Melatonin reduces X-ray radiation-induced lung injury in mice by modulating oxidative stress and cytokine expression

• Published in: International journal of radiation biology Vol. 89; no. 2; pp. 97 - 105
• Main Authors: Jang, Seong Soon, Kim, Hyeong Geug, Lee, Jin Seok, Han, Jong Min, Park, Hye Jung, Huh, Gil Ja, Son, Chang Gue
• Format: Journal Article
• Language: English
• Published: England Informa Healthcare 01.02.2013; Taylor & Francis
• Subjects: Animals; Base Sequence; Catalase - metabolism; Cytokines - genetics; Cytokines - metabolism; Female; Gene Expression - drug effects; Gene Expression - radiation effects; Glutathione - metabolism; Immunohistochemistry; Inflammation Mediators - metabolism; Interleukin-1beta - genetics; Interleukin-6 - genetics; lung injury; Lung Injury - etiology; Lung Injury - metabolism; Lung Injury - pathology; Lung Injury - prevention & control; Malondialdehyde - metabolism; melatonin; Melatonin - pharmacology; Mice; Mice, Inbred C57BL; oxidative stress; Oxidative Stress - drug effects; Oxidative Stress - radiation effects; Radiation; Radiation Injuries, Experimental - etiology; Radiation Injuries, Experimental - metabolism; Radiation Injuries, Experimental - pathology; Radiation Injuries, Experimental - prevention & control; RNA, Messenger - genetics; RNA, Messenger - metabolism; Space life sciences; Superoxide Dismutase - metabolism; TGF-β1; TNF-α; Transforming Growth Factor beta1 - genetics; Transforming Growth Factor beta1 - metabolism; Tumor Necrosis Factor-alpha - genetics
• ISSN: 0955-3002; 1362-3095
• DOI: 10.3109/09553002.2013.734943

Abstract Purpose: The modification of radiation-induced lung injuries by melatonin was studied by measuring changes in oxidative stress, cytokine expression and histopathology in the lung tissue of mice following irradiation. Materials and methods: The thoraces of C57BL/6 mice were exposed to a single X-ray radiation dose of 12 Gy with or without 200 mg/kg of melatonin pretreatment. The level and localization of transforming growth factor (TGF)-β1 protein were measured using an enzyme-linked immunosorbent assay (ELISA) method and immunohistochemical staining, respectively. Real-time quantitative polymerase chain reaction (PCR) was established to evaluate the relative mRNA expression levels of TGF-β1, tumor necrosis factor (TNF)-α, interleukin (IL)-1β and IL-6. Results: Malondialdehyde (MDA) levels increased after irradiation and then significantly reduced (1.9-fold) under melatonin treatment. Changes in superoxide dismutase (SOD) and catalase activities, as well as glutathione (GSH) levels, after irradiation were significantly reduced by melatonin, including a notable 5.4-fold difference in catalase activity. We observed increased expression of TGF-β1 and TNF-α after irradiation and a significant reduction in the elevation of their expression by melatonin treatment. Furthermore, irradiation-induced histopathologic alterations were obviously abated in the melatonin-pretreated mice. Conclusions: The present results suggest that melatonin reduces radiation-induced lung injury via a significant reduction of oxidative stress and of the production of cytokines, such as TGF-β1 and TNF-α, the production of which increased following lung irradiation.