Role of protein kinase C/NF-kappa B signal pathway In activation of T lymphocytes In human exposed to coal-arsenic / 中国地方病学杂志

Objective To investigate the activation of T lymphocytes in human peripheral blood and the signaling molecules in protein kinase C/nuclear factor KB(PKC/NF-κB) pathway expressivity or activity changes in human peripheral blood mononuclear cells(PBMCs) exposed to coal-arsenic,to explore the role of PKC/NF-κB signal pathway in activation of T cells in human exposed to coal-arsenic. Methods Blood samples were collected from individuals who lived in arsenism area of coal-burning in Guizhou province, and were divided into asymptomatically exposed group (12),mild arsenism group (33),moderate arsenism group (34) and severe arscnism group (15) according to Diagnosis Standard for Endemic Arsenism (WS/T 211-2001). The individuals who lived in non-arsenism area were control group(27). The ratio of activated T ceils was analyzed by flow cytometry. DNA binding activity of NF-κB in PBMCs was evaluated by electrophoretic mobility shift assay(EMSA). The expression of PKCθ and phospho-PKCθ(pPKCθ) in PBMCs were detected with western blotting analysis. Results The ratio of activating T cells in asymptomatically exposed group[(21.76±15.31)%],mild arsenism group[(18.41±11.36)%],moderate arsenism group[(17.78±11.93)%]and severe arsenism group[(18.79±13.38)%]were all higher than that of control group[(3.19±2.12)%],the difference among all groups being statistically significant(F = 7.893,P < 0.05). DNA binding activity of PBMCs NF-κB in asymptomatically exposed group,mild arsenism group,moderate arsenism group and severe arsenism group(1.49±0.24,1.58±0.30,1.57±0.34,1.51±0.16) were higher than that of the control group(1.30±0.17),the difference being statistically sign/ficant(P < 0.05 or < 0.01). The expression of PBMCs pPKCθ in mild arsenism group,moderate arsenism group and severe arsenism group(0.64± 0.14,0.64±0.27,0.62±0.12) were all lower than that of the control group(0.93±0.20),the difference being statistically significant(P < 0.05). There were significant negative correlations between the expression of pPKCθ and the activity of NF-κB(r =-0.565,P < 0.01). There were significant positive correlations between the activity of NF-κB and the ratio of activating T cells(r = 0.546,P < 0.01). Conclusion Coal-arsenic enhances the DNA binding activity of NF-κB,reduces the expression of PBMCs pPKCθ in human PBMCs and up-regulates the activity of T cells. It suggests that the PKC/NF-κB signal might be one of transduction pathway via activating of T cells by coal-arsenic.

Comparative analysis of environmental risk factors in nine years in an area polluted by arsenic coal-burning in Guizhou Province / 中国地方病学杂志

Objective To comparatively analyze the changes of environmental risk factors in 9 years in an area polluted by arsenic coal-burning in Xingren County of Guizhou Province,in order to provide evidence for reasoning the occurrence and development as well as its effective prevention and control.Methods Epidemiological sampling methods was used to conduct follow-up investigation on 181 arsenism patients who were diagnosed in 1998 in arsenic polluted area.Control group included 65 residents who lived far from polluted area of 12 km.The follow up investigation included age,sexuality,family economic situation,time of use or stop use of arsenic coal, ventilation of the room,desiccation of food etc.Diethyl dithiocarbamate silver(Ag-DDC)method was used to detect arsenic content of coal,soil,air,water and rice,corn,chili;Single factor and multivariate factors non-conditional Logistic regression models were used to analyze exposure factors of patients and related environmental risk factom, and the differences of those in 1998 and 2006 were compared. Results The arsenic content in indoor and outdoor air,coal,chili and corn went down from 0.0880 and 0.0220 mg/m3,397.20,45.07 and 2.64 mg/kg in 1998 to 0.0790 and 0.0070 mg/m3,93.01,3.46 and 1.50 mg/kg in 2006. Arsenic contents of other samples were less than national standard. The analysis of single factor and multivariate factors non-conditional Logistic regression showed that time of using high arsenic coal,age,fluorosis and smoking(x2 = 50.159,12.195,37.69,6.358,P ＜ 0.05 or ＜ 0.01 ) were still the main risk factors for arsenism,while family economic situation was still influential factors (X2 = 4.614,P ＜ 0.05);Ventilation of the room changed from a risk factors at 1998 to an influencing factors at 2006(X2 = 38.093,P ＜ 0.01 ). Single factor non-conditional Logistic regression model analysis showed that food desiccation by arsenic coal-burning and educational level were no longer risk and influencing factors,while food preservation and gender had become influencing factors(x2 = 17.463,11.004,all P ＜ 0.01 ) nine years after. Conclusions Environmental arsenic pollution in arsenism area in Guizhou Province has been obviously improved after nine years. However,the continued existence of low doses of arsenic pollution is still a major cause of failure of controlling arsenism. Time of using high arsenic coal,age,smoking,fluorosis,family economic situation and ventilating room are closely related to the occurrence and the development of arsenism. Prohibition of use of high arsenic coal,furnace improvement,health education and economic development are effective measures

