Mode of action of a formulation containing hydrazones and saponins against leishmania spp. Role in mitochondria, proteases and reinfection process.

Toxicity and poor adherence to treatment that favors the generation of resistance in the Leishmania parasites highlight the need to develop better alternatives. Here, we evaluated the in vitro effectiveness of hydrazone derived from chromanes 2-(2,3-dihydro-4H-1-benzothiopyran-4-ylidene) hydrazide (TC1) and 2-(2,3-dihydro-4H-1-benzopyran-4-ylidene) hydrazide (TC2) and the mixture of triterpene saponin hederagenin-3-O-(3,4-O-diacetyl-ß-D-xylopyranosyl-(1à3)-a-L- rhamnopyranosyl-(1à2)-a-L-arabinofuranoside, hederagenin-3-O-(3,4-O-diacetyl-a-L- arabinopyranosyl-(1à3)-a-L-rhamnopyranosyl-(1à2)-a-L-arabinofuranoside and, hederagenin-3-O-(4-O-acetyl-ß-D-xylopyranosyl-(1à3)-a-L-rhamnopyranosyl-(1à2)-a-L-arabinofuranoside from Sapindus saponaria (SS) on L. braziliensis and L. pifanoi. Mixtures of TC1 or TC2 with saponin were formulated for topical application and the therapeutic effectiveness was evaluated in the model for cutaneous leishmaniasis (CL) in golden hamster. The mode of action of these compounds was tested on various parasite processes and ultrastructural parasite modifications. TC1, TC2 and SS showed moderate cytotoxicity when tested independently but toxicity was improved when tested in combination. The compounds were more active against intracellular Leishmania amastigotes. In vivo studies showed that combinations of TC1 or TC2 with SS in 1:1 ratio (w/w) cured 100% of hamsters with no signs associated with toxicity. The compounds did cause changes in the mitochondrial activity of the parasite with a decrease in ATP levels and depolarization of membrane potential and overproduction of reactive oxygen species; nevertheless, these effects were not related to alterations in membrane permeability. The phagolysosome ultrastructure was also affected impacting the survival of Leishmania but the function of the lysosome nor the pH inside the phagolysosome did not change. Lastly, there was a protease inhibition which was directly related to the decrease in the ability of Leishmania to infect and multiply inside the macrophage. The results suggest that the combination of TC1 and TC2 with SS in a 1:1 ratio is capable of curing CL in hamsters. This effect may be due to the ability of these compounds to affect parasite survival and the ability to infect new cells.

Exploring Antiparasitic Molecule Sources from Timber by-Product Industries-Leishmanicidal and Trypanocidal Compounds from Clathrotropis brunnea Amshoff.

Through bioguided in vitro assays, the leishmanicidal and trypanocidal effects of an ethanol extract, seven fractions, and two pure substances obtained from Clathrotropis brunnea Amshoff sawdust were established. The effectiveness of the two metabolites was confirmed in a hamster model of cutaneous Leishmaniasis by Leishmania braziliensis and in Balb/c mice infected by Trypanosoma cruzi. In vitro, 3,5-dimethoxystilbene was the most active against L. braziliensis amastigotes, with a median lethal concentration (LC50) of 4.18 µg/ml (17.40 µM) and a selectivity index of 3.55, but showed moderate activity for T. cruzi, with a median effective concentration (EC50) value of 27.7 µg/ml (115.36 µM). Flavanone pinostrobin, meanwhile, showed high activity against L. braziliensis, with an EC50 of 13.61 µg/ml (50.39 µM), as well as for T. cruzi, with an EC50 of 18.2 µg/ml (67.38 µM). The animal model assay of cutaneous Leishmaniasis showed that 50% of the hamsters treated with pinostrobin were definitively cured the cutaneous ulcer, and 40% showed an improvement, with a reduction in the size of the of 84-87%. Moreover, Balb/c mice experimentally infected with T. cruzi and treated for 25 days with pinostrobin experienced a reduction in their parasitemia by 71%. These results demonstrate the high potential of C. brunnea Amshoff against cutaneous Leishmaniasis and American trypanosomiasis and indicate the pharmacological potential of waste from the wood industry, which has tons of potentially useful chemicals for the development of new medicines.

