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Objective:To explore the effects of Ginkgo biloba on regulating NF-E2-related factor 2 (Nrf2)-Kelch-like ECH-associated protein 1 (Keap1)-antioxidant response element (ARE) signaling pathway in liver injury induced by coal-burning-borne endemic arsenic poisoning in rats.Methods:Group design method was adopted, according to body weight (80-100 g), a total of 30 Wistar rats were divided into 5 groups (6 rats in each group, half males and half females) by random number table method. The normal control group was fed with normal diet ad libitum for 4.5 months; the Ginkgo biloba control group was fed with Ginkgo biloba (25 mg/kg, 6 d/week) for 1.5 months after normal feeding for 3 months; the drinking water arsenic poisoning group and the arsenic contaminated grain group were fed respectively with 100 mg/L arsenic trioxide (As 2O 3) solution and 100 mg/kg arsenic-containing feed for 3 months, and then fed with normal diet for 1.5 months; the Ginkgo biloba treatment group was fed with 100 mg/kg arsenic-containing feed for 3 months, and then was given Ginkgo biloba (25 mg/kg, 6 d/week) for 1.5 months. After sacrificing the animals, the content of malondialdehyde (MDA), the activity of copper zinc superoxide dismutase (SOD1) and the activity of glutathione peroxidase (GPx) in serum were detected by thiobarbituric acid colorimetry, xanthine oxidase method and dimercaptodinitrobenzoic acid reduction method, respectively. The mRNA and protein expressions of indicator genes of Nrf2-Keap1-ARE signaling pathway in liver tissues were detected by quantitative real-time PCR, immunohistochemistry and Western blotting. Correlation between the indexes was analyzed by Pearson. Results:In drinking water arsenic poisoning group, arsenic contaminated grain group and Ginkgo biloba treatment group, the contents of MDA in serum were (3.54±0.51), (3.83±0.87) and (2.93±0.84) μmol/L, respectively, which were higher than that in normal control group [(1.85±0.36) μmol/L, P < 0.05]; and SOD1 activities [(68.21±4.37), (64.53±9.96), (73.09±5.43) U/ml] and GPx activities [(486.41±40.45), (458.24±42.25), (539.79±79.43) U/L] in serum were lower than those in normal control group [(81.47±5.73) U/ml, (747.86±80.33) U/L, P < 0.05]. Compared with the arsenic contaminated grain group, the content of MDA in serum in Ginkgo biloba treatment group was decreased, the activities of SOD1 and GPx in serum were increased ( P < 0.05). Compared with normal control group, the mRNA expressions of SOD1 and GPx1 in the liver tissues in drinking water arsenic poisoning group, arsenic contaminated grain group and Ginkgo biloba treatment group were significantly higher ( P < 0.05). Compared with arsenic contaminated grain group, the mRNA expressions of SOD1 and GPx1 in the liver tissue in Ginkgo biloba treatment group were increased ( P < 0.05). Compared with the normal control group, the protein expression of SOD1 in liver tissue in arsenic contaminated grain group was decreased ( P < 0.05), the protein expressions of GPx1 were decreased in the liver tissues in drinking water arsenic poisoning group, arsenic contaminated grain group and Ginkgo biloba treatment group ( P < 0.05). Compared with the arsenic contaminated grain group, the protein expressions of SOD1 and GPx1 were increased in the liver tissue in Ginkgo biloba treatment group ( P < 0.05). Compared with the normal control group and arsenic contaminated grain group, the protein expression of Keap1 was decreased in the liver tissue in Ginkgo biloba treatment group ( P < 0.05). Compared with the normal control group, the protein expressions of Nrf2 and phosphorylation of Nrf2 (pNrf2) were increased in the cytoplasm in drinking water arsenic poisoning group, arsenic contaminated grain group and Ginkgo biloba treatment group ( P < 0.05). Compared with the arsenic contaminated grain group, the protein expression of pNrf2 was decreased in the cytoplasm in Ginkgo biloba treatment group ( P < 0.05). The protein expressions of Nrf2 and pNrf2 in the nucleus in drinking water arsenic poisoning group, arsenic contaminated grain group and Ginkgo biloba treatment group were also higher than those in normal control group ( P < 0.05). Compared with the arsenic contaminated grain group, the protein expressions of Nrf2 and pNrf2 were increased in the nucleus in Ginkgo biloba treatment group ( P < 0.05). The results of correlation analysis revealed that the protein expressions of Nrf2 and pNrf2 in the nucleus were negatively correlated with Keap1 protein expression ( r=-0.523,-0.401, P < 0.05), and positively correlated with the mRNA expressions of SOD1 and GPx1 ( r=0.658, 0.530, 0.555, 0.603, P < 0.05). In addition, the protein expressions of SOD1 and GPx1 were positively correlated with their enzyme activities ( r=0.472, 0.629, P < 0.05). Conclusions:Arsenic could induce oxidative stress and liver injury. Ginkgo biloba could reduce the protein expression of Keap1, and promote nuclear translocation of Nrf2, which might induce the up-regulation of mRNA expressions of SOD1 and GPx1, and partially reverse the posttranscriptional regulation of arsenic on SOD1 and GPx1, and then increase their protein expressions and enzyme activities, thereby improve arsenic induced oxidative stress and liver injury.
