Pulmonary arterial hypertension (PAH) happens when the blood vessels in the lungs become too narrow and stiff. This raises pressure in the lungs and puts strain on the heart. In a collaborative study, scientists from Inserm and Université Paris-Saclay in France, together with researchers from the Institute for Lung Health (ILH) in Germany, discovered that a blood protein called BMP-9 plays a key role in keeping the lung’s blood vessels healthy. BMP-9 sends signals to the cells lining the blood vessels through receptors called ALK1 and BMPR-II. These signals tell the vessels how to grow and stay organized. When BMP-9 signals are weak, the vessels grow in a disorganized way which may make Pulmonary arterial Hypertension worse. The researchers also found that BMP-9 works with another growth factor, VEGF, to keep a good balance between growing new blood vessels and preventing too much growth.
Why this matters for people with pulmonary arterial hypertension
- Helps explain the disease: Shows why blood vessels in Pulmonary Arterial Hypertension change their shape and become too narrow.
- Points to new treatments: Boosting BMP-9 signals might help protect or even repair the lung’s blood vessels.
- Hope for the future: This research supports the idea that we can go beyond symptom relief and slow or stop Pulmonary Arterial Hypertension progression.
Summary by Alena Adarbehova, volunteer for the Alliance for Pulmonary Hypertension
Read more at this link on the Proceedings of the National Academy of Sciences of the United States of America (PNAS)
Citation
Berrebeh N, Mbouamboua Y, Thuillet R, Ottaviani M, et al. Bone morphogenetic protein-9 controls pulmonary vascular growth and remodeling. Proc Natl Acad Sci U S A. 2025 Jul;122(26):e2410229122. doi: 10.1073/pnas.2410229122. Epub 2025 Jun 23. PubMed