In laboratory-grown human intestinal cells, adding vitamin B12 at a specific concentration is linked to changes in DNA methylation patterns in genes that control cell growth and intestinal barrier...
Mechanism
Synthesis from 1 study
Vitamin B12 gives cells the raw material to add chemical tags to DNA, which tells certain genes to turn on or off. These tags help gut cells grow properly and build a stronger barrier, while turning down genes that cause inflammation. The energy boost from vitamin B12 helps this process run...
Most probable mechanism
Vitamin B12 helps convert a waste molecule into a key chemical that adds methyl tags to DNA, which turns certain genes on or off. These tags silence genes that cause inflammation and turn on genes that help the gut lining grow and repair itself, making the barrier stronger and more stable.
Vitamin B12 acts as a cofactor for methionine synthase, enabling the conversion of homocysteine to methionine.
Methionine is converted into S-adenosylmethionine (SAM), the primary methyl donor for DNA methylation reactions.
SAM provides methyl groups to DNA methyltransferases, which add methyl groups to CpG sites in gene promoters and enhancers.
Hypermethylation of enhancer regions in genes like PTGER2, SHH, and CHST11 increases their expression, promoting cell proliferation.
Hypomethylation of promoter regions in MUC13 increases its expression, enhancing mucus production and intestinal barrier integrity.
Hypermethylation of enhancer regions in pro-inflammatory genes like ERRFI1 reduces their expression, suppressing inflammatory signaling.
Global CpG methylation increases as a result of elevated SAM availability, stabilizing the epigenetic state of epithelial cells.
Less supported by current evidence, but not ruled out
Vitamin B12 helps cells produce energy more efficiently by enabling the breakdown of fatty acids and the recycling of metabolic intermediates, which may provide the energy needed for DNA methylation processes.
Vitamin B12 activates methylmalonyl-CoA mutase, converting methylmalonyl-CoA to succinyl-CoA, which enters the TCA cycle.
Succinyl-CoA replenishes TCA cycle intermediates, boosting ATP production and biosynthetic precursors.
Vitamin B12 enhances carnitine-dependent fatty acid transport into mitochondria, increasing beta-oxidation and energy yield.
Increased ATP and metabolic intermediates support the energy-intensive process of DNA methylation and gene regulation.
Evidence from Studies
Supporting (1)
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Vitamin B12 Regulates the Transcriptional, Metabolic, and Epigenetic Programing in Human Ileal Epithelial Cells
Contradicting (0)
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