Resveratrol goede vervanger voor hormoontherapie*
Door de risico’s verbonden aan hormoontherapieën die de laatste jaren bekend geworden zijn gingen steeds meer vrouwen over op natuurlijke middelen zoals
soja en rode klaver om de
menopauzale problemen als gevolg van een dalend oestrogeenniveau aan te pakken. Uit deze laboratoriumstudie nu blijkt dat er waarschijnlijk een nog beter alternatief is en wel
resveratrol. De onderzoekers vergeleken de effecten van nutriënten als
resveratrol en genisteïne, glysteïne en daidzeïne allemaal van soja. Resveratrol bleek de beste te zijn in het nabootsen van de effecten van oestrogeen.
Effects of diverse dietary phytoestrogens on cell growth, cell cycle and apoptosis in estrogen-receptor-positive breast cancer cells
Takako Sakamoto , Hyogo Horiguchi, Etsuko Oguma, Fujio Kayama
Abstract
Phytoestrogens have attracted attention as being safer alternatives to hormone replacement therapy (HRT) and as chemopreventive reagents for breast cancer because dietary soy isoflavone intake has been correlated with reduction in risk. To identify safe and effective phytoestrogen candidates for HRT and breast cancer prevention, we investigated the effects of daidzein, genistein, coumestrol, resveratrol and glycitein on cell growth, cell cycle, cyclin D1 expression, apoptosis, Bcl-2/Bax expression ratio and p53-dependent or NF-κB-dependent transcriptional activity in MCF-7 breast cancer cells. Phytoestrogens, except for glycitein, significantly enhanced estrogen-response-element-dependent transcriptional activity up to a level similar to that of 17β-estradiol (E2). E2 increased cell growth significantly, coumestrol increased cell growth moderately, and resveratrol and glycitein reduced cell growth. Phytoestrogens, except for glycitein, stimulated the promotion of cells to G1/S transition in cell cycle analysis, similar to E2. This stimulation was accompanied by transient up-regulation of cyclin D1. While genistein, resveratrol and glycitein all increased apoptosis and reduced the Bcl-2/Bax ratio, resveratrol reduced this ratio more than either genistein or glycitein. Moreover, resveratrol significantly enhanced p53-dependent transcriptional activity, but slightly reduced NF-κB-dependent transcriptional activity. On knockdown analysis, genistein, resveratrol and glycitein all reduced the Bcl-2/Bax ratio in the presence of apoptosis-inducing stimuli, and estrogen receptor (ER) α silencing had no effect on these reductions. In contrast, in the absence of apoptosis-inducing stimuli, only resveratrol reduced the ratio, and ERα silencing abolished this reduction. Thus, resveratrol might be the most promising candidate for HRT and chemoprevention of breast cancer due to its estrogenic activity and high antitumor
activity. (Februari 2010)
