Regulación de la formación de especies reactivas de oxígeno por la cadena respiratoria mitocondrial en células neurales

[ES]Para conocer la función fisiológica de las especies reactivas de oxígeno (ROS) en cerebro, es necesario analizar la contribución de los diferentes tipos de células neurales en la formación de ROS. En la Tesis Doctoral hemos evaluado la capacidad de las neuronas y astrocitos de generar ROS de forma espontánea. Hemos observado que la producción de ROS es mayor (desde 1.5 a 10 veces) en astrocitos que en neuronas, en cultivos primarios de ratas Wistar y ratones C57BL6, con independencia de las condiciones de cultivo y el método de determinación de ROS. Las diferencias en la producción de ROS se confirmó a partir de neuronas y astrocitos diseccionadas de ratones adultos C57BL6, sugiriendo fuertemente que se trata de un fenómeno conservado in vivo. Además, las diferencias en la producción de ROS entre neuronas y astrocitos presenta un origen mitocondrial. Para conocer el mecanismo responsable de las diferencias en la producción mitocondrial de ROS (mROS), hemos analizado el ensamblaje de la cadena respiratoria mitocondrial. Usando electroforesis nativas, análisis proteómicos, y transferencia tipo Western, hemos observado que, en astrocitos, una gran proporción del complejo I se encuentra libre, mientras que en neuronas la mayor parte se encuentra formando parte de supercomplejos. Además, la abundancia de la subunidad del complejo I NDUFS1, en el complejo I libre, es menor en astrocitos que en neuronas. La sobreexpresión de NDUFS1 en astrocitos incrementó la proporción del complejo I en supercomplejos, reduciendo la producción de mROS. Por el contrario, el silenciamiento de NDUFS1 en neuronas disminuyó la proporción del complejo I en supercomplejos, incrementando la producción de mROS. Además, hemos observado que la reducción de los niveles de ROS en astrocitos, tras la incubación con GSH-etil éster, estabilizó al complejo I e incrementó su ensamblaje en supercomplejos. Finalmente, la reducción de mROS en astrocitos, por la expresión de una forma mitocondrial de la catalasa (mitoCatalasa), disminuyó la actividad de NRF2, y la estabilidad de HIF1. Por tanto, estos resultados son los primeros en demostrar como la modulación del complejo I en supercomplejos regula la producción mitocondrial de ROS en un sistema biológico intacto. Además, este mecanismo explica las diferencias intrínsecas en la producción de ROS entre neuronas y astrocitos, posiblemente ejerciendo un papel señalizador sobre las funciones fisiológicas

Bayesian approach to urinary ESBL-producing Escherichia coli

This is a retrospective study about the prevalence of ESBL-producing Escherichia coli (EEC) in urinary specimens from patients from the Comunitat Valenciana from January 2007 to December 2008. Data were retrieved from RedMIVA, and Bayesian generalized linear mixed models were considered to study the prevalence of EEC with regard to demographical and microbiological factors. The total number of infections considered was 164,502, the amount of urinary isolates was 70,827 belonging to 49,304 different patients, and 5,161 (7.3%) of the urinary isolates were EEC. Three out of four E. coli were isolated in women (76.8%), men showed higher rates of EEC (9.7% in men vs. 6.5% in women). EEC patients were, in average, 10.8 years older, and hospitalization was more frequent (9.9% vs. 6.9%). Resistance to non-β-lactams antimicrobials was higher in EEC. The rates of ciprofloxacin and co-trimoxazol resistance in EEC were 75.5% and 52.0%, respectively, whereas it ranged between 1.4-12.4% for the rest of antimicrobials.Prior EEC infection and hospitalization were the most relevant risk factors and increased the expected EEC probability approximately 400% and 50% respectively. Other infections played an important and positive role too, Enterobacteriaceae, P. aeruginosa and other bacteria being the most relevant elements. Female gender was a protective factor and reduced the risk by approximately 25% while age was an additive risk factor. Finally, an open-access web-based software was constructed to compute the probability that an E. coli in a urinary infection be an EEC from a specific combination of risk factors. This pharmacovigilance tool should prove useful to monitor and control antimicrobial resistance spread

Abrogating mitochondrial ROS in neurons or astrocytes reveals cell-specific impact on mouse behaviour

