Both wortmannin and simvastatin inhibit the adipogenesis in 3T3-L1 cells during the late phase of differentiation.

As we reported previously, both wortmannin and lovastatin inhibit the differentiation in 3T3-L1 cells when these drugs were applied during the insulin-induced cell differentiation. In the present study, 3T3-L1 cells were treated with wortmannin and simvastatin after the completion of the insulin-stimulation, and differentiation was found to be significantly decreased by these drugs. This suggests intracellular signaling pathways play roles in the differentiation of 3T3-L1 cells even after the completion of the insulin-stimulation and also suggests that not only the early phase (day 0 to day 2) but also the late phase (day 2 to day 4) of differentiation is important for the differentiation of the cells.