Metabolic disturbances remain a significant cause of morbidity and mortality of burn patients, despite advancements in the resuscitation and surgical treatment. These aberrations include hypermetabolism, protein catabolism, aberrant fuel preference (predominant oxidafion of fatty acid over glucose), and muscle wasting. Insulin resistance has been postulated as a key player in burn-induced metabolic derangements. Conversely, metabolic derangements have been proposed as an inducer and/or enhancer of insulin resistance, as well. The IRS-1-Akt-Fox01/3 pathway plays a central role in metabolic acfions of insulin in skeletal muscle. Activation of Fox01/3 promotes protein degradation and muscle wasting, and inhibits glucose oxidation in skeletal muscle. In addition to attenuated Akt activity, FoxO transcription factors are activated by MST1 protein kinase and O-glycosylation. The preliminary data in skeletal muscle of burn patients and burned rodents indicate that: (1) IRS-1 expression is suppressed, while the expression of PTP- 1B, a negative regulator of insulin signaling, is increased;(2) serine phosphorylation of IRS-1 is increased: and (3) activities of FoxOI/3 and expression ofthe target genes of FoxOs are increased along with decreased Akt activity and increased stimulatory signals (MST1 activity, O-glycosylation). Based on previous studies and our solid preliminary data, we hypothesize that activation of FoxOI/3, which results from attenuated Akt activity, increased MST1 activity, and O-glycosylation, plays an important role in burn injuryinduced metabolic derangements, and that FoxOs-mediated metabolic disturbances contribute to exacerbafion of impaired IRS-l-mediated insulin signaling in skeletal muscle after burn injury.
Specific Aim 1 will establish attenuated IRS-1-mediated signaling, and clarify serine/threonine phosphorylation status of IRS-1 in muscle of burn patients.
Specific Aim 2 will determine the role of FoxOI and Fox03 in metabolic derangements, specifically muscle wasting and oxidation of glucose versus fatty acid, and in impaired IRS-1- Akt signaling in muscle of burn patients and burned mice, using muscle-specific FoxOI or Fox03 knockout mice.
Specific Aim 3 will determine the safety and efficacy of antisense morpholino oligomers (PMOs) targeting PTP-1 B, FoxOI, and Fox03 in burned mice. Rhesus monkeys, and burn patients. This project is designed to determine whether PTP-1 B, FoxOI, and Fox03 are clinically relevant molecular targets to reverse insulin resistance and metabolic disturbances in burn patients. The proposed studies are expected to develop a new antisense PMO-based therapeutic strategy to improve the outcome of burn patients.

Public Health Relevance

Metabolic disturbances remain a signficant cause of morbidity and mortality in burn patients. New knowledge gained in this project should promote potential new genomic-based therapeutics to reduce the complications associated with dysregulated metabolism in burn patients.

Agency
National Institute of Health (NIH)
Institute
National Institute of General Medical Sciences (NIGMS)
Type
Specialized Center (P50)
Project #
2P50GM021700-32A1
Application #
8414941
Study Section
Special Emphasis Panel (ZGM1-SRC-5 (TB))
Project Start
Project End
Budget Start
2013-06-01
Budget End
2014-05-31
Support Year
32
Fiscal Year
2013
Total Cost
$409,112
Indirect Cost
$101,729
Name
Massachusetts General Hospital
Department
Type
DUNS #
073130411
City
Boston
State
MA
Country
United States
Zip Code
02199
Zhao, Gaofeng; Yu, Yong-Ming; Kaneki, Masao et al. (2015) Simvastatin reduces burn injury-induced splenic apoptosis via downregulation of the TNF-?/NF-?B pathway. Ann Surg 261:1006-12
Watada, Susumu; Yu, Yong-Ming; Fischman, Alan J et al. (2014) Evaluation of intragastric vs intraperitoneal glucose tolerance tests in the evaluation of insulin resistance in a rodent model of burn injury and glucagon-like polypeptide-1 treatment. J Burn Care Res 35:e66-72
Zhao, Gaofeng; Yu, Yong-Ming; Shoup, Timothy M et al. (2014) Membrane potential-dependent uptake of 18F-triphenylphosphonium--a new voltage sensor as an imaging agent for detecting burn-induced apoptosis. J Surg Res 188:473-9
Carter, Edward A; Paul, Kasie; Bonab, Ali A et al. (2014) Effect of exercise on burn-induced changes in tissue-specific glucose metabolism. J Burn Care Res 35:470-3
Lee, Sangseok; Yang, Hong-Seuk; Sasakawa, Tomoki et al. (2014) Immobilization with atrophy induces de novo expression of neuronal nicotinic *7 acetylcholine receptors in muscle contributing to neurotransmission. Anesthesiology 120:76-85
Fu, Glenn K; Xu, Weihong; Wilhelmy, Julie et al. (2014) Molecular indexing enables quantitative targeted RNA sequencing and reveals poor efficiencies in standard library preparations. Proc Natl Acad Sci U S A 111:1891-6
Khan, Mohammed A S; Sahani, Nita; Neville, Kevin A et al. (2014) Nonsurgically induced disuse muscle atrophy and neuromuscular dysfunction upregulates alpha7 acetylcholine receptors. Can J Physiol Pharmacol 92:1-8
Ueda, Masashi; Iwasaki, Hajime; Wang, Shuxing et al. (2014) Cannabinoid receptor type 1 antagonist, AM251, attenuates mechanical allodynia and thermal hyperalgesia after burn injury. Anesthesiology 121:1311-9
Ibrahim, Amir; Fagan, Shawn; Keaney, Tim et al. (2014) A simple cost-saving measure: 2.5% mafenide acetate solution. J Burn Care Res 35:349-53
Shank, Erik S; Martyn, Jeevendra A; Donelan, Mathias B et al. (2014) Ultrasound-Guided Regional Anesthesia for Pediatric Burn Reconstructive Surgery: A Prospective Study. J Burn Care Res :

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