Abstract：
Sodium aescinate (SA), an active compound found in horse chestnut seeds, is widely used in clinical practice. Recently, the incidence of SA-induced adverse events, particularly renal impairment, has increased. Our previous work demonstrated that SA causes severe nephrotoxicity via nephrocyte ferroptosis; however, the underlying mechanism remains to be fully elucidated. In the current study, we investigated additional molecular pathways involved in SA-induced nephrotoxicity. Our results showed that SA inhibited cell viability, disrupted cellular membrane integrity, and enhanced reactive oxygen species (ROS), ferrous iron (Fe2+), and malondialdehyde (MDA) levels, as well as lipid peroxidation in rat proximal renal tubular epithelial cell line (NRK-52E) cells. SA also depleted coenzyme Q10 (CoQ10, ubiquinone) and nicotinamide adenine dinucleotide (NADH) and reduced ferroptosis suppressor protein 1 (FSP1) and polyprenyltransferase (coenzyme Q2, COQ2) activity, triggering lipid peroxidation and ROS accumulation in mouse kidneys and NRK-52E cells. The overexpression of COQ2, FSP1, or CoQ10 (ubiquinone) supplementation effectively attenuated SA-induced ferroptosis, whereas iFSP1 or 4-formylbenzoic acid (4-CBA) pretreatment exacerbated SA-induced nephrotoxicity. Additionally, SA decreased nuclear factor-erythroid-2-related factor 2 (Nrf2) levels and inhibited Nrf2 binding to the -1170/-1180 bp ARE site in FSP1 promoter, resulting in FSP1 suppression. Overexpression of Nrf2 or its agonist dimethyl fumarate (DMF) promoted FSP1 expression, thereby improving cellular antioxidant capacity and alleviating SA-induced ferroptosis. These results suggest that SA-triggers renal injury through oxidative stress and ferroptosis, driven by the suppression of the Nrf2/FSP1/CoQ10 axis.
摘要：
七叶皂苷钠(SA),在马栗种子中发现的一种活性化合物，广泛应用于临床。最近,SA引起的不良事件的发生率，特别是肾功能损害，增加了。我们以前的工作表明，SA通过肾细胞铁性凋亡引起严重的肾毒性；然而，潜在的机制仍有待充分阐明。在目前的研究中,我们研究了与SA诱导的肾毒性有关的其他分子途径.我们的结果表明，SA抑制细胞活力，破坏细胞膜的完整性，和增强的活性氧（ROS），亚铁（Fe2+），丙二醛（MDA）水平，以及大鼠近端肾小管上皮细胞系（NRK-52E）细胞的脂质过氧化。SA还耗尽了辅酶Q10（CoQ10，泛醌）和烟酰胺腺嘌呤二核苷酸（NADH）以及降低的铁凋亡抑制蛋白1（FSP1）和聚异戊二烯基转移酶（辅酶Q2，COQ2）活性，在小鼠肾脏和NRK-52E细胞中触发脂质过氧化和ROS积累。补充COQ2，FSP1或CoQ10（泛醌）的过表达有效地减弱了SA诱导的铁细胞凋亡，而iFSP1或4-甲酰苯甲酸（4-CBA）预处理会加剧SA诱导的肾毒性。此外,SA降低了核因子-红系-2相关因子2（Nrf2）水平，并抑制了Nrf2与FSP1启动子中-1170/-1180bpARE位点的结合，导致FSP1抑制。过表达Nrf2或其激动剂富马酸二甲酯（DMF）促进FSP1表达，从而提高细胞抗氧化能力并减轻SA诱导的铁凋亡。这些结果表明，SA通过氧化应激和铁凋亡引发肾损伤，由Nrf2/FSP1/CoQ10轴的抑制驱动。
