PDZ peptide dramatically increases M2 marker proteins to regulate M1/M2 polarization via NF-κB signaling and ROS production.
(a, c, e, g) The cells were treated with LPS in a time-dependent manner. After treatment with WT PDZ and mutant PDZ, the cells were treated with LPS for 4 hrs (b, d, f) or 1 hr (h). The mitochondria morphology was stained using MitoTracker® Green FM and visualized (a, b). The mitochondria fission was stained using phospho-Drp1 antibody and visualized (c, d). The phospho-specific and total antibodies were assessed by Western blot analysis. β-actin was used as a loading control (e, f). The lysates were prepared for qPCR for the expression of M1 and M2 marker proteins (g, h). *p < 0.05 compared with control; **p < 0.05 compared with LPS treatment; ***p < 0.05 compared with WT PDZ-treated transfectants. All of the data shown are representative of three independent experiments. (i) A graphic abstract illustrating that PDZ peptide of ZO-1 protein inhibits LPS-induced systemic inflammation by regulating the activation of NF-κB signaling pathways, ROS production, and M1/M2 polarization.