番茄红素对动脉粥样硬化家兔血脂及低密度脂蛋白受体mRNA表达的影响

Effect of lycopene on the expression of low density lipoprotein receptor mRNA in atherosclerotic rabbits

目的:通过建立家兔动脉粥样硬化模型,观察低密度脂蛋白受体(LDLR)mRNA在实验性动脉粥样硬化家兔主动脉平滑肌细胞和心肌细胞的表达及番茄红素对其表达的影响。方法:采用高脂饲料建立家兔动脉粥样硬化模型,造模60d,从第61d起给予番茄红素进行干预,连续用药40d后,测定血清脂质总胆固醇(TC)、甘油三酯(TG)、高密度脂蛋白(HDL)、低密度脂蛋白(LDL)]含量,采用RT-PCR法检测LDLR在主动脉平滑肌细胞和心肌细胞mRNA的表达。所有数据经SPSS13.0软件进行统计分析。结果:番茄红素大剂量组家兔血清TG含量明显低于模型组(P<0.05),而番茄红素小剂量组与模型组比较差异无显著性。RT-PCR结果表明番茄红素能够抑制家兔主动脉和心脏LDLR mRNA的表达。结论:番茄红素对动脉粥样硬化家兔的血脂和脂蛋白代谢紊乱具有调节作用,其作用机制可能与降低TG浓度、抑制LDLR的表达有关。

OBJECTIVE To explore the pharmacological mechanism of lycopene against atherosclerosis（AS） by detection of the expression of low density lipoprotein receptor （LDLR） mRNA expression on the myocardial cells and aortic smooth cells. METHODS AS animal models were randomized into five groups. The groups were fed with high fatty diet for 60 d except the normal group. Lycopene with different doses was given by intra-gastric administration from the 61d to the end of the experiment. The blood samples were analyzed for total cholesterol （TC）, triglyceride （TG）, high density lipoprotein （HDL）, low density lipoprotein （LDL）. The low density lipoprotein receptor （LDLR） mRNA expression in the aortic smooth muscle cells and heart muscle cells were detected by using RT PCR. SPSS 13.0 software was used to evaluate the difference between the five groups. RESULTS Compared with the model group, the TG level was lower markedly by dietary lycopene at the end of the experiment （P〈0.05）. The LDLR mRNA expression levels in the model group were significantly higher than that in con trol group （P〈0. 01 ）. Lycopene of large dose could decrease the expression level of LDI.R mRNA, with very significant difference when compared with that of model group. CONCLUSION The results suggest that the lycopene may provide significant health benefits by dramatically ameliorating the incidence of atherosclerosis as demonstrated by reducing the TG level. Lycopene can down-regulated the LDLR mRNA expression in the induced AS animal models, which implied that lycopene might prevent the occurrence of AS by regulating the LDLR mRNA expression.