阿托伐他汀减轻巨噬细胞内质网应激及其介导的细胞凋亡

Atorvastatin alleviates endoplasmic reticulum stress and apoptosis in macrophages

目的探讨阿托伐他汀对7-酮胆固醇(7-KC)诱导的巨噬细胞内质网应激及细胞凋亡的影响。方法Aop E-/-小鼠左肾动脉和左颈总动脉联合部分结扎建立颈动脉易损斑块模型。采用HE染色方法观察斑块病理学改变,用免疫荧光结合激光扫描共聚焦显微镜技术检测斑块中内质网应激(ER stress)相关蛋白CHOP及磷酸化PERK(p-PERK)的表达。体外培养小鼠巨噬细胞RAW264.7,给予7-KC、H_2O_2或联合阿托伐他汀处理后,蛋白质免疫印迹方法(Western blot)测定ER stress相关蛋白CHOP、p-PERK、XBP-1s及凋亡相关蛋白cleaved caspase-3的表达。结果 Aop E-/-小鼠颈动脉易损斑块局部ER stress相关蛋白CHOP的表达及PERK磷酸化水平明显上调;7-KC可诱导小鼠巨噬细胞ER stress,进而诱导细胞凋亡;同时,氧化应激诱导剂H_2O_2也可通过诱导小鼠巨噬细胞ER stress介导细胞凋亡;而阿托伐他汀可抑制7-KC和H_2O_2诱导的巨噬细胞ER stress及其介导的细胞凋亡。结论ER stress可能参与AS易损斑块的形成;阿托伐他汀可通过减少细胞内氧化应激的水平,减轻巨噬细胞ER stress,从而抑制细胞凋亡。

AIM To investigate the effect of atorvastatin on 7-ketocholesteml reticulum stress （ER stress） and apoptosis in macrophages. METHODS （7-KC）-induced endoplasmic We generated an ApoE-/- mouse model of vulnerable carotid atherosclerotic plaque by partial ligation of the left common carotid artery and left renal artery. The pathological changes of atherosclerotic plaques were observed by hema- toxylin-eosin （HE） staining and the expression level or phosphorylation status of ER stress-associated proteins （CHOP and p-PERK） were detected by immunofluorescence staining. Macrophages （murine RAW 264.7 cells） were cultured and incubated with 7-KC or n202 with or without pretreatment with atorvastatin. ER stress-associated proteins （ CHOP, p-PERK, XBP-ls） and apoptotic protein （ cleaved caspase-3） were measured by Western blotting. RESULTS Vulnerable carotid atherosclerotic plaques from ApoE-/- mice showed induction of ER stress, as indicated by elevated CHOP levels and PERK phosphorylation. Levels of CHOP expression, PERK phosphorylation and cleavage of caspase-3 were elevated after exposure RAW264.7 cells to 7-KC, as well as to the direct inducer of oxidative stress H2O2. Atorvastatin inhibited 7-KC- and H2O2-induced ER stress and apoptosis in RAW264.7 cells in vitro. CONCLUSION 7-KC and oxidative stress induce ER stress and apoptosis in macrophages in vul- nerable atherosclerotic plaques. Atorvastatin inhibits ER stress and apoptosisvia reducing oxidative stress.