Remote Ischemic Postconditioning Protects against Myocardial Ischemia-Reperfusion Injury by Inhibition of the RAGE-HMGB1 Pathway.

BACKGROUND: The aim of the present study was to observe the effect of RAGE-HMGB1 signal pathway on remote ischemic postconditioning in mice with myocardial ischemia reperfusion injury. METHODS: Mice model of MIRI was established and randomly divided into three groups: control group, ischemia reperfusion group, and remote ischemic postconditioning group. Infarction size was detected by Evans blue and TTC staining. Cardiac function was detected by echocardiography measurement. The protein levels of RAGE, HMGB1, P-AKT, and ERK1/2 were detected by Western blot 120 min following reperfusion. RESULTS: RIPostC could decrease the infarct size and increase LVEF and FS compared with I/R group. Two hours after myocardial ischemia reperfusion, the levels of RAGE and HMGB1 were significantly decreased in RIPostC group compared with those in I/R group. The level of p-AKT was significantly higher in the RIPostC group than in the I/R group. LY294002 significantly attenuated RIPostC-increased levels of Akt phosphorylation. CONCLUSION: RIPostC may inhibit the expression of RAGE and HMGB1 and activate PI3K/Akt signaling pathway to extenuate ischemic reperfusion injury in mice. It could further suppress the oxidative stress, have antiapoptosis effect, and reduce inflammatory reaction, but this effect has certain timeliness.

Effect of Remote Ischemic Preconditioning on Perioperative Cardiac Events in Patients Undergoing Elective Percutaneous Coronary Intervention: A Meta-Analysis of 16 Randomized Trials.

BACKGROUND: The main objective of this meta-analysis was to investigate whether remote ischemic preconditioning (RIPC) reduces cardiac and renal events in patients undergoing elective cardiovascular interventions. METHODS AND RESULTS: We systematically searched articles published from 2006 to 2016 in PubMed, EMBASE, Web of Science, Cochrane Library, and Google Scholar. Odds ratios (ORs) with 95% confidence intervals (CIs) were used as the effect index for dichotomous variables. The standardized mean differences (SMDs) with 95% CIs were calculated as the pooled continuous effect. Sixteen RCTs of 2435 patients undergoing elective PCI were selected. Compared with control group, RIPC could significantly reduce the incidence of perioperative myocardial infarction (OR = 0.64; 95% CI: 0.48-0.86; P = 0.003) and acute kidney injury (OR = 0.56; 95% CI: 0.322-0.99; P = 0.049). Metaregression analysis showed that the reduction of PMI by RIPC was enhanced for CAD patients with multivessel disease (coef.: -0.05 [-0.09; -0.01], P = 0.022). There were no differences in the changes of cTnI (P = 0.934) and CRP (P = 0.075) in two groups. CONCLUSION: Our meta-analysis of RCTs demonstrated that RIPC can provide cardiac and renal protection for patients undergoing elective PCI, while no beneficial effect on reducing the levels of cTnI and CRP after PCI was reported.