title: Effects of hyperglycemia on bone metabolism and bone matrix in goldfish scales.
abstract: Increased risk of fracture associated with type 2 diabetes has been a topic of recent concern. Fracture risk is related to a decrease in bone strength, which can be affected by bone metabolism and the quality of the bone. To investigate the cause of the increased fracture rate in patients with diabetes through analyses of bone metabolism and bone matrix protein properties, we used goldfish scales as a bone model for hyperglycemia. Using the scales of seven alloxan-treated and seven vehicle-treated control goldfish, we assessed bone metabolism by analyzing the activity of marker enzymes and mRNA expression of marker genes, and we measured the change in molecular weight of scale matrix proteins with SDS-PAGE. After only a 2-week exposure to hyperglycemia, the molecular weight of α- and β-fractions of bone matrix collagen proteins changed incrementally in the regenerating scales of hyperglycemic goldfish compared with those of euglycemic goldfish. In addition, the relative ratio of the γ-fraction significantly increased, and a δ-fraction appeared after adding glyceraldehyde-a candidate for the formation of advanced glycation end products in diabetes-to isolated type 1 collagen in vitro. The enzymatic activity and mRNA expression of osteoblast and osteoclast markers were not significantly different between hyperglycemic and euglycemic goldfish scales. These results indicate that hyperglycemia is likely to affect bone quality through glycation of matrix collagen from an early stage of hyperglycemia. Therefore, non-enzymatic glycation of collagen fibers in bone matrix may lead to the deterioration of bone quality from the onset of diabetes.
authors.affiliation: Department of Clinical Laboratory Science, Graduate School of Medical Science, Kanazawa University, Kanazawa, Ishikawa 920-0942, Japan. Electronic address: kkitamur@staff.kanazawa-u.ac.jp.
authors.forename: Kei-Ichiro
authors.initials: KI
authors.lastname: Kitamura
authors.affiliation: Seikai National Fisheries Research Institute, Japan Fisheries Research and Education Agency, Nagasaki-shi, Nagasaki 851-2213, Japan.
authors.forename: Tadashi
authors.initials: T
authors.lastname: Andoh
authors.affiliation: Department of Clinical Laboratory Science, Graduate School of Medical Science, Kanazawa University, Kanazawa, Ishikawa 920-0942, Japan.
authors.forename: Wakana
authors.initials: W
authors.lastname: Okesaku
authors.affiliation: Department of Clinical Laboratory Science, Graduate School of Medical Science, Kanazawa University, Kanazawa, Ishikawa 920-0942, Japan.
authors.forename: Yuya
authors.initials: Y
authors.lastname: Tazaki
authors.affiliation: Wellness Promotion Science Center, Institute of Medical, Pharmaceutical and Health Sciences, Kanazawa University, Kanazawa, Ishikawa 920-0942, Japan.
authors.forename: Kazuhiro
authors.initials: K
authors.lastname: Ogai
authors.affiliation: Department of Clinical Laboratory Science, Graduate School of Medical Science, Kanazawa University, Kanazawa, Ishikawa 920-0942, Japan.
authors.forename: Kayo
authors.initials: K
authors.lastname: Sugitani
authors.affiliation: Faculty of Natural System, Institute of Science and Engineering, Kanazawa University, Kanazawa, Ishikawa 920-1192, Japan.
authors.forename: Isao
authors.initials: I
authors.lastname: Kobayashi
authors.affiliation: Noto Marine Laboratory, Institute of Nature and Environmental Technology, Kanazawa University, Noto-cho, Ishikawa 927-0553, Japan.
authors.forename: Nobuo
authors.initials: N
authors.lastname: Suzuki
authors.affiliation: Biomedical Information Technology Laboratory, Graduate Department of Computer and Information System, The University of Aizu, Aizuwakamatsu, Fukushima 965-8580, Japan.
authors.forename: Wenxi
authors.initials: W
authors.lastname: Chen
authors.affiliation: Department of Oral Morphology, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, Okayama, Okayama 700-8525, Japan.
authors.forename: Mika
authors.initials: M
authors.lastname: Ikegame
authors.affiliation: Department of Biology, College of Liberal Arts and Sciences, Tokyo Medical and Dental University, Ichikawa, Chiba 272-0827, Japan.
authors.forename: Atsuhiko
authors.initials: A
authors.lastname: Hattori
mesh_terms: D000496:Alloxan / Q000008:administration & dosage; D000818:Animals; D001786:Blood Glucose / Q000378:metabolism; D001842:Bone and Bones / Q000378:metabolism*; D004591:Electrophoresis, Polyacrylamide Gel; D006054:Goldfish; D006943:Hyperglycemia / Q000378:metabolism*
chemical_list: D001786:Blood Glucose; D000496:Alloxan
keywords: Alloxan; Bone metabolism; Bone model; Diabetes; Fish scales; Glycation of matrix collagen; Hyperglycemia; Increased fracture rate; Type 1 collagen