Amoebicidal and trichomonicidal capacity of polymeric nanoparticles loaded with extracts of the plants Curcuma longa (Zingiberaceae) and Berberis vulgaris (Berberidaceae) / Capacidad amebicida y tricomonicida de nanopartículas poliméricas cargadas con extractos de las plantas Curcuma longa (Zingiberaceae) y Berberis vulgaris (Berberidaceae)

Abstract Introduction: Pathogenic protozoans, like Entamoeba histolytica and Trichomonas vaginalis, represent a major health problem in tropical countries; and polymeric nanoparticles could be used to apply plant extracts against those parasites. Objective: To test Curcuma longa ethanolic extract and Berberis vulgaris methanolic extracts, and their main constituents, against two species of protozoans. Methods: We tested the extracts, as well as their main constituents, curcumin (Cur) and berberine (Ber), both non-encapsulated and encapsulated in polymeric nanoparticles (NPs), in vitro. We also determined nanoparticle characteristics by photon correlation spectroscopy and scanning electron microscopy, and hemolytic capacity by hemolysis in healthy erythrocytes. Results: C. longa consisted mainly of tannins, phenols, and flavonoids; and B. vulgaris in alkaloids. Encapsulated particles were more effective (P < 0.001); however, curcumin and berberine nanoparticles were the most effective treatments. CurNPs had IC50 values (µg/mL) of 9.48 and 4.25, against E. histolytica and T. vaginalis, respectively, and BerNPs 0.24 and 0.71. The particle size and encapsulation percentage for CurNPs and BerNPs were 66.5 and 73.4 nm, and 83.59 and 76.48 %, respectively. The NPs were spherical and significantly reduced hemolysis when compared to non-encapsulated extracts. Conclusions: NPs represent a useful and novel bioactive compound delivery system for therapy in diseases caused by protozoans.

Resumen Introducción: Los protozoos patógenos, como Entamoeba histolytica y Trichomonas vaginalis, representan un importante problema de salud en los países tropicales; y se podrían usar nanopartículas poliméricas para aplicar extractos de plantas contra esos parásitos. Objetivo: Probar los extractos etanólicos de Curcuma longa y Berberis vulgaris, y sus principales constituyentes, contra dos especies de protozoos. Métodos: Probamos los extractos, así como sus principales constituyentes, curcumina (Cur) y berberina (Ber), tanto no encapsulados como encapsulados en nanopartículas poliméricas (NPs), in vitro. También determinamos las características de las nanopartículas por espectroscopía de correlación de fotones y microscopía electrónica de barrido, y la capacidad hemolítica por hemólisis en eritrocitos sanos. Resultados: C. longa tenía principalmente: taninos, fenoles y flavonoides; y B. vulgaris, alcaloides. Las partículas encapsuladas fueron más efectivas (P < 0.001); sin embargo, las nanopartículas de curcumina y berberina fueron los tratamientos más efectivos. CurNPs tenía valores IC50 (µg/mL) de 9.48 y 4.25, contra E. histolytica y T. vaginalis, respectivamente, y BerNPs 0.24 y 0.71. El tamaño de partícula y el porcentaje de encapsulación para CurNPs y BerNPs fueron: 66.5 y 73.4 nm, y 83.59 y 76.48 %, respectivamente. Los NP son esféricos y redujeron significativamente la hemólisis en comparación con los extractos no encapsulados. Conclusiones: Las NP representan un sistema de administración de compuestos bioactivos útil y novedoso para la terapia enfermedades causadas por protozoos.

Furanocoumarins from Ruta chalepensis with Amebicide Activity.

