鸢尾素改善载脂蛋白E基因敲除糖尿病小鼠动脉粥样硬化

Irisin Improving Atherosclerosis Condition in Apo E^(-/-) Diabetes Mellitus Mice

目的:探索鸢尾素(Irisin)对动脉粥样硬化的作用及其可能机制。方法:建立载脂蛋白E基因敲除(Apo E-/-)小鼠糖尿病模型(n=20)并分为鸢尾素组(n=10)、糖尿病对照组(n=10),同时设立空白对照组(n=10),分别静脉注射鸢尾素或等量生理盐水。鸢尾素干预4周后,测定血管内皮依赖性舒张功能。干预12周后,检测血清肿瘤坏死因子-α(TNF-α)、C-反应蛋白、白细胞介素-6(IL-6)及氧化低密度脂蛋白等炎性因子水平;油红O及苏木素伊红(HE)染色分析主动脉粥样斑块表面积及横断面积;抗CD68和抗CD90免疫组化染色测定斑块巨噬细胞及T淋巴细胞浸润;实时定量聚合酶链式反应(RT-PCR)分析主动脉壁IL-6、白细胞介素-10、TNF-α等炎性因子信使核糖核酸(m RNA)转录水平。结果:鸢尾素组与糖尿病对照组相比,小鼠内皮依赖性舒张功能改善,血中炎性因子水平降低,粥样斑块表面积[(22.57±2.17)%vs(35.09±2.38)%,P<0.05]及横断面积[(19.36±1.85)%vs(25.53±7.87)%,P<0.05]减小,斑块巨噬细胞[(30.5±2.79)%vs(41.34±9.13)%]、T淋巴细胞[(28.11±4.24)%vs(35.79±9.11)%]浸润减少,主动脉壁炎性因子m RNA转录水平下降[IL-6:1.76±0.50 vs 3.78±1.15;TNF-α:1.05±0.30 vs 2.11±0.48;细胞内黏附分子-1:1.96±0.69 vs 2.71±0.72;血管细胞黏附分子-1:0.87±0.21 vs 1.45±0.25;单核细胞趋化蛋白-1:1.34±0.34 vs 1.77±0.55],差异有统计学意义(P<0.05)。结论:鸢尾素可改善Apo E-/-糖尿病小鼠动脉粥样硬化,内皮保护及抗炎反应是其保护血管的重要机制。鸢尾素具有潜在的防治动脉粥样硬化的临床价值。

Objective：To explore the effect of irisin on atherosclerosis with possible mechanisms in diabetes mellitus（DM） mice.Methods：A total of 30 Apo E-/-mice were randomly divided into 2 groups：Control group,the mice received citrate buffer solution for modeling control,n=10.DM group,the mice received streptozotocin injection for DM modeling,n=20;the DM group was further divided into 2 subgroups as DM control（DM-C） group,the mice received normal saline injection for 12 weeks and DM ＋ irisin group,the diabetic mice received irisin injection for 12 weeks.n=10 in each subgroup.With 4 weeks of irisin intervention,the endothelium-dependent vasodilatation was detected.With 12 weeks of intervention,the blood levels of tumor necrosis factor-α（TNF-α）,high-sensitivity C-reactive protein（hs-CRP）,interleukin-6（IL-6） and oxidized low-density lipoprotein（ox-LDL） were examined by ELISA,the plaque areas in aortic en face and cross sections were measured by Oil red O or HE staining,the macrophages/T lymphocytes infiltration in plaques were detected with immunohistochemistry,and the m RNA expressions of IL-6,IL-10,TNF-α were determined by RT-PCR.Results：Compared with DM-C group,DM ＋ irisin group presented improved endothelium-dependent vasodilatation,decreased levels of blood inflammatory factors,reduced plaque on face area sections（22.57 ± 2.17） % vs（35.09 ± 2.38） % and cross sections（19.36 ± 1.85） % vs（25.53 ± 7.87） %,P 〈 0.05,less macrophages（30.5 ± 2.79） % vs（41.34 ± 9.13） % T andlymphocytes infiltration（28.11 ± 4.24） % vs（35.79 ± 9.11） % in plaques and lower m RNA expressions of inflammatory factors（IL-6：1.76 ± 0.50 vs 3.78 ± 1.15;TNF-α：1.05 ± 0.30 vs 2.11 ± 0.48;ICAM-1：1.96 ± 0.69 vs 2.71 ± 0.72;VCAM-1：0.87 ± 0.21 vs 1.45±0.25;MCP-1：1.34 ± 0.34 vs 1.77 ± 0.55） at aortic wall,P〈0.05.Conclusion：Irisin may improve atherosclerosis condition in Apo E-/-DM mice,the endothelial protection and antiinflammatory reaction were the important mechanisms.Irisin has the potential for preventing/treating atherosclerosis.