RESUMEN
Overexpression of aromatase in breast cancer cells may substantially influence its progression and maintenance. In this sense, the inhibition of aromatase is a key target for the treatment of breast cancer in postmenopausal women. Although several flavonoids had already demonstrated the capacity of inhibiting aromatase activity, the role of biflavonoids as aromatase inhibitors is poorly studied. In this work, the biflavonoids isolated from Garcinia gardneriana, morelloflavone (1), Gb-2a (2) and Gb-2a-7-O-glucose (3) were submitted to in vitro assay to evaluate the aromatase modulatory effect. As results, it was demonstrated that all biflavonoids were able to inhibit the enzyme, with IC50 values ranging from 1.35 to 7.67 µM. This demonstrates that biflavonoids are an important source of scaffolds for the development of new aromatase inhibitors, focusing on the development of new anticancer agents.
Asunto(s)
Inhibidores de la Aromatasa/química , Biflavonoides/química , Garcinia/química , Extractos Vegetales/químicaRESUMEN
Phytochemical investigation of the alkaloid extract of Palicourea sessilis by LC-HRMS/MS using molecular networking and an in silico MS/MS fragmentation approach suggested the presence of several new monoterpene indole alkaloids. These compounds were isolated by semipreparative HPLC, and their structures confirmed by means of HRMS, NMR, and ECD measurements as 4-N-methyllyaloside (3), 4-N-methyl-3,4-dehydrostrictosidine (4), 4ß-hydroxyisodolichantoside (6), and 4α-hydroxyisodolichantoside (7), as well as the known alkaloids alline (1), N-methyltryptamine (2), isodolichantoside (5), and 5-oxodolichantoside (8). In addition, the acetylcholinesterase inhibitory activity of the compounds was evaluated up to 50 µM.
Asunto(s)
Inhibidores de la Colinesterasa/aislamiento & purificación , Rubiaceae/química , Alcaloides de Triptamina Secologanina/aislamiento & purificación , Acetilcolinesterasa/efectos de los fármacos , Brasil , Inhibidores de la Colinesterasa/química , Inhibidores de la Colinesterasa/farmacología , Estructura Molecular , Resonancia Magnética Nuclear Biomolecular , Hojas de la Planta/química , Alcaloides de Triptamina Secologanina/química , Triptaminas/químicaRESUMEN
In the present study, the effects were evaluated of alkaloid fractions (AFs) from Psychotria species and correlated genera, Palicourea and Rudgea, on monoamine oxidases (MAOs) and cholinesterases (ChEs). By HPLC-DAD and UPLC-DAD-MS analyses, indole alkaloids (IA) were detected in all AFs. For the Psychotria and Palicourea species, these IA corresponded to tetrahydro-p-carboline alkaloids (THPCA). On the other hand, pyrrolidinoindoline core compounds were observed for Rudgea species. Regarding their pharmacological activities, none of the AFs was able to inhibit AChE. However, the BChE activity was impaired by the Psychotria and Palicourea AFs. In addition, MAO-A was inhibited by both AFs, but only Psychotria nemorosa AF was able to inhibit significantly MAO-B. Rudgea AFs demonstrated a poor inhibitory profile on MAO-A. Taken together, our results highlighted the Psychotria and Palicourea genera as important sources of scaffolds for the development of MAO-A and BChE inhibitors aiming at the treatment of neurodegenerative and neuropsychiatric diseases.
Asunto(s)
Alcaloides/farmacología , Inhibidores de la Colinesterasa/farmacología , Inhibidores de la Monoaminooxidasa/farmacología , Psychotria/química , Rubiaceae/química , Alcaloides/aislamiento & purificación , Brasil , Inhibidores de la Colinesterasa/aislamiento & purificación , Colinesterasas , Costa Rica , Indoles/aislamiento & purificación , Indoles/farmacología , Simulación del Acoplamiento Molecular , Monoaminooxidasa , Inhibidores de la Monoaminooxidasa/aislamiento & purificación , Hojas de la Planta/químicaRESUMEN
Species of Acanthamoeba are frequently isolated from distinct environmental sources such as water, soil, dust and air. They are responsible to cause infections and disease in humans and animals. In addition, Acanthamoeba sp. are considered an important reservoir of bacteria, virus and fungi, which act as "Trojan horses" to protect these microorganisms of harsh environmental conditions. In this study, nine Acanthamoeba isolates from bromeliads phylloplane were identified based on the morphology of cyst and trophozoite forms. The genotype level was accessed by the sequence analysis of Acanthamoeba small-subunit rRNA gene. Genotypic characterization grouped five isolates in the genotype T2/T6, three in the T4 genotype and one in the genotype T16. The results obtained indicate that the genotype T2/T6 is common on phylloplane. To predict the pathogenic potential of the Acanthamoeba isolates, thermo and osmotolerance assays were employed, although all isolates were capable of surviving at temperatures of 37°C, other tests will be conducted in the future to determine the potential pathogenic of the isolates. Altogether, our results revealed the importance of the presence of Acanthamoeba associated with bromeliads in Rio Grande do Sul, Brazil, and the necessity for further studies to determine the environmental distribution and the role of these species.