title: The combined effects of soya isoflavones and resistant starch on equol production and trabecular bone loss in ovariectomised mice.
abstract: Equol is a metabolite of the soya isoflavone (ISO) daidzein that is produced by intestinal microbiota. Equol has greater oestrogenic activity compared with other ISO, and it prevents bone loss in postmenopausal women. Resistant starch (RS), which has a prebiotic activity and is a dietary fibre, was reported to promote equol production. Conversely, the intestinal microbiota is reported to directly regulate bone health by reducing inflammatory cytokine levels and T-lymphocytes in bone. The present study evaluated the combined effects of diet supplemented with ISO and RS on intestinal microbiota, equol production, bone mineral density (BMD) and inflammatory gene expression in the bone marrow of ovariectomised (OVX) mice. Female ddY strain mice, aged 8 weeks, were either sham-operated (Sham, n 7) or OVX. OVX mice were randomly divided into the following four groups (seven per group): OVX control (OVX); OVX fed 0·05 % ISO diet (OVX+ISO); OVX fed 9 % RS diet (OVX+RS); and OVX fed 0·05 % ISO- and 9 % RS diet (OVX+ISO+RS). After 6 weeks, treatment with the combination of ISO and RS increased equol production, prevented the OVX-induced decline in trabecular BMD in the distal femur by modulating the enteric environment and altered OVX-induced inflammation-related gene expression in the bone marrow. However, there were no significant differences in bone parameters between the ISO+RS and ISO-alone groups in OVX mice. Our findings suggest that the combination of ISO and RS might alter intestinal microbiota and immune status in the bone marrow, resulting in attenuated bone resorption in OVX mice.
authors.affiliation: 1Department of Food Function and Labeling,National Institute of Health and Nutrition,National Institutes of Biomedical Innovation, Health and Nutrition,1-23-1 Toyama,Shinjuku-ku,Tokyo 162-8636,Japan.
authors.forename: Yuko
authors.initials: Y
authors.lastname: Tousen
authors.affiliation: 1Department of Food Function and Labeling,National Institute of Health and Nutrition,National Institutes of Biomedical Innovation, Health and Nutrition,1-23-1 Toyama,Shinjuku-ku,Tokyo 162-8636,Japan.
authors.forename: Yu
authors.initials: Y
authors.lastname: Matsumoto
authors.affiliation: 1Department of Food Function and Labeling,National Institute of Health and Nutrition,National Institutes of Biomedical Innovation, Health and Nutrition,1-23-1 Toyama,Shinjuku-ku,Tokyo 162-8636,Japan.
authors.forename: Chiho
authors.initials: C
authors.lastname: Matsumoto
authors.affiliation: 1Department of Food Function and Labeling,National Institute of Health and Nutrition,National Institutes of Biomedical Innovation, Health and Nutrition,1-23-1 Toyama,Shinjuku-ku,Tokyo 162-8636,Japan.
authors.forename: Yoriko
authors.initials: Y
authors.lastname: Nishide
authors.affiliation: 3Product Development Laboratory,J-OIL MILLS,Inc.,11 Kagetoricho,Totsuka-ku,Yokohama,Kanagawa 245-0064,Japan.
authors.forename: Yuya
authors.initials: Y
authors.lastname: Nagahata
authors.affiliation: 3Product Development Laboratory,J-OIL MILLS,Inc.,11 Kagetoricho,Totsuka-ku,Yokohama,Kanagawa 245-0064,Japan.
authors.forename: Isao
authors.initials: I
authors.lastname: Kobayashi
authors.affiliation: 1Department of Food Function and Labeling,National Institute of Health and Nutrition,National Institutes of Biomedical Innovation, Health and Nutrition,1-23-1 Toyama,Shinjuku-ku,Tokyo 162-8636,Japan.
authors.forename: Yoshiko
authors.initials: Y
authors.lastname: Ishimi
mesh_terms: D000818:Animals; D015519:Bone Density / Q000187:drug effects*; D001853:Bone Marrow / Q000378:metabolism; D001862:Bone Resorption / Q000188:drug therapy / Q000378:metabolism / Q000382:microbiology / Q000473:pathology; D004043:Dietary Fiber / Q000494:pharmacology; D019587:Dietary Supplements; D060754:Equol / Q000096:biosynthesis*; D005260:Female; D005269:Femur / Q000187:drug effects* / Q000378:metabolism / Q000473:pathology; D000069196:Gastrointestinal Microbiome / Q000187:drug effects; D007249:Inflammation / Q000235:genetics / Q000378:metabolism / Q000517:prevention & control; D007529:Isoflavones / Q000494:pharmacology* / Q000627:therapeutic use; D051379:Mice; D010052:Ovariectomy; D010936:Plant Extracts / Q000494:pharmacology / Q000627:therapeutic use; D056692:Prebiotics; D011897:Random Allocation; D013025:Glycine max / Q000737:chemistry*; D013213:Starch / Q000494:pharmacology*
chemical_list: D004043:Dietary Fiber; D007529:Isoflavones; D010936:Plant Extracts; D056692:Prebiotics; D060754:Equol; C004742:daidzein; D013213:Starch
keywords: BMD bone mineral density; Bones; CD40L CD-40-ligand; HAS high-amylose maize starch; ISO isoflavone; Intestinal microbiota; OVX ovariectomised mice; Osteoporosis; RS resistant starch; Resistant starch; Soya isoflavones