Modulación de la adaptación a estrés por el metabolismo respiratorio y el envejecimiento

[ES] Las células eucariotas se adaptan continuamente a estreses abióticos como por ejemplo el estrés osmótico o el estrés oxidativo. Ambos estreses están fisiológicamente relacionados, y en estudios anteriores se ha podido establecer que una eficiente adaptación al estrés hiperosmótico y salino requiere una activación del metabolismo respiratorio a través de la inducción de la función mitocondrial y peroxisomal. En el presente trabajo se estudiará cómo influye la función de los dos orgánulos y el proceso del envejecimiento en la dinámica adaptación a estrés. Para ello, se plantean tres abordajes experimentales usando la levadura Saccharomyces cerevisiae como modelo celular. 1- Se determinará cómo influye la función mitocondrial y peroxisomal en la respuesta dosis dependiente de la expresión génica a estrés osmótico. Se emplearán cepas transformadas con reporteros de luciferasa desestabilizada específicos para dicho estrés. Se cuantificará en tiempo real la capacidad de dosis respuesta de cada cepa y se comparará de forma cuantitativa la sensibilidad y posibles defectos de señalización entre las cepas sin y con mutaciones mitocondriales o peroxisomales. 2- Peroxisomas y mitocondrias están conectados físicamente por proteínas de la membrana exterior de los dos orgánulos, como Pex11 y Mdm34 en levadura. Previos estudios han mostrado que el número de peroxisomas asociados a la red mitocondrial aumenta en situaciones de estrés salino. En el presente trabajo se cuantificará el grado de asociación entre los dos orgánulos por microscopía de fluorescencia. Se usarán cepas modificadas con fusiones de Pex11 y Mdm34 con los dominios N- y C-terminales de YFP en ensayos de BiFC in vivo (complementación bimolecular de fluorescencia). Se cuantificará así la interacción de mitocondrias y peroxisomas durante la inducción de la respiración y la adaptación a estrés. 3- Se estudiará cómo influye el envejecimiento de las células en su capacidad de activar la expresión génica en respuesta a estrés oxidativo. Una característica clave de las células envejecidas es la acumulación de daños oxidativos intracelulares y una menor capacidad de detoxificar ROS. Se estudiará en dos modelos diferentes del envejecimiento de levadura, el replicativo y el cronológico, cómo cambia la capacidad de defensa ante el estrés oxidativo durante el proceso del envejecimiento. Se emplearán cepas con reporteros luciferasa integrativos y específicos para el estrés oxidativo en estudios de la expresión génica en tiempo real y a lo largo de los diferentes regímenes de envejecimiento.[EN] Eukaryotic cells continuously adapt to abiotic stresses such as osmotic or oxidative stress. Both stresses are physiologically related, and in previous studies it has been established that an efficient adaptation to hyperosmotic and saline stress requires an activation of respiratory metabolism through the induction of mitochondrial and peroxisomal function. In the present work we study how the function of the two organelles and the aging process influences the dynamic adaptation to stress. Three experimental approaches are proposed using the yeast Saccharomyces cerevisiae as a cellular model. 1- It will be determined how mitochondrial and peroxisomal function influences the dosedependent response of gene expression to osmotic stress. Strains transformed with destabilized luciferase reporters will be used. The dose response capacity of each strain will be quantified in real time and the sensitivity and possible signaling defects between the strains without and with mitochondrial or peroxisomal mutations will be quantitatively compared. 2- Peroxisomes and mitochondria are physically connected by proteins of the outer membrane of the two organelles, for example Pex11 and Mdm34 in yeast. Previous studies have shown that the number of peroxisomes associated with the mitochondrial network increases in situations of salt stress. In the present work, the degree of association between the two organelles will be quantified by fluorescence microscopy. Strains modified with Pex11 and Mdm34 fusions with the N- and C-terminal domains of YFP will be used in BiFC assays in vivo (bimolecular fluorescence complementation). The interaction of mitochondria and peroxisomes during the induction of respiration and adaptation to stress will be quantified. 3- It will be studied how the aging of cells influences their ability to activate gene expression in response to oxidative stress. A key feature of aging cells is the accumulation of intracellular oxidative damage and a decreased ability to detoxify ROS. We will study in two different models of yeast aging, the replicative and the chronological, how the defense capacity changes in response to oxidative stress during the aging process. Strains with integrative and specific luciferase reporters for oxidative stress will be used in studies of gene expression in real time and throughout the different aging regimes.González Cantó, E. (2018). Modulación de la adaptación a estrés por el metabolismo respiratorio y el envejecimiento. http://hdl.handle.net/10251/107596TFG

Dose dependent gene expression is dynamically modulated by the history, physiology and age of yeast cells

