RESUMEN
Pulsatilla chinensis is a medicinal root plant that has been used to treat a wide range of disease conditions. Our study determined the antiprotozoal activity of various P. chinensis extracts and fractions against Giardia intestinalis including their effects on parasite growth, cell viability, adherence, and morphology. Ethyl acetate extracts (IC50 = 257.081 µg/ml) were the most active to inhibit the growth of G. intestinalis followed by aqueous extract (PWE), saponins, and n-butanol extract. The PWE and ethyl acetate extract inhibited G. intestinalis trophozoites adherence after 3 h of incubation and killed almost 50 % of the parasite population in a time-dependent manner. Changes in morphology, presence of precipitates in the cytoplasm, dissolved cytoplasm with large vacuole, break of flagella and ventral disk, membrane blebs, and intracellular and nuclear clearance of the treated trophozoites were observed by scanning and transmission electron microscopy. We demonstrated that P. chinensis induced these changes in G. intestinalis morphology and consequently has potential therapeutic use against giardiasis.
Asunto(s)
Antiprotozoarios/farmacología , Giardia lamblia/efectos de los fármacos , Extractos Vegetales/farmacología , Pulsatilla/química , Animales , Antiprotozoarios/aislamiento & purificación , Supervivencia Celular/efectos de los fármacos , Giardia lamblia/crecimiento & desarrollo , Giardia lamblia/ultraestructura , Concentración 50 Inhibidora , Microscopía Electrónica de Rastreo , Microscopía Electrónica de Transmisión , Orgánulos/efectos de los fármacos , Orgánulos/ultraestructura , Extractos Vegetales/aislamiento & purificación , Trofozoítos/efectos de los fármacos , Trofozoítos/crecimiento & desarrollo , Trofozoítos/ultraestructuraRESUMEN
A novel strategy was developed to prepare nanospheres and vesicles as drug carriers. The drug-loaded pectin nanospheres and vesicles were fabricated in aqueous media containing Ca2+ and CO3(2-) ions under very mild conditions, which did not involve any surfactant. Through adjusting the preparation conditions, nanosized drug delivery systems with diverse morphologies, that is, nanospheres and vesicles, could be obtained. This technique could offer good control over the morphology and the size of nanospheres and vesicles. The morphologies of the aggregates were observed by environmental scanning electron microscopy and transmission electron microscopy. 5-Fluorouracil (5-FU), an antineoplastic drug, was encapsulated in the nanospheres and vesicles, and the in vitro drug release at different pH values was investigated. With the presence of Ca2+ and CO3(2-) ions in the pectin-based nanospheres/vesicles, the release of the low molecular weight drug could be effectively sustained from the highly hydrolyzed polysaccharide-based drug delivery systems.