Molecular Medicine

, Volume 18, Issue 12, pp 1509–1518 | Cite as

High Mobility Group Box 1 Contributes to the Pathogenesis of Experimental Pulmonary Hypertension via Activation of Toll-like Receptor 4

  • Eileen M Bauer
  • Richard Shapiro
  • Han Zheng
  • Ferhaan Ahmad
  • David Ishizawar
  • Suzy A Comhair
  • Serpil C Erzurum
  • Timothy R Billiar
  • Philip M Bauer
Research Article


Survival rates for patients with pulmonary hypertension (PH) remain low, and our understanding of the mechanisms involved are incomplete. Here we show in a mouse model of chronic hypoxia (CH)-induced PH that the nuclear protein and damage-associate molecular pattern molecule (DAMP) high mobility group box 1 (HMGB1) contributes to PH via a Toll-like receptor 4 (TLR4)-dependent mechanism. We demonstrate extranuclear HMGB1 in pulmonary vascular lesions and increased serum HMGB1 in patients with idiopathic pulmonary arterial hypertension. The increase in circulating HMGB1 correlated with mean pulmonary artery pressure. In mice, we similarly detected the translocation and release of HMGB1 after exposure to CH. HMGB1-neutralizing antibody attenuated the development of CH-induced PH, as assessed by measurement of right ventricular systolic pressure, right ventricular hypertrophy, pulmonary vascular remodeling and endothelial activation and inflammation. Genetic deletion of the pattern recognition receptor TLR4, but not the receptor for advanced glycation end products, likewise attenuated CH-induced PH. Finally, daily treatment of mice with recombinant human HMGB1 exacerbated CH-induced PH in wild-type (WT) but not Tlr4−/− mice. These data demonstrate that HMGB1-mediated activation of TLR4 promotes experimental PH and identify HMGB1 and/or TLR4 as potential therapeutic targets for the treatment of PH.



We thank Kevin Tracey (North Shore-LIJ Health System, Feinstein Institute for Medical Research) for providing the HMGB1 neutralizing antibody. We thank Suchitra Barge, Michael Lotze and Lisa Butterfield (University of Pittsburgh) for assistance in obtaining control patient samples. Some of the IPAH patient samples were provided by Cooperative Human Tissue Network, Southern Division, The University of Alabama at Birmingham, under the Pulmonary Hypertension Breakthrough Initiative (PHBI). Funding for the PHBI was provided by the Cardiovascular Medical Research and Education Fund. This work was supported by grants to PM Bauer (R01-HL085134 and NIH R03-HL110794), SC Erzurum (R01-HL60917), TR Billiar (P50-GM53789) and EM Bauer (T32-098036).

Supplementary material

10020_2012_18121509_MOESM1_ESM.pdf (3.7 mb)
High Mobility Group Box 1 Contributes to the Pathogenesis of Experimental Pulmonary Hypertension via Activation of Toll-like Receptor 4


