Artículos y presentaciones en Congresos
URI permanente para esta colección
Examinar
Envíos recientes
- Artículo
Acceso Abierto Evidence of a landlocked reproducing population of the marine pejerrey Odontesthes argentinensis (Actinopterygii; Atherinopsidae)(2019) Colautti, Darío C.; Miranda, Leandro; González-Castro, Mariano; Villanova, Vanina; Strüssmann, Carlos A.; Mancini, Miguel; Maiztegui, Tomás; Berasain, Gustavo; Hattori, Ricardo; Grosman, Fabián; Sanzano, Pablo; Lozano, Ismael; Vegh, Sabina L.; Salinas, Victor; Del Ponti, Omar; Del Fresno, Pamela Sabrina; Minotti, Priscila; Yamamoto, Yoji; Baigún, Claudio R.M.In South America, the order Atheriniformes includes the monophyletic genus<em>Odontesthes</em> with 20 species that inhabit freshwater, estuarine and coastal environments. Pejerrey Odontesthes argentinensis is widely distributed in coastal and estuarineareas of the Atlantic Ocean and is known to foray into estuaries of river systems, particularly in conditions of elevated salinity. However, to our knowledge, a landlockedself-sustaining population has never been recorded. In this study, we examined the pejerrey population of Salada de Pedro Luro Lake (south-east of BuenosAires Province, Argentina) to clarify its taxonomic identity. An integrative taxonomic analysis based on traditional meristic, landmark-based morphometrics and genetictechniques suggests that the Salada de Pedro Luro pejerrey population represents a novel case of physiological and morphological adaptation of a marine pejerrey speciesto a landlocked environment and emphasises the environmental plasticity of this group of fishes - Artículo
Acceso Abierto Akaline, saline and mixed saline-alkaline stresses induce physiological and morfo-anatomical changes in Lotus tenuis shoots(2014) Paz, Rosalía; Reinoso, Herminda; Espasandin, Fabiana; González Antivilo, Francisco; Sansberro, Pedro; Rocco, Rubén; Ruiz, Oscar Adolfo; Menéndez, AnaSaline, alkaline and mixed saline–alkaline conditions frequently co‐occur in soil. In this work, we compared these plant stress sources on the legume Lotus tenuis, regarding their effects on shoot growth and leaf and stem anatomy. In addition, we aimed to gain insight on the plant physiological status of stressed plants. We performed pot experiments with four treatments: control without salt (pH = 5.8; EC = 1.2 dS·m−1) and three stress conditions, saline (100 mm NaCl, pH = 5.8; EC = 11.0 dS·m−1), alkaline (10 mm NaHCO3, pH = 8.0, EC = 1.9 dS·m−1) and mixed salt–alkaline (10 mm NaHCO3 + 100 mm NaCl, pH = 8.0, EC = 11.0 dS·m−1). Neutral and alkaline salts produced a similar level of growth inhibition on L. tenuis shoots, whereas their mixture exacerbated their detrimental effects. Our results showed that none of the analysed morpho‐anatomical parameters categorically differentiated one stress from the other. However, NaCl‐ and NaHCO3‐derived stress could be discriminated to different extents and/or directions of changes in some of the anatomical traits. For example, alkalinity led to increased stomatal opening, unlike NaCl‐treated plants, where a reduction in stomatal aperture was observed. Similarly, plants from the mixed saline–alkaline treatment characteristically lacked palisade mesophyll in their leaves. The stem cross‐section and vessel areas, as well as the number of vascular bundles in the sectioned stem were reduced in all treatments. A rise in the number of vessel elements in the xylem was recorded in NaCl‐treated plants, but not in those treated exclusively with NaHCO3. - Documento de conferencia
Acceso Abierto Vida pampeana: visión integrada del agro-ecosistema pampeano(2018) Garriz, AndrésEl presente proyecto tiene como objetivo general, evaluar las interacciones entre los diversos componentes/actores involucrados en la producción agropecuaria regional y desarrollar protocolos de producción y manejo agropecuario sobre la base de índices modernos de monitoreo, que favorezcan la mitigación de los efectos adversos derivados de las actividades productivas que se desarrollan actualmente. Asimismo, el proyecto busca establecer una plataforma dinámica de evaluaciones y monitoreo de parámetros y prácticas productivas, y simultáneamente, proceder a la identificación y selección de nuevos parámetros que fundamenten el diseño de prácticas agropecuarias amigables con el medio ambiente. - Revisión