Article 101917, (2021)[EN]Cells naturally produce mitochondrial reactive oxygen species (mROS), but the in vivo pathophysiological significance has long remained controversial. Within the brain, astrocyte-derived mROS physiologically regulate behaviour and are produced at one order of magnitude faster than in neurons. However, whether neuronal mROS abundance differentially impacts on behaviour is unknown. To address this, we engineered genetically modified mice to down modulate mROS levels in neurons in vivo. Whilst no alterations in motor coordination were observed by down modulating mROS in neurons under healthy conditions, it prevented the motor discoordination caused by the pro-oxidant neurotoxin, 3-nitropropionic acid (3-NP). In contrast, abrogation of mROS in astrocytes showed no beneficial effect against the 3-NP insult. These data indicate that the impact of modifying mROS production on mouse behaviour critically depends on the specific cell-type where they are generated

Recovering ancient grapevine cultivars in the Spanish provinces of Alicante and Valencia

[EN] The provinces of Alicante and Valencia, located on the Mediterranean coast of Spain, have been important viticulture areas since historical times. In the context of the research project CGL2015-70843-R, we initiated different approaches in order to recover ancient cultivars threatened with disappearance, and we developed in-vitro protocols for virus sanitation and in-vitro conservation of the recovered germplasm. Among the historic cultivars, we localized several accessions of cultivars that were commonly grown in the pre-phylloxera era in the provinces of Alicante and Valencia (`Valencí blanc¿, `Valencí negre¿, `Planta Mula¿, `Botó de Gall¿ and `Raïm del Clotet¿). Microsatellite profiles were obtained to confirm or identify the surveyed germplasm, and genetic variability was observed. In addition, a survey was carried out covering the main area of `Monastrell¿ cultivation in the Vinos de Alicante Protected Designation of Origin. This ancient cultivar, also known as `Mourvèdre¿, is cultivated mainly in the southeast of Spain, and is highly adapted to the dry and warm climate of this area. Genotyping by sequencing (GBS) was used to estimate its genetic diversity, and high variability was found. This analysis will provide a large number of high-quality single-nucleotide polymorphisms (SNPs), well distributed across the genome, suitable for genotyping of clones, which will allow the design of strategies to optimize their conservation and use.This study was supported by the project PRPCGL2015-70843-R co-funded with FEDER Funds, and by the Cátedra Cajamar de Economía y Desarrollo Agroambiental de la UMH. We thank Julio García (Consellería de Agricultura, Medio Ambiente, Cambio Climático, y Desarrollo Rural, GVA, Jaume Soler (Botánica Mediterránea SL) and Antonio Olmos (IVIA) for their collaboration in our project.Yuste Del Carmen, A.; Martínez-Gil, F.; García-Martínez, S.; López-Lluch, D.; Peiró Barber, RM.; Jiménez, C.; Ruiz, J.... (2019). Recovering ancient grapevine cultivars in the Spanish provinces of Alicante and Valencia. Acta Horticulturae. (1248):43-46. https://doi.org/10.17660/ActaHortic.2019.1248.6S4346124

Essentiality of fatty acid synthase in the 2D to anchorage-independent growth transition in transforming cells

Upregulation of fatty acid synthase (FASN) is a common event in cancer, although its mechanistic and potential therapeutic roles are not completely understood. In this study, we establish a key role of FASN during transformation. FASN is required for eliciting the anaplerotic shift of the Krebs cycle observed in cancer cells. However, its main role is to consume acetyl-CoA, which unlocks isocitrate dehydrogenase (IDH)-dependent reductive carboxylation, producing the reductive power necessary to quench reactive oxygen species (ROS) originated during the switch from two-dimensional (2D) to three-dimensional (3D) growth (a necessary hallmark of cancer). Upregulation of FASN elicits the 2D-to-3D switch; however, FASN's synthetic product palmitate is dispensable for this process since cells satisfy their fatty acid requirements from the media. In vivo, genetic deletion or pharmacologic inhibition of FASN before oncogenic activation prevents tumor development and invasive growth. These results render FASN as a potential target for cancer prevention studies.M.Q.F. is a recipient of the following grants: FIS PI13/00430 and FIS PI16/00354 funded by the Instituto de Salud Carlos III (ISCIII) and co-funded by the European Regional Development Fund (ERDF) and AECC Scientific Foundation (Beca de Retorno 2010). R.C. is a recipient of the following grants: FIS PI11/00832 and FIS PI14/00726 funded by the Instituto de Salud Carlos III (ISCIII) and co-funded by the European Regional Development Fund (ERDF), II14/00009 and PIE15/00068 from the Ministerio de Sanidad, Spain. N.S.C. is a recipient of an NIH grant (5R35CA197532). O.Y.T. is a recipient of the grants BFU2014-57466 from the Ministerio de Economia y Competitividad (MINECO). J.P.B. is funded by MINECO (SAF2016-78114-R), Instituto de Salud Carlos III (RD12/0043/0021), Junta de Castilla y Leon (Escalera de Excelencia CLU-2017-03), Ayudas Equipos Investigacion Biomedicina 2017 Fundacion BBVA, and Fundacion Ramon Areces. This study was partially supported by the generous donations from Fundacion CRIS Contra el Cancer and AVON Spain. We thank Drs. Erwin Wagner and Nabil Djouder for their critical review of the paper.S

