The authors used a metabolomics approach to identify small molecules in plasma that are associated with the risk of developing cardiovascular disease. Subsequent studies with germ-free mice demonstrated the critical role that the microbial species in the gastrointestinal tract play in the development of trimethylamine N-oxide (TMAO), which in turn enables the development of atherosclerosis.

Inhibition of the growth of gastrointestinal microflora in atherosclerosis-prone mice resulted in a reduction of dietary choline-enhanced atherosclerosis. This study demonstrates a clear relationship between gut microbial species, their metabolism of phosphatidylcholine in the diet and the development of cardiovascular disease. It serves as a model for the value of omics-based approaches to evaluate the role of the human microbiome in health and disease, and presents novel approaches to the development of diagnostics and therapeutics in the treatment of heart disease....