title: Synergistic effect of isoflavone glycosides and fructooligosaccharides on postgastrectomy osteopenia in rats.
abstract: Fructooligosaccharides stimulate the growth of Bifidobacteria, which cleave isoflavone glycosides to yield corresponding aglycones, and convert metabolites by enhancing enterohepatic recirculation of isoflavones in rats. In the present study, we determined the synergistic effect of dietary isoflavone glycosides and fructooligosaccharides on postgastrectomy osteopenia in rats. Nine-week-old male Sprague-Dawley rats were gastrectomized (n = 20) or sham operated, (control, n = 5) and then randomly assigned to 5 diet groups: sham-a purified diet control, gastrectomized-control, gastrectomized-isoflavone (0.2% isoflavone glycosides), gastrectomized-fructooligosaccharides (7.5% fructooligosaccharides), and isoflavone and fructooligosaccharides (0.2% isoflavone glycosides + 7.5% fructooligosaccharides). After 6 weeks, the rats were killed and biological samples were collected. In gastrectomized rats, fructooligosaccharides prevented femoral bone fragility, but isoflavone without fructooligosaccharides did not inhibit postgastrectomy osteopenia. Isoflavone and fructooligosaccharides exhibited a synergistic in the distal metaphyseal trabecular bone, indicated by peripheral quantitative computed tomography. Moreover, fructooligosaccharides increased calcium absorption and equol production from daidzein in gastrectomized rats. These results indicate that isoflavone alone did not inhibit postgastrectomy osteopenia, but the combination of isoflavone and fructooligosaccharides improved the inhibition of trabecular bone loss by increasing calcium absorption and equol production through fructooligosaccharides supplementation.
authors.affiliation: Department of Nutritional Science, Tokyo University of Agriculture, Tokyo 156-8502, Japan.
authors.forename: Yoshifumi
authors.initials: Y
authors.lastname: Kimira
authors.forename: Kiyono
authors.initials: K
authors.lastname: Tajima
authors.forename: Atsutane
authors.initials: A
authors.lastname: Ohta
authors.forename: Yoshiko
authors.initials: Y
authors.lastname: Ishimi
authors.forename: Shin-Ichi
authors.initials: S
authors.lastname: Katsumata
authors.forename: Kazuharu
authors.initials: K
authors.lastname: Suzuki
authors.forename: Herman
authors.initials: H
authors.lastname: Adlercreutz
authors.forename: Mariko
authors.initials: M
authors.lastname: Uehara