In vitro propagation of Vitis vinifera L. cv. 'Monastrell'

[EN] Background: A protocol for the micropropagation of the grape (Vitis vinifera L.) cultivar 'Monastrell' was developed. Initial plant material was obtained from the sanitary selection of grapevine plants performed by real-time RT-PCR to confirm the absence of Grapevine fanleaf virus, Arabis mosaic virus, Grapevine leafroll-associated virus 1, Grapevine leafroll-associated virus 3, and Grapevine fleck virus. Results: The effects of the salt composition (comparing Lloyd and McCown woody plant medium and Murashige and Skoog medium 1/2 macronutrients) and the growth regulator benzylaminopurine (BAP), at 0 and 8.9 mu M, on plant propagation were evaluated using nodes as explants. The most efficient procedure consisted of bud induction in the medium with Lloyd and McCown woody plant salts and 8.9 mu M BAP for 30 d along with elongation in cytokinin-free medium for 60 d, which gave 22 nodes/explant (174 plants/initial plant). A second cycle of propagation in a medium without BAP for another 60 d could give approximately 10,000 nodes, which can be obtained after an additional 2 months of culture. All plants acclimatized after the second cycle of multiplication were successfully transferred to soil. Conclusion: We developed an optimal protocol for V. vinifera cv. 'Monastrell' micropropagation, the first described for this cultivar. (C) 2017 Pontificia Universidad Catolica de Valparaiso. Production and hosting by Elsevier B. V. All rights reserved.The study was supported by the projects RTA2011-00067-C04, RTA2014-00061-C03, and PRP-CGL2015-70843-R, all co-funded with FEDER Funds. Tania San Pedro has a grant (01/14-FSE-22) supported by the Instituto Valenciano de Investigaciones Agrarias.San Pedro-Galan, T.; Peiró Barber, RM.; Villanova, J.; Olmos Castelló, A.; Gisbert Domenech, MC. (2017). In vitro propagation of Vitis vinifera L. cv. 'Monastrell'. Electronic Journal of Biotechnology. 27:80-83. https://doi.org/10.1016/j.ejbt.2017.03.006S80832

Repurposing of tamoxifen ameliorates CLN3 and CLN7 disease phenotype

Batten diseases (BDs) are a group of lysosomal storage disorders characterized by seizure, visual loss, and cognitive and motor deterioration. We discovered increased levels of globotriaosylceramide (Gb3) in cellular and murine models of CLN3 and CLN7 diseases and used fluorescent-conjugated bacterial toxins to label Gb3 to develop a cell-based high content imaging (HCI) screening assay for the repurposing of FDA-approved compounds able to reduce this accumulation within BD cells. We found that tamoxifen reduced the lysosomal accumulation of Gb3 in CLN3 and CLN7 cell models, including neuronal progenitor cells (NPCs) from CLN7 patient-derived induced pluripotent stem cells (iPSC). Here, tamoxifen exerts its action through a mechanism that involves activation of the transcription factor EB (TFEB), a master gene of lysosomal function and autophagy. In vivo administration of tamoxifen to the CLN7Δex2 mouse model reduced the accumulation of Gb3 and SCMAS, decreased neuroinflammation, and improved motor coordination. These data strongly suggest that tamoxifen may be a suitable drug to treat some types of Batten disease.This work was funded by the European Union’s Horizon 2020 research and innovation programme (BATCure, grant No. 666918 to DLM, JPB, SEM, TB and SS). JPB is funded by the Agencia Estatal de Investigación (PID2019-105699RB-I00/ AEI / 10.13039/501100011033 and RED2018-102576-T), Plan Nacional sobre Drogas (2020I028), Junta de Castilla y León (Escalera de Excelencia CLU-2017-03), Ayudas Equipos Investigación Biomedicina 2017 Fundación BBVA and Fundación Ramón Areces. SS was funded by a grant from the Mila’s Miracle Foundation. TB was supported by German Research Council (DFG) grant FOR2625. SM benefits from MRC funding to the MRC Laboratory for Molecular Cell Biology University Unit at UCL (award code MC_U12266B) towards laboratory and office space. We acknowledge Marcella Cesana for providing the TFEB virus. Graphical abstract was created using BioRender.com

