Targeting F-box protein 048 in acute lung injury

急性肺损伤（ALI）是退伍军人中常见的一种毁灭性疾病， 败血症或严重肺炎。急性肺损伤的两个主要表现是 提取氧气和炎症，这两者都可能有线粒体的基础。虽然 ALI患者存在线粒体缺陷，这是其损伤的分子机制 干扰氧消耗和引发炎症的机制尚不清楚。机械论 这一建议的基础在于我们发现了一个独特的线粒体的分子模型， 一种新的蛋白质Fbxo 48可以有效地破坏线粒体功能， 通过介导一种重要的细胞保护性抗炎能量的降解来抑制炎症 传感器：5′-AMP-活化蛋白激酶（AMPK）。通过靶向C末端分子 签名存在于Fbxo 48中，我们设计、合成并测试了一种新的小分子， BC-1618，稳定AMPK水平，保留线粒体功能， 小鼠和人ALI模型中的炎症。因此，在本申请中，我们将首先阐明 一种常见的病原体S.金黄色葡萄球菌，通过Fbxo 48消耗AMPK，从而加重 实验性ALI（Aim 1）。我们将具体阐明Fbxo 48如何靶向AMPK， 使用互补的体外和体内遗传模型降解，包括 CRISPR/Cas9 Fbxo 48敲除小鼠。接下来，我们将检查药代动力学， BC-1618的药效学特性，重点是其对肾脏的保护和抗- ALI模型中的炎症特性（目的2）。本应用程序中的一种独特方法是 在离体人肺灌注系统中执行小分子测试。这些 研究将提供一种新的线粒体损伤的病理生物学模型， 提供一流的双作用小分子调节剂的平台， 细胞生物能量学和限制严重危重病受试者的炎症。

Acute lung injury (ALI) is a devastating disorder among Veterans commonly occurring after sepsis or severe pneumonia. Two key manifestations of ALI are a fundamental inability to extract oxygen and inflammation, both of which may have a mitochondrial basis. Although ALI subjects have mitochondrial defects, the molecular mechanisms underlying their injury that disrupt oxygen consumption and trigger inflammation remain unclear. The mechanistic basis of this proposal resides on our discovery of a unique molecular model of mitochondrial injury whereby a new protein, Fbxo48, potently disrupts mitochondrial function to trigger inflammation by mediating degradation of a crucial cytoprotective, anti-inflammatory energy sensor, 5′-AMP-activated protein kinase (AMPK). By targeting the C-terminal molecular signature present in Fbxo48, we designed, synthesized, and tested a novel small molecule, BC-1618, that stabilizes AMPK levels, preserves mitochondrial function, and reduces inflammation in murine and human ALI models. Thus, in this application we will first elucidate how a common pathogen, S. aureus, depletes AMPK through Fbxo48, thereby accentuating experimental ALI (Aim 1). We will specifically elucidate how Fbxo48 targets AMPK for its degradation using complementary in vitro and in vivo genetic models, including CRISPR/Cas9 Fbxo48 knockout mice. Next we will examine the pharmacokinetic and pharmacodynamics properties of BC-1618 focusing on its mitochondrial-protective and anti- inflammatory properties in ALI models (Aim 2). A unique approach in this application is execution of small molecule testing in an ex vivo human lung perfusion system. These studies will provide a new pathobiologic model of mitochondrial injury that will serve as a platform for presenting the first-in-class dual acting small molecule modulator that optimizes cellular bioenergetics and limits inflammation in subjects with severe critical illness.