Direct co-culture with human neural stem cells suppresses hemolysate-induced inflammation in RAW 264.7 macrophages through the extracellular signal-regulated kinase pathway
	    		
		   		
		   			
		   		
	    	
    	- Author:
	        		
		        		
		        		
			        		Tae Jung KIM
			        		
			        		
			        		
			        			1
			        			
			        		
			        		
			        		
			        		
			        		;
		        		
		        		
		        		
			        		Jing SUN
			        		
			        		;
		        		
		        		
		        		
			        		Lami KANG
			        		
			        		;
		        		
		        		
		        		
			        		Young-Ju KIM
			        		
			        		;
		        		
		        		
		        		
			        		Sang-Bae KO
			        		
			        		;
		        		
		        		
		        		
			        		Byung-Woo YOON
			        		
			        		
		        		
		        		
		        		
			        		
			        		Author Information
			        		
 - Publication Type:Original Article
 - From: Journal of Neurocritical Care 2024;17(2):49-56
 - CountryRepublic of Korea
 - Language:English
 - 
		        	Abstract:
			       	
			       		
				        
				        	 Background:Inflammation following stroke is associated with poor outcomes, and the anti-inflammatory effects of neural stem cells (NSCs) have been reported. However, the direct immunomodulatory effects of NSCs in hemorrhagic stroke remain unclear. In the present study, we investigated the anti-inflammatory mechanism of direct co-culture with NSCs on RAW 264.7 cells stimulated by hemolysate. 
				        	
Methods:RAW 264.7 cells were stimulated with the hemolysate for 4 hours to induce hemorrhagic inflammation in vitro. Regarding direct co-culture, RAW 264.7 cells were cultured with HB1.F3 cells for 24 hours in normal medium and stimulated with hemolysate for 4 hours. Inflammatory cell signaling molecules, including cycloxygenase-2 (COX-2), interleukin-1β (IL-1β), and extracellular signal-regulated kinase (ERK), as well as tumor necrosis factor-α (TNF-α), were evaluated.
Results:After stimulation with the hemolysate, levels of the inflammatory markers COX-2, IL-1β, and TNF-α were increased in RAW264.7 cells. Inflammatory marker production was reduced in the group subjected to direct co-culture with HB1.F3 in comparison to that in the RAW264.7 group stimulated by the hemolysate. In addition, direct co-culture with HB1.F3 significantly suppressed the phosphorylation of ERK 1/2 in hemolysate-stimulated RAW 264.7 cells. Moreover, treatment of the ERK inhibitor (U0126) suppressed the expression levels of inflammatory markers in hemolysate-stimulated RAW246.7 cells.
Conclusion:These results demonstrate that direct co-culture with HB1.F3 suppresses inflammation by attenuating the ERK pathway. These findings suggest that direct NSC treatment modulates the inflammatory response in hemorrhagic stroke. 
            