Disrupted Paraventricular Hypothalamic Nucleus Functional Connectivity in Parkinson's Disease With Constipation

Area of Science:

• Neuroscience
• Gastroenterology
• Neurology

Background:

• Constipation is a common non-motor symptom in Parkinson's disease (PD), often appearing early.
• The exact causes of constipation in PD are not fully understood.
• Previous research suggests a link between gastrointestinal dysfunction and altered functional connectivity in the paraventricular hypothalamic nucleus (PVN).

Purpose of the Study:

• To investigate the role of the PVN in the development of constipation in early-stage PD patients.
• To compare brain network organization between PD patients with and without constipation.
• To explore the relationship between PVN functional connectivity and symptom severity in PD.

Main Methods:

• Enrolled 66 PD patients (with and without constipation) and 30 healthy controls.
• Acquired T1-weighted and resting-state functional MRI (fMRI) scans for all participants.
• Utilized voxel-based morphometry and functional connectivity analyses.

Main Results:

• PD patients with constipation showed decreased functional connectivity in the PVN-pontine tegmentum pathway compared to those without constipation (p=0.006).
• No differences in basal ganglia circuitry were found between the two PD groups.
• PVN-pontine tegmentum functional connectivity negatively correlated with UPDRS and NMSS scores.
• Significant differences in functional connections involving the inferior frontal gyrus and cerebellum were observed between PD groups.
• No statistical differences in gray matter volume were detected.

Conclusions:

• Abnormal PVN functional connectivity is implicated in the mechanism of constipation in Parkinson's disease.
• The inferior frontal gyrus and cerebellum may also play a role in the occurrence of constipation in PD patients.
• This study offers insights into the neurobiological underpinnings of constipation in PD.