  1. 1.
    Simonneau G, et al. (2004) Clinical classification of pulmonary hypertension. J. Am. Coll. Cardiol. 43:5S–12S.CrossRefGoogle Scholar
  2. 2.
    Humbert M, et al. (2004) Cellular and molecular pathobiology of pulmonary arterial hypertension. J. Am. Coll. Cardiol. 43:13S–24S.CrossRefGoogle Scholar
  3. 3.
    Rabinovitch M. (2008) Molecular pathogenesis of pulmonary arterial hypertension. J. Clin. Invest. 118:2372–9.CrossRefGoogle Scholar
  4. 4.
    Tuder RM, et al. (2009) Development and pathology of pulmonary hypertension. J. Am. Coll. Cardiol. 54:S3–9.CrossRefGoogle Scholar
  5. 5.
    Tuder RM, Marecki JC, Richter A, Fijalkowska I, Flores S. (2007) Pathology of pulmonary hypertension. Clin. Chest Med. 28:23–42, vii.CrossRefGoogle Scholar
  6. 6.
    Michelakis ED, Wilkins MR, Rabinovitch M. (2008) Emerging concepts and translational priorities in pulmonary arterial hypertension. Circulation. 118:1486–95.CrossRefGoogle Scholar
  7. 7.
    Galie N, et al. (2009) A meta-analysis of randomized controlled trials in pulmonary arterial hypertension. Eur. Heart J. 30:394–403.CrossRefGoogle Scholar
  8. 8.
    Macchia A, et al. (2007) A meta-analysis of trials of pulmonary hypertension: a clinical condition looking for drugs and research methodology. Am. Heart J. 153:1037–47.CrossRefGoogle Scholar
  9. 9.
    Bianchi ME. (2007) DAMPs, PAMPs and alarmins: all we need to know about danger. J. Leukoc. Biol. 81:1–5.CrossRefGoogle Scholar
  10. 10.
    Bonaldi T, Langst G, Strohner R, Becker PB, Bianchi ME. (2002) The DNA chaperone HMGB1 facilitates ACF/CHRAC-dependent nucleosome sliding. EMBO J. 21:6865–73.CrossRefGoogle Scholar
  11. 11.
    Park JS, et al. (2006) High mobility group box 1 protein interacts with multiple Toll-like receptors. Am. J. Physiol. Cell Physiol. 290:C917–24.CrossRefGoogle Scholar
  12. 12.
    Park JS, et al. (2004) Involvement of toll-like receptors 2 and 4 in cellular activation by high mobility group box 1 protein. J. Biol. Chem. 279:7370–7.CrossRefGoogle Scholar
  13. 13.
    Hori O, et al. (1995) The receptor for advanced glycation end products (RAGE) is a cellular binding site for amphoterin: mediation of neurite outgrowth and co-expression of rage and amphoterin in the developing nervous system. J. Biol. Chem. 270:25752–61.CrossRefGoogle Scholar
  14. 14.
    Sodhi CP, et al. (2010) Toll-like receptor-4 inhibits enterocyte proliferation via impaired beta-catenin signaling in necrotizing enterocolitis. Gastroenterology. 138:185–96.CrossRefGoogle Scholar
  15. 15.
    Liliensiek B, et al. (2004) Receptor for advanced glycation end products (RAGE) regulates sepsis but not the adaptive immune response. J. Clin. Invest. 113:1641–50.CrossRefGoogle Scholar
  16. 16.
    Yang H, et al. (2004) Reversing established sepsis with antagonists of endogenous high-mobility group box 1. Proc. Natl. Acad. Sci. U. S. A. 101:296–301.CrossRefGoogle Scholar
  17. 17.
    Bauer EM, Shapiro R, Billiar TR, Bauer PM. (2013) High mobility group box 1 inhibits human pulmonary artery endothelial cell migration via a toll-like receptor 4- and interferon response factor 3-dependent mechanism(s). J. Biol. Chem. 288:1365–73.CrossRefGoogle Scholar
  18. 18.
    Bauer EM, et al. (2011) Complement C3 deficiency attenuates chronic hypoxia-induced pulmonary hypertension in mice. PLoS One. 6:e28578.CrossRefGoogle Scholar
  19. 19.
    Troseid M, et al. (2012) Circulating levels of HMGB1 are correlated strongly with MD2 in HIV-infection: possible implication for TLR4-signalling and chronic immune activation. Innate Immun. 2012, Oct 15 [Epub ahead of print].Google Scholar
  20. 20.
    Stoetzer OJ, et al. (2012) Circulating immunogenic cell death biomarkers HMGB1 and RAGE in breast cancer patients during neoadjuvant chemotherapy. Tumour Biol. 2012, Sep 15 [Epub ahead of print].Google Scholar
  21. 21.
    Hashimoto T, et al. (2012) Circulating high-mobility group box 1 and cardiovascular mortality in unstable angina and non-ST-segment elevation myocardial infarction. Atherosclerosis. 221:490–5.CrossRefGoogle Scholar
  22. 22.
    Oktayoglu P, et al. (2012) Elevated serum levels of high mobility group box protein 1 (HMGB1) in patients with ankylosing spondylitis and its association with disease activity and quality of life. Rheumatol. Int. 2012, Nov 10 [Epub ahead of print].Google Scholar
  23. 23.
    Allonso D, et al. (2012) Elevated serum levels of high mobility group box 1 (HMGB1) protein in dengue-infected patients are associated with disease symptoms and secondary infection. J. Clin. Virol. 55:214–9.CrossRefGoogle Scholar
  24. 24.
    Chung HW, et al. (2012) Serum high mobility group box-1 is a powerful diagnostic and prognostic biomarker for pancreatic ductal adenocarcinoma. Cancer Sci. 103:1714–21.CrossRefGoogle Scholar
  25. 25.
    Zickert A, et al. (2012) Renal expression and serum levels of high mobility group box 1 protein in lupus nephritis. Arthritis Res. Ther. 14:R36.CrossRefGoogle Scholar
  26. 26.
    Dupire G, Nicaise C, Gangji V, Soyfoo MS. (2012) Increased serum levels of high-mobility group box 1 (HMGB1) in primary Sjogren’s syndrome. Scand. J. Rheumatol. 41:120–3.CrossRefGoogle Scholar
  27. 27.
    Iannone F, et al. (2008) Bosentan regulates the expression of adhesion molecules on circulating T cells and serum soluble adhesion molecules in systemic sclerosis-associated pulmonary arterial hypertension. Ann. Rheum. Dis. 67:1121–6.CrossRefGoogle Scholar
