Differential gene expression in triceps brachii muscle with and without unmodulated 40 Hz stimulation in SAMP-10 mice

Unmodulated 40 Hz (u40Hz) stimulation, imperceptible to the human ear, which has been reported to improve cognitive function in human and mice. However, research on the effects of u40Hz stimulation is still limited. This study is the first to report the effects of u40Hz stimulation on glucose tolerance and muscle strength in SAMP-10 mice, an aging-accelerated model. SAMP-10 mice underwent five weeks of u40Hz stimulation, followed by glucose tolerance tests, cognitive and behavioral assessments, and frailty evaluations. Compared to the control group, the u40Hz-stimulated group exhibited mitigated age-related decline in glucose tolerance, a better Frailty Index (FI), and notably preserved muscle strength. Microarray analysis of stimulated muscle tissue revealed significant upregulation of peroxisome proliferator-activated receptor gamma (PPARγ) downstream and β-oxidation genes, and significant downregulation of clock genes. Triceps muscles from 3 SAMP-10 mice after 5 weeks of Unmodulated 40 Hz stimulation and 3 SAMP-10 mice as controls were subjected to microarray.