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Objective:To understand the overall health status of residents in coal-burning-borne arsenic poisoning areas in Yuzhang Town, Xingren City, Guizhou Province after the implementation of comprehensive prevention and control measures, and to provide references for formulating endemic arsenic poisoning prevention strategies in the new era.Methods:Yuzhang Town, Xingren City of Qianxinan Autonomous Prefecture, Guizhou Province was selected as the survey site. According to the "Standards for Determination and Classification of Endemic Arsenic Poisoning Areas"(WS 277-2007), eleven administrative villages in Yuzhang Town were divided into 5 arsenic-exposed villages and 6 non-arsenic-exposed villages. The basic population data of each administrative village were collected, and the changes of mortality rate, standardized mortality rate, average age of death and life expectancy of residents in the whole town, arsenic-exposed villages and non-arsenic-exposed villages from 2006 to 2018 were calculated and analyzed.Results:From 2006 to 2018, the average annual mortality in arsenic-exposed villages was 597.28/100 000 (756.62/100 000 for males and 432.91/100 000 for females), which was higher than that in non-arsenic-exposed villages (503.79/100 000, 600.82/100 000 for males and 405.02/100 000 for females). Using the overall gender composition of the town as criterion, the standardized mortality rate for arsenic-exposed villages and non-arsenic-exposed villages were 598.79/100 000 and 503.04/100 000, respectively. The population mortality rate in the town showed a downward trend from 2006 to 2018, and the mortality rate of residents in arsenic-exposed villages was higher than that of non-arsenic-exposed villages. The annual mortality rate of males was higher than that of females. From 2006 to 2018, the average age of death in the town increased year by year, from 53.93 years old in 2006 to 67.11 years old in 2018. Among them, the age of death of arsenic-exposed villages was increased from 55.22 years old to 65.17 years old, and non-arsenic-exposed villages increased from 52.64 years old to 68.93 years old. The life expectancy of males, females and total in arsenic-exposed villages (66.29, 75.65, 70.33 years in 2006 and 79.38, 86.39, 83.01 years in 2018) were lower than those in non-arsenic-exposed villages (69.86, 80.77, 74.50 years in 2006 and 83.25, 91.85, 87.25 years in 2018).Conclusion:After the comprehensive prevention and control measures are fully covered in the coal-burning-borne arsenic poisoning area, the health level of the residents in the town is significantly improved, but the long-term health effect, disease distribution, disease burden and other issues of the residents in the arsenic poisoning area are still need to be paid attention to.
