Browsing by Subject "Proteins"

Now showing 1 - 11 of 11
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    AB deposition and related pathology in an APP x PS1 transgenic mouse model of Alzheimer s disease
    (Murcia : F. Hernández, 2008) Howlett, D.R.; Bowler, K.; Soden, P.E.; Riddell, D.; Davis, J.B.; Richardson, J.C.; Burbidge, S.A.; Gonzalez, M.I.; Irving, E.A.; Lawman, A.; Miglio, G.; Dawson, E.L.; Howlett, E.R.; Hussain, I.
    Summary. A transgenic mouse bearing mutant transgenes linked to familial forms of Alzheimer’s disease (AD) for the amyloid precursor protein and presenilin-1 (TASTPM) showed Aß plaque deposition and age-related histological changes in associated brain pathology. The Aß present was of multiple forms, including species with a C-terminus at position 40 or 42, as well as an N-terminus at position 1 or truncated in a pyro-3-glutamate form. Endogenous rodent Aß was also present in the deposits. Laser capture microdissection extracts showed that multimeric forms of Aß were present in both plaque and tissue surrounding plaques. Associated with the Aß deposits was evidence of an inflammatory response characterised by the presence of astrocytes. Also present in close association with the deposits was phosphorylated tau and cathepsin D immunolabelling. The incidence of astrocytes and of phosphorylated tau and cathepsin D load showed that both of these potential disease markers increased in parallel to the age of the mice and with Aß deposition. Immunohistochemical labelling of neurons in the cortex and hippocampus of TASTPM mice suggested that the areas of Aß deposition were associated with the loss of neurons. TASTPM mice, therefore, exhibit a number of the pathological characteristics of disease progression in AD and may provide a means for assessment of novel therapeutic agents directed towards modifying or halting disease progression.
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    Adecuación de las declaraciones de propiedades saludables en suplementos alimenticios deportivos a la legislación europea y evidencia científica
    (Universidad de Murcia, 2025-01-08) Rodríguez Hernández, María Dolores; Gil Izquierdo, Ángel; Escuela Internacional de Doctorado
    La utilización de productos ergogénicos que promueven un rendimiento físico mejor se ha convertido en un negocio lucrativo, son utilizados por los atletas en sus programas de entrenamiento y a veces, como alternativas para contrarrestar la falta de entrenamiento y compromiso. Los beneficios que ofrecen los suplementos no siempre se consiguen, sobre todo por la confusión existente en la publicidad que apoya y convence de los beneficios ergogénicos de varias sustancias. En Europa, los suplementos alimenticios deportivos (SAD) están condicionados por leyes y reglamentos específicos. Hasta el 70% de los deportistas son altamente influenciados por la información presente en la etiqueta o publicidad del SAD, que en muchas ocasiones la información, como las declaraciones de propiedades saludables, no se corresponde con la evidencia científica. En el estudio 1 se ha analizado las declaraciones de las bebidas de reposición (BR) presentes en los mensajes comerciales, realizando un estudio observacional y transversal basado en el análisis de contenido y grado de adecuación de las declaraciones de propiedades saludables indicadas en el etiquetado o ficha técnica de las BR con las establecidas por la legislación europea vigente según los dictámenes de la EFSA. La búsqueda fue a través de Amazon y Google Shopping. Se evaluaron 114 declaraciones de propiedades saludables, entre los resultados se obtuvo que ninguna declaración se adecuaba de manera total a las recomendaciones. 