Fig. 1

ROS has a concentration-dependent effect on macrophages M1 polarization, and LPS can promote macrophages M1 polarization by inducing ROS production. A and B Raw264.7 cells cultured with different concentration of H₂O₂ (ranging from 50 μmol/L to 500 μmol/L) for 24 h. M1 polarization rate was increased with an increased H₂O₂ concentration in the culture medium. C and D Raw264.7 cells cultured with LPS for 2, 4, 6 and 24 h. ROS level was detected by using FACS with a flow cytometry. E and F Raw264.7 cells cultured with LPS or H₂O₂ for 2, 4 and 6 h.The mRNA (iNOS) relative expression level of M1 phase is detected. Both LPS and H₂O₂ markedly upregulated the expression of iNOS at 6 h after LPS and H₂O₂ treatment. *p < 0.05, ***p < 0.01