Fig. 3.

Effects of diprotin A and berberine on mDPP4 enzymatic activity, cell profiles, and T helper-specific cytokine expression in H9 Th1 cells. (A) The chemical structures of diprotin A and berberine, representative DPP4 inhibitors, but not antidiabetic drugs, are shown. (B-D) Cell pellets and culture supernatants were harvested 12 h after treatment of H9 Th1 cells with diprotin A and berberine (dose range, 0-20 µg/mL) in the presence of 10 µg/mL PWM. The mDPP4 enzymatic activity of the cell pellets was determined (B). The cell profiles, including cell counts and viability, of the PWM-treated cells with or without DPP4 inhibitors were determined (C). The values of Th1-specific cytokines, including IL-2, IL-10, IL-13, GM-CSF, IFN-γ, and TNF-α, and VEGF in the culture supernatants were measured simultaneously (D). All analyses were the same as those described in Fig. 2.