Inhibitory effects of apigenin and kaempferol on the essential solute carrier transporters

Figure 3 Inhibitory potency of apigenin and kaempferol on the uptake of estrone-3-sulfate mediated by organic anion transporter 3. A: IC₅₀ of apigenin inhibition on OAT3; B: IC₅₀ of kaemperol inhibition on OAT3. The OAT3 mediated uptake of [³H]-estrone-3-sulfate with the presence of a range of varying concentrations of apigenin or kaempferol (0.0001 to 50 µmol/L) were measured. The transporter-mediated uptake was calculated by subtracting the uptake of vector control and expressed as a percentage of the uptake for the control (without presence of apigenin or kaemperol). Values were mean ± SE (n = 3) of triplicate repeats in three independent experiments. The IC₅₀ value of each compound was then calculated by nonlinear regression models in GraphPad Prism 6.0. OAT3: Organic anion transporter 3.