Figure 3.

Purified Recombinant Adiponectin Activates AMPK in LβT2 Cells

A, Full-length adiponectin stimulates AMPK. LβT2 cells were serum starved overnight and then treated with 20 μg/ml recombinant mouse full-length adiponectin (fAd) for the times indicated. Phospho-AMPKα, phospho-ACC, and total AMPKα were detected by immunoblotting. B, Globular adiponectin stimulates ACC phosphorylation. LβT2 cells were serum starved overnight followed by treatments with 3 μg/ml of human globular adiponectin (gAd) for 5 min. Treatment with 1 mm AICAR for 1 h served as a positive control. For inhibition of AICAR-induced AMPK activation, compound C (20 μm) was added for 30 min before AICAR treatment. C, Dose-dependent phosphorylation of ACC by fAd (10 and 20 μg/ml) and gAd (3 and 10 μg/ml). Data shown are the fold induction of ACC phosphorylation (mean ± sd) from three experiments. Asterisk indicates statistical significance (P < 0.05). Cpd C, Compound C.