Targeting the orphan nuclear receptor LRH-1 with small molecules

项目总结 肥胖在美国日益流行，导致非酒精性脂肪肝病例增加 非酒精性脂肪肝(NAFLD)、心血管疾病和II型糖尿病。这些疾病的一个共同特征是 脂肪和葡萄糖代谢异常。这项建议的核心是核激素受体，即肝脏受体 同系物1(LRH-1)，作为脂代谢的重要调节因子，逆转胆固醇运输， 葡萄糖感应和动态平衡。因此，LRH-1代表了一种新的代谢治疗靶点 疾病。LRH-1与磷脂结合，并被不寻常的磷脂酰磷脂酰胆碱激活 (DLPC)，显示出强大的抗糖尿病作用。LRH-1受PL配体调控的发现揭示了 调节LRH-1活性用于治疗代谢性疾病的令人兴奋的潜力。然而，请不要担心。 不适合临床使用，需要开发小分子激动剂。这证明了 到目前为止具有挑战性的是，因为很少有小分子可以取代大的亲脂的内源性脂肪 捆绑袋。我们实验室最近的研究已经表征了一类具有这种能力的小分子。 壮举。利用强大的合成孔径雷达和创新的化学，我们设计了强大的LRH-1激动剂 生物活性。我们已经修改了我们最有效和最有效的激动剂，以改善它们的生物物理 特性，使其适合于体内研究。LRH-1激动剂作为治疗药物的研究进展 也因缺乏合适的啮齿动物模型来筛选潜在候选人而受到阻碍，因为 啮齿动物与人类LRH-1结合口袋的序列差异。为了克服这一障碍，我们使用了 CRISPR-Cas9策略人源化小鼠LRH-1配体结合口袋。这允许通过以下方式激活 合成激动剂，同时最大限度地减少内源相互作用表面的变化。这些在领先方面的飞跃 化合物开发和小鼠模型生成，结合我们对LRH-1的深入了解 结构和功能，为开发候选的临床前LRH-1调节剂创造了理想的平台 代谢性疾病。在这里，我们制定了一项战略，以确定行动机制、目标参与、 我们的先导化合物的药理作用和疾病功效。在目标1中，我们生成了具有改进的 模拟类PL激活的生物物理性质。我们将对这些进行机械化的描述 化合物探索不同极性部分接触PL结合部位如何改善LRH-1 激活。在目标2中，我们将从ADME的角度研究我们的先导化合物的行为。这个 主要目标将是利用我们的人源化小鼠来确定化合物的可操作性，以便 可以建立药代动力学关系。在目标3中，我们将使用我们的人源化小鼠和一个 评估我们的LRH-1先导化合物改善血糖的体内疗效 耐受性和胰岛素抵抗。

PROJECT SUMMARY Obesity is a growing epidemic in the United States, leading to increases in cases of nonalcoholic fatty liver disease (NAFLD), cardiovascular disease, and type II diabetes. A common characteristic of these diseases is aberrant lipid and glucose metabolism. This proposal centers on the nuclear hormone receptor, Liver Receptor Homolog 1 (LRH-1), which acts as an important regulator of lipid metabolism, reverse cholesterol transport, glucose sensing, and homeostasis. As such, LRH-1 represents a novel therapeutic target for metabolic diseases. LRH-1 binds to phospholipids (PLs) and is activated by the unusual PL dilauroylphosphatidylcholine (DLPC) which shows potent anti-diabetic effects. The discovery that LRH-1 is regulated by PL ligands reveals an exciting potential to tune LRH-1 activity for the treatment of metabolic diseases. However, PLs are labile and not suitable for clinical use, necessitating the development of small molecule agonists. This has proved challenging thus far, since very few small molecules can displace endogenous lipids from the large, lipophilic binding pocket. Recent studies in our lab have characterized a class of small molecules that are capable of this feat. Using robust SAR and innovative chemistry, we have designed potent LRH-1 agonists that display biological activity. We have modified our most potent and efficacious agonists to improve their biophysical properties, making them suitable for in vivo studies. The advancement of LRH-1 agonists as therapeutics has also been hindered by the lack of appropriate rodent models to screen potential candidates due to small sequence differences in the binding pocket of rodent and human LRH-1. To overcome this barrier, we used a CRISPR-Cas9 strategy to humanize the mouse LRH-1 ligand binding pocket. This permits activation by synthetic agonists while minimizing changes to endogenous interaction surfaces. These leaps forward in lead compound development and mouse model generation, in combination with our deep knowledge of LRH-1 structure and function, create an ideal platform to develop candidate preclinical LRH-1 modulators for metabolic disease. Here, we have developed a strategy to define mechanisms of action, target engagement, pharmacology, and disease efficacy of our lead compounds. In aim 1, we generate compounds with improved biophysical properties that mimic PL-like activation. We will perform mechanistic characterization of these compounds to explore how contacting the PL-binding site with different polar moieties improves LRH-1 activation. In aim 2, we will examine the behavior of our lead compounds from an ADME perspective. The primary objective will be to establish tractability of the compounds using our humanized mice, so that pharmacokinetic relationships can be established. In aim 3, we will use our humanized mice and a model of diet-induced obesity to evaluate the in vivo efficacy of our lead LRH-1 compounds to improve glucose tolerance and insulin resistance.