3-Indolepropionic acid (IPA), or indole-3-propionic acid, is a potent

neuroprotective Neuroprotection refers to the relative preservation of neuronal structure and/or function. In the case of an ongoing insult (a neurodegenerative insult) the relative preservation of neuronal integrity implies a reduction in the rate of neuronal los ...

antioxidant Antioxidants are compounds that inhibit oxidation, a chemical reaction that can produce free radicals. This can lead to polymerization and other chain reactions. They are frequently added to industrial products, such as fuels and lubricants, ...

, plant

auxin Auxins (plural of auxin ) are a class of plant hormones (or plant-growth regulators) with some morphogen-like characteristics. Auxins play a cardinal role in coordination of many growth and behavioral processes in plant life cycles and are essenti ...

, and natural product in humans that is being studied for therapeutic use in

Alzheimer's disease Alzheimer's disease (AD) is a neurodegenerative disease that usually starts slowly and progressively worsens. It is the cause of 60–70% of cases of dementia. The most common early symptom is difficulty in remembering recent events. As ...

. It is endogenously produced by human microbiota and has only been detected '' in vivo'' when the species ''

Clostridium sporogenes ''Clostridium sporogenes'' is a species of Gram-positive bacteria that belongs to the genus ''Clostridium''. Like other strains of ''Clostridium'', it is an anaerobic, rod-shaped bacterium that produces oval, subterminal endospores and is commonl ...

'' is present in the gastrointestinal tract. , ''C. sporogenes'', which uses

tryptophan Tryptophan (symbol Trp or W) is an α-amino acid that is used in the biosynthesis of proteins. Tryptophan contains an α-amino group, an α-carboxylic acid group, and a side chain indole, making it a polar molecule with a non-polar aromatic ...

to synthesize IPA, is the only species of bacteria known to synthesize IPA ''in vivo'' at levels which are subsequently detectable in the

blood plasma Blood plasma is a light amber-colored liquid component of blood in which blood cells are absent, but contains proteins and other constituents of whole blood in suspension. It makes up about 55% of the body's total blood volume. It is the intr ...

of the host. IPA is an even more potent scavenger of hydroxyl radicals than melatonin, the most potent scavenger of hydroxyl radicals that is synthesized by human enzymes. Similar to melatonin but unlike other antioxidants, it scavenges radicals without subsequently generating reactive and pro-oxidant intermediate compounds. In 2017, elevated concentrations of IPA in human

were found to be correlated with a lower risk of type 2 diabetes and higher consumption of fiber-rich foods.

Biosynthesis in humans and cellular effects

Metabolism

IPA can be converted in the liver or

kidneys The kidneys are two reddish-brown bean-shaped organs found in vertebrates. They are located on the left and right in the retroperitoneal space, and in adult humans are about in length. They receive blood from the paired renal arteries; blood ...

to 3-indoleacrylic acid, which is subsequently conjugated with glycine, forming indolylacryloyl glycine.

History

The neuroprotective, antioxidant, and anti-amyloid properties of IPA were first reported by a group of investigators in July 1999, led by Dr. Pappolla and Dr. Poeggeler at the University of South Alabama.

References

{{DEFAULTSORT:Indolepropionic acid, 3- Antioxidants Indoles Propionic acids Auxins Biomolecules

Biosynthesis in humans and cellular effects

Metabolism

History

See also

References