In vivo Antimalarial Activity of α-Mangostin and the New Xanthone δ-Mangostin.

Based on the previously reported in vitro antiplasmodial activity of several xanthones from Garcinia mangostana, two xanthones, α-mangostin and a new compound, δ-mangostin, were isolated from mangosteen husk, and the in vitro antiplasmodial and cytotoxic effects were determined. α-Mangostin was more active against the resistant Plasmodium falciparum chloroquine-resistant (FCR3) strain (IC50 = 0.2 ± 0.01 µM) than δ-mangostin (IC50 = 121.2 ± 1.0 µM). Furthermore, the therapeutic response according to the administration route was evaluated in a Plasmodium berghei malarial murine model. The greatest therapeutic response was obtained with intraperitoneal administration; these xanthones reduced parasitemia by approximately 80% with a daily dose of 100 mg/kg administered twice a day for 7 days of treatment. Neither compound was effective by oral administration. Noticeable toxicological effects were not observed. In addition to the antimalarial effect of these xanthones isolated from G. mangostana husk, the availability of larger amounts of husk raw material to purify the bioactive xanthones is advantageous, permitting additional preclinical assays or chemical transformations to enhance the biological activity of these substances.

Furan type lignans with antimycobacterial activity / Lignanos del tipo furano con actividad antimicobacterial

Compounds such as triclosan, diclofenac and trimetropin posses antibacterial activity, including mycobacterial; their structures are based on two aromatic rings joined by a methylene or a heteroatom. Since a similar structural system is found in natural diarylfuran- based lignans, we studied plants known with this type of lignans, as potential active against Mycobacterium tuberculosis. Fractions of the active extracts were tested for anti-TB activity and their chemical constituents analyzed by NMR spectroscopy. Several extracts and chromatographical fractions exhibited > 90 percent inhibition of M. tuberculosis at 128 ug/mL. Methylpluviatilol, a pure compound isolated from Virola sebifera, was active at this concentration.. These findings suggest that plant species of the families here studied may yield novel lead compounds for the development of antimycobacterial agents.

Compuestos tales como triclosan, diclofenac y trimetoprim poseen actividad antibacterial, incluyendo la antimicobacterial; sus estructuras están basadas en dos anillos aromáticos unidos por un metileno o un heteroátomo. Debido a que en la naturaleza se encuentra un sistema estructural similar del tipo diarilfurano en los lignanos, así como otros subtipos, nosotros estudiamos plantas contra Mycobacterium tuberculosis, de las que se sabe contienen lignanos Las fracciones cromatográficas de los extractos activos fueron ensayadas para actividad anti.Tb y sus constituyentes químicos se analizaron por espectroscopía de RMN. Varios extractos y fracciones cromatográficas exhibieron una inhibición superior al 90 por ciento a 128 ug/mL; el compuesto metilpluviatilol, aislado de mostró una inhibición del 99 por ciento a esa concentración. Esos hechos sugieren que las especies de plantas de las familias aquí estudiadas podrían suministrar nuevos compuestos líderes para el desarrollo de agentes antimicobacteriales.

Leishmanicidal and trypanocidal activity of Sapindus saponaria / Actividad leishmanicida y tripanocida de Sapindus saponaria

Leishmaniasis and trypanosomiasis are parasitic diseases with a high infection rate, being a serious public health issue in the new world. Unfortunately, there are few available commercial drugs, poorly efficient and with increasing parasite resistance. Under these condi- tions, there is a need for new molecules to develop new and better drugs. One approach to carry out this search is using traditional medicine as information source to obtain new molecules or extracts to control these parasite diseases. Sapindus saponaria (Sapindaceae) fruit resin is used in Colombia to treat ulcers caused by Leishmaniasis. In a bioguided study, we have analyzed the in vitro effect of fruit resin, chroma- tographical fractions from fruit resin and also pure compounds against Leishmania species (L. panamensis, L. braziliensis, L. amazonensis and L. donovani) and Trypanosoma cruzi. The in vivo antileishmanial effect was established under the hamster model for cutaneous leish- maniasis by L. panamensis; refined extract of S. saponaria and pure saponins displayed high in vitro and in vivo activity as leishmanicides. In addition, extracts caused low viability on T. cruzi amastigotes. The use of the crude extract can be a good alternative against cutaneous leishmaniasis, due to its activity, reduced hemolytic effect, and easy production procedures.

