S1P (sphingosine-1-phosphate), produced by Sphk1 (sphingosine kinase 1), plays a pivotal role in the pathogenesis of hypertension and downstream organ damage, as it controls vascular tone and regulates cardiac remodeling.
Using Western blotting, flow cytometry and mass spectrometry approaches, we show that hypertension stimulates a sphingosine kinase 1 (SphK1)-dependent increase of cerebral S1P concentrations in a mouse model of angiotensin II (AngII)-induced hypertension.
Therefore we further investigated the role of miR-1 in modulating SphK1 expression and characterized its effects on the phenotype of pulmonary artery smooth muscle cells (PASMCs) and the development of experimental pulmonary hypertension in vivo.
While Sphk1 is important in mediating vasoconstriction in hypertension, Sphk1<sup>-/-</sup> mice were characterized by enhanced endothelial dysfunction, suggesting a local protective role of Sphk1 in the endothelium.
Sphingosine kinase 1 (SphK1) knockout mice are protected against pulmonary hypertension and expression levels of the enzyme are increased in the lungs of pulmonary arterial hypertensive (PAH) patients.
The results show that lack of SphK1 expression did not exacerbate angiotensin II (Ang II)-induced acute hypertension, whereas celecoxib, a COX-2 inhibitor, augmented and sustained higher BP in mice.