PROJECT SUMMARY
The main objective of this Maximizing Investigators' Research Award (MIRA) is to provide new
mechanistic insight regarding the metabolic stress response to burn trauma. Specifically, the overarching
goal of this research program is to elucidate the role of the mitochondrion in burn-induced
hypermetabolism and metabolic dysfunction. Burns are a leading cause of non-fatal trauma in the United
States. Today, even the most severe burns are survivable. However, burn survivors endure a protracted
recovery, where restoration of function and quality of life are not readily achieved. Accordingly, there is a
pressing need for new strategies that reduce morbidity and hasten the recovery of burn survivors.
Recent data have implicated mitochondria as mediators of the metabolic stress response to burn trauma.
Indeed, altered bioenergetics are thought underlay the hypermetabolic response to burns, and may
contribute to burn-induced insulin resistance, altered lipid metabolism and muscle wasting. Further,
mitochondrial stress appears to impact cellular homeostasis post burn through the formation of oxygen
radicals, and may contribute to the systemic inflammatory response to burns by releasing fragments of
mitochondrial DNA (mtDNA) into the circulation.
This MIRA will support the development of innovative rodent models of isotopically labeled adipose
tissue and skeletal muscle. These models will be leveraged to trace the turnover, redistribution and
oxidation of specific substrates in response to burn injury. By combining these novel models with
deuterium oxide dosing in vivo, we will generate important data regarding synthesis rates of key
mitochondrial proteins in multiple tissues in response to burn trauma. By dovetailing measurements of
substrate flux and mitochondrial carrier protein turnover with direct measures of mitochondrial respiratory
function, proton leak, membrane potential and superoxide formation, we will elucidate the mechanistic
basis of altered bioenergetics and metabolism in response to burn injury. In addition, the utility of ambient
temperature, protonophores and mitochondrial targeted antioxidants as strategies to restore
bioenergetics and metabolic function post burn will also rigorously tested. Furthermore, blood and tissue
samples collected from burn patients will be used to validate preclinical data and to probe the role of
mtDNA in the systemic inflammatory response to burn injury.
By bettering our mechanistic understanding of the metabolic stress response to burns this research
program will contribute new knowledge that may be leveraged to lessen the suffering and promote the
recovery of burn survivors. Moreover, since hypermetabolism is present in other forms critical illness, the
new information generated by this research program may have broader scientific and clinical impact.