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Pathway Description
Metabolism and Physiological Effects of Trimethylamine N-oxide (TMAO)
Homo sapiens
Metabolic Pathway
Created: 2021-02-22
Last Updated: 2023-10-25
Trimethylamine N-oxide(TMAO) is a uremic toxin compound that can be metabolized from dietary choline. There are 2 metabolic reactions that occur in order to get TMAO. First choline obtained from choline rich foods such as eggs or meat enter the gut and get metabolized to trimethylamine by gut microbes. Choline gets metabolized by the enzyme complex CutC/D into trimethylamine. This trimethylamine then enters a liver hepatocyte through portal circulation and gets metabolized by FMO3 to form TMAO. When this compound enters into systemic circulation it is shown to be a major uremic toxin when high levels of it are retained in the blood and not excreted in urine. TMAO is shown to cause coronary atherosclerosis, renal fibrosis through interaction with TGF-β1/Smad3 pathway, and increased mitochondrial reactive oxygen species which can cause oxidative stress.
References
Metabolism and Physiological Effects of Trimethylamine N-oxide (TMAO) References
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