Humans ; Proteomics ; methods ; Silicosis ; metabolism ; Specimen Handling ; methods

OBJECTIVETo analyze the change in nitration tyrosine, NO(2)(-)/NO(3)(-)level in induced sputum of silicosis patients and dust exposure workers and to evaluate the approach and feasibility of nitric oxide (NO) metabolites as early detection indicators of silicosis.

METHODSNitration tyrosine, NO(2)(-)/NO(3)(-)concentration in induced sputum of 80 dust exposure workers, 84 silicosis patients, 30 logistic personnel with no history of exposure to silica dust were determined and the relationship among Nitration tyrosine, NO(2)(-)/NO(3)(-)level and dust exposure years as well as pulmonary function tests were analyzed.

RESULTSNO(2)(-)/NO(3)(-)level among exposed group [60.30 (46.58) micromol/l] was significantly higher than the control group [36.90 (22.28) micromol/l], (P < 0.05), and the level of NO(2)(-)/NO(3)(-)among the cases [79.65 (89.10) micromol/l] was significantly higher than exposed group as well as the control group (P < 0.05). Compared with control, the level of nitration tyrosine in exposed group [3.51 (0.46) nmol/l] and the cases [3.48 (0.49) nmol/l] was significantly higher (P < 0.05). NO(2)(-)/NO(3)(-)level and dust exposure years were positively correlated (r = 0.3733 and 0.3830 respectively P < 0.05); NO(2)(-)/NO(3)(-)level and pulmonary function tests (FVC%, FEV1.0%, PEF%, MEF25%, MEF50%) were negatively correlated (r = 0.1540, 0.1723, 0.1535, 0.1485, 0.1643 respectively, P < 0.05). There was no correlation between nitration tyrosine and dust exposure years (P > 0.05), no correlation between nitration tyrosine and pulmonary function test (P > 0.05).

CONCLUSIONThe level of NO(2)(-)/NO(3)(-)level in induced sputum has a positive correlation with exposure to dust, suggesting that there will be a certain feasibility of the NO(2)(-)/NO(3)(-)as indicators of early detection of silicosis.

Adult ; Humans ; Middle Aged ; Nitrates ; metabolism ; Nitrites ; metabolism ; Silicosis ; metabolism ; Sputum ; metabolism ; Tyrosine ; metabolism

Dust ; Humans ; Inflammation ; metabolism ; Intercellular Signaling Peptides and Proteins ; metabolism ; Silicon Dioxide ; adverse effects ; Silicosis ; metabolism

Humans ; Interleukin-18 ; chemistry ; metabolism ; Pulmonary Fibrosis ; etiology ; pathology ; Silicosis ; complications ; pathology ; physiopathology

Aged ; Humans ; Male ; Middle Aged ; Receptors, Interleukin-2 ; blood ; Silicosis ; blood ; classification ; T-Lymphocyte Subsets ; metabolism

Adult ; Biomarkers ; blood ; Blood Proteins ; metabolism ; Humans ; Male ; Middle Aged ; Silicosis ; blood