14 declaraciones (n= 13 productos) se adecuaban casi a las recomendaciones, siendo las de “mantener el nivel de resistencia en ejercicios que requieren una resistencia prolongada”, “mejoran la absorción de agua durante el ejercicio físico” y “mejora del rendimiento físico durante un ejercicio físico de alta intensidad y duración en adultos entrenados”, representando el 12.3% del total (n=114). La gran mayoría de las declaraciones identificadas indican una causa-efecto no demostrada debiendo ser modificadas o eliminadas. En el estudio 2 se ha analizado las declaraciones de propiedades saludables de los suplementos alimenticios deportivos a base de proteínas, realizando un estudio observacional y transversal basado en el análisis de contenido y grado de adecuación de las declaraciones de propiedades saludables indicadas en el etiquetado o ficha técnica de los suplementos alimenticios deportivos a base de proteínas con las establecidas por la legislación europea vigente y la evidencia descrita hasta la fecha actual. Además, el diseño del estudio como el desarrollo del manuscrito, siguió la declaración STROBE. La búsqueda de los productos de la muestra se realizó en octubre 2023 a través de las plataformas de compras web Amazon y Google Shopping. Estos sitios web fueron seleccionados porque son los principales sitios web de compras online. De las 209 declaraciones de propiedades saludables evaluadas, 60 declaraciones se adecuan de manera total a las recomendaciones, siendo “Las proteínas contribuyen a que aumente la masa muscular” “Las proteínas contribuyen a conservar la masa muscular” “Las proteínas contribuyen al mantenimiento de los huesos en condiciones normales”, representando el 28.7% del total (n=209). Frente a 12 declaraciones donde el texto de la declaración indicada no se ajusta a las declaraciones de propiedades saludables establecidas por la EFSA, representando el 5.7% del total (n=209). Las declaraciones de salud no autorizadas más usadas en el mercado son referente a “Recuperación post-entrenamiento” encontrándose en un 11.1%. Seguido de “Favorece la recuperación muscular (caseína)”, encontrándose cada una en el 9.5%. Referidas a la proteína de suero, y a la caseína, respectivamente. De todos los productos analizados en el estudio, el 43.8% (n=46) de los productos nombran declaraciones de salud no autorizadas por la EFSA. Teniendo en cuenta todos los resultados, podríamos decir que las declaraciones de propiedades saludables presentes en los suplementos alimenticios deportivos analizados, bebidas de reposición y suplementos con proteínas, deben adecuarse firmemente a los criterios establecidos por la legislación europea, los documentos de consenso y la evidencia científica. El fraude alimentario se encuentra en diversas formas dentro de la publicidad, el marketing y la comercialización de los alimentos, afectando fuertemente a los consumidores.
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    Alterations of the cerebrospinal fluid proteins and subcommissural organ secretion in the arterial hypertension and ventricular dilatation. A study in SHR rats
    (Murcia : F. Hernández, 2006) Martínez de la Peña y Valenzuela, Isabel; Carmona-Calero, E.; Pérez-González, H.; Ormazabal-Ramos, C.; Fernández-Rodríguez, P.; Gonzalez-Marrero, I.; Castañeyra Perdomo, A.; Ferres Torres, R.
    The aim of this work was to analyze the proteins in the cerebrospinal fluid (CSF) of spontaneously hypertensive rats, to study their possible role in the relationship between hydrocephalus, arterial hypertension and alterations in the subcommissural organ. Brains from control Wistar-Kyoto rats (WKY) and spontaneously hypertensive rats (SHR) sacrificed with chloral hydrate were used. Antiserums against some cerebrospinal fluid protein bands and Reissner’s fiber (RF) were used for immunohistochemical study of the SCO. Ventricular dilation was observed in the lateral and third ventricle of the SHR. Third ventricle ependyma showed immunoreactive material (IRM) for antibody against 141kDa protein band anti-B1 and 117 protein band anti-B2 and the SCO of the SHR showed a decrease of the IRM when compared with WKY rats. An alteration in the expression of anti-RF was found to compare the SCO of the WKY and SHR groups. Our results demonstrate that hydrocephalus and hypertension are interconnected in this kind of rat which produce alterations in SCO secretions and some proteins of the CSF.
