OBJECTIVE: To observe the degree of myocardial cell injury and the changes in autophagy level in rats with myocardial ischemia/reperfusion (I/R) injury induced by cardiopulmonary bypass (CPB), and to explore the regulatory role of the long non-coding RNA-urothelial carcinoma antigen 1-microRNA-143-Notch1 axis (lncRNA-UCA1-miR-143-Notch1 axis) in myocardial I/R injury induced by CPB. METHODS: Healthy male Sprague-Dawley (SD) rats were randomly divided into the following groups using the random number method: Sham operation (Sham) group, myocardial I/R injury model group (model group), empty lentivirus group, lncRNA-UCA1 upregulation group, miR-143 downregulation group, and lncRNA-UCA1 upregulation+miR-143 upregulation group, with 9 rats in each group. The rat model of myocardial I/R injury induced by CPB was established by thoracotomy aortic ligation under cardiopulmonary bypass support; in the Sham group, only threading was performed without ligation, and other procedures were the same. Seventy-two hours before modeling, the lncRNA-UCA1 upregulated group was injected with 100 μL of myocardial tissue-specific adeno-associated virus (AAV) overexpression vector of lncRNA-UCA1 via tail vein, the miR-143 downregulated group was injected with 100 μL of AAV short hairpin RNA (shRNA) vector of miR-143 via tail vein, the lncRNA-UCA1 upregulation+miR-143 upregulation group was injected with 100 μL of myocardial tissue-AAV overexpression vector of lncRNA-UCA1 and 100 μL of AAV overexpression vector of miR-143 via tail vein, and the empty vector lentivirus group was injected with 100 μL of AAV empty vector (virus titers were 1×10⁹ TU/mL); the Sham group and the model group were injected with equal amounts of normal saline. The animals were euthanized 24 hours after intervention and cardiac tissue specimens were collected. After hematoxylin eosin (HE) staining, the damage of myocardial cells and the changes of muscle fiber tissue were observed under a light microscope; after dual staining with uranyl acetate and lead citrate, the ultrastructural damage of heart tissue was observed under a transmission electron microscopy; the expression of lncRNA-UCA1, miR-143, and Notch1 mRNA in myocardial tissue was detected by real-time fluorescence quantitative reverse transcription-polymerase chain reaction (RT-PCR); the expression of microtubule 1 light chain 3-II/I (LC3-II/I) and Notch1 protein in myocardial tissue was detected by Western blotting. RESULTS: Compared with the Sham group, the myocardial cells of rats in the model group were enlarged, the intercellular space increased, autophagosomes increased, the arrangement of myocardial fibers was disordered, mitochondrial proliferated and deformed. The expression levels of lncRNA-UCA1 and Notch1 mRNA, as well as the protein expression levels of LC3-II/I and Notch1 were significantly increased, while the expression level of miR-143 was significantly decreased. Compared with the model group, the degree of myocardial cell injury in the lncRNA-UCA1 upregulation group and miR-143 downregulation group was significantly alleviated, the expression levels of Notch1 mRNA, LC3-II/I, and Notch1 protein were significantly increased [Notch1 mRNA (2^-ΔΔCt): 2.66±0.24, 2.03±0.23 vs. 1.45±0.13, LC3-II/I: 2.10±0.21, 1.92±0.19 vs. 1.39±0.14, Notch1 protein (Notch1/GAPDH): 1.72±0.16, 1.57±0.16 vs. 1.34±0.13, all P < 0.05], and the expression level of miR-143 was significantly decreased (2^-ΔΔCt: 0.50±0.06, 0.52±0.06 vs.0.71±0.06, P < 0.05). The expression level of lncRNA-UCA1 in the lncRNA-UCA1 upregulated group was significantly higher than that in the model group (2^-ΔΔCt: 2.47±0.22 vs. 1.43±0.14, P < 0.05), while there was no significant difference in the miR-143 downregulation group compared with the model group (2^-ΔΔCt: 1.50±0.16 vs. 1.43±0.14, P > 0.05). There was no significant difference in the degree of myocardial cell injury in the empty load lentivirus group and the lncRNA-UCA1 upregulation+miR-143 upregulation group compared to the model group. There were no significant differences in the expression of miR-143, Notch1 mRNA, and the autophagy level in these two groups compared to the model group. The expression level of lncRNA-UCA1 in the lncRNA-UCA1 upregulation+miR-143 upregulation group was significantly higher than that in the model group (2^-ΔΔCt: 2.47±0.20 vs. 1.43±0.14, P < 0.05). CONCLUSIONS Autophagy is involved in the pathological process of myocardial I/R injury induced by CPB. The lncRNA-UCA1-microRNA-143-Notch1 axis may regulate the autophagy level to participate in the I/R injury process.
Animals ; MicroRNAs ; Rats, Sprague-Dawley ; RNA, Long Noncoding ; Male ; Myocardial Reperfusion Injury/etiology* ; Rats ; Cardiopulmonary Bypass/adverse effects* ; Receptor, Notch1/metabolism* ; Autophagy

