Effects of diammonium glycyrrhizinate on Toll-like receptor 4 in alveolar epithelial cells induced by paraquat / 中华急诊医学杂志

ABSTRACT

Objective To investigate the effects of diammonium glycyrrhizinate (DG) on Toll-like receptor 4 in rat alveolar epithelial cells induced by paraquat (PQ).Methods Rats in the PR and PDR groups were induced 2 h by RU486 (100 nmol/L).Then rats in the DG and PDR groups were induced 2 h by DG (0.6 mg/mL).Finally,PQ (0.6 mg/mL) were administered and induced 24h in the PQ,DG,PR and PDR groups,while,the NE group was induced 24 h by absolute ethyl alcohol (0.33 μ mol/L),and the NS group was induced 24 h without drugs.MTT assay was used to measure the cell growth and inhibitioneffects of PQ and DG on cells.The ELISA assay was applied to measure the levels of the TLR-4,Myd88,NF-κB P65 and GR.The gene expressions ofTLR-4,Myd88,NF-κB P65 and GR were detected by RT-PCR.Results The survival rate of rat alveolar epithelial cells was decreased by PQ (200,400,600,800,1 000,1 500,2 000 μmol/L),and the IC50 value for 24 h was 927.045 μmol/L.The inhibition rates were (11.74±1.44)％,(18.76±1.30)％,(28.74±0.54)％,(40.30±0.55)％,(51.24±0.76)％,(68.19±1.10)％,(83.16±0.59)％ in the 200,400,600,800,1 000,1 500,2 000 pmol/L PQ treatment groups,respectively.And the inhibition rates were (48.01±1.37)％,(40.68±2.33)％,(32.76±4.11)％,(34.12±4.3)％,(39.22±2.23)％,(51.26±-0.39)％ in the 0.2,0.4,0.6,0.8,1,and 2 mg/mL DG treatment groups,respectively.The levels of TLR4,Myd88,NF-κB P65,and TNF-a in the PQ and PR groups were higher than those in the NS group (all P＜0.01).While,the levels of GR in the PQ and PR groups were lower than that in the NS group (all P＜0.01).And,the levels of TLR4,Myd88,NF-rκB P65,and TNF-α in the DG and PDR groups were lower than those in the PQ group (all P＜0.01).But the levels of GR in the DG and PDR groups were higher than that in the PQ group (all P＜0.01).Conclusions Diammonium Glycyrrhizinate can attenuate the injury of rat alveolar epithelial cells induced by paraquat,can decrease the levels of TLR-4,Myd88,NF-KB and TNF-α,and increase the GR level.