Lentinan mitigates age-related sarcopenia through the promotion of mitochondrial biogenesis

Previous epidemiological evidence has indicated that mushroom intake may reduce sarcopenia risk in older adults, though this is unconfirmed by laboratory studies. Here, we examined whether lentinan (LNT), a mushroom polysaccharide, influences C2C12 myoblast differentiation and attenuates age-related muscle atrophy in aged mice. In vitro, LNT significantly enhanced C2C12 differentiation, increasing myotube diameter and myogenic differentiation 1 (MyoD1)/myogenin expression. In vivo, LNT treatment enhanced grip strength and exercise endurance in naturally aging mice while also slowing muscle mass and cross-sectional area loss. Transmission electron microscopy analysis revealed that low and medium doses of LNT significantly increased mitochondrial abundance and improved mitochondrial morphology in both differentiated C2C12 and skeletal muscle tissues. Furthermore, the expression intensities of crucial proteins participating in mitochondrial biogenesis (PGC-1α, Nrf2, and TFAM) were significantly upregulated in cell samples. These results indicate that LNT may mitigate sarcopenia through activating the PGC-1α/Nrf2/TFAM and promoting mitochondrial biogenesis.