Angiotensin-(1-7) through Mas receptor up-regulates neuronal norepinephrine transporter via Akt and Erk1/2-dependent pathways

As angiotensin (Ang) (1-7) decreases norepinephrine (NE) content in the synaptic cleft, we investigated the effect of Ang-(1-7) on NE neuronal uptake in spontaneously hypertensive rats. [ 3H]-NE neuronal uptake was measured in isolated hypothalami. NE transporter (NET) expression was evaluated in hypothalamic neuronal cultures by western-blot. Ang-(1-7) lacked an acute effect on neuronal NE uptake. Conversely, Ang-(1-7) caused an increase in NET expression after 3 h incubation (40 ± 7%), which was blocked by the Mas receptor antagonist, a PI3-kinase inhibitor or a MEK1/2 inhibitor suggesting the involvement of Mas receptor and the PI3-kinase/Akt and MEK1/2-ERK1/2 pathways in the Ang-(1-7)-stimulated NET expression. Ang-(1-7) through Mas receptors stimulated Akt and ERK1/2 activities in spontaneously hypertensive rat neurons. Cycloheximide attenuated Ang-(1-7) stimulation of NET expression suggesting that Ang-(1-7) stimulates NET synthesis. In fact, Ang-(1-7) increased NET mRNA levels. Thus, we evaluated the long-term effect of Ang-(1-7) on neuronal NE uptake after 3 h incubation. Under this condition, Ang-(1-7) increased neuronal NE uptake by 60 ± 14% which was blocked by cycloheximide and the Mas receptor antagonist. Neuronal NE uptake and NET expression were decreased after 3 h incubation with an anti-Ang-(1-7) antibody. Ang-(1-7) induces a chronic stimulatory effect on NET expression. In this way, Ang-(1-7) may regulate a pre-synaptic mechanism in maintaining appropriate synaptic NE levels during hypertensive conditions.Fil: Lopez Verrilli, María Alejandra. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Química y Físico-Química Biológicas "Prof. Alejandro C. Paladini". Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Instituto de Química y Físico-Química Biológicas; ArgentinaFil: Rodríguez Fermepin, Martin. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Longo, Nadia Andrea. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Química y Físico-Química Biológicas "Prof. Alejandro C. Paladini". Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Instituto de Química y Físico-Química Biológicas; ArgentinaFil: Landa, Maria Silvina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones Médicas. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones Médicas; ArgentinaFil: Cerrato, Bruno Diego. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Química y Físico-Química Biológicas "Prof. Alejandro C. Paladini". Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Instituto de Química y Físico-Química Biológicas; ArgentinaFil: Garcia, Silvia Ines. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones Médicas; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones Médicas. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones Médicas; ArgentinaFil: Fernandez, Belisario Enrique. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Gironacci, Mariela Mercedes. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Química y Físico-Química Biológicas "Prof. Alejandro C. Paladini". Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Instituto de Química y Físico-Química Biológicas; Argentin

Extracellular vesicles and intercellular communication within the nervous system

Extracellular vesicles (EVs, including exosomes) are implicated in many aspects of nervous system development and function, including regulation of synaptic communication, synaptic strength, and nerve regeneration. They mediate the transfer of packets of information in the form of nonsecreted proteins and DNA/RNA protected within a membrane compartment. EVs are essential for the packaging and transport of many cell-fate proteins during development as well as many neurotoxic misfolded proteins during pathogenesis. This form of communication provides another dimension of cellular crosstalk, with the ability to assemble a “kit” of directional instructions made up of different molecular entities and address it to specific recipient cells. This multidimensional form of communication has special significance in the nervous system. How EVs help to orchestrate the wiring of the brain while allowing for plasticity associated with learning and memory and contribute to regeneration and degeneration are all under investigation. Because they carry specific disease-related RNAs and proteins, practical applications of EVs include potential uses as biomarkers and therapeutics. This Review describes our current understanding of EVs and serves as a springboard for future advances, which may reveal new important mechanisms by which EVs in coordinate brain and body function and dysfunction

