PIAS3缺失促进雌性ApoE基因敲除小鼠动脉粥样硬化发展

PIAS3 deficiency exacerbates the development of atherosclerosis in female ApoE knockout mice

摘要:

目的]探讨活化STAT3蛋白抑制因子(PIAS3)缺失是否促进雌性ApoE基因敲除小鼠动脉粥样硬化(As)的发生发展。 [方法]繁育ApoE－/－背景的PIAS3基因敲除小鼠(PIAS3－/－/ApoE－/－),并饲喂高脂高胆固醇饮食12周诱导As。以同窝PIAS3＋/＋/ApoE－/－小鼠作为对照。每周测量小鼠体重,每4周检测血脂水平(包括总胆固醇、甘油三酯、高密度脂蛋白胆固醇和非高密度脂蛋白胆固醇)。对小鼠主动脉树、主动脉根部冰冻切片进行油红O染色、HE染色、免疫组织化学染色和免疫荧光染色,以评估As斑块的面积、细胞成分及其稳定性。此外,通过免疫荧光染色分析斑块内雌激素受体α(ERα)的表达及其与血管平滑肌细胞(VSMC)共定位情况。 [结果]与PIAS3＋/＋/ApoE－/－小鼠相比,PIAS3－/－/ApoE－/－小鼠的体重、主要脏器(心脏、肝脏、脾脏、肾脏和附睾脂肪)的重量及血脂水平均无明显改变；然而,PIAS3缺失促进了雌性PIAS3－/－/ApoE－/－小鼠As的形成。与PIAS3＋/＋/ApoE－/－小鼠相比,PIAS3－/－/ApoE－/－小鼠As斑块内脂质蓄积含量增加(P＜0.05),VSMC含量减少(P＜0.05),斑块稳定性降低。除此之外,PIAS3－/－/ApoE－/－小鼠As斑块内ERα的表达明显下调(P＜0.05),且ERα与VSMC存在明显共定位。PIAS3－/－/ApoE－/－小鼠斑块内VSMC的减少可能导致ERα的表达降低,进而减弱雌激素抗As的作用。 [结论]PIAS3缺失促进雌性ApoE－/－小鼠As斑块形成,并且PIAS3可能通过调控斑块内ERα的表达来发挥作用。

Abstract:

Aim To investigate whether protein inhibitor of activated STAT3 (PIAS3) deficiency exacerbates the occurrence and development of atherosclerosis (As) in female ApoE knockout mice. Methods PIAS3 gene knockout mice with ApoE－/－ background (PIAS3－/－/ApoE－/－) and their littermate PIAS3＋/＋/ApoE－/－ mice were bred and fed with a high-fat/high-cholesterol diet for 12 weeks to induce As. Body weight (every week) and plasma lipid levels including total cholesterol, triglyceride, high density lipoprotein cholesterol and non-high density lipoprotein cholesterol (every 4 weeks) of the mice were measured. Oil red O staining, HE staining, immunohistochemistry staining and immunofluorescence staining were performed on mouse aortic tree and frozen sections of aortic root to evaluate the area, cellular composition and stability of As plaques. Moreover, the expression of estrogen receptor α (ERα) and its co-localization with vascular smooth muscle cells (VSMC) in plaques were determined by immunofluorescence staining. Results Compared with PIAS3＋/＋/ApoE－/－ mice, PIAS3－/－/ApoE－/－ mice showed no significant differences in body weight, major organ weight (heart, liver, spleen, kidney and epididymal fat) and plasma lipid levels; however, PIAS3 deficiency promoted the formation of As in female PIAS3－/－/ApoE－/－ mice. Compared with PIAS3＋/＋/ApoE－/－ mice, PIAS3－/－/ApoE －/－ mice showed an increased lipid accumulation and a decreased VSMC content in As plaques (P＜0.05), leading to a decrease in plaque stability. In addition, the expression of ERα in the As plaques of PIAS3－/－/ApoE－/－ mice was significantly downregulated (P＜0.05), and there was a obvious co-localization between ERα and VSMC. The reduction of VSMC content in PIAS3－/－/ApoE－/－ mouse plaques might lead to a decrease of ERα expression, thereby weakening the anti-As effect of estrogen. Conclusion PIAS3 deficiency exacerbates the formation of As plaques in female PIAS3－/－/ApoE－/－ mice, which might be due to the regulatory effect of PIAS3 on ERα expression in plaques.