Activation of microglia with zymosan promotes excitatory amino acid release via volume-regulated anion channels: the role of NADPH oxidases.
Activation of microglia with zymosan promotes excitatory amino acid release via volume-regulated anion channels: the role of NADPH oxidases.
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DOI：
10.1111/j.1471-4159.2008.05553.x
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发表时间：
2008-09
影响因子：
4.7
通讯作者：
Mongin AA
中科院分区：
文献类型：
--
作者：
Harrigan TJ;Abdullaev IF;Jourd'heuil D;Mongin AA
小胶质细胞是中枢神经系统的常驻免疫细胞，对维持神经组织功能很重要，但也可能导致神经退行性变。在感染、炎症或创伤中，这些细胞的激活会导致各种有毒分子的释放，包括活性氧（ROS）和兴奋性氨基酸谷氨酸。在这项研究中，我们使用电生理方法和D-[3H]天冬氨酸（谷氨酸）释放试验来探索ros依赖的谷氨酸渗透性体积调节阴离子通道（vrac）的调节。大鼠小胶质细胞暴露于低渗介质刺激Cl -电流和D-[3H]天冬氨酸释放，这两者都被选择性VRAC阻滞剂DCPIB抑制。外源施加H2O2可显著增加肿胀激活谷氨酸释放。用zymosan刺激小胶质细胞触发内源性ROS的产生，并通过肿胀细胞中的VRAC强烈增强谷氨酸释放。活性氧清除剂MnTMPyP和NADPH氧化酶（NOX）抑制剂二苯基碘铵和硫代嘧啶减弱了zymosan的作用。然而，zymosan刺激的谷氨酸释放对其他NOX阻滞剂，罗布麻素和AEBSF不敏感。这一药理学特征指出了罗布麻素不敏感的NOX4的潜在参与。通过RT-PCR，我们证实NOX4与NOX1和NOX2一起在大鼠小胶质细胞中表达。为了检查吞噬细胞NOX2的潜在参与，我们使用蛋白激酶C （PKC）激活剂PMA刺激该异构体，或使用广谱PKC阻滞剂Gö6983抑制它。这两种药物都能通过NOX2有效调节内源性ROS的产生，但对VRAC活性没有作用。综上所述，这些数据表明阴离子通道VRAC可能有助于小胶质细胞谷氨酸的释放，其活性受源自NOX4的内源性ROS的调节。
Microglia are the resident immune cells of the CNS, which are important for preserving neural tissue functions, but may also contribute to neurodegeneration. Activation of these cells in infection, inflammation, or trauma leads to the release of various toxic molecules, including reactive oxygen species (ROS) and the excitatory amino acid glutamate. In this study we used an electrophysiological approach and a D-[3H]aspartate (glutamate) release assay to explore the ROS-dependent regulation of glutamate-permeable volume-regulated anion channels (VRACs). Exposure of rat microglia to hypoosmotic media stimulated Cl− currents and D-[3H]aspartate release, both of which were inhibited by the selective VRAC blocker DCPIB. Exogenously applied H2O2 potently increased swelling-activated glutamate release. Stimulation of microglia with zymosan triggered production of endogenous ROS and strongly enhanced glutamate release via VRAC in swollen cells. The effects of zymosan were attenuated by the ROS scavenger MnTMPyP, and by two inhibitors of NADPH oxidase (NOX) diphenyliodonium and thioridazine. However, zymosan-stimulated glutamate release was insensitive to other NOX blockers, apocynin and AEBSF. This pharmacological profile pointed to the potential involvement of apocynin-insensitive NOX4. Using RT-PCR we confirmed that NOX4 is expressed in rat microglial cells, along with NOX1 and NOX2. To check for potential involvement of phagocytic NOX2 we stimulated this isoform using protein kinase C (PKC) activator PMA, or inhibited it with the broad spectrum PKC blocker Gö6983. Both agents potently modulated endogenous ROS production by NOX2, but not VRAC activity. Taken together, these data suggest that the anion channel VRAC may contribute to microglial glutamate release, and that its activity is regulated by endogenous ROS originating from NOX4.
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DOI：
10.1085/jgp.200409040
发表时间：
2004-09
期刊：
The Journal of general physiology
影响因子：
--
作者：
Browe DM;Baumgarten CM
通讯作者：
Baumgarten CM
DOI：
10.1002/neu.480230915
发表时间：
1992-11-01
期刊：
JOURNAL OF NEUROBIOLOGY
影响因子：
--
作者：
CHOI, DW
通讯作者：
CHOI, DW
影响因子：
15.9
作者：
DECHATELET, LR;MCPHAIL, LC;MCCALL, CE
通讯作者：
MCCALL, CE
影响因子：
--
作者：
Choi, HS;Kim, JW;Kim, C
通讯作者：
Kim, C
影响因子：
3.9
作者：
Day, BJ;Fridovich, I;Crapo, JD
通讯作者：
Crapo, JD