Pulmonary hypertension is a complex disease that affects multiple vascular cell types, and mircoRNAs (miRNAs) have been implicated in the pathogenesis of this condition. In this episode, Stephen Chan discusses how his group used network theory to identify miRNA-130/301 as a regulator of a system of miRNAs that promote the development of pulmonary hypertension. Furthermore, inhibition of miR130/301 prevented the development on pulmonary hypertension in a hypoxic murine model. The results of this study support the use of network analysis for identifying complex miRNA-regulated pathways involved in disease manifestations.
Development of the vascular disease pulmonary hypertension (PH) involves disparate molecular pathways that span multiple cell types. MicroRNAs (miRNAs) may coordinately regulate PH progression, but the integrative functions of miRNAs in this process have been challenging to define with conventional approaches. Here, analysis of the molecular network architecture specific to PH predicted that the miR-130/301 family is a master regulator of cellular proliferation in PH via regulation of subordinate miRNA pathways with unexpected connections to one another. In validation of this model, diseased pulmonary vessels and plasma from mammalian models and human PH subjects exhibited upregulation of miR-130/301 expression. Evaluation of pulmonary arterial endothelial cells and smooth muscle cells revealed that miR-130/301 targeted PPARγ with distinct consequences. In endothelial cells, miR-130/301 modulated apelin-miR-424/503-FGF2 signaling, while in smooth muscle cells, miR-130/301 modulated STAT3-miR-204 signaling to promote PH-associated phenotypes. In murine models, induction of miR-130/301 promoted pathogenic PH-associated effects, while miR-130/301 inhibition prevented PH pathogenesis. Together, these results provide insight into the systems-level regulation of miRNA-disease gene networks in PH with broad implications for miRNA-based therapeutics in this disease. Furthermore, these findings provide critical validation for the evolving application of network theory to the discovery of the miRNA-based origins of PH and other diseases.
Thomas Bertero, Yu Lu, Sofia Annis, Andrew Hale, Balkrishen Bhat, Rajan Saggar, Rajeev Saggar, W. Dean Wallace, David J. Ross, Sara O. Vargas, Brian B. Graham, Rahul Kumar, Stephen M. Black, Sohrab Fratz, Jeffrey R. Fineman, James D. West, Kathleen J. Haley, Aaron B. Waxman, B. Nelson Chau, Katherine A. Cottrill, Stephen Y. Chan