title: Hair cell regeneration or the expression of related factors that regulate the fate specification of supporting cells in the cochlear ducts of embryonic and posthatch chickens.
abstract: Hair cells in posthatch chickens regenerate spontaneously through mitosis or the transdifferentiation of supporting cells in response to antibiotic injury. However, how embryonic chicken cochleae respond to antibiotic treatment remains unknown. This study is the first to indicate that unlike hair cells in posthatch chickens, the auditory epithelium was free from antibiotic injury (25-250 mg gentamicin/kg) in embryonic chickens, although FITC-conjugated gentamicin actually reached embryonic hair cells. Next, we examined and counted the cells and performed labeling for BrdU, Sox2, Atoh1/Math1, PV or p27(kip1) (triple or double labeling) in the injured cochlea ducts after gentamicin treatment at 2 h (h), 15 h, 24 h, 2 days (d), 3 d and 7 d after BrdU treatment in posthatch chickens. Our results indicated that following gentamicin administration, proliferating cells (BrdU+) were labeled for Atoh1/Math1 in the damaged areas 3d after gentamicin administration, whereas hair cells (PV+) renewed through mitosis (BrdU+) or direct transdifferentiation (BrdU-) were evident only after 5 d of gentamicin administration. In addition, Sox2 expression was up-regulated in triggered supporting cells at an early stage of regeneration, but stopped at the advent of mature hair cells. Our study also indicated that p27(kip1) was expressed in both hair cells and supporting cells but was down-regulated in a subgroup of the supporting cells that gave rise to hair cells. These data and the obtained dynamic changes of the cells labeled for BrdU, Sox2, Atoh1/Math1, PV or p27(kip1) are useful for understanding supporting cell behaviors and their fate specification during hair cell regeneration.
authors.affiliation: Beijing Key Laboratory of Gene Resource and Molecular Development, Beijing Normal University, China.
authors.forename: Lingling
authors.initials: L
authors.lastname: Jiang
authors.affiliation: Beijing Key Laboratory of Gene Resource and Molecular Development, Beijing Normal University, China.
authors.forename: Ran
authors.initials: R
authors.lastname: Jin
authors.affiliation: Department of Otorhinolaryngology, General Hospital of the Second Artillery, PLA, Beijing, China.
authors.forename: Jincao
authors.initials: J
authors.lastname: Xu
authors.affiliation: Department of Otorhinolaryngology, General Hospital of the Second Artillery, PLA, Beijing, China.
authors.forename: Yubin
authors.initials: Y
authors.lastname: Ji
authors.affiliation: Department of Otorhinolaryngology, General Hospital of the Second Artillery, PLA, Beijing, China.
authors.forename: Meiguang
authors.initials: M
authors.lastname: Zhang
authors.affiliation: College of Life Sciences, Hainan Normal University, Haikou, China.
authors.forename: Xuebo
authors.initials: X
authors.lastname: Zhang
authors.affiliation: College of Life Sciences, Hainan Normal University, Haikou, China.
authors.forename: Xinwen
authors.initials: X
authors.lastname: Zhang
authors.affiliation: Department of Otorhinolaryngology, General Hospital of the Second Artillery, PLA, Beijing, China. Electronic address: zhongminghan@yahoo.com.cn.
authors.forename: Zhongming
authors.initials: Z
authors.lastname: Han
authors.affiliation: Beijing Key Laboratory of Gene Resource and Molecular Development, Beijing Normal University, China. Electronic address: sjzeng@bnu.edu.cn.
authors.forename: Shaoju
authors.initials: S
authors.lastname: Zeng
mesh_terms: D000367:Age Factors; D000818:Animals; D000831:Animals, Newborn; D000900:Anti-Bacterial Agents / Q000633:toxicity*; D015415:Biomarkers / Q000378:metabolism; D019070:Cell Lineage / Q000187:drug effects*; D054338:Cell Transdifferentiation / Q000187:drug effects*; D002642:Chick Embryo; D002645:Chickens; D003053:Cochlear Duct / Q000187:drug effects* / Q000196:embryology / Q000378:metabolism / Q000473:pathology; D005455:Fluorescent Antibody Technique; D018507:Gene Expression Regulation, Developmental; D005839:Gentamicins / Q000633:toxicity*; D006198:Hair Cells, Auditory / Q000187:drug effects* / Q000378:metabolism / Q000473:pathology; D007760:Labyrinth Supporting Cells / Q000187:drug effects* / Q000378:metabolism / Q000473:pathology; D008938:Mitosis / Q000187:drug effects; D012038:Regeneration / Q000187:drug effects*; D013997:Time Factors
chemical_list: D000900:Anti-Bacterial Agents; D015415:Biomarkers; D005839:Gentamicins
keywords: Antibiotic injury; Embryonic chicken; Hair cell; Posthatch chicken; Regeneration