We use cookies to understand how you use our site and to improve your experience. This includes personalizing content and advertising. To learn more, click here. By continuing to use our site, you accept our use of cookies. Cookie Policy.

Features Partner Sites Information LinkXpress hp
Sign In
Advertise with Us
PURITAN MEDICAL

Download Mobile App




Bacterial Pathogen Discovered in Brains of Alzheimer's Patients

By LabMedica International staff writers
Posted on 06 Feb 2019
Alzheimer’s disease (AD) patients exhibit neuroinflammation consistent with infection, including microglial activation, inflammasome activation, complement activation, and altered cytokine profiles.

Infectious agents have been found in the brain and postulated to be involved with AD, but robust evidence of causation has not been established. More...
The recent characterization of amyloid-β (Aβ) as an antimicrobial peptide has renewed interest in identifying a possible infectious cause of AD.

An international team of scientists including those from the University of Louisville School of Dentistry (Louisville, KY, USA) investigated the prevalence of Porphyromonas gingivalis in the AD brain and to elucidate possible P. gingivalis–dependent mechanisms of action for neurodegeneration and AD pathology. P. gingivalis is mainly found during gingival and periodontal infections; however, it can also be found at low levels in 25% of healthy individuals with no oral disease.

The team obtained human postmortem brain tissues and independent pathological analysis confirmed that any amyloid pathology was deemed normal for age in the control cases selected for this study. Human brain tissue microarrays (TMAs) comprised a total of 58 2-mm-diameter core samples, 29 from dementia-free control individuals and 29 from AD cases, each on two arrays. Gingipain antibodies were optimized initially on formalin-fixed paraffin-embedded sections of gingival tissue collected from periodontal disease patients. Histological analysis was performed on an Olympus BX61 motorized microscope. Several molecular techniques were used to identify other factors in the study.

The study team found the organism's toxic enzymes, or gingipains, in the neurons of patients with AD. Gingipains are secreted and transported to outer bacterial membrane surfaces and have been shown to mediate the toxicity of P. gingivalis in a variety of cells. The team correlated the gingipain levels with pathology related to two markers: tau, a protein needed for normal neuronal function, and ubiquitin, a small protein tag that marks damaged proteins. In animal models, oral P. gingivalis infection led to brain colonization and increased production of amyloid beta (Aβ), a component of the amyloid plaques commonly associated with AD.

In preclinical studies the scientists demonstrated that by inhibiting the compound COR388, there was reduced bacterial load of an established P. gingivalis brain infection, blocked Aβ42 production, reduced neuroinflammation and protected neurons in the hippocampus, the part of the brain that mediates memory and frequently atrophies early in the development of AD. The study was published on January 23, 2019, in the journal Science Advances.

Related Links:
University of Louisville School of Dentistry


New
Gold Member
Serological Pipets
INTEGRA Serological Pipets
3-Part Differential Hematology Analyzer
Swelab Alfa Plus Sampler
New
PlGF Test
Quidel Triage PlGF Test
New
Celiac Disease Test
Anti-Gliadin IgG ELISA
Read the full article by registering today, it's FREE! It's Free!
Register now for FREE to LabMedica.com and get access to news and events that shape the world of Clinical Laboratory Medicine.
  • Free digital version edition of LabMedica International sent by email on regular basis
  • Free print version of LabMedica International magazine (available only outside USA and Canada).
  • Free and unlimited access to back issues of LabMedica International in digital format
  • Free LabMedica International Newsletter sent every week containing the latest news
  • Free breaking news sent via email
  • Free access to Events Calendar
  • Free access to LinkXpress new product services
  • REGISTRATION IS FREE AND EASY!
Click here to Register








DIASOURCE (A Biovendor Company)

Channels

Hematology

view channel
Image: CitoCBC is the world first cartridge-based CBC to be granted CLIA Waived status by FDA (Photo courtesy of CytoChip)

Disposable Cartridge-Based Test Delivers Rapid and Accurate CBC Results

Complete Blood Count (CBC) is one of the most commonly ordered lab tests, crucial for diagnosing diseases, monitoring therapies, and conducting routine health screenings. However, more than 90% of physician... Read more

Immunology

view channel
Image: A simple blood test could replace surgical biopsies for early detecion of heart transplant rejection (Photo courtesy of Shutterstock)

Blood Test Detects Organ Rejection in Heart Transplant Patients

Following a heart transplant, patients are required to undergo surgical biopsies so that physicians can assess the possibility of organ rejection. Rejection happens when the recipient’s immune system identifies... Read more
Copyright © 2000-2025 Globetech Media. All rights reserved.