DataSheet1_Propofol Protects Myocardium From Ischemia/Reperfusion Injury by Inhibiting Ferroptosis Through the AKT/p53 Signaling Pathway.ZIP

The molecular mechanism underlying the protective role of propofol against myocardial ischemia/reperfusion (I/R) injury remains poorly understood. Previous studies have shown that ferroptosis is an imperative pathological process in myocardial I/R injury. We hypothesized that propofol prevents myocardial I/R injury by inhibiting ferroptosis via the AKT/p53 signaling pathway. The ferroptosis-inducing agent erastin (E) and AKT inhibitor MK2206 (MK) were used to investigate the role of propofol in myocardial I/R injury. H9C2 cells treated without any reagents, erastin for 24 h, propofol for 1 h before adding erastin were assigned as the control (C), E, and E + P group, respectively. Cell viability, reactive oxygen species (ROS), and the expression of antioxidant enzymes, including ferritin heavy chain 1 (FTH1), cysteine/glutamate transporter (XCT), and glutathione peroxidase 4 (GPX4) in H9C2 cells. Rat hearts from the I/R + P or I/R groups were treated with or without propofol for 20 min before stopping perfusion for 30 min and reperfusion for 60 min. Rat hearts from the I/R + P + MK or I/R + MK groups were treated with or without propofol for 20 min, with a 10-min treatment of MK2206 before stopping perfusion. Myocardial histopathology, mitochondrial structure, iron levels, and antioxidant enzymes expression were assessed. Our results demonstrated that erastin increased H9C2 cell mortality and reduced the expression of antioxidant enzymes. I/R, which reduced the expression of antioxidant enzymes and increased iron or p53 (p < 0.05), boosted myocardium pathological and mitochondrion damage. Propofol inhibited these changes; however, the effects of propofol on I/R injury were antagonized by MK (p < 0.05). In addition, AKT siRNA inhibited the propofol-induced expression of antioxidant enzymes (p < 0.05). Our findings confirm that propofol protects myocardium from I/R injury by inhibiting ferroptosis via the AKT/p53 signal pathway.

丙泊酚（propofol）对抗心肌缺血再灌注（myocardial ischemia/reperfusion, I/R）损伤的保护作用的分子机制目前仍不甚明晰。既往研究表明，铁死亡（ferroptosis）是心肌I/R损伤中至关重要的病理过程。本研究假设丙泊酚可通过AKT/p53信号通路（AKT/p53 signaling pathway）抑制铁死亡，从而减轻心肌I/R损伤。本研究采用铁死亡诱导剂艾拉司他（erastin, E）与AKT抑制剂MK2206（MK），以探究丙泊酚在心肌I/R损伤中的作用。将未施加任何试剂、用艾拉司他处理24小时、以及在加入艾拉司他前先用丙泊酚预处理1小时的H9C2细胞，分别划分为对照组（C组）、E组与E+P组。检测H9C2细胞的细胞活力、活性氧（reactive oxygen species, ROS）水平，以及铁蛋白重链1（ferritin heavy chain 1, FTH1）、胱氨酸/谷氨酸转运体（cysteine/glutamate transporter, XCT）与谷胱甘肽过氧化物酶4（glutathione peroxidase 4, GPX4）等抗氧化酶的表达水平。对于I/R+P组与I/R组大鼠心脏，在停止灌注前分别给予或不给予丙泊酚预处理20分钟，随后停止灌注30分钟并再灌注60分钟。对于I/R+P+MK组与I/R+MK组大鼠心脏，在停止灌注前先给予或不给予丙泊酚预处理20分钟，并在停止灌注前用MK2206处理10分钟。检测指标包括心肌组织病理学、线粒体结构、铁离子水平以及抗氧化酶的表达情况。本研究结果显示，艾拉司他可升高H9C2细胞死亡率并降低抗氧化酶的表达水平。心肌I/R损伤可降低抗氧化酶表达、升高铁离子与p53水平（p<0.05），并加重心肌病理损伤与线粒体损伤。丙泊酚可抑制上述变化，但MK可拮抗丙泊酚对I/R损伤的保护作用（p<0.05）。此外，AKT小干扰RNA（AKT siRNA）可抑制丙泊酚诱导的抗氧化酶表达（p<0.05）。本研究结果证实，丙泊酚可通过AKT/p53信号通路抑制铁死亡，从而保护心肌免受I/R损伤。