Attenuation of delayed neuronal death after mild focal ischemia in mice by inhibition of the caspase family
Attenuation of delayed neuronal death after mild focal ischemia in mice by inhibition of the caspase family
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DOI：
10.1097/00004647-199803000-00002
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发表时间：
1998-03-01
影响因子：
6.3
通讯作者：
Moskowitz, MA
中科院分区：
文献类型：
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作者：
Endres, H;Namura, S;Moskowitz, MA
细胞凋亡和兴奋性毒性细胞死亡抑制剂可减少短暂性和永久性大脑中动脉闭塞后的脑损伤。我们比较了两种caspase家族抑制剂与n -甲基- d -天冬氨酸受体拮抗剂(+)-MK-801马来酸氢（MK-801）在一种新特征的环己亚胺敏感小鼠短暂性大脑中动脉闭塞（30分钟）模型中的神经保护作用，其中凋亡细胞死亡突出。24小时再灌注时，2,3,5-三苯基四氯唑染色未检测到缺血性梗死，但在苏木精-伊红染色切片上，72小时和7天纹状体明显出现缺血性梗死。凋亡标志物，如寡核体DNA损伤（阶梯）和末端脱氧核苷酸转移酶介导的dutp -生物素镍端标记（TUNEL）阳性细胞在24小时首次出现，并在再灌注后72小时和7天显著增加。tunel标记的细胞主要是神经元，胶质细胞（GFAP，胶质纤维酸蛋白）和白细胞特异性标志物（CD-45）染色为阴性。半胱天冬酶抑制剂n -苄基羰基-缬氨酸- α - asp -氟甲基酮（z-VAD.FMK；脑室内120 ng）或n -苄基羰基- asp - glul -缬氨酸- asp -氟甲基酮（z-DEVD.FMK；脑室内480 ng）在再灌注6小时后可减少梗死面积和神经功能缺损。与较长时间缺血或永久性闭塞模型相比，其保护程度更大，治疗窗口从大脑中动脉闭塞2小时后的0 ~ 1小时延长至短暂缺血后至少6小时。同时,z-VAD。FMK和z-DEVD。凝胶电泳后定量放射自显像显示，FMK治疗减少了寡核体DNA损伤（DNA阶梯）。相比之下，MK-801仅在缺血前（3 mg/kg腹腔注射）给予脑组织保护，而在再灌注后3或6小时则没有。尽管MK-801预处理后梗死面积减少，但DNA阶梯的数量在再灌注后72小时没有减少，从而表明其机制不同于抑制细胞凋亡。因此，30分钟的可逆性缺血增加了凋亡细胞的死亡，这可以通过延迟z-VAD来减轻。FMK和z-DEVD。FMK给药与神经功能的保存。相比之下，MK-801的治疗窗口期不会超过阻断时间，这可能是因为其主要作用机制不会阻断凋亡细胞死亡的发展。
Inhibitors of apoptosis and of excitotoxic cell death reduce brain damage after transient and permanent middle cerebral artery occlusion. We compared the neuroprotective effects of two caspase family inhibitors with the N-methyl-D-aspartate receptor antagonist (+)-MK-801 hydrogen maleate (MK-801) in a newly characterized cycloheximide-sensitive murine model of transient middle cerebral artery occlusion (30 minutes) in which apoptotic cell death is prominent. Ischemic infarction, undetected by 2,3,5-triphenyltetrazolium chloride staining at 24-hour reperfusion, featured prominently in the striatum at 72 hours and 7 days on hematoxylin-eosin-stained sections. Markers of apoptosis, such as oligonucleosomal DNA damage (laddering) and terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick-end labeling (TUNEL)-positive cells first appeared at 24 hours and increased significantly at 72 hours and 7 days after reperfusion. The TUNEL-labeled cells were mostly neurons and stained negative for glial (GFAP, glial fibrillary acid protein) and leukocyte specific markers (CD-45). The caspase inhibitors, N-benzyloxycarbonyl-Val-Ala-Asp-fluoromethyl ketone (z-VAD.FMK; 120 ng intracerebroventricularly) or N-benzyloxycarbonyl-Asp-Glu-Val-Asp-fluoromethyl ketone (z-DEVD.FMK; 480 ng intracerebroventricularly) decreased infarct size and neurologic deficits when administered 6 hours after reperfusion. The extent of protection was greater than in models of more prolonged ischemia or after permanent occlusion, and the therapeutic window was extended from 0 to 1 hours after 2-hour middle cerebral artery occlusion to at least 6 hours after brief ischemia. Also, z-VAD.FMK and z-DEVD.FMK treatment decreased oligonucleosomal DNA damage (DNA laddering) as assessed by quantitative autoradiography after gel electrophoresis, By contrast, MK-801 protected brain tissue only when given before ischemia (3 mg/kg intraperitoneally), but not at 3 or 6 hours after reperfusion, Despite a decrease in infarct size after MK-801 pretreatment, the amount of DNA laddering did not decrease 72 hours after reperfusion, thereby suggesting a mechanism distinct from inhibition of apoptosis. Hence, 30 minutes of reversible ischemia augments apoptotic cell death, which can be attenuated by delayed z-VAD.FMK and z-DEVD.FMK administration with preservation of neurologic function. By contrast, the therapeutic window for MK-801 does not extend beyond the time of occlusion, probably because its primary mechanism of action does not block the development of apoptotic cell death.