机构:[1]Cerebrovascular Diseases Research Institute, Xuanwu Hospital of Capital Medical University, 45 Changchun Street, Beijing 100053, China首都医科大学?脑血管病研究所首都医科大学宣武医院[2]Key Laboratory of Neurodegenerative Diseases (Capital Medical University), Ministry of Education, 45 Changchun Street, Beijing 100053, China[3]Department of Pharmaceutical Sciences, College of Pharmacy, University of New Mexico, Albuquerque, NM 87131-0001, USA
Autophagy, an important intracellular degradation pathway, has been reported to clear impaired mitochondria and reduce mitochondria-mediated injury in ischemic disease. Our study and other recent investigations have shown that AKT-dependent autophagy contributes to the neuroprotection afforded by limb remote ischemic conditioning (RIC) in experimental stroke. However, how AKT triggers RIC-based autophagy and whether RIC-afforded autophagy is beneficial for mitochondrial function after cerebral ischemia remains unclear. The disruption of the Bcl-2/Beclin1 complex has been reported to trigger autophagy formation in the condition of Bcl-2 phosphorylation at Ser70. We investigated whether Bcl-2 phosphorylation triggers RIC-based autophagy and thereby confers RIC-induced neuroprotection against mitochondrial injury, using a transient cerebral ischemic rat model. We demonstrated that rats undergoing RIC treatment 30 min after the onset of ischemia (I-30) and at reperfusion (R-0) significantly upregulated Bcl-2 phosphorylation. Immunoprecipitation revealed that RIC increased dissociation of the Bcl-2/Beclin1 complex, leading to a higher level of autophagy than in ischemia/reperfusion rats. Furthermore, AKT activation was shown to play a critical role in regulating Bcl-2-mediated autophagy, as an AKT inhibitor (LY294002, AKTi) administered 30 min prior to ischemia significantly suppressed Bcl-2 phosphorylation and Bcl-2/Beclin1 complex dissociation, thereby reducing autophagy in RIC rats. Blocking Bcl-2 phosphorylation-dependent autophagy with AKTi suppressed RIC-afforded protection on mitochondrial potential and mitochondrial-dependent cell death effector pathway. These findings indicate that Bcl-2 phosphorylation and thereby Bcl-2/Beclin1 complex disruption play a crucial role in triggering autophagy and reducing mitochondrial damage in RIC rats after cerebral ischemia and require the involvement of the AKT activation.
基金:
National Natural Science Foundation of China (81271461, 30770743,81200928),
Beijing Nova Program (Z141107001814045),
Beijing Nature Science Foundation (7111003).
第一作者机构:[1]Cerebrovascular Diseases Research Institute, Xuanwu Hospital of Capital Medical University, 45 Changchun Street, Beijing 100053, China[2]Key Laboratory of Neurodegenerative Diseases (Capital Medical University), Ministry of Education, 45 Changchun Street, Beijing 100053, China
通讯作者:
通讯机构:[1]Cerebrovascular Diseases Research Institute, Xuanwu Hospital of Capital Medical University, 45 Changchun Street, Beijing 100053, China[3]Department of Pharmaceutical Sciences, College of Pharmacy, University of New Mexico, Albuquerque, NM 87131-0001, USA
推荐引用方式(GB/T 7714):
Zhifeng Qi,Wen Dong,Wenjuan Shi,et al.Bcl-2 Phosphorylation Triggers Autophagy Switch and Reduces Mitochondrial Damage in Limb Remote Ischemic Conditioned Rats After Ischemic Stroke[J].TRANSLATIONAL STROKE RESEARCH.2015,6(3):198-206.doi:10.1007/s12975-015-0393-y.
APA:
Zhifeng Qi,Wen Dong,Wenjuan Shi,Rongliang Wang,Chencheng Zhang...&Yumin Luo.(2015).Bcl-2 Phosphorylation Triggers Autophagy Switch and Reduces Mitochondrial Damage in Limb Remote Ischemic Conditioned Rats After Ischemic Stroke.TRANSLATIONAL STROKE RESEARCH,6,(3)
MLA:
Zhifeng Qi,et al."Bcl-2 Phosphorylation Triggers Autophagy Switch and Reduces Mitochondrial Damage in Limb Remote Ischemic Conditioned Rats After Ischemic Stroke".TRANSLATIONAL STROKE RESEARCH 6..3(2015):198-206