Clinical and basic relevance of the phosphate overload on FGF23 renal receptors and chronic kidney disease progression

La enfermedad renal crónica (ERC) es una patología prevalente que se asocia a alteraciones en el metabolismo óseo mineral, alto riesgo cardiovascular y mortalidad. Por ello, es necesaria la realización de investigaciones dirigidas tanto a prevenir como a identificar los mecanismos de progresión de la ERC. El fósforo sérico incrementa con el deterioro de la función renal y a su vez es un factor de riesgo de progresión de ERC. Por otro lado, el factor de crecimiento fibroblástico 23 (FGF23) es una hormona fosfatúrica clave en este contexto ya que se encarga fundamentalmente de la excreción urinaria de fósforo. Por esta razón, el objetivo general de esta tesis es estudiar los mecanismos que subyacen a la resistencia a FGF23 e identificar un biomarcador capaz de predecir la progresión de la ERC. Inicialmente planteamos modelos experimentales animales e in vitro para determinar los mecanismos responsables de la resistencia de FGF23. Para ello, se evaluó el efecto de la administración de FGF23 recombinante en ratas con función renal normal, observándose una reducción significativa de la expresión renal de Klotho. A continuación, se exploró el efecto de FGF23 en ratas con insuficiencia renal que recibían dietas con diferente contenido en fósforo, de forma que la dieta rica en fósforo incrementó los niveles de FGF23 produciendo aumento de su receptor FGFR1 pero disminución del co-receptor Klotho. Tras administrar un anticuerpo anti- FGF23 (que disminuye los niveles de FGF23), la elevación de la fracción de excreción de fósforo en orina se asoció con una reducción de Klotho, responsabilizando al exceso de fósforo como un elemento clave para promover el descenso de Klotho y el aumento de FGF23. Con estos hallazgos, se planteó posteriormente valorar el efecto del calcitriol como estrategia terapéutica para incrementar los niveles de Klotho. Sin embargo, a pesar de aumentar el fósforo sérico, la expresión de Klotho no descendió. Es decir, el calcitriol evitó la reducción de Klotho inducida por fósforo aunque no consiguió incrementar sus niveles. In vitro, se evaluó el papel de la ruta WNT/β- catenina sobre los niveles de Klotho y ante un exceso de fósforo. Comprobamos que la inhibición de la ruta con Dkk1 (Dickkopf) consiguió aumentar los niveles de Klotho descendidos por el elevado fósforo. Por último, se valoró el efecto de calcitriol en la expresión de Klotho en células HEK-293, observando que calcitriol restablece también aquí la expresión de Klotho in vitro. Por tanto, la existencia de una resistencia a FGF23 promovida por la sobrecarga de fósforo, posibilita que el FGF23 aumente excesivamente mientras que la expresión de Klotho disminuye, causando un descenso en la fosfaturia y promoviendo por tanto la hiperfosfatemia y las posteriores calcificaciones vasculares. Por otro lado, a la vista de estos resultados se realizaron estudios clínicos y experimentales para evaluar en qué medida la elevada ingesta de fósforo y el exceso de fósforo en orina pueden servir como marcadores de progresión renal. A través de los siguientes estudios experimentales realizados pudimos observar que, en estadios tempranos de la ERC, la excesiva carga tubular de fósforo es responsable de estés oxidativo, inflamación y daño renal que contribuye a la progresión de la ERC. De la realización de los estudios clínicos se puede concluir que el ratio fósforo/creatinina podría ser un biomarcador útil para estimar la progresión de la ERC en pacientes con estadios iniciales de la enfermedad. Además encontramos que el ratio fósforo/urea en orina de 24h podría ser un marcador de ingesta de fósforo, por lo que podría ser útil evaluando la progresión de la ERC y como guía para el asesoramiento dietético con el que poder controlar la carga de fósforo en los pacientes con ERC en estadios tempranos de la enfermedad.Chronic kidney disease (CKD) is a prevalent pathology that is associated with mineral bone disease (CKD-MBD), high cardiovascular risk and mortality. Therefore, it is necessary to conduct research aimed at both identifying and preventing the mechanisms of progression of CKD. Serum phosphate increases during impaired renal function and in turn is a risk factor for CKD progression. In contrast, fibroblast growth factor 23 (FGF23) is a phosphaturic hormone that is vital in this context since it is primarily responsible for urinary phosphate excretion. For this reason, the general aim of this thesis is to study the mechanisms that be the cause of resistance to FGF23 and identify a talented biomarker of predicting the progression of CKD. In the beginning we propose animal and in vitro experimental models to determine the mechanisms responsible for the resistance of FGF23. For this, the effect of the administration of recombinant FGF23 in rats with normal renal function was evaluated, and a significant reduction in renal expression of Klotho was observed. Next, the effect of FGF23 in rats with renal insufficiency that received diets with different phosphate content was explored; so that the phosphate-rich diet increased FGF23 levels producing an increase in its receptor FGFR1 but a decrease in the coreceptor Klotho. After anti-FGF23 antibody administration (which lowers FGF23 levels), the elevation of the phosphate excretion fraction in urine was associated with a reduction in Klotho, holding excess phosphate responsible as a key element in promoting drop in Klotho and the increase in FGF23. With these findings, it was subsequently proposed to assess the effect of calcitriol as a therapeutic strategy to increase Klotho levels. However, despite increasing serum phosphate, Klotho's expression did not decrease. That is, calcitriol avoided the reduction phosphate-induced of Klotho although it failed to increase its levels. In vitro, the role of the WNT/β- catenin pathway on Klotho levels and with an excess phosphate was evaluated. We verify that the inhibition of the pathway with Dkk1 (Dickkopf) achieved to increase the levels of descended Klotho by the high phosphate. Finally, the effect of calcitriol on the expression of Klotho in HEK-293 cells was assessed, observing that calcitriol also restores here the expression of Klotho in vitro. Therefore, the existence of a resistance to FGF23, promoted by phosphate overload, makes it possible for FGF23 to increase excessively while Klotho's expression decreases, causing a decrease in phosphaturia and thereby promoting hyperphosphatemia and the subsequent vascular calcifications. Then again, in view of these results, clinical and experimental studies were conducted to assess the extent to which high phosphate intake and excess phosphate in urine can serve as markers of renal progression. Through the following experimental studies we were able to observe that, in the early stages of CKD, the excessive phosphate tubular load is responsible for oxidative stress, inflammation and renal damage that contribute to the progression of CKD. From the results of clinical studies, it can be concluded that the hosphate/creatinine ratio could be a useful biomarker to estimate the progression of CKD in patients with initial stages of the disease. Moreover we found that the 24h urine phosphate/urea ratio could be a marker of phosphate intake, so it could be useful in assessing the progression of CKD and as a guide for dietary advice to control the load phosphate in patients with early stages of CKD

