不同剂量大豆异黄酮对高脂大鼠小肠胆固醇酰基转移酶2表达的影响

Effects of different doses of soy isoflavones on acyl-CoA:cholesterol acyltransferase-2 expression in small intestine of high fat diet rats

目的探讨不同剂量的大豆异黄酮(soy isoflavone,sI)对高脂大鼠小肠酰基辅酶A:胆固醇酰基转移酶-2(acyl-coenzymeA:cholesterol acyltransferase-2,ACAT2)表达水平的影响.方法雄性Wistar大鼠75只,15只作为正常对照组给予基础饲料,其余60只大鼠给予高脂饲料喂养.高脂喂养4周后,60只大鼠随机分为高脂对照组15只;低剂量SI组(高脂饲料+30 mg/kg/d SI)15只;中剂量SI组(高脂饲料+90 mg/kg/d SI)15只;高剂量SI组(高脂饲料+270 mg/kg/d SI)15只,连续喂养12周后处死大鼠,取大鼠的小肠,采用免疫组化法观察不同剂量的SI对高脂大鼠小肠ACAT2表达水平的影响.结果与正常对照组相比,高脂饲料组大鼠小肠的ACAT2表达水平升高,差异具有统计学意义[(0.0356±0.0175)比(0.3137±0.0758),P<0.05];与高脂饲料对照组相比低剂量SI对大鼠小肠ACAT2表达有抑制作用,但无统计学意义[(0.3137±0.0758)比(0.3066±0.0799),P>0.05];中、高剂量SI对大鼠小肠ACAT2表达有抑制作用,差异具有统计学意义[(0.3137±0.0758)比(0.1795±0.0156),(0.3137±0.0758)比(0.1106±0.0100),P值均<0.05].结论SI对高脂大鼠小肠ACAT2的表达有抑制作用,且有剂量依赖性.

Objective To investigate the effects of different doses of soy isoflavone(SI)on the expression of acyl-CoA:cholesterol acyltransferase-2(ACAT2)in high fat rats.Methods Seventy-five male Wistar rats were included as the normal control group(15 rats)and the other rats(60 rats)that were fed with high fat diet.After 4 weeks,the 60 rats with high-fat diet were randomly divided into high-fat control group(15 rats),low-dose SI group(high-fat diet+30 mg/kg/d SI,15 rats),medium-dose SI group(high-fat diet+90 mg/kg/d SI,15 rats),and high-dose SI groups(high-fat diet+270 mg/kg/d SI,15 rats).After fed for another 12 weeks,the rats were sacrificed to take the small intestines.The effect of different doses of SI on the expression of ACAT2 in high fat rats was detected by immunohistochemistry.Results Compared with the normal control group,the expression of ACAT2 in the small intestine of the high fat diet group was increased[(0.0356±0.0175)vs(0.3137±0.0758),P<0.05].Compared with the high fat diet control group,the small intestine ACAT2 expression in the low dose of SI group was inhibited,but not statistically significant[(0.3137±0.0758)vs(0.3066±0.0799),P>0.05].While the medium and high doses of SI treatment attained a significant inhibition the effect on ACAT2 expression[(0.3137±0.0758)vs(0.1795±0.0156),(0.3137±0.0758)vs(0.1106±0.0100),all P<0.05].Conclusion SI treatment inhibits the expression of ACAT2 in the small intestine of high-fat rats,and the inhibition may have dose-dependent manner.