title: Phosphatidic acid as a regulator of matrix metalloproteinase-9 expression via the TNF-alpha signaling pathway.
abstract: Phosphatidic acid (PA) is implicated in pathophysiological processes associated with cellular signaling events and inflammation, which include the expressional regulation of numerous genes. Here, we show that PA stimulation increases matrix metalloproteinase-9 (MMP-9) expression in macrophages through tumor necrosis factor (TNF)-alpha signaling. We performed antibody array analysis on proteins from macrophages stimulated with PA. PA was found to induce the production of TNF-alpha, but not of TNF receptor (TNFR)1 and TNFR2 in a time-dependent manner and stimulated significant, though delayed, MMP-9 expression. PA induced the phosphorylations of both ERK1/2 and p38, but not of c-jun amino-terminal kinase. Moreover, only ERK1/2 inhibition by U0126 suppressed PA-induced TNF-alpha production and MMP-9 expression. Neutralizing TNF-alpha, TNFR1 or TNFR2 antibodies significantly suppressed PA-induced MMP-9 expression, suggesting that the production of TNF-alpha in response to PA preceded the expression of MMP-9. Moreover, lipopolysaccharide-induced PA also led to TNF-alpha release and resulted in MMP-9 expression. Taken together, these observations suggest that PA may play a role in MMP-9 regulation through ERKs/TNF-alpha/TNFRs-dependent signaling pathway.
authors.affiliation: Department of Biochemistry & Molecular Biology, Aging-Associated Vascular Disease Research Center, Yeungnam University, Daegu 705-717, Republic of Korea.
authors.forename: Jin-Gu
authors.initials: JG
authors.lastname: Lee
authors.forename: Sun-Hye
authors.initials: SH
authors.lastname: Lee
authors.forename: Dae-Weon
authors.initials: DW
authors.lastname: Park
authors.forename: Yoe-Sik
authors.initials: YS
authors.lastname: Bae
authors.forename: Sung-Su
authors.initials: SS
authors.lastname: Yun
authors.forename: Jae-Ryong
authors.initials: JR
authors.lastname: Kim
authors.forename: Suk-Hwan
authors.initials: SH
authors.lastname: Baek
mesh_terms: D000818:Animals; D004789:Enzyme Activation / Q000187:drug effects; D015971:Gene Expression Regulation, Enzymologic / Q000187:drug effects*; D008264:Macrophages / Q000187:drug effects / Q000201:enzymology / Q000378:metabolism; D020780:Matrix Metalloproteinase 9 / Q000378:metabolism*; D051379:Mice; D019950:Mitogen-Activated Protein Kinase 1 / Q000378:metabolism; D048052:Mitogen-Activated Protein Kinase 3 / Q000378:metabolism; D010712:Phosphatidic Acids / Q000494:pharmacology*; D010766:Phosphorylation / Q000187:drug effects; D047888:Receptors, Tumor Necrosis Factor, Type I / Q000378:metabolism; D047889:Receptors, Tumor Necrosis Factor, Type II / Q000378:metabolism; D015398:Signal Transduction / Q000187:drug effects*; D014409:Tumor Necrosis Factor-alpha / Q000378:metabolism*; D048051:p38 Mitogen-Activated Protein Kinases / Q000378:metabolism
chemical_list: D010712:Phosphatidic Acids; D047888:Receptors, Tumor Necrosis Factor, Type I; D047889:Receptors, Tumor Necrosis Factor, Type II; D014409:Tumor Necrosis Factor-alpha; D019950:Mitogen-Activated Protein Kinase 1; D048052:Mitogen-Activated Protein Kinase 3; D048051:p38 Mitogen-Activated Protein Kinases; D020780:Matrix Metalloproteinase 9