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Objective To observe the expression of Protein Kinase C Delta (PKCδ) and NF-E2-related factor 2 (Nrf2) in the liver of arsenic poisoning rats induced by coal-burning,and explore their roles.Methods According to body weight (80-100 g),thirty Wistar rats (half male half female) were divided into five groups of 6 each using random number table method,the control group,and drinking arsenic,low,medium and high arsenic contaminated grain groups.The control group was fed normally for 3 months;drinking arsenic,low,medium and high arsenic contaminated grain groups were fed respectively with 100 mg/L As2O3 solution and different concentrations of arsenic-containing feed (25,50 and 100 mg/kg).At the end of the experiment period,non-anticoagulant whole blood 2 ml from peripheral vein was collected.Malondialdehyde (MDA) contents,activities of superoxide dismutase 1 (SOD1) and glutathione peroxidase (GPx) were detected.After sacrificing the animals,the liver was separated and then diacylglycerol (DAG) contents,mRNA and protein expressions of PKCδ and Nrf2 were determined,and the correlation was analyzed by Pearson.Results There were significant differences in serum MDA contents,SOD1 and GPx activities among groups (F =26.441,3.327,120.645,P ＜ 0.05).The serum MDA contents in arsenic-exposed groups were higher than that of the control group (P ＜ 0.05).However,activities of SOD1 and GPx1 were lower than those in the control group (P ＜ 0.05).There were significant differences in liver DAG contents,Nrf2 mRNA expression levels among groups (F =8.237,8.656,P ＜ 0.05).DAG contents in the liver tissues of the drinking arsenic,low,medium and high arsenic contaminated grain groups were respectively (2.67 ± 0.25),(2.36 ± 0.19),(2.54 ± 0.22) and (2.69 ± 0.32) μg/L,which were significantly higher than that in the control group [(2.05 ± 0.24) μg/L,P ＜ 0.05].The expression levels of Nrf2 mRNA in liver tissue were respectively 1.16 ± 0.09,1.09 ± 1.20,1.14 ± 0.15 and 1.27 ± 0.16,which were higher than that in the control group (0.94 ± 0.08,P ＜ 0.05).There were significant differences in the expression of pPKCδ protein in the cell membrane and cytoplasm of liver tissue between groups (F =15.925,6.699,P ＜ 0.05).The protein expression levels of pPKCδ in the cell membrane of liver tissue were 0.49 ± 0.06,0.33 ± 0.05,0.37 ± 0.06 and 0.50 ± 0.08,respectively,which were significantly higher than that in the control group (0.28 ± 0.04,P ＜ 0.05).The protein expression levels of pPKCδ in the cytoplasm were 0.38 ± 0.06,0.31 ± 0.05,0.35 ± 0.05 and 0.36 ± 0.05,respectively,which were higher than that in the control group (0.24 ± 0.05,P ＜ 0.05).There were significant differences in the expression of Nrf2 and pNrf2 in cytoplasm and nucleus of liver tissues among groups (F =9.024,9.709,10.396,25.532,P ＜ 0.05).The protein expression levels of Nrf2 in the cytoplasm were respectively 0.76 ± 0.09,0.58 ± 0.07,0.64 ± 0.09 and 0.73 ± 0.07,which were higher than that of the control group (0.52 ± 0.08,P ＜ 0.05),except the low arsenic contaminated grain group.The protein expression levels of pNrf2 in the cytoplasm were respectively 0.50 ± 0.07,0.43 ± 0.06,0.48 ± 0.06 and 0.54 ± 0.07,which were higher than that in the control group (0.32 ± 0.06,P ＜ 0.05).The expression levels of Nrf2 protein in the nucleus were respectively 0.44 ± 0.07,0.41 ± 0.06,0.47 ± 0.06 and 0.54 ± 0.09,which were higher than that in the control group (0.30 ± 0.05,P ＜ 0.05).The protein expression levels of pNrf2 in the nucleus were respectively 0.35 ± 0.04,0.29 ± 0.04,0.41 ± 0.05 and 0.43 ± 0.06,which were higher than that in the control group (0.20 ± 0.03,P ＜ 0.05).The correlation analysis showed that DAG contents and the protein expression of pPKCδ in the cell membrane and the cytoplasm were positively correlated (r =0.663,0.604,P ＜ 0.05).Furthermore,the protein expression of pPKCδ in the cell membrane and pNrf2 in the cytoplasm and nucleus were also positively correlated (r =0.642,0.670,P＜ 0.05).Conclusions Arsenic could induce oxidative stress liver injury,and upregulate the mRNA and protein expression of Nrf2.Moreover,arsenic could also increase the protein expression of pPKCδ and DAG content,and then promote pPKCδ membrane transposition,phosphorylate Nrf2,and induce its nuclear transposition,which could regulate oxidative stress reaction.
