Based on previous report that the Chinese herb Ligustrum lucidum (LL) extract directly inhibited hepatitis C virus (HCV) replicase (NS5B) activity, the active components of LL extract to inhibit HCV NS5B activity and their inhibition mode were investigated in this study. LL extract was separated using ethyl acetate and thin layer chromatography (TLC). The inhibitory activity of separated fractions on HCV NS5B was analyzed by the inhibitory assay of NS5B activity. The results showed that only fractions 1 and 2 inhibited NS5B activity, and fraction 2 possessed higher inhibitory activity than fraction 1. HPLC analysis combined with inhibitory assays indicated that ursolic acid and oleanolic acid are the active components within fractions 1 and 2 to inhibit NS5B activity, separately. Moreover, oleanolic acid possessed higher inhibitory activity than ursolic acid. Further inhibition mode analysis found that both oleanolic acid and ursolic acid suppressed NS5B activity as noncompetitive inhibitors. The Ki values of ursolic acid and oleanolic acid were about 4.7 microg x mL(-1) (10 micromol x kg(-1)) and 2.5 microg x mL(-1) (5.5 micromol x kg(-1)), respectively. Taken together, these results demonstrated that oleanolic acid and ursolic acid suppressed NS5B activity as noncompetitive inhibitors, implying that the two natural products have potential value for HCV therapy.

Objective To explore the effect of R-spondin3 on the proliferation of neural stem cells (NSCs) and its mechanism in mice.Methods The mouse NSCs derived from the subventricular zone of E 14-15d CD 1 mice were confirmed by immunofluorescence assay.The NSCs after 3 passages of culture were chosen and randomly divided into 2 groups (V=1 mL).In the experimental group,0.8 μL of R-spondin3 with an initial concentration of 50 μg/mL was added (final concentration:40 ng/mL) while in the control group an equal amount of culture fluid was added.The proliferation of the cells in the 2 groups was detected by 5-Bromo-2-deoxy Uridine (BrdU) kits after the cells were treated by R-spondin3 for 6 hours.The protein expression of [β-catenin was measured by western blotting after the cells were treated by R-spondin3 for 4 and 8 hours.Results Under optical microscopy,the round and bright cells grew in culture medium and easily accumulated to become neurospheres.Immunofluorescence assay showed that over 90％ of the cells expressed Nestin and SOX2 and that some of them expressed NeuN or GFAP after induced differentiation.Brdu proliferation test showed that the proliferation rate of Brdu+/DAPI+ for the experimental group (1.56±0.03) was significantly higher than that for the control group (1.04±0.04) (P＜0.05).Western blotting showed that the expression levels of [β-catenin were increased at both 4h and 8h after treatment for the experimental group (1.09±0.10 and 1.20±0.13),significantly higher than those for the control group (0.56±0.05 and 0.83±0.04) (P＜0.05).Conclusions R-spondin3 can promote in vitro proliferation of NSCs in mice,which may be associated with activated Wnt/β-catenin signal pathways.

