Extensive Summary of the Important Roles of Indole Propionic Acid, a Gut Microbial Metabolite in Host Health and Disease

Abstract

Increasing evidence suggests that metabolites produced by the gut microbiota play a crucial role in host–microbe interactions. Dietary tryptophan ingested by the host enters the gut, where indole-like metabolites such as indole propionic acid (IPA) are produced under deamination by commensal bacteria. Here, we summarize the IPA-producing bacteria, dietary patterns on IPA content, and functional roles of IPA in various diseases. IPA can not only stimulate the expression of tight junction (TJ) proteins to enhance gut barrier function and inhibit the penetration of toxic factors, but also modulate the immune system to exert anti-inflammatory and antioxidant effects to synergistically regulate body physiology. Moreover, IPA can act on target organs through blood circulation to form the gut–organ axis, which helps maintain systemic homeostasis. IPA shows great potential for the diagnosis and treatment of various clinical diseases, such as NAFLD, Alzheimer’s disease, and breast cancer. However, the therapeutic effect of IPA depends on dose, target organ, or time. In future studies, further work should be performed to explore the effects and mechanisms of IPA on host health and disease to further improve the existing treatment program.

Urine and serum metabolomics study of wild ginseng in rats with spleen‐qi deficiency using rapid resolution liquid chromatography coupled with quadrupole‐time‐of‐flight mass spectrometry

“…Tryptamine and its metabolites are closely associated with intestinal flora homeostasis [25]. Indole, an abundant metabolite of the tryptamine indole metabolic pathway, is often regarded as an intercellular signaling molecule that protects the organism against intestinal pathogens [26]. In this study, the relative levels of tryptamine ( p < 0.01) and 19‐hydroxytestosterone ( p < 0.01) were increased after WG treatment.…”

Gut Microbiota and Microbial Metabolism in Early Risk of Cardiometabolic Disease

“…191 Phenylacetylglutamine has been shown to modulate adrenergic receptor signaling and is linked to increased risk of thrombosis and heart failure. 192,193 Indole-3-propionic acid (IPA) is a microbe-derived metabolite of tryptophan, which acts as an antibiotic and has been suggested to be protective in disease, exhibiting anti-inflammatory and antioxidant function 194,195 and modulation of cholesterol efflux. 196 Higher IPA has been associated with higher gut microbiome diversity.…”

Photoinduced Decarboxylative Borylation of N-Hydroxyphthalimide Esters with Hypoboric Acid

“…Indole 3-propionic acid occurs as a plant or bacterial metabolite and has ongoing research in Alzheimer's disease. 24,25 Its corresponding ester provided the boronic ester (2am) in a good yield. Secondary NHPI esters (1ba−1bg) were utilized in the transformation to produce pinacol esters in moderate to excellent yields.…”

“…The stearic acid derivative 1al was borylated successfully under our conditions. Indole 3-propionic acid occurs as a plant or bacterial metabolite and has ongoing research in Alzheimer’s disease. , Its corresponding ester provided the boronic ester ( 2am ) in a good yield.…”