Transcriptional Profiling of Muscle in Females with Distal Radius Fracture and Functional Sarcopenia.

Skeletal muscle and bone interact with each other via mechanical and biochemical ways. This study aimed to investigate the molecular mechanisms of interaction between muscle and bone and by analyzing the transcriptional profiles of total RNA from muscle tissue of females with distal radius fractures. A total 30 female participants (mean age 71.1 ± 8.9 years) with distal radius fractures were recruited. Participants were categorized into two groups; the NORM group consisted of participants with T score of the areal bone mineral density (aBMD) of the femoral neck higher than -1.0, handgrip strength greater than 18 kg, and gait speed faster than 1.0 m/sec (n = 10). Otherwise, participants with T score of the aBMD of the femoral neck equal or less than -1.0, handgrip strength lower than 18 kg, and gait speed slower than 1.0 m/sec (n = 20) were categorized into EXP group. Pronator quadratus muscle samples were obtained from all participants. Total RNA was extracted from frozen muscle samples and sequenced. The gene ontology analysis demonstrated that the potential interactions between attached muscle function and density of the associated bone would be linked with collagen biosynthetic activity, and maintenance of extracellular matrix structures. The analysis of the pathway, network, and protein class exhibited that integrin signaling, inflammatory reactions, matrix metalloproteinase (MMP) activity, and extracellular matrix protein structure had possible associations with the molecular background of muscle-bone interaction. Through integrin signaling, MMP activity, inflammatory reactions, and collagen biosynthesis, muscle and bone may mutually interact with one another.