Xuebijing protects against lipopolysaccharide-induced lung injury in rabbits

Interleukin (IL)-23 has been identified as a member of the IL-12 cytokine family. It plays an important role in inflammation. To demonstrate the changes of IL-23 in acute lung injury (ALI) and investigate the protective effect of Xuebijing in ALI and the underlying molecular mechanism, ALI was induced by intravenous injection of lipopolysaccharide (LPS, 750 mu g/kg). Japanese white rabbits challenged with or without LPS were treated with Xuebijing at the same time or saline. Before and after administration of LPS, arterial blood gas and lung weight gain were examined. Pathological changes of lung tissue were measured by light microscopy. IL-23 in serum was detected by enzyme-linked immunosorbent assay (ELISA). All animals demonstrated drops in arterial oxygen tension (Pao(2)) and oxygenation index (Pao(2)/Fio(2)) after LPS application, which were significantly reversed by Xuebijing treatment. Administration of Xuebijing reduced lung water gain. Histopathological study also indicated that Xuebijing treatment markedly attenuated lung histopathological changes, alveolar hemorrhage and inflammatory cells infiltration. Furthermore, IL-23 was higher than control group after LPS treatment, which could be blunted by Xuebijing. These findings confirmed significant protection by Xuebijing against LPS-induced lung vascular leak and inflammation and implicated inhibition of IL-23 expression a potential role for Xuebijing in the management of ALI.