Aloperine-induced Autophagy Reduces Vascular Restenosis After Balloon Injury

Background:Vascular restenosis is the pathological basis of many cardiovascular diseases including restenosis after angioplasty,and the proliferation and migration of vascular smooth muscle cells(Vascular smooth muscle cells,VSMCs)play a key pathophysiological role in cardiovascular diseases such as restenosis.Vascular smooth muscle cells are the main cellular components of vascular wall structure,and the abnormal proliferation of vascular smooth muscle cells is considered to be the pathological basis of cardiovascular diseases such as vascular restenosis.Under the stimulation of certain factors,vascular smooth muscle cells can exhibit abnormal proliferation,showing similar biological behavior to tumor cells,and many signal transduction pathways of them are consistent.Therefore,the use of antitumor drugs in the treatment of vascular hyperplasia may be a new therapeutic strategy is being extensively studied.And aloperine,derived from Sophora alopecuroids L.,has antibacterial,anti-inflammatory,anti-allergic,anti-tumor,anti-oxidative and other pharmacological effects,and has protective effects on renal,neuronal,pulmonary vascular remodeling,indicating that aloperine may be a potential drug to prevent and treat cardiovascular disease.Objective:Abnormal proliferation and migration of vascular smooth muscle cells play a key role in the pathophysiological process of vascular restenosis.Whereas,aloperine has recently been shown to inhibit the proliferation of pulmonary vascular smooth muscle cells,thus inhibiting pulmonary vascular remodeling,thereby improving pulmonary hypertension.However,the effect and mechanism of aloperine on the proliferation and migration of vascular smooth muscle cells after balloon injury are not clear.Therefore,there is a strong interest in studying the effects of aloperine on the proliferation and migration of vascular smooth muscle cells after balloon injury,and it is necessary to clarify the role and mechanism.Methods:In this study,hematoxylin/eosin(HE)staining and immunohistochemical staining were used to determine the rat carotid artery proliferation and contractile phenotype.CCK8 and EdU staining were used to determine the proliferation level of vascular smooth muscle cells.Western blot was used to determine the expression of autophagy,proliferation and contraction phenotype-related proteins.Electron microscopy and confocal microscopy were used to locate autophagosomes,and scratch experiment was used to assess the ability of aloperine to migrate to vascular smooth muscle cells stimulated by platelet-derived growth factor(PGDF-BB).Moreover,specific autophagy inhibitor was used to evaluate the effects of aloperine on autophagy.Results:In animal experiments,the carotid wall area of the BI+ALO group was significantly lower than that of the BI group(P<0.05),indicating that treatment with aloperine after balloon injury could reduce vascular intimal hyperplasia.Compared with the BI group,the expression of PCNA protein in the BI+ALO group decreased(P<0.01),proving that aloperine can inhibit the proliferation of blood vessels after balloon injury,the expression of SM22a protein increased significantly(P<0.01),confirming that aloperine can inhibit the phenotype conversion of vascular smooth muscle cells,and the expression of LC3-? protein increased significantly(P<0.05),indicating that aloperine can upregulate the autophagy of vascular smooth muscle cells.In cell experiments,compared with the PDGF group,the EdU results of the PDGF+ALO group showed that aloperine could inhibit the proliferation of vascular smooth muscle cells(P<0.01),the expression level of PCNA decreased(P<0.05),further verifying that aloperine inhibited the proliferation of vascular smooth muscle cells,the expression of LC3-II protein increased(P<0.01),and the expression of p62 protein also increased significantly(P<0.05),further confirming that aloperine can upregulate the autophagy of vascular smooth muscle cells,the percentage of migration area was significantly reduced(P<0.05),confirming that aloperine can inhibit the migration of vascular smooth muscle cells.After adding 3-MA co-treatment,it can reverse the effect of aloperine on inhibiting the proliferation and migration of vascular smooth muscle cells and the effect of inducing autophagyConclusion:Our results show that aloperine can improve vascular restenosis after balloon injury,and inhibit the proliferation and migration of vascular smooth muscle cells stimulated by PDGF-BB by inducing autophagy.