Chiisanoside from the Leaves of Acanthopanax sessiliflorus Can Resist Cisplatin-Induced Ototoxicity by Maintaining Cytoskeletal Homeostasis and Inhibiting Ferroptosis

Ototoxicity is a common side effect of cisplatin cancer treatment, potentially leading to hearing loss. This study demonstrated the significant protective activity of Acanthopanax sessiliflorus (A. sessiliflorus) leaves against cisplatin-induced ototoxicity (CIO), investigated the active compounds, and elucidated their mechanisms in countering CIO. UPLC-Q/TOF-MS analysis identified 79 compounds. Network pharmacology and activity screening determined that chiisanoside (CSS) plays a crucial role in combating CIO. Transcriptomics combined with network pharmacology analysis and experiments revealed that CSS activates the Dock1/PIP5K1A pathway to suppress the actin-severing protein gelsolin, protecting hair cells from cisplatin-induced cytoskeleton damage. CSS also activates the SLC7A11/GPX4 pathway via TGFBR2, reducing lipid peroxidation and intracellular iron accumulation to suppress cisplatin-induced ferroptosis. This study discovers that the major component CSS in A. sessiliflorus leaves reverses CIO by regulating actin homeostasis via Dock1 and inhibiting ferroptosis through TGFBR2, providing a theoretical basis for expanding CIO treatment targets and related drug development.