Department of Bioresource Science and Technology, Graduate School of Biosphere Science, Hiroshima University, Higashi-Hiroshima, Japan.
Mol Nutr Food Res. 2012 Apr;56(4):641-52. doi: 10.1002/mnfr.201100707.
Previous studies have shown that vitamin B6 supplementation suppresses the development of colonic aberrant crypt foci (ACF), precursor lesions of colon cancer, and cell proliferation in mice receiving the colonic carcinogen, azoxymethane (AOM). This study investigated the molecular mechanism of these effects of dietary vitamin B6.
To date, the mechanism by which ACFs develop is not yet fully understood. In a search for factors that play a critical role during ACF development, we examined colon gene expression during early stage of ACF development in AOM-treated mice using DNA microarray analysis. AOM treatment significantly upregulated mRNA closely related to mast cell and cytotoxic T-cell activity. This study also investigated the effect of vitamin B6 supplementation on colon gene expression in AOM-treated mice. We found that vitamin B6 supplementation downregulates Cd8a and Ccl8 mRNA expression, suggesting these candidate genes may play a protective role against colonic ACF development. Furthermore, we examined genomic affects of dietary vitamin B6, and showed that Reg3γ mRNA expression in colons is downregulated by vitamin B6.
This study provides an insight into the genomic activities of dietary vitamin B6 that may be protective against colon tumor development.
先前的研究表明，维生素 B6 补充剂可抑制结肠异常隐窝病灶（ACF）的发展，这是结肠癌的前体病变，以及接受结肠致癌剂氧化偶氮甲烷（AOM）的小鼠的细胞增殖。本研究探讨了饮食中维生素 B6 产生这些影响的分子机制。
迄今为止，ACF 发展的机制尚不完全清楚。为了寻找在 ACF 发展过程中起关键作用的因素，我们使用 DNA 微阵列分析研究了 AOM 处理的小鼠中 ACF 早期发展过程中的结肠基因表达。AOM 处理显著上调了与肥大细胞和细胞毒性 T 细胞活性密切相关的 mRNA。本研究还研究了维生素 B6 补充对 AOM 处理的小鼠结肠基因表达的影响。我们发现，维生素 B6 补充可下调 Cd8a 和 Ccl8 mRNA 的表达，表明这些候选基因可能对结肠 ACF 的发展具有保护作用。此外，我们还研究了饮食中维生素 B6 的基因组影响，并表明维生素 B6 可下调结肠中 Reg3γ mRNA 的表达。
本研究深入了解了饮食中维生素 B6 的基因组活性，这可能对预防结肠癌的发生具有保护作用。
