Abstract: Objective To explore the possible mechanisms of Sulfiredoxin1 (Srxn1) for its antioxidant effects in astrocytes in response to oxidative stress induced by H2O2. Methods 1)Incubation and purification of astrocytes from the cerebral cortex of SD rats. 2)The lentiviral interference vector carrying Srxn1 or negative control(NC) shRNA were transduced into primary rat cortical astrocytes. And the knockdown efficiency of Srxn1 was measured by Real-time QPCR and Western blot assays. 3)H2O2 was treated after Srxn1 knockdown. Using LDH assays to measure cell damage. The intracellular oxidative stress state was estimated by superoxide dismutase(SOD) kit. The expression of Srxn1 and the activity of PrdxⅠ-Ⅳ and Prdx-SO2/3H were measured by WB. Results 1)WB revealed that the expression of Srxn1 was decreased to 40.8%（P<0.01）and Real-time QPCR showed that mRNA of Srxn1 was decreased to 36.4%（P<0.01）after knockdown of Srxn1. 2)Knockdown Srxn1 could increase the leakage rate of LDH to 23.4%（P<0.01）and decrease the level of SOD to 53.1%（P<0.01） after exposed to H2O2. 3)Exposed to H2O2 resulted in an increase in Srxn1 to 137.3%（P<0.01）. The expression of PrdxⅠ-Ⅳ can be increased by H2O2. However, it could be decreased after knockdown of Srxn1. Conclusion Srxn1 could alleviate oxidative stress injury for astrocytes and involved in Prdxs’ activity.

Key words: Sulfiredoxin1, interference, astrocytes, H2O2, Peroxiredoxin