Metformin revisited: Does this regulator of AMP-activated protein kinase secondarily affect bone metabolism and prevent diabetic osteopathy

Figure 2 Metformin induces an increase and redistribution of activated AMP-activated protein kinase in multinucleated osteoclasts. UMR106 osteoblasts and Raw 264.7 macrophages were co-cultured for 7 d, in the absence (A) or presence (B) of 500 mol/L metformin. Cells were fixed, permeabilized and incubated with an anti-phosphorylated AMPK antibody, followed by a FITC-conjugated secondary antibody (green). Nuclei were counterstained with propidium iodide (red). Cells were visualized with a Leica TSC SP5 AOBS confocal microscope. Metformin induced an increase in activated AMPK with a punctillate and predominantly cytoplasmic distribution. AMPK: AMP-activated protein kinase.