LPS-induced coagulation and inflammation are important components of the pathogenesis of bacterial sepsis. In the United States, sepsis is the leading cause of death in non-coronary intensive care units. The objective of this proposal is to determine the role of the PI3K-Akt signaling pathway in suppressing LPS- induced coagulation and inflammation. The overall hypothesis is that the PI3K-Akt pathway negatively regulates LPS-induced coagulation and inflammation.
Specific Aim 1 will characterize the role of PI3K-Akt pathway activation in LPS-induced cytokine and tissue factor production by macrophages. We will employ a genetic approach that either increases (PTEN-/-) or decreases (p85alpha-/-) PI3K-Akt pathway activation.
Specific Aim 2 will evaluate whether the inhibitory effect of simvastatin on LPS-induced coagulation and inflammation involves activation of PI3K-Akt signaling. We hypothesize that wortmannin, a PI3K inhibitor, will block the anti-inflammatory and anticoagulant effects of simvastatin in LPS-treated macrophages and in a mouse endotoxemia model. Ultimately, characterization of the involvement of this pathway in LPS-induced inflammation may allow for development of novel strategies that can be used to treat sepsis. ? ? ?
Luyendyk, James P; Schabbauer, Gernot A; Tencati, Michael et al. (2008) Genetic analysis of the role of the PI3K-Akt pathway in lipopolysaccharide-induced cytokine and tissue factor gene expression in monocytes/macrophages. J Immunol 180:4218-26 |
Kidd, Linda B; Schabbauer, Gernot A; Luyendyk, James P et al. (2008) Insulin activation of the phosphatidylinositol 3-kinase/protein kinase B (Akt) pathway reduces lipopolysaccharide-induced inflammation in mice. J Pharmacol Exp Ther 326:348-53 |
Ganey, Patricia E; Luyendyk, James P; Newport, Sandra W et al. (2007) Role of the coagulation system in acetaminophen-induced hepatotoxicity in mice. Hepatology 46:1177-86 |
Luyendyk, James P; Piper, J Daniel; Tencati, Michael et al. (2007) A novel class of antioxidants inhibit LPS induction of tissue factor by selective inhibition of the activation of ASK1 and MAP kinases. Arterioscler Thromb Vasc Biol 27:1857-63 |