Does genotype and equol-production status affect response to isoflavones? Data from a pan-European study on the effects of isoflavones on cardiovascular risk markers in post-menopausal women.

摘要

The increase in cardiovascular disease (CVD) incidence following the menopause is associated with oestrogen loss. Dietary isoflavones are thought to be cardioprotective via their oestrogenic and oestrogen receptor-independent effects, but evidence to support this role is scarce. Individual variation in response to diet may be considerable and can obscure potential beneficial effects in a sample population; in particular, the response to isoflavone treatment may vary according to genotype and equol-production status. Therefore, effects of soy isoflavone supplementation on a range of established and novel biomarkers of CVD, including markers of lipid and glucose metabolism and inflammatory biomarkers, were investigated in a placebo-controlled 2x 8-wk randomized cross-over study in 117 healthy postmenopausal women. Responsiveness to soy isoflavone supplementation (50 mg/day; Solgen 40 containing genistein and daidzein at a ratio of 2:1 incorporated into cereal bars) was examined with respect to: single nucleotide polymorphisms in a range of key CVD genes, including oestrogen receptor (ER) alpha and beta; and equol-production status. Isoflavones supplementation was found to have no effect on markers of lipids and glucose metabolism. Isoflavones improved C-reactive protein concn. but dido not affect other plasma inflammatory markers. There were no differences in response to isoflavones according to equol-production status. However, differences in high density lipoprotein (HDL)-cholesterol and vascular cell adhesion molecule 1 response to isoflavones vs. placebo were evident with specific ERbeta genotypes. In conclusion, isoflavones have beneficial effects on C-reactive protein, but not other cardiovascular risk markers. However, specific ERbeta gene polymorphic subgroups may benefit from isoflavone supplementation. [This paper was presented at the Summer Meeting of the Nutrition Society held in Norwich, UK, from 28 June to 1 July, 2005.]