Ejiao alleviates sarcopenia by AKT/mTOR/Foxo3a and AMPK pathways in an aging rat model induced by D-Galactose combined with restricted movement.

Abstract

ETHNOPHARMACOLOGICAL RELEVANCE: Ejiao (Asini Corii Colla, donkey-hide gelatin from the hide of Equus asinus Linnaeus., ACC) is a traditional Chinese medicine (TCM) which has a long history and wide application in "nourishing Qi and nourishing blood". AIM OF THE STUDY: To investigate the effects and underlying mechanisms of Ejiao in the treatment of sarcopenia. MATERIALS AND METHODS: In this study, we firstly established a sarcopenia rat model through 14-week regimen of subcutaneous D-galactose (D-gal) injection combined with restricted movement. Subsequently, we observed the basic growth and muscles of the sarcopenia rats, the locomotor activities were also tested. Muscle histopathology, oxidative stress biochemicals and ATP content in the gastrocnemius muscle were examined. Then, the proteomics combined with metabolomics strategy was applied to predict possible pathways. Finally, quantitative real-time polymerase chain reaction (qRT-PCR) and Western blot analyses were carried out to validate the mechanisms of effects of Ejiao on sarcopenia. RESULTS: Following Ejiao administration, we observed significant increases in body weight and gastrocnemius muscle mass, alongside improvements in locomotor activities, muscle morphology and pathology. Further research demonstrated that Ejiao not only effectively reduce oxidative stress in the sarcopenic rats, evidenced by decreased superoxide dismutase activity and tissue levels of lipid peroxide malonaldehyde, while but also enhance ATP levels in the muscles. Our integrative analysis of proteomics and untargeted metabolomics revealed that Ejiao's benefits are mainly mediated through modulation of AKT/mTOR/Foxo3a signaling pathway and the AMPK pathway, both crucial for protein synthesis and muscle function enhancement. Further qRT-PCR and Western blot analyses confirmed the effects of Ejiao on these pathways. CONCLUSIONS: These findings suggest that Ejiao significantly improves muscle function and provides a promising avenue for sarcopenia treatment, highlighting its potential as a novel therapeutic candidate.