Effect On Outcomes And Plaque Autophagic Flux With The Different Courses Of Statins Treatment Before Carotid Endarterectomy

Part I observational study on statins pre-reatment beforecarotid endarterectomy on outcomes patients with moderateto severe atherosclerotic carotid stenosisObjective To oberve the effect on outcomes of patients with moderate to severe atherosclerotic carotid stenosis with long-term statins pre-treatment or peri-operative statins treatment before carotid endarterectomy(CEA).Methods Collecting the clinical data about patients with symptomatic carotid stenosis(NASCET﹥50%) or asymptomatic carotid stenosis(NASCET﹥70%) who received CEA in the first affiliated hospital of Soochow University, according to the time of statins pre-treatment, which of these patients were divided into two groups: long-term statins treatment(﹥3 months) and pre-operative statins treatment(﹤7days). The clinical characters of baseline, the degree of stenosis of these two groups were observed as admitted to hospital, the status of restenosis, death and stroke reoccurrence were observed parallelly.Results There were 31 CEA cases recuited, including 28 male cases, and the average age was 70±7.86. There were 15 cases in long-term statins group, another 16 cases in peri-operative statins group. Both groups did not differ each other in age, gender, history of basal diseases, history of smoking and drinking, while the level of low density lipoprotein-cholesterol(LDL-C) in long-term statins group was lower significantly than in peri-operative statins group with statistics meaning(P﹤0.05). There were 10 cases of symptomatic patients(66.7%) and 5 cases of asymptomatic patients(33.3%) in long-term statins group; while 13 cases of symptomatic patients and 3 cases of asymptomatic patients in peri-operative statins group. The average degree of stenosis in long-term statins group and peri-operative statins group were 0.856±0.109 and 0.836±0.119, respectively. Both groups did not differ each other in symptoms, location and degree of stenosis. As to outcomes, the time spanned between 5-26 months(the median was 8 in long-term group, and 18 in peri-operative group). Two cases in peri-operative statins group were lost during follow-up, another two were death and restenosis, respectively; there was no death and restenosis in long-term statins group. Both groups had no stroke reoccurrence. Therefore, outcomes were no significiant difference between two groups.Conclusions The level of LDL-C in long-term statins group was decreased compared to peri-operative statins group, there were no significant difference on outcomes such as death and restenosis between these two groups.Part Ⅱ The effect of long-term statins pre-treatment or peri-operative statins treatment on the organizationalstructure and autophagic flux of plaqueObjetive To observe the effect of long-term statins pre-treatment or statins pre-operative treatment on organizational structure and autophagic flux of plaques.Methods There were twenty-one atherosclerostic plaque samples obtained from CEA patients above-mentioned, including nine of peri-operative statins treatment plaques and twelve of long-term statins treatment plaques. Histologically, we observed the plaques stability of these two groups by hematoxylin and eosin(H-E) stainting; the ultrastructure of plaque cells were observed through transmission electron microscopy(TEM); the autophagic flux related proteins including microtubule-associated protein light chain(LC3)-II、P62、Cathepsin D of plaques between these two groups were analyzed through western blot methods. At last, the collocation and expression of autophagic flux related proteins on the macrophage, smooth muscle cells(SMCs) and endothelial cells were tested through the technology of immunofluorescence double-staining methods.Results Through H-E staining, plaques of peri-operative group have more cholesterol crystal, inflammatory cells infiltrating into subintimal and neovessels formation than long-term group. Though TEM, we found the formation of autophagosome in macrophagy of the peri-operative statins group was less than that of long-term statins group, while the excessive lipids content existed in cells of peri-operative statins group. The expression of autophagy related proteins were tested through western blot methods, the results showed that the proteins expression of LC3-II and Cathepsin D in long-term statins group was increased than the other group, while the expression of P62 was reduced in the former group. The results of immunofluorescence double-staining showed that the expression of proteins of MAP1-LC3, P62 and Cathepsin D collocated with landmark proteins of macrophage, SMCs and endothelial cells, in accordance with the results of western blot.Conclusions Long-term statins treatment contributes to the stability of plaque as well as the up-regulation of autophagic flux, which may be another probably mechanism of statins stabilizing plaques and need further confirmation through animals and cells tests.