OBJECTIVES: To evaluate whether garlicin post-conditioning can attenuate myocardial ischemiareperfusion injury in a catheter-based porcine model of acute myocardial infarction (AMI) by affecting adhesion molecules integrin β1/CD29 and platelet endothelial cell adhesion molecule-1 (PECAM-1/CD31). METHODS: Twenty-two swine were devided into 3 groups: 6 in a sham-operation group, and 8 each in the model and garlicin groups. AMI porcine model was established in the model and garlicin groups. The distal parts of the left anterior descending coronary artery in the animals of the model and garlicin groups were occluded by dilated balloon for 2 h, followed by reperfusion for 3 h. Garlicin (1.88 mg/kg) was injected over a period of 1 h, beginning just before reperfusion, in the garlicin group. Real-time polymerase chain reaction, immunohistochemistry and Western blot were carried out to detect mRNA and protein expressions of CD29 and CD31 3 h after reperfusion. RESULTS: Hematoxylin-eosin staining showed a better myocardial structure in the garlicin group after reperfusion. Compared to the model group, garlicin inhibited both the mRNA and protein expression of CD29 and CD31 in reperfusion area and no-reflflow area (P<0.05 respectively). CONCLUSIONS Garlicin post-conditioning induced cardio-protection against myocardial ischemia-reperfusion injury in this catheter-based porcine model of AMI. The cardio-protective effect of garlicin is possibly owing to suppression of production of CD29 and CD31, by inhibition of the mRNA expression of CD29 and CD31.
Allyl Compounds ; pharmacology ; Animals ; Disease Models, Animal ; Disulfides ; pharmacology ; Integrin beta1 ; analysis ; genetics ; physiology ; Ischemic Postconditioning ; Male ; Myocardial Reperfusion Injury ; prevention & control ; Platelet Endothelial Cell Adhesion Molecule-1 ; analysis ; antagonists & inhibitors ; genetics ; RNA, Messenger ; analysis ; Swine

BACKGROUND: Endothelial dysfunction, the initial pathogenic factor in atherosclerosis, can be alleviated via transient limb ischemia. We observed the effects of regular transient limb ischemia (RTLI) on atherosclerosis in hypercholesterolemic rabbits. METHODS: Twenty-eight rabbits were randomized to control, cholesterol, sham, ischemia groups (n = 7 each) between October 2010 and March 2011. They were fed a normal diet in the control group and hypercholesterolemic diet in other groups for 12 weeks. Six cycles of RTLI were performed once per day on the ischemia group. Serum samples were prepared to measure the total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C) before the experiment (W0), at the end of weeks 4, 8, 12 (W4, W8, W12). The whole aorta was harvested at W12 and stained using Sudan IV to identify the plaque. The plaque area was measured using Image J. Results were analyzed by analysis of variance or rank sum test. RESULTS: Concentrations of TC in the cholesterol group were higher than those in the control group at W4 (29.60 [23.75, 39.30] vs. 1.00 [0.80, 1.55], Z = -2.745, P = 0.006), W8 (41.78 [28.08, 47.37] vs. 0.35 [0.10, 0.68], Z = -2.739, P = 0.006), W12 (48.32 [40.04, 48.95] vs. 0.61 [0.50, 0.86], Z = -2.739, P = 0.006). Similar results were obtained for HDL-C and LDL-C. Serum concentrations of TC, HDL-C, and LDL-C in the hypercholesterolemic groups had no differences (all P > 0.05). The percentage of plaque area in the cholesterol group was higher than that in the control group (47.22 ± 23.89% vs. 0, Z = -2.986, P = 0.003). Square root of the percentage of plaque area was smaller in the ischemia group than that in the cholesterol (0.44 ± 0.13 vs. 0.67 ± 0.18, P = 0.014) or sham groups (0.44 ± 0.13 vs. 0.61 ± 0.12, P = 0.049). CONCLUSION In hypercholesterolemic rabbits, RTLI might prevent atherosclerosis progression by reducing the percentage of plaque area.
Animals ; Atherosclerosis ; blood ; prevention & control ; Cholesterol ; blood ; Cholesterol, HDL ; blood ; Cholesterol, LDL ; blood ; Extremities ; pathology ; Hypercholesterolemia ; blood ; Ischemic Attack, Transient ; blood ; Ischemic Postconditioning ; methods ; Male ; Rabbits ; Triglycerides ; blood

