Protective effects of hydrolyzed Gryllus bimaculatus extract on dexamethasone-induced sarcopenia in C57BL/6 mice

This study aimed to evaluate the protective effects of hydrolyzed Gryllus bimaculatus extract (GBE) against dexamethasone (DEX)-induced sarcopenia in C57BL/6 mice. Muscle atrophy was induced by intraperitoneal injection of DEX (20 mg/kg/day) for 10 consecutive days (Day 3–12). GBE (100 or 200 mg/kg/day) was administered orally starting 2 days before DEX treatment and continued for 12 days (Day 1–12). GBE significantly attenuated DEX-induced reductions in body weight and muscle mass. Furthermore, GBE administration upregulated the expression of muscle regeneration–related factors, including IGF-1, mTOR, MyoD, MYF5, and MYF6, while downregulating muscle atrophy markers such as myostatin, FOXO3a, MuRF1, and MAFbx. In addition, GBE enhanced antioxidant enzyme activities and suppressed pro-inflammatory cytokines including IL-6 and TNF-α. These findings suggest that GBE may serve as a promising functional ingredient to prevent glucocorticoid-induced muscle atrophy and may offer therapeutic potential for the management of muscle wasting conditions.