γ-Tocotrienol upregulates aryl hydrocarbon receptor expression and enhances the anticancer effect of baicalein

Biochem Biophys Res Commun. 2016 May 13;473(4):801-807. doi: 10.1016/j.bbrc.2016.03.111. Epub 2016 Apr 4.

Abstract

Previous studies have identified biomolecules that mediate the physiological actions of food factors, such as amino acids, vitamins, fatty acids, minerals, plant polyphenols, and lactobacilli, suggesting that our bodies are equipped with an innate system that senses which food factors are required to maintain our health. However, the effects of environmental factors on food factor sensing (FFS) remains largely unknown. Tocotorienols (T3s), which belongs to the vitamin E family, possess several physiological functions, including cholesterol lowering and neuroprotective effects. Here, we investigated the effects of naturally abundant γ-T3 on FFS-related gene expressions in melanoma using a DNA chip. Our results showed that γ-T3 increased the expression level of aryl hydrocarbon receptor (AhR), a sensing molecule to plant polyphenol baicalein. The co-treatment with γ-T3 and baicalein enhanced the anti-proliferative activity of baicalein, accompanied by the downstream events of AhR-activation induced by baicalein. These data suggest that γ-T3 upregulates AhR expression and enhances its sensitivity to baicalein.

Keywords: Aryl hydrocarbon receptor; Baicalein; Food factor sensing; Tocotrienol.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Antineoplastic Combined Chemotherapy Protocols / pharmacology*
  • Antineoplastic Combined Chemotherapy Protocols / therapeutic use
  • Apoptosis / drug effects
  • Cell Line, Tumor
  • Cell Proliferation / drug effects
  • Chromans / pharmacology*
  • Chromans / therapeutic use
  • Dose-Response Relationship, Drug
  • Drug Synergism
  • Flavanones / pharmacology*
  • Flavanones / therapeutic use
  • Melanoma, Experimental / drug therapy
  • Melanoma, Experimental / metabolism*
  • Melanoma, Experimental / pathology
  • Mice
  • Receptors, Aryl Hydrocarbon / metabolism*
  • Up-Regulation / drug effects*
  • Vitamin E / analogs & derivatives*
  • Vitamin E / pharmacology
  • Vitamin E / therapeutic use

Substances

  • Chromans
  • Flavanones
  • Receptors, Aryl Hydrocarbon
  • Vitamin E
  • plastochromanol 8
  • baicalein