[EN] Cells respond to external stimuli with transient gene expression changes in order to adapt to environmental alterations. However, the dose response profile of gene induction upon a given stress depends on many intrinsic and extrinsic factors. Here we show that the accurate quantification of dose dependent gene expression by live cell luciferase reporters reveals fundamental insights into stress signaling. We make the following discoveries applying this non-invasive reporter technology. (1) Signal transduction sensitivities can be compared and we apply this here to salt, oxidative and xenobiotic stress responsive transcription factors. (2) Stress signaling depends on where and how the damage is generated within the cell. Specifically we show that two ROS-generating agents, menadione and hydrogen peroxide, differ in their dependence on mitochondrial respiration. (3) Stress signaling is conditioned by the cells history. We demonstrate here that positive memory or an acquired resistance towards oxidative stress is induced dependent on the nature of the previous stress experience. (4) The metabolic state of the cell impinges on the sensitivity of stress signaling. This is shown here for the shift towards higher stress doses of the response profile for yeast cells moved from complex to synthetic medium. (5) The age of the cell conditions its transcriptional response capacity, which is demonstrated by the changes of the dose response to oxidative stress during both replicative and chronological aging. We conclude that capturing dose dependent gene expression in real time will be of invaluable help to understand stress signaling and its dynamic modulation.The authors thank Daniel E. Gottschling (Fred Hutchinson Cancer Research Center, Seattle, US) for the kind gift of MEP yeast strain UCC4925. This work was supported by the Ministerio de Economia y Competitividad (grant number BFU2016-75792-R).Pascual-Ahuir Giner, MD.; González-Cantó, E.; Juyoux, P.; Pable, J.; Poveda-Huertes, D.; Saiz-Balbastre Sandra; Squeo, S.... (2019). Dose dependent gene expression is dynamically modulated by the history, physiology and age of yeast cells. Biochimica et Biophysica Acta (BBA) - Gene Regulatory Mechanisms. 1862(4):457-471. https://doi.org/10.1016/j.bbagrm.2019.02.009S4574711862

Increased levels of NETosis biomarkers in high-grade serous ovarian cancer patients’ biofluids: Potential role in disease diagnosis and management

Introduction: High-grade serous ovarian cancer (HGSOC) is the second most frequent gynecological malignancy but the most lethal, partially due to the spread of the disease through the peritoneal cavity. Recent evidence has shown that, apart from their role in immune defense through phagocytosis and degranulation, neutrophils are able to participate in cancer progression through the release of neutrophil extracellular traps (NETs) in a process called NETosis. NETs are composed of DNA, histones, calprotectin, myeloperoxidase (MPO) and elastase and the NETosis process has been proposed as a pre-requisite for the establishment of omental metastases in early stages of HGSOC. Nevertheless, its role in advanced stages remains to be elucidated. Therefore, our principal aim is to characterize a NETosis biomarker profile in biofluids from patients with advanced HGSOC and control women. Methods: Specifically, five biomarkers of NETosis (cell-free DNA (cfDNA), nucleosomes, citrullinated histone 3 (citH3), calprotectin and MPO) were quantified in plasma and peritoneal fluid (PF) samples from patients (n=45) and control women (n=40). Results: Our results showed that HGSOC patients presented a higher concentration of cfDNA, citH3 and calprotectin in plasma and of all five NETosis biomarkers in PF than control women. Moreover, these biomarkers showed a strong ability to differentiate the two clinical groups. Interestingly, neoadjuvant treatment (NT) seemed to reduce NETosis biomarkers mainly systemically (plasma) compared to the tumor environment (PF). Discussion: In conclusion, NETosis biomarkers are present in the tumor environment of patients with advanced HGSOC, which might contribute to the progression of the disease. Besides, plasma cfDNA and calprotectin could represent minimally invasive surrogate biomarkers for HGSOC. Finally, NT modifies NETosis biomarkers levels mainly at the systemic level

Special Issue “miRNAs in the Era of Personalized Medicine: From Biomarkers to Therapeutics 2.0”

Personalized medicine has become a new paradigm in the management of a variety of diseases [...

Special Issue “miRNAs in the Era of Personalized Medicine: From Biomarkers to Therapeutics 2.0”

Personalized medicine has become a new paradigm in the management of a variety of diseases [...

miRNAs in the Era of Personalized Medicine: From Biomarkers to Therapeutics

In recent years, interest in personalized medicine has considerably increased [...

Toward an improved assessment of quality of life in endometriosis: evaluation of the Spanish version of the Endometriosis Health Profile 30

Purpose Our main objective is to evaluate the psychometric properties of the Spanish version of the EHP-30 questionnaire. The secondary aim is to evaluate the differences in the scores of the core EHP-30 scales between patients with either surgical treatment or conservative management of endometriosis. Methods Cross-sectional study conducted into a tertiary hospital endometriosis reference unit. All patients (n = 223) pre-surgically completed the core EHP-30 questionnaire, the EQ-5D questionnaire (n = 184) and a visual analogue scale (n = 210) for endometriosis-related pain. Demographical and clinical data were recorded. Results Psychometric characteristics of the Spanish core EHP-30 questionnaire were investigated. Statistical analyses confirmed the five-structure factor, a high degree of internal consistency and of item-total correlation for all the assessed items. Convergent validity between EQ-5D and EHP-30 items and between VAS and EHP-30 subscale pain was observed. Additionally, patients with surgical management rendered significantly higher scores in the core EHP-30 subscales “pain” and “control and powerlessness”. Conclusions We present the reliability, validity and acceptability of the Spanish core EHP-30 questionnaire, providing clinicians and researchers with an improved tool to assess the endometriosis-related quality of life. Additionally, we show that patients subsidiaries of surgical treatment for endometriosis present with higher pain and powerlessness than those with conservative management

New Roles for Old Friends: Involvement of the Innate Immune System in Tumor Progression

The association between the immune system and tumor progression has attracted much interest in the research community in recent years [...

Tools for the internationalization of educational material in the University: the case of micro-videos on biodiversity at the UCM

Este proyecto inicia la universalización de material educativo audiovisual a partir de ofertar micro-videos en ingles sobre la biodiversidad dirigidos a los diferentes componentes de la comunidad educativa internacional.This project initiates the universalization of audiovisual educational material from offering micro-videos in English on biodiversity aimed at the different components of the international educational community.Depto. de Biodiversidad, Ecología y EvoluciónFac. de Ciencias BiológicasFALSEsubmitte