Synaptic frailty and mitochondrial dysfunction in familial amyotrophic lateral sclerosis

L’Esclerosi Lateral Amiotròfica (ELA) és una malaltia neurodegenerativa de la motoneurona. Totes les neurones del sistema motor es veuen afectades pel flux degeneratiu en aquesta malaltia des de l’escorça motora primària fins a la junta neuromuscular. Al 1993, la descoberta de mutacions en el gen SOD1 va obrir nous horitzons experimentals amb la creació dels primers rosegadors transgènics per aquesta malaltia. Des d’aquell moment i fins a l’actualitat la mutació més estudiada en l’ELA ha estat la SOD1-G93A a tot el món. Els models transgènics per aquesta mutació de la SOD1 han revelat mecanismes essencials de la neurodegeneració en aquesta malaltia incloent l’excitotoxicitat, la disfunció proteica i la degeneració axosinàptica entre altres. En aquest treball hem explorat els canvis moleculars que tenen lloc als terminals-C, uns terminals molt especialitzats en les α-moto neurones, dels rosegadors transgènics SOD1-G93A. A més, també hem focalitzat la nostra atenció a la relació patològica que s’estableix en l’ELA familiar (ELAF) entre la mutació SOD1-G93A i les mitocòndries de les motoneurones. En relació als terminals C en moto neurones durant la ELAF, hem trobat canvis associats a l’aparició dels símptomes com ara expressió incrementada del factor neurotròfic Neuregulina-1 localitzat també per primer cop a la cisterna subsinàptica dels terminals C aposats a les α-moto neurones. La Neuregulina-1 en aquestes estructures de reticle endoplasmàtic va ser observada a dins de vesícules extracel·lulars (VEs), suggerint que l’anàlisi de la Neuregulina-1 en VEs durant ELA és especialment prometedor com a biomarcador potencial en aquesta malaltia. Així nosaltres hem desenvolupat també un nou mètode per tal d’aïllar VEs, donat que aquest és un pas essencial previ a l’estudi de les proteïnes associades amb aquestes estructures. El nostre mètode aplicat a la purificació de VEs en teixits complexos fou capaç de facilitar la identificació de la Neuregulina-1 en VEs provinents de teixits clínics i fluids biològics. En relació a les implicacions de la mitocòndria en la ELA, hem trobat que la mutació SOD1-G93A estabilitza la proteïna PINK1 a la mitocòndria seguidament activant el factor nuclear NFκB en neurones. La interacció seqüencial entre la SOD1 mutant i NFκB crea una clara disfunció en la capacitat proteolítica del proteosoma, el qual promou coagregació de la SOD1 mutant i el PINK1 en aquestes cèl·lules. Aquests resultats afegeixen un substancial coneixement mecanístic sobre els rols de la mitocòndria en els events neurodegeneratius clàssics de l’ELA, com ara en l’agregació de proteïnes disfuncionals en moto neurones. Seguint el nostre estudi de l’afectació mitocondrial en la ELA, hem creat i caracteritzat un nou model de Drosophila que expressa la mutació humana SOD1-G93A exclusivament en fibres musculars toràciques sota el promotor 24B. Aquest model de Drosophila transgènica recapitula amb èxit el fenotip mitocondrial prèviament observat de l’ELA presentant importants avantatges sobretot en l’elecció de nous compostos terapèutics. En definitiva, els resultats generats en aquesta tesi proporcionen evidència experimental, extensa comprensió molecular i insinuen nous horitzons terapèutics sobre els mecanismes moleculars i els events neurodegeneratius associats a la disfunció sinàptica i mitocondrial en l’ELAF.La Esclerosis Lateral Amiotrófica (ELA) es una enfermedad neurodegenerativa de la motoneurona. Todas las motoneuronas se ven afectadas desde la corteza motora primaria hasta la unión neuromuscular. En 1993 la descubierta de mutaciones en el gen SOD1 abrió nuevos límites experimentales con la creación de los primeros roedores transgénicos para esta enfermedad. Desde ese momento y hasta la actualidad, la mutación más estudiada en la ELA ha sido la mutación SOD1-G93A. Los modelos transgénicos de esta mutación han revelado mecanismos esenciales de la neurodegeneración en la ELA, incluyendo la excitotoxicidad, la disfunción proteica y la degeneración axosináptica entre otras. En este trabajo hemos explorado los cambios moleculares que tienen lugar en los terminales C, unos terminales altamente especializados de las α-motoneuronas, en un modelo murino de ELA con la mutación SOD1-G93A. Además, también hemos focalizado nuestra atención sobre la relación patológica que se establece en la ELA familiar (ELAF) entre la mutación SOD1-G93A y las mitocondrias. En relación a los terminales C durante la ELAF, hemos encontrado cambios asociados con la aparición de síntomas, como por ejemplo el incremento de la expresión del factor neurotrófico Neuregulina-1, localizado por primera vez en la cisterna subsináptica de los terminales C. La Neuregulina-1 en esas estructuras de retículo endoplasmático fue observada dentro de vesículas extracelulares (VEs), sugiriendo