利拉鲁肽基于NF-κB/NLRP3通路介导的焦亡途径对小鼠动脉粥样硬化的干预作用研究

Effect of liraglutide on atherosclerotic mice and its relation with NF-κB/NLRP3 mediated pyrosis pathway

目的基于NF-κB/NOD样受体蛋白3(NLRP3)通路,探讨利拉鲁肽[胰高血糖素样肽-1(GLP-1)类似物]对动脉粥样硬化(AS)小鼠模型的干预作用。方法取12只6周龄雄性C57BL/6J正常小鼠作为普通饮食组(A组),将36只6周龄SPF级雄性ApoE-/-小鼠随机分成高脂饮食组(B组,12只)、高脂饮食+利拉鲁肽组(C组,12只)和高脂饮食+利拉鲁肽+GLP-1受体抑制剂exendin(9-39)组(D组,12只)。各组小鼠饲养至18周龄后,检测血清中IL-6、IL-1β、TNF-α、HDL-C、LDL-C、TG和TC水平;HE染色检测小鼠主动脉病理学变化,并分析内膜中层厚度(IMT)及主动脉AS面积与所取血管面积比值;Western blot法检测主动脉内膜中NLRP3、半胱天冬酶-1(Caspase-1)、凋亡相关斑点样蛋白(ASC)、磷酸化NF-κB p65(p-NF-κB p65)、NF-κB p65蛋白表达水平。结果与A组相比,B组和D组小鼠的主动脉呈血管壁增厚,管腔狭窄,有大量斑块、炎性细胞浸润及脂质沉淀等病变,血清IL-6、IL-1β、TNF-α、LDL-C、TG、TC水平,主动脉IMT,主动脉AS面积与所取血管面积比值,主动脉内膜NLRP3、Caspase-1、ASC、p-NF-κB p65/NF-κB p65蛋白表达水平显著升高(P<0.05),HDL-C水平显著降低(P<0.05);与B组相比,C组小鼠主动脉病变程度明显减轻,血清中IL-6、IL-1β、TNF-α、LDL-C、TG、TC水平、主动脉IMT、主动脉AS面积与所取血管面积比值、主动脉内膜NLRP3、Caspase-1、ASC、p-NF-κB p65/NF-κB p65蛋白表达水平均降低(均P<0.05),HDL-C水平升高(P<0.05);与C组相比,D组小鼠主动脉病变程度明显加重,血清IL-6、IL-1β、TNF-α、LDL-C、TG、TC水平,主动脉IMT、主动脉AS面积与所取血管面积比值、主动脉内膜NLRP3、Caspase-1、ASC、p-NF-κB p65/NF-κB p65蛋白表达水平均升高(均P<0.05),HDL-C水平降低(P<0.05)。结论利拉鲁肽可通过抑制NF-κB/NLRP3信号通路,减轻AS小鼠的炎症反应和细胞焦亡,改善主动脉病理学损伤。

Objective To explore the protective effects of liraglutide(GLP-1 analogue)on atherosclerotic(AS)mice and its relation with NF-κB/NLRP3 pathway.Methods Twelve 6-week-old male C57BL/6J mice were selected as normal diet group(group A).Tthirty-six 6-week-old SPF male ApoE-/-mice were randomly divided into high-fat diet group(group B,n=12),high-fat diet+liraglutide group(group C,n=12),and high-fat diet+liraglutide+GLP-1 receptor inhibitor exendin(9-39)group(group D,n=12).The mice in each group were fed to 18 weeks old,the contents of interleukin-6(IL-6),interleukin-1β(IL-1β)and tumor necrosis factor-α(TNF-α),high-density lipoprotein cholesterol(HDL-C),low-density lipoprotein cholesterol(LDL-C),triglyceride(TG)and total cholesterol(TC)in serum were detected.Hematoxylin eosin staining was used to examine the pathological changes of the aorta,and the intima-media thickness(IMT)level and the ratio of atherosclerotic area of aorta to vascular area were analyzed.The protein expression levels of NLRP3,caspase-1,ASC,p-NF-κB p65 and NF-κB p65 in aortic tunica intima were detected by Western blot.Results Compared with those in group A,the aorta of group B and group D showed thickening of vascular wall,stenosis of lumen,a large number of plaques,inflammatory cell infiltration and lipid deposition,the contents of IL-6,IL-1β,TNF-α,LDL-C,TG and TC in serum,aortic IMT level,ratio of atherosclerotic area of aorta to vascular area,expression levels of NLRP3,Caspase-1,ASC and p-NF-κB p65/NF-κB p65 in aortic intima were significantly higher(P<0.05),the content of HDL-C was significantly lower(P<0.05).Compared with those in group B,the degree of aortic lesion in group C was significantly reduced,the contents of IL-6,IL-1β,TNF-α,LDL-C,TG and TC in serum,aortic IMT level,ratio of atherosclerotic area of aorta to vascular area,expression levels of NLRP3,Caspase-1,ASC and p-NF-κB p65/NF-κB p65 in aortic intima were significantly lower(P<0.05),the content of HDL-C was significantly higher(P<0.05).Compared with those in group C,the degree of aortic lesion in group D was more severe,the contents of IL-6,IL-1β,TNF-α,LDL-C,TG and TC in serum,aortic IMT level,ratio of atherosclerotic area of aorta to vascular area,expression levels of NLRP3,Caspase-1,ASC and p-NF-κB p65/NF-κB p65 in aortic intima were significantly higher(P<0.05),the content of HDL-C was significantly lower(P<0.05).Conclusion Liraglutide can reduce inflammation and pyrosis in AS mice and improve aortic pathological damage by inhibiting NF-κB/NLRP3 signaling pathway.