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Objective@#To systematically review the correlation between endemic arsenism and liver injury.@*Methods@#Pertinent studies were identified by searching Pubmed, Embase, China National Knowledge Infrastructure (CNKI) and Wanfang Data databases through November 2018. Studies that reported endemic arsenism and liver injury at home and abroad were collected. All of the Meta-analysis were performed by using Review Manager 5.3 software. The odds ratios (OR) and standardized mean differences (SMD) were used to compare continuous and dichotomous variables. The I2 was used to assess heterogeneity among studies, and the fixed-effects model or the random-effects model was chosen for the quantitative analysis. Subgroup analysis were performed to discuss sources of heterogeneity. The publication bias was evaluated by inverted funnel plot.@*Results@#Totally 16 documents were included, including 7 in English and 9 in Chinese. With liver injury (including the results of hepatomegaly epidemic, abnormal Bultrasound or pathological examination of liver, cirrhosis with definite diagnosis, etc.), different serum liver function and liver fibrosis indicators as the outcome, 7 274 cases, 410-820 cases and 255 cases were included in the arsenic exposure group, and 5 078 cases, 134-327 cases and 164 cases in the control group, respectively. The Meta-analysis showed that arsenic exposure was associated with increased risk of liver injury [OR value and 95% confidence interval (CI) was 2.40 (1.43-4.05), Z=3.30, P < 0.01]. Arsenic exposure had promoted the levels of serum aspartate aminotransferase (AST), alkaline phosphatase (ALP), glutamyltransferase (γ-GT) and total bile acid [TBA, SMD and 95%CI were 1.71 (0.18-3.23), 1.73 (0.42-3.03), 0.25 (0.09-0.41) and 0.55 (0.35-0.75), respectively, P < 0.05 or < 0.01], while had suppressed the level of serum albumin [ALB, SMD and 95%CI were-2.37 (-4.01 -- 0.73), P < 0.01]. Among the serum indicators for liver fibrosis, the levels of serum procollagen type Ⅲ (PC-Ⅲ) and collagen type Ⅳ(Ⅳ-C) were significantly increased in arsenic exposed patients [SMD and 95%CI were 0.98 (0.05-1.91), 1.60 (1.38-1.83), respectively, P < 0.05 or < 0.01]. Subgroup analysis showed that arsenic exposure had been stopped or not at the time of study, study design (including cross-sectional study and cohort study) had a significant effect on the association between arsenic exposure and liver injury (χ2=17.17, 11.85, P < 0.01).@*Conclusions@#Both drinking water-borne arsenicosis and coal burning-borne arsenicosis can cause high incidence of liver injury. ALP, ALB, γ-GT and TBA can be used as serum biomarkers for arsenic exposure induced liver injury. After blocking of arsenic exposure by adopting comprehensive prevention and control measures such as changing water sources and installation of ventilated stoves, the liver injury of patients could be effectively improved.
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Objective To systematically review the correlation between endemic arsenism and liver injury. Methods Pertinent studies were identified by searching Pubmed, Embase, China National Knowledge Infrastructure (CNKI) and Wanfang Data databases through November 2018. Studies that reported endemic arsenism and liver injury at home and abroad were collected. All of the Meta-analysis were performed by using Review Manager 5.3 software. The odds ratios (OR) and standardized mean differences (SMD) were used to compare continuous and dichotomous variables. The I2 was used to assess heterogeneity among studies, and the fixed-effects model or the random-effects model was chosen for the quantitative analysis. Subgroup analysis were performed to discuss sources of heterogeneity. The publication bias was evaluated by inverted funnel plot. Results Totally 16 documents were included, including 7 in English and 9 in Chinese. With liver injury (including the results of hepatomegaly epidemic, abnormal B -ultrasound or pathological examination of liver, cirrhosis with definite diagnosis, etc.), different serum liver function and liver fibrosis indicators as the outcome, 7274 cases, 410 - 820 cases and 255 cases were included in the arsenic exposure group, and 5078 cases, 134 - 327 cases and 164 cases in the control group, respectively. The Meta-analysis showed that arsenic exposure was associated with increased risk of liver injury [OR value and 95％ confidence interval (CI) was 2.40 (1.43 - 4.05), Z = 3.30, P < 0.01]. Arsenic exposure had promoted the levels of serum aspartate aminotransferase (AST), alkaline phosphatase (ALP), glutamyltransferase (γ-GT) and total bile acid [TBA, SMD and 95％CI were 1.71 (0.18 - 3.23), 1.73 (0.42 - 3.03), 0.25 (0.09 - 0.41) and 0.55 (0.35 - 