Entamoeba histolytica (protozoan; family Endomoebidae) is the cause of amoebiasis, a disease related to high morbidity and mortality. Nowadays, this illness is considered a significant public health issue in developing countries. In addition, parasite resistance to conventional medicinal treatment has increased in recent years. Traditional medicine around the world represents a valuable source of alternative treatment for many parasite diseases. In a previous paper, we communicated about the antiprotozoal activity in vitro of the methanolic (MeOH) extract of Ruta chalepensis (Rutaceae) against E. histolytica. The plant is extensively employed in Mexican traditional medicine. The following workup of the MeOH extract of R. chalepensis afforded the furocoumarins rutamarin (1) and chalepin (2), which showed high antiprotozoal activity on Entamoeba histolytica trophozoites employing in vitro tests (IC50 values of 6.52 and 28.95 µg/mL, respectively). Therefore, we offer a full scientific report about the bioguided isolation and the amebicide activity of chalepin and rutamarin.

In Vitro Effect of Methanolic Extract of Argemone mexicana against Trichomonas vaginalis.

Infections caused by Trichomonas vaginalis in humans are one of the main public health problems caused by sexually transmitted diseases. Objective of this study was to evaluate potential biological activity of the medicinal plant Argemone mexicana (Mexican poppy) on T. vaginalis. Methanolic extracts of the stems and leaves of A. mexicana, and different fractions were prepared with solvents of different polarities. The extracts and functional groups were detected containing sterols, triterpenes, quinones, flavonoids and, alkaloids. Extracts from both the stems and leaves of A. mexicana inhibited the growth of T. vaginalis with half-maximal inhibitory concentration value of 70.6 and 67.2 µg/ml, respectively. In the active fractions, the most abundant compounds were berberine and jatrorrhizine, with presumed antiparasitic activity.

Antiprotozoal activity against Entamoeba histolytica of plants used in northeast Mexican traditional medicine. Bioactive compounds from Lippia graveolens and Ruta chalepensis.

Amoebiasis caused by Entamoeba histolytica is associated with high morbidity and mortality is becoming a major public health problem worldwide, especially in developing countries. Because of the side-effects and the resistance that pathogenic protozoa build against the standard antiparasitic drugs, e.g., metronidazole, much recent attention has been paid to plants used in traditional medicine around the world in order to find new antiprotozoal agents. We collected 32 plants used in Northeast Mexican traditional medicine and the methanolic extracts of these species were screened for antiprotozoal activity against E. histolytica trophozoites using in vitro tests. Only 18 extracts showed a significant inhibiting activity and among them six plant extracts showed more than 80% growth inhibition against E. histolytica at a concentration of 150 µg/mL and the IC50 values of these extracts were determined. Lippia graveolens Kunth and Ruta chalepensis Pers. showed the more significant antiprotozoal activity (91.54% and 90.50% growth inhibition at a concentration of 150 µg/mL with IC50 values of 59.14 and 60.07 µg/mL, respectively). Bioassay-guided fractionation of the methanolic extracts from these two plants afforded carvacrol (1) and chalepensin (2), respectively, as bioactive compounds with antiprotozoal activity.

Axenic cultivation and comparative phospholipase A2 activity of Giardia duodenalis in a serum-free medium.

Mammalian serum is essential for the growth of Giardia duodenalis cultivated under axenic conditions. Unfortunately, some factors present in bovine serum used as supplement in the culture medium may inhibit protozoal growth and activity. TYI-33-PACSR is a TYI medium supplemented with a serum replacement (PACSR) made up of Earle's amino acid solution, Diamond's vitamin-tween 80 mixtures and LCR (a lipid-cholesterol - rich mixture). PACSR was previously used in the culture media for axenic cultivation of Entamoeba histolytica and Trichomonas vaginalis. The main objective of this work was to demonstrate that TYI-33-PACSR is useful for axenic cultivation of G. duodenalis. Additionally, the activity of phospholipase A(2) (PLA A(2)) in the sub-cellular vesicular fraction (P30) of G. duodenalis grown in TYI-S-33 and TYI-33-PACSR was compared. All strains of Giardia grown in TYI-33-PACSR reached relative cellular densities of 91 to 95% compared to controls growing in serum-supplemented TYI-S-33 medium. Additionally, PLA A(2) activity was similar in the P30 sub-cellular fraction obtained from trophozoites growing in TYI-S-33 and TYI-33-PACSR. Thus, TYI-33-PACSR could be useful in analyzing the biological properties of G. duodenalis in the absence of serum.