The influence of long-term treadmill exercise on bone mass and articular cartilage in ovariectomized rats

Abstract

BackgroundLoss of bone quality and deterioration of articular cartilage are commonly seen after menopause. While exercise may protect against tissue degeneration, a clear link has yet to be established. The aim of the present study is to investigate the influence of long-term treadmill exercise on changes in bone mass and articular cartilage in ovariectomized rats.MethodsSixty female Sprague-Dawley rats were randomly assigned to 4 groups: ovariectomized (OVX), ovariectomized plus treadmill exercise (OVX-RUN), treadmill exercise alone (RUN), and control (CON) groups. After 36 weeks, the following variables were compared among the 4 groups. Bone mass was evaluated by trabecular bone volume and bone mineral density (BMD). Articular cartilage in the knee joints was evaluated by histology analysis and a modified Mankin score.ResultsRats in the ovariectomized groups (OVX and OVX-RUN) had significantly lower BMD and bone mass than the non-ovariectomized rats (CON and RUN), indicating that exercise did little to preserve bone mass. However, the sedentary OVX group had a significantly worse modified Mankin score (7.7 ± 1.4) than the OVX-RUN group (4.8 ± 1.0), whose scores did not differ significantly from the other 2 non-operated groups. The articular cartilage in the sedentary OVX rats was relatively thinner, hypocellular, and had more clefts than in the other 3 groups.ConclusionThis study suggests that long-term exercise protects articular cartilage in OVX rats but does not retard the loss of bone mass seen in after menopause.

Histomorphometric evaluation of tibial subchondral bone after moderate running in male and female Wistar rats

“…This finding might be attributed to the position of tibia and mechanical loading on the tibia during treadmill running (Iwamoto et al, 2011;Mosavian 2017). Moreover, Chang et al (2010) showed that the cancellous bone response to exercise changes relative to the bone mechanical loading. This finding is consistent with a previous study, which indicated the positive site-specific effect of treadmill exercise on BMD, with predominant weight-bearing sites (Iwamoto et al 2011).…”

“…Serial longitudinal sections were cut with a rotary microtome and mounted on saline-coated slides glass after preparation of histological specimens. Before staining, the sections were deparaffinized in 100% xylene and rehydrated in graded ethanol (Chang et al, 2010). The longitudinal sections of the proximal tibia, between medial and lateral intercondyloid spines, and transvers sections of the mid shaft of tibia were cut at 5-µm thickness with a microtome.…”

“…The histomorphometric parameters evaluated for tibial shaft were total tissue area (Tt Ar), marrow cavity area (Mc Ar) and cortical bone area (Cb Ar). These parameters were chosen based on a previous study (Chang et al, 2010). The results were obtained by using an Olympus light microscope and an attached eyepiece digital lens (Dino-eye, AM-7023, 5Mp, Taiwan).…”

Análise termogravimétrica da cartilagem articular de ratos exercitados após imobilização

“…Del Carlo et al 23 realizaram um estudo com ratos imobilizados por 45 dias e remobilizados livre e por meio de exercício físico, no qual os animais que realizaram natação demonstraram quadro menos severo de lesão no tecido cartilaginoso, demonstrada por análise histológi-ca. Chang et al 24 evidenciaram que o exercício físico promove uma proteção aos condrócitos mesmo em ratas que foram submetidas à ovariectomia, condição que pode acelerar o processo de degeneração da cartilagem, mantendo assim sua integridade estrutural.…”

Human Placenta Hydrolyzates in Reconstructive Therapy of Connective Tissue of Cartilage and Joints

“…Для этого образцы фиксировали в 10% растворе нейтрального формалина, декальцинировали и заливали в парафин. Критериями гистологической оценки служили изменения околосустав-ного аппарата, наличие воспалительного инфильтрата, состояние суставного хряща и костной ткани [29]. Состояние хряща по каждому из этих критериев оценивали в баллах так, что при максимальной выраженности патологического Окрашивание гематоксиллином и эозином…”