We have previously shown that prostacyclin activity is regulated b serum proteins. Serum protein stabilizes PGI2 probably through its binding to serum macromolecules. Defective PGI2 binding has been demonstrated in patients with thrombotic stroke and microvascular thrombosis. Physiological significance of abnormal binding activity remains unclear. Using a stable analog of PGI2, i.e. iloprost, we have shown that serum binding to PGI2 in a saturable manner with a KD of 7 x 10-5. Serum albumin binds to iloprost at a similar KD. Our previous studies have indicated that binding of PGI2 cannot be ascribed to albumin entirely. We plan to elucidate the mechanism by which binding occurs in serum. We plan to purify binding proteins from the serum, characterize the structural-functional relationship using novel probes. Once binding proteins are purified, we plan to produce monoclonal antibodies and develop sensitive assay for detection of the defect. The antibodies will be used for probing the structural abnormalities. Fluorescent probes such as 2, 6 dichloroaminophenol iloprost will be employed to determine binding abnormalities in thrombotic stoke. The purified protein or co-factor will be used to determine the interaction between binding proteins and the target cell, i.e. platelets. We plan to purify platelet PGI2, receptor and characterize the receptor protein and determine the active sites by novel probes. This will allow us to study the interaction between PGI2 binding proteins, PGI2 and receptors at the molecular level. PGI2 receptor defects in stroke patients will be studied. These studies will enhance our understanding of the molecular defects leading to stroke and provide a more direct means to develop new therapeutic strategies in controlling stroke and tissue typing.

National Institute of Health (NIH)
National Institute of Neurological Disorders and Stroke (NINDS)
Specialized Center (P50)
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Chen, Pei-Feng; Wu, Kenneth K (2009) Two synthetic peptides corresponding to the proximal heme-binding domain and CD1 domain of human endothelial nitric-oxide synthase inhibit the oxygenase activity by interacting with CaM. Arch Biochem Biophys 486:132-40
Wu, Jui-Sheng; Cheung, Wai-Mui; Tsai, Yau-Sheng et al. (2009) Ligand-activated peroxisome proliferator-activated receptor-gamma protects against ischemic cerebral infarction and neuronal apoptosis by 14-3-3 epsilon upregulation. Circulation 119:1124-34
Liou, Jun-Yang; Ellent, David P; Lee, Sang et al. (2007) Cyclooxygenase-2-derived prostaglandin e2 protects mouse embryonic stem cells from apoptosis. Stem Cells 25:1096-103
Liou, Jun-Yang; Lee, Sang; Ghelani, Dipak et al. (2006) Protection of endothelial survival by peroxisome proliferator-activated receptor-delta mediated 14-3-3 upregulation. Arterioscler Thromb Vasc Biol 26:1481-7
Cieslik, Katarzyna A; Deng, Wu-Guo; Wu, Kenneth K (2006) Essential role of C-Rel in nitric-oxide synthase-2 transcriptional activation: time-dependent control by salicylate. Mol Pharmacol 70:2004-14
Deng, Wu-Guo; Tang, Shao-Tzu; Tseng, Hui-Ping et al. (2006) Melatonin suppresses macrophage cyclooxygenase-2 and inducible nitric oxide synthase expression by inhibiting p52 acetylation and binding. Blood 108:518-24
Wu, Kenneth K (2006) Analysis of protein-DNA binding by streptavidin-agarose pulldown. Methods Mol Biol 338:281-90
Lin, Teng-Nan; Cheung, Wai-Mui; Wu, Jui-Sheng et al. (2006) 15d-prostaglandin J2 protects brain from ischemia-reperfusion injury. Arterioscler Thromb Vasc Biol 26:481-7
Wu, Kenneth K (2006) Transcription-based COX-2 inhibition: a therapeutic strategy. Thromb Haemost 96:417-22
Liou, Jun-Yang; Aleksic, Nena; Chen, Shu-Fen et al. (2005) Mitochondrial localization of cyclooxygenase-2 and calcium-independent phospholipase A2 in human cancer cells: implication in apoptosis resistance. Exp Cell Res 306:75-84

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