Microbiome Composition and Function Contributes to Cognitive Impairment and Neuroinflammation in Parkinson's Disease

NCT05419453 · Status: RECRUITING · Type: OBSERVATIONAL · Enrollment: 100

Last updated 2024-02-08

No results posted yet for this study

Summary

Cognitive impairment is a common non-motor symptom among individuals living with Parkinson's disease (PD). Traditionally, cognitive impairment is thought to reflect disruptions in dopaminergic frontal-striatal systems. However, the current conceptualization does not thoroughly explain the heterogeneous profiles or trajectories of cognitive impairment in PD; suggesting that alternative mechanisms may contribute to cognitive impairments. Identification of alternative mechanisms of cognitive impairment may lead to better prognostic prediction and yield novel treatment targets. The gut is implicated as a site of early pathology in PD. Early signs of PD pathology (alpha synuclein and Lewy body aggregates) are detected in the gastrointestinal tract years before motor symptoms manifest. Recent studies provide evidence that individuals with PD have an altered gut-bacterial composition (termed dysbiosis) relative to controls. To date, dysbiosis is linked to more severe motor symptoms and certain non-motor symptoms (constipation, REM behavioral sleep disorder) in PD, but the relationship between dysbiosis and cognitive impairment remains unknown. Animal studies support the hypothesis that microbiota composition play a direct role in cognitive impairment. Germ free (GF) mice demonstrate deficits in cognition. Specifically, findings suggest that a disrupted gut- microbial environment in conjunction with elevated stress hormones may create an imbalance of pro- inflammatory vs. anti-inflammatory cytokines that induces potentially reversible cognitive impairments. In human studies among individuals with PD, neuroinflammatory markers are associated with cognitive impairment. However, the relationship between dysbiosis, neural inflammation and cognitive functioning remains unknown. This model has incredible clinical implications, as microbiota dysbiosis may represent a reversible risk factor for cognitive impairment. The proposed study will examine the hypothesis that dysbiosis contributes to increased neuroinflammation and cognitive impairment. Microbiota composition/function, neuroinflammatory markers and cognitive functioning will be examined in 100 participants with PD. Analyses of microbiota composition/function will examine abundance of amplicon sequence variants (ASVs; 16s), bacterial species/strains (metagenomics), microbial genes, and functional pathways. The investigators hypothesize that microbiota composition/function will be associated with inflammatory markers (e.g. interleukin-6, tumor necrosis factor-alpha, c-reactive protein) and cognitive impairment.

Conditions

  • Parkinson Disease

Sponsors & Collaborators

  • National Institutes of Health (NIH)

    collaborator NIH
  • National Institute of Neurological Disorders and Stroke (NINDS)

    collaborator NIH
  • California State University, San Bernardino

    lead OTHER

Eligibility

Min Age
55 Years
Max Age
85 Years
Sex
ALL
Healthy Volunteers
No

Timeline & Regulatory

Start
2021-04-30
Primary Completion
2026-04-30
Completion
2026-04-30

Countries

  • United States

Study Locations

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Read the full study record

This page highlights key information. For complete eligibility criteria, study locations, investigator contacts, and the full protocol, visit the original record on ClinicalTrials.gov.

View NCT05419453 on ClinicalTrials.gov