VTechWorks staff will be away for the Thanksgiving holiday beginning at noon on Wednesday, November 27, through Friday, November 29. We will resume normal operations on Monday, December 2. Thank you for your patience.

Browsing by Author "Dennis, Edward A."

Now showing 1 - 2 of 2
  • Thumbnail Image
    Thematic Review Series: Proteomics. An integrated omics analysis of eicosanoid biology
    Buczynski, Matthew W.; Dumlao, Darren S.; Dennis, Edward A. (2009-06-01)
    Eicosanoids have been implicated in a vast number of devastating inflammatory conditions, including arthritis, atherosclerosis, pain, and cancer. Currently, over a hundred different eicosanoids have been identified, with many having potent bioactive signaling capacity. These lipid metabolites are synthesized de novo by at least 50 unique enzymes, many of which have been cloned and characterized. Due to the extensive characterization of eicosanoid biosynthetic pathways, this field provides a unique framework for integrating genomics, proteomics, and metabolomics toward the investigation of disease pathology. To facilitate a concerted systems biology approach, this review outlines the proteins implicated in eicosanoid biosynthesis and signaling in human, mouse, and rat. Applications of the extensive genomic and lipidomic research to date illustrate the questions in eicosanoid signaling that could be uniquely addressed by a thorough analysis of the entire eicosanoid proteome.
  • Thumbnail Image
    TLR-4 and Sustained Calcium Agonists Synergistically Produce Eicosanoids Independent of Protein Synthesis in RAW264.7 Cells
    Buczynski, Matthew W.; Stephens, Daren L.; Bowers-Gentry, Rebecca C.; Grkovich, Andrej; Deems, Raymond A.; Dennis, Edward A. (2007-08-03)
    Arachidonic acid is released by phospholipaseA2 and converted into hundreds of distinct bioactive mediators by a variety of cyclooxygenases (COX), lipoxygenases (LO), and cytochrome P450s. Because of the size and diversity of the eicosanoid class of signaling molecules produced, a thorough and systematic investigation of these biological processes requires the simultaneous quantitation of a large number of eicosanoids in a single analysis. We have developed a robust liquid chromatography/tandem mass spectrometry method that can identify and quantitate over 60 different eicosanoids in a single analysis, and we applied it to agonist stimulated RAW264.7 murine macrophages. Fifteen different eicosanoids produced through COX and 5-LO were detected either intracellularly or in the media following stimulation with 16 different agonists of Toll-like receptors (TLR), G protein-coupled receptors, and purinergic receptors. No significant differences in the COX metabolite profiles were detected using the different agonists; however, we determined that only agonists creating a sustained Ca22+ influx were capable of activating the 5-LO pathway in these cells. Synergy between Ca22+ and TLR pathways was detected and discovered to be independent of NF-κB-induced protein synthesis. This demonstrates that TLR induction of protein synthesis and priming for enhanced phospholipase A2-mediated eicosanoid production work through two distinct pathways.