ABSTRACT
This study offers preliminary insight into the phytoestrogen activity and mechanism of rehmapicrogenin. In this study, we characterized the estrogenic activity of rehmapicrogenin using immature female mice in vivo and MCF-7 cell proliferation assay in vitro. All the procedures for the care of the mice were conducted in accordance with the Regulations of Experimental Animal Administration issued by the State Committee of Science and Technology of the People’s Republic of China. Uterine wet weight/body mass ratios, Western blot assay for estrogen receptor, and serum estrogen levels of estradiol (E2), luteinizing hormone (LH) and follicle stimulating hormone (FSH) were investigated. The effects of rehmapicrogenin, and the estrogen receptor antagonist ICI182,780, the estrogen receptor alpha antagonist MPP, the estrogen receptor beta antagonist THC, the G-protein coupled receptor 30 antagonist G15 combined with rehmapicrogenin on cell proliferation were examined in MCF-7 cells. Rehmapicrogenin (50 mg·kg-1) treatments demonstrated significant estrogenic activity by promoting the development of uterus in immature female mice, as well as increasing the expression of estrogen receptor alpha (ERα) and G-protein coupled receptor 30 (GPR30) at the protein level in uterus, and decreasing FSH and LH compared with the control group. Meanwhile, rehmapicrogenin (6 and 8 μmol·L-1) promoted the proliferation of MCF-7 cells, which were significantly antagonized by ICI182,780, MPP and G15. This study demonstrates rehmapicrogenin exerts estrogenic effects through ERα and GPR30.