To investigate whether ischemic postconditioning (IPTC) can promote the recovery of left ventricular impaired regional or global longitudinal systolic function.
 Methods: The trial was divided into a percutaneous coronary intervention (PCI) group, an PCI+IPTC group and a control group. Thirty-two patients with anterior acute anterior wall ST-segment elevation myocardial infarction (STEMI) underwent the first emergency PCI in the PCI group, 28 patients with anterior acute STEMI underwent the combination of PCI and IPTC in the PCI+IPTC group, while 30 patients underwent coronary angiography in the control group. Two-dimensional dynamic echocardiography was collected before operation, 0.5 h, 1 day, 3 days, 1 week, 1 month and 6 months after operation, respectively. The longitudinal strain parameters at different time points were analyzed and compared in the 3 groups.
 Results: The regional longitudinal strain of infracted segments in the PCI+IPTC group after the operation within 1 week was higher than that in the PCI group (P<0.05). The left ventricular global longitudinal strain in the PCI+IPTC group seemed to be higher than that in PCI group after the operation within 1 week, but there was not statistically difference (P>0.05). There was no significant difference in the long-term regional and global longitudinal strains of left ventricle between the PCI+IPTC group and the PCI group (both P>0.05).
 Conclusion: The IPTC can improve the short-term longitudinal systolic function of the reperfused myocardium in patients with acute anterior wall STEMI after PCI.
Anterior Wall Myocardial Infarction ; Humans ; Ischemic Postconditioning ; Myocardium ; Percutaneous Coronary Intervention ; ST Elevation Myocardial Infarction ; Treatment Outcome ; Ventricular Function, Left

BackgroundRemote ischemic postconditioning (RIPostC) appears to protect distant organs from ischemia-reperfusion injury (IRI). However, cerebral protection results have remained inconclusive. In the present study, a meta-analysis was performed to compare stroke patients with and without RIPostC.

MethodsCNKI, WanFang, VIP, CBM, PubMed, and Cochrane Library databases were searched up to July 2016. Data were analyzed using both fixed-effects and random-effects models by Review Manager. For each outcome, risk ratio (RR) and mean difference (MD) with 95% confidence interval (CI) were calculated.

ResultsA total of 13 randomized controlled trials that enrolled a total of 794 study participants who suffered from or are at risk for brain IRI were selected. Compared with controls, RIPostC significantly reduced the recurrence of stroke or transient ischemic attacks (RR = 0.37; 95% CI: 0.26-0.55; P < 0.00001). Moreover, it can reduce the levels of the National Institutes of Health Stroke Scale score (MD: 1.96; 95% CI: 2.18-1.75; P < 0.00001), modified Rankin Scale score (MD: 0.73; 95% CI: 1.20-0.25; P = 0.00300), and high-sensitivity C-reactive protein (MD: 4.17; 95% CI: 4.71-3.62; P < 0.00001) between the two groups. There was no side effect of RIPostC using tourniquet cuff around the limb on ischemic stroke treating based on different intervention duration.

ConclusionThe present meta-analysis suggests that RIPostC might offer cerebral protection for stroke patients suffering from or are at risk of brain IRI.

Brain Ischemia ; prevention & control ; Humans ; Ischemic Attack, Transient ; prevention & control ; therapy ; Ischemic Postconditioning ; methods ; Randomized Controlled Trials as Topic ; Stroke ; prevention & control

