Corchorus olitorius L. Protects Zebrafish Hair Cells Against Cisplatin-Induced Damage via Antioxidant and Anti-Apoptotic Mechanisms

Cisplatin is a widely used platinum-based chemotherapeutic agent that often causes irreversible hair cell loss, leading to hearing impairment. To date, effective strategies for preventing cisplatin-induced ototoxicity remain limited. Corchorus olitorius L. (COL) is rich in bioactive phytochemicals with antioxidant and anti-inflammatory properties; however, the protective role of COL stem against cisplatin-induced hearing loss has not been explored. This study aimed to determine whether COL stem extract treatment could mitigate cisplatin-induced hair cell damage in the lateral line system of zebrafish. Herein, we use 7-day post-fertilization (dpf) transgenic zebrafish larvae as a high-throughput screening platform to assessed COL stem extract against cisplatin-induced hair cell injury. Endpoints included mechanotransduction (MET) function, reactive oxygen species (ROS) production, apoptotic and inflammatory responses, and locomotor behavior. Antioxidant capacity and acute toxicity were also evaluated. Pretreatment with COL stem extract preserved hair cell viability, restored MET function, reduced ROS accumulation, upregulated Nrf-2-dependent cytoprotective genes, suppressed apoptosis, and attenuated macrophage infiltration. The recovery of swimming behavior correlated with hair cell protection, confirming the phenotypic relevance. This study demonstrates, for the first time, that COL stem exerts potent otoprotective effects through antioxidative, anti-apoptotic, and anti-inflammatory mechanisms, contributes to maintain mechanosensory function and swimming behavior. The findings support COL stem as a promising candidate for otoprotection and validate zebrafish-based high-throughput screening for novel therapeutic discovery.