RESUMO
This work aimed to synthesize a novel ß-cyclodextrin derivative, itaconyl-ß-cyclodextrin to evaluate whether albendazole inclusion complexes with the new ß-cyclodextrin derivative-improved albendazole dissolution efficiency and its anthelminthic activity. The new derivative was thoroughly evaluated and characterized, and an average degree of substitution of 1.4 per cyclodextrin molecule was observed. Albendazole:itaconyl-ß-cyclodextrin complexes were prepared by spray drying procedures and investigated using phase solubility diagrams, dissolution efficiency, X-ray diffraction, differential scanning calorimetry, Fourier transform infrared, scanning electronic microscopy, mass spectrometry, and nuclear magnetic resonance spectroscopy. Phase solubility diagrams and mass spectrometry studies showed that the inclusion complex was formed in an equimolar ratio. Stability constant values were 602 M-1 in water, and 149 M-1 in HCl 0.1 N. Nuclear magnetic resonance experiments of the inclusion complex showed correlation signals between the aromatic and propyl protons of albendazole and the itaconyl-ß-cyclodextrin inner protons. The studies indicated solid structure changes of albendazole included in itaconyl-ß-cyclodextrin. The maximum drug release was reached at 15 min, and the inclusion complex solubility was 88-fold higher than that of the pure drug. The in vitro anthelmintic activity assay showed that the complex was significantly more effective than pure albendazole.
Assuntos
Albendazol/química , Anti-Helmínticos/síntese química , Trichinella spiralis/efeitos dos fármacos , beta-Ciclodextrinas/síntese química , Administração Oral , Animais , Anti-Helmínticos/química , Anti-Helmínticos/farmacologia , Varredura Diferencial de Calorimetria , Desenho de Fármacos , Microscopia Eletrônica de Varredura , Estrutura Molecular , Solubilidade , beta-Ciclodextrinas/química , beta-Ciclodextrinas/farmacologiaRESUMO
The oral route has notable advantages to administering dosage forms. One of the most important questions to solve is the poor solubility of most drugs which produces low bioavailability and delivery problems, a major challenge for the pharmaceutical industry. Albendazole is a benzimidazole carbamate extensively used in oral chemotherapy against intestinal parasites, due to its extended spectrum activity and low cost. Nevertheless, the main disadvantage is the poor bioavailability due to its very low solubility in water. The main objective of this study was to prepare microcrystal formulations by the bottom-up technology to increase albendazole dissolution rate, in order to enhance its antiparasitic activity. Thus, 20 novel microstructures based on chitosan, cellulose derivatives, and poloxamer as a surfactant were produced and characterized by their physicochemical properties and in vitro biological activity. To determine the significance of type and concentration of polymer, and presence or absence of surfactant in the crystals, the variables area under the curve, albendazole microcrystal solubility, and drug released (%) at 30 min were analyzed with a three-way ANOVA. This analysis indicated that the microcrystals made with hydroxyethylcellulose or chitosan appear to be the best options to optimize oral absorption of the active pharmaceutical ingredient. The in vitro evaluation of anthelmintic activity on adult forms of Trichinella spiralis identified system S10A as the most effective, of choice for testing therapeutic efficacy in vivo.
Assuntos
Albendazol , Trichinella spiralis/efeitos dos fármacos , Triquinelose/tratamento farmacológico , Administração Oral , Albendazol/administração & dosagem , Albendazol/farmacocinética , Animais , Anti-Helmínticos/administração & dosagem , Anti-Helmínticos/farmacocinética , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Disponibilidade Biológica , Celulose/análogos & derivados , Celulose/química , Celulose/farmacologia , Quitosana/química , Quitosana/farmacologia , Sistemas de Liberação de Medicamentos , SolubilidadeRESUMO
Trichinellosis is a serious disease with no satisfactory treatment. We aimed to assess the effect of myrrh (Commiphora molmol) and, for the first time, thyme (Thymus vulgaris L.) against enteral and encysted (parenteral) phases of Trichinella spiralis in mice compared with albendazole, and detect their effect on inducible nitric oxide synthase (iNOS) expression. Oral administration of 500 mg/kg of myrrh and thyme led to adult reduction (90.9%, 79.4%), while 1,000 mg/kg led to larvae reduction (79.6%, 71.3%), respectively. Administration of 50 mg/kg of albendazole resulted in adult and larvae reduction (94.2%, 90.9%). Positive immunostaining of inflammatory cells infiltrating intestinal mucosa and submucosa of all treated groups was detected. Myrrh-treated mice showed the highest iNOS expression followed by albendazole, then thyme. On the other hand, both myrrh and thyme-treated groups showed stronger iNOS expression of inflammatory cells infiltrating and surrounding encapsulated T. spiralis larvae than albendazole treated group. In conclusion, myrrh and thyme extracts are highly effective against both phases of T. spiralis and showed strong iNOS expressions, especially myrrh which could be a promising alternative drug. This experiment provides a basis for further exploration of this plant by isolation and retesting the active principles of both extracts against different stages of T. spiralis.
