Hearts of pressure-verload hypertrophy show an increased activation of intracardiac renin-angiotensin system which may contribute to ischemia and reperfusion injury. The purpose of this study is to evaluate whether th...Hearts of pressure-verload hypertrophy show an increased activation of intracardiac renin-angiotensin system which may contribute to ischemia and reperfusion injury. The purpose of this study is to evaluate whether the hypertrophied myocardium is more vulnerable to ischemia and reperfusion injury and to find out its relation to the cardiac renin-ngiotensin system. Hypertrophied rat hearts induced by abdominal aortic banding for 6 weeks were subjected to 2 hours of hypothermic ischemic arrest followed by 30 minutes of reperfusion, and their cardiac function recovery was compared with that of sham-operated normal control hearts. The cardiac renin activity and angiotensin Ⅱ content before ischemia and after reperfusion were determined. It was found that both the pre-schemic renin activity and angiotensin Ⅱ level were higher in hypertrophied myocardium than those in the control: ischemia and reperfusion injury increased both renin activity and angiotensin Ⅱ content in the two groups, but the renin展开更多
Apoptosis is an important programmed cell death process involved in ischemia/reperfusion injury.MicroRNAs are considered to play an important role in the molecular mechanism underlying the regulation of cerebral ische...Apoptosis is an important programmed cell death process involved in ischemia/reperfusion injury.MicroRNAs are considered to play an important role in the molecular mechanism underlying the regulation of cerebral ischemia and reperfusion injury.However,whether miR-670 can regulate cell growth and death in cerebral ischemia/reperfusion and the underlying mechanism are poorly understood.In this study,we established mouse models of transient middle artery occlusion and Neuro 2a cell models of oxygen-glucose deprivation and reoxygenation to investigate the potential molecular mechanism by which miR-670 exhibits its effects during cerebral ischemia/reperfusion injury both in vitro and in vivo.Our results showed that after ischemia/reperfusion injury,miR-670 expression was obviously increased.After miR-670 expression was inhibited with an miR-670 antagomir,cerebral ischemia/reperfusion injury-induced neuronal death was obviously reduced.When miR-670 overexpression was induced by an miR-670 agomir,neuronal apoptosis was increased.In addition,we also found that miR-670 could promote Yap degradation via phosphorylation and worsen neuronal apoptosis and neurological deficits.Inhibition of miR-670 reduced neurological impairments after cerebral ischemia/reperfusion injury.These results suggest that microRNA-670 aggravates cerebral ischemia/reperfusion injury through the Yap pathway,which may be a potential target for treatment of cerebral ischemia/reperfusion injury.The present study was approved by the Institutional Animal Care and Use Committee of China Medical University on February 27,2017(IRB No.2017PS035K).展开更多
Objective:To study the protective mechanism of Chinese medicine Suxiao Jiuxin Pills(速效救心丸,SXJ)on myocardial ischemia and reperfusion(I/R)injury.Methods:Mouse myocardial I/R injury model was created by 30-min coro...Objective:To study the protective mechanism of Chinese medicine Suxiao Jiuxin Pills(速效救心丸,SXJ)on myocardial ischemia and reperfusion(I/R)injury.Methods:Mouse myocardial I/R injury model was created by 30-min coronary artery occlusion followed by 24-h reperfusion,the mice were then divided into the sham group(n=7),the I/R group(n=13),the tirofiban group(TIR,positive drug treatment,n=9),and the SXJ group(n=11).Infarct size(IS),risk region(RR),and left ventricle(LV)were analyzed with double staining methods.In addition,H9C2 rat cardiomyocytes were cultured with Na2S2O4 to simulate I/R in vitro.The phosphorylation of extracellular regulated protein kinases1/2(ERK1/2),protein kinase B(AKT),glycogen synthase kinase-3β(GSK3β),and protein expression of GATA4 in nucleus were detected with Western blot assay.Results:The ratio of IS/RR in SXJ and TIR groups were lower than that in I/R group(SXJ,22.4%±6.6%;TIR,20.8%±3.3%;vs.I/R,35.4%±3.7%,P<0.05,respectively).In vitro experiments showed that SXJ increased the Na2S2O4-enhanced phosphorylation of AKT/GSK3βand nuclear expression of GATA4.Conclusion:SXJ prevents myocardial I/R injury in mice by activating AKT/GSK3βand GATA4 signaling pathways.展开更多
文摘Hearts of pressure-verload hypertrophy show an increased activation of intracardiac renin-angiotensin system which may contribute to ischemia and reperfusion injury. The purpose of this study is to evaluate whether the hypertrophied myocardium is more vulnerable to ischemia and reperfusion injury and to find out its relation to the cardiac renin-ngiotensin system. Hypertrophied rat hearts induced by abdominal aortic banding for 6 weeks were subjected to 2 hours of hypothermic ischemic arrest followed by 30 minutes of reperfusion, and their cardiac function recovery was compared with that of sham-operated normal control hearts. The cardiac renin activity and angiotensin Ⅱ content before ischemia and after reperfusion were determined. It was found that both the pre-schemic renin activity and angiotensin Ⅱ level were higher in hypertrophied myocardium than those in the control: ischemia and reperfusion injury increased both renin activity and angiotensin Ⅱ content in the two groups, but the renin
基金supported by the National Natural Science Foundation of China,Nos.81771271(to JF),81902537(to MJY),82001475(to SJY)a Scientific Fund of Shengjing Hospital of China Medical University,No.M0124(to SJY)+1 种基金the“345 Talent Project”from Shengjing Hospital of China Medical University(to SJY)the Natural Science Foundation of Liaoning Province of China,No.20180550913(to MJY).
