Dual regulation of tumor necrosis factor-alpha-induced CCL2/monocyte chemoattractant protein-1 expression in vascular smooth muscle cells by nuclear factor-kappaB and activator protein-1: modulation by type III phosphodiesterase inhibition

J Pharmacol Exp Ther. 2004 Jun;309(3):978-86. doi: 10.1124/jpet.103.062620. Epub 2004 Feb 20.

Abstract

Monocyte/macrophage infiltration to the subendothelial space of arterial wall is a critical initial step in atherogenesis, in which CC chemokine ligand 2 (CCL2)/monocyte chemoattractant protein-1 (MCP-1) is thought to play a key role. This study investigated the effectiveness of phosphodiesterase inhibitors, including the nonselective pentoxifylline (PTX) and the selective type III (cilostamide) and type IV (denbufylline) inhibitors, on cytokine-induced CCL2/MCP-1 production in cultured rat vascular smooth muscle cells (VSMCs), and the signal transduction mechanisms whereby they act. Our results showed that tumor necrosis factor (TNF)-alpha induced a marked increase in CCL2/MCP-1 production in dose- and time-dependent manners. 2-(2-Amino-3-methoxyphenyl)-4H-1-benzopyran-4-one (PD98059), 1,4-diamino-2,3-dicyano-1,4-bis(2-aminophenylthio) butadiene (U0126) [both inhibitors of p42/44 mitogen-activated protein kinase (MAPK) kinase], and anthra[1hyphen]9-cd]pyrazol-6(2H)-one (SP600125) [an inhibitor of c-Jun NH(2)-terminal kinases (JNKs)] attenuated TNF-alpha-induced CCL2/MCP-1 production, without affecting I-kappaBalpha degradation or p65/nuclear factor-kappaB (NF-kappaB) nuclear translocation. PD98059 abolished TNF-alpha-activated p42/44 MAPK phosphorylation and c-Fos up-regulation, whereas SP600125 inhibited TNF-alpha-activated JNK and c-Jun phosphorylation. The NF-kappaB inhibitor carbobenzoxy-l-leucyl-l-leucyl-l-leucinal (MG132) attenuated TNF-alpha-induced CCL2/MCP-1 production in the presence of increased phospho-JNK and phospho-c-Jun levels. When SP600125 was added simultaneously, MG132 completely inhibited TNF-alpha-induced CCL2/MCP-1 production. Finally, the pretreatment of VSMCs with PTX or cilostamide, but not denbufylline, reduced TNF-alpha-induced CCL2/MCP-1 production, which was preceded by attenuation of p65/NF-kappaB nuclear translocation, p42/44 MAPK, and JNK-c-Jun phosphorylation, and c-Fos up-regulation. These data indicate that TNF-alpha-stimulated CCL2/MCP-1 production in rat VSMCs is dually regulated by activator protein-1 (AP-1) and NF-kappaB pathways, and inhibition of type III phosphodiesterase contributes substantially to the suppressive effect of PTX on CCL2/MCP-1 production via down-regulation of AP-1 and NF-kappaB signals.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • 3',5'-Cyclic-AMP Phosphodiesterases / antagonists & inhibitors
  • 3',5'-Cyclic-AMP Phosphodiesterases / metabolism*
  • Animals
  • Cells, Cultured
  • Chemokine CCL2 / genetics
  • Chemokine CCL2 / metabolism*
  • Cyclic Nucleotide Phosphodiesterases, Type 3
  • Gene Expression / drug effects
  • Male
  • Mitogen-Activated Protein Kinases / metabolism
  • Muscle, Smooth, Vascular / metabolism
  • NF-kappa B / physiology*
  • Phosphodiesterase Inhibitors / pharmacology
  • Proteins / genetics
  • Proteins / metabolism*
  • RNA, Messenger / drug effects
  • RNA, Messenger / metabolism
  • Rats
  • Rats, Sprague-Dawley
  • Transcription Factor AP-1 / physiology*
  • Tumor Necrosis Factor-alpha / genetics
  • Tumor Necrosis Factor-alpha / metabolism*

Substances

  • Ccl2 protein, rat
  • Chemokine CCL2
  • NF-kappa B
  • Phosphodiesterase Inhibitors
  • Proteins
  • RNA, Messenger
  • Transcription Factor AP-1
  • Tumor Necrosis Factor-alpha
  • Mitogen-Activated Protein Kinases
  • 3',5'-Cyclic-AMP Phosphodiesterases
  • Cyclic Nucleotide Phosphodiesterases, Type 3