Fatty-Acid-Rich Agave angustifolia Fraction Shows Antiarthritic and Immunomodulatory Effect.

Agave angustifolia is a xerophytic species widely used in Mexico as an ingredient in sweet food and fermented beverages; it is also used in traditional medicine to treat wound pain and rheumatic damage, and as a remedy for psoriasis. Among the various A. angustifolia extracts and extract fractions that have been evaluated for their anti-inflammatory effects, the acetonic extract (AaAc) and its acetonic (F-Ac) and methanolic (F-MeOH) fractions were the most active in a xylene-induced ear edema model in mice, when orally administered. Four fractions resulting from chemically resolving F-Ac (F1-F4) were locally applied to mice with phorbol 12-myristate 13-acetate (TPA)-induced ear inflammation; F1 inhibited inflammation by 70% and was further evaluated in a carrageenan-induced mono-arthritis model. When administered at doses of 12.5, 25, and 50 mg/kg, F1 reduced articular edema and the spleen index. In addition, it modulated spleen and joint cytokine levels and decreased pain. According to a GC-MS analysis, the main components of F1 are fatty-acid derivatives: palmitic acid methyl ester, palmitic acid ethyl ester, octadecenoic acid methyl ester, linoleic acid ethyl ester, and oleic acid ethyl ester.

Antidepressant and anxiolytic compounds isolated from Salvia elegans interact with serotonergic drugs.

Salvia elegans belongs to a genus plants with biological activities in central nervous system. In this work, the purpose was to evaluate the anxiolytic and antidepressant effects of fractions and compounds isolated from S. elegans and its interaction with serotoninergic drugs by using behavioral tests in mice. Fractions from aerial parts of S. elegans were obtained by column chromatography, SeF1, SeF2, SeF3, and SeF4. Each of them was administered to 25 mg/k in ICR mice subject to forced swimming test (FST), or elevated plus maze test (EPM), or open field test (OFT). The most active fractions were chemically separated until compounds, which were analyzed as anxiolytic or antidepressant and the coadministration of these treatments with 5-HT1A and 5-HT2 drugs was measured in the different biological tests. All fractions were anxiolytic and antidepressant, oleanolic acid (OA) was found in SeF2, and from SeF3, a mixture of terpenes was found; a GC-MS analysis confirmed the presence of two main compounds: rosifoliol and agaraspirol (TM, mixture of terpenes). TM (doses-response curve, 0.01, 0.1, 0.5, 1.0, and 2.0 mg/kg) and OA (5 mg/kg) were also evaluated demonstrating an antidepressant and anxiolytic effect, respectively. The combination of TM (0.5 mg/kg) with 8-OH (selective 5-HT1A receptor agonist) induced an increment of antidepressant activity, while with the antagonist WAY-100635, the effect diminished. But with DOI (5-HT1c/5-HT2 receptor agonist), there was no change, and with KET (5-HT2 receptor antagonist), the activity was increased. When OA is co-administered with 8-OH or with DOI, the anxiolytic activity of this terpene, diminished; but with the combination with antagonists, the effect of OA shows no change. TM and OA were antidepressant and anxiolytic, respectively, on mice exposed to different tests, and these are able to interact with serotoninergic drugs.

A mixture of quercetin 4'-O-rhamnoside and isoquercitrin from Tilia americana var. mexicana and its biotransformation products with antidepressant activity in mice.

