Piyathilake C J, Macaluso M, Hine R J, Vinter D W, Richards E W, Krumdieck C L
Department of Nutrition Sciences, University of Alabama at Birmingham 35294, USA.
Cancer Epidemiol Biomarkers Prev. 1995 Oct-Nov;4(7):751-8.
The study focuses on the assessment of chromosomal damage associated with folate and vitamin B12 deficiency, and with cigarette smoking in a tissue directly exposed to cigarette smoke (buccal mucosa) while controlling for potential confounding factors. A cross-sectional study was carried out among 39 current smokers (CSs) and 60 noncurrent smokers (NCSs). Buccal mucosal cells, saliva, and blood samples were collected from each subject. The Health Habits and History Questionnaire (Block et al., 1986) was modified to obtain dietary and other relevant information. Methods used to measure folate, vitamin B12 levels, and the frequency of micronucleated cells in buccal mucosal cells gave reproducible results. The study results suggest that CSs have buccal mucosal folate and vitamin B12 levels that are lower than those among NCSs. CSs were three times more likely to have micronucleated buccal mucosal cells compared to NCSs. There appeared to be no association between low buccal folate and vitamin B12 levels chromosomal damage. The salivary vitamin B12 concentrations and plasma vitamin C and E concentrations, however, seem to be marginally protective against the occurrence of buccal mucosal micronuclei, whereas plasma beta-carotene seems to increase the occurrence of micronuclei. Overall, the results do not support the concept that localized folate and vitamin B12 deficiencies in the buccal mucosal cells of smokers are associated with chromosomal damage in those cells. The presence of vitamin B12 deficiencies in the buccal mucosal cells of smokers are associated with chromosomal damage in those cells. The presence of vitamin B12 in the immediate environment (saliva) and vitamin C and E in the plasma, however, appear to be marginally protective against chromosomal damage in buccal mucosal cells.
该研究聚焦于评估与叶酸和维生素B12缺乏相关的染色体损伤，以及在直接暴露于香烟烟雾的组织（颊黏膜）中吸烟对染色体损伤的影响，同时控制潜在的混杂因素。对39名当前吸烟者（CSs）和60名非当前吸烟者（NCSs）进行了一项横断面研究。从每个受试者收集颊黏膜细胞、唾液和血液样本。对《健康习惯与病史问卷》（Block等人，1986年）进行了修改，以获取饮食和其他相关信息。用于测量叶酸、维生素B12水平以及颊黏膜细胞中微核细胞频率的方法给出了可重复的结果。研究结果表明，CSs的颊黏膜叶酸和维生素B12水平低于NCSs。与NCSs相比，CSs出现颊黏膜微核细胞的可能性高出三倍。颊部叶酸和维生素B12水平低与染色体损伤之间似乎没有关联。然而，唾液中维生素B12浓度以及血浆中维生素C和E浓度似乎对颊黏膜微核的发生有一定的保护作用，而血浆β-胡萝卜素似乎会增加微核的发生。总体而言，结果不支持吸烟者颊黏膜细胞中局部叶酸和维生素B12缺乏与这些细胞中的染色体损伤相关的概念。吸烟者颊黏膜细胞中维生素B12缺乏与这些细胞中的染色体损伤相关。然而，直接环境（唾液）中维生素B12的存在以及血浆中维生素C和E的存在似乎对颊黏膜细胞中的染色体损伤有一定的保护作用。
