Age-dependent modifications of expression level of VEGF and its receptors in the inner ear.
The mechanisms responsible for age-associated hearing loss are still incompletely characterized. In this study, we used a murine model of age-dependent hearing loss and evaluated whether this condition is associated with vascular modifications of the structures of the inner ear. We used old C57BL/6J mice that are affected by rapid and severe age-related hearing loss, and analyzed the expression pattern of vascular endothelial growth factor (VEGF), a prototypical angiogenic cytokine, and its receptors Flt-1 and Flk-1 in the inner ear. We report for the first time morphological and quantitative data about the expression of these crucial angiogenic molecules in the murine cochlea. We also show that in this animal model, cochlear VEGF expression is significantly reduced as a function of age. Our findings provide new evidence of possible interdependent relationships between aging, VEGF, and presbycusis, suggesting that vascular abnormalities might play a role in aging-associated hearing loss, with potentially important fundamental and clinical implications.
Picciotti
Pasqualina
P
Institute of Otolaryngology, A. Gemelli University Hospital, Università Cattolica del Sacro Cuore School of Medicine, Rome, Italy.
Torsello
Angela
A
Wolf
Federica I
FI
Paludetti
Gaetano
G
Gaetani
Eleonora
E
Pola
Roberto
R
D000375:Aging / Q000502:physiology*; D000818:Animals; D015153:Blotting, Western / Q000379:methods; D003051:Cochlea / Q000737:chemistry*; D016326:Extracellular Matrix Proteins / Q000032:analysis; D005260:Female; D007150:Immunohistochemistry / Q000379:methods; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D023421:Models, Animal; D018995:Myosin Heavy Chains; D024501:Nonmuscle Myosin Type IIB; D011304:Presbycusis / Q000378:metabolism*; D040262:Receptors, Vascular Endothelial Growth Factor / Q000032:analysis*; D014404:Tubulin / Q000032:analysis; D042461:Vascular Endothelial Growth Factor A / Q000032:analysis*; D040281:Vascular Endothelial Growth Factor Receptor-1; D040301:Vascular Endothelial Growth Factor Receptor-2 / Q000032:analysis
D016326:Extracellular Matrix Proteins; D014404:Tubulin; D042461:Vascular Endothelial Growth Factor A; C501163:Flt1 protein, mouse; D040262:Receptors, Vascular Endothelial Growth Factor; D040281:Vascular Endothelial Growth Factor Receptor-1; D040301:Vascular Endothelial Growth Factor Receptor-2; D024501:Nonmuscle Myosin Type IIB; C103815:nonmuscle myosin type IIB heavy chain; D018995:Myosin Heavy Chains