Activation of volume-sensitive Cl- channel mediates autophagy-related cell death in myocardial ischaemia/reperfusion injury.
Excessive reactive oxygen species (ROS) plays an important role in myocardial ischemia/reperfusion (I/R) injury, which triggers not only myocardial cellular apoptosis but also autophagy-related cell death, in which volume-sensitive outwardly rectifying (VSOR) Cl- channel-activated by ROS contributes to cell apoptotic volume decrease, playing an incipient incident of cellular apoptosis. However, whether VSOR Cl- channel concurrently participates in autophagy-related cell death regulation remains unclear. To illuminate the issue, studies underwent in myocardial vitro and vivo I/R model. Rats were performed to ischemia 30 minutes and subsequent reperfusion 24-96 hours, ROS scavenger (NAC), VSOR Cl- channel blocker (DCPIB) and autophagy inhibitor (3MA) were administered respectively. Results showed that oxidative stress, LC3-II stain and inflammation in myocardial tissue were markedly increased, lysosome associated membrane protein-2 (LAMP2) were significantly reduced with I/R group as compared with sham group, reperfusion significantly led to damage in myocardial tissue and heart function, whereas the disorder could be rescued through these agents. Moreover, primary neonatal rat cardiomyocytes hypoxia/reoxygenation model were administered, results showed that VSOR Cl- channel-activated by reoxygenation could cause both cell volume decrease and intracellular acidification, which further increased LC3 and depleted of LAMP2, resulting in autophagy-related cell death. Interestingly, VSOR Cl- channel-blocked by DCPIB could stably maintain the cell volume, intracellular pH, abundant LAMP2 and autophagic intensity regardless of ROS intension derived from reoxygenation injury or adding H2O2. These results first demonstrate that VSOR Cl- channel-activated is a pivotal event to trigger autophagy-related death, which reveals a novel therapeutic target to decrease myocardial I/R injury.
Department of Geriatrics, Xijing Hospital, Fourth Military Medical University, Xi'an, China.
Yuesheng
Y
Xia
Department of Geriatrics, Xijing Hospital, Fourth Military Medical University, Xi'an, China.
Yan
Y
Liu
Department of Preventive Medicine, Sun Yat-sen University, Guangzhou, China.
Tong
T
Xia
Department of Geriatrics, Xijing Hospital, Fourth Military Medical University, Xi'an, China.
Xing
X
Li
Department of Geriatrics, Xijing Hospital, Fourth Military Medical University, Xi'an, China.
Cong
C
Huo
Department of Geriatrics, Xijing Hospital, Fourth Military Medical University, Xi'an, China.
Xin
X
Jia
Department of Geriatrics, Xijing Hospital, Fourth Military Medical University, Xi'an, China.
Lin
L
Wang
Department of Geriatrics, Xijing Hospital, Fourth Military Medical University, Xi'an, China.
Rong
R
Xu
Department of Geriatrics, Xijing Hospital, Fourth Military Medical University, Xi'an, China.
Ning
N
Wang
Department of Cardiology, Xijing Hospital, Fourth Military Medical University, Xi'an, China.
Mingming
M
Zhang
Department of Geriatrics, Xijing Hospital, Fourth Military Medical University, Xi'an, China.
Hong
H
Li
Department of Geriatrics, Xijing Hospital, Fourth Military Medical University, Xi'an, China.
Xiaoming
X
Wang
D000225:Adenine / Q000031:analogs & derivatives / Q000737:chemistry; D000818:Animals; D017209:Apoptosis; D001343:Autophagy; D049109:Cell Proliferation; D018118:Chloride Channels / Q000378:metabolism*; D016207:Cytokines / Q000378:metabolism; D006863:Hydrogen-Ion Concentration; D000860:Hypoxia; D007249:Inflammation; D052119:Lysosomal-Associated Membrane Protein 2 / Q000378:metabolism; D008247:Lysosomes / Q000378:metabolism; D008297:Male; D008869:Microtubule-Associated Proteins / Q000378:metabolism; D017202:Myocardial Ischemia / Q000473:pathology*; D009206:Myocardium / Q000473:pathology; D018384:Oxidative Stress; D034622:RNA Interference; D051381:Rats; D017207:Rats, Sprague-Dawley; D017382:Reactive Oxygen Species / Q000378:metabolism; D015427:Reperfusion Injury / Q000473:pathology*
D000225:Adenine; D018118:Chloride Channels; D016207:Cytokines; D052119:Lysosomal-Associated Membrane Protein 2; D008869:Microtubule-Associated Proteins; D017382:Reactive Oxygen Species; C526109:Anxa3 protein, rat; C025946:3-methyladenine
Pathology Section; VSOR Cl- channel; autophagy; cell death; ischemia/reperfusion injury; reactive oxygen species