Decrease of collagen number density in rat facial skin due to Porphyromonas gingivalis induction in rat model periodontitis

Background: Periodontitis is a chronic inflammatory disease initiated by bacterial dysbiosis in periodontal tissue. Porphyromonas gingivalis (P. gingivalis) is the keystone pathogen of periodontitis with the ability to promote systemic inflammation. They can invade other organs outside oral cavity and enter lymphatic and blood vessels. Its virulence factor can affect tissue integrity by disturbing extracellular matrix regulation, resulting in tissue destruction. One of the extracellular matrix components in facial skin is collagen, which is responsible for facial wrinkles. 

Objectives: To examine collagen number density in rat facial skin due to Porphyromonas gingivalis induction in rat model periodontitis.

Methods: In vivo experimental study conducted with 2 control groups (C1, C2) and 2 treatment groups (T1, T2). The treatment groups received P. gingivalis induction for 3 weeks. The treatment group 1 (T1) euthanized 2 weeks after the bacterial induction, along with control group 1 (C1).  The treatment group 2 (T2) was euthanized 4 weeks after the bacterial induction, along with control group 2 (C2). The facial skin was taken and prepared for Masson Trichrome staining. Statistical analysis was carried out for the collagen number density.

Results: There was significant difference in collagen number density between treatment groups and control groups (p < 0.05). In both treatment groups, the collagen number density is lower than both control groups.

Conclusions: There is a significant difference in collagen number density of rat facial skin between P. gingivalis induced and uninduced, and appears lower in rats induced by P. gingivalis.