Relationship between myeloperoxidase and catalase genetic polymorphism and their activities with arsenic poisoning caused by coal-burning / 中国地方病学杂志

Objective To detect genetic polymorphism of myeloperoxidase (MPO) gene and catalase (CAT) gene and their activities, and to analyze their relationship with arsenic poisoning caused by coal-burning. Methods One hundred and thirty arsenic poisoning patients were chosen as case group in Jiaole Village, Xingren County, Guizhou Province(an endemic area). One hundred and forty healthy residents living in 13 km away were chosen as control group. Their blood was collected. Polymerase chain reaction-restriction fragment length polymorphism technique(PCR-RFLP) was used to detect polymorphism of MPO-463G/A and CAT-262C/T. Ultraviolet spectmphotometer method was used to detect myeloperoxidase activity. Chromatometry method was used to detect catalase activity. Results The genotype frequency of MPO-463G/A at GG, GA, AA site was 47.24%(60/127), 44.09%(56/127),8.67% (11/127) in case group and 42.34% (58/137),48.17% (66/137)1,9.49% (13/137) in control group, respectively. The difference between the two groups was not significant(χ2 = 0.642, P > 0.05). The genotype frequency of CAT-262C/T, at CC, CT, TT site was 65.60%(82/125),28.80%(36/125),5.60%(7/125) in case group and 76.51%(101/132), 18.94% (25/132) ,4.55% (6/132) in control group, respectively, without significant difference (χ2 =3.845, P>0.05). The relationship between polymorphism of MPO-463G/A and CAT-262C/T and the risk of arsenic poisoning was not found in this study(ORadj= 1.36, 95%CI: 0.74-2.50 for MPO; ORadj=1.35, 95%CI: 0.69-2.63 for CAT). The activities of MPO and CAT were (25.30±8.70)U/L and (2.80± 1.09)×103 U/L in case group, while (22.76±7.59)U/L and (3.90±1.01)×103U/L in control group with a significant difference(F=0.760 for MPO, F=0.855 for CAT, all P < 0.05). The genotype of MPO-463G/A and CAT-262C/T was not found to have relationship with the activities of MPO, CAT(F=1.312,2.822 for MPO; F= 0.151,0.036 for CAT, P>0.05). Conclusions Genetic polymorphism of MPO-463G/A and CAT-262C/T is not found to have relationship with arsenic poisoning. Arsenic can lead to the change of MPO and CAT activity, which, however, may not be affected by MPO-463G/A and CAT-262C/T polymorphism.

Application of benchmark dose on the study of people's liver dysfunction induced by arsenic-coal burning and its significance / 中国地方病学杂志

