Alcohol-induced hepatotoxicity - implications of secretin/secretin receptor axis

酒精相关性肝病（ALD）是慢性肝病的主要原因， 西方国家与肝脏相关的死亡原因。ALD患者可能会出现广泛的 肝脏病理从单纯性脂肪变性到酒精性脂肪性肝炎（ASH）、酒精性肝炎（AH）、肝硬化， 最终导致肝细胞癌已经进行了广泛的研究，以研究 酒精对肝细胞、星状细胞和免疫细胞（包括库普弗细胞）的影响，但目前尚不清楚。 关于酒精如何影响胆管上皮细胞（即，胆管细胞），以及胆管损伤如何 有助于ALD发病的早期和晚期阶段。最近的研究表明， 酒精性肝炎患者会出现过敏反应。我们以前在其他肝细胞模型中已经显示， 促分泌素（Sct）/促分泌素受体（SR）轴上调并在肾小管损伤中起关键作用。 反应/胆汁衰老以及促成肝纤维化。我们的初步数据表明， 胆管反应、胆管衰老、炎症和纤维化在缺乏 SCT/SR轴在ALD发病中起重要作用。我们建议 一种新的中心假设，即SCT/SR信号轴是介导衰老、促纤维化的关键， 胆汁表型，有助于肝脏炎性细胞浸润的进展， 在ALD的发病过程中纤维化。为了验证我们的假设，我们将继续以下内容 明确的目标。在具体目标#1中，我们将确定SCT/SR轴依赖性小管的激活 反应和胆汁衰老在诱导肝脏炎症中起关键作用， 纤维化在ALD发病过程中的作用。在具体目标#2中，我们将评估是否治疗性地抑制肿瘤的生长。 SCT/SR轴可以预防和限制ALD的进展。完成拟议的研究将 阐明SCT/SR轴在促进局部和全身性免疫反应中的作用的翻译机制。 介导神经内分泌/促纤维化胆汁表型激活的反应，胆汁衰老， 在ALD的进展过程中肝胆炎症和纤维化。

Alcohol-associated liver disease (ALD) is a leading cause of chronic liver diseases and the predominant cause of liver-related mortality in Western countries. Patients with ALD may develop a wide spectrum of liver pathologies from simple steatosis to alcoholic steatohepatitis (ASH), alcoholic hepatitis (AH), cirrhosis, and eventually hepatocellular carcinoma. Extensive research has been performed to study the impact of alcohol on hepatocytes, stellate cells, and immune cells including Kupffer cells in ALD, but little is known about how alcohol affects biliary epithelial cells (i.e., cholangiocytes), and how biliary damage may contribute to the early and late stages of ALD pathogenesis. Recent studies have indicated that ductular reaction occurs in patients with alcoholic hepatitis. We have previously shown in other models of hepatic damage that the secretin (Sct)/secretin receptor (SR) axis is upregulated and plays a critical role in ductular reaction/biliary senescence as well as contributes to hepatic fibrosis. Our preliminary data that ALD-induced ductular reaction, biliary senescence, inflammation, and fibrosis were ameliorated in mice lacking the Sct/SR axis, indicating a crucial role for the SCT/SR axis during the pathogenesis of ALD. We propose the novel central hypothesis that the SCT/SR signaling axis is a key for mediating the senescent, profibrogenic biliary phenotype that contributes to the progression of hepatic inflammatory cell infiltration and subsequent fibrosis during the course of the pathogenesis of ALD. To test our hypothesis, we will pursue the following specific aims. In Specific aim #1, we will determine that activation of SCT/SR axis-dependent ductular reaction and biliary senescence plays a key role in the induction of liver inflammation that drives hepatic fibrosis during the pathogenesis of ALD. In specific aim #2, we will evaluate if therapeutic inhibition of the SCT/SR axis can prevent and limit the progression of ALD. Completion of the proposed studies will elucidate the translational mechanism on the role of SCT/SR axis in the promotion of local and systemic responses to mediate activation of neuroendocrine/profibrogenic biliary phenotype, biliary senescence, hepatobiliary inflammation and fibrosis during the progression of ALD.