Department of Craniocerebral Surgery, Guangxi International Zhuang Medicine Hospital, Nanning, China.
Department of Neurosurgery, Xiangyang Central Hospital Affiliated to Hubei University of Arts and Science, Xiangyang, China.
J Biochem Mol Toxicol. 2020 Nov;34(11):e22570. doi: 10.1002/jbt.22570. Epub 2020 Jul 13.
Tissue-type plasminogen activator (tPA) is characterized as an effective drug for early thrombolytic therapy in acute cerebral infarction (ACI). However, tPA will increase the risk of hemorrhage if it is used beyond the treatment time window. The study aims to explore the effects of neuroserpin (NSP) on the time window of tPA thrombolysis in ACI and the underlying mechanism. The middle cerebral artery occlusion (MCAO) model was constructed in rats, which were randomly divided into six groups: sham operation group, infarction group, 1-hour thrombolysis group, 1-hour thrombolytic + NSP intervention group, 4-hour thrombolytic group, and 4-hour thrombolysis + NSP intervention group. The neurological changes in rats were evaluated by modified neurological severity scores and rota-rod test. The brain edema and cerebral infarction area were evaluated by dry-wet method and triphenyl tetrazolium chloride staining. The blood-brain barrier (BBB) integrity was examined by Evans blue method. The expressions of malondialdehyde, superoxide dismutase, and glutathione peroxidase in brain were also investigated. The expression of caspase-3 and Bcl-2 in brain tissue and apoptosis of neurons were examined by Western blot analysis and toluidine blue staining. tPA thrombolysis significantly attenuated the neurological impairment in rats with MCAO at 1 hour. Conversely, the effect of tPA thrombolysis at 4 hours after MCAO did not significantly help the recovery of neurological function. However, a combination of tPA treatment and NSP treatment at 4 hours after MCAO markedly ameliorated the neurological impairment, cerebral edema, cerebral infarction volume, BBB injury, oxidative stress products, and neuron apoptosis. NSP can probably expand the time window for tPA treatment to reduce neurological impairment in ACI.
组织型纤溶酶原激活物（tPA）是急性脑梗死（ACI）早期溶栓治疗的有效药物。然而，如果超过治疗时间窗使用，tPA 会增加出血风险。本研究旨在探讨神经丝氨酸蛋白酶抑制剂（NSP）对 ACI 中 tPA 溶栓时间窗的影响及其潜在机制。构建大鼠大脑中动脉闭塞（MCAO）模型，随机分为假手术组、梗死组、1 小时溶栓组、1 小时溶栓+NSP 干预组、4 小时溶栓组和 4 小时溶栓+NSP 干预组。通过改良神经功能缺损评分和转棒试验评估大鼠神经功能变化。采用干湿重法和氯化三苯基四氮唑染色评估脑水肿和脑梗死面积。伊文思蓝法检测血脑屏障（BBB）完整性。还检测了脑内丙二醛、超氧化物歧化酶和谷胱甘肽过氧化物酶的表达。通过 Western blot 分析和甲苯胺蓝染色检测脑组织中 caspase-3 和 Bcl-2 的表达以及神经元凋亡。1 小时 MCAO 后 tPA 溶栓明显减轻大鼠神经损伤。相反，MCAO 后 4 小时 tPA 溶栓的作用并不能显著帮助神经功能恢复。然而，MCAO 后 4 小时 tPA 治疗与 NSP 联合治疗显著改善了神经损伤、脑水肿、脑梗死体积、BBB 损伤、氧化应激产物和神经元凋亡。NSP 可能扩大 tPA 治疗时间窗，减轻 ACI 中的神经损伤。
