降脂益肝汤预处理脂肪间充质干细胞来源外泌体对MAFLD铁死亡的保护作用OA

Objective To investigate the effect of exosomes derived from human adipose-derived mesenchymal stem cells preconditioned with Jiangzhi Yigan Decoction(JZYGT-Exo)on ferroptosis in a metabolic dysfunction-associated fatty liver disease(MAFLD)cell model and the underlying mechanisms involved.Methods Human adipose-derived mesenchymal stem cells were treated with serum containing JZYGT to obtain JZYGT-Exo,which were characterized using transmission electron microscopy(TEM)and nanoparticle tracking.An in vitro MAFLD model was established by inducing human hepatoblastoma HepG2 cells with a mixture of oleic acid and palmitic acid.Model,JZYGT-Exo,JZYGT-Exo+Era group,and JZYGT-Exo+Fer-1 groups were created.Lipid metabolism was assessed by Oil Red O staining,and intracellular triglyceride(TG)and glucose levels were measured.The cell viability was detected by the CCK-8 method.Levels of superoxide dismutase(SOD),malondialdehyde(MDA),reactive oxygen species(ROS),catalase(CAT),and glutathione peroxidase(GSH-Px)were detected.Mitochondrial membrane potential and morphology were evaluated using JC-1 and Mito-Tracker probes,respectively.Mitochondrial ultrastructure was observed by TEM,and glutathione peroxidase 4(GPX4)and nuclear factor erythroid 2-related factor 2(Nrf2)protein expression were detected by Western blot analysis.Results JZYGT-Exo were isolated and identified,and were effectively taken up by MAFLD model cells.JZYGT-Exo intervention significantly reduced intracellular lipid deposition as well as TG and glucose levels(P＜0.01,P＜0.001).Cell death mode screening indicated that JZYGT-Exo antagonized Erastin-induced ferroptosis.JZYGT-Exo increased SOD,CAT,and GSH-Px activities(P＜0.05),decreased MDA and ROS levels(P＜0.05,P＜0.01),enhanced mitochondrial membrane potential(P＜0.05),improved mitochondrial morphology and ultrastructure,reduced mitochondrial iron deposition,and up-regulated GPX4 and Nrf2 protein expression(P＜0.01);these effects were partially reversed by Erastin and were enhanced by Fer-1.Conclusions JZYGT-Exo ameliorated lipid metabolism disorders and inhibited ferroptosis in MAFLD model cells by regulating key oxidative stress and ferroptosis proteins.Their mechanism of action may be related to Nrf2/GPX4 signaling activation.