Salvia sclarea essential oil is used as an aromatic therapy for dysmenorrhea. Sclareol-one of the natural products isolated from S. sclarea-displays anti-inflammatory and antioxidant activities; however, researchers have not yet evaluated the mechanism related to the pain-relieving effect of sclareol. In the present study, we aimed to investigate the potential effect of sclareol in ex vivo and in vivo dysmenorrhea models, as well as its possible mechanism. In the ex vivo study of uterine tissue from Sprague Dawley (SD) rats, the uterine contraction amplitude was observed and recorded. In the in vivo study, we measured the uterine contraction pressure of SD rats and performed writhing tests on mice. The uterine tissues from the writhing test subjects were collected and analyzed by Western blot. The results demonstrated that sclareol inhibited prostaglandin (PG) F2α-, oxytocin-, acetylcholine-, carbachol-, KCl-, and Bay K 8644-induced uterine contraction and possessed an analgesic effect in the writhing test. Sclareol affects the Ca2+ level and regulates oxytocin receptor (OTR), myosin light chain kinase (MLCK), extracellular signal-regulated kinase, p-p38, cyclooxygenase-2 (COX-2), and phospho-myosin light chain 20 (p-MLC20) protein expression. Integrating these results, we suggest that sclareol is a potential alternative supplement for dysmenorrhea.

Sclareol (sclarcol) is an organic compound extracted from sage clary plants. Recent study has showed its anti-tumor effects against breast cancer, gastric carcinoma, osteosarcoma and colorectal cancer. However, its exact mechanisms in inhibiting tumor growth remain unknown. This study thus observed the effect of sclareol on the proliferation of osteosarcoma cells, in an attempt to investigate the role of sclarcol on osteosarcoma growth. MG63 osteosarcoma cell was treated with different concentrations of sclarcol. CCK8 assay was used to test its effect on cell proliferation. LC50 value was then determined to obtain optimal treatment dose. MG63 cells were then divided into control and drug treated group, for measuring apoptosis and mitochondrial membrane potential by flow cytometry, and the expression of cytochrome c, Bax and Bcl-2 by western blot. CCK8 analysis showed that sclareol inhibited MG63 cell proliferation, with an LC50 value at 11.0 μM. Flow cytometry results showed the apoptotic cell ratio was 13.8%, 24.1% and 37.3% after treated with 2.0 μM, 4.0 μM and 8.0 μM sclareol respectively. Compared to control group, sclareol significantly depressed mitochondrial membrane potential of MG63 cells, increased the expression of cytochrome c and Bax, but decreased Bcl-2 expression. In conclusion, Sclareol can inhibit the proliferation of MG63 cells, and induce cell apoptosis and decrease mitochondrial membrane potential suggesting the inhibition of osteosarcoma cells by sclareol might be via both apoptosis induction and decreasing mitochondrial membrane potential.