Inhibitory effect of dehydroepiandrosterone on brain monoamine oxidase activity: in vivo and in vitro studies.
OBJECTIVE
To evaluate the acute effect of dehydroepiandrosterone (DHEA) on monoamine oxidase (MAO) activity in the corpus striatum (CS) and the nucleus accumbens (NAc) in vivo and in vitro.


METHODS
Male Wistar rats received an i.p. injection of DHEA (30, 60 and 120mg/kg) and MAO activity was assayed by formation of 4-hydroxyquinoline 2h later. For in vitro studies, DHEA (100nM-1mM) was added to brain tissue homogenates to assay MAO activity.


RESULTS
DHEA significantly reduced (-24%) total MAO activity in the NAc (F=8.5, p<0.001), but not in the CS, at 120mg/kg dose. No significant difference was observed when MAO A and MAO B activities were independently analyzed. When assayed in vitro, total MAO, MAO A and MAO B activities were reduced by DHEA to 55.7, 28.2 and 54.4% in the NAc and to 71.9, 44.2 and 61.2% in the CS, respectively (IC(50) 4.7-56.1microM).


CONCLUSIONS
An inhibitory effect of DHEA on MAO activity may be involved in the antidepressant and neuroprotective effects of the steroid. Since MAO inhibition reduces neurodegeneration in clinical trials for Parkinson's disease, our results suggest that DHEA may be useful to treat depression and to prevent neuronal death in this disorder.
Pérez-Neri
Iván
I
Department of Neurochemistry, National Institute of Neurology and Neurosurgery, Insurgentes Sur 3877, Mexico City, Mexico.
Montes
Sergio
S
Ríos
Camilo
C
D000818:Animals; D003342:Corpus Striatum / Q000187:drug effects / Q000201:enzymology*; D003687:Dehydroepiandrosterone / Q000494:pharmacology*; D004305:Dose-Response Relationship, Drug; D004791:Enzyme Inhibitors / Q000494:pharmacology*; D066298:In Vitro Techniques; D007527:Isoenzymes / Q000378:metabolism; D008297:Male; D008995:Monoamine Oxidase / Q000378:metabolism*; D009714:Nucleus Accumbens / Q000187:drug effects / Q000201:enzymology*; D051381:Rats; D017208:Rats, Wistar
D004791:Enzyme Inhibitors; D007527:Isoenzymes; D003687:Dehydroepiandrosterone; D008995:Monoamine Oxidase