The effect of electromagnetic fields on oxidative DNA damage

Günümüzdeki birçok çalışma, elektromanyetik alanın biyolojik etkilerinin araştırılması üzerinde odaklanmıştırr. Elektromanyetik alanın biyolojik etkilerinin bazı türlerinin gösterilmiş olmasına rağmen, bu etkilerin moleküler mekanizmaları henüz açıklanamamıştır. Bazı epidemiyolojik çalışmalar, 50-60 Hz dolayındaki düşük düzeyli elektromanyetik alana maruz kalmanın yüksek gerilim hatlarına yakın yaşamakta olan çocuklarda veya elektromanyetik alana maruz kalarak çalışanlarda görülen lösemi gibi kanser vakalarını kapsayan hastalıklara ilişkin riski artırdığını öne sürerken, bazı çalışmalar ise elektromanyetik alan maruziyetinin serbest radikal konsantrasyonunu ve serbest radikallerin izlenebilirliğini artırabileceğini ileri sürmüştür. Elektromanyetik alanın radikal çifti rekombinasyonunu etkilediği bilinmektedir ve bu da, hücrelerdeki oksijene dayalı serbest radikal konsantrasyonunu artırabilir. Bu çalışmada, askorbik asit oksidasyonu ile oksidatif stres oluşturulmuş ve 50 Hz, 0.3 mT düzeyindeki elektromanyetik alanın, oksidatif DNA hasarı üzerindeki etkisi araştırılmıştır. Bu çalışmanın sonuçları, oldukça düşük frekanslı elektromanyetik alanın, oksidatif stresin DNA hasarı üzerindeki etkisini artırdığını göstermifl ve önceki araştırmalardan elde edilen, elektromanyetik alanın serbest radikal konsantrasyonu ve yarı ömrü üzerindeki artırıcı etkisine dair düşünceleri desteklemiştir.

Elektromanyetik alanın oksidatif DNA hasarı üzerindeki etkisi

Many recent studies have focused on the investigation of the biological effects of electromagnetic field. Although the several types of biological effects of electromagnetic fields have been shown, the molecular mechanisms of these effects have not been explained yet. Some epidemiological studies have suggested that exposure to ambient, lowlevel 50-60 Hz electromagnetic fields increase risk of disease including cancer such as leukemia among children who live close to power lines or among men whose jobs expose them to electromagnetic field, while others have suggested that electromagnetic fields exposure could increase both the concentration of free radicals and oscillating free radicals. Electromagnetic fields are known to affect radical pair recombination and they may increase the concentration of oxygen free radicals in living cells. In this study, oxidative stress was formed by the oxidation of ascorbic acid and the effect of 50 Hz, 0.3 mT electromagnetic fields on the oxidative DNA damage has been investigated. The results of the study showed that extremely low-frequency electromagnetic fields enhanced the effect of oxidative stress on DNA damage and supported the idea obtained from the previous studies on an increasing effect of electromagnetic fields on the concentration and the life-time of free radicals.

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