title: Inhibitory mechanism of MMP-9 gene expression by ethyl pyruvate in lipopolysaccharide-stimulated BV2 microglial cells.
abstract: Ethyl pyruvate (EP) is a stable derivative of pyruvate and has been identified as a therapeutic agent for various inflammatory diseases. In the present study, we showed that EP and sodium pyruvate (SP) inhibited the production of TNF-α, nitric oxide (NO), or reactive oxygen species (ROS) in LPS-stimulated BV2 microglial cells. The inhibitory effects of EP were more potent than SP. Because matrix metalloproteinase-9 (MMP-9) plays a key role in neuroinflammation, as well as in neuronal cell death, we examined the effect of EP on MMP-9 expression. RT-PCR and Western blot analyses revealed that EP inhibits MMP-9 expression at mRNA and protein levels in LPS-stimulated BV2 cells. In addition, EP suppressed MMP-9 secretion, as demonstrated by gelatin zymography analysis. In contrast, SP did not affect MMP-9 expression at an equivalent concentration of EP. Further mechanistic studies revealed that EP inhibits MMP-9 promoter activity by reducing the binding of NF-κB and AP-1 to its cognitive binding sites. In addition, EP suppressed LPS-induced phosphorylation of p38 MAPK, ERK, and Akt, which are upstream signaling molecules in MMP-9 gene expression. Taken together, our data suggest that the inhibition of MMP-9 may be one of the factors contributing to anti-inflammatory activity of EP in LPS-stimulated microglia.
authors.affiliation: Department of Molecular Medicine, Tissue Injury Defense Research Center, Ewha Womans University Medical School, Seoul, South Korea.
authors.forename: Eun-Jung
authors.initials: EJ
authors.lastname: Lee
authors.forename: Hee-Sun
authors.initials: HS
authors.lastname: Kim
mesh_terms: D000818:Animals; D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000494:pharmacology; D002461:Cell Line, Transformed; D015971:Gene Expression Regulation, Enzymologic / Q000187:drug effects* / Q000502:physiology; D018836:Inflammation Mediators / Q000494:pharmacology*; D008070:Lipopolysaccharides / Q000494:pharmacology; D020780:Matrix Metalloproteinase 9 / Q000235:genetics* / Q000378:metabolism; D061965:Matrix Metalloproteinase Inhibitors; D051379:Mice; D017628:Microglia / Q000187:drug effects* / Q000201:enzymology / Q000473:pathology*; D011480:Protease Inhibitors / Q000494:pharmacology*; D011773:Pyruvates / Q000494:pharmacology*; D012333:RNA, Messenger / Q000037:antagonists & inhibitors / Q000378:metabolism
chemical_list: D000894:Anti-Inflammatory Agents, Non-Steroidal; D018836:Inflammation Mediators; D008070:Lipopolysaccharides; D061965:Matrix Metalloproteinase Inhibitors; D011480:Protease Inhibitors; D011773:Pyruvates; D012333:RNA, Messenger; C046522:ethyl pyruvate; D020780:Matrix Metalloproteinase 9