Activation of microglial cells via protease-activated receptor 2 mediates neuronal cell death in cultured rat primary neuron
Activation of microglial cells via protease-activated receptor 2 mediates neuronal cell death in cultured rat primary neuron
复制标题
DOI：
10.1016/j.niox.2009.10.008
复制
发表时间：
2010-01-01
影响因子：
3.9
通讯作者：
Ko, Kwang Ho
中科院分区：
文献类型：
--
作者：
Park, Gyu Hwan;Jeon, Se Jin;Ko, Kwang Ho
蛋白酶激活受体（PARs）在小胶质细胞活化过程中的调节作用日益明显。在本研究中，我们研究了FAR-2的作用，它可以被胰蛋白酶样蛋白酶激活，在小胶质细胞活化和神经元细胞死亡。在培养的大鼠原代小胶质细胞中。PAR-2通过PKC和MAPK依赖性机制诱导的亚硝酸盐产生的激活。在MAPK通路的三个成员中，ERK和JNK而不是p38介导PAR-2诱导的小胶质细胞活化。NF-κ B B通路是PAR-2-PKC-MAPK通路诱导小胶质细胞活化的下游调节因子。除了亚硝酸盐，PAR-2激活增加了多种炎症介质的产生，如ROS和促炎细胞因子，包括TNF-α和IL-1 β。加入来自PAR-2激活的小胶质细胞的培养用过的培养基诱导原代大鼠皮层神经元培养物中的神经元细胞死亡，其具有凋亡特征，例如末端脱氧核苷酸转移酶介导的dUTP缺口末端标记阳性神经元的数量增加，线粒体膜电位的耗散，促凋亡Bax的表达增加，抗凋亡Bcl-2，Bcl-X-L，和神经元中caspase-3的激活。有趣的是，细胞活性分子的产生增加以及神经元细胞死亡被PAR-2或胰蛋白酶抑制剂或NO合酶抑制剂N-G-硝基-L-精氨酸甲酯正常化。总之，这些结果表明，明显的PAR-2激活可能会诱导小胶质细胞激活，这有助于神经元细胞死亡。(C)2009 Elsevier Inc. All rights reserved.
The role of protease-activated receptor (PARs) in the regulation of microglial activation process is increasingly evident. In the present study, we have investigated the role of FAR-2, which can be activated by trypsin-like proteases, in microglial activation and neuronal cell death. in cultured rat primary microglia. activation of PAR-2 induced nitrite production by PKC- and MAPKs-dependent mechanism. Among the three members of MAPK pathway, ERK and JNK but not p38 mediated PAR-2-induced microglial activation. The down-stream regulator of PAR-2-PKC-MAPK pathway-induced microglial activation was NF-kappa B pathway. Besides nitrite, PAR-2 activation increased production of a variety of inflammatory mediators such as ROS and pro-inflammatory cytokines including TNF-alpha and IL-1 beta. The addition of culture spent media from PAR-2 activated microglia induced neuronal cell death in primary rat cortical neuron cultures with apoptotic features such as increased number of terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling-positive neurons, dissipation of mitochondrial membrane potential, increased expression of pro-apoptotic Bax, decreased expression of anti-apoptotic Bcl-2, Bcl-X-L, and activation of caspase-3 in neurons. Interestingly, the increased production of cytoactive molecules as well as the neuronal cell death was normalized by PAR-2 or trypsin inhibitor or an NO synthase inhibitor, N-G-nitro-L-arginine-methyl ester. Taken together, these results suggest that overt PAR-2 activation may induce microglial activation, which contributes to neuronal cell death. (C) 2009 Elsevier Inc. All rights reserved.