Food for thought: probiotic modulation of microglial activity in Parkinson's disease

Area of Science:

• Neuroscience
• Microbiology
• Immunology

Background:

• The gut-brain axis and gut microbiome (GM) are increasingly implicated in Parkinson's disease (PD) pathogenesis.
• Gut dysbiosis contributes to neuroinflammation and dopaminergic neuron loss via altered microglial activity.
• Microbial imbalances can compromise intestinal barrier function, promoting systemic inflammation and potentially facilitating alpha-synuclein pathology.

Purpose of the Study:

• To review the role of the gut microbiome in PD.
• To evaluate the therapeutic potential of probiotics in modulating the gut-brain axis for PD.
• To identify current limitations and future directions for microbiota-based interventions in PD.

Main Methods:

• Synthesis of preclinical (animal) and clinical (human) studies on probiotics and PD.
• Analysis of mechanisms linking GM, microglial activation, and neuroinflammation.
• Review of human trials focusing on gastrointestinal, non-motor, and neuroimmune outcomes in PD.

Main Results:

• Preclinical data demonstrate probiotics can restore GM balance, enhance gut barrier integrity, and reduce microglial reactivity and alpha-synuclein aggregation in PD models.
• Human trials suggest probiotics may benefit gastrointestinal and non-motor symptoms, with potential impacts on systemic inflammation and neuroimmune signaling.
• Direct evidence for probiotic-induced central microglial modulation in human PD remains limited.

Conclusions:

• Probiotics represent a promising avenue for non-invasive, disease-modifying strategies in Parkinson's disease.
• Targeting the gut microbiome offers therapeutic potential for managing neuroinflammation and neurodegeneration in PD.
• Further clinical investigation is required to validate the efficacy of probiotics in modulating central neuroinflammation and disease progression in PD.