The Effect Of PKD2 On Activity Of ENOS By Ox-LDL In Vascular Endothelial Cells

Background:Atherosclerosis(AS) is a fatal disease in large and medium-sized arteries. And it is the main factor of myocardial infarction and cerebral infarction. It has been reported that the areas of AS occurring in are the bend and bifurcation in the arteries. It is well known that the hemodynamic factors play a critical role in regulating endothelial cells dysfunction and atherosclerosis formation. It has been reported that endothelial cells cilia plays a critical role in the process of hemodynamic signaling. PKD2 [polycystic kidney disease 2(autosomal dominant)] is mainly located in the cilia. And it plays a critical role in the biology behaviors of endothelial cells and the functions of vessel lumen. Previous studies illuminate that low oscillation shear stress(OS) can significantly inhibit the expression of PKD2 in endothelial cells. At the same time, Ox-LDL plays a critical role in regulating endothelial cells dysfunction and atherosclerosis formation. Therefore, does Ox-LDL regulate the expression and function of PKD2? This research studied endothelial cells and their PKD2 function, and tested for the effects of Ox-LDL on their PKD2 function.Objects:This research studied endothelial cells and their PKD2 function, and tested for the effects of Ox-LDL on their PKD2 function and the hypothesis that Ox-LDL down-regulates the activity of e NOS by the AMPK-e NOS signaling pathway that is regulated by PKD2, and plays a role in regulating endothelial cells dysfunction and atherosclerosis formation.Methods:The protein levels of PKD2 were observed by immunofluorescent staining assay(ICC assay), along with RT-PCR for the detection of PKD2 and Ca MKK? gene expression; Western blot technique was applied to detect protein levels including Ca MKK?, p-AMPK, AMPK, p-e NOS.Results:(1) Ox-LDL can inhibit the expression of gene and protein of PKD2 and the expression of protein of p-e NOS in endothelial cells.(2) PKD2 si RNA can result the gene silence of PKD2, and can inhibit the expression of gene and protein of PKD2 and the expression of protein of Ca MKK?, p-AMPK,p-e NOS in endothelial cells.(3) In vitro, Ox-LDL can inhibit the expression of gene of Ca MKK? and the expression of protein of p-AMPK in endothelial cells. And by using AICAR to treat endothelial cells, we demonstrated that Ox-LDL can inhibit the expression of protein of p-AMPK and p-e NOS in endothelial cells. In vivo, Apo E-/- mouse on high fat diet had raised levels of their weights and blood lipid, and inhibited the expression of gene of PKD2.Conclusion:(1) Ox-LDL can inhibit the expression of gene and protein of PKD2 and the activity of e NOS in endothelial cells.(2) Ox-LDL down-regulates the activity of e NOS by the AMPK-e NOS signaling pathway that is regulated by PKD2, and plays a role in regulating endothelial cells dysfunction and atherosclerosis formation.