OBJECTIVE: Ischemic postconditioning (IPostC), consisted of transient brain ischemia/reperfusion cycles, is considered to have neuroprotective effect. However, there is no best single protocol of IPostC, because varied factors like species tested and characteristics of the tissue may affect the efficacy of IPostC. Thus, we investgated whether different protocols of IPostC affect neuroprotective effects in experimental animal models. MATERIALS AND METHODS: Through occlusion of middle cerebral artery (MCA) with intraluminal suture, stroke was induced in a transient focal ischemia model in mice. We conducted IPostC via brief and repeated MCA occlusion, 2 minutes after reperfusion, followed by different ischemia and reperfusion protocols. After procedure, functional neurological score and histological examination were evaluated. RESULTS: IPostC with different protocols resulted in diverse effects. Among them, a protocol that consists of 3 cycle of IPostC significantly reduced the infarction size 3 days after stroke. CONCLUSION: IPostC was confirmed to reduce infarction size. The effects of IPostC are definitely affected by differences in the protocol used, including the number of cycles, the duration of individual ischemia/reperfusion episode and the entire duration of the IPostC stimuli.
Animals ; Brain ; Infarction* ; Ischemia ; Ischemic Postconditioning* ; Mice ; Middle Cerebral Artery ; Models, Animal ; Neuroprotective Agents ; Reperfusion ; Stroke* ; Sutures

BACKGROUND AND OBJECTIVES: Information about the role of the stromal cell-derived factor-1α (SDF-1α)/chemokine receptor type 4 (CXCR4) axis in ischemic postconditioning (IPOC) is currently limited. We hypothesized that the SDF-1α/CXCR4 signaling pathway is directly involved in the cardioprotective effect of IPOC. METHODS: Isolated rat hearts were divided into four groups. The control group was subjected to 30-min of regional ischemia and 2-hour of reperfusion (n=12). The IPOC group was induced with 6 cycles of 10-second reperfusion and 10-second global ischemia (n=8) in each cycle. The CXCR4 antagonist, AMD3100, was applied before reperfusion in the IPOC group (AMD+IPOC group, n=11) and control group (AMD group, n=9). Hemodynamic changes with electrocardiography were monitored and infarct size was measured. The SDF-1α, lactate dehydrogenase (LDH) and creatine kinase (CK) concentrations in perfusate were measured. We also analyzed extracellular signal-regulated kinase 1/2 (ERK1/2) and Akt phosphorylation state expression. RESULTS: IPOC significantly reduced infarct size, but AMD3100 attenuated the infarct reducing effect of IPOC. IPOC significantly decreased LDH and CK, but these effects were reversed by AMD3100. ERK1/2 and Akt phosphorylation increased with IPOC and these effects were blocked by AMD3100. CONCLUSION: Based on the results of this study, SDF-1α/CXCR4 signaling may be involved in IPOC cardioprotection and this signaling pathway couples to the ERK1/2 and Akt pathways.
Animals ; Creatine Kinase ; Electrocardiography ; Family Characteristics ; Heart* ; Hemodynamics ; Ischemia ; Ischemic Postconditioning* ; L-Lactate Dehydrogenase ; Phosphorylation ; Phosphotransferases ; Rats* ; Receptors, CXCR4 ; Reperfusion ; Reperfusion Injury

BACKGROUNDIt is well documented that sevoflurane postconditioning (SP) has a significant myocardial protection effect. However, the mechanisms underlying SP are still unclear. In the present study, we investigated the hypothesis that the Pim-1 kinase played a key role in SP-induced cardioprotection by regulating dynamics-related protein 1 (Drp1).

METHODSA Langendorff model was used in this study. Seventy-two rats were randomly assigned into six groups as follows: CON group, ischemia reperfusion (I/R) group, SP group , SP+proto-oncogene serine/threonine-protein kinase 1 (Pim-1) inhibitor II group, SP+dimethylsufoxide group, and Pim-1 inhibitor II group (n = 12, each). Hemodynamic parameters and infarct size were measured to reflect the extent of myocardial I/R injury. The expressions of Pim-1, B-cell leukemia/lymphoma 2 (Bcl-2) and cytochrome C (Cyt C) in cytoplasm and mitochondria, the Drp1 in mitochondria, and the total Drp1 and p-Drp1ser637 were measured by Western blotting. In addition, transmission electron microscope was used to observe mitochondrial morphology. The experiment began in October 2014 and continued until July 2016.

