高胆固醇摄入对新西兰兔胆汁酸代谢的影响

 目的 观察2周高胆固醇食物摄入对新西兰兔胆汁酸经典合成途径基因调节的影响。方法 20只新西兰兔随机分为对照组和高胆固醇组，分别喂饲普通兔粮及高胆固醇兔粮2周，测定实验前后血清总胆固醇（TC）、低密度脂蛋白（LDL）、胆汁酸（bile acid，BA）及肝脏胆固醇7α羟化酶（cholesteral 7α-hydroxylase，CYP7A1）活性及mRNA、小分子异源二聚体伴侣（short heterodimer partner，SHP）mRNA、胆盐输出泵（bile salt export pump，BSEP）mRNA和三磷酸腺苷结合盒转运蛋白A1（ATP-binding cassette transporter A1，ABCA1）mRNA、胆固醇酯转移蛋白（cholesteryl-ester transfer protein，CETP）mRNA。结果 高胆固醇组TC、LDL、BA均较对照组升高（P<0.05）；高胆固醇组CYP7A1活性及mRNA均较对照组降低（P<0.05）；高胆固醇组SHP mRNA、BSEP mRNA均较对照组升高（P<0.05）；胆固醇组ABCA1 mRNA、CETP mRNA均较对照组升高。结论 高胆固醇摄入后肝脏FXR、LXR受体均被激活，CYP7A1活性下降，胆汁酸经典合成减少。

Effects of dietary cholesterol intake on bile acids metabolism in New Zealand white rabbits

Objective To detect the effect of 2-week dietary cholesterol intake on bile acids classic synthesis pathway in New Zealand white rabbits. Methods Twenty New Zealand white rabbits were divided into two groups randomly: control group and cholesterol group. Each group contained 10 rabbits. The control group was fed regular forage, and the cholesterol group was fed 2% cholesterol forage. Serum TC, LDL, bile acid (BA), hepatic cholesteral 7α-hydroxylase (CYP7A1) activity and mRNA, short heterodimer partner (SHP) mRNA and bile salt export pump (BSEP) mRNA, ATP-binding cassette transporter A1 (ABCA1) mRNA and cholesteryl-ester transfer protein (CETP) mRNA were measured. Results Serum TC, LDL and BA were higher in cholesterol group compared with those in control group (P<0.05). Hepatic CYP7A1 activity and mRNA in cholesterol group were higher than those in the control group (P<0.05). Hepatic SHP mRNA, BSEP mRNA were elevated in cholesterol group compared with those in the control group (P<0.05). Hepatic ABCA1 mRNA and CETP mRNA were elevated in cholesterol group compared with those in the control group (P<0.05). Conclusions Dietary cholesterol intake activates hepatic nuclear receptor FXR and LXR, decreases CYP7A1 activity and bile acid classic systhesis.