La Leishmaniasis y la tripanosomiasis son enfermedades parasitarias con una alta incidencia, siendo un serio asunto de salud pública en el nuevo mundo. Desafortunadamente, hay pocas drogas comerciales disponibles, con pobre eficiencia y con una creciente resis- tencia parasitaria. Bajo esas condiciones, se necesitan nuevas moléculas para desarrollar nuevas y mejores drogas. Una aproximación para llevar a cabo esa búsqueda es usar la medicina tradicional como fuente de información para obtener nuevas moléculas o extractos para con- trolar esas enfermedades parasitarias. La resina de Sapindus saponaria (Sapindaceae) se usa en Colombia para tratar úlceras causadas por la Leishmaniasis. En un estudio bioguiado, se analizó el efecto in vitro de varios extractos de la resina, sus fracciones cromatográficas y algu- nos compuestos puros, contra varias especies de Leishmania (L. panamensis, L. braziliensis, L. amazonensis y L. donovani) panamensis y Trypanosoma cruzi. El efecto lesihmanicida in vivo fue establecido usando el modelo en hamster de leishmaniasis cutánea producida por L. panamensis; los extractos refinados de S. saponaria y las saponinas puras mostraron alta actividad in vitro e in vivo como leishmanicidas. Además, los extractos causaron una baja viabilidad en amastigotes de T. cruzi. El uso de extractos refinados en vez de saponinas puras podría ser una buena alternativa contra leishmaniasis cutánea debido a su actividad, poco efecto hemolítico y procedimientos de producción mucho más fáciles.

Comparación de la biodisponibilidad y la farmacocinética entre dos formulaciones de tabletas de metforminade 850 mg en voluntarios colombianos sanos / Bioavalaibility and pharmacokinetic comparison of two formulations of metformin 850 mg tablets in healthy Colombian volunteers

Purpose: The aim of this study was to compare the bioavailability of two formulations of metformin 850 mg tablets: Glucophage® from Merck Santè laboratories (reference product) and Metformin from Winthrop Pharmaceuticals de Colombia SA (test product) in healthy Colombian volunteers.Methods: A random, double blind, two-period, two-week wash out period, crossover study was performed in 24 healthy male and female volunteers for a single 850-mg dose of metformin tablets administrated with 240 ml of water after 12 hours of fasting. Once the drug was administrated, blood samples were collected before and within 24 hour, and plasma metformin concentration was determined by using a validated HPLC method. Pharmacokinetic parameters such as Cmax, AUC0-96h, AUC0-∞, and Tmax were determined. The formulations were considered bioequivalent if the logarithmic mean ratios of ln-transformed Cmax and AUC0-∞ values were within the equivalence range of 80%-125%.Results: ANOVA analysis of the ln-transformed Cmax and AUC0-∞ indicated that none of the effects examined (formulation, period, within and between-subjet variances and carry over) was statistically significant. The mean (±SD) of Cmax 1217.38 (± 251.72) ng/ml vs. 1305.25 (± 301.06) ng/ml, AUC0-96h 1363.49 (± 315.51) ng.h/ml vs. 1584.82 (± 368.75) ng.h/ml, AUC0-∞, 7155.75 (± 1440.74) ng.h/ml vs. 7777.08 (± 1896.49) ng.h/ml, and Tmax 2.57 (± 0.93) h vs. 2.22 (± 0.94) h were obtained with test and reference formulations, respectively. These pharmacokinetic parameters presented differences with the results from other published papers. The 90% confidence interval of the logarithmic ratio of AUC0-∞ and Cmax was within the range of 80-125%.Conclusions: In this study in healthy Colombian volunteers, a single 850-mg dose of metformin tablet test formulation met the criteria for bioequivalence to the reference formulation based on pharmacokinetic parameters AUC0-∞ and Cmax.

