Sterols are abundant lipids in mammalian cells that maintain the structural integrity of the plasma membrane, form specialized signaling centers termed lipid rafts, and serve numerous regulatory roles as agonists and antagonists of transcription. The diverse functions of sterols, together with their structural complexity, suggest that novel sterols and biological roles remain to be identified for this lipid class. The initial goal of Core J will be to develop lipidomics methods to advance mechanistic understanding of sterol metabolism in the macrophage. Known sterols will be identified and quantitated by LC-MS methods in immortalized and primary macrophages subjected to lipopolysaccharide, cytokine, and phagocytic challenges, or treated with inhibitors of lipid biosynthesis. Novel sterols and other lipids will be identified in these experiments using an LC-MS based metabolomics approach in which comparisons are made between total lipid profiles derived from experimental and control cells. The structures of new lipids will be determined by combined LC-MS and GC-MS analyses, and cDNAs encoding their biosynthetic enzymes will be isolated by expression cloning. The second objective of Core J is to employ lipidomics to investigate the sterol complement of macrophages and tissues under normal and pathological conditions. Sterols will be extracted from cells and tissues isolated from different animal models of disease or diet-induced pathologies and then quantitated by LC-MS. The effects of drugs such as statins and glitazones on sterols levels will be determined in these experiments, and cross-talk between different lipid pathways will be assessed by the above LC-MS based metabolomics approach. Our third goal will be the development of lipid networks and maps from the data generated in the above studies. Sterol and other lipid profiles will be compared to gene expression data generated by microarray analyses to produce a global picture of the lipidome, including the biosynthetic enzymes involved, pathway interactions, and metabolite flows. Stable isotope methods using 13C-mevalonate as a precursor will be developed to provide a detailed understanding of sterol synthesis and turnover. The proposed research will provide new insight into the roles of sterols and other lipids in the macrophage, a cell type that is relevant to immunity, inflammation, and atherosclerosis.

Agency
National Institute of Health (NIH)
Institute
National Institute of General Medical Sciences (NIGMS)
Type
Specialized Center--Cooperative Agreements (U54)
Project #
5U54GM069338-10
Application #
8382528
Study Section
Special Emphasis Panel (ZGM1-CBB-5)
Project Start
Project End
2014-07-31
Budget Start
2012-08-01
Budget End
2013-07-31
Support Year
10
Fiscal Year
2012
Total Cost
$447,089
Indirect Cost
$90,415
Name
University of California San Diego
Department
Type
DUNS #
804355790
City
La Jolla
State
CA
Country
United States
Zip Code
92093
Young, Hayley E; Zhao, Jinshi; Barker, Jeffrey R et al. (2016) Discovery of the Elusive UDP-Diacylglucosamine Hydrolase in the Lipid A Biosynthetic Pathway in Chlamydia trachomatis. MBio 7:e00090
Tribble, Emily K; Ivanova, Pavlina T; Grabon, Aby et al. (2016) Quantitative profiling of the endonuclear glycerophospholipidome of murine embryonic fibroblasts. J Lipid Res 57:1492-506
Bonnington, Katherine E; Kuehn, Meta J (2016) Outer Membrane Vesicle Production Facilitates LPS Remodeling and Outer Membrane Maintenance in Salmonella during Environmental Transitions. MBio 7:
Li, Chijun; Tan, Brandon K; Zhao, Jinshi et al. (2016) In Vivo and in Vitro Synthesis of Phosphatidylglycerol by an Escherichia coli Cardiolipin Synthase. J Biol Chem 291:25144-25153
Guan, Ziqiang; Chen, Lingli; Gerritsen, Jacoline et al. (2016) The cellular lipids of Romboutsia. Biochim Biophys Acta 1861:1076-82
Dennis, Edward A (2016) Liberating Chiral Lipid Mediators, Inflammatory Enzymes, and LIPID MAPS from Biological Grease. J Biol Chem 291:24431-24448
Guan, Ziqiang; Delago, Antonia; Nußbaum, Phillip et al. (2016) N-glycosylation in the thermoacidophilic archaeon Sulfolobus acidocaldarius involves a short dolichol pyrophosphate carrier. FEBS Lett 590:3168-78
Gupta, Shakti; Kihara, Yasuyuki; Maurya, Mano R et al. (2016) Computational Modeling of Competitive Metabolism between ω3- and ω6-Polyunsaturated Fatty Acids in Inflammatory Macrophages. J Phys Chem B 120:8346-53
Dennis, Edward A; Norris, Paul C (2015) Eicosanoid storm in infection and inflammation. Nat Rev Immunol 15:511-23
Crotti, Andrea; Glass, Christopher K (2015) The choreography of neuroinflammation in Huntington's disease. Trends Immunol 36:364-73

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