RESULTSSP improved myocardial I/R injury-induced hemodynamic parametric changes, cardiac function, and preserved mitochondrial phenotype and decreased myocardial infarct size (24.49 ± 1.72% in Sev group compared with 41.98 ± 4.37% in I/R group; P< 0.05). However, Pim-1 inhibitor II significantly (P < 0.05) abolished the protective effect of SP. Western blotting analysis demonstrated that, compared with I/R group, the expression of Pim-1 and Bcl-2 in cytoplasm and mitochondria as well as the total p-Drp1ser637 in Sev group (P < 0.05) were upregulated. Meanwhile, SP inhibited Drp1 compartmentalization to the mitochondria followed by a reduction in the release of Cyt C. Pretreatment with Pim-1 inhibitor II significantly (P < 0.05) abolished SP-induced Pim-1/p-Drp1ser637 signaling activation.

CONCLUSIONSThese findings suggested that SP could attenuate myocardial ischemia-reperfusion injury by increasing the expression of the Pim-1 kinase. Upregulation of Pim-1 might phosphorylate Drp1 and prevent extensive mitochondrial fission through Drp1 cytosolic sequestration.

Animals ; Dynamins ; metabolism ; Hemodynamics ; drug effects ; Ischemic Postconditioning ; methods ; Male ; Methyl Ethers ; therapeutic use ; Mitochondria ; drug effects ; metabolism ; Myocardial Reperfusion Injury ; metabolism ; prevention & control ; Proto-Oncogene Proteins c-pim-1 ; antagonists & inhibitors ; metabolism ; Quinazolinones ; pharmacology ; Rats ; Rats, Sprague-Dawley

BACKGROUND AND OBJECTIVES: Ischemic post-conditioning (PostC) has been demonstrated as a novel strategy to harness nature's protection against myocardial ischemia-reperfusion (I/R). Hypercholesterolemia (HC) has been reported to block the effect of PostC on the heart. Angiotensin II type-1 (AT1) modulators have shown benefits in myocardial ischemia. The present study investigates the effect of a novel inhibitor of AT1, azilsartan in PostC of the heart of normocholesterolemic (NC) and HC rats. MATERIALS AND METHODS: HC was induced by the administration of high-fat diet to the animals for eight weeks. Isolated Langendorff's perfused NC and HC rat hearts were exposed to global ischemia for 30 min and reperfusion for 120 min. I/R-injury had been assessed by cardiac hemodynamic parameters, myocardial infarct size, release of tumor necrosis factor-alpha troponin I, lactate dehydrogenase, creatine kinase, nitrite in coronary effluent, thiobarbituric acid reactive species, a reduced form of glutathione, superoxide anion, and left ventricle collagen content in normal and HC rat hearts. RESULTS: Azilsartan post-treatment and six episodes of PostC (10 sec each) afforded cardioprotection against I/R-injury in normal rat hearts. PostC protection against I/R-injury was abolished in HC rat hearts. Azilsartan prevented the HC-mediated impairment of the beneficial effects of PostC in I/R-induced myocardial injury, which was inhibited by L-N⁵-(1-Iminoethyl)ornithinehydrochloride, a potent inhibitor of endothelial nitric oxide synthase (eNOS). CONCLUSION: Azilsartan treatment has attenuated the HC-induced impairment of beneficial effects of PostC in I/R-injury of rat hearts, by specifically modulating eNOS. Azilsartan may be explored further in I/R-myocardial injury, both in NC and HC conditions, with or without PostC.
Angiotensin II ; Animals ; Collagen ; Creatine Kinase ; Diet, High-Fat ; Glutathione ; Heart ; Heart Ventricles ; Hemodynamics ; Hypercholesterolemia ; Ischemia ; Ischemic Postconditioning* ; L-Lactate Dehydrogenase ; Myocardial Infarction ; Myocardial Ischemia ; Nitric Oxide Synthase Type III ; Rats ; Reperfusion ; Reperfusion Injury ; Superoxides ; Troponin I ; Tumor Necrosis Factor-alpha

