FIGURE 1.

Identification of novel insulin mimetics. A, chemical structures of six compounds of 1,4-naphthoquinone derivatives. B, effects 1,4-naphthoquinone derivatives on IR phosphorylation in CHO-IR cells. CHO-IR cells were treated with different 1,4-naphthoquinone derivatives (5 μm) or insulin (100 nm) for 15 min. The amount of phosphorylated IR receptors was quantified by sandwich ELISA using immobilized anti-phosphotyrosine antibodies (pY20) anti-IR antibody. The activities of tested compounds were expressed as a percentage of the vehicle (DMSO) (n = 3).