A decreased micronucleus frequency in human lymphocytes after folate and vitamin B12 intervention: A preliminary study in a yunnan population

摘要

Background: 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 Binf12/inf are one-carbon metabolism-related micronutrients, which play important roles in maintaining genomic stability. Objective: To investigate the correcting effects of FA and B12 intervention on DNA damage in PBL. Method: 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. Results: 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. Conclusion: Dietary supplement intake of FA and Binf12/inf based on MTHFR genotypes could protect the genome from damage and benefit genome health.