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    Animales transgénicos para producción de proteínas humanas
    (Universidad de Murcia, 2014) Sánchez, Araceli; Gadea Mateos, Joaquín
    Con la aparición en los años ochenta de los animales transgénicos se abrió un amplio e importante campo de estudio, ya que estos animales pueden ser utilizados como modelos de investigación de enfermedades humanas, como donantes de órganos o para producir en ellos proteína de interés. La industria farmacéutica vio, en este último uso de los animales transgénicos, una gran oportunidad para la producción de proteínas humanas a bajo coste. Este método presentaba numerosas ventajas frente a los anteriores métodos de producción de proteínas. A diferencia de las proteínas producidas en hongos, bacterias y plantas, las proteínas producidas en animales transgénicos sufren modificaciones postraduccionales completas y son totalmente activas. Además la obtención de dichas proteínas conllevaría muy bajo coste una vez producido el animal transgénico, a diferencia del elevado coste de la producción en cultivos de celulares a gran escala. Pese a estas ventajas, problemas éticos del uso de animales, así como posibles consecuencias para la salud humana, han hecho que desde hace algunos años la investigación en estos animales para producir en ellos proteínas haya disminuido considerablemente. En este artículo se hace una revisión de los diferentes métodos de producción tanto de proteínas como de animales transgénicos. Nos centraremos finalmente en la producción de proteínas en la glándula mamaria, como principal tejido de producción, así como ejemplos de estas proteínas producidas.
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    Changes of the salivary and serum proteome in canine hypothyroidism
    (Elsevier, 2024-01) González Arostegui, L. G.; Muñoz Prieto, Alberto; Rubio, C. P.; Cerón, J. J.; Bernal, L.; Rubić, I.; Mrljak, V.; González Sánchez, J. C.; Tvarijonaviciute, Asta; Medicina y Cirugía Animal
    In this study, changes in salivary and serum proteome of dogs with hypothyroidism were studied using tandem mass tags (TMT) labelling and liquid chromatography-mass spectrometry (LC-MS/MS). Saliva and serum proteome from 10 dogs with hypothyroidism were compared with 10 healthy dogs. In saliva, a total of seven proteins showed significant changes between the two groups, being six downregulated and one upregulated, meanwhile, in serum, a total of six proteins showed significant changes, being five downregulated and one upregulated. The altered proteins reflected metabolic and immunologic changes, as well as, skin and coagulation alterations, and these proteins were not affected by gender. One of the proteins that were downregulated in saliva, lactate dehydrognease (LDH), was measured by a spectrophotometric assay in saliva samples from 42 dogs with hypothyroidism, 42 dogs with non-thyroid diseases and 46 healthy dogs. The activity of LDH was lower in the saliva of hypothyroid dogs when compared to non-thyroid diseased dogs and healthy controls. This study indicates that canine hypothyroidism can produce changes in the proteome of saliva and serum. These two sample types showed different variations in their proteins reflecting physiopathological changes that occur in this disease, mainly related to the immune system, metabolism, skin and coagulation. In addition, some of the proteins identified in this study, specially LDH in saliva, should be further explored as potential biomarkers of canine hypothyroidism.
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    Direct Cryo-ET observation of platelet deformation induced by SARS-CoV-2 spike protein
    (Nature Research, 2023-02-04) Cyrus Kuhn, Christopher; Basnet, Nirakar; Bodakuntla, Satish; Alvarez-Brecht, Pelayo; Nichols, Scott; Martínez-Sánchez, Antonio; Agostini, Lorenzo; Soh, Young-Min; Takagi, Junichi; Biertümpfel, Christian; Mizuno, Naoko; Ingeniería de la Información y las Comunicaciones
    SARS-CoV-2 is a novel coronavirus responsible for the COVID-19 pandemic. Its high pathogenicity is due to SARS-CoV-2 spike protein (S protein) contacting host-cell receptors. A critical hallmark of COVID-19 is the occurrence of coagulopathies. Here, we report the direct observation of the interactions between S protein and platelets. Live imaging shows that the S protein triggers platelets to deform dynamically, in some cases, leading to their irreversible activation. Cellular cryo-electron tomography reveals dense decorations of S protein on the platelet surface, inducing filopodia formation. Hypothesizing that S protein binds to filopodia-inducing integrin receptors, we tested the binding to RGD motif-recognizing platelet integrins and find that S protein recognizes integrin αvβ3. Our results infer that the stochastic activation of platelets is due to weak interactions of S protein with integrin, which can attribute to the pathogenesis of COVID-19 and the occurrence of rare but severe coagulopathies.
