Ramazan KOZAN, M.Ömer BOSTANCI, Bülent AYAS, ALİ ASLAN, Faruk BAĞIRICI

Sıçan serebellumunda demir nörotoksisitesine karşı vitamin E'nin koruyucu etkisi

Amaç: Bu çalışmada, intraserebroventriküler olarak verilen demirin, sıçan serebellar Purkinje hücrelerinde oluşturduğu nörotoksisiteye karşı yağda çözülebilen güçlü bir antioksidan olan vitamin E'nin (α-tokoferol) etkisini araştırdık. Gereç ve Yöntem: Sıçanlar, kontrol, demir ve demir+vitamin E grupları olmak üzere üç gruba ayrıldı. Demir ve demir+vitamin E gruplarındaki sıçanlara intraserebroventriküler olarak demir (FeCl36H2O, 200 mM, 2.5 μl) verildi. Demir+vitamin E grubundaki sıçanlara operasyonu takiben on gün süreyle 100 mg/kg/gün dozunda vitamin E intraperitoneal olarak verildi. Onuncu günün sonunda, bütün gruplardaki hayvanlar intrakardiyak yolla perfüze edildikten sonra dekapite edildiler. Beyin dokuları çıkarılarak standart histolojik doku takibi uygulandı. Toplam Purkinje hücre sayıları tarafsız sayım metodu olan stereolojik yöntemle hesaplandı. Bulgular: Ortalama toplam Purkinje hücre sayıları, kontrol grubunda 490584±13286; demir grubunda 331497±10764 ve demir+vitamin E grubunda 412118±15842 olarak bulundu. Demir ve demir+vitamin E grupları karşılaştırıldığında, vitamin E'nin demirin indüklediği Purkinje hücre kaybını %32.4'den %15.9'a düşürdüğü bulundu (p

Protective effect of vitamin E against iron -induced neurotoxicity in the rat cerebellum

Objective: In this study, we investigated the effect of vitamin E (α-tocopherol), a potent fat-soluble antioxidant, against intracerebroventricular-injected iron-induced neurotoxicity on the cerebellar Purkinje cells in rats. Materials and Methods: Rats were divided into three groups: control, iron and iron+vitamin E groups. Rats in the iron and iron+vitamin E groups received intracerebroventricular iron (FeCl36H2O, 200 mM, 2.5 μl), while those in iron+vitamin E groups were intraperitoneally injected with vitamin E (100 mg/kg/day) once a day after the operation for 10 days. After 10 days, all rats were perfused intracardially and then sacrificed. Brain tissues were removed and standard histological techniques were performed. The total numbers of Purkinje cells were estimated using unbiased stereological techniques. Results: Means of the total numbers of Purkinje cells in the cerebellum were estimated as 490584±13286, 331497±10764, 412118±15842 in the control, iron and iron+vitamin E groups, respectively. Comparison between iron and iron+vitamin E groups revealed that vitamin E significantly attenuates the iron-induced neuron loss from 32.4% to 15.9% (P < 0.01). Conclusion: Findings of the present study show that α-tocopherol considerably reverses iron-induced Purkinje cell loss in cerebellum. It is thought that this effect may be due to the scavenging activity of vitamin E on free radicals.

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