Microbial metabolite 3-indolepropionic acid alleviated PD pathologies by decreasing enteric glia cell gliosis via...

Area of Science:

• Neuroscience
• Gastroenterology
• Microbiology

Background:

• Enteric glial cell (EGC) activation is implicated in Parkinson's disease (PD) pathogenesis.
• Previous studies showed inhibiting EGC gliosis improves gut and dopaminergic neuronal function.
• The influence of gut microbiota on EGC function in PD requires further investigation.

Purpose of the Study:

• To investigate the role of gut microbiota in regulating EGC function in PD.
• To identify microbial metabolites that modulate EGC gliosis.
• To elucidate the protective mechanisms of identified metabolites against PD.

Main Methods:

• Fecal microbiota transplantation in a PD model.
• 16S rRNA gene sequencing and metabolomic analysis to profile gut microbiota and metabolites.
• In vitro studies using rotenone-stimulated EGCs.
• In vivo studies using rotenone-induced PD mouse models.
• Mechanistic studies involving receptor targeting and pathway analysis (PXR, JAK1-STAT6).

Main Results:

• Gut microbiota significantly regulates EGC function.
• 3-indolepropionic acid (IPA) was identified as a key microbial metabolite modulating EGC gliosis.
• IPA demonstrated protective effects in both in vitro and in vivo PD models, reducing inflammation and improving gut-brain barrier integrity and dopaminergic neuron function.
• IPA acts by targeting the pregnane X receptor (PXR) in EGCs, inhibiting the IL-13Rα1-mediated cytokine-cytokine receptor interaction, and inactivating the JAK1-STAT6 pathway.

Conclusions:

• EGC gliosis plays a critical role in the progression of gut-to-brain damage in PD.
• Microbial metabolite IPA shows therapeutic potential for alleviating PD pathology.
• Targeting the gut-brain axis via microbial metabolites like IPA offers a promising strategy for PD treatment.