(R) -Equol

(R) -Equol is an ERα and ERβ agonist with Kis of 27.4 and 15.4 nM, respectively. (In Vitro) : (R) -Equol produced a dose-dependent inhibitory effect on the invasive ability of MDA-MB-231 cells, and this inhibitory effect was obvious at the highest test concentration (50 μM) .Following 48-h exposure to (R) -Equol, invasion is reduced by 62% (p=0.009, versus untreated cells) with 50 μM (R) -Equol. Matrix metalloproteinase-2 (MMP-2) expression is significantly down-regulated following treatment with 50 μM (R) -Equol (p=0.035) . (In Vivo) :In Animals, (R) -Equol has a significantly reduced number of palpable tumors over time when compared with Controls (P=0.002) .In addition, the number of palpable tumors formed by each rat in the (R) -Equol fed group was significantly lower than that of rats treated with S- (-) equol (P = 0.008) . (R) -Equol-fed animals have 43% fewer tumors than the control group and this difference is highly statistically significant (P=0.004) . The number of tumors/tumor-bearing animals is significantly lower in the animals fed (R) -Equol compare with Controls (3.3±0.4 versus 5.5±0.5, P=0.004) . At necropsy, the mean (±SEM) tumor weight per animal for (R) -Equol fed rats (5.3±1.1 mg) is significantly reduced (P=0.04) when compared with Controls (9.9±1.4 mg) . Feeding the (R) -Equol diet results in significantly increased tumor latency (P=0.003) .