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Objective: To observe the budesonide (Bud) inhalation of bleomycin (BLM) induced pulmonary fibrosis in rat lung tissue matrix metalloproteinase -2 (matix of metalloproteinases-2, MMP-2) and tissue inhibitor of metalloproteinase -2 (tissue inhibitors of metalloproteinases-2, TIMP-2) expression of affect, and explore the mechanism of action of anti-pulmonary fibrosis. Methods: Wistar rats 45, were randomly divided into BLM model group (BLM group), 15 each the saline blank control group (NS) and Bud intervention group (Bud group), the BLM group and Bud group intratracheal instillation of BLM-induced lung The fibrosis, NS group under the same conditions perfusion NS. After intratracheal instillation of drugs, 1-6 days Bud group was given Bud inhalation, the remaining group under the same conditions to give NS inhalation. Each group at random on the 7th, 14th, 28th day the animals were sacrificed 5 each collection of lung tissue slices, HE and Masson staining, judgment alveolitis and pulmonary fibrosis of the lung tissue; immunohistochemical staining to detect MMP- 2 and TIMP-2 expression levels in the lung tissue. Results: (1) pathological observation, the NS group of lung tissue structure is normal, no inflammatory cell infiltration; compared with NS group, the 7th day of the BLM group heaviest alveolitis, alveolar space visible to a large number of inflammatory cell infiltration, 14 days alveolar intraluminal inflammatory cells was significantly reduced collagen significantly increased alveolar structural damage, widened alveolar septum 28 days pulmonary fibrosis severity of some of the alveolar spaces disappear, the formation of severe fibrosis; compared with the BLM group, Bud Group 7 and 14 days alveolitis of the lung tissue was significantly reduced (P lt; 0.05), 7, 14, 28 days significantly reduced pulmonary fibrosis (P lt; 0.05); (2) immunohistochemical staining, compared with NS group, BLM group on days 7, 14, 28 MMP-2 and TIMP-2 expression was significantly increased (P lt; 0.5); compared with the BLM group, MMP-2 and TIMP-2 expression was significantly reduced in the Bud Group on days 7, 14, 28 ( P lt; 0.05), Bud group 28 days MMP-2/TIMP2 ratio increased (P lt; 0.05). Conclusion: the BLM group and Bud group of lung tissue, MMP-2 and TIMP-2 expression was significantly increased, suggesting that MMP-2 and TIMP-2 were involved in the process of lung injury and pulmonary fibrosis, pulmonary fibrosis early (7 days), the increase in the expression of MMP-2, the enhanced role of the degradation of lung tissue, causing damage to the lung tissue, but also increased the expression of TIMP-2, MMP-2/TIMP-2 in proportion able to maintain a balance, which may not appear early accumulation of extracellular matrix (ECM) of the important reasons; reduction in the the late fibrosis stage and MMP-2 expression increased expression of TIMP-2, the proportion of the of MMP-2/TIMP-2 reduce its degradation weakened matrix deposition enhanced the formation of pulmonary fibrosis. Nebulized Bud can reduce the expression of MMP-2 and TIMP-2 in the lung tissue, and adjust the ratio of MMP-2/TIMP-2 a certain extent, delaying the process even inhibit lung fibrosis. Its mechanism may Bud has a strong anti-inflammatory effects, inhibit the proliferation and secretion of various inflammatory cells, so that a variety of cytokines such as interleukin (IL) -1 (IL-1), tumor necrosis factor (TNF-a), epidermal growth factor (EGF), decreased production, thereby inhibiting MMP-2 and TIMP-2 synthesis and activation.
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