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MAO Inhibitors (mao + inhibitor)
Selected AbstractsBiotransformation of xenobiotics by amine oxidasesFUNDAMENTAL & CLINICAL PHARMACOLOGY, Issue 2 2001Margherita Strolin Benedetti Although the cytochrome P450 (CYP) system ranks first in terms of catalytic versatility and the wide range of xenobiotics it detoxifies or activates to reactive intermediates, the contribution of amine oxidases and in particular of monoamine oxidases (MAOs) to the metabolism of xenobiotics is far from negligible but has been largely neglected. In this review on the involvement of amine oxidases in the metabolism of xenobiotics, the major characteristics reported for the CYP system (protein, reaction, tissue distribution, subcellular localisation, substrates, inhibitors, inducers, genetic polymorphism, impact of different physiopathological conditions on the activity, turnover) will be compared, whenever possible, with the corresponding characteristics of amine oxidases (MAOs in particular). The knowledge of the involvement of MAO-A, -B or both in the metabolism of a drug allows us to predict interactions with selective or non-selective MAO inhibitors (e.g. the metabolism of a drug deaminated by both forms of MAO is not necessarily inhibited in vivo by a selective MAO-A or -B inhibitor). If a drug is metabolized by MAOs, competitive interactions can occur with other drugs that are MAO substrates, e.g. with ,-adrenoceptor agonists and antagonists, prodrugs of dopamine, serotonin 5-HT1 -receptor agonists as well as with primaquine, flurazepam and citalopram. Moreover, the knowledge of the involvement of MAOs in the metabolism of a drug may suggest possible, although not obligatory, interactions with tyramine-containing food or drink, with over the counter medicines sold to relieve the symptoms of coughs and colds (generally containing the indirectly-acting sympathomimetic amine phenylpropanolamine) or with phenylephrine-containing preparations. Finally, biotransformation by amine oxidases, as by CYP, does not always lead to detoxication but can produce toxic compounds. [source] Identification of Kaempferol as a Monoamine Oxidase Inhibitor and Potential Neuroprotectant in Extracts of Ginkgo Biloba LeavesJOURNAL OF PHARMACY AND PHARMACOLOGY: AN INTERNATI ONAL JOURNAL OF PHARMACEUTICAL SCIENCE, Issue 4 2000B. D. SLOLEY The effects of Ginkgo biloba leaf extract on rat brain or livermonoamine oxidase (MAO)-A and -B activity, biogenic amine concentration in nervous tissue, N -methyl- d -aspartate (NMDA)- and N -(2-chloroethyl)- N -ethyl-2-bromobenzylamine (DSP-4)-induced neurotoxicity and antioxidant activity was investigated to determine the effects of the extract on monoamine catabolism and neuroprotection. Ginkgo biloba leaf extract was shown to produce in-vitro inhibition of rat brain MAO-A and -B. The Ginkgo biloba extract was chromatographed on a reverse-phase HPLC system and two of the components isolated were shown to be MAO inhibitors (MAOIs). These MAOIs were identified by high-resolution mass spectrometry as kaempferol and isorhamnetin. Pure kaempferol and a number of related flavonoids were examined as MAOIs in-vitro. Kaempferol, apigenin and chrysin proved to be potent MAOIs, but produced more pronounced inhibition of MAO-A than MAO-B. IC50 (50% inhibition concentration) values for the ability of these three flavones to inhibit MAO-A were 7 times 10,7, 1 times 10,6 and 2 times 10,6m, respectively. Ginkgo biloba leaf extract and kaempferol were found to have no effect ex-vivo on rat or mouse brain MAO or on concentrations of dopamine, noradrenaline, 5-hydroxytryptamine and 5-hydroxyindoleacetic acid. Kaempferol was shown to protect against NMDA-induced neuronal toxicity in-vitro in rat cortical cultures, but did not prevent DSP-4-induced noradrenergic neurotoxicity in an in-vivo model. Both Ginkgo biloba extract and kaempferol were demonstrated to be antioxidants in a lipid-peroxidation assay. This data indicates that the MAO-inhibiting activity of Ginkgo biloba extract is primarily due to the presence of kaempferol. Ginkgo biloba extract has properties indicative of potential neuroprotective ability. [source] Prescribing patterns of antiparkinsonian agents in Europe,MOVEMENT DISORDERS, Issue 8 2010Mário Miguel Rosa MD Abstract In the 1990s, previous knowledge and randomized controlled trials supported the establishment of today's therapeutic recommendations in Parkinson's disease (PD). Scientific evidence allows different options for the treatment of PD. Patterns of use of antiparkinsonian agents (APA) across European countries may thus reflect these options. We wanted to describe patterns of use of APA in Europe and characterize the changes in prescription habits between 2003 and 2007. We investigated APA outpatient sales in 26 European countries where all commercially available APA were studied. Data for molecules and brand names were collected through IMS Health. Treatment per 1000 inhabitants daily (DID) was obtained from the WHO defined daily dose. Prescription pattern changes were evaluated by market share. Prescription patterns varied widely. In most countries, levodopa/dopamine agonists accounted for half of the drug use; whereas in others, anticholinergics, MAO inhibitors and amantadine prevailed. The greatest increase occurred with monoamine oxidase inhibitors and levodopa. There was an increase in dopamine agonists and a decrease in anticholinergics. For a 6.8% dose consume increase, there was a 41.1% sales increase (in euros). We showed an increase in the consumption of APA over 5 years. There was significant heterogeneity in the use of APA in Europe, suggesting differences in drug treatment. Costs of medication increased more than did dose consume, implying an increase in the cost of individual patient treatment. Published evidence does not explain the observed differences in the prescribing of APA. © 2010 Movement Disorder Society [source] Promoting effect and recovery activity from physical stress of the fruit of Morus albaBIOFACTORS, Issue 1-4 2004Keum Hee Hwang Abstract We examined the effects of the fruit of M. alba extracts on the changes of the monoamine oxidase (MAO) activities during and after the physical exercise in rat. Each activity was measured by used serotonin(5-HT) and benzylamine as substrate. Lactate dehydrogenase(LDH) activity and the concentrations of lactate in blood which were clinical indexes of physical exercise were also determined to compare with the relation of MAO activities. Those activities during and after the physical exercise have different tendency in each other enzyme. MAO-A activity was sharply decreased with stress by physical activities compared to the normal group, whereas MAO-B activity was increased for 60 minutes after exercise. All of these indexes were recovered to normal state by oral administration of extract of M. alba. These results of this study suggested M. alba may modulate the MAO activities during exercise and promote the capability of physical activities and show anti-stress effect. In general, MAO inhibitors have been used drugs for the purpose of treatment Parkinson's disease, dementia, deprression. These results can apply to produce the health and functional foods that have modulating effects for these diseases. [source] | ||||||||||