Soluble Dipep-tidyl Peptidase 4 Induce Human Aortic Smooth Muscle Cells Calcification Through Generation Of Reactive Oxygen Species And Activation Of ERK1/2-NF-?B Signaling Pathway

Objective:The aim of the research was to investigate the effect and mechanism of soluble Dipep-tidyl peptidase 4?sDPP4?on the calcification of HASMCs.Methods:In this study,we investigated the effects of DPP-4 on calcification in human vascular smooth muscle cells?HVSMC?by Alizarin red staining.Von kossa staining method was applied to test the effect of sDPP4 on calcification of HASMCs,and 2',7'-Dichlorofluorescin diacetate?DCFDA?method was usesd to detect the production of reactive oxygen species?ROS?;Four signaling pathways inhibitors were added to verify the mechanism of sDPP4-induced calcification of HASMCs.Subsequently,We further examined the activation ERK1/2 pathway of DPP-4,then used an inhibitor of ERK1/2 pathway,PD98059 inhibited DPP4-induced calcification production,such as OPG,OPN,BMP-2 and RUNX2 in HVSMC.Results:The Alizarin red staining results are shown,Compared with the control group,DPP4 group calcified nodules increased significantly,same as calcification group?And Western blot results are shown the expression of OPG,OPN,RUNX2,BMP2protein in DPP4 group was in a concentration-dependent and time-dependent manner.The expression of P-ERK1/2 was significantly increased at 15Min and500ng/ml DPP4.Compared with the DPP4 group,the expression of of OPG,OPN,RUNX2,BMP2 in the inhibitor group was significantly lower.The calcified nodules in s DPP4 group increased significantly compared to that in control group,while the expression of OPG?38.41%,18.41%?,OPN?41.81%,61.58%?,RUNX2?44.21%,59.4%?,BMP2?48.3%,52.19%?in sDPP4+PD98059 group and sDPP4+BAY11-7082 group was significantly decreased.The expression of p-ERK1/2 increased at 15 minutes under 500ng/ml sDPP4,and the expression of p-NF-?Bsubsequently increased at 60minutes under 500 ng/ml sDPP4.However,the expression of p-NF-?B decreased significantly in sDPP4+ERK1/2group.The expression of P-ERK1/2 and P-NF-KB reduced in N-acetylcysteine group,while the expression of P-ERK1/2 and P-ERK1/2 increased in H₂O₂ group.Conclusion DPP 4 advances the calcification of human VSMC,the possible mechanism is activate the ERK1/2 signaling pathway.sDPP4 might promote the calcification of HASMCs via the ERK1/2-NF-?B signaling pathway.