Assuntos
Antinematódeos/farmacologia , Óxido Nítrico Sintase Tipo II/metabolismo , Terpenos/farmacologia , Thymus (Planta) , Trichinella spiralis/efeitos dos fármacos , Albendazol/farmacologia , Animais , Linhagem Celular , Commiphora/química , Fibroblastos/efeitos dos fármacos , Imuno-Histoquímica , Intestino Delgado/parasitologia , Larva/efeitos dos fármacos , Camundongos Endogâmicos BALB C , Músculo Esquelético/parasitologia , Trichinella spiralis/enzimologiaRESUMO
Trichinellosis is a serious disease with no satisfactory treatment. We aimed to assess the effect of myrrh (Commiphora molmol) and, for the first time, thyme (Thymus vulgaris L.) against enteral and encysted (parenteral) phases of Trichinella spiralis in mice compared with albendazole, and detect their effect on inducible nitric oxide synthase (iNOS) expression. Oral administration of 500 mg/kg of myrrh and thyme led to adult reduction (90.9%, 79.4%), while 1,000 mg/kg led to larvae reduction (79.6%, 71.3%), respectively. Administration of 50 mg/kg of albendazole resulted in adult and larvae reduction (94.2%, 90.9%). Positive immunostaining of inflammatory cells infiltrating intestinal mucosa and submucosa of all treated groups was detected. Myrrh-treated mice showed the highest iNOS expression followed by albendazole, then thyme. On the other hand, both myrrh and thyme-treated groups showed stronger iNOS expression of inflammatory cells infiltrating and surrounding encapsulated T. spiralis larvae than albendazole treated group. In conclusion, myrrh and thyme extracts are highly effective against both phases of T. spiralis and showed strong iNOS expressions, especially myrrh which could be a promising alternative drug. This experiment provides a basis for further exploration of this plant by isolation and retesting the active principles of both extracts against different stages of T. spiralis.
Assuntos
Animais , Antinematódeos/farmacologia , Óxido Nítrico Sintase Tipo II/metabolismo , Thymus (Planta) , Terpenos/farmacologia , Trichinella spiralis/efeitos dos fármacos , Albendazol/farmacologia , Linhagem Celular , Commiphora/química , Fibroblastos/efeitos dos fármacos , Imuno-Histoquímica , Intestino Delgado/parasitologia , Larva/efeitos dos fármacos , Camundongos Endogâmicos BALB C , Músculo Esquelético/parasitologia , Trichinella spiralis/enzimologiaRESUMO
Albendazole-ß-cyclodextrin citrate (ABZ:C-ß-CD) inclusion complex in vivo antiparasitic activity was evaluated in the parenteral phase of Trichinella spiralis infection in mice. An equimolar complex of ABZ:C-ß-CD was prepared by spray-drying and tested in CBi-IGE male mice orally infected with L1 infective larvae. Infected animals were treated with 50 or 30mg/kg albendazole, (ABZ) equivalent amounts of the ABZ:C-ß-CD complex and non treated (controls). Mice received a daily dose on days 28, 29 and 30 post-infection. A week later, larval burden and percentage of encysted dead larvae were assessed in the host by counting viable and non-viable larvae in the tongue. Complexation of ABZ with C-ß-CD increased the drug dissolution efficiency nearly eightfold. At 37 days p-i, the reduction percentage in muscle larval load was 35% in mice treated with 50mg/kg/day ABZ and 68% in those given the complex. Treatment with the lower dose showed a similar decrease in parasite burden. Treated animals showed a high percentage of nonviable larvae, the proportion being significantly higher in mice receiving the complex than in control animals (72-88% vs. 11%, P=0.0032). These data indicate that ABZ:C-ß-CD increases bioavailability and effectiveness of ABZ against encapsulated Trichinella larvae, thus allowing the use of small doses.
