TY - JOUR
T1 - The Role of Chronic Infection in Alzheimer’s Disease
T2 - Instigators, Co-conspirators, or Bystanders?
AU - Butler, Lauren
AU - Walker, Keenan A.
N1 - Funding Information:
This research was supported in part by the Intramural Research Program of the NIH, National Institute on Aging. This study was also supported by contracts K23 AG064122 (Dr. Walker). Compliance with the National Institutes of Health (NIH) Public Access Policy requires proper submission of this work to PubMed Central (PMC).
Publisher Copyright:
© 2021, This is a U.S. government work and not under copyright protection in the U.S.; foreign copyright protection may apply.
PY - 2021/12
Y1 - 2021/12
N2 - Purpose of Review: Herein, we provide a critical review of the clinical and translational research examining the relationship between viral and bacterial pathogens and Alzheimer’s disease. In addition, we provide an overview of the biological pathways through which chronic infection may contribute to Alzheimer’s disease. Recent Findings: Dementia due to Alzheimer’s disease is a leading cause of disability among older adults in developed countries, yet knowledge of the causative factors that promote Alzheimer’s disease pathogenesis remains incomplete. Over the past several decades, numerous studies have demonstrated an association of chronic viral and bacterial infection with Alzheimer’s disease. Implicated infectious agents include numerous herpesviruses (HSV-1, HHV-6, HHV-7) and various gastric, enteric, and oral bacterial species, as well as Chlamydia pneumonia and multiple spirochetes. Summary: Evidence supports the association between multiple pathogens and Alzheimer’s disease risk. Whether these pathogens play a causal role in Alzheimer’s pathophysiology remains an open question. We propose that the host immune response to active or latent infection in the periphery or in the brain triggers or accelerates the Alzheimer’s disease processes, including the accumulation of amyloid-ß and pathogenic tau, and neuroinflammation. While recent research suggests that such theories are plausible, additional longitudinal studies linking microorganisms to Aß and phospho-tau development, neuroinflammation, and clinically defined Alzheimer’s dementia are needed.
AB - Purpose of Review: Herein, we provide a critical review of the clinical and translational research examining the relationship between viral and bacterial pathogens and Alzheimer’s disease. In addition, we provide an overview of the biological pathways through which chronic infection may contribute to Alzheimer’s disease. Recent Findings: Dementia due to Alzheimer’s disease is a leading cause of disability among older adults in developed countries, yet knowledge of the causative factors that promote Alzheimer’s disease pathogenesis remains incomplete. Over the past several decades, numerous studies have demonstrated an association of chronic viral and bacterial infection with Alzheimer’s disease. Implicated infectious agents include numerous herpesviruses (HSV-1, HHV-6, HHV-7) and various gastric, enteric, and oral bacterial species, as well as Chlamydia pneumonia and multiple spirochetes. Summary: Evidence supports the association between multiple pathogens and Alzheimer’s disease risk. Whether these pathogens play a causal role in Alzheimer’s pathophysiology remains an open question. We propose that the host immune response to active or latent infection in the periphery or in the brain triggers or accelerates the Alzheimer’s disease processes, including the accumulation of amyloid-ß and pathogenic tau, and neuroinflammation. While recent research suggests that such theories are plausible, additional longitudinal studies linking microorganisms to Aß and phospho-tau development, neuroinflammation, and clinically defined Alzheimer’s dementia are needed.
KW - Alzheimer’s disease
KW - Bacterial infection
KW - Chronic infection
KW - Dementia
KW - Neuroinflammation
KW - Viral infection
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U2 - 10.1007/s40588-021-00168-6
DO - 10.1007/s40588-021-00168-6
M3 - Review article
C2 - 35186664
AN - SCOPUS:85105333847
SN - 2196-5471
VL - 8
SP - 199
EP - 212
JO - Current Clinical Microbiology Reports
JF - Current Clinical Microbiology Reports
IS - 4
ER -