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Updated: Aug 24, 2026

Generation of Human Brain Organoids for Mitochondrial Disease Modeling
Published on: June 21, 2021
Inhibition of brain mitochondrial monoamine oxidases by the endogenous compound 5-hydroxyoxindole
Michèle Crumeyrolle-Arias1, Marie-Claude Tournaire, Agnès Cane
1Laboratoire CRRET-FRE CNRS 2412, Université Paris 12 Val-de-Marne, 94010 Créteil, France. crumeyrolle@univ-paris12.fr
Abstract:
5-Hydroxyoxindole is a recently identified endogenous compound. Its physiological role remains unclear but certain evidence exists, that it may share some regulatory properties with isatin, a known endogenous inhibitor of monoamine oxidase (MAO) type B (MAO-B). In this study several oxidized indoles were tested for their in vitro inhibition of MAO type A (MAO-A) and B of rat brain non-synaptic mitochondria. 5-Hydroxyoxindole was less potent MAO-A inhibitor (IC50 56.8 microM) than isatin (31.8 microM) and especially 5-hydroxyisatin (6.5 microM), but it was the only highly selective MAO-A inhibitor among the all compounds studied (IC50 MAO-A:IC50 MAO-B = 0.044). Thus, the in vitro data suggest that MAO-A may represent potential target for 5-hydroxyoxindole.
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