Frontiers in Immunology (Jun 2021)

Chronic Stress-Induced Depression and Anxiety Priming Modulated by Gut-Brain-Axis Immunity

  • Susan Westfall,
  • Francesca Caracci,
  • Molly Estill,
  • Tal Frolinger,
  • Li Shen,
  • Giulio M. Pasinetti,
  • Giulio M. Pasinetti

DOI
https://doi.org/10.3389/fimmu.2021.670500
Journal volume & issue
Vol. 12

Abstract

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Chronic stress manifests as depressive- and anxiety-like behavior while recurrent stress elicits disproportionate behavioral impairments linked to stress-induced immunological priming. The gut-brain-microbiota-axis is a promising therapeutic target for stress-induced behavioral impairments as it simultaneously modulates peripheral and brain immunological landscapes. In this study, a combination of probiotics and prebiotics, known as a synbiotic, promoted behavioral resilience to chronic and recurrent stress by normalizing gut microbiota populations and promoting regulatory T cell (Treg) expansion through modulation of ileal innate lymphoid cell (ILC)3 activity, an impact reflecting behavioral responses better than limbic brain region neuroinflammation. Supporting this conclusion, a multivariate machine learning model correlatively predicted a cross-tissue immunological signature of stress-induced behavioral impairment where the ileal Treg/T helper17 cell ratio associated to hippocampal chemotactic chemokine and prefrontal cortex IL-1β production in the context of stress-induced behavioral deficits. In conclusion, stress-induced behavioral impairments depend on the gut-brain-microbiota-axis and through ileal immune regulation, synbiotics attenuate the associated depressive- and anxiety-like behavior.

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