[Personal View] The gut microbiome, systemic inflammation, and autoimmunity in Parkinson's disease

Inflammation is a core feature of Parkinson's disease, extending beyond the CNS to include systemic immune activation. The gut microbiome is increasingly recognised as a key regulator of immune function in the gastrointestinal tract, peripheral circulation, and brain. In individuals with Parkinson's disease, gut microbial composition is altered, with reductions in anti-inflammatory taxa and increases in pro-inflammatory bacterial species. Preclinical studies have shown that microbiome alterations can promote α-synuclein aggregation and neuroinflammation, whereas human data suggest early involvement of the gut and immune system.