Effectiveness of Selenium Supplementation in Combating Cytotoxicity of Arsenic Due to Ingestion of Arsenic from Groundwater in Bangladesh

Selenium supplements are being given to patients in our clinical trial to combat chronic arsenic poisoning resulting from drinking arsenic laced groundwater. A recent study reports that administration of selenium in mammals promote biliary excretion of arsenic. There are evidences from studies in mammals for the in vivo formation and biliary excretion of seleno-bis-(S-glutathionyl)arsinium ion. Glutathione (GSH) plays an important role in the biomethylation of arsenic and biliary excretion of arsenic. The selenoprotein Glutathione Peroxidase (GPx) has been described as the body's frontline anti-oxidation system, and it is believed to be at least partly responsible for the widely reported anti-cancer properties of selenium. Our recent study involving hair analysis from Bangladesh indicates a general deficiency of selenium among the population. The purpose of the current study was to investigate the extent of enhancement in GSH, GPx level in patient serum due to selenium supplementation. The increase of glutathione (GSH) due to selenium supplementation increases the probability of formation of GSH-As-Se complex and elimination of arsenic from the body. In this study we have measured GSH, GPx activity in serum from arsenicosis patients before and after oral administration of supplements. The paper will focus on serum GSH level and GPx activity in a select group of arsenicosis victims in our clinical study cohort. The GSH level and GPx activity significantly increased in arsenicosis patients due to selenium supplementation. Selenium supplementation appears to be an effective agent in increasing GPx activity and combating cytotoxicity of arsenic by increasing blood pool of GSH and elevating GPx activity. Future studies in this regard will include monitoring other selenoproteins in patient serum or whole blood due to selenium supplementation.

Acknowledgements: The work has been supported by a grant from the National Institutes of Health, USA and a grant from Wagner College, New York.