Transient mitochondrial permeability transition pore opening mediates preconditioning-induced protection
Transient mitochondrial permeability transition pore opening mediates preconditioning-induced protection
复制标题
DOI：
10.1161/01.cir.0000126294.81407.7d
复制
发表时间：
2004-04-13
期刊：
影响因子：
37.8
通讯作者：
Yellon, D
中科院分区：
文献类型：
--
作者：
Hausenloy, D;Wynne, A;Yellon, D
背景-线粒体通透性转换孔(MPTP)的瞬时(低电导)开放可能限制线粒体钙负荷并介导线粒体活性氧(ROS)信号转导。我们假设短暂的MPTP开放和ROS介导了与心肌预适应和线粒体解偶联相关的保护作用。方法和结果：分离的灌流大鼠心脏造成35min的缺血/120min的再灌流，用四唑盐染色测定心肌梗死危险体积比。用环孢素A(CsA，0.2mumol/L)或桑地黄素-A(SFA，1.0mumol/L)抑制MPTP的开放可取消缺血预适应的保护作用(CsA组20.2±-3.6%vs45.9+/-2.5%，SFA组49.0+/-7.1%；P<；0.001)；二氮嗪(Dzx，30mMol/L)(22.1+/-2.7%比CsA的46.3+/-3.0%；SFA：48.4+/-5.5%；P<；0.001)、环磷酰胺(腺苷A1受体激动剂，200nmol/L)(24.9+/-4.5%比CsA的54.4+/-6.6%；0.001)，或2，4-二硝基苯酚(DNP，线粒体解偶联剂，50 Mol/L)(15.7+/-2.7%对CsA：40.8+/-5.5%，SFA；P<；0.001：34.3+/-3.1%)，这表明在这些环境中，需要在预适应阶段开放MPTP来介导保护。在用N-巯基丙酰甘氨酸(MPG，1 mmoL/L)抑制ROS时，IPC(20.2+/-3.6%比MPG；P<；0.001：47.1+/-3.8%)、二氮卓(22.1+/-2.7%比MPG；P<；0.001：56.3+/-3.8%)和DNP(15.7+/-2.7%比MPG；P<；0.001)，而不是CCPA(24.9+/-4.5%vs26.5+/-8.4%，P=NS)。在成年大鼠心肌细胞上的进一步实验表明，二氮嗪诱导CsA敏感的、低电导的瞬时MPTP开放(表现为线粒体钙黄绿素荧光与对照组相比减少28+/-3%；P<；0.01)。结论-我们报道了与IPC、二氮卓和线粒体去偶联相关的保护作用需要瞬时MPTP开放和ROS。
Background - Transient (low-conductance) opening of the mitochondrial permeability transition pore (mPTP) may limit mitochondrial calcium load and mediate mitochondrial reactive oxygen species (ROS) signaling. We hypothesize that transient mPTP opening and ROS mediate the protection associated with myocardial preconditioning and mitochondrial uncoupling.Methods and Results - Isolated perfused rat hearts were subjected to 35 minutes of ischemia/ 120 minutes of reperfusion, and the infarct-risk-volume ratio was determined by tetrazolium staining. Inhibiting mPTP opening during the preconditioning phase with cyclosporine-A (CsA, 0.2 mumol/L) or sanglifehrin-A (SfA, 1.0 mumol/L) abolished the protection associated with ischemic preconditioning (IPC) ( 20.2 +/- 3.6% versus 45.9 +/- 2.5% with CsA, 49.0 +/- 7.1% with SfA; P < 0.001); and pharmacological preconditioning with diazoxide (Dzx, 30 mu mol/L) (22.1 +/- 2.7% versus 46.3 +/- 3.0% with CsA, 48.4 +/- 5.5% with SfA; P < 0.001), CCPA ( the adenosine A1-receptor agonist, 200 nmol/L) (24.9 +/- 4.5% versus 54.4 +/- 6.6% with CsA, 42.6 +/- 9.0% with SfA; P < 0.001), or 2,4-dinitrophenol (DNP, the mitochondrial uncoupler, 50 mu mol/L) (15.7 +/- 2.7% versus 40.8 +/- 5.5% with CsA, 34.3 +/- 3.1% with SfA; P < 0.001), suggesting that mPTP opening during the preconditioning phase is required to mediate protection in these settings. Inhibiting ROS during the preconditioning protocols with N-mercaptopropionylglycine (MPG, 1 mmol/L) also abolished the protection associated with IPC (20.2 +/- 3.6% versus 47.1 +/- 3.8% with MPG; P < 0.001), diazoxide (22.1 +/- 2.7% versus 56.3 +/- 3.8% with MPG; P < 0.001), and DNP (15.7 +/- 2.7% versus 50.7 +/- 6.6% with MPG; P < 0.001) but not CCPA (24.9 +/- 4.5% versus 26.5 +/- 8.4% with MPG; P = NS). Further experiments in adult rat myocytes demonstrated that diazoxide induced CsA-sensitive, low-conductance transient mPTP opening (represented by a 28 +/- 3% reduction in mitochondrial calcein fluorescence compared with control; P < 0.01).Conclusions - We report that the protection associated with IPC, diazoxide, and mitochondrial uncoupling requires transient mPTP opening and ROS.