Galangin Suppresses Pro-Inflammatory Gene Expression in Polyinosinic-Polycytidylic Acid-Stimulated Microglial Cells.
	    		
		   		
		   			
		   		
	    	
    	 
    	10.4062/biomolther.2017.173
   		
        
        	
        	
        	
        		- Author:
	        		
		        		
		        		
			        		Min Ji CHOI
			        		
			        		
			        		
			        			1
			        			
			        		
			        		
			        		
			        		
			        		;
		        		
		        		
		        		
			        		Jin Sun PARK
			        		
			        		;
		        		
		        		
		        		
			        		Jung Eun PARK
			        		
			        		;
		        		
		        		
		        		
			        		Han Su KIM
			        		
			        		;
		        		
		        		
		        		
			        		Hee Sun KIM
			        		
			        		
		        		
		        		
		        		
		        		
		        			
			        		
			        		Author Information
			        		
		        		
		        		
			        		
			        		
			        			1. Department of Molecular Medicine, Tissue Injury Defense Research Center, School of Medicine, Ewha Womans University, Seoul 07985, Republic of Korea. hskimp@ewha.ac.kr
			        		
		        		
	        		
        		 
        	
        	
        	
        		- Publication Type:Original Article
 
        	
        	
        		- Keywords:
        			
	        			
	        				
	        				
			        		
				        		Galangin;
			        		
			        		
			        		
				        		Poly(I:C);
			        		
			        		
			        		
				        		Microglia;
			        		
			        		
			        		
				        		PI3K/Akt;
			        		
			        		
			        		
				        		NF-κB;
			        		
			        		
			        		
				        		PPAR-γ signaling
			        		
			        		
	        			
        			
        		
 
        	
            
            	- MeSH:
            	
	        			
	        				
	        				
				        		
					        		Alpinia;
				        		
			        		
				        		
					        		Animals;
				        		
			        		
				        		
					        		Brain;
				        		
			        		
				        		
					        		Cytokines;
				        		
			        		
				        		
					        		Gene Expression*;
				        		
			        		
				        		
					        		Hand;
				        		
			        		
				        		
					        		Honey;
				        		
			        		
				        		
					        		In Vitro Techniques;
				        		
			        		
				        		
					        		Interleukin-10;
				        		
			        		
				        		
					        		Interleukin-6;
				        		
			        		
				        		
					        		Interleukins;
				        		
			        		
				        		
					        		Mice;
				        		
			        		
				        		
					        		Microglia;
				        		
			        		
				        		
					        		Negotiating;
				        		
			        		
				        		
					        		Nitric Oxide;
				        		
			        		
				        		
					        		Peroxisomes;
				        		
			        		
				        		
					        		Phosphorylation;
				        		
			        		
				        		
					        		Phosphotransferases;
				        		
			        		
				        		
					        		Plants, Medicinal;
				        		
			        		
				        		
					        		Poly I-C;
				        		
			        		
				        		
					        		Reactive Oxygen Species;
				        		
			        		
				        		
					        		Tumor Necrosis Factor-alpha;
				        		
			        		
				        		
					        		Up-Regulation
				        		
			        		
	        			
	        			
            	
            	
 
            
            
            	- From:Biomolecules & Therapeutics
	            		
	            		 2017;25(6):641-647
	            	
            	
 
            
            
            	- CountryRepublic of Korea
 
            
            
            	- Language:English
 
            
            
            	- 
		        	Abstract:
			       	
			       		
				        
				        	Galangin (3,5,7-trihydroxyflavone) is a polyphenolic compound abundant in honey and medicinal herbs, such as Alpinia officinarum. In this study, we investigated the anti-inflammatory effects of galangin under in vitro and in vivo neuroinflammatory conditions caused by polyinosinic-polycytidylic acid (poly(I:C)), a viral mimic dsRNA analog. Galangin suppressed the production of nitric oxide, reactive oxygen species, and pro-inflammatory cytokines in poly(I:C)-stimulated BV2 microglia. On the other hand, galangin enhanced anti-inflammatory interleukin (IL)-10 production. Galangin also suppressed the expression of pro-inflammatory markers in poly(I:C)-injected mouse brains. Further mechanistic studies showed that galangin inhibited poly(I:C)-induced nuclear factor (NF)-κB activity and phosphorylation of Akt without affecting MAP kinases. Interestingly, galangin increased the expression and transcriptional activity of peroxisome proliferator-activated receptor (PPAR)-γ, known to play an anti-inflammatory role. To investigate whether PPAR-γ is involved in the anti-inflammatory function of galangin, BV2 cells were pre-treated with PPAR-γ antagonist before treatment of galangin. We found that PPAR-γ antagonist significantly blocked galangin-mediated upregulation of IL-10 and attenuated the inhibition of tumor necrosis factor (TNF)-α and IL-6 in poly(I:C)-stimulated microglia. In conclusion, our data suggest that PI3K/Akt, NF-κB, and PPAR-γ play a pivotal role in mediating the anti-inflammatory effects of galangin in poly(I:C)-stimulated microglia.