Pulsed ultrasound restores gut microbiota and recovers muscle mass in aging

Low-intensity pulsed ultrasound directed at the abdomen reversed sarcopenia-like characteristics in 92-week-old mice, significantly improving forelimb and hind limb grip strength after eight weeks of treatment. The study, conducted with six animals per group, documented how ultrasonic stimulation suppressed key inflammatory markers—COX-2, phosphorylated NF-κB, NLRP3, IL-1β, and Caspase-1—that had proliferated due to age-related renal impairment and advanced glycation end product accumulation. Microbiota analysis revealed that treatment enriched anti-inflammatory taxa including Lactobacillus, Bifidobacterium, and Faecalibaculum, increasing overall microbial diversity. These organisms showed direct positive correlation with improved muscle performance. While the exact mechanism by which ultrasound modifies bacterial composition remains unclear, the finding suggests a potentially noninvasive therapeutic route relevant to muscle longevity strategies in humans, complementing approaches like fecal microbiota transplantation from young donors that require years of clinical follow-up.