Assuntos
Albendazol/química , Albendazol/farmacologia , Antiparasitários/química , Antiparasitários/farmacologia , Ácido Cítrico/química , Trichinella spiralis/efeitos dos fármacos , beta-Ciclodextrinas/química , Animais , Masculino , Camundongos , Trichinella spiralis/fisiologiaRESUMO
Trichinellosis is a zoonotic disease affecting people all over the world, for which there is no speedy and reliable treatment. Albendazole (ABZ), an inexpensive benzimidazole used in oral chemotherapy against helminthic diseases, has a broad spectrum activity and is well tolerated. However, the low absorption and variable bioavailability of the drug due to its low aqueous solubility are serious disadvantages for a successful therapy. In this study, we evaluated the in vivo antiparasitic activity of three novel solid microencapsulated formulations, designed to improve ABZ dissolution rate, in a murine model of trichinellosis. Both ABZ and the microparticulate formulations were administered during the intestinal phase of the parasite cycle, on days 5 and 6 post-infection. This protocol significantly decreased muscle larval burden measured in the parenteral phase, on day 30 post-infection, when compared with the untreated control. Moreover, two of the three microencapsulated formulations both strongly and consistently reduced worm burden.
Assuntos
Albendazol/administração & dosagem , Anti-Helmínticos/administração & dosagem , Trichinella spiralis/efeitos dos fármacos , Triquinelose/tratamento farmacológico , Albendazol/química , Animais , Anti-Helmínticos/química , Química Farmacêutica , Modelos Animais de Doenças , Intestinos/parasitologia , Larva , Masculino , Camundongos , Músculos/parasitologia , Soluções , Triquinelose/parasitologiaRESUMO
Albendazole and mebendazole are widely used in the treatment of trichinellosis; however, chemotherapy failure has been reported. In an effort to develop new anthelminthic compounds, we examined a previously synthesized 2-(trifluoromethyl)-1H-benzimidazole derivative (1) that showed good in vitro activity against Trichinella spiralis muscle larvae but low in vivo efficacy. In order to improve the solubility of compound 1, an inclusion complex with 2-hydroxypropyl-ß-cyclodextrin (1/HP-ßCD) was prepared. When 1/HP-ßCD was tested in vivo, it significantly reduced the ML burden (84%). In addition, a proteomic analysis of T. spiralis ML treated with 1 revealed significant changes in the expression levels of proteins involved in energy metabolism and the cytoskeleton of the parasite. Compound (1) also induced extensive ultrastructural changes in the cuticle, hypodermis and midgut of the parasite.
Assuntos
Anti-Helmínticos/farmacologia , Benzimidazóis/farmacologia , Trichinella spiralis/efeitos dos fármacos , Triquinelose/parasitologia , beta-Ciclodextrinas/farmacologia , 2-Hidroxipropil-beta-Ciclodextrina , Animais , Eletroforese em Gel Bidimensional , Regulação da Expressão Gênica/efeitos dos fármacos , Larva , Espectrometria de Massas , Camundongos , Camundongos Endogâmicos BALB C , Microscopia Eletrônica de Transmissão , Músculos/parasitologia , Proteômica , Trichinella spiralis/ultraestrutura , Triquinelose/tratamento farmacológicoRESUMO
The present study investigates the in vitro efficacy of derivatives of the cyclooctadepsipeptides and the aminophenylamidines, which are promising candidates for the evaluation of the treatment of human soil-transmitted helminthiases. The effects of emodepside and PF1022A as well as of amidantel, deacylated amidantel and tribendimidine were evaluated in a concentration range between 0.01 and 100 µg/ml against third-stage larvae (L3) and adult worms of Nippostrongylus brasiliensis and first-stage larvae (L1) of Trichinella spiralis. Furthermore, drug combinations of PF1022A plus deacylated amidantel or tribendimidine and of tribendimidine plus levamisole were tested for any potential additive or even synergistic interactions. Emodepside had a significantly lower EC(50) value than PF1022A in the T. spiralis (0.02788 vs. 0.05862 µg/ml) and the N. brasiliensis (0.06188 vs. 0.1485 µg/ml) motility assays but not in the acetylcholine esterase secretion assay with adult N. brasiliensis (0.05650 vs. 0.06886 µg/ml). While amidantel showed only minimal or at best partial inhibition of nematode motility and acetylcholine esterase secretion, tribendimidine was nearly as potent as deacylated amidantel. Whereas deacylated amidantel had a significantly lower EC(50) than tribendimidine in the N. brasiliensis L3 motility assay (0.05492 vs. 0.2080 µg/ml), differences were not significant in the T. spiralis L1 motility assay (0.7766 vs. 1.145 µg/ml). Surprisingly, none of the combinations showed improved efficacy when compared to the individual drugs including levamisole/tribendimidine, which have previously been reported to act synergistically against Ancylostoma ceylanicum.
