Evaluation of the Effect of Acetyl L-Carnitine on Experimental Cisplatin Ototoxicity and Neurotoxicity

Introduction: Cisplatin (CDDP) is an effective and widely used chemotherapeutic agent for pediatric tumors, and ototoxicity is one of the dose-limiting side effects. Objective: It was the aim of our study to investigate the effect of acetyl L-carnitine (ALCAR) on experimental CDDP ototoxicity by audiologic tests, histomorphologic, immunohistochemical and ultrastructural examinations and to investigate the apoptotic pathways. Materials and Methods: Wistar albino rats (n = 28) were studied. Baseline audiological tests were performed in 4 groups: group 1, control; group 2, ALCAR; group 3, CDDP; group 4, CDDP + ALCAR-administered rats. Control audiological tests were performed on the 3rd day, and then the rats were sacrificed. Ear and brain specimens were examined by transmission electron microscopy, and caspase 3, 8 and 9 activities were investigated. Results: The CDDP-administered rats showed significant auditory brainstem response threshold shifts using all stimuli (clicks, 6-kHz and 8-kHz tone burst) compared with the control groups. The CDDP + ALCAR-administered rats showed significant auditory brainstem response threshold shifts by only click stimuli compared with the control groups. In the brain, spiral ganglion and organ of Corti, ultrastructural damage was prominent in group 3; the number of TUNEL (terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling)-positive cells and caspase 3, 8 and 9 immunostaining cells was significantly high in group 3. Conclusion: ALCAR improves CDDP-induced auditory impairment, and also antioxidative and antiapoptotic properties of ALCAR on CDDP ototoxicity were supported by the findings. Copyright (C) 2011 S. Karger AG, Basel