title: Role of p38 MAPK on the down-regulation of matrix metalloproteinase-9 expression in rat astrocytes.
abstract: In spite of their pathophysiological importance in neuro-inflammatory diseases, little is known about the signal transduction pathways that lead to the induction of matrix metalloproteinases (MMPs) in the central nervous system. We reported previously that lipopolysaccharide (LPS) induced MMP-9 expression through ERK1/2 pathway in rat primary astrocytes (Glia 41:15-24, 2003). Here, we investigated the role of other MAPK pathways, including p38 and JNK/SAPK, on the regulation of MMP-9 expression in LPS-stimulated rat primary astrocytes. LPS activated both p38 and JNK in astrocytes. Treatment with a specific p38 MAPK inhibitor SB203580, but not JNK inhibitor SP600125, increased the LPS-stimulated MMP-9 expression in a concentration-dependent manner. Anti-inflammatory cytokines, including IFN-gamma and IL-4, activated p38 MAPK and decreased MMP-9 production in LPS-stimulated astrocytes. When p38 MAPK activation was blocked by SB203580, the inhibitory effects of these cytokines on MMP-9 induction were abolished. Finally, direct injection of SB203580 into the lateral ventricle of rat brain increased the LPS-induced MMP-9 activity in cerebral cortex. Altogether, these results suggest that p38 activation down-regulates the inflammatory stimulation-induced overexpression of MMP-9, both in primary astrocytes and in cerebral cortex. The elaborate interplay between ERK1/2 and p38 pathways provides a more sophisticated mechanism for regulating MMP-9 activity in neuroinflammatory diseases.
authors.affiliation: Department of Pharmacology, College of Pharmacy, Seoul National University, Seoul, Korea.
authors.forename: Chan Young
authors.initials: CY
authors.lastname: Shin
authors.forename: Woo Jong
authors.initials: WJ
authors.lastname: Lee
authors.forename: Ji Woong
authors.initials: JW
authors.lastname: Choi
authors.forename: Min Sik
authors.initials: MS
authors.lastname: Choi
authors.forename: Gyu Hwan
authors.initials: GH
authors.lastname: Park
authors.forename: Byoung Kwon
authors.initials: BK
authors.lastname: Yoo
authors.forename: Sun Young
authors.initials: SY
authors.lastname: Han
authors.forename: Jae Ryun
authors.initials: JR
authors.lastname: Ryu
authors.forename: Eui Yul
authors.initials: EY
authors.lastname: Choi
authors.forename: Kwang Ho
authors.initials: KH
authors.lastname: Ko
mesh_terms: D000818:Animals; D001253:Astrocytes / Q000201:enzymology*; D015536:Down-Regulation; D015971:Gene Expression Regulation, Enzymologic; D007093:Imidazoles / Q000494:pharmacology; D007371:Interferon-gamma / Q000494:pharmacology; D015847:Interleukin-4 / Q000494:pharmacology; D008070:Lipopolysaccharides / Q000494:pharmacology; D020935:MAP Kinase Signaling System; D020780:Matrix Metalloproteinase 9 / Q000235:genetics*; D011725:Pyridines / Q000494:pharmacology; D051381:Rats; D017207:Rats, Sprague-Dawley; D048051:p38 Mitogen-Activated Protein Kinases / Q000502:physiology*
chemical_list: D007093:Imidazoles; D008070:Lipopolysaccharides; D011725:Pyridines; D015847:Interleukin-4; D007371:Interferon-gamma; D048051:p38 Mitogen-Activated Protein Kinases; D020780:Matrix Metalloproteinase 9; C093642:SB 203580