Objetivo: El objetivo de este estudio es comparar la bioequivalencia de dos formulaciones de tabletas de metformina de 850 mg: Glucophage® del Laboratorio Merck Santè (producto de referencia) y metformina de Laboratorios Winthrop Pharmaceuticals de Colombia SA (producto de prueba), en voluntarios colombianos sanos.Métodos: Se realizó un estudio aleatorizado, doble ciego, cruzado, en dos períodos y con un tiempo de lavado de dos semanas, en 24 voluntarios sanos, hombres y mujeres, que recibieron una dosis única de metformina de 850 mg, con 240 ml de agua, después de 12 horas de ayuno. Luego de la administración del medicamento, se recolectaron muestras de sangre durante 24 horas y las concentraciones plasmáticas de metformina se determinaron con un método de HPLC validado. Se calcularon los parámetros farmacocinéticos: Cmax, AUC0-96h, AUC0-∞, y Tmax. Las formulaciones se consideraron bioequivalentes si la relación de la media transformada a ln de Cmax y AUC0-∞ estaba dentro del rango de bioequivalencia de 80% a 125%.Resultados: El Anova de los datos transformados a ln de Cmax y AUC0-∞ indicaron que ninguno de los efectos analizados (formulación, período, variación intra e intersujetos y arrastre) fueron estadísticamente significativos. La media (±SD) de los parámetros obtenidos para los productos de prueba y de referencia, respectivamente, fueron: Cmax 1217.38 (± 251.72) ng/ml vs. 1305.25 (± 301.06) ng/ml, AUC0-96h 1363.49 (± 315.51) ng.h/ml vs. 1584.82 (± 368.75) ng.h/ml, AUC0-∞, 7155.75 (± 1440.74) ng.h/ml vs. 7777.08 (± 1896.49) ng.h/ml, and Tmax 2.57 (± 0.93) h vs. 2.22 (± 0.94) h. El intervalo de confianza de la relación logarítmica del AUC0∞ y Cmax se encontró dentro del rango de 80% a 125%.

Chemical composition of ground pearl (Eurhizococcus colombianus) cysts.

Ground pearl (Eurhizococcus colombianus) is a crop pest in Colombia, with special impact on fig, grass, rubus and tomato plants. The insect is resistant to external insecticide application because it produces a thick waxy shell that isolates it from the environment. The composition of this shell was determined by NMR and MS as a triglyceride, whose fatty acid is transformed into other products with the metamorphosis of the insect. Additionally, several enzymatic inhibitors were assayed to control the insect with negative results.

Estudio de bioequivalencia de clonazepam, tabletas de 2 mg, en voluntarios sanos colombianos / Bioequivalence study of clonazepam 2 mg tablets in colombian healthy volunteers

Con el fin de determinar la bioequivalencia de dos formulaciones de tabletas de 2 mg de clonazepam: Sedatril®/Clonazepam MK (Tecnoquímicas S. A., Cali, Colombia) como producto de prueba y Rivotril® (Roche Químicos e Farmacéuticas S. A., Río de Janeiro, Brasil), como producto de referencia, se realizó un estudio de bioequivalencia en 26 voluntarios sanos. Los productos de prueba y de referencia se administraron en condiciones de ayuno de acuerdo con un diseño cruzado aleatorio de dosis única, con dos secuencias, dos tratamientos y un período de lavado de 28 días. Las muestras de sangre se obtuvieron desde las 0 hasta las 96 horas después de la administración del medicamento. Los niveles plasmáticos de clonazepam se determinaron con un método validado por cromatografía líquida de alta eficiencia con detección ultravioleta (HPLC/UV, siglas en inglés). Los parámetros farmacocinéticos ABC0-96, ABC0-∞, Cmax, Tmax, t1/2, and ke se determinaron de los perfiles plasmáticos concentración-tiempo por el método no compartimental. El test de bioequivalencia se realizó con los datos transformados a logaritmo natural (ln) de ABC0-∞ and Cmax. Los intervalos de confianza del 90 por ciento para la relación producto de prueba/producto de referencia fueron de 87,9 por ciento a 103,6 por ciento y 84,4 por ciento a 104,0 por ciento, respectivamente. Estos resultados estuvieron dentro de los rangos de aceptación del 80,0 por ciento al 125 por ciento, establecidos por la FDA y se concluyó que ambos productos son bioequivalentes.

