The Role Of ADAM17 In Pulmonary Artery Smooth Muscle Cell Proliferation And Its Mechanism

Background and purpose Pulmonary arterial hypertension,PAH is a fatal disease characterized by progressive pulmonary circulation resistance increases and the pulmonary artery reconstruction,eventually leads to right heart failure and death.Abnormal proliferation and migration of pulmonary artery smooth muscle cells,PASMCs is the main mechanism of pulmonary artery reconstruction;What the hot spot and the difficulty of PAH research are how to inhibit abnormal PASMC proliferation,promote its apoptosis,so as to prevent and reverse pulmonary vascular remodeling.Platelet derived growth factor,PDGF is the important mechanism mediated the abnormal proliferation of PASMCs.A Disintergrin And Metalloproteinase 17,ADAM17,also known as tumor necrosis factor alpha invertase,has the regulation of cell interactions(such as cell adhesion And aggregation)And important cytokines,cell factor receptor and other targets of hydrolysis activation.Research has revealed ADAM17 shortness of pressure overload mediated vascular remodeling effect,but has yet to clarify its role in PASMC proliferation,pulmonary artery reconstruction.Research shows that the mechanism is through two main ADAM17 dependent effect: MAPK/ERK1/2 activation and enhance cell glycolysis,early research team also showed that PDGF can promote rat pulmonary artery smooth muscle cells in the activation of Akt/m TOR signaling pathways.But has yet to reveal ADAM17 in pulmonary artery smooth muscle cell proliferation,the role of pulmonary artery reconstruction.We hypothesized that ADAM17 may participate in PASMC proliferation induced by PDGF,promote pulmonary artery reconstruction.This study intends to clarify ADAM17 mediated with the role of the pulmonary artery smooth muscle cell proliferation induce by PDGF and its downstream mechanism is discussed in this paper.Methods Human pulmonary artery smooth muscle cells(1)as the research object,using the immune cells staining alpha to smooth muscle actin(alpha actin)for identification.(2)to measure the proliferation rate by CCK8 assay;with different concentrations(0,5,10,15 ng/m L)of PDGF in PASMCs different processing time(0,6,12,24 h),Using Western blot detection of proliferating cell nucleus antigen(PCNA)protein levels to evaluate cell proliferation.(3)using Western blot detection ADAM17,ADAM33 expression level and Aktand ERK1/2phosphorylation level.(4)using ADAM17 inhibitors TAPI-1 in the process of cell proliferation induced by PDGF and the influence of the Akt and ERK1/2 signaling pathway.Result:(1)hemorphological observation andimmunocytochemistry staining identification showed that: the cells cultured were PASMCs.(2)PASMCs proliferation rate,PCNA protein expression quantity increase with the increase of concentration of PDGF treatment(P< 0.05);PASMCs proliferation rate,PCNA protein expression quantity increases with the increase of PDGF processing time(P<0.05).(3)PDGF increased the expression of ADAM17 protein with increasing of PDGF concentration and peak at 15ng/ml(P < 0.001).ERK1/2 and Akt phosphorylation level peaked at 10 ng/ml;PDGF increased the expression of ADAM17 protein with increasing of PDGF treatment time and peak 24 hours(P < 0.05);ERK1/2 and Akt phosphorylation levels increase with the increase of PDGF processing time and peak at 6 hours(P< 0.05).No obvious change in ADAM33 expression level(P > 0.05).(4)Compared withcontrol group,ADAM17 inhibitors TAPI-1significantly lower levels of ERK1/2(P < 0.01)but not lower Akt phosphorylation level(P >0.05).Compared with PDGF groups,with ADAM17 inhibitors TAPI-1 pretreatment group significantly lower levels of cell proliferation(P < 0.01)and ERK1/2(P< 0.001),but the level of Akt phosphorylation no significant influence(P>0.05).Conclusions1.ADAM17 may play an important role in PDGF stimulating pulmonary vascular smooth muscle cell proliferation2.The mechanism may be associated with ERK1/2 signal pathway,No obvious relationship with Akt signaling pathways.