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

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

To study the therapeutic effect and possible mechanism of icariin on myocardial ischemia-reperfusion injury ( MIRI) model in diabetes rats. The model of diabetic rats were induced by Streptozotocin (STZ), then the model of MIRI was established by ligating the reversible left anterior descending coronary artery for 30 min, and then reperfusing for 120 min. totally 40 male SD were randomly divided into five groups: the control group (NS), the ischemia reperfusion group (NIR), the diabetes control group (MS), the diabetic ischemia reperfusion group (MIR) and the diabetic ischemia reperfusion with icariin group (MIRI). The changes in blood glucose, body weight and living status were observed; the enzyme activity of serum CK-MB, LDH, GSH-Px and myocardium SOD and the content MDA and NO in myocardium were detected; the myocardial pathological changes were observed by HE staining; the myocardial Caspase-3, the Bcl-2, Bax protein expressions were detected by Western blot. The result showed that the diabetes model was successfully replicated; myocardial ischemia-reperfusion injury was more serious in diabetes rats; icariin can increase NO, SOD, GSH-Px, Bcl-2 protein expression, decrease MDA formation, CK-MB and LDH activities and Caspase-3 and Bcl-2 protein expressions and myocardial damage. The result suggested that icariin may play a protective role against ischemia reperfusion myocardial injury in diabetes rats by resisting oxidative stress and inhibiting cell apoptosis.
Animals ; Apoptosis ; drug effects ; Caspase 3 ; metabolism ; Creatine Kinase ; metabolism ; Diabetes Mellitus, Type 2 ; complications ; Drugs, Chinese Herbal ; administration & dosage ; Flavonoids ; administration & dosage ; Humans ; Ischemia ; drug therapy ; etiology ; physiopathology ; Male ; Malondialdehyde ; metabolism ; Myocardial Reperfusion Injury ; drug therapy ; etiology ; metabolism ; physiopathology ; Myocardium ; metabolism ; Proto-Oncogene Proteins c-bcl-2 ; metabolism ; Rats ; Rats, Sprague-Dawley ; Superoxide Dismutase ; metabolism ; bcl-2-Associated X Protein ; metabolism

OBJECTIVETo explore the effect of Danlou Tablet (DT) on arrhythmia model rats induced by transient myocardial ischemia/reperfusion (I/R).

METHODSTotally 45 healthy Wistar rats were randomly divided into 3 groups, the sham-operation group, the model group, and the DT group, 15 in each group. Rats in the sham-operation group and the model group were administered with distilled water by gastrogavage at the daily dose of 0.1 mL/kg. Rats in the DT group was administered with 0.53 g/mL DT suspension by gastrogavage at the daily dose of 0.1 mL/kg. All medication was lasted for 10 successive days. The myocardial I/R experiment was performed at 1 h after the last gastrogavage. ECG was performed before ligation and at I/R. The jugular arterial blood pressure of all rats was measured during the whole course. ST segment changes were observed at each time point of I/R. The ventricular fibrillation, the premature ventricular, the number and the duration of ventricular tachycardia within 30 min reperfusion were also observed. Activities of Na(+)-K+ ATPase and Ca2+ ATPase in the myocardium homogenate were detected as well.

