title: Strictosidinic acid, isolated from Psychotria myriantha Mull. Arg. (Rubiaceae), decreases serotonin levels in rat hippocampus.
abstract: Psychotria is a complex genus whose neotropical species are known by the presence of glucosidic monoterpene indole alkaloids. These compounds are able to display a large range of effects on the central nervous system, such as anxiolytic, antidepressant, analgesic, and impairment of learning and memory acquisition. The aims of this study were to investigate the effects displayed by strictosidinic acid, isolated from Psychotria myriantha Mull. Arg. (Rubiaceae) leaves, on monoamine levels in rat hippocampus and on monoamine oxidase activity. A significance (p<0.01) of 83.5% reduction in 5-HT levels was observed after intra-hippocampal injection (20 μg/μl). After treatment by intraperitoneal route (10 mg/kg), a 63.4% reduction in 5-HT levels and a 67.4% reduction in DOPAC values were observed. The results indicate that strictosidinic acid seems to act on 5-HT system in rat hippocampus, possibly inhibiting precursor enzymes of 5-HT biosynthesis. The decrease verified in DOPAC levels suggests a role of strictosidinic acid in the dopaminergic transmission, probably due to an inhibition of monoamine oxidase activity, confirmed by the enzymatic assay, which demonstrated an inhibitory effect on MAO A in rat brain mitochondria.
authors.affiliation: Curso de Farmácia, Universidade Federal do Pampa, Uruguaiana, RS, Brazil.
authors.forename: F M
authors.initials: FM
authors.lastname: Farias
authors.forename: C S
authors.initials: CS
authors.lastname: Passos
authors.forename: M D
authors.initials: MD
authors.lastname: Arbo
authors.forename: D M
authors.initials: DM
authors.lastname: Barros
authors.forename: C
authors.initials: C
authors.lastname: Gottfried
authors.forename: V M
authors.initials: VM
authors.lastname: Steffen
authors.forename: A T
authors.initials: AT
authors.lastname: Henriques
mesh_terms: D015102:3,4-Dihydroxyphenylacetic Acid / Q000378:metabolism*; D000818:Animals; D002243:Carbolines / Q000008:administration & dosage / Q000302:isolation & purification / Q000494:pharmacology*; D006027:Glycosides / Q000008:administration & dosage / Q000302:isolation & purification / Q000494:pharmacology*; D006624:Hippocampus / Q000378:metabolism*; D008297:Male; D008928:Mitochondria / Q000187:drug effects / Q000378:metabolism; D008995:Monoamine Oxidase / Q000378:metabolism*; D008996:Monoamine Oxidase Inhibitors / Q000008:administration & dosage / Q000302:isolation & purification / Q000494:pharmacology; D010936:Plant Extracts / Q000008:administration & dosage / Q000737:chemistry / Q000494:pharmacology*; D018515:Plant Leaves; D032069:Psychotria / Q000737:chemistry*; D051381:Rats; D017208:Rats, Wistar; D012701:Serotonin / Q000096:biosynthesis / Q000378:metabolism*; D012702:Serotonin Antagonists / Q000008:administration & dosage / Q000302:isolation & purification / Q000494:pharmacology
chemical_list: D002243:Carbolines; D006027:Glycosides; D008996:Monoamine Oxidase Inhibitors; D010936:Plant Extracts; D012702:Serotonin Antagonists; C551725:strictosidinic acid; D015102:3,4-Dihydroxyphenylacetic Acid; D012701:Serotonin; D008995:Monoamine Oxidase