Figure 2. Emodin inhibits the activity of the 26S proteasome in vitro and in vivo.
A. The chemical structure of emodin. B. HEK293A-luciferase-cODC cells were seeded in 96-well plates and treated in the presence of the indicated concentrations of emodin and 1 μM bortezomib for 3 h. C. The concentration-response curve of emodin. The calculated EC50 of emodin was 6.33 μM. D. HEK293A-luciferase-cODC cells were seeded in 96-well plates and treated with 10 μM emodin for the indicated period or treated with 10 μM MG132 for 2 h. The results are representative of 3 separate experiments. The error bars represent the standard deviation of the measurements. (*) p < 0.05, (**) p < 0.01, (***) p < 0.001 in comparison with the DMSO control.