RESUMO
Huperzine A [Hup A], the alkaloid produced by the Chinese medicinal plant Huperzia serrata, has been documented to be a promising agent for the treatment of Alzheimer's disease due to its potent acetylcholinesterase inhibitory [AChEI] activity. The search for anticholinesterase natural products, as well as for alternative sources of Hup A in Mexican lycopods, prompted us to investigate these plants. The action of methanolic and alkaloidal extracts of three Huperzia species [H. cuernavacensis, H. dichotoma, and H. linifolia] was evaluated using an in vitro anticholinesterase activity assay. Also, chromatographic and spectroscopic analyses were employed to detect the presence of Hup A. Methanolic and alkaloidal extracts of H. cuernavacensis showed IC[50] =5.32+/-0.8micro g/mL and 0.74+/-0.05micro g/mL; H. dichotoma displayed AChEI with IC[50] values =14.11+/-2.1micro g/mL and 0.64+/-0.09micro g/mL; and H. linifolia presented IC[50] =158.37+/-8.7micro g/mL and 4.2+/-1.24micro g/mL, respectively, compared to the control Hup A [IC[50]= 0.16+/-0.03micro g/mL]. Hup A was identified in the extracts of H. dichotoma, but it was not detected in the extracts of H. cuernavacensis and H. linifolia by [1]H NMR techniques. This study reveals H. dichotoma as a new source of Hup A, and presents H. linifolia and H. cuernavacensis as potential candidates to obtain other anticholinesterase compounds useful in the Alzheimer's disease treatment
RESUMO
<p><b>OBJECTIVE</b>To study the effect of crude methanol and n-hexane extracts of Hypericum connatum (H. connatum) and Hypericum caprifoliatum on trophoblast-like cells.</p><p><b>METHODS</b>BeWo and JEG-3 trophoblast-like cells were submitted to different extract concentrations (1, 5, 10 and 15 µg/mL) and evaluated in relation to cell viability and in vitro trophoblast differentiation and function. Cell viability was evaluated using WST-1 reagent. Differentiation was measured by luciferase production, hCG production/release, and mitogen-activated protein kinase signaling pathway activation. The function of the trophoblast-like cells was measured by (45)Ca(2+) influx evaluation.</p><p><b>RESULTS</b>The results showed a decrease in cell viability/proliferation. Both plants and different extracts induced a significant decrease in hCG production/release and luciferase production. H. connatum did not cause mitogen-activated protein kinase signaling pathway disturbance; however, Hypericum caprifoliatum n-hexane extract at 15 µg/mL inhibited extracellular signal-regulated kinase 1/2 activation. The significant increase in Ca(2+) influx by JEG-3 cells was seen after short and long incubation times with H. connatum methanolic extract at 15 µg/mL.</p><p><b>CONCLUSIONS</b>The results indicated that these two Hypericum species extracts can interfere on trophoblast differentiation and Ca(2+) influx, according to their molecular diversity. Although in vivo experiments are necessary to establish their action on placental formation and function, this study suggests that attention must be paid to the potential toxic effect of these plants.</p>
RESUMO
Objective: To study the effect of crude methanol and n-hexane extracts of Hypericum connatum (H. connatum) and Hypericum caprifoliatum on trophoblast-like cells. Methods: BeWo and JEG-3 trophoblast-like cells were submitted to different extract concentrations (1, 5, 10 and 15 μg/mL) and evaluated in relation to cell viability and in vitro trophoblast differentiation and function. Cell viability was evaluated using WST-1 reagent. Differentiation was measured by luciferase production, hCG production/release, and mitogen-activated protein kinase signaling pathway activation. The function of the trophoblast-like cells was measured by