Figure 3.

Effect of the AuNPs on Nrf2 expression and translocation and Bach1 export.

Notes: (A) The cells were treated with (a) the indicated concentrations of the AuNPs for 4 hours or (b) 2 ppm of the AuNPs for the indicated time intervals, and Nrf2 expression was analyzed by Western blotting and RT-PCR (n=3). (B) The cells were treated with the AuNPs (2 ppm) for the indicated time intervals. The subcellular distribution (translocation/export) of Nrf2 and Bach1 was analyzed by Western blotting (n=3–4). (C) Immunofluorescence microscopy of subcellular distribution of (a) Nrf2 and (b) Bach1. The cells were treated with the AuNPs (5 ppm) for 3 hours. After fixation and permeabilization, the cells were stained with anti-Nrf2 and anti-Bach1 Abs, followed by staining with DAPI. The cells were photographed under the microscope. The nuclear-positive stained cells (green and indigo colors, arrows) and the total cells in the “Merge” panels were counted (n=4). The number of cells with Nrf2 translocation and Bach1 export was expressed as the nuclear-positive stained cells/total cells. ***P<0.001 versus the control.

Abbreviations: AuNPs, gold nanoparticles; Bach1, BTB and CNC homolog 1; DAPI, 4′,6-diamidino-2-phenylindole; HPF, high-power field; Nrf2, nuclear factor erythroid 2-related factor 2; RT-PCR, reverse transcription polymerase chain reaction.