Use of Alternative Wood for the Ageing of Brandy de Jerez

The use of alternative types of wood has arisen for the aging of the Brandy de Jerez, on a pilot plant level. In particular, besides the use of American oak, two more types of oak have been studied, French oak and Spanish oak, allowed by the Technical File for the ID Brandy de Jerez, and chestnut, which, though it is not officially allowed, is a type of wood which had been traditionally used in the area for the aging of wines and distillates. All of them have been studied with different toasting levels: Intense toasting and medium toasting. The study of the total phenolic composition (TPI), chromatic characteristics, organic acids, and sensory analysis have proven that chestnut leads to distillates with a higher amount of phenolic compounds and coloring intensity than oak. This behavior is the opposite as regards the toasting of the wood. Among the different types of oak, Spanish oak produces aged distillates with a higher phenolic composition and a higher color intensity. Regarding tasting, the best-assessed samples were those aged with chestnut, French oak, and American oak, and the assessors preferred those who had used a medium toasting level to those with an intense leve

Efecto agudo de la actividad fisicodeportiva y la expresión corporal sobre el estado de ánimo

Este trabajo analiza los efectos de una sesión de actividad fisicodeportiva y otra de expresión corporal sobre el estado de ánimo en un grupo de 92 adolescentes de la ciudad de Málaga (España), con edades entre los 14 y 16 años (M=14,87; DT= 0,79). En él se sigue una metodología cuasiexperimental con un diseño de tipo pre-post con grupos no equivalentes, en el que existen dos grupos experimentales que han sido sometidos a una sesión de deportes de raqueta y a otra de aeróbic. Se ha utilizado el cuestionario Profile of Mood States (POMS - McNair, Lorr, & Droppleman, 1971) para analizar los siguientes factores: tensión-ansiedad, depresión-melancolía, angustia hostilidad-cólera, vigor-actividad, fatiga-inercia y confusión-orientación. Los resultados indican que, tras la intervención, el estado de ánimo mejora en ambos grupos experimentales, observándose un efecto significativo en aquellos grupos que practican actividad física

