Mu opioid receptor-mediated release of endolysosome iron increases levels of mitochondrial iron, reactive oxygen species, and cell death.
Mu opioid receptor-mediated release of endolysosome iron increases levels of mitochondrial iron, reactive oxygen species, and cell death.
复制标题
DOI：
10.1515/nipt-2022-0013
复制
发表时间：
2023-03-25
期刊：
影响因子：
--
通讯作者：
中科院分区：
文献类型：
--
作者：
吗啡和DAMGO等阿片样物质可激活mu-阿片样受体（MOR），增加细胞内活性氧（ROS）水平，诱导细胞死亡。铁（Fe2+）通过类芬顿化学增加ROS水平，而内溶酶体是“铁代谢的主要调节剂”，含有易释放的Fe2+储存。然而，阿片诱导的内溶酶体铁稳态变化和下游信号事件的机制尚不清楚。我们使用SH-SY5Y神经母细胞瘤细胞、流式细胞术和共聚焦显微镜检测Fe2+和ROS水平和细胞死亡。吗啡和DAMGO使内溶酶体脱酸，降低内溶酶体Fe2+水平，增加细胞质和线粒体Fe2+和ROS水平，使线粒体膜电位去极化，诱导细胞死亡；非选择性MOR拮抗剂纳洛酮和选择性MOR拮抗剂β-富纳曲胺（β-FNA）阻断的作用。去铁胺，一种内溶酶体铁螯合剂，抑制阿片激动剂诱导的细胞质和线粒体Fe2+和ROS的增加。阿片诱导的内溶酶体Fe2+外排和随后的Fe2+在线粒体中的积累被内溶酶体驻留双孔通道抑制剂NED-19和线粒体通透性过渡孔抑制剂TRO阻断。阿片激动剂诱导的细胞质和线粒体Fe2+和ROS的增加以及细胞死亡出现在内溶酶体去酸化和Fe2+从内溶酶体铁池流出的下游，这足以影响其他细胞器。
Opioids including morphine and DAMGO activate mu-opioid receptors (MOR), increase intracellular reactive oxygen species (ROS) levels, and induce cell death. Ferrous iron (Fe2+) through Fenton-like chemistry increases ROS levels and endolysosomes are “master regulators of iron metabolism” and contain readily-releasable Fe2+ stores. However, mechanisms underlying opioid-induced changes in endolysosome iron homeostasis and downstream-signaling events remain unclear. We used SH-SY5Y neuroblastoma cells, flow cytometry, and confocal microscopy to measure Fe2+ and ROS levels and cell death. Morphine and DAMGO de-acidified endolysosomes, decreased endolysosome Fe2+ levels, increased cytosol and mitochondria Fe2+ and ROS levels, depolarized mitochondrial membrane potential, and induced cell death; effects blocked by the nonselective MOR antagonist naloxone and the selective MOR antagonist β-funaltrexamine (β-FNA). Deferoxamine, an endolysosome-iron chelator, inhibited opioid agonist-induced increases in cytosolic and mitochondrial Fe2+ and ROS. Opioid-induced efflux of endolysosome Fe2+ and subsequent Fe2+ accumulation in mitochondria were blocked by the endolysosome-resident two-pore channel inhibitor NED-19 and the mitochondrial permeability transition pore inhibitor TRO. Opioid agonist-induced increases in cytosolic and mitochondrial Fe2+ and ROS as well as cell death appear downstream of endolysosome de-acidification and Fe2+ efflux from the endolysosome iron pool that is sufficient to affect other organelles.