Oligo fucoidan alleviates sarcopenia via attenuating muscle mass loss and function decline in senescence-accelerated mouse prone 8 mice

Objective: Sarcopenia, the progressive loss of skeletal muscle mass and function with age, presents a significant health challenge for older adults. Fucoidan, a bioactive polysaccharide from brown seaweed, has attracted attention for its physiological benefits. We aimed to evaluate the potential of oligo fucoidan (OliFuco) as a nutritional intervention to mitigate sarcopenia. Method: We assessed senescence-associated β-galactosidase activity and myotube formation in senescent C2C12 myoblasts with or without OliFuco treatment. In senescence-accelerated mouse-prone 8 (SAMP8) mice, an in vivo model of sarcopenia, OliFuco was administered from the asymptomatic stage (preventive model) or the pre-sarcopenia stage (treatment model). We evaluated muscle mass, strength, histology, inflammatory cytokines, and key molecular pathways. Results: OliFuco delayed cellular senescence and improved myotube formation in C2C12 myoblasts. In vivo, OliFuco significantly increased muscle mass, strength, and myofiber cross-sectional area in SAMP8 mice, particularly in the preventive model. OliFuco promoted protein synthesis through AKT/mTOR/p70sk6 up-regulation, inhibited protein degradation via FoxO1/MuRF1 down-regulation, and reduced pro-inflammatory cytokines IL-6, TNF-α, and myostatin by suppressing NF-κB. Compared with branched-chain amino acids, a well-known nutritional supplement for stimulating muscle protein synthesis, OliFuco was more effective in ameliorating sarcopenia in SAMP8 mice. OliFuco alleviates sarcopenia by delaying cellular senescence, supporting positive muscle protein turnover, and reducing chronic inflammation during aging. Conclusion: Our findings show that OliFuco is a promising nutritional intervention for mitigating sarcopenia by preserving muscle mass and function in aging populations, offering a novel strategy to address age-related muscle decline.