Université Côte D'Azur, CNRS, INSERM, iBV, Nice, France.
Université Côte D'Azur, INSERM, C3M, Nice, France.
Sci Rep. 2020 Jul 22;10(1):12139. doi: 10.1038/s41598-020-69085-w.
A large number of hepatic functions are regulated by the circadian clock and recent evidence suggests that clock disruption could be a risk factor for liver complications. The circadian transcription factor Krüppel like factor 10 (KLF10) has been involved in liver metabolism as well as cellular inflammatory and death pathways. Here, we show that hepatic steatosis and inflammation display diurnal rhythmicity in mice developing steatohepatitis upon feeding with a methionine and choline deficient diet (MCDD). Core clock gene mRNA oscillations remained mostly unaffected but rhythmic Klf10 expression was abolished in this model. We further show that Klf10 deficient mice display enhanced liver injury and fibrosis priming upon MCDD challenge. Silencing Klf10 also sensitized primary hepatocytes to apoptosis along with increased caspase 3 activation in response to TNFα. This data suggests that MCDD induced steatohepatitis barely affects the core clock mechanism but leads to a reprogramming of circadian gene expression in the liver in analogy to what is observed in other experimental disease paradigms. We further identify KLF10 as a component of this transcriptional reprogramming and a novel hepato-protective factor.
大量的肝脏功能受到生物钟的调节,最近的证据表明,生物钟紊乱可能是肝脏并发症的一个风险因素。昼夜节律转录因子 Krüppel 样因子 10(KLF10)已参与肝脏代谢以及细胞炎症和死亡途径。在这里,我们发现在喂食蛋氨酸和胆碱缺乏饮食(MCDD)导致脂肪性肝炎的小鼠中,肝脂肪变性和炎症显示出昼夜节律性。核心时钟基因 mRNA 振荡基本不受影响,但在该模型中,节律性 Klf10 表达被消除。我们进一步表明,Klf10 缺陷小鼠在 MCDD 挑战时表现出增强的肝损伤和纤维化启动。沉默 Klf10 也使原代肝细胞对 TNFα 反应时的细胞凋亡敏感,同时 caspase 3 激活增加。这些数据表明,MCDD 诱导的脂肪性肝炎几乎不影响核心时钟机制,但会导致肝脏中昼夜基因表达的重新编程,类似于在其他实验性疾病模型中观察到的情况。我们进一步将 KLF10 确定为这种转录重编程的一个组成部分和一种新的肝保护因子。