Perivascular macrophage-like melanocyte responsiveness to acoustic trauma--a salient feature of strial barrier associated hearing loss
2013 (English)In: The FASEB Journal, ISSN 0892-6638, E-ISSN 1530-6860, Vol. 27, no 9, 3730-3740 p.Article in journal (Refereed) Published
Tissue perivascular resident macrophages (PVM/Ms), a hybrid cell type with characteristics of both macrophages and melanocytes, are critical for establishing and maintaining the endocochlear potential (EP) required for hearing. The PVM/Ms modulate expression of tight- and adherens-junction proteins in the endothelial barrier of the stria vascularis (intrastrial fluid-blood barrier) through secretion of a signaling molecule, pigment epithelium growth factor (PEDF). Here, we identify a significant link between abnormalities in PVM/Ms and endothelial barrier breakdown from acoustic trauma to the mouse ear. We find that acoustic trauma causes activation of PVM/Ms and physical detachment from capillary walls. Concurrent with the detachment, we find loosened tight junctions between endothelial cells and decreased production of tight- and adherens-junction protein, resulting in leakage of serum proteins from the damaged barrier. A key factor in the intrastrial fluid-blood barrier hyperpermeability exhibited in the mice is down-regulation of PVM/M modulated PEDF production. We demonstrate that delivery of PEDF to the damaged ear ameliorates hearing loss by restoring intrastrial fluid-blood barrier integrity. PEDF up-regulates expression of tight junction-associated proteins (ZO-1 and VE-cadherin) and PVM/M stabilizing neural cell adhesion molecule (NCAM-120). These studies point to the critical role PVM/Ms play in regulating intrastrial fluid-blood barrier integrity in healthy and noise-damaged ears.
Place, publisher, year, edition, pages
Federation of American Societies for Experimental Biology , 2013. Vol. 27, no 9, 3730-3740 p.
mouse cochlea endothelial cell instrastrial fluidblood barrier paracellular permeability acoustic trauma
IdentifiersURN: urn:nbn:se:liu:diva-101044DOI: 10.1096/fj.13-232892PubMedID: 23729595OAI: oai:DiVA.org:liu-101044DiVA: diva2:665176