Fermented Tenebrio molitor larvae extract with Lactobacillus plantarum ameliorates dexamethasone-induced muscle atrophy in vitro and in vivo

Sarcopenia, characterized by progressive age-related declines in skeletal muscle mass and function, is exacerbated by inadequate protein intake in elderly populations. This study aimed to evaluate the effects of fermented Tenebrio molitor with Lactobacillus plantarum as a sustainable protein supplement against dexamethasone-induced myotube atrophy in C2C12 myoblasts and muscle atrophy in a C57BL/6 mouse model. We evaluated the effect of Tenebrio molitor with Lactobacillus plantarum using various methods, including immunofluorescence staining, Western blot, quantitative polymerase chain reaction, exercise performance measurement, and muscle tissue analysis. The results showed that Tenebrio molitor with Lactobacillus plantarum treatment significantly improved myotube area, myotube diameter, expression of myogenin and myosin heavy chain in dexamethasone-induced C2C12 myotubes. In addition, Tenebrio molitor with Lactobacillus plantarum enhanced the expression of myogenic regulatory factors, such as myogenic factor 5 and myogenin and reduced the expression of protein degradation marker, including atrogin-1, muscle really interesting new gene finger protein-1, and myostatin in the myotubes. In dexamethasone-treated mice, Tenebrio molitor with Lactobacillus plantarum increased exercise capacity and muscle weight, while inhibiting myosin heavy chain and muscle atrophy markers’ expression. These findings highlight the potential of Tenebrio molitor with Lactobacillus plantarum as a sustainable protein source for managing sarcopenia by preserving muscle mass and improving physical function, suggesting it as a potential therapeutic agent for treating muscle weakness and atrophy in aging populations.