Effects of Yulangsan Extracts on Acute Lung Injury in Rats

Objective:To investigate the effect of Yulangsan(YLS) extracts on acute lung injury in rats.Method:The Wistar rats were randomly divided into control group,model group,dexamethasone group(3 mg·kg- 1),high and low dose groups of total YLS water extract(TYLS)(60,30 g·kg- 1) and flavonoids extracted from the roots of YLS(FYLS)(0.1,0.05 g·kg- 1).The animals were intragastrically treated with drugs for 7 days.The ALI model was set up by intraabdominal injection of 20% yeast suspension 5 mL·kg- 1,two time 30 minutes after the last medication.The lung wet / dry weight ratio(W / D) and the activity of myeloperoxidase(MPO) in the lung tissues were determined to assess lung injury.The expression of nuclear factor κB(NF-κB) p65 was analyzed by immunohistochemistry.The content of interleurin-1β(IL-1β) in the lung tissue was detected by ELISA.Meanwhile,the pathological change of lung was also observed by HE dying.Result:As compared with the control group,the lung W /D,MPO activity,IL-1β content and expression of NF-κB p65 were higher in the model group(P 0.01).HE dying showed inflammatory changes in lung in the model group.In TYLS high-and low-dose groups and FYLS high dose group,the lung W / D was(4.31 ± 0.15),(4.72 ± 0.35),(4.74 ± 0.23) respectively,was significantly lower compared with model group(P 0.05,P 0.01).The MPO activity was(1.000 ± 0.304),(0.956 ± 0.139) U·g- 1,IL-1β content was(265.58 ±47.05),(222.31 ± 53.99) ng·L- 1,NF-κB p65 expression level was(51.00 ±8.62) %,(48.88 ±11.80) %,in the high dose group of TYLS and FYLS respectively.The MPO activity and IL-1β content and NF-κB p65 expression level in lung were significantly reduced compared with model group(P 0.05,P 0.01).On the other hand,histopathological examination confirmed that the degree of lung injury in TYLS and FYLS groups was lessened.And high-dose groups showed the best effect.Conclusion:Preliminary administration of YLS extracts can alleviate the degree of pulmonary edema and pulmonary inflammation.The effects may be related to inhibiting the production of IL-1β by interfering the NF-κB path.