Objective: To establish the rat model with myocardial hypoxia/reoxygenation (H/R) injury, and investigate the protective effect of EPO pretreatment on the myocardium. Methods: Sixty male adult Wistar rats were randoml...Objective: To establish the rat model with myocardial hypoxia/reoxygenation (H/R) injury, and investigate the protective effect of EPO pretreatment on the myocardium. Methods: Sixty male adult Wistar rats were randomly divided into 3 groups: control group, H/R group, and EPO group, 20 in each group. The rats in EPO group accepted injection of 5 000 U/kg recombinant human erythropoietin (RHuEPO) through vein, and the other rats accepted the injection of the same volume of saline. Twenty-four hours after the injection, rats in the EPO and H/R groups were put into the hypoxia environment for 12 h and then returned to the normoxic environment for 2 h, and then the samples of blood and myocardium were collected. Serum myocardial enzyme activity, apoptosis, ultrastructure, myocardial MDA contents, EPO receptor (EPOR) expression in cardiac myocytes and cardiac functions were tested. Results: EPOR expression was positive in cardiac myocytes of adult rat according to the result of immunonistochemitry assaying. Compared to those in H/R group, rats in EPO group presented lighter injury of myocardial ultrastructure, the reduction of serum myocardial enzyme activity, inhibition of apoptosis, the better recovery of cardiac functions, and the less production of oxygen-derived free radicals. Conclusion: Adult rat cardiac myocytes could express EPOR, and EPO pretreatment produced protective effects on myocardium with H/R injury.展开更多
BACKGROUND:Disturbance of mitochondrial fi ssion and fusion(termed mitochondrial dynamics)is one of the leading causes of ischemia/reperfusion(I/R)-induced myocardial injury.Previous studies showed that mitochondrial ...BACKGROUND:Disturbance of mitochondrial fi ssion and fusion(termed mitochondrial dynamics)is one of the leading causes of ischemia/reperfusion(I/R)-induced myocardial injury.Previous studies showed that mitochondrial aldehyde dehydrogenase 2(ALDH2)conferred cardioprotective effect against myocardial I/R injury and suppressed I/R-induced excessive mitophagy in cardiomyocytes.However,whether ALDH2 participates in the regulation of mitochondrial dynamics during myocardial I/R injury remains unknown.METHODS:In the present study,we investigated the effect of ALDH2 on mitochondrial dynamics and the underlying mechanisms using the H9c2 cells exposed to hypoxia/reoxygenation(H/R)as an in vitro model of myocardial I/R injury.RESULTS:Cardiomyocyte apoptosis was significantly increased after oxygen-glucose deprivation and reoxygenation(OGD/R),and ALDH2 activation largely decreased the cardiomyocyte apoptosis.Additionally,we found that both ALDH2 activation and overexpression significantly inhibited the increased mitochondrial fission after OGD/R.Furthermore,we found that ALDH2 dominantly suppressed dynamin-related protein 1(Drp1)phosphorylation(Ser616)and adenosine monophosphate-activated protein kinase(AMPK)phosphorylation(Thr172)but not interfered with the expression levels of mitochondrial shaping proteins.CONCLUSIONS:We demonstrate the protective effect of ALDH2 against cardiomyocyte H/R injury with a novel mechanism on mitochondrial fission/fusion.展开更多
