Anatomic, physiologic, and proteomic consequences of repeated microneedle-mediated perforations of the round window membrane.
Hear Res
; 432: 108739, 2023 05.
Article
em En
| MEDLINE
| ID: mdl-36966687
ABSTRACT
BACKGROUND:
We have developed 3D-printed microneedle technology for diagnostic aspiration of perilymph and intracochlear delivery of therapeutic agents. Single microneedle-mediated round window membrane (RWM) perforation does not cause hearing loss, heals within 48-72 h, and yields sufficient perilymph for proteomic analysis. In this study, we investigate the anatomic, physiologic, and proteomic consequences of repeated microneedle-mediated perforations of the same RWM at different timepoints.METHODS:
100-µm-diameter hollow microneedles were fabricated using two-photon polymerization (2PP) lithography. The tympanic bullae of Hartley guinea pigs (n = 8) were opened with adequate exposure of the RWM. Distortion product otoacoustic emissions (DPOAE) and compound action potential (CAP) were recorded to assess hearing. The hollow microneedle was introduced into the bulla and the RWM was perforated; 1 µL of perilymph was aspirated from the cochlea over the course of 45 s. 72 h later, the above procedure was repeated with aspiration of an additional 1 µL of perilymph. 72 h after the second perforation, RWMs were harvested for confocal imaging. Perilymph proteomic analysis was completed using liquid chromatography-tandem mass spectrometry (LC-MS/MS).RESULTS:
Two perforations and aspirations were performed in 8 guinea pigs. In six, CAP, DPOAE, and proteomic analysis were obtained; in one, only CAP and DPOAE results were obtained; and in one, only proteomics results were obtained. Hearing tests demonstrated mild hearing loss at 1-4 kHz and 28 kHz, most consistent with conductive hearing loss. Confocal microscopy demonstrated complete healing of all perforations with full reconstitution of the RWM. Perilymph proteomic analysis identified 1855 proteins across 14 samples. The inner ear protein cochlin was observed in all samples, indicating successful aspiration of perilymph. Non-adjusted paired t-tests with p < 0.01 revealed significant changes in 13 of 1855 identified proteins (0.7%) between the first and second aspirations.CONCLUSIONS:
We demonstrate that repeated microneedle perforation of the RWM is feasible, allows for complete healing of the RWM, and minimally changes the proteomic expression profile. Thus, microneedle-mediated repeated aspirations in a single animal can be used to monitor the response to inner ear treatments over time.Palavras-chave
Texto completo:
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Bases de dados:
MEDLINE
Assunto principal:
Proteômica
/
Perda Auditiva
Limite:
Animals
Idioma:
En
Revista:
Hear Res
Ano de publicação:
2023
Tipo de documento:
Article
País de afiliação:
Estados Unidos