Figure 3. Nrf2 knockout promotes PM2.5-induced oxidative stress in heart tissues. (A) SOD, GSH-Px, MDA and iNOS levels in serum of mice were measured. n = 8 in each group. (B) SOD, 3’-NT, 4-HNE and 8-OHdG levels in cardiac samples were determined. n = 8 in each group. (C, D) IHC staining of 8-OHdG and the quantification of its relative expression were exhibited. Scale bar was 100 μm. n = 6 in each group. (E) RT-qPCR analysis of SOD1, SOD2, NOX2 and NOX4 mRNA levels in heart samples. n = 6 in each group. (F, G) Western blot analysis of HO1, NQO1, GCLM and Keap1 protein expression in heart tissues. n = 6 in each group. Data were expressed as the mean ± SEM. *P < 0.05 and **P < 0.01.