Abstract:

To study the preventive and therapeutic effects of licorice flavonoids on nonspecific lung injury in mice, we established the mouse model of acute lung injury by nasal instillation of lipopolysaccharide (LPS). Mice were treated with licorice flavonoids at dosages of 30 mg/kg before or after LPS nasal instillation. At 6, 12, 24 h after LPS nasal instillation, cytokine level detection, pathological examination , the lung wet/dry weight ratio and the activity changes of NF-κB were performed. The results showed that licorice flavonoids displayed significantly anti-inflammatory in the lung tissue by reduce W/D ratios, attenuated inflammatory cell infiltration and suppress TNF-α, IL-6 and IL-1β expression levels. In addition, the treatment effect of licorice flavonoids was better than prophylaxis effect. Licorice flavonoids could also inhibited the degradation of I kappa B and the transfer of NF kappa B to nuclear. Thus licorice flavonoids could inhibited common LPS downstream channel that was NF-κB. Therefore, We suggested that licorice flavonoids effectively attenuate LPS-induced pulmonary inflammation through inhibition of NF kappa B pathway，and treatment effect of licorice flavonoids was better than prophylaxis effect.