ABSTRACT
OBJECTIVE: To screen the estrogenic effects of fresh Radix Rehmanniae, dried Radix Rehmanniae, Radix Rehmanniae Praeparata and the leaves of Rehmannia glutinosa Libosch. METHODS: Mouse uterine weight test and MCF-7 cell proliferation assay were used to evaluate the estrogenic effects of the four kinds of Chinese traditional herbs. ICI182, 780 antagonnist assay and reporter gene assay were adopted to explore the mechanism of action of fresh and dried Radix Rehmanniae. In reporter gene assay, HEK293 cells were cotranfected with pERE-TAL-luc, pβgal-Control, pCXN2-hERα or pCXN2-hERβ, and the expression of reportr gene luc was controlled by ERE. RESULTS: Mouse uterine weight test showed that compared with the control group, fresh and dried Radix Rehmanniae could increase the uterus index of premature female mice, and both of them could promote the proliferation of MCF-7 cells. Co-incubation of MCF-7 cells with estrogen receptor blocker ICI182, 780 abolished the inductive effect of the proliferation. The reporter gene controlled by ERE technology showed that when mediated by ERβ, the normalized luciferase activity of the two groups were significantly higher than the activity of the control group. CONCLUSION: Fresh and dried Radix Rehmanniae have estrogenic activities which are mainly mediated by ERβ. Fresh Radix Rehmanniae has higher estrogenic activity than dried Radix Rehmanniae. Radix Rehmanniae Praeparata does not have estrogenic activity. The estrogenic activity may change during the processing process of Rehmannia glutinosa Libosch.