不同膳食脂肪酸构成对大鼠肝脏脂代谢相关基因表达的影响

摘要

Objective To investigate the effect of different dietary fatty acid compositions on the mRNA expression of FAS and PPARα in rat liver. Methods 48 female SD rats were fed diets containing 15% fat(wt/wt)in the experimental period. The rats were randomly assigned into 6 groups fed with 6 different diets respectively,containing following fatty acids:saturated fatty acid(SFA) , monounsaturated fatty acid(MUFA) ,n-6 polyunsaturated fatty acid(PUFA) , n-3 PUFA,1:1 n-6/n-3,and controlled the groups for 18 weeks. The mRNA expression of lipid metabolism key gene(such as:FAS,PPARα)was examined by RT-PCR. Results SFA could significantly increase the expression of FAS gene(P<0. 05). MUFA and PUFA could significantly reduce the expression of FAS gene(P<0. 05). The expression of PPARa had no obvious influence by SFA and MUFA. PUFA also could promote the expression of the key enzyme PPARa. Conclusion PUFA could obviously decrease the levels of blood lipids in which the expression of lipid metebolic genes may play key role.%目的 探讨不同膳食脂肪酸构成比对大鼠脂质代谢相关基因FAS及PPARα mRNA表达的影响.方法 将48只雌性SD大鼠随机分成6组,喂养6种不同膳食脂肪酸构成的饲料,即饱和脂肪酸组(SFA组)、单不饱和脂肪酸组(MUFA组)、n-6多不饱和脂肪酸组(n-6 PUFA组)、n-3多不饱和脂肪酸组(n-3 PUFA组)、1∶1 n-6/n-3组及对照组,持续喂养18周.在实验末提取大鼠肝脏组织,利用逆转录-聚合酶链反应(RT-PCR)技术检测大鼠肝脏组织中FAS及PPARα mRNA表达.结果 SFA、MUFA对PPARα的表达无明显影响.与对照组比较,SFA能显著地升高FAS mRNA的表达,而MUFA能显著降低FAS mRNA表达(P＜0.05).对于PUFA,它们调节血脂的效应更加全面,能够显著降低脂质合成中的关键酶FAS的表达同时升高PPARα的表达.结论 PUFA调节血脂的作用机制可能与脂代谢基因FAS和PPARα有关.