que el análisis de la Neuregulina-1 dentro de VEs en la ELA resulta especialmente prometedor como biomarcador potencial para esta enfermedad. Así, nosotros hemos desarrollado también un nuevo método para purificar VEs, dado que este es un paso esencial previo al estudio de las proteínas asociadas con estas estructuras. Nuestro método aplicado a la purificación de VEs de tejidos complejos fue capaz de facilitar la identificación de la Neuregulina en VEs provenientes de tejidos clínicos y fluidos biológicos. En relación a las implicaciones de la mitocondria en la ELA, hemos encontrado que la mutación SOD1-G93A estabiliza la proteína PINK1 en las mitocondrias activando el factor nuclear NFκB en neuronas. La interacción secuencial entre la SOD1 mutante y el NFκB crea una clara disfunción sobre la capacidad proteolítica del proteosoma, la cual a su vez promueve co-agregación de la SOD1 mutante y PINK1 en estas células. Estos resultados suman un sustancial conocimiento mecanístico sobre los roles de la mitocondria en eventos degenerativos clásicos de la ELA, como es la agregación de proteínas disfuncionales en motoneuronas. Siguiendo nuestro estudio de la afectación mitocondrial en la ELA, hemos creado y caracterizado un nuevo modelo de Drosophila que expresa la mutación humana SOD1-G93A en fibras musculares torácicas bajo el promotor 24B. Este modelo de Drosophila transgénica recapitula con éxito en fenotipo mitocondrial característico de la ELA presentando importantes ventajas para la elección de nuevos compuestos terapéuticos. En definitiva, los resultados generados en esta tesis proporcionan evidencia experimental, extensa comprensión molecular y insinúan nuevos horizontes terapéuticos acerca de los mecanismos moleculares y eventos neurodegenerativos asociados con la disfunción sináptica y la disfunción mitocondrial en la ELAF.Amyotrophic Lateral Sclerosis (ALS) is an orphan age-associated neurodegenerative disease. All motoneurones in ALS are affected by degenerative flow from the primary motor cortex to the neuromuscular junction. In 1993, mutations of the gene SOD1 opened new research avenues allowing for the generation of familial ALS experimental models in rodents. Since then, the FALS mutation SOD1-G93A has been extensively studied worldwide in ALS to date. Transgenic models for this SOD1 mutation have revealed essential mechanisms of neurodegeneration including excitotoxicity, proteinopathy and axosynaptic degeneration among others. In this dissertation, we explored the molecular changes that occur in C-terminals, a very specialised synapse type from α-motoneurones of SOD1-G93A rodents. Also, we focused on the pathological relationship between the FALS mutant SOD1-G93A and mitochondria in motoneurones. With regard to C-terminals in FALS motoneurones, we found changes that were symptomatically associated with the up-regulated expression of the neurotrophic factor Neuregulin-1 located for the first time in the subsurface system of C-boutons juxtaposed to α-motoneurones. Furthermore, Neuregulin-1 in these endoplasmic reticulum structures was observed inside extracellular vesicles, suggesting that analysis of Neuregulin-1 from extracellular vesicles in ALS holds promise as a potential reliable biomarker for that neurodegenerative disease. We therefore have developed a new method for isolation of extracellular vesicles, as this remains as an essential step for the study of molecules associated with these structures. Our method applied to purify extracellular vesicles from complex biological tissues was able to facilitate the identification of Neuregulin-1 in extracellular vessicles from clinical tissues and biological fluids. Regarding implications of mitochondria in ALS, we have found that the FALS mutant hSOD1-G93A stabilises PINK1 in mitochondria and subsequently activates NFκB in neuronal cells. Sequential interaction between hSOD1 and NFκB impairs the proteosome proteolitic function promoting co-aggregation of SOD1 and PINK1 in these cells. These results add substantial mechanistic insight on the roles of mitochondria in classical ALS-associated neurodegenerative events, including aggregation of dysfuntional proteins in motoneurones. Following our study of mitochondria affectation in ALS, we have created and characterised a novel Drosophila model that expresses human SOD1-G93A in thoracic muscles under the genetic muscular promoter 24B. Flies expressing human SOD1-G93A in thoracic muscles successfully recapitulate FALS mitochondrial phenotype with several advantages in front of the current available rodent models for this FALS mutation. Taken together, the results generated in this thesis provide experimental evidence, further molecular comprehension and promise novel therapeutic approaches to the molecular mechanisms and neurodegenerative events associated with synaptic frailty and mitochondrial disfunction in FALS

