RIP1 and RIP3 contribute to shikonin-induced glycolysis suppression in glioma cells via increase of intracellular hydrogen peroxide

• Published in: Cancer letters 2018-07, Vol.425, p.31-42
• Main Authors: Lu, Bin, Wang, Zongqi, Ding, Ye, Wang, Xuanzhong, Lu, Shan, Wang, Chongcheng, He, Chuan, Piao, Meihua, Chi, Guangfan, Luo, Yinan, Ge, Pengfei
• Format: Article
• Language: English
• Subjects: Accumulation; Apoptosis; Brain cancer; Cell death; Cysteine; Dehydrogenases; Depletion; Flow cytometry; Glioma; Glioma cells; Glycolysis; Hydrogen peroxide; Initiators; Intracellular; Kinases; Laboratory animals; Medical prognosis; Necroptosis; Proteins; Pyruvic acid; RIP1; RIP3; Shikonin; siRNA
• ISSN: 0304-3835; 1872-7980
• DOI: 10.1016/j.canlet.2018.03.046

RIP1 and RIP3 are necroptosis initiators, but their roles in regulation of glycolysis remain elusive. In this study, we found shikonin activated RIP1 and RIP3 in glioma cells in vitro and in vivo, which was accompanied with glycolysis suppression. Further investigation revealed that shikonin-induced decreases of glucose-6-phosphate and pyruvate and downregulation of HK II and PKM2 were significantly prevented when RIP1 or RIP3 was pharmacologically inhibited or genetically knocked down with SiRNA. Moreover, shikonin also triggered accumulation of intracellular H2O2 and depletion of GSH and cysteine. Mitigation of intracellular H2O2 via supplement of GSH reversed shikonin-induced glycolysis suppression. The role of intracellular H2O2 in regulation of glycolysis suppression was further confirmed in the cells treated with exogenous H2O2. Notably, inhibition of RIP1 or RIP3 prevented intracellular H2O2 accumulation, which was correlated with preventing shikonin-induced downregulation of x-CT and depletion of GSH and cysteine. In addition, supplement of pyruvate effectively inhibited shikonin- or exogenous H2O2-induced accumulation of intracellular H2O2 and glioma cell death. Taken together, we demonstrated in this study that RIP1 and RIP3 contributed to shikonin-induced glycolysis suppression via increasing intracellular H2O2. •Shikonin activates RIP1 and RIP3 but inhibits glycolysis and in glioma cells in vitro and in vivo.•RIP1 and RIP3 contribute to shikonin-induced glycolysis suppression.•H2O2 participates in the regulation of shikonin-induced glycolysis suppression in glioma cells.•RIP1 and RIP3 improve shikonin-induced accumulation of H2O2 via causing GSH depletion.•Pyruvate depletion promotes shikonin-induced accumulation of H2O2 and cell death.