Fenech M, Rinaldi J
CSIRO Division of Human Nutrition, Adelaide, Australia.
Carcinogenesis. 1994 Jul;15(7):1405-11. doi: 10.1093/carcin/15.7.1405.
The cytokinesis-block micronucleus assay is increasingly being applied to the study of spontaneous or induced genetic damage in human lymphocytes, but little is known about dietary and other lifestyle factors that could influence this index. As part of a larger study investigating the role of dietary factors on baseline genetic damage in human lymphocytes from 152 non-smoking females and 113 non-smoking males evenly distributed between the ages of 20 and 87 years, we have measured (a) the micronucleus (MN) frequency and (b) the plasma level of the anti-oxidant vitamins C and E and the B vitamins folic acid and B12. Multiple regression analysis indicated that age (beta value = 0.598, P < 0.0001) was the most important factor influencing the variance of micronucleus frequency in females, while micronutrient levels had no apparent significant effects on genetic damage. In males age was also the predominant factor (beta value = 0.505, P < 0.0001) influencing genetic damage, but vitamin-C level also contributed positively and significantly to the observed MN frequency (beta value = 0.220, P < 0.0228). To avoid the potential confounding effect of collinearity between variables we also performed separate simple regression analysis for each plasma micronutrient in relation to age-adjusted micronucleus frequency; the results from this analysis again showed a significant and positive effect of plasma vitamin C on age-adjusted micronucleus frequency in males only (beta value = 0.188, P = 0.0503), while no effect was observed for the other micronutrients in both sexes. In view of the predominant age effect, we also focused on the data obtained in the youngest age groups of both sexes. In view of the predominant age effect, we also focused on the data obtained in the youngest age groups of both sexes (i.e. 20-30 years olds) and found (a) that the MN frequency in young males is significantly and positively correlated with plasma vitamin C levels (r = 0.823, P < 0.001) but negatively correlated with plasma vitamin B12 status (r = -0.799, P < 0.001) and (b) in females the only significant correlation was an inverse relationship between MN frequency and the combined folate and vitamin B12 plasma levels (r = -0.4632, P < 0.030).(ABSTRACT TRUNCATED AT 400 WORDS)
胞质分裂阻滞微核试验越来越多地应用于人类淋巴细胞自发或诱导性基因损伤的研究，但对于可能影响该指标的饮食及其他生活方式因素却知之甚少。作为一项更大规模研究的一部分，该研究旨在调查饮食因素对152名年龄在20至87岁之间的非吸烟女性和113名非吸烟男性的人类淋巴细胞基线基因损伤的作用，我们测量了：（a）微核（MN）频率，以及（b）抗氧化维生素C和E、B族维生素叶酸和维生素B12的血浆水平。多元回归分析表明，年龄（β值 = 0.598，P < 0.0001）是影响女性微核频率方差的最重要因素，而微量营养素水平对基因损伤无明显显著影响。在男性中，年龄也是影响基因损伤的主要因素（β值 = 0.505，P < 0.0001），但维生素C水平也对观察到的MN频率有显著正向贡献（β值 = 0.220，P < 0.0228）。为避免变量之间共线性的潜在混杂效应，我们还针对每种血浆微量营养素与年龄调整后的微核频率进行了单独的简单回归分析；该分析结果再次表明，仅血浆维生素C对男性年龄调整后的微核频率有显著正向影响（β值 = 0.188，P = 0.0503），而在两性中其他微量营养素均无影响。鉴于年龄的主要影响，我们还关注了两性最年轻年龄组（即20至30岁）的数据。鉴于年龄的主要影响，我们还关注了两性最年轻年龄组（即20至30岁）的数据，发现：（a）年轻男性的MN频率与血浆维生素C水平显著正相关（r = 0.823，P < 0.001），但与血浆维生素B12水平呈负相关（r = -0.799，P < 0.001）；（b）在女性中，唯一显著的相关性是MN频率与血浆叶酸和维生素B12联合水平之间的负相关关系（r = -0.4632，P < 0.030）。（摘要截选至400字）