RESULTSThe jugular arterial blood pressure and the heart rate were slightly lower in the DT group than in the model group, but with no statistical difference (P > 0.05). Compared with the sham-operation group, the degree of ST segment was obviously elevated in the model group at 0, 5, and 7 min (P < 0.05). It was significantly lower in the DT group than in the model group (P < 0.01). ST seg ment was more elevated at 5 min than at 0 min in the model group, but the degree of ST segment elevation was still obviously lower in the DT group than in the model group (P < 0.05). There was no statistical difference in the degree of ST segment elevation at 7 min between the two groups (P > 0.05). At 0 min when the decrement of ST segment exceeded one half the ischemia, there was no statistical difference in the degree of myocardial ischemia between the model group and the DT group (P > 0.05). Compared with the model group, the incidence of fatal and nonfatal ventricular fibrillation, the frequency and duration of ventricular tachycardia and premature ventricular beats were obviously lessened, and activities of Na(+)-K+ ATPase and Ca(2+)-ATPase increased (all P < 0.05).

CONCLUSIONSDT could significantly protect arrhythmias induced by transient I/R. Its effect might be related to lowering the degree of myocardial ischemia, and increasing ion transport channel related enzyme activities.

Animals ; Arrhythmias, Cardiac ; drug therapy ; etiology ; Disease Models, Animal ; Drugs, Chinese Herbal ; therapeutic use ; Male ; Myocardial Reperfusion Injury ; complications ; Rats ; Rats, Wistar

To study the antiarrhythmic effect of the newly developed alpha/beta-blocker TJ0711, a variety of animal models of arrhythmia were induced by CaCl2, ouabain and ischemia/reperfusion. Glass microelectrode technique was used to observe action potentials of right ventricular papillary muscle of guinea pig. The onset time of arrhythmia induced by CaCl2 was significantly prolonged by TJ0711 at 0.75, 1.5 and 3 mg x kg(-1) doses. TJ0711 (1.5 and 3 mg x kg(-1)) can significantly shorten the ventricular tachycardia (VT) and ventricular fibrillation (VF) duration, the incidence of VF and mortality were significantly reduced. On ischemia-reperfusion-induced arrhythmic model, TJ0711 (0.25, 0.5, 1 and 2 mg x kg(-1)) can significantly reduce the ventricular premature contraction (PVC), VT, VF incidence, mortality, arrhythmia score with a dose-dependent manner. At the same time, rats serum lactate dehydrogenase (LDH) and creatine kinase (CK) activities decreased significantly by TJ0711 (1 and 2 mg x kg(-1)). Ouabain could cause arrhythmia in guinea pigs, when TJ0711 (0.375, 0.75, 1.5 and 3 mg x kg(-1)) was given, the doses of ouabain inducing a variety of arrhythmia PVC, VT, VF, cardiac arrest (CA) were significantly increased with a dose-dependent manner. In the TJ0711 0.1-30 micromol x L(-1) concentration range, guinea pig right ventricular papillary muscle action potential RP (rest potential), APA (action potential amplitude) and V(max) (maximum velocity of depolarization) were not significantly affected. APD20, APD50 and APD90 had a shortening trend but no statistical difference with the increase of TJ0711 concentration. TJ0711 has antiarrhythmic effect on the sympathetic nerve excitement and myocardial cell high calcium animal arrhythmia model. Myocardial action potential zero phase conduction velocity and resting membrane potential were not inhibited by TJ0711. APD20, APD50 and APD90 were shortened by TJ0711 at high concentration. Its antiarrhythmic action mechanism may be besides the action of blocking beta1 receptor, may also have a strong selective blocking action on alpha1 receptor and reducing intracellular calcium concentration.
Action Potentials ; drug effects ; Adrenergic alpha-Antagonists ; administration & dosage ; pharmacology ; Adrenergic beta-Antagonists ; administration & dosage ; pharmacology ; Animals ; Anti-Arrhythmia Agents ; administration & dosage ; pharmacology ; Arrhythmias, Cardiac ; blood ; chemically induced ; etiology ; pathology ; physiopathology ; Calcium Chloride ; Creatine Kinase ; blood ; Dose-Response Relationship, Drug ; Female ; Guinea Pigs ; Heart Ventricles ; cytology ; Lactate Dehydrogenases ; blood ; Male ; Myocardial Reperfusion Injury ; complications ; Myocytes, Cardiac ; drug effects ; physiology ; Ouabain ; Papillary Muscles ; cytology ; Phenoxypropanolamines ; administration & dosage ; pharmacology ; Random Allocation ; Rats ; Rats, Sprague-Dawley

OBJECTIVETo investigate the effects and mechanisms of hawthorn leaves flavonoids (HLF) on acute myocardial ischemia/reperfusion in anesthetized dogs.

