Effects of soybean glyceollins and estradiol in postmenopausal female monkeys.
Glyceollins are a novel class of soybean phytoalexins with potential cancer-protective antiestrogenic effects. The purpose of this study was to evaluate the estrogen-antagonist effects of glyceollin-enriched soy protein on biomarkers for breast cancer risk. Thirty female postmenopausal cynomolgus macaques were randomized to one of three dietary treatments for 3 wk: 1) estradiol (E2, 1 mg/day) + casein/lactalbumin (control); 2) E2 + soy protein isolate (SPI) containing 194 mg/day isoflavonoids; and 3) E2 + glyceollin-enriched soy protein (GLY) containing 189 mg/day isoflavonoids + 134 mg/day glyceollins. Doses are expressed in calorically scaled human equivalents. Mean serum glyceollin concentrations at 4 h postfeeding were 134.2 +/- 34.6 nmol/L in the GLY group and negligible in the SPI group (P = 0.0007). Breast proliferation was significantly increased in the control group (+237%, P = 0.01) but not in the SPI group (+198%, P = 0.08) or GLY group (+36%, P = 0.18). Gene expression of trefoil factor 1 and progesterone receptor, two markers of estrogen receptor activity in breast epithelium, were also significantly higher in the control (P < 0.05 for both) but not in the GLY group. These preliminary findings suggest that soybean glyceollins are natural compounds with potential estrogen-modulating properties in the breast.
Wood
Charles E
CE
Department of Pathology/Section on Comparative Medicine, Wake Forest University School of Medicine, Winston-Salem, NC 27157, USA. chwood@wfubmc.edu
Clarkson
Thomas B
TB
Appt
Susan E
SE
Franke
Adrian A
AA
Boue
Stephen M
SM
Burow
Matthew E
ME
McCoy
Thomas
T
Cline
J Mark
JM
D000818:Animals; D016588:Anticarcinogenic Agents / Q000494:pharmacology*; D001578:Benzopyrans / Q000097:blood / Q000494:pharmacology*; D015415:Biomarkers; D014408:Biomarkers, Tumor; D001943:Breast Neoplasms / Q000097:blood / Q000473:pathology / Q000517:prevention & control; D004958:Estradiol / Q000097:blood / Q000494:pharmacology*; D005260:Female; D015870:Gene Expression; D007150:Immunohistochemistry; D007529:Isoflavones / Q000097:blood / Q000494:pharmacology; D008252:Macaca fascicularis / Q000097:blood*; D008321:Mammary Glands, Animal / Q000187:drug effects* / Q000378:metabolism / Q000473:pathology; D010052:Ovariectomy; D010455:Peptides / Q000378:metabolism; D017698:Postmenopause / Q000097:blood; D036343:Pterocarpans; D011980:Receptors, Progesterone / Q000378:metabolism; D030262:Soybean Proteins / Q000494:pharmacology; D013025:Glycine max / Q000737:chemistry*; D000071164:Trefoil Factor-2
D016588:Anticarcinogenic Agents; D001578:Benzopyrans; D015415:Biomarkers; D014408:Biomarkers, Tumor; D007529:Isoflavones; D010455:Peptides; D036343:Pterocarpans; D011980:Receptors, Progesterone; D030262:Soybean Proteins; D000071164:Trefoil Factor-2; D004958:Estradiol; C017343:glyceollin