Influences of periodontitis on hippocampal inflammation, oxidative stress, and apoptosis in rats

Abstract

Background and aim:The hippocampus, which has a central role in cognitive and behavioral activities, is one of the most sensitive parts of the brain to systemic inflammatory diseases. This animal study aims to comprehensively investigate the possible inflammatory, oxidative, and apoptotic effects of periodontitis on the hippocampus.Methods: Sixteen male Sprague-Dawley rats were randomly assigned to two groups: control and experimental periodontitis (Ep). In the Ep group, periodontitis was induced by placing 3.0 sutures sub-paramarginally around the necks of right and left mandibular first molars and maintaining the ligatures in place for 5 weeks. Following the euthanasia, mandibula and hippocampus samples were collected bilaterally. Alveolar bone loss was measured histomorphometrically and radiologically on the right and left mandibles. On the right hippocampal sections histological (Caspase-3, TNFα, and 8-OHdG) and the left hippocampal sections, biochemical (IL-1β, Aβ 1-42 , MDA, GSH, and TAS levels) evaluations were performed.Results: Histopathological changes associated with periodontitis were limited (p > .05). A slight increase in caspase-3 positive neuron density in EP rats showed that apoptotic changes were also limited (p > .05). 8-OHdG activity, on the other hand, was significantly higher compared to controls (p < .05). In biochemical analysis, there was a significant increase in IL-1β levels and oxidative membrane damage (MDA) (p < .05) whereas Aβ 1-42 and antioxidant marker (GSH and TAS) levels were slightly increased (p > .05). Conclusion:Periodontitis causes marked increases in IL-1β levels and oxidative stress in the hippocampus, but limited degenerative and apoptotic changes.

Periodontitis‐induced neuroinflammation impacts dendritic spine immaturity and cognitive impairment

“…Therefore, this study chose an 8‐week ligature‐induced CP model. Consistent with previous studies (Kose et al, 2021; Lin et al, 2017), we observed extensive bone destruction in the CP mice.…”

“…Compared with the mousePorphyromonas gingivalis infection model, the ligature-induced periodontitis model may reflect a broader pathogenesis of bone loss and inflammation(de Molon et al, 2014;Lin et al, 2017). In addition, experimental long ligation models are usually preferred in studies that assess the chronic systemic effects of periodontitis on various organ systems(Kose et al, 2021). Therefore, this study chose an 8-week ligature-induced CP model.…”

Melatonin-Derived Carbon Dots with Free Radical Scavenging Property for Effective Periodontitis Treatment via the Nrf2/HO-1 Pathway

“…Our serum detection results using the reagent kits showed that the T-AOC and expressions of antioxidant enzymes, including CAT, SOD, and GSH-Px, in the Perio+MT-CD group were elevated in contrast to the Perio group (Figure I, J, L, and M). Malondialdehyde (MDA), a key indicator of oxidative damage to cell structure membrane phospholipids, exhibited a notable increase in the Perio group, signifying significant oxidative damage in periodontal tissue . The increase in the level of MDA in untreated periodontitis indicates a significant degree of oxidative damage in periodontal tissue (Figure K).…”

“…Malondialdehyde (MDA), a key indicator of oxidative damage to cell structure membrane phospholipids, exhibited a notable increase in the Perio group, signifying significant oxidative damage in periodontal tissue. 73 The increase in the level of MDA in untreated periodontitis indicates a significant degree of oxidative damage in periodontal tissue (Figure 7K). In contrast, MT-CDs demonstrated a significant inhibitory effect on this process.…”