title: Sulfiredoxin-1 exerts anti-apoptotic and neuroprotective effects against oxidative stress-induced injury in rat cortical astrocytes following exposure to oxygen-glucose deprivation and hydrogen peroxide.
abstract: Sulfiredoxin 1 (Srxn1), an endogenous antioxidant protein, plays an important neuroprotective role in cerebral ischemia. However, the exact mechanisms of action of Srxn1 in cerebral ischemia have not yet been fully elucidated. Therefore, in the present study, rat primary cortical astrocytes transfected with a lentiviral vector encoding short hairpin RNA (shRNA) were exposed to oxygen-glucose deprivation (OGD) for 4 h or to 100 µM hydrogen peroxide (H2O2) for 6 h, in order to construct an in vitro model of cerebral ischemia-induced damage. We found that following exposure to OGD or H2O2, the knockdown of Srxn1 resulted in a decrease in cell viability, as shown by MTS assay, an increase in cell damage, as shown by lactate dehydrogenase assay and an increase in cellular apoptosis, as shown by Hoechst 33342 staining and flow cytometry. Furthermore, we found that following exposure to OGD or H2O2, the knockdown of Srxn1 resulted in a decrease in mitochondrial transmembrane potential (Δψm) as indicated by JC-1 staining, an increase in the cytoplasmic expression of cytochrome c (Cyt.C), caspase-3, caspase-9, poly(ADP-ribose) polymerase (PARP) and Bax protein at the protein level, but a decrease in the expression of the anti-apoptotic Bcl-2 protein; these effects were tightly associated with the mitochondrial apoptotic pathway. However, we found that there was no obvious change in the intracellular calcium ([Ca2+]i) levels and caspase-12 expression following the knockdown of Srxn1. Taken together, the results from the present study demonstrate that Srxn1 protects primary rat cortical astrocytes from OGD- or H2O2-induced apoptosis and that involves the activation of the mitochondrial apoptotic pathway, which suggests that Srxn1 may be a potential target in the treatment of cerebral ischemia.
authors.affiliation: Department of Pathology, Chongqing Medical University, Chongqing 400016, P.R. China.
authors.forename: Yunchuan
authors.initials: Y
authors.lastname: Zhou
authors.affiliation: Department of Pathology, Chongqing Medical University, Chongqing 400016, P.R. China.
authors.forename: Yang
authors.initials: Y
authors.lastname: Zhou
authors.affiliation: Department of Pathology, Chongqing Medical University, Chongqing 400016, P.R. China.
authors.forename: Shanshan
authors.initials: S
authors.lastname: Yu
authors.affiliation: Department of Pathology, Chongqing Medical University, Chongqing 400016, P.R. China.
authors.forename: Jingxian
authors.initials: J
authors.lastname: Wu
authors.affiliation: Department of Pathology, Chongqing Medical University, Chongqing 400016, P.R. China.
authors.forename: Yanlin
authors.initials: Y
authors.lastname: Chen
authors.affiliation: Department of Pathology, Chongqing Medical University, Chongqing 400016, P.R. China.
authors.forename: Yong
authors.initials: Y
authors.lastname: Zhao
mesh_terms: D000818:Animals; D017209:Apoptosis / Q000502:physiology*; D051017:Apoptosis Regulatory Proteins / Q000235:genetics*; D001253:Astrocytes / Q000378:metabolism; D002545:Brain Ischemia / Q000503:physiopathology*; D053454:Caspase 12 / Q000096:biosynthesis; D053148:Caspase 3 / Q000096:biosynthesis; D053453:Caspase 9 / Q000096:biosynthesis; D015687:Cell Hypoxia / Q000502:physiology*; D002470:Cell Survival; D002478:Cells, Cultured; D002540:Cerebral Cortex / Q000503:physiopathology; D045304:Cytochromes c / Q000096:biosynthesis; D005947:Glucose / Q000172:deficiency; D006861:Hydrogen Peroxide / Q000494:pharmacology; D007770:L-Lactate Dehydrogenase / Q000378:metabolism; D053078:Membrane Potential, Mitochondrial / Q000235:genetics / Q000502:physiology; D018696:Neuroprotective Agents / Q000378:metabolism; D018384:Oxidative Stress; D050862:Oxidoreductases Acting on Sulfur Group Donors / Q000235:genetics*; D011065:Poly(ADP-ribose) Polymerases / Q000096:biosynthesis; D061251:Primary Cell Culture; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000096:biosynthesis; D034622:RNA Interference; D034741:RNA, Small Interfering; D051381:Rats; D017207:Rats, Sprague-Dawley; D051028:bcl-2-Associated X Protein / Q000096:biosynthesis
chemical_list: D051017:Apoptosis Regulatory Proteins; C494828:Bax protein, rat; D018696:Neuroprotective Agents; D019253:Proto-Oncogene Proteins c-bcl-2; D034741:RNA, Small Interfering; D051028:bcl-2-Associated X Protein; D045304:Cytochromes c; D006861:Hydrogen Peroxide; D007770:L-Lactate Dehydrogenase; D050862:Oxidoreductases Acting on Sulfur Group Donors; C542495:Srxn1 protein, rat; D011065:Poly(ADP-ribose) Polymerases; C506443:Casp12 protein, rat; D053454:Caspase 12; D053148:Caspase 3; D053453:Caspase 9; D005947:Glucose