The leukotrienes constitute a relatively new group of biologically active compounds initially derived from arachidonic acid oxygenated at C-5 in a lipoxygenase catalyzed reaction. The study of these compounds has undergone explosive growth since the description of LTC4 as a slow reacting substance of anaphylaxis due to potential for rapid application of new basic knowledge to the clinical situation. The analytical methodology available to quantitate leukotrienes is somewhat limited, in particular the availability of reference physical chemical technique to validate bioassay or the RIA technique. In this application, we propose to develop sophisticated mass spectrometric techniques for sensitive, precise, and accurate quantitation of 5-HETE, LTB4, LTC4, LTD4 and LTE4 following fundamental studies of negative ion chemical ionization mass spectrometry of pentafluorobenzyl esters of the hydroxy fatty acid lipoxygenase metabolites. Desulfurization and hydrogenation of the sulfido-leukotrienes to 5-hydroxyeicosanoic acid is proposed as a means to sensitively quantitate the myotropic LTs by mass spectrometry. Multiple UV scanning techniques will also be evaluated as a means to obtain characteristic UV spectra from a few nanograms of LTC4. Physicochemical methods developed in this program will be applied to the study of leukotriene biosynthesis in isolated cells stimulated by hypoxia and in clinical samples of lung lavagates from patients with pulmonary hypertension due to various pathophysiological causes. Additional studies are proposed to investigate the chemical degradation of LTC4/D4/E4 catalyzed by iron salts as well as the degradation of LTB4 by hydroxyl and hydroperoxide radical. Investigation of the in vitro and in vivo metabolism of leukotrienes as well as 5-HETE is proposed with structure elucidation of major metabolites as a prime goal. Finally, the chemical structure of an antimyotropic substance (AMS) isolated from lung lavagates which we have recently discovered, will be sought. This substance has been found in the lung of rats treated with monocrotaline in a model of chronic pulmonary hypertension. Human AMS will also be studied in the lavagates of patients with persistent pulmonary hypertension of the newborn. This antimyotropic substance appears to be synthesized in response to chronic pulmonary vasoconstriction and may be an important, previously unrecognized, mediator in pulmonary vascular homeostasis.
| Eun, John C; Moore, Ernest E; Mauchley, David C et al. (2012) The 5-lipoxygenase pathway is required for acute lung injury following hemorrhagic shock. Shock 37:599-604 |
| Berry, Karin A Zemski; Li, Bilan; Reynolds, Susan D et al. (2011) MALDI imaging MS of phospholipids in the mouse lung. J Lipid Res 52:1551-60 |
| Murphy, Robert C; Gaskell, Simon J (2011) New applications of mass spectrometry in lipid analysis. J Biol Chem 286:25427-33 |
| Farias, Santiago E; Heidenreich, Kim A; Wohlauer, Max V et al. (2011) Lipid mediators in cerebral spinal fluid of traumatic brain injured patients. J Trauma 71:1211-8 |
| Talahalli, Ramaprasad; Zarini, Simona; Sheibani, Nader et al. (2010) Increased synthesis of leukotrienes in the mouse model of diabetic retinopathy. Invest Ophthalmol Vis Sci 51:1699-708 |
| Chen, Mei; Lam, Bing K; Luster, Andrew D et al. (2010) Joint tissues amplify inflammation and alter their invasive behavior via leukotriene B4 in experimental inflammatory arthritis. J Immunol 185:5503-11 |
| Sala, Angelo; Folco, Giancarlo; Murphy, Robert C (2010) Transcellular biosynthesis of eicosanoids. Pharmacol Rep 62:503-10 |
| Zarini, Simona; Gijon, Miguel A; Ransome, Aaron E et al. (2009) Transcellular biosynthesis of cysteinyl leukotrienes in vivo during mouse peritoneal inflammation. Proc Natl Acad Sci U S A 106:8296-301 |
| Farias, Santiago; Frey, Lauren C; Murphy, Robert C et al. (2009) Injury-related production of cysteinyl leukotrienes contributes to brain damage following experimental traumatic brain injury. J Neurotrauma 26:1977-86 |
| Steinhauer, Josefa; Gijón, Miguel A; Riekhof, Wayne R et al. (2009) Drosophila lysophospholipid acyltransferases are specifically required for germ cell development. Mol Biol Cell 20:5224-35 |
Showing the most recent 10 out of 76 publications
