title: Helix B Surface Peptide Protects against Acute Myocardial Ischemia-Reperfusion Injury via the RISK and SAFE Pathways in a Mouse Model.
abstract: OBJECTIVE
  This study explores the effects of helix B surface peptide (HBSP) on myocardial infarct size (IS), cardiac function, cardiomyocyte apoptosis and oxidative stress damage in mouse hearts subjected to myocardial ischemia-reperfusion injury (MIRI) and also the mechanisms underlying the effects.
  
  
  METHODS
  Male adult mice were subjected to 45 min of ischemia followed by 2 h of reperfusion; 5 min before the reperfusion, they were treated with HBSP or vehicle. MIRI-induced IS, cardiomyocyte apoptosis and cardiac functional impairment were determined and compared. Western blot analysis was then conducted to elucidate the mechanism of HBSP after treatment.
  
  
  RESULTS
  HBSP administration before reperfusion significantly reduced the myocardial IS, decreased cardiomyocyte apoptosis, reduced the activities of superoxide dismutase and malondialdehyde and partially preserved heart function. As demonstrated by the Western blot analysis, HBSP after treatment upregulated Akt/GSK-3β/ERK and STAT-3 phosphorylation; these inhibitors, in turn, weakened the beneficial effects of HBSP.
  
  
  CONCLUSIONS
  HBSP plays a protective role in MIRI in mice by inhibiting cardiomyocyte apoptosis, reducing the MIRI-induced IS, oxidative stress and improving the heart function after MIRI. The mechanism underlying these effects of HBSP is related to the activation of the RISK (reperfusion injury salvage kinase, Akt/GSK-3β/ERK) and SAFE (STAT-3) pathways.
authors.affiliation: Department of Cardiology, Zhujiang Hospital, Southern Medical University, Guangzhou, China.
authors.forename: Peng
authors.initials: P
authors.lastname: Liu
authors.forename: Wei
authors.initials: W
authors.lastname: You
authors.forename: Lin
authors.initials: L
authors.lastname: Lin
authors.forename: Yongluan
authors.initials: Y
authors.lastname: Lin
authors.forename: Xiuying
authors.initials: X
authors.lastname: Tang
authors.forename: Yingfeng
authors.initials: Y
authors.lastname: Liu
authors.forename: Fei
authors.initials: F
authors.lastname: Miao
mesh_terms: D000818:Animals; D017209:Apoptosis / Q000187:drug effects*; D004195:Disease Models, Animal; D004921:Erythropoietin / Q000008:administration & dosage*; D008297:Male; D051379:Mice; D015428:Myocardial Reperfusion Injury / Q000188:drug therapy*; D032383:Myocytes, Cardiac / Q000187:drug effects*; D010446:Peptide Fragments / Q000008:administration & dosage*; D010766:Phosphorylation; D015398:Signal Transduction / Q000187:drug effects*; D016276:Ventricular Function / Q000187:drug effects
chemical_list: D010446:Peptide Fragments; C585201:glutaminyl-glutamyl-glutaminyl-leucyl-glutamyl-arginyl-alanyl-leucyl-asparagyl-seryl-serine; D004921:Erythropoietin