| Summary: | 碩士 === 臺北醫學大學 === 保健營養學研究所 === 95 === The purpose of this study was to investigate the effect of different levels of ethanolic extract of adlay bran and residue from ethanolic extraction of adlay bran on colon carcinogenesis. Male F344 rats were fed diets containing different doses of ethanolic extract of adlay bran or residue from ethanolic extraction of adlay bran and received 1,2-dimethylhydrazine (DMH) by intraperitoneal injection. All rats were killed after 10-week feeding and colons were removed and examined for aberrant crypt foci (ACF), mucin, mucin-depleted foci (MDF) and mucosa were examined for inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2) protein expression and PGE2 concentration. The results indicated that ethanolic extract of adlay bran at levels of 0.29 %, 0.87 %, or 1.44 % and residue from ethanolic extraction of adlay bran at levels of 1.31 %, 3.93 %, or 6.56 % significantly reduced the numbers of ACF and aberrant crypts, and modified the composition of mucin on ACF. Ethanolic extract of adlay bran suppressed the formation of small ACF (1-3 aberrant crypts per focus); residue from ethanolic extraction suppressed the formation of large ACF (≧4 aberrant crypts per focus). Most ACF were found in the middle and distal colons. Ethanolic extract of adlay bran and residue from ethanolic extraction of adlay bran significantly suppressed the formation of ACF in the distal colons but did not affect the iNOS expression, COX-2 expression and PGE2 concentration of mucosa. These findings suggest that ethanolic extract of adlay bran and residue from ethanolic extraction of adlay bran may suppress colon carcinogenesis in early stage by different mechanisms.
|
|---|