Objective: To study the effect of anti-fibrotic tetrapeptide N-acetyl-seryl-aspartyl-lysyl-proline (Ac-SDKP) on phosphorylated heat shock protein 27 (P-HSP27) and zinc finger family transcriptional repressor 1 (SNAI1) expression to explore the anti-silicosis fibrosis effect of Ac-SDKP. Methods: In December 2014, the rat silicosis animal model was prepared by one-time bronchial infusion of silicon dioxide (SiO(2)) dust. 80 SPF healthy adult Wistar rats were selected, and the rats were divided into 8 groups according to the random number table method, 10 in each group. Model control group for 4 weeks (feeding for 4 weeks) , model control group for 8 weeks (feeding for 8 weeks) : bronchial perfusion with normal saline 1.0 ml per animal. Silicosis model group for 4 weeks (feeding for 4 weeks) and silicosis model group for 8 weeks (feeding for 8 weeks) : bronchial perfusion of 50 mg/ml SiO(2) suspension 1.0 ml per animal. Ac-SDKP administration group for 4 weeks (feeding for 4 weeks) , Ac-SDKP administration group for 8 weeks (feeding for 8 weeks) : Ac-SDKP 800 μg·kg(-1)·d(-1) was administered by intraperitoneal pump. Ac-SDKP preventive treatment group: 48 h after Ac-SDKP 800 μg·kg(-1)·d(-1) administration, bronchial perfusion of SiO(2) suspension 1.0 ml per animal, raised for 8 weeks. Ac-SDKP anti-fibrosis treatment group: after bronchial perfusion of 1.0 ml of SiO(2) suspension for 4 weeks, Ac-SDKP 800 μg·kg(-1)·d(-1) was administered for 4 weeks. Western blotting was used to detect the expression of P-HSP27, SNAI1, α-smooth muscle actin (α-SMA) , and collage typeⅠ and Ⅲ in each group. The expression of P-HSP27 and SNAI1 was detected by immunohistochemistry, and the co-localized expression of P-HSP27 and α-SMA was detected by laser confocal microscopy. Results: Compared with the model control group, the expressions of P-HSP27, SNAI1, α-SMA, and collage typeⅠ and Ⅲ in the silicosis fibrosis area of the rats in the silicosis model group were enhanced, and the differences were statistically significant (P<0.05) . After Ac-SDKP intervention, compared with silicosis model group for 8 weeks, the expressions of P-HSP27, SNAI1 α-SMA, and collage typeⅠ and Ⅲ in the Ac-SDKP preventive and anti-fibrosis treatment groups were significantly decreased, and the differences were statistically significant (P<0.05) . However, the expressions of P-HSP27 SNAI1, and collage typeⅠ and Ⅲ between the Ac-SDKP administration group and the model control group did not change significantly, and the differences were not statistically significant (P>0.05) . Laser confocal results showed that the positive cells expressing P-HSP27 and α-SMA in the lung tissue of the silicosis model group were more than those in the model control group. Compared with the silicosis model group, the Ac-SDKP prevention and anti-fibrosis treatment groups expressing the positive cells of P-HSP27 and α-SMA decreased. Compared with the model control group for 8 weeks, there were some double-positive cells expressing P-HSP27 and α-SMA in the nodules of the silicosis model group for 8 weeks. Conclusion: Ac-SDKP may play an anti-silicic fibrosis effect by regulating the P-HSP27/SNAI1 pathway.
Animals ; HSP27 Heat-Shock Proteins ; Oligopeptides ; Rats ; Rats, Wistar ; Silicon Dioxide ; Silicosis/metabolism*

Bronchoalveolar Lavage Fluid ; Humans ; Interleukin-1beta ; metabolism ; Macrophages, Alveolar ; cytology ; drug effects ; metabolism ; Silicon Dioxide ; adverse effects ; Silicosis ; metabolism

OBJECTIVETo perform a comparative proteomic analysis for identification of pulmonary proteins related to the progression of silicosis and anti-fibrotic effect of N-acetyl-seryl-aspartyl-lysyl-proline (Ac-SDKP).

METHODSBronchial instillation of SiO₂powder (for 4 or 8 weeks) was applied in rats to establish a silicosis model. Ac-SDKP treatment was performed before (prevention group) or after (treatment group) SiO₂instillation. The control group was treated by bronchial instillation of sodium chloride solution of the same volume as SiO₂powder for 4 or 8 weeks. Proteins in lung tissue were separated by two-dimensional gel electrophoresis and stained with colloidal Coomassie brilliant blue. The gel images were scanned with the Lab Scan III system and analyzed with Imagemaster 6.0. The protein spots with significant differences between two groups (i.e., P value was less than 0.05 in One-way ANOVA) and with a change in volume over 30% were defined as differential proteins. Comparison was performed between the silicosis group and control group after 4 or 8 weeks, between the Ac-SDKP treatment group and silicosis group after 8 weeks, and between the Ac-SDKP prevention group and silicosis group after 8 weeks. The differentially expressed proteins were subjected to in-gel digestion with trypsin and MALDI-TOF-MS and Mascot search engine analysis to identify these proteins.

RESULTSThirty-three differential proteins were identified. In comparison with the control group (4 weeks), the silicosis group (4 weeks) had 17 up-regulated proteins and 11 down-regulated proteins. In comparison with the control group (8 weeks), the silicosis group (8 weeks) had 16 up-regulated proteins and 12 down-regulated proteins. In comparison with the silicosis group (8 weeks), the Ac-SDKP treatment group had 5 up-regulated proteins and 6 down-regulated proteins, and the Ac-SDKP prevention group had 8 up-regulated proteins and 10 down-regulated proteins.

CONCLUSIONCritical regulatory proteins related to silicotic fibrosis and anti-silicotic effect of Ac-SDKP have been identified. These proteins may play an important role in proliferation, apoptosis, inflammation, epithelial-mesenchymal transition, and signal transduction in silicosis.

Animals ; Disease Models, Animal ; Lung ; metabolism ; Male ; Oligopeptides ; therapeutic use ; Proteome ; metabolism ; Rats ; Rats, Wistar ; Silicosis ; drug therapy ; metabolism

Aged ; Case-Control Studies ; Humans ; Male ; Malondialdehyde ; metabolism ; Middle Aged ; Oxidation-Reduction ; Serum ; metabolism ; Silicosis ; blood ; Superoxide Dismutase ; metabolism