DNA methylation analysis in rat kidney epithelial cells exposed to 3-MCPD and glycidol


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Senyildiz M., Alpertunga B. , Ozden S.

DRUG AND CHEMICAL TOXICOLOGY, vol.40, no.4, pp.432-439, 2017 (Journal Indexed in SCI) identifier identifier identifier

  • Publication Type: Article / Article
  • Volume: 40 Issue: 4
  • Publication Date: 2017
  • Doi Number: 10.1080/01480545.2016.1255951
  • Journal Name: DRUG AND CHEMICAL TOXICOLOGY
  • Journal Indexes: Science Citation Index Expanded, Scopus
  • Page Numbers: pp.432-439

Abstract

3-Monochloropropane-1,2-diol (3-MCPD) is a well-known food processing contaminant that has
been regarded as a rat carcinogen, which is known to induce Leydig-cell and mammary gland
tumors in males, as well as kidney tumors in both genders. 3-MCPD is highly suspected to be a
non-genotoxic carcinogen. 2,3-Epoxy-1-propanol (glycidol) can be formed via dehalogenation
from 3-MCPD. We aimed to investigate the cytotoxic effects of 3-MCPD and glycidol, then to
demonstrate the possible epigenetic mechanisms with global and gene-specific DNA
methylation in rat kidney epithelial cells (NRK-52E). IC50 value of 3-MCPD was determined as
48mM and 41.39 mM, whereas IC50 value of glycidol was 1.67mM and 1.13mM by MTT and
NRU test, respectively. Decreased global DNA methylation at the concentrations of 100 mM and
1000 mM for 3-MCPD and 100 mM and 500 mM for glycidol were observed after 48 h exposure by
using 5-methylcytosine (5-mC) ELISA kit. Methylation changes were detected in promoter
regions of c-myc and Rassf1a in 3-MCPD and glycidol treated NRK-52E cells by using
methylation-specific PCR (MSP), whereas changes on gene expression of c-myc and Rassf1a
were observed by using real-time PCR. However, e-cadherin, p16, VHL and p15 genes were
unmethylated in their CpG promoter regions in response to treatment with 3-MCPD and
glycidol. Alterations in DNA methylation might be key events in the toxicity of 3-MCPD
and glycidol.

3-Monochloropropane-1,2-diol (3-MCPD) is a well-known food processing contaminant that has been regarded as a rat carcinogen, which is known to induce Leydig-cell and mammary gland tumors in males, as well as kidney tumors in both genders. 3-MCPD is highly suspected to be a non-genotoxic carcinogen. 2,3-Epoxy-1-propanol (glycidol) can be formed via dehalogenation from 3-MCPD. We aimed to investigate the cytotoxic effects of 3-MCPD and glycidol, then to demonstrate the possible epigenetic mechanisms with global and gene-specific DNA methylation in rat kidney epithelial cells (NRK-52E). IC50 value of 3-MCPD was determined as 48mM and 41.39 mM, whereas IC50 value of glycidol was 1.67mM and 1.13mM by MTT and NRU test, respectively. Decreased global DNA methylation at the concentrations of 100 mM and 1000 mu M for 3-MCPD and 100 mu M and 500 mu M for glycidol were observed after 48 h exposure by using 5-methylcytosine (5-mC) ELISA kit. Methylation changes were detected in promoter regions of c-myc and Rassf1a in 3-MCPD and glycidol treated NRK-52E cells by using methylation-specific PCR (MSP), whereas changes on gene expression of c-myc and Rassf1a were observed by using real-time PCR. However, e-cadherin, p16, VHL and p15 genes were unmethylated in their CpG promoter regions in response to treatment with 3-MCPD and glycidol. Alterations in DNA methylation might be key events in the toxicity of 3-MCPD and glycidol. Alterations in DNA methylation might be key events in the toxicity of 3-MCPD and glycidol.