New Strains of and are Effective for Improving the Muscle Strength of Mice with Immobilization-Induced Muscular Atrophy.

Muscular atrophy is a muscle disease in which muscle mass and strength decrease due to aging, injury, metabolic disorders, or chronic conditions. Proteins in muscle tissue are degraded by the ubiquitin-proteasome pathway, and atrophy accelerates this pathway. and strains are effective agents against metabolic and inflammatory diseases in next-generation probiotic research. In this study, we evaluated the efficacy of strain EB-AMDK19 and strain EB-FPDK11 in a mouse model of muscular atrophy, since atrophy inhibits energy metabolism and immune activation. After oral administration of each strain for 4 weeks, the hind legs of the mice were fixed with a plaster cast to immobilize them for a week. As a result, the administration of EB-AMDK19 and EB-FPDK11 strains improved grip strength but did not increase muscle mass. At the molecular level, and treatments decreased the expression levels of ubiquitin-proteasome genes, , , and . They increased the expression level of the mitochondrial biogenesis regulatory gene, . The effect of the strains was confirmed by a decrease in myostatin. Furthermore, and modulated the immune function by enhancing and inhibiting . In particular, EB-AMDK19 promoted the expression of , an anti-inflammatory cytokine. These results suggest that and may have beneficial effects on muscular atrophy, verified by newly isolated EB-AMDK19 and EB-FPDK11 as potential next-generation probiotics.