Sodium aescinate induces hepatotoxicity through apoptosis and ferroptosis by inhibiting the Nrf2/CTH pathway

The seed of Aesculus wilsonii Rehd., also known as Suoluozi in China, is a traditional Chinese herb included in the Pharmacopoeia of China (2020). Sodium aescinate (SA) is derived from the Aesculus wilsonii Rehd.'s seeds and is extensively used in clinical practice.

The study investigated the involvement of the Nrf2/CTH pathway in SA-induced hepatotoxicity and explored potential strategies for alleviating SA-induced liver damage.

The ICR mice and AML12 mouse hepatocytes were exposed to SA. The levels of Fe²⁺, cysteine (Cys), glutathione (GSH), hydrogen sulfide (H₂S), ROS, lipid peroxides and caspase-3 activity were assessed. The effects of SA on signaling pathways related to ferroptosis and apoptosis were examined. Furthermore, genetic modification or agonists of Nrf2 and CTH were co-treated with SA.

SA triggered ferroptosis and apoptosis in AML12 cells and mouse livers, characterized by a decline in Cys, GSH, and H₂S levels, as well as accumulation of Fe²⁺, ROS and lipid peroxides, mitochondrial dysfunction, and chromatin condensation. SA decreased Nrf2, CTH, and Bcl-2 levels, elevated Bax levels, and activated caspase-9/3. Overexpression of Nrf2 or CTH, or NAC supplementation alleviated SA-induced ferroptosis by upregulating Cys and GSH levels. Overexpression of Nrf2 or CTH, or NaHS supplementation increased H₂S levels, which reduced the interaction between p616-Drp1 and VDAC1 by enhancing Drp1 S-sulfenylation, thereby alleviating SA-induced mitochondrial-dependent apoptosis. Furthermore, DMF or Met mitigated SA-induced hepatotoxicity by activating the Nrf2/CTH pathway.

SA triggers oxidative stress, mitochondrial dysfunction, apoptosis, and ferroptosis, ultimately leading to liver damage by suppressing the Nrf2/CTH pathway.