METHODSThe acute ischemia models were prepared by ligating left anterior descending (LAD) artery for 60 min. Qualified 15 male dogs were randomly divided into 3 groups with 5 in each group: blank control (treated with normal saline 3 mL/kg) group, HLF low dosage (5 mg/kg) group and high dosage (10 mg/kg) group, with an once injection through a femoral vein 5 min before reperfusion. Epicardial electrocardiogram was adopted to measure the scope and degree of myocardial ischemia. Simultaneously, neutrophil infiltration in infarct (Inf) and remote site (RS) of myocardial tissue was measured by myeloperoxidase (MPO) activity assay. The serum interleukin-1 (IL-1) and tumor necrosis factorα (TNF-α) content were quantified by radioimmuno-assay. Furthermore, expression of G protein-coupled receptor kinase 2 (GRK2) and nuclear factor κB (NF-κB) in Inf and RS tissue were detected by Western blotting technique.

RESULTSIschemia and reperfusion increased the MPO activity and IL-1 and TNF-α content. HLF (10 and 5 mg/kg) could significantly decrease the degree and scope of myocardial ischemia; markedly inhibit the increase of MPO activity, and IL-1 and TNF-α content induced by myocardial ischemia/infarction. Furthermore, HLF increased GRK2 expression and inhibited NF-κB expression in Inf tissue.

CONCLUSIONHLF could improve the situation of acute myocardial ischemia and inhibit the inflammation in anesthetized dogs, which might be due to its increasing effect on the GRK2 and NF-κB expressions.

Anesthesia ; Animals ; Crataegus ; chemistry ; Dogs ; Drug Evaluation, Preclinical ; Flavonoids ; pharmacology ; therapeutic use ; Inflammation ; etiology ; prevention & control ; Male ; Myocardial Ischemia ; complications ; drug therapy ; pathology ; Myocardial Reperfusion Injury ; complications ; drug therapy ; Neutrophil Infiltration ; drug effects ; Plant Extracts ; pharmacology ; therapeutic use ; Plant Leaves ; chemistry ; Random Allocation

OBJECTIVETo inquire the characteristic proteins in chronic myocardial ischemia by testing twodimensional electrophoresis (2-DE) map to explore the possible inherent pathological mechanism and the therapeutic intervention of qi deficiency and blood stasis syndrome.

METHODSAmeroid constrictor ring was placed on the first interval of left anterior descending coronary artery to prepare chronic myocardial ischemia model on Chinese miniature swine. Animals were randomly divided into sham group and model group with 10 animals in each group, respectively. The dynamic symptoms observation of the four diagnostic information was collected from 0 to 12 weeks. Echocardiography was employed to evaluate cardiac function and the degree of myocardial ischemia, 2-DE and matrix-assisted laser desorption/ionization-time of flight mass spectrometry (MALDI-TOF-MS) were used to carry out proteomics research on animals. Enzyme-linked immunosorbent assay was applied to identify the relevant differential proteins on chronic myocardial ischemia with qi deficiency and blood stasis syndrome.

RESULTSThe preliminary study found that at the 12th week, chronic myocardial ischemia with qi deficiency and blood stasis syndrome model was established stably. Compared with the sham group, there were 8 different proteins down-regulated, 22 proteins up-regulated significantly. After validated by MALDITOF-MS/MS, 11 protein spots were identified. Distinct proteins were mainly associated with energy metabolism and myocardial structural injury, including isocitrate dehydrogenase 3 (NAD+) alpha, NADH dehydrogenase (NAD) Fe-S protein 1, chain A (crystal structure of aldose reductase by binding domain reveals a new Nadph), heat shock protein 27 (HSP27), oxidoreductase (NAD-binding protein), antioxidant protein isoform, cardiac troponin T (cTnT), myosin (myosin light polypeptide), cardiac alpha tropomyosin, apolipoprotein A-I and albumin.

