Oxymatrine Inhibits Homocysteine-Mediated Autophagy via MIF/mTOR Signaling in Human Umbilical Vein Endothelial Cells

Cellular Physiology and Biochemistry

Yanyan Zhang¹ 

关键词: Oxymatrine;    Homocysteine;    Autophagy;    Apoptosis;    HUVECs;   

DOI  :  10.1159/000487912

学科分类：分子生物学，细胞生物学和基因

来源: S Karger AG

【 摘 要 】

Background/Aims Genetic or nutritional deficiencies in homocysteine (Hcy)metabolism lead to the accumulation of Hcy and its metabolites in the blood. This can lead to hyperhomocysteinemia (HHcy), which is an independent risk factor for cardiovascular disease. Studies have shown that HHcy leads to endothelial dysfunction, a hallmark of atherosclerosis, which may explain this link. The precise mechanism remains unclear, but a strong possibility is excessive HHCy-induced autophagy. Autophagy has been better studied in ischemia/reperfusion (I/R) injuries, and previous work showed that Oxymatrine (OMT), a quinolizidine alkaloid, protects cells against myocardial I/R injury by inhibiting autophagy. The aim of this study was to determine whether OMT inhibits autophagy in HHcy. Methods Autophagy in HUVEC cells treated with Hcy in the presence and absence of OMT was visualized bytransmission electron microscopy and the degree was determined by western blotting and qRT-PCR. Small interfering RNA (siRNA)was used to determine the efficiency of Macrophage migration inhibitory factor (MIF) inhibition. Cell apoptosis wasdetected by western blotting and flow cytometric analysis. Results OMT inhibited autophagy, MIF, and mTOR in HUVECs during Hcy exposure, depending on the dose. siRNA-mediated MIF knockdown decreased Hcy-induced autophagy, while administration of 3-methyladenosine and rapamycin showed that they also induce autophagy. Furthermore, OMT dose-dependently inhibited the Hcy-induced HUVEC apoptosis/death. Conclusions These results suggest that Hcy can evokeautophagy-activated HUVEC apoptosis/death via a MIF/mTOR signaling pathway, which can be reversed by OMT. Our results provide a new insight into a functional role of OMT in the prevention of Hcy-induced HUVEC injury and death.

【 授权许可】

CC BY-NC-ND