Xu Jiajun, Chen Wentong, Yao Jianli
Department of Emergency, Quanzhou First Hospital Affiliated to Fujian Medical University (Quanzhou First Hospital), Quanzhou 362000, Fujian, China. Corresponding author: Xu Jiajun, Email:
Zhonghua Wei Zhong Bing Ji Jiu Yi Xue. 2021 Jan;33(1):74-78. doi: 10.3760/cma.j.cn121430-20200710-00509.
To explore the effects of necroptosis specific inhibitor-1 (Nec-1) on brain injury in rats after cardiac arrest and its mechanism.
A total of 24 Sprague-Dawley (SD) rats were divided into Sham group, model group and Nec-1 group (n = 8 per group) according to random number table method. In the Sham group, only general surgical procedures were underdone without inducing cardiac arrest. In the model group, the rats were subjected to asphyxial cardiac arrest followed by cardiopulmonary resuscitation (CPR) at 6 minutes after cardiac arrest. In the Nec-1 group, Nec-1 of 1 mg/kg was administered after cardiac arrest, and CPR was performed at 6 minutes after cardiac arrest. At 72 hours after CPR, neurological deficit scores (NDS) were assessed, serum S100B levels were measured by enzyme linked immunosorbent assay (ELISA), receptor-interacting protein 3 (RIP3) expression in cerebral cortex and hippocampus was observed under immunofluorescence and positive rate was calculated, and the levels of RIP3 protein expression in brain were analyzed by Western blotting.
At 72 hours after CPR, the rats in the model group showed obvious necroptosis and injury in brain. Compared with the Sham group, the NDS scores in the model group were significantly decreased [57.0 (52.7, 60.0) vs. 80.0 (80.0, 80.0), P < 0.05], the serum S100B was significantly increased (ng/L: 44.9±4.5 vs. 18.6±1.5, P < 0.05), the percentages of RIP3 positive cells in cerebral cortex and hippocampus were significantly elevated [cerebral cortex: (31.7±4.8)% vs. (11.6±3.2)%, hippocampus: (28.4±0.8)% vs. (10.9±0.6)%, both P < 0.05], and the levels of RIP3 protein expression in brain were significantly increased [RIP3 protein (RIP3/GAPDH): 0.708 (0.642, 0.722) vs. 0.408 (0.253, 0.504), P < 0.05]. After Nec-1 intervention, necroptosis and injury in brain were obviously improved. Compared with the model group, the NDS scores at 72 hours after CPR in the Nec-1 group were significantly increased [70.5 (68.5, 71.7) vs. 57.0 (52.7, 60.0), P < 0.05), the serum S100B was significantly decreased (ng/L: 31.9±2.7 vs. 44.9±4.5, P < 0.05), the percentages of RIP3 positive cells in cerebral cortex and hippocampus were significantly lowered [cerebral cortex: (23.7±4.1)% vs. (31.7±4.8)%,hippocampus: (20.4±0.4)% vs. (28.4±0.8)%, both P < 0.05], and the levels of RIP3 protein expression in brain were significantly declined [RIP3 protein (RIP3/GAPDH): 0.437 (0.379, 0.507) vs. 0.708 (0.642, 0.722), P < 0.05].
Nec-1 attenuated necroptosis of brain cells by inhibiting the expression of RIP3 protein, so as to reduce brain injury after cardiac arrest in rats.
探讨坏死性凋亡特异性抑制剂-1（Nec-1）对心脏骤停后大鼠脑损伤的影响及其机制。
将24只Sprague-Dawley（SD）大鼠按随机数字表法分为假手术组、模型组和Nec-1组（每组8只）。假手术组仅进行常规外科手术，不诱导心脏骤停。模型组大鼠采用窒息法致心脏骤停，心脏骤停6分钟后进行心肺复苏（CPR）。Nec-1组在心脏骤停后给予1 mg/kg的Nec-1，心脏骤停6分钟后进行CPR。CPR后72小时，评估神经功能缺损评分（NDS），采用酶联免疫吸附测定（ELISA）法检测血清S100B水平，免疫荧光观察大脑皮质和海马中受体相互作用蛋白3（RIP3）的表达并计算阳性率，蛋白质免疫印迹法分析脑内RIP3蛋白表达水平。
CPR后72小时，模型组大鼠脑内出现明显的坏死性凋亡及损伤。与假手术组比较，模型组NDS评分显著降低[57.0（52.7，60.0）比80.0（80.0，80.0），P<0.05]，血清S100B显著升高（ng/L：44.9±4.5比18.6±1.5，P<0.05），大脑皮质和海马中RIP3阳性细胞百分比显著升高[大脑皮质：（31.7±4.8）%比（11.6±3.2）%，海马：（28.4±0.8）%比（10.9±0.6）%，均P<0.05]，脑内RIP3蛋白表达水平显著升高[RIP3蛋白（RIP3/GAPDH）：0.708（0.642，0.722）比0.408（0.253，0.504），P<0.05]。Nec-1干预后，脑内坏死性凋亡及损伤明显改善。与模型组比较，Nec-1组CPR后72小时NDS评分显著升高[70.5（68.5，71.7）比57.0（52.7，60.0），P<0.05]，血清S100B显著降低（ng/L：31.9±2.7比44.9±4.5，P<0.05），大脑皮质和海马中RIP3阳性细胞百分比显著降低[大脑皮质：（23.7±4.1）%比（31.7±4.8）%，海马：（20.4±0.4）%比（28.4±0.8）%，均P<0.05]，脑内RIP3蛋白表达水平显著下降[RIP3蛋白（RIP3/GAPDH）：0.437（0.379，0.507）比0.708（0.642，0.722），P<0.05]。
Nec-1通过抑制RIP3蛋白表达减轻脑细胞坏死性凋亡，从而减轻大鼠心脏骤停后脑损伤。