0.75), respectively, P < 0.05 or < 0.01], while had suppressed the level of serum albumin [ALB, SMD and 95％CI were - 2.37 ( - 4.01 - - 0.73), P < 0.01]. Among the serum indicators for liver fibrosis, the levels of serum procollagen type Ⅲ (PC-Ⅲ) and collagen type Ⅳ (Ⅳ-C) were significantly increased in arsenic exposed patients [SMD and 95％CI were 0.98 (0.05 - 1.91), 1.60 (1.38 - 1.83), respectively, P < 0.05 or < 0.01]. Subgroup analysis showed that arsenic exposure had been stopped or not at the time of study, study design (including cross-sectional study and cohort study) had a significant effect on the association between arsenic exposure and liver injury (χ2 = 17.17, 11.85, P < 0.01). Conclusions Both drinking water-borne arsenicosis and coal burning-borne arsenicosis can cause high incidence of liver injury. ALP, ALB, γ-GT and TBA can be used as serum biomarkers for arsenic exposure induced liver injury. After blocking of arsenic exposure by adopting comprehensive prevention and control measures such as changing water sources and installation of ventilated stoves, the liver injury of patients could be effectively improved.
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Objective To detect the mRNA and protein expression of downstream quinine nicotinamide adenine dinucleotide (NADH) dehydrogenase 1 (NQO1) and heme oxygenase 1 (HO-1) induced by blood nuclearrelated factor E2 (Nrf2) in the peripheral blood of those exposed to arsenic in the endemic area of coal arsenic poisoning in Guizhou Province,and to discuss its role in the process of occurrence and development of liver injury due to coal arsenic poisoning.Methods Jiaole and Changqing villages in coal-burning-borne arsenism areas in Xingren County of Guizhou were selected as the survey sites,and 161 cases of arsenic-exposed residents were selected as the arsenic exposed group based on physical examination.They were divided into non-patient group (21 cases) and patient group (140 cases) according to the Diagnostic Criteria of Endemic Arsenism (WS/T 211-2001),and the patient group was further divided into mild hepatosis group (52 cases),moderately severe hepatosis group (36 cases) and non-apparent hepatosis group (52 cases) according to the Diagnostic Criteria of Occupational Chronic (GBZ 59-2010).Moreover,45 residents from one village neighboring to non-epidemic area were selected as controls.Peripheral blood samples were collected from all subjects.And mRNA expression of NQO1 and HO-1 were detected by RT-qPCR.Content of NQQ1 and HO-1 were detected by enzyme linked immunosorbent assay (ELISA).Results (①)Results of mRNA expression of NQ01 and HO-1:the relative expression level of mRNA of NQO1 and HO-1 in peripheral blood went up gradually as the degree of liver injury of population exposed to arsenic increased (F =5.548,10.961,all P ＜ 0.05);thereinto,the relative expression level of mRNA of NQO1 of mild hepatosis group (median:0.918) was higher than that of the control group (0.576,P ＜ 0.05),the relative expression level of mRNA of NQO1 of moderately severe hepatosis group (1.243) was higher than those of control group,non-patient group (0.653),non-apparent hepatosis group (0.636) and mild hepatosis group (all P ＜ 0.05);the relative expression level of mRNA of HO-1 of non-patient group (1.059),non-apparent hepatosis group (1.225),mild hepatosis group (1.553) and moderately severe hepatosis group (1.604) were higher than that of control group (0.767,all P ＜ 0.05);the relative expression level of mRNA of HO-1 of mild hepatosis group was higher than that of non-patient group (P ＜ 0.05);the relative expression level of mRNA of HO-1 of moderately severe hepatosis group was higher than those of non-patient group and non-apparent hepatosis group (all P ＜ 0.05).②)Results of protein expression of NQO-1 and HO-1:the level of protein expression of NQO1 and HO-1 in serum went up gradually as the degree of liver injury of population exposed to arsenic increased (F =19.685,17.725,all P ＜ 0.05).Thereinto,the protein expression of NQO1 and HO-1 of non-apparent hepatosis group,mild hepatosis group and moderately severe hepatosis group [NQO1:(6.272 ± 0.744),(6.336 ± 0.628),(6.714 ± 0.540) U/L;HO-1:(45.150 ± 4.813),(45.283 ± 5.049),(48.610 ± 5.365) U/L] were higher than those of control group and non-patient group [NQO1:(5.550 ± 0.730),(5.750 ± 0.427) U/L;HO-1:(39.856 ± 5.249),(42.375 ± 3.014) U/L,all P ＜ 0.05],the protein expression of NQO1 and HO-1 of moderately severe hepatosis group were higher than those of non-apparent hepatosis group and mild hepatosis group (all P ＜ 0.05).Conclusion The expression of mRNA and protein of NQO1 and HO-1 is closely related to the occurrence and development of liver injury due to arsenic exposure in coal arsenic poisoning areas.
