Extracellular baskets in inner hair cells and perineuronal nets in auditory nerves: Changes in noise-induced hearing loss rats

IF 2.5 4区医学 Q3 NEUROSCIENCES

Neuroscience Letters Pub Date : 2025-02-06 DOI:10.1016/j.neulet.2025.138147

So Young Kim , Jong Chan Jeon , Bohyeon Park , Do Eun Kim

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引用次数: 0

Abstract

Background

The extracellular baskets of cochlear inner hair cell (IhC) ribbon synapses have been suggested to regulate synaptic coupling. This study aimed to investigate the expression of components of the extracellular baskets of the IhCs, chondroitin sulfate proteoglycans (CSPGs) and a hyaluronan and proteoglycan link protein 1 (HAPLN1) in the cochlea and auditory nerve. In addition, changes in CSPGs and HAPLN1 in noise-injured cochleae were examined.

Methods

The expression of CSPGs, including aggrecan (ACAN), brevican (BCAN), neurocan (NCAN), and HAPLN1, was evaluated in the cochleae of 2-month-old Sprague–Dawley (SD) rats. The expression of CSPGs and HAPLN1 in cochleae and auditory nerves was compared to that in 3-month-old noise-exposed SD rats during the developmental period. The cochlear immunohistochemistry (IHC) and cochlear whole mount immunofluorescence studies were conducted for ACAN, BCAN, NCAN, and HAPLN1. To examine the large ganglial cells in auditory nerves, IHC was conducted for parvalbumin (PV), glutamate decarboxylase 67 (GAD67), postsynaptic density protein 95 (PSD95), and glial fibrillary acidic protein (GFAP). In situ hybridization was performed for BCAN.

Results

ACAN, BCAN, and HAPLN1 expression was detected in the IhCs and was decreased tendency in noise-injured cochleae. In the spiral ganglial cell (SGC) region, ACAN and NCAN were expressed without the expression of BCAN. In auditory nerves, large ganglionic cells (LGCs) are encased with perineuronal nets (PNNs), which express PV, GAD67, and PSD95. The mRNA expression of BCAN was noted in SGCs and glial cells of auditory nerves.

Conclusions

The extracellular baskets of IhCs revealed the expression of CSPGs and HAPLN1, which was attenuated in noise-exposed cochleae. In auditory nerves, PV-positive LGCs with inhibitory synapses presented PNNs. The protein expression of BCAN was restricted to the extracellular baskets of IhC but not to the SGC region. However, the mRNA expression of BCAN in SGCs was not affected.

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来源期刊

Neuroscience Letters 医学-神经科学

CiteScore

5.20

自引率

0.00%

发文量

408

审稿时长

50 days

期刊介绍： Neuroscience Letters is devoted to the rapid publication of short, high-quality papers of interest to the broad community of neuroscientists. Only papers which will make a significant addition to the literature in the field will be published. Papers in all areas of neuroscience - molecular, cellular, developmental, systems, behavioral and cognitive, as well as computational - will be considered for publication. Submission of laboratory investigations that shed light on disease mechanisms is encouraged. Special Issues, edited by Guest Editors to cover new and rapidly-moving areas, will include invited mini-reviews. Occasional mini-reviews in especially timely areas will be considered for publication, without invitation, outside of Special Issues; these un-solicited mini-reviews can be submitted without invitation but must be of very high quality. Clinical studies will also be published if they provide new information about organization or actions of the nervous system, or provide new insights into the neurobiology of disease. NSL does not publish case reports.