Citral reduces alveolar bone loss and inflammatory mediators in ligature-induced periodontitis: implications for novel therapeutic strategies

This study investigates the impact of systemic citral administration on healthy and inflamed gingiva, alveolar bone loss, and inflammatory mediators in a rat model of ligature-induced periodontitis since the currently available therapeutics are limited and may have detrimental effects. In this model, a linen thread is placed around adult male rats' first lower right molars for either 7 or 15 days to induce periodontitis. Animals with periodontitis received daily citral [a mixture of monoterpenoids found in lemongrass (Cymbopogon citratus) essential oil] treatment or vehicle via gavage. The distance between the cementoenamel junction (CEJ) and alveolar bone crest (BC) was measured using image analysis software to assess bone loss. Enzyme-linked immunosorbent assay (ELISA) was used to determine levels of TNF-α, IL-6, IL-1β, and IL-10 in the gingiva, as well as TNF-α in plasma. Nitric oxide (NO) levels in gingival tissue were analyzed using the NO-ozone chemiluminescence technique, and MMP-2 levels were assessed through gelatin zymography. The results indicate that systemic citral administration did not affect normal gingiva. However, administering citral for 15 days significantly reduced ligature-induced bone loss, suppressed increased gingival cytokines (TNF-α, IL-1β, IL-6), the elevated local IL-10 levels, decreased TNF-α in plasma and inhibited NO production and MMP-2 expression in animals with periodontitis at both 7 and 15 days. These findings suggest that citral may serve as a novel and potent regulator of gingival inflammation and demonstrate therapeutic effects on bone loss in periodontitis-afflicted animals. São Paulo Research Foundation (FAPESP) grants #23/08395-6 and #22/12290-2. This abstract was presented at the American Physiology Summit 2025 and is only available in HTML format. There is no downloadable file or PDF version. The Physiology editorial board was not involved in the peer review process.