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Objective To explore the effects and the possible mechanism of Gingko biloba on liver injury due to arsenic poisoning in rats,and to provide experimental evidence for prevention and treatment of arsenic poisoning.Methods The corn powder baked by high arsenic coal was served as the main raw material to make feed containing arsenic.Forty healthy Wistar rats were randomly divided into 5 groups according to their body weights,including control group A,arsenic poisoning group,control group B,natural recovery group and Ginkgo biloba treatment group,eight rats in each group,half male and half female.The control group A rats were fed with normal diet ad libitum for 3.0 months;the arsenic poisoning group rats were freely given feed containing arsenic (100 mg/kg) for 3.0 months;the control group B rats were fed with normal diet ad libitum for 4.5 months;the natural recovery group rats were freely given arsenic (100 mg/kg) feed for 3.0 months,and then given a normal diet for 1.5 months;Ginkgo biloba treatment rats ingested arsenic feed for 3.0 months,and then give Ginkgo biloba solution (25 mg/kg) orally,6 d/week for 1.5 months,then back to normal diet.The content of arsenic in urine,liver,as well as the liver function indices [alanine aminotransferase (ALT),aspartate transaminase (AST),total bile acids (TBA),gamma glutamyl aminopeptidase (GGT),glutathione S-transferase (GSTs)] and the oxidative stress indexes [superoxide dismutase (SOD),glutathione peroxidase (GPx),thiol (-SH),malondialdehyde （MDA)] of liver homogenate,were measured.Results The arsenic content of urine and liver (geometric mean) of the rats in arsenic poisoning group (2 991.24 μg/g Cr,4.29 μg/g) were significantly higher than those in control group A (91.59 μg/g Cr,1.00 μg/g).Urinary arsenic and liver arsenic levels of rats in natural recovery and Ginkgo biloba treatment groups (467.39,334.48 μg/g Cr;,3.15,1.88 μg/g) were higher than those in control group B (99.54 μg/g Cr,0.85 μg/g).The arsenic contents of urine of the rats in natural recovery group,the arsenic contents of urine and liver of rats of Ginkgo biloba treatment group were all lower than those in arsenic poisoning group.The differences were significant (all P ＜ 0.05).The activity/contents of AST,TBA,GGT,GSTs of rats in arsenic poisoning group [(212.88 ± 29.76) U/L,(19.19 ± 4.33) μmol/L,(1.73 ± 0.50) U/L,(196.21 ± 47.38) U/L] were all significantly higher than those in control group A [(142.63 ± 24.20) U/L,(6.23 ± 2.95) μmol/L,(0.77 ± 0.32) U/L,(142.86 ± 28.58) U/L].The activity/contents of TBA,GGT,GSTs in natural recovery group were (17.07 ± 3.92) μ,mol/L,(1.47 ± 0.57) U/L and (178.06 ± 27.37) U/L;and the contents of TBA in Ginkgo biloba treatment group were (13.60 ± 3.00) μmol/L;which were all higher than those in control group B [(7.55 ± 2.45) μmol/L,(0.74 ± 0.51) U/L,(145.17 ± 28.59) U/L].The activity of AST in natural recovery group [(137.44 ± 23.20) U/L],the activity/contents of AST,TBA,GGT and GSTs in Ginkgo biloba treatment group[(129.63 ± 31.25) U/L,(13.60 ± 3.00) μmol/L,(1.15 ± 0.48) U/L,(155.64 ± 20.79) U/L,respectively] were all lower than those in arsenic poisoning group.The content of TBA in Ginkgo biloba treatment group was lower than that of natural recovery group.The differences of those indexes were all significant (all P ＜ 0.05).The activity/contents of SOD,GPx and-SH in arsenic poisoning group [(46.34 ± 11.39),(275.16 ± 92.00) U/mg prot and (0.08 ± 0.02) μmol/mg prot] were all significantly lower than those in control group A [(75.52 ± 8.72),(1 351.01 ± 395.96) U/mg prot,(0.13 ± 0.01) μmol/mg prot].The activity of SOD and GPx in natural recovery group [(42.44 ± 9.58),(694.87 ± 187.01) U/mg prot] were all lower than those in control group B [(68.17 ± 11.11),(1 342.80 ± 185.04) U/mg prot].The activity of GPx in natural recovery group,the activity/contents of SOD,GPx,-SH in Ginkgo biloba treatment group [(63.90 ± 10.44),(1 283.28 ± 373.87) U/mg prot,(0.12-± 0.02) μmol/mg prot] were all higher than those in arsenic poisoning group.The contents of SOD,GPx,-SH in Ginkgo biloba treatment group were higher than those of natural recovery group.The content of MDA in arsenic poisoning group [(3.05 ± 0.94) nmol/mg prot] was higher than that in control group A [(1.67 ± 0.55) nmol/mg prot].The content of MDA of rats in natural recovery and Ginkgo biloba treatment groups were (2.22 ± 0.93),(1.77 ± 0.37) nmol/mg prot,which were lower than those in the arsenic poisoning group.The differences of the above indexes were all significant (all P ＜ 0.05).Conclusion Ginkgo biloba can reduce the accumulation of arsenic in the liver and ameliorate lipid peroxidation,relieve liver injury effectively in rats caused by coal-burning arsenic.
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Objective To study the expression and enzyme activity of thioredoxin reductase 1 (TrxR1) in liver and peripheral blood of human and rats exposed to airborne arsenic through coal-burning as well as its role in liver injury of coal-burning-borne arsenic poisoning.Methods This study was divided into 2 parts.Part 1 was a population study:133 local residents exposed to airborne arsenic through coal-burning were selected as arsenic exposure groups including a non-patient group (25 cases),no obvious hepatopathy group (38 cases),mild (43 cases) and moderate to severe hepatopathy groups (27 cases) from areas affected by endemic arsenism in Guizhou Province.Thirty-four healthy residents from arsenic not affected areas were selected as controls.Peripheral blood samples were collected from all these people.The expression of TrxR1 mRNA was determined by real-time fluorescence quantitative PCR (qPCR),and enzyme activity of TrxR was tested by visible spectrophotometry.Part 2 was an animal experiment study:Thirty Wistar rats,weighing about 80-100 g,were divided into control group,drinking-waterborne arsenic poisoning group and coal-burning-borne arsenic poisoning group (including low,medium and high arsenic contaminated grain groups) by means of a table of random number according to body mass,6 rats in each group.The control group was fed with normal diet for 3 months; drinking-water-borne arsenic poisoning group and coal-burning-borne arsenic poisoning group were fed with 10 mg/kg As2O3 solution and different concentrations(25,50,100 mg/kg) of arsenic-containing feed,respectively,for 3 months.The expression of TrxR1 mRNA was determined by qPCR; protein expression level of TrxR1 in liver tissue was detected by immunohistochemistry,and enzyme activity of TrxR in serum and liver tissue was tested by visible spectrophotometry.Results The mRNA expressions of TrxR1 in peripheral blood were 1.599 8 (1.128 9-2.156 8),1.469 3 (1.146 1-1.976 3),1.203 6 (0.463 1-1.816 2) and 0.912 3(0.631 8-1.535 0),respectively,among non-patient group,no obvious hepatopathy group,mild and moderate to severe hepatopathy groups.Compared to the control group[1.649 7(1.161 1-2.380 2)],the differences were significant statistically in mild and moderate to severe hepatopathy groups (all P ＜ 0.05).The enzyme activity of TrxR in