Abstract
Rare sugars are monosaccharides that exist in a very small amount in nature. Therefore, the physiological functions of rare sugars have not been well studied yet. We have found the inhibitory effect of one of the rare sugars, D-allose, on proliferation of Huh-7 hepatoma cells. Target genes of D-allose were examined using the microarray techniques. Total RNAs purified from the 50 mM D-allose treated or untreated cells were labeled with fluorescent dyes (Cy-3 or Cy-5) and hybridized to the Agilent human 1A microarray containing approximately 20,000 genes. The slide was washed and signals were measured by the microarray scanner. Genes showing a significant expression level change were chosen and further analyzed by realtime PCR method. Our study revealed that the expression of the vitamin D3 up-regulated protein (VDUP), which was reported to induce a cell cycle arrest increased significantly. This increase was specific to the D-allose treatment and was not observed by other sugars such as D-glucose, D-psicose treatment. The MTT assay showed the proliferation inhibiting effect of D-allose on Huh-7 cells and the flow cytometry analysis indicated that D-allose caused the G0/G1 cell cycle arrest. These result suggested that D-allose may inhibit the Huh-7 cell proliferation by activating the VDUP gene pathway. [Jpn J Physiol 55 Suppl:S82 (2005)]
