格列本脲对胶质母细胞瘤活性及细胞内酸碱平衡的影响

目的:探讨格列本脲对胶质母细胞瘤活性及细胞内酸碱变化的影响。方法:使用不同浓度的格列本脲(Glib)处理人胶质瘤细胞株U251和U87,通过CCK-8法筛选有效剂量;随后将实验分成对照组和药物处理组,划痕实验检测细胞迁移情况,细胞p H指示荧光探针检测细胞内p H变化,Western blot测定内向整流钾离子通道4.1(Kir4.1)和单羧酸转运蛋白1(MCT1)的表达情况。结果:CCK-8法检测结果显示,Glib作用于U251细胞和U87细胞48 h的半数抑制浓度(IC50)分别为400.20μmol/L和553.70μmol/L,且在100~1 600μmol/L的浓度区间范围内,Glib抑制U251细胞活力,在50~1 600μmol/L的浓度区间范围内,Glib抑制U87细胞活力,两者均呈浓度依赖性(P0.05);与对照组相比较,Glib不仅能够抑制细胞迁移(P0.05),抑制作用与药物浓度呈正相关(P0.05),而且使实验组细胞内荧光强度减弱(P0.05),提示随着药物浓度的增高,细胞内p H值逐渐下降(P0.05);实验组细胞的Kir4.1和MCT1蛋白含量明显降低,均有浓度依赖性(P0.05)。结论:Glib在一定剂量范围内通过下调Kir4.1和MCT1表达诱导细胞内环境酸化,抑制胶质瘤细胞生长。

Effect of glibenclamide on viability and acid-base equilibrium of glioblastoma cells

AIM: To investigate the effect of glibenclamide (Glib) on the viability and acid-base equilibrium of glioblastoma cells. METHODS: U251 cells and U87 cells were treated with Glib at different concentrations. The inhibitory rates were detected by CCK-8 assay. The effective dose was screened and the experiment was divided into control group and drug treatment groups. The migration ability was monitored by wound healing assay, and intracellular pH was detected by pH indicator fluorescent probe. The protein expression levels of inwardly-rectifying potassium channel 4.1 (Kir4.1) and monocarboxylate transport protein 1 (MCT1) were determined by Western blot. RESULTS: The half maximal inhibitory concentrations (IC₅₀) of Glib for 48 h exposure of U251 cells and U87 cells were 400.20 μmol/L and 553.70 μmol/L, respectively. The effective inhibition doses of Glib for U251 cells were from the ranges of 100 μmol/L to 1 600 μmol/L, and those for U87 cells were from 50 μmol/L to 1 600 μmol/L in a concentration-dependent manner (P<0.05). Glib not only inhibited the migration (P<0.05) of U251 cells and U87 cells, which was negatively correlated with drug concentration (P<0.05), but also reduced the intracellular fluorescence intensity in experimental group (P<0.05), suggesting that with the increase in drug concentration, the intracellular pH decreased gradually (P<0.05). The protein expression of Kir4.1 and MCT1 was down-regulated by treatment with Glib, and was negatively correlated with concentration of Glib. CONCLUSION: Glib, a kind of potassium channel blocker, induces intracellular acidification via down-regulating the expression of Kir4.1 and MCT1, thus inhibiting the growth of glioblastoma in a certain dose range.