SphK1/S1P mediates TGF-β1-induced proliferation of pulmonary artery smooth muscle cells and its potential mechanisms


The upregulation of Sphingosine kinase 1 (SphK1) expression and accompanied sphingosine-1-phosphate (S1P) production have been reported to contribute to the proliferation of pulmonary artery smooth muscle cells (PASMC) and pulmonary arterial remodeling. However, the molecular mechanisms of SphK1/S1P upregulation in PASMC and the specific mechanisms of how SphK1/S1P pathway promotes PASMC proliferation remain largely unclear. This study aims to address these issues. Here, we demonstrated that TGF-β1 significantly upregulated SphK1 expression and S1P production by promoting the phosphorylation of Smad2/3 in PASMC. Further study indicated that SphK1/S1P pathway mediated TGF-β1-induced Notch3 activation in PASMC. In addition, we showed that TGF-β1 significantly induced proliferation of PASMC, while pre-inhibition of Smad2/3 phosphorylation with SB431542 or silencing SphK1 using small interfering RNA in advance, or pre-blocking Notch3 pathway with N-[N-(3,5-difluorophenacetyl)-L-alanyl]-S-phenylglycine t-butyl ester (DAPT), attenuated TGF-β1-induced PASMC proliferation. Taken together, our study indicates that Smad2/3/SphK1/S1P/Notch3 pathway mediates TGF-β1-induced PASMC proliferation and suggests this pathway as a potential therapeutic target in the prevention and treatment of pulmonary hypertension.

Read the full article online


Muscles and Muscle Cell Contractility


Wei Feng, Fangwei Li, Wenhua Shi, Cui Zhai, Shaojun Li, Yanting Zhu, Xin Yan, Qingting Wang, Lu Liu, Xinming Xie, Manxiang Li

Published in:

Pulmonary Circulation Vol 9: No 1 cover image

March 2019

Pulmonary Circulation Vol 9: No 1

View this journal

Our research platform is the world.

Through worldwide collaboration, we can begin to answer the question of a global disease.

Join the PVRI