We all know “an apple a day, keeps the doctor away”, but it requires a lot of discipline to ensure that our diet contains enough vitamins. This holds especially true for the daily vitamin C uptake. Unfortunately, humans (and – for some mysterious reason – guinea pigs) lost the ability to synthesize this now essential nutrient somewhere along their way to the bipedal, fast food-consuming beings they are now.
Interestingly, vitamin C has recently been shown to constitute a direct link between metabolism and epigenetics. Vitamin C has been shown to function as an inhibitor of histone demethylases, to promote DNA-demethylation, to improve induced pluripotent stem cell generation and to stimulate a naïve pluripotent, blastocyst-like embryonic stem cell (ESC) state. In order to better understand this effect a group of researches at the Shaanxi College of Veterinary Medicine took a closer look at the influence of vitamin C on microRNA (miRNA) expression and its effect on murine ESC self-renewal.
Here is what they found:
- Vitamin C treatment increases and maintains mESC-specific miRNA expression levels.
- miRNAs of the imprinted Dlk1–Dio3 region are highly upregulated in vitamin C treated cells.
- The upregulated miRNAs target epigenetic modifiers and transcription factors involved in ESC differentiation.
- Vitamin C treatment promotes demethylation of pluripotency gene promoters potentially via modulation of Tet and Dnmt3a expression by miRNAs.
The researchers conclude that vitamin C acts primarily via promoting widespread DNA demethylation by modulating the activity of epigenetic modifiers. This leads to the upregulation of pluripotency genes and ESC-specific miRNA expression, which in turn repress factors associated with differentiation.
So grab an apple and have a look at FEBS Journal, December 2015 for all the healthy details.