PPARγ激动剂和MEK1/2抑制剂药物组合对ApoE^(-/-)小鼠动脉粥样硬化发展的抑制作用

The Combination of Peroxisome Proliferator Activated Receptor Ligand and MEK1/2 Inhibitor Inhibits the Development of Atherosclerosis in ApoE Deficient Mice

目的研究过氧化体增殖物激活型受体γ(PPARγ)激动剂吡格列酮及MEK1/2抑制剂U0126药物组合对雄性载脂蛋白E基因敲除(ApoE-/-)小鼠动脉粥样硬化的抑制作用,并初步探讨药物组合抑制动脉粥样硬化的机制。方法 ApoE-/-小鼠随机分为高脂喂养的对照组、吡格列酮喂药组和U0126与吡格列酮组合喂药3组。药物处理16周之后,将小鼠安乐死,收集血清,检测血清中总胆固醇(TC)、高密度脂蛋白胆固醇(HDLC)、低密度脂蛋白胆固醇(LDLC)和甘油三酯(TG)的含量;剥离小鼠全主动脉并制备主动脉根部冰冻切片,油红O染色检测斑块大小;小鼠肝脏组织冰冻切片后油红O染色,提取肝脏组织中的脂类,定量检测TG含量。结果药物处理没有明显的副作用,同时血清脂质水平和肝脏TG含量没有显著的影响。吡格列酮抑制雄性ApoE-/-小鼠动脉粥样硬化的发展,而吡格列酮与U0126组合喂药则进一步抑制动脉粥样硬化斑块。吡格列酮与U0126药物组合增加斑块弹性蛋白和胶原蛋白的含量,从而可增加斑块的稳定性。结论吡格列酮和U0126药物组合抑制动脉粥样硬化的发展而不引起肝损伤及肝脏脂肪性病变等副作用。我们的结果揭示了一种新的治疗动脉粥样硬化方法。

Aim To study the effect of the combined peroxisome proliferator activated receptor（ PPAR） ligand（ pioglitazone） and MEK1 /2 inhibitor（ U0126） on the development of atherosclerosis in ApoE deficient（ ApoE^- /-） mice and define the underlying mechanisms. Methods Male ApoE^- /-mice（ 8 Week-old） were randomly divided into three groups and received the following treatment： high fat diet（ HFD）,HFD containing pioglitazone,HFD containing pioglitazone plus U0126. The treatment was lasted for 16 weeks with routine check of food intake,water drinking and bodyweight gain. At the end of treatment,all the mice were anesthetized and euthanized in a CO2 chamber followed by collection of blood,aorta and liver. The serum was prepared followed by determination of triglycerides（ TG）,total cholesterol,HDL-cholesterol and LDL-cholesterol levels using commercially available enzymatic kits. The 5 μm frozen sections of aortic root were prepared,and lesions in enface aorta and the aortic root cross sections were determined by oil red O staining.The liver frozen sections were prepared and used to determine hepatic lipid content by oil red O staining. A piece of liver（ ~ 50 mg） was used to extract total lipids followed by TG quantitative analysis. Results The treatment had little effect on serum lipid profiles as well as hepatic TG levels. However,pioglitazone significantly inhibited the development of atherosclerosis and the inhibition was enhanced by adding U0126. The combined pioglitazone and U0126 increased lesion stability by increasing collagen and elastin content in aortic wall. Conclusions The combined pioglitazone and U0126 inhibits the development of atherosclerosis without side effects,such as fatty liver disease and liver damage. Our results provide a new approach for treatment of atherosclerosis.