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    Expression of certain proteins in the subfornical organ and cerebrospinal fluid of spontaneously hypertensive rats
    (Murcia: F. Hernández, 2007) Gonzalez-Marrero, I.; Carmona-Calero, E.; Fernández-Rodríguez, P.; Pérez-González, H.; Ormazabal-Ramos, C.; Castañeyra-Ruíz, L.; Perez-Garcia, C.G.; Martínez de la Peña y Valenzuela, Isabel; Castañeyra-Ruiz, A.; Castañeyra Perdomo, A.; Ferres Torres, R.
    The objective of this study was to analyze the proteins in the cerebrospinal fluid of spontaneously hypertensive rats and to study their possible role in the relationship between hydrocephalus, arterial hypertension and variations in the subfornical organ. Brains and cerebrospinal fluid from control Wistar- Kyoto rats and spontaneously hypertensive rats sacrificed with chloral hydrate were used. Cerebrospinal fluid and extract of subfornical organ were processed by protein electrophoresis. Antisera against protein bands of 141, 117 and 48 kDa and Concanavalin A were used for immunohistochemical and western blot study of the subfornical organ, adjacent circumventricular structures and cerebrospinal fluid. Ventricular dilation in the spontaneously hypertensive rats and the presence of quite a lot of protein bands in the cerebrospinal fluid of the hypertensive rats, which were either not observed or scarcely present in the cerebrospinal fluid of the Wistar- Kyoto rats, were confirmed. The subfornical organ, third ventricle ependyma and choroideus plexus showed immunoreactive material for antibodies against 141kDa, 117 and 48 kDa proteins band (anti-B1, anti-B2 and anti- B3). The larger amount of the immunoreactive material was found in the subfornical organ of the spontaneously hypertensive rat. Our results and the alterations observed by other authors in the subfornical organ in hydrocephalic and hypertensive rats support the possibility that this circumventricular organ, some proteins of the cerebrospinal fluid and ventricular dilation could be connected with the physiopathology of this type of hypertension.
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    Histochemical study of skin and gills of Senegal sole, Solea senegalensis larvae and adults
    (Murcia : F. Hernández, 1998) Sarasquete, C.; Gonzalez de Canales, M.L.; Arellano, J.M.; Muñoz Cueto, J.A.; Ribeiro, L.; Dinis, M.T.
    A battery of horseradish peroxidaseconjugated lectins (Con A, WGA and DBA), as well as conventional histochemical techniques (PAS, saponification, Alcian Blue pH 0.1, 1, 2.5, chlorhydric hydrolisis, neuraminidase, Bromophenol blue, Tioglycollate reduction and Ferric-ferricyanide-FeIII) were used to study the content and distribution of carbohydrates, proteins and glycoconjugate sugar residues on the skin and gills of Senegal sole, Solea senegalensis larvae and adults. During larval development of Solea senegalensis (from hatching until day 45 posthatching), epidermal sacciform, as well as branchial and epidermal chloride cells were unreactive with all cytochemical tests performed in this paper. Mucous or goblet cells of the corporal skin and gills containing strongly sulphated acid glycoproteins were evident on days 15-20 of larval development, as well as in epidermal and branchial mucous cells of adult specimens, which also contained GlcNAc andlor sialic acid. In adult specimen, the proteic content was higher in branchial mucous cells than in epidermal cells. In larvae, variable amounts of glycoproteins containing sialic acid, GlcNAc, GalNAc, Man andlor Glc residues were observed in epithelia1 cells and/or cuticle. GlcNAc andlor sialic acid sugar residues were only weakly detected in glycoproteins of some epidermal and branchial mucous cells of larvae by day 45, because from hatching until metamorphosis, lectin reactions (WGA, Con A and DBA) were negative in mucous cells.
