Effects of TrxR1 knockdown by siRNA in SH-SY5Y cells.

<p><i>A,</i> Successful transfection of SH-SY5Y cells with a fluorescein-labeled scrambled-control siRNA. Photomicrographs were captured under a fluorescence microscope at a 400× original magnification at the end of the transfection period. BF, bright field; FAM, fluorescence from fluorescein-labeled scramble-siRNA. B, C, Relative protein expression and mRNA levels of TrxR1 are decreased in the siRNA-1 and siRNA-4 groups at 24 hours post-transfection as compared with the non-transfected control group. The results are the means±S.D. of three separate experiments; ^a<i>P</i><0.05 versus the control group. D, The effects of an siRNA mixture (siRNA-1 and siRNA-4) on the S-nitrosylation and phosphorylation of nNOS in SH-SY5Y cells induced by OGD for 5 hours followed by 6 hours of reoxygenation. The bands shown are representative of three independent experiments; ^a<i>P</i><0.05 versus the control group; ^b<i>P</i><0.05 versus the negative control (NC) group. <i>E,</i> DAPI staining of SH-SY5Y cells induced by OGD for 5 h followed by 24 h of reoxygenation. Typical apoptotic cells with a condensed nucleus are indicated by arrowheads. Quantitative representations are expressed as a percentage of the total cells in 10 microscopic fields (×400) for DAPI staining. ^a<i>P</i><0.05 versus the control group; ^b<i>P</i><0.05 versus the NC group.