PDF(Pubmed)
Abstract：
BACKGROUND: Previously, we have reported on the two curcuminoid analogues with piperidone derivatives, namely FLDP-5 and FLDP-8 have more potent anti-proliferative and anti-migration effects than curcumin. In this study, we further investigated the mode of cell death and the mechanism involved in the cell death process induced by these analogues on human glioblastoma LN-18 cells.
RESULTS: The FLDP-5 and FLDP-8 curcuminoid analogues induced LN-18 cell death through apoptosis in a concentration-dependent manner following 24 h of treatment. These analogues induced apoptosis in LN-18 cells through significant loss of mitochondrial mass and mitochondrial membrane potential (MMP) as early as 1-hour of treatment. Interestingly, N-acetyl-l-cysteine (NAC) pretreatment did not abolish the apoptosis induced by these analogues, further confirming the cell death process is independent of ROS. However, the apoptosis induced by the analogues is caspases-dependent, whereby pan-caspase pretreatment inhibited the curcuminoid analogues-induced apoptosis. The apoptotic cell death progressed with the activation of both caspase-8 and caspase-9, which eventually led to the activation of caspase-3, as confirmed by immunoblotting. Moreover, the existing over-expression of miRNA-21 in LN-18 cells was suppressed following treatment with both analogues, which suggested the down-regulation of the miRNA-21 facilitates the cell death process.
CONCLUSIONS: The FLDP-5 and FLDP-8 curcuminoid analogues downregulate the miRNA-21 expression and induce extrinsic and intrinsic apoptotic pathways in LN-18 cells.
RESULTS: The FLDP-5 and FLDP-8 curcuminoid analogues induced LN-18 cell death through apoptosis in a concentration-dependent manner following 24 h of treatment. These analogues induced apoptosis in LN-18 cells through significant loss of mitochondrial mass and mitochondrial membrane potential (MMP) as early as 1-hour of treatment. Interestingly, N-acetyl-l-cysteine (NAC) pretreatment did not abolish the apoptosis induced by these analogues, further confirming the cell death process is independent of ROS. However, the apoptosis induced by the analogues is caspases-dependent, whereby pan-caspase pretreatment inhibited the curcuminoid analogues-induced apoptosis. The apoptotic cell death progressed with the activation of both caspase-8 and caspase-9, which eventually led to the activation of caspase-3, as confirmed by immunoblotting. Moreover, the existing over-expression of miRNA-21 in LN-18 cells was suppressed following treatment with both analogues, which suggested the down-regulation of the miRNA-21 facilitates the cell death process.
CONCLUSIONS: The FLDP-5 and FLDP-8 curcuminoid analogues downregulate the miRNA-21 expression and induce extrinsic and intrinsic apoptotic pathways in LN-18 cells.
摘要：
背景：以前，我们已经报道了两种姜黄素类似物与哌啶酮衍生物，即FLDP-5和FLDP-8比姜黄素具有更有效的抗增殖和抗迁移作用。在这项研究中,我们进一步研究了这些类似物对人胶质母细胞瘤LN-18细胞诱导的细胞死亡方式和机制。
结果：处理24小时后，FLDP-5和FLDP-8类姜黄素类似物通过凋亡以浓度依赖性方式诱导LN-18细胞死亡。这些类似物在LN-18细胞中通过早在治疗1小时时线粒体质量和线粒体膜电位(MMP)的显著损失而诱导凋亡。有趣的是,N-乙酰-1-半胱氨酸（NAC）预处理并没有消除这些类似物诱导的细胞凋亡，进一步证实细胞死亡过程独立于ROS。然而,由类似物诱导的细胞凋亡是依赖caspases的，其中pan-caspase预处理抑制姜黄素类似物诱导的细胞凋亡。凋亡性细胞死亡随着caspase-8和caspase-9的激活而进行,这最终导致caspase-3的激活,如通过免疫印迹所证实的。此外，用两种类似物处理后，LN-18细胞中miRNA-21的现有过表达受到抑制，这表明miRNA-21的下调促进了细胞死亡过程。
结论：FLDP-5和FLDP-8类姜黄素类似物在LN-18细胞中下调miRNA-21表达并诱导外在和内在凋亡途径。
结果：处理24小时后，FLDP-5和FLDP-8类姜黄素类似物通过凋亡以浓度依赖性方式诱导LN-18细胞死亡。这些类似物在LN-18细胞中通过早在治疗1小时时线粒体质量和线粒体膜电位(MMP)的显著损失而诱导凋亡。有趣的是,N-乙酰-1-半胱氨酸（NAC）预处理并没有消除这些类似物诱导的细胞凋亡，进一步证实细胞死亡过程独立于ROS。然而,由类似物诱导的细胞凋亡是依赖caspases的，其中pan-caspase预处理抑制姜黄素类似物诱导的细胞凋亡。凋亡性细胞死亡随着caspase-8和caspase-9的激活而进行,这最终导致caspase-3的激活,如通过免疫印迹所证实的。此外，用两种类似物处理后，LN-18细胞中miRNA-21的现有过表达受到抑制，这表明miRNA-21的下调促进了细胞死亡过程。
结论：FLDP-5和FLDP-8类姜黄素类似物在LN-18细胞中下调miRNA-21表达并诱导外在和内在凋亡途径。
