[Effect of Mexican propolis extracts from Apis mellifera on Candida albicans in vitro growth]. / Efecto de extractos de propóleos mexicanos de Apis mellifera sobre el crecimiento in vitro de Candida albicans.

Propolis is a resinous substance collected by bees (Apis mellifera) from different trees and bushes. Due to its antifungal, antibacterial, antiviral and antiparasitic properties, it has continued to be very popular throughout the time showing variable activity depending on its geographical origin. In Mexico, information about this product is very limited. The aim of this work was to evaluate the antifungal activity of four propolis ethanolic extracts from three different Mexican states, and four commercial extracts on Candida albicans growth. A reference strain (ATCC 10231) and 36 clinical isolates of C. albicans were used. The Minimal Inhibitory Concentration (MIC) was determined by the dilution on agar method. Growth curves on Sabouraud Dextrose broth with and without different propolis ethanolic extracts concentrations were performed. In addition, whether the effect was fungistatic or fungicide was determined. The propolis ethanolic extract obtained from Cuautitlán Izcalli, State of Mexico, showed the best biological activity, inhibiting 94.4% from the clinical isolates at 0.8 mg/ml; the reference strain was inhibited at 0.6 mg/ml. The propolis effect was fungistatic in low concentrations and fungicide in concentrations higher to MIC. The Mexican propolis ethanolic extract could be further investigated for its alternative use for the treatment of some C. albicans infections.

Efecto de extractos de propóleos mexicanos de Apis mellifera sobre el crecimiento in vitro de Candida albicans / Effect of Mexican propolis extracts from Apis mellifera on Candida albicans in vitro growth

El propóleos es una sustancia resinosa recolectada por las abejas (Apis mellifera)a partir de diferentes árboles y arbustos. Sus propiedades medicinales hanmantenido su popularidad a través de los años debido a que posee actividadantifúngica, antibacteriana, antiviral y antiparasitaria, mostrando variación en suactividad biológica dependiendo de su origen geográfico. En México, lainformación respecto a la actividad de este producto es muy limitada. El objetivode este trabajo fue evaluar la actividad antifúngica de cuatro extractos etanólicosde propóleos de tres diferentes Estados de la República Mexicana, y de cuatroextractos comerciales sobre el crecimiento de Candida albicans. Se emplearonuna cepa de referencia (ATCC 10231) y 36 aislamientos clínicos de origenhumano de C. albicans. Se determinó la concentración mínima inhibitoria (CMI)por el método de dilución en agar. Se realizaron curvas de crecimiento en caldoglucosado de Sabouraud solo y con diferentes concentraciones de los extractosetanólicos de propóleos; además se determinó si el efecto era fungicida ofungistático. El extracto obtenido en Cuautitlán Izcalli, Estado de Méxicopresentó la mayor actividad biológica, inhibiendo el 94,4% de los aislamientosclínicos a una concentración de 0,8 mg/ml; la cepa de referencia fue inhibida auna concentración de 0,6 mg/ml. El efecto fue fungistático a bajasconcentraciones y fungicida a concentraciones superiores a la CMI. El extractoetanólico de propóleos mexicano podría ser investigado como un tratamientoalternativo en algunas infecciones causadas por C. albicans(AU)

Propolis is a resinous substance collected by bees (Apis mellifera) from differenttrees and bushes. Due to its antifungal, antibacterial, antiviral and antiparasiticproperties, it has continued to be very popular throughout the time showingvariable activity depending on its geographical origin. In Mexico, informationabout this product is very limited. The aim of this work was to evaluate theantifungal activity of four propolis ethanolic extracts from three different Mexicanstates, and four commercial extracts on Candida albicans growth. A referencestrain (ATCC 10231) and 36 clinical isolates of C. albicans were used.The Minimal Inhibitory Concentration (MIC) was determined by the dilution onagar method. Growth curves on Sabouraud Dextrose broth with and withoutdifferent propolis ethanolic extracts concentrations were performed. In addition,whether the effect was fungistatic or fungicide was determined. The propolisethanolic extract obtained from Cuautitlán Izcalli, State of Mexico, showed thebest biological activity, inhibiting 94.4% from the clinical isolates at 0.8 mg/ml;the reference strain was inhibited at 0.6 mg/ml. The propolis effect wasfungistatic in low concentrations and fungicide in concentrations higher to MIC.The Mexican propolis ethanolic extract could be further investigated for itsalternative use for the treatment of some C. albicans infections(AU)

Expanded CTG repeats inhibit neuronal differentiation of the PC12 cell line.

Myotonic dystrophy (DM) is a dominant neuromuscular disorder caused by the expansion of trinucleotide CTG repeats in the 3-untranslated region (3'-UTR) of the MtPK gene. Although DM-associated mental retardation suggests that neuronal functions are disturbed by the expansion mutation, the effect of this alteration in neuronal cells has not been approached. In this study we established stable transfectans of PC12 neuronal cell line expressing the reporter gene CAT alone (empty-vector clone) or fused to the MtPK 3'-UTR with 5, 60, or 90 CTG repeats (CTG5, CTG60, and CTG90 clones, respectively). CTG90 cells exhibited a suppression of NGF-induced neuronal differentiation while empty-vector, CTG5 and CTG60 clones differentiated normally. CTG90 cells displayed normal activation of early differentiation markers, ERK1/2, but the up-regulation of the late marker MAP2 was dramatically reduced. Our neuronal cell system provides the first information of how the mutant MtPK 3'-UTR mRNA affects neuronal functions.