Objective: Cisplatin is a platinum-based compound used to treat various cancers; however, its severe side effects, such as ototoxicity, limit its clinical use. Ototoxicity can lead to permanent damage, particularly affecting the organ of Corti. This study aimed to histopathologically evaluate the protective effect of betaine, known for its antioxidant and antiinflammatory properties, against cisplatin-induced ototoxicity. Material and Methods: Forty female Wistar albino rats were used with the approval of the Erciyes University Animal Experiments Local Ethics Committee. The rats were randomly assigned to 4 groups (n=10): Sham, Betaine, Cisplatin, and Cisplatin+Betaine. Betaine hydrochloride (250 mg/kg/day) was administered orally once daily for 30 days, while cisplatin (8 mg/kg/week) was administered intraperitoneally once weekly for 4 weeks. Cochlear tissues were collected, fixed, and processed for histopathological evaluation. Results: Cisplatin-induced ototoxicity led to structural deformities in the cochlea, particularly in the organ of Corti at the basal turn. In the Cisplatin+ Betaine group, the organ of Corti exhibited a more preserved structure, with maintained integrity of the stria vascularis and tectorial membrane. Statistically, the Cisplatin group showed significantly reduced stria vascularis and basilar membrane thickness, tectorial membrane length, and inner and outer hair height. In the Cisplatin+Betaine group, these parameters improved, with a significant increase observed in tectorial membrane length across all cochlear turns and outer hair cell height in the apical turn. Conclusion: This study demonstrates the protective role of betaine against cisplatin-induced ototoxicity. While the findings are promising for ototoxicity prophylaxis, further studies are warranted.

Amaç: Sisplatin, birçok kanserin tedavisinde kullanılan bir platin bazlı bileşiktir; ancak ototoksisite gibi ciddi yan etkileri tedavi kısıtlılığı oluşturmaktır. Ototoksisite, özellikle korti organını kalıcı olarak etkileyebilir. Bu çalışmada, antioksidan ve antiinflamatuar özelliklere sahip olduğu bilinen betainin, sisplatine bağlı ototoksisiteye karşı koruyucu etkisi histopatolojik olarak incelenmesi amaçlanmıştır. Gereç ve Yöntemler: Çalışmada, Erciyes Üniversitesi Hayvan Deneyleri Yerel Etik Kurul onayı doğrultusunda 40 adet Wistar albino dişi sıçan kullanıldı. Sıçanlar rastgele 4 eşit gruba (n=10) ayrıldı: Kontrol, Betain, Sisplatin ve Sisplatin+Betain. Deneyler sırasında sıçanlara betain hydrochloride (250 mg/kg/d) 30 gün boyunca (günde 1 kez) oral yolla ve sisplatin (8 mg/kg/d) 4 hafta (haftada 1 kez) intraperitoneal olarak uygulandı. Koklear dokuları toplandı, fiksasyon yapıldı ve histopatolojik değerlendirme yapıldı. Bulgular: Sisplatin ototoksisitesine bağlı olarak kokleanın, özellikle de bazal dönüşte yer alan korti organında deformasyonların meydana geldiği belirlendi. Sisplatin+Betain grubunda ise korti organının daha düzenli bir yapıya sahip olduğu, stria vaskülaris ile tektorial membranın bütünlüğünün korunduğu gözlendi. İstatistiksel sonuçlar da; sisplatin grubunda, stria vaskülaris ve baziler membran kalınlığı, tektorial memebran uzunluğu, dış ve iç saçlı hücre uzunluklarının anlamlı olarak azaldığı görüldü. Sisplatin+Betain grubunda ise artış meydana geldiği ancak bu artışın sadece kokleanın tüm dönüşlerindeki tektorial membran uzunluğunda ve kokleanın apeks dönüşündeki dış saçlı hücre uzunluğunda anlamlı olduğu tespit edildi. Sonuç: Bu çalışma, betainin sisplatin kaynaklı ototoksisiteye karşı koruyucu rolünü ortaya koymaktadır. Bulgular ototoksisite profilaksisi için umut verici olsa da, daha ileri çalışmalara ihtiyaç duyulmaktadır.

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