Background:Administration of propofol,an intravenous anesthetic with antioxidant property,immediately at the onset of post-ischemic reperfusion(propofol postconditioning,P-PostC) has been shown to confer cardioprotect...Background:Administration of propofol,an intravenous anesthetic with antioxidant property,immediately at the onset of post-ischemic reperfusion(propofol postconditioning,P-PostC) has been shown to confer cardioprotection against ischemia–reperfusion(I/R) injury,while the underlying mechanism remains incompletely understood.The forkhead box O(FoxO) transcription factors are reported to play critical roles in activating cardiomyocyte survival signaling throughout the process of cellular injuries induced by oxidative stress and are also involved in hypoxic postconditioning mediated neuroprotection,however,the role of FoxO in postconditioning mediated protection in the heart and in particular in high glucose condition is unknown.Methods:Rat heart-derived H9c2 cells were exposed to high glucose(HG) for 48 h,then subjected to hypoxia/reoxygenation(H/R,composed of 8 h of hypoxia followed by 12 h of reoxygenation) in the absence or presence of postconditioning with various concentrations of propofol(P-PostC) at the onset of reoxygenation.After having identified the optical concentration of propofol,H9c2 cells were subjected to H/R and P-PostC in the absence or presence of FoxO1 or FoxO3a gene silencing to explore their roles in P-PostC mediated protection against apoptotic and autophagic cell deaths under hyperglycemia.Results:The results showed that HG with or without H/R decreased cell viability,increased lactate dehydrogenase(LDH) leakage and the production of reactive oxygen species(ROS) in H9c2 cells,all of which were significantly reversed by propofol(P-PostC),especially at the concentration of 25 μmol/L(P25)(P<0.05,NC vs.HG;HG vs.HG+HR;HG+HR+P12.5 or HG+HR+P25 or HG+HR+P50 vs.HG+HR).Moreover,we found that propofol(P25) decreased H9c2 cells apoptosis and autophagy that were concomitant with increased FoxO1 and FoxO3a expression(P<0.05,HG+HR+P25 vs.HG+HR).The protective effects of propofol(P25) against H/R injury were reversed by silencing FoxO1 or FoxO3a(P<0.05,HG+HR+P25 vs.HG+HR+P25+siRNA-1 or HG+HR+P25+siRNA-5).Conclusions:It is concluded that propofol postconditioning attenuated H9c2 cardiac cells apoptosis and autophagy induced by H/R injury through upregulating FoxO1 and FoxO3a under hyperglycemia.展开更多
目的探究阿司匹林通过调节铁死亡对氧糖剥夺/复氧(oxygen-glucose deprivation/reoxygenation,OGD/R)诱导的小鼠神经元HT22细胞损伤的作用。方法体外培养小鼠海马神经元HT22细胞,选取HT22细胞分为对照组、模型组、低剂量组、中剂量组、...目的探究阿司匹林通过调节铁死亡对氧糖剥夺/复氧(oxygen-glucose deprivation/reoxygenation,OGD/R)诱导的小鼠神经元HT22细胞损伤的作用。方法体外培养小鼠海马神经元HT22细胞,选取HT22细胞分为对照组、模型组、低剂量组、中剂量组、高剂量组(n=3),除对照组外,其余4组建立OGD/R神经元细胞损伤模型,低、中、高剂量组分别给予阿司匹林100、200、400μg/ml处理。检测各组细胞活力及炎性因子肿瘤坏死因子α(tumor necrosis factor alpha,TNF-α)、白细胞介素(interleukin,IL)1β、IL-6水平;试剂盒检测超氧化物歧化酶、过氧化氢酶、谷胱甘肽、活性氧、乳酸脱氢酶、Fe^(2+)、丙二醛水平;Western blot检测铁死亡相关蛋白溶质载体家族7成员11(solute carrier family 7 members 11,SLC7A11)、谷胱甘肽过氧化物酶4(glutathione peroxidase 4,GPX4)以及酰基辅酶A合成酶长链家族成员4(acyl-coa synthase long chain family member 4,ACSL4)水平。结果模型组细胞活力明显低于对照组,差异有统计学意义(0.49±0.07 vs 1.00±0.12,P<0.01),低、中、高剂量组细胞活力明显高于模型组,差异有统计学意义(0.72±0.10 vs 0.49±0.07,P<0.05;0.87±0.10 vs 0.49±0.07,P<0.01;0.93±0.07 vs 0.49±0.07,P<0.01)。与对照组比较,模型组TNF-α、IL-1β、IL-6、活性氧、乳酸脱氢酶、Fe^(2+)、丙二醛、ACSL4蛋白表达明显升高,超氧化物歧化酶、抗氧化酶、谷胱甘肽、SLC7A11、GPX4蛋白表达明显降低,差异有统计学意义(P<0.01)。与模型组比较,低、中、高剂量组TNF-α、IL-1β、IL-6、活性氧、乳酸脱氢酶Fe^(2+)、丙二醛、ACSL4蛋白表达明显降低,超氧化物歧化酶、抗氧化酶、谷胱甘肽、SLC7A11、GPX4蛋白表达明显升高,差异有统计学意义(P<0.05,P<0.01)。结论阿司匹林可以通过调节铁死亡,减轻OGD/R诱导的小鼠神经元HT22细胞损伤,且呈剂量依赖性。展开更多
