Fig. 4

AMPK activation increases the engulfment of HMGB1 in an SR-A1-dependent manner in mouse BMDMs. A rHMGB1 (his tag) contents in BMDMs treated with AICAR (300 μM) in the presence of receptor-dependent endocytic pathway inhibitors (TLR4 inhibitor: CLI095, 10 μM; RAGE inhibitor: FPS-ZM1, 100 nM). rHMGB1 (his tag) contents in BMDMs treated with AICAR (300 μM) (B, C and D) or metformin (2.5 mM) (E and F) in the presence of anti-SR-A1 antibody (2 μg/ml), SR-A1 inhibitor dextran sulfate sodium salt (100 μg/ml) or SR-A1 KO (n = 3). G Phosphorylation of AMPK in the DRG of mice. DRG samples were collected on the 14th day after the first administration of L-OHP (3 mg/kg, i.p.) or vehicle (n = 3). BMDMs^{SR−A1−/−} (D) (F) were isolated from the bone marrow of SR-A1 KO mice. BMDMs were administered with/without CQ (20 μM) for 15 min, administered with inhibitors or anti-SR-A1 Ab for 15 min, then treated with AMPK agonist (AICAR or metformin) for 15 min, followed by co-culturing with rHMGB1 (his tag) (10 nM) for 1 h, and subsequently collected for western blotting. Representative bands and a data summary (n = 3 for each group) are shown. A significant difference was revealed following one-way ANOVA (*p < 0.05, **p < 0.01 and ***p < 0.001 vs. Control; ^#p < 0.05, ^##p < 0.01 and ^###p < 0.001 vs. AICAR group or metformin group; Bonferroni post hoc tests)