Fig. 5
SiO2-Exo promotes the inflammatory response by regulating the activation of the STAT3/MAPK (ERK1/2 and p38)/NF-κB signalling pathways. (A) Western blot analysis of the expression of pro-IL-1β and the phosphorylation of p65 (NF-κB), STAT1/3, AKT, ERK1/2 and p38 in RAW264.7 macrophages treated with PBS, NC-Exo or SiO2-Exo. # indicates that the data were compared between the NC-Exo group and the SiO2-Exo group. (B) Western blot analysis of the expression of pro-IL-1β and the phosphorylation levels of p65 (NF-κB), STAT1/3, AKT, ERK1/2 and p38 in RAW264.7 macrophages treated with SiO2-Exo or SiO2 + GW4869-Exo. (C) Western blot analysis of the expression of pro-IL-1β and the phosphorylation of STAT3 and AKT in SiO2-Exo-induced RAW264.7 macrophages treated with Stattic (5 µM) or MK2206 (10 nM). (D) ELISA analysis of the release of IL-1β, IL-6 and TNF-α in the SN of SiO2-Exo-induced RAW264.7 macrophages treated with Stattic (5 µM) or MK2206 (10 nM). n = 3 each group. The data are representative of three individual experiments and expressed as the mean ± SEM. The data were analysed by Student’s t test or two-way ANOVA. *P < 0.05, **P < 0.01, ***P < 0.001, ****P < 0.0001, ns = not significant. Abbreviations SiO2 = silica dust; SN = cell culture supernatant; NC-Exo = exosomes derived from cells without SiO2 exposure; SiO2-Exo = exosomes derived from SiO2-exposed macrophages; SiO2 + GW4869-Exo = exosomes derived from SiO2-exposed macrophages treated with GW4869 (10 µM)