Blood Pressure Associated with Arsenic Methylation and Arsenic Metabolism Caused by Chronic Exposure to Arsenic in Tube Well Water

Objective The effects of arsenic exposure from drinking water, arsenic metabolism, and arsenic methylation on blood pressure（BP） were observed in this study. Methods The BP and arsenic species of 560 participants were determined. Logistic regression analysis was applied to estimate the odds ratios of BP associated with arsenic metabolites and arsenic methylation capability. Results BP was positively associated with cumulative arsenic exposure（CAE）. Subjects with abnormal diastolic blood pressure（DBP）, systolic blood pressure（SBP）, and pulse pressure（PP） usually had higher urinary i As（inorganic arsenic）, MMA（monomethylated arsenic）, DMA（dimethylated arsenic）, and TAs（total arsenic） than subjects with normal DBP, SBP, and PP. The i As%, MMA%, and DMA% differed slightly between subjects with abnormal BP and those with normal BP. The PMI and SMI were slightly higher in subjects with abnormal PP than in those with normal PP. Conclusion Our findings suggest that higher CAE may elevate BP. Males may have a higher risk of abnormal DBP, whereas females have a higher risk of abnormal SBP and PP. Higher urinary i As may increase the risk of abnormal BP. Lower PMI may elevate the BP. However, higher SMI may increase the DBP and SBP, and lower SMI may elevate the PP.

Association of Methionine Synthase rs1805087 Polymorphism With Arsenic-Related Skin Pigmentary Changes:A Population-Based Case-Control Study

Objective:Chronic arsenic exposure causes skin lesions including skin cancers,pigmentary changes,and keratosis.Genetic polymorphism in arsenic metabolism may increase susceptibility to the development of arsenic-related skin lesions.This study was performed to determine whether arsenic metabolism-related gene variants are associated with arsenic-related pigmentary changes.Methods:This case-control study involved 189 patients with arsenic-related pigmentary changes and 103 controls.Thirty-eight polymorphisms in 10 genes determined by mass spectrometry assay served as candidate drivers of arsenic-induced pigmentary changes.Urine and plasma arsenic levels were determined by inductively coupled plasma mass spectrometry.Hair arsenic concentrations were measured by nondispersive atomic fluorescence spectrometry.Arsenic metabolites in urine were determined using high-performance liquid chromatography with inductively coupled plasma mass spectrometry.Serum folate was measured using a folate radio assay kit.Analysis of variance,nonparametric test,or the chi-square test was selected according to the data distribution.Spearman correlation analysis was used to determine the correlation between two parameters.Logistic regression was used to estimate the effect of single-nucleotide polymorphisms.Results:The arsenic concentrations in urine,plasma,and hair and the urine arsenic species were not significantly different between patients and controls.Logistic regression revealed that among the polymorphisms,the methionine synthase(MTR)rs1805087 polymorphism showed a protective effect against arsenic-related pigmentary changes.In the codominant model,the adjusted odds ratio for age,sex,and ethnicity was 0.41(95%confidence interval[CI],0.21-0.80;P=0.008)for the AG genotype and 0.11(95%CI,0.02-0.60;P=0.012)for the GG genotype.Conclusion:MTR polymorphism showed a protective effect against arsenic-related pigmentary changes in the logistic regression model.The effect of MTR rs1805087 might be independent of arsenic metabolism and one-carbon metabolism.More studies are needed to clarify the biological function of MTR rs1805087 and its relationship with the etiology of arsenic-related pigmentary changes.

Arsenobetaine and thio-arsenic species in marine macroalgae and herbivorous animals: Accumulated through trophic transfer or produced in situ?

Arsenobetaine（AB） and thio-arsenoribosides were measured in common macroalgae species（8 phaeophyta, 4 rhodophyta and 2 chlorphyta）, along the Australian south east coast line. As well, arsenic species profiles were measured for two common marine herbivores, the sea urchin Centrostephanus rodgersii and the fish Odax cyanomelas that graze on these macroalgae to understand if trophic transfer of these species would account for their presence in marine herbivores. AB was found in seven of the fourteen macroalgae species investigated but does not contributed significantly to any of the macroalgae arsenic content（0.01-1.2 μg/g）. AB was found in only two of the brown macroalgae and all the red and green macroalgae（with the exception of Corallina officinalis）. Thio-arsenic species were found sporadically, but not in high concentrations in any of the macroalgae investigated.AB present in macroalgae is likely to be associated with epiphytic organisms while thio-arsenoribosides are likely to be produced by decaying parts of damaged macroalgae.A laboratory feeding experiment in which the herbivorous gastropod, Austrocochlea constricta, was fed macroalgae containing thio-arsenoribosides for a 24 hr period every three days showed that these are readily accumulated over a short period. Thio-arsenoribosides in herbivores are therefore probably obtained through trophic transfer. Some AB is also obtained through trophic transfer; however, the presence of trimethylated arsonioribosides,a hypothesized precursor of AB formation in herbivores, suggests that some AB is produced within herbivores from the transformation of arsenoribosides accumulated from their diet.

Single nucleotide polymorphism rs11191454 in arsenite methyltransferase is associated with flow in Chinese students:a genetic study on flow experience

Flow has been widely studied in the field of positive psychology.However,little is known regarding its biological mechanism.This study aimed to ascertain flow-related gene loci.We investigated the association between flow and five single nucleotide polymorphisms associated with common mental disorders among a sample of 870 healthy 1 st year students of Jining Medical University,Shandong Province,China.This study was approved by the Ethics Committee of Jining Medical University(approval number:JNMC-2016-KY-001)on June 1,2016.rs11191454 demonstrated significant statistical association with flow after adjusting for age and gender(P=0.004).The allele carriers achieved higher scores in all 4 dimensions of flow:merging of action and awareness,challenge-skill balance,sense of control,and clear goals.This biological research article indicates that rs11191454 in the arsenite methyltransferase(AS3MT)gene might be associated with flow in a Chinese Han population,and that might result from altered arsenic metabolism.