Interferon regulatory factors regulate interleukin-1beta-converting enzyme expression and apoptosis in vascular smooth muscle cells.

Published

Journal Article

-Apoptosis has been reported to play a pivotal role in vascular remodeling. However, cellular mechanisms of apoptosis in vascular smooth muscle cells (VSMCs) have not been well defined. In this study, we focused on interleukin-1beta-converting enzyme (ICE), a key protease in the induction of apoptosis in lymphocytes and fibroblasts. We observed an increase in ICE mRNA expression in rat aortic VSMCs after serum depletion, with a peak at 12 hours and then a gradual decline. This was associated with DNA fragmentation, a hallmark of apoptosis and morphological changes of apoptosis. Treatment of these VSMCs with the ICE inhibitor N-(N-acetyl-tyrosinyl-valinyl-alaninyl)-3-amino-4-oxob utanoic acid (YVAD-CHO) attenuated DNA fragmentation. The increased ICE mRNA expression was preceded by an increase in the mRNA expression of interferon regulatory factor (IRF)-1, peaking at 6 hours after serum removal, and a rapid but transient decrease in IRF-2 mRNA expression, reaching a nadir at 3 hours after serum depletion. To demonstrate that these reciprocal changes in IRF-1 and IRF-2 regulated ICE expression and induced apoptosis, we transfected antisense oligonucleotides for IRF-1 and IRF-2 into VSMCs and examined ICE mRNA expression and apoptotic changes. IRF-1 antisense pretreatment attenuated the increase in ICE expression and reduced apoptotic changes, whereas IRF-2 antisense treatment increased ICE mRNA expression and enhanced apoptotic changes. Taken together, our results suggest that serum growth factor depletion in VSMCs upregulates IRF-1 and downregulates IRF-2, thereby increasing ICE expression and inducing apoptosis.

Full Text

Duke Authors

Cited Authors

  • Horiuchi, M; Yamada, H; Akishita, M; Ito, M; Tamura, K; Dzau, VJ

Published Date

  • January 1999

Published In

Volume / Issue

  • 33 / 1

Start / End Page

  • 162 - 166

PubMed ID

  • 9931097

Pubmed Central ID

  • 9931097

International Standard Serial Number (ISSN)

  • 0194-911X

Digital Object Identifier (DOI)

  • 10.1161/01.hyp.33.1.162

Language

  • eng

Conference Location

  • United States