ABSTRACT
BACKGROUND It was previously demonstrated that CMC-20, a nitazoxanide and N-methyl-1H-benzimidazole hybrid molecule, had higher in vitro activity against Giardia intestinalis WB strain than metronidazole and albendazole and similar to nitazoxanide. OBJETIVES To evaluate the in vitro activity of CMC-20 against G. intestinalis strains with different susceptibility/resistance to albendazole and nitazoxanide and evaluate its effect on the distribution of parasite cytoskeletal proteins and its in vivo giardicidal activity. METHODS CMC-20 activity was tested against two isolates from patients with chronic and acute giardiasis, an experimentally induced albendazole resistant strain and a nitazoxanide resistant clinical isolate. CMC-20 effect on the distribution of parasite cytoskeletal proteins was analysed by indirect immunofluorescence and its activity was evaluated in a murine model of giardiasis. FINDINGS CMC-20 showed broad activity against susceptible and resistant strains to albendazole and nitaxozanide. It affected the parasite microtubule reservoir and triggered the parasite encystation. In this process, alpha-7.2 giardin co-localised with CWP-1 protein. CMC-20 reduced the infection time and cyst load in feces of G. muris infected mice similar to albendazole. MAIN CONCLUSIONS The in vitro and in vivo giardicidal activity of CMC-20 suggests its potential use in the treatment of giardiasis.
Subject(s)
Humans , Animals , Mice , Thiazoles/pharmacology , Albendazole/pharmacology , Giardia lamblia/drug effects , Cytoskeletal Proteins/drug effects , Antiprotozoal Agents/pharmacology , Thiazoles/chemistry , Time Factors , Albendazole/chemistry , Fluorescent Antibody Technique, Indirect , Parasitic Sensitivity Tests , Antiprotozoal Agents/chemistryABSTRACT
BACKGROUND It was previously demonstrated that CMC-20, a nitazoxanide and N-methyl-1H-benzimidazole hybrid molecule, had higher in vitro activity against Giardia intestinalis WB strain than metronidazole and albendazole and similar to nitazoxanide. OBJETIVES To evaluate the in vitro activity of CMC-20 against G. intestinalis strains with different susceptibility/resistance to albendazole and nitazoxanide and evaluate its effect on the distribution of parasite cytoskeletal proteins and its in vivo giardicidal activity. METHODS CMC-20 activity was tested against two isolates from patients with chronic and acute giardiasis, an experimentally induced albendazole resistant strain and a nitazoxanide resistant clinical isolate. CMC-20 effect on the distribution of parasite cytoskeletal proteins was analysed by indirect immunofluorescence and its activity was evaluated in a murine model of giardiasis. FINDINGS CMC-20 showed broad activity against susceptible and resistant strains to albendazole and nitaxozanide. It affected the parasite microtubule reservoir and triggered the parasite encystation. In this process, alpha-7.2 giardin co-localised with CWP-1 protein. CMC-20 reduced the infection time and cyst load in feces of G. muris infected mice similar to albendazole. MAIN CONCLUSIONS The in vitro and in vivo giardicidal activity of CMC-20 suggests its potential use in the treatment of giardiasis.
Subject(s)
Humans , Animals , Mice , Thiazoles/pharmacology , Albendazole/pharmacology , Giardia lamblia/drug effects , Cytoskeletal Proteins/drug effects , Antiprotozoal Agents/pharmacology , Thiazoles/chemistry , Time Factors , Albendazole/chemistry , Fluorescent Antibody Technique, Indirect , Parasitic Sensitivity Tests , Antiprotozoal Agents/chemistryABSTRACT
Protease secretion by Giardia duodenalis trophozoites upon interaction with epithelial cells and its association with the parasite adhesion was studied in co-cultures of parasites with IEC6 epithelial cell monolayers in the presence or absence of protease inhibitors. Proteolytic activity in supernatants from trophozoites was enhanced when they were co-cultured with IEC6 cells. This activity was strongly inhibited by pre-incubation of live trophozoites with E-64 and TPCK and a concomitant inhibition of parasite adhesion to IEC6 cells was observed. These data suggest that trophozoites secrete cysteine-type proteases that play a role in the adhesion of G. duodenalis to epithelial cells.
Subject(s)
Animals , Epithelial Cells/enzymology , Giardia/enzymology , Peptide Hydrolases , Protease Inhibitors/pharmacology , Cell Line , Cell Adhesion/drug effects , Cell Communication/drug effects , Giardia/cytology , Peptide Hydrolases/drug effectsABSTRACT
Background. Two albendazole (ABZ) prodrugs, N-methoxycarbonyl-N'-[(2-nitro-4-propylthio) phenyl] thiourea (compound 2), and N-methoxycarbonyl-N'-[2-nitro-5-propylthio) phenyl] thiourea (compound 3) have recently been synthesized. These compounds showed greater solubility than ABZ itself. Methods. In order to evaluate the biotransformation of compounds 2 and 3 to ABZ and/or ABZ-sulphoxide (ABZ-SO), plasma samples taken from mice treated with the prodrugs were analyzed by HPLC. Also, the anthelmintic activity of compounds 2 and 3 against Trichinella spiralis was evaluated in mice experimentally infected with the prarasite. Results. The presence of ABZ and/or ABZ-SO was demostrated in plasma samples taken at different time intervals after prodrug administration, although their levels were low compared to those reached in mice treated with ABZ. Additionally, prodrugs 2 and 3 were also detected in these samples. In regrad to the anthelmintic activity of ABZ prodrugs, it was shown that compound 3 was more active than compound 2. Additionally, it was as effective as ABZ against T. spiralis pre-adult, adult, and female fecundity. However, compound 3 was not as active sa ABZ against the muscle stage of the parasite. Conclusions. Compound 3 had better anthelmintic activity againts T. spiralis than compound 2. The bioconversion of compounds 2 and 3 to ABZ and/or ABZ-SO was demostrated by HPLC, but they did not reach equivalant concentrarion to that of ABZ. Prodrugs 2 and 3 were also present in plasma samples, suggesting that prodrugs were not efficiently reduced in the intestine of mice
Subject(s)
Animals , Male , Female , Mice , Rats , Albendazole/therapeutic use , Anthelmintics/therapeutic use , Rats, Sprague-Dawley , Drug Evaluation, Preclinical , Trichinellosis/drug therapyABSTRACT
La triquinelosis es una zoonosis causada por parásitos del género Trichinella que es trasmitida principalmente por la ingestión de carne de animales como el cerdo, oso y zorro entre otros. Sin embargo, en Europa se han reportado varios brotes debido al comsumo de carne de caballo. La presencia del parásito no ha sido demostrada de manera directa en la carne de estos animales, sin embargo, la identificación de las especies de Trichinella (T. spiralis T. britovi y T. nativa) involucradas en estos brotes ha sido posible a partir de biopsias tomadas de individuos que consumieron carne de caballo. Recientemente, se identificaron por primera vez larvas de T. spiralis en caballos sacrificados en un rastro del Estado de México, presentando así evidencia directa de la infección de estos animales con el parásito. Por otro lado empleando extractos totales o antígenos TSL-1 de T. spiralis se han detectado anticuerpos en contra de Trichinella en caballos sacrificados en rastros de diferentes paises de Europa así como en México. Asimismo, la infección con varias especies de Trichinella se ha logrado reproducir experimentalmente en caballos y los resultados obtenidos son importantes en el desarrollo de métodos de diagnóstico que permitan estimas la prevalencia de esta infección en caballos cuya carne se destina para el consumo tanto animal como humano y eventualmente instrumentar medias para el control de la trasmisión de la triquinelosis por carne de caballos