María Julieta Binaghi

Effects of roasting and boiling of quinoa, kiwicha and kañiwa on composition and availability of minerals in vitro.

BACKGROUND Andean indigenous crops such as quinoa (Chenopodium quinoa), kiwicha (Amaranthus caudatus) and kañiwa (Chenopodium pallidicaule) seeds are good sources of minerals (calcium and iron). Little is known, however, about mineral bioavailability in these grains. Thus the aim of the present study was to determine the iron, calcium and zinc potential availability in raw, roasted and boiled quinoa, kañiwa and kiwicha seeds. Potential availability was estimated by dialyzability. RESULTS These seeds are good sources of phenolic compounds and kañiwa of dietary fiber. Their calcium, zinc and iron content is higher than in common cereals. In general, roasting did not significantly affect mineral dialyzability. Conversely, in boiled grains there was an increase in dialyzability of zinc and, in the case of kañiwa, also in iron and calcium dialyzability. CONCLUSION Taking into account the high content of minerals in Andean grains, the potential contribution of these minerals would not differ considerably from that of wheat flour. Further studies are required to research the effect of extrusion on mineral availability in Andean grains.

Progression of pregnancy-dependent mouse mammary tumors after long dormancy periods. Involvement of Wnt pathway activation

Mouse mammary tumor virus (LA) induces pregnancy-dependent mammary tumors that progress toward autonomy. Here we show that in virgin females, pregnancy-dependent tumor transplants are able to remain dormant for up to 300 days. During that period, these tumors synthesize DNA, express high levels of estrogen and progesterone receptors (ER+PR+) and are able to resume growth after hormone stimulation. Surprisingly, in a subsequent transplant generation, all these tumors are fully able to grow in virgin females, they express low levels of ER and PR (ER−PR−) and have a monoclonal origin; i.e., show all of the features we have described previously in pregnancy-independent tumors. Histologically, mouse mammary tumor virus (LA)-induced tumors are morphologically similar to genetically engineered mouse (GEM) mammary tumors that overexpress genes belonging to the Wnt pathway. Interestingly, in the virus-induced neoplasias, pregnancy-independent passages arising after a dormant phase usually display a lower level of glandular differentiation together with epithelial cell trans-differentiation, a specific feature associated to Wnt pathway activation. In addition, dormancy can lead to the specific selection of Int2/Fgf3 mutated and overexpressing cells. Therefore, our results indicate that during hormone-dependent tumor dormancy, relevant changes in cell population occur, allowing rapid progression after changes in the animal internal milieu.

DIALIZABILIDAD DE HIERRO Y ZINC EN CEREALES PARA DESAYUNOS COMERCIALES FORTIFICADOS CON HIERRO ELEMENTAL, SULFATO FERROSO O EDTA FERRICO SODICO

Se comparo la dializabilidad de Fe y Zn en 7 cereales para desayuno comercialmente fortificados o no, con Fe elemental y ZnO y se comparo la dializabilidad de Fe y Zn en tres tipos diferentes de cereales experimentalmente fortificados con ZnO y FeNa2EDTA o FeSO4 en el laboratorio. Se utilizo una metodologia in vitro que mide el porcentaje de dializabilidad (D%) del mineral en condiciones controladas de pH. Los cereales comercialmente fortificados presentaron valores de DFe% entre 0,4 y 15,0 y entre 1,0 y 5,6; sin y con leche. Para DZn% los valores fueron entre 3,3 y 16,1 y entre 3,3 y 30,8, sin y con leche. Casi todos los cereales fortificados en el laboratorio presentaron mayor DFe% (entre 19,5 y 28,6) y DZn% (entre 12,4 y 29,2) cuando fueron fortificados con FeNa2EDTA (con y sin leche). Los resultados obtenidos muestran al FeNa2EDTA como una alternativa viable para la fortificacion de cereales para desayuno.

Comparación de SDS-PAGE y métodos inmunoquímicos para la detección de proteínas de soja en productos cárnicos crudos y cocidos

The aim of this study was to evaluate the detection of soy proteins in raw and cooked meat products using SDS-PAGE and immunochemical methods. Ten raw model systems of bovine meat added with soy protein isolates, eight cooked model systems of boneless ham added with soy protein isolates and eight commercial meat products were analized. Model systems and commercial samples were analyzed by SDS-PAGE, Dot Blot, Immunoblotting and ELISA (Soy allergen kit from Neogen). Dot blot and Immunoblotting resulted to be the most sensitive analytical methods for the detection of soy proteins. The concentrations of the soy protein isolate obtained with the ELISA kit were much lower than real values. Soy proteins that were not declared in the label of several samples were detected using different methods. The heat treatment applied to the cooked meat products would affect the solubility of soy proteins and their ability to react with the antibodies of the ELISA kit used.

