From osmotic to biomechanical stress - The role of nuclear factor of activated t - cells 5 in determining the vascular smooth muscle cell phenotype

Nuclear factor of activated T-cells 5 (NFAT5) is a well-known osmoprotective transcription factor the amount and nuclear distribution of which is increased in a hyperosmolaric environment. Recently, NFAT5 was shown to control the phenotype of vascular smooth muscle cells (VSMCs) in the context of arteriosclerosis and neointimal hyperplasia by regulating the expression of smooth muscle cell differentiation markers. As an increase in wall stress is a wellknown determinant of the VSMC phenotype, it was hypothesized in this thesis, that wall stress or stretch may affect NFAT5 activity as well. Furthermore, this study tried to reveal potential signal transduction pathways leading to the activation of NFAT5 in stretch-stimulated VSMCs and explore the function of NFAT5 in the context of vascular remodeling.