Redox-Resistant SERCA [Sarco(endo)plasmic Reticulum Calcium ATPase] Attenuates Oxidant-Stimulated Mitochondrial Calcium and Apoptosis in Cardiac Myocytes and Pressure Overload-Induced Myocardial Failure in Mice.
Redox-Resistant SERCA [Sarco(endo)plasmic Reticulum Calcium ATPase] Attenuates Oxidant-Stimulated Mitochondrial Calcium and Apoptosis in Cardiac Myocytes and Pressure Overload-Induced Myocardial Failure in Mice.
复制标题
抗氧化还原SERCA [肌浆网钙ATP酶]减弱小鼠心肌细胞中氧化剂刺激的线粒体钙和凋亡以及压力超负荷诱导的心肌衰竭。
DOI：
10.1161/circulationaha.120.048183
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发表时间：
2020-12-22
期刊：
影响因子：
37.8
通讯作者：
Colucci WS
中科院分区：
文献类型：
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作者：
Goodman JB;Qin F;Morgan RJ;Chambers JM;Croteau D;Siwik DA;Hobai I;Panagia M;Luptak I;Bachschmid M;Tong X;Pimentel DR;Cohen RA;Colucci WS
肌浆网钙ATP酶（SERCA）受半胱氨酸674（C674）处的氧化翻译后修饰调节。由于肌浆网（SR）钙已被证明在介导线粒体功能障碍反应活性氧（ROS）的关键作用，我们假设，在C674的SERCA氧化将调节心肌细胞中的线粒体钙和线粒体依赖性细胞凋亡的ROS的影响。将表达野生型（WT）SERCA 2b或氧化还原不敏感突变体（其中C674被丝氨酸取代（C674 S））的成年大鼠心室肌细胞（ARVM）暴露于H2 O2（100 μM）。使用遗传靶向荧光探针测量ARVM中的游离线粒体钙浓度，并通过测量咖啡因刺激的释放来评估SR钙含量。对具有SERCA C674 S突变（SKI）的杂合敲入的小鼠进行慢性升主动脉缩窄（AAC）。在表达WT SERCA的ARVM中，H2 O2导致线粒体钙浓度增加25%，这与SR钙含量减少50%相关，这两者都被兰尼碱受体抑制剂丁卡因阻止。在表达C674 S突变体的细胞中，基础SR钙含量降低了31%，H2 O2刺激的线粒体钙浓度升高减弱了40%。在WT细胞中，H2 O2引起细胞色素c释放和细胞凋亡，这两者在C674 S表达细胞中被阻止。在SKI小鼠的肌细胞中，基础SERCA活性和SR钙含量降低。为了测试C674氧化对体内细胞凋亡的影响，使SKI小鼠经受慢性AAC。在WT小鼠中，AAC引起肌细胞凋亡、LV扩张和收缩衰竭-所有这些在SKI小鼠中均被抑制。SERCA C674的氧化还原激活调节基础SR钙含量，从而介导心肌细胞凋亡和心肌衰竭所需的病理性ROS刺激的线粒体钙升高。
Sarco(endo)plasmic reticulum calcium ATPase (SERCA) is regulated by oxidative post-translational modifications at cysteine 674 (C674). Since sarcoplasmic reticulum (SR) calcium has been shown to play a critical role in mediating mitochondrial dysfunction in response to reactive oxygen species (ROS), we hypothesized that SERCA oxidation at C674 would modulate the effects of ROS on mitochondrial calcium and mitochondria-dependent apoptosis in cardiac myocytes. Adult rat ventricular myocytes (ARVM) expressing wild-type (WT) SERCA2b or a redox-insensitive mutant in which C674 is replaced by serine (C674S) were exposed to H2O2 (100 μM). Free mitochondrial calcium concentration was measured in ARVM using a genetically-targeted fluorescent probe and SR calcium content was assessed by measuring caffeine-stimulated release. Mice with heterozygous knock-in of the SERCA C674S mutation (SKI) were subjected to chronic ascending aortic constriction (AAC). In ARVM expressing WT SERCA, H2O2 caused a 25% increase in mitochondrial calcium concentration that was associated with a 50% decrease in SR calcium content, both of which were prevented by the ryanodine receptor inhibitor tetracaine. In cells expressing the C674S mutant, basal SR calcium content was decreased by 31% and the H2O2-stimulated rise in mitochondrial calcium concentration was attenuated by 40%. In WT cells, H2O2 caused cytochrome c release and apoptosis, both of which were prevented in C674S-expressing cells. In myocytes from SKI mice, basal SERCA activity and SR calcium content were decreased. To test the effect of C674 oxidation on apoptosis in vivo, SKI mice were subjected to chronic AAC. In WT mice, AAC caused myocyte apoptosis, LV dilation and systolic failure – all of which were inhibited in SKI mice. Redox activation of SERCA C674 regulates basal SR calcium content thereby mediating the pathologic ROS-stimulated rise in mitochondrial calcium required for myocyte apoptosis and myocardial failure.