常氧和低氧条件下肌肽对脑胶质瘤细胞增殖的作用及其机制  

The effect and mechanism of carnosine on glioma cell proliferation under normoxic and hypoxic conditions

作　　者：段荣清 厉柳岑 汤旗 梅蕾 沈耀[1] DUAN Rongqing;LI Liucen;TANG Qi;MEI Lei;SHEN Yao(School of Laboratory Medicine and Life Sciences,Wenzhou Medical University,Wenzhou 325035,China)

机构地区：[1]温州医科大学检验医学院(生命科学学院),浙江温州325035

出　　处：《温州医科大学学报》2023年第7期540-547,共8页Journal of Wenzhou Medical University

基　　金：浙江省自然科学基金项目(LY19H090010);温州医科大学基本科研业务项目(KYYW201903)。

摘　　要：目的:研究肌肽对脑胶质瘤细胞增殖的影响并探讨其作用机制。方法:将细胞样本分为常氧组、常氧+肌肽组、低氧组、低氧+肌肽组,在常氧(21%O2)和低氧(1%O2)处理下分别用25 mmol/L和50 mmol/L肌肽处理U251和U87细胞,采用MTT法检测胶质瘤细胞增殖的变化情况;采用克隆形成实验检测胶质瘤细胞克隆形成能力的变化;采用Annexin V-FITC/PI凋亡检测试剂盒和流式细胞术检测胶质瘤细胞凋亡;运用非靶向代谢组学分析胶质瘤的代谢变化;采用LC-MS法检测胶质瘤细胞蛋氨酸含量变化;采用Western blot法检测c-Myc和LAT1蛋白表达水平;采用RT-q PCR法测定c-Myc和LAT1 mRNA水平。结果:在常氧和低氧条件下,肌肽可以显著抑制胶质瘤细胞的增殖和克隆形成能力(P<0.05)。肌肽可以促进胶质瘤细胞的凋亡(P<0.05)。肌肽对U251细胞的氨基酸代谢产生影响,使赖氨酸、蛋氨酸、精氨酸的含量下调(P<0.05)。肌肽处理U251细胞后c-Myc和LAT1表达均下调(P<0.05)。结论:在常氧和低氧条件下,肌肽可以抑制胶质瘤细胞的增殖并诱导其凋亡,这种作用可能是通过抑制c-Myc/LAT1轴来实现的。Objective:To study the effect of carnosine on the proliferation of glioma cells and to explore its mechanism.Methods:Cell samples were divided into normoxia group(21%O2),normoxia carnosine group,hypoxia group(1%O2),hypoxia carnosine group.Under normal oxygen and hypoxia treatment,U251 and U87 cells were treated with 25 mmol/L and 50 mmol/L carnosine,and the changes of glioma cell proliferation were detected by MTT method.The clonal formation experiment was used to detect the change of clonal formation ability of glioma cells.Annexin V-FITC/PI apoptosis was detected by Annexin V-FITC/PI apoptosis assay kit and flow cytometry.Non-targeted metabolomics was used to analyze the metabolic changes of gliomas;LC-MS method was used to detect the change of methionine content in glioma cells.The Western blot method was used to detect the expression levels of c-Myc and LAT1 proteins.C-Myc and LAT1 mRNA levels were determined by RT-qPCR.Results:After carnosine treatment,carnosine can significantly inhibit the proliferation and clonal formation ability of glioma cells under normal oxygen and hypoxic conditions(P<0.05).Carnosine can promote apoptosis in glioma cells(P<0.05).Carnosine had an effect on the amino acid metabolism of U251 cells,which reduced the content of lysine,methionine and arginine(P<0.05).After carnosine treatment of U251 cells,both c-Myc and LAT1 expression were downregulated(P<0.05).Conclusion:Under normoxic and hypoxic conditions,carnosine can inhibit the proliferation of glioma cells and induce their apoptosis,which may be achieved by inhibiting the c-Myc/LAT1 axis.

关 键 词：肌肽 脑胶质瘤 细胞增殖 C-MYC L型氨基酸转运蛋白1 

分 类 号：R739.4[医药卫生—肿瘤]