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An endothelial apelin-FGF link mediated by miR-424 and miR-503 is disrupted in pulmonary arterial hypertension


Pulmonary arterial hypertension (PAH) is characterized by vascular remodeling associated with obliteration of pulmonary arterioles and formation of plexiform lesions composed of hyperproliferative endothelial and vascular smooth-muscle cells. Here we describe a microRNA (miRNA)-dependent association between apelin (APLN) and fibroblast growth factor 2 (FGF2) signaling in pulmonary artery endothelial cells (PAECs). APLN deficiency in these cells led to increased expression of FGF2 and its receptor FGFR1 as a consequence of decreased expression of miR-424 and miR-503, which directly target FGF2 and FGFR1. miR-424 and miR-503 were downregulated in PAH, exerted antiproliferative effects in PAECs and inhibited the capacity of PAEC-conditioned medium to induce the proliferation of pulmonary artery smooth-muscle cells. Reconstitution of miR-424 and miR-503 in vivo ameliorated pulmonary hypertension in experimental models. These studies identify an APLN-dependent miRNA-FGF signaling axis needed for the maintenance of pulmonary vascular homeostasis.

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Figure 1: APLN downregulates FGF2 expression in PAECs in an miRNA-dependent manner.
Figure 2: The APLN-FGF2 axis is mediated by APLN-regulated expression of miR-424 and miR-503.
Figure 3: miR-424 and miR-503 regulate FGF2 and FGFR1 expression and signaling.
Figure 4: Downregulation of miR-424 and miR-503 in PAH is associated with increased FGF2 and FGFR1 expression.
Figure 5: Endothelial miR-424 and miR-503 regulate PAEC proliferation and migration and induce paracrine inhibition of PASMC proliferation.
Figure 6: miR-424 and miR-503 overexpression ameliorate experimental pulmonary hypertension models in rats.

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  1. Tuder, R.M., Marecki, J.C., Richter, A., Fijalkowska, I. & Flores, S. Pathology of pulmonary hypertension. Clin. Chest Med. 28, 23–42, vii (2007).

    Article  Google Scholar 

  2. Humbert, M. et al. Cellular and molecular pathobiology of pulmonary arterial hypertension. J. Am. Coll. Cardiol. 43, 13S–24S (2004).

    CAS  Article  Google Scholar 

  3. Hassoun, P.M. et al. Inflammation, growth factors, and pulmonary vascular remodeling. J. Am. Coll. Cardiol. 54, S10–S19 (2009).

    CAS  Article  Google Scholar 

  4. Schermuly, R.T., Ghofrani, H.A., Wilkins, M.R. & Grimminger, F. Mechanisms of disease: pulmonary arterial hypertension. Nat. Rev. Cardiol. 8, 443–455 (2011).

    CAS  Article  Google Scholar 

  5. Izikki, M. et al. Endothelial-derived FGF2 contributes to the progression of pulmonary hypertension in humans and rodents. J. Clin. Invest. 119, 512–523 (2009).

    CAS  Article  Google Scholar 

  6. Eddahibi, S. et al. Cross talk between endothelial and smooth muscle cells in pulmonary hypertension: critical role for serotonin-induced smooth muscle hyperplasia. Circulation 113, 1857–1864 (2006).

    CAS  Article  Google Scholar 

  7. Dewachter, L. et al. Angiopoietin/Tie2 pathway influences smooth muscle hyperplasia in idiopathic pulmonary hypertension. Am. J. Respir. Crit. Care Med. 174, 1025–1033 (2006).

    CAS  Article  Google Scholar 

  8. Chandra, S.M. et al. Disruption of the apelin-APJ system worsens hypoxia-induced pulmonary hypertension. Arterioscler. Thromb. Vasc. Biol. 31, 814–820 (2011).

    CAS  Article  Google Scholar 

  9. Alastalo, T.P. et al. Disruption of PPARγ/β-catenin-mediated regulation of apelin impairs BMP-induced mouse and human pulmonary arterial EC survival. J. Clin. Invest. 121, 3735–3746 (2011).

    CAS  Article  Google Scholar 

  10. Sheikh, A.Y. et al. In vivo genetic profiling and cellular localization of apelin reveals a hypoxia-sensitive, endothelial-centered pathway activated in ischemic heart failure. Am. J. Physiol. Heart Circ. Physiol. 294, H88–H98 (2008).

