Reduced rate of adenosine triphosphate synthesis by in vivo 31P nuclear magnetic resonance spectroscopy and downregulation of PGC-1β in distal skeletal muscle following burn

Abstract

Using a mouse model of burn trauma, we tested the hypothesis that severe bum trauma corresponding to 30% of total body surface area (TBSA) causes reduction in adenosine triphosphate (ATP) synthesis in distal skeletal muscle. We employed in vivo 31P nuclear magnetic resonance (NMR) in intact mice to assess the rate of ATP synthesis, and characterized the concomitant gene expression patterns in skeletal muscle in burned (30% TBSA) versus control mice. Our NMR results showed a significantly reduced rate of ATP synthesis and were complemented by genomic results showing downregulation of the ATP synthase mitochondrial F 1F 0 complex and PGC-1β gene expression. Our findings suggest that inflammation and muscle atrophy in burns are due to a reduced ATP synthesis rate that may be regulated upstream by PGC-1β. These findings implicate mitochondrial dysfunction in distal skeletal muscle following burn injury. That PGC-1β is a highly inducible factor in most tissues and responds to common calcium and cyclic adenosine monophosphate (cAMP) signaling pathways strongly suggests that it may be possible to develop drugs that can induce PGC-1β.