金荞麦对克雷伯杆菌肺炎大鼠肺组织损伤的保护作用及其机制

Protection and Mechanism of Fagopyrum cymosum on Lung Injury in Rats with Klebsiella pneumonia

目的:研究金荞麦对克雷伯杆菌肺炎大鼠肺组织损伤的保护作用及其机制。方法:复制克雷伯杆菌肺炎大鼠模型。随机将雄性SD大鼠分成正常对照组、模型组、金荞麦(生药6、3、1.5 g/kg)组、左氧氟沙星(25 mg/kg)组。观察肺组织的病理改变,测大鼠血清中IL-1β、IL-6、IL-8、TNF-α、ICAM-1及INF-γ含量,采用免疫组化测肺组织中TNF-α、ICAM-1及NF-κB p65蛋白表达和原位杂交法测肺组织巨噬细胞炎症蛋白-2(MIP-2)mRNA表达。结果:模型组大鼠的肺脏组织损伤明显,血清中IL-1β、IL-6、IL-8、TNF-α、ICAM-1及INF-γ含量升高,模型组大鼠肺组织中TNF-α、ICAM-1、NF-κB p65的蛋白表达和MIP-2mRNA的表达均较对照组显著增强(P<0.05或P<0.01)。与模型组比较,金荞麦组和左氧氟沙星组大鼠肺组织损伤明显改善,血清中IL-6、IL-8、CAM-1及IFN-γ含量显著降低(P<0.05或P<0.01),肺组织中TNF-α、ICAM-1、NF-κB p65蛋白表达和MIP-2 mRNA的表达显著减弱(P<0.05或P<0.01)。结论:TNF-α、ICAM-1、NF-κB p65及MIP-2的表达上调参与了肺炎大鼠肺脏组织的损伤,金荞麦通过下调其表达来保护肺炎大鼠肺组织的损伤作用。

Objective：To study the mechanism of protective effect of Fagopyrum cymosum on lung injury induced by Klebsiella pneumonia in rats. Methods ： The model of rats with Klebsiella pneumonia was established. The male SD rats were randomly divided into control group,model group,Fagopyrum cymosum （6,3,1.5 g/kg） three groups,levofloxacin （25 mg/kg） group. The pathological change of lung was observed. The content of IL-lfl, IL-6, IL-8, TNF-α, ICAM-1, INF-T in serum were measured by radioimmunoassay and Elisa. TNF-α, ICAM-1 ,NF-KB p65 protein expressions were measured by immunohistochemistry. MIP-2mRNA expression was de- tected by in situ hybridization. Results ： The rats of model group had obvious lung injury, but those of Fagopyrum cymosum and levoflox- acin groups had less injury. The contents of IL-lβ, IL-6, IL-8, TNF-α, ICAM-1 and INF-T in serum and the expressions of TNF-α, ICAM-1, NF-KB p65 and MIP - 2mRNA of model group were significantly higher than those of the control group （ P 〈 0.05 or P 〈 O. 01 ） ,while the indexes of Fagopyrum cymosum and levofloxaein groups were significantly lower than those of model group（ P 〈 0. 05 or P 〈 O. 01 ）. Conclusion： The lung injury induced by Klebsiella pneumonia is related to TNF-α, ICAM-1, NF-KB p65 and MIP- 2mRNA. To decrease the excessive expression of TNF-α,ICAM-1 ,NF-KB p65 and MIP-2mRNA might be the main mechanism of pro- tective effect of Fagopyrum cymosum on lung injury.