Nanomedicines for modulating the gut-brain axis

The dysregulation of the gut-brain axis affects cerebral function, contributing to the occurrence of neuropsychiatric symptoms and the worsening of neurodegenerative disorders. The main and direct nerve connection between the gut and the brain is the gastrointestinal vagus nerve, which is activated by pathogenic bacteria. In the course of inflammatory bowel diseases, microbial dysbiosis and intestinal inflammation compromise the epithelial barrier, leading to increased levels of circulating pro-inflammatory cytokines, which cross the blood-brain barrier and trigger neuroinflammation. Restoring microbiota balance and effective delivery of neuroactive metabolites to the brain is therefore expected to attenuate both neuroinflammation and neuropsychiatric symptoms. This article highlights some recent manuscripts that take advantage of nanomedical tools to achieve modulation of the gut-brain axis responses, thus developing promising therapies for inflammatory and neurodegenerative disorders.