Insights into the transcriptional regulation of the anthracycline reductase AKR7A2 in human cardiomyocytes

Toxicol Lett. 2019 Jun 1:307:11-16. doi: 10.1016/j.toxlet.2019.02.015. Epub 2019 Feb 25.

Abstract

Aldo-Keto Reductase Family 7 Member A2 (AKR7A2) is the most abundant anthracycline metabolizing enzyme in human myocardium. Myocardial AKR7A2 contributes to the synthesis of cardiotoxic C-13 anthracycline alcohol metabolites (e.g., doxorubicinol). The factors that govern the transcription of human AKR7A2 in cardiomyocytes remain largely unexplored. In this study, we performed the functional characterization of the AKR7A2 gene promoter in human AC16 cardiomyocytes. Experiments with gene reporter constructs and chromatin immunoprecipitation assays suggest that NF-κB binds to specific regions in the AKR7A2 promoter. Doxorubicin treatment modified the cellular levels of NF-κB and the expression of AKR7A2. Moreover, doxorubicin treatment led to changes in the pattern of AKR7A2 phosphorylation status. Our results suggest that AKR7A2 expression in human cardiomyocytes is mediated by NF-κB through conserved response elements in the proximal gene promoter region. This study provides the first insights into the functional characteristics of the human AKR7A2 gene promoter.

Keywords: Aldo-Keto Reductase Family 7 Member A2 (AKR7A2); Anthracyclines; Human cardiomyocytes.

MeSH terms

  • Aldehyde Reductase / metabolism*
  • Chromatin Immunoprecipitation
  • Doxorubicin / pharmacology
  • Gene Expression Regulation
  • Humans
  • Myocytes, Cardiac / enzymology
  • Myocytes, Cardiac / metabolism*
  • NF-kappa B / metabolism
  • Phosphorylation
  • Promoter Regions, Genetic

Substances

  • NF-kappa B
  • Doxorubicin
  • aflatoxin B1 aldehyde reductase
  • Aldehyde Reductase