CONCLUSIONDown-regulated energy metabolism disorder mediated by NADH respiratory chain and myocardial injury may be the pathogenesis of myocardial ischemia with qi deficiency and blood stasis syndrome. These proteins may be the potential diagnostic marker(s) for qi deficiency and blood stasis syndrome, finally provided new clues for new therapeutic drug target of Chinese medicine.

Animals ; Blood Coagulation Disorders ; complications ; metabolism ; Electrophoresis, Gel, Two-Dimensional ; Energy Metabolism ; physiology ; Metabolic Diseases ; etiology ; metabolism ; Myocardial Ischemia ; complications ; metabolism ; Myocardial Reperfusion Injury ; etiology ; metabolism ; Proteomics ; methods ; Qi ; Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization ; Swine ; Swine, Miniature ; Syndrome

OBJECTIVETo observe the effect of dopamine receptor (DR2) activation on hypoxia/reperfusion injury (HRI) in the neonatal rat cardiomyocytes, and to explore its mechanism.

METHODSThe hypoxia/reperfusion (H/R) injury model was established in primarily cultured neonatal rat cardiomyocytes, and randomly assigned: control, H/R, bromocriptine (Bro) and haloperidol (Hal) groups. The cell apoptosis was detected using inverted microscope, transmission electron microscope and flow cytometry (FCM). The lactate dehydrogenase(LDH) and superoxide dismutase (SOD) activity and malondialdehyde (MDA) content in cell medium were analyzed. The expression of mRNA and protein of caspase-3, caspase-8, caspase-9, Fas, Fas-L, Cyt C and Bcl-2 were detected by RT-PCR and Western blot, respectively.

RESULTSCompared with the control group, apoptosis rate, LDH activity, MDA content and the expression of pro-apoptotic factors and anti-apoptotic factors were increased, but SOD activity was decreased in H/R group. Compared with the H/R group, all index above-mentioned were down-regulated or reversed in Bro-group, and had no obvious differences in Hal-group.

CONCLUSIONThe neonatal rat cardiomyocytes injury and apoptosis caused by hypoxia/reperfusion can be inhibited with DR2 activation, which mechanism is related to scavenging oxygen radical.

Animals ; Animals, Newborn ; Apoptosis ; Cell Hypoxia ; Myocardial Reperfusion Injury ; etiology ; metabolism ; Myocytes, Cardiac ; cytology ; metabolism ; Oxidative Stress ; Rats ; Rats, Wistar ; Receptors, Dopamine D2 ; metabolism

OBJECTIVETo explore the role of spinal MAPK-ERK signal pathway in myocardial ischemia-reperfusion (I/R) injury.

METHODSSixty male Sprague-Dawley(SD) rats (80-100 g) were randomly divided into 3 groups: sham (n=10), PD98059 (n=25) and I/R groups (n=25). Three days after successful intrathecal implantation, 5 μg DMSO was injected intrathecally into the sham group, and then the left coronary arteries were separated without being tied. Rats in the I/R and PD98059 groups were injected with 5 μL DMSO and PD98059 (5 μg) 30 minutes before thoractomy respectively. Then the left coronary artery was tied for 30 minutes followed by 120 minutes of reperfusion. After the experiments, the ERK phosphorylation condition of T1-T4 spinal cord segments was detected with immunofluorescence; the myocardiac apoptosic index and infarct size were measured.

RESULTSExpression of p-ERK in the I/R group was significantly higher than in the sham and PD98059 groups (P<0.05). Myocardial apoptotic index and infarct size in the PD98059 group were significantly lower than in the I/R group (P<0.05), but higher in the PD98059 group than in the sham group (P<0.05).

CONCLUSIONSThe MAPK-ERK pathway in the superior thorathic spinal cord can be activated by myocardial ischemia-reperfusion and inhibition of the pathway can play a protective role in myocardial ischemia-reperfusion injury.

Animals ; Apoptosis ; drug effects ; Flavonoids ; pharmacology ; therapeutic use ; MAP Kinase Signaling System ; physiology ; Male ; Myocardial Infarction ; drug therapy ; Myocardial Reperfusion Injury ; etiology ; Rats ; Rats, Sprague-Dawley ; Reperfusion Injury ; Spinal Cord ; physiology