Evaluation of Modulation of Intestinal Microbiota in mice subjected to the Spontaneous Model of Aggressiveness.

Chronic stress can induce changes in different physiological systems, contributing to behavioral and systemic alterations, such as increased aggressiveness, dysregulation of the inflammatory response, and disruption of intestinal barrier integrity.Haptoglobin may be associated with inflammatory processes in the intestinal epithelium and, when analyzed together with pro-inflammatory cytokines, may contribute to the assessment of changes in the intestinal mucosa and barrier integrity. In this context, the present study investigated the effects of probiotic-mediated microbiota modulation in animals subjected to chronic social stress, evaluating haptoglobin and intestinal cytokine levels using the Spontaneous Aggressiveness Model.Swiss Webster mice were subjected to a grouping and regrouping protocol, allowing their classification into non-regrouped (NR), harmonic (Har), assaulted (AgD), and aggressor (AgR) animals according to their observed behavioral responses, followed by oral probiotic treatment for 6 weeks. Haptoglobin levels were evaluated in the jejunum and colon as a potential indicator of intestinal alterations using anenzyme-linked immunosorbent assay. No statistically significant differences were observed in haptoglobin levels among the control experimental groups in either the jejunum or colon, although variations in haptoglobin levels were observed among the animals. The cytokines IL-10, IL-17A, TNF-α, IFN-γ, IL-6, IL-4, and IL-2 were also evaluated. Significant differences were observed in TNF-α levels in the jejunum between the NR and Har groups and in IL-2 levels between the AgR and Har groups. In the colon, no statistically significant differences were observed among the groups. In conclusion, increasing the number of animals in the controlgroups is necessary to improve the reliability of theresults. In addition, experiments involving probiotic-treated animals are needed to evaluate the potential effects of probiotic treatment on intestinal barrier integrity.