Catechins inhibit vascular endothelial growth factor production and cyclooxygenase-2 expression in human dental pulp cells.

ABSTRACT

AIM: To investigate the effect of catechins on vascular endothelial growth factor (VEGF) production and cyclooxygenase-2 (COX-2) expression in human dental pulp cells (HDPC) stimulated with bacteria-derived factors or pro-inflammatory cytokines. METHODOLOGY: Morphologically fibroblastic cells established from explant cultures of healthy human dental pulp tissues were used as HDPC. HDPC pre-treated with catechins, epigallocatechin-3-gallate (EGCG) or epicatechin gallate (ECG), were exposed to lipopolysaccharide (LPS), peptidoglycan (PG), interlukin-1ß (IL-1ß) or tumour necrosis factor-α (TNF-α). VEGF production was examined by enzyme-linked immunosorbent assay, and COX-2 expression was assessed by immunoblot. RESULTS: EGCG and ECG significantly reduced LPS- or PG-mediated VEGF production in the HDPC in a dose-dependent manner. EGCG also prevented IL-1ß-mediated VEGF production. Although TNF-α did not enhance VEGF production in the dental pulp cells, treatment of 20 µg mL(-1) of EGCG decreased the level of VEGF. In addition, the catechins attenuated COX-2 expression induced by LPS and IL-1ß. CONCLUSIONS: The up-regulated VEGF and COX-2 expressions in the HDPC stimulated with these bacteria-derived factors or IL-1ß were diminished by the treatment of EGCG and ECG. These findings suggest that the catechins may be beneficial as an anti-inflammatory tool of the treatment for pulpal inflammation.