Figure 2.

Effects of melatonin on nickel-induced aerobic glycolysis. Cells were exposed to NiCl₂ (50, 100, 200, and 400 μM) for 24 h. The effects of 1 mM melatonin on aerobic glycolysis in nickel-treated cells were evaluated. The glycolysis levels of cells, indicated by the extracellular acidification rate, were evaluated by a Seahorse® extracellular flux analyzer (a). The activities of phosphofructokinase (PFK), a key enzyme for glycolysis, were measured with a colorimetric based kit (b). Cellular energy metabolite levels, including the concentrations of ATP (c) and lactic acid (d), were measured in treated cells. The error bar reflects the S.E.M. of at least three independent experiments. ^∗P < 0.05 compared with nickel-free control group, and ^#P < 0.05 compared with the same nickel concentration but with the melatonin-free group.