Transcriptional regulation of inflammatory mediators secreted by human colonic circular smooth muscle cells

We investigated the transcriptional regulation of secretion of pro- and anti-inflammatory mediators by human colonie circular smooth muscle cells (HCCSMC) in response to tumor necrosis factor (TNF)-α. Gene chip array analysis indicated that HCCSMC express a specific panel of 11 cytokines, chemokines, and cell adhesion molecules in a time-dependent manner in response to TNF-α. The chip array data were supported by quantitative analysis of mRNA and protein expressions of interleukin (IL)-6, IL-8, intercellular adhesion molecule (ICAM)-1 and IL-11. The proinflammatory mediators were expressed early, whereas the anti-inflammatory cytokine IL-11 was expressed late after TNF-α treatment. The expression of ICAM-1 on HCCSMC increased lymphocyte adhesion to these cells, which was blocked by pretreatment with antibody to ICAM-1. TNF-α acted on both R₁ and R₂ receptors to induce the expression of ICAM-1. Pretreatment of HCCSMC with antisense oligonucleotides to p65 nuclear factor-κB (NF-κB) blocked the expression of ICAM-1, whereas pretreatment with antisense oligonucleotides to p50 NF-κB had little effect. The overexpression of p65 NF-κB enhanced the constitutive expression of ICAM-1, and TNF-α treatment had no further effect. The delayed expression of endogenous IL-11 limited the expression of ICAM-1, and pretreatment of HCCSMC with antisense oligonucleotides to IL-11 enhanced it. We conclude that TNF-α induces gene expression in HCCSMC for programmed synthesis and release of pro- and anti-inflammatory mediators.