The Protective Effects Of Glutamine In Human Bronchial Epithelial Cells Stimulated By Lipopolysaccharide Administration

Objective: To investigate the protective effects of glutamine in human bronchial epithelial cells stimulated by lipopolysaccharide administration, and the expressions of heat shock protein 70 and toll-like receptor 4.Methods: Cultured the human bronchial epithelial cells (16HBE) in vitro, and then divided them into five groups: control group, LPS group (1μg/ml), 0.5mmol/LGln +1μg/ml LPS group,10mmol/LGln +1μg/ml LPS group, 1μg/ml LPS +10mmol/LGln group. The last group added glutamine and LPS at once when the other four groups added glutamine eight hours in advanced the stimulation of LPS. All these groups contained five holes respectively, and LPS stimulated for 24 hours totally. The cell viability of 16HBE was examined by MTT assay through testing their OD values at 490nm wavelength by enzyme linked immunosorbent. Real-time PCR was used to detect the mRNA of HSP70 and TLR-4 for understanding the changes of their expressions.Results:The results of MTT cell viability test:①Compared with the control group, we found that the survival rate of 16HBE in LPS alone group was significantly lower(p<0.05).②Compared with the LPS group, the group added 10mM Gln before the stimulation was the cell showed protective effects, the survival rate significantly improved (p<0.05).③Compared with the 0.5mM Gln group, the survival rate of high concentration group, 10mM Gln +LPS, increased significantly (p<0.05).④The group added 10mmol/L Gln in advanced which could improved the rate obviously, compared with the group of LPS+10mM Gln.The results of Real-time PCR:①Compared with the LPS group, the mRNA expressions of HSP70 increased, but the mRNA expressions of TLR4 decreased in the 10mM Gln+ LPS group,And the difference between the two groups was significance (p<0.05).②Meantime, compared with the 0.5mM Gln group, the group which added 10mM Gln was found that the expression of HSP70 mRNA increased, TLR4mRNA decreased as well as (p<0.05).③The difference between the groups added 10mM Gln pretreatment 8 hours and added at the same time was significance (p<0.05).Conclusion: To some extent, glutamine has protective effects in the human bronchial epithelial cells induced by lipopolysaccharide administration, and the protection is closely related with the time and concentration. We speculated that the regulation of HSP70 and TLR4 may be related to the mechanism in this protective effect.