Gene Expression Profiling of LPS-Stimulated Murine Macrophages and Role of the NF-?B and PI3K/mTOR Signaling Pathways
Lipopolysaccharide (LPS), a major component of the outer membrane of Gram-negative bacteria, activates a broad spectrum of signaling pathways in immune cells. In this article, RAW264.7 cells have been stimulated for 4 h with 1 ?g/mL of LPS in the presence or not of specific inhibitors of the NF-?B pathway (BAY 11-7082) and the PI3K pathway (LY294002). Gene expression profiles were characterized using the DNA microarray Dual Chip Mouse Inflammation. This array monitors the expression of 233 genes encoding proteins playing a role in inflammation. Both signaling pathways exert an important role in the response to LPS, but they are not completely overlapping. For example, genes encoding the PAF receptor, PAI-1, PlA2 (group V), IL-13 receptor (?2), and GTP cyclohydrolase 1, were upregulated after LPS treatment, but this upregulation was counteracted by LY294002. The same was observed for BAY 11-708
lps nf-?b pi3k/mtor microarrays