Effects of a breast-health herbal formula supplement on estrogen metabolism in pre- and post-menopausal women not taking hormonal contraceptives or supplements: a randomized controlled trial.

INTRODUCTION: Both indole-3-carbinol and dietary lignans have beneficial effects on estrogen metabolism and breast cancer risk. There is no published literature on the effects of a combination product. This study was designed to investigate the impact of a combination product on estrogen metabolism. The major trial objective was to determine whether a breast health supplement containing indole-3-carbinol and hydroxymatairesinol lignan would alter estrogen metabolism to favour C-2 hydroxylation and reduce C-16 hydroxylation. Higher concentrations of C-2 metabolites and lower concentrations of C-16 metabolites may reduce breast cancer risk and risk for other hormonally-related cancers. METHODS: Forty-seven pre-menopausal and forty-nine post-menopausal women were recruited for this study, and were divided by random allocation into treatment and placebo group. The treatment supplement contained HMR lignan, indole-3-carbinol, calcium glucarate, milk thistle, Schisandra chinesis and stinging nettle, and each woman consumed either treatment or placebo for 28 days. At day 0 and day 28, blood samples were analysed for serum enterolactone concentrations, and first morning random urine samples were assessed for estrogen metabolites. Repeated measures ANOVA statistical testing was performed. RESULTS: In pre-menopausal women, treatment supplementation resulted in a significant increase (P < 0.05) in urinary 2-OHE concentrations and in the 2:16α-OHE ratio. In post-menopausal women, treatment supplementation resulted in a significant increase in urinary 2-OHE concentrations. In pre- and post-menopausal women combined, treatment supplementation produced a significant increase in urinary 2-OHE concentration and a trend (P = 0.074) toward an increased 2:16α-OHE ratio. There were no significant increases in serum enterolactone concentrations in the treatment or placebo groups. CONCLUSIONS: Supplementation with a mixture of indole-3-carbinol and HMR lignan in women significantly increased estrogen C-2 hydroxylation. This may constitute a mechanism for the reduction of breast cancer risk as well as risk for other estrogen-related cancers. Further studies with higher numbers of subjects are indicated.

Lycium barbarum inhibits growth of estrogen receptor positive human breast cancer cells by favorably altering estradiol metabolism.

Selective estrogen receptor modulators represent accepted therapy for estrogen receptor positive (ER+) breast cancer, exhibit adverse side effects, and reduce patient compliance. The use of phytoestrogen containing herbal medicines is limited because of efficacy and safety concerns. The ER+ MCF-7 model examined growth inhibitory effects of the medicinal herb Lycium barbarum (LB) and identified mechanistic leads for its efficacy. The MCF-7 cells maintained in 0.7% serum (17beta-estradiol, E2 < 1 nM) exhibited 11%-87% increased growth after treatment with 1nM to 20 nM E2. Growth promotion with 20 nM E2 exhibited 5.2-fold increased estrone (E1), 35.7% increased 2-hydroxyestrone (2-OHE1), 15.4% increased 16alpha-hydroxyestrone (16alpha-OHE1), and eightfold increased estriol (E3) formation. Treatment of E2 stimulated cells with LB exhibited a dose-dependent growth inhibition of 9.5%-42.8% at Day 3 and 33.9%-83.9% at Day 7. The 3-day inhibitory response to 1% LB (maximum cytostatic concentration) exhibited 84.8% increased E1, 3.6-fold increased 2-OHE1, 33.3% decreased 16alpha-OHE1, and 9.2-fold increased E3 formation. Thus, MCF-7 cells retain their mitogenic and metabolic response to E2 and LB downregulates E2-stimulated growth via the formation of antiproliferative 2-OHE1 and accelerated conversion of mitogenic 16alpha-OHE1 to antimitogenic E3.

Dietary seaweed modifies estrogen and phytoestrogen metabolism in healthy postmenopausal women.

