title: Insulinogenic sucrose+amino acid mixture ingestion immediately after resistance exercise has an anabolic effect on bone compared with non-insulinogenic fructose+amino acid mixture in growing rats.
abstract: Maximizing peak bone mass is an important factor in osteoporosis prevention. Resistance exercise increases bone mass and strength, while nutritional supplements have beneficial effects on bone loss reduction. We have previously shown that the combined intake of sucrose and amino acids (AA), which is strongly insulinogenic, efficiently increased muscle protein synthesis. To investigate the effects of sugar and an AA solution immediately after resistance exercise, we compared insulinogenic sucrose and non-insulinogenic fructose combined with an AA solution with or without resistance exercise. Sucrose intake immediately after resistance exercise increased the trabecular bone mass and compressive maximum load compared with fructose+AA intake after exercise. Additionally, combined sucrose+AA and exercise increased trabecular bone formation and decreased bone resorption more than combined fructose and exercise. Serum insulin levels were greatly increased by sucrose+AA intake with exercise. In culture experiments, neither sugar+AA affected osteoblast and osteoclast differentiation. In a gene expression study, sucrose+AA intake after resistance exercise was shown to upregulate the Runx2 expression level and decrease RANKL/OPG ratio. These results suggest that the combined intake of sucrose and an AA solution immediately after resistance exercise exerts anabolic effects on bone by altering gene expression related to bone remodeling. Although translation of our bone remodeling findings from animal to human studies has been challenging, our findings suggest that exercise with sugar+AA intake may contribute to improved bone health.
authors.affiliation: Laboratory and Biochemistry of Exercise and Nutrition, Institute of Health and Sport Sciences, University of Tsukuba, Tsukuba 305-8574, Japan; Department of Molecular Pharmacology, Medical Research Institute, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo, Tokyo 113-8510, Japan; Global Center of Excellence Program for Molecular Science for Tooth and Bone Diseases, Tokyo Medical and Dental University, Tokyo, Japan; Department of Pharmacology, Osaka Dental University, 8-1 Kuzuhahanazono-cho, Hirakata, Osaka 573-1121, Japan. Electronic address: notomph@tmd.ac.jp.
authors.forename: Takuya
authors.initials: T
authors.lastname: Notomi
authors.affiliation: Laboratory and Biochemistry of Exercise and Nutrition, Institute of Health and Sport Sciences, University of Tsukuba, Tsukuba 305-8574, Japan.
authors.forename: Ikuaki
authors.initials: I
authors.lastname: Karasaki
authors.affiliation: Department of Orthopedic Surgery, University of Occupational and Environmental Health, Kitakyushu 807-8555, Japan.
authors.forename: Yuichi
authors.initials: Y
authors.lastname: Okazaki
authors.affiliation: Department of Orthopedic Surgery, University of Occupational and Environmental Health, Kitakyushu 807-8555, Japan.
authors.forename: Nobukazu
authors.initials: N
authors.lastname: Okimoto
authors.affiliation: Laboratory and Biochemistry of Exercise and Nutrition, Institute of Health and Sport Sciences, University of Tsukuba, Tsukuba 305-8574, Japan.
authors.forename: Yushi
authors.initials: Y
authors.lastname: Kato
authors.affiliation: Department of Pharmacology, Osaka Dental University, 8-1 Kuzuhahanazono-cho, Hirakata, Osaka 573-1121, Japan.
authors.forename: Kiyoshi
authors.initials: K
authors.lastname: Ohura
authors.affiliation: Department of Molecular Pharmacology, Medical Research Institute, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo, Tokyo 113-8510, Japan; Global Center of Excellence Program for Molecular Science for Tooth and Bone Diseases, Tokyo Medical and Dental University, Tokyo, Japan.
authors.forename: Masaki
authors.initials: M
authors.lastname: Noda
authors.affiliation: Department of Orthopedic Surgery, University of Occupational and Environmental Health, Kitakyushu 807-8555, Japan.
authors.forename: Toshitaka
authors.initials: T
authors.lastname: Nakamura
authors.affiliation: Laboratory and Biochemistry of Exercise and Nutrition, Institute of Health and Sport Sciences, University of Tsukuba, Tsukuba 305-8574, Japan.
authors.forename: Masashige
authors.initials: M
authors.lastname: Suzuki
mesh_terms: D016475:3T3 Cells; D015502:Absorptiometry, Photon; D000596:Amino Acids / Q000008:administration & dosage*; D000818:Animals; D001483:Base Sequence; D015519:Bone Density; D001842:Bone and Bones / Q000502:physiology*; D017931:DNA Primers; D005632:Fructose / Q000008:administration & dosage*; D007328:Insulin / Q000096:biosynthesis*; D051379:Mice; D010805:Physical Conditioning, Animal; D051381:Rats; D060888:Real-Time Polymerase Chain Reaction; D013395:Sucrose / Q000008:administration & dosage*
chemical_list: D000596:Amino Acids; D017931:DNA Primers; D007328:Insulin; D005632:Fructose; D013395:Sucrose
keywords: Bone formation; Insulin; Mechanical stress