The effect of tissue factor pathway inhibitor on the expression of monocyte chemotactic protein-3 and IκB-α stimulated by tumour necrosis factor-α in cultured vascular smooth muscle cells.

BACKGROUND

In recent years, the importance of inflammation in restenosis has been recognized gradually. When vascular injury occurs, NF-κB, which controls transcription of many inflammatory genes in restenosis (such as monocyte chemotactic protein-3 [MCP-3]), is activated by IκB degradation, leaving the NF-κB dimer-free to translocate to the nucleus to activate specific target genes.

AIMS

To investigate the effect of tissue factor pathway inhibitor (TFPI) on MCP-3 expression and IκB-α degradation stimulated by tumour necrosis factor (TNF)-α in vascular smooth muscle cells (VSMCs), thus further elucidating the mechanism of the inhibitory effect of TFPI on restenosis.

METHODS

Dulbecco's modified Eagle's medium or human recombinant adenoviruses expressing TFPI or bacterial β-galactosidase (LacZ) were used to infect rat aortic VSMCs in vitro. Enzyme-linked immunosorbent assays were used to detect exogenous TFPI expression and reverse transcription-polymerase chain reactions were used to detect MCP-3 expression after TNF-α stimulation in transfected cells. Western blotting and immunofluorescence microscopy were used to examine IκB-α expression.

RESULTS

TFPI protein was detected in the TFPI group after gene transfer. The cells were stimulated with TNF-α for 6 hours on the third day after gene transfer. MCP-3 messenger ribonucleic acid expression was lower in the TFPI group than in the LacZ group (P<0.05) and IκB-α degradation was lower in the TFPI group than in the LacZ group in the cytoplasm (P<0.05).

CONCLUSION

TFPI inhibited MCP-3 expression induced by TNF-α; this effect may be propagated through the NF-κB pathway. TFPI gene transfer may be a new therapeutic strategy for inhibiting restenosis in clinical situations.