| Potassium 1H-indol-3-yl sulfate (Potassium 3-indoxyl sulfate) is an agonist for the human Aryl Hydrocarbon Receptor (AhR), a key regulator of immune-inflammatory conditions. A metabolite of tryptophan derived from dietary protein, it is produced by intestinal bacteria and metabolized in the liver. In chronic kidney disease patients with impaired renal function, it accumulates in serum as a uremic toxin, inducing oxidative stress and accelerating disease progression. At 250 µM, it activates NF-b, promoting TGF-beta1 and Smad3 expression in rat proximal tubular cells, which is associated with profibrotic activity. |