title: Is there a relationship between brain-derived neurotrophic factor for driving neuronal auditory circuits with onset of auditory function and the changes following cochlear injury or during aging?
abstract: Brain-derived neurotrophic factor, BDNF, is one of the most important neurotrophic factors acting in the peripheral and central nervous system. In the auditory system its function was initially defined by using constitutive knockout mouse mutants and shown to be essential for survival of neurons and afferent innervation of hair cells in the peripheral auditory system. Further examination of BDNF null mutants also revealed a more complex requirement during re-innervation processes involving the efferent system of the cochlea. Using adult mouse mutants defective in BDNF signaling, it could be shown that a tonotopical gradient of BDNF expression within cochlear neurons is required for maintenance of a specific spatial innervation pattern of outer hair cells and inner hair cells. Additionally, BDNF is required for maintenance of voltage-gated potassium channels (KV) in cochlear neurons, which may form part of a maturation step within the ascending auditory pathway with onset of hearing and might be essential for cortical acuity of sound-processing and experience-dependent plasticity. A presumptive harmful role of BDNF during acoustic trauma and consequences of a loss of cochlear BDNF during aging are discussed in the context of a partial reversion of this maturation step. We compare the potentially beneficial and harmful roles of BDNF for the mature auditory system with those BDNF functions known in other sensory circuits, such as the vestibular, visual, olfactory, or somatosensory system.
authors: Instituto de Biología y Genética Molecular, Universidad de Valladolid y Consejo Superior de Investigaciones Científicas, E-47003 Valladolid, Spain. Electronic address: schimman@ibgm.uva.es.
authors: T
authors: T
authors: Schimmang
authors: Instituto de Biología y Genética Molecular, Universidad de Valladolid y Consejo Superior de Investigaciones Científicas, E-47003 Valladolid, Spain.
authors: B
authors: B
authors: Durán Alonso
authors: University of Tübingen, Department of Otolaryngology, Head and Neck Surgery, Tübingen Hearing Research Center (THRC), Molecular Physiology of Hearing, Elfriede-Aulhorn-Straße 5, 72076 Tübingen, Germany.
authors: U
authors: U
authors: Zimmermann
authors: University of Tübingen, Department of Otolaryngology, Head and Neck Surgery, Tübingen Hearing Research Center (THRC), Molecular Physiology of Hearing, Elfriede-Aulhorn-Straße 5, 72076 Tübingen, Germany.
authors: M
authors: M
authors: Knipper
mesh_terms: D000375:Aging; D000818:Animals; D001306:Auditory Pathways / Q000473:pathology*; D019208:Brain-Derived Neurotrophic Factor / Q000378:metabolism*; D015834:Cochlear Diseases / Q000473:pathology* / Q000503:physiopathology*; D006309:Hearing; D006801:Humans; D009415:Nerve Net / Q000473:pathology*; D011984:Sensory Receptor Cells / Q000378:metabolism
chemical_list: D019208:Brain-Derived Neurotrophic Factor
keywords: BDNF; K(V)3.1; homeostatic adaptation; injury; sensory system