Figure 2

Effects of AMPK activation or inhibition on neutrophil chemotaxis. Neutrophils were pretreated with compound C (0), 1,2,3 or 10 µmol/L) for 60 min, metformin (500 µmol/L) or berberine (10 µmol/L) for 2.5 h and then chemotaxis was measured after inclusion of cells in transmigration chambers and exposure to W-peptide for 60 min. (A) Representative images show amount of control (untreated) or compound C-treated (30 µmol/L) neutrophils that migrated into the lower reservoir. Panel (B) shows dose-dependent inhibition by compound C, whereas (C) metformin exposure or berberine exposure enhanced neutrophil chemotaxis. Means ± SD (n = 3), *P < 0.05, compared with control. Lower panels B or C show Western blots of phospho AMPK, total AMPK and actin obtained from neutrophils treated with compound C (10 µmol/L) for 60 min, metformin (500 µmol/L) for 2.5 h, or berberine (10 µmol/L) for 2.5 h. (D) Chemotaxis assays were performed in control (untreated) cells and cells treated with control (scrambled siRNA) or specific siRNA to AMPKα1 subunit. (E) Representative Western blots show amounts of AMPKα1 and actin before and after treatment with scrambled or siRNA to AMPKα1. ctr, Control; met, metformin; ber, berberine; scr., scrambled.