Nine compounds (MO1–MO9) containing the morpholine moiety were assessed for their inhibitory activities against monoamine oxidases (MAOs) and acetylcholinesterase (AChE). Most of potently inhibited MAO-B; MO1 most with an IC50 value 0.030 µM, followed by MO7 (0.25 µM). MO5 AChE (IC50 = 6.1 µM), MO9 12.01 µM) MAO-A 7.1 was a reversible mixed-type inhibitor MAO-B (Ki 0.018 µM); reversibly competi...

1-Methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) is a potent dopaminergic neurotoxin that causes biochemical, pharmacological, and pathological deficits in experimental animals similar to those seen in human parkinsonian patients. All of the deficits can be prevented by treating mice with selective inhibitors of monoamine oxidase B (MAO-B), including deprenyl, prior to MPTP administration. W...

Inhibitors of monoamine oxidase (MAO) with selectivity and specificity for MAO type B prolong the activity of both endogenously and exogenously derived dopamine, making them an option either as monotherapy in early Parkinson's disease or as adjunctive therapy in patients treated with levodopa who are experiencing motor complications. In addition to symptomatic benefits, experimental data sugges...

A critical problem for developing personalized treatment plans for cognitive disruptions is the lack of understanding how individual differences influence cognition. Recognition memory is one cognitive ability that varies from person to person and that variation may be related to different genetic phenotypes. One gene that may impact recognition memory is the monoamine oxidase A gene (MAO-A), w...

Monoamine oxidase A (MAO-A), the catabolic enzyme of norepinephrine and serotonin, plays a critical role in emotional and social behavior. However, the control and impact of endogenous MAO-A levels in the brain remains unknown. Here we show that the RING finger-type E3 ubiquitin ligase Rines/RNF180 regulates brain MAO-A subset, monoamine levels, and emotional behavior. Rines interacted with MAO...

5-Hydroxyindoleacetic acid (5HIAA) has been shown to be the major metabolite of 5-hydroxytryptamine (serotonin) (1). In man 2 to 8 mg. of the acid are normally excreted in the urine per day (2). This suggests that the major route of metabolism of serotonin proceeds via oxidative deamination, catalyzed, presumably, by monoamine oxidase (MAO). Experiments carried out in vitro (3-6) and in viva de...

In the present study, we evaluated the influence of intraperitoneal administration of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) or 1-methyl-4-phenylpyridinium (MPP(+)) on the placenta. There was no increase in apoptotic cells in the placentas of C57BL/6 mice treated with 25.0 mg/kg MPTP or 17.1 mg/kg MPP(+), indicating that a single injection of the chemicals may induce very slight cy...

BACKGROUND Prior studies report that monoamine oxidases inhibitors (MAO-I) when used as an adjunct to levodopa ameliorate motor symptoms in Parkinson's disease (PD), but this was not tested in relation to cognitive or psychiatric measures. OBJECTIVE Here, we tested the effects of MAO-I as an adjunct to levodopa, in comparison to levodopa or dopamine (DA) agonists alone, on various cognitive, ...

Previous studies of Igaue, Gomes and Yasunobu [l] and Erwin and Hellerman [2] suggested that the liver and kidney monoamine-oxidase (MAO) coenzyme, an FAD derivative, is covalently linked to the protein. Upon hydrolysis it is degraded in consecutive steps to the mononucleotide and the riboflavin-oligopeptide (“MAO-flavin”) level. ESR and absorption spectra of MAO-flavin [3] indicated that the p...

Platelets of healthy subjects and patients suffering from various disorders were assayed for their monoamine oxidase (MAO) activity and protein content. The latter tended to be lower with increasing platelet count. A linear correlation with negative slope between count and protein content was found to exist in platelets obtained from schizophrenic, parkinsonian, and (specific development) dysle...