title: Icariside II, a novel phosphodiesterase 5 inhibitor, protects against H2O2-induced PC12 cells death by inhibiting mitochondria-mediated autophagy.
abstract: Oxidative stress is a major cause of cellular injury in a variety of human diseases including neurodegenerative disorders. Thus, removal of excessive reactive oxygen species (ROS) or suppression of ROS generation may be effective in preventing oxidative stress-induced cell death. This study was designed to investigate the effect of icariside II (ICS II), a novel phosphodiesterase 5 inhibitor, on hydrogen peroxide (H2O2)-induced death of highly differentiated rat neuronal PC12 cells, and to further examine the underlying mechanisms. We found that ICS II pre-treatment significantly abrogated H2O2-induced PC12 cell death as demonstrated by the increase of the number of metabolically active cells and decrease of intracellular lactate dehydrogenase (LDH) release. Furthermore, ICS II inhibited H2O2-induced cell death through attenuating intracellular ROS production, mitochondrial impairment, and activating glycogen synthase kinase-3β (GSK-3β) as demonstrated by reduced intracellular and mitochondrial ROS levels, restored mitochondrial membrane potential (MMP), decreased p-tyr216-GSK-3β level and increased p-ser9-GSK-3β level respectively. The GSK-3β inhibitor SB216763 abrogated H2O2-induced cell death. Moreover, ICS II significantly inhibited H2O2-induced autophagy by the reducing autophagosomes number and the LC3-II/LC3-I ratio, down-regulating Beclin-1 expression, and up-regulating p62/SQSTM1 and HSP60 expression. The autophagy inhibitor 3-methyl adenine (3-MA) blocked H2O2-induced cell death. Altogether, this study demonstrated that ICS II may alleviate oxidative stress-induced autophagy in PC12 cells, and the underlying mechanisms are related to its antioxidant activity functioning via ROS/GSK-3β/mitochondrial signalling pathways.
authors.affiliation: School of Pharmacy, Zunyi Medical University, Guizhou, China.
authors.forename: Jianmei
authors.initials: J
authors.lastname: Gao
authors.affiliation: Department of Pharmacology and Key Laboratory of Basic Pharmacology of Ministry of Education, Zunyi Medical University, Guizhou, China.
authors.forename: Yuanyuan
authors.initials: Y
authors.lastname: Deng
authors.affiliation: Department of Pharmacology and Key Laboratory of Basic Pharmacology of Ministry of Education, Zunyi Medical University, Guizhou, China.
authors.forename: Caixia
authors.initials: C
authors.lastname: Yin
authors.affiliation: Department of Pharmacology and Key Laboratory of Basic Pharmacology of Ministry of Education, Zunyi Medical University, Guizhou, China.
authors.forename: Yuangui
authors.initials: Y
authors.lastname: Liu
authors.affiliation: Department of Pharmacology and Key Laboratory of Basic Pharmacology of Ministry of Education, Zunyi Medical University, Guizhou, China.
authors.forename: Wei
authors.initials: W
authors.lastname: Zhang
authors.affiliation: Department of Pharmacology and Key Laboratory of Basic Pharmacology of Ministry of Education, Zunyi Medical University, Guizhou, China.
authors.forename: Jingshan
authors.initials: J
authors.lastname: Shi
authors.affiliation: Department of Pharmacology and Key Laboratory of Basic Pharmacology of Ministry of Education, Zunyi Medical University, Guizhou, China.
authors.forename: Qihai
authors.initials: Q
authors.lastname: Gong
mesh_terms: D000818:Animals; D017209:Apoptosis / Q000187:drug effects*; D000071182:Autophagosomes / Q000187:drug effects / Q000378:metabolism; D001343:Autophagy / Q000187:drug effects*; D000242:Cyclic AMP / Q000378:metabolism; D006152:Cyclic GMP / Q000378:metabolism; D019610:Cytoprotection / Q000187:drug effects*; D005419:Flavonoids / Q000737:chemistry / Q000494:pharmacology*; D000071679:Glycogen Synthase Kinase 3 beta / Q000378:metabolism; D006861:Hydrogen Peroxide / Q000633:toxicity*; D042541:Intracellular Space / Q000378:metabolism; D053078:Membrane Potential, Mitochondrial / Q000187:drug effects; D008928:Mitochondria / Q000187:drug effects / Q000378:metabolism*; D008954:Models, Biological; D009569:Nitric Oxide / Q000378:metabolism; D016716:PC12 Cells; D058986:Phosphodiesterase 5 Inhibitors / Q000737:chemistry / Q000494:pharmacology*; D051381:Rats
chemical_list: D005419:Flavonoids; D058986:Phosphodiesterase 5 Inhibitors; C060988:baohuoside I; D009569:Nitric Oxide; D006861:Hydrogen Peroxide; D000242:Cyclic AMP; D000071679:Glycogen Synthase Kinase 3 beta; D006152:Cyclic GMP
keywords: autophagy; glycogen synthase kinase-3β; icariside II; mitochondria; reactive oxygen species