  28. 28.
    Giaid A, et al. (1993) Expression of endothelin-1 in the lungs of patients with pulmonary hypertension. N. Engl. J. Med. 328:1732–9.CrossRefGoogle Scholar
  29. 29.
    Channick RN, et al. (2001) Effects of the dual endothelin-receptor antagonist bosentan in patients with pulmonary hypertension: a randomised placebo-controlled study. Lancet. 358:1119–23.CrossRefGoogle Scholar
  30. 30.
    Humbert M, et al. (2010) Survival in patients with idiopathic, familial, and anorexigen-associated pulmonary arterial hypertension in the modern management era. Circulation. 122:156–63.CrossRefGoogle Scholar
  31. 31.
    Tuder RM, Groves B, Badesch DB, Voelkel NF. (1994) Exuberant endothelial cell growth and elements of inflammation are present in plexiform lesions of pulmonary hypertension. Am. J. Pathol. 144:275–85.PubMedPubMedCentralGoogle Scholar
  32. 32.
    Hassoun PM, et al. (2009) Inflammation, growth factors, and pulmonary vascular remodeling. J. Am. Coll. Cardiol. 54:S10–9.CrossRefGoogle Scholar
  33. 33.
    Dahl M, Chalmers A, Wade J, Calverley D, Munt B. (1992) Ten year survival of a patient with advanced pulmonary hypertension and mixed connective tissue disease treated with immunosuppressive therapy. J. Rheumatol. 19:1807–9.PubMedGoogle Scholar
  34. 34.
    Friedman DM, Mitnick HJ, Danilowicz D. (1992) Recovery from pulmonary hypertension in an adolescent with mixed connective tissue disease. Ann. Rheum. Dis. 51:1001–4.CrossRefGoogle Scholar
  35. 35.
    Minamino T, et al. (2001) Targeted expression of heme oxygenase-1 prevents the pulmonary inflammatory and vascular responses to hypoxia. Proc. Natl. Acad. Sci. U. S. A. 98:8798–803.CrossRefGoogle Scholar
  36. 36.
    Savale L, et al. (2009) Impact of interleukin-6 on hypoxia-induced pulmonary hypertension and lung inflammation in mice. Respir. Res. 10:6.CrossRefGoogle Scholar
  37. 37.
    Steiner MK, et al. (2009) Interleukin-6 overexpression induces pulmonary hypertension. Circ. Res. 104:236–44.CrossRefGoogle Scholar
  38. 38.
    Kumar H, Kawai T, Akira S. (2011) Pathogen recognition by the innate immune system. Int. Rev. Immunol. 30:16–34.CrossRefGoogle Scholar
  39. 39.
    Matzinger P. (1994) Tolerance, danger, and the extended family. Annu. Rev. Immunol. 12:991–1045.CrossRefGoogle Scholar
  40. 40.
    Klune JR, Dhupar R, Cardinal J, Billiar TR, Tsung A. (2008) HMGB1: endogenous danger signaling. Mol. Med. 14:476–84.CrossRefGoogle Scholar
  41. 41.
    Sadamura Y, et al. (2011) The role of high mobility group box1 in monocrotaline-induced pulmonary hypertension in rats. Am. J. Respir. Crit. Care Med. 183:A3413.Google Scholar
  42. 42.
    Tsung A, et al. (2005) The nuclear factor HMGB1 mediates hepatic injury after murine liver ischemia-reperfusion. J. Exp. Med. 201:1135–43.CrossRefGoogle Scholar
  43. 43.
    Maroso M, et al. (2010) Toll-like receptor 4 and high-mobility group box-1 are involved in ictogenesis and can be targeted to reduce seizures. Nat. Med. 16:413–9.CrossRefGoogle Scholar
  44. 44.
    Mittal D, et al. (2010) TLR4-mediated skin carcinogenesis is dependent on immune and radioresistant cells. EMBO J. 29:2242–52.CrossRefGoogle Scholar
  45. 45.
    Levy RM, et al. (2007) Systemic inflammation and remote organ injury following trauma require HMGB1. Am. J. Physiol. Regul. Integr. Comp. Physiol. 293:R1538–44.CrossRefGoogle Scholar
  46. 46.
    Chen J, et al. (2011) Early interleukin 6 production by leukocytes during ischemic acute kidney injury is regulated by TLR4. Kidney Int. 80:504–15.CrossRefGoogle Scholar
  47. 47.
    Spirig R, et al. (2009) TLR2 and TLR4 agonists induce production of the vasoactive peptide endothelin-1 by human dendritic cells. Mol. Immunol. 46:3178–82.CrossRefGoogle Scholar
  48. 48.
    Liu JQ, Zelko IN, Erbynn EM, Sham JS, Folz RJ. (2006) Hypoxic pulmonary hypertension: role of superoxide and NADPH oxidase (gp91phox). Am. J. Physiol. Lung Cell Mol. Physiol. 290:L2–10.CrossRefGoogle Scholar
  49. 49.
    Yang H, et al. (2010) A critical cysteine is required for HMGB1 binding to Toll-like receptor 4 and activation of macrophage cytokine release. Proc. Natl. Acad. Sci. U. S. A. 107:11942–7.CrossRefGoogle Scholar
  50. 50.
    Andonegui G, et al. (2005) Platelets express functional Toll-like receptor-4. Blood. 106:2417–23.CrossRefGoogle Scholar
  51. 51.
    Katsuoka F, et al. (1997) Type II alveolar epithelial cells in lung express receptor for advanced glycation end products (RAGE) gene. Biochem. Biophys. Res. Commun. 238:512–6.CrossRefGoogle Scholar
  52. 52.
    Buckley ST, Ehrhardt C. (2010) The receptor for advanced glycation end products (RAGE) and the lung. J. Biomed. Biotechnol. 2010:917108.CrossRefGoogle Scholar
  53. 53.
    Lotze MT, DeMarco RA. (2003) Dealing with death: HMGB1 as a novel target for cancer therapy. Curr. Opin. Investig. Drugs. 4:1405–9.PubMedGoogle Scholar
  54. 54.
    Volz HC, Kaya Z, Katus HA, Andrassy M. (2010) The role of HMGB1/RAGE in inflammatory cardiomyopathy. Semin. Thromb. Hemost. 36:185–94.CrossRefGoogle Scholar
  55. 55.
    Nogueira-Machado JA, Volpe CM, Veloso CA, Chaves MM. (2011) HMGB1, TLR and RAGE: a functional tripod that leads to diabetic inflammation. Expert Opin. Ther. Targets. 15:1023–35.CrossRefGoogle Scholar
  56. 56.
    Tikellis C, et al. (2008) Cardiac inflammation associated with a Western diet is mediated via activation of RAGE by AGEs. Am. J. Physiol. Endocrinol. Metab. 295:E323–30.CrossRefGoogle Scholar