Aberrant upregulation of the glycolytic enzyme PFKFB3 in CLN7 neuronal ceroid lipofuscinosis

CLN7 neuronal ceroid lipofuscinosis is an inherited lysosomal storage neurodegenerative disease highly prevalent in children. CLN7/MFSD8 gene encodes a lysosomal membrane glycoprotein, but the biochemical processes affected by CLN7-loss of function are unexplored thus preventing development of potential treatments. Here, we found, in the Cln7∆ex2 mouse model of CLN7 disease, that failure in autophagy causes accumulation of structurally and bioenergetically impaired neuronal mitochondria. In vivo genetic approach reveals elevated mitochondrial reactive oxygen species (mROS) in Cln7∆ex2 neurons that mediates glycolytic enzyme PFKFB3 activation and contributes to CLN7 pathogenesis. Mechanistically, mROS sustains a signaling cascade leading to protein stabilization of PFKFB3, normally unstable in healthy neurons. Administration of the highly selective PFKFB3 inhibitor AZ67 in Cln7∆ex2 mouse brain in vivo and in CLN7 patients-derived cells rectifies key disease hallmarks. Thus, aberrant upregulation of the glycolytic enzyme PFKFB3 in neurons may contribute to CLN7 pathogenesis and targeting PFKFB3 could alleviate this and other lysosomal storage diseases.This work was funded by the European Regional Development Fund, European Union’s Horizon 2020 Research and Innovation Programme (BATCure grant No. 666918 to J.P.B., S.E.M., D.L.M., S.S., and T.R.M.; PANA grant No. 686009 to A.A.), Agencia Estatal de Investigación (PID2019-105699RB-I00/AEI/10.13039/501100011033 and RED2018‐102576‐T to J.P.B.; SAF2017-90794-REDT to A.A.), Instituto de Salud Carlos III (CB16/10/00282 to J.P.B.; PI18/00285; RD16/0019/0018 to A.A.), Junta de Castilla y León (CS/151P20 and Escalera de Excelencia CLU-2017-03 to J.P.B. and A.A.), Ayudas Equipos Investigación Biomedicina 2017 Fundación BBVA (to J.P.B.), and Fundación Ramón Areces (to J.P.B. and A.A.). SM benefits from MRC funding to the MRC Laboratory for Molecular Cell Biology University Unit at UCL (award code MC_U12266B) towards lab and office space. Part of this work was funded by Gero Discovery L.L.C. M.G.M. is an ISCIII-Sara Borrel contract recipient (CD18/00203)

Aberrant upregulation of glycolysis mediates CLN7 neuronal ceroid lipofuscinosis

Resumen del trabajo presentado en el 43rd Annual Meeting of the Spanish Society of Biochemistry & Molecular Biology, celebrado en Barcelona, del 19 al 22 de julio de 2021CLN7 neuronal ceroid lipofuscinosis is an inherited lysosomal storage neurodegenerative disease highly prevalent in children. CLN7/MFSD8 gene encodes a lysosomal membrane glycoprotein, but the biochemical processes affected by CLN7-loss of function are unexplored thus preventing development of potential treatments. Here, we found, in the Cln7∆ex2 mouse model of CLN7 disease, that failure in the autophagy-lysosomal pathway causes accumulation of structurally and bioenergetically impaired neuronal mi- tochondria. In vivo genetic approach revealed elevated mitochondrial reactive oxygen species (mROS) in Cln7∆ex2 neurons that mediates glycolysis activation and contributes to CLN7 pathogenesis. Mechanistically, mROS sustains a signaling cascade leading to protein stabilization of PFK- FB3, a glycolytic-promoting enzyme normally unstable in healthy neurons. Pharmacological inhibition of PFKFB3 in Cln7∆ex2 mouse brain in vivo and in CLN7 patients-derived cells rectified key disease hallmarks. Thus, aberrant upregulation of neuronal glycolysis contributes to CLN7 patho-genesis and targeting PFKFB3 may alleviate this and other lysosomal storage diseasesThis work was funded by Agencia Estatal de Investigación (PID2019-105699RB-I00).Peer reviewe