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Abstract: Medicinal plants are commonly used in Latin American folk medicine for the treatment of gastric problems. In order to understand the properties of some of their chemical constituents, four natural xanthones, an acetylated derivative, two coumarins (mammea A/BA and mammea C/OA) isolated from Calophyllum brasiliense Cambess and two flavonoids (minimiflorin and mundulin) isolated from Lonchocarpus oaxacensis Pittier, and the chalcone lonchocarpin isolated from Lonchocarpus guatemalensis Benth were tested for their activities on gastric H+,K+-ATPase isolated from dog stomach. All the compounds tested inhibited H+,K+-ATPase activity with varied potency. The xanthones inhibited the H+,K+-ATPase with IC50 values ranging from 47μM to 1.6mM. Coumarins inhibited H+,K+-ATPase with IC50 values of 110 and 638μM. IC50 values for the flavonoids ranged from 9.6 to 510μM among which minimiflorin was the most potent. The results suggest that H+,K+-ATPase is sensitive to inhibition by several types of structurally different natural compounds. The potency of the effects on gastric H+,K+-ATPase depends on the presence, position and number of hydroxyls groups in the molecule. Collectively, these results suggest a potential for important pharmacological and toxicological interactions by these types of natural products at the level of H+,K+-ATPase which may explain, at least in part, the gastroprotective properties, indicated by traditional medicine, of the plants from which these compounds were isolated. [Copyright &y& Elsevier]

Calophyllum brasiliense (Clusiaceae) is a big tree from the Tropical Rain Forests of the American continent. The organic extracts from the leaves yielded coumarins of the mammea type: mammea A/BA, A/BB, B/BA, B/BB, C/OA, C/OB, B/BA cyclo F, B/BB cyclo F, and isomammeigin. The triterpenoids friedelin and canophyllol, as well as the biflavonoid amentoflavone, protocatechuic and shikimic acids, were also obtained. Most of the isolated compounds were tested in vitro against K562, U251, and PC3 human tumor cell lines. The coumarins were cytotoxic against the three cell lines, the highest activity was shown by mammea A/BA (3) (IC50 = 0.04 to 0.59 μM). The mixtures of mammea A/BA (3) + A/BB, mammea B/BA + B/BB and mammea C/OA + C/OB were also highly active (IC50 < 4.05 μM). Friedelin was cytotoxic only against PC3, and U251 lines. Inhibition of HIV-1 reverse transcriptase was also assayed in vitro; however, none of the tested compounds (250 μM) prevented the activity of this enzyme. Most of the isolated compounds were also inactive against fourteen bacterial strains; however mammea A/BA + A/BB, and mammea C/OA + C/OB inhibited the growth of Staphylococcus aureus, S. epidermidis and Bacillus subtilis. [Copyright &y& Elsevier]

Background: The current drugs for Chagas Disease caused by the protozoan Trypanosoma cruzi have limited therapeutic potential and are associated with serious side effects. Natural products can aid to develop new chemotherapeutic agents. Several natural coumarins, especially Mammea A/BA, have shown significant activity against T. cruzi and low toxicity on human lymphocytes, but its effectivity on a wide range of strains need to be tested, as well as to deepen in their mode of action and safety.Hypothesis/purpose: To discern the effects and explore the action mechanisms of mammea A/BA and a mixture of mammea coumarins isolated from Calophyllum brasiliense on Mexican strains of T. cruzi belonging to different genotypes and compare its effectivity with the drug benznidazole.Study Design: We evaluated the trypanocidal activity in vitro of mammea A/BA (93.6%), and a mixture of coumarins, mammea A/BA + A/BB + A/BD (86:10:1%) on Mexican T. cruzi strains belonging to different genotypes Ninoa, Querétaro (TcI) and Ver6 (TcVI).Material and Methods: Mammea A/BA and the mixture of coumarins, were isolated from Calophyllum brasiliense, identified by proton NMR and purity determined by HPLC. The in vitro trypanocidal activity was evaluated on mobility, growth recovery, morphology and infectivity of T. cruzi. The cytotoxicity on mammalian cells was compared with benznidazole. The ultrastructure of the treated epimastigotes was analyzed by transmission electron microscopy (TEM).Results: Mammea A/BA and the mixture of coumarins showed high trypanocidal activity, affecting the mobility, growth recovery, morphology, ultrastructure of epimastigotes, and drastically reduce trypomastigotes infectivity on Vero cells. These substances were four times more potent than benznidazole and showed low cytotoxicity and high selectivity index. The TEM showed severe alterations on the plasmatic membrane, nuclear envelope, as well as, mitochondrial swelling, that leads to the death of parasites.Conclusion: Mammea A/BA (93.6%) and a mixture of mammea A/BA + A/BB and A/BD (86: 10: 1%) isolated from the tropical tree C. brasiliense showed higher trypanocidal activity than the current drug benznidazole on three Mexican strains of T. cruzi. These compounds induced severe physiological and morphological alterations. These results suggest their possible use in preclinical studies. [ABSTRACT FROM AUTHOR]