文摘Objective: To establish the rat model with myocardial hypoxia/reoxygenation (H/R) injury, and investigate the protective effect of EPO pretreatment on the myocardium. Methods: Sixty male adult Wistar rats were randomly divided into 3 groups: control group, H/R group, and EPO group, 20 in each group. The rats in EPO group accepted injection of 5 000 U/kg recombinant human erythropoietin (RHuEPO) through vein, and the other rats accepted the injection of the same volume of saline. Twenty-four hours after the injection, rats in the EPO and H/R groups were put into the hypoxia environment for 12 h and then returned to the normoxic environment for 2 h, and then the samples of blood and myocardium were collected. Serum myocardial enzyme activity, apoptosis, ultrastructure, myocardial MDA contents, EPO receptor (EPOR) expression in cardiac myocytes and cardiac functions were tested. Results: EPOR expression was positive in cardiac myocytes of adult rat according to the result of immunonistochemitry assaying. Compared to those in H/R group, rats in EPO group presented lighter injury of myocardial ultrastructure, the reduction of serum myocardial enzyme activity, inhibition of apoptosis, the better recovery of cardiac functions, and the less production of oxygen-derived free radicals. Conclusion: Adult rat cardiac myocytes could express EPOR, and EPO pretreatment produced protective effects on myocardium with H/R injury.
基金the National Key R&D Program of China(2017YFC0908700,2017YFC0908703)National Natural Science Foundation of China(81772036,81671952,81873950,81873953,81570401,81571934)+4 种基金National S&T Fundamental Resources Investigation Project(2018FY100600,2018FY100602)Taishan Pandeng Scholar Program of Shandong Province(tspd20181220)Taishan Young Scholar Program of Shandong Province(tsqn20161065,tsqn201812129)Key R&D Program of Shandong Province(2018GSF118003)the Fundamental Research Funds of Shandong University(2018JC011).
文摘BACKGROUND:Disturbance of mitochondrial fi ssion and fusion(termed mitochondrial dynamics)is one of the leading causes of ischemia/reperfusion(I/R)-induced myocardial injury.Previous studies showed that mitochondrial aldehyde dehydrogenase 2(ALDH2)conferred cardioprotective effect against myocardial I/R injury and suppressed I/R-induced excessive mitophagy in cardiomyocytes.However,whether ALDH2 participates in the regulation of mitochondrial dynamics during myocardial I/R injury remains unknown.METHODS:In the present study,we investigated the effect of ALDH2 on mitochondrial dynamics and the underlying mechanisms using the H9c2 cells exposed to hypoxia/reoxygenation(H/R)as an in vitro model of myocardial I/R injury.RESULTS:Cardiomyocyte apoptosis was significantly increased after oxygen-glucose deprivation and reoxygenation(OGD/R),and ALDH2 activation largely decreased the cardiomyocyte apoptosis.Additionally,we found that both ALDH2 activation and overexpression significantly inhibited the increased mitochondrial fission after OGD/R.Furthermore,we found that ALDH2 dominantly suppressed dynamin-related protein 1(Drp1)phosphorylation(Ser616)and adenosine monophosphate-activated protein kinase(AMPK)phosphorylation(Thr172)but not interfered with the expression levels of mitochondrial shaping proteins.CONCLUSIONS:We demonstrate the protective effect of ALDH2 against cardiomyocyte H/R injury with a novel mechanism on mitochondrial fission/fusion.
