Children's Liver Disease Center, 302 Military Hospital, Beijing, China.
School of Life Sciences, Guangzhou University, Guangzhou, Guangdong, China; Department of Pharmacology and Toxicology, Ernest Mario School of Pharmacy, Rutgers University, Piscataway, NJ, United States.
Dig Liver Dis. 2018 Oct;50(10):1068-1075. doi: 10.1016/j.dld.2018.04.009. Epub 2018 Apr 23.
Emerging evidence has shown that FXR activation ameliorates the development of alcoholic liver diseases (ALD) while whole-body deficiency of FXR in mice leads to more severe ALD. However, it's unknown whether the enhanced susceptibility to ALD development in FXR mice is due to deficiency of hepatic FXR or increased toxicity secondary to increased bile acid (BA) levels. Hepatocyte-specific FXR knockout mice (FXR) present similar BA levels compared to wild-type mice, and are therefore a useful model to study a direct role of hepatic FXR in ALD development. FXR mice were subject to an ALD model with chronic plus binge drinking of alcohol to determine the effects of hepatic FXR deficiency on ALD development. The FXR mice showed an altered expression of genes involved in BA and lipid homeostasis with alcohol treatment. Despite a slightly increased trend in hepatic lipid deposition and collagen accumulation in FXR mice, there were no significant differences in the severity of steatosis, inflammation, or fibrosis between WT and FXR mice. Therefore, these findings indicate that FXR deficiency in hepatocytes might only play a minor role in ALD development. Deficiency of FXR in other non-hepatic tissues and/or increased BA levels resultant from whole-body FXR deficiency might be responsible for more severe ALD development.
新出现的证据表明,FXR 激活可改善酒精性肝病 (ALD) 的发展,而小鼠全身 FXR 缺乏会导致更严重的 ALD。然而,尚不清楚 FXR 小鼠对 ALD 发展的易感性增加是由于肝 FXR 缺乏还是由于胆汁酸 (BA) 水平增加导致的毒性增加。肝细胞特异性 FXR 敲除小鼠 (FXR) 的 BA 水平与野生型小鼠相似,因此是研究肝 FXR 在 ALD 发展中的直接作用的有用模型。用慢性加 binge 饮酒的方法使 FXR 小鼠发生 ALD 模型,以确定肝 FXR 缺乏对 ALD 发展的影响。FXR 小鼠在酒精处理时表现出与 BA 和脂质稳态相关的基因表达改变。尽管 FXR 小鼠的肝脂质沉积和胶原积累略有增加趋势,但 WT 和 FXR 小鼠之间的脂肪变性、炎症或纤维化严重程度无显著差异。因此,这些发现表明肝细胞中 FXR 的缺乏可能仅在 ALD 发展中起次要作用。全身 FXR 缺乏导致的非肝组织中 FXR 缺乏和/或 BA 水平增加可能是导致更严重 ALD 发展的原因。