Indoxyl sulfate (IS)

Indoxyl sulfate is a potent protein-bound uremic toxin derived from the microbial metabolism of dietary tryptophan in the gut. It is synthesized in the liver from indole and normally excreted by the kidneys via tubular secretion. In patients with chronic kidney disease (CKD), it accumulates significantly due to impaired renal clearance and poor removal by conventional hemodialysis. Indoxyl sulfate acts as an endogenous agonist for the aryl hydrocarbon receptor (AhR) and promotes oxidative stress, inflammation, and fibrosis in various tissues. Its accumulation is strongly associated with the progression of renal failure, cardiovascular complications, and bone disease, making it a key target for therapeutic interventions aimed at reducing its systemic levels or blocking its downstream signaling.

Other names

3-Indoxyl sulfate3-Indoxylsulfuric acidIndol-3-yl sulfateIndicanPotassium indoxyl sulfate

Gastrointestinal adsorption of indole precursors (AST-120), inhibition of organic anion transporters OAT1 and OAT3 (Probenecid), and antagonism of downstream signaling pathways (Losartan).