Abstract：
The liver and intestine play a critical role in nutrient absorption, storage, and metabolism. The aim of this study was to evaluate expression pattern of phosphatidylinositol 3-kinase (PI3K)/AKT/mammalian target of the rapamycin (mTOR) signaling pathway that included PI3K, AKT1, mTOR, FoxO1, SREBP-1, PPARα, PTEN and FXR in the maternal liver and duodenum. Ovine livers and duodenums were sampled at day 16 of the estrous cycle, and at days 13, 16 and 25 of gestation, and RT-qPCR, western blot and immunohistochemistry analysis were used to detect mRNA and protein expression. The results showed that expression of PI3K, AKT1, p-mTOR, FoxO1, SREBP-1 and PTEN upregulated in the maternal liver, and PPARα upregulated in the duodenum. However, expression of FoxO1, SREBP-1 and PTEN in the duodenum downregulated during early pregnancy. In addition, expression levels of SREBP-1, PTEN and PPARα in the maternal liver, and PI3K in the duodenum peaked at day 13 of pregnancy. In addition, expression levels of PI3K, p-mTOR and FoxO1 in the liver, and AKT1 and p-mTOR in the duodenum peaked at day 16 of pregnancy. Nevertheless, expression levels of FXR both in the maternal liver duodenum downregulated at days 13 and 16 of pregnancy. In conclusion, early pregnancy regulated expression pattern of PI3K/AKT/mTOR signaling pathway in the ovine liver and duodenum in a pregnancy stage-specific and tissue-specific manner, which may be necessary for the adaptations in maternal hepatic nutrient metabolism and intestinal nutrient absorption early pregnancy.
摘要：
肝脏和肠道在营养吸收中起关键作用，storage,和新陈代谢。这项研究的目的是评估磷脂酰肌醇3-激酶（PI3K）/AKT/哺乳动物雷帕霉素靶（mTOR）信号通路的表达模式，包括PI3K，AKT1,mTOR,FoxO1,SREBP-1,PPARα,母体肝脏和十二指肠中的PTEN和FXR。在发情周期的第16天采样绵羊肝脏和十二指肠，在妊娠的第13、16和25天，和RT-qPCR，免疫印迹法和免疫组化法检测mRNA和蛋白表达。结果表明,PI3K的表达,AKT1,p-mTOR,FoxO1，SREBP-1和PTEN在母体肝脏中上调，和PPARα在十二指肠中上调。然而,FoxO1、SREBP-1和PTEN在妊娠早期十二指肠中的表达下调。此外,SREBP-1、PTEN和PPARα在母体肝脏中的表达水平,十二指肠中的PI3K在妊娠第13天达到峰值。此外,PI3K的表达水平，肝脏中的p-mTOR和FoxO1，十二指肠中的AKT1和p-mTOR在妊娠第16天达到峰值。然而，在妊娠的第13天和第16天，母体肝十二指肠中FXR的表达水平均下调。总之,妊娠早期以妊娠阶段特异性和组织特异性方式调节PI3K/AKT/mTOR信号通路在绵羊肝脏和十二指肠中的表达模式，这可能是孕妇早期肝脏营养代谢和肠道营养吸收的适应所必需的。