In order to determine the bioequivalence of two formulations of clonazepam 2 mg tablets: Sedatril®/ Clonazepam MK (Tecnoquímicas S. A., Cali, Colombia) as a test product and Rivotril® (Roche Químicos e Farmacêuticas S. A., Rio de Janeiro, Brazil) as a reference product, a bioavailability study was performed in 26 healthy volunteers. Test and reference products were administered under fasting conditions following a single dose, two-sequences, two treatments, crossover randomized design with a 28-day-washout period. Blood samples were obtained from 0 to 96 hours after dosing. Plasma clonazepam levels were determined by a validated high performance liquid chromatography with UV detection method (HPLC/UV). ABC0-96, ABC0-∞, Cmax, Tmax, t1/2, and ke, pharmacokinetic parameters were determined from plasma level-time profiles by a noncompartmental method. ln-trasformed ABC0-∞ and Cmax were tested for bioequivalence. 90%-confidence intervals for test/reference ratio of these parameters were 87.9% to 103.6% and 84.4% to 104.0%, respectively. These results were within the FDA acceptance range of 80% to 125% and it was concluded that both products were bioequivalent.

Biodisponibilidad comparativa entre dos formulaciones de gabapentina cápsulas de 300 mg en voluntarios sanos colombianos / Comparative bio-availability between two formularies of Gabapentine capsules of 300 mg in Colombian volunteers

Introducción: Comparar la biodisponibilidad entre dos productos equivalentes farmacéuticos, permite declarar la bioequivalencia o no de dos medicamentos sometidos a estudio bajo condiciones experimentales similares.Objetivo: Se sometieron a estudio in vivo para determinar la equivalencia biológica, los productos farmacéuticos gabapentina cápsulas de 300 mg, Gabantex®/Gabapentina MK, producto de prueba, de Tecnoquímicas S.A. y Neurontin®, producto de referencia, propiedad de Parke-Davis. Método: El estudio se realizó en 14 voluntarios sanos bajo un diseño aleatorio cruzado, con dosis única. Se administraron 600 mg de cada producto y se tomaron muestras de sangre por un período de 36 horas. Para la determinación de la gabapentina en plasma se aplicó la técnica de cromatografía líquida con detector de fluorescencia. La biodisponibilidad fue comparada para los parámetros farmacocinéticos de área bajo la curva concentración plasmática vs. tiempo (ABC0ºº), concentración máxima (Cmax), el tiempo máximo (Tmax) y la exposición temprana (ABC0Tmax). Resultados: Los intervalos de confianza del 90/100 para el producto de prueba fueron en ABC0ºº 87.5/100-114.5/100, Cmax 85.0-109.7/100 y ABC0Tmax 97.9/100-118.8/100, contenidos en el intervalo de confianza de 80/100-125/100 del producto de referencia. Para el Tmax fue 68.4/100- 94.5/100 que no está contenido en el intervalo de confianza de 80/100 a 120/100 del producto de referencia. Discusión: El parámetro farmacocinético de mayor diferencia en este estudio fue el Tmax para alcanzar la Cmax, diferencia que se explica por factores tales como el origen del principio activo, los excipientes y la tecnología farmacéutica empleada. Conclusiones: Las dos formulaciones son bioequivalentes con respecto al ABC0ºº, Cmax y ABC0Tmax y no bioequivalente con respecto al Tmax, lo cual garantiza que al utilizar el producto de prueba se logrará una respuesta terapéutica similar a la del producto de referencia

Bioequivalencia entre dos formulaciones comerciales de gliclazida en Colombia / Bioequivalence between two commercial formulations of gliclazide in Colombia

