Hara Hirokazu, Taniguchi Miko, Kobayashi Mari, Kamiya Tetsuro, Adachi Tetsuo
Laboratory of Clinical Pharmaceutics, Gifu Pharmaceutical University, 1-25-4 Daigaku-nishi, Gifu 501-1196, Japan.
Laboratory of Clinical Pharmaceutics, Gifu Pharmaceutical University, 1-25-4 Daigaku-nishi, Gifu 501-1196, Japan.
Arch Biochem Biophys. 2015 Oct 15;584:51-60. doi: 10.1016/j.abb.2015.08.014. Epub 2015 Aug 28.
Plasma is an ionized gas consisting of ions, electrons, free radicals, neutral particles, and photons. Plasma-activated medium (PAM), which is prepared by the irradiation of cell-free medium with non-thermal atmospheric pressure plasma, induces cell death in various types of cancer cell. Since PAM contains reactive oxygen species (ROS), its anti-cancer effects are thought to be attributable to oxidative stress. Meanwhile, oxidative stress has been shown to induce the liberation of zinc (Zn(2+)) from intracellular Zn(2+) stores and to provoke Zn(2+)-dependent cell death. In this study, we thus examined whether Zn(2+) is involved in PAM-induced cell death using human neuroblastoma SH-SY5Y cells. Exposure to PAM triggered cell death in SH-SY5Y cells. The cell-permeable Zn(2+) chelator N,N,N',N'-tetrakis(2-pyridinylmethyl)-1,2-ethanediamine (TPEN) protected against PAM-induced cell death. Zn(2+) imaging using the fluorescent Zn(2+) probe FluoZin-3 revealed that PAM elicited a rise of intracellular free Zn(2+). In addition, PAM stimulated PARP-1 activation, mitochondrial ROS generation, and the depletion of intracellular NAD(+) and ATP. These findings suggest that PAM-induced PARP-1 activation causes energy supply exhaustion. Moreover, TPEN suppressed all of these events elicited by PAM. Taken together, we demonstrated here that Zn(2+) released from intracellular Zn(2+) stores serves as a key mediator of PAM-induced cell death in SH-SY5Y cells.
血浆是一种由离子、电子、自由基、中性粒子和光子组成的电离气体。通过用非热大气压等离子体照射无细胞培养基制备的等离子体活化介质（PAM）可诱导多种类型癌细胞的细胞死亡。由于PAM含有活性氧（ROS），其抗癌作用被认为归因于氧化应激。同时，氧化应激已被证明可诱导锌（Zn(2+)）从细胞内锌储存中释放，并引发锌依赖性细胞死亡。因此，在本研究中，我们使用人神经母细胞瘤SH-SY5Y细胞研究了Zn(2+)是否参与PAM诱导的细胞死亡。暴露于PAM会引发SH-SY5Y细胞的细胞死亡。细胞可渗透的锌螯合剂N,N,N',N'-四（2-吡啶甲基）-1,2-乙二胺（TPEN）可保护细胞免受PAM诱导的细胞死亡。使用荧光锌探针FluoZin-3进行的锌成像显示，PAM引起细胞内游离锌（Zn(2+)）升高。此外，PAM刺激PARP-1活化、线粒体ROS生成以及细胞内NAD(+)和ATP的消耗。这些发现表明，PAM诱导的PARP-1活化导致能量供应耗尽。此外，TPEN抑制了PAM引发的所有这些事件。综上所述，我们在此证明从细胞内锌储存中释放的Zn(2+)是PAM诱导SH-SY5Y细胞死亡的关键介质。
