Ineterventional Effect Of Activating Blood Circulation And Removing Stasis Herbs On Angiogensis In Atherosclerotic Plaque And Plaque Stability

Unstable plaque rupture of atherosclerosis(AS) is one of the main reasons of acute thrombus events.Therefore,how to stabilize plaque,prevent plaque rupture, intervene the occurrence and development of AS,and reverse AS plaque have important realistic meanings.Recent studies discovered that the pathological neovascularization frequently occurred in AS plaque which might facilitate the development of AS lesion,even induce the occurrence of hemorrhage in plaque and plaque rupture,as well as the incidence of complications.Therefore,inhibiting angiogenesis in plaque maybe play a potential role in enhancing plaque stability,preventing and treating acute coronary syndrome.Modern pharmacological studies demonstrated that the effects of Chinese drugs for activating blood circulation and removing stasis(ABCRS) in anti-atherosclerosis and promoting angiogenesis has been confirmed,moreover,whether ABCRS affect the stability of plaque and promote angiogenesis at same time has been an important problem should be concerned in clinical application of ABCRS in myocardial ischemia.Xiongshao Capsule(XSC),a Chinese herbal preparation formulated from the classic recipe for ABCRS,Xuefu Zhuyu Decoction,through extensive simplifying and refining,contains the active components from Red Paeonia and Rhizoma chuanxiong,namely Paeoniflorins and Chuanxiongols.Our previous experimental study showed that the two components have AS plaque stabilizing action,but whether they could impact the angiogenesis in AS plaque is still need to be probed further.This study is designed for exploring the relationship between plaque angiogenesis and plaque stability by means of the AS model induced by high fat diet and balloon angioplasty,and observing the effect of XSC from view points of AS plaque and angiogenesis in plaque for provideing experimental basis of its clinical application. This study is divided into two parts:literature review and experimental study.1.Literature Review:Progress in Vulnerable plaque and angiogenesis in plaque of AS were reviewed in this part.2.Experimental Study:Effect of Xiongshao Capsule on angiogensis in atherosclerotic plaque and plaque stability in rabbits was performed.Objective To investigate the relationship between angiogenesis in atherosclerotic plaque and plaque stability,and to observe the effect of XSC and mechanisms on angiogenesis and stability in atherosclerotic plaque in rabbits model.Methods Fifty New Zealand rabbits were randomized into the normal group,the model group,the Simvastatin group,the low-dose XSC group and the high-dose XSC group,10 in each group.Rabbits in the normal control group were fed with normal diet,while rabbits in the other four groups were fed with high fat diet and performed balloon angioplasty two weeks later to measure blood lipid and established abdominal aortic atherosclerosis models,then they were continued to be fed with high fat diet. Rabbits in the Simvastatin group,low-dose XSC group and high-dose XSC group were given Simvastatin 2.5mg/kg,XSC 0.24g/kg and 0.48g/kg per day,respectively. After 6-week successive medication,blood sampling from each group were prepared, the level of blood lipid was measured,the serum level of high sensitivite C-reactive protein(hsCRP),tumor necrosis factorα(TNF-α),matrix metalloproteinase-3,-9 (MMP-3,-9) and tissue inhibitor of metalloproteinase-1(TIMP-1) was detected with enzyme-linked immunoassay.After hematoxylin and eosin(HE) staining of abdominal aorta specimens,the gross pathomorphology indexes of plaque were observed under light microscopy,and the plaque area(PA),cross-sectional vascular area(CVA) and correcting plaque area(PA/CVA)were determined quantificationally by using imaging software;the protein expression of vascular endothelial growth factor(VEGF),factorⅧrelated antigen(FⅧRAg),MMP-3 and cluster of differentiation antigen 40 ligand (CD40L) in plaque was detected with immunohistochemical method.Linear correlation analysis was used to analyze the correlation of changes of the parameters. Results①In the model group,the obvious formation of lipid plaques in the abdominal aorta intima,and the diffuse distribution of lipid plaque formation could be seen even in the whole strip of some entire aorta intima.Although the formation of lipid plaque could be seen in the Simvastatin group,high- and low-dose XSC group abdominal aorta,it was still milder than the model group.HE staning showed that the obvious atherosclerotic plaque,intima was obvious thickening,a large number of foam cells in abdominal aorta intima,and cholesterol crystal and fibrous cap in plaque or under endothelial.The endothelial cell swelling,degeneration,the numbers of foam cells and lipid storage in all the drug intervention group was decreased than that in the model group.②The content of total cholesterol(TC),triglyceride(TG) and low-density lipoprotein cholesterol(LDL) was significantly increased before drug intervention than that in the normal group,respectively(P＜0.01),but it was insignificantly different among the four groups(P＞0.05).After drug intervention for 6 weeks,the content of TC was increased in a different degree in the Simvastatin group,high- and low-dose XSC group than the normal group(P＜0.01),and it was decreased than that in the model group(P＜0.05,P＜0.01).In addition,the serum levels of TG and LDL were significantly declined in the Simvastatin group.③The serum level of hsCRP in the model group was significantly higher than that in the normal group,and it was significantly lower in the Simvastatin group,high- and low-dose XSC group than that in the model group(P＜0.05,P＜0.01).④Compared with the model group,the serum levels of MMP-3,MMP-9 in the Simvastatin group,high- and low-dose XSC were significantly reduced than that in the model group(P＜0.05),while the expression of abdominal aortic MMP-3 and CD40L decreased significantly as well(P＜0.05,P＜0.01).⑤Histopathological morphologic changes showed that the difference of PA and CVA was insignificant among all the groups(P＞0.05),but the ratio of PA to CVA and PC in the Simvastatin group,high- and low-dose XSC group was significantly reduced than that in the model group(P＜0.05,P＜0.01).The MPT was significantly decreased in high- dose XSC group than that in the model group(P＜0.01).⑥After drug intervention 6 weeks,the level of VEGF and FⅧRAg in high- and lowdose XSC group and Simvastatin group was significantly reduced than that in the model group,respectively(P＜0.05,P＜0.01).⑦Linear correlation analysis demonstrated there was a positive correlation between VEGF and PA/CAV(r=0.770,P＜0.01);and MMP-3 is closely related to CD40L(r=0.887,P＜0.01).Conclusion Plaque stabilization is closely related to plaque angiogenesis. Xiongshao Capsule and Simvastatin may play an important role in stabilizing AS plaque,its mechanism not only relevant to regulate lipid metabolism,regress inflammation and suppress matrix metalloproteinase,but also inhibit plaque angiogenesis.