Endothelial mechanosensing pathway identified as driver of pulmonary fibrosis

A new study using single-cell multiomics has identified a previously unrecognized mechanosensitive signaling pathway in vascular endothelial cells that is associated with pulmonary fibrosis, offering potential new targets for therapeutic intervention.

Pulmonary fibrosis is a progressive interstitial lung disease characterized by excessive extracellular matrix deposition, architectural distortion and declining lung function. While epithelial injury and fibroblast activation have been widely studied, the role of endothelial mechanobiology has remained less clearly defined.

To address this gap, a research team led by Lanlan Zhang, PhD, in the department of respiratory and critical care medicine at West China Hospital of Sichuan University in China, employed integrated single-cell multiomics approaches.

The study, published March 20, 2026, in Nature, combined transcriptomic and epigenomic profiling of human pulmonary fibrosis samples alongside experimental models induced by bleomycin or silica exposure. This approach enabled high-resolution mapping of cell-type–specific signaling pathways involved in fibrotic remodeling.

Zhang, along with senior contributions from Rongchang Chen, M.D., Bi-Sen Ding, Ph.D., and colleagues, examined the molecular mechanisms underlying fibrotic progression in the lung. The investigators focused on how endothelial cells, which have long been recognized as contributors to fibrosis through paracrine signaling, respond to mechanical stress within the diseased lung microenvironment.

The analysis identified upregulation of the mechanosensitive ion channel protein piezo1 in endothelial cells as a key feature of fibrotic lung tissue. Piezo1 is known to respond to mechanical forces such as stretch and shear stress, suggesting that physical changes in lung architecture during fibrosis may directly influence endothelial signaling pathways.

The study authors revealed that activation of piezo1 promotes downstream signaling involving interleukin-33 (IL-33), a cytokine implicated in inflammatory and fibrotic responses. Together, these findings define a piezo1–IL-33 signaling axis that appears to link mechanical stress to pro-fibrotic molecular pathways.

Furthermore, authors noted functional experiments provided additional support for the pathway’s role in disease progression. In mouse models of pulmonary fibrosis, endothelial-specific deletion of piezo1 significantly attenuated fibrotic remodeling following bleomycin exposure, demonstrating that the pathway is not only associated with fibrosis but functionally contributes to its development.

The findings suggest that endothelial cells act as mechanosensors within the fibrotic lung, translating mechanical cues into biochemical signals that promote inflammation and extracellular matrix deposition. This link helps explain how progressive tissue stiffening — a hallmark of fibrosis — may further accelerate disease through a feedback loop of mechanotransduction and cellular activation.

The study highlights the potential for targeting endothelial signaling pathways in pulmonary fibrosis, a disease for which current treatments remain limited. Existing antifibrotic therapies such as the more common Ofev (nintedanib) and Esbriet (pirfenidone) slow disease progression but do not reverse established fibrosis, underscoring the need for new therapeutic strategies.

By identifying piezo1 as a central mediator of endothelial responses to mechanical stress, the research provides a possible target for intervention aimed at disrupting the signaling cascade that drives fibrotic progression. Modulating IL-33 signaling may represent another potential approach, given its role as a downstream effector in the identified pathway.

According to the authors, the use of single-cell multiomics was a key strength of the study, allowing investigators to dissect complex cellular interactions within the lung microenvironment at high resolution. This approach enabled the identification of cell-type–specific signaling pathways that might not be apparent in bulk tissue analyses.

However, the authors noted that further research will be needed to validate the findings in human disease and to determine whether targeting the piezo1–IL-33 axis can translate into clinical benefit. Therefore, additional studies exploring the safety and efficacy of modulating this pathway will be required before potential therapies can be developed.

Still, the findings add to a growing body of literature emphasizing the importance of mechanobiology in pulmonary fibrosis.

For clinicians and researchers, the study provides new insight into the cellular and molecular drivers of pulmonary fibrosis and identifies a novel pathway that could inform future therapeutic development.