Effect of temperature on whey protein isolated (WPI) films adsorbed at the water-oil interface.

En este trabajo se ha estudiado la agregación interfacial inducida por el calor en un aislado proteico del suero bovino (WPI), previamente adsorbido sobre la interfase aceite-agua. Se ha seguido la evolución, durante el tratamiento térmico, de las características dinámicas interfaciales (tensión interfacial y propiedades dilatacionales superficiales), determinadas en un tensiómetro dinámico de gota, en unión de la observación microscópica y posterior análisis de la imagen de una gota que tiene adsorbida a la proteína sobre su superficie. Las variables estudiadas fueron la temperatura (en el intervalo comprendido entre 20 y 80 o C) y la concentración de proteína en el seno de la fase acuosa (en el intervalo comprendido entre 1.10 -1 y 1.10 -5 % en peso). Durante el tratamiento térmico, (a) la película de WPI presenta un comportamiento viscoelástico, con un ángulo de fase distinto de cero, (b) se incrementa el carácter elástico de la interfase, (c) se produce un incremento del módulo dilatacional superficial (E) y (d) una disminución de la tensión interfacial. La variación de E con el tiempo puede cuantificarse mediante ecuaciones de primer orden que pueden relacionarse con dos mecanismos cinéticos, asociados con la gelificación de WPI sobre la interfase aceite-agua. El tratamiento térmico produce cambios irreversibles en la película de WPI adsorbida sobre la interfase. Se han observado cambios significativos en las características interfaciales y en la imagen de la gota a concentraciones de proteína tan bajas como 1.10 -5 % en peso.Heat-induced interfacial aggregation of a whey protein isolate (WPI) with a high content of β -lactoglobulin, previously adsorbed at the oil-water interface, was studied by interfacial dynamic characteristics (interfacial tension and surface dilational properties) performed in an automatic drop tensiometer coupled with microscopic observation and image analysis of the drop after heat-treatment. The temperature, ranging between 20 and 80 o C, and protein concentration in aqueous bulk phase, ranging between 1.10 -1 and 1.10 -5 % wt/wt, were studied as variables. The pH, and ionic strength were maintained constant at 5 and 0.05 M, respectively. During the heat-treatment, WPI films behave typically as viscoelastic with non-zero phase angle, but with increasing elastic characteristics as the heat-treatment progresses. During isothermal treatment the surface dilational modulus, E, increases and the interfacial tension, σ , and phase angle, φ , decrease with time to a plateau value. The time dependence of E can be quantified by a first-order equation according to two kinetic mechanisms. The rate of thermal changes in WPI adsorbed films increases with protein concentration in solution. Heat-treatment produces irreversible changes in WPI adsorbed films because the interfacial characteristics do not return to original values after cooling back to the initial temperature. Significant changes in interfacial characteristics and drop image associated with interfacial WPI gelation were observed at protein concentration as low as 1.10 -5 % wt/wt, even for heat-treatment at 40 o C

Monocapas de ácidos grasos. III. Ácidos paimítico, láurico y oleíco sobre disoluciones acuosas que contienen solutos con grupos funcionales alcohólicos.

Monocapas de ácidos grasos. III. Ácidos palmítico, láurico y oleico sobre disoluciones acuosas que contienen solutos con grupos funcionales alcohólicos. Se ha estudiado la influencia que ejercen la longitud y la insaturación de la cadena acílica sobre las características de las monocapas de ácidos grasos sparcidas sobre medios acuosos que contienen etanol, glicerina, glucosa o sacarosa, utilizando una balanza de superficie de tipo Langmuir. La estabilidad de la monocapa es función de la longitud de la cadena acílica y de la presencia de insaturación. En general, los mismos factores que disminuyen la estabilidad de la monocapa pueden favorecer las transiciones iiacia configuraciones con estructuras más expandidasMonolayers of fatty acids. III. Palmitic, Laurie and Oleic Acids on aqueous solutions containig solutes witli alcoholic functional groups. Tiie influence exerted by the length or the insaturation of acyl chain on characteristics of fatty acid monolayers spread on aqueous solutions containing ethanol, glycerol, glucose or sucrose, is studied using a Langmuir type surface balance. The monolayer stability is function of acyl chain length and presence of insaturarion. Generally, the factors decreasing monolayer stability can help transformations towards configurations with more expanded structures

Monocapas de ácidos grasos I. Ácido esteárico sobre disoluciones acuosas de etanol

