title: Monoamine reuptake inhibition and mood-enhancing potential of a specified oregano extract.
abstract: A healthy, balanced diet is essential for both physical and mental well-being. Such a diet must include an adequate intake of micronutrients, essential fatty acids, amino acids and antioxidants. The monoamine neurotransmitters, serotonin, dopamine and noradrenaline, are derived from dietary amino acids and are involved in the modulation of mood, anxiety, cognition, sleep regulation and appetite. The capacity of nutritional interventions to elevate brain monoamine concentrations and, as a consequence, with the potential for mood enhancement, has not been extensively evaluated. The present study investigated an extract from oregano leaves, with a specified range of active constituents, identified via an unbiased, high-throughput screening programme. The oregano extract was demonstrated to inhibit the reuptake and degradation of the monoamine neurotransmitters in a dose-dependent manner, and microdialysis experiments in rats revealed an elevation of extracellular serotonin levels in the brain. Furthermore, following administration of oregano extract, behavioural responses were observed in mice that parallel the beneficial effects exhibited by monoamine-enhancing compounds when used in human subjects. In conclusion, these data show that an extract prepared from leaves of oregano, a major constituent of the Mediterranean diet, is brain-active, with moderate triple reuptake inhibitory activity, and exhibits positive behavioural effects in animal models. We postulate that such an extract may be effective in enhancing mental well-being in humans.
authors.affiliation: DSM Nutritional Products Limited, Research and Development Human Nutrition and Health, PO Box 2676, CH-4002 Basel, Switzerland. annismechan@mac.com
authors.forename: Annis O
authors.initials: AO
authors.lastname: Mechan
authors.forename: Ann
authors.initials: A
authors.lastname: Fowler
authors.forename: Nicole
authors.initials: N
authors.lastname: Seifert
authors.forename: Henry
authors.initials: H
authors.lastname: Rieger
authors.forename: Tina
authors.initials: T
authors.lastname: Wöhrle
authors.forename: Stéphane
authors.initials: S
authors.lastname: Etheve
authors.forename: Adrian
authors.initials: A
authors.lastname: Wyss
authors.forename: Göde
authors.initials: G
authors.lastname: Schüler
authors.forename: Biagio
authors.initials: B
authors.lastname: Colletto
authors.forename: Claus
authors.initials: C
authors.lastname: Kilpert
authors.forename: James
authors.initials: J
authors.lastname: Aston
authors.forename: J Martin
authors.initials: JM
authors.lastname: Elliott
authors.forename: Regina
authors.initials: R
authors.lastname: Goralczyk
authors.forename: M Hasan
authors.initials: MH
authors.lastname: Mohajeri
mesh_terms: D000818:Animals; D014151:Anti-Anxiety Agents / Q000737:chemistry / Q000378:metabolism / Q000627:therapeutic use*; D000928:Antidepressive Agents / Q000737:chemistry / Q000378:metabolism / Q000627:therapeutic use*; D001007:Anxiety / Q000517:prevention & control; D001522:Behavior, Animal; D016227:Benzoquinones / Q000032:analysis / Q000494:pharmacology; D015306:Biogenic Monoamines / Q000502:physiology*; D001921:Brain / Q000378:metabolism; D000081007:Cymenes; D003863:Depression / Q000517:prevention & control; D019587:Dietary Supplements / Q000032:analysis; D055808:Drug Discovery / Q000379:methods; D057809:HEK293 Cells; D006801:Humans; D008297:Male; D051379:Mice; D008996:Monoamine Oxidase Inhibitors / Q000737:chemistry / Q000378:metabolism / Q000627:therapeutic use; D039821:Monoterpenes / Q000032:analysis / Q000097:blood / Q000494:pharmacology; D014179:Neurotransmitter Uptake Inhibitors / Q000737:chemistry / Q000378:metabolism / Q000494:pharmacology / Q000627:therapeutic use*; D031341:Origanum / Q000737:chemistry*; D010936:Plant Extracts / Q000737:chemistry / Q000378:metabolism / Q000627:therapeutic use*; D018515:Plant Leaves / Q000737:chemistry; D011897:Random Allocation; D051381:Rats; D050486:Serotonin Plasma Membrane Transport Proteins / Q000235:genetics / Q000378:metabolism
chemical_list: D014151:Anti-Anxiety Agents; D000928:Antidepressive Agents; D016227:Benzoquinones; D015306:Biogenic Monoamines; D000081007:Cymenes; D008996:Monoamine Oxidase Inhibitors; D039821:Monoterpenes; D014179:Neurotransmitter Uptake Inhibitors; D010936:Plant Extracts; C493230:SLC6A4 protein, human; D050486:Serotonin Plasma Membrane Transport Proteins; C073316:carvacrol; C003466:thymoquinone