Figure 3.

Effects of the isolated compounds on estrogen biosynthesis. (A) KGN cells seeded in 96-well plates were pretreated with the test compounds at 10 μg/mL for 24 h. Alamar Blue reagent was added and the plates were incubated for a further 4 h, after which the fluorescence intensities were measured. (B) KGN cells seeded in 24-well plates overnight were pretreated with the test compounds for 24 h. Subsequently, the cells were supplemented with 10 nM testosterone for a further 24 h. The concentration of 17β-estradiol in the culture medium was quantified using a 17β-estradiol magnetic particle-based ELISA. (C) The concentration-response curve of compounds 1–4 for promotion of estrogen biosynthesis in KGN cells. FSK, 10 μM forskolin; Let, 1 μM letrozol. *p < 0.05, **p < 0.01, ***p < 0.001 compared with the control (n = 3).