Humans ; Myocardial Reperfusion Injury/prevention & control* ; Melatonin/therapeutic use* ; Mitochondria ; Myocardial Infarction

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

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

BACKGROUNDPlasma transfusion is a common clinical practice. Remote ischemic preconditioning (RIPC) protects organs against ischemia-reperfusion (IR) injury. Whether preconditioned plasma (PP), collected at late phase after RIPC, could protect organs against IR injury in vivo is unknown. This study explored whether transfusion of PP could reduce myocardial infarct size (IS) after IR in rat in vivo.

METHODSEighty Lewis rats were randomized to eight groups (n = 10 for each group). Two groups of plasma donor rats donated plasma at 48 h after transient limb ischemia (PP) or control protocol (nonpreconditioned plasma [NPP]). Six groups of recipient rats received normal saline (NS; NS-IR 1, and NS-IR 24 groups), NPP (NPP-IR 1 and NPP-IR 24 groups), or PP (PP-IR 1 and PP-IR 24 groups) at one or 24 h before myocardial IR. Myocardial IR consisted of 30-min left anterior descending (LAD) coronary artery occlusion and 180-min reperfusion. The area at risk (AAR) and infarct area were determined by double-staining with Evans blue and triphenyltetrazolium chloride. IS was calculated by infarct area divided by AAR. This was a 3 × 2 factorial design study, and factorial analysis was used to evaluate the data. If an interaction between the fluid and transfusion time existed, one-way analysis of variance with Bonferroni correction for multiple comparisons was used to analyze the single effects of fluid type when the transfusion time was fixed.

RESULTSIS in the NPP-IR 1 and PP-IR 1 groups was smaller than in the NS-IR 1 group (F = 6.838, P = 0.005; NPP-IR 1: 57 ± 8% vs. NS-IR1: 68 ± 6%, t = 2.843, P = 0.020; PP-IR 1: 56 ± 8% vs. NS-IR 1: 68 ± 6%, t = 3.102, P = 0.009), but no significant difference was detected between the NPP-IR 1 and PP-IR 1 groups (57 ± 8% vs. 56 ± 8%, t = 0.069, P = 1.000). IS in the NPP-IR 24 and PP-IR 24 groups was smaller than in the NS-IR 24 group (F = 24.796, P< 0.001; NPP-IR 24: 56% ± 7% vs. NS-IR 24: 68 ± 7%, t = 3.102, P = 0.026; PP-IR 24: 40 ± 9% vs. NS-IR 24: 68 ± 7%, t = 7.237, P< 0.001); IS in the PP-IR 24 group was smaller than in the NPP-IR 24 group (40 ± 9% vs. 56 ± 7%, t = 4.135, P = 0.002).

CONCLUSIONTransfusion of PP collected at late phase after remote ischemic preconditioning could reduce IS, suggesting that late-phase cardioprotection was transferable in vivo.

Animals ; Blood Component Transfusion ; methods ; Ischemic Preconditioning, Myocardial ; methods ; Male ; Myocardial Infarction ; etiology ; prevention & control ; Myocardial Reperfusion Injury ; complications ; Plasma ; Rats

Mild therapeutic hypothermia of 32-35degrees C improved neurologic outcomes in outside hospital cardiac arrest survivor. Furthermore, in experimental studies on infarcted model and pilot studies on conscious patients with acute myocardial infarction, therapeutic hypothermia successfully reduced infarct size and microvascular resistance. Therefore, mild therapeutic hypothermia has received an attention as a promising solution for reduction of infarction size after acute myocardial infarction which are not completely solved despite of optimal reperfusion therapy. Nevertheless, the results from randomized clinical trials failed to prove the cardioprotective effects of therapeutic hypothermia or showed beneficial effects only in limited subgroups. In this article, we reviewed rationale for therapeutic hypothermia and possible mechanisms from previous studies, effective methods for clinical application to the patients with acute myocardial infarction, lessons from current clinical trials and future directions.
Acute Disease ; Body Temperature ; Humans ; Hypothermia, Induced/*methods ; Male ; Middle Aged ; Myocardial Infarction/*therapy ; Myocardial Reperfusion Injury/*prevention & control ; Time Factors ; Treatment Outcome

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

BACKGROUNDSevoflurane preconditioning (SP) has been shown to invoke potent myocardial protection in animal studies and clinical trials. However, the mechanisms underlying SP are complex and not yet well understood. We investigated the hypothesis that the cardioprotection afforded by SP is mediated via the Wnt/glycogen synthase kinase 3β (GSK3β)/β-catenin signaling pathway.

