本实验以C57BL/6J小鼠为实验对象,通过建立高血脂模型,喂食不同剂量的岩藻黄素微囊粉,测定了小鼠血清和肝脏中总胆固醇(TC)、甘油三酯(TG)、高密度脂蛋白胆固醇(HDL-C)和低密度脂蛋白胆固醇(LDL-C)的含量,并利用RT-PCR法探讨了岩藻黄素微囊粉对小鼠体内胆固醇代谢的调控作用机制。结果表明岩藻黄素微囊粉能有效降低肝脏中的TC、TG和LDL-C的含量,增加HDL-C的含量;降低血清中TG的含量,增加清血清中HDL-C的含量,同时增加了小鼠粪便中粗脂肪和胆固醇的含量,但在代谢过程中却并没有降低血清中的TC含量。RT-PCR结果显示岩藻黄素微囊粉调节胆固醇代谢的作用机制可能与其能够抑制HMG-COA-R、CYP7A1、LXRα、ABCA1和ACAT2等基因的表达,促进SREBP2、LCAT以及LDLR等基因的表达有关。
An investigation on the effects of fucoxanthin-microencapsulated powder on hypercholesterolemia in high fat-fed C57BL/6J mice was conducted. The mice were fed different doses of fucoxanthin-microencapsulated powder and the serum and liver total cholesterol(TC), triglyceride(TG), high-density lipoprotein cholesterol(HDL-C) content, and low-density lipoprotein cholesterol(LDL-C) content were measured. The regulatory effect of fucoxanthin-microencapsulated powder on cholesterol metabolism in C57BL/6J mice was also investigated using reverse transcription polymerase chain reaction(RT-PCR). The results showed that fucoxanthin-microencapsulated powder effectively reduced the amount of TC, TG, and LDL-C, and increased that of HDL-C, in the liver. TG content in the serum was found to be decreased, while HDL-C levels in the serum increased. The fat and cholesterol content in the stool increased, whereas serum TC content was not decreased in metabolic processes. The results of the RT-PCR showed that the fucoxanthin-microencapsulated powder might regulate the mechanism of cholesterol metabolism by inhibiting the expression of HMG-COA-R, CYP7A1, LXRα, ABCA1, and ACAT2, and promoting the expression of SREBP2, LCAT, and LDLR.