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Objective:To explore the regulatory effect of cellular FLICE-like inhibitory protein (cFLIP) on myocardial ischemia-reperfusion injury based on the RIPK1/RIPK3/MLKL-mediated necroptosis pathway.Methods:The cardiomyocyte hypoxia/reoxygenation (H/R) model was constructed by hypoxia for 4 h/reoxygenation for 12 h, and the rat ischemia reperfusion (I/R) model was constructed by ligating the left anterior descending artery for 30 min and reperfusion for 3 h. CCK-8 method was used to detect the viability of cardiomyocytes in each group. DAPI/PI double staining was used to observe changes in necrosis rate of myocardial cell. STRING database was used to predict the protein interaction network of cFLIP. TTC staining was used to detect the area of myocardial infarction in each group of rats, and the protein expression of cFLIPL, cFLIPS, p-RIPK1, p-RIPK3 and p-MLKL were detected by Western blot.Results:In cardiomyocyte H/R injury and myocardial tissue I/R injury, the protein expressions of cFLIPL and cFLIPS were significantly down-regulated, while the levels of p-RIPK1, p-RIPK3 and p-MLKL were increased significantly. Up-regulating the protein expression of cFLIPL and cFLIPS could significantly reduce the damage of cardiomyocytes and the rate of cell necrosis induced by H/R, and decrease the area of myocardial infarction caused by I/R. STRING database results showed that cFLIP had direct protein interactions with RIPK1 and RIPK3. Overexpression of cFLIP in cardiomyocyte and myocardial tissue significantly inhibited H/R or I/R induced the phosphorylation levels of RIPK1, RIPK3 and MLKL.Conclusions:Overexpression of cFLIP can significantly inhibit the RIPK1/RIPK3/MLKL-mediated necroptosis, thereby reducing myocardial cell damage and decreasing the area of myocardial infarction.
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OBJECTIVE：To syst ematically evaluate the effectiveness and safety of ticagrelor versus clopidogrel in the treatment of acute coronary syndrome （ACS）patients in East Asia ，and to provide evidence-based references for clinical drug use. METHODS：Retrieved from Cochrane Library ，PubMed，Embase，CNKI，Wanfang database ，etc.，randomized controlled trials （RCTs）about ticagrelor （trial group ）versus clopidogrel （control group ）in the treatment of ACS patients in east Asia were collected. After literature screening and data extraction ，the quality of included literatures was evaluated by using biasrisk evaluation tool recommended by Co chrane system evaluation manual 5.1.0，and Meta-analysis was performed by using Rev Man 5.3 statistical software. RESULTS ：A total of 5 RCTs were included ，with a total of 4 511 cases. Meta-analysis showed that the incidence of major adverse cardiovascular events [OR ＝0.85，95％CI（0.68，1.04），P＝0.12]，the incidence of death from cardiovascular causes [OR ＝0.76，95％CI（0.57，1.03），P＝0.08] and the incidence of stroke [OR ＝0.77，95％CI（0.48，1.24），P＝0.28]， without statistical significance. The incidence of major bleeding events [OR ＝1.54，95％CI（1.19，1.99），P＝0.001] and minor bleeding events [OR ＝1.80，95％ CI（1.40，2.32），P＜0.000 01] in trial group were significantly higher than control group. CONCLUSIONS：Ticagrelor is comparable to clopidogrel in reduce the major adverse cardiovascular events，death from cardiovascular causes and stroke in ACS patients in East Asian ，but it can increase the risk of major and minor bleeding events.
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Objective To investigate the association of rs1412125 at high-mobility group box 1 (HMGB1) gene with atrial fibrillation (AF) in Chinese Han population. Methods 396 patients with AF and 726 control subjects were recruited to this study. A case-control association analysis was applied to assess the as-sociation between rs1412125 in HMGB1 and AF. Results There were no significant differences in rs1412125 and the frequency of genotype distribution between the study group and the control group (allelic association:object P value was 1.05E-06, adjust P value was 0.176; genotypic association: additive P value was 0.146, dominant P value was 0.162, and recessive P value was 0.998). The interactions analysis showed that rs1412125 allele C increased the risk of AF in male subjects with rheumatic heart disease (adjust P value was 2.07E-04, rectify OR = 8.20, and 95%CI: 2.70-25.0). Conclusions There is no independent genetic association between rs1412125 at HMGB1 and atrial fibrillation. However , the interactions between rs1412125 and both gender and rheumatic heart disease might increase the risk of atrial fibrillation.
