Fig. 3.

GEVs regulated proinflammatory cytokine transcription and secretion through the p38 MAPK and ERK signaling pathways in a positive feedback manner and the Akt signaling pathway in a negative feedback manner. Mouse macrophages were pretreated with the p38 MAPK inhibitor SB203580 (30 μM), ERK inhibitor SCH772984 (300 nM) or AKT inhibitor MK-2206 2HCl (5 μM) for 2 h. Unpretreated groups were used as controls. The inhibited cell groups were inoculated with GEVs for 2, 4 and 4 h. a–c The phosphorylated protein expression levels of p38, ERK and AKT were measured using western blotting, and the gray values of phosphorylated protein/β-actin were calculated using ImageJ software. d–f Levels of proinflammatory cytokine transcription levels in cells collected 6 h after inoculation were detected using real-time quantitative PCR assays (qPCR). g–i Levels of proinflammatory cytokine transcription levels in cells collected 12 h after inoculation were detected using qPCR assays. j–l Levels of proinflammatory cytokine protein secretion levels were detected in supernatants collected 18 h after inoculation using ELISAs. The results show the mean ± SEM of triplicate experiments. Signficant differences vs noninhibitor treatment control: *p < 0.05, **p < 0.01, ***p < 0.001