Efeitos da administração da inulina sobre a microbiota e comportamentos do tipo ansiosos em camundongos C57BL6J fêmeas e machos, filhos de progenitoras tratadas com antígenos solúveis de Toxoplasma gondii (STAg)

Abstract

The gut-brain axis is a bidirectional communication that occurs between the central nervous system and the intestine, with involvement of the intestinal microbiota. It is known that the imbalance of this microbiota is related to psychiatric disorders, while the consumption of insoluble fibers, prebiotics, increases beneficial microorganisms and promotes health. Since animal models of maternal immunoactivation (MIA) have been used to induce behavioral changes in adult offspring, the present study aimed to investigate whether the induction of MIA using suspension of soluble antigens of T. gondii (STAg) in pregnant female mice of the C57BL6J lineage causes changes in the offspring's anxious behavior, as well as to analyze whether the prebiotic inulin, administered during lactation, promotes neuroprotection in adult offspring through modulation of the microbiota. We administered STAg or PBS to the dams by intraperitoneal injection in a single dose, at 16 days of gestation, while inulin or water were administered orally to the offspring daily during lactation. To investigate the presence of anxietylike behaviors, the Elevated Plus Maze Test was performed. Statistical differences were considered significant if p<0.05. Data were presented as mean ± SEM. Our results showed a “tendency” of the immunogenic challenge with STAg to generate anxiety-like behaviors, when we analyzed different parameters of the LCE test. Although the differences were not significant in the female offspring whose dams were challenged with STAg, groups G3-STAg+water (6.5±10.64) and G4-STAg+inulin (234.5±7.90), we observed shorter exploration time of the open arms and increased time in the closed arms, behaviors associated with a higher level of anxiety. In male offspring, the gestational challenge with STAg significantly reduced the number of stretch-attend postures in an unprotected area in the G4-STAg + inulin group (3±0.91) compared to the G2-PBS+water group (8±0.63), indicating an anxiogenic effect. Inulin treatment in female offspring significantly reduced (p<0.05) the number of entries into the closed arms of the apparatus (G2-10±12.48) when compared to animals in group G1 (14±12.03), demonstrating an anxiolytic effect. For the other parameters evaluated, inulin did not significantly modify the behavior of the animals studied, although it showed a tendency for an anxiolytic effect. Adjustments in the inulin dosage may be necessary in future experiments to confirm the protective effect of using this prebiotic in the early stages of life. Keywords: Psychiatric disorders, gut-brain axis, maternal immunoactivation, microbiota, inulin, elevated plus maze.