氯化汞会导致严重的肝损伤,涉及多种机制。Ferroptosis在肝脏病理的发生发展中起着重要的调节作用。齐墩果酸(OA),三萜类化合物广泛存在于水果中,具有肝脏保护特性。在这项研究中,我们研究了铁凋亡在氯化汞诱导的肝损伤中的作用以及OA的干预作用,并阐明了潜在的机制。我们发现氯化汞诱导肝脏组织和细胞的氧化应激,导致脂质过氧化和铁过载,从而降低GPX4和SLC7A11的表达水平,增加TRF1的表达水平,OA预处理改善了氯化汞诱导的GPX4、SLC7A11和TRF1的变化,这与其抑制氧化应激有关。此外,我们用OA预处理细胞,VC,和Fer-1,分别发现VC预处理降低了氯化汞暴露细胞的氧化应激并显着逆转了GPX4,SLC7A11和TRF1的基因和蛋白表达(P<0.05,vs.HgCl2基团),然而,OA治疗组GPX4蛋白表达水平低于VC治疗组(P<0.05)。Fer-1预处理降低了细胞中铁离子的水平,GPX4和SLC7A11基因和蛋白表达水平升高,TRF1基因和蛋白表达水平降低(P<0.05,HgCl2基团),然而,OA预处理组GPX4和SLC7A11蛋白表达水平低于Fer-1预处理组(P<0.05)。此外,体内实验还表明,用OA预处理,VC,和Fer-1逆转了氯化汞诱导的Nrf2和SOD1基因表达水平以及GPX4蛋白表达的变化(P<0.05,HgCl2基团),同时,OA间差异无统计学意义,VC,和Fer-1预处理。OA预处理对氯化汞引起的TFR1蛋白表达变化的改善作用与Fer-1和VC相似,然而,OA对SLC7A11蛋白表达的干预效果不如Fer-1和VC预处理。总而言之,所有这些结果表明铁死亡与氯化汞诱导的肝损伤有关,OA预处理通过抑制ROS产生和铁离子过载减轻氯化汞诱导的铁凋亡,然后减轻肝脏损伤。
Mercury chloride can cause severe liver injury, which involves multiple mechanisms. Ferroptosis plays an important role in regulating the development and progression of liver pathology. Oleanolic acid (OA), a triterpenoid compound widely exists in fruits, has liver protective properties. In this study, we investigated the role of ferroptosis in mercury chloride-induced liver injury and the intervention effect of OA, and clarified the potential mechanism. We found that mercury chloride-induced oxidative stress in liver tissues and cells, leading to lipid peroxidation and iron overload, thereby reducing the expression levels of GPX4 and SLC7A11, and increasing the expression level of TRF1, OA pretreatment improved the changes of GPX4, SLC7A11 and TRF1 induced by mercury chloride, which were related to its inhibition of oxidative stress. Furthermore, We pretreated cells with OA, VC, and Fer-1, respectively and found that VC pretreatment reduced oxidative stress and significantly reversed the gene and protein expressions of GPX4, SLC7A11, and TRF1 in mercury chloride-exposed cells (P < 0.05, vs. HgCl2 group), however, the protein expression level of GPX4 in OA pre-treatment group was lower than that in VC pre-treatment group (P < 0.05). Fer-1 pretreatment decreased the level of iron ions in cells, increased the gene and protein expression levels of GPX4 and SLC7A11, and decreased the gene and protein expression levels of TRF1 (P < 0.05, vs. HgCl2 group), however, the protein expression levels of GPX4 and SLC7A11 in OA pre-treatment group were lower than those in Fer-1 pre-treatment group (P < 0.05). Moreover, vivo experiments also demonstrated that pre-treatment with OA, VC, and Fer-1 reversed the changes in gene expression levels of Nrf2 and SOD1, and protein expression of GPX4 induced by mercury chloride (P < 0.05, vs. HgCl2 group), meanwhile, the difference was not statistically significant among OA, VC, and Fer-1 pretreatment. The improvement effect of OA pretreatment on the change in TFR1 protein expression caused by mercury chloride was similar to that of Fer-1 and VC, however, the intervention effect of OA on SLC7A11 protein expression was not as good as Fer-1 and VC pre-treatment. To sum up, all these results suggest that ferroptosis is involved in mercury chloride-induced liver injury, OA pretreatment alleviated mercury chloride-induced ferroptosis by inhibiting ROS production and iron ion overload, and then alleviate the liver injury.