Acceso Abierto Protein Palmitoylation and Pathogenesis in Apicomplexan Parasites(2012) Corvi, María Martha; Alonso, Andrés Mariano; Caballero, Marina CeciliaApicomplexan parasites comprise a broad variety of protozoan parasites, including Toxoplasma gondii, Plasmodium, Eimeria, and Cryptosporidium species. Being intracellular parasites, the success in establishing pathogenesis relies in their ability to infect a hostcell and replicate within it. Protein palmitoylation is known to affect many aspects of cell biology. Furthermore, palmitoylation has recently been shown to affect important processes in T. gondii such as replication, invasion, and gliding. Thus, this paper focuses on the importance of protein palmitoylation in the pathogenesis of apicomplexan parasites. - Artículo
Acceso Abierto Sobre ferrocarriles, lagunas y lluvias: características de las pesquerías comerciales de pejerrey en la cuenca del río Salado (provincia de Buenos Aires)(2003) Baigún, Claudio R. M.; Delfino, R. L.La variabilidad hidrológica en lagunas de la pampasia bonaerense es un hecho reconocido desde los tiempos de Florentino Ameghino. Sin embargo, poco se ha explorado como la dinámica hídrica de estos ambientes, directamente vinculada a las precipitaciones, ha estado vinculado al uso de los recursos pesqueros. Asimismo es reconocido que las pesquerías comerciales de pejerrey representaron una actividad de gran importancia durante gran parte del siglo XX. A partir de información histórica (1928-1978) sobre capturas comerciales embarcadas en estaciones correspondientes a los ferrocarriles Roca, San Martín, Sarmiento y Belgrano (incluyendo el inolvidable Midland!), se describen sus características más generales y se analiza su relación con los niveles de precipitación como variable sustitutiva de la superficie de los cuerpos de agua, en diferentes regiones (subcuencas) de la cuenca del Salado. Las mayores capturas en la cuenca provenían de las Encadenadas del Oeste y Encadenadas del Salado. Considerando el total de sitios de embarque se aprecia una elevada variabilidad para toda la cuenca que oscila entre el 10%-180%, estando la media próxima al 100 %. Los ambientes localizados próximos a la desembocadura del río Salado presentaron una menor variación respecto a aquellos situados en la región sudoeste, que poseen una conexión más indirecta con este curso de agua. Asimismo las capturas estuvieron positivamente asociadas con los niveles de lluvia en la mayoría de las subcuencas examinadas, pero con una desfase de 2-3 años. Dicha relación posee importantes implicancias para el manejo de los recursos pesqueros particularmente para la aplicación de medidas regulatorias. Se concluye que los ferrocarriles pampeanos, hoy virtualmente extinguidos, han jugado un papel preponderante en el desarrollo de las pesquerías comerciales del pejerrey hasta la primera mitad del siglo XX. - Artículo
Acceso Abierto Parámetros abióticos y biomasa planctónica en la laguna Chascomús (provincia de Buenos Aires)(2003) Maizels, P.; Etchepare, E.; Chornomaz, E.; Bustingorry, J.; Escaray, R.; Conzonno, Víctor H.La Laguna Chascomús ubicada en la cuenca del Río Salado, es una laguna pampásica de características eutróficas, alcalina y con elevado material en suspensión. En el presente trabajo se presentan datos obtenidos a partir de marzo de 2002, con muestreos semanales en superficie y en la zona pelágica, que permitieron seguir el período de inundación (nivel superior a la cota de 8 metros IGM), que se extendió desde abril a junio y donde el pico máximo alcanzó alrededor de 9 metros. El aporte de agua debido a las precipitaciones se tradujo en un efecto de dilución que determinó que la salinidad disminuyera en un tercio el valor promedio de 1,57 g/l obtenido en el año 2000. Por el contrario los valores de fósforo total (promedio 290 μg P/l) y de nitrógeno total (promedio 880 μg N/l) fueron elevados debido a la influencia de desechos cloacales producto del