Evaluation of two methods for measuring saturated hydraulic conductivity of soils under two vegetation covers

Postprint (published version

Drosophila expressing human SOD1 successfully recapitulates mitochondrial phenotypic features of familial amyotrophic lateral sclerosis

Mitochondrial pathology is a seminal pathogenic hallmark of familial amyotrophic lateral sclerosis (FALS) which is extensively manifested by human patients and mutant SOD1G93A mammalian models. Rodents expressing human FALS-associated mutations successfully mimic several human disease features; although they are not as amenable to genetic and therapeutic compound screenings as non-mammalian models. In this study, we report a newly generated and characterized Drosophila model that expresses human SOD1G93A in muscle fibers. Presence of SOD1G93A in thoracic muscles causes mitochondrial pathology and impairs normal motor behavior in these flies. Use of this new FALS-24B-SOD1G93A fly model holds promise for better understanding of the mitochondrial affectation process in FALS and for the discovery of novel therapeutic compounds able to reverse mitochondrial dysfunction in this fatal disease

Leveraging bi-directional EV charging for flexibility services in the distribution grid - the case of fever project

© 2022 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting /republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistributionDistribution System Operators face a challenging environment largely affected by the ever-growing integration of Distributed Energy Resources. Especially, Electric Vehicles have a rapidly growing presence in the distribution grids, being both a challenge, but also an enabler for active network management. This work analyses the operation of charging infrastructures in coordination with the DSO in the context of the FEVER project. The objective of the project is to exploit control of power flow through DC/AC converters towards demand management and voltage compensation. The paper describes the different modules required to coordinate this operation in a flexibility market context. DSO support tools have been developed to forecast possible critical events and prepare a mitigation plan leveraging flexibility. Response to this flexibility demand is covered by Vehicle-to-Grid charging stations, equipped with DC converters, capable of implementing flexibility strategies.Peer ReviewedObjectius de Desenvolupament Sostenible::13 - Acció per al ClimaObjectius de Desenvolupament Sostenible::7 - Energia Assequible i No ContaminantPostprint (published version

Developing novel technologies and services for intelligent low voltage electricity grids: cost–benefit analysis and policy implications

The paper presents a set of prototype smart grid technologies and services and validates the economic viability of the proposed solution using cost–benefit analysis (CBA). The study considered the EU-funded project called RESOLVD and implemented the technologies and services in a real-life pilot. the technologies and services on the EU-funded H2020. The paper focuses on the analysis of technological solutions which enhance the operational efficiency and the hosting capacity of low-voltage electricity distribution grids. The solutions provided better integration of a hybrid battery storage system, with the grid interfacing power electronics, smart gateways for the interconnection of assets at the grid edge, and sensors enhancing infrastructure observability and control. The result from the CBA indicates the economic viability of the project, high scalability, and replicability. The economic benefits were realized with the breakeven value of eight secondary substations (SS) and 16 feeders. The scenario test on the DSO’s willingness to pay for the software as a service (SaaS) revealed that the payback period can further be reduced by almost half with a higher internal rate of return (IRR) and net present value (NPV). Both the CBA and scenario tests showed RESOLVD solution can become more economically viable when deployed in largescale. Moreover, the CBA results provide evidence to the energy policy by allowing DSOs to consider both CAPEX and OPEX for better investment decisions. Further, the paper proposes an alternative business approach that shifts from grid reinforcement to service provision. The paper also discusses the research implications on energy policy and business.Peer ReviewedObjectius de Desenvolupament Sostenible::9 - Indústria, Innovació i InfraestructuraObjectius de Desenvolupament Sostenible::11 - Ciutats i Comunitats SosteniblesPostprint (published version

Told through the wine: a liquid chromatography-mass spectrometry interplatform comparison reveals the influence of the global approach on the final annotated metabolites in non-targeted metabolomics

This work focuses on the influence of the selected LC-HRMS platform on the final annotated compounds in non-targeted metabolomics. Two platforms that differed in columns, mobile phases, gradients, chromatographs, mass spectrometers (Orbitrap [Platform#1] and Q-TOF [Platform#2]), data processing and marker selection protocols were compared. A total of 42 wines samples from three different protected denomination of origin (PDO) were analyzed. At the feature level, good (O)PLS-DA models were obtained for both platforms (Q2[Platform#1]=0.89, 0.83 and 0.72; Q2[Platform#2]=0.86, 0.86 and 0.77 for Penedes, Ribera del Duero and Rioja wines respectively) with 100% correctly classified samples in all cases. At the annotated metabolite level, platforms proposed 9 and 8 annotated metabolites respectively which were identified by matching standards or the MS/MS spectra of the compound. At this stage, none of the suggested metabolites was coincident between platforms. When screened on the raw data, 6 and 5 of these compounds were detected on the other platform with a similar trend. Some of the detected metabolites showed complimentary information when integrated on biological pathways. Through the use of some examples at the annotated metabolite level, possible explanations of this initial divergence on the results are presented. This work shows the complications that may arise on the comparison of non-targeted metabolomics platforms even when metabolite focused approaches are used in the identificatio