Dietary Mg Supplementation Decreases Oxidative Stress, Inflammation, and Vascular Dysfunction in an Experimental Model of Metabolic Syndrome with Renal Failure

whether a dietary Mg supplementation might attenuate vascular dysfunction through the modulation of oxidative stress and inflammation in concurrent MetS and CKD. Methods: A rat model of MetS (Zucker strain) with CKD (5/6 nephrectomy, Nx) was used. Nephrectomized animals were fed a normal 0.1%Mg (MetS+Nx+Mg0.1%) or a supplemented 0.6%Mg (MetS+Nx+Mg0.6%) diet; Sham-operated rats with MetS receiving 0.1%Mg were used as controls. Results: As compared to controls, the MetS+Nx-Mg0.1% group showed a significant increase in oxidative stress and inflammation biomarkers (lipid peroxidation and aortic interleukin-1b and -6 expression) and Endothelin-1 levels, a decrease in nitric oxide and a worsening in uremia and MetS associated pathology as hypertension, and abnormal glucose and lipid profile. Moreover, proteomic evaluation revealed changes mainly related to lipid metabolism and CVD markers. By contrast, in the MetS+Nx+Mg0.6% group, these parameters remained largely similar to controls. Conclusion: In concurrent MetS and CKD, dietary Mg supplementation reduced inflammation and oxidative stress and improved vascular function

Klotho/FGF23 and Wnt Signaling as Important Players in the Comorbidities Associated with Chronic Kidney Disease

Fibroblast Growth Factor 23 (FGF23) and Klotho play an essential role in the regulation of mineral metabolism, and both are altered as a consequence of renal failure. FGF23 increases to augment phosphaturia, which prevents phosphate accumulation at the early stages of chronic kidney disease (CKD). This effect of FGF23 requires the presence of Klotho in the renal tubules. However, Klotho expression is reduced as soon as renal function is starting to fail to generate a state of FGF23 resistance. Changes in these proteins directly affect to other mineral metabolism parameters; they may affect renal function and can produce damage in other organs such as bone, heart, or vessels. Some of the mechanisms responsible for the changes in FGF23 and Klotho levels are related to modifications in the Wnt signaling. This review examines the link between FGF23/Klotho and Wnt/β-catenin in different organs: kidney, heart, and bone. Activation of the canonical Wnt signaling produces changes in FGF23 and Klotho and vice versa; therefore, this pathway emerges as a potential therapeutic target that may help to prevent CKD-associated complications

Papel de la Resonancia Magnética Nuclear en el Diagnóstico de la Cardiopatía Hipertrófica Apical

Hypertrophic cardiomyopathy is a genetic disease with high heterogeneity in different aspects. One of its little-known forms is apical hypertrophic cardiomyopathy, which is characterized by an almost exclusive involvement of the left ventricular apex, and is distinguished by the ace-of-spades morphology on ventriculography. The ECG is a diagnostic method for this pathology but different non-invasive diagnostic methods such as cardiac magnetic resonance allow us to confirm its diagnosis due to its greater resolution and appreciation of cardiac morphology. We performed a bibliographic search of articles in English and Spanish with different descriptors, which resulted in the discovery of different case reports that highlight the role of cardiac magnetic resonance as a very useful diagnostic method in apical hypertrophic cardiomyopathy. Therefore, imaging methods such as magnetic resonance play a crucial role in the identification of morphological characteristics and in the evaluation of complications associated with this pathology.La miocardiopatía hipertrófica es una enfermedad genética con una alta heterogeneidad en diferentes aspectos. Una de sus formas poco conocidas es la miocardiopatía hipertrófica apical la cual se caracteriza por un compromiso, casi exclusivo, del ápice ventricular izquierdo, y se distingue por la morfología de as de picas en la ventriculografía. El ECG es un método diagnóstico para dicha patología pero diferentes métodos diagnósticos no invasivos como la resonancia magnética cardíaca nos permite confirmar su diagnóstico debido  a su mayor resolución y apreciación de la morfología cardiaca. Realizamos una búsqueda bibliográfica de artículos en inglés y español con distintos descriptores lo cual dio como resultado el hallazgo de diferentes reportes de casos en los que se destacan el papel de la resonancia magnética cardiaca como método de diagnóstico de gran utilidad en la miocardiopatía hipertrófica apical. Por ello, los métodos de imagen como la resonancia magnética, desempeñan un papel crucial en la identificación de las características morfológicas y en la evaluación de las complicaciones asociadas a esta patologí

