Pulmonary arterial hypertension (PAH) is a devastating disease, characterized by obstructive pulmonary vascular remodelling ultimately leading to right ventricular (RV) failure and death. Disturbed... Show morePulmonary arterial hypertension (PAH) is a devastating disease, characterized by obstructive pulmonary vascular remodelling ultimately leading to right ventricular (RV) failure and death. Disturbed transforming growth factor-beta (TGF-beta)/bone morphogenetic protein (BMP) signalling, endothelial cell dysfunction, increased proliferation of smooth muscle cells and fibroblasts, and inflammation contribute to this abnormal remodelling. Peptidyl-prolyl isomerase Pin1 has been identified as a critical driver of proliferation and inflammation in vascular cells, but its role in the disturbed TGF-beta/BMP signalling, endothelial cell dysfunction, and vascular remodelling in PAH is unknown. Here, we report that Pin1 expression is increased in cultured pulmonary microvascular endothelial cells (MVECs) and lung tissue of PAH patients. Pin1 inhibitor, juglone significantly decreased TGF-beta signalling, increased BMP signalling, normalized their hyper-proliferative, and inflammatory phenotype. Juglone treatment reversed vascular remodelling through reducing TGF-beta signalling in monocrotaline + shunt-PAH rat model. Juglone treatment decreased Fulton index, but did not affect or harm cardiac function and remodelling in rats with RV pressure load induced by pulmonary artery banding. Our study demonstrates that inhibition of Pin1 reversed the PAH phenotype in PAH MVECs in vitro and in PAH rats in vivo, potentially through modulation of TGF-beta/BMP signalling pathways. Selective inhibition of Pin1 could be a novel therapeutic option for the treatment of PAH. Show less
In this thesis, several critical time-points of human germ cell development are addressed.In Chapter 2, we adopted a culture system combining features of human embryonicstem cells (hESCs)... Show moreIn this thesis, several critical time-points of human germ cell development are addressed.In Chapter 2, we adopted a culture system combining features of human embryonicstem cells (hESCs) derivation, by supplementation with Activin A, and extended blastocyst culture in vitro to examine lineage segregation in human blastocyst outgrowths. In Chapter 3, migratory and early post-migratory hPGCs were extensively characterized in a rare 4.5 week-old human embryo. In Chapter 4 an extensive characterization of the expression pattern and subcellularcompartmentalization of the PIWIL protein family during human embryonic development and spermatogenesis was performed.Several studies suggest that at some point during the transition from naïve to primed, pluripotency competency for PGC induction is acquired in culture, in parallel with what happens in vivo. In Chapter 5, requirement of BMP-SMAD signalling to keep pluripotency in naïve and ground state culture conditions was analysed. Show less
