Biomechanical stress provides a second hit in the establishment of BMP/TGFβ-related vascular disorders

Christian Hiepen1, Jerome Jatzlau1, Petra Knaus1

  • 1Freie Universität Berlin, Institute for Chemistry and Biochemistry, 14195 Berlin, Germany.

Cell Stress
|February 12, 2020
PubMed

Insights

Mutations in Bone Morphogenetic Protein type II receptor (BMPR2) cause pulmonary arterial hypertension (PAH). BMPR2 downregulation increases TGFβ signaling, impacting endothelial cell pathobiology and cardiovascular disease progression.

Area of Science:

  • Cardiovascular Biology
  • Molecular Medicine
  • Cell Biology

Background:

  • Cardiovascular disorders are a leading cause of mortality and rising healthcare costs.
  • Understanding molecular mechanisms in early cardiovascular disease onset is vital for new therapies.
  • Pulmonary arterial hypertension (PAH) is a severe genetic vascular disorder.

Purpose of the Study:

  • To investigate the early molecular steps in hereditary PAH (HPAH) using CRISPR/Cas9 gene editing.
  • To elucidate the role of Bone Morphogenetic Protein type II receptor (BMPR2) in PAH.
  • To understand how BMPR2 mutations affect endothelial cell (EC) signaling and pathobiology.

Main Methods:

  • CRISPR/Cas9 gene editing in human endothelial cells (ECs).
  • Analysis of SMAD signaling pathways (SMAD1/5 and SMAD2/3).
  • Investigation of extracellular matrix (ECM) remodeling and biomechanics.

Main Results:

  • Mutations in BMPR2 lead to its downregulation, priming for HPAH.
  • Downregulated BMPR2 alters SMAD signaling, with increased SMAD1/5 and SMAD2/3 responses.
  • ECs with BMPR2 mutations exhibit increased susceptibility to TGFβ signaling due to ECM remodeling and biomechanics.

Conclusions:

  • BMPR2 functions not only as a BMP receptor but also as a crucial gatekeeper against excessive TGFβ signaling in ECs.
  • BMPR2 dysfunction is a key factor in the pathobiology of PAH.
  • These findings offer insights into therapeutic strategies for cardiovascular diseases, particularly PAH.