The direct effect of fibroblast growth factor 23 on vascular smooth muscle cell phenotype and function

[Background] In chronic kidney disease (CKD) patients, increased levels of fibroblast growth factor 23 (FGF23) are associated with cardiovascular mortality. The relationship between FGF23 and heart hypertrophy has been documented, however, it is not known whether FGF23 has an effect on vasculature. Vascular smooth muscle cells VSMCs may exhibit different phenotypes; our hypothesis is that FGF23 favours a switch from a contractile to synthetic phenotype that may cause vascular dysfunction. Our objective was to determine whether FGF23 may directly control a change in VSMC phenotype.[Methods] This study includes in vitro, in vivo and ex vivo experiments and evaluation of patients with CKD stages 2–3 studying a relationship between FGF23 and vascular dysfunction.[Results] In vitro studies show that high levels of FGF23, by acting on its specific receptor FGFR1 and Erk1/2, causes a change in the phenotype of VSMCs from contractile to synthetic. This change is mediated by a downregulation of miR-221/222, which augments the expression of MAP3K2 and PAK1. miR-221/222 transfections recovered the contractile phenotype of VSMCs. Infusion of recombinant FGF23 to rats increased vascular wall thickness, with VSMCs showing a synthetic phenotype with a reduction of miR-221 expression. Ex-vivo studies on aortic rings demonstrate also that high FGF23 increases arterial stiffening. In CKD 2–3 patients, elevation of FGF23 was associated with increased pulse wave velocity and reduced plasma levels of miR-221/222.[Conclusion] In VSMCs, high levels of FGF23, through the downregulation of miR-221/222, causes a change to a synthetic phenotype. This change in VSMCs increases arterial stiffening and impairs vascular function, which might ultimately worsen cardiovascular disease.This work was supported by a Spanish government grant from the Programa Nacional I+D+I 2013–2016 and Instituto de Salud Carlos III (ISCIII) grants PI18/0138 and PI21/0654 co-financing from European Funds (FEDER), Consejería de Salud (grants PI-0136 and PI-0169-2020) from the Junta de Andalucía, Framework Programme 7 Syskid UE grant FP7-241544, and EUTOX and REDinREN from the ISCIII. N.V. and J.M.D.-T. were supported by Consejería de Economía, Innovación, Ciencia y Empleo (grant CVI-7925) from the Junta de Andalucía. Y.A. and J.R.M.-C. are senior researchers supported by the Nicolás Monardes Programme, Consejería de Salud-Servicio Andaluz de Salud (Junta de Andalucía).Peer reviewe

Supplemental Material The direct effect of fibroblast growth factor 23 on vascular smooth muscle cell phenotype and function

3 pages. -- Figure S1. Supplemental Material. Effects of anti-miR-221 and miR-222. -- Figure S1. Supplemental Material: A) Anti-miR-221 and B) anti-miR-222 transfection for 48 h decreased not significantly the expression of miR-221 and miR-222 in VSMC. -- Figure S2. Supplemental Material. Recombinant Klotho administration did not modify the expression of contractile markers of VSMC. -- Figure S3. Histological quantifications in thoracic aortas of rats of synthetic markers of VSMC.Peer reviewe

Resultados de la Vigilancia Epidemiológica de las enfermedades transmisibles. Informe anual. Año 2015

El objetivo final de la vigilancia de las enfermedades transmisibles es reducir su incidencia en la comunidad. La Red Nacional de Vigilancia Epidemiológica (RENAVE) tiene entre sus funciones la recogida sistemática de la información epidemiológica, su análisis e interpretación y la difusión de los resultados. Este informe presenta los resultados de la vigilancia de las enfermedades transmisibles para el año 2015 realizada por los servicios de vigilancia de las comunidades autónomas y el Centro Nacional de Epidemiología (CNE) de acuerdo a los protocolos de la RENAVE.N