Possible anti-tumour-promoting activity of components in Japanese soybean fermented food, Natto: effect on gap junctional intercellular communication.
In order to detect any protective agent against tumor formation, we examined the anti-tumor-promoting effect of a Japanese traditional soybean fermented food, Natto. Dye transfer was employed as an assay method. When fluorescent dye was microinjected into cultured BALB/3T3 cells, the dye was transformed into the neighboring cells through the gap junction. This dye transfer was blocked by the treatment with the tumor promoters 12-O-tetra-decanoylphorbol-13-acetate (TPA), a high concentration of NaCl and lithocholic acid (LCA). This reduction of the dye transfer by TPA treatment was not observed when the cells were pretreated with retinoic acid, an anti-tumor promoter. Thus, the recovery of the dye transfer in TPA-treated BALB/3T3 cells was proven to ge a good indicator for detecting some possible anti-tumor promoters. After extraction and fractionation of Natto, we obtained an active fraction (H1) which showed recovery of the dye transfer in TPA-treated cells. The fraction contained straight-chain saturated hydrocarbons. A comparison of the fraction and the authentic samples by GC analysis suggests that the H1 fraction contained straight-chain saturated hydrocarbons from around C30 to C32. Among these hydrocarbons, hentriacontane (C31) was found at the highest concentrations, and was shown to have the highest activity. Hentriacontane at a very low concentration of 0.65 ng/ml was shown to recover the dye transfer inhibited by the treatment with TPA as well as with NaCl and LCA.
Takahashi
C
C
Department of Brewing and Fermentation, Faculty of Agriculture, Tokyo University of Agriculture, Japan.
Kikuchi
N
N
Katou
N
N
Miki
T
T
Yanagida
F
F
Umeda
M
M
D016475:3T3 Cells; D000818:Animals; D016588:Anticarcinogenic Agents / Q000494:pharmacology*; D002450:Cell Communication / Q000187:drug effects*; D005285:Fermentation; D005456:Fluorescent Dyes; D005504:Food Analysis; D017629:Gap Junctions / Q000187:drug effects*; D007564:Japan; D008095:Lithocholic Acid; D051379:Mice; D012965:Sodium Chloride; D013025:Glycine max / Q000737:chemistry*
D016588:Anticarcinogenic Agents; D005456:Fluorescent Dyes; D012965:Sodium Chloride; D008095:Lithocholic Acid