Eleutheroside B alleviates LPS-induced lung injury in chicks by regulating autophagy via the AMPK/mTOR signaling pathway.

This study explored the protective effect and molecular mechanism of Eleutheroside B (EB) against lipopolysaccharide (LPS)-induced lung injury in chicks, along with its hepatic and renal biosafety. A total of 60 seven-day-old SPF chicks (n=10 per group) were assigned to control, EB single treatment, LPS model, low/high-dose EB intervention and AMPK inhibitor (Compound C) groups. LPS intratracheal instillation was used to establish the chick acute lung injury model. Pulmonary pathological changes, pulmonary edema, inflammatory cytokine expression, autophagy-related proteins and the AMPK/mTOR pathway activation were detected via HE staining, ELISA, RT-PCR, immunohistochemistry and Western blot. Network pharmacology and molecular docking were further applied for mechanism validation. Results showed EB markedly relieved LPS-triggered pulmonary edema, alveolar damage and inflammatory infiltration, and downregulated serum TNF-α and IL-1β levels. EB activated AMPK, inhibited mTOR, elevated Beclin-1 expression and LC3-II/LC3-I ratio, indicating enhanced autophagosome formation and activation of autophagic markers. Molecular docking confirmed EB could stably bind to AMPK and mTOR. Moreover, EB had no obvious hepatotoxicity and nephrotoxicity. In conclusion, EB alleviates LPS-induced chick lung injury by regulating the AMPK/mTOR-mediated autophagy and inflammation, with good biosafety, offering a new candidate agent for poultry pneumonia prevention and treatment.