Tau hyperphosphorylation is the important thing attribute pathological hallmarks of Alzheimer’s illness (AD). Recently research confirmed periodontitis and periodontal pathogen are important danger components for AD. Treponema denticola (T. denticola), as the primary periodontal pathogen of periodontitis, has been reported a doable hyperlink with AD, nevertheless, the position of T. denticola in AD pathogenesis continues to be unclear.

In this examine, twenty 8-week-old male C57BL/6 mice had been orally administered T. denticola for twenty-four weeks. T. denticola DNA within the hippocampi of mice was decided by PCR. The ranges and localization of tau phosphorylated at Thr181, Thr231 and Ser396 had been examined by western blotting and immunohistochemistry. The activation of microglia and the degrees of IL-1β and TNF-α had been respectively detected by immunohistochemistry and ELISA. BV2 cells had been co-cultured with T. denticola, then, the activation of BV2 cells was evaluated by immunofluorescence and the expression ranges of IL-1β, TNF-α in BV2 cells had been measured by qRT-PCR and ELISA. The supernatant from BV2 cells simulated by T. denticola was used to stimulated N2a cells, the degrees of hyperphosphorylated tau protein at Thr181, Thr231 and Ser396 in N2a cells had been detected by western blotting.

Orally administered T. denticola colonized the mind tissue, promoted the hyperphosphorylation of tau protein at Ser396, Thr181 and Thr231 within the processes of neurons, activated the microglia and elevated the degrees of IL-1β and TNF-α within the hippocampi of mice. In vitro, T. denticola instantly induced the BV2 cells activation and elevated the expression ranges of IL-1β and TNF-α. Furthermore, the degrees of hyperphosphorylated tau protein at Thr181, Thr231 and Ser396 in N2a cells had been elevated. This examine discovered T. denticola might invade the hippocampi of mice and promote the hyperphosphorylation of tau protein at Ser396, Thr181 and Thr231 by activating the neuroinflammation within the hippocampi of mice.

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International & American Associations for Dental Research