Enhanced heat shock protein (HSP) expression protects cells and tissues from injury. Further, enhanced HSP expression improves survival in experimental models of critical illness. However, these findings have not been applied in a clinical setting, as laboratory inducers of HSPs are not safe for human administration. Thus, this powerful tool, that may significantly improve clinical outcome, has yet to be utilized. Our laboratory has shown glutamine (GLN) can safely enhance HSP expression in tissues of critically ill and injured animals and established HSP induction is necessary for GLN's beneficial effect following experimental illness. In a trial of critically ill patients we demonstrated GLN enhanced HSP-70 levels, which correlated with improved outcome. However, the mechanism by which GLN induces HSP expression is unknown. We hypothesize GLN induces HSP expression via activation of the O-linked glycosylation pathway (O-GlcNAc), which is known to depend on GLN as a rate limiting substrate. This pathway can activate key transcription factors required for HSP induction. Our preliminary data indicates GLN increases the activity of the O-GlcNAc pathway and nuclear translocation and activation of key inducers of the HSP pathway, such as Sp1 and heat shock factor-1 (HSF-1). Further, siRNA inhibition of one of the key O-GlcNAc pathway enzymes significantly blunts the GLN-mediated increase in HSP expression. The major focus of this proposal is to determine the mechanism by which GLN induces HSP expression. Our hypothesis is GLN acts via transport into the cell and metabolism by the O-GlcNAc pathway to increase O-linked glycosylation of key transcription factors required for HSP gene activation, which then increases the expression of HSPs. To address this hypothesis, we propose three specific aims: This project will utilize cellular and animal models of illness/injury and employ chemical/genetic inhibition of key enzymes in these pathways to address the following specific aims: 1) Evaluate the role of GLN transport and metabolism via the O-GlcNAc pathway in stress/injury. 2) Evaluate via promoter truncation which promoter regions are key for GLN-mediated HSP expression. Then, determine the effect of GLN on nuclear translocation and transactivation of key transcription factors responsible for HSP expression. 3) Evaluate effects of GLN transport, metabolism, and transcriptional activation on the following cellular and in vivo endpoints: a) HSP expression (multiple families of HSPs), b) tissue/cellular injury, and c) cell volume. This project will elucidate how GLN induces HSP expression in clinical illness and injury. We believe GLN will be able to be administered as a pharmacologic agent prior to surgery or at onset of critical illness/tissue injury (with admittance to ICU/emergency room) to enhance HSP expression and improve survival. This project will elucidate how glutamine induces protective heat shock protein expression in clinical illness and injury. We believe glutamine will be able to be administered as a pharmacologic agent prior to surgery or at onset of critical illness/tissue injury (with admittance to ICU/emergency room) to enhance heat shock protein expression and improve survival.

Agency
National Institute of Health (NIH)
Institute
National Institute of General Medical Sciences (NIGMS)
Type
Research Project (R01)
Project #
5R01GM078312-04
Application #
8053290
Study Section
Surgery, Anesthesiology and Trauma Study Section (SAT)
Program Officer
Somers, Scott D
Project Start
2008-05-01
Project End
2013-02-28
Budget Start
2011-03-01
Budget End
2012-02-29
Support Year
4
Fiscal Year
2011
Total Cost
$264,933
Indirect Cost
Name
University of Colorado Denver
Department
Anesthesiology
Type
Schools of Medicine
DUNS #
041096314
City
Aurora
State
CO
Country
United States
Zip Code
80045
Khailova, Ludmila; Baird, Christine H; Rush, Aubri A et al. (2017) Lactobacillus rhamnosus GG treatment improves intestinal permeability and modulates inflammatory response and homeostasis of spleen and colon in experimental model of Pseudomonas aeruginosa pneumonia. Clin Nutr 36:1549-1557
Ziegler, Thomas R; May, Addison K; Hebbar, Gautam et al. (2016) Efficacy and Safety of Glutamine-supplemented Parenteral Nutrition in Surgical ICU Patients: An American Multicenter Randomized Controlled Trial. Ann Surg 263:646-55
Xue, Hongyu; Ren, Wenhua; Denkinger, Melanie et al. (2016) Nutrition Modulation of Cardiotoxicity and Anticancer Efficacy Related to Doxorubicin Chemotherapy by Glutamine and ?-3 Polyunsaturated Fatty Acids. JPEN J Parenter Enteral Nutr 40:52-66
Heyland, Daren K; Elke, Gunnar; Cook, Deborah et al. (2015) Glutamine and antioxidants in the critically ill patient: a post hoc analysis of a large-scale randomized trial. JPEN J Parenter Enteral Nutr 39:401-9
Wischmeyer, Paul E (2015) Ensuring Optimal Survival and Post-ICU Quality of Life in High-Risk ICU Patients: Permissive Underfeeding Is Not Safe! Crit Care Med 43:1769-72
Snider, Julia Thornton; Jena, Anupam B; Linthicum, Mark T et al. (2015) Effect of hospital use of oral nutritional supplementation on length of stay, hospital cost, and 30-day readmissions among Medicare patients with COPD. Chest 147:1477-1484
Preiser, Jean-Charles; van Zanten, Arthur R H; Berger, Mette M et al. (2015) Metabolic and nutritional support of critically ill patients: consensus and controversies. Crit Care 19:35
Wischmeyer, Paul (2015) Glutamine Supplementation in Parenteral Nutrition and Intensive Care Unit Patients: Are We Throwing the Baby Out With the Bathwater? JPEN J Parenter Enteral Nutr 39:893-7
Wischmeyer, Paul E; Dhaliwal, Rupinder; McCall, Michele et al. (2014) Parenteral glutamine supplementation in critical illness: a systematic review. Crit Care 18:R76
Khailova, Ludmila; Petrie, Benjamin; Baird, Christine H et al. (2014) Lactobacillus rhamnosus GG and Bifidobacterium longum attenuate lung injury and inflammatory response in experimental sepsis. PLoS One 9:e97861

Showing the most recent 10 out of 36 publications