Biphasic Increase of Pro-inflammatory Cytokines in Mice Lung after Irradiation. |
Yun Jung Choi, Jin Kyung Rho, Won Seok Jang, Seon Joo Lee, Seung Sook Lee, Jae Soo Koh, Jae Yeol Kim, Hye Ryoun Kim, Cheol Hyeon Kim, Jae Cheol Lee |
1Department of Internal Medicine, Korea Cancer Center Hospital, Seoul, Korea. jclee@kcch.re.kr 2Department of Laboratory of Pathology, Korea Cancer Center Hospital, Seoul, Korea. 3Department of Internal Medicine, College of Medicine, Chung-Ang University, Seoul, Korea. |
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Abstract |
BACKGROUND The pathophysiologic mechanisms of radiation-induced lung injury should be elucidated to enhance the therapeutic efficacy of radiotherapy and to manage patients exposed to serious radiation by accident. It has been suggested that pro-inflammatory cytokines play an important role in radiation-induced effect on the lung. This study was aimed to investigate changes in pro-inflammatory cytokines such as TNF-alpha, MIP-2, IL-1beta and HMGB1, a newly recognized inflammatory mediator. METHODS: The chests of BALB/c mice were selectively irradiated with single fraction of 20 Gy and then sacrificed at indicated times. Pathologic changes in the lung were examined after H&E staining. The expression level of pro-inflammatory cytokines was evaluated by ELISA kits in lung homogenate and in serum. RESULTS: Radiation induced inflammatory changes and mild fibrosis in lung. Biphasic increase of TNF-alpha and IL-1beta was found in lung homogenate at 4 hours and at 3 weeks after radiation. The elevation in the second phase tended to be more intense. However, there was no similar change in serum. MIP-2 level was slightly increased in lung homogenate at 4 hours, but not at 3 weeks. HMGB1 was increased at 3 weeks in serum while there was no significant change in lung homogenate. CONCLUSION: Radiation induced a biphasic increase in TNF-alpha and IL-1beta. The effective control of second phase cytokine elevation should contribute to preventing severe lung fibrosis caused by radiation. |
Key Words:
Radiation, Lung injury, Cytokines |
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