铁死亡抑制剂Ferrostatin-1在心肺转流大鼠认知功能中的作用

Effect of ferroptosis inhibitor Ferrostatin-1 on postoperative cognitive function of rats undergoing cardiopulmonary bypass

目的探讨铁死亡抑制剂Ferrostatin-1在心肺转流(CPB)大鼠认知功能中的作用。方法选择SPF级健康雄性SD大鼠24只,12周龄,体重350~400 g。采用随机数字表法将大鼠分为三组:假手术组(S组)、CPB组(C组)和CPB+Ferrostatin-1组(F组),每组8只。S组行股动静脉及颈内静脉穿刺置管,不进行CPB;C组穿刺置管后行CPB 60 min;F组术前腹腔注射Ferrostatin-15 mg/kg,60 min后穿刺置管并行CPB 60 min。于术后第3天行水迷宫实验,记录潜伏期和穿越平台次数。处死大鼠,采用ELISA法检测海马组织活性氧(ROS)、丙二醛(MDA)、谷胱甘肽(GSH)浓度,亚铁嗪比色法检测海马组织Fe^(2+)浓度,Western blot法检测海马组织τau蛋白、β-淀粉样蛋白(Aβ)和谷胱甘肽过氧化物酶4(GPX4)蛋白含量,HE染色观察海马组织锥体细胞病理变化,透射电镜观察海马组织锥体细胞线粒体结构。结果与S组比较,C组和F组潜伏期明显延长(P<0.05),穿越原平台次数明显减少(P<0.05),海马组织ROS、MDA、Fe^(2+)浓度、τau蛋白和Aβ蛋白含量明显升高(P<0.05),GSH浓度和GPX4蛋白含量明显降低(P<0.05),海马组织锥体细胞核固缩,线粒体损伤加重。与C组比较,F组潜伏期明显缩短(P<0.05),穿越原平台次数明显增多(P<0.05),海马组织ROS、MDA、Fe^(2+)浓度、τau蛋白和Aβ蛋白含量明显降低(P<0.05),GSH浓度和GPX4蛋白含量明显升高(P<0.05),海马组织锥体细胞病理结构和线粒体损伤减轻。结论CPB诱导大鼠海马组织神经元发生铁死亡,诱发大鼠术后认知功能障碍,Ferrostatin-1通过抑制铁死亡降低大鼠海马组织ROS、MDA、Fe^(2+)浓度和τau、Aβ蛋白含量,改善CPB大鼠的术后认知功能。

Objective To evaluate the effect of ferroptosis inhibitor Ferrostatin-1 on postoperative cognitive function of rats undergoing cardiopulmonary bypass(CPB).Methods Twenty-four SPF healthy male SD rats,aged 12 weeks,weighing 350-400 g,were divided into three groups using a random number table method:sham operation group(group S),CPB group(group C),and CPB+Ferrostatin-1 group(group F),8 rats in each group.Group S was performed femoral arteriovenous and internal jugular vein puncture catheterization without CPB.Group C received CPB for 60 minutes after catheterization.Group F received intraperitoneal injection of Ferrostatin-15 mg/kg,followed by CPB for 60 minutes after puncture and catheterization 60 minutes later.The water maze experiment was performed on the third postoperative day,and the latency period and the times of platform crossing were recorded.After the water maze test,rats were killed,the concentrations of reactive oxygen species(ROS),malondialdehyde(MDA)and glutathione(GSH)in hippocampal neurons were detected by ELISA,the concentration of Fe^(2+)in hippocampus was determined by ferrozine colorimetry,the expressions ofτau protein,Aβprotein,and glutathione peroxidase 4(GPX4)protein in hippocampus were detected by Western blot.HE staining was used to observe pathological changes in hippocampal neurons,the mitochondrial structure of hippocampal neurons was observed under transmission electron microscope.Results Compared with group S,the latency period was significantly prolonged(P<0.05),the times of platform crossing was significantly decreased(P<0.05),the concentrations of Fe^(2+),ROS,and MDA,the expression of Aβprotein andτau protein in hippocampus were significantly increased(P<0.05),the concentration of GSH and the expression of GPX4 protein were significantly decreased in groups C and F(P<0.05),hippocampal neurons and mitochondria were damaged.Compared with group C,the latency period was significantly shortened(P<0.05),and the number of platform crossing was significantly increased(P<0.05),the concentrations of Fe^(2+),ROS,and MDA,the expression of Aβprotein andτau protein in hippocampus were significantly decreased(P<0.05),the concentration of GSH and the expression of GPX4 protein were significantly increased in group F(P<0.05),hippocampal pathology and mitochondrial damage were relieved.Conclusion CPB induces ferroptosis in rat hippocampal neurons and induces postoperative cognitive dysfunction in rats.Ferrostatin-1 reduces concentrations of ROS,MDA,and Fe^(2+),andτau and Aβprotein content in hippocampal tissue of rats by inhibiting ferroptosis,thus improving postoperative cognitive function of CPB rats.