desborde proveniente de la ciudad y de la planta de tratamientos cloacales que por efecto de la inundación alcanza también la laguna. El seston presentó valores bajos respecto a los usuales (promedio 79,8 mg/l) siendo afectado por el fenómeno de dilución donde de 179 mg/l (máximo) desciende a 25,8 mg/l (mínimo). En correspondencia se registraron mayores valores de lectura del disco de Secchi (promedio 21 cm, rango 12-28 cm). La biomasa algal evaluada en términos de clorofila a, fue elevada (promedio 133,3 μg/l) favorecida no sólo por la elevada concentración de nutrientes sino además por el aumento de la transparencia. La biomasa zooplantónica determinada sobre muestra obtenida por arrastre vertical mediante red de 29 μm y por la suma de la biomasa de copépodos, cladóceros y rotíferos, mostró un promedio de 173 μg/ l y la densidad de 440 individuos/l. Las relaciones entre la biomasa del zooplancton con la clorofila a y con el número de bacterias obtenido por recuento, indicarían que la predación se ejercería tanto sobre organismos autótrofos como heterótrofos. - Artículo
Acceso Abierto New approaches for growth improvement in pejerrey Odontesthes bonariensis (Valenciennes, 1835) culture (Atherinomorpha: Atherinopsidae)(2015) Solimano, Patricio J.; García de Souza, Javier Ricardo; Maiztegui, Tomás; Baigún, Claudio R. M.; Colautti, Darío C.The pejerrey is the most important recreational species in shallow temperate lakes and reservoirs of Argentina and the attempts to develop its culture have started a century ago. A common constraint of pejerrey aquaculture is its poor growth under traditional intensive rearing techniques. The aim of this study was to evaluate the possibility to achieve and maintain high growth rates of pejerrey throughout the rearing process by semi-intensive culture method . Four floating cages were installed in La Salada de Monasterio Lake and each one was stocked with 300 juveniles (10.22 ±0.38cm; 6.52 ±0.82g). From January through March all fish were exposed to natural zooplankton as food source, whereas from April to September two cages were supplied daily with artificial food. The fish exposed to artificial supplementary diets exhibited significantly higher growth (17.5 ±0.98cm; 41.05 ±8.55g) than those in the control cages (15.02 ±0cm ; 23.5 ±0.84g), and exceeded the known values in pejerrey culture. The results suggest that the species potential growth is not fully achieved by common intensive methods and it can be improved by semi-intensive techniques. Accordingly a better understanding of the species nutritional requirements is needed to improve growth rates and enhance pejerrey culture. - Artículo
Acceso Abierto Control of angiogenesis by galectins involves the release of platelet-derived proangiogenic factors(2014) Etulain, Julia; Negrotto, Soledad; Tribulatti, María Virginia; Croci, Diego Omar; Carabelli, Julieta; Campetella, Oscar Eduardo; Rabinovich, Gabriel Adrián; Schattner, Mirta AnaPlatelets contribute to vessel formation through the release of angiogenesis-modulating factors stored in their α-granules. Galectins, a family of lectins that bind β-galactoside residues, are up-regulated in inflammatory and cancerous tissues, trigger platelet activation and mediate vascularization processes. Here we aimed to elucidate whether the release of platelet-derived proangiogenic molecules could represent an alternative mechanism through which galectins promote neovascularization. We show that different members of the galectin family can selectively regulate the release of angiogenic molecules by human platelets. Whereas Galectin (Gal)-1, -3, and -8 triggered vascular endothelial growth factor (VEGF) release, only Gal-8 induced endostatin secretion. Release of VEGF induced by Gal-8 was partially prevented by COX-1, PKC, p38 and Src kinases inhibitors, whereas Gal-1-induced VEGF secretion was inhibited by PKC and ERK blockade, and Gal-3 triggered VEGF release selectively through a PKC-dependent pathway. Regarding endostatin, Gal-8 failed to stimulate its release in the presence of PKC, Src and ERK inhibitors, whereas aspirin or p38 inhibitor had no effect on endostatin