文摘Apoptosis is an important programmed cell death process involved in ischemia/reperfusion injury.MicroRNAs are considered to play an important role in the molecular mechanism underlying the regulation of cerebral ischemia and reperfusion injury.However,whether miR-670 can regulate cell growth and death in cerebral ischemia/reperfusion and the underlying mechanism are poorly understood.In this study,we established mouse models of transient middle artery occlusion and Neuro 2a cell models of oxygen-glucose deprivation and reoxygenation to investigate the potential molecular mechanism by which miR-670 exhibits its effects during cerebral ischemia/reperfusion injury both in vitro and in vivo.Our results showed that after ischemia/reperfusion injury,miR-670 expression was obviously increased.After miR-670 expression was inhibited with an miR-670 antagomir,cerebral ischemia/reperfusion injury-induced neuronal death was obviously reduced.When miR-670 overexpression was induced by an miR-670 agomir,neuronal apoptosis was increased.In addition,we also found that miR-670 could promote Yap degradation via phosphorylation and worsen neuronal apoptosis and neurological deficits.Inhibition of miR-670 reduced neurological impairments after cerebral ischemia/reperfusion injury.These results suggest that microRNA-670 aggravates cerebral ischemia/reperfusion injury through the Yap pathway,which may be a potential target for treatment of cerebral ischemia/reperfusion injury.The present study was approved by the Institutional Animal Care and Use Committee of China Medical University on February 27,2017(IRB No.2017PS035K).
基金Supported by the National Natural Science Foundation of China(No.81473471 and No.81603429)Foundation of Guangdong Hospital of Chinese Medicine(No.YK2013B2N11,No.YN2014ZH01,No.YN2014ZHR203,and No.YN2016QJ19)。
文摘Objective:To study the protective mechanism of Chinese medicine Suxiao Jiuxin Pills(速效救心丸,SXJ)on myocardial ischemia and reperfusion(I/R)injury.Methods:Mouse myocardial I/R injury model was created by 30-min coronary artery occlusion followed by 24-h reperfusion,the mice were then divided into the sham group(n=7),the I/R group(n=13),the tirofiban group(TIR,positive drug treatment,n=9),and the SXJ group(n=11).Infarct size(IS),risk region(RR),and left ventricle(LV)were analyzed with double staining methods.In addition,H9C2 rat cardiomyocytes were cultured with Na2S2O4 to simulate I/R in vitro.The phosphorylation of extracellular regulated protein kinases1/2(ERK1/2),protein kinase B(AKT),glycogen synthase kinase-3β(GSK3β),and protein expression of GATA4 in nucleus were detected with Western blot assay.Results:The ratio of IS/RR in SXJ and TIR groups were lower than that in I/R group(SXJ,22.4%±6.6%;TIR,20.8%±3.3%;vs.I/R,35.4%±3.7%,P<0.05,respectively).In vitro experiments showed that SXJ increased the Na2S2O4-enhanced phosphorylation of AKT/GSK3βand nuclear expression of GATA4.Conclusion:SXJ prevents myocardial I/R injury in mice by activating AKT/GSK3βand GATA4 signaling pathways.
