The effects of ulinastatin on advanced radiation-induced lung injury in rats by negatively regulating the EMT process

TANG Ji-ying; CAO Feng-jun; WANG Xuan-bin; CAI Xiao-jun; LI Hong-liang; LIU Ming; CAO Yang; XIANG Long-chao

doi:10.3969/j.issn.1001-9448.2018.08.004

Abstract：Objective To observe the effects of ulinastatin on advanced radiation -induced lung injury in rats and to investigate its possible mechanism .Methods Forty-eight healthy female SD rats were randomly divided into control group, model group and ulinastatin group according to random number table method .Radiation-induced lung in-jury rat models were established with whole -thorax irradiation of 6MV-X-ray by 20 Gy in model group and ulinastatin group.On the first day after irradiation, the rats in the ulinastatin group were treated with ulinastatin (100,000 U/Kg, 1 time/d); in control group and model group were given with the same volume normal saline .After 8 weeks, the lung tis-sues were taken and Masson staining was used to observe the proliferation of collagen fibers in lung tissues .The content of hydroxyproline in rat lung tissue was determined by alkaline method .The expression of TGF-β1 and EMT-related phe-notypes such as E-cadherin, β-catenin, Vimentin, α-SMA and Snail were assessed by qRT -PCR and Western blot. Results The results of Masson staining showed that the content of collagen fibers ulinastatin group was significantly lower than that in model group, so was the content of hydroxyproline (P＜0.05).Compared with model group, the expression of TGF-β1 in ulinaxatin group was significantly lower (P＜0.05), with significantly up-regulation of E-cadherin and β-catenin (P＜0.05) and down-regulation of Vimentin, α-SMA and Snail decreased (P＜0.05).There was no sig-nificant difference in the expression of related genes between ulinastatin group and control group (P＞0.05).Conclusion Ulinastatin can inhibit the occurrence of EMT by interfering with the expression of TGF -β1, delay the changes of lung tissue fibrosis after thoracic radiation injury , and provide a theoretical basis for clinical prevention and treatment of ad- vanced radioactive lung injury .