School of Life Sciences, Yunnan Normal University, The Engineering Research Center of Sustainable Development and Utilization of Biomass Energy, Ministry of Education, Kunming, Yunnan, China.
Int J Vitam Nutr Res. 2012 Dec;82(6):374-82. doi: 10.1024/0300-9831/a000134.
Micronucleus (MN) is a validated biomarker for DNA damage in peripheral blood lymphocytes (PBL) and is a reflection of the changes of human nutritional status. Folate (FA) and vitamin B(12) are one-carbon metabolism-related micronutrients, which play important roles in maintaining genomic stability.
To investigate the correcting effects of FA and B(12) intervention on DNA damage in PBL.
One hundred fifty-six volunteers without history of cancer were divided into 5 age groups (20 - 69 y, 47.4 % male) for establishing the baseline of chromosomal damage by means of cytokinesis-block micronucleus assay. Twelve individuals whose MN frequency was higher than the median value in each age group were selected for a four-month FA (200 - 400 μg/day)-B12 (3.125 - 25 μg/day) intervention dosed as to age and MTHFR genotypes.
There were significantly positive correlations between age and MN frequency in all groups (p < 0.01). Among all age groups, the baseline MN frequencies were higher in females than that in males. The MN frequencies from 10 volunteers were reduced by 33.5 % after the intervention with the two micronutrients (p < 0.01), and two individuals did not show any changes.
Dietary supplement intake of FA and B(12) based on MTHFR genotypes could protect the genome from damage and benefit genome health.
微核（MN）是外周血淋巴细胞（PBL）DNA 损伤的有效生物标志物，反映了人类营养状况的变化。叶酸（FA）和维生素 B（12）是一碳代谢相关的微量营养素，在维持基因组稳定性方面发挥着重要作用。
研究 FA 和 B（12）干预对 PBL 中 DNA 损伤的纠正作用。
将 156 名无癌症病史的志愿者分为 5 个年龄组（20-69 岁，47.4%为男性），通过细胞分裂阻断微核试验建立染色体损伤的基线。在每个年龄组中，选择 MN 频率高于中位数的 12 人，根据年龄和 MTHFR 基因型给予 FA（200-400μg/d）-B12（3.125-25μg/d）干预。
所有组的 MN 频率与年龄均呈显著正相关（p<0.01）。在所有年龄组中，女性的 MN 频率均高于男性。在接受两种微量营养素干预后，10 名志愿者的 MN 频率降低了 33.5%（p<0.01），有两人没有任何变化。
基于 MTHFR 基因型的 FA 和 B（12）膳食补充可以保护基因组免受损伤，有益于基因组健康。
