title: Biomechanical and microstructural benefits of physical exercise associated with risedronate in bones of ovariectomized rats.
abstract: Several treatments have been developed aiming the prevention of bone loss. There are discussions about the best prophylactic and therapeutic procedures for osteoporosis. This study evaluated the effects of physical exercise associated with risedronate as a prophylactic and therapeutic procedure in osteopenic bones of rats submitted to ovariectomy. We used 48 Wistar rats divided into: ovariectomized or subjected to sham surgery. Ovariectomized rats were divided into the following sub-groups: OVX, 12 weeks sedentary; OVX-EX, treadmill training for 12 weeks; OVX-RA, 12 weeks with risedronate administration; and OVX-EX-RA, 12 weeks with risedronate administration and treadmill training. Rats subjected to sham surgery were divided into the following sub-groups: SH, 12 weeks sedentary; SH-EX, treadmill training for 12 weeks; SH-RA, 12 weeks with risedronate administration; and SH-EX-RA, 12 weeks with risedronate administration and training on the treadmill. The effectiveness of the treatment was evaluated in tibias using biomechanical, radiological, histomorphometric, and immunohistochemical analyses. Data were analyzed by statistical tests, with significance level of P < 0.05. Results of mechanical tests showed that the SH-RA group had lower values compared with OVX-RA group; densitometry showed no significant differences; according to histomorphometric methods, OVX group presented lower results than the SH-EX, OVX-RA, SH-EX-RA, and OVX-EX-RA groups, and SH-EX-RA and OVX-EX-RA groups showed values higher than SH-RA, SH, and OVX-EX groups. The SH-EX-RA and OVX-EX-RA groups had decreased immunostaining for tartrate-resistant acid phosphatase and receptor activator of nuclear factor kappa-B ligand and increased osteoprotegerin immunostaining. In this experimental model, it was concluded that the physical training associated with use of risedronate exerted positive effects on biomechanical and microstructural properties in bones of ovariectomized rats.
authors.affiliation: Department of Biomechanics, Medicine and Locomotor Apparatus Rehabilitation, Faculty of Medicine, University of São Paulo, São Paulo, Brazil.
authors.forename: Roberta Carminati
authors.initials: RC
authors.lastname: Shimano
authors.forename: Ana Paula
authors.initials: AP
authors.lastname: Macedo
authors.forename: Maurício José
authors.initials: MJ
authors.lastname: Falcai
authors.forename: Edilson
authors.initials: E
authors.lastname: Ervolino
authors.forename: Antônio Carlos
authors.initials: AC
authors.lastname: Shimano
authors.forename: João Paulo Mardegan
authors.initials: JP
authors.lastname: Issa
mesh_terms: D000818:Animals; D001696:Biomechanical Phenomena; D015519:Bone Density / Q000187:drug effects; D050071:Bone Density Conservation Agents / Q000627:therapeutic use*; D001842:Bone and Bones / Q000187:drug effects / Q000648:ultrastructure*; D012968:Etidronic Acid / Q000031:analogs & derivatives* / Q000627:therapeutic use; D005081:Exercise Therapy; D005260:Female; D010024:Osteoporosis / Q000473:pathology / Q000517:prevention & control*; D010052:Ovariectomy; D051381:Rats; D017208:Rats, Wistar; D000068296:Risedronic Acid
chemical_list: D050071:Bone Density Conservation Agents; D000068296:Risedronic Acid; D012968:Etidronic Acid
keywords: bone diseases; medicine; metabolic; microscopy; physical exercise