title: Ginsenoside Rg1 inhibits autophagy in H9c2 cardiomyocytes exposed to hypoxia/reoxygenation.
abstract: Ginsenoside Rg1 promotes antioxidative protection and intracellular calcium homeostasis in cardiomyocytes hypoxia/reoxygenation (H/R) model. However, the pharmacological effects of G-Rg1 on autophagy in cardiomyocytes have not been reported. In this study, we employed H9c2 cardiomyocytes as a model to investigate the effects of G-Rg1 on autophagy in cardiomyocytes under H/R stress. Our results showed that H/R induced increased level of LC3B-2, an autophagy marker, in a time-dependent manner in association with decreased cell viability and cellular ATP content. H/R-induced autophagy and apoptosis were further confirmed by morphological examination. 100 μmol/l Rg1-inhibited H/R induced autophagy and apoptosis, and this was associated with the increase of cellular ATP content and the relief of oxidative stress in the cells. Mechanistically, we found that Rg1 inhibited the activation of AMPKα, promoted the activation of mTOR, and decreased the levels of LC3B-2 and Beclin-1. In conclusion, our data suggest that H/R induces autophagy in H9c2 cells leading to cell injury. Rg1 inhibits autophagosomal formation and apoptosis in the cells, which may be beneficial to the survival of cardiomyocytes under H/R.
authors.affiliation: Department of Geriatric, Peking University First Hospital, No. 8, Xishiku Street, Xicheng District, Beijing, 100034, China.
authors.forename: Zi-Long
authors.initials: ZL
authors.lastname: Zhang
authors.forename: Yan
authors.initials: Y
authors.lastname: Fan
authors.forename: Mei-Lin
authors.initials: ML
authors.lastname: Liu
mesh_terms: D000255:Adenosine Triphosphate / Q000378:metabolism; D000263:Adenylate Kinase / Q000378:metabolism; D000818:Animals; D000975:Antioxidants / Q000494:pharmacology*; D017209:Apoptosis; D001343:Autophagy / Q000187:drug effects*; D015687:Cell Hypoxia; D002460:Cell Line; D002470:Cell Survival; D004789:Enzyme Activation / Q000187:drug effects; D036145:Ginsenosides / Q000494:pharmacology*; D008869:Microtubule-Associated Proteins / Q000235:genetics / Q000378:metabolism; D015428:Myocardial Reperfusion Injury / Q000473:pathology; D032383:Myocytes, Cardiac / Q000187:drug effects / Q000473:pathology / Q000502:physiology*; D018384:Oxidative Stress / Q000187:drug effects; D051381:Rats; D015854:Up-Regulation
chemical_list: D000975:Antioxidants; D036145:Ginsenosides; D008869:Microtubule-Associated Proteins; D000255:Adenosine Triphosphate; D000263:Adenylate Kinase; C035054:ginsenoside Rg1