METHODSTwo models were established: a Langendorff perfused rat heart model and the H9C2 cell hypoxia/reoxygenation model. Both rats and H9C2 cells were randomly divided into 6 groups as follows: S group, ischemia-reperfusion (I/R) group, DMSO group, IWP group, SP group, and SP + IWP group. Hemodynamic parameters, lactate dehydrogenase (LDH) activity in coronary effluent and cell culture supernatant, and the infarct size were measured to evaluate myocardial ischemia-reperfusion injuries. To determine the activity of Wnt/GSK3β/β-catenin signaling pathway, the expressions of Wnt3a, phospho-GSK3β, and β-catenin were measured by Western blotting.

RESULTSSP improved cardiac function recovery, reduced infarct size (18 ± 2% in the SP group compared with 35 ± 4% in the I/R group; P < 0.05), decreased LDH activity in coronary effluent, and culture supernatant. IWP-2, an inhibitor of Wnt, abolished the cardioprotection by SP. In addition, Western blotting analysis demonstrated that the expressions of Wnt3a, phospho-GSK3β, and β-catenin significantly (P < 0.05) increased in the I/R group, compared with the S group; and compared to I/R group, SP significantly (P < 0.05) increased Wnt3a, phospho-GSK3β, and β-catenin expressions. Pretreatment with IWP-2 significantly (P < 0.05) abolished SP-induced Wnt/GSK3β/β-catenin signaling activation.

CONCLUSIONSThe results showed for thefirst time that cardioprotection afforded by SP may be mediated partly via the Wnt/GSK3β/β-catenin signaling pathway.

Animals ; Cell Hypoxia ; drug effects ; Cell Line ; Glycogen Synthase Kinase 3 ; genetics ; metabolism ; Glycogen Synthase Kinase 3 beta ; Hemodynamics ; drug effects ; Male ; Methyl Ethers ; therapeutic use ; Myocardial Reperfusion Injury ; drug therapy ; prevention & control ; Rats ; Rats, Wistar ; Wnt Signaling Pathway ; drug effects ; genetics ; beta Catenin ; genetics ; metabolism

To investigate the protective effect of preconditioning with hyperoside ( Hyp) against myocardial ischemia-reperfusion injury (MIRI) in rats and the role of PI3K/Akt signaling pathway. MIRI was established by ligation of left anterior descending coronary artery for 30 min followed by reperfusion for 120 min in rats. Male SD rats were randomly divided into five groups: sham group,model group (MIRI),Hyp preconditioning group(Hyp), Hyp preconditioning + LY294002 (a PI3K/Akt signaling pathway inhibitor) group (Hyp + LY), and LY294002 group (LY). At the end of reperfusion, hemodynamic parameters were recorded as left ventricular systolic pressure (LVSP) , left ventricular end-diastolic pressure ( LVEDP) and maximal rate of increase and decrease of left ventricular pressure (± dP/dt(max)). Myocardial infaret size, the oxidative stress markers, myocardial enzymes indicators and inflammatory factors were also analyzed. The expressions of Akt, p-Akt, Bax and Bcl-2 proteins was detected by using Western blot method. The results showed that Hyp preconditioning remarkably improved cardiac constriction and relaxation function, reduced myocardial infarct size and enhanced the activities of oxidative stress markers about correlated to MIRI, such as superoxide dismutase (SOD), catalase (CAT) and glutathione-peroxidase (GSH-Px) and decreased the contents of malondialdehyde (MDA) as compared with MIRI group. Simultaneouly, the levels of myocardial enzymes, i. e. creatine kinase ( CK) and creatine kinase MB isoenzyme (CK-MB), and inflammatory factors, for instance tumor necrosis factor-alpha (TNF-α) and interleukin-6 (IL-6) were decreased. Hyp pretreatment apparently restrained myocardial apoptosis as evidenced by decreasing the level of Bax expression, increasing the levels of phosphorylation of Akt and Bcl-2 expression. These effects were inhibited by LY294002, a blocker of PI3K/Akt signaling pathway. These findings indicated that the cardioprotection of Hyp preconditioning against MIRI may be related to activating PI3K/Akt signaling pathway, upregulating the expression of BCL-2 protein and down-regulating the expression of Bax protein.
Animals ; Creatine Kinase ; genetics ; metabolism ; Drugs, Chinese Herbal ; administration & dosage ; Heart ; drug effects ; Humans ; Interleukin-6 ; genetics ; metabolism ; Ischemic Preconditioning, Myocardial ; Male ; Malondialdehyde ; metabolism ; Myocardial Reperfusion Injury ; drug therapy ; enzymology ; genetics ; prevention & control ; Phosphatidylinositol 3-Kinases ; genetics ; metabolism ; Proto-Oncogene Proteins c-akt ; genetics ; metabolism ; Quercetin ; administration & dosage ; analogs & derivatives ; Rats ; Rats, Sprague-Dawley ; bcl-2-Associated X Protein ; genetics ; metabolism

OBJECTIVETo study the protective effect of sufentanil preconditioning against myocardial ischemia-reperfusion (I/R) injury and the role of PI3K/Akt signaling pathway.

