Seth Walk, Ph.D.
Montana State University
Microbes in the gut play an important role in protecting against arsenic toxicity in mice, according to a new NIEHS study. Researchers found that antibiotics disrupted the gut microbiome, allowing more arsenic to accumulate in organs, rather than being excreted. They also found that germ-free mice, which are mice raised without any microorganisms, excreted less and accumulated more arsenic compared to mice with conventional microbiomes.
The researchers also examined mice lacking the enzyme primarily responsible for arsenic detoxification in humans and other animals, known as As3mt. They found that these mice were even more sensitive to arsenic after antibiotic treatment or when raised without microorganisms, compared to mice with unaltered microbiomes. When they introduced organisms from the human microbiome to germ-free mice lacking As3mt, they found that certain transplanted microorganisms had a protective effect, depending on microbiome stability and the presence of specific bacteria, including Faecalibacterium.
The results demonstrated that functional As3mt and specific microbiome members are needed for protection against acute arsenic toxicity in mice. According to the authors, the results show that the gut microbiome may become an important explanatory factor of arsenic-induced diseases in humans and a novel target for prevention and treatment strategies.
Citation: Coryell M, McAlpine M, Pinkham NV, McDermott TR, Walk ST. 2018. The gut microbiome is required for full protection against acute arsenic toxicity in mouse models. Nat Commun 9(1):5424.