The effects of germacrone on lipopolysaccharide-induced acute lung injury in neonatal rats

Abstract

Germacrone is one of the main bioactive components in the traditional Chinese medicine Rhizoma curcuma and has been shown to possess an anti-inflammatory activity. Our present study aimed to investigate the protective effects of germacrone on lipopolysaccharide (LPS)-induced acute lung injury in neonatal rats. Results showed that germacrone treatment significantly decreased the expression of pro-inflammatory cytokines IL-6 and TNF-α. Meanwhile, the expression of anti-inflammatory mediators TGF-β1 and IL-10 was obviously increased following germacrone administration. The LPS-induced pathological changes in neonatal rats were also attenuated by germacrone treatment. In vitro, MTT and EdU incorporation assay indicated that germacrone administration significantly increased the A549 cell viabilities in a dose-dependent manner. Besides, flow cytometry and TUNEL analysis showed that the cell apoptosis rate was significantly reduced in a concentration-dependent manner after germacrone injection. At the molecular level, we found that germacrone treatment promoted the expression of claudin-4 both in vivo and in vitro as shown by real time PCR and western blot. Collectively, our study demonstrated that germacrone protected neonatal rats against LPS-induced ALI partially by modulation of claudin-4.