Deubiquitinase USP14 Regulated The Formation Of Foam Cell By CD36 Pathways

?Background?Atherosclerosis is regarded as a chronic progressive inflammatory disease and is a basic pathophysiological process in coronary artery disease.The formation of foam cell plays a key role in the pathogenesis of atherosclerosis.Scavenger receptor class B3(CD36)?mediated oxidized low-density lipoprotein(ox-LDL)uptake is a significant factor in progression of the formation of foam cell.Our previous studies have demonstrated that Ubiquitin-specific protease 14(USP14)mediates progression of cardiac hypertrophy and lipopolysaccharide(LPS)?induced inflammation.However,the underlying mechanism of USP14 is unknown in atherosclerosis.In this study,we focus on USP14 mediates lipid uptake and foam cell formation by regulates CD36 expression.We hope find out a novel pathogenesis of atherosclerosis.?Methods?1.LC?MS/MS analysis and molecular simulations technology were used to investigate the relationship between USP14 and CD36.2.Different methods were used to block the function of USP14(IU1 inhibited the enzyme activity of USP14,siRNA interfered with the transcriptional expression of USP14)in RAW264.7 and THP-1 cell,then studied the role of USP14 in regulation of lipid transport receptor(CD36,SR-A,Lox-1,ABCA1,ABCG1,SR-B1).3.Base on ox-LDL?mediated foam cell model,different methods were used to block the function of USP14(IU1 inhibited the enzyme activity of USP14,siRNA interfered with the transcriptional expression of USP14),then studied the role of USP14 in regulation of ox-LDL?mediated CD36 expression.4.The co-IP was used to study the interaction between USP14 and CD36.5.Confocal laser scanning microscope and flow cytometry assay were used to study the Dil-oxLDL uptake ability of macrophages in the presence or absence of USP14 inhibition.6.The Oil red O technology was used to study that level of foam cell was induced by ox-LDL in the presence or absence of USP14 inhibition.7.Antibody-dependent blocking assay was used to block the CD36,then further study the mechanism of USP14 on ox-LDL uptake in the presence or absence of USP14 inhibition.?Results?1.USP14 and CD36 can combines with each other.2.USP14 regulates CD36 expression by inhibits its degradation.3.The ox-LDL-induced up?regulation of CD36 expression is suppressed by the inhibition of USP14.4.USP14 interacts with CD36 and stabilizes CD36 expression.5.Inhibition of USP14 decreases Dil?oxLDL uptake in macrophages.6.The formation of foam cell is reduced by the inhibition of USP14.7.USP14 regulates ox-LDL uptake of macrophages and formation of foam cell depends on CD36.?Conclusion?Inhibition of USP14 decreases the formation of foam cell by promoting CD36 degradation.