Effect of moderate-intensity treadmill exercise on bone quality in adult rats and the underlying mechanisms

作者：Li C, Gong H, Cen H, Wu X, Wang L, Fan Y · 发表于：BMC musculoskeletal disorders · 年份：2026 · DOI：10.1186/s12891-026-09513-6

BACKGROUND: While exercise is widely recognized to enhance bone mass, the underlying molecular and cellular mechanisms remain incompletely elucidated. The present study was designed to investigate the effect of moderate-intensity exercise on skeletal quality, morphological characteristics, and metabolic homeostasis in adult Sprague-Dawley (SD) rats. METHODS: An animal treadmill exercise model was established using 16-week-old male specific pathogen-free SD rats. Following the 6-week moderate-intensity exercise, bilateral tibiae were harvested for analysis. Body indices of obesity and glucose metabolism were evaluated after the training period. Micro-computed tomography scanning was used to assess three-dimensional bone microarchitecture, while hematoxylin and eosin staining was employed to characterize bone morphological features. RNA sequence and reverse transcription-quantitative PCR identified and validated differentially expressed mRNAs in bone, with bioinformatics analyses predicting their target signaling pathways. Additionally, immunohistochemical staining quantified protein expression of osteogenic, osteoclastic, key pathway and mechanosensitive markers. The apoptosis rate was determined by TdT-mediated dUTP nick end labeling staining. Serum bone turnover markers and inflammatory cytokines were measured after exercise intervention via ELISA kits. RESULTS: Compared with the Control group, exercised rats showed decreasing trends in body weight, Lee’s index, and BMI, wit...