    CAS  Article  Google Scholar 

  11. Hosoya, M. et al. Molecular and functional characteristics of APJ. Tissue distribution of mRNA and interaction with the endogenous ligand apelin. J. Biol. Chem. 275, 21061–21067 (2000).

    CAS  Article  Google Scholar 

  12. Regard, J.B., Sato, I.T. & Coughlin, S.R. Anatomical profiling of G protein–coupled receptor expression. Cell 135, 561–571 (2008).

    CAS  Article  Google Scholar 

  13. Goetze, J.P. et al. Apelin: a new plasma marker of cardiopulmonary disease. Regul. Pept. 133, 134–138 (2006).

    CAS  Article  Google Scholar 

  14. Tuder, R.M., Groves, B., Badesch, D.B. & Voelkel, N.F. Exuberant endothelial cell growth and elements of inflammation are present in plexiform lesions of pulmonary hypertension. Am. J. Pathol. 144, 275–285 (1994).

    CAS  PubMed  PubMed Central  Google Scholar 

  15. Masri, F.A. et al. Hyperproliferative apoptosis-resistant endothelial cells in idiopathic pulmonary arterial hypertension. Am. J. Physiol. Lung Cell. Mol. Physiol. 293, L548–L554 (2007).

    CAS  Article  Google Scholar 

  16. Benisty, J.I. et al. Elevated basic fibroblast growth factor levels in patients with pulmonary arterial hypertension. Chest 126, 1255–1261 (2004).

    CAS  Article  Google Scholar 

  17. Falcão-Pires, I. et al. Apelin decreases myocardial injury and improves right ventricular function in monocrotaline-induced pulmonary hypertension. Am. J. Physiol. Heart Circ. Physiol. 296, H2007–H2014 (2009).

    Article  Google Scholar 

  18. Charo, D.N. et al. Endogenous regulation of cardiovascular function by apelin-APJ. Am. J. Physiol. Heart Circ. Physiol. 297, H1904–H1913 (2009).

    CAS  Article  Google Scholar 

  19. Habata, Y. et al. Apelin, the natural ligand of the orphan receptor APJ, is abundantly secreted in the colostrum. Biochim. Biophys. Acta 1452, 25–35 (1999).

    CAS  Article  Google Scholar 

  20. Chamorro-Jorganes, A. et al. MicroRNA-16 and microRNA-424 regulate cell-autonomous angiogenic functions in endothelial cells via targeting vascular endothelial growth factor receptor-2 and fibroblast growth factor receptor-1. Arterioscler. Thromb. Vasc. Biol. 31, 2595–2606 (2011).

    CAS  Article  Google Scholar 

  21. Murakami, M. et al. The FGF system has a key role in regulating vascular integrity. J. Clin. Invest. 118, 3355–3366 (2008).

    CAS  Article  Google Scholar 

  22. Stenmark, K.R., Meyrick, B., Galie, N., Mooi, W.J. & McMurtry, I.F. Animal models of pulmonary arterial hypertension: the hope for etiological discovery and pharmacological cure. Am. J. Physiol. Lung Cell. Mol. Physiol. 297, L1013–L1032 (2009).

    CAS  Article  Google Scholar 

  23. Taraseviciene-Stewart, L. et al. Inhibition of the VEGF receptor 2 combined with chronic hypoxia causes cell death–dependent pulmonary endothelial cell proliferation and severe pulmonary hypertension. FASEB J. 15, 427–438 (2001).

    CAS  Article  Google Scholar 

  24. Tu, L. et al. Autocrine fibroblast growth factor-2 signaling contributes to altered endothelial phenotype in pulmonary hypertension. Am. J. Respir. Cell Mol. Biol. 45, 311–322 (2011).

    CAS  Article  Google Scholar 

  25. Masri, B., Morin, N., Cornu, M., Knibiehler, B. & Audigier, Y. Apelin (65–77) activates p70 S6 kinase and is mitogenic for umbilical endothelial cells. FASEB J. 18, 1909–1911 (2004).

    CAS  Article  Google Scholar 

  26. Eyries, M. et al. Hypoxia-induced apelin expression regulates endothelial cell proliferation and regenerative angiogenesis. Circ. Res. 103, 432–440 (2008).

