Figure 1.

Inhibitory effects of rice bran and vitamin B6 on hypoxia-inducible factor (HIF) activity. (A) A process of drug screenings for HIF inhibitors. After the first screening, 10 samples were shown to be positive. After the second screening, four food ingredients (lactoferrin, rice bran, panax ginseng and Garcinia cambogia) with their expected 2 component compounds (hydroxycitric acid and vitamin B6) were selected as HIF inhibitors. (B) Quantitative analyses of HIF-reporter luciferase assay using ARPE-19 cells (n = 3 per group) showed that rice bran (1 mg/mL) and vitamin B6 (1 mg/mL) inhibited HIF activity induced by 200 µM CoCl₂. *** p < 0.001, ### p < 0.001, compared with no treatment and 200 µM of CoCl₂ treatment, respectively. Bar graphs were presented as mean with the ± standard deviation. The data were analyzed using one-way ANOVA followed by a Bonferroni post hoc test. Solvents, rice bran: DMSO; vitamin B6: water.