Monocapas de ácidos grasos. I. Acido esteárico sobre disoluciones acuosas de etanol. Se ha estudiado la estructura y estabilidad de monocapas de ácido esteárico esparcidas sobre disoluciones acuosas que contienen etanol. Las experiencias se han realizado en una iaalanza de superficie comercial tipo Langmuir y se ha operado en condiciones isotérmicas. Las monocapas presentan estructuras de tipo sólida o de líquido condensado en función de la concentración de etanol en la subíase. La estructura que adopta la monocapa es prácticamente independiente de la temperatura. La pérdida de moléculas de ácido esteárico de la monocapa por disolución en la subíase se incrementa a los valores más elevados de temperatura y de concentración de etanol.Monolayers of fatty acids. I. Stearic acid on aqueous solutions of ethanol. The structure and stability of fatty acid monolayers spread on aqueous solutions with ethanol has been studied. The experiments were carried out isothermically using a commercial Langmuir balance (Lauda). Monolayers exhibit solid or condensed liquid structure depending of the ethanol concentration in the subphase. Temperature has not a significant influence on the monolayer. Structure there is a loss of stearic acid film through solution into the adjacent subphase. This loss is increased with the temperature and ethanol concentration in the subphase

Monolayers of fatty acids. II. Stearic acid on aqueous solutions containing solutes with alcoholic functional groups

Se ha estudiado la estructura y estabilidad de monocapas de ácido esteárico esparcidas sobre disoluciones acuosas que contienen glicerina, glucosa y sacarosa. Las experiencias se han realizado en una balanza de superficie connercial tipo Langmuir y se ha operado en condiciones isotérmicas. Las monocapas presentan un polimorfismo estructural que depende de la composición del medio acuoso y de la temperatura. La estabilidad de la monocapa está muy relacionada con la estructura que adopta sus moléculas. Las monocapas con estructuras más expandidas suelen poseer mayor estabilidad.The structure and the stability of stearic acid monolayers spread on aqueous solutions with glycerol, glucose or sucrose are studied using a commercial film balance (Lauda). The experiments were carried out isothermically. Monolayers exhibit structural polymorphism depending on temperature and subphase composition. The stability of the molecules on the subphase is a function of their structure. Generally, the most stable monolaye|rs are those with more expanded structure

Incorporación de nuevos ingredientes funcionales a alimentos como contribución a la promoción de la salud y/o a la prevención de enfermedades de la población iberoamericana

Coordinador: Javier Fontecha.-- et al.El desarrollo de nuevos alimentos que incorporen ingredientes funcionales requiere un enfoque multidisciplinar, por lo que se considera esencial la participación conjunta de grupos de investigación internacionalmente reconocidos, entre los que surjan sinergias, colaboraciones e intercambios, que permitan la obtención de resultados de investigación difícilmente alcanzables por un solo grupo. En la presente propuesta, se promueve la interacción, la cooperación y la transferencia de conocimientos y tecnologías relacionadas con compuestos bioactivos, suficientemente caracterizados por los diferentes grupos que componen esta acción, que integren sus tareas mediante la interconexión con empresas especializadas en ingredientes funcionales, permitiendo una mejor transferencia al sector productivo y por tanto, un aumento de su competitividad.PROYECTO CYTED. IBEROFUN. REF: 110AC0386.Peer reviewe

Intermediate Molecular Phenotypes to Identify Genetic Markers of Anthracycline-Induced Cardiotoxicity Risk.

