Effect of Rg1-based Supplementation on Exercise Training-induced Stem Cell Recruitments and Skeletal Muscle Adaptation in Women Aged > 60

Background: We have recently observed increased mesenchymal stem cells (Stro-1+ MSCs) in exercised skeletal muscle in women \> 60 years following consumption of a ginseng-derived Rg1-based supplement (Senactiv®). A substantial proportion of these mobilized stem cells differentiated into neural stem cells (Nestin+). Exercise-induced sex hormone depletion is completely attenuated. Together with our earlier finding that Senactiv® reduced perceived exertion during resistance exercise in young men, these results suggest that the supplement may enhance brain-muscle connection/rewiring to improve performance. This acute, single-dose study raises the important question of whether long-term Senactiv® consumption can augment muscle strength and mass in older women engaged in resistance training, a population at high risk of progressing into sarcopenia.

Study Design: To address this, we will conduct a 12-week, two-arm, randomized, double-blind, placebo-controlled trial. Primary and secondary outcomes will include muscle strength, perceived exertion, muscle mass, grip strength and sitting-rising test, sex hormones, Nestin+ neural stem cells, mitochondria-rich phagocytes (MPO-expressing cells), transcriptomic changes (RNA-seq) focusing on age-related biomarkers, bone marrow-derived cells and cognitive function. Skeletal muscle tissue will be analyzed using minimally invasive micro-biopsy at three time points: pre-exercise baseline, immediately after the first exercise bout (0 h, acute response), and 48 hours after the final training session (long-term adaptation). Cognitive function will be comprehensively assessed using available campus resources.