Quercetin promotes neurite growth through enhancing intracellular cAMP level and GAP-43 expression / 中国天然药物

The present study was designed to investigate the role of quercetin on neurite growth in N1E-115 cells and the underlying mechanisms. Quercetin was evaluated for its effects on cell numbers of neurites, neurite length, intracellular cAMP content, and Gap-43 expression in N1E-115 cells in vitro by use of microscopy, LANCE(tm) cAMP 384 kit, and Western blot analysis, respectively. Our results showed that quercetin could increase the neurite length in a concentration-dependent manner, but had no effect on the numbers of cells. Quercetin significantly increased the expression of cellular cAMP in a time- and concentration-dependent manner. The Gap-43 expression was up-regulated in a time-dependent manner. In conclusion, quercetin could promote neurite growth through increasing the intracellular cAMP level and Gap-43 expression.

Immunogenicity of recombinant DNA vaccine that coded for the neurite growth inhibitors / 中华神经医学杂志

Objective To detect the immunogenicity of the recombinant DNA vaccine that encoded for neurite growth inhibitors: Nogo-A, oligodendrocyte myelin glycoprotein (OMgp), tenascin-R (TN-R) and myelin-associated glycoprotein (MAG) after the nerve injury under the help of pAdEasy, a kind of adenovirus plasmid being the vector of the DNA. Methods Sixteen 5-w-old Lewis rats were randomized into DNA vaccination group (vaccine group) and pAdEasy group. Rats in the vaccine group were immunized once weekly for a consecutive 8 w by bilateral injection of the recombinant plasmid into the musculus tibialis. The immunized animals in the 2 groups were exsanguinated each time before the vaccination for sera collection, and the qualitation and quantitation of the antibodies in the serum were detected by Dot-blot analysis and ELISA. Results The vaccine group could produce fusion-protein antibodies against Nogo-A, MAG, OMgp and TN-R at the 6th w of vaccine injection, while pAdEasy group could not. The valency of antiserum was shown by ELISA as 1:1 000 000 at the 6th w of vaccine injection and kept this level stably. Conclusion The DNA vaccine exclusively induces the generation of the fusion-protein antibodies against Nogo-A, MAG, OMgp and TN-R in vivo, which controls the favorable immunogenicity.

The Effects of Venlafaxine on Neurite Growth of PC12 Cells

OBJECTIVES: The purpose of this study is to examine the effects of venlafaxine, one of novel antidepressant drugs, on neurite growth in PC12 cells. METHODS: PC12 cells were cultured with NGF for eight days. Then different concentrations(0micrometer, 1micrometer, 5micrometer) of venlafaxine were mixed with cultured PC12 cells. After 24 hours and 48 hours of culture, we compared the effects of venlafaxine on the total length of neurites of cultured PC12 cells between no venlafaxine treated group(0micrometer) and venlafaxine treated groups(1micrometer and 5micrometer). Additionally, we studied the concentration-dependent effect of venlafaxine on differentiation in PC12 cells. RESULTS: Experimental results showed that 1) the mean length of neurites in 1micrometer and 5micrometer venlafaxine treated group was more increased than no venlafaxine treated group(p=0.002). 2) the length of neurite in 5micrometer venlafaxine treated group was more elongated than 1micrometer venlafaxine treated group(p=0.046). 3) the length of neurite in 6micrometer venlafaxine treated group was more elongated than all the other concentrations in our experiment. Above 6micrometer, the length of neurite was shortened in inverse proportion to the concentration of venlafaxine. CONCLUSIONS: This results suggest that venlafaxine, one of novel antidepressant drugs, promotes the differentiation of neuron. This study is believed to be a first step toward understanding the molecular and cellular mechanisms of antidepressant treatment.