Copyright information

© The Author(s) 2012

Open Access This article is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License, which permits any non-commercial use, sharing, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, and provide a link to the Creative Commons license. You do not have permission under this license to share adapted material derived from this article or parts of it.

The images or other third party material in this article are included in the article’s Creative Commons license, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons license and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder.

To view a copy of this license, visit (

Authors and Affiliations

  • Eileen M Bauer
    • 1
  • Richard Shapiro
    • 1
  • Han Zheng
    • 1
  • Ferhaan Ahmad
    • 2
    • 3
    • 4
  • David Ishizawar
    • 2
  • Suzy A Comhair
    • 5
  • Serpil C Erzurum
    • 5
  • Timothy R Billiar
    • 1
  • Philip M Bauer
    • 1
    • 4
    • 6
  1. 1.Department of SurgeryUniversity of Pittsburgh School of MedicinePittsburghUSA
  2. 2.Department of MedicineUniversity of Pittsburgh School of MedicinePittsburghUSA
  3. 3.Department of Human GeneticsUniversity of Pittsburgh School of MedicinePittsburghUSA
  4. 4.Vascular Medicine InstituteUniversity of Pittsburgh School of MedicinePittsburghUSA
  5. 5.Department of PathobiologyLerner Research Institute, and the Respiratory Institute, Cleveland ClinicClevelandUSA
  6. 6.Department of Pharmacology and Chemical BiologyUniversity of Pittsburgh School of MedicinePittsburghUSA

Personalised recommendations