MUTATIONAL SPECIFICITY OF 2, 6-DIMETHYLANILINE WITH IN VITRO HUMAN S9 METABOLIC ACTIVATION IN THE GPT GENE OF AS52 CELLS


Seo Hyun Moon, Min Young Kim

Abstract


Objective: The purpose of the current work was to characterize mechanisms of cytotoxicity and mutagenesis of a potential human bladder carcinogen 2,6-dimethylaniline (2,6-DMA).

Methods: Chinese hamster ovary (CHO) AS52 cells were exposed to either human S9 activated 2,6-DMA for 6 h or its N-hydroxylamine and aminophenol metabolites for 1 h in serum-free medium. Cell survival determined by trypan blue exclusion 24 h after treatment, and 6-thioguanine-resistant mutants at the xanthine-guanine phosphoribosyltransferase (gpt) gene locus were assessed with doses of which relative survival is 30% or more. Nested PCR-based deletion analysis was also performed.

Results: AS52 cells exhibited a dose-dependent increase in cytotoxicity and mutant fraction upon treatment of 2,6-DMA and its metabolites, but showing considerable variation in potency with aminophenol metabolites having the highest potency and parent compound at least; at the highest 2,6-dimethyaminophenol dose (10 μM), the mutant fraction in AS52 cells was 8 fold (13.2×10-5) greater than the spontaneous fraction of 1.62×10-5. Total deletion of the gpt gene sequences was found in 1 (4%) of spontaneous and 2 (6%) of the 6-thioguanine mutants generated by N-hydroxy-2,6-DMA.

Conclusion: These findings indicate the mutagenicity of 2,6-DMA at the gpt gene, which is mediated through hydroxylamine and aminophenol metabolites, and contribute to the elucidation of mechanisms through which 2,6-DMA may exert its effects in vivo.


Keywords


2,6-Dimethylaniline, Metabolic activation, Genotoxicity, AS52/gpt assay

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About this article

Title

MUTATIONAL SPECIFICITY OF 2, 6-DIMETHYLANILINE WITH IN VITRO HUMAN S9 METABOLIC ACTIVATION IN THE GPT GENE OF AS52 CELLS

Keywords

2,6-Dimethylaniline, Metabolic activation, Genotoxicity, AS52/gpt assay

DOI

10.22159/ijpps.2018v10i1.23133

Date

01-01-2018

Additional Links

Manuscript Submission

Journal

International Journal of Pharmacy and Pharmaceutical Sciences
Vol 10, Issue 1, 2018 Page: 19-22

Online ISSN

0975-1491

Statistics

61 Views | 66 Downloads

Authors & Affiliations

Seo Hyun Moon
Department of Forensic DNA, National Forensic Service, Wonju, Gangwon-do, Republic of Korea

Min Young Kim
Toxicology Laboratory, Faculty of Biotechnology (Biomaterials), College of Applied Life Science, SARI, Jeju National University, Jeju, Republic of Korea


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