Evaluation of the Efficacy of Human Dental Pulp Stem Cell Transplantation in Sprague-Dawley Rats with Sensorial Neural Hearing Loss

Visut Rawiwet; Rattanavijit Vijitruth; Chareonsri Thonabulsombat; Kutkao Vongsavan; Hathaitip Sritanaudomchai

doi:10.1055/s-0043-1761190

Evaluation of the Efficacy of Human Dental Pulp Stem Cell Transplantation in Sprague-Dawley Rats with Sensorial Neural Hearing Loss

Eur J Dent. 2023 Oct;17(4):1207-1214. doi: 10.1055/s-0043-1761190. Epub 2023 Jan 30.

Authors

Visut Rawiwet¹, Rattanavijit Vijitruth², Chareonsri Thonabulsombat³, Kutkao Vongsavan⁴, Hathaitip Sritanaudomchai⁵

Affiliations

¹ Central Animal Facility, Faculty of Science, Mahidol University (MUSC-CAF), Bangkok, Thailand.
² Department of Biology, Faculty of Science, Mahidol University, Bangkok, Thailand.
³ Department of Anatomy, Faculty of Science, Mahidol University, Bangkok, Thailand.
⁴ Department of Pediatric Dentistry, Faculty of Dentistry, Mahidol University, Bangkok, Thailand.
⁵ Department of Oral Biology, Faculty of Dentistry, Mahidol University, Bangkok, Thailand.

Abstract

Objectives: The purpose of the present study was to evaluate the efficacy of spiral ganglion neuron (SGN) regeneration after dental pulp stem cell (DPSC) transplantation in a rat sensorineural hearing loss (HL) model.

Materials and methods: Sham or experimental HL was induced in adult Sprague-Dawley rats by cochlear round window surgery. An HL rat model was established with a single 10 mM ouabain intratympanic injection. After 7 days, the rats received DPSCs, stem cells from human exfoliated deciduous teeth (SHED), or culture medium in the sutural area to establish four groups: sham, HL-DPSC, HL-SHED, and HL-medium. Histological analyses were performed at 4, 7, and 10 weeks after transplantation, and the number of SGNs, specific SGN protein expression, and the function of SGNs were evaluated.

Statistical analysis: Data were statistically by MS Excel and SPSS v.15.0. Intergroup level of significance was determined via a one-way analysis of variance and Duncan's multiple range test with 95% confidence intervals.

Results: New SGN formation was observed in the HL-DPSC and HL-SHED rat groups. The number of SGNs was significantly higher in the HL-DPSC and HL-SHED groups than in the HL-medium group over 4 to 10-week survival period. HL-DPSC rats exhibited higher SGN density compared with that in HL-SHED group, which was statistically significant at week 10. The regenerated SGNs expressed cochlear wiring regulator GATA-binding-protein 3. Moreover, the SGNs from the HL-DPSC group also exhibited a higher expression of synaptic vesicle protein and regulated action potential-dependent neurotransmitter release compared with SGNs from the HL-SHED group.

Conclusions: Our findings suggest that DPSCs and SHED repair and regenerate SGNs in rat HL model. Dental pulp stem cells represent a promising treatment strategy for restoring damage to the sensory circuits associated with deafness.

The Author(s). This is an open access article published by Thieme under the terms of the Creative Commons Attribution License, permitting unrestricted use, distribution, and reproduction so long as the original work is properly cited. (https://creativecommons.org/licenses/by/4.0/).