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    Isolation of high quality protein samples from punches of formalin fixed and paraffin embedded tissue blocks
    (Murcia : F. Hernández, 2008) Kroll, J.; Becker, K.F.; Kuphal, S.; Hein, R.; Hofstädter, F.; Bosserhoff, A.K.
    In general, it is believed that the extraction of proteins from formalin-fixed paraffin embedded samples is not feasible. However, recently a new technique was developed, presenting the extraction of non-degraded, full length proteins from formalin fixed tissues, usable for western blotting and protein arrays. In the study presented here, we applied this technique to punch biopsies of formalin fixed tissues embedded in paraffin to reduce heterogeneity of the tissue represented in sections, and to ensure analysing mainly defined cellular material. Successful extraction was achieved even from very small samples (0.7 mm3). Additionally, we were able to detect highly glycosylated proteins and protein modification, such as phosphorylation. Interestingly, with this technique it is feasible to extract high quality proteins from 14 year old samples. In summary, the new technique makes a great pool of material now usable for molecular analysis with high throughput tools.
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    MALDI mass spectrometry imaging of formalin-fixed paraffin-embedded tissues in clinical research
    (F. Hernández y Juan F. Madrid. Universidad de Murcia: Departamento de Biología Celular e Histología, 2014) Gorzolka, Karin; Walch, Axel
    The molecular investigation of archived formalin-fixed, paraffin-embedded (FFPE) tissue samples provides the chance to obtain molecular patterns as indicatives for treatment and clinical end points. MALDI mass spectrometry imaging is capable of localizing molecules like proteins and peptides in tissue sections and became a favorite platform for the targeted and non-targeted approaches, especially in clinical investigations for biomarker research. In FFPE tissues the recovery of proteomic information is constrained by fixation-induced cross-links of proteins. The promising new insights obtained from FFPE in combination with the comprehensive patients’ data caused much progress in the optimization of MS imaging protocols to investigate FFPE samples. This review presents the past and current research in MALDI MS imaging of FFPE tissues, demonstrating the improvement of analyses, their actual limitations, but also the promising future perspectives for histopathological and tissue-based research.
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    Seminal extracellular vesicles and their involvement in male (In)fertility: a systematic review
    (MDPI, 2023-03-02) Parra, Ana; Padilla, Lorena; Lucas, Xiomara; Rodríguez Martínez, Heriberto; Barranco, Isabel; Roca, Jordi; Medicina y Cirugía Animal
    Seminal plasma contains numerous extracellular vesicles (sEVs). Since sEVs are apparently involved in male (in)fertility, this systematic review focused on studies specifically investigating such relationship. Embase, PubMed, and Scopus databases were searched up to 31 December 2022, primarily identifying a total of 1440 articles. After processing for screening and eligibility, 305 studies were selected as they focused on sEVs, and 42 of them were considered eligible because they included the word fertility or a related word such as infertility, subfertility, fertilization, and recurrent pregnancy loss in the title, objective(s), and/or keywords. Only nine of them met the inclusion criteria, namely (a) conducting experiments aimed at associating sEVs with fertility concerns and (b) isolating and adequately characterizing sEVs. Six studies were conducted on humans, two on laboratory animals, and one on livestock. The studies highlighted some sEV molecules, specifically proteins and small non-coding RNAs, that showed differences between fertile and subfertile or infertile males. The content of sEVs was also related to sperm fertilizing capacity, embryo development, and implantation. Bioinformatic analysis revealed that several of the highlighted sEV fertility-related proteins would be cross-linked to each other and involved in biological pathways related to (i) EV release and loading and (ii) plasma membrane organization.