Hormonal control of NASH development and progression

摘要/摘要 非酒精性脂肪性肝病(NAFLD)包括一系列的病理，从简单的脂肪变性到 非酒精性脂肪性肝炎(NASH-脂肪变性、肝细胞气肿和炎症，有或没有 纤维化)。NASH在肥胖和糖尿病患者中非常普遍，是心血管疾病的独立危险因素 疾病、肝硬变和肝细胞癌，这些破坏性的疾病在退伍军人中比 在普通人群中。育龄妇女患NASH的几率较低；然而，这种保护措施已经丧失。 绝经后当NASH比率等于或超过男性时。临床和实验数据都表明 雌激素在保护女性免受NASH侵袭方面发挥着重要作用。此外，雌激素的保护作用 也可通过组织依赖的雄激素芳构化为雌激素而延伸到男性。尽管有这样的知识， 雌激素介导的保护作用的确切的组织特异性机制尚未被直接研究。 这项建议将集中在雌激素和生长激素(GH)之间的相互关系，特别是在 肝细胞水平，在那里发表的文献和我们小组产生的初步数据导致了 假设雌激素受体、ER和生长激素受体(GHR)是减缓NASH所必需的 发育部分是通过维持肝细胞Stat5b活性来实现的。研究将比较雄性和雌性小鼠与 成人型，肝细胞特异性，雌激素受体敲除，ER或GHR单独，或联合用于： SA_1确定ER-在肝细胞STAT5B作用中的作用及其对肝功能和生理的影响 生长激素受体介导的信号传导的存在和缺失；SA_2决定肝细胞ER是否对饮食有保护作用。 有无生长激素受体诱导的NASH；SA_3决定肝细胞ER和/或生长激素受体是否起作用 在他莫昔芬()诱导的NASH进展中。终点分析包括1)GH轴功能的评估， 全身代谢、肝脏脂肪含量和病理，2)肝脏对急性生长激素刺激的反应(西方 下游细胞内信号的印迹分析和3)肝细胞类型特异性基因的表达 核糖核酸序列(SnRNA-Seq)，一种提供有关潜在串扰的重要信息的技术 肝脏内细胞类型之间的关系，对NASH的发展至关重要。这一项目的成果将产生 识别未来药物靶点以防止男性和女性Nash进展的新机制洞察力 退伍军人。

Abstract/Summary Non-alcoholic fatty liver disease (NAFLD) includes a spectrum of pathologies ranging from simple steatosis to non-alcoholic steatohepatitis (NASH – steatosis, hepatocyte ballooning and inflammation, with or without fibrosis). Highly prevalent in obese and diabetic patients, NASH is an independent risk factor for cardiovascular disease, cirrhosis, and hepatocellular carcinoma, devastating diseases that are more prevalent in veterans than in the general population. Women of reproductive age have lower rates of NASH; however, this protection is lost after menopause when NASH rates equal or exceed those for men. Both clinical and experimental data indicate that estrogen plays a major role in protecting women against NASH. Moreover, the protective effects of estrogen may also extend to men via tissue-dependent aromatization of androgens to estrogens. Despite this knowledge, the precise tissue-specific mechanisms for estrogen-mediated protection have not been directly investigated. This proposal will focus on the interrelationship between estrogen and growth hormone (GH), specifically at the level of the hepatocyte, where published literature and preliminary data generated by our group have led to the HYPOTHESIS that the estrogen receptor, ER, as well as the GH receptor (GHR), are required to slow NASH development in part by sustaining hepatocyte Stat5b activity. Studies will compare male and female mice with adult-onset, hepatocyte-specific, knockdown of the estrogen receptor, ER or GHR alone, or in combination to: SA1 Determine the role of ER in hepatocyte Stat5b action and its impact on hepatic function and physiology in the presence and absence of GHR-mediated signaling; SA2 Determine if hepatocyte ER protects against diet- induced NASH, in the presence and absence of GHR; SA3 Determine if hepatocyte ER and/or GHR play a role in tamoxifen (TAM) induced NASH progression. Endpoint analysis includes assessment of 1) GH-axis function, whole body metabolism, liver lipid content and pathology, 2) Hepatic response to acute GH challenge (western blot analysis of downstream intracellular signals and 3) Hepatic cell-type specific gene expression using single nuclei RNA-Seq (snRNA-Seq), a technique that provides important information on the potential crosstalk between cell types within the liver, critical for NASH development. The outcomes of this project will generate new mechanistic insights to identify future drug targets to prevent NASH progression in both male and female veterans.