基金supported by the National Natural Science Foundation of China grant (NSFC81970247)。
文摘Background:Administration of propofol,an intravenous anesthetic with antioxidant property,immediately at the onset of post-ischemic reperfusion(propofol postconditioning,P-PostC) has been shown to confer cardioprotection against ischemia–reperfusion(I/R) injury,while the underlying mechanism remains incompletely understood.The forkhead box O(FoxO) transcription factors are reported to play critical roles in activating cardiomyocyte survival signaling throughout the process of cellular injuries induced by oxidative stress and are also involved in hypoxic postconditioning mediated neuroprotection,however,the role of FoxO in postconditioning mediated protection in the heart and in particular in high glucose condition is unknown.Methods:Rat heart-derived H9c2 cells were exposed to high glucose(HG) for 48 h,then subjected to hypoxia/reoxygenation(H/R,composed of 8 h of hypoxia followed by 12 h of reoxygenation) in the absence or presence of postconditioning with various concentrations of propofol(P-PostC) at the onset of reoxygenation.After having identified the optical concentration of propofol,H9c2 cells were subjected to H/R and P-PostC in the absence or presence of FoxO1 or FoxO3a gene silencing to explore their roles in P-PostC mediated protection against apoptotic and autophagic cell deaths under hyperglycemia.Results:The results showed that HG with or without H/R decreased cell viability,increased lactate dehydrogenase(LDH) leakage and the production of reactive oxygen species(ROS) in H9c2 cells,all of which were significantly reversed by propofol(P-PostC),especially at the concentration of 25 μmol/L(P25)(P<0.05,NC vs.HG;HG vs.HG+HR;HG+HR+P12.5 or HG+HR+P25 or HG+HR+P50 vs.HG+HR).Moreover,we found that propofol(P25) decreased H9c2 cells apoptosis and autophagy that were concomitant with increased FoxO1 and FoxO3a expression(P<0.05,HG+HR+P25 vs.HG+HR).The protective effects of propofol(P25) against H/R injury were reversed by silencing FoxO1 or FoxO3a(P<0.05,HG+HR+P25 vs.HG+HR+P25+siRNA-1 or HG+HR+P25+siRNA-5).Conclusions:It is concluded that propofol postconditioning attenuated H9c2 cardiac cells apoptosis and autophagy induced by H/R injury through upregulating FoxO1 and FoxO3a under hyperglycemia.
文摘目的探究阿司匹林通过调节铁死亡对氧糖剥夺/复氧(oxygen-glucose deprivation/reoxygenation,OGD/R)诱导的小鼠神经元HT22细胞损伤的作用。方法体外培养小鼠海马神经元HT22细胞,选取HT22细胞分为对照组、模型组、低剂量组、中剂量组、高剂量组(n=3),除对照组外,其余4组建立OGD/R神经元细胞损伤模型,低、中、高剂量组分别给予阿司匹林100、200、400μg/ml处理。检测各组细胞活力及炎性因子肿瘤坏死因子α(tumor necrosis factor alpha,TNF-α)、白细胞介素(interleukin,IL)1β、IL-6水平;试剂盒检测超氧化物歧化酶、过氧化氢酶、谷胱甘肽、活性氧、乳酸脱氢酶、Fe^(2+)、丙二醛水平;Western blot检测铁死亡相关蛋白溶质载体家族7成员11(solute carrier family 7 members 11,SLC7A11)、谷胱甘肽过氧化物酶4(glutathione peroxidase 4,GPX4)以及酰基辅酶A合成酶长链家族成员4(acyl-coa synthase long chain family member 4,ACSL4)水平。结果模型组细胞活力明显低于对照组,差异有统计学意义(0.49±0.07 vs 1.00±0.12,P<0.01),低、中、高剂量组细胞活力明显高于模型组,差异有统计学意义(0.72±0.10 vs 0.49±0.07,P<0.05;0.87±0.10 vs 0.49±0.07,P<0.01;0.93±0.07 vs 0.49±0.07,P<0.01)。与对照组比较,模型组TNF-α、IL-1β、IL-6、活性氧、乳酸脱氢酶、Fe^(2+)、丙二醛、ACSL4蛋白表达明显升高,超氧化物歧化酶、抗氧化酶、谷胱甘肽、SLC7A11、GPX4蛋白表达明显降低,差异有统计学意义(P<0.01)。与模型组比较,低、中、高剂量组TNF-α、IL-1β、IL-6、活性氧、乳酸脱氢酶Fe^(2+)、丙二醛、ACSL4蛋白表达明显降低,超氧化物歧化酶、抗氧化酶、谷胱甘肽、SLC7A11、GPX4蛋白表达明显升高,差异有统计学意义(P<0.05,P<0.01)。结论阿司匹林可以通过调节铁死亡,减轻OGD/R诱导的小鼠神经元HT22细胞损伤,且呈剂量依赖性。
