Research On The Relationship Between Lp-PLA2, Annexin A1、Bax And Human Carotid Atherosclerotic Plaques

BackgroundThe third national sample survey on the cause of death, cerebrovascular disease has become the first cause of death in China. According to statistics, ischemic stroke accounts for75to80%of the cerebrovascular disease, and carotid atherosclerotic plaque rupture、ulcers and shedding are the important reasons of ischemic stroke. Therefore, carotid atherosclerotic plaque prevention is particularly important. Numerous studies find, the inflammation plays a key role in the development of atherosclerotic plaque occurrence、development、ulcers、plaque hemorrhage and rupture. Lipoprotein-associated phospholipase A2is a new type of inflammatory markers discovered in recent year, may participate in human carotid atherosclerotic plaque occurrence、development、rupture and thrombosis. Annexin A1is an important inflammatory regulatory protein, and play a very important role in the process of inflammatory metabolites、neutrophil/monocyte cells and endothelial cell adhesion. Bax is a pro-apoptotic gene, and affect cell apoptosis, may be related to the stability of the atherosclerotic plaque. Therefore, Lp-PLA2、Annexin A1、Bax may play an important role in the occurrence、development and stability of human carotid atherosclerotic plaque. At home and abroad,the research on the relationship between Lp-PLA2、Annexin A1、Bax and human carotid atherosclerotic plaques is rarely reported.ObjectiveIn this study,Lp-PLA2level was measured in carotid atherosclerotic plaque group and the healthy control group,and the expression Annexin A1and Bax was determined in human carotid atherosclerotic plaques and normal mesenteric artery,to investigate the correlation between the expressions of Annexin Al and Bax、the level of lipoprotein-associated phospholipase A2(Lp-PLA2) and the formation and stability of human carotid atherosclerotic plaques.Methods45cases of human carotid atherosclerotic plaques specimens (test group, group A) and20specimens of patients with mesenteric artery (control group, group B) were collected after operation. The carotid atherosclerotic plaques specimens were divided into soft plaque (group A1, n=15), mixed plaque (group A2, n=15), hard plaque (group A3, n=15) according to the result of carotid artery ultrasound.1.Lp-PLA2level was measured by enzyme linked immunosorbent assay(ELISA) in45cases of plaque (15cases of soft plaque,15cases of mixed plaque,15cases of morphea) and20cases of healthy control group.2. The mRNA expressions of Annexin A1and Bax were determined by RT-PCR in45cases of plaque (15cases of soft plaque,15cases of mixed plaque,15cases of morphea) and20cases of normal mesenteric artery.3. The protein expressions of Annexin A1and Bax were determined by Western blot in45cases of plaque (15cases of soft plaque,15cases of mixed plaque,15cases of morphea) and20cases of normal mesenteric artery.4. The SPSS18.0statistical software was used for statistical analysis. The level of Lp-PLA2, expression levels of Annexin Al and Bax mRNA and protein in the four groups,were analysed using One-way analysis of variance (ANOVA), The LSD test was used to compare the results between groups, the inspection level α= 0.05.Result1. The level of Lp-PLA2The level of Lp-PLA2was significantly increased in human carotid atherosclerotic plaques compared with healthy control tissues (P<0.05); group A1was significantly highter than group A3(P<0.05);2. The expressions of Annexin A1mRNA and protein The expressions of Annexin A1mRNA and protein were significantly increased in human carotid atherosclerotic plaques compared with control tissues (P<0.05); group A1exhibited lower mRNA and protein expression than group A3(P<0.05);3. The expressions of Bax mRNA and protein The expressions of Bax mRNA and protein were significantly increased in carotid atherosclerotic plaques compared with control tissues (P<0.05); group A1exhibited highter mRNA and protein expression than group A3(P<0.05).Conclusion1. Lp-PLA2、Annexin A1and Bax participate in the formation and stability of human carotid atherosclerotic plaques.2. Lp-PLA2and Bax promote the formation of atherosclerotic plaques of carotid and induce plaque instability.3. Annexin A1has a role in anti-atherosclerosis and plaque stabilization.