Effects of Hedysari Flavonoids on TGF-β1 and Ultrastructure in Lung Tissue of Rats with Pulmonary Fibrosis / 中国中医药信息杂志

ABSTRACT

Objective To observe the effects of Hedysari flavonoids on TGF-β1 and ultrastructure in lung tissue of rats with pulmonary fibrosis, and explore its mechanism. Methods Wistar rats were randomly divided into blank group, model group, prednisone group and Hedysari flavonoids high-, medium- and low-dose groups. Pulmonary fibrosis model was established by injection of bleomycin via trachea. After 24 h, rats were given drugs by gavage in all treatment groups once daily. The expression of TGF-β1 in lung tissue was detected by immunohistochemistry on d7, d14 and d28, and ultrastructure wasobserved by transmission electron microscope on d28. Results The positive expression of TGF-β1 was found in a few bronchiolar epithelial cell cytoplasm of blank group. Compared with the blank group, the positive expression of TGF-β1 on bronchial epithelial cell significantly increased (P<0.05) on d7, d14, and d28 in model group. Compared with the model group, the positive expression of TGF-β1 were significantly decreased (P<0.05, P<0.01) in Hedysari flavonoids high- and medium-dose groups and prednisone group on d7, d14 and d28. With electron microscopy, collagen fibers within the mediastinum in rat alveolar in model group were significantly increased, cell cytoplasm mitochondria was swollen in type Ⅱ epithelial cell.Mitochondrial crista was broken or disappeared, lamellar bodies significantly reduced. Collagen fibers reduced significantly in all treatment groups, which can improve and change ultrastructure on type Ⅱ epithelial cell. Conclusion Hedysari flavonoids can significantly reduce pathological damage and extracellular matrix deposition of rats with pulmonary fibrosis, which may have connection with inhibiting of TGF-β1 expression.