peripheral blood was (3.12 ± 0.76),(2.81 ± 0.84),(2.52 ± 0.73),(2.42 ± 0.76)U/ml,respectively,in those corresponding groups.Compared to the control group [(3.02 ± 0.70)U/ml],the differences were significant statistically in mild and moderate to severe hepatopathy groups (all P ＜ 0.05).The mRNA expressions of TrxR1 in peripheral blood were 1.05 ± 0.14,1.18 ± 0.18,1.04 ± 0.10 and 0.97 ± 0.13,respectively,among drinking-water-borne arsenic poisoning group,low,medium and high arsenic contaminated grain groups; all of which were lower than that in the control group (1.23 ± 0.15,all P ＜ 0.05) except that of the low arsenic contaminated grain group.The mRNA expressions of TrxR1 in liver tissue were 0.78± 0.10,0.83 ± 0.10,0.79 ± 0.09 and 0.77 ± 0.11,respectively; all of which were lower than that in the control group (0.94 ± 0.12,all P ＜ 0.05).The protein expression of TrxR1 in liver tissue was 310.33 ± 38.81,312.50 ± 23.36,305.67 ± 20.57 and 298.17 ± 23.52,respectively,among the arsenic poisoning groups; all of which were lower than that in the control group (348.50 ± 32.35,all P ＜ 0.05).The enzyme activity of TrxR in serum was (4.22 ± 0.73),(4.86 ± 0.63),(4.04 ± 0.57),(3.73 ± 0.64)U/ml,respectively; all of which were lower than that in the control group [(9.52 ± 1.08)U/ml,all P ＜ 0.05].The enzyme activity of TrxR in liver tissue was (14.82 ± 1.67),(18.76 ± 2.76),(14.90 ± 2.17),(11.55 ± 1.74) U/mg,respectively; all of which were lower than that in the control group [(23.71 ± 3.05)U/mg,all P ＜ 0.05].Conclusion Arsenic aggravates liver injury of coal-burning arsenic poisoning through down-regulating the expressions of TrxR1 mRNA and protein and reducing its enzyme activity as well.
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OBJECTIVE Study the kidney toxic effects caused by burning coal endemic arsenism in rats,application bench mark dose (BMD) method to investigate the bench mark dose of urinary arsenic (UAs)and the changes in bio markers of renal function.METHODS Wistar rats were fed for 90 d with arsenic 0,25,50,100 mg·kg -1 conta minated feed.Urinary arsenic,kidney arsenic and renal function indicators were determined,and routine pathological and fibrosis of kidney were exa mined.UAs as the exposure bio marker,Uβ2-MG,UNAG and UALB for the effect bio markers,application bench mark dose method to calculate the BMD and BMDL of UAs for each effect bio markers.RESULTS UAs,KAs, Uβ2-MG,UNAG,UALB levels of rats in arsenic 100 mg·kg -1 group were increased than normal group (P <0.05);In light microscope,the results of HE staining of rat kidney in all arsenic dose groups showed infla mmatory cell infiltration,renal tubular epithelial cell swelling,renal interstitial capillary dila-tion,congestion and other varying degrees pathological changes,and the results of masson staining showed varying degrees of tubulointerstitial fibrosis;UAs as the exposure bio marker,Uβ2-MG,UNAG, UALB for the effects of mark,the BMD and BMDL of UAs for Uβ2-MG,UNAG,UALB were calculated, the BMD values were 998.9,1213.5,1386.9 μg·g -1 Cr,the BMDL values were 660.5,803.6 and 909. 4 μg·g -1 Cr,respectively.CONCLUSION Burning coal arsenic pollution can cause kidney da mage in rats,mini mal change nephropathy may be the pri mary pathological in the coal arsenic conta mination of kidney da mage.The BMD and BMDL of UAs were 998.9,660.5 μg·g -1 Cr,the early changes of renal function of burning coal arsenism in rats;it is reco mmended to use the more sensitive bio markers Uβ2-MG to calculate the biological exposure li mits on renal injury caused by arsenic.
