Aim To investigate the effects of isoliquiri-tigenin(ISL)on C6 glioma cell proliferation and differ-entiation.Methods C6 glioma cells’viability and proliferation were respectively measured by SRB test. Colony formation of C6 glioma cells from different groups was assayed.After culturing the cells from each group,giemsa staining was used to observe cell mor-phology.RT-PCR was applied to detect mRNA expres-sion of GFAP.Western blot was applied to detect the expression of GFAP.Results ISL effectively inhibited the viability of C6 glioma cells when compared with the control group in a concentration-dependent manner (P<0.01).The morphological observation under light mi-croscope showed that:in the control group,most of the undifferentiated C6 cells showed long fusiform and po-lygonal shape.Compared to the control group,the C6 cells treated with ISL revealed alteration in morphology such as astrocytes with smaller smooth,round body and much finer longer,tapering processes.The cloning for-mation rate detection revealed that:the colonies in the control group semerged earlier and were larger than those experimental ones,the cloning formation rate was higher,while almost no effective cells colony emerged in ISL treated groups(P <0.01 ).Western blot and RT-PCR analysis showed that GFAP expression in the ex-perimental groups increased(P <0.01).Conclusion ISL may inhibit the proliferation of C6 glioma cells and induce their differentiation.

Aim To explore the protective effects of lithium chloride ( LiCl ) on neurous injuries and phos-phorylation of tau protein at serine262 induced by okada-ic acid( OA) . Methods The neuroblastoma SK-N-SH cells were differentiated by all-trans-retinoic acid ( AT-RA) . The differentiated SK-N-SH cells were treated with OA to establish the Alzheimer′s disease cellular model. SK-N-SH cells′ viability and proliferation were measured by SRB test. Giemsa staining was used to observe cell morphology. The neurite length of SK-N-SH cells was measured by Image-Proplus software. Syn-aptophysin and phosphorylated tau protein at serine262 expression levels were tested by Western blot. Results The SK-N-SH cells which were treated with 10 μmol ·L-1 ATRA for 7 days displayed mature neuronal fea-tures. The synaptic length of SK-N-SH cells became longer. And the levels of serine262 phospho-tau was sig-nificantly elevated. 20~100 nmol·L-1 OA effectively inhibited the viability of differentiated SK-N-SH cells in a concentration-dependent manner and in a time-de-pendent manner. The OA treatment induced obvious synaptic atrophy in differentiated SK-N-SH cells. And the phosphorylation level of tau protein serine262 also greatly increased. The pretreatment with 10 mmol · L-1 LiCl significantly ameliorated the synaptic atrophy, the decrease of synaptophysin expression and the in-crease of tau phosphorylation at serine262 induced by OA in differentiated SK-N-SH cells. Conclusion LiCl could effectively inhibit OA-induced synaptic atro-phy in differentiated SK-N-SH cells, and it could also result in the increase of synaptophysin expression and the decrease of the phosphorylation of tau protein at serine262 .