L-Kynurenine (Beta-Anthraniloyl-L-Alanine) is an endogenous agonist for the cytosolic aryl hydrocarbon receptor (AhR) transcription factor [1].
L-Kynurenine is the first byproduct of tryptophan metabolism generated via the enzymatic “kynurenine pathway”, which produces other kynunerine derivatives [2]. L-Kynurenine is implicated in the production of TGF-β and expansion of regulatory T cells through the AhR-Src-IDO1 pathway [1]. Yet, L-Kynurenine mode of action on AhR is still unclear. Indeed, it could be a low-affinity AhR pro-ligand that is slowly converted in high-affinity compounds acting as AhR agonists at subnanomolar concentrations. This conversion occurs independently of enzymes, when fresh crystalline L-Kynurenine is resuspended as a solution, and gives rise to trace-amounts of derivatives named TEACOPs (trace-extended aromatic condensation products) [3].
InvivogGen's L-Kynurenine is a high quality product (> 95% purity) and is guaranteed free of bacterial contamination. Each lot of L-Kynurenine is functionally tested in cellular assays using HepG2-Lucia™ AhR and HT29-Lucia™ AhR reporter cells.
Other AhR ligands, as well as an AhR antagonist are also available.
References:
- Bessede A. et al., 2014. Aryl hydrocarbon receptor control of a disease tolerance defence pathway. Nature. 511:184-90.
- Hubbard T.D. et al., 2015. Indole and tryptophan metabolism: endogenous and dietary routes to Ah receptor activation. Drug Metab. Dispos. 43:1522-35.
- Seok, S.H. et al., 2018. Trace derivatives of kynurenine potently activate the aryl hydrocarbon receptor (AHR). J. Biol. Chem. 293:1994-2005.