Department of Gene Therapy and Hepatology, Center for Applied Medical Research (CIMA), University of Navarra (UNAV), Pamplona, Spain.
Navarra Institute for Health Research (IdiSNA), Pamplona, Spain.
Cell Death Dis. 2019 Jan 8;10(1):14. doi: 10.1038/s41419-018-1243-0.
Liver cirrhosis results from chronic hepatic damage and is characterized by derangement of the organ architecture with increased liver fibrogenesis and defective hepatocellular function. It frequently evolves into progressive hepatic insufficiency associated with high mortality unless liver transplantation is performed. We have hypothesized that the deficiency of critical nutrients such as essential omega-3 fatty acids might play a role in the progression of liver cirrhosis. Here we evaluated by LC-MS/MS the liver content of omega-3 docosahexaenoic fatty acid (DHA) in cirrhotic patients and investigated the effect of DHA in a murine model of liver injury and in the response of hepatic stellate cells (HSCs) (the main producers of collagen in the liver) to pro-fibrogenic stimuli. We found that cirrhotic livers exhibit a marked depletion of DHA and that this alteration correlates with the progression of the disease. Administration of DHA exerts potent anti-fibrogenic effects in an acute model of liver damage. Studies with HSCs show that DHA inhibits fibrogenesis more intensely than other omega-3 fatty acids. Data from expression arrays revealed that DHA blocks TGFβ and NF-κB pathways. Mechanistically, DHA decreases late, but not early, SMAD3 nuclear accumulation and inhibits p65/RelA-S536 phosphorylation, which is required for HSC survival. Notably, DHA increases ADRP expression, leading to the formation of typical quiescence-associated perinuclear lipid droplets. In conclusion, a marked depletion of DHA is present in the liver of patients with advanced cirrhosis. DHA displays anti-fibrogenic activities on HSCs targeting NF-κB and TGFβ pathways and inducing ADPR expression and quiescence in these cells.
肝硬化是由慢性肝损伤引起的,其特征是器官结构紊乱,肝纤维化增加,肝细胞功能受损。除非进行肝移植,否则它通常会发展为进行性肝衰竭,伴有高死亡率。我们假设,关键营养物质(如必需的欧米伽-3 脂肪酸)的缺乏可能在肝硬化的进展中起作用。在这里,我们通过 LC-MS/MS 评估了肝硬化患者肝脏中欧米伽-3 二十二碳六烯酸(DHA)的含量,并研究了 DHA 在肝损伤的小鼠模型中的作用,以及在肝星状细胞(HSCs)(肝脏中胶原的主要产生细胞)对促纤维化刺激的反应中的作用。我们发现,肝硬化肝脏中 DHA 明显耗竭,这种改变与疾病的进展相关。DHA 的给药在急性肝损伤模型中具有很强的抗纤维化作用。HSCs 的研究表明,DHA 比其他欧米伽-3 脂肪酸更强烈地抑制纤维化。表达谱分析的数据表明,DHA 阻断 TGFβ和 NF-κB 途径。从机制上讲,DHA 减少晚期,但不减少早期,SMAD3 核积累,并抑制 p65/RelA-S536 磷酸化,这是 HSC 存活所必需的。值得注意的是,DHA 增加 ADRP 的表达,导致典型的静止相关核周脂质滴的形成。总之,在晚期肝硬化患者的肝脏中存在明显的 DHA 耗竭。DHA 对 HSCs 具有抗纤维化活性,靶向 NF-κB 和 TGFβ 途径,并诱导这些细胞中 ADPR 的表达和静止。