Figure 3. Knockdown of PIPOX abolishes pipecolate protection.
(A) Western blot analysis of PIPOX in HEK293 cells transfected with control siRNA (siCon, 100 nM) and PIPOX siRNA (siPIPOX, 100 nM) for 48 h. Actin was used as a control. (B) Percent cell survival of control siRNA (siCon) or PIPOX siRNA (siPIPOX) treated HEK293 cells with and without 0.5 mM H2O2 (3 h) in the absence (Con) and presence of 10 mM pipecolate (Pipe). (C) Percent cell survival of control siRNA or PIPOX siRNA treated HEK293 cells with and without 50 µM H2O2 (3 h) in the absence (Con) and presence of 1 mM or 5 mM pipecolate (Pipe). (D)Percent cell survival of control siRNA (siCon) or PIPOX siRNA (siPIPOX) treated HEK293 cells with and without 500 µM H2O2 (3 h) in the absence (Con) and presence of 5 mM proline. Percent cell survival in all experiments was estimated using the MTS cell viability assay. Each value represents mean ± SD of separate experiments (n = 5) (*P < 0.05).