title: Astragaloside IV inhibits doxorubicin-induced cardiomyocyte apoptosis mediated by mitochondrial apoptotic pathway via activating the PI3K/Akt pathway.
abstract: Doxorubicin (DOX) is a widely used antitumor drug whose application is seriously limited by its cardiotoxicity. Mitochondria-mediated cardiomyocyte apoptosis plays a critical role in DOX-induced cardiotoxicity (DIC). The aim of the present study was to investigate the protective effect of astragaloside IV (3-O-beta-D-xylopyranosyl-6-O-beta-D-glucopyranosyl-cycloastragenol, AS-IV), a pure saponin isolated from Astragalus membranaceus, against DOX-induced cardiomyocyte apoptosis in primary cultured neonatal rat cardiomyocytes. Immunocytochemistry and Microculture Tetrazolium (MTT) assays showed that AS-IV significantly reduced DOX-induced cardiomyocyte loss. Additionally, AS-IV markedly ameliorated DOX-caused cardiomyocyte dysfunction via restoring the beating cell ratio and beating rate in cardiomyocytes. Furthermore, AS-IV substantially reduced the mitochondrial reactive oxygen species (ROS) production and lactate dehydrogenase (LDH), creatine kinase-MB isoenzyme (CK-MB) and cytochrome c (CytC) release, and restored the reduced ATP level, succinate dehydrogenase (SDH) and ATP synthase activities induced by DOX, suggesting that AS-IV significantly attenuated DOX-induced mitochondrial damage and dysfunction. It was further observed that DOX-induced cardiomyocyte apoptosis, as qualitatively evaluated by Hoechst 33258 staining and accurately quantified by flow cytometry, was markedly inhibited by AS-IV. Western blot analysis manifested that AS-IV significantly inhibited the activation of mitochondrial apoptotic pathway (MAP) via inducing the phosphorylation of Akt and Bad. Furthermore, phosphatidylinositol 3-kinase (PI3K) inhibitor 2-(4-morpholinyl)-8-phenyl-1(4H)-benzopyran-4-one hydrochloride (LY294002) remarkably inhibited the anti-apoptotic effect of AS-IV. Moreover, AS-IV didn't compromise the antitumor activity of DOX. Taken together, our findings indicate that AS-IV ameliorates DIC, and this beneficial effect appears to be dependent on the activation of the PI3K/Akt pathway. Thus, AS-IV may hold promise as an efficient cardioprotective agent against DIC.
authors.affiliation: Department of Pharmacology, Shenyang Pharmaceutical University.
authors.forename: Yuanyuan
authors.initials: Y
authors.lastname: Jia
authors.forename: Daiying
authors.initials: D
authors.lastname: Zuo
authors.forename: Zengqiang
authors.initials: Z
authors.lastname: Li
authors.forename: Hanmo
authors.initials: H
authors.lastname: Liu
authors.forename: Zhengning
authors.initials: Z
authors.lastname: Dai
authors.forename: Jiayi
authors.initials: J
authors.lastname: Cai
authors.forename: Lili
authors.initials: L
authors.lastname: Pang
authors.forename: Yingliang
authors.initials: Y
authors.lastname: Wu
mesh_terms: D000255:Adenosine Triphosphate / Q000378:metabolism; D000818:Animals; D017209:Apoptosis / Q000187:drug effects*; D002478:Cells, Cultured; D052281:Creatine Kinase, Mitochondrial Form / Q000378:metabolism; D045304:Cytochromes c / Q000378:metabolism; D004317:Doxorubicin / Q000009:adverse effects*; D007770:L-Lactate Dehydrogenase / Q000378:metabolism; D008928:Mitochondria / Q000187:drug effects* / Q000378:metabolism; D025261:Mitochondrial Proton-Translocating ATPases / Q000378:metabolism; D032383:Myocytes, Cardiac / Q000187:drug effects* / Q000378:metabolism; D058539:Phosphatidylinositol 3-Kinase / Q000378:metabolism*; D010766:Phosphorylation / Q000187:drug effects; D051057:Proto-Oncogene Proteins c-akt / Q000378:metabolism*; D051381:Rats; D017382:Reactive Oxygen Species / Q000378:metabolism; D012503:Saponins / Q000494:pharmacology*; D013385:Succinate Dehydrogenase / Q000378:metabolism; D014315:Triterpenes / Q000494:pharmacology*; D051025:bcl-Associated Death Protein / Q000378:metabolism
chemical_list: C494821:Bad protein, rat; D017382:Reactive Oxygen Species; D012503:Saponins; D014315:Triterpenes; D051025:bcl-Associated Death Protein; C052064:astragaloside A; D004317:Doxorubicin; D000255:Adenosine Triphosphate; D045304:Cytochromes c; D007770:L-Lactate Dehydrogenase; D013385:Succinate Dehydrogenase; D058539:Phosphatidylinositol 3-Kinase; D051057:Proto-Oncogene Proteins c-akt; D052281:Creatine Kinase, Mitochondrial Form; D025261:Mitochondrial Proton-Translocating ATPases