Ciencias Fisiologicas

Young Researchers Symposia SCHCF + ALACF 2020

YRS1 – Aquaporins in physiological and pathological conditions

Coordinator: Raúl A. Marinelli (Instituto de Fisiología Experimental (IFISE-CONICET), Universidad Nacional de Rosario, Rosario, Argentina)

The aquaporins (AQPs) are a family of intrinsic membrane channel proteins that facilitate the osmotically-driven movement of water molecules. Some AQPs also display permeability to certain small uncharged molecules. AQPs assemble into tetrameric functional units, essential to life, being expressed in all kingdoms. In humans, there are 13 AQPs, at least one of which is found in every organ system. The structural biology of the AQP family is well-established and many functions for AQPs have been reported in health and disease. The targeted modulation of AQPs therefore presents an opportunity to develop novel treatments for diverse conditions or reliable diagnostic and prognostic biomarkers. This symposium aims to highlight the relevance of AQPs in the context of some pathological conditions such as neuromyelitis optica, cholestasis and preeclampsia.

Speakers

Natalia Szpilbarg (Assistant Researcher, CONICET, Laboratorio de Biología de la Reproducción, IFIBIO UBA-CONICET, Universidad de Buenos Aires, Argentina)Possible role of AQP3 in the etiology of preeclampsia

Vanina Netti (Assistant Researcher, CONICET. Laboratorio de Biomembranas, IFIBIO UBA-CONICET, Universidad de Buenos Aires, Argentina)Role of aquaporin-4 as an osmosensor in retinal müller cells: implications in the physiopathology of neuromyelitis optica spectrum disorder

Julieta Marrone (Assistant Researcher, CONICET. Instituto de Fisiología Experimental, IFISE-CONICET, Universidad Nacional de Rosario, Argentina)Hepatic gene transfer of Aquaporins for cholestasis

YRS2 – Biology of exercise in metabolic disorders

Coordinator: Sergio Martínez Huenchullán (Universidad Austral de Chile, Chile)

Obesity is a global health problem, where its high prevalence worldwide, and particularly in Latin America, is associated with the development of metabolic complications ranging from insulin resistance and type 2 diabetes, to cardiovascular disease, and non-alcoholic fatty liver disease. Therefore, strategies that aim to counter these obesity-derived complications have been in increasing develop in the last decades. From those, physical exercise is one of the most effective lifestyle modifications used to manage obesity and its comorbidities. However, even when its health benefits are well-known, the physiological mechanisms behind these processes are far from being fully understood. Organ-cross talk, redox signaling, and insulin-signaling are some of the processes being currently investigated. The motivation behind the scientific exploration of this knowledge gap resides in develop advances towards the individualization of exercise modalities as therapy for metabolic disorders. This symposium aims to highlight some of the recent advances in the understanding of the physiological mechanisms and effects of exercise in the context of metabolic dysfunction, particularly focused on obesity and insulin resistance, along with some of the future challenges in the field.

Speakers

Carlos Henríquez-Olguín (Postdoc, University of Copenhagen, Denmark)Intracellular hydrogen peroxide as signal for molecular responses to exercise.

Jonas Roland Knudsen (Postdoc, École Polytechnique Fédérale de Lausanne, Switzerland)Novel insights into GLUT4 in insulin-sensitized and –resistant skeletal muscle

Sergio Martínez-Huenchullán (Lecturer-Researcher, Austral University of Chile, Chile) Influence of exercise intensity on metabolic adaptations in an obesity context.

YRS3 – Protein and membrane interaction, always a good interaction? Osmoionic imbalances and signalling mechanisms in pathological contexts

Coordinator: Pablo J. Schwarzbaum (Principal Researcher CONICET – Instituto de Química y Fisicoquímica Biológicas “PROF. ALEJANDRO C. PALADINI”, Argentina)

Exposure to toxins from different organisms can trigger a variety of responses in different cell types. In human erythrocytes, both exposure to the peptide Mastoparan-7 and exposure to the toxin alpha-hemolysin (HlyA, secreted by uropathogenic strains of E. coli (UPEC), activate signalling mechanisms mediated by extracellular ATP and induce an osmotic imbalance in these cells. On the other hand, it has been shown that HlyA in an important virulence factor in the pathogenesis of urinary tract infections in pregnant women, where UPEC strains are responsible of the 80% of the infections. Exposure to HlyA of human chorioamniotic membranes induce the remodelling of the extracellular matrix, leading to a premature birth or abortion. It has been suggested that the damage induce by toxin-membrane interaction might be mediated by the alteration of water homeostasis, among other mechanisms, due to the interaction of the toxins with one or more aquaporin present in the cell membrane. This interaction would trigger lytic mechanisms in different tissues during the course of a bacterial infection or a toxin-induce cellular injury. Since the discovery of aquaporin 1 (AQP1, the main water transport channel in human erythrocytes) and each member of the AQP family, it has been studying the role of these transmembrane channels in the sensing and the regulation of the water homeostasis in all domains of life. These channels transport water and small molecules. Beyond the specificity of transport, their functional diversification would be determined both by the expression patterns and by the set of gating mechanisms and the interaction with proteins that regulate their location in the membrane, resulting in an alteration in water homeostasis.

