Centella asiatica, Daucus carota, and Brassica oleracea Extracts Protect Against Dexamethasone-Induced Muscle Atrophy Through the Activation of the AKT/mTOR Pathway.

Abstract

Degenerative muscle atrophy leads to reduced muscle mass, strength, and function, increasing the risk of falls and impairing quality of life. While plant-derived compounds possess anti-inflammatory and antioxidant properties, their capacity to mitigate muscle atrophy has not been fully explored. This study aimed to evaluate the protective effects of Centella asiatica, Daucus carota, and Brassica oleracea extracts against dexamethasone-induced muscle atrophy. In vivo experiments were conducted using a dexamethasone-induced muscle injury model in mice. Following induction of muscle atrophy, plant extracts were administered for two weeks. Muscle strength was assessed using a grip strength meter, and histological analysis was performed on the gastrocnemius tissues. All three extracts significantly restored grip strength and preserved muscle fiber size. At the molecular level, the extracts suppressed FoxO3a-mediated expression of the atrophy-related genes MuRF1 and MAFbx, while enhancing phosphorylation of Akt and mTOR. Myogenic markers MyoD and Myogenin were also upregulated. Furthermore, similar protective effects were observed in dexamethasone-treated C2C12 myotubes, including recovery of myotube diameter. Mechanistically, the extracts inhibited catabolic signaling through downregulation of FoxO3a and promoted myogenesis via activation of the Akt/mTOR pathway. These findings support the potential therapeutic application of C. asiatica, D. carota, and B. oleracea extracts for the prevention and treatment of muscle atrophy.