Evaluation of the antischistosomal activity of sulfated α-D-glucan from the lichen Ramalina celastri free and encapsulated into liposomes

The antischistosomal activity of the sulfated polysaccharide α-D-glucan (Glu.SO4) extracted from Ramalina celastri was evaluated after encapsulation into liposomes (Glu.SO4-LIPO) in Schistosoma mansoni-infected mice. The effect of treatment with Glu.SO4 and Glu.SO4-LIPO (10 mg/kg) on egg elimination, worm burden and hepatic granuloma formation was assessed using female albino Swiss mice, 35-40 days of age, weighing 25 ± 2 g, infected with 150 cercariae/animal (Biomphalaria glabrata, BH strain). Four groups (N = 10) were studied, two controls (empty liposomes and NaCl) and two treated groups (Glu.SO4-LIPO and Glu.SO4) using a single dose. Parasitological analysis revealed that Glu.SO4-LIPO was as efficient as Glu.SO4 in reducing egg elimination and worm burden. Treatment with free Glu.SO4 and Glu.SO4-LIPO induced a statistically significant reduction in the number of granulomas (62 and 63 percent, respectively). Lectin histochemistry showed that wheat germ agglutinin intensely stained the egg-granuloma system in all treated groups. On the other hand, peanut agglutinin stained cells in the control groups, but not in the treated groups. The present results suggest a correlation between the decreasing number of hepatic egg-granulomas and the glycosylation profile of the egg-granuloma system in animals treated with free Glu.SO4 or Glu.SO4-LIPO.

Development and in vitro evaluation of biopolymers as a delivery system against periodontopathogen microorganisms

Periodontal disease is the major cause of tooth loss in adults. Porphyromonas gingivalis and Aggregatibacter actinomycetemcomitans are considered key pathogens in periodontitis. The treatment consists of oral hygiene education, instrumentation for removal of calculus (scaling), chemotherapy and periodontal surgery. Several agents are commercially available; these chemicals can alter oral microbiota and have undesirable sideeffects such as vomiting, diarrhea and tooth staining. Hence, the search for alternative products continues and natural phytochemicals isolated from plants used as traditional medicine and the use of biomaterials are considered good alternatives. Chitosan and pullulan are polymers that have been proposed due to their favorable properties such as biocompatibility, biodegradability, and adhesion ability. They can be used as local delivery systems of active principles of plant extracts. Thymus vulgaris, Matricaria chamomilla, Croton lechleri, Calendula officinalis L. and Juliana adstringens Schl. are known to have medicinal activity, and they are used in Mexican traditional medicine. Their extracts were tested in vitro for antimicrobial activity against P. gingivalis and A. actinomycetemcomitans, using agar diffusion and microdilution methods. The antimicrobial activity of films from biopolymers with plant extracts was evaluated by measuring the zones of inhibition against the tested organisms. The aim of this study was to develop bioadhesive films from chitosan and pullulan with added plant extracts and determine the antimicrobial activity of films against periodontal pathogens.

La enfermedad periodontal es la principal causa de perdida de dientes en los adultos. Los agentes causales comunmente identificados con la enfermedad son Porphyromonas gingivalis y Aggregatibacter actinomycetemcomitans. El tratamiento de la enfermedad consiste en educacion sobre higiene oral, remocion de calculos por medio de instrumentacion (raspado y alisado de la raiz), la administracion de medicamentos y cirugia. Hay multiples agentes quimicos disponibles comercialmente; estos pueden alterar la microflora oral y tener efectos secundarios indeseables como vomito, diarrea y pigmentacion dental. Por lo tanto, los productos naturales como los fitoquimicos aislados de plantas que son usadas como medicinas tradicionales y los biomateriales, son considerados buenas alternativas. El quitosan y el pululan son polimeros que han sido propuestos debido a sus propiedades de biocompatibilidad, biodegradabilidad, habilidad de adhesion y que pueden ser usados como sistemas de liberacion de los principios activos de extractos de plantas. Los extractos de Thymus vulgaris, Matricaria chamomilla, Croton lechleri, Calendula officinalis L. y Juliana adstringens Schl. son conocidos por tener actividad medicinal y se usan en la medicina tradicional Mexicana. La actividad antimicrobiana de sus extractos fue probada in vitro contra P. gingivalis y A. actinomycetemcomitans usando los metodos de difusion en agar y de microdilucion. La actividad antimicrobiana de peliculas a base de biopolimeros con extractos de plantas fue evaluada midiendo las zonas de inhibicion de crecimiento de los organismos probados. El proposito de este estudio fue desarrollar peliculas bioadhesivas de quitosan y pululan adicionadas con extractos de plantas y evaluar su actividad antimicrobiana contra periodontopatogenos.

