Department of Pediatrics, Division of Neonatology, Children's National Medical Center, The George Washington University, School of Medicine and Health Sciences, Washington, DC, USA.
Department of Pediatrics, Drexel University College of Medicine, Philadelphia, PA, USA.
Sci Rep. 2017 Nov 30;7(1):16664. doi: 10.1038/s41598-017-16983-1.
We have previously shown that cerebral Hypoxia-ischemia (HI) results in activation of Src kinase in the newborn piglet brain. We investigated the regulatory mechanism by which the pre-apoptotic proteins translocate from mitochondria to the cytosol during HI through the Src kinase. Newborn piglets were divided into 3 groups (n = 5/group): normoxic (Nx), HI and HI pre-treated with Src kinase inhibitor PP2 (PP2 + HI). Brain tissue HI was verified by neuropathological analysis and by Adenosine Triphosphate (ATP) and Phosphocreatine (PCr) levels. We used western blots, immunohistochemistry, H&E and biochemical enzyme assays to determine the role of Src kinase on mitochondrial membrane apoptotic protein trafficking. HI resulted in decreased ATP and PCr levels, neuropathological changes and increased levels of cytochrome c, Smac/DIABLO and AIF in the cytosol while their levels were decreased in mitochondria compared to Nx. PP2 decreased the cytosolic levels of pre-apoptotic proteins, attenuated the neuropathological changes and apoptosis and decreased the HI-induced increased activity of caspase-3. Our data suggest that Src kinase may represent a potential target that could interrupt the enzymatic activation of the caspase dependent cell death pathway.
我们之前已经表明，脑缺氧缺血（HI）会导致新生仔猪大脑中的Src 激酶激活。我们通过 Src 激酶研究了前凋亡蛋白在 HI 期间从线粒体易位到细胞质的调节机制。新生仔猪分为 3 组（每组 n=5）：常氧（Nx）、HI 和 HI 预先用 Src 激酶抑制剂 PP2 处理（PP2+HI）。通过神经病理学分析和三磷酸腺苷（ATP）和磷酸肌酸（PCr）水平验证脑组织 HI。我们使用 Western blot、免疫组织化学、H&E 和生化酶测定来确定 Src 激酶在线粒体膜凋亡蛋白转运中的作用。与 Nx 相比，HI 导致 ATP 和 PCr 水平降低、神经病理学变化以及细胞浆中细胞色素 c、Smac/DIABLO 和 AIF 水平升高，而线粒体中这些蛋白的水平降低。PP2 降低了细胞浆中前凋亡蛋白的水平，减轻了神经病理学变化和细胞凋亡，并降低了 HI 诱导的 caspase-3 活性增加。我们的数据表明，Src 激酶可能代表一个潜在的靶点，可以中断半胱氨酸天冬氨酸蛋白酶依赖性细胞死亡途径的酶激活。
