This study examined extracts from five different kinds of lees and nuruk and their organic solvent fractions in terms of several biological functions, such as anti-adipogenic, anti-inflammatory, and anti-proliferative activities. The anti-adipogenic activity was investigated by treating mouse pre-adipocyte 3T3-L1 cells with one extract (YE) and four organic solvent fractions (YAc, PAc, RAc, and WPAc) during adipogenesis. Among the treated samples, the ethyl acetate fraction of W-Ju lees (WPAc) showed the strongest anti-adipogenic effect, which was confirmed with oil red O staining and down-regulation of pro-adipogenic genes such as PPAR-gamma and SCD-1. Treatment with WPAc also reduced the expression of PPAR-gamma in a time-dependent manner. The effects of five different extracts were examined on nitric oxide (NO) production in mouse RAW 264.7 cells to determine anti-inflammatory activity. The ethyl acetate fraction of B-Ju lees (PAc) significantly decreased NO production in LPS-stimulated RAW 264.7 cells and it also inhibited NO production in a dose-dependent manner. The PAc fraction also dramatically decreased the viability of human colorectal cancer HCT116 cells in a dose-dependent manner. In addition, PAc increased the expression of NAG-1 and ATF3 genes in a dose dependent manner. Overall, these results indicate that lees and nuruk have several biological functions, including anti-adipogenic, anti-inflammatory, and anti-proliferative activities.

To investigate whether phytochemicals affect cancer cell viability, human colorectal HCT116 cells were treated with four different phytochemicals. Among these phytochemicals, curcumin is the strongest inhibitor of cell proliferation. In addition, it decreased cell viability in a dose-dependent manner. To unveil the molecular mechanisms involved in the inhibition of cell proliferation by curcumin, we carried out oligo DNA microarray analysis. We found that 137 genes were up-regulated more than 2-fold, and 141 genes were down-regulated more than 2-fold by 25 μM curcumin treatment. Among the up-regulated genes, we selected 3 genes (ATF-3, GADD45A, and NR4A1) to confirm microarray data. The results of RT-PCR strongly agreed with those of the microarray data. Among the phytochemicals used in this study, curcumin is the strongest inducer of ATF3 expression, and increased ATF3 expression in a dose-dependent manner. Interestingly, FACS analysis showed that the inhibition of cell growth by curcumin was recovered by ATF3-siRNA transfection. Finally, we detected the changes of gene expression by ectopic expression of ATF3. The results indicated that many up-regulated genes were related to apoptosis. Overall, these results suggest that ATF3 may play an important role in the anti-proliferative activity of curcumin in human colorectal cancer cells.

In the present study, we evaluated the effects of dietary histone deacetylase inhibitor sulforaphane on cell proliferation and adipogenesis in pre‐adipocytes. Mouse 3T3‐L1 pre‐adipocytes were pre‐treated with six different phytochemicals and differentiated into adipocytes. The results showed that sulforaphane significantly decreased cell viabilities of 3T3‐L1 cells compared to other phytochemicals. Furthermore, Oil Red O staining indicated that adipogenesis was inhibited by sulforaphane in a dose‐dependent manner. To understand the molecular mechanisms involved in adipogenesis inhibition by sulforaphane, we carried out oligo DNA microarray analysis. Among down‐regulated genes, we selected five genes involved in lipid metabolism and down‐regulation of those genes was confirmed by RT‐PCR and quantitative real‐time PCR. In addition, 3T3‐L1 cells were incubated with trichostatin A, sulforaphane or 5‐aza‐deoxycytidine during adipocyte differentiation and then lipid formation was evaluated with expression level of mLeptin. Interestingly, the histone deacetylase inhibitor trichostatin A and sulforaphane suppressed mLeptin expression, whereas the DNA demethylating agent 5‐aza‐deoxycytidine increased mLeptin expression. These results indicate sulforaphane exerts anti‐obesity effects via mechanisms involving epigenic down‐regulation of adipogeneic genes.