release. Despite VEGF or endostatin secretion, platelet releasates generated by stimulation with each galectin stimulated angiogenic responses in vitro including endothelial cell proliferation and tubulogenesis. The platelet angiogenic activity was independent of VEGF and was attributed to the concerted action of other proangiogenic molecules distinctly released by each galectin. Thus, secretion of platelet-derived angiogenic molecules may represent an alternative mechanism by which galectins promote angiogenic responses and its selective blockade may lead to the development of therapeutic strategies for angiogenesis-related diseases. - Artículo
Acceso Abierto Response to long-term NaHCO3-derived alkalinity in model Lotus japonicus ecotypes Gifu B-129 and Miyakojima MG-20: transcriptomic profiling and physiological characterization(2014) Campestre, María Paula; Babuin, Maria Florencia; Rocco, Rubén; Bordenave, Cesar Daniel; Escaray, Francisco José; Antonelli, Cristian Javier; Calzadilla, Pablo; Gárriz, Andrés; Serna, Eva; Carrasco, Pedro; Ruiz, Oscar Adolfo; Menéndez, Ana B.The current knowledge regarding transcriptomic changes induced by alkalinity on plants is scarce and limited to studies where plants were subjected to the alkaline salt for periods not longer than 48 h, so there is no information available regarding the regulation of genes involved in the generation of a new homeostatic cellular condition after long-term alkaline stress. Lotus japonicus is a model legume broadly used to study many important physiological processes including biotic interactions and biotic and abiotic stresses. In the present study, we characterized phenotipically the response to alkaline stress of the most widely used L. japonicus ecotypes, Gifu B-129 and MG-20, and analyzed global transcriptome of plants subjected to 10 mM NaHCO3 during 21 days, by using the Affymetrix Lotus japonicus GeneChipH. Plant growth assessment, gas exchange parameters, chlorophyll a fluorescence transient (OJIP) analysis and metal accumulation supported the notion that MG-20 plants displayed a higher tolerance level to alkaline stress than Gifu B-129. Overall, 407 and 459 probe sets were regulated in MG-20 and Gifu B-129, respectively. The number of probe sets differentially expressed in roots was higher than that of shoots, regardless the ecotype. Gifu B-129 and MG-20 also differed in their regulation of genes that could play important roles in the generation of a new Fe/Zn homeostatic cellular condition, synthesis of plant compounds involved in stress response, protein-degradation, damage repair and root senescence, as well as in glycolysis, gluconeogenesis and TCA. In addition, there were differences between both ecotypes in the expression patterns of putative transcription factors that could determine distinct arrangements of flavonoid and isoflavonoid compounds. Our results provided a set of selected, differentially expressed genes deserving further investigation and suggested that the L. japonicus ecotypes could constitute a useful model to search for common and distinct tolerance mechanisms to long-term alkaline stress response in plants. - Artículo
Acceso Abierto Biosynthesis of SUMOylated proteins in bacteria using the Trypanosoma brucei enzymatic system(2015) Iribarren, Paula Ana; Berazategui, María Agustina; Cazzulo, Juan José; Álvarez, Vanina EderPost-translational modification with the Small Ubiquitin-like Modifier (SUMO) is conserved in eukaryotic organisms and plays important regulatory roles in proteins affecting diverse cellular processes. In Trypanosoma brucei, member of one of the earliest branches in eukaryotic evolution, SUMO is essential for normal cell cycle progression and is likely to be involved in the epigenetic control of genes crucial for parasite survival, such as those encoding the variant surface glycoproteins. Molecular pathways modulated by SUMO have started to be discovered by proteomic studies; however, characterization of functional consequences is limited to a reduced number of targets. Here we present a bacterial strain engineered to produce SUMOylated proteins, by transferring SUMO from T. brucei together