{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,27]],"date-time":"2026-08-27T03:04:48Z","timestamp":1787799888464,"version":"build-2784847793"},"reference-count":55,"publisher":"MDPI AG","issue":"23","license":[{"start":{"date-parts":[[2024,12,3]],"date-time":"2024-12-03T00:00:00Z","timestamp":1733184000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100002428","name":"Austrian Science Fund (FWF)","doi-asserted-by":"publisher","award":["I-4811"],"award-info":[{"award-number":["I-4811"]}],"id":[{"id":"10.13039\/501100002428","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["IJMS"],"abstract":"<jats:p>We determined the relative expression levels of the receptors TrkA, TrkB, TrkC, and p75NTR and ligands BDNF, NT-3, NGF, and NT-4 with RNAseq analysis on fetal human inner ear samples, located TrkB and TrkC proteins, and quantified BDNF with in situ hybridization on histological sections between gestational weeks (GW) 9 to 19. Spiral ganglion neurons (SGNs) and satellite glia appear to be the main source of BDNF and synthesis peaks twice at GW10 and GW15\u2013GW17. Tonotopical gradients of BDNF revert between GW8 and GW15 and follow a maturation and innervation density gradient in SGNs. NT-3\/TrkC follows the same time course of expression as BDNF\/TrkB. Immunostaining reveals that TrkB signaling may act mainly through satellite glia, Schwann cells, and supporting cells of K\u00f6lliker\u2019s organ, while TrkC signaling targets SGNs and pillar cells in humans. The NT-4 expression is upregulated when BDNF\/NT-3 is downregulated, suggesting a balancing effect for sustained TrkB activation during fetal development. The mission of neurotrophins expects nerve fiber guidance, innervation, maturation, and trophic effects. The data shall serve to provide a better understanding of neurotrophic regulation and action in human development and to assess the transferability of neurotrophic regenerative therapy from animal models.<\/jats:p>","DOI":"10.3390\/ijms252313007","type":"journal-article","created":{"date-parts":[[2024,12,3]],"date-time":"2024-12-03T10:52:30Z","timestamp":1733223150000},"page":"13007","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":5,"title":["Expression of Neurotrophins and Its Receptors During Fetal Development in the Human Cochlea"],"prefix":"10.3390","volume":"25","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-7309-9820","authenticated-orcid":false,"given":"Claudia","family":"Steinacher","sequence":"first","affiliation":[{"name":"Department of Otorhinolaryngology, Medical University Innsbruck, 6020 Innsbruck, Austria"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6640-2297","authenticated-orcid":false,"given":"Shin-ya","family":"Nishio","sequence":"additional","affiliation":[{"name":"Department of Hearing Implant Sciences, Shinshu University School of Medicine, Matsumoto 3-1-1 Asahi, Nagano 390-8621, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5068-6122","authenticated-orcid":false,"given":"Shin-ichi","family":"Usami","sequence":"additional","affiliation":[{"name":"Department of Hearing Implant Sciences, Shinshu University School of Medicine, Matsumoto 3-1-1 Asahi, Nagano 390-8621, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9877-3399","authenticated-orcid":false,"given":"Jozsef","family":"Dudas","sequence":"additional","affiliation":[{"name":"Department of Otorhinolaryngology, Medical University Innsbruck, 6020 Innsbruck, Austria"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1754-690X","authenticated-orcid":false,"given":"Dietmar","family":"Rieder","sequence":"additional","affiliation":[{"name":"Institute of Bioinformatics, Medical University Innsbruck, 6020 Innsbruck, Austria"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Helge","family":"Rask-Andersen","sequence":"additional","affiliation":[{"name":"Department of Surgical Sciences, Otorhinolaryngology and Head and Neck Surgery, Uppsala University, 751 85 Uppsala, Sweden"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0006-009X","authenticated-orcid":false,"given":"Berta","family":"Crespo","sequence":"additional","affiliation":[{"name":"UCL Great Ormond Street Institute of Child Health, University College London, London WC1 N1EH, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Nadjeda","family":"Moreno","sequence":"additional","affiliation":[{"name":"UCL Great Ormond Street Institute of Child Health, University College London, London WC1 N1EH, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9706-7396","authenticated-orcid":false,"given":"Marko","family":"Konschake","sequence":"additional","affiliation":[{"name":"Institute of Clinical and Functional Anatomy, Medical University Innsbruck, 6020 Innsbruck, Austria"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Christof","family":"Seifarth","sequence":"additional","affiliation":[{"name":"Institute of Clinical and Functional Anatomy, Medical University Innsbruck, 6020 Innsbruck, Austria"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2900-6866","authenticated-orcid":false,"given":"Rudolf","family":"Glueckert","sequence":"additional","affiliation":[{"name":"Department of Otorhinolaryngology, Medical University Innsbruck, 6020 Innsbruck, Austria"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2024,12,3]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Chatterjee, S., Kraus, P., and Lufkin, T. 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