Morita-Fujimura Y, Fujimura M, Kawase M, Murakami K, Kim G W, Chan P H
Department of Neurosurgery, Stanford University School of Medicine, Palo Alto, California 94304, USA.
J Cereb Blood Flow Metab. 1999 Jun;19(6):634-42. doi: 10.1097/00004647-199906000-00006.
The authors examined the effect of z-VAD.FMK, an inhibitor that blocks caspase family proteases, on cold injury-induced brain trauma, in which apoptosis as well as necrosis is assumed to play a role. A vehicle alone or with z-VAD.FMK was administered into the cerebral ventricles of mice 15 minutes before and 24 and 48 hours after cold injury. At 24 hours after cold injury, infarction volumes in the z-VAD.FMK-treated animals were significantly smaller than infarction volumes in the vehicle-treated animals, and were further decreased at 72 hours (0.92 +/- 1.80 mm3, z-VAD.FMK-treated animals; 7.46 +/- 3.53 mm3, vehicle-treated animals; mean +/- SD, n = 7 to 8). The amount of DNA fragmentation was significantly decreased in the z-VAD.FMK-treated animals compared with the vehicle-treated animals, as shown by terminal deoxynucleotidyl transferase-mediated uridine 5'-triphosphate-biotin nick end labeling staining and DNA gel electrophoresis. By Western blot analysis, both the proform and activated form of interleukin-1beta converting enzyme (caspase 1) were detected in the control brain, and the activated form showed moderate reduction after cold injury-induced brain trauma. These results indicate that caspase inhibitors could reduce cold injury-induced brain trauma by preventing neuronal cell death by DNA damage. The caspase family proteases appear to contribute to the mechanisms of cell death in cold injury-induced brain trauma and to provide therapeutic targets for traumatic brain injury.
作者研究了z-VAD.FMK（一种阻断半胱天冬酶家族蛋白酶的抑制剂）对冷损伤诱导的脑损伤的影响，在这种损伤中，细胞凋亡以及坏死都被认为起作用。在冷损伤前15分钟以及冷损伤后24小时和48小时，将单独的溶剂或与z-VAD.FMK一起的溶剂注入小鼠脑室。冷损伤后24小时，z-VAD.FMK处理组动物的梗死体积显著小于溶剂处理组动物，并且在72小时时进一步减小（z-VAD.FMK处理组动物为0.92±1.80立方毫米；溶剂处理组动物为7.46±3.53立方毫米；平均值±标准差，n = 7至8）。如通过末端脱氧核苷酸转移酶介导的尿苷5'-三磷酸生物素缺口末端标记染色和DNA凝胶电泳所示，与溶剂处理组动物相比，z-VAD.FMK处理组动物的DNA片段化量显著减少。通过蛋白质印迹分析，在对照脑中检测到白细胞介素-1β转化酶（半胱天冬酶1）的前体形式和活化形式，并且在冷损伤诱导的脑损伤后活化形式显示出适度减少。这些结果表明，半胱天冬酶抑制剂可以通过防止DNA损伤导致的神经元细胞死亡来减少冷损伤诱导的脑损伤。半胱天冬酶家族蛋白酶似乎在冷损伤诱导的脑损伤中的细胞死亡机制中起作用，并为创伤性脑损伤提供治疗靶点。
