Mechanism of carbon monoxide affecting the expression of cellular adhesion molecule under stimulation of inflammatory cytokines to human gingival fibroblasts / 华西口腔医学杂志

ABSTRACT

<p><b>OBJECTIVE</b>To investigate the mechanism by which carbon monoxide inhibits the expression of adhesion molecules on human gingival fibroblasts (HGF) stimulated with inflammatory cytokines.</p><p><b>METHODS</b>HGF were cultured in vitro, and stimulated with 50 ng x mL tumor necrosis factor-alpha (TNF-alpha) and 10 ng x mL(-1) interleukin-1beta (IL-1beta) concurrently in the presence or absence of carbon monoxide releasing molecule-3 (CORM-3) at 500 micromol x L-1. Expression of phosphorylated extracellular regulated protein kinase (ERK), phosphorylated c-Jun N-terminal kinase (NK) and phosphorylated p38 in mitogen-activated protein kinase(MAPK) pathway was studied by Western blot at 10 min and 20 min, respectively. Nuclear expression of nuclear factor-kappaB (NF-kappaB) was checked by Western blot after 4 h stimulation. In some experiments, cells were prestimulated by 1H-[1,2,4]oxadiazolo[4,3-alpha]quinoxalin-1-one (ODQ) for 8 h before cytokine stimulation and the expression of intercellular adhesion molecule-1 (ICAM-1) was checked by Western blot after 24 h.</p><p><b>RESULTS</b>CORM-3 significantly inhibited the phosphorylation of MAPK p38 after 10 min stimulation with cytokines, but had no signifi-cant effect on the phosphorylation of ERK and JNK. CORM-3 significantly inhibited the nuclear expression of NF-KB-p65 on HGF after 4 h stimulation by inflammatory cytokines. The inhibitory effect of CORM-3 on the expression of ICAM-1 was not influenced by guanylate cyclase inhibitor ODQ.</p><p><b>CONCLUSION</b>The inhibitory effect of carbon monoxide on the expression of adhesion molecules might be exerted by its inhibitory effect on the NF-kappaB activity and MAPK p38 phosphorylation.</p>