title: HO-1 Protects against Hypoxia/Reoxygenation-Induced Mitochondrial Dysfunction in H9c2 Cardiomyocytes.
abstract: Mitochondrial dysfunction would ultimately lead to myocardial cell apoptosis and death during ischemia-reperfusion injuries. Autophagy could ameliorate mitochondrial dysfunction by autophagosome forming, which is a catabolic process to preserve the mitochondrial's structural and functional integrity. HO-1 induction and expression are important protective mechanisms. This study in order to investigate the role of HO-1 during mitochondrial damage and its mechanism.
  
  
  
  The H9c2 cardiomyocyte cell line were incubated by hypoxic and then reoxygenated for the indicated time (2, 6, 12, 18, and 24 h). Cell viability was tested with CCK-8 kit. The expression of endogenous HO-1(RT-PCR and Western blot) increased with the duration of reoxygenation and reached maximum levels after 2 hours of H/R; thereafter, the expression gradually decreased to a stable level. Mitochondrial dysfunction (Flow cytometry quantified the ROS generation and JC-1 staining) and autophagy (The Confocal microscopy measured the autophagy. RFP-GFP-LC3 double-labeled adenovirus was used for testing.) were induced after 6 hours of H/R. Then, genetic engineering technology was employed to construct an Lv-HO1-H9c2 cell line. When HO-1 was overexpressed, the LC3II levels were significantly increased after reoxygenation, p62 protein expression was significantly decreased, the level of autophagy was unchanged, the mitochondrial membrane potential was significantly increased, and the mitochondrial ROS level was significantly decreased. Furthermore, when the HO-1 inhibitor ZnPP was applied the level of autophagy after reoxygenation was significantly inhibited, and no significant improvement in mitochondrial dysfunction was observed.
  
  
  
  During myocardial hypoxia-reoxygenation injury, HO-1 overexpression induces autophagy to protect the stability of the mitochondrial membrane and reduce the amount of mitochondrial oxidation products, thereby exerting a protective effect.
authors.affiliation: Department of Anesthesiology, Zhongnan Hospital of Wuhan University, Wuhan, China.
authors.forename: Dongling
authors.initials: D
authors.lastname: Chen
authors.affiliation: Department of Anesthesiology, Zhongnan Hospital of Wuhan University, Wuhan, China.
authors.forename: Zhe
authors.initials: Z
authors.lastname: Jin
authors.affiliation: Department of Anesthesiology, Zhongnan Hospital of Wuhan University, Wuhan, China.
authors.forename: Jingjing
authors.initials: J
authors.lastname: Zhang
authors.affiliation: Department of Anesthesiology, Zhongnan Hospital of Wuhan University, Wuhan, China.
authors.forename: Linlin
authors.initials: L
authors.lastname: Jiang
authors.affiliation: Department of Anesthesiology, Zhongnan Hospital of Wuhan University, Wuhan, China.
authors.forename: Kai
authors.initials: K
authors.lastname: Chen
authors.affiliation: Department of Anesthesiology, Zhongnan Hospital of Wuhan University, Wuhan, China.
authors.forename: Xianghu
authors.initials: X
authors.lastname: He
authors.affiliation: Department of Ophthalmology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.
authors.forename: Yinwei
authors.initials: Y
authors.lastname: Song
authors.affiliation: Department of Anesthesiology, Zhongnan Hospital of Wuhan University, Wuhan, China.
authors.forename: Jianjuan
authors.initials: J
authors.lastname: Ke
authors.affiliation: Department of Anesthesiology, Zhongnan Hospital of Wuhan University, Wuhan, China.
authors.forename: Yanlin
authors.initials: Y
authors.lastname: Wang
mesh_terms: D000818:Animals; D017209:Apoptosis / Q000187:drug effects; D001343:Autophagy / Q000187:drug effects; D015687:Cell Hypoxia / Q000187:drug effects; D002460:Cell Line; D002470:Cell Survival / Q000187:drug effects; D019610:Cytoprotection / Q000187:drug effects; D004790:Enzyme Induction / Q000187:drug effects; D004791:Enzyme Inhibitors / Q000494:pharmacology; D015971:Gene Expression Regulation, Enzymologic; D051547:Heme Oxygenase-1 / Q000037:antagonists & inhibitors / Q000096:biosynthesis / Q000235:genetics / Q000378:metabolism*; D008928:Mitochondria / Q000187:drug effects / Q000378:metabolism* / Q000473:pathology; D032383:Myocytes, Cardiac / Q000166:cytology* / Q000187:drug effects / Q000378:metabolism*; D010100:Oxygen / Q000378:metabolism*; D011524:Protoporphyrins / Q000494:pharmacology; D051381:Rats; D015398:Signal Transduction / Q000187:drug effects
chemical_list: D004791:Enzyme Inhibitors; D011524:Protoporphyrins; C017803:zinc protoporphyrin; D051547:Heme Oxygenase-1; D010100:Oxygen