Diseño de panes funcionales a base de harinas no tradicionales

Functional breads constitute an interesting alternative as a vehicle of new dietary fiber sources. Two ingredients which are obtained and used at regional levels were studied: green banana flour (GBF) (Musa acuminata var nanica) and American carob flour (CF) (Prosopis alba). Breads were made mixing these flours with wheat flour (WF): GBF/WF 50:50 and CF/WF 25:75. Proximal composition of all samples was assessed according to AOAC methods. Iron, zinc and calcium contents were determined by AAS and mineral dialyzability using an in vitro method. The studied flours as well as the breads were characterized by high dietary fiber contents (12.4 and 31.0 in GBF and CF; and 6.9 and 10.2 in the green banana and carob breads, respectively). Breads had about 22% less available carbohydrates than white bread. Mineral dialyzability increased in breads about 30 to 50%, since fermentation promotes phytates degradation. The greatest effect was observed on iron dialyzability. These results indicate that these flours might be promising ingredients for use in the design of functional breads, with important levels of dietary fiber. These breads may be labeled as high fiber products according to current national regulations (minimum 6%). The inclusion of CF contributed to higher iron and calcium levels while the use of GBF, due to its functional properties, allowed for a greater replacement of wheat flour.

Abstract LB-43: Unveiling the molecular significance of HO-1 and muskelin interaction: two masterminds behind the morphology and the adhesive behavior of prostate cancer cells

Proceedings: AACR Annual Meeting 2014; April 5-9, 2014; San Diego, CA Prostate Cancer (PCa) is the second leading cause of cancer death in American men. The inflammatory tumor microenvironment is a fertile niche that releases reactive oxygen species, which accelerates the malignant transformation and appears as a fine tuner of the adhesive behavior of cells. Heme oxygenase 1 (HO-1), the rate-limiting enzyme in heme degradation, represents an essential event in cellular responses to pro-oxidative and pro-inflammatory insults. As we previously reported that HO-1 over-expression impaired tumor growth and angiogenesis in vivo we sought to assess whether HO-1 could regulate the adhesive properties and the morphology of PCa cells. A bioinformatics enrichment analysis using Metacore, GeneMANIA and DAVID was performed; rendering a significant association of the HO-1 regulated genes with several proteins located in the extracellular space and cell membrane; compartments highly correlated with the adhesive behavior of cells. In an effort to understand the molecular mechanisms underlying HO-1s role in cell morphology regulation we used a proteomics approach to identify HO-1 partners. We performed GST-pull-down assays using lysates from PC3 cells transfected with either GST-tagged HO-1 or the empty vector, and the isolated proteins were subjected to MALDI-TOF/TOF analyses. Our results showed that HO-1 interacts with Muskelin, a nucleocytoplasmic mediator of cellular morphology and adhesiveness. Up-regulation of Muskelin under HO-1 induction in PCa cells was confirmed by confocal microscopy. A high degree of nuclear overlay between HO-1 and Muskelin signals was observed when cells were exposed to hemin, a potent specific inducer of HO-1 or genetically manipulated to over-express HO-1, compared to controls. Interestingly after HO-1 induction, both protein exhibit similar sub-cellular dynamics, relocating from the cell membrane, towards the cell nuclei. Altogether, we have shown for the first time that HO-1 binds and up-regulates Muskelin, a specific factor involved in shaping cellular morphology and adhesive properties, favoring a less aggressive phenotype and further supporting the anti-tumoral function of HO-1in PCa. Citation Format: Geraldine Gueron, Jimena Giudice, Alejandra Paez, Pia Valacco, Noelia Carabelos, Federico Schuster, Javier Cotignola, Felipe Jaworski, Daiana Leonardi, Maria Binaghi, Marcelo Marti, Nora Navone, Elba Vazquez. Unveiling the molecular significance of HO-1 and muskelin interaction: two masterminds behind the morphology and the adhesive behavior of prostate cancer cells. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr LB-43. doi:10.1158/1538-7445.AM2014-LB-43

Biodisponibilidad de hierro en la dieta infantil

La alimentacion del nino en el primer ano de vida reviste gran importancia por las consecuencias negativas que las deficiencias nutricionales pueden tener sobre el crecimiento y desarrollo infantil, a corto y a largo plazo. Por ello es fundamental promover la lactancia exclusiva en los primeros 6 meses de vida, asi como incorporar oportunamente alimentos complementarios de calidad adecuada.1 En este contexto, se debe recordar que la deficiencia de hierro constituye la carencia nutricional mas comun en America latina y tambien en nuestro pais.2,3 Mantener el balance de minerales de acuerdo a los requerimientos fisiologicos requiere considerar, no solo la ingesta total de estos nutrientes, sino tambien su biodisponibilidad. Esta ultima supone la presencia en el alimento/dieta de compuestos que la favorezcan y la ausencia de otros que la inhiban. La forma quimica del mineral y su interaccion con componentes del alimento/dieta determinara variaciones en la biodisponibilidad que es preciso evaluar para conocer, no solo la cantidad aportada por el alimento, sino tambien la cantidad disponible para su bioutilizacion. Los metodos para evaluar la biodisponibilidad incluyen ensayos in vivo e in vitro. En algunos casos se utilizan ensayos en ratas. Sin embargo, el uso de modelos animales para evaluar la biodisponibilidad en seres humanos esta limitado por las diferencias entre especies, tanto en la velocidad de crecimiento como en la