Juglone Attenuates Sepsis-Induced Acute Lung Injury via Suppression of the TLR4/Nf-κb Pathway

Sepsis, with high mortality, induces deleterious organ dysfunction and acute lung injury. Natural compounds show protective effect against sepsis-induced acute lung injury. Juglone, a natural naphthoquinone, demonstrates pharmacological actions as a pro-apoptotic substrate in tumor treatment and anti-inflammation substrate in organ injury. In this study, the influence of juglone on sepsis-induced acute lung injury was investigated. First, a septic mice model was established via cecal ligation and puncture, and then verified via histopathological analysis of lung tissues, the wet/dry mass ratio and myeloperoxidase activity was determined. Cecal ligation and puncture could induce acute lung injury in septic mice, as demonstrated by alveolar damage and increase of wet/dry mass ratio and myeloperoxidase activity. However, intragastric administration juglone attenuated cecal ligation and puncture-induced acute lung injury. Secondly, cecal ligation and puncture-induced increase of inflammatory cells in bronchoalveolar lavage fluid was also alleviated by the administration of juglone. Similarly, the protective effect of juglone against cecal ligation and puncture-induced acute lung injury was accompanied by a reduction of pro-inflammatory factor secretion in bronchoalveolar lavage fluid and lung tissues. Cecal ligation and puncture could activate toll-like receptor 4/nuclear factor-kappa B signaling pathway, and administration of juglone suppressed toll-like receptor 4/nuclear factor-kappa B activation. In conclusion, juglone attenuated cecal ligation and puncture-induced lung damage and inflammatory response through inactivation of toll-like receptor 4/nuclear factor-kappa B, suggesting a potential therapeutic strategy in the treatment of sepsis-induced acute lung injury.