Objective To explore the biological exposure limit of liver dysfunction induced by arsenic-coal burning, and screen sensitive biornarkers for its' liver dysfunction monitoring. Methods One hundred and eighteen subjects from the exposed area and 50 control from non-pollution area were studied. Their urinary and hair contents of arsenic were tested as exposure biomarkers by Ag-DDC assay. Total bile acid(TBA, detected by enzymatic cycling method), glutathione S-transferase (GSTs, detected by chemical colorimetry) and γ-glutamyl transpeptidase (γ-GT, detected by colorimetry of diazotization reagent) were used as biomarkers indicating liver cell damage. were used as liver fibrosis biomarkers. The benchmark dose (BMD) and the lower confidence limit of benchmark dose(BMDL) of urinary and hair arsenic were calculated. Sensitivity of each biomarker was estimated according to the BMD and BMDL value. Results The geometric mean of urinary and hair arsenic(98.50 mg/kg Cr, 7.42 mg/kg) μg/L) in the exposed group were significantly higher than urinary and hair arsenic (22.98 mg/kg Cr, 1.28 mg/kg) and each biomarker in the control group(4.63 μmol/L, 13.76 U/L,36.45 U/L,54.62 μg/L,74.45 μg/L,54.81 μg/L, P<0.01). Significant dose-effect relationship existed between urinary and hair arsenic contents and each biomarker. BMD and BMDL value of urinary arsenic was 49.53-101.96 mg/kg Cr and 39.02-70.15 mg/kg Cr, respectively. Those of hair arsenic were 3.04-5.02 mg/kg and 2.36-3.25 mg/kg, respectively. According to BMD and BMDL value of urinary and hair arsenic, the sensitivity of biomarkers decreased in the order of GSTs, TBA and Conclusions According to the lowest BMD and BMDL of urinary and hair arsenic, averaged reference value of urinary and hair arsenic in the local normal population, we suggest urinary 35.0 mg/kg Cr and hair 2.5 mg/kg as their biological exposure limits for those with liver dysfunction induced by arsenic-coal burning. GSTs, TBA, γ-GT and HA, Ⅳ. C, PC-Ⅲ can respectively reflect liver cell damage and liver fibrosis caused by arsenic-coal burning in different degrees, among which, GSTs and HA are the most sensitive biomarkers respectively for liver cell damage and liver fibrosis.

Influence of coal-arsenic exposure on human T cells proliferation and its mechanism / 中国地方病学杂志

Objective To explore the influence of coal-arsenic exposure on human T cells proliferation and its mechanism.Methods Blood samples colleoted from individuals which lived in arsenism area of coal-burning type and non-arsenism area in Guizhou Province were divided into exposed group(17),mild(35),moderate(38) and severe arsenism group(19)and control group(35)according to Diagnosis Smndard for Endemic Arsenism (WS/T 211-2001).T cell stimulation index wag determined by methyl thiazolyl tetrazolium(MTT)colorimetric method.The intracellular Ca2+ exponential(IECa2+)in peripheral blood mononuclear cell(PBMC)was analyzed by Fho-3/AM dye and flow cytometry.DNA binding activity of actively T cells nuclear factor(NF-AT)in PBMC was evaluated by electrophoretie mobility shift assay(EMSA).Results Concanavalin A(ConA)stimulation decreased the T cells stimulation indexes in exposed group,mild,moderate and severe arsenism groups(1.315±0.962, 1.611±1.224,1.114±0.545,1.289±0.875)compared with control group(2.322±1.241),all the differences being statistically significant(P＜0.01).After stimulated by anti-CD3 monoclonal antibody(McAb),the T cells stimulation index in exposed group,mild,moderate and severe arsenism group(0.997±0.177,1.103±0.291,1.007±0.221, 0.957±0.205) were lower than that of control group(1.842±0.429,P ＜ 0.01 ). IECa2+ of PBMC after treated by anti-CD3 McAb in mild,moderate and severe arsenism group( 110.130±49.637,92.429±31.191,77.640± 35.372) were lower compared with control group(145.986±59.450,P ＜0.01 ). Moreover,IECa2+ in moderat and severe arsenism group were lower than exposed group(121.337±46.410,P ＜ 0.05). DNA binding activity of PBMC NF-AT in mild,moderate and severe arsenism group(1.354±0.446,1.290±0.291,1.159±0.411 ) were lowered than that of control group(1.722±0.291,P ＜ 0.01) and exposed group(1.611±0.294,P ＜ 0.05). Conclusions The coal-arsenic exposure can reduce the human T cells stimulation indexes,IECa2+ in PBMC and the DNA binding activity of NF-AT. It suggest that arsenic may suppress the proliferation ability of human T cells,which may be partly related to the influence of arsenic on T cell receptor(TCR)/CD3 signal transduetion pathway.