with the enzymes essential for its activation and conjugation. Due to the lack of background in E. coli, this system is useful to express and identify SUMOylated proteins directly in cell lysates by immunoblotting, and SUMOylated targets can be eventually purified for biochemical or structural studies. We applied this strategy to describe the ability of TbSUMO to form chains in vitro and to detect SUMOylation of a model substrate, PCNA both from Saccharomyces cerevisiae and from T. brucei. To further validate targets, we applied an in vitro deconjugation assay using the T. brucei SUMO-specific protease capable to revert the pattern of modification. This system represents a valuable tool for target validation, mutant generation and functional studies of SUMOylated proteins in trypanosomatids. - Artículo
Acceso Abierto Lotus spp: Biotechnological strategies to improve the bioeconomy of lowlands in te Salado River Basin (Argentina)(2016) Antonelli, Cristian Javier; Calzadilla, Pablo I.; Escaray, Francisco José; Babuin,Maria F.; Campestre, María Paula; Rocco, Rubén; Bordenave, César D.; Perea García, Ana; Nieva, Amira S.; Llames, Maria E.; Maguire, Vanina; Melani, Gustavo; Serena, Daniel; Bailleres, Matías; Carrasco, Pedro; Paolocci, Francesco; Garriz, Andrés; Menéndez, Ana; Ruiz, Oscar AdolfoThe Salado River Basin region is the most important livestock breeding area in Argentina, wherethe Lotus species has been traditionally cultivated as forages. Nearly 60% of their land surface is dominated by salt-affected soils with severe constraints for crop cultivation. In order to cope with that limitation, farmers have utilized species such as non-native L. tenuis (ex- Lotus glaber), which shows a very good adaptation. As a result, inter-seeding of L. tenuis has been proposed as a strategy of choice for improving forage production in marginal areas. The increase in soil quality by these means is achieved by an increment of the organic matter content, improvement of soil fertility as well as microbial biodiversity. Thus, the introduction of L. tenuis and/or other Lotus genotypes could have enormous benefits for similar constrained lands around the world. We are developing an integrated analysis of the changes that occur in soils under legume production. We will not only analyze the microbial diversity associated, but also soil physical and chemical characteristics and the impact of different legume-microbes association on mitigation of GHG emissions. In addition, we are identifying the main genetic determinants associated with interesting agronomic traits such as plant tolerance against biotic and abiotic stresses and the content of condensed tannins. Our future and present research will build a solid base for the improvement of agronomicallyimportant species and the development of better strategies for the management of constrained lands such as the lowlands in the Argentinean Pampas. - Artículo
Acceso Abierto Guapa bajo el agua: Lotus tenuis(2017) Bailleres, Matias; Campestre, María Paula; Antonelli, Cristian JavierEsta forrajera no sólo resiste condiciones de encharcamiento, sino que con técnicas de manejo, se potencia - Artículo
Acceso Abierto SUMO polymeric chains are involved in nuclear foci formation and chromatin organization in Trypanosoma brucei procyclic forms(2018) Di Marzio, Lucia Ayelén; Berazategui, María Agustina; De Gaudenzi, Javier Gerado; Álvarez, Vanina Eder; Iribarren, Paula AnaSUMOylation is a post-translational modification conserved in eukaryotic organisms that involves the covalent attachment of the small ubiquitin-like protein SUMO to internal lysine residues in target proteins. This tag usually alters the interaction surface of the modified protein and can be translated into changes in its biological activity, stability or subcellular localization, among other possible outputs. SUMO can be attached as a single moiety or as SUMO polymers in case there are internal acceptor sites in SUMO itself. These chains have been shown to be important for proteasomal degradation as well as for the formation of subnuclear structures such as the synaptonemal complex in Saccharomyces cerevisiae or