The impact of compounds isolated from Ocimum sp. on apoptotic activity of osteoclast

Periodontal disease has multifactorial etiology. The immune response to the microbial challenge leads to osteoclast activation and resorption of the alveolar bone, resulting in tooth loss. Compounds isolated from Ocimum americanum and Ocimum basilicum were analyzed for apoptotic activity towards osteoclast in this study. Steam distillation was used for the extraction of essential oils (EOs) from dry leaves and flowers. The assessment of apoptosis in osteoclasts was carried out through the TUNEL assay and immunocytochemistry for the Fas receptor. The chemical profile of EOs, characterized through gas chromatography-mass spectrometry analysis, revealed methyl cinnamate (O. americanum), linalool, caryophyllene, 1,8-cineole (O. basilicum) as major components. The results showed that essential oils were not able to induce apoptosis in osteoclast; however, linalool (50 to 300 μg.ml-1) induced 75% of apoptotic osteoclasts at non-toxic concentrations and the apoptotic activity was confirmed by the increasing levels of Fas receptor on osteoclasts treated with this compound. This study suggests that linalool could be used to control osteoclast activity. Key words: Essential oil, linalool, Ocimum, osteoclast, periodontal disease.