ABSTRACT
This article was aimed to investigate the cell proliferation , cell apoptosis and its related molecular mechanisms of the human gastric carcinoma cell line BGC-823 in v itro after treatment with cinnamaldehyde . The MTT Assay demonstrated the inhibitory effect of cinnamaldehyde . And the Flow Cytometry was used to determine its induction of cell apoptosis. The Hoechst 33342 was used to observe morphological changes during apoptosis . Moreover , quantitative real time PCR and western blot analysis were used to detect the effect of cinnamaldehyde on human gastric carcinoma cell line BGC-823 . The results showed that compared with the control group , cinnamaldehyde had inhibitory effect on human gastric carcinoma cell line BGC-823 ( P <0 . 01 ) . It showed that cinnamaldehyde induced apoptosis through the downregulation of Bcl-2 , Bcl-xL and Survivin expression , upregulation of Bax and Bak expression , downregulation of Bcl-2 and Procaspase-3 , and upregulation of BAX . It was concluded that cinnamaldehyde had inhibitory effect on the proliferation of human gastric carcinoma cell line BGC-823 and induced apoptosis . It may be related to the activation of the endogenous apoptosis pathway .
ABSTRACT
Objective To identify the imbalance of T cell-specific transcription factors T-bet/GATA-3,and to explore the modulation with dexamethasone and imiquimod in CD4+T cells from ovalbumin (OVA)sensitized mice.Methods CD4+T cells were obtained fromsingled-cell suspension of spleen(after lysis of RBC).ELISA assay was used to detect the concentrations of IL-4,IL-5 and IFN-γin superna tants and cell pellets,and the expression of T-bet and GATA-3 was detected by Western blot.Resuits In the control group,tIle low levels of IFN-γ were detected in the supernatants during 24 h.In OVA treatment group,the concentrations of IL-4,IL-5 were increased significantly,and the concentrations of IFN-γ were always low in the supernatants.In the dexamethasone treatment group,the concentrations of IFN-γ,IL-4 and IL-5 were all low in the supernatants during 24 h.In the imiquimod treatment group,the concentrations of IFN-γ were increased significantly,and the concentrations of IL-4 and IL-5 were decreased in the super natants.It worked at 6 h,and achieved the peak at 12 h,lasted over 24 h.In the control group,the expres sions of T-bet and GATA-3 were detected in CD4+T cells during 24 h.In OVA treatment group,the expressions of T-bet were decreased,and that of GATA-3 were increased rapidly in CD4+T cells.In dexam ethasone treatment group,the expressions of T-bet were always low in CD4+T cells,and that ofGATA-3 were no change during 24 h.In imiquimod treatment group,the expressions of T-bet were increased,andthat of GATA-3 were decreased in CD4+T cells.The protein expressions worked at 6 h.and achieved the peak at 12 h,lasted over 24 h.Conclusion The imbalance T cell-specific transcription factors T-bet/GA-TA-3 contributes to both high expression of GATA-3 and low expression of T-bet in CD4+T cells from OVA sensitized mice.Dexamethasone treatment inhibits the expression of T-bet in CD4+T cells and has no func tion in GATA-3.Imiquimod treatment modulates key master switches GATA-3 and T-bet that results in com mitting T helper cell to a TH 1 phenotype and imiquimod may play a key role in the regulation of TH2 cytokine responses in asthma.
ABSTRACT
Objective To characterize the dimerization and the antigenicity of the ORF2 polypep-tide of hepatitis E virus (HEV, genotype 4). Methods HEV ORF2 gene was cloned from the serum of a patient with hepatitis E. The genotype was determined by sequencing. Three ORF2 polypeptides differing in size and other polypeptides with point mutations were produced in E. coli. The recombinant polypeptides were purified and analyzed by SDS-PAGE and Western blot. Results The ORF2 polypeptide containing 459-607 amino acid formed homedimer even in 8 mol/L urea. The truncated polypeptides containing amino acid 472-607 or 459-594 formed monomer only. The mutations at amino acid 562 or 595 disrupted the ho-modimer, whereas the mutations at amino acid 476 or 580 did not. Anti-HEV from hepatitis E patients only reacted with the homodimer form of the polypeptide 459-607 and did not react with monomer or tnmcated pol-ypeptides. Conclusion The amino acid 459-607 of HEV ORF2 is essential for dimerization of the ORF2 polypeptide. Residues at amino acid 562 and 595 are critical for the dimerization. The antigenicity of the polypeptide 459-607 mainly depends on its homodimer form.