Activation of T‐LAK‐cell‐originated protein kinase‐mediated antioxidation protects against focal cerebral ischemia–reperfusion injury
Activation of T‐LAK‐cell‐originated protein kinase‐mediated antioxidation protects against focal cerebral ischemia–reperfusion injury
复制标题
DOI：
10.1111/febs.12948
复制
发表时间：
2014-10
期刊：
影响因子：
--
通讯作者：
Haiping Zhao;Rongliang Wang;Z. Tao;Feng Yan;Li Gao;Xiangrong Liu;Ningqun Wang;Lianqiu Min;Yujie Jia;Yongmei Zhao;X. Ji;Yumin Luo
中科院分区：
文献类型：
--
作者：
Haiping Zhao;Rongliang Wang;Z. Tao;Feng Yan;Li Gao;Xiangrong Liu;Ningqun Wang;Lianqiu Min;Yujie Jia;Yongmei Zhao;X. Ji;Yumin Luo
T - LAK细胞源性蛋白激酶（TOPK）是一种类似MAPKK的激酶，对神经祖细胞增殖至关重要；然而，TOPK的功能和脑缺血再灌注损伤的分子机制尚不清楚。因此，我们研究了TOPK在实验性脑卒中中的作用。Sprague-Dawley大鼠进行短暂性大脑中动脉闭塞（tMCAO）和再灌注，MCAO开始时脑室内注射TOPK小干扰RNA （siRNA）。通过western blot检测TOPK过表达和H2O2刺激后PC12神经元细胞的抗氧化蛋白、凋亡相关蛋白和信号通路，ELISA检测过氧化产物（丙二醛和3 -硝基酪氨酸）的水平。tMCAO后大鼠皮质神经元中TOPK的磷酸化水平升高。TOPK在PC12细胞中的过表达增加了抗氧化蛋白（过氧还蛋白1和2、血红素加氧酶1和锰超氧化物歧化酶）的水平，以及总超氧化物歧化酶的活性，同时在H2O2刺激下抑制丙二醛和3 -硝基酪氨酸。过氧化氢作用下，PC12细胞中TOPK过表达可提高细胞活力，降低caspase 3和caspase 12的表达。在PC12细胞中，p-ERK水平因TOPK过表达而升高，TOPK的抗氧化保护作用通过阻断细胞外信号调节的激酶通路而被破坏。在体内MCAO后，TOPK siRNA增加了梗死体积，降低了皮层总超氧化物歧化酶活性。这些数据表明，激活TOPK通过抗氧化功能，部分通过激活细胞外信号调节的激酶途径，对局灶性脑缺血-再灌注损伤具有神经保护作用。
T‐LAK‐cell‐originated protein kinase (TOPK), a MAPKK‐like kinase, is crucial for neural progenitor cell proliferation; however, the function of TOPK and the molecular mechanism underlying cerebral ischemia–reperfusion injury remains unknown. Therefore, we investigated the role of TOPK in experimental stroke. Sprague–Dawley rats underwent transient middle cerebral artery occlusion (tMCAO) and reperfusion, and TOPK small interfering RNA (siRNA) was delivered by intracerebroventricular injection at the beginning of MCAO. After TOPK overexpression and H2O2 stimulation in PC12 neuronal cells, antioxidative proteins, apoptosis‐related proteins and signal pathways were detected by western blot analysis, the levels of the peroxidation products (malondialdehyde and 3–nitrotyrosine) were measured with ELISA. Phosphorylation of TOPK was increased in rat cortical neurons following tMCAO. TOPK overexpression in PC12 cells augmented levels of antioxidative proteins (peroxiredoxin 1 and 2, heme oxygenase 1 and manganese superoxide dismutase), as well as total superoxide dismutase activity, along with inhibition of malondialdehyde and 3–nitrotyrosine upon H2O2 stimulation. TOPK overexpression increased cell viability and reduced expression of caspase 3 and caspase 12 in PC12 cells in response to H2O2. The p–ERK level was increased by TOPK overexpression, and antioxidative protection afforded by TOPK was abolished by blocking the extracellular signal‐regulated kinase pathway in PC12 cells. TOPK siRNA increased the infarct volume and reduced total superoxide dismutase activity in the cortex in vivo after MCAO. These data reveal that activating TOPK confers neuroprotection against focal cerebral ischemia–reperfusion injury by antioxidative function, in part through activation of the extracellular signal‐regulated kinase pathway.