Abstract We report the effect of the Sesquiterpene Lactones Ambrosin, Incomptine B and Glaucolide E against seven strains of Trypanosoma cruzi , the etiological agent of Chagas Disease. These compounds were isolated from Parthenium hysterophorus , Decachaeta incompta , and Vernonia liatroides , respectively. We evaluated by flow cytometry the viability of epimastigotes. Ambrosin was the most effective, then Incomptine B, and Glaucolide E (IC 50 = 67.1, 123.7, and 215.1 μM, respectively). These compounds were more potent than the drugs Benznidazole (IC 50 > 400 μM) and Nifurtimox (IC 50 = 199.7 to >400 μM). Toxicity to mammalian Vero and Jurkat cells was also determined in vitro. All the compounds had a poor selective index (0.003–1.859). Toxicoinformatics is useful to forecast in silico toxicological and pharmacokinetic properties. Ambrosin and Incomptine B may not possess mutagenic, tumorigenic, or reproductive effects. Glaucolide E could possess a low mutagenic and high tumorigenic effects, and probably target the Amine Oxidase A, Prostaglandin and G/H Synthase I. Interestingly, Ambrosin, Incomptine B and Glaucolide E, comply with Lipinsky Rule of Five, indicating a suitable pharmacokinetic profile. Ambrosin and Incomptine B possess high trypanocidal activity, and pharmaceutical properties suitable for development; however, their safety profile should be optimized by structural modifications. Graphical abstract Image 1 Highlights • Sesquiterpene Lactones Ambrosin, Incomptine B and Glaucolide E have trypanocidal activity. • Ambrosin and Incomptine B possess pharmaceutical properties suitable for development. • The safety profile of Ambrosin and Incomptine B should be optimized before their use as novel trypanocidal drugs. [ABSTRACT FROM AUTHOR]

Aims Linalool and β-pinene are two volatile monoterpenes that possess antidepressant-like activity. These are components of many aromatic plants used in folk medicine around the world to relieve anxiety and depression. In this contribution, we focused on examining the mechanism of action of these compounds. Main methods We used mice in the forced swimming test (FST) and antagonist drugs (i.p.) to receptors related to the depression process such as 5-HT 1A . To assess the possible contribution of the serotoninergic system, animals were pre-treated with WAY 100635 (a 5-HT 1A receptor antagonist) and PCPA (a serotonin synthesis inhibitor). To assess the participation of the noradrenergic system, the animals were pre-treated with yohimbine (an α 2 receptor antagonist), propranolol (a β receptor antagonist) and neurotoxin DSP-4 (a noradrenergic neurotoxin). In the dopaminergic system, we used SCH23390 (a D 1 receptor antagonist). Key findings WAY 100635 blocked the antidepressant-like effect of linalool and β-pinene. In contrast, pretreatment of mice with PCPA did not modify reductions in the immobility time elicited by the two monoterpenes. The yohimbine modified the effect of linalool on immobility time. Propranolol and neurotoxin DSP-4 reversed the anti-immobility effect of β-pinene; also, SCH23390 blocked the antidepressant-like effect of β-pinene. Significance Our results indicate that linalool and β-pinene produce an antidepressant-like effect through interaction with the monoaminergic system. [ABSTRACT FROM AUTHOR]

Zephyranthes (Amaryllidaceae) is a taxonomically complex genus due to the frequent overlap of interspecific morphological variation. In Mexico, Z. alba and Z. fosteri are herbaceous plants that, when distributed in sympatry, generate individuals with complex patterns of morphological variation, leading to taxonomic confusion. Therefore, it is necessary to first characterize these species in allopatric populations. In this contribution, molecular, morphological, and alkaloid profiles were used to characterize both species in allopatric sites. Our results show that Z. alba and Z. fosteri allopatric populations are two well-defined genetic and morphological groups. Flower-related characters were the ones that best allowed us to distinguish between species. In a similar fashion, the alkaloid profile showed remarkable differences among species: four alkaloids were specific to Z. alba and five to Z. fosteri. Lycorine (43.3-88.8%) and galanthamine (87.7-91.4%) were the most abundant alkaloids for each species, respectively. In conclusion, Z. fosteri and Z. alba exhibit noticeable differences when distributed in allopatry. In addition, Z. fosteri has greater genetic and phenotypic plasticity compared to Z. alba , which could be related to the former's ability to colonize new habitats. Finally, the molecular, genetic and chemical markers developed here will provide a framework to further studies aiming to explore if hybridization among Z. alba and Z. fosteri occurs in sympatric populations. • Differences between Zephyranthes fosteri and Z. alba was determined in allopatric populations. • Z. fosteri and Z. alba are two well-defined genetic groups. •Their alkaloid profile is different between species. •Floral morphological characters allowed a clear distinction between species. [ABSTRACT FROM AUTHOR]