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BACKGROUND:Ischemia/reperfusion injury can cause the necrosis of cardiomyocyte,and it can also induce cell apoptosis.However,cell apoptosis may be the main death type of cardiomyocyte at the early stage of infarction,and it may be one of causes for expanding myocardial infarction area.OBJECTIVE:The goal of this study was to observe the anti-apoptotic effect of adenosine (ADO) preconditioning on cardiomyocytes during the ischemia/reperfusion,and to investigate the role of apoptosis-related gene protein Bcl-2 and Bax.DESIGN:A randomized controlled animal experiment.SETTING:First College of Clinical Medical Science,China Three Gorges University&Department of Cardiology,Yichang Central People's Hospital.MATERIALS:Thirty-six healthy male rabbits of clean grade,weighing 2.5 to 3.0 kg,were provided by Laboratory Animal Department,Tongji Medical College,Huazhong University of Science and Technology.The protocol was carried out in accordance with animal ethics guidelines for the use and care of animals.All rabbits were divided into 3 groups according to random number table.There were 12 animals in either control,ADO or ADO+DPCPX (an adenosine A1 receptor antagonist).METHODS:This experiment was carried out in the Central Laboratory,China Three Gorges University between October 2005 and October 2006.Ex vivo rabbit myocardial ischemia/reperfusion models were prepared.After being anesthetized,the rabbits were performed anticoagulation with heparin and carried out Langendorff retroperfusion.In the control group,the hearts of animals subjected to 40 minutes of ischemia and 60 minutes of reperfusion.Six of them were used for determining myocardial infarct size after reperfusion,another six for cardiomyocyte apoptosis,gene expression and ultrastructural analysis of myocardium.In the ADO group:The ADO hearts were continuously infused with 10 μmol/L of adenosine 30 minutes before ischemia,and operated according to the requirement of control group.In the DPCPX roup:the isolated hearts of animals were infused for 15 minutes with 10 mmol/L of DPCPX 45 minutes before ischemia.and operated in accordance with ADO group.MAIN OUTCOME MEASURES:①The heart rate and blood pressure of animals in 3 groups were measured during ischemia/reperfusion process.②The infarct size was determined by triphenyltetrazolium chloride(TTC) staining.③The apoptotic index of cardiomyocytes was detected by histological TUNEL staining and DNA ladder on agarose gel electrophoresis.④Apoptosis-related protein Bcl-2 and Bax expressions were detected by in situ immunohistochemical staining.RESULTS:Thirty-six rabbits were enrolled in the final analysis.①Comparison of heart rate and blood pressure:During the process of ischemia/reperfusion,both heart rate and blood pressure were persistently decreased significantly (P＜0.01).There were no significant differences in two indexes between any two groups (P＞0.05).②Comparison of myocardial infarct size:There were no significant differences in myocardial infarct size among the control group,ADO group and DPCPX group (P＞0.05).The myocardial infarct size of rabbits in the ADO group was significantly smaller than that in the control group.It suggested that ADO preconditioning could contract the myocardial infarct size of rabbits.The myocardial infarct size of rabbits in the ADO+DPCPX group was significantly larger than that in the ADO group,but significantly smaller than that in the control group (P＜0.01).It suggested that DPCPX could partially inhibit the protective effect of ADO.③Comparison of apoptosis of cardiomyocytes: Apoptotic cells were not found in the non-ischemic myocardial tissue,but found in the infarct tissue and infarct edge ischemic tissue.Apoptotic cells in the control group and ADO+DPCPX group were significantly more than those in the ADO group.Apoptotic index in the control group and ADO+DPCPX group was significantly higher than that in the control group,respectively (P＜0.01).④Comparison of apoptosis-related protein expression:The absorbance of Bax in the ADO group was significantly lower than that in the control group(P＜0.01).The absorbance of Bax in the ADO+DPCPX group was significantly lower than that in the control group,but significantly higher than that in the ADO group (P＜0.01).The value of Bcl-2/Bax in the control group was significantly lower than that in the ADO group (P＜0.01).The value of Bcl-2/Bax in the ADO+DPCPX group was significantly higher than that in the control group,but significantly higher than that in the ADO group(P＜0.01).CONCLUSION:Exogenous ADO inhiblts reperfusion-induced apoptosis of cardiomyocytes,which is partially mediated by DPCPX:Down-regulation of apoptosis-related Bax protein plays an important role in the anti-apoptotic effect of exogenous ADO.
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Objective To investigate the effect of Tenascin-C on remodeling of ventricle in mice with chronic autoimmune myocarditis.Methods Seventy-five specific pathogen-free BALB/c mice were divided into experimental group(n=45)and control group(n=30).Animals in experimental group were immunized with an emulsion of polypeptides(myhc-? 614-629)and complete Freund's adjuvant(CFA)on day 1 and day 8,while those in control group with equal volume of mixture of phosphate buffer solution(PBS)and CFA.Groups of mice were sacrificed respectively on day 21,day 75 and day 120 after the first immunization.Hematoxylin and eosin(H-E)staining was used to identify the areas of inflammation,and Masson staining was used to identify the areas of fibrosis.The Tenascin-C protein expression in myocardium was detected by Western blotting.The content of serum procollagen type-Ⅲ amino-terminal propeptide(PⅢNP)was measured by radioimmunoassay.The correlation between Tenascin-C protein expression and content of serum PⅢNP was analyzed.Results On day 21,inflammatory infiltration in the myocardium was remarkable,with slight deposition of collagen in the interstitial tissue.On day 75 and day 120,inflammatory infiltration in myocardium was markedly reduced,but with more marked deposition of collagen.The Tenascin-C protein expression in myocardium and the content of serum PⅢNP were significantly higher in experimental group than in control group(P