Sabath Elizabeth, Salgado-Delgado Roberto, Guerrero-Vargas Natali N, Guzman-Ruiz Mara A, del Carmen Basualdo Maria, Escobar Carolina, Buijs Ruud M
Department of Cell Biology and Physiology, Institute for Biomedical Research, Universidad Nacional Autónoma de México, Mexico City, Mexico.
Department of Anatomy, Faculty of Medicine, Universidad Nacional Autónoma de México, Mexico City, Mexico.
FEBS Lett. 2014 Aug 25;588(17):3104-10. doi: 10.1016/j.febslet.2014.06.045. Epub 2014 Jun 28.
Hepatic circadian transcription, considered to be driven by the liver clock, is largely influenced by food even uncoupling it from the suprachiasmatic nucleus (SCN). In SCN lesioned rats (SCNx) we determined the influence of a physiological feeding schedule on the entrainment of clock and clock-controlled (CCG) genes in the liver. We show that clock genes and the CCG Rev-erbα and peroxisome proliferator-activated receptor alpha (PPARα) in food-scheduled intact and SCNx have a robust diurnal differential expression persisting after a 24h fast. However, hepatic nicotinamide phosphoribosyl transferase (Nampt) shows time dependent changes that are lost in intact animals under fasting; moreover, it is unresponsive to the nutrient status in SCNx, indicating a poor reliance on liver clock genes and highlighting the relevance of SCN-derived signals for its metabolic status-related expression.
肝脏昼夜节律转录被认为是由肝脏生物钟驱动的，即使在与视交叉上核（SCN）解耦的情况下，它也在很大程度上受食物影响。在SCN损伤大鼠（SCNx）中，我们确定了生理进食时间表对肝脏中生物钟基因和生物钟控制基因（CCG）的同步化的影响。我们发现，在定时进食的完整大鼠和SCNx大鼠中，生物钟基因以及CCG类视黄醛X受体α（Rev-erbα）和过氧化物酶体增殖物激活受体α（PPARα）在禁食24小时后仍有强烈的昼夜差异表达。然而，肝脏烟酰胺磷酸核糖转移酶（Nampt）表现出时间依赖性变化，在禁食状态下，这种变化在完整动物中消失；此外，它对SCNx中的营养状态无反应，这表明它对肝脏生物钟基因的依赖性较差，并突出了SCN衍生信号对其代谢状态相关表达的相关性。