To explore the protective effects of right coronary artery ischemic preconditioning and post-conditioning on myocardial ischemia reperfusion injury in rabbit heart.
 Methods: A total of 30 rabbits were randomly divided into 4 groups: a control group (n=7), an ischemia reperfusion group (IR group, n=8), an ischemic preconditioning group (IPC group, n=8) and an ischemic post-conditioning group (IPO group, n=7). Venous blood samples were taken at pre-operation, 1 and 6 h post-operation, and the concentration of serum creatine kinase isoenzyme (CK-MB) and cardiac troponin-T (cTn-T) were measured. The infarct area of cardiac muscle was calculated.
 Results: Compared with the IR group, the levels of CK-MB and cTn-T at 1 and 6 h post-operation in the IPC group and the IPO group were reduced (all P<0.05). Compared with the IR group, the infarct size in the IPC group and the IPO group was significantly decreased, with significant difference (both P<0.05) .
 Conclusion: Right coronary artery ischemic preconditioning and post-conditioning exert significant protective effects on the myocardial ischemia reperfusion injury in New Zealand rabbits.
Animals ; Coronary Vessels ; Creatine Kinase, MB Form ; blood ; Heart ; Ischemia ; Ischemic Postconditioning ; Ischemic Preconditioning ; Ischemic Preconditioning, Myocardial ; Myocardial Infarction ; etiology ; pathology ; physiopathology ; prevention & control ; Myocardial Ischemia ; complications ; therapy ; Myocardial Reperfusion Injury ; prevention & control ; Myocardium ; Rabbits ; Troponin T ; blood

OBJECTIVETo establish a model of hypoxic postconditioning of dermal microvascular endothelial cells.

METHODSDuring reoxygenation after hypoxia, cells received three times of hypoxic/ reoxygenation alternate treatment for a certain time. The cells were seeded on 6-well plates, with one plate for one group. They were divided into 6 groups as group 1 ( Control), group 2 (8h hypoxia + 24h reoxygenation), group 3 (8h hypoxia + 2 min x 3 times post-hypoxia treatment) , group 4 (8h hypoxia + 5 min x 3 times post-hypoxia treatment), group 5 (8h hypoxia + 10 min x 3 times post-hypoxia treatment), 6 group (8h hypoxia + 20 min x 3 times post-hypoxia treatment). Each group underwent 8 h hypoxia + 24 h hypoxia Buffer and reoxygenation. Lactate dehydrogenase (LDH) was detected during the process. Apoptosis rate was calculated by staining Tunel method. Bcl-2, Bax and activated caspase-3 protein were detected by Western Blot.

RESULTSIn the continuous hypoxia process, the LDH was (1563 ± 83.35) IU/L at 8h and (582.85 ± 58.25 ) IU/L at 0h, showing a statistical difference (P = 0.0001). Western blotting results showed that the expression of Bax/Bcl-2 in group 2 was 0.38 ± 0.02, showing a significant difference when compared with that in group 3 (0.23 ± 0.01) and group 4 (0.22 ± 0.02) (P = 0.012, P = 0.005), while not when compared with that in group 5 (0.33 ± 0.02) and 6 groups (0.34 ± 0.01) P > 0.05). The ratio of Activated caspase-3/caspase-3 in group 2 (6.30 ± 1.50) was significantly higher than that in group 3 (2.17 ± 0.26) and group 4 (2.63 ± 0.31) (P = 0.008, P = 0.019); while not in group 5 (4.36 ± 0.29) and group 6 (4.97 ± 0.51) (P > 0.05).

CONCLUSIONSThe model of hypoxic postconditioning of human dermal microvascular endothelial cells is successfully established.

Apoptosis ; Blotting, Western ; Caspase 3 ; analysis ; Cell Hypoxia ; Endothelial Cells ; metabolism ; Humans ; In Situ Nick-End Labeling ; Ischemic Postconditioning ; methods ; L-Lactate Dehydrogenase ; analysis ; Oxygen Consumption ; Proto-Oncogene Proteins c-bcl-2 ; analysis ; Time Factors ; bcl-2-Associated X Protein ; analysis