Abstract: Ethnopharmacological relevance: Heteropterys brachiata is a plant species that has been used in traditional Mexican medicine for the treatment of nervous disorders. Aim of the study: To evaluate the anxiolytic, anticonvulsant, antidepressant and sedative effects produced by the methanolic extract of Heteropterys brachiata (HbMeOH) in ICR mice. Additionally, we determine the acute toxicity profiles of the extract and the presence of its main constituents. Material and methods: The neuropharmacological effects of the extract were evaluated using a variety of models, such as the elevated plus maze (EPM), the forced swimming test (FST), the pentobarbital potentiation test (PTBt), pentylenetetrazole-induced seizures test (PTZt), and the open field test (OFT). HPLC was employed for obtention of phytochemical profile. Results: HbMeOH produced a significant antidepressant effect in FST at 500 and 750mg/kg doses, while doses from 500 to 1500mg/kg exhibited a clear dose-dependent anxiolytic activity in EPM. A dose of 500mg/kg showed a significant anticonvulsant activity in PTZt and an absence of sedation effects in PTBt. The main compounds of HbMeOH were chlorogenic acid and chlorogenic acid methyl ester, as well as less abundant terpene-type compounds. Furthermore, the extract was either safe with no deaths in mice treated orally with 2000mg/kg. Conclusions: HbMeOH extract which contains mainly hydroxycinnamic acids and triterpene-type compounds, possesses antidepressant, anxiolytic and anticonvulsive properties and can be considered safe or of low toxicity when orally administrated. These findings lend pharmacological justification to the traditional use of Heteropterys brachiata in the treatment of nervous disorders. [ABSTRACT FROM AUTHOR]

Abstract: Ethnopharmacological relevance: The hypoglycemic effect of root and rhizome aqueous decoction of Psacalium decompositum (Asteraceae), a medicinal herb from Mexico, has been experimentally demonstrated, leading to the identification of several hypoglycemic sesquiterpenoids, such as cacalol, and the mixture of 3-hydroxycacalolide, and epi-3-hydroxycacalolide; however, the mechanism of action of these compounds is unknown. Aim of the study: To establish whether cacalol, cacalone epimer mixture and cacalol acetate may block adenosine triphosphate-sensitive potassium channels (KATP channels) in a similar way to the antidiabetic drug glibenclamide. Materials and methods: Cacalol, cacalone epimer mixture, and cacalol acetate were tested on the diazoxide-induced relaxation of male rat aortic rings precontracted with phenylephrine (3.2×10−6 M). Results: Cacalol (10−5 M), cacalol acetate and the cacalone epimer mixture (10−4 M) inhibited the diazoxide effect, in a similar manner and concentration as glibenclamide (10−5 M). Cacalone epimer mixture exerted this effect in a concentration-dependent manner (P <0.01). Cacalol (10−4 M), irreversibly inhibited the diazoxide-induced relaxation, and displayed activity at a lower concentration (10−5 M) than cacalone epimer mixture and cacalol acetate. Conclusions: These results suggest that the studied compounds block KATP channels in a similar way to glibenclamide in rat aorta. However, controversial data indicate that Psacalium decompositum sesquiterpenoids are less effective than glibenclamide in lowering plasma glucose levels, suggesting that cacalol and cacalone epimer mixture, as well as cacalol acetate, may display a higher affinity to SUR2 subunit of KATP channels in aortic smooth muscle than to SUR1 subunit in pancreatic β-cells. [Copyright &y& Elsevier]

Abstract: Thirty-two extracts from 22 Mexican medicinal plants of 15 different families were assayed to determine their antibacterial activity against Escherichia coli and Staphylococcus aureus. Seventeen plants showed antibacterial activity, while five plants showed no activity against both bacteria. All of the extracts showed higher activity against Staphylococcus aureus (methicillin-sensitive and methicillin-resistant) than against Escherichia coli, except one. Among the plants examined, Bursera simaruba (L.) Sarg. (Burseraceae), Haematoxylum brasiletto H. Karst. (Fabaceae), Calophyllum brasiliense Cambess. (Clusiaceae), and Mammea americana L. (Clusiaceae) were highly active against Staphylococcus aureus. Coumarins (mammea A/BA and mammea A/AA) and xanthones, namely jacareubin and 1,3,5,6-tetrahydroxy-2-(3,3-dimethylallyl) xanthone, were isolated as the principle compounds from the last two plants. [Copyright &y& Elsevier]