γ-Oryzanol

Kinase experiment:

To assess the inhibitory activity of each compound on DNA methylation, the formation of S-adenosyl-l-homocysteine (SAH) is measured in the presence of each compound (20 μM for screening assays),S-adenosyl methionine (SAM; 10 μM) and DNMT substrate (4 ng/μL) at 37°C for 90 min. To evaluate the Michaelis-Menten kinetics, DNMT1 (20 μM) is incubated with γ-Oryzanol, SAM (5 μM) and the indicated concentration of poly dI-dC at 37°C for 90 min. DNMT3a (100 μM) and DNMT3b (100 μM) are incubated with γ-Oryzanol, SAM (5 μM) and the indicated concentration of poly dG•dC at 37°C for 120 min. The assays are performed in quadruplicate. Extracted protein (0.75 mg/mL) is incubated with SAM (5 μM), poly dI-dC (5 μg/mL), and poly dG•dC (5 μg/mL) at 40°C for 120 min, and SAH formation is measured[1].

Animal experiment:

Mice[1] Seven-week-old male C57BL/6J mice are used. To evaluate the preference for the HFD, γ-Oryzanol is administrated to 8-week-old mice by gavage during the food choice test. For the other experiments, an HFD containing 0.4% γ-Oryzanol is manufactured as pellets. After 12 weeks of feeding, tissue is collected from the striatum and hypothalamus. The daily intake of γ-Oryzanol, estimated from the mean food intake of the mice, is approximately 320 μg/g body weight. The doses of γ-Oryzanol are determined.

References:

[1]. Kozuka C, et al. Impact of brown rice-specific γ-oryzanol on epigenetic modulation of dopamine D2 receptors in brain striatum in high-fat-diet-induced obesity in mice. Diabetologia. 2017 Aug;60(8):1502-1511.