Estrogenic activity of triterpene glycosides in yeast two-hybrid assay.
Estrogenic potency of six triterpene glycosides, Holothurin A, Holotoxin A1, Frondoside A, Cucumarioside A2-2 and Cauloside C, that are natural products and semi-synthesized Ginsenoside-Rh2, were examined with yeast two-hybrid system, including expressed genes of human estrogen receptor, hERalpha, the co-activator TIF2 and lacZ as a reporter gene. Only Ginsenoside-Rh2 exhibited significant moderate estrogenic activity in the concentration range of 10(-7) to 10(-6)M. Its effect was approximately 30% of the activity of 17beta-estradiol applied at half-effective concentration. This indicates Ginsenosides-Rh2 is a weak phytoestrogen. The sea cucumber triterpene glycosides, Holothurin A, Holotoxin A1, Cucumarioside A2-2 and Frondoside A, and plant glycoside Cauloside C had no appreciable estrogenic activity. Data obtained by yeast two-hybrid assay reflect structure-activity relationship between tested compounds and 17beta-estradiol. Only Ginsenoside-Rh2 has some similarity in chemical structure with 17beta-estradiol that might explain affinity of this glycoside to the hERalpha receptor.
Kovalchuk
S N
SN
Pacific Institute of Bioorganic Chemistry, Far Eastern Branch of RAS, Vladivostok 690022, Russia.
Kozhemyako
V B
VB
Atopkina
L N
LN
Silchenko
A S
AS
Avilov
S A
SA
Kalinin
V I
VI
Rasskazov
V A
VA
Aminin
D L
DL
D000818:Animals; D004305:Dose-Response Relationship, Drug; D006027:Glycosides / Q000737:chemistry*; D006801:Humans; D015394:Molecular Structure; D011960:Receptors, Estrogen / Q000737:chemistry*; D014315:Triterpenes / Q000737:chemistry*; D020798:Two-Hybrid System Techniques
D006027:Glycosides; D011960:Receptors, Estrogen; D014315:Triterpenes