METHODSSixty male SD rats weighing 250-350 g were randomly divided into 5 equal groups, namely the sham-operated group, I/R group, sufentanil preconditioning group (Spc group), sufentanil preconditioning +PI3K inhibitor group (Spc+W group), and PI3K inhibitor group (W group). Myocardial I/R model was established by ligation of the anterior descending branch of the left coronary artery for 30 min followed by reperfusion for 120 min. Sufentanil was administered in 3 doses via the femoral vein before the occlusion, each at 1 µg/kg infused within 5 min at a 5-min interval. In Spc+W and W groups, PI3K inhibitor wortmannin (15 µg/kg) was given intravenously 5 min before sufentanil preconditioning and 35 min before ischemia, respectively. Heart rate and mean arterial pressure (MAP) were continuously monitored during I/R. At the end of reperfusion, blood samples were obtained to determine plasma activation of CK-MB and LDH. Acute infarct size was measured by triphenyltetrazolium chloride staining, and the myocardial tissues were obtained to detect the expression of phosphorylated Akt using Western blotting.

RESULTSPhosphorylated Akt expression was significantly up-regulated in I/R and Spc groups as compared with the sham group, and was significantly higher in Spc group than in I/R group. After reperfusion, sufentanil preconditioning significantly decreased myocardial infarct size (P<0.01) and lowered the levels of CK-MB (P<0.01) and LDH (P<0.01) compared with those in the I/R group. The I/R , Spc+W and W groups showed no significant differences in myocardial infarct size or the levels of CK-MB and LDH.

CONCLUSIONThe protective effect of sufentanil preconditioning against myocardium against I/R injury in rats may involve PI3K/Akt signaling pathway activation.

Animals ; Ischemic Preconditioning, Myocardial ; methods ; Male ; Myocardial Reperfusion Injury ; metabolism ; prevention & control ; Proto-Oncogene Proteins c-akt ; metabolism ; Rats ; Signal Transduction ; Sufentanil ; pharmacology

OBJECTIVETo study the effects of dopamin receptors-2 (DR2) on myocardial ischemic postconditioning and explore its underlying mechanisms.

METHODSThe myocardial ischemic postconditioning (PC) model was established in cultured primary rat neonatal cardiomyocytes which were then randomly assigned in the following groups: Nomial control group, Isehemia/reperfusion (L'R) group, PC (ischemic postconditioning) group, PC + Bro (Bromocriptine, a DB2 antagonist) group, PC + Hal (Haloperidol, a DB2 repressor) and PC + Hal + Bro groups. The lactate dehydrogenase (LDH) and superoxide dismutase (SOD) activity and malondialdehyde (MDA) content in cell medium were analyzed by colorunetry. The cell ultrastructure changes were observed by transmission electron microscope. The cell apoptosis was analyzed using flowcytometiy. The protein expression level of D112 and activity of p-p38 and p-JNK were detected by Western blot.

RESULTSCompared with the nonnal control group, hR increased the protein expression level of DB2, enhanced LDH activity and MDA content, promoted cell injury and apoptosis, decreased SOD activity, up-regulated the activity of p-p38 and p-JNK. Compared with the hR group, although PC further increased the expression of DR2 protein, it decreased LDH activity and MDA content, cell injury and apoptosis, increased SOD activity, down-regulated activity of p-p38 and p-JNK. Bromocriptine treatment further enhanced PC-induced canlioprotective effect, yet Hal addition attenuated this enhancing effect exerted by bromocriptine.

CONCLUSIONThe activation of DB2 is involved in the protective effect of ischemic postconditioning on myocardial ischemia/reperfusion injury through down-regulating the activity of p-p38 and p-JNK.

Animals ; Apoptosis ; Cells, Cultured ; Ischemic Postconditioning ; JNK Mitogen-Activated Protein Kinases ; metabolism ; Myocardial Reperfusion Injury ; prevention & control ; Myocytes, Cardiac ; pathology ; Rats ; Rats, Wistar ; Receptors, Dopamine D2 ; physiology ; p38 Mitogen-Activated Protein Kinases ; metabolism