| Budget Amount *help |
¥2,000,000 (Direct Cost: ¥2,000,000)
Fiscal Year 2002: ¥1,200,000 (Direct Cost: ¥1,200,000)
Fiscal Year 2001: ¥800,000 (Direct Cost: ¥800,000)
|
|---|
| Research Abstract |
Soy isoflavones are structurally similar to estrogens and are therefore called phytoestrogens, and may prevent sex hormone-related cancer and osteoporosis. However, few studies regarding the effects of other chemicals on isoflavone bioavailability have been reported. Since almost all phytoestrogens in food exist as glycosides, intestinal bacteria glucosidases are required to hydrolyze the glycosidic bonds to enable intestinal absorption. Fructooligosaceharides (FOS), a mixture of indigestible and fermentable sugars, stimulate the growth of bifidobacteria in the intestine. Thus, it is postulated that dietary FOS may affect the bioavailability of phytoestrogen glycosides and therefore improve their absorption in the gut, thus having beneficial effects on lifestyle-related diseases.
In 2001, the kinetics of isoflavones in rats fed a FOS supplemented diet or a control diet were examined by measuring genistein and daidzein concentrations in blood collected from three different veins, and by
… More
measuring urinary excretion at 24-and 48-hours after a single intragastric ministration of isoflavone conjugates. The genistein concentration in the portal blood increased rapidly, reaching a peak in both FOS and control groups at 1h after administration. The concentrations in the central venous blood were approximately half of those in the portal blood. In the FOS fed group, both genistein and daidzein remained detectable in the tail venous blood after 24-48 hours. The urinary excretion of both isoflavones at 24-and 48-hours after administration was significantly higher in the FOS-fed group than in the control gloup.
In 2002, the synergistic effects of dietary isoflavone and FOS supplementation on post-gastrectomy (OX) osteopenia and anemia were determined. Decreases in femoral trabecular bone mineral density and bone breaking force by OX were inhibited in rats fed the FOS with and without isoflavone diets, whereas isoflavone only supplementation did not prevent bone loss in OX rats. Notably, a combination isoflavone and FOS diet enhanced production of equol, which has a strong estrogenic effect, from daidzein in OX rats. Moreover, both isoflavone and FOS supplementations prevented increases of hepatic lipid hydroperoxides and serum TNF-α, a marker of tissue necrosis, in post-OX anemic rats. Less
|