Cardiotoxicity due to anthracyclines (CDA) affects cancer patients, but we cannot predict who may suffer from this complication. CDA is a complex trait with a polygenic component that is mainly unidentified. We propose that levels of intermediate molecular phenotypes (IMPs) in the myocardium associated with histopathological damage could explain CDA susceptibility, so variants of genes encoding these IMPs could identify patients susceptible to this complication. Thus, a genetically heterogeneous cohort of mice (n = 165) generated by backcrossing were treated with doxorubicin and docetaxel. We quantified heart fibrosis using an Ariol slide scanner and intramyocardial levels of IMPs using multiplex bead arrays and QPCR. We identified quantitative trait loci linked to IMPs (ipQTLs) and cdaQTLs via linkage analysis. In three cancer patient cohorts, CDA was quantified using echocardiography or Cardiac Magnetic Resonance. CDA behaves as a complex trait in the mouse cohort. IMP levels in the myocardium were associated with CDA. ipQTLs integrated into genetic models with cdaQTLs account for more CDA phenotypic variation than that explained by cda-QTLs alone. Allelic forms of genes encoding IMPs associated with CDA in mice, including AKT1, MAPK14, MAPK8, STAT3, CAS3, and TP53, are genetic determinants of CDA in patients. Two genetic risk scores for pediatric patients (n = 71) and women with breast cancer (n = 420) were generated using machine-learning Least Absolute Shrinkage and Selection Operator (LASSO) regression. Thus, IMPs associated with heart damage identify genetic markers of CDA risk, thereby allowing more personalized patient management.J.P.L.’s lab is sponsored by Grant PID2020-118527RB-I00 funded by MCIN/AEI/10.13039/ 501100011039; Grant PDC2021-121735-I00 funded by MCIN/AEI/10.13039/501100011039 and by the “European Union Next Generation EU/PRTR”, the Regional Government of Castile and León (CSI144P20). J.P.L. and P.L.S. are supported by the Carlos III Health Institute (PIE14/00066). AGN laboratory and human patients’ studies are supported by an ISCIII project grant (PI18/01242). The Human Genotyping unit is a member of CeGen, PRB3, and is supported by grant PT17/0019 of the PE I + D + i 2013–2016, funded by ISCIII and ERDF. SCLl is supported by MINECO/FEDER research grants (RTI2018-094130-B-100). CH was supported by the Department of Defense (DoD) BCRP, No. BC190820; and the National Cancer Institute (NCI) at the National Institutes of Health (NIH), No. R01CA184476. Lawrence Berkeley National Laboratory (LBNL) is a multi-program national laboratory operated by the University of California for the DOE under contract DE AC02-05CH11231. The Proteomics Unit belongs to ProteoRed, PRB3-ISCIII, supported by grant PT17/0019/0023 of the PE I + D +i, 2017–2020, funded by ISCIII and FEDER. RCC is funded by fellowships from the Spanish Regional Government of Castile and León. NGS is a recipient of an FPU fellowship (MINECO/FEDER). hiPSC-CM studies were funded in part by the “la Caixa” Banking Foundation under the project code HR18-00304 and a Severo Ochoa CNIC Intramural Project (Exp. 12-2016 IGP) to J.J.S

Identification of genetic variants associated with Huntington's disease progression: a genome-wide association study

Background Huntington's disease is caused by a CAG repeat expansion in the huntingtin gene, HTT. Age at onset has been used as a quantitative phenotype in genetic analysis looking for Huntington's disease modifiers, but is hard to define and not always available. Therefore, we aimed to generate a novel measure of disease progression and to identify genetic markers associated with this progression measure. Methods We generated a progression score on the basis of principal component analysis of prospectively acquired longitudinal changes in motor, cognitive, and imaging measures in the 218 indivduals in the TRACK-HD cohort of Huntington's disease gene mutation carriers (data collected 2008–11). We generated a parallel progression score using data from 1773 previously genotyped participants from the European Huntington's Disease Network REGISTRY study of Huntington's disease mutation carriers (data collected 2003–13). We did a genome-wide association analyses in terms of progression for 216 TRACK-HD participants and 1773 REGISTRY participants, then a meta-analysis of these results was undertaken. Findings Longitudinal motor, cognitive, and imaging scores were correlated with each other in TRACK-HD participants, justifying use of a single, cross-domain measure of disease progression in both studies. The TRACK-HD and REGISTRY progression measures were correlated with each other (r=0·674), and with age at onset (TRACK-HD, r=0·315; REGISTRY, r=0·234). The meta-analysis of progression in TRACK-HD and REGISTRY gave a genome-wide significant signal (p=1·12 × 10−10) on chromosome 5 spanning three genes: MSH3, DHFR, and MTRNR2L2. The genes in this locus were associated with progression in TRACK-HD (MSH3 p=2·94 × 10−8 DHFR p=8·37 × 10−7 MTRNR2L2 p=2·15 × 10−9) and to a lesser extent in REGISTRY (MSH3 p=9·36 × 10−4 DHFR p=8·45 × 10−4 MTRNR2L2 p=1·20 × 10−3). The lead single nucleotide polymorphism (SNP) in TRACK-HD (rs557874766) was genome-wide significant in the meta-analysis (p=1·58 × 10−8), and encodes an aminoacid change (Pro67Ala) in MSH3. In TRACK-HD, each copy of the minor allele at this SNP was associated with a 0·4 units per year (95% CI 0·16–0·66) reduction in the rate of change of the Unified Huntington's Disease Rating Scale (UHDRS) Total Motor Score, and a reduction of 0·12 units per year (95% CI 0·06–0·18) in the rate of change of UHDRS Total Functional Capacity score. These associations remained significant after adjusting for age of onset. Interpretation The multidomain progression measure in TRACK-HD was associated with a functional variant that was genome-wide significant in our meta-analysis. The association in only 216 participants implies that the progression measure is a sensitive reflection of disease burden, that the effect size at this locus is large, or both. Knockout of Msh3 reduces somatic expansion in Huntington's disease mouse models, suggesting this mechanism as an area for future therapeutic investigation

