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.

Influence of treadmill training on bone structure under osteometabolic alteration in rats subjected to high‐fat diet

“…When evaluating the trabecular bone area in the proximal tibia, we found lower values associated with OVX animals compared to SHAM animals. These results suggest that the estrogen deficit caused a reduction in bone trabecular density (Ito et al., ; Shimano et al., ). The proposed physical exercise increased the trabecular bone microarchitecture.…”

“…(), osteopenia manifests in a period of 30–60 days after ovariectomy. The training of animals began 72 h after ovariectomy so it could begin before osteopenia onset (Simões et al., ; Shimano et al., ). The same procedure was applied to the trained SHAM animals.…”

“…Obesity, often resulting from unbalanced diets, has been currently associated with the increased incidence of low‐impact fractures in post‐menopausal female population (Shimano et al., ). Proper nutrition plays an important role in the accumulation and maintenance of bone mass and it has been shown as an important tool for the prevention of fractures in people with osteoporosis (Pinheiro et al., ).…”

Effects of high‐impact exercise on the physical properties of bones of ovariectomized rats fed to a high‐protein diet

“…In general, an ideal diet is not sufficient to supply the hormonal deficit caused by menopause, especially regarding bone tissue. Physical exercises are considered a good strategy for maintaining bone mass; however, although the effectiveness of different types of exercise has already been widely discussed, there is a significant gap on the ideal modality …”

“…At menopause, bone mineral density (BMD) declines rapidly resulting from estrogen deficiency declines, increasing the risk of women developing osteoporosis. In addition to a balanced diet, with the aim of treatment and prevention, physical exercise is exploited by its low cost and lack of side effects compared to drug treatments …”