Dos formulaciones comerciales de Gliclazida de 80 mg - tabletas, los productos Glidiab de Tecnoquímicas y Diamicron® de Euroetika-Elsevier, fueron sometidos a estudio para evaluar la equivalencia farmacéutica y la equivalencia biológica.Después de comprobar la equivalencia farmacéutica se llevó a cabo el estudio de la equivalencia biológica en 14 voluntarios sanos; la cuantificación de Gliclazida en plasma se realizó por la técnica de cromatografía líquida de alta resolución (HPLC). Los parámetros farmacocinéticos evaluados fueron: área bajo la curva (AUC) de 0-60 horas, concentración máxima (Cmáx) y el tiempo máximo (tmáx) los cuales se analizaron estadísticamente con intervalos de confianza del 90.0 por ciento y un rango de aceptación para bioequivalencia del 80.0 por ciento al 125.0 por ciento para AUC y Cmáx y del 80.0 por ciento al 120.0 por cinto para el tmáx.Ambas formulaciones presentaron alta variabilidad inter e intrasujeto y se encontró que son bioequivalentes con respecto a AUC, pero no lo son con respecto a Cmáx y tmáx

Two commercial formulations of Gliclazide 80 mg tablets were studied in order to evaluate both pharmaceutical and biological equivalence, Glidiab® Tecnoquímicas Laboratories and Diamicron® Euroetika-Elsevier Laboratories. After proving the pharmaceutical equivalence, a bioequivalence was tested in 14 healthy volunteers and the determination of gliclazide in plasma was carried out by high-performance liquid chromatography (HPLC). The evaluated pharmacokinetic parameters were: area under the curve (AUC) from 0 to 60 hours, maximum concentration (Cmax) and time to maximum concentration (Tmax). In statistical analysis the 90.0% confidence intervals for AUC, Cmax and Tmax, and acceptance range for bioequivalence of 80.0%-125.0% to AUC and Cmax and acceptance range of 80:0%-120.0% to Tmax, were applied. Both formulations presented inter and intra subject high variability and it was found that they are bioequivalent in relation to AUC but they are not bioequivalent in relation to Cmax and Tmax

Estudio de bioequivalencia de dos formulaciones de tabletas de carbamazepina de liberación retardada / Study of bioequivalence of two carbamazepine retard-release tablet formulations

En 12 voluntarios sanos se efectuó un estudio de bioequivalencia de dos preparados comerciales de carbamazepina en tabletas de liberación retardada. Este estudio permitió comparar la biodisponibilidad de la formulación de referencia Tegretol® Retard de Ciba Geigy elaborado en Colombia por Novartis, y la formulación de prueba Carbamazepina MK Retard, de Tecnoquímicas.Para evaluar la bioequivalencia se determinaron las curvas de concentración plasmática vs tiempo de las dos formulaciones y se calcularon las áreas bajo la curva (AUC) y las concentraciones máximas (Cmáx).Para la formulación de prueba el intervalo de confianza del 90 por ciento para el AUC estuvo entre 95.7 y 100.7 por ciento y para el C(máx) entre el 88.6 y el 106.1 por ciento. Para ambas determinaciones el rango de aceptación, según normas internacionales, está entre 80 y 125 por ciento de la formulación de referencia. Esto demuestra la bioequivalencia de las dos formulaciones.

A study of the bioequivalence of two comercial carbamazepine retard-release formulations was carried out in 12 healthy volunteers. Studies of bioequivalence allow to compare the bioavailability of the innovator formulation with generic, alternative or branch formulations. In order to evaluate the bioequivalence, plasma carbamazepine concentration/time curves were obtained for the Tegretol® Retard Tablets ­reference formulationand for the test formulation; the area under each curve and the maximum concentration were calculated. After the calculation, statistical analysis of data for the area under the curve of the Carbamazepine Retard Tablets ­test formulation, was between 95.7% and 100.7 % and the maximum concentration of the test formulation was between 88.6% and 106.1%; both parameters with the 90% confidence interval. Since the acceptance range was determined to be between 80.0% and 125.0% of the reference formulation, we concluded from this study that the two formulations are bioequivalent.