Title: Nutritional Influences on One-Carbon Metabolism: Effects on Arsenic Methylation and Toxicity.

Authors: Bozack, Anne K; Saxena, Roheeni; Gamble, Mary V

Published In Annu Rev Nutr, (2018 08 21)

Abstract: Exposure to inorganic arsenic (InAs) via drinking water and/or food is a considerable worldwide problem. Methylation of InAs generates monomethyl (MMAsIII+V)- and dimethyl (DMAsIII+V)-arsenical species in a process that facilitates urinary As elimination; however, MMAs is considerably more toxic than either InAs or DMAs. Emerging evidence suggests that incomplete methylation of As to DMAs, resulting in increased MMAs, is associated with increased risk for a host of As-related health outcomes. The biochemical pathway that provides methyl groups for As methylation, one-carbon metabolism (OCM), is influenced by folate and other micronutrients, including choline and betaine. Individuals and species differ widely in their ability to methylate As. A growing body of research, including cell-culture, animal-model, and epidemiological studies, has demonstrated the role of OCM-related micronutrients in As methylation. This review examines the evidence that nutritional status and nutritional interventions can influence the metabolism and toxicity of As, with a primary focus on folate.

PubMed ID: 29799766

MeSH Terms: Animals; Arsenic/administration & dosage; Arsenic/metabolism*; Arsenic/toxicity*; Carbon/metabolism*; Dietary Exposure; Humans; Methylation; Nutritional Physiological Phenomena*