Bradykinin (BK) induces an epithelial- mesenchymal transition in nephrogenic ureteric bud (UB) cells

EDITH DEL VALLE GUAYTIMA; YAMILA ROMINA BRANDÁN; NICOLÁS OCTAVIO FAVALE; NORMA B. STERIN-SPEZIALE; MARÍA GABRIELA MÁRQUEZ

Ciudad de Mendoza, Mendoza

Congreso; XLVIII Reunión Anual Sociedad Argentina de Investigación en Bioquímica y Biología Molecular; 2012

Sociedad Argentina de Investigación en Bioquímica y Biología Molecular (SAIB)

We studied the effect of BK on renal papillary collecting duct/UB cells of 7 days-old rats. In mammals, nephrogenesis is completed posnatally. Cultured UB cells form large colonies with a well spread morphology and lamellipodia in the peripheral cells showing the phenotype of a migratory sheet of epithelial cells. UB cells interact with each other and with the substratum through adherens junctions and focal adhesions (FA) immunostained with vinculin. BK treatment resulted in cell scattering and FA disipation, accompanied by changes in cellular morphology from a spread to a more rounded shape. We also observed irregular cells with lamellipodia and filopodia making contacts with neighbouring cells. Pre-treatment of cells with a selective BK-B2 receptor antagonist, Hoe 140, avoids cell scattering and FA dissipation. We interpret that in the absence of BK, UB cells form colonies and migrate collectively, and this behavior could explain the collective advance of the UB from papilla to renal cortex which take place in nephrogenesis. Taking into account that BK-B2 mRNA levels are higher in newborn kidney, we propose that in kidney development BK induces epithelial- mesenchymal transition, which causes to the cells lose their junctional interactions and become migratory mesenchymal-like cells, which finally could undergoes mesenchymal?epithelial conversion to give rise kidney tubules.