Gingival Crevicular Fluid as Biomarker’s Source for Alzheimer’s Disease

Periodontitis is a low-grade inflammatory disease caused by a subgingival
dysbiotic microbiota. Multiple studies have determined the higher prevalence of tooth
loss and poor oral hygiene in patients with Alzheimer’s disease (AD). However, the
periodontal diagnosis, periodontal bacteria or mediators has not been measured
to date.

Aim: To determine the periodontal status, the pro-inflammatory mediators,
Porphyromonas gingivalis load, and Apoliporpotein E (ApoE) in patients with AD. A
complete dental examination was performed on 30 patients, and cognitive status was
determined by the Montreal Cognitive Assessment (MoCA). Subgingival microbiota and
GCF samples were then taken from all patients from the deepest sites. Total DNA
was isolated from the microbiota samples for the quantification of the 16S ribosomal
subunit. Pro-inflammatory mediators and ApoE were quantified from the gingival
crevicular fluid (GCF). Patients with AD had periodontitis stage III-IV in 80%, a higher
concentration of pro-inflammatory and ApoE mediators, and a higher P. gingivalis load
compared to healthy subjects. The pro-inflammatory mediators, P. gingivalis load had
a negative correlation with the MoCA test scores. Finally, a ROC curve was performed
to assess the specificity and sensitivity of ApoE levels, detecting an area of 84.9%. In
AD patients, we found a more severe periodontitis, a higher levels of pro-inflammatory
mediators, and higher bacterial load. In addition, there is an increase in ApoE that
allows to clearly determine patients with health, periodontitis and periodontitis and AD. CLICK TO REVIEW