Aysel ARICIOĞLU, Özlem GÜLBAHAR, Müge AKMANSU, Zerrin TÜRKÖZER

Radyosyonun serum demir, bakır ve protein oksidasyon düzeylerine etkisi

Bir çok hastalığın etyopatogenezinde rol oynadığı düşünülen proteinlerin oksidatif modifikasyonunu analiz etmek amacıyla en sık kullanılan yöntem protein oksidasyon ürünü olan karbonil gruplarının tayinidir. Biz de çalışmamızda, radyasyonun serum üzerindeki etkisini göstermek amacıyla protein oksidasyon ürünü olan karbonil grubu düzeylerini ve “metallerin katalizlediği oksidasyon” (metal-catalyzed oxidation, MCO) sistemleri aracılığıyla protein oksidasyonunu artırdığı bilinen demir (Fe) ve bakır (Cu) düzeylerini araştırmayı amaçladık. Gereç ve Yöntemler: Kobaylara radyasyon ve antioksidan (N-asetilsistein, NAC) uygulamaları sonrasında serum Fe, Cu ve protein oksidasyon düzeyleri analiz edildi. Protein oksidasyon düzeyi Levine metoduna göre, Fe düzeyi otoanalizörde, Cu düzeyi ise atomik absorbsiyon cihazında ölçüldü. Bulgular: Radyasyonun, serum protein karbonil grubu, Fe ve Cu düzeylerinde istatiksel olarak anlamlı artışlara neden olduğu görüldü. Radyasyon öncesinde NAC verilen grupta ise tek başına radyasyon uygulanan gruba oranla oksidatif stresin azaldığı gözlendi. Kobaylara yalnızca NAC verilmesi de parametrelerde azalmaya neden oldu. Sonuç: Sonuç olarak radyasyonun muhtemelen reaktif oksijen türlerinin düzeyini artırarak, ayrıca Fe ve Cu düzeylerini yükseltip metal katalizli oksidasyon yoluyla proteinlerin oksidatif modifikasyonuna yol açtığı, NAC’ın ise radyasyonun oluşturduğu oksidasyona karşı koruyucu bir etkisinin olduğu tespit edildi.

Effect of radiation on the levels of iron, copper and protein oxidation in serum

The method used most commonly to analyze oxidative modification of the proteins playing a role in the etiopathogenesis of various diseases is the determination of carbonyl groups, which are the oxidative modification products. To demonstrate the effect of radiation on serum, we determined carbonyl group levels that are protein oxidation products and iron (Fe) and copper (Cu) levels, which are known to increase the protein oxidation, using metal-catalyzed oxidation (MCO) systems. Materials and Methods: After exposure to radiation and antioxidant (NAC), guinea pigs’ serum Fe, Cu and protein oxidation levels were analyzed. Protein oxidation was determined by the Levine method, Fe levels were measured using an autoanalyzer and Cu levels were determined using an atomic absorption apparatus. Results: Radiation was found to significantly increase the serum carbonyl groups, and Fe and Cu levels. Oxidative stress was observed to decrease in the group given NAC before radiation compared to the group receiving radiation only. Giving only NAC to the guinea pigs led to decreases in parameters. Conclusion: Radiation causes oxidative modification of the proteins by an increase in the levels of reactive oxygen radicals and Fe and Cu levels by creating metal catalysis, and NAC has a protective effect against oxidation due to radiation.

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