Immunoregulatory effect of Dachengqi decoction on endotoxic ARDS in rats

AIM: To investigate the effect of Dachengqi decoction (DD) on the acute respiratory distress syndrome (ARDS) in rat model induced by endotoxin “two-hit”. METHODS: 48 healthy male Wistar rats were randomly divided into 4 groups: control group, ARDS model group, ARDS+DD treatment group and ARDS+dexamethasone treatment group (12 in each group). E. coli lipopolysaccharide (LPS) “two-hit” induced ARDS model in rats was established. The arterial blood gas analysis, lung wet/dry weight (W/D) ratio and lung tissue pathology observation and scoring were measured to evaluate the pharmacological effects of DD on ARDS. The levels of TNF-α, IL-1 and IL-10 were determined by ELISA to explore the immune regulatory mechanism of DD. RESULTS: (1) Treatment with DD significantly improved blood pressure in rats, increased oxygen saturation, decreased lung wet/dry weight ratio and lung injury score, relieved pulmonary edema and the inflammatory responses. (2) DD suppressed the productions of systemic and pulmonary pro-inflammatory mediators and promoted the release of anti-inflammatory mediators in lung. CONCLUSION: The inhibitory effects of DD treatment on pulmonary inflammatory response are not only related to reducing the extent of systemic inflammatory response, but also promote pulmonary anti-inflammatory production and regulate the balance of pulmonary pro-inflammatory mediators and anti-inflammatory cytokines. This specific regulatory effect protects the target organ from excessive inflammatory organ injury, discloses that DD has advantages in the treatment of endotoxic ARDS.