title: Dietary xylitol protects against the imbalance in bone metabolism during the early phase of collagen type II-induced arthritis in dark agouti rats.
abstract: The aim of the present study was to evaluate the changes in bone metabolism during the early phase of type II collagen-induced arthritis in rats and to evaluate whether a 10% dietary xylitol supplementation is able to protect against these changes. Arthritis was induced in female dark agouti rats by injections of type II homologous rat collagen emulsified with an equal volume of incomplete Freund adjuvant. In one group, the diet was supplemented with 10% xylitol. After 17 days, the rats were killed. Serum osteocalcin, as a marker of bone formation, and serum tartrate-resistant acid phosphatase, as a marker of bone resorption, were measured. Histologic measurements were made from Masson-Goldner trichrome-stained sections of distal tibiae. All the collagen-injected rats had arthritic symptoms at the end of the experiment. Serum osteocalcin was significantly higher in the collagen-injected rats fed a xylitol-supplemented diet (CI-X) than in the collagen-injected rats not fed xylitol (CI) and in the controls. Serum tartrate-resistant acid phosphatase was significantly higher in the CI and CI-X groups than in the controls. Trabecular bone volume was significantly lower in the CI group as compared with the CI-X and control groups. These results suggest that, at the time of the appearance of arthritic symptoms, bone resorption activity is high, but bone formation is not severely affected. Furthermore, dietary xylitol seems to protect against the imbalance of bone metabolism during the early phase of collagen type II-induced arthritis.
authors.affiliation: Institute of Dentistry, University of Oulu, Oulu, Finland.
authors.forename: Sirpa M
authors.initials: SM
authors.lastname: Kaivosoja
authors.forename: Pauli T
authors.initials: PT
authors.lastname: Mattila
authors.forename: Matti L E
authors.initials: ML
authors.lastname: Knuuttila
mesh_terms: D000135:Acid Phosphatase / Q000097:blood / Q000378:metabolism; D000818:Animals; D001169:Arthritis, Experimental / Q000097:blood / Q000378:metabolism*; D001835:Body Weight / Q000187:drug effects; D016723:Bone Remodeling / Q000187:drug effects*; D001842:Bone and Bones / Q000187:drug effects / Q000378:metabolism*; D004435:Eating / Q000187:drug effects; D005260:Female; D006651:Histocytochemistry; D015675:Osteocalcin / Q000097:blood; D051381:Rats; D013977:Tibia / Q000473:pathology; D014993:Xylitol / Q000494:pharmacology*
chemical_list: D015675:Osteocalcin; D000135:Acid Phosphatase; D014993:Xylitol