Biochemical and Biophysical Research Communications, Vol.473, No.4, 801-807, 2016
gamma-Tocotrienol upregulates aryl hydrocarbon receptor expression and enhances the anticancer effect of baicalein
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 gamma-T3 on FFS-related gene expressions in melanoma using a DNA chip. Our results showed that gamma-T3 increased the expression level of aryl hydrocarbon receptor (AhR), a sensing molecule to plant polyphenol baicalein. The co-treatment with gamma-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 gamma-T3 upregulates AhR expression and enhances its sensitivity to baicalein. (C) 2016 Elsevier Inc. All rights reserved.