Triptolide suppresses IL-1β-induced chemokine and stromelysin-1 gene expression in human colonic subepithelial myofibroblasts
Abstract
Aim: To examine the inhibitive effects of triptolide on the expression of IL-8,
monocyte chemotactic protein (MCP)-1, and matrix metalloproteinases (MMP)-3
in subepithelial myofibroblasts (SEMF) stimulated with IL-1β. Methods: SEMF
cultures were established from normal colons in patients who underwent gut
resection for colorectal carcinoma. Chemokine and MMP-3 expressions were
determined by ELISA and RT-PCR. The cytosolic amount of phosphorylation of
IκB-α (p-IκB-α) was determined by Western blotting. The DNA binding capacity
of NF-κB was evaluated by electrophoretic mobility shift assays. Results: IL-1β
stimulated protein and mRNA expression of IL-8, MCP-1, and MMP-3 in SEMF.
Triptolide inhibited these effects of IL-1β in a dose-dependent manner. Mechanistic
studies revealed that triptolide markedly decreased IL-1β-induced NF-κB
DNA binding capacity and cytosolic amount of p-IκB-α. These results showed
that triptolide inhibited IL-1β-induced chemokine and MMP-3 expression in SEMF
through the NF-κB pathway. Conclusion: Triptolide inhibited IL-1β-induced
chemokine and MMP-3 expression in SEMF by preventing the phosphorylation
of IκB-α.
Keywords:
monocyte chemotactic protein (MCP)-1, and matrix metalloproteinases (MMP)-3
in subepithelial myofibroblasts (SEMF) stimulated with IL-1β. Methods: SEMF
cultures were established from normal colons in patients who underwent gut
resection for colorectal carcinoma. Chemokine and MMP-3 expressions were
determined by ELISA and RT-PCR. The cytosolic amount of phosphorylation of
IκB-α (p-IκB-α) was determined by Western blotting. The DNA binding capacity
of NF-κB was evaluated by electrophoretic mobility shift assays. Results: IL-1β
stimulated protein and mRNA expression of IL-8, MCP-1, and MMP-3 in SEMF.
Triptolide inhibited these effects of IL-1β in a dose-dependent manner. Mechanistic
studies revealed that triptolide markedly decreased IL-1β-induced NF-κB
DNA binding capacity and cytosolic amount of p-IκB-α. These results showed
that triptolide inhibited IL-1β-induced chemokine and MMP-3 expression in SEMF
through the NF-κB pathway. Conclusion: Triptolide inhibited IL-1β-induced
chemokine and MMP-3 expression in SEMF by preventing the phosphorylation
of IκB-α.