Objective To investigate the effect of galangin on proliferation and apoptosis of glioma cells in vitro.Methods (1) The glioma cells U87 and U25 1were divided into blank control group,DMSO group,100,200,300 and 400 μmol/L galangin treatment groups.MTT was used to study the effects of drugs on the proliferation of U251 and U87 cells.(2) Hoechest staining was used to observe cell apoptosis in the presence of different concentrations of galangin (0,100 and 200 μmol/L).(3) Flow cytometry was employed to detect the apoptosis of U251 and U87 cells in the presence of different concentrations of galangin (1 00 and 200 μmol/L).(4) Western blotting was employed to detect the expressions of apoptosis-related protein 3-Catenin,B-cell lymphoma-2 (Bcl-2),Bcl-2 related protein gene (Bax),cleaved-caspase-3,cleaved-caspase-9 and poly (ADP-ribose) polymerase (PARP) in the presence of different concentrations of galangin.Results (1) The proliferation of U251 and U87 cells was obviously inhibited atter 100,200,300 and 400 μmol/L galangin treatments,and dose-effect relation was noted.The concentrations of galangin at half rate of inhibition (IC50) were 281,321,276 and 229 μmol/L in U251 cells,and 289.4,261.1,247.4 and 225.3 μ mol/L in the U87 cells after 100,200,300 and 400μmol/L galangin treatments for 24 h.(2) Under the action of galangin,corresponding increase in apoptosis rates of U251 and U87 cells was noted following the increase of galangin concentrations (0,100 and 200 μmol/L),with significant differences (P＜0.05).(3) The detection of cell apoptosis by flow cytometry found similar changes.(4) Western blotting results indicated that galangin at the concentration of 0,100 and 200 μmol/L could significantly decrease the expressions of apoptosis-related protein 3-Catenin and Bcl-2,and increase the Bax,cleaved-caspase-3 and cleaved-caspase-9,and cleaved-PARP expressions;significant differences were noted between each two concentrations (P＜0.05).Conclusion Galangin can inhibit proliferation of glioma cells U251 and U87,and induce mitochondrial pathway of apoptosis via Wnt/β-Catenin signaling.

We developed a method to identify serological humoral immunodominant proteinic antigen of Mycoplasma hyopneumoniae (Mhp). After constructing the recombinant plasmid pGEX-6P-1-mhp366 and transforming it into Escherichia coli BL21(DE3), the recombinant GST-Mhp366 protein was expressed successfully. The lysates of the recombinant GST-Mhp366 and genetic engineering GST were added into glutathione coated plates and reacted with 17 positive sera or 13 negative sera. Meanwhile, the optimization of experimental conditions, including coated antigen, blocking buffer, dilutions of sera and second antibody were determined. The optimal concentration of the coated antigen was the original bacteria lysates without dilution, and the optimal blocking buffer contained 10% FBS and 2.5% skim milk in PBS. Besides, the working concentration of serum samples and the HRP-tagged rabbit anti-pig IgG secondary antibody were 1:500 and 1:40 000, respectively. Thus, an indirect ELISA was established for identification of immunodominant protein antigens of Mhp. Meanwhile, this method was confirmed by the identified serological humoral immunodominant proteinic antigen Mhp156 and Mhp364. This method can be used for identification of the candidate vaccine antigens on a genome-wide scale. Furthermore, it can lay the foundation for identifying the candidate vaccine antigens through colostra and the nasal mucosal secretions.

Cancer is one of the most important diseases threatening human health. Frequently-used traditional cancer treatment methods, like radiotherapy, chemotherapy and surgery, have serious toxic side effects and limitations. The widely-used drug delivery carriers (liposomes, nanoparticles, etc.) have also possessed many issues such as drug leakage and incomplete loading in the late clinical stage. Currently, using tumor-targeting vectors to deliver anti-tumor drugs or small molecules is one of the promising strategies for mediating safe and effective tumor therapy. In recent years, bacterial-derived non-replicating minicells, which are nanoscale non-nucleated cells produced during abnormal bacterial division, have got more and more attention. With a diameter of 200-400 nm, minicells have a large drug loading capacity. Meanwhile, the surface of minicells are able to be modified to load the assembly of antibodies/ligands that bind to tumor cell surface specific antigens or receptors, which can significantly improve tumor targeting of minicells. This tumor-targeting nanomaterials of minicells not only are used to deliver anti-tumor chemotherapeutic drugs, functional nucleic acids or plasmids encoding functional small molecules to mammalian cells, but also greatly increase drug loading and reduce drug penetration. Thus, the use of minicells combining with chemical therapy could help reduce the toxicity and maximize the effectiveness of the drug in the body. This paper summarizes the research and development of production purification, drug loading, tumor cells targeting, and internalization process of minicells, as well as its use in the delivery of anti-tumor drugs, to provide some information for the development and utilization of minicell carriers.
Animals ; Drug Carriers ; Drug Delivery Systems ; Humans ; Nanoparticles ; Neoplasms ; Plasmids