Assuntos
Anti-Helmínticos/farmacologia , Depsipeptídeos/farmacologia , Nippostrongylus/efeitos dos fármacos , Fenilenodiaminas/farmacologia , Trichinella spiralis/efeitos dos fármacos , Animais , Sinergismo Farmacológico , Larva/efeitos dos fármacos , Larva/fisiologia , Locomoção/efeitos dos fármacos , Nippostrongylus/fisiologia , Trichinella spiralis/fisiologiaRESUMO
We evaluated the in vitro effects of estradiol, progesterone, and testosterone on the molting process, which is the initial and crucial step in the development of the muscular larvae (ML or L1) to adult worm. Testosterone had no significative effect on the molting rate of the parasite, however, progesterone decreased the molting rate about a 50% in a concentration- and time-independent pattern, while estradiol had a slight effect (10%). The gene expression of caveolin-1, a specific gene used as a marker of parasite development, showed that progesterone and estradiol downregulated its expression, while protein expression was unaffected. By using flow citometry, a possible protein that is recognized by a commercial antiprogesterone receptor antibody was detected. These findings may have strong implications in the host-parasite coevolution, in the sex-associated susceptibility to this infection and could point out to possibilities to use antihormones to inhibit parasite development.
Assuntos
Expressão Gênica/fisiologia , Hormônios Esteroides Gonadais/metabolismo , Helmintíase/parasitologia , Interações Hospedeiro-Parasita/fisiologia , Muda/fisiologia , Receptores de Progesterona/metabolismo , Trichinella spiralis/crescimento & desenvolvimento , Animais , Caveolina 1/efeitos dos fármacos , Caveolina 1/metabolismo , Regulação para Baixo/efeitos dos fármacos , Estradiol/metabolismo , Estradiol/farmacologia , Feminino , Expressão Gênica/efeitos dos fármacos , Hormônios Esteroides Gonadais/farmacologia , Helmintíase/tratamento farmacológico , Humanos , Larva/efeitos dos fármacos , Larva/crescimento & desenvolvimento , Muda/efeitos dos fármacos , Progesterona/metabolismo , Progesterona/farmacologia , Receptores de Progesterona/efeitos dos fármacos , Testosterona/metabolismo , Testosterona/farmacologia , Trichinella spiralis/efeitos dos fármacosRESUMO
A series of 2-(trifluoromethyl)-1H-benzimidazole derivatives (1a-1i) were synthesized via Phillips cyclocondensation of a substituted 1,2-phenylenediamine and trifluoroacetic acid. The synthesized compounds were evaluated in vitro against various protozoan parasites: Giardia intestinalis, Entamoeba histolytica, Trichomonas vaginalis and Leishmania mexicana, and they showed nanomolar activities against the first three protozoa tested. The compounds were also tested in vitro and in vivo against the nematode Trichinella spiralis. Compounds 1b, 1c and 1e had the most desirable in vitro antiparasitic profile against all parasites studied. In the in vivo model against T. spiralis, compounds 1b and 1e showed good activity against the adult phase at 75 mg/Kg. However, against the muscle larvae stage, only compound 1f exhibited in vivo antiparasitic efficacy.