ABSTRACT
Objective To investigate the changes in the expression of cold-inducible RNA-binding protein (CIRBP) in a radiation-induced lung injury model. Methods Thirty male C57BL/6 mice were randomly divided by body weight into control group (no intervention) and model group (single chest X-ray irradiation with a dose of 20 Gy to build a radiation-induced lung injury model). The mice were dissected five weeks after irradiation. Hematoxylin-eosin staining and Masson staining were used to observe the pathological changes of the lung tissue and the deposition of collagen fibers. Immunohistochemistry was used to measure the expression of the inflammatory factors interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α) in the lung tissue. qRT-PCR was used to measure the expression of CIRBP mRNA in the lung tissue. The expression of CIRBP protein in the lung tissue was determined by the immunofluorescence assay and Western blot. Results Compared with the control group, the model group showed significant pulmonary vascular congestion, significant inflammatory cell infiltration, significant thickening of some alveolar septa, significantly increased IL-6 expression [(129.41 ± 5.58) vs (187.22 ± 34.77), t = 3.179, P < 0.05], significantly increased TNF-α expression [(137.52 ± 23.53) vs (187.02 ± 19.16), t = 5.069, P < 0.05], significantly increased CIRBP mRNA expression [(1 ± 0.08) vs (1.97 ± 0.39), t = 3.45, P < 0.05], and significantly increased CIRBP protein expression [(9.32 ± 1.26) vs (14.76 ± 1.61), t = 3.751, P < 0.05], by the immunofluorescence assay; [(1.13 ± 0.17) vs (1.49 ± 0.14), t = 2.819, P < 0.05], by Western blot). Conclusion The expression of CIRBP is significantly increased in the radiation-induced lung injury model, which may be an important pro-inflammatory factor in radiation-induced lung injury.