Staff member

Javier Selva Sánchez

Project Manager
Projects Office Unit
+34 934 031 198
Staff member publications

Moles, Ernest, Valle-Delgado, Juan José, Urbán, Patricia, Azcárate, Isabel G., Bautista, José M., Selva, Javier, Egea, Gustavo, Ventura, Salvador, Fernàndez-Busquets, Xavier, (2015). Possible roles of amyloids in malaria pathophysiology Future Science OA , 1, (2), FSO43

The main therapeutic and prophylactic tools against malaria have been locked for more than a century in the classical approaches of using drugs targeting metabolic processes of the causing agent, the protist Plasmodium spp., and of designing vaccines against chosen antigens found on the parasite’s surface. Given the extraordinary resources exhibited by Plasmodium to escape these traditional strategies, which have not been able to free humankind from the scourge of malaria despite much effort invested in them, new concepts have to be explored in order to advance toward eradication of the disease. In this context, amyloid-forming proteins and peptides found in the proteome of the pathogen should perhaps cease being regarded as mere anomalous molecules. Their likely functionality in the pathophysiology of Plasmodium calls for attention being paid to them as a possible Achilles’ heel of malaria. Here we will give an overview of Plasmodium-encoded amyloid-forming polypeptides as potential therapeutic targets and toxic elements, particularly in relation to cerebral malaria and the blood–brain barrier function. We will also discuss the recent finding that the genome of the parasite contains an astonishingly high proportion of prionogenic domains.

Keywords: Amyloids, Intrinsically unstructured proteins, Malaria, Prions

Crosas-Molist, E., Meirelles, T., López-Luque, J., Serra-Peinado, C., Selva, J., Caja, L., Gorbenko Del Blanco, D., Uriarte, J. J., Bertran, E., Mendizábal, Y., Hernández, V., García-Calero, C., Busnadiego, O., Condom, E., Toral, D., Castellà, M., Forteza, A., Navajas, D., Sarri, E., Rodríguez-Pascual, F., Dietz, H. C., Fabregat, I., Egea, G., (2015). Vascular smooth muscle cell phenotypic changes in patients with marfan syndrome Arteriosclerosis, Thrombosis, and Vascular Biology , 35, (4), 960-972

Objective - Marfan's syndrome is characterized by the formation of ascending aortic aneurysms resulting from altered assembly of extracellular matrix microfibrils and chronic tissue growth factor (TGF)-β signaling. TGF-β is a potent regulator of the vascular smooth muscle cell (VSMC) phenotype. We hypothesized that as a result of the chronic TGF-β signaling, VSMC would alter their basal differentiation phenotype, which could facilitate the formation of aneurysms. This study explores whether Marfan's syndrome entails phenotypic alterations of VSMC and possible mechanisms at the subcellular level. Approach and Results - Immunohistochemical and Western blotting analyses of dilated aortas from Marfan patients showed overexpression of contractile protein markers (α-smooth muscle actin, smoothelin, smooth muscle protein 22 alpha, and calponin-1) and collagen I in comparison with healthy aortas. VSMC explanted from Marfan aortic aneurysms showed increased in vitro expression of these phenotypic markers and also of myocardin, a transcription factor essential for VSMC-specific differentiation. These alterations were generally reduced after pharmacological inhibition of the TGF-β pathway. Marfan VSMC in culture showed more robust actin stress fibers and enhanced RhoA-GTP levels, which was accompanied by increased focal adhesion components and higher nuclear localization of myosin-related transcription factor A. Marfan VSMC and extracellular matrix measured by atomic force microscopy were both stiffer than their respective controls. Conclusions - In Marfan VSMC, both in tissue and in culture, there are variable TGF-β-dependent phenotypic changes affecting contractile proteins and collagen I, leading to greater cellular and extracellular matrix stiffness. Altogether, these alterations may contribute to the known aortic rigidity that precedes or accompanies Marfan's syndrome aneurysm formation.

Keywords: Actin, Aortic aneurysms, Aortic stiffness, Extracellular matrix, Focal adhesion, Myocardin, RhoA, TGF-β