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.

Public Health Relevance

Pneumonia is a major cause of morbidity and mortality among Veterans and evidence suggest that patients die from overwhelming inflammation and loss of cell energy in the lung. This application investigates a new pathway by which inflammation and loss of chemical energy occurs in pneumonia. Execution of these studies will provide a significantly new conceptual advance in understanding how pneumonia occurs. Importantly, this application tests new drug interventions that set the stage for use of novel therapies for this potentially fatal condition.

Agency
National Institute of Health (NIH)
Institute
Veterans Affairs (VA)
Type
Non-HHS Research Projects (I01)
Project #
5I01CX000105-06
Application #
9656876
Study Section
Respiration (PULM)
Project Start
2009-04-01
Project End
2021-12-31
Budget Start
2019-01-01
Budget End
2019-12-31
Support Year
6
Fiscal Year
2019
Total Cost
Indirect Cost
Name
Veterans Health Administration
Department
Type
DUNS #
033127569
City
Pittsburgh
State
PA
Country
United States
Zip Code
15240