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Medical AI Inquiry: You was designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.  Labels: OBJECTIVE, METHODS, RESULTS. Meshes: Alveolar Bone Loss, Analysis of Variance, Animals, Apoptosis, CD40 Antigens, Carrier Proteins, Disease Models, Animal, Gene Expression, Genetic Predisposition to Disease, Interleukin-1, Interleukin-10, Membrane Glycoproteins, Mice, Mice, Inbred C57BL, Mice, Knockout, Porphyromonas gingivalis, RANK Ligand, Receptor Activator of Nuclear Factor-kappa B, Specific Pathogen-Free Organisms, Up-Regulation.
user
Is the interleukin-10 knockout mouse highly susceptible to Porphyromonas gingivalis-induced alveolar bone loss? Context: Interleukin-10 is an anti-inflammatory cytokine that reduces periapical bone loss, but its role in periodontal bone loss is unclear. In the present study, we tested the hypothesis that endogenous interleukin-10 is a potent suppressor of Porphyromonas gingivalis-induced alveolar bone loss in vivo. Interleukin-10 knockout (-/-) and wild-type mice were inoculated intraorally with P. gingivalis. Non-infected animals served as negative controls. Alveolar bone loss, gingival cytokine levels, and gingival gene expression were assessed using morphometric analysis, enzyme-linked immunosorbent assay (ELISA), and semiquantitative reverse transcription polymerase chain reaction (RT-PCR), respectively. P. gingivalis-infected interleukin-10(-/-) mice exhibited severe alveolar bone loss compared to non-infected interleukin-10(-/-) and wild-type mice by day 42. Surprisingly, bone resorptive cytokines interleukin-1alpha and tumor necrosis factor alpha (TNF-alpha) were not up-regulated in gingival tissues by P. gingivalis-infection. Although interleukin-1beta was marginally increased, blockade of both interleukin-1 isoforms or interleukin-1 receptor type I with neutralizing antisera failed to reduce alveolar bone loss in interleukin-10(-/-) mice, indicating the operation of an interleukin-1-independent mechanism. No strong correlations between bone loss and other cytokines was observed, although interferon gamma (IFNgamma), interleukin-6, interleukin-4, and prostaglandin E2 were modestly up-regulated in infected interleukin-10(-/-) mice. P. gingivalis infection reduced the expression of cell markers in gingival tissue on days 7 and 14 in both interleukin-10(-/-) and wild-type animals, suggestive of bacteria-induced cytotoxicity or apoptosis. This was followed by up-regulated expression of receptor activator of nuclear factor kappa B ligand (RANKL) and CD40 ligand (CD40L on days 28 and 70 in infected interleukin-10(-/-) mice only.
assistant
The interleukin-10(-/-) mouse is highly susceptible to bone loss induced by the periodontal pathogen P. gingivalis, which is mediated via an interleukin-1-independent pathway. Final Decision: yes