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[INTESTINAL FAILURE AND YERSINIA PSEUDOTUBERCULOSIS TRANSLOCATION IN THE DEVELOPMENTOF EXPERIMENTAL GENERALIZED
The Objective:
To determine the value of intestinal failure and translocation of bacteria Y. pseudotuberculosis, and normal intestinal microbiota in the initiation and generalization of infection in experimental pseudotuberculosis in conventional white mice, as well as pathological manifestation of it as a response to the adhesion and colonization of the mucosus membrane by pathogenic bacteria Y. pseudotuberculosis.
Materials And Methods:
Experimental models of pseudotuberculosis in conventional white mice used the pathogenic Y. pseudotuberculosis 147 serotype I strain, containing a calcium-dependence plasmid with a molecular weight of 47 MDa. Cultivation of the pseudotuberculosis pathogen given its psychrophilic was performed on Hottinger agar at a temperature of (4-5) °C. The lactobacilli strain L plantarum 8P-A3 was isolated from a lyophilized commercial probiotic Lactobacterin (manufactured by "NPO Microgen", Russia) and used to obtain native culture supernatant fluid of lactobacilli, the composition of which was detected by gas-liquid chromatography with mass-selective detection. Gentamicin for parenteral administration was manufactured by JSC "Biochemist", Russia. Pathomorphological examination was performed on the 4-6th day of the experiment. Fragments of the small intestine, liver, kidneys, and lungs from dead animals were chosen for examination. Tissues were fixed in 10% neutral formalin, dehydrated in isopropanol and embedded in paraffin. Preparations were stained with Ehrlich hematoxylin and eosin, examined on the microscope "Mikmed-2" (JSC "LOMO", Russia) under magnification x 200-x1000. Statistical processing of the experimental results was carried out according to the method of Kerber in modification of I.P. Ashmarin and A.A. Vorobyov.
Results:
The role of intestinal failure and translocation of bacteria Y. pseudotuberculosis, and normal intestinal microbiota in the initiation and generalization of infection in animals has been found. It has been proved that the oral administration of supernatant fluid containing microbial metabolites to animals as intramuscular administration of gentamicin equally prevent the development of generalized pseudotuberculosis and intensity of pathomorphological changes in the intestine and other organs of animals.
Conclusion:
Metabolites of the probiotic lactobacilli strain L plantarum 8P-A3 jugulate the development of pseudotuberculosis at an early stage of the pathological process in experimental animals infected with pathogen Y pseudotuberculosis, not only causing the preservation of the colonization resistance of the intestinal mucosa that prevents the adhesion and colonization of the pathogen, but also through their antimicrobial impact on the dissiminated pseudotuberculosis patho-gen bacteria in animals.
Insights
Probiotic lactobacilli metabolites prevent generalized pseudotuberculosis infection in mice by maintaining intestinal barrier function and exhibiting antimicrobial effects against Yersinia pseudotuberculosis. This highlights a novel therapeutic strategy for bacterial infections.
Area of Science:
- Microbiology
- Pathology
- Immunology
Context:
- Experimental pseudotuberculosis in conventional white mice was studied to understand the role of intestinal failure and bacterial translocation.
- The study investigated the pathological manifestations of Yersinia pseudotuberculosis infection in response to bacterial adhesion and colonization.
Purpose:
- To determine the role of intestinal failure, bacterial translocation, and normal intestinal microbiota in the initiation and generalization of experimental pseudotuberculosis.
- To evaluate the pathological manifestations as a response to pathogen adhesion and colonization.
Summary:
- Oral administration of supernatant fluid from Lactobacillus plantarum 8P-A3, containing microbial metabolites, prevented generalized pseudotuberculosis and reduced pathomorphological changes in mice.
- Both the probiotic supernatant and gentamicin administration equally inhibited the development of severe infection and tissue damage.
Impact:
- Metabolites of L. plantarum 8P-A3 effectively control pseudotuberculosis development by preserving intestinal colonization resistance and exerting antimicrobial effects.
- This research suggests a potential therapeutic application of probiotic-derived metabolites in managing bacterial infections and preventing pathogen translocation.
