Ginkgo biloba extract 50 inhibited beta-amyloid-induced oxidative stress in rats' hippocampal neurons: an experimental study / 中国中西医结合杂志

<p><b>UNLABELLED</b>OBJECTIVE To study the in vitro effect and mechanism of Ginkgo biloba Extract 50 (GBE50) for inhibiting beta-amyloid (Abeta)-induced oxidative stress in rats' hippocampal neurons.</p><p><b>METHODS</b>The primary hippocampal neurons were cultured in vitro and divided into 4 groups, i. e. the normal control group (Ctrl), the Abeta group, the propanediol control group (PDO), and the six GBE50 concentrations groups (5, 10, 25, 50, 100, and 200 microg/mL). Excepted the Ctrl group, neurons were induced to oxidative stress by 20 gmolLAbeta25-35. The MTT and fluorescent probes labeling were used to observe the effect of GBE50 with different concentrations on the cell viability and the generation of intracellular reactive oxygen species (ROS) in neurons. Furthermore, Western blot was used to detect the cytoplasmic/total cytochrome C (Cyto C) ratio and total intracytoplasmal Cyto C, and the effect of the expression of oxidative stress-related protein Cyto C and activated Caspase-3 in three GBE50 concentrations groups (25, 50, and 100 microg/mL).</p><p><b>RESULTS</b>Compared with the Ctrl group, the cell vitality was obviously lowered and intracellular ROS generation significantly increased after induction of 20 micromol/L Abeta25-35 (both P < 0.05). Compared with the Abeta group, the cell vitality was evidently improved after treated with different GBE50 doses. Except for 10 microg/mL, the cell vitality could be obviously elevated along with increased drug concentrations (P < 0.05). Meanwhile, the intracellular ROS generation decreased significantly in each GBE50 dose groups (P < 0.05). Abeta could increase the cytoplasmic/total Cyto C ratio and enhance the activated Caspase-3 expression significantly (P < 0.05). Compared with the Abeta group, among the three concentrations of GBE50, the Cyto C ratio was obviously lowered in the 100 microg/mL GBE50 group (P < 0.05), and the expression of activated Caspase-3 significantly decreased in 50 microg/mL and 100 microg/mL GBE50 groups (P < 0.05).</p><p><b>CONCLUSIONS</b>20 micromol/L Abeta25-35 could induce the generation of intracellular ROS in hippocampal neurons. GBE50 could inhibit Abeta induced intracellular oxidative stress of neurons through lowering the cytoplasmic/total Cyto C ratio and inhibiting the activation of apoptosis protein Caspase-3 expression.</p>

[Construction, expression and immunogenicity of eukaryotic vectors based on goat pox virus P32 gene].

The full-length P32 gene and the truncated P32 gene (MP-32) were amplified from the recombinant plasmid pMD-P32 by polymerase chain reaction (PCR) and cloned into pcDNA3. 1(+) and pcDNA3.1-CpG respectively. The recombinant plasmids (pcDNA3.1-P32, pcDNA3.1-CpG-P32 and pcDNA3. 1-CpG-MP32) were transfected into BHK-21 cells by using lipofectin. The expressed P32 protein was confirmed by indirect immunofluorescence assay (IFA). The BALB/c mice were immunized with these recombinant plasmids by intramuscular injection. The specific antibodies aginst CPV were detected by ELISA kit weekly. The murine splenic T lymphocyte subgroups CD4+ and CD8+ were detected by flow cytometry. Results showed that the P32 protein was expressed successfully in vitro. After 2 weeks post im munization, the specific IgG antibodies against CPV were detected in the vaccinated mice. The percentage of CD4+ /CD8+ T cells was significantly higher than that of the control. In conclusion, these constructed eukaryotic vectors could induce humoral and celluar immune responses in mice.