Evaluation of an Oral Subchronic Exposure of Deoxynivalenol on the Composition of Human Gut Microbiota in a Model of Human Microbiota-Associated Rats

Abstract

BackgroundDeoxynivalenol (DON), a mycotoxin produced by Fusarium species, is one of the most prevalent mycotoxins present in cereal crops worldwide. Due to its toxic properties, high stability and prevalence, the presence of DON in the food chain represents a health risk for both humans and animals. The gastrointestinal microbiota represents potentially the first target for these food contaminants. Thus, the effects of mycotoxins on the human gut microbiota is clearly an issue that needs to be addressed in further detail. Using a human microbiota-associated rat model, the aim of the present study was to evaluate the impact of a chronic exposure of DON on the composition of human gut microbiota.Methodology/Principal FindingsFour groups of 5 germ free male rats each, housed in 4 sterile isolators, were inoculated with a different fresh human fecal flora. Rats were then fed daily by gavage with a solution of DON at 100 µg/kg bw for 4 weeks. Fecal samples were collected at day 0 before the beginning of the treatment; days 7, 16, 21, and 27 during the treatment; and 10 days after the end of the treatment at day 37. DON effect was assessed by real-time PCR quantification of dominant and subdominant bacterial groups in feces. Despite a different intestinal microbiota in each isolator, similar trends were generally observed. During oral DON exposure, a significant increase of 0.5 log10 was observed for the Bacteroides/Prevotella group during the first 3 weeks of administration. Concentration levels for Escherichia coli decreased at day 27. This significant decrease (0.9 log10 CFU/g) remained stable until the end of the experiment.Conclusions/SignificanceWe have demonstrated an impact of oral DON exposure on the human gut microbiota composition. These findings can serve as a template for risk assessment studies of food contaminants on the human gut microbiota.

Impact of Ceftiofur Injection on Gut Microbiota and Escherichia coli Resistance in Pigs

“…For all samples collected from pigs in rooms 1A to 1D, previously validated quantitative PCR (qPCR) analyses, all targeting 16S rRNA gene fragments, were carried out to evaluate the change in abundance of the total bacterial population and of the numbers of Bacteroides/Prevotella, Bifidobacterium, E. coli, Enterococcus, and Lactobacillus/ Leuconostoc/Pediococcus (23). qPCR for quantification of bla CTX-M-1 gene copies was performed (24) for samples collected from the six animal rooms during the first week and from rooms 1A to 1D thereafter; the copy numbers were determined by comparison with decimal dilutions of plasmid DNA prepared from the bla CTX-M-1 gene previously cloned in the plasmid pCR4-TOPO in the One Shot TOP10 E. coli strain (Life Technologies, St. Aubin, France), according to the manufacturer's instructions.…”

Lactic Acid Bacteria as Antifungal and Anti‐Mycotoxigenic Agents: A Comprehensive Review

“…DON exposure is also related to acute gastrointestinal disorder and inhibition of DNA and protein synthesis, which leads to immune‐suppression (Sun, Su, & Shan, ). The ingestion of DON also poses a great threat to human health through serious modulations in the composition of the human gut microflora, which affects normal host functions (Saint‐Cyr, Perrin‐Guyomard, Houee, Rolland, & Laurentie, ). DON derivatives (DON‐3‐glucoside, 15‐acetyldeoxynivalenol, and 3‐acetyldeoxynivalenol) are equally a safety concern for consumers (Vidal, Mengelers, Yang, De Saeger, & De Boevre, ).…”

Impacts of the feed contaminant deoxynivalenol on the intestine of monogastric animals: poultry and swine

“…Although there are indications that DON exposure might disrupt the balance and diversity of commensal microbiota and cause dysbiosis, as reported in one pig study (Waché et al, 2009), the information regarding the potential impacts of DON on gut microbiota in pigs and chickens is still scarce. One recent study, conducted in a rat model, evaluated the impact of a chronic exposure of DON on the composition of gut microbiota (Saint-Cyr et al, 2013). These authors reported that during oral DON exposure (100 μg kg -1 body weight for 4 weeks), a significant increase was observed in Bacteroides spp.…”

“…Therefore, this area of research needs to be addressed in domestic animals including poultry and pigs using molecular microbiological techniques that allow a deep evaluation of the communities, function, and their metabolic activity. Major attention should also be given to the elucidation of the effects of dose and duration of DON exposure because ingestion of DON for long periods and at different doses may have adverse effects on the intestinal microbiota and their metabolic activity (Saint-Cyr et al, 2013). Also, because diet has an important impact on the diversity of gut microbiota of pigs (Metzler-Zebeli et al, 2009Mann et al, 2014) and poultry (Stanley et al, 2013), further research is needed to evaluate interactions among dietary ingredients or additives (probiotics, prebiotics and phytobiotics) and DON exposure on the gut microbiota of pigs and poultry.…”