promyelocytic leukemia nuclear bodies in mammals. In this work, we have examined SUMO chain formation in the protozoan parasite Trypanosoma brucei. Using a recently developed bacterial strain engineered to produce SUMOylated proteins we confirmed the ability of TbSUMO to form polymers and determined the type of linkage using site-directed mutational analysis. By generating transgenic procyclic parasites unable to form chains we demonstrated that although not essential for normal growth, SUMO polymerization determines the localization of the modified proteins in the nucleus. In addition, FISH analysis of telomeres showed a differential positioning depending on the polySUMOylation abilities of the cells. Thus, our observations suggest that TbSUMO chains might play a role in establishing interaction platforms contributing to chromatin organization. - Artículo
Embargado Different proteomic strategies to identify genuine SUMO targets and their modification sites in Trypanosoma brucei procyclic forms(2015) Iribarren, Paula Ana; Berazategui, María Agustina; Bayona, Julio Cesar; Almeida, Igor; Cazzulo, Juan José; Álvarez, Vanina EderSUMOylation is an important post-translational modification conserved in eukaryotic organisms. In Trypanosoma brucei, SUMO (Small Ubiquitinlike MOdifier) is essential in procyclic and bloodstream forms. Furthermore, SUMO has been linked to the antigenic variation process, as a highly SUMOylated focus was recently identified within chromatin-associated proteins of the active variant surface glycoprotein expression site. We aimed to establish a reliable strategy to identify SUMO conjugates in T. brucei. We expressed various tagged variants of SUMO from the endogenous locus. HisHA-TbSUMO was useful to validate the tag functionality but SUMO conjugates were not enriched enough over contaminants after affinity purification. A Lys-deficient SUMO version, created to reduce contaminants by Lys-C digestion, was able to overcome this issue but did not allow mapping many SUMOylation sites. This cell line was in turn useful to demonstrate that polySUMO chains are not essential for parasite viability. Finally, a HisHA-TbSUMOT106K version allowed the purification of SUMO conjugates and, after digestion with Lys-C, the enrichment for diGly-Lys peptides using specific antibodies. This site-specific proteomic strategy led us to identify 45 SUMOylated proteins and 53 acceptor sites unambiguously. SUMOylated proteins belong mainly to nuclear processes, such as DNA replication and repair, transcription, rRNA biogenesis and chromatin remodelling, among others. - Artículo
Embargado High-level expression of Falcipain-2 in Escherichia coli by codon optimization and auto-induction(Elsevier, 2012) Salas Sarduy, Emir; Cabrera Muñoz, Aymara; Trejo, Sebastián Alejandro; Chavéz Planes, María de los A.Falcipain-2, the major cysteine hemoglobinase from the human malaria parasite Plasmodium falciparum, is critical for parasite development and is considered a promising chemotherapeutic target. In order to facilitate the high-throughput screening of Falcipain-2 inhibitors from natural sources, we developed an economic and highly-productive overexpression system in Escherichia coli using a codon-optimized proFalcipain-2 construct. Very high expression levels (35–55% of total host proteins) were observed when proFalcaipain-2 expression was induced with 1 mM isopropyl-1-thio-b-D-galactopyranoside (IPTG) in several E. coli strains, with the highest level observed for BL21(DE3). A lower expression ( 40% of total host proteins) was observed when BL21(DE3) was grown in ZYM-5052 auto-induction medium, containing 0.2% lactose as inducer. However, the culture grew to notably higher cellular density, increasing 1.5 times the overall yield of the system when compared with conventional IPTG-induction. Although several conditions were modified to achieve the expression of soluble and active Falcipain-2, the enzyme was mainly obtained in the form of insoluble aggregates. After purification and refolding, 50 mg of active enzyme were obtained per liter of culture at low cost using a regular incubator shaker, and recombinant Falcipain-2 exhibited structural and functional characteristics very similar to the natural counterpart. Due to its versatility and simplicity, this strategy can be straightforwardly adapted to other proteins from Plasmodium species or any other organism with an AT-rich genome. - Documento de conferencia
