Inflammation is accompanied by a substantial shift in tissue metabolism. One of the major metabolic signatures of inflammation is hypoxia, which is recently appreciated to significantly influence inflammatory disease outcome. Early in the disease process, such "inflammatory hypoxia" results, in large extent, from the recruitment of oxygen demanding inflammatory cell types, particularly neutrophils. In recent years, we have focused on defining targets and molecular pathways set into motion by inflammatory hypoxia. Results from these studies have defined a series of novel signaling mechanisms in which hypoxia (both in vitro and in vivo) drives the metabolism of extracellular nucleotides toward the generation of large amounts of extracellular adenosine. Central to this pathway was the identification of hypoxia-inducible factor (HIF) as an important regulator of the enzymes necessary for Ado metabolism (esp. CD73), thus identifying HIF-regulated Ado production as an endogenous anti-inflammatory pathway. Ongoing studies have revealed that Ado regulates HIF through the active deneddylation of Cullins, a family of proteins critical for the recruitment of ubiquitin ligases. Based on these preliminary studies, we hypothesize that Ado generated early in the inflammatory response functions as a feed-forward anti- inflammatory mechanism through direct actions on mucosal HIF stabilization.
Three specific aims are directed at testing this hypothesis:
In Specific Aim 1, we will define the contribution of neutrophils and epithelia to Ado generation at sites of inflammation.
Specific Aim 2 will extend preliminary data to elucidate mechanisms of Ado-mediated Cullin-2 de-neddylation.
Specific Aim 3 will Probe the role of Ado to HIF-mediated protection. The overall aim of this proposal is to identify novel metabolic signaling by HIF and Ado within the mucosa during inflammatory hypoxia.

Public Health Relevance

This proposal aims at understanding the role of metabolism in mucosal inflammation such as that observed in inflammatory bowel disease (IBD). Results from the studies proposed here will go far to resolve a number of unanswered questions in the field of inflammation, including: What cell types contribute most significantly to the metabolic changes associated with inflammation? Are these metabolic changes protective or detrimental to the tissue? Can these metabolic changes be targeted for therapeutic benefit? Answers to these questions through experiments proposed here will provide an important foundation for which to integrate novel therapeutic approaches for mucosal inflammation.

National Institute of Health (NIH)
National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK)
Research Project (R01)
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Special Emphasis Panel (ZRG1-DKUS-C (03))
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Carrington, Jill L
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University of Colorado Denver
Internal Medicine/Medicine
Schools of Medicine
United States
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Campbell, Eric L; Bruyninckx, Walter J; Kelly, Caleb J et al. (2014) Transmigrating neutrophils shape the mucosal microenvironment through localized oxygen depletion to influence resolution of inflammation. Immunity 40:66-77
Weissmuller, Thomas; Glover, Louise E; Fennimore, Blair et al. (2014) HIF-dependent regulation of AKAP12 (gravin) in the control of human vascular endothelial function. FASEB J 28:256-64
Keely, S; Campbell, E L; Baird, A W et al. (2014) Contribution of epithelial innate immunity to systemic protection afforded by prolyl hydroxylase inhibition in murine colitis. Mucosal Immunol 7:114-23
Kominsky, Douglas J; Campbell, Eric L; Ehrentraut, Stefan F et al. (2014) IFN-?-mediated induction of an apical IL-10 receptor on polarized intestinal epithelia. J Immunol 192:1267-76
Eckle, Tobias; Kewley, Emily M; Brodsky, Kelley S et al. (2014) Identification of hypoxia-inducible factor HIF-1A as transcriptional regulator of the A2B adenosine receptor during acute lung injury. J Immunol 192:1249-56
Eltzschig, Holger K; Bratton, Donna L; Colgan, Sean P (2014) Targeting hypoxia signalling for the treatment of ischaemic and inflammatory diseases. Nat Rev Drug Discov 13:852-69
Colgan, Sean P; Curtis, Valerie F; Campbell, Eric L (2013) The inflammatory tissue microenvironment in IBD. Inflamm Bowel Dis 19:2238-44
Ehrentraut, Stefan F; Kominsky, Douglas J; Glover, Louise E et al. (2013) Central role for endothelial human deneddylase-1/SENP8 in fine-tuning the vascular inflammatory response. J Immunol 190:392-400
Colgan, Sean P; Fennimore, Blair; Ehrentraut, Stefan F (2013) Adenosine and gastrointestinal inflammation. J Mol Med (Berl) 91:157-64
Kelly, C J; Glover, L E; Campbell, E L et al. (2013) Fundamental role for HIF-1* in constitutive expression of human * defensin-1. Mucosal Immunol 6:1110-8

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