Figure 1. CypA improved cell viability in H₂O₂-stimulated A549 cells.

(A) Quantitative PCR analysis of PPIA mRNA levels in A549 cells treated with H₂O₂ (200 μM) for the indicated time periods. (B) Immunoblot analysis of CypA in A549 cells treated with H₂O₂ (200 μM) for the indicated time points. (C) LDH activity in culture medium of A549 cells treated with human recombinant CypA (hCypA) at different concentrations ranging from 100 to 1000 ng/ml for 24 h. (D) Cell viability of A549 cells pretreated with 500 ng/ml hCypA for he indicated time periods, and then stimulated with H₂O₂ (200 μM) for 24 h. (E) Cell viability of A549 cells pretreated with 100, 200, or 500 ng/ml hCypA for 2 h, and then treated with H₂O₂ (200 μM) for 24 h. Data information: The data are shown as the means ± SD (A, C–E: n=3). *P<0.05, **P<0.01, and ***P<0.001 (unpaired two-tailed Student’s t-test). The data are representative of at least three independent experiments.