OBJECTIVE In this study we explored the role of Epac1-Rap1 pathway in the acute myocardial ischemia/reperfusion injury(MIRI) in vitro and in vivo.METHODS An acute myocardial ischemia/reperfusion injury model was estab...OBJECTIVE In this study we explored the role of Epac1-Rap1 pathway in the acute myocardial ischemia/reperfusion injury(MIRI) in vitro and in vivo.METHODS An acute myocardial ischemia/reperfusion injury model was established by the ligation of left anterior descending coronary.Myocardial architecture,fibers and apoptosis was evaluated by the Masson trichrome staining,Sirius red staining and TUNEL assay.H9c2 cells were subjected to hypoxia for 5 h followed by 1-h reoxygen.ation in vitro.Cell viability was measured by MTT assay and cellular injury was evaluated by measuring the release of lactate dehydrogenase(LDH).Western blot,real-time PCR and immunofluorescence were used to detect the expressions of Epac1 and relative downstream molecules.RESULTS Myocardial IR-induced cardiac apoptosis and accumulation of Epac1 and Rap1 in rat IR injury model.Direct Epac activation by 8-CPT(8-(4-chlorophenylthio)-2′-O-methyl-cAMP) exacerbated cardiomyocyte death and dysfunction following hypoxia-reoxygenation(H/R),selective activation of Epac in response to H/R was evident which enriched for cytosolic/membrane proteins and mRNA.Harmacological inhibitor of Epac(ESI-09) significantly ameliorated myocardial injury with the decline of Epac expression.Epac inhibitor and agonist studies also implicated the effect of Rap1,which is downstream of Epac in this pathway.The expression of Rap1 elevated when activated by Epac agonist and was blocked by Epac inhibitor.The same result was true for myocyte CaMK-II and intracellular calcium ions activation.Moreover,ESI-09 also increased ERK1/2 phosphorylation.CONCLUSION Our study reveal that Epac1/Rap1 signaling pathway is involved in the pathogenesis of myocardial I/R injury in rats,which provides evidence on the development of therapeutic strategies target this pathway for myocardial I/R injury.展开更多
Objectives: To investigate the protective effects of Shexiang Tongxin Dropping Pill(麝香通心滴丸,STP) on Na2S2O4-induced hypoxia-reoxygenation injury in cardiomyoblast H9c2 cells. Methods: The cell viability and level...Objectives: To investigate the protective effects of Shexiang Tongxin Dropping Pill(麝香通心滴丸,STP) on Na2S2O4-induced hypoxia-reoxygenation injury in cardiomyoblast H9c2 cells. Methods: The cell viability and levels of mRNA and protein expression in H9c2 cells were determined following Na2S2O4-induced hypoxia using Hoechst staining, annexin V/propidium iodide(PI) flow cytometry, real-time polymerase chain reaction and Western blot analysis. Results: STP pretreatment signi?cantly increased the viability and inhibited aberrant morphological changes in H9c2 cardiomyoblast cells induced by Na2S2O4 treatment(P<0.05). In addition, STP pretreatment attenuated Na2S2O4-induced hypoxic damage, down-regulated the expression of pro-apoptotic Bax,and up-regulated the expression of anti-apoptotic Bcl-2 in H9c2 cells(P<0.05). Conclusions: STP was strongly cardioprotective in hypoxia-reoxygenation injury by preventing hypoxic damage and inhibiting cellular apoptosis.These results further support the use of STP as an effective drug for the treatment of ischemic heart disease.展开更多
基金This work supported by the National Natural Science Foundation of China (81470432) and Natural Science Foundation of Anhui Province Education Department (KJ2016A357).
文摘OBJECTIVE In this study we explored the role of Epac1-Rap1 pathway in the acute myocardial ischemia/reperfusion injury(MIRI) in vitro and in vivo.METHODS An acute myocardial ischemia/reperfusion injury model was established by the ligation of left anterior descending coronary.Myocardial architecture,fibers and apoptosis was evaluated by the Masson trichrome staining,Sirius red staining and TUNEL assay.H9c2 cells were subjected to hypoxia for 5 h followed by 1-h reoxygen.ation in vitro.Cell viability was measured by MTT assay and cellular injury was evaluated by measuring the release of lactate dehydrogenase(LDH).Western blot,real-time PCR and immunofluorescence were used to detect the expressions of Epac1 and relative downstream molecules.RESULTS Myocardial IR-induced cardiac apoptosis and accumulation of Epac1 and Rap1 in rat IR injury model.Direct Epac activation by 8-CPT(8-(4-chlorophenylthio)-2′-O-methyl-cAMP) exacerbated cardiomyocyte death and dysfunction following hypoxia-reoxygenation(H/R),selective activation of Epac in response to H/R was evident which enriched for cytosolic/membrane proteins and mRNA.Harmacological inhibitor of Epac(ESI-09) significantly ameliorated myocardial injury with the decline of Epac expression.Epac inhibitor and agonist studies also implicated the effect of Rap1,which is downstream of Epac in this pathway.The expression of Rap1 elevated when activated by Epac agonist and was blocked by Epac inhibitor.The same result was true for myocyte CaMK-II and intracellular calcium ions activation.Moreover,ESI-09 also increased ERK1/2 phosphorylation.CONCLUSION Our study reveal that Epac1/Rap1 signaling pathway is involved in the pathogenesis of myocardial I/R injury in rats,which provides evidence on the development of therapeutic strategies target this pathway for myocardial I/R injury.
基金Supported by the Foundation of Fujian University of Traditional Chinese Medicine(No.X2013026)the Developmental Fund of Chen Ke-ji Integrative Medicine(No.CKJ2013016)the Education Department of Fujian Province(No.JA14163)
文摘Objectives: To investigate the protective effects of Shexiang Tongxin Dropping Pill(麝香通心滴丸,STP) on Na2S2O4-induced hypoxia-reoxygenation injury in cardiomyoblast H9c2 cells. Methods: The cell viability and levels of mRNA and protein expression in H9c2 cells were determined following Na2S2O4-induced hypoxia using Hoechst staining, annexin V/propidium iodide(PI) flow cytometry, real-time polymerase chain reaction and Western blot analysis. Results: STP pretreatment signi?cantly increased the viability and inhibited aberrant morphological changes in H9c2 cardiomyoblast cells induced by Na2S2O4 treatment(P<0.05). In addition, STP pretreatment attenuated Na2S2O4-induced hypoxic damage, down-regulated the expression of pro-apoptotic Bax,and up-regulated the expression of anti-apoptotic Bcl-2 in H9c2 cells(P<0.05). Conclusions: STP was strongly cardioprotective in hypoxia-reoxygenation injury by preventing hypoxic damage and inhibiting cellular apoptosis.These results further support the use of STP as an effective drug for the treatment of ischemic heart disease.
