Epigenetic regulation of human buccal mucosa mitochondrial superoxide dismutase gene expression by diet

Department of Nutritional Sciences, University of Vienna, Althanstrasse 14, Vienna, Austria.
The British journal of nutrition (Impact Factor: 3.45). 09/2008; 101(5):743-9. DOI: 10.1017/S0007114508047685
Source: PubMed


The impact of nutrition on the epigenetic machinery has increasingly attracted interest. The aim of the present study was to demonstrate the effects of various diets on methylation and gene expression. The antioxidative enzyme mitochondrial superoxide dismutase (MnSOD) was chosen as the model system because epigenetic regulation has been previously shown in cell lines for this gene. Promoter methylation and gene expression of MnSOD in buccal swabs from three sample groups were analysed. The three groups included: (1) forty vegetarians (aged 20-30 years); (2) age-matched omnivores; (3) elderly omnivores (aged>85 years). A 3-fold increase in the expression of the MnSOD gene was associated with decreased CpG methylation of the analysed promoter region in the vegetarian group compared with the age-matched omnivores group. Expression and promoter methylation of the MnSOD gene in elderly omnivores showed no significant differences compared with younger omnivores. In accordance with previous findings in various tissues, DNA global methylation was found to be significantly higher (30 %) in buccal swabs of younger subjects (independent of the diet), than in those of elderly omnivores. In the control experiment which was designed to verify the findings of the human buccal swab studies, the Caco-2 cell line was treated with zebularine. Results of the control study showed a 6-fold increase of MnSOD expression, an approximately 40 % decreased methylation of specified CpG in the MnSOD promoter and a 50 % reduction of global DNA methylation. These results indicate that diet affects the epigenetic regulation of human MnSOD.

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    • "Other studies have described changes on key metabolic gene methylation patterns depending on macronutrient distribution in diet-induced obesity animal models [9]. Thus, there have been also described different dietary habits that influence the epigenetic profile as vegetarian intake [16], protein-restricted diets [17] and micronutrient supplementation [18]. "
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    Molecular Genetics and Metabolism 09/2013; 110(3). DOI:10.1016/j.ymgme.2013.08.022 · 2.63 Impact Factor
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    • "Two sequential PCRs were performed to amplify the modified DNA fragments of interest [31], [32]. 1 µl of modified DNA was used in the first PCR (a) and 1 µl of PCR product was used in the subsequent PCR (b). The primers used for the SOD2 amplification were: sense primer 5′-GTA TTT TTA GGG G[C/T]G GAT [C/T]GG AGG TAG GGT TT-3′ and antisense primer 5′-CCA AAC CC[A/G] ATA C[A/G]A CCA CTA TC[A/G] CCA TTA C-3′, sense primer 5′-GGG T[C/T]G TAT TAA TTT TA[C/T] GGG GGT AGG GGT-3′ and antisense primer 5′-AAC CCC TTA CCC CTT AAA AC[A/G] TAA CC[A/G] AAT CCC-3′. "
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    PLoS ONE 05/2013; 8(5):e63456. DOI:10.1371/journal.pone.0063456 · 3.23 Impact Factor
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