Tagetes lucida Cav.: Ethnobotany, phytochemistry and pharmacology of its tranquilizing properties.

ETHNOPHARMACOLOGICAL RELEVANCE: Morelos State is one of the most important regions of Mexico where several plant species are used in traditional medicine to influence central nervous system (CNS) activity; for example Tagetes lucida Cav. AIM OF THE STUDY: To investigate the ethnobotany, phytochemistry and pharmacology of the tranquilizing properties of T. lucida aerial parts. MATERIAL AND METHODS: Data on the medicinal uses of T. lucida were explored by interviewing healers and merchants of local markets in different regions of Morelos State by using a questionnaire. Anxiolytic and/or sedative-like responses of the T. lucida were investigated in experimental models in mice such as: open-field, exploration cylinder, hole-board, plus-maze, and the barbituric-induced hypnosis potentiation. The possible mechanism of action was explored in the presence of WAY100635 (0.32mg/kg, i.p.) and flumazenil (10mg/kg, i.p.) antagonists. A feasible active compound was isolated and identified by using conventional chromatography, including UHPLC and MS (DART) [M+H]+ techniques. RESULTS: Interviews of healers and merchants from ten local regions of Morelos State showed that they recommended T. lucida as infusion and as tincture for several culture-bound syndromes associated with the CNS. Anxiolytic and sedative-like activities of polar extracts were corroborated in the experimental models; these effects were inhibited in the presence of 5-HT1A and GABA/BDZ receptor antagonists. Dimethylfraxetin was identified as one possible active compound. CONCLUSIONS: The results support the anxiolytic and sedative-like properties of T. lucida in traditional medicine by involving serotonergic and GABAergic neurotransmission and coumarinic constituents.

Sedative and anxiolytic efficacy of Tilia americana var. mexicana inflorescences used traditionally by communities of State of Michoacan, Mexico.

AIM OF THE STUDY: Increasing demand of herbal products acquired in stores and markets, as well as medicinal plants collected for personal consume are a known modern tendency. In this study, the ethnomedicinal use of Tilia americana var. mexicana inflorescences as sedative and anxiolytic is reinforced by examinating inflorescences used by communities of the State of Michoacan, Mexico. MATERIALS AND METHODS: Experimental mouse models were used to evaluate the sodium pentobarbital (SP)-induced hypnosis potentiation, ambulatory activity, as well as sedative and anti-anxiety responses via oral administration of the aqueous extracts (10, 30 and/or 100 and 300mg/kg). RESULTS: All samples tested produced a lengthening in the time of SP. Moreover, a significant attenuation in the anxiety-response in the plus-maze test and a diminution in both the head dipping response and ambulatory activity were observed resembling the response to diazepam (0.3mg/kg, i.p.). TLC profiles of the samples showed similar pattern of flavonoids; HPLC-DAD exhibited peaks identified as derived of quercetin and kaempferol that may be responsible for the plant activity. CONCLUSIONS: Our results demonstrate that inflorescences of stored specimens obtained from popular local markets show the same effectiveness with regard to sedative and anxiolytic-like actions than freshly collected samples. Since no toxicity was observed through this route of administration (up to 5000mg/kg); therefore, it suggests that this plant is secure when used as tranquilizer in folk medicine.