冠心康对ApoE^(-/-)动脉粥样硬化小鼠PPARγ-LXRα-ABCA1信号通路的影响

Effects of Chinese herbal medicine Guanxinkang on expression of PPARγ- LXRα-ABCA1 pathway in ApoE-knockout mice with atherosclerosis

目的:观察中药复方冠心康对载脂蛋白E(apolipoprotein E,ApoE)基因敲除(ApoE-/-)动脉粥样硬化(atherosclerosis,AS)小鼠三磷酸腺苷结合盒转运体A1(ATP-binding cassette transporterA1,ABCA1)通路的影响。方法:70只ApoE-/-小鼠用高脂饲料喂养建立小鼠AS模型。14只C57BL/6J小鼠为正常对照组,给予普通饲料。70只ApoE-/-小鼠造模成功后随机分为5组,即模型组、高剂量冠心康组(生药浓度为3.456g/mL)、中剂量冠心康组(1.728g/mL)、低剂量冠心康组(0.864g/mL)和西药辛伐他汀组[3mg/(kg·d)]。每只小鼠灌胃0.5mL,每天1次。连续灌胃8周后取材,分离肝脏及主动脉。运用蛋白质印迹法检测各组小鼠过氧化物酶体增殖物激活型受体γ(peroxisome proliferator-activated receptorγ,PPARγ)、肝X受体α(liver X receptor α,LXRα)和ABCA1蛋白的表达,实时荧光定量聚合酶链反应法检测各组小鼠主动脉、肝脏PPARγ、LXRα和ABCA1mRNA的表达。结果:与C57BL/6J小鼠比较,ApoE-/-小鼠的主动脉、肝脏的PPARγ、LXRα、ABCA1mRNA的表达明显增高;与模型组小鼠比较,高、中剂量冠心康与辛伐他汀在不同程度上下调了主动脉、肝脏的PPARγ、LXRα、ABCA1mRNA的表达(P<0.05),而以高剂量冠心康的作用最为突出。低剂量组无明显改变(P>0.05)。与C57BL/6J小鼠比较,ApoE-/-小鼠的主动脉、肝脏的PPARγ、LXRα、ABCA1蛋白的表达明显增高;与模型组小鼠比较,各用药组主动脉、肝脏的PPARγ、LXRα、ABCA1蛋白的表达量下降(P<0.05),而以冠心康高剂量组作用最为突出。结论:PPARγ-LXRα-ABCA1通路在ApoE-/-小鼠脂质代谢紊乱、炎症反应方面扮演重要角色。复方冠心康能改善ApoE-/-小鼠动脉粥样硬化过程中的脂质代谢紊乱,抑制炎症反应的进展,可能与调控ApoE-/-小鼠的主动脉、肝脏PPARγ、LXRα、ABCA1 mRNA及蛋白的表达有关。

OBJECTIVE：To observe the effects of Guanxinkang（GXK）decoction,a compound traditional Chinese herbal medicine,on expressions of peroxisome proliferator-activated receptorγ（PPARγ）,liver X receptorα （LXRα）and ATP-binding cassette transporter A1（ABCA1）in apolipoprotein E（ApoE）-knockout mice with atherosclerosis. METHODS：Fourteen 6-week-old C57BL/6 J mice were used as normal control group.Seventy 6-week-old ApoE-knockout mice receiving a high-cholesterol diet to induce atherosclerosis were randomly divided into untreated group,simvastatin group and low-dose（concentration of crude drugs at 0.864 g/mL）,mediumdose（crude drugs at 1.728 g/mL）and high-dose（crude drugs at 3.456 g/mL）GXK groups.After treated with the drugs for eight weeks continuously,the livers and aortas of mice were separated.The expressions of PPARγ,LXRαand ABCA1 were measured by real-time quantitative polymerase chain reaction and Western blotting respectively. RESULTS：Compared with the normal control group,mRNAs and proteins of PPARγ,LXRαand ABCA1 over-expressed in the untreated group（P0.05）.After the treatment,GXK decoction and simvastatin decreased the expressions of PPARγ,LXRαand ABCA1（P0.05）.High-dose GXK decoction had more marked effects than low-and medium-dose GXK and simvastatin. CONCLUSION：The PPARγ-LXRα-ABCA1 pathway is involved in lipid regulation and inflammation activities. Over-expression of the genes has complicated effects on atherosclerosis in ApoE-knockout mice with high- cholesterol diet.GXK decoction has anti-inflammatory and anti-matrix metalloproteinase activities by regulating PPARγ,LXRαand ABCA1interactions in the ApoE-knockout mice.