effect of p53 inhibitors alone or in combination with SR1078 on the expression of p53, p-p53 and its downstream pro-apoptotic protein Noxa. The results showed that SR1078 significantly reduced the cell viability and induced apoptosis in HeyA8 and Hey cells. In addition, SR1078 up-regulated the protein expression of p53 and Noxa, and p53 suppression led to significant inhibition of SR1078-induced apoptosis and the expression of Noxa in ovarian cancer cells. In summary, SR1078 induced apoptosis of ovarian cancer cells by activation of p53 signaling pathway.
As a new generation of anti-tumor drugs, taxanes has a good clinical efficacy in the treatment of ovarian cancer, breast cancer, non-small cell lung cancer, head and neck cancer. However, low bioavailability of oral administration from low water solubility and low permeability significantly limited the development of their oral applications. Currently, the marketed preparations were non-oral drug preparations, and the injection contained a large number of surfactants (cremophor EL or Tween 80) and organic solvents (ethanol), which could result in fluid retention, hypersensitivity and other side effects, as well as poor compliance. Oral preparation will be an ideal form for development of taxanes medicines. According to the research by our and other groups in recent years, we investigate the technical strategies enhancing the water solubility and absorptive permeability to improve their oral bioavailability. Among them, we emphasize the application prospects of crystallography technology, and provide a theoretical basis to guide future research in the development of oral preparations for taxanes.
A new dihydroflavone:mirabiflavone (1), together with two known compounds were isolated from the ethyl acetate extract of the roots of Mirabilis himalaica by using various chromatographic techniques, such as silica gel column, Sephadex LH-20 column, and semi-preparative HPLC. Their structures were elucidated as syringaresinol (2) and lariciresinol (3) by spectroscopic analysis. Compounds 2 and 3 were isolated from this plant for the first time.
Two new diarylheptane derivatives were isolated from Rhizoma Zingiberis by Diaion HP-20, MCI Gel CHP-20, ODS, silica gel column and reverse phase semi-prepared high performance liquid chromatography. Their structures were elucidated by spectrum technology (MS, UV, IR, NMR), which were identified as 3-keto-5R-ethoxy-1-(3-methoxy-4-hydroxyphenyl)-7-(3, 4-dihydroxyphenyl)heptane (1) and 3-keto-5R-ethoxy-1-(3-methoxy-4-hydroxyphenyl)-7-(3-methoxy-4, 5-dihydroxyphenyl)heptane (2). Compounds 1 and 2 are new compounds.
Follow-on drug approach is to follow-up and make-up of the innovation of pioneering drugs. Since the millennium new molecular entities (NME) have experienced ample optimization, and the patents have claimed in wide ranges, as well as the drug administration requires NME being superior or non-inferior to the existing drugs of the same class. These situations have made the space of follow-on drug innovation narrow and smaller than before. The follow-on drug approach can be concisely differentiated into two aspects:one is to start from the chemistry of small molecules, which are performed with a niche-targeting manipulation to optimize the safety, efficacy and (or) convenience for dose superior to the existing drugs; another proceeds with the macromolecule targets. Based on the knowledge of the mechanism of action or of target mutation, active compounds are constructed through complementary binding or by the reaction mechanism. In this article successful examples are briefly described to illustrate the features of follow-on drug approach.
Metabolic transformation in vivo is a critical approach in the study of toxicity, but real-time dynamic observation of the transformation is difficult. We proposed that zebrafish toxicity/metabolism synchronization may be used in the analysis of toxicity of Folium Epimedium (Yinyanghuo for Chinese, YYH) and the toxicity may be reduced by Radix Morindae Officinalis (Bajitian for Chinese, BJT). Healthy zebrafish embryos 1 day post fertilization (1 dpf) were exposed to different concentrations of YYH, total flavonoids of YYH (YTF), representative flavonoids (epimedin C and icariin) and their respective in combination with BJT. Death numbers of the embryos or larvals were counted during 1-5 days after dosing (2-6 dpf); embryonic micro-morphology of zebrafish (3 dpf) was observed and pictures were taken. The blank vehicle (0.4% DMSO) was used in the control group, and LC50 value of 2 to 6 dpf was calculated by SPSS16.0. A relative safe concentration was sampled every day to analyze the dynamic metabolites changes of major flavonoids of YYH. The results showed that epimedin A/B/C (EA/EB/EC) and icariin, the major flavonoids of YYH, were dynamically transformed into major metabolites of sagittatoside C (SC) and baohuoside I (BI) by zebrafish. BI was mainly derived from EA, EB and icariin. Neither original form nor their metabolite BI can cause zebrafish poisoning. SC was mainly derived from EC, and its accumulation was closely related to the toxicity of YYH, YTF and EC. After combination with BJT, the metabolism of EC was slowed down and the toxicity was alleviated. Zebrafish toxicity/metabolism synchronization revealed that the toxicity of EC of YYH was increased after metabolism into SC, which maybe the key potential poisonous factor of YYH, and BJT can reduce the toxicity by slowing down the metabolism rate of EC. The data provides new ideas and methods in the study of toxic substances in Chinese medicine and mechanism of detoxicity by combination.
The New Delhi metallo-β-lactamase-1 (NDM-1) was first reported in 2010, detected in a Klebsiella pneumoniae isolate from a Swedish patient of Indian origin. It has recently attracted extensive attention for its biological activities to catalyze the hydrolysis of almost all of β-lactam antibiotics. The gene for NDM-1 can spread from one strain of bacteria to another by horizontal gene transfer. The most troubling aspect is that there are currently no clinically available inhibitors to block the metallo-β-lactamase action. Therefore, there is urgent need to develop new NDM-1 inhibitors, which can protect β-lactam antibiotics from the hydrolysis effect of NDM-1. In this review, the current research, drug-assistant mechanism and potential NDM-1 inhibitors are summarized.