Indole-3-acetate

What is measured?

3-Indoxyl sulfate (3IS), indole-3-acetamide (IAM), indole-3-acetate (IAA), indole-3-aldehyde (IAld), indole-3-lactate (ILA) and indole-3-propionate (IPA). Method(s): LC-MS/MS ( 1 ).

Indication(s)

Profiling of microbiota-derived metabolites.

Specimen, collection and processing

Volume: Minimum volume is 60 µL, but 200 µL is optimal and allows reanalysis. Preparation and stability: Samples should be put on ice immediately after collection and stored at -80 °C.

Transportation

Frozen, on dry ice.

Reported values

Reported values: 3IS: 0.9-30 µmol/L; IAM: 0-10 nmol/L; IAA: 0.3-23 µmol/L; IAld: 10-200 nmol/L; ILA: 0.08-5 µmol/L; IPA: 0.5-12 µmol/L. Intraclass correlation coefficient (ICC): na.

Literature

1 . Midttun, O., Hustad, S., and Ueland, P.M. (2009). Quantitative profiling of biomarkers related to B-vitamin status, tryptophan metabolism and inflammation in human plasma by liquid chromatography/tandem mass spectrometry. Rapid Commun Mass Sp 23, 1371-79. 2 . Roager, H. M., & Licht, T. R. (2018). Microbial tryptophan catabolites in health and disease. Nat Commun, 9, 3294.