对氧磷酶 2 通过调节线粒体功能和氧化应激通过 PI3K/Akt/GSK-3β RISK 途径来保护急性心肌缺血再灌注损伤。

Paraoxonase 2 protects against acute myocardial ischemia-reperfusion injury by modulating mitochondrial function and oxidative stress via the PI3K/Akt/GSK-3β RISK pathway.

机构信息

Department of Medicine, Division of Cardiology, David Geffen School of Medicine, University of California, Los Angeles, United States of America; Molecular Toxicology Interdepartmental Degree Program, University of California, Los Angeles, United States of America.

Department of Anesthesiology, Division of Molecular Medicine, David Geffen School of Medicine, University of California, Los Angeles, United States of America.

出版信息

J Mol Cell Cardiol. 2019 Apr;129:154-164. doi: 10.1016/j.yjmcc.2019.02.008. Epub 2019 Feb 23.

DOI:10.1016/j.yjmcc.2019.02.008

PMID:30802459

Abstract

OBJECTIVE

To investigate the novel role of Paraoxonase 2 (PON2) in modulating acute myocardial ischemia-reperfusion injury (IRI).

APPROACH

IRI was induced both in vivo and ex vivo in male, C57BL6/J (WT) and PON2-deficient (PON-def) mice. In addition, in vitro hypoxia-reoxygenation injury (HRI) was induced in H9c2 cells expressing empty vector (H9c2-EV) or human PON2 (H9c2-hPON2) ± LY294002 (a potent PI3K inhibitor). Infarct size, PON2 gene expression, mitochondrial calcium retention capacity (CRC), reactive oxygen species (ROS) generation, mitochondrial membrane potential, CHOP and pGSK-3β protein levels, and cell apoptosis were evaluated.

RESULTS

PON2 gene expression is upregulated in WT mice following in vivo IRI. PON2-def mice exhibit a 2-fold larger infarct, increased CHOP levels, and reduced pGSK-3β levels compared to WT controls. Global cardiac mitochondria isolated from PON2-def mice exhibit reduced CRC and increased ROS production. Cardiomyocytes isolated from PON2-def mice subjected to ex vivo IRI have mitochondria with reduced CRC (also seen under non-IRI conditions), and increased ROS generation and apoptosis compared to WT controls. PON2 knockdown in H9c2 cells subjected to HRI leads to an increase in mitochondrial membrane depolarization. H9c2-hPON2 cells exhibit i) improvement in mitochondrial membrane potential, pGSK-3β levels and mitochondrial CRC, and ii) decrease in CHOP levels, mitochondrial ROS generation and cell apoptosis, when compared to H9c2-EV controls. Treatment with LY294002 resulted in a decrease of mitochondrial CRC and increase in mitochondrial ROS production and cell apoptosis in the H9c2-hPON2 group versus H9c2-EV controls.

CONCLUSION

PON2 protects against acute myocardial IRI by reducing mitochondrial dysfunction and oxidative stress in cardiomyocytes via activation of the PI3K/Akt/GSK-3β RISK pathway.

摘要

目的

研究对氧磷酶 2（PON2）在调节急性心肌缺血再灌注损伤（IRI）中的新作用。

方法

在雄性 C57BL6/J（WT）和 PON2 缺陷（PON-def）小鼠体内和体外诱导 IRI。此外，在表达空载体（H9c2-EV）或人 PON2（H9c2-hPON2）±LY294002（一种有效的 PI3K 抑制剂）的 H9c2 细胞中诱导体外缺氧再复氧损伤（HRI）。评估梗死面积、PON2 基因表达、线粒体钙保留能力（CRC）、活性氧（ROS）生成、线粒体膜电位、CHOP 和 pGSK-3β 蛋白水平以及细胞凋亡。

结果

WT 小鼠体内 IRI 后 PON2 基因表达上调。与 WT 对照组相比，PON2-def 小鼠的梗死面积增加了 2 倍，CHOP 水平升高，pGSK-3β 水平降低。从 PON2-def 小鼠中分离的心脏线粒体整体表现出 CRC 降低和 ROS 生成增加。来自 PON2-def 小鼠的经历离体 IRI 的心肌细胞的线粒体 CRC 降低（在非 IRI 条件下也可见），并且与 WT 对照组相比，ROS 生成和凋亡增加。在经历 HRI 的 H9c2 细胞中敲低 PON2 导致线粒体膜去极化增加。与 H9c2-EV 对照相比，H9c2-hPON2 细胞表现出 i）改善的线粒体膜电位、pGSK-3β 水平和线粒体 CRC，和 ii）降低的 CHOP 水平、线粒体 ROS 生成和细胞凋亡。与 H9c2-EV 对照相比，LY294002 处理导致 H9c2-hPON2 组的线粒体 CRC 降低和线粒体 ROS 生成和细胞凋亡增加。