Uremic toxins in the gut lumen (UTs)

Uremic toxins in the gut lumen are a diverse group of compounds, primarily derived from the microbial fermentation of dietary proteins (such as tryptophan and tyrosine), that accumulate in the systemic circulation of patients with Chronic Kidney Disease (CKD). In healthy individuals, these metabolites are efficiently cleared by the kidneys; however, in renal failure, they reach toxic concentrations, contributing to the 'gut-kidney axis' pathology characterized by systemic inflammation, oxidative stress, and accelerated cardiovascular damage (Vaziri et al., 2013; Duranton et al., 2012). Many of these toxins, such as indoxyl sulfate and p-cresyl sulfate, are highly protein-bound, making them difficult to remove through conventional hemodialysis. Therapeutic strategies focus on the gut lumen as a site for intervention to reduce the systemic burden of these solutes. Oral adsorbents like AST-120 work by sequestering these toxins and their precursors directly in the intestines to facilitate fecal excretion, while biotics (pre-, pro-, and synbiotics) aim to modulate the gut microbiota to decrease the initial production of these harmful metabolites (Asai et al., 2019; Ramezani et al., 2014).

Other names

Gut-derived uremic toxinsProtein-bound uremic toxinsMicrobial uremic metabolitesUremic retention solutesGut-derived uremic precursors

Physical adsorption and sequestration of uremic solutes and their precursors within the gastrointestinal tract to prevent systemic absorption and promote fecal elimination, or modulation of the gut microbiota to decrease toxin synthesis.