Speakers

Victoria A. Vitali (Postdoc CONICET – Instituto de Química y Fisicoquímica Biológicas “Prof. Alejandro C. Paladini”, Argentina) Functional diversification of aquaporins: the case of the PIP subfamily

María Florencia Leal Denis (Assistant Researcher CONICET – Instituto de Química y Fisicoquímica Biológicas ” Prof. Alejandro C. Paladini”, Argentina) Effect of mastoran-7 and alpha-hemolysin on ATP release and cell volume in human erythrocytes. The role of aquaporin 1

Melisa Pucci Molineris (Postdoc CONICET – Instituto de Investigaciones Bioquímicas de La Plata “Prof. Dr. Rodolfo R. Brenner”, Argentina) Role of alpha-hemolysin in the extracellular matrix remodeling of human chorioamniotic membranes

YRS4 – Sarco-endoplasmic reticulum-mitochondrial coupling in physiology and pathophysiology

Coordinator: Julieta Palomeque (National University of La Plata & Independent Researcher, CONICET, Argentina)

The physical links between Sarco-endoplasmic reticulum (SR/ER) and mitochondria were firstproposed over 40 years ago based on transmission electron microscopy of liver mitochondria.SR/ER and mitochondria join together at contact sites to form specific domains, termedmitochondria associated membranes (MAMs), with a characteristic set of proteins and distinctbiochemical properties. Interorganellar contacts are increasingly recognized as central to the control of cellular behaviour. A significant body of evidence shows clearly that the association between SR/ER and mitochondria play important roles in several biological processes, e.g. ion and lipid transfer, inflammasome formation, unfolded protein response, autophagy, signalling and mitochondrial fission have been established. Furthermore, the changes in MAMs have been implicated in different diseases, e.g. Alzheimer’s disease, cancer, metabolic disease, and cardiac ischemia reperfusion. The objective of this symposium is to develop and highlight recent findings that reveal the crucial role of SR/ER-mitochondrial coupling in physiology and pathophysiology. We convoked 3 early careers from different countries and that have embraced this topic with enthusiasm. Although data available on the proteins that constitute MAMs are constantly increasing, there are still many uncertainties concerning the exact composition of these contact points and how it changes in response to various stimuli and cellular stress. The symposium is therefore more than timely, and the speakers proposed were selected to emphasize that SR/ER-mitochondria coupling has become a hot topic in physiology and pathophysiology.

Speakers

Ferderico Marilén (Cardiovascular Research Center, National University of La Plata (UNLP) SR-Mitochondria communication promotes mitochondrial damage and apoptosis in prediabetic hearts

Sergio De La Fuente Pérez (Thomas Jefferson University, USA)Strategic positioning of the mitochondrial Ca2+ transporters at the SRmitochondria interface in the cardiac tissue

Roberto Bravo Sagua (Unidad de Nutrición Pública INTA – Universidad de Chile, Chile) Caveolin-1 and PKA regulate ER-mitochondria communication during the early response to ER stress

YRS5 – Inflammation in the cardiovascular system: a multifaceted pathway

Coordinator: Verónica De Giusti (Universidad Nacional de La Plata & Adjunct Researcher, National Council for Scientific and Technical Research (CONICET), Argentina)

Although the role of inflammation in the onset of cardiovascular disease is not yet fully understood, inflammation is common in heart and vascular disease. It’s important to know what inflammation is and how it can affect the cardiovascular system. This symposium covers traditional and non-traditional risk factors like hypertension, obesity, and air pollution exposure that have high prevalence in the modern society and are closely related to chronic inflammatory states that can injure the healthy heart by modulating specific intracellular signalling pathways. Although all molecular mechanisms have not been clearly defined, the exposure to pro inflammatory cytokines, reactive oxygen species and free fatty acids intermediaries have been suggested as key elements in the cardiovascular homeostasis. The study of the inflammatory role in these risk factors, as well as possible modulators, could gradually lead to development of more effective therapeutic strategies to prevent cardiovascular events.

Speakers

Timoteo Marchini (Universidad de Buenos Aires, Argentina, Assistant Researcher IBIMOL-CONICET, Argentina & Researcher at the Friburgo University Hospital, Germany) Inflammatory and metabolic pathways modulated by environmental factors in cardiovascular disease onset and progression

Carolina Caniffi  (Universidad de Buenos Aires, Argentina & Researcher IQUIMEFA-UBA-CONICET, Argentina) Anti-inflammatory and anti-oxidant protection through C-type natriuretic peptide in normotension and hypertension

Rodrigo García (Doctoral Fellow, IMBECU-CONICET, Argentina) Protective effects of hydroxychloroquine in cardiovascular remodelling associated with metabolic syndrome