In vitro inhibition of glutathione-S-transferase by dopamine and its metabolites, 3,4-dihydroxyphenylacetaldehyde and 3,4-dihydroxyphenylacetic acid.
Neurotoxicology
; 86: 85-93, 2021 09.
Article
en En
| MEDLINE
| ID: mdl-34314733
ABSTRACT
Parkinson's disease is characterized by dopamine dyshomeostasis and oxidative stress. The aldehyde metabolite of dopamine, 3,4-dihydroxyphenylacetaldehyde (DOPAL), has been reported to be cytotoxic and capable of protein modification. Protein modification by DOPAL has been implicated in the pathogenesis of Parkinson's disease, but the complete pathology is unknown. Our findings show that DOPAL modifies glutathione S-transferase (GST), an important enzyme in the antioxidant defense system. DOPAL, dopamine, and the metabolite 3,4-dihydroxyphenylacetic acid (DOPAC), inhibited the activity of GST isolated from N27 dopaminergic cells at an IC50 of 31.46 µM, 82.32 µM, and 260.0 µM, respectively. DOPAL, dopamine, and DOPAC inhibited commercially available equine liver GST at an IC50 of 23.72 µM, 32.17 µM, and 73.70 µM, respectively. This inhibition was time dependent and irreversible. 1 mM Ê-cysteine or glutathione fully protected GST activity from DOPAL, DA, and DOPAC inhibition. 1 mM carnosine partially protected GST activity from DA inhibition. Furthermore, Ê-cysteine was found to protect GST by forming a putative thiazolidine conjugate with DOPAL. We conclude that GST inactivation may be a part of the broader etiopathology of Parkinson's disease.
Palabras clave
Texto completo:
1
Colección:
01-internacional
Banco de datos:
MEDLINE
Asunto principal:
Ácido 3,4-Dihidroxifenilacético
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Dopamina
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Neuronas Dopaminérgicas
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Glutatión Transferasa
Límite:
Animals
Idioma:
En
Revista:
Neurotoxicology
Año:
2021
Tipo del documento:
Article
País de afiliación:
Estados Unidos