In laboratory-grown human intestinal cells, adding vitamin B12 at a concentration of 500 nanomolars is linked to higher activity of genes that support mitochondrial energy production from fatty acids.
Mechanism
Synthesis from 1 study
Vitamin B12 helps gut cells burn fat for energy by helping move fat into their power plants and keeping those power plants running smoothly. It also turns off signals that cause inflammation, letting the cells focus on making energy instead of fighting stress.
Most probable mechanism
Vitamin B12 helps cells make more methionine, which is used to create a molecule called carnitine that shuttles fat into the energy factories of the cell. Once inside, the fat is broken down and fed into a cycle that generates energy and building blocks for the cell. At the same time, vitamin B12 helps convert a waste product into a key ingredient for that energy cycle, making it run more efficiently. This boosts the cell’s ability to produce energy from fat instead of sugar.
Vitamin B12 acts as a cofactor for methionine synthase, enabling the conversion of homocysteine to methionine.
Methionine is used to synthesize S-adenosylmethionine (SAM), which supports carnitine biosynthesis and epigenetic regulation of metabolic genes.
Carnitine facilitates the transport of long-chain fatty acids into mitochondria through the carnitine shuttle proteins CPT1A and SLC25A20.
Fatty acids undergo beta-oxidation within mitochondria, producing acetyl-CoA and other intermediates that feed into the TCA cycle.
Vitamin B12 activates methylmalonyl-CoA mutase, converting methylmalonyl-CoA to succinyl-CoA, which directly replenishes TCA cycle intermediates.
Succinyl-CoA and acetyl-CoA drive increased TCA cycle flux, upregulating enzymes IDH2 and SUCLG1 to enhance ATP and biosynthetic precursor production.
Epigenetic modifications via SAM-dependent DNA methylation activate promoters of fatty acid oxidation and TCA cycle genes while suppressing inflammatory pathways.
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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