Interleukin 1 and Prostaglandin E2 Affect Expression of DNA Methyltransferases and Global DNA Methylation Levels in Human Gingival Fibroblasts
Location
Philadelphia
Start Date
3-5-2017 1:00 PM
Description
Objective: To determine the effects of inflammatory cytokines and mediators on expression of DNMT and TET enzymes in human gingival fibroblasts isolated from patients with periodontitis.
Methods: Expression of DNA methyltransferase (DNMT1 and 3a) and demethylase (TET1) was examined by RT-PCR. Protein levels of DNMT3a were determined by ELISA. Global levels of DNA methylation and hydroxymethylation were measured in ELISA-like assays.
Results: Treatment of HGF with IL-1 increased levels of DNMT1 , but decreased in DNMT3a mRNA in the same samples. Global levels of 5mC were increased in HGF treated with IL-1 for 72 hours relative to untreated controls. PGE2 caused a dose-dependent decrease in levels of DNMT3a similar to IL-1, but also decreased levels of DNMT1 and TET1. DNMT3a protein levels were decreased by IL-1 and PGE2 in HGF. Inhibition of IL-1 induced PGE2 production with NS398 partially reversed the inhibitory effects of PGE2 on DNMT3a and TET expression. Use of EP receptor agonists showed that EP4 stimulation resulted in decreased expression of DNMT3a. Global levels of 5hmC were not significantly changed in response to treatment with IL-1 or PGE2.
Conclusion: IL-1 and PGE2 alter expression of DNA methylating and demethylating enzymes, and result in changes in global DNA methylation. Such changes have the potential to alter gene expression patterns over time and could be involved in the predisposition to cancer associated with chronic inflammation. IL-1 inhibition of DNMT3a and TET1 expression in HGF is likely mediated at least in part through increased production of PGE2, which exerts its inhibitory activity through the EP4 receptor.
Interleukin 1 and Prostaglandin E2 Affect Expression of DNA Methyltransferases and Global DNA Methylation Levels in Human Gingival Fibroblasts
Philadelphia
Objective: To determine the effects of inflammatory cytokines and mediators on expression of DNMT and TET enzymes in human gingival fibroblasts isolated from patients with periodontitis.
Methods: Expression of DNA methyltransferase (DNMT1 and 3a) and demethylase (TET1) was examined by RT-PCR. Protein levels of DNMT3a were determined by ELISA. Global levels of DNA methylation and hydroxymethylation were measured in ELISA-like assays.
Results: Treatment of HGF with IL-1 increased levels of DNMT1 , but decreased in DNMT3a mRNA in the same samples. Global levels of 5mC were increased in HGF treated with IL-1 for 72 hours relative to untreated controls. PGE2 caused a dose-dependent decrease in levels of DNMT3a similar to IL-1, but also decreased levels of DNMT1 and TET1. DNMT3a protein levels were decreased by IL-1 and PGE2 in HGF. Inhibition of IL-1 induced PGE2 production with NS398 partially reversed the inhibitory effects of PGE2 on DNMT3a and TET expression. Use of EP receptor agonists showed that EP4 stimulation resulted in decreased expression of DNMT3a. Global levels of 5hmC were not significantly changed in response to treatment with IL-1 or PGE2.
Conclusion: IL-1 and PGE2 alter expression of DNA methylating and demethylating enzymes, and result in changes in global DNA methylation. Such changes have the potential to alter gene expression patterns over time and could be involved in the predisposition to cancer associated with chronic inflammation. IL-1 inhibition of DNMT3a and TET1 expression in HGF is likely mediated at least in part through increased production of PGE2, which exerts its inhibitory activity through the EP4 receptor.