ATP-induced apoptosis involves a Ca2+-independent phospholipase A2 and 5-lipoxygenase in macrophages
ATP-induced apoptosis involves a Ca2+-independent phospholipase A2 and 5-lipoxygenase in macrophages
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DOI：
10.1016/j.prostaglandins.2008.09.004
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发表时间：
2009-01-01
影响因子：
2.9
通讯作者：
Persechini, Pedro Muanis
中科院分区：
文献类型：
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作者：
Costa-Junior, Helio Miranda;Mendes, Anderson Nogueira;Persechini, Pedro Muanis
巨噬细胞表达P2X(7)和其他核苷酸（P2）受体，并表现出细胞外ATP（ATP(e)）诱导的P2X(7)依赖的膜渗透和细胞凋亡和坏死的现象。P2X7受体还与toll样受体（TLRs）协同诱导炎性小体活化和IL-1 β分泌。我们在小鼠腹腔巨噬细胞中研究了ATP诱导细胞死亡的信号通路。在ATP存在的情况下，诱导20 min后6 h细胞凋亡（次二倍体细胞核）和坏死（LDH释放）发生。凋亡被caspase 3、caspase 9抑制剂和环孢素a阻断。MAPK抑制剂PD-98059、SB-203580和SB-202190对细胞凋亡无显著影响，但SB-203580抑制LDH释放。在诱导期内，细胞内和细胞外Ca2+均被螯合，细胞凋亡和坏死均未受到抑制。Mepacrine，一种通用的PLA(2)抑制剂和BEL，一种Ca2+非依赖性PLA(2)抑制剂（iPLA(2)）阻断细胞凋亡，而pBPB和AACOOPF(3)。分泌抑制剂和Ca2+依赖性PLA(2)分别对其无显著影响。环氧合酶抑制剂对细胞凋亡无影响，而脂氧合酶（LOX）和白三烯生物合成抑制剂去二氢愈创木酸（NDGA）、zileuton、AA-861和MK-886显著降低细胞凋亡。NDGA和MK-886均未阻断5-LOX-/-巨噬细胞的凋亡。白三烯受体拮抗剂CP-105696和MK-571对细胞凋亡无显著影响。PLA(2)和LOX/白三烯途径抑制剂对LDH释放均无明显抑制作用。我们的研究结果表明，涉及iPLA(2)和5-LOX的Ca2+独立步骤参与了巨噬细胞中P2X7触发的凋亡而不是坏死。(C) 2008爱思唯尔公司版权所有。
Macrophages express P2X(7) and other nucleotide (P2) receptors, and display the phenomena of extracellular ATP (ATP(e))-induced P2X(7)-dependent membrane permeabilization and cell death by apoptosis and necrosis. P2X7 receptors also cooperate with toll-like receptors (TLRs) to induce inflammasome activation and IL-1 beta secretion. We investigated signaling pathways involved in the induction of cell death by ATP, in intraperitoneal murine macrophages. Apoptosis (hypodiploid nuclei) and necrosis (LDH release) were detected 6 h after an induction period of 20 min in the presence of ATP Apoptosis was blocked by caspase 3 and caspase 9 inhibitors and by cyclosporin A. The MAPK inhibitors PD-98059, SB-203580 and SB-202190 provoked no significant effect oil apoptosis, but SB-203580 blocked LDH release. Neither apoptosis nor necrosis was inhibited when both intra- and extracellular Ca2+ were chelated during the induction period. Mepacrine, a generic PLA(2) inhibitor and BEL, an inhibitor of Ca2+-independent PLA(2) (iPLA(2)) blocked apoptosis, while pBPB and AACOOPF(3). inhibitors of secretory and Ca2+-dependent PLA(2) respectively, had no significant effect. Cycloxygenase inhibitors had no effect on apoptosis, while the inhibitors of lipoxygenase (LOX) and leukotriene biosynthesis nordihydroguaiaretic acid (NDGA), zileuton, AA-861, and MK-886 significantly decreased apoptosis. Neither NDGA nor MK-886 blocked apoptosis of 5-LOX-/- macrophages. CP-105696 and MK-571, antagonists of leukotriene receptors, had no significant effect on apoptosis. None of the inhibitors of PLA(2) and LOX/leukotriene pathway had a significant inhibitory effect on LDH release. Our results indicate that a Ca2+ -independent step involving an iPLA(2) and 5-LOX are involved in the triggering of apoptosis but not necrosis by P2X7 in macrophages. (C) 2008 Elsevier Inc. All rights reserved.