Utilizing prestin as a predictive marker for the early detection of outer hair cell damage.

ABSTRACT

PURPOSE: To evaluate prestin as a biomarker for the identification of early ototoxicity. MATERIALS AND METHODS: Rats (n = 47) were randomly assigned to five groups low-dose (LAG) or high-dose (HAG) amikacin (200 and 600 mg/kg/day, respectively, for 10 days), low-dose (LCIS)or high-dose (HCIS) cisplatin (single doses of 5 and 15 mg/kg, respectively, for 3 days), and control (n = 8). At the end of the experiment, measurement of distortion product-evoked otoacoustic emissions (DPOAE) were performed to evaluate hearing, then blood samples and both ear tissues were collected under anesthesia. Prestin levels were determined by ELISA. Cochlear damage was evaluated histologically using a 4-point scoring system. RESULTS: The mean serum prestin levels were 377.0 ±â€¯135.3, 411.3 ±â€¯73.1, 512.6 ±â€¯106.0, 455.0 ±â€¯74.2 and 555.3 ±â€¯47.9 pg/ml for control, LCIS, HCIS, LAG and HAG groups, respectively. There was significant difference between prestin levels of Control-LCIS-HCIS groups (p = 0.031) and prestin levels of Control-LAG-HAG groups (p = 0.003). There were also significant differences in prestin levels between the low- and high-dose cisplatin and amikacin groups (p = 0.028 and p = 0.011, respectively). Each group had significantly lower DPOAE results at 4, 6 and 8 kHz than control groups (p < 0.001). The LAG, HAG, LCIS and HCIS groups had significantly higher cochlear damage scores than the control group (p < 0.05). CONCLUSIONS: Higher doses of cisplatin and amikacin were associated with the greatest increases in serum prestin level and cochlear damage score. The results of this study suggest that prestin is a promising early indicator of cochlear damage.