MSCs-Derived Exosomes: Cell-Secreted Nanovesicles with Regenerative Potential

Exosomes are membrane-enclosed nanovesicles (30-150 nm) that shuttle active cargoes between different cells. These tiny extracellular vesicles have been recently isolated from mesenchymal stem cells (MSCs) conditioned medium, a population of multipotent cells identified in several adult tissues. MSCs paracrine activity has been already shown to be the key mediator of their elicited regenerative effects. On the other hand, the individual contribution of MSCs-derived exosomes for these effects is only now being unraveled. The administration of MSCs-derived exosomes has been demonstrated to restore tissue function in multiple diseases/injury models and to induce beneficial in vitro effects, mainly mediated by exosomal-enclosed miRNAs. Additionally, the source and the culture conditions of MSCs have been shown to influence the regenerative responses induced by exosomes. Therefore, these studies reveal that MSCs-derived exosomes hold a great potential for cell-free therapies that are safer and easier to manipulate than cell-based products. Nevertheless, this is an emerging research field and hence, further studies are required to understand the full dimension of this complex intercellular communication system and how it can be optimized to take full advantage of its therapeutic effects. In this mini-review, we summarize the most significant new advances in the regenerative properties of MSCs-derived exosomes and discuss the molecular mechanisms underlying these effects.Prémios Santa Casa Neurociências - Prize Melo e Castro for Spinal Cord Injury Research; Portuguese Foundation for Science and Technology (Doctoral fellowship - PDE/BDE/113598/2015 to AM. IF Development Grant to AS). This article is a result of the project (NORTE-01-0145-FEDER-000013), supported by Norte Portugal Regional Operational Programme (NORTE 2020), under the PORTUGAL 2020 Partnership Agreement, through the European Regional Development Fund (ERDF) Cofinanciado pelo Programa Operacional Regional do Norte (ON.2 SR&TD Integrated Program – NORTE-07-0124-FEDER-000021), ao abrigo do Quadro de Referência Estratégico Nacional (QREN), através do Fundo Europeu de Desenvolvimento Regional (FEDER); Projeto Estratégico – LA 26 – 2011-2012 and Projeto Estratégico – LA 26 – 2013-2014 cofinanciado por fundos nacionais, através da Fundação para a Ciência e a Tecnologia (PEst-C/SAU/LA0026/2011; PEst-C/SAU/LA0026/2013), e pelo Fundo Europeu de Desenvolvimento Regional (FEDER), através do COMPETE (FCOMP-01-0124-FEDER-022724; FCOMP-01-0124-FEDER-037298)info:eu-repo/semantics/publishedVersio

Bone marrow mesenchymal stem cells' secretome exerts neuroprotective effects in a Parkinson's disease rat model

