Tan Shougang, Hou Xiaoqun, Mei Lin
Department of Neurosurgery, Qingdao Municipal Hospital, Qingdao, Shandong 266000, P.R. China.
Oncol Lett. 2020 Oct;20(4):122. doi: 10.3892/ol.2020.11980. Epub 2020 Aug 13.
The aim of the present study was to investigate the effect of dihydrotanshinone I (DHI) on the survival of human glioma cells and the expression levels of ferroptosis-associated proteins. Human U251 and U87 glioma cells were cultured and treated with different concentrations of DHI and/or the ferroptosis inhibitor ferrostatin-1. A Cell Counting Kit-8 assay was used to determine the cell survival rate. The cells were further analyzed to determine their 5-, 12- and 15-hydroxyeicosatetraenoic acid (HETE), lactate dehydrogenase (LDH) and malondialdehyde (MDA) levels, and reduced glutathione (GSH)/oxidized glutathione (GSSG) ratios. Western blotting was used to detect ferroptosis-associated glutathione peroxidase 4 (GPX4) and long-chain acyl-CoA synthetase 4 (ACSL-4). Changes in the mitochondrial membrane potential (MMP) were also observed using tetramethylrhodamine methyl ester staining and confocal fluorescence microscopy. The results revealed that DHI inhibited the proliferation of human glioma cells. Following treatment of the U251 and U87 cells with DHI, changes in the expression levels of ferroptosis-associated proteins were observed; the expression level of GPX4 decreased and that of ACSL-4 increased. DHI also increased the levels of LDH and MDA in the human glioma cells and reduced the GSH/GSSG ratio. The DHI-treated cells also exhibited a marked reduction in MMP. Furthermore, ferrostatin-1 blocked the DHI-induced effects in human glioma cells. From these results, it may be concluded that DHI inhibits the proliferation of human glioma cells via the induction of ferroptosis.
本研究的目的是探讨二氢丹参酮I（DHI）对人胶质瘤细胞存活及铁死亡相关蛋白表达水平的影响。培养人U251和U87胶质瘤细胞，并用不同浓度的DHI和/或铁死亡抑制剂铁抑素-1进行处理。采用细胞计数试剂盒-8法测定细胞存活率。进一步分析细胞的5-、12-和15-羟基二十碳四烯酸（HETE）、乳酸脱氢酶（LDH）和丙二醛（MDA）水平，以及还原型谷胱甘肽（GSH）/氧化型谷胱甘肽（GSSG）比值。采用蛋白质免疫印迹法检测铁死亡相关的谷胱甘肽过氧化物酶4（GPX4）和长链脂酰辅酶A合成酶4（ACSL-4）。还使用四甲基罗丹明甲酯染色和共聚焦荧光显微镜观察线粒体膜电位（MMP）的变化。结果显示，DHI抑制人胶质瘤细胞的增殖。用DHI处理U251和U87细胞后，观察到铁死亡相关蛋白表达水平的变化；GPX4表达水平降低，ACSL-4表达水平升高。DHI还增加了人胶质瘤细胞中LDH和MDA的水平，并降低了GSH/GSSG比值。经DHI处理的细胞MMP也显著降低。此外，铁抑素-1阻断了DHI对人胶质瘤细胞的诱导作用。从这些结果可以得出结论，DHI通过诱导铁死亡抑制人胶质瘤细胞的增殖。
