Fig. 4

The roles of KEAP1 in CuONPs-induced NRF2 activation. A, B Immunoblotting analysis and quantification of KEAP1 protein levels in HUVECs cells treated with 0, 5, 10, 15, 20 μg/mL CuONPs for 12 h, respectively. L.E, longer exposure time. GAPDH served as an internal control. C, D Immunoblotting analysis and quantification of KEAP1 protein levels in HUVECs cells treated with 20 μg/mL CuONPs for 0, 3, 6, 9 and 12 h, respectively. E, F Immunoblotting analysis and quantification protein levels of KEAP1, NRF2, HMOX1 and β-Actin (loading control) in WT and KEAP1 knockdown (KEAP1-KD) cells treated with 20 μg/mL CuONPs for 0, 6 and 9 h, respectively. ns, not significance. G Representative images of cell morphology of WT and KEAP1-KD cells treated with 20 μg/ml CuONPs for 12 h. Scale bar, 100 μm. In B and D, Student’s t-test was used for statistical significance. In F, statistical significance was evaluated using one-way ANOVA followed by a Tukey multiple comparison test. All data are representative of three independent experiments. The values are expressed in mean ± S.D. ns not significance; “*”, P ≤ 0.05; **”, P ≤ 0.01; “***”, “P ≤ 0.001”