Parkinson's disease (PD) is characterized by a selective loss of dopamine (DA) neurons in the human midbrain causing motor dysfunctions. The exact mechanism behind dopaminergic cell death is still not completely understood and, so far, no cure or neuroprotective treatment for PD is available. Recent studies have brought attention to the variety of bioactive molecules produced by mesenchymal stem cells (MSCs), generally referred to as the secretome. Herein, we evaluated whether human MSCs-bone marrow derived (hBMSCs) secretome would be beneficial in a PD pre-clinical model, when compared directly with cell transplantation of hBMSCs alone. We used a 6-hydroxydpomanie (6-OHDA) rat PD model, and motor behavior was evaluated at different time points after treatments (1, 4, and 7 weeks). The impact of the treatments in the recovery of DA neurons was estimated by determining TH-positive neuronal densities in the substantia nigra and fibers in the striatum, respectively, at the end of the behavioral characterization. Furthermore, we determined the effect of the hBMSCs secretome on the neuronal survival of human neural progenitors in vitro, and characterized the secretome through proteomic-based approaches. This work demonstrates that the injection of hBMSCs secretome led to the rescue of DA neurons, when compared to transplantation of hBMSCs themselves, which can explain the recovery of secretome-injected animals' behavioral performance in the staircase test. Moreover, we observed that hBMSCs secretome induces higher levels of in vitro neuronal differentiation. Finally, the proteomic analysis revealed that hBMSCs secrete important exosome-related molecules, such as those related with the ubiquitin-proteasome and histone systems. Overall, this work provided important insights on the potential use of hBMSCs secretome as a therapeutic tool for PD, and further confirms the importance of the secreted molecules rather than the transplantation of hBMSCs for the observed positive effects. These could be likely through normalization of defective processes in PD, namely proteostasis or altered gene transcription, which lately can lead to neuroprotective effects.Portuguese Foundation for Science and Technology: IF Development Grant (IF/00111/2013) to AS, Post-Doctoral Fellowship to FT (SFRH/BPD/118408/2016) and Doctoral Fellowship to BM-P (SFRH/BD/120124/2016); Canada Research Chair in Biomedical Engineering (LAB). This work was funded by FEDER, through the Competitiveness Internationalization Operational Programme (POCI), and by National funds, through the Foundation for Science and Technology (FCT), under the scope of the projects: POCI-01-0145-FEDER-029751; POCI-01-0145-FEDER-007038; POCI-01-0145-FEDER-032619; POCI-01-0145-FEDER-016428 (ref.: SAICTPAC/0010/2015), POCI-01-0145-FEDER-016795 (ref.: PTDC/NEU-SCC/7051/2014), POCI-01-0145-FEDER-029311 (ref.: PTDC/BTM-TEC/29311/2017), POCI-01-0145-FEDER-30943 (ref.: PTDC/MEC-PSQ/30943/2017) and PTDC/MED-NEU/27946/2017; UID/NEU/04539/2013 and POCI-01-0145-FEDER-007440. This article has also been developed under the scope of the project NORTE-01-0145-FEDER-000023, supported by the Northern Portugal Regional Operational Programme (NORTE 2020), under the Portugal 2020 Partnership Agreement, through the European Regional Development Fund (FEDER). Co-funded by the Programa Operacional Factores de Competitividade (QREN) and by The National Mass Spectrometry Network under the contract POCI-01-0145-FEDER-402-022125 (ref.: ROTEIRO/0028/2013

Nanotechnology in peripheral nerve repair and reconstruction

The recent progress in biomaterials science and development of tubular conduits (TCs) still fails in solving the current challenges in the treatment of peripheral nerve injuries (PNIs), in particular when disease-related and long-gap defects need to be addressed. Nanotechnology-based therapies that seemed unreachable in the past are now being considered for the repair and reconstruction of PNIs, having the power to deliver bioactive molecules in a controlled manner, to tune cellular behavior, and ultimately guide tissue regeneration in an effective manner. It also offers opportunities in the imaging field, with a degree of precision never achieved before, which is useful for diagnosis, surgery and in the patientâ s follow-up. Nanotechnology approaches applied in PNI regeneration and theranostics, emphasizing the ones that are moving from the lab bench to the clinics, are herein overviewed.The authors acknowledge the Portuguese Foundation for Science and Technology (FCT) for the financial support provided to Joaquim M. Oliveira (IF/01285/2015) and Joana Silva-Correia (IF/00115/2015) under the program “Investigador FCT”.info:eu-repo/semantics/publishedVersio

La lectura y escritura relacional El aula como intersticio

En estas páginas nos proponemos reflexionar en torno a la lectura y la escritura como posibles procesos de producción, partiendo de la interrelación de ambos términos y prácticas. Lejos de cerrar conceptos e ideas, este texto intenta operar como un disparador de preguntas que nos permitan problematizar la escritura académica y abrir discusiones sobre qué se escribe y cómo se escribe en un taller de arte, tomando como objeto de análisis los textos producidos por los alumnos de Teoría del Color comisión C.The propose of the following pages is to think over reading and writing as possible production processes, based on the interplay of both terms and practices. Far from closing concepts and ideas, this text operates as a trigger that allow us to problematize academic writing and open discussions about what is written and how is written in an art workshop, analyzing texts produced by the students of Color Theory class C.Lopez Verrilli, Maria Clara. Universidad Nacional de Rosario; Argentina

