Trimethylamine N-oxide: breathe new life

Br J Pharmacol. 2018 Apr;175(8):1344-1353. doi: 10.1111/bph.13959. Epub 2017 Aug 30.


Association between elevated levels of systemic trimethylamine N-oxide (TMAO) and increased risk for adverse cardiovascular events have been proposed in recent years. Increasing experimental and clinical evidence in the last decade has implicated TMAO as an important contributor to the pathogenesis of cardiovascular diseases. TMAO, the oxygenated product of trimethylamine (TMA), belongs to the class of amine oxides. Most of the TMA derived from the metabolism of choline and L-carnitine by gut bacteria is absorbed into the bloodstream and gets rapidly oxidized to TMAO by the hepatic enzyme, flavin-containing monooxgenase-3. Here, we discussed the biosynthesis of TMAO and clinical studies that have assessed TMAO as a biomarker for various cardiovascular and other diseases such as kidney failure, thrombosis, atherosclerosis, obesity, diabetes and cancer. We also summarized the interaction of TMAO with synthetic and traditional molecules that together affect circulating TMAO levels.

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Publication types

  • Review

MeSH terms

  • Animals
  • Brain Diseases / metabolism
  • Heart Failure / metabolism
  • Humans
  • Methylamines / metabolism*
  • Neoplasms / metabolism
  • Obesity / metabolism
  • Thrombosis / metabolism


  • Methylamines
  • trimethyloxamine