Department of Biotechnology and Animal Science, National Ilan University, 1 Sec. 1 Shen-Lung Road, Ilan, Taiwan.
Inflamm Res. 2013 Jan;62(1):89-96. doi: 10.1007/s00011-012-0555-2. Epub 2012 Sep 18.
Reactive oxygen species (ROS) plays a critical role in the regulation of NLRP3 inflammasome activation. However, the ROS-mediated signaling pathways controlling NLRP3 inflammasome activation are not well defined.
Using lipopolysaccharide (LPS) and adenosine triphosphate (ATP) activated murine macrophages as the testing model, cytokine release and protein expression were quantified by enzyme-linked immunosorbent assay and Western blot, respectively. ROS was scavenged by N-acetyl cysteine; NADPH oxidase, the major source of ROS, was inhibited by diphenyliodonium, apocynin or gp91-phox siRNA transfection; and protein kinase was inhibited by its specific inhibitor.
LPS-induced NLRP3 protein expression was regulated through the NADPH oxidase/ROS/NF-κB-dependent, JAK2/PI3-kinase/AKT/NF-κB-dependent, and MAPK-dependent pathways, while ATP-induced caspase-1 activation was regulated through the NADPH oxidase/ROS-dependent pathway.
These results demonstrate that ROS regulates not only the priming stage, but also the activation stage, of NLRP3 inflammasome activation in LPS + ATP-activated macrophages.
活性氧（ROS）在调控 NLRP3 炎性小体激活中起着关键作用。然而，ROS 介导的信号通路调控 NLRP3 炎性小体激活的机制尚不完全清楚。
利用脂多糖（LPS）和三磷酸腺苷（ATP）激活的小鼠巨噬细胞作为检测模型，通过酶联免疫吸附试验和 Western blot 分别定量细胞因子释放和蛋白表达。通过 N-乙酰半胱氨酸清除 ROS；通过二苯基碘鎓、白藜芦醇或 gp91-phox siRNA 转染抑制 NADPH 氧化酶，ROS 的主要来源；通过其特异性抑制剂抑制蛋白激酶。
LPS 诱导的 NLRP3 蛋白表达受 NADPH 氧化酶/ROS/NF-κB 依赖性、JAK2/PI3-激酶/AKT/NF-κB 依赖性和 MAPK 依赖性通路调控，而 ATP 诱导的半胱天冬酶-1 激活受 NADPH 氧化酶/ROS 依赖性通路调控。
这些结果表明，ROS 不仅调控 LPS+ATP 激活的巨噬细胞中 NLRP3 炎性小体激活的初始阶段，也调控其激活阶段。
