Study Of The Protective Effects Of Jidesheng Sheyao Tablet On The ALI/ARDS In Rats

OBJECTIVETo investigate the protective role of Jidesheng Sheyao Pian in lipopolysaccharide (LPS)-induced acute lung injury/ acute respiratory distress syndrome (ALI/ARDS) in rats. METHODFifty male Wistar rats were randomly divided into 6 groups. All rats, except normal control group, were administrated with LPS by intravenous injection to induce acute lung injury. The rats in positive group and three different dosage groups were treated by dexamethasone (3mg.kg-1, iv,one time), low dosage(0.8g.kg-1), mid dosage(1.6g.kg-1) and high dosage(3.2g.kg-1) of Jidesheng Sheyao Tablet(oral,three times,qd) respectively before LPS-induced ALI. Each rat in normal control group received injection of 1ml normal saline. The animals were sacrificed after injection of LPS for 2 hours, and then the lung index was calculated, the histopathology of the lung injury was observed by light microscope and electron microscope, the expression of matrix metalloproteinase-2 (MMP-2), matrix metalloproteinase-9 (MMP-9) proteins in the lung tissues and their activity in the bronchoalveolar lavage fluid (BALF) and the lung homogenates were detected by immunohistochemistry and zymography separately. RT-PCR technology was used to determine the expression of MMP-2,-9 mRNA in the lung tissues. RESULTCompared with model group, the lung indexes were significantly decreased in the drug groups (P<0.05), the positive group was also decreased in different degree and the high dosage group was lower than that of positive control(P﹤0.01). It was found that the degrees of lung injury including lung swelling, neutrophil cells infiltration,hemorrhage and mitochondria vacuolar degeneration, inter-cell junction disappearance in the capillary endothelial cell,basement membrane becoming thin and rupture, red blood cell leaking out, exudation gathering in the lung alveolus in the drug groups showed lighter in dose-dependent manner than that of model group. And the expression of MMP-2 and MMP-9 proteins in the lung tissues was obviously inhibited in the high dosage group and their activity in lung homogenate and BALF also presented dose-dependent inhibition (P﹤0.01) except the activity of MMP-2 in the lung tissues.Meanwhile, the expression of MMP-9, MMP-2 mRNA was also markedly depressed in Jidesheng Sheyao groups.