Efecto de un yogur con inulina sobre la función intestinal de sujetos sanos o constipados / Effect of an inulin containing yougurt on intestinal function of healthy and constipated volunteers

The effect of the consumption of a yogurt with 2.36 g inulin and 1.77g polydextrose was evaluated in 33 healthy and 37 constipated adults, compared with the same product without inulin. The study includes two 5-week periods, one with the experimental product and the other with the control product, separated by a three week wash-out. The subjects had to ingest 1 yougurt/day during the first week of each period, 2/day during the third week and 3/day during the fifth week; simultaneously they had to register daily the intensity of the digestive symptoms as well as the frequency and consistency of their stools. The results showed that in healthy subjects, the intake of 2 yogurts with inulin or more per day significantly increased the digestive symptoms (p=0.03), due to a greater emission of rectal gas (p=0.000). Similar findings were observed in the constipated subjects consuming 3 yogurts daily (p=0.0085 y p=0.0048, respectively); stool frequency and consistency were significantly improved in these subjects (p=0.0039 and p=0.014, respectively). These results suggest that the consumption of 2 yogurts with inulin by day help to fight constipation in subjects with this complain while the intake of this same amount may increase discomfort in healthy subjects.

En 33 adultos sanos y 37 constipados se evaluó el efecto del consumo de un yogur que contenía 2.36 g de inulina y 1.77 g de polidextrosa, en comparación con un yogur control sin inulina. El estudio incluyó dos períodos de 5 semanas separados por tres semanas de reposo: uno con el producto experimental y otro con el control. Los sujetos consumieron 1 yogur al día la primera semana de cada período, 2 al día en la tercera y 3 al día en la quinta, y anotaron diariamente la intensidad de los síntomas digestivos así como el número de deposiciones emitidas y su consistencia. Los resultados muestran que a partir de un consumo diario de 2 yogures con inulina existe un aumento significativo de la sintomatología digestiva en los sujetos sanos (p=0.03), debido principalmente a la mayor emisión de gases rectales (p=0.000). Observaciones similares se realizaron en los sujetos constipados con el consumo de 3 productos diarios (p=0.0085 y p=0.0048, respectivamente); sin embargo en aquellos se observó además un mejoramiento significativo tanto en la frecuencia de las deposiciones (p= 0.0039) como en su consistencia (p= 0.014). Este estudio sugiere que el consumo del producto con inulina contribuye a aliviar las molestias de los individuos constipados pero que en los sujetos sanos un consumo de dos yogur al día aumenta los síntomas desagradables.

Potentiation of immune response against malaria in immunocompromised mice through glucan as an immunoadjuvant.

Untreated mice were fully immunocompetent but their treatment with various immunosuppressors rendered them immunocompromised with respect to one or the other or both limbs of immunity. Both, humoral immune response or cell mediated immune response suppressed mice were only partially protected against the challenge with Plasmodium berghei following their immunization. Hydrocortisone treated mice, in which both types of immune responses were suppressed, were not protected against the challenge with P. berghei following their immunization. In contrast, untreated immunized mice, were fully protected against the challenge with P. berghei. The results suggest that glucan potentiated both limbs of immunity and both were involved in the host defence against malaria.