Related Experiment Video

Updated: Jun 13, 2025

Quantitative 3D In Silico Modeling q3DISM of Cerebral Amyloid-beta Phagocytosis in Rodent Models of Alzheimer's Disease
09:33

Quantitative 3D In Silico Modeling q3DISM of Cerebral Amyloid-beta Phagocytosis in Rodent Models of Alzheimer's Disease

Published on: December 26, 2016

7.9K

Gut bacterial metabolite imidazole propionate potentiates Alzheimer's disease pathology

Vaibhav Vemuganti1,2, Jea Woo Kang3, Qijun Zhang1

  • 1Department of Bacteriology, University of Wisconsin-Madison; Madison, WI, USA.

Biorxiv : the Preprint Server for Biology
|June 12, 2025
PubMed

Insights

A gut bacterial metabolite, imidazole propionate (ImP), is linked to cognitive decline and Alzheimer's disease (AD) biomarkers. This metabolite may drive AD progression through neurodegenerative and cerebrovascular pathways, offering a potential early intervention target.

Area of Science:

  • Microbiology
  • Neuroscience
  • Metabolomics

Background:

  • The gut microbiome influences host metabolism, immunity, and neurological function.
  • Alzheimer's disease (AD) pathogenesis involves complex interactions, including potential gut microbiome contributions.
  • The bacterial metabolite imidazole propionate (ImP) is associated with AD comorbidities like type 2 diabetes.

Purpose of the Study:

  • To investigate the association between plasma ImP levels and cognitive function in individuals at risk for AD.
  • To explore the role of gut bacteria in ImP synthesis and its correlation with AD biomarkers.
  • To determine the impact of ImP on neurodegeneration and blood-brain barrier (BBB) integrity.

Main Methods:

  • Analysis of plasma ImP levels and cognitive scores in a cohort of over 1,100 cognitively unimpaired individuals.
  • Metagenomic profiling to identify ImP-producing gut bacteria and correlate their abundance with cognitive and AD biomarkers.
  • Experimental administration of ImP to mice to assess neurodegenerative pathways, AD-like neuropathology, and BBB permeability.
  • In vitro studies using human brain endothelial cells to evaluate ImP's effect on cellular integrity.

Main Results:

  • Elevated plasma ImP levels correlated with lower cognitive scores and increased AD biomarkers.
  • Abundance of gut bacteria encoding the ImP-synthesizing enzyme (urocanate reductase, UrdA) correlated with cognitive measures and AD biomarkers.
  • Chronic ImP administration in mice activated neurodegenerative pathways, exacerbated AD-like neuropathology, and increased BBB permeability.
  • In vitro studies demonstrated that ImP compromises the integrity of human brain endothelial cells.

Conclusions:

  • Elevated ImP is associated with cognitive impairment and AD pathology.
  • ImP may contribute to AD progression by inducing neurodegeneration and compromising cerebrovascular integrity.
  • ImP represents a potential therapeutic target for early intervention in Alzheimer's disease.

More Related Videos

Detection of Neuritic Plaques in Alzheimer's Disease Mouse Model06:02

Detection of Neuritic Plaques in Alzheimer's Disease Mouse Model

Published on: July 26, 2011

36.6K
Biochemical Purification and Proteomic Characterization of Amyloid Fibril Cores from the Brain09:00

Biochemical Purification and Proteomic Characterization of Amyloid Fibril Cores from the Brain

Published on: April 28, 2022

3.1K

Related Concept Videos

Alzheimer's Disease: Overview01:26

Alzheimer's Disease: Overview

Alzheimer's Disease (AD) is a continually advancing neurodegenerative disorder, distinguished by escalating memory loss, cognitive dysfunction, and dementia. The disease unfolds in three stages: preclinical, mild cognitive impairment (MCI), and dementia. Its onset is insidious, and the progression gradual, with the cause not well explained by other disorders.
The clinical diagnosis of AD hinges on the presence of memory and other cognitive impairments. Biomarkers, such as changes in Aβ...
451
Alzheimer's Disease: Treatment01:22

Alzheimer's Disease: Treatment

Alzheimer's Disease (AD), a neurodegenerative disorder, is pathologically identified by amyloid plaques and neurofibrillary tangles composed of tau protein. AD pharmacotherapy aims to manage cognitive symptoms, delay disease progression, and treat behavioral symptoms. The treatment is primarily symptomatic and palliative, with no definitive disease-modifying therapy available. Cholinesterase inhibitors, including donepezil (Aricept), rivastigmine (Exelon), and galantamine (Razadyne), are...
170
Amyloid Fibrils03:03

Amyloid Fibrils

Amyloid fibrils are aggregates of misfolded proteins.  Under most circumstances, misfolded proteins are either refolded by chaperone proteins or degraded by the proteasome. However, in the case of a mutation or a disease, these proteins can accumulate to form large clusters and often further assemble to form elongated fibers, called fibrils. 
Amyloid deposits were observed as early as 1639 in the liver and the spleen.   In 1854, Rudolph Virchow performed iodine staining,...
9.3K
Role of Neurotransmitters in Memory01:23

Role of Neurotransmitters in Memory

Neurotransmitters are integral to the brain's communication system, enabling neurons to transmit signals across synapses. This chemical exchange underpins various cognitive functions, including memory processes. The role of neurotransmitters in memory is multifaceted, influencing the encoding, consolidation, and retrieval of memories through their action on different neural circuits.
 Glutamate and Synaptic Plasticity
Glutamate, the brain's main excitatory neurotransmitter, is...
478
Irritable Bowel Syndrome I: Introduction01:17

Irritable Bowel Syndrome I: Introduction

Irritable Bowel Syndrome (IBS) is characterized by functional disturbances in the gastrointestinal system, presenting a cluster of symptoms without evident structural or biochemical abnormalities. It primarily affects the large intestine and may cause abdominal pain, bloating, excessive gas, diarrhea, constipation, or both.
IBS is a chronic condition that can persist over a long period or recur frequently.
The pathogenesis of IBS involves a complex interplay of the following factors:
Altered...
255