Publication: The effect of magnesium and vitamin E pre-treatments on irradiation-induced oxidative injury of cardiac and
Abstract
Amaç: Serbest radikal süpürücü moleküller olan magnezyum sülfat ve E vitamininin profilaktik kullanımının radyasyonun tetiklediği kalp ve akciğer hasarının önlenmesinde lipit peroksidasyonu üzerindeki etkileri incelendi. Yöntemler: Sprague-Dawley türü dişi sıçanlar basit rastgele randomizasyon yöntemi kullanılarak fizyolojik tuzlu su uygulanan kontrol (n=4), tek başına radyasyon (IR; n=6), radyasyon+magnezyum (Mg+IR; n=6) ve radyasyon+vitamin E (vit E+IR; n=6) ön-tedavisine göre gruplandırıldı. Fizyolojik tuzlu su, Mg (600 mg/kg/gün) ya da vit E (100 mg/kg/gün) radyasyondan önce 5 gün boyunca intraperitonal olarak uygulandı. Son enjeksiyondan 20 saat sonra radyasyon uygulanacak tüm gruplardaki sıçanlara 6 MV foton enerjisi ile 20 Gy iyonizan radyasyon uygulandı. Yirmi-dört saat sonra alınan kalp ve akciğer dokularında miyeloperoksidaz aktivitesi (MPO), malondiyaldehid (MDA) ve kemolüminesans (KL) yöntemi ile lüminol ve lusigenin düzeylerine bakıldı. Bulgular: Deney grupları arasında kalp ve akciğer dokularının MDA ve KL sonuçları arasında anlamlı bir fark bulunamadı. Ancak, fizyolojik tuzlu su tedavili ışınlama (IR) grubunun kalp ve akciğer MPO aktiviteleri kontrol grubuna göre yüksek bulunurken (hepsi için p<0.05), Mg-ön tedavili ve vitE-ön tedavili IR gruplarında nötrofil infiltrasyonunun azaldığı gözlendi; fakat bu azalma sadece Mg-ön tedavili grupta istatistiksel olarak anlamlı düzeye ulaştı (p<0.05). Sonuç: Magnezyum sülfatın profilaktik kullanımı ışınlamanın erken 24. saatinde kalp ve akciğer dokusuna nötrofil göçünü sınırlandırmıştır. Ancak, serbest radikallerin ve enflamatuvar mediyatörlerin kaynağı olan nötrofilleri sınırlamanın akciğer ve kalp dokularında ışınlamaya bağlı uzun dönemde gelişecek oksidan hasara nasıl etki edeceği henüz açıklanamamıştır.
Objective: The aim of this study was to investigate the effect of pre-treatment with the free radical scavenging molecules, magnesium and vitamin E, on lipid peroxidation to limit radiation-induced heart and lung injury. Methods: Female Sprague-Dawley rats were divided into 4 groups by a simple randomization method as saline-treated control (n=4), salinetreated irradiated (IR; n=6), magnesium sulphate-treated irradiation (IR) (Mg+IR; n=6) and vitamin E-treated IR (vit E+IR; n=6), respectively. The animals were given either saline, Mg (600mg/kg/day) or vit E (100 mg/kg/day) intraperitoneally for five days prior to irradiation. Twelve hours after the fifth injection, animals in irradiation groups were irradiated to 20 Gy using 6 MV photons in linear accelerator. Twenty-four hours later cardiac and lung tissue samples were obtained for determination of myeloperoxidase activity (MPO), malondialdehyde (MDA) levels, and luminol and lucigenin levels measured by chemiluminescence (CL) methods. Results: No significant changes were observed between cardiac and pulmonary MDA and CL results of the experimental groups. However, cardiac and pulmonary MPO activities in the saline-treated IR group were increased as compared to control group (p<0.05 for all), while in the Mg-pretreated and vit E pretreated groups neutrophil infiltration was reduced, reaching to statistical significance only in the Mg-pretreated group (p<0.05). Conclusion: Prophylactic use of magnesium sulfate has limited the infiltration of neutrophils to both the cardiac and pulmonary tissues at the early 24 h of irradiation. However, how limiting neutrophils as the sources of free radicals and inflammatory mediators would alter oxidative stress of heart and lung tissues in the long-term is not clear yet.
Objective: The aim of this study was to investigate the effect of pre-treatment with the free radical scavenging molecules, magnesium and vitamin E, on lipid peroxidation to limit radiation-induced heart and lung injury. Methods: Female Sprague-Dawley rats were divided into 4 groups by a simple randomization method as saline-treated control (n=4), salinetreated irradiated (IR; n=6), magnesium sulphate-treated irradiation (IR) (Mg+IR; n=6) and vitamin E-treated IR (vit E+IR; n=6), respectively. The animals were given either saline, Mg (600mg/kg/day) or vit E (100 mg/kg/day) intraperitoneally for five days prior to irradiation. Twelve hours after the fifth injection, animals in irradiation groups were irradiated to 20 Gy using 6 MV photons in linear accelerator. Twenty-four hours later cardiac and lung tissue samples were obtained for determination of myeloperoxidase activity (MPO), malondialdehyde (MDA) levels, and luminol and lucigenin levels measured by chemiluminescence (CL) methods. Results: No significant changes were observed between cardiac and pulmonary MDA and CL results of the experimental groups. However, cardiac and pulmonary MPO activities in the saline-treated IR group were increased as compared to control group (p<0.05 for all), while in the Mg-pretreated and vit E pretreated groups neutrophil infiltration was reduced, reaching to statistical significance only in the Mg-pretreated group (p<0.05). Conclusion: Prophylactic use of magnesium sulfate has limited the infiltration of neutrophils to both the cardiac and pulmonary tissues at the early 24 h of irradiation. However, how limiting neutrophils as the sources of free radicals and inflammatory mediators would alter oxidative stress of heart and lung tissues in the long-term is not clear yet.