Indole-3-propionic acid is a bacterial metabolite that has antioxidant and neuroprotective activities.1,2,3 It scavenges ABTS radicals in a cell-free assay when used at concentrations ranging from 50 to 150 ?M and decreases hydrogen peroxide-induced malondialdehyde (MDA) levels in rat striatal membranes (IC50 = 180 ?M).2 Indole-3-propionic acid also decreases increases in MDA levels induced by amyloid β (1-42) in PC12 cells.4 It decreases ischemia-induced increases in cell death of pyramidal neurons and levels of 4-hydroxy nonenal and glial fibrillary acidic protein (GFAP) in the hippocampal CA1 region in gerbils when administered at a dose of 10 mg/kg per day.3
1.Wikoff, W.R., Anfora, A.T., Liu, J., et al.Metabolomics analysis reveals large effects of gut microflora on mammalian blood metabolitesProc. Natl. Acad. Sci. USA106(10)3698-3703(2009) 2.Poeggeler, B., Pappolla, M.A., Hardeland, R., et al.Indole-3-propionate: A potent hydroxyl radical scavenger in rat brainBrain Res.815(2)382-388(1999) 3.Hwang, I.K., Yoo, K.-Y., Li, H., et al.Indole-3-propionic acid attenuates neuronal damage and oxidative stress in the ischemic hippocampusJ. Neurosci. Res.87(9)2126-2137(2009) 4.Chyan, Y.-J., Poeggeler, B., Omar, R.A., et al.Potent neuroprotective properties against the Alzheimer β-amyloid by an endogenous melatonin-related indole structure, indole-3-propionic acidJ. Biol. Chem.274(31)21937-21942(1999)