Activated Drp1 regulates p62-mediated autophagic flux and aggravates inflammation in cerebral ischemia-reperfusion via the ROS-RIP1/RIP3-exosome axis  

作　　者：Xue Zeng Yun-Dong Zhang Rui-Yan Ma Yuan-Jing Chen Xin-Ming Xiang Dong-Yao Hou Xue-Han Li He Huang Tao Li Chen-Yang Duan 

机构地区：[1]Department of Anaesthesiology,the Second Affiliated Hospital of Chongqing Medical University,Chongqing 400010,China [2]Department of Neurology,the Third Affliated Hospital of Chongqing Medical University,Chongqing 401120,China [3]Department of Cardiovascular Surgery,Xinqiao Hospital,Army Medical University,Chongqing 400037,China [4]State Key Laboratory of Trauma,Burns and Combined Injury,Department of Shock and Transfusion,Daping Hospital,Army Medical University,Chongqing 400042,China

出　　处：《Military Medical Research》2022年第6期668-685,共18页军事医学研究（英文版）

基　　金：supported by the National Natural Science Foundation of China (81700429);the China Postdoctoral Science Foundation (2021MD703924);the Chongqing Postdoctoral Innovative Talents Support Program (CQBX2021018);the Kuanren Talents Program of the second affiliated hospital of Chongqing Medical University。

摘　　要：Background: Cerebral ischemia-reperfusion injury(CIRI) refers to a secondary brain injury that can occur when the blood supply to the ischemic brain tissue is restored. However, the mechanism underlying such injury remains elusive.Methods: The 150 male C57 mice underwent middle cerebral artery occlusion(MCAO) for 1 h and reperfusion for 24 h,Among them, 50 MCAO mice were further treated with Mitochondrial division inhibitor 1(Mdivi-1) and 50 MCAO mice were further treated with N-acetylcysteine(NAC). SH-SY5Y cells were cultured in a low-glucose culture medium for 4 h under hypoxic conditions and then transferred to normal conditions for 12 h. Then, cerebral blood flow, mitochondrial structure, mitochondrial DNA(mtDNA) copy number, intracellular and mitochondrial reactive oxygen species(ROS),autophagic flux, aggresome and exosome expression profiles, cardiac tissue structure, mitochondrial length and cristae density, mtDNA and ROS content, as well as the expression of Drp1-Ser616/Drp1, RIP1/RIP3, LC3 II/I, TNF-α,IL-1β, etc., were detected under normal or Drp1 interference conditions.Results: The mtDNA content, ROS levels, and Drp1-Ser616/Drp1 were elevated by 2.2, 1.7 and 2.7 times after CIRI(P<0.05). However, the high cytoplasmic LC3 II/I ratio and increased aggregation of p62 could be reversed by 44%and 88% by Drp1 short hairpin RNA(shRNA)(P<0.05). The low fluorescence intensity of autophagic flux and the increased phosphorylation of RIP3 induced by CIRI could be attenuated by ROS scavenger, NAC(P<0.05). RIP1/RIP3inhibitor Necrostatin-1(Nec-1) restored 75% to a low LC3 II/I ratio and enhanced 2 times to a high RFP-LC3 after Drp1 activation(P<0.05). In addition, although CIRI-induced ROS production caused no considerable accumulation of autophagosomes(P>0.05), it increased the packaging and extracellular secretion of exosomes containing p62 by 4–5 times, which could be decreased by Mdivi-1, Drp1 shRNA, and Nec-1(P<0.05). Furthermore, TNF-α and IL-1βincreased in CIRI-derived exosomes could increase RIP3 phosp

关 键 词：Cerebral ischemia-reperfusion(CIRI) Oxygen-glucose deprivation/reoxygenation(OGD/R) Drp1 P62 LC3 II/I Reactive oxygen species(ROS) RIP1/RIP3 Autophagy EXOSOME Inflammatory 

分 类 号：R743.3[医药卫生—神经病学与精神病学]