Investigation of serum ribeye and prestin amounts in guinea pigs with congenital hearing loss

Background and Aim: Hearing is a complex process that occurs through the transmission of sound waves to the inner ear via the ear structures, where they are converted into neural impulses and conveyed to the cerebral cortex. The electromotility of outer hair cells in the inner ear is a key factor determining the sensitivity of this process. Prestin protein is responsible for the motility of outer hair cells and plays a crucial role in cochlear amplification. On the other hand, ribeye protein, as a major component of ribbon synapses located in inner hair cells, plays an important role in the synaptic transmission of auditory signals. Congenital hearing loss is a type of permanent hearing impairment that is present at birth or manifests within the early years of life, significantly affecting language, cognitive, and social development. Therefore, early diagnosis and intervention are crucial, and there is a need for the development of reliable biomarkers. This study aimed to evaluate the relationship of these proteins with hearing loss by measuring serum prestin and ribeye levels in guinea pigs with experimentally induced congenital hearing loss. Material and Methods: In this study, a total of 20 young-adult Hartley guinea pigs (0–6 months old, weighing 250–650 g) were used, comprising 10 animals in the experimental group and 10 in the control group. The experimental group consisted of guinea pigs with congenital hearing loss, whereas the control group included animals with normal hearing function. The guinea pigs were housed under controlled conditions at 50% humidity and 21 ± 3°C, with a 12-hour light/12-hour dark cycle. All experimental procedures were performed under general anesthesia; sedation was achieved by intramuscular administration of ketamine hydrochloride (50 mg/kg) and xylazine hydrochloride (10 mg/kg). Hearing functions were evaluated using Auditory Brainstem Response (ABR) and Distortion Product Otoacoustic Emissions (DPOAE) tests, and guinea pigs diagnosed with congenital hearing loss were included in the study. Blood samples were collected via intracardiac puncture under anesthesia, and serum Prestin and Ribeye levels were measured using commercial ELISA kits. Results: Serum Prestin levels did not show a significant difference between the experimental and control groups; however, the values were lower in guinea pigs with congenital hearing loss compared to the control group. Similarly, although Ribeye levels were higher in the control group, no statistically significant difference was observed between the groups. Conclusion: The findings revealed that serum Prestin and Ribeye levels in guinea pigs with congenital hearing loss did not show significant changes compared to the control group. This suggests that the use of both proteins as biomarkers in congenital hearing loss may be limited; however, it provides valuable insight into understanding the pathophysiological differences between acquired and congenital hearing loss. Larger-scale studies incorporating multiple biomarkers may help to clarify the roles of these proteins. Keywords: Congenital hearing loss, elisa test, guinea pig, prestin, ribeye Financial Support: