title: RANKL is downregulated in bone cells by physical activity (treadmill and vibration stimulation training) in rat with glucocorticoid-induced osteoporosis.
abstract: The aim of this study was to investigate bone tissue and plasma levels of RANKL and OPG in rats with prednisolone-induced osteoporosis and to evaluate the outcomes of physical activity on the skeletal system by treadmill and vibration platform training. Osteoporosis is a disease characterised by low bone mass and structural deterioration of bone tissue leading to bone fragility. Vibration exercise is a new and effective measure to prevent muscular atrophy and osteoporosis. The animals were divided into 5 groups. 1: control rats; 2: rats with osteoporosis receiving prednisolone; 3: rats receiving prednisolone and treadmill training; 4: rats receiving prednisolone and vibration stimulation training; 5: rats receiving prednisolone, treadmill and vibration stimulation training. For bone evaluations we used whole-body scans, histology and histomorphometric analysis. RANKL and OPG expression was evaluated by immunohistochemistry and biochemical analysis. After treatment, our data demonstrated that RANKL expression was significantly increased in groups 2 and 3 and decreased in groups 4 and 5. Conversely, OPG expression was significantly decreased in groups 2 and 3 and increased in groups 4 and 5. In conclusion, our findings suggest that mechanical stimulation inhibits the activity of RANKL. This finding provides new insights into the occurrence and progression of osteoporosis.
authors.affiliation: Department of Pediatric and Adolescent Surgery, Medical University of Graz, Austria.
authors.forename: Karin
authors.initials: K
authors.lastname: Pichler
authors.forename: Carla
authors.initials: C
authors.lastname: Loreto
authors.forename: Rosalia
authors.initials: R
authors.lastname: Leonardi
authors.forename: Tobias
authors.initials: T
authors.lastname: Reuber
authors.forename: Annelie Martina
authors.initials: AM
authors.lastname: Weinberg
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Musumeci
mesh_terms: D000818:Animals; D001823:Body Composition; D001835:Body Weight; D015519:Bone Density; D018450:Disease Progression; D015536:Down-Regulation; D005938:Glucocorticoids / Q000009:adverse effects*; D007150:Immunohistochemistry; D008297:Male; D010024:Osteoporosis / Q000139:chemically induced / Q000378:metabolism*; D053244:Osteoprotegerin / Q000378:metabolism; D010805:Physical Conditioning, Animal; D053245:RANK Ligand / Q000378:metabolism*; D051381:Rats; D017208:Rats, Wistar; D014732:Vibration
chemical_list: D005938:Glucocorticoids; D053244:Osteoprotegerin; D053245:RANK Ligand; C506032:Tnfrsf11b protein, rat