The Brain-Gut Axis in Parkinson's Disease Pathology

Area of Science:

• Neuroscience
• Gastroenterology
• Pathology

Background:

• Parkinson's disease (PD) is a common neurodegenerative disorder with motor and non-motor symptoms.
• The brain-gut axis plays a critical role in PD, with pathology potentially originating in the gastrointestinal (GI) tract.
• Environmental factors like pesticides may initiate PD pathology, leading to alpha-synuclein misfolding and Lewy Bodies.

Purpose of the Study:

• To review the progression of Parkinson's disease pathology across the brain-gut axis.
• To elucidate the roles of oxidative stress and glial activation in PD pathogenesis.
• To highlight the therapeutic potential of targeting early brain-gut axis mechanisms in PD.

Main Methods:

• Literature review of studies on Parkinson's disease and the brain-gut axis.
• Analysis of evidence linking GI dysfunction to PD.
• Examination of the roles of oxidative stress and glial activation in neurodegeneration.

Main Results:

• Evidence suggests PD pathology can originate in the GI tract and spread via the vagus nerve ("body-first") or from the brain ("brain-first").
• Oxidative stress and glial activation in the enteric nervous system and vagal nerve nuclei may precede neurodegeneration.
• These early changes can drive the retrograde spread of pathology to the brain.

Conclusions:

• The brain-gut axis is central to Parkinson's disease progression.
• Oxidative stress and glial activation are critical early contributors to neuronal loss in PD.
• Targeting these mechanisms offers potential for early therapeutic intervention in Parkinson's disease.