Impact of spray-dried Lactiplantibacillus plantarum CIDCA 83114 on a murine model of giardiasis

This study investigates the efficacy of spray-dried Lactiplantibacillus plantarum CIDCA 83114 in a murine model of giardiasis. Mice (C57BL/6) were divided into four groups: control, Giardia-only, probiotic-only, and a combined (probiotic+Giardia, PG) group. Probiotic treatment started one week pre-infection with Giardia intestinalis H7 and continued throughout the study. Infection was monitored through trophozoite counts, intestinal histology, cytokine expression and microbiome analysis. Histology revealed that the administration of strain CIDCA 83114 prior to infection, increases villus/crypt ratios compared with control infected animals. In addition, trophozoite counts in the small intestine were lower in probiotic-treated mice than in infected control animals. Probiotic-treated infected mice showed significantly higher IL-10 expression than untreated controls. Expression of the IL-12 gene was diminished in animals administered with strain CIDCA 83114 (both infected and non-infected with Giardia). In addition, Giardia infection led to a decrease in IFN-γ expression, even when the probiotic-treated animals. Expression of TNF-α increased in the groups treated only with strain CIDCA 83114 and in infected animals. Notably, the PG group exhibited lower values of TNF-α expression, potentially due to the elevated IL-10 levels detected in this group. Dysbiosis associated with Giardia infection led to an increase in Epsilonproteobacteria and Clostridium. These changes were abrogated in the group that received the probiotic strain, which, as expected, showed an increase in Lactobacillaceae. This study demonstrates that spray-dried probiotic L. plantarum CIDCA 83114 has a positive impact on key aspects of Giardia infection, supporting its potential as a preventive or therapeutic strategy for giardiasis.