Author: Chen Lianguo / Institute of Hydrobiology, Chinese Academy of Sciences
In the process of zebrafish growth and development, the addition of probiotics can reshape the intestinal flora, regulate lipid metabolism-related genes, and reduce cholesterol and triglyceride content. Perfluorobutanesulfonate (PFBS) is an emerging persistent organic pollutant with serious water pollution in china (Figure 1), which can interfere with the composition of fish intestinal flora and lead to dyslipidemia. Recently, a team of Chen Lianguo researchers from the Institute of Hydrobiology, Chinese Academy of Sciences revealed for the first time the ability of the probiotic Lactobacillus rhamnosus to regulate the disorder of lipid metabolism caused by PFBS exposure. Related research results were published in the journal Environmental Science & Technology.
Figure 1. PFBS chemical structure
The toxicology and health risks of persistent organic pollutants have become a major environmental safety issue in china. With the large-scale production and use, PFBS has been widely present in the water environment of china, especially Hubei Province. The concentration of PFBS water in Tangxun Lake in Wuhan is as high as 8 μg/L. Exposure to the true dose of PFBS environment can permanently and intergenerationally interfere with the intestinal microbial community of fish and damage intestinal health and lipid metabolism. Therefore, it is of practical environmental significance to further clarify and regulate the toxic health hazards of PFBS.
In this study, the authors used zebrafish adult fish as experimental subjects, and were fed with no probiotics and supplemented with probiotic L. rhamnosus, and were exposed to environmentally relevant doses of PFBS (0 μg/L, 10 μg/ L and 100 μg/L) for 28 days, aiming to explore the regulatory effect of probiotic additives on PFBS intestinal microbial and lipid metabolism interference. According to PFBS exposure concentration and zebrafish gender differences, feeding probiotics changed the intestinal toxicity of PFBS, including intestinal epithelial integrity, inflammation, endotoxin and oxidative stress. Amplicon sequencing found that the relative abundance of Lactobacillus genus did not change, but it was significantly positively correlated with other intestinal intrinsic beneficial bacteria (P <0.001; r >0.5), indicating that probiotics indirectly regulate the host metabolic activity.
In order to study the regulatory effects of probiotics on PFBS lipid metabolism toxicity, the authors examined the physiological processes related to lipid metabolism in the intestine, blood and liver, involving fat digestion and transport absorption, bile acid metabolism, fatty acid beta oxidation and synthesis, triglycerides Synthesis and hydrolysis, and nuclear receptor pathways. In the co-treatment group of PFBS and probiotics, the fatty acid synthesis and β oxidation process of female zebrafish were significantly enhanced. Probiotics also inhibited the accumulation of blood cholesterol caused by PFBS exposure alone, proving that probiotic L. rhamnosus is healthy for zebrafish hosts. Beneficial effect (Figure 2).
Figure 2. Diagram of lipid metabolism in female zebrafish
In males, probiotic additives antagonize the interference of PFBS on bile acid metabolism, which may be mediated by the farnesoid X receptor (FXR) signaling pathway (Figure 3). However, the co-exposure of PFBS and probiotics significantly increased the male body index and the content of triglycerides in the liver, which may lead to fatty liver (Figure 3).
Figure 3. Diagram of lipid metabolism in male zebrafish
In summary, this article reveals for the first time the regulatory effect of probiotic bacteria on the toxic effects of water environment pollutants. In terms of intestinal microbial community and lipid metabolism, gender differences determine the mode of interaction between probiotics and pollutants. Considering the wide application of probiotics in aquaculture, fishery resources and human health, the relevant results provide a basic data reference for evaluating the application value of probiotics. Especially in areas with severe environmental pollution, the application of probiotics requires comprehensive consideration of the potential impact of pollutants.
Disclaimer: This article is translated by cpolymer. The translation is for reference only. All contents are subject to the original text.