Pirfenidone inhibits the polarization of M2 macrophages by down-regulating IRF4 to reduce the occurrence and development of radiation-induced lung fibrosis
	    		
		   		
		   			
		   		
	    	
    	 
    	10.3760/cma.j.cn113030-20210331-00128
   		
        
        	
        		- VernacularTitle:吡非尼酮下调IRF4抑制M2型巨噬细胞活化减轻放射性肺纤维化机制
 
        	
        	
        	
        		- Author:
	        		
		        		
		        		
			        		Min FANG
			        		
			        		
			        		
			        			1
			        			
			        		
			        		
			        		
			        		
			        		;
		        		
		        		
		        		
			        		Hangjie YING
			        		
			        		;
		        		
		        		
		        		
			        		Qingqing HANG
			        		
			        		;
		        		
		        		
		        		
			        		Yamei CHEN
			        		
			        		;
		        		
		        		
		        		
			        		Ming CHEN
			        		
			        		
		        		
		        		
		        		
		        		
		        			
			        		
			        		Author Information
			        		
		        		
		        		
			        		
			        		
			        			1. 中国科学院大学附属肿瘤医院(浙江省肿瘤医院)放疗科,中国科学院基础医学与肿瘤研究所,杭州 310022
			        		
		        		
	        		
        		 
        	
        	
        	
        	
        		- Keywords:
        			
	        			
	        				
	        				
			        		
				        		Pirfenidone;
			        		
			        		
			        		
				        		Radiation-induced lung fibrosis;
			        		
			        		
			        		
				        		Macrophage;
			        		
			        		
			        		
				        		Interferon regulatory factor 4
			        		
			        		
	        			
        			
        		
 
        	
            
            
            	- From:
	            		
	            			Chinese Journal of Radiation Oncology
	            		
	            		 2022;31(6):562-568
	            	
            	
 
            
            
            	- CountryChina
 
            
            
            	- Language:Chinese
 
            
            
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		        	Abstract:
			       	
			       		
				        
				        	Objective:To explore the preventive and therapeutic effect of pirfenidone (PFD) on radiation-induced lung fibrosis (RILF) and its mechanism.Methods:40 female C57/BL6 mice were randomly divided into 4 groups: negative control group (NC), PFD treatment group (PFD), radiation treatment group (RT) and radiation plus PFD treatment group (RT+ PFD). Mice in RT and RT+ PFD groups received a single whole lung X-ray consisting of a 50 Gy dose of radiation, delivered by small animal radiation research platform (SARRP). PFD at a dose of 300 mg/kg was administered orally 2 h before irradiation for 150 d. HE and Masson staining were used to detect the infiltration of inflammatory cells and the degree of pulmonary fibrosis. Quantitative real-time PCR (qPCR) and Western blotting (WB) were adopted to detect the expression levels of M1/M2 macrophage phenotypic markers. The expression levels of arginase-1(ARG-1), chitinase 3-like protein 3(YM-1) and interferon regulatory factor-4(IRF4) of macrophages stimulated with IL-4 and IL-13 were detected by WB. In addition, immunofluorescence staining was used to detect the expression and translocation of IRF4 in macrophages among different treatment groups.Results:HE and Masson staining showed that PFD could significantly inhibit radiation-induced infiltration of inflammatory cells and fibrosis in lung tissues. The M2 macrophages and expression levels of ARG-1 and YM-1 were down-regulated in the RT+ PFD group. Cell experiments further confirmed that PFD could significantly inhibit the polarization of macrophages to M2 induced by IL-4+ IL-13, which was mainly related to the down-regulation of IRF4.Conclusion:PFD has a preventive and therapeutic effect on RILF by inhibiting IRF4 and reducing the polarization of macrophages to M2.