摘要
本研究旨在探讨SIRT1基因在鸡肝脏脂类代谢中的功能。采用荧光定量PCR和免疫印迹检测34日龄广西三黄鸡在禁食24 h之后肝内SIRT1及其他糖脂代谢相关基因的表达水平,并测定血糖、血脂变化;检测SIRT1低表达的LMH-gSmiR30细胞系在葡萄糖和棕榈酸处理后细胞内糖脂代谢相关基因的表达水平及胞内脂滴的形成。结果表明:禁食24 h后,血液中甘油三酯浓度显著降低,肝内SIRT1基因的mRNA和蛋白水平显著增加,PGC-Lα、PPARα和ATGL基因表达也显著增加,但FASN基因表达则显著下降;禁食24 h后恢复2h采食,血糖和血液中甘油三酯浓度迅速回升,而肝内SIRT1、PGC-Lα、PPARα和ATGL基因的mRNA水平迅速降至正常喂饲组水平,FASN基因的mRNA水平则回升至对照组的25%;ATGL在SIRT1基因低表达的LMH-gSmiR30细胞中的mRNA表达水平略低于对照组细胞LMH-pmirG中的表达,而高浓度的葡萄糖和棕榈酸对LMH-gSmiR30细胞中ATGL的mRNA表达抑制更为明显,而且细胞内脂滴显著增多。以上结果说明,鸡肝脏中SIRT1基因的表达受营养状态的调控,同时SIRT1基因影响着肝细胞内脂类代谢过程。
引文
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