The role of microbial amyloid in neurodegeneration

Area of Science:

• Microbiology
• Neuroscience
• Immunology

Background:

• The intestinal microbiota significantly impacts host metabolism, immunity, and development.
• Emerging evidence links the gut microbiota to brain function in both health and disease.
• Intestinal bacteria are implicated in the pathogenesis of neurodegenerative disorders such as Parkinson and Alzheimer diseases.

Purpose of the Study:

• To review current knowledge on bacterial amyloids and their role in neuroinflammation and cerebral amyloid aggregation.
• To explore the mechanisms by which microbial proteins or metabolites influence neurodegeneration.
• To introduce the term "mapranosis" for microbiota-associated proteopathy and neuroinflammation.

Main Methods:

• Literature review of studies on bacterial amyloids, protein misfolding, and neuroinflammation.
• Analysis of proposed mechanisms linking microbial products to neurodegenerative processes.
• Synthesis of existing data to define and conceptualize microbiota-associated proteopathy.

Main Results:

• Bacterial amyloids and metabolites may promote endogenous protein misfolding and enhance inflammatory responses.
• These microbial factors can influence the aggregation of amyloid proteins in the brain.
• The proposed term "mapranosis" encapsulates microbiota-associated proteopathy and neuroinflammation.

Conclusions:

• The gut microbiota plays a crucial role in brain health and disease, particularly neurodegeneration.
• Microbial amyloid proteins represent a novel factor in the pathogenesis of diseases like Parkinson and Alzheimer.
• Targeting the microbiota and its products offers a promising therapeutic avenue for neurodegenerative disorders.