How Arsenic Impacts Gut Bacteria and Builds Up in Freshwater Organisms

Jenn Hoskins
17th May, 2024

How Arsenic Impacts Gut Bacteria and Builds Up in Freshwater Organisms

Image Source: Natural Science News, 2024

Key Findings

  • Researchers at South China Agricultural University studied the impact of arsenic on the gut microbiota of apple snails
  • Low arsenic levels increased gut bacteria, while high levels decreased them
  • Gut microbiota play a crucial role in arsenic bioaccumulation and biotransformation in apple snails
Arsenic, a toxic metalloid, poses significant risks to both human health and aquatic ecosystems. A recent study by researchers at South China Agricultural University[1] delves into the impact of arsenic stress on the gut microbiota of the apple snail (Pomacea canaliculata) and explores its role in arsenic bioaccumulation and biotransformation. This investigation provides new insights into how gut microbiota adapt to arsenic exposure and contribute to arsenic metabolism in freshwater invertebrates. The study conducted waterborne arsenic exposure experiments to analyze the gut microbiomes of apple snails. Results indicated that low concentrations of arsenic increased the abundance of gut bacteria, while high concentrations led to a decrease. The dominant bacterial phyla identified were Proteobacteria, Firmicutes, Bacteroidota, and Actinobacteriota. These findings align with previous research that highlights the significant role of gut microbiota in metal bioaccumulation and its potential impact on host health[2]. To further understand the involvement of gut microbiota in arsenic bioaccumulation and biotransformation, in vitro analyses were performed. These analyses confirmed that gut microbiota play a critical role in these processes. To validate these findings in vivo, the researchers administered antibiotic treatments to eliminate the gut microbiota in the snails, followed by exposure to waterborne arsenic. The results showed that antibiotic treatment reduced the total arsenic content and the proportion of arsenobetaine (a less toxic form of arsenic) in the snail's body. This indicates that the presence of gut microbiota enhances arsenic bioaccumulation and biotransformation in apple snails. The study also employed physiologically based pharmacokinetic (PBPK) modeling to gain a deeper understanding of the processes of bioaccumulation, metabolism, and distribution of arsenic in the snails. PBPK modeling is a mathematical modeling technique that predicts the absorption, distribution, metabolism, and excretion of chemicals in living organisms. This approach provided valuable insights into how arsenic is processed within the snail's body and the role of gut microbiota in these processes. Previous studies have highlighted the toxicity of different forms of arsenic to aquatic organisms. For example, research has shown that arsenite (As(III)) is more toxic to freshwater invertebrates like Daphnia carinata compared to arsenate (As(V))[3]. Additionally, studies on zebrafish (Danio rerio) have demonstrated that the intestines are the main uptake site for waterborne As(V), leading to high bioaccumulation of inorganic arsenic in muscle tissue[4]. These findings underscore the importance of understanding how different forms of arsenic are taken up and metabolized by aquatic organisms. The current study expands on these findings by focusing on the role of gut microbiota in arsenic metabolism in freshwater invertebrates. The adaptive response of gut microbiota to arsenic stress observed in apple snails suggests that these microorganisms play a crucial role in mitigating arsenic toxicity. This is particularly important given the potential human health risks associated with consuming arsenic-contaminated aquatic organisms. In conclusion, the research conducted by South China Agricultural University highlights the significant role of gut microbiota in the bioaccumulation and biotransformation of arsenic in apple snails. These findings provide valuable insights into the mechanisms by which gut microbiota respond to arsenic stress and contribute to arsenic metabolism in freshwater invertebrates. Understanding these processes is essential for developing strategies to mitigate the impact of arsenic pollution on aquatic ecosystems and human health.

EnvironmentBiochemAnimal Science

References

Main Study

1) Effects of arsenic on gut microbiota and its bioaccumulation and biotransformation in freshwater invertebrate.

Published 14th May, 2024

https://doi.org/10.1016/j.jhazmat.2024.134623

Related Studies

2) Low-level environmental metal pollution is associated with altered gut microbiota of a wild rodent, the bank vole (Myodes glareolus).

https://doi.org/10.1016/j.scitotenv.2021.148224

3) Toxicity of tri- and penta-valent arsenic, alone and in combination, to the cladoceran Daphnia carinata: the influence of microbial transformation in natural waters.

https://doi.org/10.1007/s10653-008-9239-9

4) Intestinal uptake and low transformation increase the bioaccumulation of inorganic arsenic in freshwater zebrafish.

https://doi.org/10.1016/j.jhazmat.2022.128904


Related Articles

An unhandled error has occurred. Reload 🗙