The TNF-α/TNFR/NF-κB pathway in regulating alveolar macrophage apoptosis in coal workers' pneumoconiosis / 中国职业医学

OBJECTIVE: To study the mechanism of tumor necrosis factor( TNF)-α and its receptor( TNFR) signal transduction pathways in regulating cell apoptosis of alveolar macrophage( AM) in coal workers' pneumoconiosis( CWP).METHODS: Twenty-four coal workers with pneumoconiosis at stage Ⅰ were selected as CWP group and four observation subjects exposed to coal were chosen as observation group by using simple random sampling method. The bronchoalveolar lavage fluids of whole-lung lavage of two groups were collected. AMs were separated and purified. Then they were divided into 6 groups: a control group,a superoxide dismutase( SOD) group,a TNF/TNFR group,an anti-TNF-α antibody group,a Caspase-8 suppression group and a nuclear factor-κB( NF-κB) suppression group. The AMs of 6 groups with corresponding treatment were cultivated. After 24 hours,the cells were harvested and proteins extracted. The relative expression of TNF-α,TNFR1,TNFR2,Caspase-8,Caspase-3,NF-κB P50 and NF-κB P65 protein was detected by Western blotting. RESULTS: The protein relative expression of TNF-α,TNFR2,Caspase-8,Caspase-3,NF-κB P50 and NF-κB P65 in CWP group was significantly higher than those in the observation group( P < 0. 05). The protein relative expression of TNF-α,TNFR1,Caspase-8,Caspase-3 and NF-κB P50 in the TNF/TNFR group and the anti-TNF-αantibody group was lower than that of the control group( P < 0. 05). The above indexes in the anti-TNF-α antibody group were lower than that of the NF-κB suppression group( P < 0. 05). The protein relative expression of TNFR1,Caspase-8and Caspase-3 in the TNF/TNFR group was higher than that of the SOD group and the Caspase-8 suppression group( P <0. 05). The protein relative expression of TNFR1,Caspase-8 and NF-κB P50 in the TNF/TNFR group was lower than that of the NF-κB suppression group( P < 0. 05). Among the CWP patients,the relative expression of TNFR2 and NF-κB P65 in the TNF/TNFR group was lower than that of the control group( P < 0. 05),and higher than that of the SOD group( P <0. 05). CONCLUSION: AM apoptosis mediated by TNF-α/TNFR/NF-κB signal transduction pathway plays an important role in the occurrence and development of CWP. The TNF-α/TNFR/NF-κB signal transduction pathways inhibited or blocked at different stages can affect the expression of proteins related to AM apoptosis.

Relationship between genetic polymorphisms of matrix metalloproteinase-2 and -3 and susceptibility to silicosis / 中华劳动卫生职业病杂志

<p><b>OBJECTIVE</b>To investigate the relationship between the genetic polymorphisms of matrix metalloproteinase-2 (MMP-2) (-735) and matrix metalloproteinase-3 (MMP-3) (-1171) and the susceptibility to silicosis.</p><p><b>METHODS</b>A case-control study was conducted in 113 patients diagnosed with stage I silicosis (case group) and 115 dust-exposed workers without silicosis (control group); the two groups had the same sex, ethnic group, and type of dust and similar age and cumulative exposure time. Polymerase chain reaction-restriction fragment length polymorphism was used to determine the genotypes of MMP-2 (-735) and MMP-3 (-1171).</p><p><b>RESULTS</b>No significant difference was observed in age, cumulative exposure time, or smoking rate between cases and controls (P > 0.05). The frequencies of genotypes C/C, C/T, and T/T at MMP-2 C-735T in the case group were 57.5% (65/113), 31.0% (35/113), and 11.5% (13/113), respectively, which were significantly different from those of the control group (69.6% (80/115), 26.9% (31/115), and 3.5% (4/115)), χ² = 6.542, P < 0.05). The frequencies of T allele in cases and controls were 27.0% and 17.0%, respectively, which were significantly different from each other χ² = 6.704, P < 0.05). Carriage of T allele at MMP-2 C-735T increased the risk of silicosis (OR = 1.811, 95% CI: 1.151-2.847). The frequencies of genotypes 6A/6A, 5A/6A, and 5A/5A at MMP-3 A-1171A were 67.2% (76/113), 24.8% (28/113), and 8.0% (9/113), respectively, in the case group, versus 59.1% (68/115), 37.4% (43/115), and 3.5% (4/115) in the control group (χ² = 5.519, P > 0.05).</p><p><b>CONCLUSION</b>Genetic polymorphism at MMP-2 C-735T is significantly associated with the development of silicosis. Carriage of T allele increases the risk of silicosis among workers exposed to dust. No significant association was found between MMP-3 A-1171A polymorphism and silicosis in this study.</p>

The Effect of Bisphenol A and Dibutyphthlate Treated With Rat Liver S9 on Proliferation of MCF-7 Cells / 环境与健康杂志

Objective To study the effect of bisphenol A (BPA) and dibutyphthlate (DBP) treated with Rat Liver S9 on proliferation MCF-7 cells. Methods Added the positive control 17?-estradiol (E2) and compounds of BPA and DBP with the effect of Rat Liver S9 to MCF-7 cells proliferation respectively and determinated the quantity of MCF-7 cells with MTT assay. Results The activity of E2 and DBP stimulated MCF-7 cells decreasing significantly with the effect of Liver S9 than without the effect of Liver S9, while BPA stimulated MCF-7 cells increasing significantly with the effect of Liver S9 than that without the effect of Liver S9. Conclusion E2 and DBP have a lower estrogenic activity with the effect of S9 than without the effect of S9. BPA shows a higher estrogenic activity with the effect of S9 than without the effect of S9.