N-acetylcysteine Attenuates The Toxicity Of Metal-organic Framework On Ea.hy926 Vascular Endothelial Cells

Objective:Metal-organic frameworks（MOFs）are kinds of crystalline porous materials composed of metal ions and organic ligands,which are characterized by easily synthesis and functionalization,adjustable aperture,variable structures,high surface area and so on.As a member of MOFs materials,zeolitic imidazolate frameworks（ZIFs）have been developed rapidly and attracted considerable attention for application in nano drug delivery system,which raised attention to cardiovascular disorders.Currently,the mechanism of cytotoxicity of ZIFs in cardiovascular disease is unknown.Our experiments investigated the toxicity of ZIF-8 to human EA.hy926 vascular endothelial cells,as well as the effect of the antioxidant N-acetylcysteine（NAC）on ZIF-8 treated EA.hy926 cells.Methods:Firstly,we used CCK-8 detection kit to determine the IC₂₀and IC₅₀ of ZIF-8 on EA.hy926 vascular endothelial cells,and then the experiments were carried out in five groups:Control,IC₂₀,IC₅₀,IC₂₀+NAC and IC₅₀+NAC.The cell viability,ROS formation,apoptosis level,inflammatory response level,wound healing ability and the expression level of atherosclerosis related indicators ox-LDL of EA.hy926 endothelial cells in five groups were analyzed to evaluate the cytotoxicity of ZIF-8 on EA.hy926 cells and the ability of NAC to attenuate the toxicity.Finally,since the Wnt/β-catenin pathway is involved in regulating the function of vascular endothelial cells,Western blot method was used to clarify the expression levels of Wnt/β-catenin pathway correlated factorsβ-catenin and LEF1 in ZIF-8 and/or NAC treated EA.hy926 cells.Results:The IC₂₀ and IC₅₀ of ZIF-8 on EA.hy926 vascular endothelial cells were 18.90and 20.81μg/m L,respectively.ZIF-8 induces ROS formation,apoptosis,LDH release,and vascular endothelial cell dysfunction in EA.hy926 cells in a dose dependent manner.However,the addition of NAC could significantly reduce the effect of oxidation level,cell membrane damage and endothelial barrier function on ZIF-8 treated EA.hy926 cells.In addition,ZIF-8increased the expression levels ofβ-catenin and LEF1 in the IC₅₀ group,while NAC could significantly inhibit the increase ofβ-catenin and LEF1 protein expressions induced by ZIF-8.The results of the study help improve our understanding about the mechanism of ZIF-8-induced endothelial cell injury,and NAC had therapeutic potential in preventing ZIF-8-associated endothelial dysfunction by Wnt/β-catenin pathway.