Interfacial and foaming properties of bovine β-lactoglobulin: Galactose Maillard conjugates

In this paper, the effect of the initial and advanced steps of glycosylation by Maillard reaction (MR) (glycation) of β-lactoglobulin (β-Lg) with galactose on the interfacial and foaming (foamability and foam stability) properties of this protein has been studied at both pH7 and pH5. Hardly any effect of glycation was observed at pH7. However, a pH5, due to its increased solubility, β-Lg glycated at 50°C during 48h (advanced steps of MR) presented the best dynamic of adsorption which lead to an increase of the surface dilatational modulus of adsorbed film. This resulted in a better foaming capacity, as well as higher stability of foams of β-Lg glycoconjugates with respect to native and control heated protein. These results could extend the applicability of β-Lg as a foaming agent, particularly in acid foods. © 2011 Elsevier Ltd.This work has been funded by projects ALIBIRD S2009/AGR- 1469 (CAM), CICYT through Grant AGL2007-60045, and IBEROFUN 110AC0386 (CYTED)Peer Reviewe

Effect of glycation and limited hydrolysis on interfacial and foaming properties of bovine β-lactoglobulin

The effect of limited hydrolysis followed by glycation with galactose, and vice versa, on interfacial and foaming (foamability and foam stability) properties of β-lactoglobulin (β-Lg) at pH 7 and pH 5 has been studied. Hardly any effect of the two treatments, hydrolysis and glycation (HG) or glycation and hydrolysis (GH), on the β-Lg foaming capacity at both pH values was observed. Foam stability, however, was significantly enhanced after both HG and GH at pH 5. Particularly, the system obtained after glycation at 50 °C followed by limited hydrolysis showed an exceptional stability, which might be related to the increase in elastic character and cohesion of the interfacial film, indicated by the increase of the surface dilatational modulus (E) and the decrease of the phase angle (ϕ) over the time. These results indicated that glycation of β-Lg with galactose followed by limited hydrolysis might allow extending the use of this protein as foaming agent, although further research in complex food systems is needed to apply this method in the formulation of acidic foods and beverages.This work has been funded by projects AGL2011-27884.Peer Reviewe

Assessment of interfacial and foaming properties of bovine sodium caseinate glycated with galactose

The impact of the initial and advanced stages of glycation of sodium caseinate (SC) with galactose on the interfacial and foaming properties has been investigated at pH 7 and 5. At pH 7, the most remarkable result was the higher stabilizing foam capacity of glycoconjugates as compared to native and heat treated SC, as a result of the higher elastic character and cohesion of the interfacial film formed by glycated SC. At pH 5, native and control heated SC underwent a significant loss of solubility, resulting in a worse dynamic of adsorption at the interface of such systems and the formation of fluid and poorly resistant films. However, solubility of glycated SC remained relatively high, so that, at this pH, only SC glycoconjugates showed interfacial characteristics suitable to stabilize the foam during its formation as well as against mechanisms of foam destabilization at long term. This behavior was attributed to the higher adsorption efficiency and degree of interfacial interaction exhibited by the SC glycoconjugates. These findings highlight the beneficial effect of glycation on the foaming properties of SC which could contribute to broadening the applicability of SC as a foaming agent, mainly in acid foods. © 2012 Elsevier Ltd. All rights reserved.This work has been funded by Projects Consolider Ingenio 2010 FUN-c-FOOD CSD2007-00063 (MICINN), CICYT through Grant AGL2007-60045, and IBEROFUN 110AC0386 (CYTED). M. Corzo-Martínez thanks Danone Institute for a Grant.Peer Reviewe