Buccal Cytome Biomarkers and Their Association with Plasma Folate, Vitamin B12 and Homocysteine in Alzheimer's Disease

Background/Aims: Alzheimer's disease (AD) is an irreversible neurodegenerative disorder and is the commonest form of dementia. One aim of this study was to determine whether AD individuals have altered plasma folate, vitamin B-12 and homocysteine (Hcy) levels compared to controls. The other aim was to investigate correlations between B vitamins and buccal bio-markers to test whether they are influenced by B vitamin status. Methods: Folate, vitamin B-12 and Hcy were measured using ARCHITECT (R) and AxSYM (R) assays. Genomic stability was measured using the buccal micronucleus cytome assay. Results: The area under the receiver operating characteristic curve for AD basal cells was 0.96 (p < 0.0001), for karyorrhectic cells 0.88 (p < 0.0001) and for basal and karyorrhectic cells 0.91 (p < 0.0001). Hcy was significantly increased (p = 0.0003) compared to controls. Plasma vitamin B-12 in controls showed a positive correlation with pyknosis (r = 0.5365, p = 0.004), karyolysis (r = 0.5447, p = 0.004) and condensed chromatin (r = 0.5238, p = 0.006). Plasma vitamin B-12 in AD cases showed a positive correlation with micronuclei (r = 0.3552, p = 0.04) and basal cells (r = 0.3448, p = 0.04), whilst plasma Hcy showed a negative correlation with karyorrhectic cells (r = 0.4107, p = 0.01). Conclusions: Hcy was significantly increased in AD cases relative to controls. The lower frequency of basal cells and karyorrhectic cells observed in AD cases may be explained by lower vitamin B-12 and higher Hcy levels, respectively. (C) 2015 S. Karger AG, Basel