大豆异黄酮对动脉粥样硬化去卵巢大鼠ATP结合盒A1基因表达的影响

目的 探讨不同剂量大豆异黄酮(SI)对动脉粥样硬化去卵巢SD大鼠ATP结合盒A1(ATP binding cassette A1,ABCA1)表达的影响.方法 50只12周龄SPF级雌性SD大鼠,经普通饲料适应喂养1周后,行卵巢切除术.按体重分层随机抽样,选取10只作为基础对照组(A组),全程喂基础饲料;另40只喂高脂饲料,4周后再按血脂水平分层随机分为4组,每组10只,分别为高脂模型组(B组),继续喂高脂饲料;低剂量SI组(高脂饲料+30 mg/kg SI,C组);中剂量SI组(高脂饲料+90 mg/kg SI,D组);高剂量SI组(高脂饲料+270 mg/kg SI,E组).分组后继续喂22周,处死动物,观察主动脉形态学变化,real-time PCR检测主动脉血管壁ABCA1基因的表达,Western blotting测定ABCA1蛋白在肝脏、主动脉血管壁以及小肠组织的表达情况.结果 各组血脂水平:A、B、C、D、E组总胆固醇水平分别为(6.82±0.22)、(15.73±1.51)、(10.77±1.12)、(9.95±1.18)、(9.11±1.12)mmol/L(F=72.882,P<0.01);甘油三酯水平分别为(2.49±0.24)、(0.78±0.13)、(0.39±0.08)、(0.29±0.09)、(0.24±0.09)mmol/L(F=378.515,P<0.01);低密度脂蛋白胆固醇水平分别为(1.29±0.08)、(14.76±1.23)、(8.18±0.80)、(7.85±0.72)、(7.16±0.64)mmol/L(F=320.936,P<0.01);高密度脂蛋白胆固醇水平分别为(1.94±0.18)、(1.04±0.10)、(1.55±0.14)、(1.88±0.17)、(2.11±0.22)mmol/L(F=49.450,P<0.01).各组ABCA1蛋白在小肠、肝脏、血管壁内表达水平:A、B、C、E组ABCA1蛋白在小肠内表达水平(灰度值)为96.577±9.743、5.218±2.048、18.060±5.179、54.725±8.960(F=172.272,P<0.01);在肝脏内表达水平为13.657±2.397、1.361±0.266、7.069±2.264、11.793±2.515(F=37.383,P<0.01);在血管壁中表达水平为6.756±1.310、0.027±0.006、0.035±0.002、7.479±1.520(F=91.999,P<0.01).B组主动脉可见动脉粥样硬化斑块,而饲料中添加SI能有效避免动脉粥样硬化斑块的形成.结论 SI可能是通过降血脂,提高ABCA1表达水平发挥其抗动脉粥样硬化功能.

The effect of soy isoflavones on ATP binding cassette A1 expression level in rats without ovaries with atherosclerotic plaque

Objective To study the effect of soy isoflavones (SI) on ATP binding cassette A1 (ABCA1) expression in rats without ovary with atherosclerosis. Methods After they were raised for a week by given basic feed, the ovaries of 50 12-week old SPF rats were removed. The rats were randomly divided into groups by weight. Ten rats were selected as the basic control group (A) that basic feed was given all through the research. The other 40 rats were given high-fat diets and at the end of 4 weeks, these rats were randomly divided into four groups by blood lipid level: atherosclerotic model group (B) that was given high-fat diets through the research, low isoflavones group (C) that was given high-fat diets plus 30 mg/kg SI, middle isoflavones group (D) that was given high-fat diets plus 90 mg/kg SI, and high isoflavones group (E) that was given high-fat diets plus 270 mg/kg SI. After 22 weeks, all rats were executed to measure morphological change on the aorta wall,assessing the ABCA1 gene expression in aorta wall by real-time PCR and protein expression by Western blotting in aorta wall, small intestine and liver. Results Serum lipid level of A,B,C,D,E groups: TC levels were (6. 82±0. 22), (15.73±1.51), (10. 77±1.12), (9. 95± 1.18), (9. 11±1.12) mmol/L respectively (F=72. 882, P < 0.01); TG levels were: (2.49±0. 24), (0. 78±0. 13), (0.39±0.08), (0. 29±0. 09), (0. 24±0. 09) mmol/L respectively (F=378.515,P< 0. 01); LDL-C levels were (1.29±0. 08), (14. 76±1.23), (8. 18±0. 80), (7. 85±0. 72), (7. 16± 0. 64) mmol/L respectively (F=320. 936, P < 0. 01); HDL-C levels were (1.94±0. 18), (1.04±0. 10), (1.55±0. 14), (1.88±0. 17), (2. 11±0. 22) mmol/L respectively (F=49. 450, P < 0.01). ABCA1 protein expression in intestine, liver and aorta: for A, B, C, E groups in intestine were 96. 577±9. 743, 5. 218±2. 048,18. 060±5.179,54. 725±8. 960, respectively (F=172. 272, P < 0. 01); ABCA1 protein expression in liver of groups of A,B,C,E were: 13. 657±2. 397,1. 361±0. 266,7. 069±2. 264,11. 793±2. 515 respectively (F=37. 383, P < 0. 01); ABCA1 protein expression in aorta of groups A, B, C, E were: 6. 756±1. 310,0. 027±0. 006,0. 035±0. 002 and 7. 479±1. 520 respectively (F=91. 999, P < 0. 01).Compared to basic control group, atherosclerotic plaque could be observed in atherosclerotic model group, and it could be partially reversed by isoflavones addition. Conclusion Soy isoflavones treatment might inhibit atherosclerotic progression by lowering the level of blood lipid and increasing ABCA1 expression.