    CAS  Article  Google Scholar 

  27. Kälin, R.E. et al. Paracrine and autocrine mechanisms of apelin signaling govern embryonic and tumor angiogenesis. Dev. Biol. 305, 599–614 (2007).

    Article  Google Scholar 

  28. del Toro, R. et al. Identification and functional analysis of endothelial tip cell-enriched genes. Blood 116, 4025–4033 (2010).

    CAS  Article  Google Scholar 

  29. Kasai, A. et al. Apelin is a crucial factor for hypoxia-induced retinal angiogenesis. Arterioscler. Thromb. Vasc. Biol. 30, 2182–2187 (2010).

    CAS  Article  Google Scholar 

  30. Kasai, A. et al. Retardation of retinal vascular development in apelin-deficient mice. Arterioscler. Thromb. Vasc. Biol. 28, 1717–1722 (2008).

    CAS  Article  Google Scholar 

  31. Kidoya, H., Naito, H. & Takakura, N. Apelin induces enlarged and nonleaky blood vessels for functional recovery from ischemia. Blood 115, 3166–3174 (2010).

    CAS  Article  Google Scholar 

  32. Caruso, P. et al. Dynamic changes in lung microRNA profiles during the development of pulmonary hypertension due to chronic hypoxia and monocrotaline. Arterioscler. Thromb. Vasc. Biol. 30, 716–723 (2010).

    CAS  Article  Google Scholar 

  33. Forrest, A.R. et al. Induction of microRNAs, mir-155, mir-222, mir-424 and mir-503, promotes monocytic differentiation through combinatorial regulation. Leukemia 24, 460–466 (2010).

    CAS  Article  Google Scholar 

  34. Sarkar, S., Dey, B.K. & Dutta, A. MiR-322/424 and -503 are induced during muscle differentiation and promote cell cycle quiescence and differentiation by down-regulation of Cdc25A. Mol. Biol. Cell 21, 2138–2149 (2010).

    CAS  Article  Google Scholar 

  35. Ghosh, G. et al. Hypoxia-induced microRNA-424 expression in human endothelial cells regulates HIF-alpha isoforms and promotes angiogenesis. J. Clin. Invest. 120, 4141–4154 (2010).

    CAS  Article  Google Scholar 

  36. Comhair, S.A. et al. Human primary lung endothelial cells in culture. Am. J. Respir. Cell Mol. Biol. 46, 723–730 (2012).

    CAS  Article  Google Scholar 

  37. Aytekin, M. et al. High levels of hyaluronan in idiopathic pulmonary arterial hypertension. Am. J. Physiol. Lung Cell. Mol. Physiol. 295, L789–L799 (2008).

    CAS  Article  Google Scholar 

  38. Chun, H.J. et al. Apelin signaling antagonizes Ang II effects in mouse models of atherosclerosis. J. Clin. Invest. 118, 3343–3354 (2008).

    CAS  PubMed  PubMed Central  Google Scholar 

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We thank M. Simons and P. Yu for critical reading of the manuscript, R. Homer for pathology slide review, T. Quertermous (Stanford University) for the Apln-null mice, P. Lee and Y. Zhang for guidance with the lentiviral work and the Yale Center for Genome Analysis for miRNA array analyses. This study was supported by grants from the US National Institutes of Health (HL095654, HL113005 and HL101284 to H.J.C., HL069170 to S.C.E. and HL093362 to D.M.G.), the Howard Hughes Medical Institute (Physician Scientist Early Career Award to H.J.C.), an American Heart Association Grant-in-Aid (12GRNT9410029 to H.J.C.) and the Pfizer ASPIRE Young Investigator Research Award (H.J.C.).

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Authors and Affiliations



J.K. and H.J.C. designed the research. J.K., Y. Kang, Y. Kojima, J.K.L., X.H., D.L.M., H.P. and H.J.C. performed the experiments. M.A.A., S.A.C. and S.C.E. collected and prepared the subject samples. D.M.G. and S.C.E. assisted with data analysis and review of the manuscript. J.K. and H.J.C. prepared the figures. J.K. and H.J.C. wrote the manuscript.

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Correspondence to Hyung J Chun.

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Kim, J., Kang, Y., Kojima, Y. et al. An endothelial apelin-FGF link mediated by miR-424 and miR-503 is disrupted in pulmonary arterial hypertension. Nat Med 19, 74–82 (2013).

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