燕麦纤维通过LXRα/ABCA1信号通路对小鼠肠道胆固醇代谢影响  

Effect of oat fiber on intestinal cholesterol metabolism through LXRα/ABCA1 signaling pathways in mice

作　　者：张茹[1] 张薇[1] 焦俊[1] 秦立强[1] 韩淑芬[1] ZHANG Ru;ZHANG Wei;JIAO Jun(Department of Nutrition and Food Hygiene, School of Public Health Soochow University, Suzhou, Jiangsu Province 215123, China)

机构地区：[1]苏州大学公共卫生学院营养与食品卫生教研室,江苏苏州215123

出　　处：《中国公共卫生》2018年第6期827-829,共3页Chinese Journal of Public Health

基　　金：国家自然科学基金(81302425);中国营养学会营养科研基金–帝斯曼专项科研基金(CNS-2016097B-3)

摘　　要：目的探讨燕麦纤维对脂代谢紊乱小鼠肠道胆固醇代谢的影响及其机制。方法选用6周龄雄性C57BL/6小鼠36只,按体重随机分为3组:阴性对照组、模型对照组和燕麦纤维组,预防性干预24周。实验结束后,检测血清甘油三酯(TG)、总胆固醇(TC)、低密度脂蛋白胆固醇(LDL-C)、高密度脂蛋白胆固醇(HDL-C)、空腹血糖和胰岛素水平以及肝组织中TG和TC水平。Western blot法测定小肠组织中肝X受体α(LXRα)、三磷酸腺苷结合盒转运子A1(ABCA1)和G1(ABCG1)蛋白的表达水平。结果干预24周后,与模型对照组比较,燕麦纤维组小鼠血清TC、LDL-C水平[分别为(2.02±0.44)、(0.54±0.27)mmol/L]降低,HDL-C水平[(1.05±0.19)mmol/L]升高(P<0.05);燕麦纤维组小鼠空腹血糖[(6.68±1.32)mmol/L)和胰岛素抵抗指数(3.66±1.28)明显下降;燕麦纤维组小鼠小肠上段组织中LXRα、ABCA1、ABCG1蛋白表达量[分别为(0.68±0.14)、(0.96±0.24)、(0.59±0.15)]均明显升高(P<0.05)。结论燕麦纤维可降低脂代谢紊乱小鼠血脂水平,增加肠道胆固醇外流;其机制可能与燕麦纤维上调小肠组织中LXRα、ABCA1和ABCG1的蛋白表达有关。Objective To explore the effect and mechanism of oat fiber on intestinal cholesterol metabolism in C57BL/6 mice fed a high-fat/cholesterol diet. Methods Thirty-six 6-week-old male C57BL/6 mice were randomly divided into three groups according to body weight： negative control group, model control group, and oat fiber group. All the mice were treated for 24 weeks. At the end of the experiment, serum triglycefide （TG）, total cholesterol （TC）, low-density lipoprotein cholesterol （LDL-C）, high-density lipoprotein cholesterol （HDL-C）, fasting blood glucose （FBG） and insulin, and liver homogenate TG and TC were measured. Western blot was used to determine protein expressions involved in intestinal cholesterol metabolism, including liver-X-receptor alpha （LXRα）, adenosine triphosphate-binding cassette A1 and G1 （ABCA1 and ABCG1）. Results Compared with the model control mice, the mice treated with oat fiber had significantly decreased serum TC （2.02 ±0.44 retool/L） and LDL-C （0.54 ± 0.27 retool/L） but increased serum HDL-C （1.05 ± 0.19 mmol/L） （P 〈 0.05 for all） and the mice also had obviously decreased FBG （6.68 ± 1.32 mmol/L） and homeostatic model assessment for insulin resistance （HOMA-IR） （3.66 ± 1.28）. In addition the protein expressions of LXRα （0.68 ± 0.14）, ABCA1 （0.96 ± 0.24） and ABCG1 （0.59 ± 0.15） were upregulated in small intestine tissue of oat fiber treated mice in comparison with those of the mice of the model group （all P 〈 0.05）. Conclusion Oat fiber can improve blood lipid profiles and increase intestinal cholesterol effiux and the effects may be related to upregulations of LXRα, ABCA1 and ABCGI signaling pathways in intestinal tissue.

关 键 词：燕麦纤维 胆固醇外流 LXRα/ABCA1 信号通路 小肠 

分 类 号：R155.52[医药卫生—营养与食品卫生学]