{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,6]],"date-time":"2026-03-06T06:36:03Z","timestamp":1772778963098,"version":"3.50.1"},"reference-count":37,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2026,2,28]],"date-time":"2026-02-28T00:00:00Z","timestamp":1772236800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/100000005","name":"the Department of Defense","doi-asserted-by":"crossref","award":["RH220046"],"award-info":[{"award-number":["RH220046"]}],"id":[{"id":"10.13039\/100000005","id-type":"DOI","asserted-by":"crossref"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Audiology Research"],"abstract":"<jats:p>Background\/Objectives: Blast-induced hearing loss (BIHL) is a major concern, particularly for military personnel, and is linked to impaired auditory neuron survival and synaptic plasticity. This study investigates the potential of the TrkB agonist 7,8-dihydroxyflavone (7,8-DHF) to reduce the severity of BIHL and promote recovery in a mouse model. Methods: Eight-week-old male C57BL\/6J mice were used. A custom-built, compressed air-driven system utilizing a modified paintball apparatus was employed to deliver controlled unilateral double blasts (~22 psi exposure pressure) to the left ear. The blasts were administered 30 min apart. Immediately following the second blast, mice received either 7,8-DHF (10 mg\/kg) or vehicle (10% DMSO) via intraperitoneal injection. Auditory brainstem responses (ABRs) were measured in both ears at baseline (pre-blast) and at several post-exposure time points. Results: The consecutive blast exposure induced a significant elevation in ABR thresholds, indicative of hearing loss, in both the ipsilateral (exposed) and contralateral (unexposed) ears of vehicle-treated mice. Notably, mice treated with 7,8-DHF demonstrated a marked improvement in hearing recovery compared to the vehicle group. Significant reductions in ABR thresholds were observed in the ipsilateral ear at 4 weeks post-blast (p &lt; 0.0001) and in the contralateral ear as early as 1-week post-blast (p = 0.0236). However, the recovery was partial, with ABR thresholds plateauing after 4 weeks. Conclusions: A controlled blast model demonstrates that systemic administration of the TrkB agonist 7,8-DHF exerts a protective effect, partially restoring auditory function after blast injury. This supports the therapeutic potential of targeting the BDNF-TrkB signaling pathway for managing BIHL.<\/jats:p>","DOI":"10.3390\/audiolres16020036","type":"journal-article","created":{"date-parts":[[2026,3,2]],"date-time":"2026-03-02T14:55:01Z","timestamp":1772463301000},"page":"36","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Therapeutic Assessment of TrkB Agonist in a Unilateral Blast-Induced Hearing Loss Mouse Model"],"prefix":"10.3390","volume":"16","author":[{"given":"Sung Kyun","family":"Kim","sequence":"first","affiliation":[{"name":"Kresge Hearing Research Institute, Department of Otolaryngology-Head and Neck Surgery, University of Michigan, Ann Arbor, MI 48109, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7542-552X","authenticated-orcid":false,"given":"Han-Gyu","family":"Bae","sequence":"additional","affiliation":[{"name":"Kresge Hearing Research Institute, Department of Otolaryngology-Head and Neck Surgery, University of Michigan, Ann Arbor, MI 48109, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0207-8410","authenticated-orcid":false,"given":"Jun Hee","family":"Kim","sequence":"additional","affiliation":[{"name":"Kresge Hearing Research Institute, Department of Otolaryngology-Head and Neck Surgery, University of Michigan, Ann Arbor, MI 48109, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2026,2,28]]},"reference":[{"key":"ref_1","unstructured":"Affairs USDoV (2025). 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