Exosomes: mediators of communication in eukaryotes

In addition to the established mechanisms of intercellular signaling, a new way of communication has gained much attention in the last decade: communication mediated by exosomes. Exosomes are nanovesicles (with a diameter of 40-120 nm) secreted into the extracellular space by the multivesicular endosome after its outer membrane fuses with the plasma membrane. Once released, exosomes modulate the response of the recipient cells that recognize them. This indicates that exosomes operate in a specific manner and participate in the regulation of the target cell. Remarkably, exosomes occur from unicellular organisms to mammals, suggesting an evolutionarily conserved mechanism of communication. In this review we describe the cascade of exosome formation, intracellular traffic, secretion, and internalization by recipient cells, and review their most relevant effects. We also highlight important steps that are still poorly understood

Lo real cotidiano en las escrituras contemporáneas

El proyecto se inscribe en el marco de los estudios de la discursividad social y su objeto son las prácticas escriturarias que se producen en muy diversas esferas, focalizando en un recurrente objeto de tematización: la realidad cotidiana. Desde lo metodológico, es una investigación cualitativa y exploratoria en la que las tareas de investigación se moverán en una doble dirección. Por un lado indagación teórica acerca de un conjunto heterogéneo y heteróclito de escrituras: algunas de ellas pertenecientes a los campos consolidados como esferas de la escritura y otras que están por fuera, en los bordes, inclasificables ocurrencias siempre novedosas y cambiantes como para ser catalogadas. En cuanto a la contemporaneidad de las escrituras, partimos del presupuesto por el cual el anacronismo atraviesa todas las contemporaneidades, como un modo temporal en el que se expresan la hibridación, la superposición y el borramiento de fronteras. Proponemos la noción de lo real cotidiano como un modo de abordar diferentes manifestaciones de la producción escrituraria contemporánea, por lo que la noción misma se constituye como una hipótesis de lectura. Lo real cotidiano se plantea como un universo a delimitar en el proceso investigativo, un punto de partida, una dimensión de lectura de un fenómeno de época en el que el tiempo presente y la propia vida se han convertido en objeto de tematización mediante un registro/relato del acontecer diario. Proponemos un régimen epistémico abierto, al modo benjaminiano, a partir del cual el anacronismo y lo real cotidiano permitirán complejizar los modelos de temporalidad y veracidad de las escrituras analizadas. Este proyecto se propone estudiar las escrituras (y no sólo los textos) en cuanto a estrategias enunciativas, tematización, modos de leer, regímenes de sentido, regímenes de realidad, estatuto de autor, fronteras genéricas. Por otro lado, se propone un desarrollo experimental a partir de la producción de textos, en diferentes lenguajes y formatos, como un proceso de permanente retroalimentación entre la lectura sistemática, el análisis y la producción exploratoria. La investigación implicará tanto producción conceptual como desarrollo experimental a partir de cinco aspectos formales de lo real cotidiano en las escrituras contemporáneas: la narrativa, lo autobiográfico, el fragmentarismo, lo ensayístico y la intertextualidad. Aunque prevemos una permanente reconstitución de un corpus de trabajo a partir del análisis y la experimentación, se establecen algunas escrituras iniciales en cada uno de los ejes propuestos. El proyecto prevé la incorporación paulatina de recursos humanos de distinto nivel de formación en función de la práctica docente del equipo de investigación y en relación al desarrollo experimental propuesto que contempla la producción y experimentación con distintas materialidades significantes, así como sus consecuentes acciones de publicación y divulgación.Fil: Calamari, Andrea Mariel. Universidad Nacional de Rosario. Facultad de Ciencia Política y Relaciones Internacionales; Argentina