The disruption and hyperpermeability of bronchial epithelial barrier are closely related to the pathogenesis of asthma. House dust mite (HDM), one of the most important allergens, could increase the airway epithelial permeability. Heat shock protein (Hsp) 90α is also implicated in the lung endothelial barrier dysfunction by disrupting RhoA signaling. However, the effect of extracellular Hsp90α (eHsp90α) on the bronchial epithelial barrier disruption induced by HDM has never been reported.
To investigate the involvement of eHsp90α in the bronchial epithelial barrier disruption induced by HDM, normal human bronchial epithelial cell line 16HBE14o- (16HBE) cells were treated by HDM, human recombinant (hr) Hsp90α and hrHsp90β respectively and pretreated by1G6-D7, a specific anti-secreted Hsp90α monoclonal antibody (mAb). Hsp90α-silencing cells were also constructed. To further evaluate the role of RhoA signaling in this process, cells were pretreated by inhibitors of Rho kinase, GSK429286A and Y27632 2HCl. Transepithelial electrical resistance (TEER) and FITC-dextran flux (FITC-DX) were examined as the epithelial barrier function. Expression and localization of adherens junctional proteins E-cadherin and β-catenin were evaluated by western blotting and immunofluorescence respectively. The level of eHsp90α was investigated by concentration and purification of condition media. RhoA activity was determined by using a Rho G-LISA® RhoA activation assay kitTM biochem kit, and the phosphorylation of myosin light chain (MLC), the downstream signal molecule of RhoA, was assessed by western blotting.
The epithelial barrier disruption and the loss of adherens junctional proteins E-cadherin and β-catenin in cytomembrane were observed in HDM-treated 16HBE cells, paralleled with the increase of eHsp90α secretion. All of which were rescued in Hsp90α-silencing cells or by pretreating 16HBE cells with 1G6-D7. Also, 1G6-D7 suppressed RhoA activity and MLC phosphorylation induced by HDM. Furthermore, inhibitors of Rho kinase prevented and restored the airway barrier disruption. Consistently, it was hrHsp90α instead of hrHsp90β that promoted barrier dysfunction and activated RhoA/MLC signaling in 16HBE cells.
The eHsp90α mediates HDM-induced human bronchial epithelial barrier dysfunction by activating RhoA/MLC signaling, suggesting that eHsp90α is a potential therapeutic target for treatment of asthma.
Li W, Sahu D, Tsen F. Secreted heat shock protein-90 (Hsp90) in wound healing and cancer. Biochim Biophys Acta. 1823;2012:730–41.
Tong W, Luo W. Heat shock proteins mRNA expressions by peripheral blood mononuclear cells in asthma and chronic bronchitis. Chin Med J (Engl). 2000;113:175–7.
Lee MY, Sun KH, Chiang CP, Huang CF, Sun GH, Tsou YC, et al. Nitric oxide suppresses LPS-induced inflammation in a mouse asthma model by attenuating the interaction of IKK and Hsp90. Exp Biol Med (Maywood). 2015;240:498–507. CrossRef
Voss AK, Thomas T, Gruss P. Mice lacking HSP90beta fail to develop a placental labyrinth. Development. 2000;127:1–11. PubMed
Cheng CF, Fan J, Fedesco M, Guan S, Li Y, Bandyopadhyay B, et al. Transforming growth factor alpha (TGFalpha)-stimulated secretion of HSP90alpha: using the receptor LRP-1/CD91 to promote human skin cell migration against a TGFbeta-rich environment during wound healing. Mol Cell Biol. 2008;28:3344–58. CrossRefPubMedPubMedCentral
Bhatia A, O’Brien K, Chen M, Woodley DT, Li W. Keratinocyte-secreted heat shock protein-90alpha: leading wound reepithelialization and closure. Adv Wound Care (New Rochelle). 2016;5:176–84. CrossRef
Chen WS, Chen CC, Chen LL, Lee CC, Huang TS. Secreted heat shock protein 90alpha (HSP90alpha) induces nuclear factor-kappaB-mediated TCF12 protein expression to down-regulate E-cadherin and to enhance colorectal cancer cell migration and invasion. J Biol Chem. 2013;288:9001–10. CrossRefPubMedPubMedCentral
Zou M, Bhatia A, Dong H, Jayaprakash P, Guo J, Sahu D, et al. Evolutionarily conserved dual lysine motif determines the non-chaperone function of secreted Hsp90alpha in tumour progression. Oncogene. 2017;36(15):2160–71.
Zhang R, Dong H, Zhao H, Zhou L, Zou F, Cai S. 1,25-Dihydroxyvitamin D3 targeting VEGF pathway alleviates house dust mite (HDM)-induced airway epithelial barrier dysfunction. Cell Immunol. 2017;312:15–24.
Steelant B, Farre R, Wawrzyniak P, Belmans J, Dekimpe E, Vanheel H, et al. Impaired barrier function in patients with house dust mite-induced allergic rhinitis is accompanied by decreased occludin and zonula occludens-1 expression. J Allergy Clin Immunol. 2016;137:1043–53. e1041-1045. CrossRefPubMed
Dong X, Huang N, Li W, Hu L, Wang X, Wang Y, et al. Systemic reactions to dust mite subcutaneous immunotherapy: a 3-year follow-up study. Allergy, Asthma Immunol Res. 2016;8:421–7. CrossRef
Tsen F, Bhatia A, O’Brien K, Cheng CF, Chen M, Hay N, et al. Extracellular heat shock protein 90 signals through subdomain II and the NPVY motif of LRP-1 receptor to Akt1 and Akt2: a circuit essential for promoting skin cell migration in vitro and wound healing in vivo. Mol Cell Biol. 2013;33:4947–59. CrossRefPubMedPubMedCentral
- Extracellular heat shock protein 90α mediates HDM-induced bronchial epithelial barrier dysfunction by activating RhoA/MLC signaling
- BioMed Central
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