This Article Full Text Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Kohyama, T. Articles by Rennard, S. I. Search for Related Content PubMed PubMed Citation Articles by Kohyama, T. Articles by Rennard, S. I.

Phosphodiesterase 4 Inhibitor Cilomilast Inhibits Fibroblast-Mediated Collagen Gel Degradation Induced by Tumor Necrosis Factor- and Neutrophil Elastase

Department of Respiratory Medicine, University of Tokyo, Tokyo, Japan; University of Nebraska Medical Center, Omaha, Nebraska; Department of Respiratory Diseases, Jincheng Hospital, Lanzhou, China; and Mount Sinai Hospital, Toronto, Ontario, Canada

Address correspondence to: Stephen I. Rennard, M.D., Pulmonary and Critical Care Medicine, University of Nebraska Medical Center, 985125 Nebraska Medical Center, Omaha, NE 68198-5125. E-mail: srennard{at}unmc.edu

Tissue destruction, resulting in emphysema, can be a consequence of several pathologic processes. The current study evaluated the effects of the phosphodiesterase (PDE)4 inhibitor, cilomilast, and other PDE inhibitors on the ability of fibroblasts to degrade extracellular matrix. Using the three-dimensional collagen gel culture system, fibroblasts (HFL-1) were cultured with tumor necrosis factor (TNF)-, known to induce matrix metalloproteinase (MMP) release, and/or neutrophil elastase (NE), which can induce MMP activation. On Day 4, gels containing TNF- and NE were significantly degraded (20.8 ± 2.9% of original collagen content). Cilomilast (10 µM) inhibited this degradation (84.4 ± 8.4%). Amrinone, a PDE3 inhibitor, and zaprinast, a PDE5 inhibitor, had no effect. Gelatin zymography and immunoblotting revealed that fibroblasts cultured with TNF- released increased amounts of latent MMP-1 and -9. The addition of NE resulted in the conversion of MMP-1 and -9 to their active forms, indicative of collagen degradation. Cilomilast inhibited the release of MMP-1 and -9, as well as conversion of MMP-1 to its active form. Using real-time PCR analysis, cilomilast's effect on MMP-1 release was not associated with the proteinase's mRNA expression, suggesting that the inhibition of release is regulated at the post-transcriptional level. These results suggest that cilomilast may be a potentially effective therapeutic agent in diseases characterized by excessive tissue destruction, such as emphysema.

Abbreviations: Dulbecco's modified Eagle's medium, DMEM • extracellular matrix, ECM • enzyme-linked immunosorbent assay, ELISA • fetal calf serum, FCS • human fetal lung fibroblasts, HFL-1 • horseradish peroxidase, HRP • matrix metalloprotease, MMP • neutrophil elastase, NE • polyacrylamide gel electrophoresis, PAGE • phosphate-buffered saline, PBS • polymerase chain reaction, PCR • phosphodiesterase, PDE • reverse transcription, RT • rat tail tendon collagen, RTTC • sodium dodecyl sulfate, SDS • tissue inhibitor of metalloprotease, TIMP • tumor necrosis factor-, TNF-

This article has been cited by other articles:

				S. Togo, X. Liu, X. Wang, H. Sugiura, K. Kamio, S. Kawasaki, T. Kobayashi, R. F. Ertl, Y. Ahn, O. Holz, et al. PDE4 inhibitors roflumilast and rolipram augment PGE2 inhibition of TGF-{beta}1-stimulated fibroblasts Am J Physiol Lung Cell Mol Physiol, June 1, 2009; 296(6): L959 - L969. [Abstract] [Full Text] [PDF]

				P. A. Martorana, R. Beume, M. Lucattelli, L. Wollin, and G. Lungarella Roflumilast Fully Prevents Emphysema in Mice Chronically Exposed to Cigarette Smoke Am. J. Respir. Crit. Care Med., October 1, 2005; 172(7): 848 - 853. [Abstract] [Full Text] [PDF]

				S. Oger, C. Mehats, E. Dallot, D. Cabrol, and M.-J. Leroy Evidence for a Role of Phosphodiesterase 4 in Lipopolysaccharide-Stimulated Prostaglandin E2 Production and Matrix Metalloproteinase-9 Activity in Human Amniochorionic Membranes J. Immunol., June 15, 2005; 174(12): 8082 - 8089. [Abstract] [Full Text] [PDF]