Yin Cheng, Huang Guang-Fu, Sun Xiao-Chuan, Guo Zongduo, Zhang John H
Departments of Anesthesiology and Physiology, Loma Linda University School of Medicine, Loma Linda, CA, USA; Department of Neurosurgery, Hospital of the University of Electronic Science and Technology of China, Sichuan Provincial People's Hospital, Chengdu, China.
Department of Neurosurgery, Hospital of the University of Electronic Science and Technology of China, Sichuan Provincial People's Hospital, Chengdu, China.
Neuropharmacology. 2016 Sep;108:316-23. doi: 10.1016/j.neuropharm.2016.04.013. Epub 2016 Apr 13.
Since tozasertib is neuroprotective for injured optic nerve, this study is intended to test whether tozasertib reduces early brain injury after subarachnoid hemorrhage (SAH) in a rat model.
Two hundred sixteen (216) male Sprague-Dawley rats were randomly subjected to endovascular perforation model of SAH and sham group. SAH grade, neurological score, and brain water content were measured at 24 and 72 h after SAH. Dual leucine zipper kinase (DLK) and its downstream factors, JNK-interacting protein 3 (JIP3), MA2K7, p-JNK/JNK (c-Jun N-terminal kinase), and apoptosis related proteins cleaved caspase-3 (CC-3), Bim, Bcl-2, and cleaved caspase-9 (CC-9) were analyzed by western blot at 24 h after SAH. Apoptotic cells were detected by terminal deoxynucleotid transferase-deoxyuridine triphosphate (dUTP) nick end labeling (TUNEL). DLK small interfering RNA (siRNA), JIP3 siRNA and MA2K7 siRNA, the JNK, p38MAPK, and MEK inhibitors SP600125, SB203580, and PD98059 were used for intervention.
Tozasertib reduced neuronal apoptosis, attenuated brain edema and improved neurobehavioral deficits 24 and 72 h after SAH. At 24 h After SAH, DLK/JIP3/MA2K7/p-JNK/CC-3 expressions were elevated markedly and tozasertib reduced DLK, MA2K7/p-JNK/CC-3 expressions but enhanced JIP3 expression. In the presence of tozasertib, DLK/JIP3/MA2K7 siRNA and SP600125, SB203580 and PD98059 deteriorated the neurobehavioral deficits, brain edema and increased the expression of CC-3. SAH potentiated the expression of Bim, CC-9, and CC-3 but reduced Bcl-2, while tozasertib reduced expression of Bim, CC-9, and CC-3 but enhanced Bcl-2.
Tozasertib reduced neuronal apoptosis and improved outcome possibly via DLK/JIP3/MA2K7/JNK pathways after SAH.
由于托扎司他对损伤的视神经具有神经保护作用，本研究旨在测试托扎司他是否能减轻大鼠蛛网膜下腔出血（SAH）后的早期脑损伤。
将216只雄性Sprague-Dawley大鼠随机分为SAH血管内穿刺模型组和假手术组。在SAH后24小时和72小时测量SAH分级、神经功能评分和脑含水量。在SAH后24小时通过蛋白质免疫印迹法分析双亮氨酸拉链激酶（DLK）及其下游因子，即JNK相互作用蛋白3（JIP3）、MA2K7、磷酸化JNK/JNK（c-Jun氨基末端激酶）以及凋亡相关蛋白裂解的半胱天冬酶-3（CC-3）、Bim、Bcl-2和裂解的半胱天冬酶-9（CC-9）。通过末端脱氧核苷酸转移酶介导的dUTP缺口末端标记法（TUNEL）检测凋亡细胞。使用DLK小干扰RNA（siRNA）、JIP3 siRNA和MA2K7 siRNA以及JNK、p38丝裂原活化蛋白激酶（MAPK）和MEK抑制剂SP600125、SB203580和PD98059进行干预。
托扎司他减少了SAH后24小时和72小时的神经元凋亡，减轻了脑水肿，并改善了神经行为缺陷。SAH后24小时，DLK/JIP3/MA2K7/磷酸化JNK/CC-3的表达显著升高，托扎司他降低了DLK、MA2K7/磷酸化JNK/CC-3的表达，但增强了JIP3的表达。在存在托扎司他的情况下，DLK/JIP3/MA2K7 siRNA以及SP600125、SB203580和PD98059使神经行为缺陷和脑水肿恶化，并增加了CC-3的表达。SAH增强了Bim、CC-9和CC-3的表达，但降低了Bcl-2的表达，而托扎司他降低了Bim、CC-9和CC-3的表达，但增强了Bcl-2的表达。
托扎司他可能通过SAH后的DLK/JIP3/MA2K7/JNK途径减少神经元凋亡并改善预后。
