%0 Journal Article %A Kelley, Mary J. %A Rose, Anastasia Y. %A Song, Kaili %A Chen, Yanwen %A Bradley, John M. %A Rookhuizen, Derek %A Acott, Ted S. %T Synergism of TNF and IL-1 in the Induction of Matrix Metalloproteinase-3 in Trabecular Meshwork %B Investigative Ophthalmology & Visual Science %D 2007 %R 10.1167/iovs.06-1445 %J Investigative Ophthalmology & Visual Science %V 48 %N 6 %P 2634-2643 %@ 1552-5783 %X purpose. TNF and IL-1 increase matrix metalloproteinase-3 (MMP-3) expression in the trabecular meshwork (TM). TNF-α, in combination with IL-1α or IL-1β, produces highly synergistic MMP-3 increases. Possible mechanisms for this synergism in TM cells were investigated. methods. Porcine and human TM cells were treated with TNF-α, IL-1α, IL-1β and their combinations. Western immunoblots were used to evaluate MMP-3, MMP-9, MMP-12, TNF-α, IL-1α, IL-1β, IL-6, TNF receptor I (RI), IL-1 RI, and IL-1 RII levels and the phosphorylation of Erk, JNK, and p38 MAP kinases. Dose–response effects for TNF-α, IL-1α and IL-1β on MMP-3 were evaluated. Microarray and quantitative RT-PCR were used to determine mRNA levels. MMP-3 transcription rate was assessed by transfecting TM cells with an MMP-3 promoter/reporter construct. Combined cytokine effects on outflow facility were appraised in perfused anterior segment organ culture. results. TNF-α, IL-1α, and IL-1β each individually increased MMP-3 levels, whereas TNF-α in combination with IL-1α or IL-1β produced highly synergistic increases. MMP-9 and MMP-12 levels were also elevated, but only MMP-12 showed synergism. IL-1α, IL-1β, and IL-6, but not TNF-α mRNA or protein level, were elevated by these cytokines. Maximum MMP-3 production for individual cytokines, even at high doses, was far less than with dual cytokine doses. Erk 1 and 2, JNK 1 and 2, and p38 α and β phosphorylation increased, but not synergistically. However, phosphorylation of novel isoforms of JNK and p38 δ and γ did show synergism. MMP-3 mRNA levels and transcription rates also demonstrated synergism. TNF-α significantly increased IL-1 RI levels. Synergism in outflow facility was observed with TNF-α and IL-1α. conclusions. TNF-α, in combination with IL-1α or IL-1β, produced intense synergistic increases in MMP-3 and MMP-12 but not in MMP-9. Induction of IL-1 RI by TNF-α partially explains the synergism. Responses of novel JNK and p38 MAP kinase δ and γ isoforms also partially account for the synergism. Understanding this strong synergistic effect may provide useful insight into optimizing therapeutic regulation of intraocular pressure in glaucoma. %[ 3/3/2021 %U https://doi.org/10.1167/iovs.06-1445