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Las acuaporinas son proteínas de las membranas celulares que forman poros y por las cuales pasan varios tipos de moléculas, pero principalmente estas proteínas se encargan del transporte del agua. La acuaporinas se encuentran en las células de los diferentes tejidos del cuerpo y son parte importante de los mecanismos de homeostasis, del manejo de los líquidos corporales y el volumen celular. Participan en funciones tan diversas como la angiogénesis o patologías como el edema, la epilepsia o las enfermedades de Parkinson y Alzheimer. En esta revisión se mencionan algunas de las evidencias que se han acumulado en los últimos años y que relacionan a las acuaporinas con los procesos fisiológicos o patológicos en el sistema cardiovascular y el sistema nervioso. Aquaporins are membrane proteins that form channels through which various types of molecules pass, but mainly, these proteins are responsible for the transport of water. Aquaporins are found in almost all cells of different tissues of the body and are an important part of the homeostatic mechanisms of body fluid management and cell volume. They participate in functions as diverse as angiogenesis or learning, and their high or low expression has been related to pathologies such as edema, epilepsy or Parkinson's and Alzheimer’s diseases. This review will mention some of the evidences that have accumulated and that relate aquaporins with physiological or pathological processes in the cardiovascular and nervous system. UCR::Vicerrectoría de Docencia::Salud::Facultad de Medicina::Escuela de Medicina

Synapsins (Syns) are an evolutionarily conserved family of synaptic vesicle-associated proteins related to fine tuning of synaptic transmission. Studies with mammals have partially clarified the different roles of Syns; however, the presence of different genes and isoforms and the development of compensatory mechanisms hinder accurate data interpretation. Here, we use a simple in vitromonosynaptic Helix neuron connection, reproducing an in vivo physiological connection as a reliable experimental model to investigate the effects of Syn knockdown. Cells overexpressing an antisense construct against Helix Syn showed a timedependent decrease of Syn immunostaining, confirming protein loss. At the morphological level, Syn-silenced cells showed a reduction in neurite linear outgrowth and branching and in the size and number of synaptic varicosities. Functionally, Syn-silenced cells presented a reduced ability to form synaptic connections; however, functional chemical synapses showed similar basal excitatory postsynaptic potentials and similar short-term plasticity paradigms. In addition, Syn-silenced cells presented faster neurotransmitter release and decreased postsynaptic response toward the end of long tetanic presynaptic stimulations, probably related to an impairment of the synaptic vesicle trafficking resulting from a different vesicle handling, with an increased readily releasable pool and a compromised reserve pool. Compagnia di San Paolo/[]//Italia Italian Ministry of the University and Research/[PRIN 2009]//Italia UCR::Vicerrectoría de Docencia::Salud::Facultad de Medicina::Escuela de Medicina

Human endothelial EA.hy926 cells were incubated with BaP1, a hemorrhagic metalloproteinase purified from Bothrops asper snake venom. Since the first hour of incubation with the proteinase, cells started showing DNA fragmentation, detected by a terminal deoxynucleotidyl transferase-mediated dUDP nick-end labeling (TUNEL)-based photometric enzyme-linked immunosorbent assay (ELISA). At later times, DNA fragments were predominantly located outside the cells, evidencing plasma membrane rupture. DNA fragmentation was completely abolished by Batimastat, a potent inhibitor of metalloproteinase enzymatic activity. Apoptosis induced by BaP1 on endothelial cells was independent of two Bcl-2 family members (anti-apototic Bcl-xL and pro-apoptotic Bax), that did not show any changes in their expression during a 24 h-treatment period. Interestingly, IkappaBalpha, an inhibitor of NFkappaB, decreased after 24 h of treatment, suggesting further activation of the transcription factor. When some elements of the apoptotic extrinsic pathway were assessed, it was observed that procaspase-8 completely disappeared after 24 h of treatment with BaP1, probably indicating its activation by a death receptor, whereas caspase-8 inhibitor, cellular FLICE-inhibitory protein (cFLIP(L)), increased its expression since the first hours of BaP1 incubation. In conclusion, treatment of human endothelial cells with BaP1 induces apoptosis/anoikis, independently of Bcl-2 family members Bax and Bcl-xL and associated with caspase-8 activation and cFLIP(L) up-regulation. Apoptosis was completely dependent on BaP1 enzymatic activity. Similarities between this and other endothelial cell anoikis-related systems suggest that BaP1 and other snake venom metalloproteinases may be useful experimental tools in the study of death-related events that occur when adherent cells loose contact with extracellular matrix. Wellcome Trus/[062043]//Estados Unidos Universidad de Costa Rica/[741-A0-049]/UCR/Costa Rica UCR::Vicerrectoría de Investigación::Unidades de Investigación::Ciencias de la Salud::Instituto Clodomiro Picado (ICP)