Gut microbiota represents a critical factor which significantly influences the pathophysiology of the parasitic infections. Parasite’s survival and the outcome of many parasitic infections depend on the gut commensal microbiota and their production of nutritious macromolecules. Probiotic strains with their health benefits are able to inhibit, displace and compete with pathogens in the host gut, and enhance mucosal barrier activity. These beneficiary properties are strain-specific.
The aim of this work was to study an influence of probiotic and bacteriocin-producing bacterial strains on the intensity of parasitic Trichinella spiralis infection in experimental mice and the fertility of T. spiralis females.
Bacterial strains of different origin (Enterococcus faecium EF55, E. faecium 2019-CCM7420, E. faecium AL41-CCM8558, E. durans 26E/7, Lactobacillus fermentum AD1-CCM7421, L. plantarum 17L/1) were administered daily in dose of 109 CFU/ml in 100 µl and mice were infected with 400 larvae of T. spiralis on 7th day of treatment. T. spiralis adults were collected from the small intestine by lavage and muscle larvae were obtained by artificial digestion. Female adults of T. spiralis were isolated from mice treated with probiotic strains on 5th day post infection and used in fertility test ex vivo. A direct impact of bacterial strains on fertility was examined in vitro by co-cultivation of females isolated from untreated infected mice on 5th day post infection with probiotic strains.
Bacteriocin-producing strains E. faecium AL41-CCM8558, E. faecium 2019-CCM7420 and E. durans 26E/7 significantly reduced the number of adults in the intestine of mice. Application of probiotic strain L. plantarum 17L/1 and bacteriocin-producing strains L. fermentum AD1-CCM7421, E. faecium AL41-CCM8558 and E. durans 26E/7 caused a significant decrease in the number of muscle larvae. The reproductive capacity index (RCI) of T. spiralis was reduced in mice with administration of E. faecium AL41-CCM8558, E. durans 26E/7, L. fermentum AD1-CCM7421 a L. plantarum 17L/1. The greatest inhibitory effect on fertility of T. spiralis females was observed in mice with application E. faecium AL41-CCM8558, E. durans 26E/7, L. fermentum AD1-CCM7421 and L. plantarum 17L/1, which correlated with the total anti-parasitic effect of these strains. The highest in vitro efficiency was detected after incubation of T. spiralis females with L. fermentum AD1-CCM7421. Strain E. durans 26E/7 showed the highest difference between ex vivo and in vitro results. It could be caused by other factors, e.g. physiology of the intestine or immunomodulatory action of the bacterial strain. The results confirmed anti-parasitic effect of examined probiotic strains, which is strain-specific and probiotic bacteria can play an important role in reducing the pathogenicity of parasites.
This work was supported by Slovak Grant Agency VEGA No. 2/0081/15.