Arquitectura de una red inteligente rural

El trabajo presentado se enmarca en e l proyecto europeo del programa FP - 7 Smart Rural Grid que tiene como objetivo desarrollar la red rural inteligente y explorar las mejores maneras de hacer la transición de las actuales redes de distribución en zonas rurales a las nuevas redes inteligentes utilizando las nuevas tecnologías y conceptos de negocio a sociados. El proyecto reconsidera la arquitectura de la red de distribución rural actual, acomodando telecomunicaciones, tecnologías de control, almacenamiento y otros sistemas y dispositivos para renovar las estructuras existentes y - probar el nuevo conce pto desarrollado , basado en incrementar entre otros, la resiliencia de la red dando lugar a una nueva estructura de red p seudomallada.Postprint (published version

Combining biocatalysts to achieve new phase change materials. Application to non-edible animal fat

"Formerly known as Journal of Molecular Catalysis A: Chemical"The thermal properties of various alkyl threo-9, 10-dihydroxystearates (DHSEs) prepared from non-edible fat were studied. Non-edible animal fat was hydrolyzed in a 93% yield with R. oryzae resting cells. Crude unsaturated fatty acids were recovered from the matter liquor resulting from a crystallization performed to achieve the saturated fatty acids. These unsaturated free fatty acids were epoxidized with 30% H2O2 using immobilized Candida antarctica Lipase-B (CAL-B) as biocatalyst. The epoxy ring was cleaved with hot water in the presence of tert-butanol (t-BuOH). Pure threo-9, 10-dihydroxystearic acid (DHSA) from animal fat was recovered by crystallization (51% yield). Subsequently, DHSA was esterified in alpha-limonene using biocatalysts yielding twelve DHSEs (58-90% yield). Differential scanning calorimetry (DSC) analysis of these esters revealed potential latent heats ranging from 136.83 kJ kg−1 to 234.22 kJ kg−1 and melting temperatures from 52.45 ◦C to 76.88 ◦C. Finally, the compounds with enthalpies above 200 kJ kg−1 were subjected to 100 and 1000 thermal cycles. These experiments showed that these products present good thermal reliability.GREA and DBA are certified agents TECNIO in the category of technology developers from the Government of Catalonia. We thanks to Subproductos Cárnicos Echevarria y Asociados S.L (Cervera, Spain) for supplying the non-edible fat. Moreover, the research leading to these results has received funding from the European Commission Seventh Framework Programme (FP/2007-2013) under grant agreement no PIRSES-GA-2013-610692 (INNOSTORAGE) and from the European Union’s Horizon 2020 research and innovation program under grant agreement no 657466 (INPATH-TES). The authors would like to thank the Catalan Government for the quality accreditation given to their research groups GREA (2014 SGR 123) and Agricultural Biotechnology Research Group (2014 SGR 1296). This work has been partially funded by the Spanish government (CTQ2015-70982-C3-1-R (MINECO/FEDER) and ENE2015-64117-C5-1-R (MINECO/FEDER). Aran Solé would like to thank Ministerio de Economía y Competitividad de España for Grant Juan de la Cierva, FJCI-2015-25741

The effect of external stimulation on functional networks in the aging healthy human brain

Understanding the brain changes occurring during aging can provide new insights for developing treatments that alleviate or reverse cognitive decline. Neurostimulation techniques have emerged as potential treatments for brain disorders and to improve cognitive functions. Nevertheless, given the ethical restrictions of neurostimulation approaches, in silico perturbation protocols based on causal whole-brain models are fundamental to gaining a mechanistic understanding of brain dynamics. Furthermore, this strategy could serve to identify neurophysiological biomarkers differentiating between age groups through an exhaustive exploration of the global effect of all possible local perturbations. Here, we used a resting-state fMRI dataset divided into middle-aged (N =310, <65 years) and older adults (N =310, ≥65) to characterize brain states in each group as a probabilistic metastable substate (PMS) space. We showed that the older group exhibited a reduced capability to access a metastable substate that overlaps with the rich club. Then, we fitted the PMS to a whole-brain model and applied in silico stimulations in each node to force transitions from the brain states of the older- to the middle-aged group. We found that the precuneus was the best stimulation target. Overall, these findings could have important implications for designing neurostimulation interventions for reversing the effects of aging on whole-brain dynamics