Sulfiredoxin-1Ameliorates Oxidative Stress Injury Induced By Oxygen-glucose Deprivation And Hydrogen Peroxide In Rat Cortical Astrocytes Via Anti-apoptosis

Background:Astrocytes apoptosis plays a vital role in CNS injuries, such ascerebral ischemia, Alzheimer’s disease, and Parkinson’s disease.Sulfiredoxin-1(Srxn1), a central endogenous antioxidant protein, hasimportant neuroprotective functions in cerebral ischemia includingantioxidation and anti-apoptosis. However, the mechanisms of Srxn1during apoptosis in cerebral ischemia have not been well studied.Objective:To determine the role of Srxn1in protection from apoptosis inducedby OGD or H2O2and its possible mechanism.Methods:(1) We used lentiviral vector-encoding short hairpin RNAs (shRNAs)to transfect to astrocytes with interference Srxn1, and then exposed them toOGD for6h or100μM H2O2for6h to model oxidative stress injury.(2) We measured cell viability and cell damage as determined by MTSand LDH assays. (3) Using immunocytochemistry Hoechst33342and flow cytometryAV/PI double dye to detect cell apoptosis.(4) JC-1probe and Fluo-3,AM probe were used to detect the changeof mitochondrial membrane potential and intracellular free Ga2+usingLaser confocal.(5) Using WB to measure the protein of Srxn1, cyt.c, caspase-9,caspase-3, PARP, bax, bcl-2, and caspase-12；and QPCR to measure themRNA level of Srxn1.Results:(1) The results of MTS and LDH showed that interference Srxn1attenuated cell viability and increased cell damage(p<0.05， p<0.01).(2) Hoechst33342and FCM showed that interference Srxn1increased apoptosis(p<0.01).(3) JC-1staining showed that interference Srxn1induced dissipationof Δψm(p<0.01).(4) Interference Srxn1resulted in added the following apoptoticproteins: cyt.c, caspase-3, caspase-9, PARP, bax, and declined antiapoptoticbcl-2protein as determined by WB(p<0.05， p<0.01). But there was noobvious change in caspase-12protein after interference Srxn1(p>0.05).(5) Fluo-3,AM staining showed that after interference Srxn1the levelof intracellular Ca2+were not different from the control group(p>0.05). Conclusion:These results suggested that Srxn1can protect primary rat corticalastrocytes from OGD-or H2O2-induced cell apoptosis secondary toinvolvement of mitochondrial apoptotic pathways. Thus, the datademonstrated the potential of Srxn1as a target for neuroprotectiveintervention in apoptosis.