Influence of TEGDMA on the expression of pp38 MAPK

Objectives:

Triethylene glycol dimethacrylate (TEGDMA) is a genotoxic monomer of dental resins that caused cell cycle arrest and apoptosis in oral cells. The aim of this study was to investigate the influence of TEGDMA on the stress responsive protein phospho-p38 in the human monocyte cell line THP-1.

Methods:

Monocytes were exposed to TEGDMA (1 and 3 mmol/l) for 0-60 minutes as well as 2, 24, and 48 hours. The expression of phospho-p38 in THP-1 was detected by staining with a specific antibody and quantitated by flow cytometry (FACS). LPS from E. coli (25µg/ml) was used as a positive control for pp38 induction. The data were statistically analyzed (Mann-Whitney-U test).

Results:

TEGDMA increased the expression of phospho-p38 about 14 percent (p= 0,029) after a 30 min exposure period, whereas it was decreased to 68 percent (p=0,029) related to untreated controls after 60 min. Expression of phospho-p38 was also increased after 24 and 48 hours by 86 and 50 percent in the presence of 1 mmol/l TEGDMA and by 118 and 113% by 3 mmol/l TEGDMA. In contrast, stimulation with LPS resulted to a significant increase after 40, 50 and 120 min but not after 24 and 48 hours.

Conclusion:

These results indicate that TEGDMA influences intracellular signalling pathways mediated by the p38 MAPK after long exposure periods. Supported by the Deutsche Forschungsgemeinschaft (Schw 431/11-1).