Effects of black cohosh on estrogen biosynthesis in normal breast tissue in vitro.
OBJECTIVE
To investigate the effect of black cohosh on the estrogen biosynthesis in the breast in vitro.


METHODS
Steroid sulfatase (STS) activity was studied in normal breast tissue obtained from pre- and postmenopausal women undergoing reduction mammoplasty. STS protein expression was studied by immunohistochemistry and western blotting. Breast tissue was incubated in vitro without or with black cohosh (iCR) at concentrations ranging from 0.1mg/ml to 1 ng/ml. STS activity was evaluated by incubating homogenized breast tissue with [3H]-estrone sulfate, separating the formed products, estrone (E1) and estradiol (E2), by thin layer chromatography and measuring the amounts of E1 and E2 by scintillation counting.


RESULTS
STS protein expression and enzymatic activity were detected in all specimens investigated. In all groups, significantly more E1 than E2 was produced. Local estrogen formation was decreased in premenopausal breast tissue by treatment with iCR at 0.1mg/ml (p<or=0.05).


CONCLUSIONS
iCR decreases local estrogen formation in normal human breast tissue in vitro. This may contribute to the lack of hormonal effects of black cohosh in breast tissue observed in previous studies.
Stute
Petra
P
Department of Obstetrics and Gynecology, University Clinic of Muenster, 48149 Muenster, Germany. stutepe@mednet.uni-muenster.de
Nisslein
Thomas
T
Götte
Martin
M
Kamischke
Axel
A
Kiesel
Ludwig
L
Klockenbusch
Walter
W
D000328:Adult; D000368:Aged; D001940:Breast / Q000166:cytology / Q000187:drug effects / Q000378:metabolism*; D031885:Cimicifuga; D004305:Dose-Response Relationship, Drug; D004967:Estrogens / Q000378:metabolism*; D005260:Female; D006801:Humans; D008875:Middle Aged; D010936:Plant Extracts / Q000494:pharmacology*; D043266:Steryl-Sulfatase / Q000378:metabolism
D004967:Estrogens; D010936:Plant Extracts; D043266:Steryl-Sulfatase