Use of molecular typing to investigate bacterial translocation from the intestinal tract of chlorpyrifos-exposed rats

Abstract

BackgroundHuman are confronted on a daily basis with contaminant pesticide residues in food, water and other components of the environment. Although the digestive system is the first organ to come into contact with food contaminants, very few data are available on the impact of low-dose pesticide exposure during the in utero and postnatal periods on intestinal bacterial translocation (BT). Previous studies have revealed that chlorpyrifos (CPF) exposure is associated with intestinal dysbiosis and the contamination of sterile organs. Here, molecular typing was used to investigate intestinal bacterial translocation in rats exposed to chlorpyrifos in utero and during lactation. The translocated bacteria were profiled, and CPF tolerance and antibiotic resistance traits were determined.MethodsA total of 72 intestinal segments and extra-intestinal organs were obtained from 14 CPF-exposed rats. The samples were cultured to isolate bacterial strains that had tolerated treatment with 1 or 5 mg CPF/kg bodyweight/day in vivo. Strains were identified using matrix-assisted laser desorption/ionization (MALDI) Biotyper. The disk diffusion method was used to determine the antibiotic susceptibility. The isolates were genotyped with PCR assays for the enterobacterial repetitive intergenic consensus sequence and random amplification polymorphic DNA.ResultsBacterial translocation was confirmed for 7 of the 31 strains (22.6 %) isolated from extra-intestinal sites. Overall, the most prevalent bacteria were Staphylococcus aureus (55.5 % of the 72 intestinal and extra-intestinal isolates), Enterococcus faecalis (27.7 %) and Bacillus cereus (9.8 %). 5 % of the S. aureus isolates displayed methicillin resistance. Seventy two strains were identified phenotypically, and seven translocated strains (mainly S. aureus) were identified by genotyping. Genotypically confirmed translocation was mainly observed found in pesticide-exposed groups (6 out of 7).ConclusionBT from the intestinal tract colonized normally sterile extra-intestinal organs in CPF-exposed rats. Our findings validate the use of molecular typing for the assessment of intestinal BT in CPF-exposed rats during critical periods of development.

Effects of intestinal alkaline phosphatase on intestinal barrier function in a cecal ligation and puncture (CLP)‐induced mouse model for sepsis

“…Afterward, culture enrichment was added and cultures were followed up to another 48 hours before final identification of cultured strains with MALDI‐TOF. Bacterial translocation was considered to have occurred in case enteropathogens were demonstrated with MALDI‐TOF …”

“…Bacterial translocation was considered to have occurred in case enteropathogens were demonstrated with MALDI-TOF. 41…”

Impact of Oral Probiotics in Amelioration of Immunological and Inflammatory Responses on Experimentally Induced Acute Diverticulitis

“…The specimens were subjected to a series of tenfold dilutions in sterile nutrient broth, and triplicate samples of 100 μl from each dilution were plated on nutrient agar. Plates were incubated aerobically at 37 °C for 18 h. The aerobic bacterial count was expressed as colony-forming units (CFU) per gram of tissue [20,21]. To meet the criteria for statistical accuracy of bacterial numbers in given specimen samples, they were plated in triplicate, and CFU was counted only from plates yielding between 20 and 200 visible colonies [22].…”

900 MHz Electromagnetic Fields Induce Microbiota Dysbiosis and Adaptive Immune System Disorders in Juvenile Rats

“…The spleen was removed for the culture of translocated organisms. Bacteria were counted and identi ed according to their characteristic colonies and microscopic features and by using matrix-assisted laser desorption ionization time-of-ight mass spectroscopy (as described by Joly et al 54 ) under aseptic conditions. Thawed tissue samples were placed in sterile, preweighed glass containers.…”