降脂抗氧化合剂对ApoE-/-小鼠5-脂氧化酶通路表达的影响

目的:探讨降脂抗氧化合剂对ApoE基因敲除小鼠(ApoE-/-小鼠)5-脂氧化酶(5-LO)通路表达的影响。方法:采用高脂饲料连续喂养12周ApoE-/-小鼠,建立动脉粥样硬化动物模型,将已经形成动脉粥样硬化的ApoE-/-小鼠分为模型对照组、降脂抗氧化合剂低剂量组、降脂抗氧化合剂高剂量组、阳性药(辛伐他汀)对照组,每组10只。同时选用同遗传背景正常C57BL/6J小鼠10只,作为正常对照组,予饲喂普通饲料。阳性药(辛伐他汀)对照组以0.05 g·kg-1·d-1ig,降脂抗氧化合剂低、高剂量组分别含生药17.41,69.66 g·kg-1·d-1ig,正常对照组及模型对照组分别给予同体积的蒸馏水,连续ig 28 d后,心脏取血用于酶联免疫测定,取腹主动脉,采用HE染色对腹主动脉的形态学改变进行观察;提取腹主动脉RNA,进行RT-PCR检测5-LO基因的表达量;同时采用ELISA方法检测血清中白三烯B4(LTB4)及白三烯D4(LTD4)的蛋白含量。结果:与正常组比较,模型组的动脉硬化病变、组织5-LO、血清LTB4及LTD4水平都有明显加重或升高(P<0.01)。与模型组比较,高剂量的降脂抗氧化合剂较低剂量的降脂抗氧化合剂可以更显著下调5-LO的基因表达量(P<0.01),病理切片HE染色显示给药降脂抗氧化合剂后,高剂量给药组血管的组织形态较模型组有明显改变,和阳性药组结果类似,显示出药物对动脉粥样硬化具有较好的治疗效果;血清ELISA法结果显示高剂量的降脂抗氧化合剂可以显著降低血液LTB4及LTD4水平,与模型组间比较差异显著(P<0.01)。结论:降脂抗氧化合剂可降低组织5-LO的水平,改善动脉粥样硬化血管组织形态,减少脂质沉积,还可以降低血清LTB4及LTD4水平,改善炎症,达到治疗动脉粥样硬化的目的。

Effect of Jiangzhi Kangyanghua Mixture on Expression of 5-lipoxygenase Pathway in Apolipoprotein E-deficient Mice

Objective: To invesigate the effect of Jiangzhi Kangyanghua mixture on expression of 5-lipoxygenase(5-LO) pathway in apolipoprotein E-deficient mice (ApoE^-/-mice). Method: Male ApoE^-/- mice(n=40;8 weeks old) were obtained and were given a high-fat diet. These mice were divided into four groups as follows:model group,low dose of Jiangzhi Kangyanghua mixture group(17.41 g·kg^-1·d^-1),high dose of Jiangzhi Kangyanghua mixture group(69.66 g·kg^-1·d^-1) and positive drug group (simvastatin, 0.05 g·kg^-1·d^-1). The ten normal C57BL/6J mice with same genetic background were as normal control group,fed with common diet. All mice were administered orally for a month. Then, all mice were killed, the serum and abdominal aorta were saved. HE stating of abdominal aorta was established, also 5-LO mRNA expression level was detected by RT-PCR. The serum protein of leukotrienes B4 (LTB4) and leukotrienes D4(LTD4) were detected by ELISA. Result: The gene and protein expressions of 5-LO in the aortic plaques(P<0.01),as well as the serum levels of LTB4 and LTD4(P<0.01) in atherosclerosis group were markedly increased compared with those of the normal control group. Compared with the model group, the expression of Jiangzhi Kangyanghua mixture of high dose could significantly down regulate 5-LO gene (P<0.01), pathological section HE staining showed that the high dose Jiangzhi Kangyanghua mixture changed obviously vascular tissue compared with the model group, which was similar to the positive drug group, showing the mixture had a good therapeutic effect on atherosclerosis;ELISA results showed the high dose Jiangzhi Kangyanghua mixture could significantly reduce the blood LTB4 and LTD4 levels, compared with the model group (P<0.01). Conclusion: These findings demonstrate that Jiangzhi Kangyanghua mixture can reduce the 5-LO level, improve the morphology of atherosclerotic vascular, reduce lipid deposition, but also can reduce the serum LTB4 and LTD4 levels.