Fig. 4

Gut-brain axis: microbiota-derived EVs as modulators of neural integrity. This schematic illustrates the dichotomous influences of EVs derived from gut microbiota on neural health. Probiotic EVs, originating from beneficial commensals, confer neuroprotective effects, which may ameliorate NDD pathology. Conversely, disruption of gut homeostasis allows pathogenic bacteria to release EVs that can translocate across the intestinal and the BBB. These vesicles transport inflammatory components, such as LPS, peptidoglycans, and bacterial toxins, into the CNS, potentially inducing immune responses that precipitate neuroinflammation and the aggregation of neurotoxic proteins