High Mobility Group Protein-1and Its Receptor In The Pathogenesis Of Pneumoconiosis

Objective:To explore the role of high mobility group box protein1(HMGB-1) and soluble receptor of advanced glycation end-products (sRAGE) in pneumoconiosis incidence in the crowd, study the effects of silicon dioxide (SiO2) stimulation on the receptor of advanced glycation end-products(RAGE), ligand-calgranulin (S100) and HMGB-1in16human bronchial epithelial cells (16HBE).Methods:1. Choose Ⅰ,Ⅱ,Ⅲ period of pneumoconiosis patients exposed to silicon coal dust for25-30year from XiShan mineral bureau as experimental subjects, select people without exposure from the same coal mine as healthy control subjects, respectively. Collect the blood of experimental group and healthy control group, use enzyme-linked immunosorbent assay (ELISA) to measure the expression of HMGB-1, RAGE in serum, and detect pulmonary ventilation function at the same time.2. Culture the16HBE cells in logarithmic phase with100μg/ml SiO2. Experiment is divided into four groups:blank control group only with serum-free medium; negative control group; three experimental groups with100μg/ml SiO2stimulation, observe4h,24h,48h, each group set four parallel control. Use cell fluorescent immunohistochemical technique to determine the expression of RAGE, S100; Western blot technique to determine the content of HMGB-1protein.Results:1. The serum results of pneumoconiosis experiment showed that:1) Compared with normal control group, the sRAGE content of pneumoconiosis patients in experimental group were higher, the difference was statistically significant (P<0.05), the sRAGE expression increased with pneumoconiosis stage rising, the difference was statistically significant (P<0.05).2) HMGB-1is expressed in normal control group and patients with pneumoconiosis, the difference is statistically significant (P<0.05).In different periods of pneumoconiosis, HMGB-1expression rised in Ⅰ,Ⅱ but reduced in Ⅲ period, the difference was statistically significant(P<0.05).3) The results of FVC, FEV1/FVC, FEV1showed pulmonary ventilation function reduced with pneumoconiosis stage rising, the difference was statistically significant (P<0.05). Lung ventilation function index of FVC, FEV1/FVC, FEV1and coal silicosis patients serum levels of HMGB1correlation analysis showed that HMGB1and lung function impairment in Ⅰ, Ⅱ period coal silicosis group has certain parallel relationship, through the statistical correlation analysis, I period coal silicosis of HMGB1and pulmonary function of FVC, FEV1/FVC, FEV1correlation coefficient is0.764,0.540,0.540respectively(P<0.05). Ⅱ period HMGB1and lung function in coal silicosis of FVC, FEV1/FVC,FEV1of correlation coefficient is0.825,0.512,0.512respectively(P<0.05).Except the FEV1/FVC in two coal silicosis of HMGB1and lung function were significant negative correlation.2. The results of16HBE cells with SiO2stimulation showed that:1)S100level significantly increased with the extension of time in the group with100μg/ml SiO2, the difference was statistically significant (P<0.05), the expression of S100was higher in the experimental group than the blank control group, the difference had statistical significance (P<0.05).2) The fluorescence optical density value of RAGE in the experimental group was lower than the blank control group at each observation time point, the difference was statistically significant (P<0.05), and the fluorescence optical density value of RAGE decreased with time extension, the difference had statistical significance (P<0.05).3) The expression of HMGB-1in the blank group was higher than the experimental group,the difference was statistically significant (P<0.05),In different periods of pneumoconiosis,HMGB-1expression rised in Ⅰ,Ⅱ but reduced in Ⅲ period,the difference was statistically significant (P<0.05).Conclusion:1. The sRAGE protein is expressed in serum of normal human and patients with pneumoconiosis,and has time-effect relationship with pneumoconiosis stage.HMGB1is expressed in normal people and has a close relationship with pathological process of pneumoconiosis. Occupational exposure to silicon coal dust can lead to significant reduction of pulmonary ventilation function,and pulmonary ventilation function appears a progressive decline with pneumoconiosis stage rising.2. RAGE is highly expressed on normal human bronchial epithelial cell membrane, SiO2can reduce its expression.3. SiO2can induce the secretion of S100in16HBE cells,and the secretion grows in quantity with the extension of action time.HMGB1is higher at the early stage of the pneumoconiosis is progressive, the late because of sRAGE inhibits inflammation, HMGB1expression decreased.