Oral Administration of All‐Trans Retinoic Acid Suppresses Experimental Periodontitis by Modulating the Th17/Treg Imbalance

Background: A T-helper 17 (Th17)/regulatory T (Treg) imbalance has been suggested recently to play a role in the development of periodontitis. All-trans retinoic acid (ATRA) has been reported to modulate Th17/Treg imbalances in some diseases. However, the effect of ATRA on periodontitis remains unknown. This study observes the effect of ATRA on Th17/Treg imbalance modulation in experimental periodontitis.Methods: Experimental periodontitis was induced in mice by oral infection with Porphyromonas gingivalis (P. gingivalis). ATRA was orally administered every other day. Alveolar bone resorption (ABR) was estimated by measuring the distance from the cemento-enamel junction to the alveolar bone crest. CD4+ T-cell subsets in the cervical lymph nodes (CLNs) and spleen were analyzed by flow cytometry. Th17/Treg cell–related cytokine messenger ribonucleic acid expression was quantified by real-time reverse transcription-polymerase chain reaction.Results: The present data shows that ATRA suppressed ABR and inhibit...