Mustafa Kürşat Gökcan1, Selçuk Mülazimoğlu1, Emre Ocak2, Pınar Can3, Murat Çalışkan3, Ömer Beşaltı3, Serpil Dizbay Sak4, Gülşah Kaygusuz4. 1. Department of Otorhinolaryngology, Faculty of Medicine, Ankara University, Ankara, Turkey. 2. Republic of Turkey Ministry of Health, Keçiören Education and Research Hospital, Ankara, Turkey. 3. Department of Surgery, Faculty of Veterinary Medicine, Ankara University, Ankara, Turkey. 4. Department of Pathology, Faculty of Medicine, Ankara University, Ankara, Turkey.
Abstract
BACKGROUND/AIM: As the regeneration capacity of hair cells is limited, inner ear stem cell therapies hold promise. Effects of mouse induced pluripotent stem cells (IPSCs) on Wistar albino rats (WARs) with hearing impairment were investigated. MATERIALS AND METHODS: Thirty-five adult WARs with normal hearing were divided into 4 groups. Excluding the study group (n = 15), the other three groups served as control groups for ototoxicity and IPSC injection models. IPSC injections were performed via cochleostomy after a retroauricular approach. Auditory functions were evaluated with auditory brainstem responses (ABRs) before and after the injections. After a final hearing assessment the WARs were sacrificed and cochleae were extracted to see the biologic behavior of IPSCs in the inner ear by light microscopy and immunohistochemistry. RESULTS: There were no significant differences in the click-ABR thresholds in the study group after IPSC transplantation. The mean hearing threshold in the study group after ototoxic agent injection was 53.2 dB (10-90 dB). There was no significant difference between groups (P > 0.05) and no differentiated stem cells were observed immunohistochemically. CONCLUSION: Transplanted IPSCs did not show a therapeutic effect in this trial. We discuss potential pitfalls and factors affecting the therapeutic effect.
BACKGROUND/AIM: As the regeneration capacity of hair cells is limited, inner ear stem cell therapies hold promise. Effects of mouse induced pluripotent stem cells (IPSCs) on Wistar albino rats (WARs) with hearing impairment were investigated. MATERIALS AND METHODS: Thirty-five adult WARs with normal hearing were divided into 4 groups. Excluding the study group (n = 15), the other three groups served as control groups for ototoxicity and IPSC injection models. IPSC injections were performed via cochleostomy after a retroauricular approach. Auditory functions were evaluated with auditory brainstem responses (ABRs) before and after the injections. After a final hearing assessment the WARs were sacrificed and cochleae were extracted to see the biologic behavior of IPSCs in the inner ear by light microscopy and immunohistochemistry. RESULTS: There were no significant differences in the click-ABR thresholds in the study group after IPSC transplantation. The mean hearing threshold in the study group after ototoxic agent injection was 53.2 dB (10-90 dB). There was no significant difference between groups (P > 0.05) and no differentiated stem cells were observed immunohistochemically. CONCLUSION: Transplanted IPSCs did not show a therapeutic effect in this trial. We discuss potential pitfalls and factors affecting the therapeutic effect.