RESUMEN
Giardiasis, a parasitic infection of the gastrointestinal tract, is prevalent worldwide. The integrity of the intestinal epithelial barrier plays an important defensive role in giardiasis, and as Oral supplementation with prebiotics and probiotics is known to reinforce the intestinal barrier in many gastrointestinal diseases, this study assessed the effects of prebiotic and probiotic supplementation in giardiasis and compared the results with those obtained after nitazoxanide therapy. Swiss albino male lab-bred mice (n = 50) were divided into three major groups; Group I (control group), i.e., negative (noninfected nontreated) and positive controls (infected nontreated); Group II (preventive group), in which mice were provided prebiotic, probiotic, or a combination for 7 days before of infection, and Group III (therapy group), in which mice were administered prebiotic, probiotic, combined supplements and nitazoxanide from day 12 post-infection. The assessment was achieved through Giardia cyst count, histopathological examination and ultrastructure study. Also, Serological and immunohistochemical parameters were done to evaluate the modulation of IgA levels. Oral supplementation with prebiotic and probiotic, either before or after infection (in preventive or therapy groups respectively) resulted in a significant reduction in Giardia cyst shedding. Remarkable histological and ultrastructure improvement in the intestinal changes, along with a significant increase in the serological and immunohistochemical IgA levels, were seen in mice provided combined supplements and nitazoxanide (in therapy group). Thus, our results indicate that combined prebiotic and probiotic supplementation has promising anti-Giardia activity and that it can restore intestinal structures and modulate IgA response, apart from providing synergistic effects when added to nitazoxanide.