Effects And Mechanisms Of Alstonia Scholaris On Bleomycin-induced Pulmonary Injury

AIM: Pulmonary fibrosis (PF) is a kind of serious lung diseases and is the common final of many pulmonary diseases. However the mechanism is still unclear to us and there is no satisfactory drug therapy for it. Glucocorticoids is the first choice in treating PF nowadays,yet many studies indicated that it could induce some serious diseases such as osteoporosis and so on. Traditional Chinese medicine has a bright future in preventing and treating PF and many have made great progress in clinical therapy. In this study, we interfered the process of fibrosis with a Chinese medicine Dengtaishu (Alstonia scholaris) to study its protect effect on early experimental pulmonary fibrosis and explored the potential mechanism in BL-induced animal'PF,then settle a theoretical foundation for its clinical use.METHODS: (1) Put Alstonia scholaris powder 0.5g into 15mL 95% alcohol solution, heat and recirculate for 2h, cool down, and place in hypersound 20 min. then filter and add 5mL 95% alcohol solution in it to dissolve. And make standard leave powder solution in the same way. point these two solutions on the SG plant ,the developing agent is CHCl3-CH3OH(9:1).The developer is 10% sulfuric acid alcohol solution. The heat and observe the blot. compared with the reference, we can get the same color blot at the same place on the same SG plant. (2) 48 SD rats were randomly divided into Control groups, Model groups, Dengyaishu groups(dose:1g·kg-1), predniosone groups and were given one intratracheal injection of 1mg of bleomycin in 0.01mL 0.9% saline or an equivalent volume of 0.9% saline to set a model of pulmonary fibrosis. On day 2, each BL group was given Dengtaishu abstract, predniosone respectively except BL control group. On day 7, 14, 6 rats in each group were sacrificed and lungs were harvested. The right lungs were fixed in 10% formaldehyde for 1 day,paraffin-embedded and sliced for histopathological studies (HE staining),the left lungs were homogenized for biochemical assays of SOD activity and MDA,GSH,TNF-αcontent. (3) 40 BLAC mice were randomly divided into Control groups, Model groups, Dengyaishu groups(dose:1g·kg-1), predniosone groups and were given one intratracheal injection of 1mg of bleomycin in 0.01mL 0.9% saline or an equivalent volume of 0.9% saline to set a model of pulmonary fibrosis. On day 2, each BL group was given Dengtaishu abstract, predniosone respectively except BL control group. On day 90, 10 mice in each group were sacrificed and lungs were harvested. The right lungs were fixed in 10% formaldehyde for 1 day,paraffin-embedded and sliced for histopathological studies (HE,Masson staining),the left lungs were homogenized for biochemical assays of SOD activity and MDA,GSH,TNF-αcontent.RESULT: (1) Compared with the reference, we can get the same color blot at the same place on the same SG plant. So we can concluded that the same component in the bark and the leave. (2) Compared to model group, alveolitis were alleviated in Dengtaishu group significantly; pathological grading of pulmonary alveolitis show that aleveolitis were remarkable alleviated in Dengtaishu group and predniosone group(P<0.01), 0～Ⅰ-rate pulmonary alveolitis took a dominant position in Dengtaishu group,Ⅰ～Ⅱ-rate pulmonary alveolitis were displayed in predniosone group.On day 7, MDA,TNF-αcontents of homogenized lungs in Dengtaishu group lowed (P<0.05), GSH contents of homogenized lungs in Dengtaishu group and predniosone group increased (P<0.05);on day 14, SOD GSH contents of homogenized lungs in Dengtaishu group increased (P<0.05), MDA contents lowed (P<0.05), TNF-αcontents of homogenized lungs in Dengtaishu group lowed (P<0.05). (3) On day 90, MDA,TNF-αcontents of homogenized lungs in Dengtaishu group lowed (P<0.05), GSH contents of homogenized lungs in Dengtaishu group and predniosone group increased (P<0.05); Masson staining show that Dengtaishu can inhibited and decreased the pulmonary fibrosis in mice with bleomycin.CONCLUSION: The results of our experiments showed that Dengtaishu abstract and Prednisolone could retard and restrain Pulmonary alveolitis in rats with BL-induced. Dengtaishu could decrease TNF-αcontent in homogenate of lung, heighten the activity of SOD, lower damnification of lipid peroxide(LPO), enhance the power of eliminating and restrain Oxygen radical, alleviate inflammation and decrease phlogistic cells, So effect on experimental pulmonary fibrosis. The possible mechanisms which Dengtaishu preventing and treating pulmonary fibrosis is restrain TNF-αexpression , improve the oxidation/deoxidation balance , restrain inflammation. and then , to alleviate and restrain pulmonary fibrosis.