Acceso Abierto Proyecto para evaluar la generación de biogás a partir de los desechos de biomasa (sustrato gastado) de la producción de hongos comestibles(2017) Perez Chávez, Ana Marión; Mayer, Leopoldo; Albertó, EdgardoEn el último tiempo, la Argentina ha impulsado el uso de fuentes de energía renovables, lo que incluye la utilización de residuos agrícolas para generar bioenergía. El biogás es un combustible producido por digestión anaeróbica que ha sido considerado una de las tecnologías más sustentables y de bajo costo. En la producción de hongos se descartan miles de toneladas de sustrato lignocelulósico que podría emplearse para la generación de biogás, por haber sido sometido a un pretratamiento enzimático que hace más adecuados los materiales para la digestión bacteriana. Recientemente, hemos empleado el sustrato agotado de dos hongos comestibles para la producción de biogás: Pleurotus ostreatus con paja de trigo en codigestión con estiércol ovino, y aserrín proveniente de Gymnopilus pampeanus. Hemos probado que la acción del hongo en el sustrato favorece la generación de biogás. Para llevar a escala este proyecto, se instalará un laboratorio de análisis bioquímico que contará con tres biodigestores automatizados (15 L) en los cuales se evaluará la cantidad de biogás producido con varios sustratos agotados. Asimismo, se analizarán los lodos resultantes y se evaluará su uso como fertilizantes de campo. Adicionalmente, se montará un biodigestor de 50 m3 para determinar la producción de biogás a escala piloto. - Artículo
Acceso Abierto In vitro evaluation of β-carboline alkaloids as potential anti-Toxoplasma agents(BioMed Central, 2013) Alomar, María L.; Rasse-Suriani, Federico; Ganuza, Agustina; Cóceres, Verónica; Cabrerizo, Franco M.; Angel, Sergio OscarBackground: Toxoplasmosis is a worldwide infection caused by the protozoan parasite Toxoplasma gondii, which causes chorioretinitis and neurological defects in congenitally infected newborns or immunodeficient patients. The efficacy of the current treatment is limited, primarily by serious host toxicity. In recent years, research has focused on the development of new drugs against T. gondii. β-Carbolines (βCs), such as harmane, norharmane and harmine, are a group of naturally occurring alkaloids that show microbicidal activity. In this work, harmane, norharmane and harmine were tested against T. gondii. Findings: The treatment of extracellular tachyzoites with harmane, norharmane and harmine showed a 2.5 to 3.5- fold decrease in the invasion rates at doses of 40 μM (harmane and harmine) and 2.5 μM (norharmane) compared with the untreated parasites. Furthermore, an effect on the replication rate could also be observed with a decrease of 1 (harmane) and 2 (norharmane and harmine) division rounds at doses of 5 to 12.5 μM. In addition, the treated parasites presented either delayed or no monolayer lysis compared with the untreated parasites. Conclusions: The three βC alkaloids studied (norharmane, harmane and harmine) exhibit anti-T. gondii effects as evidenced by the partial inhibition of parasite invasion and replication. A dose–response effect was observed at a relatively low drug concentration (< 40 μM), at which no cytotoxic effect was observed on the host cell line (Vero). - Documento de conferencia
Acceso Abierto Instituto de Investigaciones Biotecnológicas -Instituto Biotecnológico de Chascomús (II-INTECH)(Comisión de Investigaciones Científicas de la Provincia de Buenos Aires (CICBA), 2016) Frasch, Alberto Carlos C.Exposición realizada en el marco del Encuentro del Ministerio de la Producción, Ciencia y Tecnología de la Provincia de Buenos Aires con autoridades y centros de la Comisión de Investigaciones Científicas de la Provincia de Buenos Aires. Exposiciones de los directores de los Centros de Investigación propios, asociados y vinculados.