吡格列酮对糖尿病ApoE-/-小鼠动脉粥样硬化的影响及机制研究

Effect of Pioglitazone on the development of atherosclerosis and its underlying mechanisms in diabetic ApoE-/- mice

目的探讨吡格列酮(PIO)对糖尿病载脂蛋白E基因敲除(ApoE^-/-)小鼠动脉粥样硬化的影响及机制。方法6周龄雄性ApoE^-/-健康小鼠64只,共分为4组,每组16只。C组:非糖尿病ApoE^-/-小鼠,即对照组;其余小鼠连续5 d腹腔内注射链脲佐菌素制备糖尿病模型,糖尿病小鼠分为3组,D组:糖尿病ApoE^-/-小鼠组;D+P组:糖尿病ApoE^-/-小鼠+PIO组;D+P+G组:糖尿病ApoE^-/-小鼠+PIO+GW9662组。过氧物酶体增殖物激活受体-γ(PPAR-γ)激动剂PIO灌胃或PPAR-γ特异性抑制剂GW9662皮下注射连续应用12周。每周测量小鼠的体重,每两周测量小鼠血糖。20周时处死小鼠,分离小鼠主动脉血管。油红O染色评估动脉粥样硬化斑块的面积,Western blotting法和免疫组化评估糖基化终末代谢产物受体(RAGE)和PPAR-γ的表达。结果随着时间的不同,各组小鼠同一时间的体重无显著差异,各组小鼠血糖的变化无显著差异。D组小鼠主动脉粥样硬化斑块面积和RAGE表达高于C组(P<0.05);D+P组小鼠的动脉粥样硬化斑块的面积及RAGE表达显著降低(P<0.05);D+P+G组小鼠的动脉粥样硬化斑块的面积及RAGE表达明显高于D+P组(P<0.05)。结论PIO抑制了糖尿病ApoE^-/-小鼠动脉粥样硬化的发展,抑制RAGE信号是PIO有益作用的关键因素,并且是通过激活PPAR-γ实现的。

Objective To investigate the effect of Pioglitazone(PIO)on the development of atherosclerosis and its underlying mechanisms in diabetic ApoE^-/-mice.Methods 64 6-week-old male ApoE^-/-healthy mice were divided into 4 groups,each group of 16 mice.Control group:Non-diabetic ApoE^-/-mice(C group),Other ApoE^-/-mice were rendered diabetic by 5 daily intraperitoneal injections of streptozotocin at the 6th week.Diabetic mouse were divided into three groups:Diabetic ApoE^-/-mice(Diabetes group,D);Diabetic ApoE^-/-mice with PIO(D+P).Diabetic ApoE^-/-mice with PIO and GW9662(D+P+G).PPAR-γagonist PIO or PPAR-γinhibitor GW9662 were administered for 12 weeks.The body weight was measured weekly and blood sugar was measured every two weeks.At 20th week,mice were killed and the aorta were isolated.Oil Red O staining was used to evaluate atherosclerotic plaque area.Western blotting and immunohistochemistry were used to determine the expression of the receptor of advanced glycation end products(RAGE)and PPAR-γ.Results With the time difference,there was no difference in body weight each group at the same time,and there was no difference in blood glucose of each group.The expression of atherosclerotic plaque area and RAGE in group D was higher than that in group C(P<0.05).The area of atherosclerotic plaque and the expression of RAGE in group D+P were significantly reduced(P<0.05).After GW9662 was applied,the expression of atherosclerotic plaque area and RAGE in group D+P+G was significantly higher than that in group D+P(P<0.05).Conclusion PIO inhibited the development of atherosclerosis in diabetic ApoE^-/-mice.Inhibition of RAGE signaling plays a critical role in mediating the beneficial effects of PIO by activating the expression of PPAR-γ.