Seaweed and soy foods are consumed daily in Japan, where breast cancer rates for postmenopausal women are significantly lower than in the West. Likely mechanisms include differences in diet, especially soy consumption, and estrogen metabolism. Fifteen healthy postmenopausal women participated in this double-blind trial of seaweed supplementation with soy challenge. Participants were randomized to 7 wk of either 5 g/d seaweed (Alaria) or placebo (maltodextrin). During wk 7, participants also consumed a daily soy protein isolate (2 mg isoflavones/kg body weight). After a 3-wk washout period, participants were crossed over to the alternate supplement schedule. There was an inverse correlation between seaweed dose (mg/kg body weight) and serum estradiol (E2) (seaweed-placebo = y = -2.29 x dose + 172.3; r = -0.70; P = 0.003), [corrected] which was linear across the range of weights. Soy supplementation increased urinary daidzein, glycitein, genistein, and O-desmethylangolensin (P = 0.0001) and decreased matairesinol and enterolactone (P < 0.05). Soy and seaweed plus soy (SeaSoy) increased urinary excretion of 2-hydroxyestrogen (2-OHE) (P = 0.0001) and the ratio of 2-OHE:16alpha-hydroxyestrone (16alphaOHE(1)) (P = 0.01). For the 5 equol excretors, soy increased urinary equol excretion (P = 0.0001); the combination of SeaSoy further increased equol excretion by 58% (P = 0.0001). Equol producers also had a 315% increase in 2:16 ratio (P = 0.001) with SeaSoy. Seaweed favorably alters estrogen and phytoestrogen metabolism and these changes likely include modulation of colonic bacteria.

Comparison of plasma and urinary levels of 2-hydroxyestrogen and 16 alpha-hydroxyestrogen metabolites.

A modified ELISA assay for measurement of the two estrogen metabolites 2-hydroxyestrone (2OHE1) and 16alpha-hydroxyestrone (16alphaOHE1) in plasma and serum has been developed. Previously, these have only been measured in urine. It is not known how well the measurements of these metabolites in urine and plasma are correlated. The goal of this study was to compare urinary and plasma levels of 2OHE1 and 16alphaOHE1 and their ratios and to explore how they were affected by ethnicity, dietary and genetic factors, and medication use. Blood and urine samples were obtained from 511 nulliparous women, aged 17-35, from four ethnic groups during the same visit at the study center, on a random day of the menstrual cycle. The overall correlation between the 2OHE1/16alphaOHE1 ratio in plasma and urine was fair (rs = 0.52; p < 0.0001). In general, the correlation between the 2OHE1/16alphaOHE1 ratio in urine and plasma was higher among women not using oral contraceptives (OCs) (rs = 0.58; p < 0.0001) than among women currently using OCs (rs = 0.34; p < 0.0001). The correlation was highest for samples obtained during the mid-cycle in among non-OC users (rs = 0.83; p < 0.0001). Among non-OC users, the urinary 2OHE1/16alphaOHE1 ratio was stable over the menstrual cycle while there was an increase in the plasma 2OHE1/16alphaOHE1 ratio. The strongest factors predicting discordance between the urinary and plasma 2OHE1/16alphaOHE1 ratios among non-OC users were a baseline urinary 2OHE1/16alphaOHE1 ratio in the three upper quartiles (p < 0.001), the menstrual cycle phase (p = 0.001), and the number of cups of coffee consumed per day (p = 0.006). Among current OC users, the strongest predictors of discordance between the urinary and plasma 2OHE1/16alphaOHE1 ratios were a baseline urinary 2OHE1/16alphaOHE1 ratio in the three lower quartiles (p < 0.001), being black (p = 0.001), and being Asian (p = 0.014). In conclusion, we found that the correlation between the two methods was fair and varied according to the baseline urinary 2OHE1/16alphaOHE1 ratio, ethnic group, OC status, coffee consumption, and time of menstrual cycle when the samples were obtained.