ETHNOPHARMACOLOGICAL RELEVANCE: The aerial parts of Tilia americana var. mexicana (Malvaceae, formerly Tiliaceae) or "sirimo" are used in Mexican traditional medicine for the relief of mild symptoms of mental stress, commonly referred to as "nerve diseases". Individuals use this plant to fall asleep, to calm states of nervous excitement, headaches, mood disorders, and general discomfort. Recent studies indicated that fractions standardized in their flavonoid content possess antidepressant activity in behavioral assays in mice. The present study aims to focus on the evaluation of the antidepressant effect of the mixture of two flavonoids (FMix), and its interaction with serotonergic drugs. Also, the pharmacological effect of the products of the metabolism of aglycone, quercetin, was evaluated in mice subjected to forced swimming test (FST) and open field test (OFT). MATERIALS AND METHODS: A methanol-soluble extract obtained from leaves of Tilia americana was fractionated in an open column chromatographic separation. One of the fractions contained FMix wich is constituted of the mixture of quercetin 4'-O-rhamnoside (1, 47%) y isoquercitrin (2, 53%). The mice were divided into the several following groups: FMix (0.01, 0.1, 0.5, 1.0, and 2 mg/kg); FMix (1.0 mg/kg) and agonist DOI (2.0 mg/kg); FMix (1.0 mg/kg) and antagonist ketanserin (KET, 0.03 mg/kg) of 5-HT2A receptors; FMix (1.0 mg/kg) and selective agonist 8-OH-DPAT (8-OH, 0.01 mg/kg); FMix (1.0 mg/kg) and antagonist WAY100635 (WAY, 0.5 mg/kg) of 5HT1 receptors; Phloroglucinol (PHL); 3,4-dihydroxy-phenyl acid (DOPAC); p-hydroxyphenyl acetic acid (p-HPAA); and m-hydroxyphenyl acetic acid (m-HPAA) were tested in FST or OFT. RESULTS: FMix induced dependent-dose antidepressant activity and, at the highest dose administered, a sedative effect was also observed. The 8-OH-DPAT, or the DOI, or the KET combination with FMix (1.0 mg/kg) induced a higher antidepressant effect than compounds alone; there was no effect exerted with WAY. The activity on OFT increased only with the FMix and KET combination. At the same time, the products of the aglycone metabolism of quercetin, that is, DOPAC and p-HPAA, decreased the immobility time of the mice in FST at 1.0 mg/kg, and a dose-curve was formed for these. CONCLUSION: The antidepressant effect of FMix could depend, at least in part, on the degradation products of quercetin and with a possible action mode through interaction with the serotoninergic system.

Anti-arthritic and anti- inflammatory effects of extract and fractions of Malva parviflora in a mono- arthritis model induced with kaolin/carrageenan.

Malva parviflora is used as food in the gastronomy of some regions of Mexico and, also, in Mexican traditional medicine for inflammation-related conditions like rheumatoid arthritis. The objective of this work was to evaluate its antiarthritic activity in a mice model. In ICR, female mice were tested the dichloromethane extract (MpD) and fractions MpF4 (extracted with a dichoromethane:methanol system) and MpFphy (a precipitate by acetone:methanol) by using the mono-arthritis with kaolin/carrageenan model. During the treatment, joint inflammation was measured daily, and hyperalgesia was measured using the hot plate test. The treatments diminished both joint inflammation and pain. At the end of the evaluation, the left joint and spleen were extracted for determination of pro- and anti-inflammatory cytokines. The results showed that the MpD, MpF4, and MpFphy treatments modulated the concentration of these proteins. Specifically, MpFphy at 1.0 mg/kg increased IL-4 and IL-10 and decreased IL-17, IL-1ß, and TNF-α. GC-MS analysis showed that MpF4 contained a mixture of a total of nine compounds, three of them newly reported for the species. The studies confirmed the presence of five sterols in the MpFphy fraction, including stigmasterol and ß-sitosterol. These results confirm the anti-rheumatoid and anti-inflammatory activities of a fraction rich in sterols from Malva parviflora. Graphical abstract.

Effect of Standardized Fractions and Tiliroside from Leaves of Tilia americana on Depression Tests in Mice.

Depression affects more than 300 million people worldwide, represents one of the leading causes of disability worldwide. Depression treatment is based on the use of tricyclic antidepressants, selective serotonin reuptake inhibitors. These drugs, although clinically effective, have also been shown to have delayed onset activity and produce significant adverse side effects. Medicinal plants are presented as a source of study in the search for therapies. This study was aimed to assess the antidepressant effect (on forced swimming test -FST- and tail suspension test -TST-) of different fractions and tiliroside from Tilia americana. The organic fractions (FAC1-1, FAC1-2) and aqueous fractions (FAqC2-1, FAqC2-3) were obtained by column chromatography and the HPLC analysis allowed the standardization based on the concentration (mg/g) of several compounds: FAqC2-1 with tiliroside 20, quercitrin 41.7, and quercetin glucoside 73.8; FAqC2-3 with tiliroside 2.4, quercitrin 16.6 and 7-O-luteolin glucoside 35.9; FAC1-1 caffeic acid was quantified with 7.87 ; FAC1-2 with tiliroside 24.7 and quercitrin 19.8. Each fraction was tested in ICR mice at different dose in the FST and TST, as well as in the open field test (OFT); tiliroside was isolated and tested in such assays (at 0.05, 0.1, 0.5, and 1.0 mg/kg). All fractions were active, the better was FAC1-2, and induced a dose-dependent effect on FST with an ED50= 2.59 mg/kg and Emax = 175.4 sec; with a sedative effect in OFT. Tiliroside with like-antidepressant activity, showed a dose-response behavior (ED50= 0.04 mg/kg and Emax = 121.42 sec for FST; ED50= 0.014 mg/kg and Emax = 78.28 sec for TST).