目的观测自行研制的脂氧化酶抑制剂诺帝(Nordy)对人恶性胶质瘤细胞系U87中甲酰化肽受体(FPR)的表达和激活后功能活性的影响。方法采用间接免疫荧光标记、激光共聚焦扫描显微术观测诺帝对U87系人恶性胶质瘤细胞FPR表达的影响;FPR激动剂N-甲酰化的甲硫酰-亮氨酸-苯丙氨酰胺(fMLF)激活FPR后加入诺帝,实验分为以下3组:①对照组,②fMLF刺激组,③诺帝处理组,分别采用四甲基偶氮唑盐(MTT)法、逆转录聚合酶链式反应(RT—PCR)和双抗夹心酶联免疫吸附法(ELISA)检测诺帝对FPR活化后引起的细胞增殖及细胞分泌血管内皮生长因子(VEGF)和白细胞介素8(IL-8)的作用。结果诺帝(100μmol/L)明显抑制U87细胞FPR受体的表达,同时对FPR激动剂fMLF(100nmol/L)诱导的U87细胞增殖和血管生成因子VEGF、IL-8 mRNA表达和蛋白的分泌具有明显的抑制作用。对照组U87细胞分泌一定量的VEGF和IL-8,分别为(4.14±0.28)ng/ml和(4.03±0.59)ng/ml;fMLF作用于U87细胞36h后,VEGF和IL-8蛋白水平均显著高于对照组(P〈0.05),分别为(6.46±0.33)ng/ml和(7.54±0.73)ng/ml;诺帝作用于U87细胞12h后加入fMLF共同处理36h后,VEGF和IL-8蛋白水平分别为(3.59±0.33)ng/ml和(3.13±0.48)ng/ml,均显著低于对照组(P〈0.05)。结论诺帝对人恶性胶质瘤细胞的FPR表达和该受体活化后的促瘤细胞增殖及促血管生成因子VEGF、IL-8 mRNA表达和蛋白的分泌具有抑制作用,提示诺帝具有抑制肿瘤生长和抗血管生成的作用。
Objective To explore the effect of Nordy, a synthesized lipoxygenase Inhibitor, on the expression of formylpeptide receptor (FPR) and its functional activities after activation in human malignant glioma cells. Methods Human malignant glioma cells of the line U87 were cultured and divided into 3 groups: N-formyl-methionyl-leucyl-phenyalanine (fMLF) group, added with 100 nmol/L fMLF; Nordy group, added with 100 μmol/L Nordy for 12 h and then added with 100 nmol/L fMLF; and control group. The expression of FPR I the U87 cells was detected with indirect immunofluorescene staining and confocal laser scanning microscopy. The effect of Nordy on the U87 cell proliferation induced by fMLF was assayed by MTT method. RT-PCR was used to detect the mRNA expression of vascular endothelial growth factor (VEGF) and interleukin-8 (IL-8) in the U87 cells. ELISA was used to detect protein secretion of VEGF and IL-8 in the supernatant. Results FPR was expressed on the cytoplasmic membrane of U87 cells. The mean FPR absorbance of the Nordy group was significantly lower than that of the fMLF group. The U87 cell proliferation of the Nordy group was significantly inhibited in comparison with the other 2 groups. The mRNA expression of VEGF and mRNA expression of IL-8 in the U87 cells activated by fMLF were significantly higher than those of the control group ( both P 〈 0. 05 ) , and Nordy significantly attenuated the mRNA expression of VEGF and IL-8 at different time points ( all P 〈 0.05 ). ELISA showed that the VEGF and IL- 8 protein levels in the supernatant were 4. 14 ng/ml ± 0. 28 ng/ml and 4.03 ng/ml ± 0. 59 ng/ml respectively, and increased to 6.46 ng/ml ± 0.33 ng/ml and 7.54 ng/ml ± 0.73 ng/ml respectively after stimulation of fMLF, however, the VEGF and IL-8 protein levels in the supernatant of the Nordy group were 3.59 ng/ml ± 0.33 ng/ml and 3.13 ng/ml ± 0.48 ng/ml respectively. Conclusion Nordy inhibits the FPR expression and the effects in promoting the cell proliferation and mRNA expressi