The AAPS Journal

, Volume 16, Issue 4, pp 727–735 | Cite as

Apigenin Reactivates Nrf2 Anti-oxidative Stress Signaling in Mouse Skin Epidermal JB6 P + Cells Through Epigenetics Modifications

  • Ximena Paredes-Gonzalez
  • Francisco Fuentes
  • Zheng-Yuan Su
  • Ah-Ng Tony Kong
Research Article Theme: Natural Products Drug Discovery in Cancer Prevention


Nrf2 is a crucial transcription factor that controls a critical anti-oxidative stress defense system and is implicated in skin homeostasis. Apigenin (API), a potent cancer chemopreventive agent, protects against skin carcinogenesis and elicits multiple molecular signaling pathways. However, the potential epigenetic effect of API in skin cancer chemoprotection is not known. In this study, bisulfite genomic DNA sequencing and methylated DNA immunoprecipitation were utilized to investigate the demethylation effect of API at 15 CpG sites in the Nrf2 promoter in mouse skin epidermal JB6 P + cells. In addition, qPCR and Western blot analyses were performed to evaluate the mRNA and protein expression of Nrf2 and the Nrf2 ARE downstream gene, NQO1. Finally, the protein expression levels of DNA methyltransferases (DNMTs) and histone deacetylases (HDACs) were evaluated using API and the DNMT/HDAC inhibitor 5-aza/ trichostatin A. Our results showed that API effectively reversed the hypermethylated status of the 15 CpG sites in the Nrf2 promoter in a dose-dependent manner. API enhanced the nuclear translocation of Nrf2 and increased the mRNA and protein expression of Nrf2 and the Nrf2 downstream target gene, NQO1. Furthermore, API reduced the expression of the DNMT1, DNMT3a, and DNMT3b epigenetic proteins as well as the expression of some HDACs (1–8). Taken together, our results showed that API can restore the silenced status of Nrf2 in skin epidermal JB6 P + cells by CpG demethylation coupled with attenuated DNMT and HDAC activity. These results may provide new therapeutic insights into the prevention of skin cancer by dietary phytochemicals.


apigenin DNMTs epigenetics HDACs JB6 P+ Nrf2 skin cancer 



We thank all the members in Dr. Ah-Ng Tony Kong’s lab for their helpful discussion and preparation of this manuscript. This work was supported by institutional funds.

Conflict of interest

No potential conflicts of interest were disclosed.


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Copyright information

© American Association of Pharmaceutical Scientists 2014

Authors and Affiliations

  • Ximena Paredes-Gonzalez
    • 1
  • Francisco Fuentes
    • 1
  • Zheng-Yuan Su
    • 1
  • Ah-Ng Tony Kong
    • 1
  1. 1.Department of Pharmaceutics, Ernest Mario School of Pharmacy, RutgersThe State University of New JerseyPiscatawayUSA

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