title: Sox10 expressing cells in the lateral wall of the aged mouse and human cochlea.
abstract: Age-related hearing loss (presbycusis) is a common human disorder, affecting one in three Americans aged 60 and over. Previous studies have shown that presbyacusis is associated with a loss of non-sensory cells in the cochlear lateral wall. Sox10 is a transcription factor crucial to the development and maintenance of neural crest-derived cells including some non-sensory cell types in the cochlea. Mutations of the Sox10 gene are known to cause various combinations of hearing loss and pigmentation defects in humans. This study investigated the potential relationship between Sox10 gene expression and pathological changes in the cochlear lateral wall of aged CBA/CaJ mice and human temporal bones from older donors. Cochlear tissues prepared from young adult (1-3 month-old) and aged (2-2.5 year-old) mice, and human temporal bone donors were examined using quantitative immunohistochemical analysis and transmission electron microscopy. Cells expressing Sox10 were present in the stria vascularis, outer sulcus and spiral prominence in mouse and human cochleas. The Sox10(+) cell types included marginal and intermediate cells and outer sulcus cells, including those that border the scala media and those extending into root processes (root cells) in the spiral ligament. Quantitative analysis of immunostaining revealed a significant decrease in the number of Sox10(+) marginal cells and outer sulcus cells in aged mice. Electron microscopic evaluation revealed degenerative alterations in the surviving Sox10(+) cells in aged mice. Strial marginal cells in human cochleas from donors aged 87 and older showed only weak immunostaining for Sox10. Decreases in Sox10 expression levels and a loss of Sox10(+) cells in both mouse and human aged ears suggests an important role of Sox10 in the maintenance of structural and functional integrity of the lateral wall. A loss of Sox10(+) cells may also be associated with a decline in the repair capabilities of non-sensory cells in the aged ear.
authors.affiliation: Department of Otolaryngology - Head & Neck Surgery, Beijing Tongren Hospital, Capital Medical University, Beijing, China; Department of Pathology and Laboratory Medicine, Medical University of South Carolina, Charleston, South Carolina, United States of America.
authors.forename: Xinping
authors.initials: X
authors.lastname: Hao
authors.affiliation: Department of Pathology and Laboratory Medicine, Medical University of South Carolina, Charleston, South Carolina, United States of America.
authors.forename: Yazhi
authors.initials: Y
authors.lastname: Xing
authors.affiliation: Department of Otolaryngology - Head & Neck Surgery, Medical University of South Carolina, Charleston, South Carolina, United States of America.
authors.forename: Michael W
authors.initials: MW
authors.lastname: Moore
authors.affiliation: Department of Pathology and Laboratory Medicine, Medical University of South Carolina, Charleston, South Carolina, United States of America; Department of Otolaryngology, Shanghai Yueyang Integrated Medicine Hospital, Shanghai, China.
authors.forename: Jianning
authors.initials: J
authors.lastname: Zhang
authors.affiliation: Department of Otolaryngology - Head & Neck Surgery, Beijing Tongren Hospital, Capital Medical University, Beijing, China.
authors.forename: Demin
authors.initials: D
authors.lastname: Han
authors.affiliation: Department of Pathology and Laboratory Medicine, Medical University of South Carolina, Charleston, South Carolina, United States of America; Department of Otolaryngology - Head & Neck Surgery, Medical University of South Carolina, Charleston, South Carolina, United States of America.
authors.forename: Bradley A
authors.initials: BA
authors.lastname: Schulte
authors.affiliation: Department of Pathology and Laboratory Medicine, Medical University of South Carolina, Charleston, South Carolina, United States of America; Department of Otolaryngology - Head & Neck Surgery, Medical University of South Carolina, Charleston, South Carolina, United States of America.
authors.forename: Judy R
authors.initials: JR
authors.lastname: Dubno
authors.affiliation: Department of Pathology and Laboratory Medicine, Medical University of South Carolina, Charleston, South Carolina, United States of America.
authors.forename: Hainan
authors.initials: H
authors.lastname: Lang
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000375:Aging / Q000378:metabolism*; D000818:Animals; D001309:Auditory Threshold; D024403:Carbonic Anhydrase III / Q000378:metabolism; D003051:Cochlea / Q000166:cytology* / Q000378:metabolism* / Q000648:ultrastructure; D005260:Female; D006801:Humans; D008297:Male; D008808:Mice, Inbred CBA; D008875:Middle Aged; D055757:SOXE Transcription Factors / Q000378:metabolism*; D000254:Sodium-Potassium-Exchanging ATPase / Q000378:metabolism; D055493:Spiral Ligament of Cochlea / Q000378:metabolism; D013316:Stria Vascularis / Q000378:metabolism / Q000648:ultrastructure; D013701:Temporal Bone / Q000378:metabolism; D014019:Tissue Donors
chemical_list: D055757:SOXE Transcription Factors; D024403:Carbonic Anhydrase III; D000254:Sodium-Potassium-Exchanging ATPase