Experimental Study On The Effect Of PNS Prevention And Treatment On Bleomycin-induced Idiopathic Pulmonary Fibrosis In Mice

The pathogenesis of pulmonary fibrosis is complicated, it is characterized with fibroblast hyperplasia, Epithelial cells apoptosis and deposition of collagen protein. The clinically effective therapy is deficient, the prognosis of this disease is not so better. Therefore, it is important to study the pathogenetic mechanisms and creating new treating scheme.PNS is one of the effective element extracted from notoginseng. It is one of the major components for notoginseng playing pharmacology.It owes various biological functions, including stop bleeding, remove blood stasis, detumescence, anemia, adjust the cell apoptosis functions and so on. To discuss the preventing and treating effect of PNS on idiopathic pulmonary fibrosis,mice model induced by bleomycin (BLM) was adopted. This thesis describes the effect and mechanisms of PNS on PF from aspects of integral and molecular level which can provides experimental foundation for more exact and scientific therapy. Methods and Results1 Role of observation on the prevention of PNS on pulmonary fibrosis 1.1 Methods 180 male C57BL/6 were randomly divided into 6 groups(30 mice in each group).Mice in the model control group;high,moderate and low PNS groups were injected. with a single dose of bleomycin by trachea,and mice in sham-model control group with same volume normal saline.1 day after the injection, oral administration of drug daily until they were killed 1 day before.PNS solution of different dosages(120mg,60mg,30mg/kg/d) was respectively given to mice in the high,moderate and low PNS group by gavages, while equal volume of normal saline was given to those in the sham-model control group and model control group, and an equal volume of prednisone(0.56mg·kg-1·d-1) was saline was given to those in positive medicine control group. Each animal in 7,14,28d pick eyeball take blood serum, observation, separationⅢserum collagen type (Ⅲ-C), IV collagen type (Ⅳ-C) and layer ankylosis protein (LN) and hyaluronic acid (HA), and take the content of lung tissue for HE Mallory stain, detection, lung tissue hydroxyproline (HYP) changes.1.2 Results PNS can modulate the level ofⅢ-collagen,Ⅳ-collagen,laminin and hyaluronic acid in serum compared with those levels in model control group and it can also lessen the hyperplasia of pulmonary fibrosis. It is indicated that PNS can prevent and treat pulmonary fibrosis2 Experimental study on mechanisms of PNS on pulmonary fibrosis2.1 The effect of PNS on cell apoptosis in pulmonary tissues of miceMechanisms of PNS on pulmonary fibrosis were discussed by the study on the level of cell apoptosis.By the method of TUNEL, observing the apoptosis of the lung. From the results, Pulmonary fibrosis in lung tissue apoptotic cells in mice increased significantly, mainly for the cell apoptosis of bronchial epithelium cells, alveolar epithelial cells, macrophages,and a few interstitial lung cells. In PNS dose group of mice could significantly reduce pulmonary fibrosis apoptosis of epithelial cells of lung tissue. It is suggested that PNS can play the role of the antioxidant fibrosis through inhibiting lung epithelial cell apoptosis.2.2 The effect of PNS on CatB and CatD in pulmonary tissues of miceMechanims of PNS on pulmonary fibrosis were discussed by observing the effect on CatB and CatD.The activition of CatB and CatD in the protein of pulmonary tissues was studied by means of immuno-histochemistry and Western blotting. It is showed that PNS can reduce the content of CatB and CatD in nucleoprotein. which means that one of mechanisms of PNS on pulmonary fibrosis is by inhibiting the activity of CatB and CatD.2.3 The effect of PNS on Bax and Bcl-2 in pulmonary tissues of miceThe effect of PNS on the lung tissue was investigated by detecting the activity of bax and bcl-2 at the protein and gene transcription level by using immuno-histochemistry and Real-time-PCR methods. The possible mechanism of PNS as anti-fibrosis is fully studied. The lung tissue is originated from experimentⅠ.①The expression of Bax is significantly increas-ed in the lung tissue of pulmonary fibrosis mice, it mainly expressed in the damaged lung bronchial epithelium cells, alveolar epithelial cells, and macrophages. However, the expres-sion of Bax in the interstitial lung cells are less significant, which means that hepatocytes is one of the main sources of Bax, bax plays an important role in the apoptosis of pulmonary fibrosis.②The expression of bcl-2 in the lung tissue of pulmonary fibrosis mice is signi-ficantly enhanced. Although there is expression in the fine bronchial epithelium cells and alveolar epithelial cells, the expression of bcl-2 in the interstitial lung cells is significantly increased, and some already enter the cell nucleus. It shows that bcl-2 are secreted by interstitial lung cells, bcl-2 plays an important role in inhibiting fibroblasts apoptosis.③The mRNA of Bax and bcl-2 significantly increased in the lung tissue of pulmonary fibrosis mice. The result shows that Bax and bcl-2 regulate the apoptosis of lung tissue cells of pulmonary fibrosis mice at least in protein transcription or translation level.④The results shows that the mechanism of PNS as the anti- pulmonary fibrosis is due to regulate the activity of Bax and bcl-2 of the lung tissue at the protein transcription and translation level2.4 The effect of PNS on Fas and FasL in pulmonary tissues of mice Mechanims of PNS on pulmonary fibrosis were discussed by observing the effect on Fas/FasL.The activition of CatB and CatD in the protein of pulmonary tissues was studied by means of immuno-histochemistry. It is showed that PNS can reduce the content of Fas/FasL in nucleoprotein. which means that one of mechanisms of PNS on pulmonary fibrosis is by inhibitting the activity of Fas/FasL.1 PNS can reduce the degree of pulmonary inflammation and fibrosis, and thus prevent and treat pulmonary fibrosis by adjusting the content of extracellular matrix in fibrotic mice by bleomycin-induced.2 Mechanisms of PNS on IPF lie in such aspects2.1 PNS can inhibit the activity of CatB and CatD in protein of pulmonary tissues.2.2 PNS can regulate the activity of Bax and Bcl-2 in protein of pulmonary tissues.2.3 PNS can inhibit the activity of Fas/FasL in protein of pulmonary tissues.In conclusion, we can conclude that PNS has a certain effect on the prevention and treatment of pulmonary fibrosis. The possible mechanism is due to inhibit the activity of CatB,CatD and Fas/FasL, regulate the activity of Bax/Bcl-2, inhibit the apoptosis of lung epithelial cells, and induce the apoptosis of fiber cells.