RAGE And Ligands In Pulmonary Fibrosis Silicosis

Objective: To study the effect of RAGE (Receptor for Advanced Glycation End-Products) and its ligand——HMGB-1/S100 in incidence of silicosis.Methods: Preparation of silicosis model: 60 healthy male Kunming mice were randomly divided into SiO2 exposure group and control group. SiO₂ group set 3,7,14,21 and 42 days 5 observation time points.6 in each group. Dust with dye injection method for tracheotomy, a dose of 400mg/kg/only. Sample collection and index determination: animals were killed at the appropriate observation period, abdominal aortic blood, serum collected. Lung washing fluid was collected by bronchial washing fluid. Application of cell smear, Put Washing fluid under a microscope count of the number of neutrophils, macrophages and lymphocytes. Remove the Lung tissue.left lung frozen in liquid nitrogen, extraction of tissue protein. Right lung was fixed with 10% paraformaldehyde, embedded in paraffin for pathological slice thickness is 4μm. Enzyme-linked immunosorbent assay (ELISA) in serum HMGB-1 and tumor necrosis factor-αlevels, and lung wash fluid levels of HMGB-1. By Western blot quantitative detection of the expression of RAGE in lung tissue; immunofluorescence method using qualitative detection of RAGE and S100 in the mouse lung tissue.Results: 1.lung washing fluid inflammatory cell counts showed: alveolar macrophage of SiO2 dust stained s 3-7 days significantly increased, then dust with prolonged staining, decreased macrophage; the peak of neutrophil 7-14 days in the infected dust, dust stained lymphocytes mainly in the performance of 21 days significantly increased liquid dye wash the dust of three lung levels of inflammatory cells compared with control group statistically significant difference, P <0.01 ; dye dust for 42 days, inflammatory cells decreased. 2.lung washing fluid TNF-αand HMGB-1 test results showed that: at all time points, the experimental group TNF-αand HMGB-1 was significantly higher than the control group, showed statistically significant difference, P <0.05 The experimental group compared different time points, TNF-αin the 3-14 day period, TNF-αincreased with time, 21 days later with the observed decline time; and HMGB-1 levels observed with prolonged Skyrocketed. Comparison at each time point was statistically significantly different. 3.Serum HMGB-1 results showed that: the experimental group during the observation period 3²1 days, but increased with time, 42 days showed decreased; 4. immunohistochemistry and Western bolt results of lung tissue seen RAGE: RAGE in lung tissue Dust with dyeing time fluorescence intensity gradually decreased, the difference shows a statistically significant difference, P <0.05, and Western bolt results. In lung tissue, RAGE was mainly localized in bronchial epithelial cells, alveolar macrophages, present in the cell membrane and cytoplasm. 5. S100 immunohistochemistry assay results showed that the dust over extended fluorescence staining was significantly increased, compared with the control was statistically significant, (P <0.05). S100 located in the cytoplasm, membrane and lung tissue. Conclusion:1. Silicosis model of inflammation mainly in the 7-14 days, neutrophils, TNF-αin the inflammatory response; 2. In the pathogenesis of silicosis, HMGB-1 and S100 continue to rise, RAGE expression was significantly decreased, suggesting HMGB-1.