Yuan Ping, Qi Xiaoyu, Song Anping, Ma Mingyue, Zhang Xinbei, Lu Chunfeng, Bian Mianli, Lian Naqi, He Jianling, Zheng Shuguo, Jin Huanhuan
Department of Pharmacology, School of Pharmacy, Wannan Medical College, Wuhu, China.
School of Pharmacy, Nantong University, Nantong, China.
J Cell Mol Med. 2021 Aug;25(15):7354-7366. doi: 10.1111/jcmm.16764. Epub 2021 Jun 30.
Although recent evidence has shown that hepatocyte senescence plays a crucial role in the pathogenesis and development of non-alcoholic fatty liver disease (NAFLD), the mechanism is still not clear. The purpose of this study was to investigate the signal transduction pathways involved in the senescence of hepatocyte, in order to provide a potential strategy for blocking the process of NAFLD. The results confirmed that hepatocyte senescence occurred in HFD-fed Golden hamsters and PA-treated LO2 cells as manifested by increased levels of senescence marker SA-β-gal, p16 and p21, heterochromatin marker H3K9me3, DNA damage marker γ-H2AX and decreased activity of telomerase. Further studies demonstrated that iron overload could promote the senescence of hepatocyte, whereas the overexpression of Yes-associated protein (YAP) could blunt iron overload and alleviate the senescence of hepatocyte. Of importance, depression of lncRNA MAYA (MAYA) reduced iron overload and cellular senescence via promotion of YAP in PA-treated hepatocytes. These effects were further supported by in vivo experiments. In conclusion, these data suggested that inhibition of MAYA could up-regulate YAP, which might repress hepatocyte senescence through modulating iron overload. In addition, these findings provided a promising option for heading off the development of NAFLD by abrogating hepatocyte senescence.
尽管最近的证据表明肝细胞衰老在非酒精性脂肪性肝病(NAFLD)的发病机制和发展中起关键作用,但其机制仍不清楚。本研究的目的是探讨参与肝细胞衰老的信号转导途径,以便为阻断NAFLD进程提供潜在策略。结果证实,在高脂饮食喂养的金黄地鼠和棕榈酸处理的LO2细胞中发生了肝细胞衰老,表现为衰老标志物SA-β-半乳糖、p16和p21、异染色质标志物H3K9me3、DNA损伤标志物γ-H2AX水平升高,以及端粒酶活性降低。进一步研究表明,铁过载可促进肝细胞衰老,而Yes相关蛋白(YAP)的过表达可减轻铁过载并缓解肝细胞衰老。重要的是,在棕榈酸处理的肝细胞中,长链非编码RNA MAYA(MAYA)的抑制通过促进YAP减少了铁过载和细胞衰老。体内实验进一步支持了这些作用。总之,这些数据表明抑制MAYA可上调YAP,这可能通过调节铁过载来抑制肝细胞衰老。此外,这些发现为通过消除肝细胞衰老来阻止NAFLD的发展提供了一个有前景的选择。